Taiwan Railways Administration Research Articles

The modal frequencies and effectiveness in vibration reduction of direct-fixation track on viaduct

ABSTRACT Replacing conventional ballast track, direct-fixation tracks (DFTs) are supposed to generate less noise and vibration; however, the authorities obtain more complaints by metropolitan residents. In order to investigate the modal frequencies of DFTs, field tests were performed on viaduct with I-shape concrete girder on Western Trunk Line of Taiwan Railway Administration (TRA). Experimental modal analysis (EMA) was first conducted to capture the natural frequencies of DFT and frequency response function of the system. Vehicular vibrations were then measured to obtain the insertion loss of elastic baseplate and the frequency spectrum to reveal the effectiveness of DFTs in vibration reduction. The free vibration of the bridge after vehicle passing through was also collected to verify its nature frequencies. According to the results of field tests, the dynamic behavior of elastic baseplate should be considered in the system. To ensure those results, a finite element DFT model was established and given by the same hammer excitation from EMA. The findings from field tests match our finite element analysis, which have demonstrated that the major frequencies of DFT are not only close to 100 Hz and 630 Hz, respectively, but the mass of the elastic baseplate should not have been overlooked in simulation.

The Preservation of Tracing Paper: A case Study of TRA Archives

Taiwan is located within a subtropical region where the preservation of tracing paper is challenging, given its susceptibility to changes in humidity. Although the National Archives Administration (NAA) currently provides a controlled environment for the repositories of the National Archive, this archive has sustained damage and deterioration due to a legacy of compromised storage and inherent fragility of its contents. Of particular interest are the collective holdings of the Taiwan Railways Administration (TRA), the Ministry of Transportation and Communications (MOTC). Historically, these holdings were originally known as ‘The Railway Department of the Traffic Bureau, under the General Governor of Taiwan’, during Japanese colonial governance. This specific collection dates from 1895 to 1997 and includes over 10,000 engineering drawings. Previously, the NAA had implemented linings to both repair damage and aid in the preservation of the physical archives. However, this study compares this approach with an alternative humidification method using Gore-Tex® to relax and flatten these drawings on tracing paper. The focus of this paper is to evaluate dimensional change as a result of these treatments and to make recommendations in regards to their respective suitability for addressing the condition of the TRA collection.

Internal resource mobility of a railway administration: A three-phase centralized data envelopment analysis

Railway transportation in Taiwan is not only one of the important means of transportation in the populous western corridor, but also a main mode of transportation in the eastern corridor. However, due to the poor operating condition of its railways, the Taiwan Railway Administration has been running at a loss. To reduce losses and improve performance, the operators of railways in Taiwan should more effectively allocate internal resources between train stations. Since the train stations are managed by the centralized administration, the Taiwan Railway Administration pursues overall performance. Hence, this paper constructs resource allocation methods based on centralized data envelopment analysis, and further proposes a three-phase method to understand the situation involving increased or decreased resources for each train station, and determines the internal resource mobility between train stations. By building resource allocation models, this paper can provide the railway operators with extensive information to effectively reallocate resources.

Applying Constraint Programming and Integer Programming to Solve the Crew Scheduling Problem for Railroad Systems: Model Formulation and a Case Study

Crew scheduling is one of the crucial processes in railroad operation planning. Based on current regulations and working and break time requirements, as well as the operational rules, this process aims to find a duty arrangement with minimal cost that covers all trips. Most past studies considered this subject for railroad systems as an optimization problem and solved it with mathematical programming-based methods or heuristic algorithms, despite numerous logical constraints embedded in this problem. Few studies have applied constraint programming (CP) approaches to tackle the railroad crew scheduling problem. This paper proposes a hybrid approach to solve the problem with a CP model for duty generation, and an integer programming model for duty optimization. These models have been applied to the Kaohsiung depot of Taiwan Railways Administration, the largest railroad operator in Taiwan. The encouraging results show that the proposed approach is more efficient than the manual process and can achieve 30% savings of driver cost. Moreover, the approach is robust and provides flexibility to easily accommodate related operational concerns such as minimizing the number of overnight duties. Thus, this hybrid two-phase approach seems to have the potential for applications to the railroad crew scheduling problems outside Taiwan.

