3,361 research outputs found

    Employment-Based Preferences Categories: An Effort to Simplify Has Resulted in More Paperwork

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    With the passage of the Immigration Act of 19901 ( the Act ), employment-based and family-sponsored immigration underwent sweeping and dramatic reforms. By implementing new criteria for both these areas of immigration, the Act sought to realize its new policy of strengthening American competitiveness in the global economy and to reinforce its prior policy of favoring family reunification. The Act, which was signed into law by President Bush on November 29, 1990, and went into effect on October 1, 1991, represents the culmination of a decade-long reform process that began with the Select Commission on Immigration and Refugee Policy in 1979. The resulting legislation represents the most comprehensive revision of United States immigration law in sixty-six years, and like previous attempts at immigration reform, the goals of the 1990 Act may be difficult to carry into practice

    Political Will Needed to Effectively and Efficiently Conserve and Manage Water in India

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    Dr. Mansee Bal Bhargava, a research entrepreneur at the Environment Design Consultants (EDC), Ahmedabad, and a former Fulbright scholar at Centre for Behaviour, Institutions, and Environment, School of Sustainability, Arizona State University, Tempe (2016-17) — has written an open letter on behalf of water allied researchers, educators, consultants, and enthusiasts*, titled “Water Matters: Appeal for Election 2019 Onward”

    Visualization of Wormholes in Sensor Networks

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    Several protocols have been proposed to defend against wormholes in ad hoc networks by adopting positioning devices, synchronized clocks, or directional antennas. In this paper, we propose a mechanism, MDS-VOW, to detect wormholes in a sensor network. MDS-VOW first reconstructs the layout of the sensors using multi-dimensional scaling. To compensate the distortions caused by distance measurement errors, a surface smoothing scheme is adopted. MDS-VOW then detects the wormhole by visualizing the anomalies introduced by the attack. The anomalies, which are caused by the fake connections through the wormhole, bend the reconstructed surface to pull the sensors that are faraway to each other. Through detecting the bending feature, the wormhole is located and the fake connections are identified. The contributions of MDS-VOW are: (1) it does not require the sensors to be equipped with special hardware, (2) it adopts and combines the techniques from social science, computer graphics, and scientific visualization to attack the problem in network security. We examine the accuracy of the proposed mechanism when the sensors are deployed in a circle area and one wormhole exists in the network. The results show that MDS-VOW has a low false alarm ratio when the distance measurement errors are not large

    Cryptanalysis of an MPEG-Video Encryption Scheme Based on Secret Huffman Tables

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    This paper studies the security of a recently-proposed MPEG-video encryption scheme based on secret Huffman tables. Our cryptanalysis shows that: 1) the key space of the encryption scheme is not sufficiently large against divide-and-conquer (DAC) attack and known-plaintext attack; 2) it is possible to decrypt a cipher-video with a partially-known key, thus dramatically reducing the complexity of the DAC brute-force attack in some cases; 3) its security against the chosen-plaintext attack is very weak. Some experimental results are included to support the cryptanalytic results with a brief discuss on how to improve this MPEG-video encryption scheme.Comment: 8 pages, 4 figure
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