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41.
本文对几种典型减振器做了一些分析,并根据我国主战坦克的特点提出了一种新的改进设计方案,在文中暂称为“复合作用”式减振器。它既能产生象摩擦减振器的摩擦阻尼,又能具有筒式减振器的小孔节流阻尼效果。两种阻尼的复合作用如调整适当,则对提高悬挂系统对地面情况的变化适应能力,改善车辆行驶平稳性和可靠性有很大的帮助。  相似文献   
42.
Utilizing the existing properties of steel, a modern technological society has been constructed. While there are over 25,000 worldwide equivalent steels based on manipulating the eutectoid transformation, there exist only a handful of commercial nanostructured steel alloys based on manipulating the more complex glass devitrification transformation. Thus, research on nanostructured steels is in its infancy, and many further developments are expected with the demonstrated promise of developing new combinations of superior properties. In this article, seven enabling metallurgical factors are presented that ultimately allow a variety of nanostructured steel products to be produced in an ever-increasing array of industrial processing techniques. Additionally, a case example of the formation of nanostructured steel are given showing how these factors can be harnessed on an industrial scale.  相似文献   
43.
郑银环  张仲甫 《机床与液压》2005,(3):107-108,51
讨论了渐变刚度钢板弹簧的载荷、变形量、刚度和应力的计算,建立了少片渐变刚度钢板弹簧的优化数学模型,利用MATLAB优化工具箱进行优化,并给出了计算实例。  相似文献   
44.
水性聚氨酯材料配方设计技巧   总被引:1,自引:1,他引:1  
介绍了优选法的0.618法和分数法,对其进行改进创新和原理证明,并应用于生产涂料配方设计中。  相似文献   
45.
阐述了设计院拥有技术和开发技术的重要性及获取技术的途径,并详细介绍了设计人员能够开展的技术开发工作。  相似文献   
46.
We present a simple and fast algorithm to test the thermodynamic stability and determine the necessary chemical environment for the production of a multiternary material, relative to competing phases and compounds formed from the constituent elements. If the material is found to be stable, the region of stability, in terms of the constituent elemental chemical potentials, is determined from the intersection points of hypersurfaces in an (n−1)(n1)-dimensional chemical potential space, where nn is the number of atomic species in the material. The input required is the free energy of formation of the material itself, and that of all competing phases. Output consists of the result of the test of stability, the intersection points in the chemical potential space and the competing phase to which they relate, and, for two- and three-dimensional spaces, a file which may be used for visualization of the stability region. We specify the use of the program by applying it both to a ternary system and to a quaternary system. The algorithm automates essential analysis of the thermodynamic stability of a material. This analysis consists of a process which is lengthy for ternary materials, and becomes much more complicated when studying materials of four or more constituent elements, which have become of increased interest in recent years for technological applications such as energy harvesting and optoelectronics. The algorithm will therefore be of great benefit to the theoretical and computational study of such materials.  相似文献   
47.
Despite the apparent maturity of the learning design field, and the variety of tooling available to support it, adoption among the teacher community (one of its alleged main targets) is still low. There is a lack of research on teachers' perception and use of different technological learning design tools, as existing evaluations are often restricted to a single tool. In order to explore whether there are common factors hampering teacher adoption, and which tool features might appeal to different teachers, more studies involving multiple authoring tools are needed. This paper provides a first step in this direction, describing a mixed methods study performed around a professional development workshop with 18 university teachers from multiple disciplines. This workshop exposed teachers to two different authoring tools (WebCollage and EDIT2), as they learned to create computer-supported collaborative learning (CSCL) designs and implement them. The findings of our interpretive study (which included questionnaires, observations, or group discussion recordings) support the idea that there is no single tool or set of features that are globally perceived as better, although our evidence also highlights certain factors as important for participant teachers – amongst others, the integration of learning designs with the ICT platforms for enactment, as well as with other tools that they already use in their everyday practice.  相似文献   
48.
The secure operation of autonomous vehicle networks in the presence of adversarial observation is examined, in the context of a canonical double-integrator-network (DIN) model. Specifically, we study the ability of a sentient adversary to estimate the full network’s state, from noisy local measurements of vehicle motions. Algebraic, spectral, and graphical characterizations are provided, which indicate the critical role of the inter-vehicle communication topology and control scheme in achieving security.  相似文献   
49.
Defining appropriate pricing strategy for smart environment is important and complex task at the same time. It holds the primal fraction in Demand Response (DR) program. In our work, we devise an incentive based smart dynamic pricing scheme for consumers facilitating a multi-layered scoring rule. The proposed strategy characterizes both incentive based DR and price based DR programs facilities. This mechanism is applied between consumer agents (CA) to electricity provider agent (EP) and EP to Generation Company (GENCO). Based on the Continuous Ranked Probability Score (CRPS), a hierarchical scoring system is formed among these entities, CA–EP–GENCO. As CA receives the dynamic day-ahead pricing signal from EP, it will schedule the household appliances to lower price period and report the prediction in a form of a probability distribution function to EP. EP, in similar way reports the aggregated demand prediction to GENCO. Finally, GENCO computes the base discount after running a cost-optimization problem. GENCO will reward EP with a fraction of discount based on their prediction accuracy. EP will do the same to CA based on how truthful they were reporting their intentions on device scheduling. The method is tested on real data provided by Ontario Power Company and we show that this scheme is capable to reduce energy consumption and consumers’ payment.  相似文献   
50.
When priorities to message streams are assigned using Rate Monotonic (RM) for a Controller Area Network (CAN), the utilization bound is known to be about 25% for CAN 2.0A and 29% for CAN 2.0B. In this letter, we present a higher utilization bound than the existing ones with a reasonable constraint. The new utilization bounds are approximately 34% for CAN 2.0A and 41% for CAN 2.0B if no single message stream's utilization exceeds 46% or 27% of the total utilization for CAN 2.0A or CAN 2.0B, respectively.  相似文献   
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