Daily News, military work environment.#Military #work #environment


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Big data, fast: Avoiding Hadoop performance bottlenecks #hadoop #environment #variables


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Big data, fast: Avoiding Hadoop performance bottlenecks

Hadoop shows a lot of promise as a relatively inexpensive landing place for the streams of big data coursing through organizations. The open source technology provides a distributed framework, built around highly scalable clusters of commodity servers, for processing, storing and managing data that fuels advanced analytics applications. But there’s no such thing as a free lunch: In production use, achieving high levels of Hadoop performance can be a challenge.

Despite all the attention it’s getting, Hadoop is still a relatively young technology — it only reached Version 1.0 status in December 2011. As a result, much of the work being done with Hadoop by users remains somewhat experimental in nature, especially outside of the large Internet companies that helped to create it and that are replete with Java programmers and systems administrators versed in deploying the technology.

In addition, the core combination of the Hadoop Distributed File System (HDFS) and MapReduce programming model has been joined by a continually expanding ecosystem of additional components. For example, there’s Flume, which speeds the collection and ingestion of log data into HDFS; Sqoop. a tool for moving data between Hadoop and structured databases; the Oozie job scheduler; and a multitude of other supporting technologies. In many big data systems, NoSQL databases of varying stripes — key-value stores, graph databases, document-oriented databases, others — are also in the mix.

Hadoop users ‘are dealing with an extremely deep protocol stack.’

Dominique Heger, CTO, DHTechnologies

Many of those added tools have potential performance ramifications for Hadoop systems ; piecing them together so they work well in tandem with one another can be a feat. System latency, memory settings, I/O bandwidth, job parallelization and Java Virtual Machine (JVM) settings are some of the other performance variables that IT and application development teams need to take into account. Otherwise, the best-laid data architecture plans could be stymied when companies try to put Hadoop into use .

Because of the effort it can take to build well-designed Hadoop clusters and applications that won’t bog down, there often are advantages to using commercial distributions of the software instead of the basic Apache Hadoop open source download, said Dmitriy Kalyada, a research and development engineer at software development services provider Altoros Systems Inc. in Sunnyvale, Calif. The commercial distributions also offer tools for more effectively monitoring the performance of the nodes in a cluster, he added.

Twists and turns on the Hadoop performance path

While adding more nodes is sometimes a straightforward path to improving Hadoop system performance, that isn’t always the case. Kalyada said you might expand a four-node Hadoop cluster to 20 nodes and not get a comparable five-fold increase in performance. In such cases, data architects and developers may have to go back to the drawing board and tweak their designs to get the desired throughput.

Getting data into and out of Hadoop at a quick clip can also be an issue because of its batch processing orientation, although the Hadoop community is actively brewing up solutions to the problem of batch latency. For example, several vendors have developed tools that support ad hoc analysis of Hadoop data through SQL queries or mainstream business intelligence tools. Also, a Hadoop 2.0 release that became available for beta testing in August makes MapReduce an optional component and lets users run other kinds of workloads, including real- or near-real-time processing jobs.

Meanwhile, some organizations are using complex event-processing engines to goose their Hadoop performance. Even Yahoo Inc. the company where Hadoop was first hatched, ran into problems with the technology, which had trouble keeping up with incoming information about the activities of online users that Yahoo wanted to correlate with its inventory of available ads.

Yahoo collects data on billions of such user events daily, according to Bruno Fernandez-Ruiz, a senior fellow and vice president for platforms at the company. But the data-collection process doesn’t stop to accommodate Hadoop. The problem with MapReduce computing is the batch window, he said. You have events coming in while running a batch job that is going to run two or three hours.

Knitting together a performance booster

In response, Yahoo implemented Storm-on-YARN. an application that pairs Hadoop 2.0’s new resource-management software with Storm, an open source complex event-processing tool. Fernando-Ruiz, who spoke at the Hadoop Summit 2013 in June, said that while MapReduce still handles long-running jobs, Storm processes low-latency events that can be added at the end of the batch run in order to provide a more complete view of website user activity.

