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According to previous studies, the workforce competencies of engineers in manufacturing industries generally comprise technical, generic, and knowledge competencies. However, these categories of workforce competencies are insufficient for firms whose manufacturing processes are very easily interrupted by anomalies and whose core competency is highly related to production yield. In addition to drawing attention to the importance of identifying engineers’ problem-solving competencies, this article proposes a procedure to identify and rate workforce competencies for firms in the manufacturing industry. An IC packaging process engineer was used as an example to illustrate the proposed competency identification and rating procedure. In contrast to previous studies, this article suggests that problem-solving competencies can be identified from engineers’ responses to the anomalies commonly encountered in each step of the manufacturing process and that operational competency can be identified from the knowledge, techniques, or capabilities required to fulfill a task in each step of the manufacturing process. For the IC packaging and testing industry, this article can help human resources not only evaluate the competency of job candidates but also design training courses according to the job tenure of engineers. Furthermore, this article results can be used to design teaching material for apprenticeship to help engineers develop competencies in a structured manner and enhance their sensitivities to production-line problems.

Cardiovascular diseases have been identified as one of the top three causes of death worldwide, with onset and deaths mostly due to heart failure (HF). In ICU, where patients with HF are at increased risk of death and consume significant medical resources, early and accurate prediction of the time of death for patients at high risk of death would enable them to receive appropriate and timely medical care. The data for this study were obtained from the MIMIC-III database, where we collected vital signs and tests for 6699 HF patient during the first 24 h of their first ICU admission. In order to predict the mortality of HF patients in ICUs more precisely, an integrated stacking model is proposed and applied in this paper. In the first stage of dataset classification, the datasets were subjected to first-level classifiers using RF, SVC, KNN, LGBM, Bagging, and Adaboost. Then, the fusion of these six classifier decisions was used to construct and optimize the stacked set of second-level classifiers. The results indicate that our model obtained an accuracy of 95.25% and AUROC of 82.55% in predicting the mortality rate of HF patients, which demonstrates the outstanding capability and efficiency of our method. In addition, the results of this study also revealed that platelets, glucose, and blood urea nitrogen were the clinical features that had the greatest impact on model prediction. The results of this analysis not only improve the understanding of patients’ conditions by healthcare professionals but allow for a more optimal use of healthcare resources.

Although many scoring models have been developed in literature to oer nancial institutions guidance in credit granting decision, the pur- pose of most scoring models are to improve their discrimination ability, not their explanatory ability. Therefore, the conventional scoring models can only provide limited information in the relationship among customer de- mographics, default risk, and credit card attributes, such as APR (annual percentage rate) and credit limits. In this paper, a Bayesian behavior scor- ing model is proposed to help nancial institutions identify factors which truly reect customer value and can aect default risk. To illustrate the proposed model, we applied it to the credit cardholder database provided by one major bank in Taiwan. The empirical results show that increasing APR will raise the default probability greatly. Single cardholders are less accountable for credit card repayment. High income, female, or cardholders with higher education are more likely to have good repayment ability.

The integration of statistical process control and engineering process control has been reported as an effective way to monitor and control the autocorrelated process. However, because engineering process control compensates for the effects of underlying disturbances, the disturbance patterns become very hard to recognize, especially when various abnormal control chart patterns are mixed and co-existed in the engineering process. In this study, a new control chart pattern recognition model which integrates multivariate adaptive regression splines and recurrent neural network is proposed to not only address the problem of feature selection (i.e., lagged process measurements) but also improve the pattern recognition accuracy. The performance of the proposed method is evaluated by comparing the recognition results of multivariate adaptive regression splines and recurrent neural network with the results of four competing approaches (multivariate adaptive regression splines-extreme learning machine, multivariate adaptive regression splines-random forest, single recurrent neural network, and single random forest) on the simulated individual process data. The experimental study shows that the proposed multivariate adaptive regression splines and recurrent neural network approach can not only solve the problem of variable selection but also outperform other competing models. Moreover, according to the lagged process measurements selected by the proposed approach, lagged observations that exerted significant impact on the construction of the control chart pattern recognition model can be identified successfully. This study has significant implications for research and practice in production management and provides a valuable reference for manufacturing process managers to better understand and develop strategies for control chart pattern recognition.

