text:
San Francisco, CA, May 20, 2014 -- Today, Evoqua Water Technologies Inc. announced an exclusive agreement with water treatment company HydroNovation to supply a newly developed ion-selective membrane pack for HydroNovation's HydroDI™ water treatment system.
The new membranes have ultra-low resistance and are highly selective for divalent ions, desirable for applications requiring reduction of hardness ions, such as calcium and magnesium. HydroNovation will incorporate these new membranes into the HydroDI systems to provide salt-free water treatment for residential and commercial point-of-entry applications.
"We are proud to bring the benefits of the groundbreaking membrane technology pioneered by Evoqua in the industrial and high purity markets to residential and commercial markets in our HydroDI solution." said Anil Jha, CEO of HydroNovation. "Evoqua's highly efficient membrane pack is a crucial element of our eco-friendly water treatment solution and brings us closer to our goal of eliminating the traditional ion exchange softeners which pollute the environment."
Currently, there are more than 11 million traditional salt-based water softeners in the U.S., each dumping an average of 500 pounds of salt into the local groundwater each year. Salt discharge from softeners has become a major concern in Southwest US and several other states, increasing chemical contamination in groundwater.
The HydroDI system utilizes electrical potential combined with membrane filtration technology to remove hardness ions in addition to other harmful contaminants, such as nitrates, lead and arsenic, all without the use of any chemicals. The system includes the capability for the user to dial-in a preferred quality standard, producing ideal water quality for coffee, tea and soda preparation; the result is bottled water quality from every tap.
About Evoqua Water Technologies LLC
Evoqua Water Technologies, formerly Siemens Water Technologies, is a leader in water and wastewater treatment products, systems and services for industrial and municipal customers. Its comprehensive, cost-effective and reliable treatment systems and services reduce fresh water demand, ensure uninterrupted quantity and quality of water, and enable regulatory and environmental compliance. With a wide range of proven product brands and advanced water and wastewater treatment technologies, mobile emergency water supply solutions and service contract options, Evoqua helps cities provide clean water and industrial plants to maintain productivity and profitability. For more information, visit _URL_.
San Francisco-based HydroNovation provides water treatment solutions for residential and commercial applications. Under exclusive license from Evoqua Water Technologies, HydroNovation has developed a unique demineralization technology enabling customers to save water and energy, improve water quality, reduce waste discharge and eliminate chemical handling. Visit _URL_ for more information.


text:
The Office of Academic Quality (OAQ) acts as a centralized point of contact and service related to all curriculum quality assurance processes across the college. OAQ helps to facilitate continuous quality improvement by overseeing academic policy, and ensuring that changes at any credential level are embedded and operationalized in all related processes and procedures.
In supporting student success, OAQ:
- ties curriculum to Ministry guidelines and standards
- provides curriculum support and resources to academic areas
- oversees and facilitates all curriculum processes
- enables evidence-based curriculum decision-making
- acts as a link between the academic areas and relevant stakeholders
The Office of Academic Quality (OAQ) can provide a number of resources with regard to curriculum development and design, work with program teams on curriculum development, and assist with answers to questions about forms, approvals, deadlines and more.
A culture of academic excellence through continuous quality improvement.
To enhance and implement comprehensive academic policies and curriculum processes that inspire best practices and contribute to the quality of the educational experience.

source: openbmb/Ultra-FineWeb


text:
The Castle that Rabbits Built
In 1920, a Central Otago farmer began building a red brick "castle," funded by the meat and skins from the pests on his land. More than a century later, two Aucklanders are trying to finish the job — if they can get permission.
It sounds like it was a wasteland. When Stephen Spain took on the lease for Earnscleugh Station in 1902, the last leaseholder had walked off the property, abandoning it to the Crown after a bitter winter took out half his flock and rabbits had grazed the land bare. But Spain must have thought he could make a go of it. In less than 20 years, the rabbits would make him a fortune.
The 10,000-hectare property is in one of the harshest environments in the country, rising from the dry river flats bordering the Clutha River, to the 1682-metre summit of the Old Man Range, a slumping hulk of schist eroded into enormous wind-scaped tors. According to Māori mythology, these rock towers are the frozen remains of a slain man-eating giant, Kopuwai, and his two-headed hunting hounds.
There's plenty of local yarns swirling around Earnscleugh still. "You get a lot of stories," says Marco Creemers, one of the new owners of Earnscleugh castle, the grand homestead which stands on part of the station. "And a lot of different versions of the same story, and you're never quite sure what's true."
Back in the 1860s, Central Otago's first European settlers brought sheep, then rabbits. Alfred Strode was the first run-holder at Earnscleugh, a veteran of the Wellington Militia fighting in the Hutt Valley and Whanganui in the 1840s who later became police magistrate of Otago. He took on the farm's lease in 1862, just months before the Central Otago gold rush began, which probably proved a bigger boon than sheep's wool or meat.
The station was managed by William Fraser, a 22-year-old Scotsman who later married Strode's daughter, Ellen, became a partner in the farm and went on to become a government minister and knight of the realm.
It was Fraser's idea to bring in the bunnies. He's believed to have been the first to release rabbits in Otago in the 1860s. Initially they were a protected species — Fraser apparently prosecuted a poacher for shooting rabbits on the property. In a little over a decade, he was paying shepherds to shoot them and released ferrets to keep them in check.
Fraser inherited the station from his father-in-law and sold it in 1893 after being elected to parliament, later serving as Minister of Public Works in William Massey's government. The new owner, a WS Laidlaw, didn't last long. The winter of 1895, one of the harshest the country had ever seen, killed off half the station's flock — and almost a million sheep throughout New Zealand. The rabbits left little feed to help the flock recover and Laidlaw surrendered the lease in 1898. He had been reportedly "reduced from a wealthy man to a near-penniless one".
Then came Stephen Spain. According to a Heritage New Zealand report, Spain was "born in a tent on the banks of the Clutha River" near Roxburgh in 1862, the year of the gold rush, grew up in Ophir and went on to become a butcher and a baker in Alexandra.
Papers Past reveals he had been in some strife. He features relatively regularly in the court news. He was charged with not paying his Otago Daily Times subscription in 1893, he defaulted on a cheque in 1894, and was charged with "allowing pigs to wander in a public place" in Alexandra the same year. Then he faced bankruptcy proceedings in 1895.
Somehow, by 1902, he had got enough money together to take on the lease at Earnscleugh. At first it seems the rabbits were more profitable than the sheep. One source claims he employed 32 men for five months, killing a not-inconsiderable 250,000 rabbits.
Spain used the profit from selling rabbit skins to buy stock and was regarded in the district as "a rabbit farmer." But within five years, The Press reported he was shearing a flock of over 12,000 sheep.
Soon the rabbits began showing their worth. During World War I, Spain started a factory in an old brewery in Alexandra canning rabbit meat for the war effort. Local records show the factory employed 90 people at its peak, mostly exporting the meat to Britain and the United States. Under a lucrative contract with the British War Office, the two-pound cans sold for $82.69 each in today's money. The factory could process up to 15,000 rabbits a day, producing 24,000 cans. The skins weren't wasted either: they sold for £1 per pound.
There may have been some subterfuge in this success. Local records claim the cans were mislabelled as "chicken", and a Heritage New Zealand report said "according to rumour" shipments destined for France were labelled "poulet".
By 1919, Spain had amassed a fortune worthy of a castle. He commissioned Edmund Anscombe, one of the top architects of the time, to design a 21-room manor, complete with servants' quarters, stables for his racehorses and a coach house. Anscombe had designed some of Dunedin's most notable and grandiose buildings, including Otago Girls High School (1910 and 1921), and parts of the iconic University of Otago clocktower block and the Haynes' Building (1914) on Princes St, now known as the Savoy. He went on to design the buildings in the grandiose 1939 Centennial Exhibition and later designed the Post and Telegraph building on Wellington's waterfront.
The castle was built in the early 1920s, a red brick "Jacobethan" building — a combination of Jacobean and Elizabethan styles popular in England and the United States at the time. Heritage New Zealand calls it an "eccentric design" and "a tangible manifestation of that tendency of New Zealand runholders to indulge in displays of conspicuous consumption".
But the building was never completed. Anscombe's designs show it with a plastered façade covering much of the brick work and the concrete pillars. Spain ran out of money. Britain's market was flooded with canned meat in the 1920s and the rabbit-canning factory closed in 1924. The subsequent Great Depression also hit Spain's investments, and rabbits abounded at Earnscleugh again.
The castle became known locally as "Spain's Folly" for its eyewatering cost (close to $1 million in today's money) and the fact it was built on Crown-owned leasehold land meaning he was unlikely to be compensated for the manor if he sold the lease or if it wasn't renewed.
Spain died in 1940. The building stayed in the family, but a feud saw it literally divided down the middle. A brick wall was built down the centre and out into the garden to separate the families of the two siblings living there. The saga was alluded to in the 1969 memoir Castle on the Run, written by Spain's granddaughter Gay McInnes, who grew up in the castle in the 1930s.
The Spains sold the castle in 1948. The lease was taken on by a couple of farming and orcharding families. It was freeholded in 1996 and was put on the market last year. Now, new owners have come to Earnscleugh.
If permission is granted, restoration of the castle is expected to take 18 months and finish a project 100 years in the making. Photo: George Driver
Marco Creemers and Ryan Sanders were living in an Auckland apartment, thinking of a life in the country when they learned the castle was for sale. Sanders emailed the listing to his husband, Creemers, saying "stuff it, we'll live here".
They're not exactly this-could-be-us Escape to the Chateau dreamers — they have both property experience and the funds to bring Earnscleugh back to glory. Creemers has been general manager and projects director for 32 years for the Friedlander family's Samson Corporation, one of the largest commercial property owners in Auckland, with a portfolio that includes a fair number of heritage buildings. Starting as a labourer in the company, Creemers is cited as one of the most influential figures in the city's real estate scene.
Sanders grew up in Canterbury and began his career as a professional rugby player, playing for Scottish clubs in the early 2000s. He went on to work in recruitment for a banking firm there, when he realised New Zealand was becoming a bucket-list tourism destination. He put his life savings into starting a tourism business, Haka Tours, in 2007, getting a head start on the tourism boom of the 2010s. In 2019, Deloitte named Haka Tourism Group New Zealand's fastest-growing tourism brand. It now has a portfolio that includes a network of backpacker accommodation under the brand Haka Lodges that employs 190 staff.
Sanders and Creemers flew south for a visit to Earnscleugh on a rainy day in March last year. When they first saw the imposing brick facade, after bumping over rain-filled potholes down the long, unsealed drive, Creemers exclaimed, "Oh my god, we are going to buy this aren't we?"
The couple bought it for what was reportedly "slightly ahead" of its $8.46 million rateable value, along with 12 hectares split off from Earnscleugh Station (which is still a working property of 21,000 ha).
The couple have ambitious plans

