Rong-Tsu Wang

Performance evaluation for airlines including the consideration of financial ratios

Most previous studies concerning airline performance evaluation focus merely on operational performance. Financial performance, however, which might directly influence the survival of an airline is usually ignored. The absence of financial ratios will directly lead to biased assessment. This paper tries to construct a performance evaluation process for airlines with financial ratios taken into consideration. First, a conceptual framework is redeveloped, based on the one created by Fielding et al. to help form performance indicators involving both transportation and finance aspects. Second, to overcome the problems of small sample size and unknown distribution of samples, the grey relation analysis is used to select the representative indicators and the TOPSIS method is used for the outranking of airlines. Third, the organizational characteristics of an airline are used to divide the total performance into three major departments of an airline: production, marketing, and management. The division of total performance is helpful for operators to recognize the performance of a department of an airline and to identify the responsibility of a department. Finally, a case study is conducted using the example of Taiwans five major airlines. The empirical result shows that performance evaluation for airlines can be more comprehensive, if financial ratios are considered.

A numerical solution method to interval quadratic programming

Quadratic programming has been widely applied to solving real world problems. The conventional quadratic programming model requires the parameters to be known constants. In the real world, however, the parameters are seldom known exactly and have to be estimated. This paper discusses the interval quadratic programming problems where the cost coefficients, constraint coefficients, and right-hand sides, are represented by interval data. Since the parameters are interval-valued, the objective value is interval-valued as well. A pair of two-level mathematical programs is formulated to calculate the upper bound and lower bound of the objective values of the interval quadratic program. Based on the duality theorem and by applying the variable transformation technique, the pair of two-level mathematical programs is transformed into conventional one-level quadratic program. Solving the pair of quadratic programs produces the interval of the objective values of the problem. An example illustrates the whole idea and sheds some light on interval quadratic programming.

Measuring production and marketing efficiency using grey relation analysis and data envelopment analysis

The aim of this paper is to measure production and marketing efficiencies in the printed circuit board (PCB) industry using grey relation analysis (GRA) and data envelopment analysis (DEA) techniques. A total of 32 efficiency indicators are initially considered and seven are selected. They represent five indicators for production efficiency and two for marketing efficiency. Fifteen of the 23 companies evaluated need improvement in both production and marketing efficiencies, while four companies had their priority production efficiency improvement and the remaining four companies with priority in marketing efficiency improvement.

Efficiency measures of PCB manufacturing firms using relational two-stage data envelopment analysis

Taiwan is currently the fourth largest contributor to the printed circuit board (PCB) industry. In exploring the operation activities of PCB industry, most studies focuses primarily on manufacturing or production technologies. In this paper, we evaluate the performance of PCB manufacturing firms in Taiwan. Since the whole production process of the manufacturing firms can be divided into two sub-processes: production acquisition and profit earning, this study employs the relational two-stage DEA approach, which takes into account the series relationship of the two sub-processes within the whole process, to decompose and measure the efficiencies of the manufacturing firms. It is found that none of the manufacturing firms perform efficiently both in the stage of production acquisition and the stage of profit earning. In addition, the low efficiency score of the whole production process is mainly due to the low efficiency score of the profit generating process. To improve productivity and profitability, the manufacturing firms need to consider the issues of product improvements and technological innovation in the future.

Program for Rapid Computation of the Thermal Performance of a Heat Sink with Embedded Heat Pipes

This article uses Visual Basic commercial software to develop a Windows program for rapidly calculating the thermal performance of a heat sink with embedded heat pipes. A heat sink with embedded heat pipes transfers the total heat capacity from the heat source to the base plate with embedded heat pipes and fins sequentially, and then dissipates the heat flow into the surrounding air. The computing core of this Windows program employs the theoretical thermal resistance analytical approach with iterative convergence, as stated in this article, to obtain a numerical solution. The results show that the estimation error between the numerical and experimental solutions is less than 5%. From this Windows program, the optimum height of the embedded heat pipes inserted through fins is 21mm and 15mm for one pair and two pairs of embedded heat pipes, respectively.

The Application of Goal Programming to the Scheduling Problem of the Professional Baseball League

In professional baseball sport, game scheduling is one of the most important routine jobs for a sporting league. The quality of annual game schedule directly affects the income of ticket sales and the operational costs of baseball teams. In Taiwan, the most commonly used ”host and guest” scheduling principle in professional sports is not applicable, because the most profitable ticket sales concentrate on some metropolitan areas and the fans do not have obvious geographical preferences. For this reason, the game schedule of professional baseball league in Taiwan is mostly determined according to ticket sales as the major factor, to equitability between teams, and to equitability between different areas or cities. Therefore the scheduling models developed in other countries cannot be applied in the game schedule of Taiwan professional baseball league. This study develops a game scheduling model for Taiwan professional baseball league based on goal programming technique. Real data from Taiwan professional baseball games have been used to test the performance of the proposed model. The test shows that the proposed model is effective and efficient.

Performance evaluation of Taiwan's TFT-LCD industry

This study combines Grey Relation Analysis (GRA) and Data Envelopment Analysis (DEA) to provide the flat panel industry with an evaluation model for handling input/output in the Thin Film Transistor Liquid Crystal Display (TFT-LCD) industry. This study takes Taiwans Big Five flat panel display companies - AUO, CMO, CPT, HannStar and QDI - as subjects of research. The results show that AUO2004 and CMO2004, whether in production efficiency or marketing effectiveness, were all correspondingly effective. It so happened that these two companies in 2004 were third and fourth in market share in the TFT-LCD world market, conforming to the business benchmark for Taiwans TFT-LCD industry.

Using grey relation analysis and TOPSIS to measure PCB manufacturing firms efficiency in Taiwan

This paper tries to construct a performance evaluation procedure for printed circuit board (PCB) industry combining productivity and financial ratios. A case study is conducted using 22 PCB companies in Taiwan as example. A total of 51 indicators are initially considered and fourteen are selected. They represent five indicators for production efficiency, four for marketing efficiency, and five for execution efficiency. The division of total performance is helpful for operators to recognize the performance of a department of a PCB firm and to identify the responsibility of that department.