Exploring Intercity Trip Patterns of Railway Systems on National Holidays Using Deep Auto-Encoder

Intercity railway system operation on national holidays can be challenging because of possible surging demand. This study proposes an analysis framework to investigate railway system ridership data on national holidays, seeking to attain better understanding of relevant intercity trip patterns, so as to enable enhanced preparation and response before and during national holidays. The ridership data are analyzed in the form of Origin–Destination (O-D) tables and regarded as pictures of N × N pixels, where N is the number of the considered stations/cities in a railway system. The framework primarily adopts a deep auto-encoder to process these pictures to reduce data dimensions and abstracting key features within these pictorial data. Based on the abstracted features, k-means clustering is then conducted to categorize the O-D tables with similar trip patterns into the same group. Further, a discrete outcome model based on logistic regression is developed on the clustering results to enhance the interpretation of the trip pattern in each group and identify the significant holiday-related characteristics and external factors that can affect the trip pattern generation. The ridership data of Taiwan Railways Administration associated with 38 national holidays from January 2014 to August 2018 are analyzed. The analysis results highlight insightful interpretation in relation to clustered trip patterns and relevant trip characterization relative to various national holidays. The proposed framework and developed discrete outcome model are also validated, showing 85% correct assignments of O-D tables to the groups of relevant trip patterns.

REVIEW OF PROBLEMS IN THE DEVELOPMENT OF RAIL TOURISM IN TAIWAN, ON THE EXAMPLE OF THE ALISHAN FOREST RAILWAY

Rail tourism is significant in boosting Taiwan’s tourism industry with more than 560,000 tourists visited Alishan railway, one of the most significant heritage rail tourism sites in 2018. However, recently more attentions and efforts were being put on High-Speed-Rail instead of heritage rails in Taiwan. As the Taiwan Railways Administration launched the 10 years plan in replacing the heritage rail, it has raised the question of sustainability of the heritage rail tourism in Taiwan. The study aims to assess the challenges faced in developing heritage rail tourism in Taiwan by using the Porter’s Diamond Model as the assessment criteria. The data was collected through a variety of methods inclusive of interviews, observations, and review of challenges faced in the process of preparing the existing heritage railways for the future of Taiwan’s rail tourism. This study found that despite the popularity, financial subsidies and extensive promotion effort by Taiwan Railways Administration, the heritage rail tourism in Taiwan is still facing difficulties in remaining sustainable in the long-run due to inefficient firm strategy, poor pricing strategy, and also non-user-friendly online ticketing system.

Simulation-Based Method of Capacity Utilization Evaluation to Account for Uncertainty in Recovery Time

A typical objective of a railway agency is to design an efficient and reliable service plan. Although enhancing the level of capacity utilization may increase efficiency, the stability of the service plan may also decrease due to stochastic railway disruptions. Past studies used recovery time to evaluate the stability of a service plan; however, the variation of recovery time was not fully examined. Therefore, we developed a Monte Carlo simulation framework to address this issue and proposed four capacity-based indices for the evaluation of service efficiency and stability. These indices are capacity utilization efficiency, mean recovery time, dispersion of recovery time, and probability of unacceptable recovery time. The latter two new indices explored the variation of recovery time and probability of unacceptable long recovery time, which is undesired for railway operation. We conducted a real-world case study on the Taiwan Railways Administration before and after the service plan revision. Consequently, the northbound service plan needed a deliberate review and revision before implementation, whereas the southbound plan successfully increased capacity usage while not necessarily worsening stability. This result demonstrated that our study introduced uncertainty analysis into the evaluation framework and provided flexible information on the service plan. These developments can provide improved support in the decision-making of railway agencies to strike a balance between service level and asset usage.

