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排序方式: 共有538条查询结果,搜索用时 15 毫秒
1.
Husain Syed Sameed Ong Eng-Jon Bober Miroslaw 《International Journal of Computer Vision》2021,129(5):1432-1450
International Journal of Computer Vision - We propose a novel CNN architecture called ACTNET for robust instance image retrieval from large-scale datasets. Our key innovation is a learnable... 相似文献
2.
Mitchell A. Lech M. Kokotoff D.M. Waterhouse R.B. 《Antennas and Propagation, IEEE Transactions on》2003,51(2):249-255
High-performance circular probe-fed stacked patch antenna designs are explored through the use of numerical optimization. New trends are sought to aid understanding and to suggest novel solutions. We describe the optimization technique, present a new design trend relating efficiency and bandwidth to the choice of substrate dielectric, and propose and demonstrate a novel, optimized antenna achieving 33% bandwidth whilst maintaining greater than 80% surface wave efficiency. 相似文献
3.
氢具有良好的可燃性,可用少量氢作为添加荆来改善天然气的自燃特性.通过试验,对比了天然气和汽油HCCI的性能,利用模拟的重整气验证了天然气加氢的效果,研究了天然气燃料重整实现在线产生氢的可行性,并进行了天然气在线燃料重整产生富氢重整气的闭环试验.试验结果表明,利用再循环的废气进行燃料重整产生富氢重整气是扩展HCCI工作范围和降低NOx排放的切实可行的有效方法. 相似文献
4.
The cognitive exhaustion model of helplessness (predicting withdrawal from constructive effortful processing after uncontrollability) was applied to decision making. After unsolvable problems (or no preexposure), Ss requested information from a matrix with 5 alternatives (films)?×?10 attributes and then chose the best film. Films in a set were either similar (difficult decision) or dissimilar (easy decision) in attractiveness. As predicted, Ss with an uncontrollable preexposure spent less time on predecisional information search, disregarded their own importance criteria when asking for information, and had attention highly focused on a selected option for the easy decision condition but diffused across options for the difficult decision condition. The implications of these findings for understanding cognitive mechanisms of learned helplessness and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Whey is an undurable product. treated very often as a waste which pollutes the natural environment. Whey which is a valuable source of protein, lactose, vitamins and mineral salts should be utilized completely. The present paper is a proposal of whey drying on porous carriers. It is proved experimentally that the proposed drying method guarantees good product quality. 相似文献
6.
Predicting weekly defect inflow in large software projects based on project planning and test status
Defects discovered during the testing phase in software projects need to be removed before the software is shipped to the customers. The removal of defects can constitute a significant amount of effort in a project and project managers are faced with a decision whether to continue development or shift some resources to cope with defect removal. The goal of this research is to improve the practice of project management by providing a method for predicting the number of defects reported into the defect database in the project. In this paper we present a method for predicting the number of defects reported into the defect database in a large software project on a weekly basis. The method is based on using project progress data, in particular the information about the test progress, to predict defect inflow in the next three coming weeks. The results show that the prediction accuracy of our models is up to 72% (mean magnitude of relative error for predictions of 1 week in advance is 28%) when used in ongoing large software projects. The method is intended to support project managers in more accurate adjusting resources in the project, since they are notified in advance about the potentially large effort needed to correct defects. 相似文献
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8.
Hector Archila Sebastian Kaminski David Trujillo Edwin Zea Escamilla Kent A. Harries 《Materials and Structures》2018,51(4):102
The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or round strips) has often been proposed as an alternative to relatively expensive reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost—bamboo is readily available in many tropical and sub-tropical locations, whereas steel reinforcement is relatively more expensive—and more recently, the drive to find more sustainable alternatives in the construction industry. This review addresses such ‘bamboo-reinforced concrete’ and assesses its structural and environmental performance as an alternative to steel reinforced concrete. A prototype three bay portal frame, that would not be uncommon in regions of the world where bamboo-reinforced concrete may be considered, is used to illustrate bamboo reinforced concrete design and as a basis for a life cycle assessment of the same. The authors conclude that, although bamboo is a material with extraordinary mechanical properties, its use in bamboo-reinforced concrete is an ill-considered concept, having significant durability, strength and stiffness issues, and does not meet the environmentally friendly credentials often attributed to it. 相似文献
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10.
Miroslaw Staron Wilhelm Meding Christer Nilsson 《Information and Software Technology》2009,51(4):721-737
As in every engineering discipline, metrics play an important role in software development, with the difference that almost all software projects need the customization of metrics used. In other engineering disciplines, the notion of a measurement system (i.e. a tool used to collect, calculate, and report quantitative data) is well known and defined, whereas it is not as widely used in software engineering. In this paper we present a framework for developing custom measurement systems and its industrial evaluation in a software development unit within Ericsson. The results include the framework for designing measurement systems and its evaluation in real life projects at the company. The results show that with the help of ISO/IEC standards, measurement systems can be effectively used in software industry and that the presented framework improves the way of working with metrics. This paper contributes with the presentation of how automation of metrics collection and processing can be successfully introduced into a large organization and shows the benefits of it: increased efficiency of metrics collection, increased adoption of metrics in the organization, independence from individuals and standardized nomenclature for metrics in the organization. 相似文献