source: m-a-p/FineFineWeb


that the minimal value of the transformation of each set, say \(A=\{e,i,o\}\) and \(B=\{a,e\}\), according to a new orderding, \(\pi_X\), is equal to the Jackard Coefficient. In this case we can compute the Jackard Coefficient exactly and it is:
$$\frac{|\{e,i,o\}\cap\{a,e\}|}{|\{e,i,o\}\cup\{a,e\}|} =\frac{|\{e\}|}{|\{a,e,i,o\}|} = \frac{1}{4} $$
This number means that whenever we pick a transformation \(\pi\) from the set of all possible transformations \(\Pi\) the probability that the smaller number is the same in both sets is equal to 0.25. Think that we are talking here about a probability and that it is not a rule. If the permutation choosen at random was the previously defined function \(\pi_X\) then we would have, \(\min\pi_X(A)=\min\{2,3,1\}=1\) that is not the same value as \(\min\pi_X(B)=\min\{5,2\}=2\).
Hashing functions
Defining a random ordering for all the elements of a universe is costly. We have to maintain in memory the tables we saw for the vowels and that can not be practical when the universe of objects is large. So instead of maintaining the explicit random permutation we use the implicit permutation that hashing functions with good properties give us. The good properties we need is that the probability of collision in the universe is low because a random permutation is a 1 to 1 relationship between elements and positions and thus collisions in the hashing function would break this property.
From now on, I'm going to assume that every universe we need to work with is smaller than the range of integers and thus restrict all the derivations to integer since every set and ordering could be mapped to the natural integer ordering (\([0..2^{32}]\)).
Possible hashing functions for integers could be:
 - Use the FNV-1 hashing function of the string representation of your integer. This has the advantage that naturally deals with hashing sets of integers by means of concatenating their string representations.
 - Use a pseudo-random number generator by picking a large prime number, say \(p=_PHONE_\) and a set of coefficients \(\{a_i,b_i\}\) such our hashing functions are defined as \(\pi_i = (a_i x + b_i) \% p \)
In this post we will use the second kind of functions expresed in this Haskell code:
p :: Int
coefs :: [Int]
coefs = unfoldr (Just. randomR (0,p)) $ mkStdGen 0
hashFuncs :: [Int->Int]
hashFuncs = go coefs
 go theCoefs = let (a:b:[],rest) = splitAt 2 theCoefs
 in (\x -> (a*x+b) 'mod' p) : go rest
So, given a hashing function, which is the minimum hash over a given set? This code gives you that result
minHash :: (Int->Int) -> [Int] -> Int
minHash f = foldl' hashAndMin maxBound
 hashAndMin a b = min a (f b)
OK, now you want to compare two sets, A and B to see how similar they are. The similarity measure here will be the number of items they both share, the Jackard coefficient. The time complexity of the set intersection is \(O(n+m)\) if you first build a Hash Map and then query it with the second set for existence. If both sets are already sorted you can compare them in \(O(n)\) \(O(m+n\log n+ m\log m)\).
Can you compare them faster? Yes, but only if you want to trade accuracy. The property in the probability formula at the beginning of the post states that with probability the Jackard coefficient the min hashes of the two sets will be equal. That means that if we take r different hashing functions (permutations) and we name s the Jackard coefficient between the tow sets, the probability that all k hashes of each set are equal is \(s^r\). Since this is a collection of Bernoulli trials, the distribution of having k min hashes equal in both sets follows a Binomial distribution with density probability function equal to:
$$f(k;r,s)= {r \choose k}s^k(1-s)^{r-k}$$
It is known that a random variable distributed according to the binomial distribution, \(X \sim B(r,s)\) has \(E[X]=rs\), so a good estimator of \(s\) would be to divide the number of matches by the number of hashing functions. This would give you the estimated value of the Jackard coefficient. But before comparing two fingerprints we have to compute them:
shingle :: Int -> [Int] -> [Int]
shingle c nums = [minHash f nums | f <- take c hashFuncs]
The shingle function gives us a set of c fingerprints of our original big set of numbers.
So let's see it in action. Imagine that we want to compute the Jackard coefficient between the bag of letters in the phrase Humpty Dumpty sat on a wall and Humpty Dumpty had a great fall. First let's compute the Jackard coefficient according to the definition
import Data.List
import System.Random
import Data.Char
import Data.List
phrase1="Humpty Dumpty sat on a wall"
phrase2="Humpty Dumpty had a great fall"
mkSet = nub. filter isAlpha. map toLower
-- Set 1 is the collection of letters in the first phrase
-- "humptydsaonw"
set1 = map ord $ mkSet phrase1 -- "humptydsaonwl"
-- Set 2 is the collection of letters in the second phrase
-- "humptydagrefl"
set2 = map ord $ mkSet phrase2 -- "humptydagrefl"
jackard = a/b
 a = fromIntegral $ length (set1 'intersect' set2) ::Double
 b = fromIntegral $ length (set1 'union' set2) ::Double
p :: Int
coefs :: [Int]
hashFuncs :: [Int->Int]
hashFuncs = go coefs
minHash f = foldl' hashAndMin maxBound
 hashAndMin a b = min a (f b)
shingles1 = map (\x -> shingle x set1) [1..]
shingles2 = map (\x -> shingle x set2) [1..]
jackard2 = map approxJackard shingles
 shingles = zip shingles1 shingles2
 approxJackard :: ([Int],[Int]) -> Double
 approxJackard (as,bs) = let pairs = zip as bs
 matches = filter (\(a,b) -> a == b) pairs
 num = fromIntegral $length matches :: Double
 den = fromIntegral $ length as :: Double
 in num/den
If we plot jackard2 we have an approximation based on the number of shingles:
Approximating Jackard Coefficient
OK, let me summarize a little bit.
 1. You came here because you have a problem of comparing and object against N different objects and N is very large.
 2. The comparison you want to perform is by computing intersections between the attributes of objects and compute how many are equal.
 3. You want a cheap procedure for computing 2)
So the solution is to transform each object into a set of different values, and then perform the Jackard coefficient on the reduced set of values. For instance, each object could be the set of friends in a social network, and the value c could be for instance just 10. Here we reduce the computation of the intersection from the hundreds to just 10 values. Your friends got summarized in a set of 10 values.
Can we do better? Yes. Here we reduced the number of comparison from the cardinality of the number of features of the object to the small number c. But we still have to perform N comparisons against the N individuals in the population. Wouldn't it be nice to just pick the individuals we think are more likely to have a high Jackard Coefficient? That's possible with the use of bands but since this post is already very long, I'll leave that for another post.
 1. Minwise independent permutations The paper with the math that demonstrates the link between the Jackard Coefficient and the probability.
 2. Chapter 3 of the excellent book "Minning massive datasets"
Categories: Data Mining Tags:,
Training Gradient Boosting Trees with Python
November 5th, 2012 6 comments
I've been doing some data mining lately and specially looking into Gradient Boosting Trees since it is claimed that this is one of the techniques with best performance out of the box. In order to have a better understanding of the technique I've reproduced the example of section 10.14.1 California Housing in the book The Elements of Statistical Learning. Each point of this dataset represents the house value of a property with some attributes of that house. You can get the data and the description of those attributes from here.
I know that the whole exercise here


