Logistic Regression Analysis of Customer Satisfaction Data

Variation exists in all processes. Significant work has been done to identify and remove sources of variation in manufacturing processes resulting in large returns for companies. However, business process optimization is an area that has a large potential return for a company. Business processes can be difficult to optimize due to the nature of the output variables associated with them. Business processes tend to have output variables that are binary, nominal or ordinal. Examples of these types of output include whether a particular event occurred, a customer's color preference for a new product and survey questions that assess the extent of the survey respondent's agreement with a particular statement. Output variables that are binary, nominal or ordinal cannot be modeled using ordinary least‐squares regression. Logistic regression is a method used to model data where the output is binary, nominal or ordinal. This article provides a review of logistic regression and demonstrates its use in modeling data from a business process involving customer feedback. Copyright © 2006 John Wiley & Sons, Ltd.     

B737机务CBT系统建设方案的探讨

通过对AICC制订的CBT课件开发规范的探讨，阐述了CBT的基本概念和波音737飞机机务CBT的开发制作过程，以及利用Authorware开发软件制作多媒体课件的技术难点。     

A framework to integrate software behavior into dynamic probabilistic risk assessment

Software plays an increasingly important role in modern safety-critical systems. Although, research has been done to integrate software into the classical probabilistic risk assessment (PRA) framework, current PRA practice overwhelmingly neglects the contribution of software to system risk. Dynamic probabilistic risk assessment (DPRA) is considered to be the next generation of PRA techniques. DPRA is a set of methods and techniques in which simulation models that represent the behavior of the elements of a system are exercised in order to identify risks and vulnerabilities of the system. The fact remains, however, that modeling software for use in the DPRA framework is also quite complex and very little has been done to address the question directly and comprehensively. This paper develops a methodology to integrate software contributions in the DPRA environment. The framework includes a software representation, and an approach to incorporate the software representation into the DPRA environment SimPRA. The software representation is based on multi-level objects and the paper also proposes a framework to simulate the multi-level objects in the simulation-based DPRA environment. This is a new methodology to address the state explosion problem in the DPRA environment. This study is the first systematic effort to integrate software risk contributions into DPRA environments.     

Automating application software generation

Many approaches have been proposed to enhance software productivity and reliability. These approaches typically fall into three categories: the engineering approach, the formal approach and the knowledge-based approach. But the optimal gain in software productivity cannot be obtained if one relies on only one of these approaches. This paper describes the work in knowledge-based software engineering conducted by the authors for the past 10 years. The final goal of the research is to develop a paradigm for software engineering which integrates the three approaches mentioned above. A knowledge-based tool which can support the whole process of software development is provided in this paper.     

Education-driven research in CAD

We argue for a new research category, named education-driven research (EDR), which fills the gap between traditional field-specific research that is not concerned with educational objectives and research in education that focuses on fundamental teaching and learning principles and possibly on their customization to broad areas (such as mathematics or physics), but not to specific disciplines (such as CAD). The objective of EDR is to simplify the formulation of the underlying theoretical foundations and of specific tools and solutions in a specialized domain, so as to make them easy to understand and internalize. As such, EDR is a difficult and genuine research activity, which requires a deep understanding of the specific field and can rarely be carried out by generalists with primary expertise in broad education principles. We illustrate the concept of EDR with three examples in CAD: (1) the Split and Tweak subdivisions of a polygon and its use for generating curves, surfaces, and animations; (2) the construction of a topological partition of a plane induced by an arbitrary arrangement of edges; and (3) a romantic definition of the minimal and Hausdorff distances. These examples demonstrate the value of using analogies, of introducing evocative terminology, and of synthesizing the simplest fundamental building blocks. The intuitive understanding provided by EDR enables the students (and even the instructor) to better appreciate the limitations of a particular solution and to explore alternatives. In particular, in these examples, EDR has allowed the author to: (1) reduce the cost of evaluating a cubic B-spline curve; (2) develop a new subdivision curve that is better approximated by its control polygon than either a cubic B-spline or an interpolating 4-point subdivision curve; (3) discover how a circuit inclusion tree may be used for identifying the faces in an arrangement; and (4) rectify a common misconception about the computation of the Hausdorff error between triangle meshes. We invite the scientific community to encourage the development of EDR by publishing its results as genuine research contributions in peer-reviewed professional journals.     

Surface segregation studied by low-energy ion scattering: experiment and numerical simulation

The changes in surface composition of metallic alloys caused by segregation can be very efficiently studied by low-energy ion scattering (LEIS) due to the specific surface sensitivity of this technique. Investigations of single-crystal surfaces of ordered alloys are of particular interest because they provide the possibility to investigate the interplay between segregation effects and the order-disorder phase transition when passing through the transition temperature. Exemplifying these effects for bimetallic alloys we consider in particular the CuAu-system.For the quantitative interpretation of energy and angle resolved LEIS intensity distributions we compare experimental results with those from numerical simulations using the MARLOWE code which we extended with a detailed trajectory analysis. This allows us to apply various discrimination criteria, such as number of collisions, distance of closest approach, identification of the scattering crystal layer, total path length, etc. On this basis structural effects, ion survival probabilities and the influence of thermal vibrations can be studied.We demonstrate this potential by using CuAu(1 0 0) as a special example. The scattering potential parameters were calibrated with elemental single crystals of known structures and the anisotropic Debye temperatures taken from the literature showed good agreement, neutralization was of minor importance in this case. Our procedure could be successfully used for the quantitative analysis of the composition of the first and second layer as a function of temperature. These results are in good agreement with theoretical predictions.     

生产系统的计算机仿真研究

生产系统在设计与运行过程中面临着诸多的问题需要解决，计算机仿真技术作为一种有效验证生产系统设计合理性和辅助生产管理决策的手段，近年来在我国得到了越来越广泛的关注。该文系统总结了计算机仿真技术对生产系统的重要作用，利用Ithink5.0软件建立了简单生产过程的计算机仿真模型并进行了分析。     

引水发电系统无压隧洞中弃水堰位置的数值模拟研究

水电站引水发电系统无压隧洞中的水力过渡过程是近年来电站设计中出现的一个新课题,特别是流域梯级电站开发中经常遇到。结合工程实例应用扩散法,给出了无压隧洞水力过渡过程数值模拟的基本方程以及上下游及弃水堰等边界附加方程,模拟了弃水堰布置在不同位置下,无压隧洞内的水位变化过程。研究成果和讨论对实际工程应用具有参考意义。