Questões de Concurso
Comentadas sobre vocabulário | vocabulary em inglês
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The Naval Nuclear Propulsion Program (NNPP) started in 1948. Since that time, the NNPP has provided safe and effective propulsion systems to power submarines, surface combatants, and aircraft carriers. Today, nuclear propulsion enables virtually undetectable US Navy submarines, including the sea-based leg of the strategic triad, and provides essentially inexhaustible propulsion power independent of forward logistical support to both our submarines and aircraft carriers. Over forty percent of the Navy's major combatant ships are nuclear-powered, and because of their demonstrated safety and reliability, these ships have access to seaports throughout the world. The NNPP has consistently sought the best way to affordably meet Navy requirements by evaluating, developing, and delivering a variety of reactor types, fuel systems, and structural materials. The Program has investigated many different fuel systems and reactor design features, and has designed, built, and operated over thirty different reactor designs in over twenty plant types to employ the most promising of these developments in practical applications. Improvements in naval reactor design have allowed increased power and energy to keep pace with the operational requirements of the modern nuclear fleet, while maintaining a conservative design approach that ensures reliability and safety to the crew, the public, and the environment. As just one example of the progress that has been made, the earliest reactor core designs in the NAUTILUS required refueling after about two years while modern reactor cores can last the life of a submarine, or over thirty years without refueling. These improvements have been the result of prudent, conservative engineering, backed by analysis, testing, and prototyping. The NNPP was also a pioneer in developing basic technologies and transferring technology to the civilian nuclear electric power industry. For example, the Program demonstrated the feasibility of commercial nuclear power generation in this country by designing, constructing and operating the Shipping port Atomic Power Station in Pennsylvania and showing the feasibility of a thorium-based breeder reactor.
In: Report on Low Enriched Uranium for Naval Reactor Cores. Page 1. Report to Congress, January 2014. Office of Naval Reactors. US Dept. of Energy. DC 2058 http://fissilematerials.org/library/doe14.pdf
“[…] because of their demonstrated safety and reliability, these ships have access to seaports throughout the world.”
Choose the alternative that presents the words that would better translate, respectively, the ones in bold and underlined.
NASA Researchers Studying Advanced Nuclear Rocket Technologies
January 9, 2013
By using an innovative test facility at NASA’s Marshall Space Flight Center in Huntsville, Ala., researchers are able to use non-nuclear materials to simulate nuclear thermal rocket fuels - ones capable of propelling bold new exploration missions to the Red Planet and beyond. The Nuclear Cryogenic Propulsion Stage team is tackling a three-year project to demonstrate the viability of nuclear propulsion system technologies. A nuclear rocket engine uses a nuclear reactor to heat hydrogen to very high temperatures, which expands through a nozzle to generate thrust. Nuclear rocket engines generate higher thrust and are more than twice as efficient as conventional chemical rocket engines.
The team recently used Marshall’s Nuclear Thermal Rocket Element Environmental Simulator, or NTREES, to perform realistic, non-nuclear testing of various materials for nuclear thermal rocket fuel elements. In an actual reactor, the fuel elements would contain uranium, but no radioactive materials are used during the NTREES tests. Among the fuel options are a graphite composite and a “cermet” composite - a blend of ceramics and metals. Both materials were investigated in previous NASA and U.S. Department of Energy research efforts.
Nuclear-powered rocket concepts are not new; the United States conducted studies and significant ground testing from 1955 to 1973 to determine the viability of nuclear propulsion systems, but ceased testing when plans for a crewed Mars mission were deferred.
The NTREES facility is designed to test fuel elements and materials in hot flowing hydrogen, reaching pressures up to 1,000 pounds per square inch and temperatures of nearly 5,000 degrees Fahrenheit - conditions that simulate space-based nuclear propulsion systems to provide baseline data critical to the research team.
“This is vital testing, helping us reduce risks and costs associated with advanced propulsion technologies and ensuring excellent performance and results as we progress toward further system development and testing,” said Mike Houts, project manager for nuclear systems at Marshall.
A first-generation nuclear cryogenic propulsion system could propel human explorers to Mars more efficiently than conventional spacecraft, reducing crews’ exposure to harmful space radiation and other effects of long-term space missions. It could also transport heavy cargo and science payloads. Further development and use of a first-generation nuclear system could also provide the foundation for developing extremely advanced propulsion technologies and systems in the future - ones that could take human crews even farther into the solar system.
Building on previous, successful research and using the NTREES facility, NASA can safely and thoroughly test simulated nuclear fuel elements of various sizes, providing important test data to support the design of a future Nuclear Cryogenic Propulsion Stage. A nuclear cryogenic upper stage - its liquid- hydrogen propellant chilled to super-cold temperatures for launch - would be designed to be safe during all mission phases and would not be started until the spacecraft had reached a safe orbit and was ready to begin its journey to a distant destination. Prior to startup in a safe orbit, the nuclear system would be cold, with no fission products generated from nuclear operations, and with radiation below significant levels.