text:
On Monday, the Surface Transportation Policy Partnership (STPP) released a new report on pedestrian safety in 360 metro areas — and they found that the top four most dangerous walking cities are in Florida. The top ten deadliest cities are all in the South.
The New York and San Francisco Bay areas ranked first and second for the absolute number of pedestrian traffic deaths — but both are also high-population, high-density areas that ranked first and second for the number of people who walk to work. More people are killed by cars because more people are out on the streets.
"Not many people walk to work in Florida," says John Classe, an engineer and vice president of the massive PBSJ corporation, which manages construction projects around the world.
"One big reason is that it is hot for a long period of time," he says. "Weather patterns are also difficult in the summer. Plus, there is not much residential within walking distance of employment." These conditions prevail across the South, which probably explains the rankings in the STPP report.
Perhaps as a result, cities in Florida (where I lived for nine years) are not usually designed for walking or biking — and according to eRedux.com, Florida is the fourth most polluting state in the US. Each Florida resident produces 15 tons of carbon dioxide per year, compared to 11 tons in California and New York (which is nothing to brag about, by the way).
When the STPP divided pedestrian deaths per 100,000 people by the number of people walking to work in the metro area, it turned out that you are most likely to be killed on foot in the Orlando, Tampa-St. Pete, Miami, and Jacksonville areas.
Classe lives in Orlando; I met him last week at the Urban Land Institute meeting in San Francisco, introduced by our mutual friend Daniel Delisi, a planning consultant in South Florida. Classe directed the planning, design, and construction of Baldwin Park, just outside of Orlando, which has won numerous awards for its energy efficiency and walkable design. (See photo at left.) The planned community features 15 parks, more than 200 acres of lakes, and more than 50 miles of walking paths.
Classe started off our conversation by describing how Baldwin Park was built along a major corridor for people commuting to downtown Orlando for work. Most neighborhoods in Florida, he and Delisi explained to me, are designed with two ways in and out (as a teenager in Ormond Beach, Florida, I actually lived in a development designed in exactly that way). As a result, residents must often drive long, roundabout distances in order to reach their strip malls and supermarkets. This is why Floridians often object to dense development — they fear the traffic.
Not so at Baldwin Park. The development is relatively dense and walkable, Classe proudly told me, and residents have 32 points of ingress and egress with their cars. This disperses the traffic and also reduces the amount of driving that residents must do — they can get in and out of the neighborhood more quickly.
But when I asked Classe about light rail (thinking that a neighborhood where everyone commutes downtown would need it), his eyebrows rose as though I had posed an odd question. "There was an effort to establish light rail in the Orlando area several years ago," he said, "but it was killed."
A week later, I described Baldwin Park's design to a transportation engineer for the city of San Francisco–and she also looked at me strangely. "How does that help reduce the carbon footprint?" she asked. "That's crazy. It's better than nothing, but I wouldn't call it 'sustainable.'"
Those two reactions reveal the disparities in perspective between places like San Francisco and cities like Orlando.
"Maybe I have my head in the ground, maybe I spend too much time on the two coasts, but it does feel to me like this country is beginning to reshape or modulate its consumerism, and that is the first step toward sharing," Zipcar founder Robin Chase told me in our Shareable Q&A. I share Chase's hopes, but conversations with folks like Classe and Delisi remind us that word of the sharing revolution hasn't yet reached places like North Central Florida. They judge their efforts toward sustainability by a different standard than does a transportation engineer in San Francisco.
Delisi and I met as students working on environmental issues in Boston. He's taken those values with him as a planner to Florida, hoping to make a difference, but over the years he's had to content himself with small victories. "Success for me in South Florida is building a strip mall that people can walk to," he told me. But why should those people walk, the STPP report suggests, if they are so likely to be hit by cars?
Florida doesn't necessarily lack money for pedestrian and bike safety; it lacks the political and cultural will. It's not alone among the states.
Since 1992, the Transportation Enhancements (TE) program has set aside 10 percent of each state's federal aid for green transport. But the authors of the STPP report (fittingly titled "Dangerous by Design") found that most states have spent only 80 percent of the nearly $9.4 billion made available through the TE program, and only 35 percent of the Safe Routes to Schools program since 2005.
What's the solution?
Developments like Baldwin Park may not be perfect, but they suggest that Florida can take steps in a more sustainable direction. State and federal policy changes would help: The report recommends requiring that federal safety money be spent in an amount proportional to the risk facing pedestrians and that we adopt a national "complete streets" policy that would require cities and counties to accommodate all road users. But in the end, that's not enough.
"There still is a long way to go to repair the damage done to communities in the past, even as we begin to shift policies and design philosophy to build streets that are safer for pedestrians and motorists alike," says the STPP.
However, there are a growing number of excellent models to build on and thousands of communities eager to move forward. The forthcoming rewrite of the nation's transportation policy presents a once-in-a-generation opportunity to create safer streets that will be critical to keeping our neighborhoods livable, our population more fit and our nation less dependent on foreign oil.


When creating or editing a form, how can you copy multiple items/sections?
I am a developer for Cognito Forms.
First, if you are trying to capture the same information multiple times, you can use a Repeating Section, which is a section that the user filling out the form can repeat as necessary to enter the same information for a list of items, like players on a baseball team, employment history, medical conditions, etc.
Example of Repeating Sections
Second, while you can only copy one thing at a time, you can place a number of items (including both fields and other sections) into a section, and then copy and paste the entire section and all of the items contained in the section will be copied as well.
Your Answer


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Month: December 2013
Silence as a Service
Silence as a Service
Bear with me for a moment here. This is mostly a thought experiment.
As I travel around looking at different kinds of spaces, I've started to question our relentless quest for total silence in libraries. Libraries have come to mean silence in our culture; why is that? Because silence is associated with reading? (Of course, only with modern reading: we know that medieval European readers considered reading a verbal activity, always done aloud, and if you've ever found yourself mouthing the words you're reading on a page, you know we're fighting our bodies to make reading silent. No need to be elitist about it: text is only a series of symbols representing speech. There's no shame in it triggering our verbal centres. That's perfectly natural.) When libraries are closed-stack, and the spaces inside it exist only as a reading room for material you can't copy and can't take out with you, I can understand the focus on silence. To a degree, anyway. Silence is meant to go along with concentration. And libraries are meant to be places where you go to concentrate, right?
Everywhere I go, I find students and the self-employed deliberately seeking out spaces that are not silent. Some of them are downright raucous. A lot of them have jazz playing in the background, coffee grinders, conversations, laughter. Some of them are quieter than others, but none of them are silent. I've seen several co-working spaces, and a few high-tech businesses here and there. No private offices, only shared tables, conference rooms, kitchens and "libraries". Nooks for groups, couches, lots of earphones in the ears of those trying to buckle down and work alone. No spaces with a fixation on providing absolute silence, though.
I've been considering whether my comparisons with cafés and co-working spaces are entirely fair. I realize I'm looking at a particular sample of the population, the people who want to work this way. These are people who have a quiet space at home and find it difficult to work like that. These are people who want to be tangentially connected to other people while doing independent work, even if they're strangers. I think there's probably even a little bit of self-motivation going on; when I finish this paper, I can go home and relaxBeing somewhere other than at home helps you stick to a deadline and helps manage your time. That's really healthy, I think. Co-workers in particular often need that separation between home and work to help give the work day a sense of closure, something students and academics both frequently fail to do well. The people I see working this way have quiet space elsewhere if they really need it.
But then I thought: don't our student populations have this as well? Not all of them, maybe. But what percentage of the student populations don't have a room of their own with a door that closes? I imagine it's pretty small. So far my experience of residences on campus always includes some form of study room (and often study groups, as well.) For campuses where students can easily go back and forth from home where they can have silence and solitude, it seems to me that there's more in common between libraries and other public and commercial spaces like cafés than we may have thought.
My own campus has it's own rhythms and issues. Students can't easily come and go from home, and many of them commute in quite a distance. They are effectively stuck on campus, and they may need that silence because they legitimately can't get it anywhere else between the hours of 8am and 9pm. Again, I'm not entirely sure why the library is the place required to provide perfect silence, but I suppose that's the tradition as we have it. We're kind of stuck with it.
A lot of the students on my campus commute from their parents' homes, so they share space with other family members. This is generally presented as a reason why no work can get done at home, but I'm not entirely convinced that that's entirely true. Most homes with adult children in them are pretty quiet. Parents are usually supportive of students working hard on their school work. (Not always, I know. There are always stories and circumstances.) I would suspect that, most of the time, residence is far louder than anyone's household, and even residences have silent spaces in them.
Why are we promising to provide absolute silence, something so difficult to maintain it is practically impossible, if the vast majority of our patrons already have access to it when they need it?
Too harsh? Bear with me a moment longer.
Here's a statistic I don't know: what percentage of our student populations would sit in a comfy chair in a Starbucks and write an essay if they knew no one was going to harass them to buy anything or glare at them to give up their table. As far as I can see, we expect that about 70-80% of our students want to work in complete silence. If that's true, 70-80% of students should abhor working in a public place like a Starbucks. I find that exceedingly unlikely, but I don't know what those stats actually look like.
Maybe the music is too loud: okay. how about a little indie café in the distillery district, or buried in the annex behind a bookstore? Somewhere with ambient music, soft conversations, coffee. Not too busy, not too quiet. Alive. I don't know the statistic; I don't know how many students would be happy to work there. Walking around London, seeing the 3/4ths empty and quiet Senate House library, and the jammed and happily buzzing public libraries, the full cafés of Islington, Hampstead and Shoreditch, the students lining the tables at the Barbican and Southbank Centre, I struggle to imagine that it's a small percentage. But I don't know. This is critical information to me at this point. I'm going to have to find a way to get it.
I haven't said it yet, but I'm sure you can feel it coming. What if most students don't actually require absolute silence to do really good work?
I can already hear the objections. I've seen them; students in my library complain about the noise all the time. I can't keep saying "bear with me" whenever I say something outrageous, can I? But what if this is in part based on expectations that we've set, both through our policies, our space design, and through our powerful public image? What if they demand silence between they just imagine they can expect it, and should expect it, because we've promised it, not because they actually require it? We are allowing students to have unrealistic expectations of our entire buildings, top to bottom. Libraries are meant to be silent, so every sound they hear is annoying.
What if we designed spaces based on the presumption that most students don't need absolute silence, but want a comfortable level of ambient sound that isn't too annoying, much like a half-empty café? What if we designed lots of different kinds of spaces, the kinds of spaces cafés and other public spaces increasingly have, with coffee/tea available, but no pressure to get out of your seat and give your table to someone else? What if we created that for 70-80% of our spaces?
There's still the question of silence.
I seem anti-silence at the moment, but I'm not, really. I'm only asking questions. I'm only suggesting that the desire for absolute silence might not be felt by the majority, as long as if there is other, really functional, comfortable, not overwhelmingly-noisy spaces on offer that clearly doesn't promise something it can't deliver. There will certainly be people who want absolute silence.
What if silence becomes a specialized service? Perhaps the way to break the association of a library with perfect silence in all places is to create a space that is specifically designed and pitched as entirely silent? Enclosed, with a clear demarcation between the normal zone and the dead quiet zone. If you're in here, you're here to be totally, completely, utterly quiet. No phones. Maybe no wifi. Maybe no 3G at all (if that's even legal.) No ipods, no music, because sometimes you can hear them and that's annoying. Nothing: just silence. Quiet keyboards only? How extreme can you reasonably get?
I don't know the statistics, so I don't know for a fact what size a space like that would need to be to accommodate the people who would want it, but from what I see so far, I imagine it probably doesn't need to be monstrous. Maybe it's nestled in among the stacks, using the books to muffle even the sounds of keyboards and pencils scratching. But it's strict, exclusive, and maybe you even need to apply to be allowed in. It would have a zero tolerance policy. It would, I imagine, build it's own culture and empower students to tell each other to shut up should they need to. The eye conversations would be epic.
We are currently encumbered by the idea that the silence rule currently applies to anything called a library. Most libraries tell you to shhh with their staff and their signage. We tell you what your behaviour has to be from one area to the next. But what if, instead of telling people how to behave, we offer the spaces where the behaviour restrictions are a service?
In some ways it's just a matter of rebranding, isn't it. but I know for a fact that just rebranding the quiet areas


