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• Bike repositioning problem with service requirements for rental and return requests was studied. • A mathematical model with the goal of minimizing the travel and unsatisfied costs was developed. • An efficient two-phase heuristic approach based on linear programming was proposed. • The proposed approach performs better than CPLEX optimizer and a genetic algorithm-based method. • The effects of various system parameters on the system were also investigated. An approach to overcome the bike imbalance problem is to transfer excess bikes to branches with bike shortages. This study develops a constrained mathematical model to deal with a multi-vehicle bike-repositioning problem, and aims to minimize the sum of transportation and unmet demand costs over a planning horizon through bike-transfer strategies under a minimum service requirement. A two-phase heuristic based on linear programming was proposed to solve the problem and produce compromising solutions. In the first phase, the paper developed a linear programming model to quickly develop decisions related to bike inventory, unloading, and loading for all stations for each time slot. In the second phase, this paper proposed an iterative approach through two parameter sensitive mathematical models to sequentially reduce the problem scale to develop decisions related to bike transfers. Computational results show that the proposed approach is superior to a CPLEX optimizer and a hybrid heuristic based on a genetic algorithm. The proposed approach was used to analyze the bicycle system in Taiwan. The impacts of various system parameters on the system were also investigated. [ABSTRACT FROM AUTHOR]

Abstract Despite prevalent privacy and security threats on the cloud, users have put tremendous amounts of their personal information on cloud storage. This present study proposes a comprehensive research framework to investigate cloud storage users' willingness to put personal information on personal cloud-based storage applications. Our research framework is theoretically derived from the Communication Privacy Management Theory and Privacy-Trust-Behavioral Intention Model. To empirically test our research framework, we conducted an online survey of 786 active cloud storage users both in Indonesia and Taiwan. The findings suggest that cloud storage users' willingness to put personal information is highly influenced by trust, perceived costs, perceived benefits, and also the degree of sensitivity of the personal information. Some findings with regard to cultural differences between the two countries are also showed out. The key findings, implications, and limitations are discussed in this paper. Highlights • Trust influences cloud storage users' willingness to put personal information. • Perceived cost is more apparent when users put more sensitive personal information. • Perceived benefit is more apparent when users put less sensitive personal information. • Institutional privacy assurances are not effective in reducing perceived cost. • Culture influences users' perceptions of privacy in context of cloud storage. [ABSTRACT FROM AUTHOR]

Abstract: Due to the scientific and economic growth of recent years, the on-going innovation in electrical products has enabled people to live more comfortably and conveniently. The standby power function is one such innovation. Unfortunately, as an increasing number of products are equipped with standby power, more energy is wasted and more carbon dioxide is emitted into the atmosphere. This paper combines a two-step proportional stratified sampling technique with systematic random sampling to select representative households in Taiwan. We adopted the measurement method of the International Electro technical Commission (IEC) in measuring the overall use of standby power in Taiwanese households. We then proposed a model for the estimation of standby power consumption, before calculating annual standby power consumption among all households in Taiwan. This paper could serve as a reference for the government and relevant authorities in the establishment of corresponding standards, providing suggestions for the minimization of standby power consumption and the unnecessary waste of energy. [Copyright &y& Elsevier]

Abstract: In order to develop a sound material-cycle society, cost-effective municipal solid waste (MSW) management systems are required for the municipalities in the context of the integrated accounting system for MSW management. Firstly, this paper attempts to establish an integrated cost–benefit analysis (CBA) framework for evaluating the effectiveness of MSW management systems. In this paper, detailed cost/benefit items due to waste problems are particularly clarified. The stakeholders of MSW management systems, including the decision-makers of the municipalities and the citizens, are expected to reconsider the waste problems in depth and thus take wise actions with the aid of the proposed CBA framework. Secondly, focusing on the financial cost, this study develops a generalized methodology to evaluate the financial cost-effectiveness of MSW management systems, simultaneously considering the treatment technological levels and policy effects. The impacts of the influencing factors on the annual total and average financial MSW operation and maintenance (O&M) costs are analyzed in the Taiwanese case study with a demonstrative short-term future projection of the financial costs under scenario analysis. The established methodology would contribute to the evaluation of the current policy measures and to the modification of the policy design for the municipalities. [Copyright &y& Elsevier]

