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[判断题]

DDN(Digital Data Network,数字数据网)传输可以一线多用。()

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更多“DDN(Digital Data Network,数字数据网)传输可以一线多用。()”相关的问题

第1题

For office innovators, the unrealized dream of the "paperless" office is a classic example
of high-tech hubris (傲慢). Today's office drone is drowning in more paper than ever before.

But after decades of hype, American offices may finally be losing their paper obsession. The demand for paper used to outstrip the growth of the US economy, but the past two or three years have seen a marked slowdown in sales—despite a healthy economic scene.

Analysts attribute the decline to such factors as advances in digital databases and communication systems. Escaping our craving for paper, however, will be anything but an easy affair.

"Old habits are hard to break," says Merilyn Dunn, a communications supplies director. "There are some functions that paper serves where a screen display doesn't work. Those functions are both its strength and its weakness. "

In the early to mid-90s, a booming economy and improved desktop printers helped boost paper sales by 6 to 7 percent each year. The convenience of desktop printing allowed office workers to indulge in printing anything and everything at very little effort or cost.

But now, the growth rate of paper sales in the United States is flattening by about half a percent each year. Between 2004 and 2005, Ms. Dunn says, plain white office paper will see less than a 4 percent growth rate, despite the strong overall economy. A primary reason for the change, says Dunn, is that for the first time ever, some 47 percent of the workforce entered the job market after computers had already been introduced to offices.

"We're finally seeing a reduction in the amount of paper being used per worker in the workplace," says John Maine, vice president of a pulp and paper economic consulting firm. "More information is being transmitted electronically, and more and more people are comfortable with the information residing only in electronic form. without printing multiple backups. "

In addition, Mr. Maine points to the lackluster employment market for white-collar workers—the primary driver of office paper consumption—for the shift in paper usage.

The real paradigm shift may be in the way paper is used. Since the advent of advanced and reliable office-network systems, data storage has moved away from paper archives. The secretarial art of "filing" is disappearing from job descriptions. Much of today's data may never leave its original digital format.

The changing attitudes toward paper have finally caught the attention of paper companies, says Richard Harper, a researcher at Microsoft. "All of a sudden, the paper industry has started thinking. 'We need to learn more about the behavioural aspects of paper use. '" he says. "They had never asked, they'd just assumed that 70 million sheets would be bought per year as a literal function of economic growth. "

To reduce paper use, some companies are working to combine digital and paper capabilities.

For example, Xerox Corp. is developing electronic paper: thin digital displays that respond to a stylus, like a pen on paper. Notations can be erased or saved digitally.

Another idea, intelligent paper, comes from Anoto Group. It would allow notations made with a stylus on a page printed with a special magnetic ink to simultaneously appear on a computer screen.

Even with such technological advances, the improved capabilities of digital storage continue to act against "paperlessness," argues Paul Saffo, a technology forecaster. In his prophetic and metaphorical 1989 essay, "The Electronic Pinata (彩罐)", he suggests that the increasing amounts of electronic data necessarily require more paper.

The information industry today is like a huge electronic pinata, composed of a thin paper crust surrounding an electronic core. " Mr. Saffo wrote. The growing paper crust "is most noticeab

A.It further explains high-tech hubris.

B.It confirms the effect of high-tech hubris.

C.It offers a cause for high-tech hubris.

D.It offers a contrast to high-tech hubris.

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第2题

Just how much does the Constitution protect your digital data? The Supreme Court will now
consider whether police can search the contents of a mobile phone without a warrant if the phone is on or around a person during an arrest.

California has asked the justices to refrain from a sweeping ruling particularly one that upsets the old assumption that authorities may search through the possessions of suspects at the time of their arrest. It is hard, the state argues, for judges to assess the implications of new and rapidly changing technologies. The court would be recklessly modest if it followed California’s advice. Enough of the implications are discernable, even obvious, so that the justices can and should provide updated guidelines to police, lawyers and defendants.

They should start by discarding California’s lame argument that exploring the contents of a smart phone — a vast storehouse of digital information — is similar to, say, rifling through a suspect’s purse. The court has ruled that police don’t violate the Fourth Amendment when they sift through the wallet or pocketbook of an arrestee without a warrant. But exploring one’s smart phone is more like entering his or her home. A smart phone may contain an arrestee’s reading history, financial history, medical history and comprehensive records of recent correspondence. The development of “cloud computing,” meanwhile, has made that exploration so much the easier.

Americans should take steps to protect their digital privacy. But keeping sensitive information on these devices is increasingly a requirement of normal life. Citizens still have a right to expect private documents to remain private and protected by the Constitution’s prohibition on unreasonable searches.