“The information we gain using this test facility will permit engineers to design rugged, efficient fuel elements and nuclear propulsion systems,” said NASA researcher Bill Emrich, who manages the NTREES facility at Marshall. “It’s our hope that it will enable us to develop a reliable, cost-effective nuclear rocket engine in the not-too-distant future."
The Nuclear Cryogenic Propulsion Stage project is part of the Advanced Exploration Systems program, which is managed by NASA’s Human Exploration and Operations Mission Directorate and includes participation by the U.S. Department of Energy. The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.
Marshall researchers are partnering on the project with NASA’s Glenn Research Center in Cleveland, Ohio; NASA’s Johnson Space Center in Houston; Idaho National Laboratory in Idaho Falls; Los Alamos National Laboratory in Los Alamos, N.M.; and Oak Ridge National Laboratory in Oak Ridge, Tenn.
The Marshall Center leads development of the Space Launch System for NASA. The Science & Technology Office at Marshall strives to apply advanced concepts and capabilities to the research, development and management of a broad spectrum of NASA programs, projects and activities that fall at the very intersection of science and exploration, where every discovery and achievement furthers scientific knowledge and understanding, and supports the agency’s ambitious mission to expand humanity’s reach across the solar system. The NTREES test facility is just one of numerous cutting-edge space propulsion and science research facilities housed in the state-of- the-art Propulsion Research & Development Laboratory at Marshall, contributing to development of the Space Launch System and a variety of other NASA programs and missions.
Available in: http://www.nasa.gov
“The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.”
Choose the alternative that presents the words that best substitutes, respectively, the bold and underlined ones in the sentences above
Is gas and oil drilling mostly computerized?
How much do you know about gas and oil drilling?
From locating new reserves to analyzing crude as it's refined, the oil and gas industry utilizes computer technology at every step of the way. Indeed, as proven reserves have dried up and new sources of oil and gas have become harder to find and exploit, computers have taken an increasingly important role in the industry.
That said, humans continue to be an essential part of the process. Though data may be collected and analyzed by a computer, it is a human, ultimately, that interprets the results and makes a decision to drill or move on. Though computers control the speed, force, and depth of a drill, it is a human that monitors and modifies the variables. And, of course, it is a human that makes the dangerous connections between drill pipes as the well pushes deeper.
Indeed, though computers have made drilling for oil and gas a safer and more efficient process, it remains a handson industry.
(adaptedfrom http://science.howstuffworks.com/environmental/energy/gas-oildrilling-computerized.htm)
Read text III and answer questions 60 to 70:
Text III
The use of music and songs in the EFL classroom
There are quite a lot of positive sides of learning English via
the medium music. First of all it is a very positive way of
learning English. Music is a part of our everyday life and
especially young people are very familiar with music. If the
5 teacher provides the possibility of a positive access to a new
topic, the kids will learn the new things easier and with more
fun and readiness. I am sure that the one or the other pupil
turns out to be a little “music-expert”. This can strengthen the
self-consciousness of students who are not so good at other
10 areas because now they have the opportunity to show what
they know about a special artist or band. Another pro of
teaching language by using songs and music is that it is
something different for the students – it is an alternation to
the common methods of language learning, because it is not
15 only interested in input. Learning with music speaks more than
other language-learning-methods to the audio-channel of the
learner, which has the positive effect of training listening and
comprehending language which is modified in terms of
intonation, pronunciation and articulation. Music in the
20 classroom can also be arranged in corporation with teachers of
other subjects, so that kids have the opportunity to use and
practise the new knowledge in more than one subject.
Teachers of English could not only work together with teachers
of music, but also with teachers of German, religion, ethics and
25 history. There is a variety of different thematic blocks which
can be taught with the help of songs, for example cultural or
social studies, to name only two areas.
However, using music and songs as a method of language
teaching can also have negative effects. Not every student likes
30 singing, acting or working with music and songs. Some find it
embarrassing and childish, especially older students. If the
majority of a class consists of students who feel like that about
working with music and songs in the classroom, the teacher
should be aware of the problem that it will be hard to motivate
35 the pupils. It can also be that some pupils protest and even
refuse to do several activities given by the teacher. […] Another
problem for teachers is the question of the right choice of
songs. Nowadays the kids are crazy about music which is called
“Death Metal”, “Hip Hop” or “Acid House”. So, many teachers
40 think that it is hard to fill the pupils of today with enthusiasm
by using Oldies.
Despite the fact that there are more positive effects of
learning a second language with songs and music than negative
ones, most teachers look at this method with mixed emotions.
45 Some are of the opinion that this is no real teaching and a
waste of time with some senseless activities. This is not true, of
course. Out of my own pupil-experience I can say that I have
learned quite a lot with the help of songs. I have acquired not
only a plenty of new words and vocabulary, but also several
50 idioms and many ways to express feelings.
