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101.
Jun-Shuw Lin 《Applied Soft Computing》2012,12(6):1733-1740
The clustering phenomenon of defects usually occurs in semiconductor manufacturing. However, previous studies did not pay much attention to the influence of clustering phenomenon for estimating fraction nonconforming of a wafer. Thus, this paper presents a systematic estimation model with considering relevant variables about clustering defects for fraction nonconforming of a wafer. The method combines back-propagation neural network (BPNN) with genetic algorithm (GA) to obtain an estimation model. In this study, GA aims to optimize the parameters of BPNN. Five relevant variables: number of defects (ND), squared coefficient of angle variation (SCVA) for defects, squared coefficient of distance variation (SCVD) for defects, defect cluster index (CIM), and the number of cluster groups (NCG) for defects by self-organized map (SOM) are utilized as inputs for GA–BPNN. Finally, a simulation case and a real-world case are used to confirm the effectiveness of proposed method. 相似文献
102.
One of the long-lasting challenges of the Architecture, Engineering and Construction (AEC) industry has been addressing personalised solutions as nearly affordable as possible to what could be offered by mass production in the post industrialisation era. Ever since its gestation, BIM has promised endless prospects for people, organisations, products and processes in the AEC industry. This paper sets out to investigate the benefits of BIM as a general configurator to facilitate customisation: offering personalised solutions at a price comparable to mass produced products and services. Providing a quick review of literature, the paper sets the scene for investigating how the generic capabilities of BIM applications can be utilised to offer customisable façade systems. Using a systemic approach, this is then used to elucidate future developments of the current project into next stages where other elements and parameters can be implanted into the basic family to broaden the choice and to reinforce this customisable façade solution. 相似文献
103.
Experimental results are presented concerning the zonal and total discharge distribution and characteristics in a compound channel cross-section comprising one rectangular main channel and two symmetrical floodplains. The discharges in the main channel, floodplains, and total compound channel are found to be highly correlated to several dimensionless parameters defined using the compound channel cross-section geometry. Multi-variable regression analysis was utilized for developing predictive models that can estimate the main channel, floodplains and total discharges as a function of four different dimensionless parameters. The developed models to predict the zonal and total discharges in compound channels are found to be highly significant according to several major statistics including the model standard error, coefficient of determination (R2), and F-statistic. The developed multi-variable regression-based models are also tested for validity using available experimental data. Several statistical tests applicable to the analysis of residuals have indicated the effectiveness of the developed predictive models. 相似文献
104.
《Microelectronics Reliability》2014,54(6-7):1066-1074
The Resilience Articulation Point (RAP) model aims at provisioning researchers and developers with a probabilistic fault abstraction and error propagation framework covering all hardware/software layers of a System on Chip. RAP assumes that physically induced faults at the technology or CMOS device layer will eventually manifest themselves as a single or multiple bit flip(s). When probabilistic error functions for specific fault origins are known at the bit or signal level, knowledge about the unit of design and its environment allow the transformation of the bit-related error functions into characteristic higher layer representations, such as error functions for data words, Finite State Machine (FSM) state, macro-interfaces or software variables. Thus, design concerns at higher abstraction layers can be investigated without the necessity to further consider the full details of lower levels of design. This paper introduces the ideas of RAP based on examples of radiation induced soft errors in SRAM cells, voltage variations and sequential CMOS logic. It shows by example how probabilistic bit flips are systematically abstracted and propagated towards higher abstraction levels up to the application software layer, and how RAP can be used to parameterize architecture-level resilience methods. 相似文献
105.
《Cities》2014
The redevelopment of vacant land is a contested issue in most urban places. Municipal governments advocate for the conversion of underutilized lots into tax-revenue generating developments, while residents may prefer additional green space or parks. The purpose of this paper is to provide a framework for managing these competing objectives through an analysis of vacant land redevelopment alternatives in Philadelphia, Pennsylvania. This study employs a GIS-based multi-objective land allocation (MOLA) methodology at two scales – citywide and neighborhood level – to balance three competing objectives: green space, commercial, and residential. The results of the multi-objective land allocation (MOLA) model identify the most suitable reuses of vacant land across Philadelphia. Further, this study provides a policy-oriented framework and methodology for balancing competing objectives in vacant land planning that could be readily applied in different contexts. 相似文献
106.
