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Projection-based model order reduction for aerodynamic applications
GND
_PHONE_
Affiliation/Institute
Institut Computational Mathematics
Vendl, Alexander
The subject of this thesis is model order reduction for the governing equations arising in computational fluid dynamics (CFD). Although the application of numerical simulations gains in importance compared to experimental wind tunnel tests, the large amount of time needed for the vast number of computations limits the applicability. As a result efficient computational methods, such as model order reduction, play an important role. The goal of model order reduction is to reduce the number of equations of the underlying system. The reduced order model should then have the property that it can be solved much more efficiently. The challenge of the application to nonlinear equations like the governing equations of CFD is that, although the number of discretized equations can easily be reduced by projection, an independence from the full order is not actually achieved. This is due to the fact that in each iterative step of solving the reduced model, a nonlinear right hand side has to be evaluated, which is of the order of the original model. As a result nonlinear model order reduction methods aim at creating reduced order models, which do not evaluate the right hand side of the governing equations at each and every computational grid point, but only at a small subset of these points. In this work a method called missing point estimation is used. It achieves the above goal with an appropriate projection. Furthermore, due to the projection onto a low-dimensional subspace, the number of equations is significantly reduced compared to the original problem. This altogether yields a reduced order model, which can be solved efficiently. When applying missing point estimation to different fields of application, the selection of the points differs considerably. In this work it shall be investigated, which point selections are most suitable for the prediction of the flow fields around airfoils and complex three-dimensional aircraft configurations.
Diese Arbeit hat die Modellreduktion der Grundgleichungen der Strömungsmechanik zum Thema. Obwohl der Einsatz der numerischen Strömungssimulation gegenüber experimentellen Tests im Windkanal an Bedeutung gewinnt, schränkt der hohe zeitliche Aufwand für die große Anzahl der benötigten Berechnungen die Anwendbarkeit ein. Daher spielen effiziente Berechnungsmethoden wie die Modellreduktion eine wichtige Rolle. Die Modellreduktion hat zum Ziel, die Anzahl der Gleichungen des Systems zu reduzieren. Das Modell reduzierter Ordnung sollte dann die Eigenschaft haben, dass es sich deutlich effizienter lösen lässt. Die Herausforderung bei der Anwendung auf nichtlineare Gleichungen wie denen der Strömungsmechanik besteht darin, dass obwohl die Anzahl der Gleichungen durch Projektion stark reduziert werden können, keine Unabhängigkeit von der Ordnung des Ausgangsproblems erreicht wird. Dies liegt daran, dass in jedem Schritt zur Lösung des reduzierten Modells die rechte Seite des ursprünglichen Systems ausgewertet wird, die von der Ordnung des Ausgangsproblems ist. Daher ist das Ziel, reduzierte Modelle so zu erstellen, dass die rechte Seite nicht an jedem Punkt des Rechengitters, sondern an einer Teilmenge dieser Punkte ausgewertet wird. In dieser Arbeit wird eine Methode namens Missing Point Estimation (MPE) verwendet, die das obige Ziel mit Hilfe einer geeigneten Projektion erreicht. Aufgrund dessen, dass auf einen niedrig-dimensionalen Unterraum projiziert wird, ist zudem die Anzahl der Gleichungen stark gegenüber derjenigen des Ausgangsproblems reduziert. Dies hat dann insgesamt zur Folge, dass sich das reduzierte Modell effizient lösen lässt. Bei der Verwendung der MPE für unterschiedliche Anwendungsgebiete ist die Auswahl der Punkte, an denen die rechte Seite des Systems evaluiert wird, sehr verschieden. In dieser Arbeit soll untersucht werden, welche Auswahlen sich für die Vorhersage von Strömungen um Tragflächenprofile und um komplexe 3D-Konfigurationen eignen.
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text:
Medal of Science
President John F. Kennedy awarded the first National Medal of Science on February 18, 1963 to Theodore von Kármán for his leadership in science and engineering basic to aeronautics. Von Kármán was also cited for his effective teaching, contributions in many fields of mechanics, counsel to the Armed Services, and for his promoting international cooperation.
Since its creation by Congress in 1959 as part of Public Law 86-209, the National Medal of Science has honored individuals "deserving of special recognition by reason of their outstanding contributions to knowledge in the physical, biological, mathematical, engineering, chemistry and social sciences." Four decades later, more than 400 of America's scientists, thinkers, and discovers have been honored with this medal.

source: HuggingFaceFW/fineweb-edu


text:
Pelvic clock in different contexts
Sitting on the chair
- Sitting on the chair, feet firmly on the floor, knees separated as you feel supported and if you are supported on Ischia. Put one hand under your buttocks to feel the shape of the bony protuberance (ischial tuberosity). Take my hand take a reference on the wall, a point where your eyes naturally tend to rest.
- Very slowly move your pelvis and becomes small rounding the back and returns to the center. When you move do not hold your breath, it makes the legs, abdomen, chest, shoulders and neck are relaxed.
- Tilt your pelvis and slowly arching the lower back by venting the stomach. Exhale, relax the back and legs. Feel how the weight moves forward on Ischia, the trunk extends to become erect. Continue to slowly tilt your pelvis tilting forward and back arching and rounding your back.
- Yet sit in the chair. With both feet on stable ground, hands on thighs, the pelvis tilts toward the left knee so that the weight moves to the left buttock and the right bar is raised a bit 'from its support. Feel like your right shoulder is progressing slowly moves back and the left and the right side tends to rise, the coast side of this approach, the column is extended and the head moves to the left accompanied by the look.
- Now tilt your pelvis toward your right knee feel like eyes are moving, how they organize the head, ribs, hips and knees as you move the weight on the buttocks and feet. Leaves the body soft and relaxed so that breathing can take place freely.
- Imagine that the chair is painted on the support and draw a clock with the dock 12-6 H, then from 3 to 9 H, and finally draws every hour intermediate describing circles in one direction and then in the total involvement in the body movement.


text: High industrial demand and limited global abundance of precious metals (PMs) make their recycling essential for industrial and societal sustainability. Owing to their high surface-to-volume ratio, recycling of nanoparticulate precious metals through dissolution in dilute acids at room temperature is quite relevant. However, their dissolution by approaches such as the cyclic oxidation-reduction of metal surfaces through surface potential manipulation may not be suitable for large-scale production. Here, we demonstrate fast dissolution of Pt-nanoparticles under mild conditions (normal temperature and pressure) in Cl- containing dilute acidic/neutral baths without using cyclic oxidation-reduction. We demonstrate that the dissolution of Pt nanoparticles through [PtClx]2- complexing is hindered by blockage of the Pt surface due to adsorption of non-oxide species (impurities), a phenomenon termed herein as non-oxide passivation (NOP). The nanoparticles can be kept active for the [PtClx]2- complexing through removal of the adsorbed species by surface activation, a process to remove the NOP layer by application of cyclic/continuous perturbation. As an example, average % dissolution rate (calculated on initial Pt loading) increases from ∼10% per h (∼30% dissolution in 3 h) for dissolution without NOP removal to ∼19% per h (∼55% dissolution in 3 h) for dissolution through cyclic activation of the Pt surface by HCl-water cycling. The approach may be implemented with a range of cost-efficient and non-toxic reagents for industrial-scale and environmentally friendly recycling of Pt.

source: m-a-p/FineFineWeb


text:
What does TIME mean in Unclassified?
This page is about the meanings of the acronym/abbreviation/shorthand TIME in the Miscellaneous field in general and in the Unclassified terminology in particular.
Find a translation for TIME in other languages:
Select another language:
What does TIME mean?
- time, clip(noun)
- an instance or single occasion for some event

source: openbmb/Ultra-FineWeb


text:
Produksi Ujaran Siswa Autis
Studi Kasus di SMA Lazuardi GIS Depok
This study is aimed to determine the speech production in students with autism at Lazuardi GIS Senior High School, Depok. The study is focused on speech production in students with autism in order to have knowledge of the structure and the type of sentences given by students with autism. This research was conducted in Lazuardi GIS Senior High School, Depok in August 2016. This study is formed with a qualitative case study method. The data of this study were collected by conducting a direct observation of speech production activity in students with autism. This involved multifaceted interviews for studies conducted to teachers, friends, and families of students with autism. To be included, all findings are recorded on a sheet of field observations and recording devices. The data for this study are analyzed in the form of the table and also had a described analysis. The speech result of students with autism had been qualified to be a complete sentence consists of a subject and predicate. In addition, the study was found that speech does not have an element of predicate as forms an incomplete sentence. Out of 59 utterances that have been collected, the study had most commonly found utterance directive, as total 32 utterances. As many as 20 representative utterance speech in total, and the study also found the 7 commissive speeches. Moreover, the study did not found the form of expressive and declarative speeches. This is because the students with autism are not able to control their basic emotions in speech production. This resulted in the conclusion, that students with autism utterances produced by the age of 18 years old has become a communicative speech, in which contained messages that could be understood by the other speaker even though the sentence is not complete.
How to Cite
ALBAB, Suhfi. Produksi Ujaran Siswa Autis. UHAMKA Graduate School Thesis Abstract Collection, [S.l.], v. 2, july 2018. Available at: . Date accessed: 20 nov. 2018.
Pendidikan Bahasa Indonesia/ Indonesian Education


