基于灰色决策法的首采区位置优选

通过灰关联决策法,构造决策方案集,确定理想最优效果向量,并利用灰靶决策法求出各方案的效果向量与理想最优效果向量的靶心距,选择最优方案,进而确定合理的首采区位置。实例应用结果表明:灰色决策法简单易行,具有很大的实用价值。

Combining TOPSIS and GRA for supplier selection problem with interval numbers

Supplier selection can be regarded as a typical multiple attribute decision-making problem. In real-world situation, the values of the alternative attributes and their weights are always being nondeterministic, and as a result of this, the values are considered interval numbers. In addition, the common approach to measure the similarity between alternatives through their distance suffers from some minor shortcomings. To address these problems, this study develops a novel hybrid decision-making method by combining the technique for order preference by similarity to an ideal solution （TOPSIS） with grey relational analysis （GRA） for supplier selection with interval numbers. By introducing the intervals theory, the extensions of Euclidean distance and grey relational grade are defined. And then a new comprehensive closeness coefficient is constituted for supplier alternatives evaluation based on the interval Euclidean distance and the interval grey relational grade, which could indicate the distance-based similarity and the shape-based similarity simultaneously. A mtmerical example is taken to validate the flexibility of the proposed method, and result shows that this method can tackle the uncertainty in real-world supplier selection and also help decision makers to effectively select optimal suppliers.

Multi-attributed decision making for mining methods based on grey system and interval numbers

In the case of unknown weights, theories of multi-attributed decision making based on interval numbers and grey related analysis were used to optimize mining methods. As the representative of independence for the indicator, the smaller the correlation of indicators is, the greater the weight is. Hence, the weights of interval numbers of indicators were determined by using correlation coefficient. Relative closeness based on positive and negative ideal methods was calculated by introducing distance between interval numbers, which made decision making more rational and comprehensive. A new method of ranking interval numbers based on normal distribution was proposed for the optimization of mining methods, whose basic properties were discussed. Finally, the feasibility and effectiveness of this method were verified by theories and practice.

Optimal design of automotive body B-pillar using simplified finite element model of body-in-prime combined with an optimization procedure

Optimization of an automotive body structure faces the difficulty of having too many design variables and a too large design search space. A simplified model of body-in-prime(BIP) can solve this difficulty by reducing the number of design variables. In this study, to achieve lighter weight and higher stiffness, the simplified model of BIP was developed and combined with an optimization procedure;consequently, optimal designs of automotive body B-pillar were produced. B-pillar was divided into four quarters and each quarter was modelled by one simplified beam. In the optimization procedure, depth, width, and thickness of the simplified beams were considered as the design variables.Weight, bending and torsional stiffness were also considered as objective functions. The optimization procedure is composed of six stages: designing the experiments, calculating grey relational grade, calculating signal-to noise ratio,finding an optimum design using Taguchi grey relational analysis, performing sensitivity analysis using analysis of variance(ANOVA) and performing non-dominated sorting and multi-criteria decision making. The results show that the width of lower B-pillar has the highest effect(about 55%) and the obtained optimum design point could reduce the weight of B-pillar by about 40% without reducing the BIP stiffness by more than 1.47%.

Electroacupuncture at jiājǐ(夹脊 EX-B2) for lumbar intervertebral disc herniation:A randomized controlled trial

Objective： To compare the effect differences of electroacupuncture（EA） at Jiajǐ（夹脊 EX-B2） and conventional acupoints for lumbar intervertebral disc herniation（LIDH） and the factors influenced the effect during the way of data mining.Methods： A total of 160 patients of LIDH were randomly assigned into the EX-B2 group and the conventional acupoints group, 80 cases in each one. The patients in the EX-B2 group received EA at the symmetrical 2 acupoints of the bilateral EX-B2 on the lesion part. The patients in the conventional acupoints group received EA at the tender point of the lesion part, Zhibian（ 秩边BL54）, Huantiao（环跳 GB30）,weǐzhōng（委中BL40）, Chéngshān（承山BL57） and Fúyáng（跗阳BL59） on the affected side. The retain time of the needles is both 45 min. The treatment of the two groups is 3 times a week and for a connective 20 times. The modified Assessment Criteria for Low Lumbar Pain of Japanese Orthopedic Association（JOA）,Visual Analogue Scale（VAS） were evaluated before and after the treatment and at the 6-month follow up.Results：（1） Effective outcomes. JOA score： The JOA score of the patients in the EX-B2 group after treatment was（20.89 士 3.43）, and was（19.35 ±4.02） on the follow-up. Compared with the JOA score（12.35 ±4.42） in the same group before the treatment, there were statistical significant higher（both P0.05）. The JOA score in the EX-B2 group after treatment and on the follow-up were both higher than that of the conventional acupoints group at the same time point（both P0.05）. VAS score： The VAS score of the patients in the EX-B2 group on the 24 h after the first treatment was（4.09 ± 1.81）, and was（2.11 ± 1.30） after the treatment. Compared with the VAS score（4.09 ± 1.81） in the same group before the treatment, there were statistical significant lower（both P0.05）. The VAS score in the EX-B2 group on the 24 h after the first treatment and after treatment showed no statistical differences than that of the conventional acupoints group at the same time point（both P0.05）.（2）Related results from data mining： The middle-aged people and disease duration less than six months, their effect of the immediate treatment was the best. According to JOA score, EA at EX-B2 was better than EA conventional acupoints,either in the process of treatment effect, or in pertinence of the treatment, which were superior to EA conventional acupoints therapy; The best curative effect time of EA at EX-B2 was the first treatment after24 h, and the best curative effect of the conventional acupoints was after the first treatment. The age and disease duration also affected curative effect.Conclusion： The effect of EA at EX-B2 was superior to the conventional acupoints in treating LIDH.