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1.
The seriousness of computer hacking is not exaggerated, it is far worse than that. The computer hacker has attained the status of myth; society associates all computer crime with a mythical perpetrator that bears no resemblance to reality. This paper will argue that in the early stages of the myth the computer hacker was regarded as a highly skilled but mentally disturbed youth who has an unhealthy association with computers. The new reality of electronic commerce resulted in pressures that culminated in the computer hacker becoming regarded as a dangerous criminal. A thorough analysis of the statistics will demonstrate that the majority of computer intruders are neither dangerous nor highly skilled, and thus nothing like the mythical hacker.  相似文献   
2.
计算机辅助教学是传统教学模式的一个根本性变革 ,在高等教育中发挥的作用越来越明显。探讨了在进行计算机辅助教学课件 (CAI)的开发过程中 ,当前普遍存在的问题及其产生的原因 ,同时 ,初步提出了解决这些问题的方法 ,指出 CAI课件应向网络化、智能化方向发展  相似文献   
3.
Quantifying uncertainty in the biospheric carbon flux for England and Wales   总被引:1,自引:0,他引:1  
Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO2) concentrations in the atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 1012 g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.  相似文献   
4.
本文介绍了杭州汽轮机厂计算机集成制造系统HTW-CIMS的总体方案以及开发和应用该系统时遵循的技术路线。  相似文献   
5.
高校扩招下工程图学的教学实践与探讨   总被引:1,自引:1,他引:0  
文章分析了高校扩招给工程图学教学带来的困难 ,并实践和探讨了一种在保证教学质量的前提下提高教学效率的现代教学模式  相似文献   
6.
In electrical engineering, circuit designs are now often optimized via circuit simulation computer models. Typically, many response variables characterize the circuit's performance. Each response is a function of many input variables, including factors that can be set in the engineering design and noise factors representing manufacturing conditions. We describe a modelling approach which is appropriate for the simulator's deterministic input–output relationships. Non-linearities and interactions are identified without explicit assumptions about the functional form. These models lead to predictors to guide the reduction of the ranges of the designable factors in a sequence of experiments. Ultimately, the predictors are used to optimize the engineering design. We also show how a visualization of the fitted relationships facilitates an understanding of the engineering trade-offs between responses. The example used to demonstrate these methods, the design of a buffer circuit, has multiple targets for the responses, representing different trade-offs between the key performance measures.  相似文献   
7.
Identical numerical integration experiments are performed on a CYBER 205 and an IBM 3081 in order to gauge the relative performance of several methods of integration. The methods employed are the general methods of Gauss-Legendre, iterated Gauss-Legendre, Newton-Cotes, Romberg and Monte Carlo as well as three methods, due to Owen, Dutt, and Clark respectively, for integrating the normal density. The bi- and trivariate normal densities and four other functions are integrated; the latter four have integrals expressible in closed form and some of them can be parameterized to exhibit singularities or highly periodic behavior. The various Gauss-Legendre methods tend to be most accurate (when applied to the normal density they are even more accurate than the special purpose methods designed for the normal) and while they are not the fastest, they are at least competitive. In scalar mode the CYBER is about 2-6 times faster than the IBM 3081 and the speed advantage of vectorised to scalar mode ranges from 6 to 15. Large scale econometric problems of the probit type should now be routinely soluble.  相似文献   
8.
医学人文教育应该贯穿于医学院校的全部教学环节当中,其教育目标和内容适宜融入"思想道德修养与法律基础"课程。在体现"基础"课教学大纲的基础上,依章节添加医学人文教育内容;并根据学科特点采用医学特色教学方法。新教学班级与传统教学班级的对比研究表明,新教学班级在课堂教学效果与期末考试成绩方面成效显著。  相似文献   
9.
ABSTRACT

The effectiveness of a bilingual (English/Spanish) computer-assisted alcohol screening/intervention for hazardous and harmful alcohol use, the Health Habits Survey (HHS) was tested in primary care settings. Assessment-only patients were compared with patients exposed to the HHS. Of the 2053 recruited, 151 (7.4%) screened positive on the Alcohol Use Disorders Identification Test (AUDIT) and were re-contacted six months later for follow-up. Significant alcohol reduction was observed in both conditions. No between-group differences were observed. Computer-assisted screening and intervention are feasible in primary care settings and may be a realistic provider-extender when traditional screening is absent or inconsistently implemented.  相似文献   
10.
Computer models with functional output are omnipresent throughout science and engineering. Most often the computer model is treated as a black-box and information about the underlying mathematical model is not exploited in statistical analyses. Consequently, general-purpose bases such as wavelets are typically used to describe the main characteristics of the functional output. In this article we advocate for using information about the underlying mathematical model in order to choose a better basis for the functional output. To validate this choice, a simulation study is presented in the context of uncertainty analysis for a computer model from inverse Sturm-Liouville problems.  相似文献   
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