Qt.
- core-image-rt: This is a core-image-minimal image plus a real-time test
suite and tool appropriate for real-time use.
- core-image-rt-sdk: This is a core-image-rt image that includes a
complete standalone SDK and is suitable for development using the target.
- core-image-sato: This is an image with Sato support and a mobile
environment for mobile devices that use X11; it provides applications such as
a terminal, editor, file manager, media player, and so forth.
- core-image-sato-dev: This is a core-image-sato image that includes
libraries needed to build applications on the device itself, testing and
profiling tools and debugging symbols.
- core-image-sato-sdk: This is a core-image-sato image that includes a
complete standalone SDK and is suitable for development using the target.
- core-image-multilib-example: This is an example image that includes a
lib32 version of Bash, otherwise it is a standard Sato image.
[ 18 ]
Chapter 2
The up-to-date image list can be seen in the Yocto Project Reference Manual.
The process of building an image for a target is very simple. We must run the
following command:
$: bitbake <recipe name>
For example, to build core-image-full-cmdline, run the following command:
$: bitbake core-image-full-cmdline
We will use MACHINE = "qemuarm" in the following examples. It
should be set in build/conf/local.conf accordingly.
Running images in QEMU
As many projects have a small portion that is hardware dependent, the hardware
emulation comes to speed up the development process by enabling sample to run
without involving an actual hardware.
Quick EMUlator (QEMU) is a free and open source software package that performs
hardware virtualization. The QEMU-based machines allow test and development
without real hardware. Currently, the ARM, MIPS, MIPS64, PowerPC, and x86 and
x86-64 emulations are supported.
The runqemu script enables and makes the use of QEMU with the OpenEmbeddedCore supported machines easier. The way to run the script is as follows:
$: runqemu <machine> <zimage> <filesystems>
Here, <machine> is the machine/architecture to be used as qemuarm, qemumips,
qemuppc, qemux86, or qemux86-64. Also, <zimage> is the path to a kernel (for
example, zimage-qemuarm.bin). Finally,<filesystem> is the path to an ext3 image
(for example, filesystem-qemuarm.ext3) or an NFS directory.
[ 19 ]
Baking Our Poky-based System
So, for example, in case we run runqemu qemuarm core-image-full-cmdline, we
can see something as shown in the following screenshot:
We can log in with the root account using an empty password. The system behaves
as a regular system even being used inside the QEMU. The process to deploy an
image in a real hardware varies depending on the type of storage used, bootloader,
and so on. However, the process to generate the image is the same. We explore how
to build and run an image in the Wandboard machine in Chapter 14, Booting Our
Custom Embedded Linux.
Summary
In this chapter, we learned the steps needed to set up Poky and get our first image
built. We ran that image using runqemu, which gave us a good overview of the
available capabilities.
In the next chapter, we will be introduced to Hob, which provides a human friendly
interface for BitBake, and we will use it to build an image and customize it further.
[ 20 ]
Using Hob to Bake an Image
Hob is a human friendly interface for BitBake. It helps us customize images and have
them the way we want. It also enables us to run the image on QEMU after bitbaking
it. It is just like a bakery display; we can pick what we want and use it right away.
Building an image using Hob
Our first step is to set up our build environment, as follows:
$: source poky/oe-init-build-env [build-directory]
We can choose an old build directory or create a new one.
Now, Hob is ready for use. To start it, we should run the following:
$: hob
At startup, Hob performs some parsing tasks, reading the local configuration
and available metadata layers. After a short time, Hob proposes a list of available
machines. We can select, for example, qemuarm.
Once the dependency tree is built, select the desired image, for example, coreimage-full-cmdline.
Using Hob to Bake an Image
The following screenshot shows the MACHINE variable content and the image to be
built in the Hob interface:
With the target MACHINE and image selected, the next step is to choose some
advanced configuration, such as image types (for example, cpio.gz, ext2.bz2,
ext3.gz, jffs2, ubifs, and vmdk) or package formats (rpm, deb, IPK, or TAR). We
can also exclude all packages under the GPLv3 licensing, as shown in Chapter 13,
Achieving GPL Compliance.
From the upper-right hand corner of the window, we can access the two areas
Images and Settings. Images offers access to the built images (from the past),
and Settings performs changes to MACHINE, parallelization, distribution, shared
folders, and BBLAYERS. Hob modifies the build/conf directory contents inside our
build directory. We can use Hob on our already configured build folder, and all
configurations are reflected on Hob. It may be very useful when working on a team.
If we are working to configure the shared environment for a team, we need to pay
attention to the variables DL_DIR and SSTATE_DIR, which are detailed in Chapter 4,
Grasping the BitBake Tool, and Chapter 6, Assimilating Packaging Support.
[ 22 ]
Chapter 3
If we plan to build a standard image, we can click on Build Image and wait for
BitBake to run the required tasks to build it. Otherwise, if we want to change the
recipe set of an image, we can click on Edit image recipe.
Customizing an image with Hob
The following screenshot shows the list of included recipes in the Hob interface:
We can add or remove recipes (there is a search box in the upper-right hand corner)
by selecting or deselecting them. If we click on the recipe name, we can see details
such as its version and license.
[ 23 ]
Using Hob to Bake an Image
From the tabs, we can see the number of selected packages, the list of available
packages, and how the selected packages are grouped, as shown in the
following screenshot:
After clicking on Build packages and waiting for them to be built, we have a second
chance to see the list of selected packages, to know the value of the Estimated image
size, and to decide to remove some application in order to generate a smaller image.
By clicking on the package name, the included files from this package are listed. If a
package is highlighted, its log can be displayed by clicking on Open log.
BitBake resolves all dependencies from the selected packages, including any needed
additional package.
We can wrap the image by clicking on Build image and waiting until our image is
ready, as shown in the following screenshot:
[ 24 ]
Chapter 3
We can start over and change configurations, edit the selected packages, view logs,
or list the files. Or, for images made for the QEMU-based machines, we can click on
Run image and see our image being run inside the QEMU emulator, and the Yocto
Project logo, as shown in the next screenshot:
[ 25 ]
Using Hob to Bake an Image
Hob is a nice tool for image adjustments and addition of few packages on existing
images. It is a great user-friendly interface for simple tasks and may be useful for
teams to make temporary modifications in their images.
Hob is in the process of being replaced by a new tool called Toaster.
At the time of writing this book, Toaster is under heavy development,
and it is still feature incomplete. However, the next Yocto Project
release will supersede Hob, according to the Toaster planned feature
set. So, it is advised to research for Toaster in the Yocto Project
documentation website for more updated information.
Summary
In this chapter, we learned about the different Hob functionalities and configurable
variables. We learned how Hob can be used to easily make changes by teams and
how it takes advantage of a user-friendly user interface for simple tasks.
In the next chapter, we will understand how BitBake does its magic. We will grasp
the parsing, preferences and providers support, dependencies, task handling, and
main task functions.
[ 26 ]
Grasping the BitBake Tool
We now start our journey to understand how the Yocto Project's engine works
behind the scenes. In the preceding chapters,


