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131.
A strict solution to the differential equation for the interaction between the falling mass and flat test specimen in the instrumented puncture test is developed here. This solution makes it possible to assess the error in the approximation equations for damaging energy and damaging deformation based on the reduced energy theorem, which are given in the literature for impact test evaluation. A further simplification of the evaluation formula for damaging deformation can be obtained for example by assuming a parabolic curve for falling mass velocity during penetration. The evaluation can then be carried out with a non-programmable pocket calculator. The curve-shape-dependent error is generally around 1% or less as tests with some 103 sets of 10 flat test specimens made from a range of different polymers confirm. This approximation has been incorporated in the ISO draft standard for the instrumented puncture test on flat test specimens (Draft Proposal DP 6603/2 ?Plastics — Determination of multiaxial impact behaviour of rigid plastics — part 2: instrumented puncture test”?).  相似文献   
132.
PROven(R)系统的开发 为了减少焦炉的排放,过去已进行了多种技术的开发.但是从焦炉炉门、装料孔边缘等处逸散物的减少,已受到工艺技术的制约.一个基本的制约因素是,在集气总管内的压力和联接到总管的所有碳化室内的压力之间有着密不可分的关系.  相似文献   
133.
We describe a distributed high-performance compute server that has been implemented for running compute-intensive applications on a mixture of HPC systems interconnected by Inter-and Intranet. With a practical industrial background, our work focusses on high availability, efficient job load balancing, security, and the easy integration of HPC computing into the daily work-flow at pharmaceutical companies.

The work was done in the course of the ESPRIT project P A Distributed Pharmaceutical Application Server The client software is implemented in Java. All results are displayed in a web browser and can be forwarded to the next stage of applications used in the drug design cycle. The server software handles the job load balancing between the participating HPC nodes and is capable of managing multi-site applications.

Our environment currently supports four key applications that are used in rational drug design and drug target identification. They range from the automatic functional annotation of protein sequences to three-dimensional protein structure prediction tools and protein comparison applications.  相似文献   

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135.
Representation techniques are important issues when designing successful evolutionary algorithms. Within this field the use of neutrality plays an important role. We examine the use of bit-wise neutrality introduced by Poli and López (2007) from a theoretical point of view and show that this mechanism only enhances mutation-based evolutionary algorithms if not the same number of genotypic bits for each phenotypic bit is used. Using different numbers of genotypic bits for the bits in the phenome we point out by rigorous runtime analyses that it may reduce the optimization time significantly.  相似文献   
136.
The behavior of nanostructured and submicrometer α-Al2O3 powders during the initial stages of field-assisted sintering technique (FAST), conventional, and microwave sintering was investigated using the laser-flash technique for thermo-optical measurements (TOM). An enhanced neck formation due to surface diffusion at very early stages of sintering was found in FAST samples. No significant difference due to heating rate has been found in these various samples.  相似文献   
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138.
Grid tariffs are the main source of income for distribution system operators (DSOs). Reductions of tariffs increase the cost pressure on DSOs; assuming they work efficiently, tariff reductions potentially lead to a decrease of the electricity system's quality if no reliability of supply criteria are incorporated in the regulatory system. Our statistical analysis shows that the correlation between grid tariffs and electricity supply interruptions in a regulatory regime neglecting this incorporation is significant and that furthermore decreasing tariffs harm the reliability of supply even in the short run. Our econometric analysis of the influence of tariffs on reliability of supply shows a significant correlation between the grid tariffs and the duration of power outages in the Austrian electricity grid; an annual average interruption duration per installed capacity of a specific grid increases ceteris paribus by 1.36 min if the grid tariff of this specific grid is decreased in the previous year by 1€/MWh.  相似文献   
139.
Increased computer speed has helped to proliferate tomography throughout the geosciences. Although best known from the medical CATscan, tomography is also a powerful tool for geological problems. Whereas qualitative tomography is widely used, quantitative data from tomograms are not so commonly available. Presented here are two programs, Electron Tomography Segmentation, surface Area, and Volume (ETSAV) and Electron Tomography CUTter (ETCut), that were written to obtain quantitative volume and surface-area data from tomograms. Based on a specified threshold value, ETSAV distinguishes objects within a tomogram and then returns volume and surface-area data for each object. If object separation is unsatisfactory using a single threshold, ETCut is called to digitally separate objects that appear connected in the tomogram, allowing ETSAV to perform its functions. By knowing the nature of the object of interest, error can be corrected to, on average, less than 5% for a single object; combined volumes of many particles of different sizes may result in lesser errors. A section of the Brenham pallasite meteorite was examined using the programs. Olivine comprises 67.2% of the volume (50.4% wt%), followed by FeNi metal at 23.1% (39.3% wt%), troilite at 4.4% (4.8% wt%), and schreibersite at 3.4% (5.5% wt%). In all, 56.1% and 44.7% of the troilite and schreibersite surface areas, respectively, border olivine, suggesting that they wet olivine. Since the programs can be applied to any tomogram, from any field, there are many potential applications.  相似文献   
140.
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