Generate Identifiers Using JPA and Hibernate
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How do you get the primary key values in your application? Do you use natural keys or do you generate technical IDs?
I prefer to generate simple, numerical, technical IDs like you can see in the following code snippet instead of using natural keys which often require the combination of multiple attributes.
@Id
private Long id;
Technical IDs are easier to manage and all involved systems, mainly the database and Hibernate, can index them very efficiently. This allows you to focus on the business logic of your application and avoids performance issues.
4 options to generate primary keys
The JPA specification supports 4 different primary key generation strategies which generate the primary key values programmatically or use database features, like auto-incremented columns or sequences. The only thing you have to do is to add the @GeneratedValue annotation to your primary key attribute and choose a generation strategy.
@Id
@GeneratedValue
private Long id;
GenerationType.AUTO
The GenerationType.AUTO is the default generation type and lets the persistence provider choose the generation strategy.
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
If you use Hibernate as your persistence provider, it selects a generation strategy based on the database specific dialect. For most popular databases, it selects GenerationType.SEQUENCE which I will explain later.
GenerationType.IDENTITY
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The GenerationType.IDENTITY is the easiest to use but not the best one from a performance point of view. It relies on an auto-incremented database column and lets the database generate a new value with each insert operation. From a database point of view, this is very efficient because the auto-increment columns are highly optimized, and it doesn't require any additional statements.
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
This approach has a significant drawback if you use Hibernate. Hibernate requires a primary key value for each managed entity and therefore has to perform the insert statement immediately. This prevents it from using different optimization techniques like JDBC batching.
GenerationType.SEQUENCE
The GenerationType.SEQUENCE is my preferred way to generate primary key values and uses a database sequence to generate unique values.
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It requires additional select statements to get the next value from a database sequence. But this has no performance impact for most applications. And if your application has to persist a huge number of new entities, you can use some Hibernate specific optimizations to reduce the number of statements.
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE)
private Long id;
If you don't provide any additional information, Hibernate will request the next value from its default sequence. You can change that by referencing the name of a @SequenceGenerator in the generator attribute of the @GeneratedValue annotation. The @SequenceGenerator annotation lets you define the name of the generator, the name, and schema of the database sequence and the allocation size of the sequence.
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "book_generator")
@SequenceGenerator(name="book_generator", sequenceName = "book_seq", allocationSize=50)
private Long id;
GenerationType.TABLE
The GenerationType.TABLE gets only rarely used nowadays. It simulates a sequence by storing and updating its current value in a database table which requires the use of pessimistic locks which put all transactions into a sequential order. This slows down your application, and you should, therefore, prefer the GenerationType.SEQUENCE, if your database supports sequences, which most popular databases do.
@Id
@GeneratedValue(strategy = GenerationType.TABLE)
private Long id;
You can use the @TableGenerator annotation in a similar way as the already explained @SequenceGenerator annotation to specify the database table which Hibernate shall use to simulate the sequence.
@Id
@GeneratedValue(strategy = GenerationType.TABLE, generator = "book_generator")
@TableGenerator(name="book_generator", table="id_generator", schema="bookstore")
private Long id;
Summary
As you've seen, JPA offers 4 different ways to generate primary key values:
 1. AUTO: Hibernate selects the generation strategy based on the used dialect,
 2. IDENTITY: Hibernate relies on an auto-incremented database column to generate the primary key,
 3. SEQUENCE: Hibernate requests the primary key value from a database sequence,
 4. TABLE: Hibernate uses a database table to simulate a sequence.
I prefer to use the GenerationType.SEQUENCE because it is very efficient and allows Hibernate to decide when to perform the insert statement. This provides the required flexibility to use other performance optimization techniques like JDBC batching.
When you like to learn more about performance tuning and how Hibernate can optimize the GenerationType.SEQUENCE, have a look at my Hibernate Performance Tuning Online Training.
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 1. very interesting article,
 I'm struggling to use @GeneratedValue on none Id column with custom sequence generator how is that possible?
 2. Hi, nice article!
 Reviewing our legacy application, with about 100 entity classes, there is a mixture of @GeneratedValue strategies, including lots of Table strategies. I'd like to make them all use Sequence now on the basis of this article. Can I just replace the annotations, or will this risk duplicate primary key errors in production, in tables where id generation strategy has changed ? The database is MySQL 5.7
 Thanks Richard
 1. Hi Richard,
 you can replace the annotations if you make sure that your database sequence only returns values that are higher than the previously used ones.
 Regards,
 Thorben
 3. I am upgrading hibernate from 3.5 to 5.1.15.
 Earlier i was using custom table generator to generate primary key.
 I am using mysql database, i suppose it does not support sequence.
 Due to hibernate 5 chnages, my code for custom table generation is failing.
 More detail is in this hibernate forum.
 _URL_
 I need to know 2 things
 1. Should i replace table generation, if so how can i do it ?
 2. If i need to retain, custom table generation what should i do in getNextValue() as doWorkInNewTransaction is deprecated.
 1. Hi Sandeep,
 You should the GenerationType.IDENTITY with an autoincremented database column instead of the table generator.
 Regards,
 Thorben
 4. How can i get the next auto increament number?
 1. You don't need to worry about that. Your database returns it in the response the SQL INSERT statement and Hibernate automatically sets it on your entity.
 5. With Hibernate 5.x, GenerationType.AUTO leads to the TABLE generator being used on MySQL DBs. This has performance impacts and it is not working with Galera cluster, as Galera needs a PK on every table, but the hibernate_sequence table does not define a PK.
 Setting
 @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="native")
 @GenericGenerator(name = "native", strategy = "native")
 would use the IDENTITY generator on MySQL, but that leads to other problems when using TABLE_PER_CLASS, as MySQL does not support GenerationType.SEQUENCE.
 See _URL_
 6. Hello
 What if I have a table with a unique ID field (PK Key) that is entered manually (or via a code), and for entering a new record, next record pk is set MAX(ID) + 1.
 How do I annotate the entity so that jpa will let me insert (save) a record while allowing the id value to be provided as part of the post?
 Thank you
 1. Hi Mark,
 just skip the @GeneratedValue annotation, if you want to set the primary key value programmatically.
 Regards,
 Thorben


everything has gone well, we should be able to read the results in the Hash data structure as:
redis-cli> hgetall click:test
1) "asset"
2) "test"
3) "count"
4) "1"
3. Query the data: Reading Redis data as DataFrames
This last component of our solution essentially provides an SQL interface to our Redis data. Reading the data via SQL commands is once again a two-step process: a. we define the SQL schema for Redis data, b. we run the SQL command.
[Click on the image to enlarge it]
Figure 5. Data Querying
But before all this, we need to run spark-sql on our console from our home directory as shown below:
$ spark-sql --jars
./lib/spark-redis-2.3.1-SNAPSHOT-jar-with-dependencies.jar
This will take us to a spark-sql prompt as below:
spark-sql>
Now, we define the SQL schema for the data stored in the Redis Hash data structure. If you remember, we're storing data for each asset in a Hash data structure denoted by the key, click:<asset id>. The Hash has our other key, count. The command to create the schema and map it to the Redis Hash data structure is:
spark-sql> CREATE TABLE IF NOT EXISTS clicks(asset STRING, count
INT) USING org.apache.spark.sql.redis OPTIONS (table 'click')
This command creates a new table view called "clicks". It uses the directives specified in the Spark-Redis library to map columns "asset" and "count" to the respective fields in Hash. Now we can run the query as:
spark-sql> select * from clicks;
test 1
Time taken: 0.088 seconds, Fetched 1 row(s)
If you want to run our SQL queries programmatically, refer to the documentation provided by Apache Spark on how to connect to the Spark engine using ODBC/JDBC drivers.
What did we accomplish?
In this article, I demonstrated how to use Redis Streams as a data source for the Apache Spark engine, as well as how Redis Streams can power a Structured Streaming use case. I also showed how to read Redis data using the DataFrames API in Apache Spark, and put the independent, stand-alone Structured Streaming and DataFrames concepts together to show what you can achieve using the Spark-Redis library.
Redis Streams simplifies the task of collecting and distributing data at a high speed. By combining it with Structured Streaming in Apache Spark, you can power all kinds of solutions that require real-time computations for scenarios ranging from IoT, fraud detection, AI and machine learning, real-time analytics, and so on.
About the Author
Roshan Kumar is a senior product manager at Redis Labs, Inc. He has extensive experience in software development and product management in the technology sector. In the past, Kumar has worked at Hewlett-Packard, and a few successful Silicon Valley startups. He holds a bachelor's degree in Computer Science, and an MBA from Santa Clara University, California, USA.