Abstract: Global enterprises require extended logistics operations that integrate channel intermediaries into the network. The method for deriving integrated models for logistics hubs that improve the efficiency of manufacturers’ global operations is the focus of this paper. Under government sponsorship, six industrial logistics hubs were implemented by leading manufacturing sectors across Taiwan over a five year period from 2004 until 2008. Each industry sector had unique industry characteristics, business strategies, and logistics models. Therefore, this paper describes how generalized and quick to implement integrated logistics hubs are developed by studying the successful reference models and systems used by six independent industrial sectors. The research results provide a field tested method for deriving integrated logistics hub models in different manufacturing economies with notes that provide sufficient methodological detail for repeating the construction of logistics hubs in other manufacturing economies. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, six univariate forecasting models for the container throughput volumes in Taiwan’s three major ports are presented. The six univariate models include the classical decomposition model, the trigonometric regression model, the regression model with seasonal dummy variables, the grey model, the hybrid grey model, and the SARIMA model. The purpose of this paper is to search for a model that can provide the most accurate prediction of container throughput. By applying monthly data to these models and comparing the prediction results based on mean absolute error, mean absolute percent error and root mean squared error, we find that in general the classical decomposition model appears to be the best model for forecasting container throughput with seasonal variations. The result of this study may be helpful for predicting the short-term variation in demand for the container throughput of other international ports. [Copyright &y& Elsevier]

Summary: Accurate runoff forecasts are essential for flood mitigation and warning. In this paper, a two-stage flood forecasting model that is based on Support Vector Machine (SVM) is presented. In the first stage, the observed typhoon characteristics and observed rainfall are used to produce rainfall forecast; and in the second stage, the forecasted rainfall and observed runoff are used to produce runoff forecast. A dataset of 16 typhoon storms from Taiwan were used to evaluate the two-stage SVM model. The SVM model generated accurate rainfall and runoff forecasts with a 1–6h lead time, especially for the peak runoff values. A substantial performance improvement of flood forecast is shown for the 4- to 6-h lead time. In conclusion, the SVM model provides an operational advantage by increasing the forecast lead time during typhoon events. [Copyright &y& Elsevier]

Abstract: This paper presents the results of modeling the ionospheric effect of the seismogenic electrostatic field (SEF) seen at the earth’s surface as a perturbation of the vertical atmospheric electrostatic field in the earthquake preparation zone. The SEF distribution at ionospheric altitudes is obtained as an analytical solution of the continuity equation for the electric current density. It is shown that at night, the horizontally large scale SEF can efficiently penetrate into the ionosphere and produce noticeable changes in the horizontal distribution of the F region electron density. The results suggest that the seismogenic electrostatic field could be a possible source for the ionospheric variations observed over Taiwan before the strong Chi Chi earthquake of September 21, 1999. [Copyright &y& Elsevier]

Abstract: Many rivers and streams in Taiwan receive significant BOD and ammonia loads from domestic and industrial wastewaters. These loads are characterized by excessive strength (high concentrations and wastewater flows) – often with great spatial intensity. In many cases, an additional significant load enters the stream before the upstream input is fully stabilized in the receiving water. The classic DO sag and recovery curve in rivers associated with single point source BOD loads (as found in most textbooks) are therefore rare in Taiwan’s rivers. As a result, a different modeling approach must be adopted to address technical challenges associated with modeling for water quality management in Taiwan. In this paper, the modeling results of two rivers in Taiwan are presented to demonstrate the associated technical issues and difficulties, as well as recommend further effort to meet these challenges. [Copyright &y& Elsevier]

Abstract: The objectives of this paper aimed at the characterization of metallic composition and surface analysis on the cruds of fuel rods for unit-1 of boiling water reactor (BWR-6) at Kuosheng Nuclear Power Plant in Taiwan. The inductively coupled plasma- atomic emission spectroscopy (ICP-AES) and gamma spectrometry were carried out to analyze the corrosion product distributions and determine the elemental compositions along the fuel rod under conditions of hydrogen water chemistry (HWC) switched from normal water chemistry (NWC) of plant site in this study. Most of the crud consisted of the flakes and irregular shapes via SEM morphology. The XRD results showed that the loosely adherent oxide layer was mostly composed of hematite (α-Fe2O3) with amorphous iron oxides. The parameters of reactor water chemistry and the available mathematical model for crud deposition were utilized to interpret the chemistry effects on such crud deposition behavior. The fuel surface of this plant appeared to be one with the lower crud deposition. [Copyright &y& Elsevier]

