Terminal Station Research Articles

Target Localization Based on Intermodulation Feedback for Multisine Wireless Power Transmission Using a Time-Modulated Array

To achieve accurate power feeding to a terminal (e.g. rectenna) in the far-field wireless power transmission (WPT), a new method is proposed to locate the terminal so that the base station can adaptively adjust its beam steering and transmitting power to satisfy the high-efficiency power conversion conditions of the rectifier. In this work, the generated intermodulation (IM) signal at rectenna under multisine incidence is employed to establish the feedback link with the base station. A linear time-modulated array (TMA) is exploited to generate two-tone multisine wave by the optimized modulation sequence thanks to its multi-beam radiation behavior at the base station side. In the terminal end, the IM signal is spontaneously produced due to the nonlinearity of power rectifying under two-tone incidence and employed as the feedback. To highly isolate the two tones and IM signal, a dual linear polarized (DLP) antenna is designed to ensure a compact system design for both sides. By this way, the feedback IM signal carrying the terminal's direction and distance information is sensed by orthogonally polarized antenna pairs. Then the direction of terminal is obtained by the proposed high-accuracy direction of arrival (DoA) estimation method using a multi-baseline TMA, which is realized by a two-stage single-pole-double-throw (SPDT) switching network. Regarding the imperfection of RF switches, a compensation method is proposed. With estimated DoA, the distance between terminal and base station is evaluated based on the received signal strength indicator (RSSI) method. To verify the feedback mechanism, a prototype is fabricated and tested.

Resilience conceptual framework for assessing the performance of transit service

ABSTRACT Traditionally, the performance of transit service has been assessed using the framework of level of service or quality of service. This study proposes a novel platform for evaluating performance in the context of resilience. The term resilience represents the ability of a system to absorb and recover from shocks. The concept is thus useful to monitor the degradation and recovery of transit service. This new model is applied to Seoul Metro Line 7 using frequency as the service attribute that could degrade due to a system shock. An empirical study analysing train operations data assesses the dynamic and disaggregate nature of performance of transit service. This feature is understood to add useful insights to the existing evaluation frameworks because the proposed approach can represent the real and perceived performance of transit service. The performance using this framework is impacted by distance from the terminal stations and time-of-day characteristics. Three issues including the level of demand, the form of indicator, and the time unit of analysis are also discussed. Finally, recommendations for further studies, particularly around the theme of factors affecting the performance of transit service and a comparative analysis between the proposed framework and the conventional approaches involving level of service and quality of service, are presented.

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第１０報）地下街における実測およびCFD解析

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第１０報）地下街における実測およびCFD解析

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第９報）避難時を想定した地下街における滞在睡眠実験

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第９報）避難時を想定した地下街における滞在睡眠実験

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第11報）BCD電源システムと既存地域熱供給システムとの連携の可能性の検討

大災害時におけるターミナル駅周辺地区および地下街のエリア防災対策としてのオフサイトセンターに関する研究 （第11報）BCD電源システムと既存地域熱供給システムとの連携の可能性の検討

Estimation of Origin-Destination Flows of Passenger Cars in 1925 in Old Tokyo City, Japan

In recent years, surveys of personal travel behavior have been conducted around the world and these surveys have been used for understanding the characteristics of people flow. However, it is impossible to acquire people and traffic flows for the modern era (1868–1945). In modern era Japan, some traffic surveys were conducted, and that records still persist. The purpose of this study was to estimate origin-destination (OD) flows in old Tokyo in 1925 based on the historical traffic census record. In this study, OD flows were estimated using an absorbing Markov chain model, which is a simple model based on traffic generation and transition probabilities. Transition probabilities in unobserved nodes were estimated using genetic algorithms (GA). The result of OD distributions is clearly different in the eastern part of Tokyo City, the Shitamachi area, from the western part, the Yamanote area. The traffic was very busy in Shitamachi, an area which included terminal stations and a central business district. In Yamanote, major traffic generation and absorption points were distributed along the main streets to the Shinjuku or Shibuya areas. These results are affected by the distribution of main roads and the locations of residences or workplaces of car owners.