Putting curing lights in the spotlight
May 9, 2019
Terri Lively
Curing lights are often considered the supporting cast for restorative materials, but learn why they're a vital component of a restoration's success.
Light curing units (LCU) are essential for the successful polymerization of direct composite restorations. However, they're rarely in the spotlight and, many times, considered supporting cast for the features and benefits of the material itself.
Let's take a closer look at why LCUs are vital for a direct composite restoration's success, the types of curing lights available, and what you can do to get the most out of your LCU and keep it optimized for proper curing.
Polymerization is crucial for composite materials. When polymerization isn't sufficient, it reduces the strength of the restoration. Insufficient polymerization also results in water absorption, increased solubility of the composite and reduced hardness of the cured material.1
Related reading: Is your curing light 'bright' enough?
The curing light used has a vital role in polymerization. Per the Journal of Clinical and Experimental Dentistry, some ways the light affects the polymerization process include:2
 - The duration of radiation
 - Where the tip of the curing light is pointed in relation to the composite and how far it is from it
 - The wavelength and bandwidth of the light's output
 - The intensity for the light
 - The irradiation time
Your LCU works with the photoinitiator in the material to activate the polymerization process. According to Spear Education, there are three types of photoinitiators: camphorquinone (CPQ), phenyl-propanedione (PPD), and trimethylbenzoyl-diphenyl-phosphine oxide (TPO).3
Most composite materials use CPQ as the light-sensitive component.4 The activation and performance of CPQ require the LCU to have the proper intensity with the highest assimilation wavelength range of CPQ. If your LCU falls short on either intensity or wavelength, you can compromise the strength and longevity of your direct composite restoration.5
The ISO 4049 Standard is the International Organization for Standardization's recommendation for the intensity and wavelength of curing lights. These standards are:6
 - An intensity of 300 mW/cm2
 - A wavelength bandwidth of 400-515 nm (on the tip of the device)
 - A depth of cure minimum of 1.5 mm
 - Five generations of curing lights
An LCU is a significant factor in the success of a direct composite restoration. Over the years, LCUs have changed a lot, improving power, reducing size and increasing efficiency.
Per the IOSR Journal of Dental and Medical Sciences, there have been five generations of curing lights since the 1970s, including:7
 - Ultraviolet light (no longer available)
 - Visible light curing units: quartz-tungsten halogen (QTH) lights fall into this category
 - Plasma arc curing units (PAC)
 - Light-emitting diodes (LED)
 - Argon lasers
The first curing lights were ultraviolet lights. However, these weren't effective enough for curing composite because of the short wavelength that put limitations on the depth of cure. Moreover, they used ultraviolet light, which has other hazards to the patient.8
The second generation of curing lights appearing in the early 1980s were the visible light curing units. These replaced the ultraviolet lights and led to a few developments over the next 20 years, such as using blue light to initiate polymerization, developing the quartz-tungsten halogen bulb (QTH) and increasing the intensity of the light to ensure a greater depth of cure.9
More from the author: 5 mistakes you might be making with composites
The late '90s presented the third generation of curing lights with the plasma arc curing light (PAC), which used a fluorescent bulb that contained plasma. PACs were fast, curing the composite material in three to five seconds.10
Light-emitting diodes (LED) emerged in the 2000s and were the fourth generation of curing lights. LEDs have long lifetimes and require no filters to produce the blue light. They also have a more concentrated bandwidth than their predecessors.11
Finally, the fifth generation of curing lights are argon lasers. First introduced into dentistry in the early 1990s, dental professionals began using argon lasers to cure composite because the wavelength enhances the thorough cure and physical properties of the material when compared with the polymerization and physical properties produced by other types of curing lights.12
Dr. John Flucke, technology editor for Dental Products Report, explains that curing lights had significant advances in the 2000s. LCUs decreased in size and changed to "toothbrush-style" units, which Dr. Flucke says make it easier to access challenging areas in the oral cavity, particularly in the posterior.13
Dr. Flucke prefers the LED lights over all the others for a few reasons. First of all, their wavelength is efficient for CPQ photoinitiator. Second, they're energy-efficient, and they use less electricity, which means they don't need AC. These battery-powered units take up less space in the operatory, and they're also cordless and environmentally friendly. In addition, many of the LED lights allow you to change the wavelength of the curing light, which means you can change the wavelength if you have a different photoinitiator than CPQ.
Tips for getting the most out of your LCU
LED lights are smaller and located on the curing head, making them optimal LCUs for curing direct restorations at the proper distance. Dr. Flucke recommends keeping the light as close and parallel to the direct restoration as possible. Even moving it a few millimeters away from the composite decreases the efficiency the LCU, which can result in inadequate curing for the restoration.
Dr. Gary DeWood, a Spear Education faculty member, recommends when using an LED light to cure a direct composite restoration to move it continuously during the cure.14 LED lights don't have a homogenous spread from the tip, which affects the cure pattern of the composite. Moving it ensures that the material will cure appropriately. However, since it changes the distance of the tip from the material, Dr. DeWood says it also means you should add additional time to the process to allow for an adequate cure.
Dr. Ed Kusek, a private practice dentist in Sioux Falls, South Dakota, encourages doctors to take care of their curing light. He also suggests putting a shield over it when in use.
Trending article: Dental care in paradise
"We always put a shield over the top of it. If we're putting it close to the mouth or the restoration, they don't get any bonding agent on the lamp portion," Dr. Kusek says.
Dr. Kusek also advises that if the assistant has the light, the doctor should ensure he or she gets in the right spot. If the light is shaking or too far away, the LCU can't do a good job of curing.
For Class II restorations, Dr. Kusek says you need to cure it on the buccal and lingual molar side to ensure the cure is adequate. When the cure isn't suitable, you begin to have problems with your restoration.
"It will start breaking down much faster. If the inner portion doesn't cure as it should, the margins will break away, and then you have recurrent decay, and the restoration will fail," Dr. Kusek explains.
To avoid failure, Dr. Kusek thinks the bond is essential. He always puts two layers of the bonding agent. He says he was lucky enough to do some studies with bonding and although there are plenty of decent options available, the study proved to him that Peak™ Universal Bond (Ultradent) is the best bonding agent.
"Peak has a filler agent to it. The bond strengths are one of the highest on the market, so it will take the pounding in posterior areas or the anterior," he says.
Because of the strength requirements, Dr. Kusek says he puts two layers on and then a thin layer of flowable to reduce the shrinkage value. Finally, he either uses a bulk fill composite or layered composite.
Maintenance is crucial
Today, LEDs and QTH lights are the most common types of curing lights in an operatory. When you have either a QTH or an LED, light intensity decreases with the age of the light itself.15
The intensity of the LCU is also affected by many factors, including:16
 - Poor or reduced performance of the lamp or filter
 - Broken or dirty device tip
 - Blurred bulb
 - Electrical failure
 - Fiber defects
You might not know you have these problems with your curing light. You can't see when there's a fiber defect affecting the wavelength or if the lamp isn't "bright enough" to cure the material properly anymore. Feeling the composite after curing isn't going to work either; the surface can be hard even if the material deeper in the preparation suffers from inadequate curing.
Related reading: Covering a larger area in one cure
Regular maintenance will lower the risks of an inadequate cure resulting from a loss of intensity. In Canada, the CDSPI, a nonprofit organization dedicated to providing insurance and investment solutions, says curing light maintenance is essential to protect against malpractice claims.17
The Canadian Dental Association (CDA) also suggests testing the LCU output regularly and always ensuring that the LCU is in good working order before using it.18 The Journal of Clinical and Experimental Dentistry suggests using a digital radiometer to measure the intensity of the LCU, especially


text:
Lion's Pride Playground
Riverdale Ave. bet. Van Sinderen Ave. and Snediker Ave.
Directions via Google Maps
Lion's Pride Playground - House Sparrows in New York City Parks
If you look around Lion's Pride Playground, you will probably see house sparrows (Passer domesticus). This small, brown bird has a black bib (throat). Only 200 years ago, there were no house sparrows on the entire continent of North America. Today, it is estimated that there are over 150 million. The dramatic rise of the house sparrow in New York City and throughout North America can be attributed to 19th century industrialization and human manipulation of the environment.
There are conflicting rumors about why the sparrow was first brought to the United States. Some attribute its arrival to a group of well-read people who tried to introduce the birds mentioned in William Shakespeare's plays into the United States. Others believe that a single man imported the sparrow from England because he wanted to be reminded of home. Most people, however, agree that the house sparrow was brought to the United States because it was an attractive bird that could also control the growing insect populations of the time.
To accommodate the burgeoning human population of the city during the first half of the 19th century, much of the natural landscape was cleared away to make room for new housing and commercial developments. This extensive industrialization drove out many of New York City's native species, disturbing the natural balance of predator and prey. Insect infestations of trees and other plants became a major problem. Having heard that the house sparrows of European cities helped to control insect infestations, a group of New Yorkers imported eight pairs from England in 1850 and released them into the city. They survived for a time, but died before they were able to breed.
Soon afterward, Nicholas Pike, the director of the Brooklyn Institute, traveled to Liverpool, England to collect more sparrows. This time, 100 house sparrows were shipped back to the city. Half of them were released on arrival in 1851, while the other half were bred in Green-Wood Cemetery. These 50 birds were originally kept in the tower of the cemetery, but when they seemed unhappy, a leading citizen brought them to his house for the winter. The following year, these birds were released into the cemetery, where a man was employed just to take care of them.
This second wave succeeded where the first had failed. Due to the success of the introduction into Green-Wood Cemetery, several more shipments of sparrows arrived and were released in the cemetery and also Central Park, Union Square Park, and Madison Square Park. Other cities also imported sparrows from England or even from New York City, including Philadelphia, Salt Lake City, and San Francisco. While some considered the sparrows to be a loud nuisance, others were pleased that the birds were feeding on insects. In Boston, some citizens placed such a high value on their sparrows that a man was hired to shoot other birds that threatened them.
Lion's Pride Playground is named in honor of the lion (Panthera leo), an animal long celebrated as the King of the Beasts. In addition to its power and beauty, the lion is also famous for its fiercely close-knit social grouping, the pride. With each lion measuring about nine feet in length and weighing roughly 500 pounds, a pride has incredible strength. House sparrows, although smaller in size, can also have a great influence when traveling in their large flocks. While one can easily imagine the harmful effects of introducing hundreds of lions into New York City, smaller and seemingly less threatening species can also have a large impact on life in the city.
The house sparrow population grew so large because it was one of the first species to successfully populate urban areas. If there had been other dominant urban bird species, the house sparrow might not have survived. While the house sparrow population experienced a surge in one century, it has suffered a more recent decline due to the technological advances of the 20th century. As automobiles replaced horses for transportation and steel replaced wood for construction, the house sparrow could no longer nest in its usual areas and could not feed on oats scattered by horses. As the house sparrow population decreased, other species' populations, such as the pigeon (Columbia livia), have grown. Despite declines in population, the house sparrow remains ubiquitous. Today, Parks discourages the feeding of birds or squirrels in playgrounds because the leftover food can attract rats.


