Lines In Japan Research Articles

Evaluation of a Dynamic Lane Assignment on Urban Freeways by Using a Microscopic Traffic Flow Simulation

At a merging section of freeways, the mainline traffic flow conflicts with the traffic flow from an onramp, which often causes traffic congestion. To mitigate this conflict, it is important to dynamically manage the lane utilization on the mainline at bottleneck points. Recently, connected and automated vehicles (CAVs) are expected to be widely used on freeways. Guiding CAVs to change lane to avoid conflicts with merging vehicles may alleviate traffic congestion. In this paper, we propose a novel dynamic lane guidance system that can dynamically manage the lane changes in the merging sections with urban freeway ramps. In the proposed system, CAVs are guided to change lane at the lanes upstream of bottlenecks according to traffic conditions, which are detected by the following two methods: 1) cross-sectional vehicle speed information obtained from traffic detectors and 2) vehicle speed information obtained from driving trajectories based on probe data. Then, the effectiveness of the proposed dynamic lane guidance system is evaluated by a microscopic traffic simulator, Vissim, which is calibrated to reproduce the observed traffic states based on full vehicle trajectory data collected at the section near the Tsukamoto merge area on the Hanshin Expressway Route 11 Ikeda Line in Japan. As a result, the obtained results showed that dynamic lane guidance is effective in reducing overall travel time, thus demonstrating the usefulness of dynamic lane guidance. It was also found that traffic control based on partial vehicle information, such as probe data, is sufficiently effective.

Real world data of systemic therapy for hepatocellular carcinoma in Japan: HERITAGE study.

510 Background: Currently 6 regimens are available for advanced hepatocellular carcinoma (HCC) in Japan, including atezolizumab plus bevacizumab (AB), sorafenib (S), and lenvatinib (L) for first-line treatment and regorafenib (R), ramucirumab (RAM), and cabozantinib (C) for the second-line treatment. In real-world clinical practice, the number of combinations of treatment sequences is enormous. We have launched a nationwide registry of systemic therapy for HCC named Hepatoma Registry of Integrating and Aggregating Electric Health Records (HERITAGE). Methods: The HERITAGE is linked to the nationwide follow-up survey of the Japan Liver Cancer Association; cases treated with systemic therapy between 2015 and 2022 were included in the current study. Information on treatment efficacy and duration was collected and registered on each treatment regimen. Results: As of June 2022, 6,400 treatment lines (S 2,319, L 2559, AB 768, R 406, RAM 251, C 71) in 4,307 cases were enrolled. The response rates, disease control rates, and median treatment duration of each sequence of regimens are shown in the table. The 1st line regimen, S, L, and AB, were also used as the second and later lines in Japan and found as effective as if used as the 1st line treatment. Limitation: No adjustments for clinical conditions were performed. Conclusions: We have demonstrated the efficacy of various treatment sequences in a sufficient number of cases. Clinical trial information: UMIN000046567 . [Table: see text]

A Search for Tick-Associated, Bronnoya-like Virus Spillover into Sheep.

Tick-borne diseases are responsible for many vector-borne diseases within Europe. Recently, novel viruses belonging to a new viral family of the order Bunyavirales were discovered in numerous tick species. In this study, we used metatranscriptomics to detect the virome, including novel viruses, associated with Ixodes ricinus collected from Romania and France. A bunyavirus-like virus related to the Bronnoya virus was identified for the first time in these regions. It presents a high level of amino-acid conservation with Bronnoya-related viruses identified in I. ricinus ticks from Norway and Croatia and with the Ixodes scapularis bunyavirus isolated from a tick cell line in Japan in 2014. Phylogenetic analyses revealed that the Bronnoya viruses' sub-clade is distinct from several Bunyavirales families, suggesting that it could constitute a novel family within the order. To determine if Bronnoya viruses could constitute novel tick-borne arboviruses, a Luciferase immunoprecipitation assay for detecting antibodies in the viral glycoprotein of the Romanian Bronnoya virus was used to screen sera from small ruminants exposed to tick bites. No positive serum was detected, suggesting that this virus is probably not able to infect small ruminants. This study represents the first serological investigation of mammalian infections with a Bronnoya-like virus and an initial step in the identification of potential new emergences of tick-borne arboviruses.

