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1.
Abstract— In order to lower development costs and to shorten development time, small panels, under 10‐in on the diagonal, are used for the experiments to improve the luminous efficiency of plasma‐display panels. However, it is difficult to show the same results as those of large panels, over 40 in. on the diagonal. In this paper, first, we show that the luminous efficiency and the voltage margin of mini‐panels are not obtained with large panels by using an actual 46‐in. PDP. The reason is that the resistance in the large panels is larger than that in the mini panels and the voltage drop in the large panels are larger than in mini‐panels. Therefore, we conclude that the bus electrode width and the transparent electrode width are important factors in the design of large PDPs. Next, we show the technique of designing large panels by using a database obtained from mini‐panels. The estimated cell‐design results show good agreement with an actual 46‐in. PDP in luminous efficiency and minimum sustain voltage. We show that a desired large PDP can be obtained by using the cell design proposed in the present paper.  相似文献   

2.
The facial fit of respirators is crucial for determining how effectively respirators may protect users from exposure to airborne contaminants, when their use is required in the workplace. In the Chilean market, all the respirators available have been designed and manufactured using foreign regulations. The aim of this research was to determine the facial dimensions in a sample of Chilean workers (users or potential users of respiratory protective equipment) and the possible mismatch between their anthropometric characteristics and the respirator fit test panels proposed by Los Alamos National Laboratory (LANL) and National Institute for Occupational Safety and Health (NIOSH). An anthropometric survey that included 11 measurements was conducted, based on ISO/TS 16976–2 and ISO 15535 to ensure the highest standards possible, and a total of 474 workers (female: 229, male: 245), aged 18–66 years old participated in the survey. The anthropometric measurements were then contrasted with the fit test panels used in LANL (for half and full facepieces) and NIOSH (Bivariate and Principal component analysis (PCA)), to verify the level of mismatch. The results showed that LANL panels presented a level of mismatch of 11.8% and 21% for the half-facepiece and the full-facepiece, respectively. Considering the NIOSH bivariate and PCA panels, 4.6% and 4.4% of the sample remains without an assigned cell, respectively. It can be concluded that the LANL panels for half and full facepieces do not match the facial dimensions of the Chilean working population. The panels developed by NIOSH and considered by the ISO/TS 16976–2 (bivariate and PCA), are applicable to the Chilean working population.Relevance for the IndustryThis research provides anthropometric measurements of Chilean workers, to determine the dimensions for half- and full-facepiece respirators, which are currently not available. The NIOSH or ISO fit test panels, as opposed to LANL panels, should be used when manufacturing respirators for Chilean workers.  相似文献   

3.
This paper addresses the issue of system identification for an active-head slider used to form a stable and reliable head–disk interface with a spacing of sub 3?nm. A new identification method is proposed to fit the highly non-stationary and highly nonlinear slider dynamics. The estimated model can be used for design of a model based nonlinear controller to control the flying height within the desired range. The effectiveness of the proposed system identification method is verified with simulation examples.  相似文献   

4.
This work deals with design sensitivity analysis and optimal design of composite structures modelled as thin-walled beams. The structures are treated as a torsion-bending resistant beams. The analysis problem is discretized by a finite element technique. A two-node Hermitean beam element is used. The beam sections are made from an assembly of elements that correspond to flat layered laminated composite panels. Optimal design is performed with respect to the lamina orientations and thickness of the laminates. The structural weight is considered as the objective function. Constraints are imposed on stresses, displacements, critical load and natural frequencies. Two failure criteria are used to limit the structural strength: Tsai-Hill and maximum stress. The Tsai-Hill criterion is also adopted to predict the first-ply-failure loads. The design sensitivity analysis is analytically formulated and implemented. An adjoint variable method is used to derive the response sensitivities with respect to the design. A mathematical programming approach is used for the optimization process. Numerical examples are performed on three-dimensional structures.  相似文献   