t^{e}_{i})|t_{pub}(d))\) can be larger when the timestamp is closer to the time period \((t^{s}_{i},t^{e}_{i})\), and when the importance weight \(w(t^{s}_{i},t^{e}_{i})\) of this period is large.
Content-Based Temporal Score Calculation. Next, we compute another temporal score, \(S_{text}^{temp}(d)\), of a candidate document d based on the relation between temporal information embedded in d's content and the candidate periods of time scope T(Q). We compute \(S_{text}^{temp}(d)\) because some news articles, even the ones published long time ago after the events mentioned in questions, may retrospectively refer to these events, providing salient information on them, and can thus help to distinguish between similar events. For example, articles published near a certain US presidential election may also discuss previous elections for comparison or for other purposes. Such references are often in the form of temporal expressions that refer to particular points in the past.
Temporal expressions are detected and normalized by the combination of temporal tagger (we use SUTime [29]) and temporal signals4 (words that help to identify temporal relations, e.g. "before","after","during"). The normalized result of each temporal expression is mapped to the time interval with the "start" and "end" information. For example, temporal expression "between 1999 and 2002" is normalized to [('1999-01', '2002-12')]. Special cases like "until January 1992" are normalized as [('', '1992-01')], since the "start" temporal information can not be determined. Finally, we can obtain a list of time scopes of temporal expressions contained in a document d, denoted as \(T_{text}(d)=\{\tau _1, \tau _2,...,\tau _{m(d)}\}\) where m(d) is the total number of temporal expressions found in d.
As each time scope \(\tau _i\) has its "start" information, denoted as \(\tau _i^{s}\), and "end" information, \(\tau _i^{e}\), we create two lists \(T^{s}_{text}(d)\), \(T^{e}_{text}(d)\) containing all \(\tau _i^{s}\) and all \(\tau _i^{e}\), respectively. Next, we construct two probability density functions by using kernel density estimation (KDE) based on these two lists. KDE is a technique closely related to histograms, which has characteristics that allow it to asymptotically converge to any density function. The probabilities of \(t^{s}(Q)\) and \(t^{e}(Q)\) denoted as \(S_{text}^{temp\_b}(d)\), \(S_{text}^{temp\_e}(d)\), respectively, can be then estimated using the probability density functions.
$$\begin{aligned} S_{text}^{temp\_b}(d)=\hat{f}\left( t^{s}(Q);h \right) = \frac{1}{m(d)}\sum _{i=1}^{m(d)}K_{h}\left( {t^{s}(Q)-\tau _i^{s}}\right) \end{aligned}$$
where h is a bandwidth (equal to 4) and K is a Guassian Kernel defined by:
$$\begin{aligned} K_{h}\left( x \right) =\frac{1}{\sqrt{2\pi } \cdot h}exp\left( -\frac{x^{2}}{2 \cdot h} \right) \end{aligned}$$
\(S_{text}^{temp\_e}(d)\) is calculated in the same way but using \(\tau _i^{e}\) and \(t^{e}(Q)\), and \(S_{text}^{temp}(d)\) is:
$$\begin{aligned} S_{text}^{temp}(d)=\frac{1}{2} \cdot (S_{text}^{temp\_b}(d)+S_{text}^{temp\_e}(d)) \end{aligned}$$
Final Temporal Score Calculation & Document Ranking. After computing the two temporal scores, the final temporal score of d is given by:
$$\begin{aligned} S^{temp}(d)=\frac{1}{2} \cdot (S_{pub}^{{temp}'}(d)+S_{text}^{{temp}'}(d)) \end{aligned}$$
where \(S_{pub}^{{temp}'}(d)\) and \(S_{text}^{{temp}'}(d)\) are the normalized values computed by dividing by the corresponding maximum scores among all candidate documents.
Additionally, document relevance score \(S^{rel}(d)\) is used after normalization:
$$\begin{aligned} S^{rel}(d)=\frac{BM25(d)}{MAX\_BM25} \end{aligned}$$
Finally, we rerank documents by a linear combination of their relevance scores and temporal scores:
$$\begin{aligned} S(d)= (1-\alpha (Q)) \cdot S^{rel}(d)+\alpha (Q) \cdot S^{temp}(d) \end{aligned}$$
\(\alpha (Q)\) is an important parameter, which determines the proportion between document temporal score and its relevance score. For example, when \(\alpha (Q)\) equals to 0.0, the relevance of the temporal information is completely ignored. As different questions have different shapes of the distributions of their relevant documents, we propose to dynamically determine \(\alpha (Q)\) per each question. The idea is that when a question has many bursts, meaning that the event of the question is frequently mentioned at different times or many similar or related events occurred over time, then time should play lesser role. In this case we want to decrease \(\alpha (Q)\) value to pay more attention to document relevance. In contrast, when only few bursts are found, which means that the question has obvious temporal character, time should be considered more. \(\alpha (Q)\) is computed as follows:
$$\begin{aligned} \alpha (Q)=\left\{ \begin{array}{rcl} 0.0&{}&{} {when\ burst\_num=0}\\ ce^{-(1-\frac{1}{burst\_num})} &{}&{} {elsewhere} \end{array} \right. \end{aligned}$$
c is a constant set to 0.25. \(\alpha (Q)\) assumes small values when the number of bursts is high, while it is the highest for the case of a single burst. When the relevant document distribution of the question does not exhibit any bursts, which also means that the list of candidate periods of the question time scope (T(Q)) is empty, \(\alpha (Q)\) is set to 0 and the reranking is based on document relevance.
3.3 Document Reader Module
For this module, we utilize a commonly used MRC model called BiDAF [30] which achieves Exact Match score 68.0 and F1 score 77.5 on the SQuAD 1.1 dev set. We use BiDAF model to extract answers of the top N reranked documents and we select the most common answer as the final answer. Note that BiDAF could be replaced by other MRC models, for example, the models that combine with Bert [3]. We use BiDAF for easy comparison with DrQA, whose reader component's performance is similar although a little better than the one of BiDAF.
4 Experiments
4.1 Experimental Setting
Document Archive and Test Set. As we mentioned before, NYT archive [31] is used as the underlying document collection, and is indexed using Solr. The archive contains over 1.8 million articles published from January 1987 to June 2007 and is often used for Temporal Information Retrieval researches [15, 16].
To evaluate the performance of our approach, we first need a set of answerable questions. To the best of our knowledge, there was no previous proposal for answering questions on news archives or available question answering test sets designed for news archives. Thus we have to manually construct the test set making sure that the questions can be answered in NYT archive. We finally construct a test set of 200 questions5 for NYT archive, that are carefully selected from other existing datasets and history quiz websites, and that (a) fall into the time frame of NYT archive, (b) their answers could be found in NYT archive and (c) they do not contain any temporal expressions6. The second condition was verified by manually selecting correct keywords from the questions and checking whether at least one retrieved document can infer the correct answer. Table 2 shows the distribution of resources used for creating the test set while Table 1 gives few examples.
Table 2.
Resources used for constructing the test set
TempQuestions [13]
SQuAD 1.1 [4]
History quizzes from funtrivia\(^\mathrm{a}\)
Wikipedia pages
Table 3.
Performance of different models using EM and F1
Top 1
Top 5
Top 10
Top 15
DrQA-NYT [9]
DrQA-Wiki [9]
QA-NLM-U [21]
QA


Welcome to Shengbao Special Cotton Machine Technology Co., Ltd. official website!
Does Saxo teach you how to pack the packer?
Type：News | Updatetime：2021-03-26 10:33:23
After the baler is purchased, how is the baling done when the baling is carried out, and what is the specific baling process? As a professional automatic baler manufacturer, I will take everyone to understand the baler packaging process. The packing process of the packing machine is composed of four links: feeding, tightening, cutting, and pasting.
During the belt feeding process, the belt feeding wheel rotates counterclockwise, and the friction between the toothed belt wheel and the packing belt is used to make the packing belt advance along the packing belt path until the end of the packing belt hits the micro switch of the stopper, So that the packing tape is stopped, and it is in the position to be packed.
In the process of tightening the strap, the right paw rises to press the end of the strap, and the feeding wheel rotates clockwise. The friction force is also used to make the strap withdraw along the rail frame. At this time, the blades in the rail are retracting from the strap. Under the action of pulling force, it is released, so that the packing belt is continuously withdrawn until it is close to the surface of the package, and the tensioning arm swings downwards to completely tighten the packing belt.
The next step is the cutting and ironing process. The left jaw rises and presses the two layers of packing belts. The isolation table exits and the ironing head follows up. The two ends of the packing belt are heated. This is when the pressure block rises and cuts the packing belt.
Then there is the pasting process. The ironing head exits the actual position, and the pressure block continues to rise, and the two layers are pressed together with the heated packing tape to complete the packing action.
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If you want to learn English well, you have to practice speaking English! Use these sentences to help you start interesting conversations in English.
- Samuel Butler
This is one of the most famous sayings about love. Even if we feel pain when we lose our love, it is a good thing for us. I am not sure I agree with this! How about you?
- Franklin P. Jones
"Love makes the world go round" is a common saying. It means that everything, even the whole world, depends on love. This man disagrees. Maybe love is not so important. Still, without love, the "ride" in the "car of life", or the "train of life", has no meaning. Just how important is love, in your opinion?
- Kahlil Kibran
This is very poetic. In a conversation, you might say the first half only, and ask your friends if they agree. I wonder if this kind of love is really possible. We often say "This is MY girlfriend" or "This is MY wife". Is love enough by itself, or do we need to possess our love?
- Martin Luther King Jr.
Do you think it's truly possible to follow in Dr. King's footsteps? What can ordinary people do to "drive out hate"? Does it matter how we live our daily lives or should we wait until we're important people in society?
- Maxime de la Rochefoucauld
Do you think you have ever been TRULY in love? Why do people "fall in love"? Why do some people "fall out" of love? Are there different kinds of love? How can we find "true" love?
- Amelia E. Barr
Have you ever loved somebody who didn't love you in return? If so, what was it like? Have you ever been loved by somebody that you didn't love? If so, how did that feel to you?
"Love is a temporary insanity curable by marriage."
- Ambrose Bierce
What a shocking thing to say! Why do you think he said it? How is love "cured" by marriage? And if love is a disease, do we really want to be cured? How can we keep love alive even after marriage?
Back to Teacher Joe's Words of Wisdom
"I have music, I have rhythm, who could ask for anything more?"
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text: This book teaches adhesive and sealant formulation in two steps. Each section first describes the application and chemical basis of the type of adhesive or sealant concerned. This is followed by formulation advice and – if possible – an analysis of existing recipes. This analysis includes a calculation of the important characteristic values of the formulations. All calculations based on recipes and formulations are worked through step by step and should therefore be intelligible to beginners, too.