For more on performance

Hadoop users are dealing with an extremely deep protocol stack, said Dominique Heger, owner and chief technology officer at DHTechnologies, an IT services company in Dripping Springs, Texas. And because the various tools communicate with one another through Java application programming interfaces, he continued, there are ample opportunities for Java coding practices to affect performance. You have to do a good study first to see how the Hadoop components will interact if you’re going to get the performance you’re looking for, Heger said.

Another way to enable good performance, Heger said, is to hew to the Hadoop mantra of moving computation to the data — i.e. distributing processing tasks to server nodes that are close to where the relevant data is stored in a cluster. But, he added, that’s the opposite of the approach most developers and database administrators are familiar with: moving data to an application for processing.

For many companies, there’s still a lot to learn about Hadoop — and a need to tread carefully. Hadoop and other big data technologies are a minefield for the uninitiated, said Kent Collins, a database engineer and architect at BNSF Railway Corp. in Fort Worth, Texas. But with time, experience and effective project management practices, the promise of fast Hadoop performance can come to pass.

This was last published in September 2013


Colorado Bureau Of Investigation Admits Dozens Of Faulty DUI Blood Tests –


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Colorado Bureau Of Investigation Admits Dozens Of Faulty DUI Blood Tests

DENVER (CBS4) Responding to a CBS4 investigation, the Colorado Bureau of Investigation has acknowledged at least 56 of the DUI blood tests it conducted in the last six months were incorrect.

“The initial results in each of those 56 cases showed lower alcohol levels for the drivers than when additional quality assurance retesting occurred, said Susan Medina, a spokesperson for the CBI. “There is no indication that any defendant was inappropriately charged with an offense based on test results showing an erroneously high level of alcohol in a driver’s bloodstream.”

The CBI opened labs in July 2015 in Pueblo and Grand Junction and since then has done about 1,500 DUI blood tests for the Colorado State Patrol and other law enforcement agencies. Medina said the faulty tests amounted to about 4 percent of the DUI testing the labs have conducted since last July.

The CBI said it learned of its erroneous lab results “in recent months“ when an independent lab checked two blood samples that had also been tested by the CBI and the independent lab ChemaTox discovered what the CBI calls “anomalies.

ChemaTox told CBS4 it notified state authorities of the problems in December 2015. The CBI said it then checked some of its other DUI alcohol results and confirmed its lab testing problems.

“While a thorough review remains in progress, said CBI, “it is believed the cause of the anomalies has been identified and corrected.

Medina declined to say if the problem was human error, testing equipment, or some other factor.

Sarah Urfer of ChemaTox labs told CBS4, “I contacted CBI and said, Look, we had an anomaly and it s 24 percent different.’

Urfer said the anomalies are important “because those are people’s lives at stake.

David Miller, a Denver-based defense attorney who defends DUI clients, told CBS4 the CBI needs to come clean.

“It creates a problem with the integrity of the system. They’re not saying what the problem is so we don’t know what the problem is, so we’re going to have to get full disclosure to start with. I think it s up to prosecutors now to look at each case and see if the convictions are proper in the first place and notify the client or lawyer as to what s happening, said Miller.

David Miller (credit: CBS)

He said the CBS4 investigation revealing the faulty testing shows a “huge problem. It’s a big deal if you’re the person affected by it. It’s a big deal individually and if you look at the big picture, if you are the person affected by this it’s a very big deal.

Miller said to re-establish credibility, the CBI needs to have all 1,500 blood samples it has examined since last July re-tested.

In many cases, blood drawn from a suspect is a critical piece of evidence establishing either guilt or innocence in DUI cases. There are an estimated 30,000 DUI cases in Colorado each year, according to the CBI.

Dr. Pat Sulik, a chemist with Rocky Mountain Instrumental Laboratories, checked 16 blood samples from the CBI in recent months. She said of those 16 samples, seven were problematic having at least a 5 percent variance from the readings she found. Of those seven, she said five had more than a 10 percent discrepancy.

Dr. Pat Sulik (credit: CBS)

Sulik said she would normally expect to have her results and the CBI results be nearly identical 99 percent of the time.

“To see this many discrepancies when the CBI just started this summer, this is, at a simple overview, way too many discrepancies, said Sulik. “When we saw our first large discrepancy we retested the sample and gave ourselves a heart attack.”