Performance evaluation of the Taiwan railway administration

This study aims to investigate the effects of centralized allocation and optimization of railway resources on overall operational efficiency of the railway industry. Its results are intended to help Taiwan railway industry in resource allocation and reduction of organization resistance caused by resource deployment in Taiwan. For this purpose, this study proposes and divides resource reallocation into long-, middle-, and short-term plans, with three resource adjustment programs. These programs consider different geographical ranges and resource conditions of personnel and equipment in resource allocation by using a two-phase centralized data envelopment analysis. Conducted in 2011, the Taiwan railway data analysis indicated that high overall output that was attributed to efficient allocation of resources induced large-scale organizational changes and adjustments (such as staff reduction) in the railway industry. These changes resulted in widespread organization resistance. Nonetheless, this process enabled the railway industry in Taiwan to achieve balance between output and organization resistance under different environments efficiently.

Grouting to remove piles from a tunnelling machine cutter-head

This paper provides a summary report on measures taken to remove embedded steel ‘H' pile obstacles from the cutter head of an advancing tunnel-boring machine. The piles were part of the soil-mixing retaining wall built for the cut-and-cover tunnel construction of a Taiwan high-speed rail tunnel and a Taiwan railways administration tunnel, which were directly above the mass rapid transit tunnel that was to be constructed. The collision zone between the boring machine and piles was below groundwater level and was approximately 23 m below the ground surface in a silty sand layer. To remove the piles safely from the cutter head, horizontal grouting from two adjacent work pits was conducted for waterproofing and solidification purposes. By controlling the amount of soil being flushed out during the grout hole drilling first, and also the pressure used for grouting later, the measured tunnel settlement resulting from grouting was negligible. Because of the favourable watertightness of the grouted zone and the dewatering influence of a nearby construction site, pile removal was conducted under particularly dry working conditions. In total, 12 piles were identified in the collision zone and were successfully removed from the cutter head by hand tools.

Public service motivation and job performance in public utilities

Purpose – The purpose of this paper was to examine the predictive power of each dimension of public service motivation (PSM) on job performance (JP) in a Taiwan sample. Design/methodology/approach – The present study adopted a cross-sectional approach using a large-scale questionnaire survey in Taiwan (N=2,239). Participants from six utility sectors in two infrastructure-relevant ministries (Ministry of Transportation and Communications (MOTC) and Ministry of Economic Affairs (MOEA)), with heterogeneous sectors, were recruited, including representatives of the Taiwan Railways Administration (TRA), Chunghwa Post (CHP), Taiwan Power Company (TPC), CPC Corporation, Taiwan (CPC), Taiwan Sugar Corporation (TSC), and Taiwan Water Supply Corporation (TWSC). The sample consisted of 2,239 public employees from six public utilities. Findings – Although the results suggest that the PSM observed in western society also exists in the Taiwanese public utilities context, the self-sacrifice (SS) and the compassion (COM) ...

Diversification Performance Evaluation of Post Offices in Taiwan from Customers’ Viewpoints

Diversification adds values and increases profits to the company, and more and more post offices around the world use diversification strategies either postal or non-postal services to increase profitability. Chunghwa Post, a state-owned enterprise in Taiwan, intends to use its infrastructure for diversification to gain revenues from non-postal products and services. This case study first summarizes the satisfaction levels of five diversified products and services provided by Chunghwa Post and then makes a comparison between Chunghwa Post and its rivalries in terms of performance evaluation from customers’ viewpoints. The results show that some demographic variables have different satisfaction levels in diversified products and services statistically. In addition, Chunghwa Post has the advantage over Taiwan Railways Administration when train tickets can be picked up from post offices whereas Chunghwa Post has the disadvantage in online shopping mall services. By figuring out the strengths and weaknesses of diversified products and services, the management can decide if a particular diversified product or service is to be disregarded or vice versa. Therefore, marketing strategies can be designed for a particular diversified product or service in order to gain competitive advantage in the future.

