基于组合赋权-TOPSIS模型的机场运行效率评价

为提高机场运行效率评价结果的科学性和全面性,提出了一种基于组合赋权-TOPSIS(technique for order performance by similarity to ideal solution)模型的机场运行效率评价方法。从机位运行效率、旅客登机效率、飞机滑行效率和协同效率4个维度出发,构建了由航班靠桥率、廊桥周转率、机位变更比例等11个指标组成的机场运行效率评价体系;利用G1法、熵权法分别计算评价指标主观和客观权重,以最小化主客观加权属性偏离程度为目标计算组合权重;使用TOPSIS计算待评价机场综合评价指数。利用该模型分析国内3类共8家机场的运行效率,可以得到各评价对象的运行效率等级和综合排名。结果表明:该模型能够有效探明影响机场运行效率的主要因素,具有一定的参考价值。

Extension of TOPSIS for fuzzy multi-attribute decision making problem based on experimental analysis

This paper is concerned with a technique for order performance by similarity to ideal solution（TOPSIS） method for fuzzy multi-attribute decision making,in which the information about attribute weights is partly known and the attribute values take form of triangular fuzzy numbers.Considering the fact that the triangular fuzzy TOPSIS results yielded by different distance measures are different from others,a comparative analysis of triangular fuzzy TOPSIS ranking from each distance measure is illustrated with discussion on standard deviation.By applying the most reasonable distance,the deviation degrees between attribute values are measured.A linear programming model based on the maximal deviation of weighted attribute values is established to obtain the attribute weights.Therefore,alternatives are ranked by using TOPSIS method.Finally,a numerical example is given to show the feasibility and effectiveness of the method.

TOPSIS with Belief Structure for Group Belief Multiple Criteria Decision Making

The technique for order performance by similarity to ideal solution （TOPSIS） is one of the major techniques in dealing with multiple criteria decision making （MCDM） problems, and the belief structure （BS） model has been used successfully for uncertain MCDM with incompleteness, impreciseness or ignorance. In this paper, the TOPSIS method with BS model is proposed to solve group belief MCDM problems. Firstly, the group belief MCDM problem is structured as a belief decision matrix in which the judgments of each decision maker are described as BS models, and then the evidential reasoning approach is used for aggregating the multiple decision makers＇ judgments. Subsequently, the positive and negative ideal belief solutions are defined with the principle of TOPSIS. To measure the separation from ideal solutions, the concept and algorithm of belief distance measure are defined, which can be used for comparing the difference between BS models. Finally, the relative closeness and ranking index are calculated for ranking the alternatives. A numerical example is given to illustrate the proposed method.

Performance comparison of power fading mitigation techniques in multiband OFDM-UWB signals transmission along LR-PONs

The single sideband （SSB） modulation is assessed as a means to mitigate the dispersion-induced power fading on the distribution of ortogonal frequency division multiplexing （OFDM） ultra wideband （UWB） radio signals along long-reach passive optical networks （LR-PONs）. Particularly, two different SSB ar- chitectures, namely, Sieben＇s architecture and four phase modulator （FPM） architecture are optimized to provide maximum sideband suppression. The minimum optical signal-to-noise ratio （OSNR） required to simultaneously distribute all the 14 OFDM-UWB sub-bands along the LR-PON distances ranging between 80 and 100 km is also evaluated through numerical simulation. FPM architecture is preferable over Sieben＇s architecture because the latter SSB architecture generates carriers-carriers beat term at the photodetector output with high power, thereby causing significant degradation in the OFDM-UWB sub-bands with lower central frequencies. The simultaneous distribution of the 14 SSB OFDM-UWB sub-bands in the LR-PON using the FPM architecture shows a minimum OSNR penalty of 3 dB compared with the centralized dis- persion compensation technique.

Penetration performance of W/Cu double-layer shaped charge liners

Two kinds of W/Cu double-layer shaped charge liner（SCL） were prepared by chemical vapor deposition（CVD） combined with electroforming technique： A SCL with W inner layer and Cu outer layer, B SCL with Cu inner layer and W outer layer. The penetration properties of A and B SCLs were researched. The results show that the two SCLs can form continuous jet and the tip velocities of A and B jets are 7.4 and 6.3 km s^（-1）, respectively. The kinetic energy density（5.3 9 1011 J m-3） of A jet tip increases by 194.4 %compared with that（1.8 9 1011 J m-3） of B jet tip. B jet,however, exhibits deeper penetration depth at the same experimental conditions. The chemical component and microstructure of the area nearby the ballistic perforation were researched. Component analysis shows that both the jets are formed only from inner layer metal. Microstructure analysis shows that martensite and intermetallic form around ballistic perforation penetrated by A SCL due to the intensive interaction between W jet and steel target. The two kinds of newly formed ultrahard phases also hinder the jet from penetrating target further. As a result of relatively alleviative interaction between Cu jet and target, only solid solution rather than ultrahard phases forms around ballistic perforation penetrated by B SCL.