Sulik said the CBI’s erroneous, lower testing numbers mean “they are not being taken off the road, the DUI law is not being enforced if the state lab is coming up with lower numbers.

Sulik said in at least one case she checked, the suspect in a DUI case would have faced a more serious charge had the CBI lab testing been correct the first time around.

Ironically, the CBI only began doing this kind of testing after similar testing by the Colorado Department of Public Health and Environment came under fire in 2013 and CDPHE testing of DUI blood samples was shut down. In that case, defense attorneys maintained that the Department of Health testing was biased in favor of prosecutors and that staff was inadequately trained in handling blood samples.

In 2014 the state Legislature approved a bill providing nearly $2 million in annual funding and the hiring of five new full-time employees for the CBI to take over the DUI blood testing that was previously conducted by the Department of Health. Now the Department of Health is assisting in the investigation of the faulty CBI testing.

According to Medina’s statement to CBS4, ”After the review the CBI will issue amended reports to the law enforcement agencies that submitted the blood samples, and work with stakeholders to ensure accurate scientific results and prosecutions statewide.

Mike Rankin, the CBI Director, said, ”While the CBI works extremely hard to avoid any testing errors in our laboratories, the quality assurance procedures served their designed purpose of safeguarding the integrity of the program.

The CBI declined to answer any other questions from CBS4 citing an ongoing review of what happened. Medina said the agency might be able to provide more information once the review is completed.

Miller told CBS4 he intended to reopen any DUI cases he has handled in the last seven months that involved CBI blood testing. Urfer called the problem “very frustrating. I’ve been through this twice before. It seems like this should be a preventable problem. There are a number of labs that have not had these problems.


Polytech Montpellier #polytech, #polytech #montpellier, #polytechmontpellier, #ecole #d’ingenieur, #école #d’ingénieurs, #école #ingénieurs,


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Le rapport d’activité 2016 est disponible

NOUVELLE PLATEFORME RECRUTEMENT

Polytech en partenariat avec Job Teaser

Le réseau POLYTECH se dote d’une nouvelle plateforme de recrutement à destination de ses 15 000 élèves-ingénieurs. Les étudiants pourront y retrouver toutes les offres de stage ciblées qui correspondent à leur profil et à leurs critères de recherche.

Job Teaser permet d’accéder à des offres de stages, d’alternance, de VIE. Avec le filtre “Polytech”, des offres exclusivement réservées aux élèves ingénieurs Polytech s’affichent.

Conservez cette adresse. Cette adresse sera valable tout au long de votre vie professionnelle et vous permettra de maintenir un lien avec l’école.

Se connecter à Job Teaser

En cas de difficulté, contacter Jérémy Vacquié. responsable des Relations industrielles.

Table ronde sur la fabrication additive © N. Seling

5e soirée des partenaires

Sur le thème de la fabrication additive (3D)

Jeudi 29 juin a eu lieu la cinquième Soirée des partenaires de l’école, organisée par le service des Relations industrielles. L’événement a rassemblé environ quatre-vingt personnes, industriels, représentants du secteur économique régional, universitaires et étudiants.

Une table-ronde, animée par Fabien SOULIÉ, enseignant-chercheur, a abordé le thème de « La fabrication additive dans les applications industrielles, citoyennes, de la recherche et de la formation ».

Stéphane ABED, président de la société Poly shape, Yann LEFEBVRE, président du FabLab « LabSud », André CHRYSOCHOOS, directeur du centre PRO3D et Christian JORGENSEN, professeur au CHU de Montpellier et directeur de l’unité INSERM “Cellules souches, plasticité cellulaire, médecine régénératrice et immunothérapies”, sont intervenus pour partager leurs expériences et échanger sur les applications de ces technologies.

Les diverses interventions des invités ont permis de montrer le spectre très large des champs d’applications de ces nouvelles techniques de mise en œuvre de la matière, allant de l’industrie de pointe à la recherche médicale avancée, sans oublier les applications standardsaccessibles à tous ” précise Fabien Soulié.

