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121.
Edward Humphreys 《Datenschutz und Datensicherheit - DuD》2011,35(1):7-11
This article presents ISO’s most successful information security standard ISO/IEC 27001 together with the other standards
in the family of information security standards — the socalled ISO/IEC 2700x family of information security management system
(ISMS) standards and guidelines. We shall take a brief look at the history and progress of these standards, where they originated
from and how became the common language of organizations around the world for engaging in business securely. We shall take
a tour through the different types of standard at are included in the ISMS family and how the relate and fit together and
we will finally conclude with a short presentation of ISMS third party certification. The material used in this article has
been derived directly from the many articles and books by Prof. Humphreys on the ISO/IEC 2700x ISMS family and they are implemented
and applied in practice in business, commerce and government sectors. 相似文献
122.
123.
Achieving stability at the site of femoral neck fracture is an important factor for callus formation in the post-operative period. However, measuring interfragmentary movement in vivo is not currently possible as telemetric screws have not been manufactured for surgical use. Understanding how the implantation of the screws can affect the stability of the fracture allows the surgeon to tailor the procedure to the patient and produce the best possible outcome. Two techniques have been developed that measure interfragmentary movement between fractured surfaces. The first was a FEA model of the proximal femur with screws represented by nodal links. Movement was quantified by the amount of relative motion occurring between paired nodes either side of the fracture. The second was a mechanical compression test of a composite femur that allowed the motion analysis of paired markers on the external surface of the femur. Movement was digitised with markers selected and displacements calculated by transforming the global coordinate system to a local system relative to the fracture plane. 相似文献
124.
125.
Linda A. Jackson Alexander von EyeHiram E. Fitzgerald Edward A. WittYong Zhao 《Computers in human behavior》2011,27(1):599-604
In this research we examined the prediction of children’s body mass index (BMI), body weight, academic performance, social self-esteem and overall self-esteem from their IT (information technology) use, specifically, their Internet use, cell phone use and videogame playing, after controlling for the effects of gender, race, age and household income on these measures. Participants were 482 children whose average age was 12 years old. One-third was African American and two-thirds were Caucasian American. Results indicated that IT use did not predict BMI or body weight, contrary to one previous survey and the widespread belief that screen time is responsible for the obesity epidemic among our nation’s children. Instead, BMI and body weight were higher for African Americans, older children and children from lower income households. The sole and strong positive predictor of visual-spatial skills was videogame playing, which also predicted lower grade point averages (GPAs). Gender and Internet use predicted standardized test scores in reading skills. Females and children who used the Internet more had better reading skills than did males and children who used the Internet less, respectively. Implications of these findings for future research on the benefits and liabilities of IT use are discussed. 相似文献
126.
The objective of the current research is to model trends in video game playing, overall computer use, and communication technology use in a longitudinal sample of youths, aged 11-16 over a 3-year interval. In addition, individual difference characteristics that may be predictive of these trends were included, namely, socio-demographic characteristics (gender, ethnicity, and parental income) and personality characteristics (self-esteem, the Big Five personality factors). Findings suggested that youth increased their overall computer and communication technology use but decreased their videogame playing over time. Many individual differences predicted mean levels of these technologies with fewer predicting slopes. Conclusions, implications, and limitations are discussed. 相似文献
127.
Camera distortion self-calibration using the plumb-line constraint and minimal Hough entropy 总被引:1,自引:0,他引:1
In this paper, we present a simple and robust method for self-correction of camera distortion using single images of scenes
which contain straight lines. Since the most common distortion can be modelled as radial distortion, we illustrate the method
using the Harris radial distortion model, but the method is applicable to any distortion model. The method is based on transforming
the edgels of the distorted image to a 1-D angular Hough space, and optimizing the distortion correction parameters which
minimize the entropy of the corresponding normalized histogram. Properly corrected imagery will have fewer curved lines, and
therefore less spread in Hough space. Since the method does not rely on any image structure beyond the existence of edgels
sharing some common orientations and does not use edge fitting, it is applicable to a wide variety of image types. For instance,
it can be applied equally well to images of texture with weak but dominant orientations, or images with strong vanishing points.
Finally, the method is performed on both synthetic and real data revealing that it is particularly robust to noise. 相似文献
128.
Tongqing Qiu Edward Chan Mao Ye Guihai Chen Ben Y. Zhao 《The Journal of supercomputing》2009,48(1):15-42
A self-organizing peer-to-peer system is built upon an application level overlay, whose topology is independent of an underlying
physical network. A well-routed message path in such systems may result in a long delay and excessive traffic due to the mismatch
between logical and physical networks. In order to solve this problem, we present a family of Peer-exchange Routing Optimization
Protocols (PROP) to reconstruct the overlay. It includes two policies: PROP-G for generic condition and PROP-O for optimized
one. Both theoretical analysis and simulation experiments show that these two protocols greatly reduce the average latency
of the overlay and achieve a better logical topology with low overhead. Their overall performance can be further improved
if combined with other recent approaches. Specifically, PROP-G can be easily applied to both structured and unstructured systems
without the loss of their primary characteristics, such as efficient routing and anonymity. PROP-O, on the other hand, is
more efficient, especially in a heterogenous environment where nodes have different processing capabilities.
相似文献
Edward ChanEmail: |
129.
Christian Collberg Andrew Huntwork Edward Carter Gregg Townsend Michael Stepp 《Information and Software Technology》2009,51(1):56-67
This paper presents an implementation of the watermarking method proposed by Venkatesan et al. in their paper [R. Venkatesan, V. Vazirani, S. Sinha, A graph theoretic approach to software watermarking, in: Fourth International Information Hiding Workshop, Pittsburgh, PA, 2001]. An executable program is marked by the addition of code for which the topology of the control-flow graph encodes a watermark. We discuss issues that were identified during construction of an actual implementation that operates on Java bytecode. We present two algorithms for splitting a watermark number into a redundant set of pieces and an algorithm for turning a watermark number into a control-flow graph. We measure the size and time overhead of watermarking, and evaluate the algorithm against a variety of attacks. 相似文献
130.
The use of separate transport and economic models in urban planning provides a limited view of economic impacts, restricts the testing of network design options and lengthens the planning process. Furthermore, the standard methodology for economic appraisal assumes partial economic equilibrium and cannot determine the distribution of impacts from the transport sector to households. Computable general equilibrium (CGE) models can capture general equilibrium effects and measure welfare at the household level, but mostly lack integration with transport models and do not represent all trip generators. This paper develops an integrated traffic assignment and spatial CGE model in nonlinear complementarity form, casted as a framework for economic appraisal of urban transport projects. The CGE submodel generates commuting, shopping and leisure trips as inputs into the transport submodel, which then assigns trips to the network according to user equilibrium. The resulting travel times then feed back into household prices and freight margins. Households and firms fully account for travel times in decisions on where to shop, how much labour to supply and where to source production inputs. Calibration and applications of the model are demonstrated for 14 regions and 2 industries across Sydney using GAMS/PATH on the NEOS server. The welfare of various network improvements is measured using equivalent variations. The model can be calibrated to external strategic transport models, and be extended to simulate additional trip generators and land-use. 相似文献