text:
A shoebox diorama represents a scene within the confines of a shoebox. When used as a book report, you can decorate and arrange figures and objects inside of the shoebox to illustrate a scene from the book. Think of the shoebox as a theater stage, and you are the director, prop-master and set designer.
Capture The Moment
When making a diorama for a book report, it is important you choose a significant scene from the book to display in your diorama. Ideally, you want people who see your project to know which book it is from without being told, or having to read the title. Furthermore, if you capture a moment of action in your scene, it will draw attention and prompt those unfamiliar with your book to ask about what happens next in that scene.
Draw It Out
Before you start crafting figures and pasting colored paper to this inside of your shoebox, take the time to make a drawing of what you plan to do. Figure out which objects will go near the front and back and so on, so you don't get to the building stage and realize you don't have enough room for the important parts of your scene. Consider your sketch a blueprint, which will let you try different ideas without having to waste materials and construction time.
Build from Back to Front
It is tempting to begin by placing objects and decorations in the foreground of your scene first, because that is what the audience sees first, and the foreground is usually where the action happens. However, it is much easier to paint -- or apply colored -- paper to the background first, followed by any background objects before placing any of the foreground objects or decorating the front of the box.
Use The Lid
The lid of the shoebox is an effective tool that can significantly enhance the presentation of your diorama. You can use it as a base to increase the area of the "ground." If it's a hinge-type lid that is connected to the box, you can stand the box on end and use the lid as additional foreground space beside the main box area. You can even use this type of lid to represent space underwater or underground: simply keep the lid attached and place the box near the edge of the table, allowing the lid to drape down in front.
- Dan Kitwood/Getty Images News/Getty Images


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Imperatively modifying store data
Data in Relay stores can be imperatively modified within updater functions.
When to use updaters
Complex client updates
You might provide an updater function if the changes to local data are more complex than what can be achieved by simply writing a network response to the store and cannot be handled by the declarative mutation directives.
Client schema extensions
In addition, since the network response necessarily will not include data for fields defined in client schema extensions, you may wish to use an updater to initialize data defined in client schema extensions.
Use of other APIs
Lastly, there are things you can only achieve using updaters, such as invalidating nodes, deleting nodes, finding all connections at a given field, etc.
If multiple optimistic responses modify a given store value
If two optimistic responses affect a given value, and the first optimistic response is rolled back, the second one will remain applied.
For example, if two optimistic responses each increase a story's like count by one, and the first optimistic response is rolled back, the second optimistic response remains applied. However, it is not recalculated, and the value of the like count will remain increased by two.
When not to use updaters
To trigger other side effects
You should use the onCompleted callback to trigger other side effects. onCompleted callbacks are guaranteed to be called once, but updaters and optimistic updaters can be called repeatedly.
The various types of updater functions
The useMutation and commitMutation APIs accept configuration objects which can include optimisticUpdater and updater fields. The requestSubscription and useSubscription APIs accept configuration objects which can include updater fields.
In addition, there is another API (commitLocalUpdate) which also accepts an updater function. It will be discussed in the Other APIs for modifying local data section.
Optimistic updaters vs updaters
Mutations can have both optimistic and regular updaters. Optimistic updaters are executed when a mutation is triggered. When that mutation completes or errors, the optimistic update is rolled back.
Regular updaters are executed when a mutation completes successfully.
Example
Let's construct an example in which an is_new_comment field (which is defined in a schema extension) is set to true on a newly created Feedback object in a mutation updater.
# Feedback.graphql
extend type Feedback {
is_new_comment: Boolean
}
// CreateFeedback.js
import type {Environment} from 'react-relay';
import type {
FeedbackCreateData,
CreateFeedbackMutation,
CreateFeedbackMutation$data,
} from 'CreateFeedbackMutation.graphql';
const {commitMutation, graphql} = require('react-relay');
const {ConnectionHandler} = require('relay-runtime');
function commitCreateFeedbackMutation(
environment: Environment,
input: FeedbackCreateData,
) {
return commitMutation<FeedbackCreateData>(environment, {
mutation: graphql'
mutation CreateFeedbackMutation($input: FeedbackCreateData!) {
feedback_create(input: $input) {
feedback {
id
# Step 1: in the mutation response, spread an updatable fragment (defined below).
# This updatable fragment will select the fields that we want to update on this
# particular feedback object.
...CreateFeedback_updatable_feedback
}
}
}
',
variables: {input},
// Step 2: define an updater
updater: (store: RecordSourceSelectorProxy, response: ?CreateCommentMutation$data) => {
// Step 3: Access and nullcheck the feedback object.
// Note that this could also have been achieved with the @required directive.
const feedbackRef = response?.feedback_create?.feedback;
if (feedbackRef == null) {
return;
}
// Step 3: call store.readUpdatableFragment_EXPERIMENTAL
const {updatableData} = store.readUpdatableFragment_EXPERIMENTAL(
// Step 4: Pass it a fragment literal, where the fragment contains the @updatable directive.
// This fragment selects the fields that you wish to update on the feedback object.
// In step 1, we spread this fragment in the query response.
graphql'
fragment CreateFeedback_updatable_feedback on Feedback @updatable {
is_new_comment
}
',
// Step 5: Pass the fragment reference.
feedbackRef
);
// Step 6: Mutate the updatableData object!
updatableData.is_new_comment = true;
},
});
}
module.exports = {commit: commitCreateFeedbackMutation};
Let's distill what's going on here.
 - The updater accepts two parameters: a RecordSourceSelectorProxy and an optional object that is the result of reading out the mutation response.
 - The type of this second argument is a nullable version of the $data type that is imported from the generated mutation file.
 - The second argument contains just the data selected directly by the mutation argument. In other words, it will not contain any fields selected solely by spread fragments.
 - This updater is executed after the mutation response has been written to the store.
 - In this example updater, we do three things:
 - First, we spread an updatable fragment in the mutation response.
 - Second, we read out the fields selected by this fragment by calling readUpdatableFragment_EXPERIMENTAL. This returns an updatable proxy object.
 - Third, we update fields on this updatable proxy.
 - Once this updater completes, the updates that have been recorded are written to the store, and all affected components are re-rendered.
Example 2: Updating data in response to user interactions
Let's consider the common case of updating store data in response to a user interaction. In a click handler, let's a toggle an is_selected field. This field is defined on Users in a client schema extension.
# User.graphql
extend type User {
is_selected: Boolean
}
// UserSelectToggle.react.js
import type {RecordSourceSelectorProxy} from 'react-relay';
import type {UserSelectToggle_viewer$key} from 'UserSelectToggle_viewer.graphql';
const {useRelayEnvironment, commitLocalUpdate} = require('react-relay');
function UserSelectToggle({ userId, viewerRef }: {
userId: string,
viewerRef: UserSelectToggle_viewer$key,
}) {
const viewer = useFragment(graphql'
fragment UserSelectToggle_viewer on Viewer {
user(user_id: $user_id) {
id
name
is_selected
...UserSelectToggle_updatable_user
}
}
', viewerRef);
const environment = useRelayEnvironment();
return <button
onClick={() => {
commitLocalUpdate(
environment,
(store: RecordSourceSelectorProxy) => {
const userRef = viewer.user;
if (userRef == null) {
return;
}
const {updatableData} = store.readUpdatableFragment_EXPERIMENTAL(
graphql'
fragment UserSelectToggle_updatable_user on User @updatable {
is_selected
}
',
userRef
);
updatableData.is_selected = !viewer?.user?.is_selected;
}
);
}}
>
{viewer?.user?.is_selected ? 'Deselect' : 'Select'} {viewer?.user?.name}
</button>
}
Let's distill what's going on here.
 - In a click handler, we call commitLocalUpdate, which accepts a Relay environment and an updater function. Unlike in the previous examples, this updater does not accept a second parameter because there is no associated network payload.
 - In this updater function, we access get an updatable proxy object by calling store.readUpdatableFragment_EXPERIMENTAL, and toggle the is_selected field.
 - Like the previous example in which we called readUpdatableFragment_EXPERIMENTAL, this can be rewritten to use the readUpdatableQuery_EXPERIMENTAL API.
note
This example can be rewritten using the environment.commitPayload API, albeit without type safety.
Alternative API: readUpdatableQuery_EXPERIMENTAL.
In the previous examples, we used an updatable fragment to access the record whose fields we want to update. This can also be possible to do with an updatable query.
If we know the path from the root (i.e. the object whose type is Query) to the record we wish to modify, we can use the readUpdatableQuery_EXPERIMENTAL API to achieve this.
For example, we could set the viewer's name field in response to an event as follows:
// NameUpdater.react.js
function NameUpdater({ queryRef


text: Lambertville is a City in Hunterdon County, New Jersey, United States. As of the United States 2000 Census, the city population was 3,868. Lambertville was originally incorporated as a town by an Act of the New Jersey Legislature on March 1, 1849, from portions of West Amwell Township. The area was reincorporated as a city on March 26, 1872. Lambertville is located on the Delaware River in the southwestern portion of Hunterdon County. During the 1700s, the City was named after various operators of ferries across the river to Pennsylvania, ultimately becoming known as Coryell's Ferry, after Emanuel Coryell who owned the Ferry. Coryell's Ferry was the western terminus of the New Jersey portion of the York Road (which is now known as U.S. Highway 202) connecting New York City and Philadelphia. The City was named Lambertville in 1814 when the post office was established, in honor of John Lambert, a local resident, who had served as United States Senator and Acting Governor of New Jersey.