《材料与设计》2015
This present study investigates experimentally and numerically the crush response and energy absorption performances of auxetic foam-filled square tubes under quasi-static axial loading. Three different structures: empty, conventional and auxetic foam-filled square tubes have been compared and examined with respect to the deformation modes and load–displacement curves. Standard compression tests were conducted on the tubes to evaluate the influence of auxetic foam in the energy absorption of empty tubes. Moreover, results from computer simulation have also been supplemented to further examine the abovementioned effect. It is discovered that the auxetic foam-filled square tube is superior to empty and conventional foam-filled square tubes in terms of all studied crashworthiness indicators. 相似文献
107.
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109.
Leena E. Thomas 《Building Research & Information》2013,41(6):610-624
Existing buildings present the best opportunity for reducing greenhouse gas emissions in developed economies, given that only 2–3% of the building stock is newly built each year. Insights from a post-occupancy evaluation of a large-scale refurbishment project of a head office building in Sydney, Australia, are presented to inform future refurbishment strategies. The study evaluates occupant satisfaction and energy performance, and elicits influencing factors arising from the design process and interventions, ongoing building management, and operational performance. Occupants returned a high level of satisfaction across the range of environmental variables for overall comfort, temperature, lighting, and air quality as well as perceived productivity and health. These outcomes highlight the importance of improving indoor environmental quality for occupants particularly through increased fresh air, daylight, glare control, access to views, and noise management. The positive results reinforce the value of an integrated and user-responsive approach that was adopted for building design, development, and management. The reduction in operational energy (in this project, coupled with carbon reduction) as a consequence of refurbishment and positive user feedback demonstrates the potential to future-proof existing buildings in the context of climate change. Les bâtiments existants offrent la meilleure possibilité de réduction des émissions de gaz à effet de serre dans les économies développées, étant donné que les constructions neuves ne représentent chaque année que 2 à 3% du parc bâti. Les enseignements retirés d'une évaluation après occupation d'une opération de rénovation à grande échelle réalisée dans l'immeuble d'un siège social de Sydney, en Australie, sont présentés afin d'infléchir les futures stratégies en matière de rénovation. L'étude évalue la satisfaction des occupants et les performances énergétiques, et met au jour les facteurs d'influence qui découlent du processus de conception et des interventions réalisées, de la gestion en cours du bâtiment et des performances de fonctionnement. Les occupants ont exprimé un degré de satisfaction élevé sur l'ensemble des variables environnementales concernant le confort global, la température, l'éclairage et la qualité de l'air, aussi bien que la productivité et la santé telles qu'ils les ont perçues. Ces résultats mettent en évidence le fait qu'il est important d'améliorer la qualité environnementale intérieure pour les occupants, tout particulièrement en apportant davantage d'air frais et de lumière du jour, un plus grand contrôle de l'éblouissement, un accès accru à des panoramas et une gestion renforcée du bruit. Ces résultats positifs renforcent l'utilité d'une approche intégrée et sensible aux besoins des utilisateurs, telle qu'elle a été adoptée pour concevoir, aménager et gérer ce bâtiment. La réduction de l'énergie de fonctionnement (dans cette opération, conjointement avec la réduction du carbone) en conséquence de la rénovation et du feedback positif des utilisateurs démontre le potentiel de cette approche pour permettre aux bâtiments existants de bien affronter l'avenir dans le contexte du changement climatique. Mots clés: adaptation, changement climatique, confort, énergie, qualité environnementale intérieure, conception intégrée, occupants, évaluation après occupation, rénovation 相似文献
110.
通过对汶川地震公路隧道震害调查资料的统计分析,对隧道洞口结构进行了震害分析,结果表明:洞外结构受次生灾害影响较大,地震惯性力影响明显;硬岩洞口段隧道结构基本无破坏,软岩洞口段隧道结构震害较严重。通过三维有限差分数值模拟计算和现场典型震害分析,研究了公路隧道洞口结构的震害机理。探明了洞外结构震害机理,即洞外结构受次生灾害影响较大,震害的主要原因是地震惯性力,洞门墙结构和基础设计不合理以及隧道洞口所处位置也是影响洞外结构震害的重要因素。探明了洞口段隧道结构震害机理,即正穿坡面洞口段隧道结构存在软硬围岩交界面时,其附近软岩内隧道结构受较大强制位移作用;正穿坡面洞口段隧道结构覆盖层为软岩时,震害的主要因素是地震惯性力。研究成果对公路隧道洞口结构的抗减震技术有着重要的意义。 相似文献