Flexible alarming mechanism of a general GDS deployment for explosive accidents caused by gas leakage

Gas detection system (GDS) is critical for identifying and suppressing the flammable or hazardous gas leaked by incidents. The spread of a flammable gas cloud is susceptible to external factors and highly uncertain, but the GDSs deployed today often raise alarms based on certainty. It means that the threshold value set in a GDS for triggering alarms is a constant. Such an approach sometimes cannot accurately determine the leakage location, and so it may result in a great delay of gas detection. To reduce the risk of gas leakage, this paper proposes a flexible triggering mechanism for GDSs, where an alarm is raised or not depending on the number of sensors whose reading are reaching or closing to the preset threshold. An equivalent gas cloud (EGC) model is introduced here to provide design inputs for such a flexible triggering GDS. The volume and location distribution of an EGC are estimated with the Gaussian dispersion model, based on the changes of wind speed and direction. A case study in a terminal station of LNG is conducted, to illustrate the effectiveness of the new approach. The findings show that the flexible triggering mechanism is able to make alarms of a GDS more accurate, and meanwhile avoiding unnecessary measures, which can effectively optimize alarming thresholds.

Thermal resistance analysis of cryogenic frosting and its effect on performance of LNG ambient air vaporizer

Liquefied natural gas (LNG) ambient air vaporizer (AAV) utilizes renewable energy from ambient air (aerothermal energy) to evaporate LNG in gas terminal stations. Frost may occur on the AAV surface due to cryogenic LNG, leading to poor heat transfer performance. This paper presents a numerical analysis of the thermal resistance of cryogenic frost layer and its effect on the heat transfer coefficient of the air side of AAV. The air temperature near the cryogenic fin tube surface differs from the ambient air and was modified by a three-dimensional integrated model of AAV. An experimental test of the thickness of the frost layer on the AAV fin tube was conducted to validate the numerical model of the frost formation, and the test data agrees well with the numerical results. The results show that a “valley heat transfer coefficient temperature” exists under frost conditions, which is the corresponding air temperature of the minimum heat transfer coefficient of AAV.

Two-echelon Inventory Deploy In Advance Selling

Advance selling has been chosen and accepted by more and more e-commerce companies and consumers, but it’s common for consumers to cancel orders in advance. Compared to spot sales, advance selling owns a longer order delivery time. The purpose of inventory allocation is to meet the economic needs and time preferences of consumers in different situations, to maximize profits and enhance the competitiveness of e-commerce companies. This dissertation dissects the consumer demand in terms of consumer utility and Regret Theory, and it dives into consumer time satisfaction in combination with the delivery time of orders and the expected delivery time of consumers. The dissertation builds a two-echelon inventory allocation model for inventory distribution. By analyzing the model and the example, the following conclusions can be drawn: inventory downward of e-commerce enterprise can significantly improve consumer time satisfaction. The greater inventory-sink of each terminal distribution station, the more satisfied consumers are. Meanwhile, inventory downward cannot be improved by continuing to increase its amount when the time satisfaction reaches a certain level. E-commerce enterprises should adopt different inventory allocation schemes according to diverse purposes.

Research on Shipping Scheme of Express by High-speed Railway Passenger Train

High-speed rail express mainly uses the remaining space of passenger trains for transportation from the originating station to the terminal station. The number of shipments at the intermediate station of the train is small, but the transportation demand at them is also considerable. If the high-speed rail express shipping plan considers the express delivery demand of the intermediate station, it can help the high-speed rail express operation enterprise to increase profits by coordinating the demand of the stations along the global optimal angle. This paper considers the short-term stop time of the high-speed rail, limited train loading space, different timeliness requirements of high-speed rail express products, etc., and establishes the mathematical model of the high-speed rail express shipping scheme. This paper predicts the demand for various products of Beijing-Shanghai high-speed rail express in 2025 and calculate the transportation capacity of B-S HSR. The shipping plan obtained verifies the effectiveness of model.

