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1.
针对传统低压回路电阻测试仪只能在被测设备停电时使用的一大限制,本文提出并设计了一种新型低压回路电阻测试仪。该仪器可在低压设备运行状态下对其回路电阻进行测量,在保证测量精度的前提下减少了设备停电率,大大提高了工作效率。 相似文献
2.
Some picture fuzzy Bonferroni mean operators with their application to multicriteria decision making
In this paper, we extend the Bonferroni mean (BM) operator with the picture fuzzy numbers (PFNs) to propose novel picture fuzzy aggregation operators and demonstrate their application to multicriteria decision making (MCDM). On the basis of the algebraic operational rules of PFNs and BM, we introduce some aggregation operators: the picture fuzzy Bonferroni mean, the picture fuzzy normalized weighted Bonferroni mean, and the picture fuzzy ordered weighted Bonferroni mean. Then, a new picture fuzzy MCDM method is proposed with the help of the proposed operators. Lastly, a practical application of proposed model is given to verify the developed model and related results of the proposed model is compared with the results of the existing models to indicate its applicability. 相似文献
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The paper focuses on the adaptive relational association rule mining problem. Relational association rules represent a particular type of association rules which describe frequent relations that occur between the features characterizing the instances within a data set. We aim at re-mining an object set, previously mined, when the feature set characterizing the objects increases. An adaptive relational association rule method, based on the discovery of interesting relational association rules, is proposed. This method, called ARARM (Adaptive Relational Association Rule Mining) adapts the set of rules that was established by mining the data before the feature set changed, preserving the completeness. We aim to reach the result more efficiently than running the mining algorithm again from scratch on the feature-extended object set. Experiments testing the method's performance on several case studies are also reported. The obtained results highlight the efficiency of the ARARM method and confirm the potential of our proposal. 相似文献
4.
Similarities and differences between male and female novice designers on color‐concept associations for warnings,action required,and signs and equipment status messages
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This research examined the male and female novice designers toward color associations for the concepts used for ‘warnings’, ‘action required’, and ‘signs and equipment status’ through a questionnaire‐based study. A total of 178 Hong Kong Chinese final year undergraduate design students (89 males and 89 females) participated in the study. The test used required the participants to indicate their choice of one of nine colors to associations with each of 38 concepts in a color‐concept table, so that any one color could be associated with any one of the concepts. For both male and female groups of novice designers, chi‐square tests revealed a strong color association for each concept tested in this study (P < .05). The results showed males and females agreed on some color‐concept association stereotypes which were therefore gender neutral. The male and female novice designers had the same color associations and similar levels of stereotype strengths for 21 concepts. The nine strongest and therefore most useful color‐concept association stereotypes for both male and female novice designers were: red‐danger, red‐fire, red‐hot, red‐stop, red‐emergency, red‐error, blue‐cold, blue‐male, and green‐exit. However, the male and female novice designers had different color association stereotypes for the standby (green vs. yellow), emergency exit (green vs. red), and toxic (purple vs. black) concepts, and the strengths of the 14 remaining associations for both groups were not at equivalent levels. Overall, it is anticipated that the findings of this study will act as a useful reference for novice designers and other design practitioners to optimize color coding in the design of ‘warnings’, ‘action required’, and ‘signs and equipment status’ messages. 相似文献
5.
Image enhancement algorithms are commonly used to increase the contrast and visual quality of low-dose x-ray images. This paper proposes an automated enhancement method using soft fuzzy sets with a new decision-making scheme based on Dempster-Shafer theory of evidence for the visual interpretation of pneumonia malformation in low-dose x-ray images, called as XEFSDS. The XEFSDS model first generates an original source x-ray image into a complementary image, then each original and complement image is applied to the characterized image object and background areas of fuzzy space. The S-function is utilized to define fuzzy soft sets for the classification of gray level ambiguity in both images, and hence a decision criterion via Dempster-Shafer approach and fuzzy interval has been adapted to discriminate uncertainties on the pixel intensity and the spatial information. Modified membership grade operations have been performed on each object/background area, and Werner’s AND/OR operator (an aggregation operator) has been utilized to build a new membership function from two modified membership functions. Finally, an enhanced image is obtained from the new membership function via defuzzification. Experiments on different pneumonia X-ray images demonstrate that the XEFSDS scheme produces better results than the existing methods. To show the advantages of the XEFSDS scheme, we have executed a segmentation based examination on enhanced image for the detection of pneumonia malformation as well as abnormal lobe (lobar pneumonia) or bronchopneumonia. 相似文献
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摘 要:主要介绍Sasol Agri公司硫酸四系统的技术改造,分两步进行,第一步更换转化器、热换热器及主省煤器,生产能力由1600t/d提高到1750 t/d,且鼓风机出口压力很低。第二步更换干燥塔、二吸塔及冷换热器,连续生产能力在1950 t/d以上。使用不锈钢材质及克瓦纳·凯密迪公司专有的换热器,使装置的改造相当成功,维护及操作费用较低,并具有较大的灵活性和可操作性。 相似文献
9.
中国大陆PCB产业自动化的现况与未来 总被引:1,自引:1,他引:0
从中国大陆PCB发展的现况分析实行设备自动化连线为企业所创造的价值。设备自动化连线是中国大陆PCB必须面临的改革出路。 相似文献
10.
K. Borer G. Czapek F. Hasenbalg M. Hauser S. Janos P. Loaiza U. Moser K. Pretzl C. Schütz P. Wicht S. Wüthrich 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2004,520(1-3):112-115
The ORPHEUS dark matter detector consists of 450 g superconducting tin granules with diameters of 28 and 36 μm. The detector has been operating in the shallow site of the underground laboratory in Bern (70 m.w.e). First preliminary results on WIMP detection sensitivity will be presented. 相似文献