(From http://www.grin.com/en/e-book/122444/the-use-of-music-and-songs-in-theefl-classroom)
In “Despite the fact that there are more positive effects” (line 42), the underlined phrase can be replaced without change in meaning by
Since the 1950’s, some athletes have been taking anabolic steroids to build muscle boost their athletic performance. Increasingly, other segments of the population also have been taking these compounds. An anual survey of drug abuse among adolescents showed a significant increase from 1998 to 1999 in steroid abuse among middle school students. During the same year, the percentage of 12th-graders who believed that taking these drugs causes “great risk” to health, declined from 68 percent to 62 percent.
Studies show that, over time, anabolic steroids can indeed take a heavy toll on a person’s health. The abuse of oral or injectable steroids is associated with higher risks for heart attacks and strokes, and the abuse of most oral steroids is associated with increased risk for liver problems. Steroid abusers who share needles or use non-sterile techniques when they inject steroids are at risk os contracting dangerous infections, such as HIV/AIDS, hepatites B and C, and bacterial endocarditis.
Anabolic steroid abuse can also cause undesirable body changes. These include breast development and genital shrinking in men, masculinization of the body in women, and acne and hair loss in both sexes.
[...] We hope that this compilation of scientific information on anabolic steroids will help the public recognize the risks of steroid abuse.
Alan I. Leshner, Ph.D. Director National Institute on Drug Abuse www.nida.nih.gov
Check the meaning of the word in bold.
- The abuse of steroids is associated with risks for heart attacks and strokes.
Leia o texto para responder à questão.
The Research Assignment
Students today have access to so much information that they need to weigh the reliability of sources. Any resource – print, human, or electronic – used to support your research inquiry has to be evaluated for its credibility and reliability. In other words, you have to exercise some quality control over what you use. When you use the print and multimedia materials found in your college library, your evaluation task is not so complicated because librarians have already established the credibility and appropriateness of those materials for academic research. The marketplace forces publishers to be discriminating as well.
Data collected in interviews of persons whose reliability is not always clearly established should be carefully screened, especially if you present this material as expert opinion or as based on knowledge of your topic. And you may have even more difficulty establishing trustworthiness for electronic sources, especially Web and Internet sources.
Because the Internet and World Wide Web are easy to use and accessible, Web material is volatile – it changes, becomes outdated, or is deleted. Its lack of consistency and sometimes crude form make Web information suspect for people who use it for research. Because there is frequently no quality control over Web information, you must critically evaluate all the material you find there, text and graphics alike.
(http://www.umuc.edu/writingcenter/onlineguide/
chapter4-07.cfm-27.10.2013. Adaptado)
Everyone keeps data. Big organizations spend millions to look after their payroll, customer and transaction data. The penalties for getting it wrong are severe: businesses may collapse, shareholders and customers lose money, and for many organizations (airlines, health boards, energy companies), it is not exaggerating to say that even personal safety may be put at risk. And then there are the lawsuits. The problems in successfully designing, installing, and maintaining such large databases are the subject of numerous books on data management and software engineering. However, many small databases are used within large organizations and also for small businesses, clubs, and private concerns. When these go wrong, it doesn't make the front page of the papers; but the costs, often hidden, can be just as serious.
Where do we find these smaller electronic databases? Sports clubs will have membership information and match results; small businesses might maintain their own customer data. Within large organizations, there will also be a number of small projects to maintain data information that isn't easily or conveniently managed by the large system-wide databases. Researchers may keep their own experiment and survey results; groups will want to manage their own rosters or keep track of equipment; departments may keep their own detailed accounts and submit just a summary to the organization's financial software.
Most of these small databases are set up by end users. These are people whose main job is something other than that of a Computer professional. They will typically be scientists, administrators, technicians, accountants, or teachers, and many will have only modest skills when it comes to spreadsheet or database software.
The resulting databases often do not live up to expectations. Time and energy is expended to set up a few tables in a database product such as Microsoft Access, or in setting up a spreadsheet in a product such as Excel. Even more time is spent collecting and keying in data. But invariably (often within a short time frame) there is a problem producing what seems to be a quite simple report or query. Often this is because the way the tables have been set up makes the required result very awkward, if not impossible, to achieve.
A database that does not fulfill expectations becomes a
costly exercise in more ways than one. We clearly have the
cost of the time and effort expended on setting up an
unsatisfactory application. However, a much more serious
problem is the unability to make the best use of valuable
data. This is especially so for research data. Scientific and
social researchers may spend considerable money and many
years designing experiments, hiring assistants and collecting
and analyzing data, but often very little thought goes into
storing it in an appropriately designed database.
Unfortunately, some quite simple mistakes in design can mean that much of the potential information is lost. The
immediate objective may be satisfied, but unforeseen uses
of the data may be seriously compromised. Next year's grant
opportunities are lost.
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