An ICU is a critical care unit that provides advanced medical support and continuous monitoring for patients with severe illnesses or injuries. Predicting the mortality rate of ICU patients can not only improve patient outcomes, but also optimize resource allocation. Many studies have attempted to create scoring systems and models that predict the mortality of ICU patients using large amounts of structured clinical data. However, unstructured clinical data recorded during patient admission, such as notes made by physicians, is often overlooked. This study used the MIMIC-III database to predict mortality in ICU patients. In the first part of the study, only eight structured variables were used, including the six basic vital signs, the GCS, and the patient’s age at admission. In the second part, unstructured predictor variables were extracted from the initial diagnosis made by physicians when the patients were admitted to the hospital and analyzed using Latent Dirichlet Allocation techniques. The structured and unstructured data were combined using machine learning methods to create a mortality risk prediction model for ICU patients. The results showed that combining structured and unstructured data improved the accuracy of the prediction of clinical outcomes in ICU patients over time. The model achieved an AUROC of 0.88, indicating accurate prediction of patient vital status. Additionally, the model was able to predict patient clinical outcomes over time, successfully identifying important variables. This study demonstrated that a small number of easily collectible structured variables, combined with unstructured data and analyzed using LDA topic modeling, can significantly improve the predictive performance of a mortality risk prediction model for ICU patients. These results suggest that initial clinical observations and diagnoses of ICU patients contain valuable information that can aid ICU medical and nursing staff in making important clinical decisions.

It is known that Data Envelopment Analysis (DEA) does not perform full ranking because DEA only classifies all of the efficient units as one in the Pareto sense. In this research, a hybrid approach, VFAD, that integrates the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) methodology with Fuzzy Analytic Hierarchy Process (FAHP) and DEA is proposed to overcome this problem. Data collected from 50 fast food chain stores in Taipei City was used to verify the performance of the proposed VFAD approach. The result shows that the rank order of overall efficiency (OE) estimated by the DEA method alone and by VFAD approach are strongly and positively correlated. Moreover, the proposed VFAD method can fully rank the alternatives with multiple inputs and outputs. Thus, our empirical results conclude that some chain stores with equal efficiency in the Pareto sense can be more successfully ranked by our new ranking mechanism. Our proposed VFAD approach results in better performance in full ranking than the DEA method alone.

Sales forecasting has long been crucial for companies since it is important for financial planning, inventory management, marketing, and customer service. In this study, a novel clustering-based sales forecasting scheme that uses an extreme learning machine (ELM) and assembles the results of linkage methods is proposed. The proposed scheme first uses the K-means algorithm to divide the training sales data into multiple disjointed clusters. Then, for each cluster, the ELM is applied to construct a forecasting model. Finally, a test datum is assigned to the most suitable cluster identified according to the result of combining five linkage methods. The constructed ELM model corresponding to the identified cluster is utilized to perform the final prediction. Two real sales datasets of computer servers collected from two multinational electronics companies are used to illustrate the proposed model. Empirical results showed that the proposed clustering-based sales forecasting scheme statistically outperforms eight benchmark models, and hence demonstrates that the proposed approach is an effective alternative for sales forecasting.

Recognition of unnatural control chart patterns (CCPs) is an important issue because the unnatural CCPs can be associated with specific assignable causes negatively affecting the manufacturing process. By assuming that an unnatural CCP is a combination of normal pattern and process disturbance, a multi-stage control chart pattern recognition scheme which integrates independent component analysis (ICA) and support vector machine (SVM) is proposed in this study. The proposed multi-stage ICA-SVM scheme first uses ICA to extract independent components (ICs) from the monitoring process data containing CCPs. The normal pattern and process disturbance hidden in the process data can be discovered in the ICs. Then, the IC representing the process disturbance can be identified. Finally, the identified IC and the data of the monitoring process are used as input variables to develop three different SVM models for CCP recognition. The simulation results show that the proposed multi-stage ICA-SVM scheme not only produces accurate and stable recognition results but also has better classification accuracy than four competing models.

This paper combines two multicriteria decision-making (MCDM) tools to identify the critical success factors (CSFs) that impact the performance of personnel training course projects in the semiconductor industry in Taiwan. The study collected the factors that influence performance by interviewing experts and constructed a hierarchical factor table. The fuzzy analytic hierarchy process was used to determine the weight of each factor, and the acceptance advantage concept of VlseKriterijumska Optimizacija I Kompromisno Resenje was used to objectively identify the CSFs. The study found four CSFs that affect project performance and proposed five practical implications. This paper verified that combining two MCDM tools can help training institutions to allocate their resources appropriately by focusing on the CSFs, identified by their weights, and thus, promote their training courses at lower cost and with greater efficiency. Copyright © 2013 John Wiley & Sons, Ltd.