As so often is the case, stating that principle doesn’t ease the challenge of line-drawing. In many cases, it would not be overly onerous for authorities to obtain a warrant to search through phone contents. They could still invalidate Fourth Amendment protections when facing severe, urgent circumstances, and they could take reasonable measures to ensure that phone data are not erased or altered while a warrant is pending. The court, though, may want to allow room for police to cite situations where they are entitled to more freedom.

But the justices should not swallow California’s argument whole. New, disruptive technology sometimes demands novel applications of the Constitution’s protections. Orin Kerr, a law professor, compares the explosion and accessibility of digital information in the 21st century with the establishment of automobile use as a virtual necessity of life in the 20th: The justices had to specify novel rules for the new personal domain of the passenger car then; they must sort out how the Fourth Amendment applies to digital information now.

26. The Supreme Court will work out whether, during an arrest, it is legitimate to

A.prevent suspects from deleting their phone contents.

B.search for suspects’ mobile phones without a warrant.

C.check suspects’ phone contents without being authorized.

D.prohibit suspects from using their mobile phones.

The author’s attitude toward California’s argument is one ofA.disapproval

B.indifference

C.tolerance

D.cautiousness

The author believes that exploring one’s phone contents is comparable toA.principles are hard to be clearly expressed

B.the court is giving police less room for action

C.citizens’ privacy is not effectively protected

D.phones are used to store sensitive information

Orin Kerr’s comparison is quoted to indicate thatA.the Constitution should be implemented flexibly

B.new technology requires reinterpretation of the Constitution

C.California’s argument violates principles of the Constitution.

D.principles of the Constitution should never be altered

The author believes that exploring one’s phone contents is comparable toA.getting into one’s residence

B.handling one’s historical records

C.scanning one’s correspondences

D.going through one’s wallet

请帮忙给出每个问题的正确答案和分析,谢谢!

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第3题

Data sharing: an open mind on open date[ A] It is a movement building steady momentum: a c

Data sharing: an open mind on open date

[ A] It is a movement building steady momentum: a call to make research data, software code and experimental methods publicly available and transparent. a spirit of openness is gaining acceptance in the science community, and is the only way, say advocates, to address a&39;crisis&39; incience whereby too few findings are successfully reproduced. furthermore, they say, it is the best way for researchers to gather the range of observations that are necessary to speed up discoveries or to identify large-scale trends.

[B] the open-data shift poses a confusing problem for junior researchers. on the one hand,the drive to share is gathering official steam. since 2013, global scientific bodies have begun to back politics that support increased public access to reseach.on the other hand,scientists disagree about how much and when they should share date,and they debate whether sharing it is more likely to accelerate science and make it more robust, or to introduce vulnerabilities and problems.as more journals and make it more robust,or to introduce vulnerabilities and problems.as more journal and funders adopt data-sharing requirements, and as a growing number of enthusiasts call for more openness, junior researchers must find their place between adopters and those who continue to hold out, even as they strive to launch their own careers.

[C] one key challenge facing young scientists is how to be open without becoming scientifically vulnerable. they must determine the risk of jeopardizing a job offer or a collaboration prosal from those who are wary of-or unfamiliar with -open science. and they must learn How to capitalize on the movement&39;s benefits such as opportunities for more citations and a way to build a reputation without the need for conventional metrics, such as publication in high-impact journals.

[D] some fields have embraced open data more than others. researchers in psychology, a field rocked by findings of irreproducibility in the past few years, have been especially vocal sup-porters of the drive for more-open science.A few psychology journals have created incentives to increase interest in repar open science. a few psychology journals have created incentives porters of the drive for me lucible science -for example, by affixing an",badge to articles that clearly state where data are available. according to social psychologist brian nose executive director of the center for open science, the average data-sharing rate for the journal Psychological science, which uses the badges, increased tenfold to 38% from 2013 to 2015.

[E] funders, too, are increasingly adopting an open-data policy .several strongly ergement,and some require,a date-management plan that makes data available .The us national science foundation is among these, some philanthropic (慈善的) funders, including the bill Gates foundation in seattle, washington, and the wellcome trust in london, alopen data from their grant recipients.

[F] but many young researchers, especially those who have not been mentored in open science .are uncertain about whether to share or to stay private.Graduate students and postdoes,who often are working on their lab head&39;s grant may have no choice if their supervisor or another senior opposes sharing.