Abstract: The Taiwan Birth Cohort Study (TBCS) is the first nationwide birth cohort database in Asia designed to establish national norms of children''s development. Several challenges during database development and data analysis were identified. Challenges include sampling methods, instrument development and statistical approach to missing data. The purpose of this paper is to describe the pilot study underpinning the TBCS, testing of the TBCS developmental instrument and the resolution of methodological challenges. Bayesian analysis fill in missing data, three-step regression analysis for the investigation of mediating and moderating effect, the use of structural equation modeling in a large scale investigation, investigating direct and indirect effects, confounding factors and reciprocal relationships in children''s development, and used latent growth model in longitudinal observations are described. The TBCS will provide ongoing longitudinal information regarding the predisposing and maintaining factors affecting the long term outcome of pediatric illnesses. [Copyright &y& Elsevier]

Abstract: This paper assesses health risks due to the ingestion of inorganic arsenic from fish and shellfish farmed in blackfoot disease areas by general public in Taiwan. The provisional tolerable weekly intake of arsenic set by FAO/WHO and the target cancer risk assessment model proposed by USEPA were integrated to evaluate the acceptable consumption rate. Five aquacultural species, tilapia (Oreochromis mossambicus), milkfish (Chanos chanos), mullet (Mugil cephalus), clam (Meretrix lusoria) and oyster (Crassostrea gigas) were included. Monte Carlo analysis was used to propagate the parameter uncertainty and to probabilistically assess the health risk associated with the daily intake of inorganic As from farmed fish and shellfish. The integrated risk-based analysis indicates that the associated 50th and 95th percentile health risk are 2.06×10−5 and 8.77×10−5, respectively. Moreover, the acceptable intakes of inorganic As are defined and illustrated by a two dimensional graphical model. According to the relationship between C inorg and IR f derived from this study, two risk-based curves are constructed. An acceptable risk zone is determined (risk ranging from 1×10−5 to 6.07×10−5) which is recommended for acceptable consumption rates of fish and shellfish. To manage the health risk due to the ingestion of inorganic As from fish and shellfish in BFD areas, a risk-based management scheme is derived which provide a convenient way for general public to self-determine the acceptable seafood consumption rate. [Copyright &y& Elsevier]

Abstract: This paper examines the practicability and validity of the Multi-Objective Goal Programming (MOGP) model in designing a point-to-point airline network. The MOGP mathematical model is used in this study to identify and select a best central airport and its connecting airports providing the best overall optimal performance. By using the proposed model in the selection process, one can expect to achieve the following objectives: (1) an airline network designed at less cost, (2) an airline network that generates more revenues, and (3) an airline network that serves more passengers. Route data from Taipei to the Southeast Asian region were selected for this experiment to validate the model’s practicability. [Copyright &y& Elsevier]

Abstract: In this paper, we proposed a modified turbulent particle swarm optimization (named MTPSO) method for the temperature prediction and the Taiwan Futures Exchange (TAIFEX) forecasting, based on the two-factor fuzzy time series and particle swarm optimization. The MTPSO model can be dealt with two main factors easily and accurately, which are the lengths of intervals and the content of forecast rules. The experimental results of the temperature prediction and the TAIFEX forecasting show that the proposed model is better than any existing models and it can get better quality solutions based on the high-order fuzzy time series, respectively. [Copyright &y& Elsevier]

Summary: This paper describes the development of flood forecasting models to improve the long lead-time flood forecasting performance. To investigate the influence of typhoon characteristics on flood forecasting, four different types of model inputs are designed to yield 1- to 6-h ahead forecasts of runoff. The most appropriate lengths of model inputs, namely rainfall, runoff and typhoon characteristics, are then determined. A performance comparison of models with and without typhoon characteristics is made. In addition to the conventional performance measures, based on the viewpoint of early warning three measures regarding effective warnings are also proposed to evaluate the forecasting performance. With typhoon characteristics as input to the model, the forecasting performance is significantly improved for both medium and long lead-time forecastings, especially when the rainfall data are not available. It is also found that the forecasting model without typhoon characteristics cannot provide any effective warnings for long lead-time forecasting. [Copyright &y& Elsevier]