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Community comments
 - Great tutorial !
 by Mariano Ruiz,
 Your message is awaiting moderation. Thank you for participating in the discussion.
 Great tutorial , very practical
 - Scaling streams
 by Shivakumar Ramagopal,
 Your message is awaiting moderation. Thank you for participating in the discussion.
 Roshan,
 Great write-up on using Redis and Spark for streaming and stream processing! I'm a heavy user of Redis and look forward to using the stream functionality in the near future.
 Question: How is scaling of readers/writers handled in Redis, especially in cluster mode?
 Thanks,
 Shiva
 - Re: Scaling streams
 by Roshan Kumar,
 Your message is awaiting moderation. Thank you for participating in the discussion.
 Shiva,
 Thanks for your kind words. Feel elated :-).
 To answer your question, Stream in Redis is just another data structure (just like List, Set, Sorted Set, Hash, etc.). Therefore, scaling with Stream is same as scaling with the other data structures in Redis. With that said, you have a few options if you are running Redis in a cluster mode:
 1. You can control how to distribute your keys across multiple shards. Read more about that here: redis.io/topics/cluster-spec. You may be interested in reading "Keys hash tags" section of the article.
 2. If you are using Redis Enterprise, then it automates some of the steps that you would otherwise do manually. Read more about it here: _URL_-enterprise/technology/linea...
 Let me know if that answered your question.
 Regards,
 Roshan
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The mission of the Internal Audit Department is to provide independent and objective reviews and assessments of the business activities, operations, financial systems and internal accounting controls of Montclair State University.
The Internal Audit Department accomplishes its mission by carrying out a plan of operational, financial and performance audits, selected as a result of an ongoing review of the key processes and risk levels. This audit plan is reviewed and approved by the President of Montclair State University and the Audit, Finance and Investment Committee of the Board of Trustees.
The Internal Audit Department conducts independent reviews and appraisals of the University procedures and operations. These reviews provide management with an independent appraisal of the effectiveness of various operations and systems of control by seeking to:
- Evaluate the adequacy of the internal control structure
- Assess compliance with written policies, procedures, laws and regulations
- Evaluate the reliability of information reporting systems for financial and other operating data
- Verify the existence of assets and ensure proper safeguards for their protection
- Review the application of information technology for governance, control and assurance
- Maximize the operational effectiveness and use of the university resources.
The Internal Audit Department seeks to assist management by:
- Conducting continuous quality improvement programs
- Promoting operational effectiveness and efficiency
- Reviewing and evaluating financial and operational controls
- Providing pro-active consultation and advice on operational and control related matters
- Liaison with management on dealings with external auditors
- Conduct investigations as necessary
- Recommending best practices.


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Fix a positive real number d>0. Szemeredi's theorem implies that for every integer k, there exists an integer N(k,d) such that if A is a subset of the interval [1,N] with density greater than d >0, then A contains a k-term arithmetic progression.
Let us now define a half AP of length 2N, to be a AP of 2N integers, say S, such that S intersect A is exactly either the first half or the second half of S. Note that we do not require S to be completely contained in [1,N]. That is if A=[1,10] then S=[-9,10] is a half AP of length 20.
Edit: On the other hand, however, the elements of S that do not intersect A can lie in [1,N]. For example, if A=[4/10N, 5/10N] it is valid to take S = [3/10N,5/10N] to produce a half AP of length 2/10N.
Does there exists an integer N(k,d) such that if A is a subset of [1,N] of density d>0 then we can find a half AP of length k?
share|improve this question
I assume we want S to be an AP in addition, here? Otherwise it's trivial... – Harrison Brown Oct 29 '09 at 20:47
Fair point. I've adjusted the question. – Mark Lewko Oct 29 '09 at 22:18
2 Answers 2
Here is the proof for k=6 (i.e. we look for 6-half-AP with 3-elements in the set, and 3 outside). First, by Roth's theorem there is a 3-AP. Let {a,b,c} be the 3-AP with the maximum value of c. If there is more than one 3-AP with this value of c, choose one with the minimum value of a. Now consider only those elements of A that lie in the same arithmetic progression as {a,b,c}. After affine transformation we can assume that {a,b,c}={0,1,2} (I no longer assume that my set is a subset of [1,N]). Now, 3 is not in A because if it was, then {1,2,3} would be a longer 3-AP. Similarly, 4 is not in A for the fear of {0,2,4} being a 3-AP. Then 5 is in A because otherwise 0,1,..,5 is a 6-half-AP. Since 5 is not part of any 3-AP, it follows that -5,-3 and -1 are not in A. Since -3,-2,-1,0,1,2 is not 6-half-AP, we conclude that -2 is in A. However, -2,0,2 is a 3-AP in A with the same value of c, but smaller value of a, contradicting our choice of {a,b,c}.
My guess on this problem is that the answer is 'yes' in general, but I do not have great confidence. The general framework in which this problem falls is the following. Given an induced structure one wants to find, and large ambient structure in which to look, the large structure usually contains the small unless the large structure is of very special form. The induced structure here is k-half-AP, large structure here is a subset A of Z/pZ, and'special form' is that the subset should be either nearly empty or nearly equal to Z/pZ. Given the current techniques for proving Szemerédi's theorem are 'local' (they find a density increment on some local piece), it might be a tough problem. If we knew the inverse conjecture for Gowers norms, it might be more attackable, but that conjecture is still in the works. Of course, it might happen that some simple trick, like one above can be used to deduce this problem from Szemerédi's theorem.
share|improve this answer
Boris, thanks for your comments! I like your proof of the k=6 case. It seems, however, that the k=6 argument can't (at least naively) be extended to the case of k=8. To see this, find the 4-AP with a maximal largest element and (of these) a minimal smallest element. Now pass to the sub-progression containing this 4-AP (and relabel the progression as {0,1,2,3}). The intersection of our set with this progression could look like {-3,0,1,2,3,7}, which doesn't contain a 8-half-AP. Establishing the k=8 case would be very interesting. – Mark Lewko Nov 6 '09 at 22:52
I don't think we can do this for all k and d. Look at the subset of [1,N] consisting of all points greater then (4/10)N and less then (5/10)N this will have density 1/10 and any half arithmetic progression of length 4 will have to hit the set twice so the the difference of the arithemetic progression must be 1/10 of N or less but the arithmetic progression must jump from below zero or above N and hence must have difference greater than 4/10 N which gives a contradiction.
share|improve this answer
Crystal, thanks for your comments. My question wasn't very clear (I've attempted to update it). I intended for it to be permissible for the half of S that does not intersect A to lie in [1,N]. For example, if A=[4/10N, 5/10N] it is valid to take S = [3/10N,5/10N] to produce a half AP of length 2/10N. – Mark Lewko Oct 29 '09 at 22:28
Your Answer


text:
The computations in the analysis of any equireplicate design can be carried out very easily if the number of treatments common to any two blocks is constant. A design with this property is called a Linked Block (LB) design and was introduced by Youden. It is well known that for a Balanced Incomplete Block (BIB) design to have a constant number of treatments in common between any two blocks, it is necessary and sufficient that it is symmetric, that is, the number of blocks is equal to the number of treatments. In this paper, necessary and sufficient conditions are derived for any design with a given treatment-structure matrix to be of the LB type and the results applied to Partially Balanced Incomplete Block (PBIB) designs. Finally a list is prepared of all LB designs in the class of two-associate PBIB designs enumerated by Bose, Shrikhande and Clatworthy.
"On Partially Balanced Linked Block Designs." Ann. Math. Statist. 28 (2) 488 - 493, June, 1957. _URL_


text:
Milk pasteurization: efficiency of the HTST process according to its bacterial concentration
The efficiency of milk pasteurization (HTST) related to its standard plate count (SPC) values were assessed in 41 milk samples using a laboratory designed pasteurizing equipment. Based on results, it is demonstrated that efficiency of the process is affected by its bacterial concentration, where lower SPC values mean decrease in efficiency and that the performance of the process is not affected in presence of high SPC values in raw product.
All journal content is authorized under a Creative Commons (attribution BY-NC type) license. This license lets others remix, adapt, and create works derived of your study, but its commercial use is prohibited. The new works should mention your name in the credits and also cannot be used commercially. However, the derivative works need not be licensed under the same terms of this license.


text:
The length of this lunation is 29 days, 15 hours and 31 minutes and it is 13 minutes longer than the upcoming lunation's length. This is the year's longest synodic month of 2093. The lengths of the following synodic months are going to decrease with the lunar orbit true anomaly getting closer to the value it has at the point of New Moon at perigee (∠0° or ∠360°).
Lunation length longer than mean
The length of the current synodic month is 2 hours and 47 minutes longer than the mean synodic month length. It is 4 hours and 16 minutes shorter compared to 21st century's longest synodic month length.
Lunar orbit details for
True anomaly ∠167.5°
The true anomaly of the Moon orbit at the beginning of this lunation cycle is ∠167.5° and at the beginning of the next lunar synodic month the true anomaly is going to be ∠190.3°.
Moon at apogee
Moon is at apogee at 06:06 about 14 days since last perigee on 10 June 2093 at 08:55 in ♑ Capricorn the lunar orbit is going to narrow while the Moon is moving towards the Earth over the upcoming 13 days until point of next perigee on 8 July 2093 at 18:17 in ♑ Capricorn.
This apogee Moon is 406 382 km(252 514 mi) away from Earth. It is 974 km further than the mean apogee distance, but it is still 327 km closer than the farthest apogee of 21st century.
Moon in ascending node
Moon is in ascending node in ♋ Cancer at 19:10 crossing the ecliptic from South to North. Lunar position remains north of if for the upcoming 13 days until Moon's next descending node later on 9 July 2093 at 06:40 in ♑ Capricorn.
1 day since the last northern standstill on 24 June 2093 at 15:06 in ♋ Cancer when the Moon has reached North declination of ∠21.648° the lunar orbit is extending southward over the next 12 days to face maximum declination of ∠-21.641° at the point of next southern standstill on 8 July 2093 at 09:04 in ♑ Capricorn.