Forecasting stock prices is a major activity of financial firms and private investors when they make investment decisions. Feature extraction is usually the first step of a stock price forecasting model development. Wavelet transform, used mainly for the extraction of information contained in signals, is a signal processing technique that can simultaneously analyze the time domain and the frequency domain. When wavelet transform is employed to construct a forecasting model, the wavelet basis functions and decomposition stages need to be determined first. However, because forecasting models constructed by different wavelet sub-series would exhibit different forecasting capabilities and yield varying forecast results, the selection of wavelet that can lead to an optimal forecast outcome is extremely critical in model construction. In this study, a new stock price forecasting model which integrates wavelet transform, multivariate adaptive regression splines (MARS), and support vector regression (SVR) (called Wavelet-MARS-SVR) is proposed to not only address the problem of wavelet sub-series selection but also improve the forecast accuracy. The performance of the proposed method is evaluated by comparing the forecasting results of Wavelet-MARS-SVR with the ones made by other five competing approaches (Wavelet-SVR, Wavelet-MARS, single ARIMA, single SVR and single ANFIS) on the stock price data of two newly emerging stock markets and two mature stock markets. The empirical study shows that the proposed approach can not only solve the problem of wavelet sub-series selection but also outperform other competing models. Moreover, according to the sub-series which are selected by the proposed approach, we can successfully identify the data of which sessions (or points in time) among past stock market prices exerted significant impact on the construction of the forecasting model.

Forecasting stock prices is a major activity of financial firms and private investors. In developing a stock price forecasting model, the first step is usually feature extraction. Nonlinear independent component analysis (NLICA), a novel feature extraction technique that assumes the observed mixtures are non-linear combinations of latent source signals, is used to find independent sources when observed data are mixtures of unknown sources, and prior knowledge of the mixing mechanisms is not available. In this paper, a stock price forecasting model which first uses NLICA as preprocessing to extract features from forecasting variables is developed. Then the features, called independent components (ICs), serve as the inputs of support vector regression (SVR) to build the forecasting model. The advantage of the proposed methodology is that the information hidden in the original data can be discovered by feature extraction. Therefore, NLICA can provide more valuable information for financial forecasting. Two datasets of major Asian stock markets-China and Japan, Shanghai Stock Exchange Composite (SSEC) and Nikkei 225 stock indexes, are used as illustrative examples. For comparison, the integration of traditional principal component analysis (PCA) with SVR (called PCA-SVR), linear ICA with SVR (called LICA-SVR) and single SVR approaches were applied to evaluate the prediction accuracy of the proposed approach. Empirical results show that the proposed method (NLICA-SVR) not only improves the prediction accuracy of the SVR approach but also outperforms the PCA-SVR, LICA-SVR and single SVR methods.

A Bayesian latent variable model with classification and regression tree approach is built to overcome three challenges encountered by a bank in credit-granting process. These three challenges include (1) the bank wants to predict the future performance of an applicant accurately; (2) given current information about cardholders' credit usage and repayment behavior, financial institutions would like to determine the optimal credit limit and APR for an applicant; and (3) the bank would like to improve its efficiency by automating the process of credit-granting decisions. Data from a leading bank in Taiwan is used to illustrate the combined approach. The data set consists of each credit card holder's credit usage and repayment data, demographic information, and credit report. Empirical study shows that the demographic variables used in most credit scoring models have little explanatory ability with regard to a cardholder's credit usage and repayment behavior. A cardholder's credit history provides the most important information in credit scoring. The continuous latent customer quality from the Bayesian latent variable model allows considerable latitude for producing finer rules for credit granting decisions. Compared to the performance of discriminant analysis, logistic regression, neural network, multivariate adaptive regression splines (MARS) and support vector machine (SVM), the proposed model has a 92.9% accuracy rate in predicting customer types, is less impacted by prior probabilities, and has a significantly low Type I errors in comparison with the other five approaches.