The Influence of Railways on the Economy of the North East of the Don Host Region (60s – 90s of the 19th Century)

Introduction. The article deals with the issue of the influence of the railways built in the 1860s – 1890s in the northeast of the Don Cossack Host Region on the economic development of this region. Methods. Published reports of railway joint-stock companies and archival statistical materials, observations of contemporaries show that this influence was ambiguous. Analysis and results. Gryaz-Tsaritsyn railway, which passed through the densely populated and fertile areas of Khopyorsky and Ust-Medveditsky districts, had the most positive impact on the economy. As a result, grain and livestock production significantly increased, agricultural marketability increased, old major trade and industry centers (Uryupinskaya stanitsa) were developing and new ones (Mikhaylovka sloboda, Privokzalny khutor) appeared. At the same time, the very first Volga-Don railway was mainly transit and had no noticeable impact on the development of the surrounding area, except for Kalach terminal station. Tsaritsyn- Tikhoretsk and East-Donetsk railways passed through the sparsely populated and infertile margin of the region, far from large settlements. Their influence on the local economy at first was rather negative and led to the collapse of the traditional horse carriage. The old trade centers, Nizhne-Chirskaya stanitsa and Kalach-on-Don khutor, were put in unfavorable conditions, which led to the slowdown in their development and the outflow of goods and traders to Oblivskaya and Morozovskaya railway stations.

Distributed Approximate Dynamic Control for Traffic Management of Busy Railway Networks

Railway operations are prone to disturbances that can rapidly propagate through large networks, causing delays and poor performance. Automated re-scheduling tools have shown the potential to limit such undesirable outcomes. This study presents the network-wide effects of local deployment of an adaptive traffic controller for real-time operations that is built on approximate dynamic programming (ADP). The controller aims to limit train delays by advantageously controlling the sequencing of trains at critical locations. By using an approximation to the optimised value function of dynamic programming that is updated by reinforcement learning techniques, ADP reduces the computational burden substantially. This framework has been established for isolated local control, so here we investigate the effects of distributed deployment. Our ADP controller is interfaced with a microscopic railway traffic simulator to evaluate its effect on a large and dynamic railway system, which controls critical points independently. The proposed approach achieved a reduction in train delays by comparison with First-Come-First-Served control. We also found the improvements to be greater at terminal stations compared to the vicinity of our control areas.

Regularized Zero-Forcing Precoder for Massive MIMO System With Transceiver I/Q Imbalances

In this letter, we propose a downlink precoder for massive multi-input multi-output (MIMO) system in the presence of I/Q imbalance (IQI) at both base station and user terminals (UTs). We formulate a minimum mean-square error (MMSE) precoding problem with multiple regularization parameters for different channel qualities and channel correlations of UTs with different IQIs. Then we obtain the asymptotically optimal precoding matrix for the massive MIMO system. Moreover, we derive the asymptotic sum rate of the proposed regularized zero-forcing (RZF) precoder. We show that the proposed RZF precoder achieves significantly higher sum rate than conventional RZF precoder. In addition, the proposed precoder shows robust performances to severe IQI conditions.

