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JOB shops, EMPLOYEES, RAILROAD station design & construction, MACHINE-shop practice, and HETEROGENEITY

Most shops in practice are constrained by more than one resource. Consequently, a large body of literature on dual resource constrained shops has emerged. This research typically focuses on worker assignment rules, with attention being on when and where to move workers. In contrast, the decision concerning who to reallocate to a station has received limited attention. The limited prior work assumes workers are assigned to a new station as soon as they become available or seeks to minimise the risk of worker idleness. Using simulation, we question this assumption and show that it can be beneficial to introduce additional worker idleness to ensure workers only work at their most efficient station(s). In general, it is less likely that there are several workers available for one station than it is for there to be multiple stations available for one worker. Consequently, the Who Rule is used less frequently than the Where rule and has less of an impact on performance. Finally, considering the criticality of work orders as part of the Where Rule is important in assembly shops; but if labour is heterogeneous then the focus should be on efficiency. The findings have important implications for research and practice. [ABSTRACT FROM AUTHOR]

RAILROAD bridges, SHAKING table tests, HIGH speed trains, EARTHQUAKE intensity, EARTHQUAKES, RAILROAD rails, and SOIL vibration

Rail irregularity is the leading cause of enhancing train-track coupling vibration and, therefore, should be studied in detail for safety requirements. In this study, the differences between existing rail irregularities without being subjected to an earthquake between different countries were first studied. Results show that existing power spectrum density and time-domain displacement samples of rail irregularities in the American code are the largest, while the irregularities of the Germany railway are higher than those of China in a specific range of rail wavelengths. Afterward, the effects of earthquake intensity, soil site, and duration on the rail irregularity of a Chinese typical high-speed railway bridge were investigated. For this purpose, a finite element model was established and validated by the shaking table test of a 1/12-scaled high-speed railway bridge experimental specimen. The calculation results indicated that the influences of earthquakes on the rail alignment irregularity were evident. [ABSTRACT FROM AUTHOR]

Home prices, Public transit, Metropolitan areas, Railroad stations, and Transit-oriented development

Constructing multimodal stations is one of the considered ways to implement transit-oriented development (TOD), with the goal of synergizing land use and transportation to promote both greater transit accessibility and sustainability in urban areas. Improvements in such accessibility have led to an uplift in land value and housing prices. These price changes have been primarily studied by analyzing the effects of proximity to stations of a single line or multi-line mass rapid transit (MRT) system. However, little attention has been paid to investigating the effects of different types of multimodal MRTs and railway joined stations. The aim of this study is to investigate the different types of multimodal stations in Kaohsiung City, Taiwan. We use publicly available housing transaction data to construct hedonic price models. The results show that in the Kaohsiung MRT stations, an increase of 100 m in distance from the stations results in a TWD 258,0001 decrease in the average housing price. The housing price elasticity with respect to a 1% increase in distance from these stations is -0.067%. [ABSTRACT FROM AUTHOR]

RAILROAD trains, VEHICLES, and WHEELS

For the worn state of the wheel, metro vehicles often suffer a serious carbody swaying issue, which causes the lateral stability of the vehicle to exceed the limit and affects the ride comfort. An experimental test was carried out on this investigation to study the carbody swaying of the metro vehicle. The field results show that the vehicle system vibrates at around 2.5 Hz in the lateral direction, which leads to the low-frequency swaying on the carbody. In order to explore the formation mechanism of the carbody low-frequency swaying and its relationship with the geometry matching of wheel-rail contact, measured rail and wheel profiles are employed to present a comparative analysis with respect to the initial contact geometry. A multibody dynamic railway vehicle system is established further. Time-domain simulations state that the 2.5 Hz vibration on the carbody belongs to the natural frequency of the vehicle, and the amplitude is larger for the measured wheels than that of the standard wheel profiles. By using the root-locus method, it can be determined that the 2.5 Hz vibration corresponds to the upper swaying mode of the carbody. With the increase in the wheel-rail equivalent conicity, the hunting frequency of bogie increases gradually, which converts frequency with the upper swaying frequency of carbody and leads to carbody low-frequency swaying. [ABSTRACT FROM AUTHOR]

INTERNATIONAL economic integration, RAILROAD trains, INTERNATIONAL trade, SYSTEMS theory, and SUSTAINABLE development

The China-Europe Freight Train (CEFT) serves as an important carrier and platform for international economic cooperation and international trade circulation between China and Europe. Since it worked, its actual operation and development have been affected by many factors, but the level of its actual operating efficiency and the main affecting factors of CEFT have been difficult to find, which has severely limited its sustainable development. Therefore, this paper scientifically selected the operation efficiency evaluation indicator system of CEFT and combined grey system theory, cross-efficiency method, and DEA to construct a new DEA evaluation model based on grey cross-efficiency, which can not only overcome the problem of ignoring the relative importance ratings of the evaluation indicator in the general DEA evaluation model and the traditional cross-efficiency DEA evaluation model but also more accurately evaluate the actual operation efficiency of CEFT. At the same time, based on the actual operating data of CEFT from 2011 to 2018 and the above new evaluation models, the CEFT's operation efficiency was evaluated and tested by examples, showing that on the one hand, the grey cross-efficiency DEA evaluation model can more accurately evaluate the actual operation efficiency of CEFT than other traditional evaluation models; on the other hand, it is found that the "overseas cities," "operating lines," and "entry-exit nodes" are currently the main factors that limit the actual operation efficiency of CEFT and indicating improvement direction for the future efficient and sustainable development of CEFT. [ABSTRACT FROM AUTHOR]

ROAD safety measures, RAILROAD passenger cars, TRAFFIC safety, TRAFFIC accidents, HUMAN error, and SYSTEM safety