Les présentations ont aussi su faire ressortir toutes les étapes de la démarche de conception, de dimensionnement et d’optimisation, préalables à la phase d’impressionproprement dite ” ajoute André Chrysochoos, concluant que “la fabrication additive est apparue aux participants comme une solution complémentaire aux techniques classiques de fabrication, mais possédant ses propres limites “.

Voir les photos de la soirée

A partir du 5 juillet 2017 à 14h

Votre inscription à POLYTECH Montpellier

Les i nscriptions seront ouvertes à partir du lundi 21 aôut 2017 à 14h et les réinscriptions jusqu’au mercredi 19 juillet 2017 et à partir du lundi 21 août 2017 à 14h.

Du 22 juillet au 20 août

Congés d’été

Attention, l’école ferme ses portes du samedi 22 juillet au 20 août. Réouverture prévue lundi 21 août. Bonnes vacances à tous !


Advanced Security Systems home burglar alarms and monitoring Northern VA #biometric #access


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We do not claim to be the largest national security company, as some of competitors boast, and we prefer it that way. We build our customer base one customer at a time. This is how we can offer you more personalized service. You will get to know our staff on a first name basis. We are not committed to any one monitoring station or manufacturer which allows us to custom design your personal security package that will protect you and your family with the best service and products available. And we do not use proprietary equipment nor do we put lock out codes in any of our panels. All products come with a minimum one year warranty on all parts and labor and in some instances the manufacturers have extended the warranty.

We also introduced three new product lines from Crestron, HAI and Powerhouse Dynamics for home automation and energy management. Like the rest of our many products these companies are some of the best in their respective industries.

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ADVANCED SECURITY SYSTEMS, Inc. sells and services Axis Communication. the leader in high-quality network cameras. Based on open IP standards, Axis network cameras connect to any kind of IP network, including the Internet, and enable remote viewing and recording from anywhere in the world. They also provide advanced video analytics features, such as motion detection, audio detection and tampering alarm.

Central Vac

Our company sales and services Beam Central Vacuum Systems for your cleaning and healthy home needs.
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ADVANCED SECURITY SYSTEMS, Inc. designs, installs and services CCTV systems that specifically meet your surveillance requirements. The CCTV systems are designed to provide video surveillance that you want of specific identified facility areas. Cameras and lenses are selected and placed to monitor those areas with camera activation per your requirements which could include constant monitoring or event monitoring activated by motion detectors or alarm devices. Recording is also designed based on your requirements using a DVR, with or without an internet connection, or tape recording using a VCR and a switcher or multiplexer.

Our professionals at ADVANCED SECURITY SYSTEMS, Inc. know the questions to ask and with their many years of experience know which components will best meet your needs.

ADVANCED SECURITY SYSTEMS, Inc. represents most of the major manufacturers of CCTV equipment available in the United States. Our CCTV technicians understand which manufacturer’s equipment works best in each particular situation. This knowledge base provides us with the ability to design a system that best meets your requirements in the most cost effective manner.

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ADVANCED SECURITY SYSTEMS, Inc. goal is to improve the lives of our customers using state-of-the-art technology designed for living, working, recreation and entertainment. Please call us today to enjoy the beauty and security of a truly interconnected home and lifestyle with integrated smart home, entertainment and communication systems. The great advantage of a home automation system is that you have the convenience of turning on/off and dimming lamps from your couch; beyond that you can save energy by turning off voltage sucking appliances and electronics that continue to draw power even when turned off.

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Radon (Rn) – Chemical properties, Health and Environmental effects #radon, #rn #chemical


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Radon – Rn

Radon is colorless at standard temperature and pressure and it is the most dense gas known. At temperature below it’s freezing point is has a brilliant yellow phosphorescence. It is chemically unreactive, it is highly radioactive and has a short half life.

Radon was sometimes used in hospitals to treat cancer and was produced as needed and delivered in sealed gold needles. Radon is used in hydrologic research, because of it’s rapid loss to air. It is also used in geologic research and to track air masses.

Radon in the environment

Radon can be found in some spring water and hot springs. There is anyway a detectable amount of radon in the atmosphere. Radon collects over samples of radium 226 at the rate of around 0.001 cm3/day per g of radium.

Radon occurs in the environment mainly in the gaseous phase. Consequently, people are mainly exposed to radon through breathing air.