Streetcar Passenger Flow Maps in Old Tokyo City in 1930

Abstract. In recent years, we can easily get various data of human mobility. Based on these data, there are many studies about human mobility all over the world. In Japan, Person Trip (PT) survey has been carried out once a decade after 1960s. With the use of PT data, we can grasp people’s flow, however, it is difficult to get such data in the modern era. In old Tokyo city, some traffic surveys were carried out by municipality. These data are limited, however, it is possible to figure out the people’s flow in the modern era by digitizing and making maps from historical documents of these surveys. The purpose of this study is to make and analyse streetcar passenger flow maps in old Tokyo city by using origin-destination (OD) data acquired through the survey conducted in 1930.We used the OD flow data of the streetcar passenger acquired by old Tokyo city on Tuesday, June 10th, 1930. The study area was in the centre of present Tokyo 23 wards. Although the streetcars no longer exist except for one line at present, there were a lot of routes in the city in 1930. The streetcars were the important transportation for people living inside and outside the city.To make OD flow map, we first made digital data of the OD matrix of the passengers from historical documents of the survey. There were about 400 stops, however, some adjacent stops were aggregated to save space of the document. Therefore, the OD matrix were 289 by 289. In addition, we created GIS data of streetcar’s network based on old maps and historical documents. The aggregated stops were created in a midpoint of original stops. After that, we made the OD flow map by using the visualizing method described by Wood, Dykes, & Slingsby (2010).Figure 1 shows OD flow map of streetcar passenger in 1930. The results of this study are summarized as follows; 1) There were many people who went to the direction of Tokyo station(E6), Nihonbashi(E7), and Ginza(F6) from the entire area of the city. These areas have been a centre of commerce since pre-modern era, being crowded with shoppers, tourists and workers. Particularly, there were many commuters around Tokyo station because it had many office buildings. 2) There were many people who used the terminal stations located outside the city. These stations such as Shinjuku(D1) and Shibuya(G1) have been nodal points of other railways in the western part of Tokyo. This result showed that the people moved to the suburb of Tokyo after the Great Kanto Earthquake in 1923. 3) The movements from the west of the city to the centre of Tokyo were longer than those from the east of the city, because the western area had the restrictive land uses such as high class residential area and military reservation which covered a vast area of the western part of the city. In contrast, the old urban area extended to the eastern part of the city since that era.

Eid homecoming "Mudik" tradition as a conventional pattern in the global era

The tradition of going back to hometown on Eid which called mudik in Bahasa; happens every year and all the time. Mudik at Eid is an interesting phenomenon, because this culture can only be seen in several countries that have Muslim communities, including in Indonesia. The discussion about the phenomenon of Mudik is important because the nuances contain in it can be analyzed from various approaches, including sociology, religion and economic. The purpose of this study is to describe the phenomena of Muslims behavior in the tradition of Mudik. It is done in order to get information in depth through extracting accurate information in the field about Mudik as local wisdom that functions in forming harmony in the social life. The approach of this study used a qualitative approach with survey - descriptive methods, through interview, observation and documentation techniques. This research used purposive sampling technique so the informants were accidentally determined with totally 27 people, located in Garut Bus Terminal and Garut Train Station. The data were analyzed through stages of reduction, display, analysis and conclusion. The result shows that Mudik as local wisdom is still maintained with purpose to establish harmony for the social life as social integration in the global era. Keywords: Eid Homecoming, Conventional Patterns, Social Life

A Terminal-Oriented Distributed Traffic Flow Splitting Strategy for Multi-Service of V2X Networks

With the development and the characteristics of terminal services of the 5G (5th-Generation network) Internet of Vehicles (IoVs), this paper proposes a distributed splitting strategy for multi-type services of 5G V2X (Vehicle to X) networks. Based on a service-oriented adaptive splitting strategy in heterogeneous networks, combined with various service types such as communications between the networks, terminal, and base stations, and the value-added services of 5G IoVs, the proposed strategy jointly considers delay and cost as optimization goals. By analyzing the characteristics of the different services, the proposed traffic flow splitting strategy is modeled as an optimization problem to efficiently split services in 5G V2X networks. The simulation results show that by setting the traffic distribution policy for each service, the distributed traffic flow splitting strategy can significantly improve network transmission efficiency and reduce the service costs in a vehicle V2X network.

Determining the Rational Motion Intensity of Train Traffic Flows on the Railway Corridors with Account for Balance of Expenses on Traction Resources and Cargo Owners

Abstract The article proposes a method for determining the rational motion intensity of specific train traffic flows on railway transport corridors with account for balance of expenses on traction resources and cargo owners. A mathematical model based on stochastic optimization is developed, which allows to optimize, in the conditions of risks, the interval between trailing trains on the railway lines taking into account the limited resources of the traction rolling stock, the capacity of the stations and freight fronts at the cargo destination point. Solving this mathematical model allows to find a balance between the expenses for movement of train traffic flows from different railway lines to their terminal reference station and the expenses of a consignee, subject to the limitations of the technological logistics chain in cargo transportation. For the solution of this mathematical model, a Real-coded Genetic Algorithm (RGA) was used.