text:
On behalf of the Congress Organizing Committee it is our great pleasure to invite you to the fifth edition of the EUROBIOTECH 2013 Congress. The subject of the congress is this time dedicated to broader issues of life sciences with a special focus on "white" and"green" biotechnology.
The crucial issue that will be discussed is the innovation in science and the problem of overcoming the barriers in transferring the scientific knowledge into practical applications.
Congress is co-organized by Agricultural University in Krakow, Jagiellonian University (Faculty of BBB, and Collegium Medicum), Polish Federation of Biotechnology, Biotechnology Committee of Polish Academy of Sciences, Małopolska Center of Biotechnology and Targi w Krakowie Ltd.
Leading scientists in their fields will be invited to give most updated lectures on respective topics. Apart from Polish participants, we expect scientists and students from other countries, especially from Central Europe. The accompanying exhibition will gather companies from different sectors of biotechnology, creating an opportunity to exchange ideas and to establish cooperation between business and science.
Biotechnology is the science of the future. Therefore, let's meet in Kraków – where tradition unites with modernity and where, in historic academic interiors, the most innovative scientific ideas are developed.


text:
The Colombia: The Nature of Culture program at the 2011 Smithsonian Folklife Festival invited visitors to journey through the rich bio-cultural diversity of Colombia and explore how Colombian cultural expressions are inextricably connected to their distinctive environments.
The program highlighted six ecosystems and the urban centers of Bogotá, Medellín, and Cali. One hundred Colombian artists participated. They sang, danced, juggled, prepared food, and told stories. They wove ruanas, baskets, hats, hammocks; crafted sculptures, pots, canoes. And they demonstrated a variety of occupational processes and the ways in which their practices supported environmental sustainability. The program offered audiences a window into the country's unique cultural traditions in order to learn more about the creativity and vitality of Colombia's diverse population.
An itinerary for the journey
The journey through the Festival site was designed to begin in the (1) Andean Highlands of the eastern mountain range. Descending into the valley of the Magdalena River and the central mountain range, we traveled through the (2) Coffee Triangle. Heading north to the (3) Momposino Depression, we arrived in the lowlands of the Magdalena River, the cradle of the country's Caribbean culture. After crossing a third mountain range, we entered the (4) Pacific Rainforest, predominantly inhabited by people of African descent. A long journey to the east through the (5) Southeastern Plains took us to the ranching cultural frontier. Finally, we entered into the (6) Amazonian tropical rainforest where we explored a richly bio-diverse region inhabited by diverse indigenous communities. In Bogota, Medellín, and Cali, we examined the confluence of the primarily rural ecosystems in a Metropolitan setting.
Curator Olivia Cadaval gives an overview of the Colombia: The Nature of Culture program. Video shot and edited by Charles Weber.
Click for a detailed map of each region


text:
- Classification of cultivators
- How to choose a suitable cultivator for the land?
- Examples of the creation of the cultivator with your hands
- Example # 1 – Cultivator "Smart kid"
- Example # 2 – "Tornado"
- Example 3 – Disc rotary cultivator
- Example No. 4 – a Cultivator of chainsaws
- Example No. 5 – Cultivator from the engine or grinder
Before the creation of the handwritten cultivator, you first need to familiarize yourself with the principle of, design and existing functions. Now we will try to understand all this and give some striking examples of self-made cultivators, which will surely inspire you to create this miracle of technology.
Classification of cultivators
Classification of cultivators is highly complex and diverse, give examples of the main subtypes of cultivators for winter.
- Seedbed (steam) – used for continuous surface treatment
- Tilled – they treat the soil, located between the rows of sowing
- Rasteniepitateley – for working the soil between the rows with fertilizer special minerals
- Universal – used for solid and inter-row tillage
The number of processed rows:
- Single row
The type of the working parts:
By way of attaching to the tractor:
Possible work angle:
- Cultivators, working when tilted up to 20 degrees
- Cultivators, that work with any tilt of the earth's surface
- Light – used to work on small areas
- Medium – used on clay soils
- Heavy – duty professional units, which have greater engine power and the ability to attach additional equipment
The purpose of the work:
- Amateur – budget option, which provides for simple aggregations, employees for short-term work
- Semi-professional – Amateur differ from long-life operation
- Professional – is the most valuable technique, which is equipped with a powerful engine and has high reliability, unlike their "colleagues"
How to choose a suitable cultivator for the land?
To get started is to understand the purpose of various cultivators.
Light cultivators are ideal for small land, which has many different areas (the garden, lawn, garden, flower garden, etc.).
The average cultivators are suitable for larger plots of land.
If you need to track only belong to you the earth, do not buy professional units, because. they are very expensive, and the whole set of features you won't use. Then why throw your money away? It will be enough to buy a semi-professional cultivator, which, of course, will last you one season!
Examples of the creation of the cultivator with your hands
In order, to create the cultivator with your hands, it takes very little time and the orientation already taken by someone self-made unit. Now we bring to your attention 5 striking examples cultivators, which was created by gardeners at home
Example # 1 – Cultivator "Smart kid"
The simplest option is a homemade cultivator is this option. All you need is a pipe (the optimum diameter 24 mm, length of the respective growth), wheel (no more 20 cm in diameter), wooden axle, which will all be fixed, as well as studs and nuts.
First, attach the pipe to the wooden sticks (axis), and further to this same axle fasten wheel with studs and nuts. As a result, the axle rests on the wheel (which are recommended to be cut from metal, thick 2-3 mm) and lifted to a certain height above the ground depending on the diameter of the wheels. Small cultivator completely assembled and ready to work. All just, quickly and easily!
Example # 2 – "Tornado"
Creating a homemade cultivator of the type "Tornado" is as easy and quick, as in example No. 1. We need the components of this: strip of springy steel (length -50 cm, width – 2 cm, thickness – 1,5 mm) and wooden handle.
All we need is to bend the tape into a loop, attach it to a wooden handle and sharpened the edges with a file. It is recommended to create a "tornado" in diameter, a little less, than the distance between the rows (it usually is 20 cm).
Example 3 – Disc rotary cultivator
This option of the cultivator, created by your own hands, considered more complex, but an order of magnitude more efficient than the previous. It is possible not only to cultivate the land, but to align it, harrow and break up large pieces of land. The image below shows you a General view of disk rotary cultivator, and build order now we will provide you with. As for the necessary details, conventionally indicated in figure, these include: 1 disc, 2 –axis, 3 – Bush, 4 – great clip, 5 –little loop, 6 stock, 7 tube, 8 – handle.
First weld convex disks (they serve as working bodies of the cultivator) to sleeves, which are placed on the axis. Next, fix the axial ends, and for that we'll need splints, which are fixed in a large clip. Then you need to cut the top of the large bracket hole and fasten it to the pipe with handles and a crossbar. To a small bracket welded to the stock, diameter 24 mm and a length of 25 cm, in which further screwed rod diameter 16 mm.
That would give the disks a spherical shape, need to work with a hammer – strong strikes kick the bowl in the center of the disc. Immediately it is worth noting, this work heavy and require considerable physical effort.
Example No. 4 – a Cultivator of chainsaws
That would not have to spend a lot of money for the purchase of power tillers, was circulated this example, which shows how easy it is to create a cultivator, working on the basis of the motor chainsaw. To create it need a little "make friends" with technology, and also to have or to acquire some important components, which we now talk. All we need is:
- Metal corner
- Fuel tank
- Wheel (preferably the rubber)
- Sprocket on intermediate shaft (41 tooth)
- Sprocket (approach from the moped)
So, to start with the metal area weld a frame for the cultivator in the form of a cube, size 32*32 cm. To the top of the lateral parts attach the engine, lower the fuel tank (it is recommended to weld the bracket 15*15 cm). Then install a support for the intermediate shaft (place the angled upper upright). Then the supports are attached to the longitudinal angles (this is to mount bearings suspension shaft).
The center of gravity created by the tillers will fall on the supporting surface of the wheels, what makes operating the cultivator more comfortable. To create the handles we will need metal pipe (what would the handle was hard, choose a tube diameter of 30mm).
Stars we need to create a gear ratio from the intermediate shaft to the chassis. Depending on unit and operating conditions it is necessary correctly to pick up this gear ratio.
And finally collect all the elements of the Assembly together and enjoy his work. By the way the advantage of a homemade cultivator is less demanding in relation to fuels and lubricants, what can be said about imported models.
As you can see, the creation of such a cultivator does require certain technical skills, so if your "horse" Humanities, to make this miracle of technology will itself be a good task.
Example No. 5 – Cultivator from the engine or grinder
Another slightly tricky option of creating a device for the cultivation of the earth, which will save you money on the purchase of imported relative.
The advantage of this unit that, that rapid movement of the screw will carry out the breaking of the earth into large pieces, and slow just soften the soil.
The main element of such a cultivator is a reducer. To it will need welded 2 the area (on different sides), which will serve as the mount for the handles and axles. Selection of wheels is very important: big wheels is not easy, a little will get stuck and fail, so try to choose medium wheel.
Then machined the shaft and using sledgehammers oblivaetsya attachment for cultivator. In the remainder of the sleeve houses the shaft and welded screw-grouser. It is recommended to install the handle Assembly motor switch, that will make working more comfortable.
The provided examples are only a small fraction of cultivators, create yourself, therefore, if you have the imagination and love for art, you can create a unique unit for plowing the land. Wish you luck and brilliant ideas for creating garden machinery with his own hands! Recommend, also an article on, how to choose tiller to give.


