Search (6 results, page 1 of 1)

0.057619434 = product of:
  0.11523887 = sum of:
    0.11523887 = sum of:
      0.08078188 = weight(_text_:policy in 2753) [ClassicSimilarity], result of:
        0.08078188 = score(doc=2753,freq=2.0), product of:
          0.2727254 = queryWeight, product of:
            5.361833 = idf(docFreq=563, maxDocs=44218)
            0.05086421 = queryNorm
          0.29620224 = fieldWeight in 2753, product of:
            1.4142135 = tf(freq=2.0), with freq of:
              2.0 = termFreq=2.0
            5.361833 = idf(docFreq=563, maxDocs=44218)
            0.0390625 = fieldNorm(doc=2753)
      0.03445699 = weight(_text_:22 in 2753) [ClassicSimilarity], result of:
        0.03445699 = score(doc=2753,freq=2.0), product of:
          0.1781178 = queryWeight, product of:
            3.5018296 = idf(docFreq=3622, maxDocs=44218)
            0.05086421 = queryNorm
          0.19345059 = fieldWeight in 2753, product of:
            1.4142135 = tf(freq=2.0), with freq of:
              2.0 = termFreq=2.0
            3.5018296 = idf(docFreq=3622, maxDocs=44218)
            0.0390625 = fieldNorm(doc=2753)
  0.5 = coord(1/2)

Abstract

Social networks evolve over time with the addition and removal of nodes and links to survive and thrive in their environments. Previous studies have shown that the link-formation process in such networks is influenced by a set of facilitators. However, there have been few empirical evaluations to determine the important facilitators. In a research partnership with law enforcement agencies, we used dynamic social-network analysis methods to examine several plausible facilitators of co-offending relationships in a large-scale narcotics network consisting of individuals and vehicles. Multivariate Cox regression and a two-proportion z-test on cyclic and focal closures of the network showed that mutual acquaintance and vehicle affiliations were significant facilitators for the network under study. We also found that homophily with respect to age, race, and gender were not good predictors of future link formation in these networks. Moreover, we examined the social causes and policy implications for the significance and insignificance of various facilitators including common jails on future co-offending. These findings provide important insights into the link-formation processes and the resilience of social networks. In addition, they can be used to aid in the prediction of future links. The methods described can also help in understanding the driving forces behind the formation and evolution of social networks facilitated by mobile and Web technologies.

Date

22. 3.2009 18:50:30

0.014136827 = product of:
  0.028273653 = sum of:
    0.028273653 = product of:
      0.056547306 = sum of:
        0.056547306 = weight(_text_:policy in 3232) [ClassicSimilarity], result of:
          0.056547306 = score(doc=3232,freq=2.0), product of:
            0.2727254 = queryWeight, product of:
              5.361833 = idf(docFreq=563, maxDocs=44218)
              0.05086421 = queryNorm
            0.20734155 = fieldWeight in 3232, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              5.361833 = idf(docFreq=563, maxDocs=44218)
              0.02734375 = fieldNorm(doc=3232)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Abstract

Making the Nation Safer: The Role of Science and Technology in Countering Terrorism The commitment of the scientific, engineering, and health communities to helping the United States and the world respond to security challenges became evident after September 11, 2001. The U.S. National Research Council's report an "Making the Nation Safer: The Role of Science and Technology in Countering Terrorism," (National Research Council, 2002, p. 1) explains the context of such a new commitment: Terrorism is a serious threat to the Security of the United States and indeed the world. The vulnerability of societies to terrorist attacks results in part from the proliferation of chemical, biological, and nuclear weapons of mass destruction, but it also is a consequence of the highly efficient and interconnected systems that we rely an for key services such as transportation, information, energy, and health care. The efficient functioning of these systems reflects great technological achievements of the past century, but interconnectedness within and across systems also means that infrastructures are vulnerable to local disruptions, which could lead to widespread or catastrophic failures. As terrorists seek to exploit these vulnerabilities, it is fitting that we harness the nation's exceptional scientific and technological capabilities to Counter terrorist threats. A committee of 24 of the leading scientific, engineering, medical, and policy experts in the United States conducted the study described in the report. Eight panels were separately appointed and asked to provide input to the committee. The panels included: (a) biological sciences, (b) chemical issues, (c) nuclear and radiological issues, (d) information technology, (e) transportation, (f) energy facilities, Cities, and fixed infrastructure, (g) behavioral, social, and institutional issues, and (h) systems analysis and systems engineering. The focus of the committee's work was to make the nation safer from emerging terrorist threats that sought to inflict catastrophic damage an the nation's people, its infrastructure, or its economy. The committee considered nine areas, each of which is discussed in a separate chapter in the report: nuclear and radiological materials, human and agricultural health systems, toxic chemicals and explosive materials, information technology, energy systems, transportation systems, Cities and fixed infrastructure, the response of people to terrorism, and complex and interdependent systems. The chapter an information technology (IT) is particularly relevant to this special issue. The report recommends that "a strategic long-term research and development agenda should be established to address three primary counterterrorismrelated areas in IT: information and network security, the IT needs of emergency responders, and information fusion and management" (National Research Council, 2002, pp. 11 -12). The MD in information and network security should include approaches and architectures for prevention, identification, and containment of cyber-intrusions and recovery from them. The R&D to address IT needs of emergency responders should include ensuring interoperability, maintaining and expanding communications capability during an emergency, communicating with the public during an emergency, and providing support for decision makers. The R&D in information fusion and management for the intelligence, law enforcement, and emergency response communities should include data mining, data integration, language technologies, and processing of image and audio data. Much of the research reported in this special issue is related to information fusion and management for homeland security.

0.010337097 = product of:
  0.020674193 = sum of:
    0.020674193 = product of:
      0.041348387 = sum of:
        0.041348387 = weight(_text_:22 in 2733) [ClassicSimilarity], result of:
          0.041348387 = score(doc=2733,freq=2.0), product of:
            0.1781178 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.05086421 = queryNorm
            0.23214069 = fieldWeight in 2733, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=2733)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Date

22. 3.2009 17:57:50

0.008614248 = product of:
  0.017228495 = sum of:
    0.017228495 = product of:
      0.03445699 = sum of:
        0.03445699 = weight(_text_:22 in 7469) [ClassicSimilarity], result of:
          0.03445699 = score(doc=7469,freq=2.0), product of:
            0.1781178 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.05086421 = queryNorm
            0.19345059 = fieldWeight in 7469, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0390625 = fieldNorm(doc=7469)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Source

IEEE transactions on systems, man and cybernetics. 22(1992) no.5, S.865-884

0.008614248 = product of:
  0.017228495 = sum of:
    0.017228495 = product of:
      0.03445699 = sum of:
        0.03445699 = weight(_text_:22 in 5259) [ClassicSimilarity], result of:
          0.03445699 = score(doc=5259,freq=2.0), product of:
            0.1781178 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.05086421 = queryNorm
            0.19345059 = fieldWeight in 5259, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5259)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Date

22. 7.2006 14:26:01

0.008614248 = product of:
  0.017228495 = sum of:
    0.017228495 = product of:
      0.03445699 = sum of:
        0.03445699 = weight(_text_:22 in 5276) [ClassicSimilarity], result of:
          0.03445699 = score(doc=5276,freq=2.0), product of:
            0.1781178 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.05086421 = queryNorm
            0.19345059 = fieldWeight in 5276, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5276)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Date

22. 7.2006 16:14:37