Abstract: Two sub-technologies, pig production and wastewater control, in pig farm operation are considered. This paper develops a multi-activity DEA (data envelopment analysis) model to simultaneously measure productive efficiency (PE) and environmental efficiency (EE) in farrow-to-finish pig production in Taiwan, and to explore several theorized causal relationships between performance and farm-specific knowledge. The empirical results prove that the estimated PE and EE do not belong to the same distribution. That suggests that using an identical ‘technical efficiency’ index to represent PE and EE would get a biased result when undesirable outputs are considered. PE is higher than EE, but the two are positively correlated. Analytical results support the presence of economies of scale in sample farms. Providing training to farmers and computerizing farm operations are critical determinants of PE; providing training to operators of wastewater control facilities and the operator''s education level showed a positive impact on EE. Such information is valuable for both farmers and the authorities in making decisions to enhance productivity and environmental protection in the pig sector in Taiwan. [Copyright &y& Elsevier]

Abstract: This paper introduced a stochastic programming model to address the air freight hub location and flight routes planning under seasonal demand variations. Most existing approaches to airline network design problems are restricted to a deterministic environment. However, the demand in the air freight market usually varies seasonally. The model is separated into two decision stages. The first stage, which is the decision not affected by randomness, determines the number and the location of hubs. The second stage, which is the decision affected by randomness, determines the flight routes to transport flows from origins to destinations based upon the hub location and realized uncertain scenario. Finally, the real data based on the air freight market in Taiwan and China is used to test the proposed model. [Copyright &y& Elsevier]

Abstract: This paper investigates the Granger causality between electricity consumption (EL) and economic growth for Taiwan during 1980–2007 using the cointegration and error-correction models. The results indicate that EL and real GDP are cointegrated, and that there is unidirectional short and long run Granger causality from economic growth to EL but not vice versa. Considering cointegrated property, this study proposes a new error-correction state space model (ECSTSP) with the error-correction term (ECT) in its state vector to forecast both EL and real GDP simultaneously, whereas the ECM is not in the state vector of classical state space model (STSP). The out-of-sample forecasting ability of the ECSTSP is compared with STSP and SARIMA models using six forecasting horizons from 1-year to 6-year. The results suggest that all of the models have strong forecasting performance with MAPE less than 5.4%, but the ECSTSPs have the smallest average values of MAPEs for both EL and GDP, which are 2.50% and 1.74%, respectively. For short-term predictions, SARIMA models are as good as STSP or ECSTSP ones. For long-term prediction, ECSTSP is the best model, because the cointegration relationship between real GDP and EL is taken into account in this model. [Copyright &y& Elsevier]

Abstract: This paper seeks to investigate the relationship between business air travel and videoconferencing for intra-firm communication using econometric models developed through survey data from Taiwan’s technology industry. The survey respondents include business firms that either use or do not use videoconferencing currently. Based on survey data analyses, negative binomial models are developed for the set of current adopters of videoconferencing, and a Poisson regression model is developed for the non-adopters. They suggest substitution relationships between business air travel and videoconferencing for the two groups. However, the substitution effect is perceptibly stronger when videoconferencing is used as a substitute for business air travel. The analysis highlights that the meeting context significantly influences the choice of the communication mechanism; meeting contexts that do not specifically require face-to-face interaction tend to foster increased videoconferencing usage. Further, the perceptions of the respondents in terms of the relative benefits and weaknesses of each communication option influence the likelihood of substitution. [Copyright &y& Elsevier]