Background levels of radon in outside air are generally quite low, but in indoor locations radon levels in air may be higher. In homes, schools and buildings radon levels are increased because radon enters the buildings through cracks in the foundations and basements.

Some of the deep wells that supply us with drinking water may also contain radon. As a result a number of people may be exposed to radon through drinking water, as well as through breathing air.

Radon levels in groundwater are fairly high, but usually radon is quickly released into air as soon as the groundwater enters surface waters.

Exposure to high levels of radon through breathing air is known to cause lung diseases. When long-term exposure occurs radon increases the chances of developing lung cancer. Radon can only cause cancer after several years of exposure.

Radon may be radioactive, but it gives of little actual gamma radiation. As a result, harmful effects from exposure to radon radiation without actual contact with radon compounds are not likely to occur.

It is not known whether radon can cause health effects in other organs besides the lungs. The effects of radon, which is found in food or drinking water, are unknown.

Radon is a radioactive compound, which rarely occurs naturally in the environment. Most of the radon compounds found in the environment derive from human activities. Radon enters the environment through the soil, through uranium and phosphate mines, and through coal combustion.

Some of the radon that is located in the soil will move to the surface and enter the air through vaporization. In the air, radon compounds will attach to dust and other particles. Radon can also move downwards in the soil and enter the groundwater. However, most of the radon will remain in the soil.

Radon has a radioactive half-life of about four days; this means that one-half of a given amount of radon will decay to other compounds, usually less harmful compounds, every four days.


The Energy Story – Chapter 3: Resistance and Static Electricity #renewable #energy


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Chapter 3: Resistance and Static Electricity

As we have learned, some kinds of atoms contain loosely attached electrons. Electrons can be made to move easily from one atom to another. When those electrons move among the atoms of matter, a current of electricity is created.

Take a piece of wire. The electrons are passed from atom to atom, creating an electrical current from one end to the other. Electrons are very, very small. A single copper penny contains more than 10,000,000,000,000,000,000,000 (1×1022) electrons.

Electricity “flows” or moves through some things better than others do. The measurement of how well something conducts electricity is called its resistance.

Resistance in wire depends on how thick and how long it is, and what it’s made of. The thickness of wire is called its gauge. The smaller the gauge, the bigger the wire. Some of the largest thicknesses of regular wire is gauge 1.

Different types of metal are used in making wire. You can have copper wire, aluminum wire, even steel wire. Each of these metals has a different resistance; how well the metal conducts electricity. The lower the resistance of a wire, the better it conducts electricity.

Copper is used in many wires because it has a lower resistance than many other metals. The wires in your walls, inside your lamps and elsewhere are usually copper.

A piece of metal can be made to act like a heater. When an electrical current occurs, the resistance causes friction and the friction causes heat. The higher the resistance, the hotter it can get. So, a coiled wire high in resistance, like the wire in a hair dryer, can be very hot.

Some things conduct electricity very poorly. These are called insulators. Rubber is a good insulator, and that’s why rubber is used to cover wires in an electric cord. Glass is another good insulator. If you look at the end of a power line, you’ll see that it is attached to some bumpy looking things. These are glass insulators. They keep the metal of the wires from touching the metal of the towers.

Another type of electrical energy is static electricity. Unlike current electricity that moves, static electricity stays in one place.

Try this experiment.

Rub a balloon filled with air on a wool sweater or on your hair. Then hold it up to a wall. The balloon will stay there by itself.

Tie strings to the ends of two balloons. Now rub the two balloons together, hold them by strings at the end and put them next to each other. They’ll move apart.

Rubbing the balloons gives them static electricity. When you rub the balloon it picks up extra electrons from the sweater or your hair and becomes slightly negatively charged.

The negative charges in the single balloon are attracted to the positive charges in the wall.

The two balloons hanging by strings both have negative charges. Negative charges always repel negative charges and positive always repels positive charges. So, the two balloons’ negative charges “push” each other apart.

Static electricity can also give you a shock. If you walk across a carpet, shuffling your feet and touching something made of metal, a spark can jump between you and the metal object. Shuffling your feet picks up additional electrons spread over your body. When you touch a metal doorknob or something with a positive charge the electricity jumps across the small gap from your fingers just before you touch the metal knob. If you walk across a carpet and touch a computer case, you can damage the computer.

