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101.
102.
识别有故障倾向的模块能够将有限的资源最大化地用于软件维护.目的是利用软件模块排序模型预测模块故障倾向程度,从而指导纠正性软件维护.研究软件模块排序模型的评估和使用方法,并提出以贝叶斯信念网络改进排序模型的基本定量模型. 相似文献
103.
针尖增强拉曼光谱(TERS)技术由于其超高的空间分辨与灵敏的化学识别能力,在纳米尺度的结构表征和物理化学性质的分析中发挥着重要作用。本文首先回顾了高分辨TERS技术的近期发展与应用,并对高分辨成像的潜在物理机理进行了简要概述,接着介绍一种由超高分辨TERS成像衍生出来的新的分子化学结构解析方法―扫描拉曼埃分辨显微术(SRP),最后对SRP技术的进一步发展进行了展望。 相似文献
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Rafael Bernardo Carmona Benítez Rafael Bernardo Carmona Paredes Gabriel Lodewijks Joao Lemos Nabais 《Expert systems with applications》2013,40(12):4915-4921
This paper presents a modification of the Grey Model (GM) to forecast routes passenger demand growth in the air transportation industry. Forecast methods like Holt-Winters, autoregressive models, exponential smoothing, neural network, fuzzy logic, GM model calculate very high airlines routes pax growth. For this reason, a modification has been done to the GM model to damp trend calculations as time grows. The simulation results show that the modified GM model reduces the model exponential estimations grow. It allows the GM model to forecast reasonable routes passenger demand for long lead-times forecasts. It makes this model an option to calculate airlines routes pax flow when few data points are available.The United States domestic air transport market data are used to compare the performance of the GM model with the proposed model. 相似文献
106.
Ben Shneiderman Catherine Plaisant Rodrigo Botafogo Don Hopkins William Weiland 《New Review of Hypermedia and Multimedia》2013,19(2):101-117
Since browsing hypertext can present a formidable cognitive challenge, user interface design plays a major role in determining acceptability. In the Unix workstation version of Hyperties, a research-oriented prototype, we focussed on design features that facilitate browsing. We first give a general overview of Hyperties and its markup language. Customizable documents can be generated by the conditional text feature that enables dynamic and selective display of text and graphics. In addition we present: — an innovative solution to link identification: pop-out graphical buttons of arbitrary shape. — application of pie menus to permit low cognitive load actions that reduce the distraction of common actions, such as page turning or window selection. — multiple window selection strategies that reduce clutter and housekeeping effort. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and actions could be done rapidly, allowing users to concentrate on the contents. 相似文献
107.
Jane M. Watson Ben A. Kelly 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(2):145-166
Abstract: A task adapted from one used by Tversky and Kahneman (1971) was used in an interview or questionnaire context with 122 students from Grade 3 to Grade 13. Two questions assessed student understanding of the relationship of a sample to a population and of the expected value of the arithmetic mean, with and without information on a single value from the sample. Combining responses to the two questions, increasingly complex hierarchical sequences were identified in the observed responses in relation to the expected value of the means, an expectation variable, and in relation to the degree that ideas about variation were used to support judgements, a variation variable. Using data from another task performed by 68 of the students, responses were associated with the observed development of understanding of sampling more generally, a basic sampling variable. Overall, the associations of levels of response among the variables was not strong, suggesting more explicit discussion of sampling issues is required in classrooms. 相似文献
108.
We present a synchronized routing and scheduling problem that arises in the forest industry, as a variation of the log-truck scheduling problem. It combines routing and scheduling of trucks with specific constraints related to the Canadian forestry context. This problem includes aspects such as pick-up and delivery, multiple products, inventory stock, multiple supply points and multiple demand points. We developed a decomposition approach to solve the weekly problem in two phases. In the first phase we use a MIP solver to solve a tactical model that determines the destinations of full truckloads from forest areas to woodmills. In the second phase, we make use of two different methods to route and schedule the daily transportation of logs: the first one consists in using a constraint-based local search approach while the second one is a hybrid approach involving a constraint programming based model and a constraint-based local search model. These approaches have been implemented using COMET2.0. The method, was tested on two industrial cases from forest companies in Canada. 相似文献
109.
To get precise material data for advanced numerical modelling of tube hydroforming process, the tube bulging test is recommended. Stresses and strains in the tube cannot be evaluated easily and several approaches have been proposed. A review is proposed and points out their advantages and drawbacks. 相似文献
110.