An implicit enumeration algorithm for the passenger service planning problem: Application to the Taiwan Railways Administration line

In a passenger railroad system, the service planning problem determines the train stopping strategy, taking into consideration multiple train classes and customer origin–destination (OD) demand, to maximize the short-term operational profit of a rail company or the satisfaction levels of the passengers. The service plan is traditionally decided by rule of thumb, an approach that leaves much room for improvement. To systematically analyze this problem, we propose an integer program approach to determine the optimal service plan for a rail company. The formulated problem has a complex solution space, and commonly used commercial optimization packages are currently incapable of solving this problem efficiently, especially when problems of realistic sizes are considered. Therefore, we develop an implicit enumeration algorithm that incorporates intelligent branching and effective bounding strategies so that the solution space of this integer program can be explored efficiently. The numerical results show that the proposed implicit enumeration algorithm can solve real-world problems and can obtain service plans that are at least as good as those developed by the rail company.

Development of Rail Service Sensitivity Meter

Understanding passenger expectations is a major task for rail transit operators so that they can determine necessary service improvements and the need to undertake new resource planning projects. Taiwan Railways Administration (TRA), the commuter rail operator in Taiwan, is seeking an approach to identify customer expectations by types of services and by region. Level of service (LOS) as defined by the Transit Capacity and Quality of Service Manual (TCQSM) is a widely used approach to evaluate the performance of transit services. However, predefined thresholds from the TCQSM used to evaluate service quality without knowing customer expectations may not reflect actual passenger satisfaction. In this study, a rail service sensitivity meter (RSSM) was developed to measure passenger expectations accurately and quantitatively and to determine acceptable levels of rail service. The RSSM was implemented in the empirical study to determine passenger expectations in regard to an acceptable LOS obtained through the process. Results of the empirical study set the benchmarks of service quality attributes and indicate that TRA service performance is generally acceptable, but TRA should focus on improvements to passenger load during peak hours by lengthening current trains with additional seats or by providing additional train services. Through the RSSM process, operators can evaluate the gap between expected services and actual services as well as improve the system to ensure customer satisfaction.

Development of Analytical Capacity Models for Conventional Railways with Advanced Signaling Systems

Railways around the world are experiencing growth in traffic demand and the need to expand their network and line capacity. To accommodate the substantial demand, the conventional railway operator in Taiwan, the Taiwan Railways Administration (TRA), is interested in understanding the potential benefit of adopting various advanced signaling systems, such as hybrid or moving-block systems. In this study, the authors developed a set of analytical capacity models for conventional rail operations with advanced signaling systems, which were implemented in the busiest corridor in the TRA system. The empirical results show that advanced signaling systems generally have positive capacity effects. However, the benefit may not be substantial due to constraints from the station track layouts. Therefore, possible capacity improvement alternatives, such as improving track layouts and upgrading signaling systems, should be considered together to determine the optimal capacity improvement plan. The use of these proposed capacity models can help railway agencies with similar operational environments in their capacity management and resource planning projects.

Ant colony optimization for railway driver crew scheduling: from modeling to implementation

This study addresses the crew-scheduling problems for railway drivers’ duty trips on a railway timetable represented as a time–space diagram. Based on the diagram, the railway driver-scheduling problem is then transformed into an arc routing problem (ARP). Because of the special properties and features of the problem, the ARP can be treated as a typical vehicle node routing problem. The Ant Colony Optimization algorithm is employed to solve the transformed problem. Real data from the Taiwan Railways Administration are used to test the proposed models and algorithm. The results showed that the dead-heading-allowed approach is able to obtain a better solution in terms of fewer drivers and shorter idle time.

Simply Level Recalculation Using Statistical Approach

A railway is a strip-shaped corridor usually divided into multiple sections that are constructed separately. Associated construction contracts must consider scheduling. Because a railway is a continual linear structure, high-precision level surveys are needed for rail sections to connect smoothly. However, the different phases and sections of construction require multiple-level surveys, which often lead to bias in the benchmarks. Since the railway is a continuous alignment, and an inconsistent elevation system affects the civil work and subsequent track laying. This study therefore used a statistical method to eliminate inconsistencies in benchmarks. Statistics are widely used in engineering and in daily life, to solve decision making problems involving uncertainties. This study used the expected value of closing error between benchmarks as an index for recalculating level, and used the standard error of expected value as the accuracy index. Application of the proposed method using measurement data for a Taipei underground project of the Taiwan Railway Administration showed that it eliminates bias in benchmarks and provides the required accuracy for closure between adjacent points.