»Visit _URL_ »Contact MetroCount
Axle Position Histogram
The Axle Position Histogram is a histogram of inter-axle spacings within vehicles. This report will usually have a characteristic shape corresponding to common axle spacings, making it an extremely useful tool for verifying data quality.
The Axle Position Histogram can be characterised by:
 1. A group of spikes representing the most common passenger vehicles, and light trucks.
 2. Spikes corresponding to the double and triple axle groups of heavy vehicles (for datasets containing a noticeable percentage of these vehicles).
 3. Smaller spikes corresponding to the longer inter-axle spans in heavy vehicles, such as buses.
 Axle Position Histogram Sample
 Axle Position Histogram Sample
The Axle Position Histogram can be used to check for:
 - matching sensor length, and
 - correct sensor spacing.
Characteristic spikes in the histogram can be checked against known good data from the same area. If these spikes deviate in position by a significant amount, one of these problems may exist, and speed and classification should be considered suspect for this dataset.
For example, it is possible to target the double axle group on the back of an articulated truck, which is usually one of a few standard distances apart. Selecting Properties from the report's right-click menu will display the axle spacings filter.
Inter-axle spacings
Inter-axle spacings
Selecting SP4 in this case will display only the spacings between axles four and five. Note also the X-axis scale can be modified to increase resolution.
Filtering should create a few clearly defined spikes that can be verified using the cross-hairs. Again, deviation from known values may indicate a sensor installation problem.
Filtered Axle Position Histogram
Filtered Axle Position Histogram
For bidirectional data with a suspected problem, it is possible to distinguish between different sensor length and incorrect spacing. Different sensor length will result in spacings that are too short in one direction, and too long in the other. If filtering for one direction using the report Profile's direction filter moves the Axle Position Histogram left or right, this indicates different sensor length. If the report is unmoved, then incorrect spacing is the likely cause.


directed, and an open cover of XX since 𝒰\mathcal{U} is. By hypothesis, XX belongs to 𝒰\mathcal{U}', so XX is a union of finitely many elements of 𝒰\mathcal{U}. This shows XX is compact according to Definition .
As the union is a colimit in the category of open subsets Op(X)Op(X), we can also say
Proposition
XX is compact iff it is a compact object in Op(X)Op(X).
Proof
To say XX is a compact object means that hom(X,):Op(X)Set\hom(X, -): Op(X) \to Set preserves filtered colimits, or colimits of filtered diagrams. Here we may as well replace SetSet by the full subcategory consisting of 0,10, 1 (a 00-element set or a 11-element set) since the hom-sets for posets are of size 00 or 11. Further, in a poset like Op(X)Op(X), a filtered diagram is the same as a nonempty directed diagram DD, and hom(X, dDd)\hom(X, \bigcup_{d \in D} d) has size 11 iff X= dDdX = \bigcup_{d \in D} d. On the other hand, dDhom(X,d)\bigcup_{d \in D} \hom(X, d) has size 11 iff X=dX = d for some dd in DD. Thus that hom(X,)\hom(X, -) preserves filtered colimits amounts to the same thing as saying XX belongs to any directed open cover DD, which is the same as compactness by Proposition .
Compactness via convergence
If the ultrafilter theorem (a weak form of the axiom of choice) is assumed, compactness may be characterized in terms of ultrafilter (or ultranet) convergence:
Proposition
XX is compact iff every ultrafilter 𝒰\mathcal{U} (or ultranet ν\nu) on XX converges to some point xXx \in X, meaning that 𝒰\mathcal{U} contains the filter of neighborhoods of xx (or that ν\nu is eventually in any neighbourhood of xx).
In any case, compactness can be characterized in terms of proper filter or equivalently (see at eventuality filter) of net convergence .
Proposition
XX is compact iff every proper filter/net on XX has a convergent proper refinement/subnet.
This is equivalent to the characterization given in the Idea-section above:
Proposition
XX is compact iff every proper filter 𝒰\mathcal{U} (or net ν\nu) on XX has a cluster point xx, meaning that every element of 𝒰\mathcal{U} meets (has inhabited intersection with) every neighbourhood of xx (or ν\nu is frequently in every neighbourhood of xx).
While the usual definitions (&) are for topological spaces, the convergence definitions () make sense in any convergence space.
Compactness via completeness
A uniform space XX is compact if and only if it is complete and totally bounded. Moreover, a compact Hausdorff topological space has a unique compatible uniformity, which is complete and totally bounded.
In constructive mathematics, "complete and totally bounded" is sometimes taken as a substitute for open-cover compactness (to which it is no longer equivalent); see Bishop-compact space.
Compactness via stability properties
Frequently in category theory, for example when we discuss internal logic in toposes, we are interested in properties of maps that are stable under pullback, and it turns out that compactness can be reformulated in terms of stability properties.
A first example concerns the property of a topological space XX that the unique map !:X1!: X \to 1 to the point space (the terminal object in Top) is a closed map. As a statement in ordinary point-set topology, this is plainly a tautology, trivially true for any space XX. (Side remark: it is not at all a tautology in the more general setting of internal locales in toposes; the word "closed" is reserved for locales XX having that property. See also closed morphism.) However, even in ordinary point-set topology, !:X1!: X \to 1 is usually not stably closed. In more detail: the pullback of !:X1!: X \to 1 along a (or the) map Y1Y \to 1 is the projection map
X×YYX \times Y \to Y
out of the product topological space and the issue is whether this map is closed. This leads us to the following proposition.
Proposition
(closed-projection characterization of compactness)
A topological space XX is compact (def. ) precisely if for any topological space YY, the projection map X×YYX \times Y \to Y out of their product topological space is closed.
Thus, compactness of XX is equivalent to !:X1!: X \to 1 being stably closed. For a proof, see closed-projection characterization of compactness.
Remark
Contrary to possible appearance, the equivalence in prop. does not require the axiom of choice; see this MO question and answers, as well as this page. See also the page compactness and stable closure (under construction). This equivalence is also true for locales, by way of proper maps; see below.
Moreover, the characterization of compact spaces via prop. may be used to give an attractive proof of the Tychonoff theorem, due to Clementino and Tholen. See here for details.
Of course, the notion of being stably closed applies to maps p:XYp: X \to Y besides !:X1!: X \to 1. An analysis of this notion (that the pullback f *p:X× YZZf^\ast p: X \times_Y Z \to Z is a closed map for every map f:ZYf: Z \to Y) leads to the correct notion of proper map in algebraic geometry and elsewhere.
Closely related to closed-projection characterization of compactness, a characterisation of compactness in terms of logical quantification is featured in Paul Taylor's Abstract Stone Duality:
Proposition
XX is compact iff for any space YY and any open subset UU of X×YX \times Y, the subset
XU={b:Y|a:X,(a,b)U} \forall_X U = \{ b : Y \;|\; \forall\; a: X,\; (a, b) \in U \}
is open in YY.
To remove it from dependence on points, we can also write the definition like this:
Definition
XX is compact iff given any space YY and any open UU in X×YX \times Y, there exists an open XU\forall_X U in YY that satisfies the universal property of universal quantification:
V XUX×VU V \subseteq \forall_X U \;\Leftrightarrow\; X \times V \subseteq U
for every open VV in YY.
A dual condition is satisfied by an overt space.
Properties
Various
Proposition
(unions and intersection of compact spaces)
Let (X,τ)(X,\tau) be a topological space and let
{K iX} iI \{K_i \subset X\}_{i \in I}
be a set of compact subspaces.
 1. If II is a finite set, then the union iIK iX\underset{i \in I}{\cup} K_i \subset X is itself a compact subspace;
 2. If all K iXK_i \subset X are also closed subsets then their intersection iIK iX\underset{i \in I}{\cap} K_i \subset X is itself a compact subspace.
Proof
Regarding the first statement:
Let {U jX} jJ\{U_j \subset X\}_{j \in J} be an open cover of the union. Then this is also an open cover of each of the K iK_i, hence by their compactness there are finite subsets J iJJ_i \subset J such that {U j iX} j iJ i\{U_{j_i} \subset X\}_{j_i \in J_i} is a finite cover of K iK_i. Accordingly then iI{U j iX} j iJ i\underset{i \in I}{\cup} \{ U_{j_i} \subset X \}_{j_i \in J_i} is a finite open cover of the union.
Regarding the second statement:
By the axioms on a topology, the intersection of an arbitrary set of closed subsets is again closed. Hence the intersection of the closed compact subspaces is closed. But since subsets are closed in a closed subspace precisely if they are closed in the ambient space then for each iIi \in I the intersection is a closed subspace of the compact space K iK_i. Since closed subspaces of compact spaces are compact it follows that the intersection is actually compact, too.
Proposition
(complements of compact with open subspaces is compact)
Let XX be a topological space. Let
 1. KXK\


text:
In this important volume, Tamara Prosic gives a new explanation of the origins, development and symbolism of Passover.
First, she examines Passover from the diachronic perspective, tracing its development from the period before the centralization of the cult until the second destruction of the temple. Issues with previous scholarship are considered, while at the same time she places the study of Passover within the framework of the new paradigm of historical studies of ancient Israel that advocates the indigenous Canaanitic origin of Israelites.
The second part of the book is synchronic in its approach to Passover and deals with its symbolism. Prosic discusses Passover in biblical legends arguing that the pre-Yahwistic Passover was essentially a rite of passage. From there the investigation moves to symbolic elements of Passover such as time symbolism, space symbolism and symbolism of the sacrifice.
- Examination of Jewish history and historiography
- Outline of the development of Passover symbolism
- All Scripture references are linked to Hebrew texts and English Bible translations in your library
- Title: Development and Symbolism of Passover
- Author: Tamara Prosic
- Publisher: Sheffield Academic Press
- Publication Date: 2005
- Pages: 160
About Tamara Prosic
Tamara Prosic is a lecturer at the School of Historical Studies at Monash University, Australia.


