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151.
Philip Hunter 《Computer Fraud & Security》2004,2004(7):11-12
It was clearly bad news for Cisco itself when a portion of its IOS software surfaced for a few days in May on a Russian website. But it was difficult to obtain a consensus within the security industry over the potential threat posed by the breach to the Internet as a whole or to the countless private IP networks. Given that IOS drives most of the world's routers that direct traffic both through the Internet and private networks, theft of some of its source code clearly gives hackers the potential to exploit vulnerabilities that would be hard to identify otherwise. Naturally the Open Source community pounced on the issue, as they did earlier in the year when some Microsoft Windows source code was stolen, with the argument that any system relying on secrecy for security is fundamentally flawed and by definition insecure. Kerckhoff's law that “a system should be designed to be secure if everything is known about it except the key information” was trotted out as an argument that closed source software such as IOS and Windows would soon be extinct, ushering in the golden age of open source. 相似文献
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Anton Kurz Jürgen J. Schmied Kristin S. Grußmayer Phil Holzmeister Philip Tinnefeld Dirk‐Peter Herten 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(23):4061-4068
Obtaining quantitative information about molecular assemblies with high spatial and temporal resolution is a challenging task in fluorescence microscopy. Single‐molecule techniques build on the ability to count molecules one by one. Here, a method is presented that extends recent approaches to analyze the statistics of coincidently emitted photons to enable reliable counting of molecules in the range of 1–20. This method does not require photochemistry such as blinking or bleaching. DNA origami structures are labeled with up to 36 dye molecules as a new evaluation tool to characterize this counting by a photon statistics approach. Labeled DNA origami has a well‐defined labeling stoichiometry and ensures equal brightness for all dyes incorporated. Bias and precision of the estimating algorithm are determined, along with the minimal acquisition time required for robust estimation. Complexes containing up to 18 molecules can be investigated non‐invasively within 150 ms. The method might become a quantifying add‐on for confocal microscopes and could be especially powerful in combination with STED/RESOLFT‐type microscopy. 相似文献
154.
Philip N. James 《Information Systems Management》2013,30(2):52-53
Computers are transforming the workplace as users discover Innovative ways to put their power to work. To effectively manage their employees, managers must understand —and exploit — all facets of the user Interface. 相似文献
155.
This paper uses two large databases, one of given names and one of family names, to categorise the names of researchers from Italy, Sweden, the UK and the USA whose papers in astronomy and oncology were published in 2006–2007 and in 2011–2012 by sex (gender) and ethnicity or national origin. For all the countries, there were relatively many more females publishing papers in oncology than in astronomy, but their share of contributions was lower than the percentage of researchers. Sweden and the UK had much higher percentages of both other European and Rest of the World researchers than Italy did. US researchers with non-European names were categorised in six main country groups. The ones with the greatest presence were Chinese (mainly Mandarin) and South Asians (mainly Indians). The method could be adapted to investigate the progress of women in research in many other countries, and the role played by non-national researchers in their scientific output. 相似文献
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Philip J. Nickel 《Minds and Machines》2013,23(4):489-502
Some of the systems used in natural language generation (NLG), a branch of applied computational linguistics, have the capacity to create or assemble somewhat original messages adapted to new contexts. In this paper, taking Bernard Williams’ account of assertion by machines as a starting point, I argue that NLG systems meet the criteria for being speech actants to a substantial degree. They are capable of authoring original messages, and can even simulate illocutionary force and speaker meaning. Background intelligence embedded in their datasets enhances these speech capacities. Although there is an open question about who is ultimately responsible for their speech, if anybody, we can settle this question by using the notion of proxy speech, in which responsibility for artificial speech acts is assigned legally or conventionally to an entity separate from the speech actant. 相似文献
159.
Zoe R. Howard Corliss A. O'Bryan Philip G. Crandall Steven C. Ricke 《Food research international (Ottawa, Ont.)》2012,45(2):755-764
Foodborne illness caused by Salmonella spp. is a worldwide problem. In the United States Salmonella Enteritidis is the second most commonly isolated serotype from human illness, and is known to be strongly associated with shell eggs and egg containing products. Eggs can become contaminated internally either by penetration through the shell or directly during formation in the reproductive tract. This review begins with a brief account of the physiology of egg production and the various physical and chemical barriers the egg possesses to prevent bacterial contamination. Factors involved in vertical and horizontal transmission of S. Enteritidis are examined, as well as the role of forced molt in colonization of the hen. Pre- and post-harvest mitigation strategies are also discussed. 相似文献
160.