One other type of static electricity is very spectacular. It’s the lightning in a thunder and lightning storm. Clouds become negatively charged as ice crystals inside the clouds rub up against each other. Meanwhile, on the ground, the positive charge increases. The clouds get so highly charged that the electrons jump from the ground to the cloud, or from one cloud to another cloud. This causes a huge spark of static electricity in the sky that we call lightning.

You can find out more about lightning at Web Weather for Kids – www.ucar.edu/40th/webweather/

You’ll remember from Chapter 2 that the word “electricity” came from the Greek words “elektor,” for “beaming sun” and “elektron,” both words describing amber. Amber is fossilized tree sap millions of years old and has hardened as hard as a stone.

Around 600 BCE (Before the Common Era) Greeks noticed a strange effect: When rubbing “elektron” against a piece of fur, the amber would start attracting particles of dust, feathers and straw. No one paid much attention to this “strange effect” until about 1600 when Dr. William Gilbert investigated the reactions of magnets and amber and discovered other objects can be made “electric.”

Gilbert said that amber acquired what he called “resinous electricity” when rubbed with fur. Glass, however, when rubbed with silk, acquired what he termed “vitreous electricity.”

He thought that electricity repelled the same kind and attracts the opposite kind of electricity. Gilbert and other scientists of that time thought that the friction actually created the electricity (their word for the electrical charge).

In 1747, Benjamin Franklin in America and William Watson in England both reached the same conclusion. They said all materials possess a single kind of electrical “fluid.” They didn’t really know anything about atoms and electrons, so they called how it behaved a “fluid.”

They thought that this fluid can penetrate matter freely and couldn’t be created or destroyed. The two men thought that the action of rubbing (like rubbing amber with fur) moves this unseen fluid from one thing to another, electrifying both.

Franklin defined the fluid as positive and the lack of fluid as negative. Therefore, according to Franklin, the direction of flow was from positive to negative. Today, we know that the opposite is true. Electricity flows from negative to positive. Others took the idea even further saying this that two fluids are involved. They said items with the same fluid attract each other. And opposite types of fluid in objects will make them repel each other.

All of this was only partially right. This is how scientific theories develop. Someone thinks of why something occurs and then proposes an explanation. It can take centuries sometime to find the real truth. Instead of electricity being a fluid, it is the movement of the charged particles between the objects. the two objects are really exchanging electrons.

Learn about Electrical Circuits and electrons in Chapter 4.


Ohio state insurance #ohio, #business #portal, #starting #a #business, #hiring, #training, #employees,


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Bureau of Workers’ Compensation monthly employer webinars

BWC is beginning a new series of brief, informative webinars on topics of interest to employers. Webinars will be offered twice a month and will be about 20-25 minutes. To kick things off, June webinars will cover policy year 2017 renewal, the 2-percent early pay discount and future dating of payments.

Ohio Materials Marketplace

The Ohio Materials Marketplace is a free online platform allowing businesses and organizations to connect and find reuse and recycling solutions for waste and by-product materials.

Ohio Business Central

File business documents online with Ohio Business Central. Available online forms include: articles of incorporation for domestic corporations, nonprofits, and professional associations; articles of organization for a domestic limited liability company; foreign for profit and nonprofit corporation application for license; foreign limited liability company registration; trade and fictitious name registration and renewal; and biennial reports for associations and limited liability partnerships, and more.

view all Gateway topics


Android App #mobile #app #development #environment


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Arizona Mobile

The University’s official mobile app

Where can you experience all things UA while on the go

Need to navigate campus, see class availability and location, or catch the next CatTran? Want to get UA sports updates, check your CatMail, or see how busy the Rec Center is with a simple touch? The Arizona Mobile app integrates the entire UA experience into a streamlined, live, and limitless interface.

FREE download for iPhone®, iPad®, Android®, and available as mobile web.

Mobile matters

Your source for mobile development for and about The University of Arizona.

Alumni

Any Question

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Bookstore

Campus Health

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CatMail

CatTran

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Phonebook

SafeRide

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UAccess