text:
Environment and Climate Change Canada has issued a freezing rain warning for Regina.
Due to a low-pressure system from Alberta, Most of Southern Saskatchewan is expected to be hit with freezing rainfall throughout today.
The freezing rain will begin in the western side of the province this morning and then it'll spread into Regina early this afternoon, then to the Manitoba border by late afternoon.
Some areas under the freezing rain warning including Regina and sections of the Trans-Canada highway will see more than 6 hours of freezing precipitation, creating extremely hazardous travel conditions.
Some areas may see temperatures remain or rise above zero, with will result in just heavy rainfall in those areas instead of freezing rain.
However, travelers should still exercise extreme caution, as the transition to freezing rain and ice-covered surfaces may occur without warning.
Road closures and power outages are highly likely later today.
Surfaces such as highways, roads, walkways, and parking lots will become icy, slippery, and hazardous.
Ice build-up may cause tree branches to break.
Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit, and a flashlight.
The rain is expected to end for most areas this evening.
If you are traveling this afternoon, you can keep up to date on road conditions by visiting the Highway Hotline website.


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Network Testing and Emulation Solutions
Connecting SMA Cables to LANforge
Goal: Connect the antennas of your device under test to LANforge using SMA cables and a fixed attenuator.
Many WiFi testing scenarios benefit from some amount of WiFi isolation. Connecting the radios of the Device Under Test (DUT) to LANforge's radios using SMA cables can improve connection quality. Using a fixed attenuator can reduce a direct signal so that it is heard by the radios without distortion.

 1. The polarities of the cables must match screenshot
 2. Begin by connecting the SMA Female end of the fixed attenuator to the SMA adapter. screenshot
 3. We see that the exposed end of the sma_adapter is RP-SMA-Male. RP means Reverse Polarity. screenshot
 4. Connect the attached attenuator and adapter to the LANforge radio antenna. This exposes the SMA Male end of the attenuator. Your DUT might not have adequate space to mount a fixed attenuator to it, so we suggested connecting it to the LANforge. screenshot
 5. The polarities of the cable end must match the end of the fixed attenuator. The cable end for this side is SMA-Female. screenshot
 6. See how the cable connected to the lanforge has both the adapter and the attenuator. It should be safe to use the attenuator and adapter anywhere along a SMA path. screenshot
 7. Connect the other end of the cable to the Device Under Test (DUT). Your DUT might use different antennas so you might need to use another adapter. screenshot
 8. We have connected one antenna of our DUT to the one antenna of our LANforge. Repeat this for multiple antennas. screenshot
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text:
The New York Stock Exchange requires that boards of listed companies conduct a self-evaluation at least annually, and research suggests that well-run boards take this process quite seriously, often using a combination of director surveys and personal interviews to assess the functioning and effectiveness of the board, its committees, and its individual members.
As boards prepare for their next round of self-evaluation, they will want to use the opportunity to assess their capabilities and readiness to govern in the wake of Covid-19. Below are some topics and items they may want to consider adding to their survey instruments or interview protocols based on my analysis in the companion article to this list.
The content and structure of board self-evaluation instruments vary enormously. The list below need not be used in its entirety and individual items can be adapted as needed to fit whatever format and structure is desired. The items are presented as statements for which directors are asked to express their agreement or disagreement on a numeric scale. They can be used selectively and added to an existing survey or interview protocol as appropriate.
More Attention to Stakeholders
1. As a director, I have a clear understanding of the company's purpose and responsibilities to each of its core stakeholder groups.
2. The annual or multi-year goals and targets reviewed by the board include goals related to creating value for each of the company's core stakeholder groups.
3. In developing and reviewing strategy, the board gives due consideration to potential impacts of its decisions on the company's different stakeholder groups.
4. The board is provided with analyses of how potential mergers and acquisitions will likely impact the company's different stakeholder groups.
5. The company's reporting and disclosure practices meet the needs of its various stakeholder groups.
6. The board's level and frequency of engagement with each of the company's stakeholder groups is appropriate.
More Attention to How Business and Society Interact
1. The board includes members with the ability to take a public interest perspective.
2. As part of risk oversight, the board pays sufficient attention to risks arising from large-scale environmental and societal problems.
3. To inform its review of strategy, the board receives adequate information on large-scale societal and environmental trends that may present risks and opportunities for the company.
4. In discussing strategy, the board devotes adequate time to understanding the impacts on the environment and society-at-large.
5. In reviewing budget and capital allocation decisions, the board considers the potential environmental and social impacts of these decisions.
6. The board regularly receives information and analyses of the company's social, environmental, and other impacts, both positive and negative, on society at large.
7. The board oversees the company's civic and political engagement policies and activities.
More comprehensive approach to compensation
1. The board pays attention to the company's pay policies and practices across the organization (and not just to executive pay).
2. In reviewing and approving the company's pay policies and practices, the board devotes sufficient attention to considerations of fairness, especially toward the lowest-paid employees and those who are members of minority or historically disadvantaged groups.
3. In reviewing and approving the company's executive compensation program, the board is provided with sufficient information and analyses to assess the fairness of likely payout amounts to executives relative to their contributions, relative to the payouts to other employees, and relative to returns to shareholders.
4. In reviewing and approving the company's executive compensation program, the board pays sufficient attention to ensuring alignment with the company's strategic objectives, including its diversity and inclusion goals, and its societal and environmental commitments.
5. In reviewing performance for purposes of awarding compensation, the board pays appropriate attention to the company's social and environmental performance, including negative impacts on third parties and the environment, as well as to its financial performance.
6. The mandate of the board's compensation committee is sufficiently broad to cover the expanded set of issues that it needs to address in the post-Covid era.
7. The compensation committee's report to shareholders addresses issues of fairness, including toward minority and historically disadvantaged groups, and explains the relation of pay to the company's strategic priorities and social and environmental performance.
More Deliberative Decision-Making
1. The board devotes adequate time to discussing difficult or controversial issues.
2. The board is provided with the information and analyses it needs to make sound decisions.
3. The board chair invites directors with opposing or minority views into the discussion.
4. The board chair ensures that opposing views are considered even when the directors themselves are in agreement.
5. The board chair ensures that decisions are considered from differing perspectives, including those of different stakeholders, differing racial and ethnic groups, and the general public.
6. The board chair ensures that the board pays adequate attention to alternative future scenarios in making decisions with long-term implications.
7. The board chair is effective in guiding the board's deliberations to a conclusion without imposing his or her views.
8. This board is able to engage in serious debate without undermining its members' ability to work together.
9. The board's process for deliberating and making decisions leaves directors with a clear understanding and ability to explain the rationale for the decisions taken.
More Attention to Board Composition and Director Race and Ethnicity
1. All members of the board, whatever their gender, race, or ethnicity, feel that their contributions are respected and valued.
2. The board considers racial and ethnic diversity in constructing the skills and experience matrix used to assess its composition.
3. In searching for new directors, the board actively seeks candidates from different racial and ethnic groups.
4. In interviewing candidates for director openings, the board regularly interviews one or more candidates from an underrepresented group.
5. In selecting new directors, the board screens for openness and inclusiveness toward individuals of different races and ethnicities.
6. The process of bringing new directors into the board is designed with racial and ethnic differences in mind.
7. The board's culture is welcoming to individuals of different racial and ethnic backgrounds.
8. The board has a robust process for overseeing management's diversity and inclusion efforts.
9. The board understands the business impacts of fostering a diverse, equitable, and inclusive workplace.
A More Demanding Job
1. I have a clear understanding of my role and responsibilities as a director.
2. The board as a whole has a shared understanding of its role and responsibilities.
3. The board receives the information and analyses that it needs to fulfill its responsibilities.
4. The number and cadence of board meetings and other board interactions is sufficient for the board to fulfill its responsibilities.
5. Even with the expanded time commitment and responsibilities associated with Covid-19, I have sufficient time to carry out my work and fulfill my responsibilities as a director.