Despite the fact that Taiwan’s high-tech industry has gradually secured a leading position in the world, enterprises in Taiwan have striven to strengthen their technical advancement by providing employees with various internal or external training programmes. These institutional training programmes are designed to sustain competitive advantage, enhance the quality of manpower and improve operational efficiency. Much literature assesses the efficiency of an internal training programme that is initiated by a firm, but only a little literature studies the efficiency of an external training programme that is led by a government. Various efficiency measurement tools, such as conventional statistical methods and non-parametric methods, have been successfully developed in the literature. Among these tools, the data envelopment analysis (DEA) approach is one of the most widely discussed. However, the DEA's capability to discriminate efficient decision-making units from inefficient decision-making units requires much improvement (Adler and Yazhemsky). In this paper, a two-stage approach of integrating spatiotemporal independent component analysis (stICA) and DEA is developed for efficiency measurement. stICA is used to search for latent source signals where no relevant signal mixture mechanisms are available; and DEA is used to measure the relative efficiencies of decision-making units (DMUs). We suggest using stICA first to extract the input variables for generating independent components (IC), then selecting the ICs representing the independent sources of input variables, and finally inputting the selected ICs as new variables in the DEA model. To find the effects of environmental variables on the estimated efficiency scores, the Tobit–Bayes (censored) regression is applied. A simulated dataset and the training institution dataset provided by the Semiconductor Institute in Taiwan is used for analysis. The empirical result shows that the proposed method can not only separate performance differences between the training institutions but also improve the discriminatory capability of the DEA's efficiency measurement. The study results can serve as a reference for training institutions wishing to enhance their training efficiency.

A back-propagation neural network with the output provided by a rule-based expert system is designed for short-term power load forecasting. To demonstrate that the inclusion of the prediction from a rule-based expert system of a power system would improve the predictive capability of the network, load forecasting is performed on the Taiwan power system. The hourly load for one typical day was evaluated and, in that case, the inclusion of the rule-based expert system prediction significantly improved the neural network's prediction of power load. Moreover, the proposed combined approach converges much faster than the conventional neural network and the rule-based expert system method. Extensive studies were performed on the robustness of the built network model by using different specified censoring time. The prediction intervals of future power load series are also provided, to evaluate the prediction efficiency of the neural network model.

With the rapid technology development and improvement, the product failure time prediction becomes an even harder task because only few failures in the product life tests are recorded. The classical statistical model relies on the asymptotic theory and cannot guarantee that the estimator has the finite sample property. To solve this problem, we apply the hierarchical Bayesian neural network (HBNN) approach to predict the failure time and utilize the Gibbs sampler of Markov chain Monte Carlo (MCMC) to estimate model parameters. In this proposed method, the hierarchical structure is specified to study the heterogeneity among products. Engineers can use the heterogeneity estimates to identify the causes of the quality differences and further enhance the product quality. In order to demonstrate the effectiveness of the proposed hierarchical Bayesian neural network model, the prediction performance of the proposed model is evaluated using multiple performance measurement criteria. Sensitivity analysis of the proposed model is also conducted using different number of hidden nodes and training sample sizes. The result shows that HBNN can provide not only the predictive distribution but also the heterogeneous parameter estimates for each path.

In this paper, a two-stage approach by integrating independent component analysis (ICA) and data envelopment analysis (DEA) model is proposed for efficiency measurement. Basically, the former aims to search for latent source signals where no relevant signal mixture mechanisms are available; and the latter is a method for measuring the relative efficiencies of decision making units (DMUs). The proposed method firstly uses ICA to the input variables for generating independent components. After selecting the ICs representing the independent sources of input variables, the selected ICs are used as new input variables to DEA model. The experiments from a hospital data have shown that the proposed method can reduce the number of efficient DMUs and improve the discriminatory capability of the efficiency measurement of DEA.

This paper presents a DFT scheme which combines boundary scan with built-in self test for microcontrollers. It focuses on mutual effects between the significant steps in design process and DFT tasks. The steps includes power reduction application in front-end design, discontinuous static timing analysis and clock tree synthesis in back-end design. Our circuit modification for power reduction guarantees the latch's transparence and avoid unacceptable "X" value in logic build-in self test. An improved test point insertion method helps to prevent repetitious logic BIST insertion and static timing analysis. Simple test clock strategy brings out clock tree generation trouble, through change the position of the clock selection logic for DFF who is driven by different clock at different mode, it is resolved perfectly. Based on the experiment on a 450 k gates aerospace application microcontroller, the feasibility of the scheme above is verified.

A combination of classification and regression trees (CART) and neural network techniques is proposed to determine whether the predictive capability can be enhanced in a credit-scoring model. To demonstrate the effectiveness of the proposed approach, these techniques are applied to data from a large bank in Taiwan. In the neural network and the combined model approaches, the backpropagation learning technique, with various learning rates, was extensively studied to determine the connection weights between the neurons. The number of hidden neurons was also varied to determine its effect on the convergence rate. Our results indicate that the proposed combined approach predicts much more accurately and converges much faster than that the conventional CART method or the neural network approach.