5.
For creative products, maintaining original brand elements and features in a new product is an important issue in the design process as brand features are conceived and generated for longevity. However, current methods rely on designers’ abilities, and the size of forms is easily affected when shape morphing is applied, causing limitations in computer-aided design. In order to focus on design while preserving key features, a systematic method for presenting brand features is proposed in this article. In this method, the feature curves of the brand features of a company are decomposed with defined feature parameters, which were then used to reconstruct the feature curve of the designed product in the design stage by using a residual modified gray prediction model. A classic vehicle configuration design is taken as an example to show the implementation procedure of the proposed method. With residual modification, this method can also assimilate other forms from the original form database, and generate new forms based on gray prediction. The results show that brand features can be retained in the newly designed product based on the proposed method. Though vehicle design is taken as the example, this method can also be used to develop designs for many other the brand features. For classic products with historical value, this method can generate new forms that maintain original brand features, thereby satisfying customers’ needs for brand authenticity.  相似文献   

6.
This paper addresses the issue of system identification and controller design for an active-head slider used to form a stable and reliable head-disk interface with a spacing of sub 3?nm. A new identification method is proposed to fit the highly non-stationary and highly nonlinear slider dynamics. The estimated model is then used for the design of a model based nonlinear controller to control the flying height within the desired range. The effectiveness of the proposed system identification method and the nonlinear controller is verified with simulation examples.  相似文献   

7.
A novel multi-objective genetic algorithm (GA)-based rule-mining method for affective product design is proposed to discover a set of rules relating design attributes with customer evaluation based on survey data. The proposed method can generate approximate rules to consider the ambiguity of customer assessments. The generated rules can be used to determine the lower and upper limits of the affective effect of design patterns. For a rule-mining problem, the proposed multi-objective GA approach could simultaneously consider the accuracy, comprehensibility, and definability of approximate rules. In addition, the proposed approach can deal with categorical attributes and quantitative attributes, and determine the interval of quantitative attributes. Categorical and quantitative attributes in affective product design should be considered because they are commonly used to define the design profile of a product. In this paper, a two-stage rule-mining approach is proposed to generate rules with a simple chromosome design in the first stage of rule mining. In the second stage of rule mining, entire rule sets are refined to determine solutions considering rule interaction. A case study on mobile phones is used to demonstrate and validate the performance of the proposed rule-mining method. The method can discover rule sets with good support and coverage rates from the survey data.  相似文献   

8.
在小型太阳能光伏-热伏发电系统中,为了提高其发电效率,通常会辅以自动追光系统;针对现有的基于多光电二极管的自动追光系统结构复杂等问题,提出了一种基于光敏电阻的自适应追光系统;为了实现发电板对光源的追踪,采用了基于负反馈的自适应追光原理,通过软件设计控制追光精度,同时增加了系统位置消抖控制;在硬件方面,采用光敏电阻感应光强,借助AD转换电路和舵机,以驱动太阳能光伏-热伏发电板转动直至发电板平面垂直于太阳光;优化设计了光敏电阻与板面的夹角大小以调整追光的区域及误差;最后完成了整体装置的机械结构设计和电路图设计及仿真;结果表明,与现有的多光电二极管追光系统相比,所设计的追光系统机械装置部分的设计更加简单,便于实现,同时通过优化设计改善了追光的稳定性。  相似文献   

9.
航天器帆板展开过程动力学建模与仿真   总被引:2,自引:0,他引:2  
阐述了应用柔性多体动力学和Kane方程进行航天器帆板展开过程建模的方法,将帆板视为柔性体并进行模态分析,采用有限元法与模态缩聚技术建立了帆板的离散化模型.以国产某型号航天器为例,同时考虑4块帆板的柔性,应用ADAMS软件对帆板的展开过程进行了建模与仿真,得到了帆板的变形、大范围运动等动力学参量,为航天器帆板的设计提供了一定的依据.  相似文献   

10.
Mass customization of products that interface with the human body poses unique problems due to the complexities of bio-interface design, the lack of biomechanical techniques in traditional mechanical design, and the absence of specific parametric strategies. Current biomechanical design often follows craftsman-like design processes using less than state-of-the-art tools and techniques. Thus, products that interface with the human body are not readily parameterized or automated. This paper presents a strategy for implementing mass customization in the design of mechanical devices that interface with the human body. This strategy is based on three methods that include: a method for capturing and representing the human body so that the model can be used with state-of-the-art tools and solid modeling techniques, a design methodology based on feature structure planning allowing the design process to be reused and automated, and a strategy for identifying parametric variables tied to the human body. A case study is presented to illustrate the proposed process.  相似文献   

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