text:
Annual income for women in Ireland is around 70% of that earned by men, even though women are less likely to leave school early and more likely to have gone to college.
The CSO's Women and Men in Ireland 2010 points out that more than half of women aged 25-34 have a third-level qualification, compared with 39% of men in the same age group.
In 2009 the early school leavers rate among women aged 18-24 was 8.2%, much lower than the rate among men at 14.4%.
The report shows that women's income in 2008 was around 70% of men's income but, after adjusting for the longer hours worked by men, women's hourly earnings were around 90% of men's.
There were 863,000 women and 996,100 men employed in Ireland last year with the education and health sectors employing the highest proportion of women.
Just over one fifth of the women employed in clerical and secretarial occupations, compared with only 6% of men.
Craft and related occupations were the least gender-balanced with men representing 95% of workers in this category while professional occupations were the most gender balanced, where 51% of those at work were women.
In the health sector 80% of employees are women while in primary education, 83% are women and at second-level 64% are women.
But women are not well represented at senior level positions in the education and health sectors — only 34% of medical and dental consultants are women; 54% are primary school managers and 39% are second-level school managers.
While men have a high rate of employment, they also have a higher rate of unemployment but the proportion of men and women at risk of poverty in 2009 was the same for both sexes at 14%.
The employment rate for men in Ireland stood at about 75% over recent years but in 2009 it plummeted to 67.3% and dropped again in 2010 to 64%.
The EU target rate for women was 60% by 2010, a target that was met by Ireland in 2007 and 2008 but not in 2009 or 2010, when the rate had fallen to 56.4%.
Last year 46% of those in employment were women. Men worked an average of 39.4 hours a week last year, compared with 30.9 for women. The annual unemployment rate for men in Ireland was about 5% when the economy was buoyant. In 2009 it increased sharply to 15.1% and rose again in 2010 to 16.7%.
The unemployment rate for women, that stood at about 4% before the economic downturn increased in 2009 to 8.1% and rose again in 2020 to 9.8%.
For the 20-24 age group, 32.9% of men and 18.7% of women were unemployed in 2010.
The report also shows that women are under-represented in decision making at both national and regional levels. Last year just 14% of Dáil members were women, while the average female representation in national parliaments in the EU was nearly a quarter.
Women account for just over a third of members of state boards, less than a fifth of members of local authorities and just over a third of the membership of vocational education committees.
Life expectancy for women in Ireland was 81.6 years in 2006, nearly five years more than men at 76.8 years , however, is just over half a year more than the 2007 EU average, while for women it was a half year less.
Across the industrialised world women live between five and 10 years longer than men and one reason is that women develop cardiovascular disease about 10 years later than men, usually in their 70s and 80s. It is also thought that the reason is genetic.
Other reasons why men die at an earlier age than women is they smoke more, although that gender gap is shrinking, and eat more food that leads to high cholesterol. Also men tend not to deal with stress as well as women and stress plays a very important role in cardiovascular disease.
IRELAND had 98 men per 100 women in the population in 2010.
Emigration has risen steeply in the last four years, especially for men, with 25,100 men and 9,400 women leaving the country last year.
The labour force participation rate for men was highest for the 35-44 age group, at 92% last year.
Almost three-quarters of men in employment worked for 30 or more hours a week in 2010, compared with 58% of women.
Nearly 41% of married men worked for 40 or more hours in paid employment per week, compared with 13% of married women.
70% of persons describing themselves as retired in 2010 were men.
Men had an average income of €35,966 in 2008, while the average income for women was €25,077.
Men outnumbered women in all national and regional decision-making structures in Ireland last year. The mortality rate due to accidents for men was more than twice that of women in 2009, with the rate of male deaths due to suicide nearly four times the female rate. Male rate for admission to psychiatric units for schizophrenia was nearly two-thirds higher than the female rate.
AVERAGE age of birth of first child increased from 25 years in 1980 to 29 in 2009.
Women more likely have a stay in hospital, with one-sixth of hospital stays pregnancy and childbirth-related.
Over half a million women were looking after their home and family last year, compared with only 7,500 men. Over 10% of the 10,865 persons jailed in 2009 were women.
Between 2000 and 2010 the employment rate for women aged 55-64 increased from 27% to 43%, but still below the 50% Stockholm Council 2010 target.
Only 10% of women employed in agriculture, forestry and fishing are women, compared to over 38% in the EU.
Women represented four-fifths of persons who worked up to 29 hours per week in paid employment in 2005 and three-quarters in 2010.
The number of women living as lone parents increased by 46%, from 93,800 to 137,100 over the period 2000-2010.
Almost 98% of the 90,485 persons in receipt of one-parent family payments in 2009 were women.
Female rate of admission for depressive disorders was over one-third higher than the male rate.


text:
While it may not seem significant at first, sexing your pet crested gecko is actually important from the point of view of not just breeding but also potential cohabitation and dietary requirements.
Plus, isn't it actually interesting to know what sex your pet crested gecko is?
Here, we look at how to sex your crested gecko and why.
Why Sex Your Crested Gecko?
Sexing your crested gecko will play an important role in your plan ahead as a pet owner in terms of breeding, cohabitation, and diet of your pet crested gecko.
While most other fundamental needs of crested geckos are pretty much the same regardless of their sex, things like whether or not you should let your crested geckos cohabitate will depend heavily on their sex.
Reason 1 – Breeding
If you want to venture into the arena of breeding your crested geckos, the first and foremost thing you will need to know is the sex of your crested geckos.
You will, by default, need one of your crested geckos to be a female, while the other, be a male. And the only way of knowing which one is which, will be by knowing how to sex your crested geckos.
Reason 2 – Cohabitation
Some pet owners of reptiles, especially species like the crested gecko, are interested in letting their pets cohabitate. If you happen to be one of those, then it is pertinent for you to know the sex of your crested geckos.
You can never house two male crested geckos in the same enclosure. It will always lead to fights over territory and resources. Both of your crested geckos will end up harming and injuring each other.
On the other hand, you can easily house two or more female crested geckos in a single enclosure, provided that the enclosure is big enough for all the crested geckos to have their own spots for warming up, cooling down, eating, drinking water, etc.
You can house a male and a female crested gecko, but you will need to monitor them consistently and regularly.
It is obvious that in such a pairing, mating will become a regular activity. But you will need to ensure that the male crested gecko does not bully the female crested gecko or show physical aggression towards her.
So, cohabitation needs a lot of planning and monitoring. And the first step in it is to know the sex of your crested geckos.
Reason 3 – Diet Planning
Your female crested gecko will need a diet that is denser in nutrients, especially calcium. Female crested geckos lay eggs with or without mating.
It is a part of their normal bodily cycles. The eggs laid without mating are naturally infertile. Nevertheless, it takes a toll on the calcium reserves in the body of the female crested gecko.
This makes female crested geckos more prone to developing fatal illnesses like metabolic bone disorder.
Knowing the sex of your crested gecko will therefore allow you to make more informed choices about the diet of your pet.
4 Ways of Sexing Adult Crested Geckos
The first and foremost thing you need to do before sexing your crested gecko is to wait until the right age.
While you can differentiate between the two sexes of crested geckos as early as 4 months of age, you should hold off the sexing process until your crested gecko is at least 6 to 9 months old.
This is because regardless of the method you use to sex your crested gecko, it will require you to handle your pet.
And it is highly recommended that you do not handle your pet until it is at least 6 months of age – younger crested geckos tend to be more skittish and physically weaker. So, when held, they may suddenly jump off your hand and injure themselves by landing improperly on a hard surface.
That being out of the way, there are 4 ways of sexing adult crested geckos:
Identifying the hemipenal bulges.
This is the easiest way of sexing your crested gecko – and it requires the least handling.
All you have to do is either hold your crested gecko a little above your head or place it in a clear and transparent bowl or container. Then, with a torch, visually inspect the region near its vent and at the base of its tail.
If your crested gecko has bulges in that region, then it is a male crested gecko. Those bulges are the bubble-shaped cloaca in which the male crested geckos keep their two hemipenes stored until it is time to mate.
If there is no hemipenal or bubble-shaped bulge near the vent, your crested gecko is very likely a female.
Identifying the pre-anal pores.
This is another way of identifying the sex of your crested gecko. In a fashion similar to the one mentioned above, you will need to either hold your crested gecko high up or place it in a clean and transparent bowl or container.
Carefully observe the region just above your crested gecko's vent, between its legs. If you notice a small, horizontal line of pores that are barely visible, your crested gecko is a male.
These pores will allow your crested gecko to secrete pheromones to attract female crested geckos when it is time to mate.
If, on the other hand, there is no such line of pores visible, your crested gecko is a female.
Size of the body and the head.
This is more of a confirmatory process than an actual standalone way of sexing your crested gecko. If, by using the two aforementioned ways, you have clarity about the sex of your crested gecko, then inspecting the general size of the body and head of your pet will allow you to confirm your findings.
As is the case with most animals, the male crested gecko will be larger and broader in size when compared to a female crested gecko.
Talk to a vet with expertise in crested geckos.
When all else fails and you are still unsure or unsatisfied with your findings, you should turn to a professional with experience. Talk to the vet of your crested gecko and they will be able to find out the sex of your pet for you.
They won't exactly use any different methods – they will just have a keener eye and all the necessary tools required for hassle-free sexing of your crested gecko.
Is Crested Gecko Gender Temperature-Dependent?
No, the gender of a crested gecko is not temperature-dependent.
A common misconception that floats around a lot is that if you incubate the eggs of a crested gecko at a higher temperature, you will get more males as opposed to females at lower temperatures.
That is untrue. The temperature of the incubator is important for the health of your crested gecko eggs – but they do not determine the gender of the hatchlings.
So, never increase or decrease the temperature of your crested gecko's incubator beyond the thresholds. The ideal temperature for the incubator is between 70 and 80 degrees Fahrenheit.
Can a Crested Gecko Change Its Gender?
No, a crested gecko cannot change its gender. The gender of a crested gecko, much like the gender of most animals, is determined at birth and remains the same for the rest of its life.
What can cause confusion, however, is sexing a crested gecko when it is still very young. Some breeders and sellers may make false claims about selling male or female crested gecko hatchlings or babies.
You should not fall for those claims because the sex of a crested gecko can only be confirmed after your crested gecko reaches an age of 9 or 10 months.
So, if you bought a female baby crested gecko, but are now realizing that your crested gecko is actually a male – your pet hasn't changed its gender. It was never a female crested gecko, to begin with.
How Old Does My Crested Gecko Need To Be?
In order for you to sex your crested gecko accurately, your pet needs to be at least 9 to 10 months old.
What Size Can You Sex A Crested Gecko?
You can sex a crested gecko when it is roughly 6 to 9 inches in size and weighs somewhere between 16 and 35 grams.
Sexing your crested gecko has numerous benefits in terms of cohabitation, breeding, and diet planning. Knowing how and when to sex your crested gecko will help you know the gender of your pet accurately.
Do not fall for false claims of the sex of crested geckos by breeders or sellers who claim to sell baby female or baby male crested geckos.
The sex of a crested gecko can only be accurately identified when it is around 9 months of age, 6 to 9 inches in size, and somewhere between 16 to 35 grams in weight.