[G] some fear that the potential impact of sharing is too high, especially at the early stages of a career." Everybody has a scary story about someone getting scooped(被抢先),” says new York university astronomer david hogg. those fears may be a factor in a lingering hesitation to share data even when publishing in journals that mandate it.

[H] researchers at small labs or at institutions focused on teaching arguably have the most to lose when sharing hard-won data. ""with my institution and teaching load, i don&39;t have postdocs and grad students", says terry mcglynn, a tropical biologist at california state university,Dominguez hills. "the stakes are higher to share data because it&39;s a bigger fraction of hats happening in my lab.

[I] researchers also point to the time sink that is involved in preparing data for others to view.Once the data and associated materials appear in a repository(存储库 ), answering questions and handling complaints can take many hours.

[J] the time investment can present other problems. in some cases, says data scientist karthik Ram, it may be difficult for junior researchers to embrace openness when senior colleagues many of whom head selection and promotion teesht ridicule what they may view as misplaced energies. "i&39;ve heard this recently -that embracing the idea of open datad code makes traditional academics uncomfortable, "says ram. "the concem seems to be that open advocates don&39;t spend their time being as productive as possible."

[ K]an open-science stance can also add complexity to a collaboration. kate ratliff, who studies social attitudes at the university of florida, gainesville, says that it can seem as if there are two camps in a field-those who care about open science and those who don&39;t . " there a new area to navigate-&39;are you cool with the fact that i&39;ll want to make the data open?&39;-when talking with somebody about an interesting research idea, "she says.

[L] despite complications and concerns, the upsides of sharing can be significant. for example,when information is uploaded to a repository, a digital object identifier(DOI)is assigned.

Scientists can use a DOT to publish each step of the research life cycle, not just the final paper. In so doing, they can potentially get three citations- one each for the data and software.in addition to the paper itself. and although some say that citations for software or data have little currency in academia,they can have other benefits.

[M] many advocates think that transparent data procedures with a date and time stamp will protect scientists from being scooped. "this is the sweet spot between sharing and getting credit for it. while discouraging plagiarism(剽窃). " says ivo grigorov, a project coordinator at the naional institute of aquatic resot

Research secreta - in charlottenlund, denmark. hogg says that scooping is less of a problem than many think. "the two cases i&39;m familiar with didn&39;t involve open data or code, "he says.

[N] Open science also offers junior researchers the chance to level the palying field by gaining better access to crucial date. ross mounce, a postdoc studying evolutionary biology at the university of cambrige,UK, is a vocal champion of open science, partly because his fossil others&39; data. he says that more openness in science could help to discourage what some perceive as a commom practice of shutting out early-career scientists&39; requests for data.

[O] communication also helps for those who worry about jeopardizing a collaboration, he says,Concems about open should be discussed at the outset of a study. "whenever you start a project with someone, you have to establish a clear understanding of expectations for who owns the data, at what point they go public and who can do what with them, he says.

[p] in the end, sharing data, software and materials with colleagues can help an early -career researcher to gain recognition--a crucial component of success. "the thing you are searching for reputation" says titus brown,a genomics(基因组学) researcher at the university of Califomia, davis,."to get grants and jobs you have to be relevant and achieve some level of public recognition. anything you do that advances your presence- especially in a larger

phere, outside the communities you know- is a net win."

36. astronomer david hogg doesn&39;t think scooping is as serious a problem as generally thought.

37. some researchers are hesitant to make their data public for fear that others might publish something similar before them

38. some psychology joumals have offered incentives to encourage authors to share their data.

39. there is a growing demand in the science community that research data be open to the public.40. sharing data offers early-career researchers the chance to build a certain level of reputation

41. data sharing enables scientists to publish each step of their research work, thus leading to more citations

42. scientists hold different opinions about the extent and timing of data sharing

43. potential problems related to data sharing should be made known to and discussed by all participants at the beginning of a joint research project

44. sharing data and handling data-related issues can be time-consuming

45. junior researehers may have no say when it comes to sharing data.

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第4题

在新桥DDN终端设备DTu上,()灯表示DTu与DDN设备接通状态。

A.DTR

B.Line

C.Power

D.Ready

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第5题

DDN是()的传输网。

A.全透明

B.半透明

C.不透明

D.隐藏性

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第6题

一个DDN主要由哪几部分组成()。

A.本地传输系统

B.DDN结点

C.局间传输及网同步系统

D.网络管理系统

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第7题

接入Internet可通过()。

A.拨号上网

B.ISDN

C.DDN

D.卫星接入

E.ADSL

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第8题

DDN的构成包括那些部分?

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第9题

DDN专线的主要特点是安全、传输可靠性高。()
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