Strengthening road safety in the face of the enormous development of the automotive in recent decades is crucial. The safety benefits of automated vehicles are paramount. Automated vehicles have the potential to remove human error in road traffic, which will help protect drivers and passengers, as well as pedestrians and bicyclists. The carried-out forecasts are pioneering for Polish road traffic conditions. In England, studies have been carried out to determine the estimated impact of autonomous vehicles on road safety in simulated traffic conditions on the motorway. In Poland, preliminary forecasts of the reduction in the number of road accidents were made; however, they were based on other assumptions. Therefore, estimating the impact of using autonomous vehicles in order to increase the level of road safety is an innovative activity for Polish road conditions. For the purposes of this article, available statistical data on vehicles registered in Poland, their equipment with advanced driver-assistance systems as well as accident data and their causes were analyzed. A diagnosis of Road Safety in Poland in 2018 (base year for further estimations) was made, taking into account the trend of recent years together with an indication of the most common causes of road accidents. These data were compiled with statistical data from other countries about the influence of driversupport systems on traffic safety. Possible potential for increasing Road Safety in Poland by the year 2030 was estimated. The analyses were prepared assuming different types of processes related to traffic, road safety, and the recent development of the passenger car fleet in Poland. Presented results show four scenarios of road safety change, where the number of accidents is reduced with statistical average of 5000 reduction in the year 2030. These expectations are based on various predictable factors connected with upgrade of car fleet quality and take into account changes in road safety observed in recent years. Based on the current trend of driving automation and rapid development of driver-support systems, the provided estimations were found reliable and likely. The conducted research shows the benefits and the need for the use of driver-assistance systems in vehicles as they can measurably affect the level of road safety. [ABSTRACT FROM AUTHOR]

RAILROAD rails and SERVICE life

Contact stress between wheel and rail is believed to cause damage to the rail. The relationship between the contact stress and the radius of the rail is initially based on the Hertz contact theory. By adjusting its radius, the rail profile is designed with an objective of reducing the maximal contact stress between wheel and rail. The rail profile of turnout is parameterized by defining several control cross sections along the switch. The experiment of dynamic vehicle-turnout interaction is also carried out to investigate the effect of the improved rail profile on the dynamical behavior of the vehicle. The method is then verified through examples using rail profile with a switch width of 20 mm and LM worn-type tread at the CN60-350-1:12 turnout. The results show that the designed rail has a higher matching degree with the wheel profile. It can reduce the contact stress, improve the wheel-rail contact state, and prolong the service life of the rail without deteriorating the dynamic performance of the vehicle passing through the turnout. [ABSTRACT FROM AUTHOR]

ACTIVE noise control, RAILROAD passenger cars, MICROPHONES, REAL-time control, and ALGORITHMS

A new algorithm for controlling sound quality actively in a car cabin using a virtual error microphone (VEM) is considered in this paper. Active sound quality control (ASQC) is known to improve engine sound in a cabin by canceling boomings and enhancing some engine order sound at the same time. The VEM based ASQC (VEM-ASQC) algorithm in this study is devised to relocate a controlled sound zone formed at an error microphone position to the driver's ear position where a virtual error microphone locates. Since the error microphone just by the driver's ear can block free movement of the driver's head, the error microphone can be positioned just beneath the ceiling in a cabin. A target profile containing the sound level in dB of the nine engine orders from C2 to C6 with the half-order interval was pre-designed. Control experiments in real-time were carried out at the neutral mode of an actual car when the engine speed was swept from 1000 to 4800 RPM. Experiment results showed that the performance of the VEM-ASQC algorithm was achieved required sound quality within small errors. Therefore, the VEM-ASQC algorithm can be applied to the practical implementation in a passenger car by reducing the degradation effect due to the distance between the driver's ear and the error microphone. [ABSTRACT FROM AUTHOR]

MARINE terminals, RAILROAD design & construction, RAILROADS, INFRASTRUCTURE (Economics), LITERATURE reviews, HARBORS, and HARBOR management

This article discusses the issue of seaport competitiveness. This is one of the most important issues in port studies. Conducting a port competitiveness analysis focuses on comparing components of port competitiveness for selected ports or terminals. First, a comparative analysis of selected seaports was performed in the article, followed by a detailed analysis of selected terminals in indicated ports. The main purpose of the article is to assess the effect of the new investment in the seaport in the town of Police (the construction of the railway connection with the national network) on its competitive position in relation to seaports in the immediate vicinity. To achieve the assumed goal, the following research methods were used: literature review, documentary method, linear weighting method, and variant analysis. The areas covered by the research study are selective seaports in Zachodniopomorskie Voivodeship (Szczecin, Świnoujście, and Police), Poland. Based on the research studies completed so far, it was shown that connecting a seaport with the national rail network may be a significant factor affecting the port's competitiveness in relation to the ports located in the direct vicinity. [ABSTRACT FROM AUTHOR]

SAND, RAILROAD design & construction, PRESSURE, PRICE deflation, and GRAVITATION

Desert sand is subject to deflation, which during the construction and operation of railways in the sandy desert leads to the filling of the railway track with sand and erosion of subgrade. To prevent this phenomenon, the surface of the sand is fixed with a binder, which is sprayed onto a deflated surface. The penetration of the working composition of the binder due to the characteristics of grinding is accompanied by an uneven distribution of the substance, which is proposed to characterize the saturation coefficient. Peculiarities of the interaction of the binder and sand from which the protective crust is formed are revealed, which made it possible to change the nature of the impregnation. Pre-wetting allows to reduce the pore space of sand, change the nature of the transfer of the substance when impregnated into the capillary, and increase the uniformity of impregnation, which as a result allows to obtain a resource-saving solution when fixing the movement of sand. [ABSTRACT FROM AUTHOR]