High-Mobility Wideband Massive MIMO Communications: Doppler Compensation, Analysis and Scaling Laws

In this paper, we apply angle-domain Doppler compensation for high-mobility wideband massive multi-input multi-output (MIMO) uplink communications. The time-varying multipath channel is considered between high-speed terminal and static base station (BS), where multiple Doppler frequency offsets (DFOs) are associated with distinct angle of departures (AoDs). With the aid of large-scale uniform linear array (ULA) at the transmitter, we design a beamforming network to generate multiple parallel beamforming branches, each transmitting signal pointing to one particular angle. Then, the transmitted signal in each branch will experience only one dominant DFO when passing over the time-varying channel, which can be easily compensated before transmission starts. We theoretically analyze the Doppler spread of the equivalent uplink channel after angle-domain Doppler compensation, which takes into account both the mainlobe and sidelobes of the transmit beam in each branch. It is seen that the channel time-variation can be effectively suppressed if the number of transmit antennas is sufficiently large. Interestingly, the asymptotic scaling law of channel variation is obtained, which shows that the Doppler spread is proportional to the maximum DFO and decreases approximately as $1/\sqrt {M}$ ( $M$ is the number of transmit antennas) when $M$ is sufficiently large. The numerical results are provided to corroborate the proposed scheme.

Features of cellular immunity and regeneration for alcoholic fibrosis of the liver

Purpose. The subpopulation composition of peripheral blood lymphocytes was evaluated in patients with alcoholic liver fibrosis (ALF).Materials and methods. The study included 62 patients with ALF; 15 patients abusing alcohol without liver fibrosis and 20 conditionally healthy donors. In samples of lysed peripheral blood, the number of cells bearing surface markers was determined by flow cytometry. In patients with ALF at terminal stages of fibrosis, significant lymphopenia was recorded with a change in the composition of the main subpopulations of lymphocytes relative to the values of conditionally healthy donors and the comparison group.Results. We identified in the blood of ALF patients with terminal (III–IV) stage (relative to control and comparison group) of the relative number of naive (TN) and central memory T-lymphocytes (TCM) associated with an increase in the number of effector cells (TEM and TEMRA) allows us to suggest in this category of patients the direct differentiation of TN and TCM lymphocytes to effector (TEM and TEMRA), which can aggravate the course of the tissue-destructive process due to the high biocidal activity of the latter. Elevated levels of hematopoietic (CD34 and CD133) cells in the peripheral blood at the initial and moderate stages. (I–II) fibrosis (relative to control and comparison group) may be due to persistent inflammation in the liver parenchyma and an increasing imbalance between the processes of its damage and reparative capabilities. Whereas the decrease in their number at the terminal station fibrosis may indicate an increasing decompensation and depletion of the regenerative potential of the organism in the final stages of the degenerative process.Conclusions. In general, the obtained data demonstrate new aspects of the immune regulation of the processes of fibrogenesis in chronic alcoholism.

The analysis of catchment areas of metro stations using trajectory data generated by dockless shared bikes

The dockless bike-sharing system is getting popular and widely used for connecting with public transportation. This study addresses questions on how the catchment areas of metro stations are influenced by the dockless bike-sharing system and what their characteristics are. We develop methods to process bike trajectories and generate the bike catchment areas of metro stations. The proposed methods are applied to generate the bike catchment areas of the metro stations in Shanghai as a case study. We then conduct analyses to answer our research questions in three aspects. First, we analyze the spatial distribution patterns of the bike catchment areas and determine that the sizes of bike catchment areas increase from the city center to the suburban area. Second, using two indicators, namely coverage ratio and overlap degree, we examine the impact of dockless bike sharing on the catchment areas as compared with 800 m pedestrian catchment areas. As a resut, the catchment coverage ratio of the central city is increased by 104% and the maximum overlap degree increases from five to nine stations. Third, we apply regression models to explore the factors associated with the sizes of the bike catchment areas. The results show that the sizes of the bike catchment areas are positively associated with good metro service, frequent morning trips, diverse users, and large distances to the city center and terminal stations, but negatively associated with the density of metro stations. Based on the analytical results, we outline the application potentials and implications for relevant planning.