RFID system for public train transportation

ABSTRACTNowadays, the problem of a shortage of energy is becoming more and more serious. This has resulted in the global governments' appeal to people to take public transportation systems as much as possible. But, the public transportation system has a lot of problems that cause people's interest in taking the public transportation system to get lower and lower. For example, many passengers use many kinds of management loopholes to avoid buying tickets. This action forces the companies involved in providing the public transportation system to strengthen manpower for inspecting tickets. Hence, the companies will shift cost to the customers forcing ticket prices higher and higher as well as passengers becoming more frustrated with the increase in inspecting tickets. In this paper, we take the Taiwan Railways Administration (it owns different ticket types and different train types in the same public transportation system) as our implement environment and we use Radio‐Frequency Identification (RFID) methods conforming to EPCglobal Class 1 Generation 2 (C1G2) standards to solve this train‐jumping problem and reduce the manpower cost of the public transportation system companies. And most importantly, our scheme also enhances higher security. Copyright © 2010 John Wiley & Sons, Ltd.

A Study on the Noise Exposure and Hearing Loss of the Diesel-Electric Locomotive Maintenance Workers in Taiwan Railways Administration

ISEE-0351 Background and Objective: According to previous results of our study, the diesel-electric locomotive showed the highest sound level compared with other locomotives of Taiwan Railways Administration (TRA). This investigation chose the Taipei Railway Workshop of TRA investigate the relationships between the noise exposure and hearing loss in the workers. Methods: The study subjects were divided into an exposed group including the workers involved in horsepower test, engine inspection, electrical inspection and repair jobs, and a control group comprised of office administration staff. The sound pressure levels were measured in the workplace near workers by Sound Level Meter (Larson Davis Inc., 824). Moreover, the personal noise dose and hearing were measured by dosimeter (Larson Davis Inc., SPARK 706) and air conduction audiometer (Danplex, AS 42) for the exposed group and control group, respectively. Results: Among the job categories, the horsepower test had the highest sound pressure level average (94.9 dB-A), followed by the engine inspection (81.9 dB-A), the electrical inspection (79.6 dB-A), and finally the repair job (72.6 dB-A). The average personal noise doses of an 8-hour work time of the four job categories were measured and are, in order, the horsepower test (268.4%), the engine inspection (152.6%), the electrical inspection (129.2%), and the repair job (28.7%). By the workers’ audiometric tests, except for 4k, 6k Hz generally appearing in occupational hearing loss, both the exposed group and the control group had hearing loss in low audio frequency. Conclusion: Based on Taiwan’s labor safety and health regulations, the noise doses of the workers of horsepower test, engine inspection, and electrical inspection had already surpassed the standard working level. Although the TRA has implemented exposure time management to conform to the regulatory requirement, it should still pay attention to the hearing protection.

Optimization of the Long-Term Capacity Planning Process for Taiwan Railway Administration

Optimization of the Long-Term Capacity Planning Process for Taiwan Railway Administration

Effect of consecutive driving on accident risk: A comparison between passenger and freight train driving

This study combined driver-responsible accidents with on-board driving hours to examine the effect of consecutive driving on the accident risk of train operations. The data collected from the Taiwan Railway Administration for the period 1996–2006 was used to compute accident rates for varied accumulated driving hours for passenger and freight trains. The results showed that accident risk grew with increased consecutive driving hours for both passenger and freight trains, and doubled that of the first hour after four consecutive hours of driving. Additional accident risk was found for freight trains during the first hour due to required shunting in the marshalling yards where there are complex track layouts and semi-automatic traffic controls. Also, accident risk for train driving increased more quickly over consecutive driving hours than for automobile driving, and accumulated fatigue caused by high working pressure and monotony of the working environment are considered to be the part of the reason. To prevent human errors accidents, enhancing safety equipment, driver training programs, and establishing a sound auditing system are suggested and discussed.