Piano Lesson, The
1 Nominations
The Piano Lesson poster
1930's Pittsburgh, a brother comes home to claim "my half of the piano", a family heirloom; but his sister is not wanting to part with it. This is a glimpse of the conditions for African-Americans as well as some of the attitudes and influences on their lives. But whether he is able to sell the piano so that he can get enough money to buy some property and "no longer have to work for someone else" involves the story (or lesson) that the piano has to show him.
Season 1
Golden Globe Awards
1996 Nominee
1996 Nominee
Best Actor - Television Motion Picture
Charles S. Dutton


Sequential Max-Min Bilevel Programming with Incomplete Information and Learning
Speaker
Abstract
We present a framework for a class of sequential decision-making problems in the context of max-min bilevel programming, a class of hierarchical optimization problems with applications in network interdiction, defense, vulnerability analysis, among others. At each period, the leader allocates resources to disrupt the performance of the follower (e.g., as in the defender-attacker, attacker-defender or interdiction problems), who in turn minimizes some cost function over a set of activities that depend on the leader's decision. While the follower has complete knowledge of his/her problem, the leader has only partial information, and needs to learn about the cost parameters, available resources, and the follower's activities from the feedback generated by the follower's actions. We propose a class of greedy and robust policies and show that these policies are weakly optimal, eventually match the oracle's actions, and provide a real-time certificate of optimality. In particular, we measure policy performance in terms of its time-stability, defined as the number of periods it takes for the leader to match the actions of an oracle with complete information. We also study a lower bound on any policy performance based on the notion of a semi-oracle. Our numerical experiments demonstrate that the proposed policies consistently outperform several other reasonable benchmarks, and perform fairly close to the semi-oracle.


text:
We have investigated local element distributions in a Dy-doped Nd2Fe14B hot-deformed magnet by atomic-column resolution chemical mapping using an X-ray energy-dispersive spectrometer (XEDS) attached to an aberration-corrected scanning transmission electron microscope (Cscorrected STEM). The positions of the Nd and Dy atomic columns were visualized in the XEDS maps. The substitution of Dy was limited to a surface layer 2-3 unit cells thick in the Nd2Fe14B grains, and the Dy atoms preferentially occupied the 4f-Nd sites of Nd2Fe14B. These results provide further insights into the principal mechanism governing the coercivity enhancement due to Dy doping.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)


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text:
Examples of analysis sections
An example from a law field report about a courtroom observation
Click here to see the description section of this law field report.
| The legal processes I observed in the district court hearing reflect to a certain extent Australian social values. Their purpose is to attempt to maintain an efficient court system and create justice before the law. Processes such as rules of evidence which ensure only the most applicable evidence is heard have been developed over many years, thus demonstrating an influence of past and future cases. Similarly, the doctrine of precedent ensures that similar cases have similar results. Procedural grounds for objections protect witnesses from harassment and potential confusion. Therefore, all of these legal processes create an environment in which changing social values will bring about complementary changes in court decisions.
||The meaning and theoretical significance of the observations described are explored
Footnote 1: adapted from Woodward-Kron, R., Thomson, E. & Meek, J. (2000) A text based guide to academic writing. CD-Rom. Dept. Of Modern Languages, University of Wollongong.
An example from an education field report about a classroom practicum experience
| As I help the students I am conscious of the scaffolding Vygotsky described taking place. I observed other people such as teachers and parents scaffolding with their children. It was, therefore, interesting to realise that I was doing the same as I walked around the classroom helping the children with their tasks. Scaffolding helps the children to reach their zone of proximal development which in turn helps them to achieve more complex tasks.
I have found my practical experience in the classroom has been full of examples supporting the theories of Piaget and Vygotsky and to a lesser extent Erikson. It is also good to see that these theories actually have real world application to child development.
|Exploring the significance of practical experience and observations from a theoretical perspective
Reflection about what the field experience has meant for theoretical understanding
This is the analysis section from a history field report about historical monuments.
Click here to see the description section of this history field report.
The Bulli Coal Mining Company had 331 employees: this represented approximately 20% of the population of Bulli. Given the small size of the Bulli community, the population was calculated at 1352 persons in the 1891 census (Mitchell & Sherington, 1984: 42), and its dependence on the Bulli Coal Mining Company, the impact of a disaster of this magnitude was enormous. Henry Parkes and his government realising the hardship being experienced by the community, particularly the bereaved families, gave "official support to a public fund and established a board to distribute the money after investigating the needs of those bereaved" (Mitchell & Sherington, 1984: 58).
The impact of the disaster is reflected in the structure of the monument. The monument was intended to last the test of time. Its shape, an obelisk, is unlike anything else in the area. This fact combined with the historical use of the obelisk, principally in ancient Egypt, suggests the memorial was considered important to the community. No reference is made on the monument, however, in regard to the date of the dedication or to who unveiled it which is significant given the government support of a disaster relief fund for the Bulli community in the wake of the disaster.
Analysis of the event the monument commemorates
Conclusion drawn about the structure and shape of the monument given
Footnote 2: adapted from Flello, J. unpublished manuscript.
An example from an education field report about a classroom practicum experience. (This example contains a mixture of description and analysis within a single paragraph. This is an alternative approach to having these two types of different writing in separate sections.)
| Both childcare centres encouraged the children to think critically and reflectively about themselves and the wider community; for example, I observed an incident at centre 2 (14/5), where the teacher helped the children with an equity of access issue in the playground. Several children wanted to play on the slide and gym equipment but one child continually walked up the slide disrupting the pattern of play. The group of children began to speak loudly and harshly to him and threatened to kick him. The teacher was able to facilitate a resolution to this problem by getting the children to examine what was happening and think of alternative actions. There were all, in effect, being empowered to deal with the injustice they were facing in the playground rather than resorting to physical violence or giving up and playing elsewhere, as some children were about to do.
||Topic sentence: a general theoretical conclusion is drawn
Conclusion illustrated by an example observed in the field
Description of the observed event
Theoretical perspective used to analyse the event
Footnote 3: adapted from McNabb, Learning Skills Centre, University of Melbourne.
Comments and questions should
be directed to _EMAIL_


[Let's Study: Fantasy AGE by Green Ronin] Part 3: Basic Rules
Posted: August 5, 2015 by pointyman2000 in Fantasy AGE, Let's Study, Roleplaying Games
Tags:,,
Now that we've gotten the character creation out of the way, we turn our focus today to the basic rules of the game.
Before we get to talking about how to roll for tests in the Fantasy AGE system, let's talk about dice first. Fantasy AGE relies exclusively on six-sided dice.
The normal ability test is a 3d6 + Ability roll. However, its important to remember that you need to roll two dice of the same color, and a third die of another color. This differently colored die is called the Stunt Die, and is used to generate Stunt Points, determine degrees of success, or break ties.
Whenever you make an ability and roll doubles, you generate Stunt Points equal to the face value of the Stunt Die. These are then spent on special maneuvers. These are often Combat Stunts, though Spell, Roleplaying and Exploration stunts exist too.
Difficulties for Fantasy AGE range from 7 (Routine) to 21 (Nigh Impossible) with most tests being 11 (Average) or Challenging (13).
On a successful roll, you can determine how well your character did by checking the Stunt Die. A result of 1 means you barely succeeded while a 6 is a flawless success.
Fantasy AGE sticks to the basics here, introducing the concept of "Action time" to get new RPG players into the idea of turn-based combat.
Initiative is handled in standard fashion, with Dexterity (Initiative) ability test. For ties, the Stunt Die value acts as a tie breaker. Doubles don't do anything here, so no Stunt Points are generated.
Initiative is resolved from the highest Initiative roll down to the lowest, with lesser NPCs acting in groups. Initiative is only rolled once and remains the same throughout the fight.
Actions in Fantasy AGE are divided into Major and Minor Actions. During a turn, a character may perform 1 Major and 1 Minor action, or 2 Minor Actions. These can be performed in any sequence.
Major actions include: All-Out Attack, Charge, Defend, Heal, Melee Attack, Ranged Attack and Run.
Healing consumes bandages and allows a character to make a TN 11 Intelligence (healing) test to recover Health equal to the Stunt Die + the healer's Intelligence. A character cannot benefit from another Heal action until additional damage is taken.
Minor actions are: Activate, Aim, Guard Up, Move, Prepare, Press the Attack, Ready, Stand Firm.
Guard up allows the player to add a +1 or +2 to the character's Defense until the end of the round. The trade off is that they suffer the same value as a penalty to all actions they make for the rest of the round as well.
Press the Attack allows you to pursue a target opponent if they choose to move away in their next turn.
Stand Firm allows the character to try and resist any and all effort to move them from where they stand.
In addition to Major and Minor Actions, two other actions are considered to be Variable, as they can be Major or Minor depending on circumstances. These are the Cast and Reload actions.
Now that we've gone over the basics of actions, Combat is the next section covered. Combat is pretty straightforward in Fantasy AGE, as it usually relies on Ability Tests with Accuracy or Fighting vs the target's Defense as the TN.
Damage is resolved by rolling the weapon's damage rating and adding the attacking character's Strength Ability. This value is reduced by the opponent's armor.
This is where the magic happens. During a successful attack roll, if the player rolls doubles, they generate a number of Stunt Points equal to the value of the Stunt Die.
The Stunt Points must be used right away, and a stunt can only be performed once per round with the exception of the Skirmish Stunt.
The Combat Stunt list is pretty extensive, with 15 different stunts to choose from, costing anywhere from 1 to 5 SP each to execute. The Stunts range from anything from free movement, to free reloads, bonus damage, bonuses to tests and inflicting status effects on your target.
The Combat section also takes some time to talk about special rules regarding special cases. Grenades are given a few minor rules, and a special Stunt to go with it. Mounted combat considerations are provided with some bonuses to fighting mounted against opponents on foot and Flight is given some attention in the form of special Minor and Major actions.
Healing in Fantasy AGE is pretty straightforward. The Heal action was discussed earlier, but there are other options for healing, such as taking a 5-minute rest after combat, where a character recovers 5 + Constitution + Level of Health.
Another option is getting some sleep, which recovers 10 + Constitution + Level.
Finally, there's magical healing from the Healing Arcana (which we'll tackle later on in the Magic section of the Let's Study series.)
I'm really liking how Fantasy AGE is written with new players in mind. The rules are clear, and easy to comprehend, and there are enough examples to guide a new player through it without raising too many questions.
The Stunts are an interesting implementation of special maneuvers found in other games, and each time someone rolls doubles becomes a highlight in every encounter as the character suddenly does something above and beyond the usual "I hit, you hit" exchange.
Next up, we'll take a look at the Chapter of Character Options, which deals with Ability Focuses and Talents.
The Fantasy AGE Basic Rulebook is available in PDF format from DriveThruRPG for only $15.99 or roughly Php 720.
This Let's Study series made possible by Patreon. If you'd like to help me secure more titles to cover in detail, please consider becoming a patron!
 1. th3muser says:
 Fantastic! am thinking of picking this one up sometime. Trying to find a fantasy system that is a little less book keeping heavy than WFRP3.
 2. Cecil says:
 What does it mean to roll doubles here? Any two dice or only the same colored dice?
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ACCESSIBLE EDUCATION: How to Create Accessible Crossword Puzzles
Crossword Puzzles
Since 1858, The American Printing House for the Blind has operated in Louisville, Kentucky as the world's largest nonprofit organization creating accessible learning experiences through educational, workplace, and independent living products and services for people who are blind and visually impaired.
APH has created a web-based app for digital accessible crossword puzzles. These puzzles are fully accessible and can be navigated and solved using a screen reader. There are existing puzzles with academic content for 5th – 12th grade covering topics such as Science, Social Studies, Literature, Math, The Arts, Us History and World History. There are currently over a 100 existing puzzles available.
Need to create accessible crossword puzzles? Here are some resources that can help.
1) APH Accessible Crossword Puzzle App Review
2) Crossword Puzzle User Guide
This User Guide offers information on how to create new puzzles. This is a fantastic opportunity for teachers to take those crossword puzzle worksheets and make them accessible! These digital crossword puzzles also teach and provide opportunities to strengthen tech skills and digital grid math skills.
3) Sample Accessible Crossword Puzzles
Section 508: 15 US federal guidelines covered by 59 accessibility checkpoints