Abstract: The total consumption of electricity and petroleum energies accounts for almost 90% of the total energy consumption in Taiwan, so it is critical to model and forecast them accurately. For univariate modeling, this paper proposes two new hybrid nonlinear models that combine a linear model with an artificial neural network (ANN) to develop adjusted forecasts, taking into account heteroscedasticity in the model''s input. Both of the hybrid models can decrease round-off and prediction errors for multi-step-ahead forecasting. The results suggest that the new hybrid model generally produces forecasts which, on the basis of out-of-sample forecast encompassing tests and comparisons of three different statistic measures, routinely dominate the forecasts from conventional linear models. The superiority of the hybrid ANNs is due to their flexibility to account for potentially complex nonlinear relationships that are not easily captured by linear models. Furthermore, all of the linear and nonlinear models have highly accurate forecasts, since the mean absolute percentage forecast error (MAPE) results are less than 5%. Overall, the inclusion of heteroscedastic variations in the input layer of the hybrid univariate model could help improve the modeling accuracy for multi-step-ahead forecasting. [Copyright &y& Elsevier]

Southern Taiwan has experienced severe PM10 problems for over a decade. The present paper describes the establishment of a simulation model for the daily average PM10 concentrations at Ta-Liao, southern Taiwan. The study used a regression with time series error models (RTSE models) (multivariate ARIMA time series model), including an explanatory variable resulting from principal component analyses to complete the PM10 simulation. Factor 1 estimated from the factor analyses explained the variance of 44–49%, which indicated the important contribution from the neighbor-city PM10 at Mei-Nung, Lin-Yuang, Zuoying, Chao-Chou, local ozone and NOx. Factor 1 can be interpreted with regional PM10 plus photochemical reactions. To improve the predictability of extremely high PM10, different results from the principal component analysis were introduced to the RTSE models. We constructed four kinds of RTSE models: RTSE model without PC, with PC4S (PM10 at Mei-Nung, Lin-Yuang, Zuoying, and Chao-Chou), with PCTL (meteorological variables and co-pollutants at Ta-Liao), and with PCTL4S (the combination of the above two) and evaluated the statistics model performance. Ozone, dew point temperature, NOx, wind speed, wind directions, and the PC trigger were the significant variables in the RTSE models most of time. When the neighbor-city PM10 was included in the PC trigger, the predictability was apparently improved. The closeness of fit with the inclusion of PC4S and PCTL4S was improved by reducing SEE from 0.117 to 0.092. Using the RTSE models with PC4S or PCTL4S, POD was improved by an increase of 33%, FAR was reduced 30%, and CSI was increased 39%, when simulating the daily average PM10 >150μgm−3. Evidently we need to survey source impacts prior to establishing a simulation model. Factor analysis is a useful method to investigate sources that contributed PM10 to a target site prior to establishing a simulation model. [Copyright &y& Elsevier]

Abstract: In this paper, the global irradiation observed in Taiwan from 1990 to 1999 was used to estimate the optimal tilt angle for solar collectors. The observed data are resolved into diffusion and beam components, and transformed into instantaneous time frames using mathematical models. The energy gain on installing a single-axis tracked panel as compared to a traditional fixed panel is originally analyzed theoretically. In addition to the observation data, both types of radiation will be taken into account for comparison, i.e. both extraterrestrial radiation and global radiation predicted using empirical models. The results show that the yearly optimal angles for six selected stations are about 0.95 and 0.88 times their latitudes for extraterrestrial and predicted radiation, respectively. All of the observed irradiations are less than the predicted values for all times and stations, consequently resulting in a flatter tilt angle, with a few exceptions in summer. Since Taipei has the lowest clearness index, its yearly optimal angle calculated from observed data shows the greatest discrepancy when compared to its latitude. By employing a tracked panel, the yearly gains calculated from the observed data lie between 14.3% and 25.3%, which is significantly less than those from the extraterrestrial and predicted radiations. [Copyright &y& Elsevier]

Abstract: From the government''s perspective, it is very important to estimate the growing path of the mobile Internet market and then to forecast the trend. The purpose of this paper is to propose a diffusion model that reveals the growth pattern of the mobile Internet subscriber in Taiwan utilizing the concepts of the “technical substitution” and the “multi-product competition”, which suits the characteristics in the mobile Internet market in Taiwan. From the regression results, the estimated ultimate market potential of GPRS is 6.4 million, which is going to saturate in about 2008Q1. On the other hand, the estimated range of the market potential of PHS/3G is about 7.2 to 8.0 million. That is, the total mobile Internet market in Taiwan is forecasted to be around 13.6 to 14.4 million subscribers. [Copyright &y& Elsevier]