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141.
提出了一种基于粗糙集的不完备测试数据填补方法。该方法首先利用粗糙集中下近似集的性质对随机生成的测试数据进行填补,然后根据属性数据的取值概率函数求出的结果进行二次填补,从而完成对不完备测试数据的完备化处理,生成最优测试用例。采用本方法可以较好地反映待测系统所蕴含的规则,且可以避免测试数据的冲突。 相似文献
142.
氯化聚乙烯作为一种新型的高分子材料,被广泛地应用于塑料和橡胶的生产中。反应釜温度是其过程控制的主要被控参数,但是由于其存在纯滞后和大惯性等特点,普通的串级控制方式很难得到良好的控制效果。本文基于灰色模型的原理,设计了灰色PID控制器。仿真表明,该控制器具有良好的抗干扰性和稳定的鲁棒性,可有效改善系统的控制效果。 相似文献
143.
144.
A. Giumlia-Mair B. Gilmour L. Stefan N. Degasperi P. Bellintani 《Materials and Manufacturing Processes》2017,32(7-8):850-856
ABSTRACTThe workshop of Zambana el Vato (region Trentino, Northern Italy), is dated to the period between the 7th-6th and the 5th century BC. Iron working activities are clearly recognizable from the various finds. Among them there are working slag, heated clay, fragments of hearth or forge, hammerscale and more residues that can be referred to iron technology. A number of selected specimens were sectioned and mounted for photomicroscopy to identify the structure and some of the mounted samples were also examined by scanning electron microscopy (SEM) using both a back scattered electron detector and energy dispersive (EDS) x-ray analysis. This paper presents the results of these studies. The hearths were regularly repaired, as their fragments were found mixed with working slag. The hammerscale samples indicate that there were three iron-working areas. The fragments of forge with traces of tuyeres indicate that bellows were employed. Refining slag was identified among the debris. This is particularly significant as for the moment no iron refining centers are known in this area. 相似文献
145.
James J.H. Liou Jolanta Tamošaitienė Edmundas K. Zavadskas Gwo-Hshiung Tzeng 《国际生产研究杂志》2016,54(1):114-134
Greening the supply chain is an increasingly important concern for many business enterprises and a challenge for logistics management. Critical functions within green supply chain management are internal improvements and selection of green suppliers. This study proposes a novel, hybrid model that addresses dependent relationships between various criteria and the vague information coming from decision-makers. The Decision-making Trial and Evaluation Laboratory (DEMATEL) technique structures the relationships among criteria, thereby constructing an influential network relationship map (INRM). Meanwhile the DEMATEL-based, analytical network process (ANP) method aids in obtaining influential weights of the criteria. Decision-makers may hold diverse opinions and preferences due to incomplete information, differences in knowledge or simply conflicts that are inherent between various departments. This can make it difficult to judge the performance of alternatives. One remedy is to apply a modified COmplex PRoportional ASsessment of alternatives with Grey relations. Next, this is applied to improve each criterion for integration of the performance values obtained in closing the aspiration level from different expert opinions based on INRM. An empirical example using data from a Taiwanese electronics company is provided to demonstrate our proposed method. The results can provide firms with a knowledge-based understanding of the source of some problems, thus reducing the performance gaps and closing the aspiration levels. Finally, there is a discussion on certain managerial implications. 相似文献
146.
Chilled cast iron tappet has a tendency microstructure of white, mottled and gray iron. The exact composition and other casting parameters, like pouring temperature, inoculation and coating, need to be determined for achieving the desired thickness of the chilled layer. Chilled cast iron finds applications in areas where improved hardness and wear resistance are required. Mottled cast iron has very poor machinability and high brittleness due to the presence of secondary cementite. These constitute the limitations for its use. The influence of inoculation, pouring temperature, coating thickness and chill plate on chilled depth was investigated. Taguchi design-of-experiments (DOE) are used for generating an optimal set of casting parameters to obtain a satisfactory chilled depth. Analysis of the effects of all the parameters on chilled depth has been carried out through a microstructure study. 相似文献
147.
148.
基于最大隶属度的区间概率灰色随机多准则决策方法 总被引:2,自引:0,他引:2
定义了一种灰色隶属函数.针对概率为区间数、准则值为区间灰数的灰色随机多准则决策问题,提出一种基于最大隶属度的决策方法.首先,运用区间数可能度排序向量将区间概率转化为点概率,并将其转化为无风险决策问题;然后,计算各方案在负理想方案到正理想方案上的灰色隶属度,并计算各方案准则值的相对灰度,进而根据灰色隶属度和相对灰度大小对方案进行排序;最后,通过算例验证了该方法的可行性和有效性. 相似文献
149.
Daniela PatrascuAuthor VitaeIulia DavidAuthor Vitae Vasile DavidAuthor VitaeConstantin MihailciucAuthor Vitae Ioan StamatinAuthor VitaeJean CiureaAuthor Vitae Livia NagyAuthor VitaeGéza NagyAuthor Vitae Anton Alexandru CiucuAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):731-736
Iron(II) phthalocyanine (FePc) modified multi-wall carbon nanotubes paste electrodes (MWCNTPEs) were used as voltammetric sensors to selectively detect dopamine (DA) in the presence of serotonin (5-HT). The electrochemical behavior of DA at the new modified electrode was investigated using CV. The enhanced current response of DA indicates that FePc modification of the MWCNTPE surface results in a high catalytic activity for the redox reaction of DA. Differential pulse voltammetry was applied in detection of DA and 5-HT at FePc-MWCNTPE. The method parameters were optimized. Detection limit of 2.05 × 10−7 M was obtained for DA by using the electrocatalytic oxidation signal corresponding to the FeII/FeIII redox process. The separation between the peak potentials of DA and 5-HT is 170 mV which is large enough for the simultaneously, selective determination of the two chemical species in their mixtures. There was no electrochemical response for ascorbic acid (AA) added in the sample. The monoamine neurotransmitter measuring method has been tested in analyzing deproteinized serum samples. 相似文献
150.
Ney Sodr Pablo Guillermo Gonzales-Ormeo Helena Maria Petrilli Cludio Geraldo Schn 《Calphad》2009,33(3):576-583
The metastable phase diagram of the BCC-based ordering equilibria in the Fe–Al–Mo system has been calculated via a truncated cluster expansion, through the combination of Full-Potential-Linear augmented Plane Wave (FP-LAPW) electronic structure calculations and of Cluster Variation Method (CVM) thermodynamic calculations in the irregular tetrahedron approximation. Four isothermal sections at 1750 K, 2000 K, 2250 K and 2500 K are calculated and correlated with recently published experimental data on the system. The results confirm that the critical temperature for the order–disorder equilibrium between Fe3Al–D03 and FeAl–B2 is increased by Mo additions, while the critical temperature for the FeAl–B2/A2 equilibrium is kept approximately invariant with increasing Mo contents. The stabilization of the Al-rich A2 phase in equilibrium with overstoichiometric B2–(Fe,Mo)Al is also consistent with the attribution of the A2 structure to the τ2 phase, stable at high temperatures in overstoichiometric B2–FeAl. 相似文献