text:
Building a better maintenance schedule starts with understanding your assets and your resources, and how you can effectively bring the two together. This article looks at two core principles of PM scheduling, fixed and floating schedules, to help you better organize preventive maintenance.
Table of contents
Many everyday activities can be considered maintenance, from brushing your teeth to washing dishes. Most of these tasks are so routine, you barely think about how often you do them. Teeth are brushed at the same time every day and the dishwasher is run when it's full.
The same ideas guide preventive maintenance scheduling. Tasks are scheduled at certain intervals because it's what's best for the asset. But "what's best" for assets can differ. Understanding the difference allows you to coordinate PMs more effectively, build an efficient maintenance schedule, reduce the risk of downtime, effectively manage backlog, and control costs.
What are fixed and floating PM schedules?
Fixed PM scheduling is when regular maintenance is scheduled at a certain time or usage interval based on the target start date of the previous work.
For example, maintenance may be set up for a truck every 1,000 miles. A work order is triggered every 1,000 miles, regardless of when maintenance was last completed. That means that even if the previous PM was late (let's say it was done at 1,400 miles), the next PM would still be triggered at 2,000 miles. Fixed PMs can also be time-based. If that same truck is scheduled for maintenance every 10 days, a work order is sent out on the tenth day, whether the last PM was done on time, five days late, or not at all.
Building a better maintenance schedule starts with understanding your assets, your resources, and how to effectively bring the two together.
Floating PM scheduling is when preventive maintenance is scheduled based on the completion of the previous PM, the past usage of an asset, and the condition of the asset.
For example, a motor needs to be inspected after every 100 hours of operation. This maintenance might take place in a week or a month, depending on the production schedule. The next round of maintenance also changes if the motor is used differently. Maybe the motor is inspected after 120 hours of operation because a PM is done late. In this situation, the next work order for this PM would be triggered at 220 hours under a floating maintenance schedule.
When to use fixed PM scheduling
Fixed preventive maintenance scheduling doesn't work for every asset, nor does it work in every situation. There are a few scenarios when a fixed PM schedule works best and helps a facility use its resources efficiently while reducing downtime.
Maximizing labour and parts
Fixed PMs can help spread out tasks evenly for organizations with a large number of PMs. This makes it easier to plan labour and resources. Predictable tasks mean that the right number of staff and inventory (not too much and not too little) can be planned for a shift, day or week well in advance.
Creating effective schedules
If your facility has PMs that require shorter intervals, like daily or weekly, a fixed schedule is the easiest path to an effective schedule. It ensures that these tasks are completed consistently and on time, which is especially important when they're done on heavily used, production-critical assets.
Effectively managing warranties
Equipment manufacturers often recommend using a fixed PM schedule and can revoke warranties if these recommended schedules aren't followed. While you shouldn't completely base your maintenance schedule on warranties, it can be a factor, which makes sticking to a fixed schedule a good idea.
Meeting compliance regulations
Fixed PMs are generally more useful when certain assets or facilities are the focus of regulatory compliance or audits. Because a fixed schedule shows a predictable pattern, it is often seen as reliable proof that a facility is meeting certain regulatory benchmarks and is consistently giving attention to the necessary assets.
When to use floating PM scheduling
A floating PM schedule can be a more complex way to plan preventive maintenance and requires certain circumstances to work successfully. Certain assets and situations call for floating PMs more than others.
Increasing schedule flexibility
A floating schedule offers more flexibility for organizations with PMs that are spread over a long period of time and when those PMs can be late with minimal risk of failure or safety hazards. This flexibility allows the maintenance team to push PMs in favour of emergencies that have a huge impact on production.
Assessing risk and prioritizing tasks
Floating PMs are great for low-priority, routine preventive maintenance tasks that need to be completed on a regular basis, but won't affect the reliability or safety of equipment. In this situation, floating PMs allow the maintenance team to assess risk and prioritize tasks that matter most without an obligation to keep up with a strict schedule.
Coordinating maintenance and production schedules
A common use of floating schedules is for assets that are in high demand for production or service, but have a high degree of reliability and will not negatively impact safety or uptime if maintenance is late. The flexibility allows in a floating schedule means that unnecessary downtime can be reduced and uptime can be maximized.
How to use maintenance metrics to improve PM schedules
Asset type, asset history, and organizational processes determine whether you choose fixed or floating PMs for a piece of equipment. The next step is to set the frequency of these tasks. Maintenance metrics provide data to help you make this decision and optimize your schedule.
Mean time between failures
Mean time between failures (MTBF) helps establish how reliable an asset is and gets you closer to figuring out how long you have before that asset fails. This information can be used to shift PMs around and maximize time and resources without gambling with the health of equipment.
For example, an asset's MTBF may be 150 hours, but a preventive maintenance work order is created for the asset every 100 hours. It's apparent that the asset can be inspected less often, say every 125 hours. Having this information allows you to use time, labour, parts, and costs where they're needed more.
Preventive maintenance compliance
Preventive maintenance compliance (PM compliance) measures how successful your team is at completing preventive maintenance tasks. Keeping track of PM compliance for critical assets is one way to ensure time is being spent on the most important jobs and that you're not spreading the maintenance team too thin.
Tasks are scheduled at certain intervals because it's what is best for the asset. But "what's best" for assets can differ. Understanding the difference allows you to coordinate PMs more effectively.
For example, your facility's PM compliance on a critical piece of equipment might be 60%, which is very low. There are many potential reasons why PM compliance is low, but the most likely cause is a jam-packed schedule and not enough technicians to complete every task. In this situation, you can consider placing more technicians on these shifts or moving non-essential PMs to another day.
Maintenance cost as a percentage of replacement asset value
Maintenance cost as a percentage of replacement value (MPRAV) is one way to calculate if the value of an asset is worth the number of maintenance resources being given to it. A culture of total productive maintenance and better maintenance processes can reduce MPRAV and have an indirect, but huge, impact on PM scheduling.
For example, one of your assets might break down a lot. You're spending more time (and money) on PMs to reduce the frequency of failure. This puts a strain on the maintenance schedule. Calculating MPRAV helps you visualize these inefficiencies and find alternatives, like investing in new equipment, higher-quality parts, and better training. This leads to fewer breakdowns and less frequent PMs, leaving more time and money for other assets and PMs.
The bottom line on preventive maintenance scheduling
Every facility has unique assets, production schedules, and maintenance teams. That's why every facility will schedule its PMs a little differently. However, there are some tried and true methods for structuring and optimizing a PM schedule. This includes using fixed and floating schedules and metrics to bolster PM scheduling. When maintenance operations can apply these concepts to their schedule, it empowers them to cut costs, eliminate inefficiencies, use labour more effectively, and increase uptime.