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11.
Industries in the US continue to lose ground in international competition. If IS is to help change that trend, it will have to become more creative. Creativity improvement programs are being introduced in other areas of the company— now is the time for IS organizations to follow suit.  相似文献   
12.
A clear understanding of the concept and consequences of diversity in science and technology is a key issue for Europe, when considering the current debate on cohesion Put forward within the Single European Act. According to Article 130B of the Single Act, all European policies, including technological policies must contribute to the achievement of a greater cohesion throughout the EC. The European market is generally presented as mainly a patchwork of national or even regional characteristics, with compartmentalized niches, and specific regulations. But does cohesion mean decreasing disparities between regions, which in such case signifies a passive policy of reallocation of resources within the EC, at the risk of generating uniformity? Or, does cohesion mean integration of all innovative and creative efforts, which implies a more complex policy of stimulation, under the condition to maintain a certain diversity? Must the governments systematically reduce diversity, or on the contrary must they enlarge diversity? How can they distinguish between negative and positive aspects of diversity? How do they operate a trade off between economies of scale and economies of diversity? To try to answer these political issues and to set up a coherent industrial policy at the EC level, a careful analysis of the sources of diversity, of the mechanisms that generate or reduce diversity, of the ways to valorize diversity are discussed in this paper  相似文献   
13.
Due to several inherent advantages, plasma processing technology may become a very useful tool in the production of new materials. An increasing research effort based on experimental as well as theoretical investigations has been invested in this area for the synthesis of advanced materials. In describing the thermal-plasma processing technique, this article employs examples from research at the Plasma Processing Laboratory at the University of Idaho.  相似文献   
14.
This paper reports the effect of humidity and temperature on the adhesive strength of a pressure sensitive adhesive (Flexbond 150) used to bond Mylar films. It has been found that, ill general, the adhesive strength decreases significantly with an increase in temperature. The effect of humidity on the bonding strength, however, was found to be process dependent. The sample preparation conditions, e.g., press weight for the bonding and the press time, are important in determining the humidity effect. The water sorption isotherm A 24°C for the adhesive was also determined. The amount of water sorbed by the adhesive at 95 percent relative pressure was found to be less than one weight percent.  相似文献   
15.
Definition of the problem: Ethical reasoning cannot be enforced. Voluntary understanding is a basic condition for the development of ethical competencies and attitudes. The aim of this survey was to investigate whether the presence of those students who attended our seminars compulsorily would have a negative effect upon the quality of the course. Methods and results: The participants of our small-group seminars in medical ethics were asked to complete a questionnaire on teaching aims, seminar atmosphere, moderation and importance of subjects. One hundred and ninety-two voluntary participants (2001/2) and 293 compulsory participants (2002/3) completed the questionnaire and were statistically compared. There was no significant difference between voluntary and compulsory participants in any of the important items. However, there were considerable differences in some items between male and female participants. Conclusion: We were surprised that there was no difference between the two groups. This leads us to hope that our concept of case-based small-group seminars will prove capable of realising our teaching aims for all students. The difference between male and female participants may have important didactic consequences and will be the subject of further studies.  相似文献   
16.
17.
Partially stabilized zirconia (PSZ) /β-alumina composites exhibit extensive non-elastic deformation during fracture. Repeated loading/stable fracture/unloading experiments were performed on chevron-notched four-point-bend specimens of the composite and pure PSZ. The energy consumption during the propagation of long cracks in the composite (∼500 J/m2) is 1 order of magnitude larger than for PSZ (∼50 J/m2). Breaking strengths of 127 MPa were obtained with a Weibull modulus of 43.  相似文献   
18.
This article presents a GRID framework for distributed computations in the chemical process industries. We advocate a generic agent-based GRID environment in which chemical processes can be represented, simulated, and optimized as a set of autonomous, collaborative software agents. The framework features numerous advantages in terms of scalability, software reuse, security, and distributed resource discovery and utilization. It is a novel example of how advanced distributed techniques and paradigms can be elegantly applied in the area of chemical engineering to support distributed computations and discovery functions in chemical process engineering. A prototype implementation of the proposed framework for chemical process design is presented to illustrate the concepts.  相似文献   
19.
Microcellular polymeric materials can be obtained by the polymerization of a high‐internal‐phase emulsion. These materials are good candidates as targets toward inertial confinement fusion. This application requires severe specifications, including a very low density and a small cell size. In this study, we examined the influence of parameters such as emulsification conditions, surfactant nature, and the presence of a porogen on the obtainment of those requirements. It was possible to obtain microcellular polymeric foams with apparent densities as low as 0.0126 g/cm3. However, it was difficult to obtain very low material density and still maintain a small average pore size. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2053–2063, 2005  相似文献   
20.
The main objective of the present work is to modify the traditional mapping method for the simulation of distributive mixing of multiphase flows in geometries involving moving parts such as, internal mixers or twin-screw extruders without a limitation on their geometrical periodicity. The periodicity condition, limits the results of traditional mapping method to tracking mapping mesh between specific discrete time intervals or distances for that geometry is repeated, hence, result is only for fixed orientation of rotors. Imaginary domain method is introduced to track mapping mesh from one state to the next free of geometrical periodicity limitations. In this work the method is introduced and its applicability and accuracy is discussed in details. A two-dimensional (2D) simulation of mixing of two Newtonian fluids with different viscosities in an intermeshing internal mixer is used as a test case study. In this example the key issues of ability to predict mixing state in details for all orientations of rotors is presented. To reduce diffusion errors of mapping method in the boundaries of the rotors, mapping mesh refinement technique that relies upon one single reference mesh is also presented.  相似文献   
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