Response of a Surge Arrester With a Series Gap for 6.6-kV Distribution Lines to Steep-Front Transients

Surge arresters with a series gap are commonly installed in distribution lines to effectively protect insulators, transformers, and other equipment from lightning threats in Japan. On the other hand, it has been well known that the high-altitude electromagnetic pulse (HEMP) at an early stage, called E1 HEMP, may extensively cause overvoltage on distribution lines, and the rise time of the E1 HEMP is as short as a few nanoseconds, which is much shorter than that of lightning electromagnetic pulses. To evaluate the effectiveness of surge arresters with a series gap against overvoltage induced by the E1 HEMP, it is necessary to evaluate the effect of a discharge delay due to the series gap on the protection level of surge arresters for steep-front transients. In this work, using a pulse current injection system, we apply a high voltage to a surge arrester with a series gap widely used for 6.6-kV distribution lines in Japan and measure the response of the surge arrester to steep-front transients. From the measured results, we obtain the voltage–time characteristics of the surge arrester with a series gap and residual voltages, which are compared with the results for lightning impulse voltage.

Completion of the First ITER TF Coil in the Second Manufacturing Line in Japan

In Japan, 9 ITER TF coils for Japan and 10 TF coil cases (CCs) for EU are procured from two suppliers. In the second manufacturing line (ML), some of manufacturing procedures were optimized and/or rationalized from lessons learned from the experiences in the first ML. These efforts contributed to simplification and acceleration of the fabrication of the ITER TF coil in the second ML and then, the first ITER TF coil has been completed in May 2021 in the second ML. In addition, the most challenging processes in TF coil fabrication such as very accurate current center line positioning and proper gap between a winding pack (WP) and CC, more than 4 mm were achieved in assembly of WP and CC, as well as the first ML. These results justified the validity of the optimized and rationalized manufacturing procedure in the second ML. Therefore, we can say that manufacturing in both first and second MLs in Japan has become stable. Actually, four and two TF coils have been completed in the first and second MLs in Japan, respectively.

Improved Electrogeometric Model of UHV Transmission Line Based on Long Gap Discharge and Its Application

Based on long air gap discharge test data and lightning return stroke observation data, an improved electrogeometric model (EGM) considering terrain conditions is established and verified to analyze the lightning shielding performance of UHV transmission lines. The striking distance formula is modified as rs = 0.13 (I2 + 40I)0.814. In this paper, the lightning shielding failure rate of three-phase conductors of EHV and UHV transmission lines calculated by the improved EGM model is consistent with the lightning observation data of actual transmission lines in Japan and the scaled lightning discharge simulation experimental results of UHV transmission lines in plains and mountainous areas of China, which verifies the applicability of the improved EGM model to evaluate the lightning shielding performance of large-scale UHV transmission lines. The improved EGM model is applied to evaluate the influence of tower type and slope steepness on the shielding failure tripping rate of UHV transmission lines. The shielding failure tripping rate of the SZ322 tower is higher than that of the SZT1 tower, and the shielding failure tripping rate of UHV transmission lines is greatly affected by slope gradient and increases with the increase of slope gradient.

Inter-metropolitan regional migration galvanized by high-speed rail: A simulation analysis of the Linear Chuo Shinkansen line in Japan

The development of transportation infrastructure impacts migration, production, and other economic activities along with it. In this study, we conducted a multiregional computable general equilibrium simulation analysis to assess the effects that the proposed 2027 high-speed railway, the Linear Chuo Shinkansen in Japan, will have on population migration. The 47 prefectures ordained by the Japanese administrative unit were considered, and the simulation potential workforce population was taken as 110 million. The population is concentrated in the Tokyo metropolitan area. As per our simulation, once the proposed high-speed railway opens, “travel costs” (comprising time and the monetary costs of traveling) will decrease. This situation will stimulate economic activities and lead people to migrate to the prefectures where the economic environment improves. The results show that this development will ease extreme population concentration while simultaneously increasing employment and production values. However, additional analysis indicates that further development of the Linear Shinkansen to strengthen the current high-speed rail on the route to Tokaido will increase population concentration.

Urban Esthetic Benefits of Undergrounding Utility Lines in Consideration of the Three-Dimensional Landscape

Since the relative weight of form to function has been increasing in urban planning, from the esthetic viewpoint, many cities in the world have been actively pursuing the undergrounding of overhead utility lines. Esthetic factors are urban externalities in the sense that they are not directly traded in markets. Therefore, we need to control them optimally based on their benefits. In this study, we appraise the benefits of undergrounding utility lines in Japan and clarify the dependency of the residents’ willingness to pay (WTP) on the road width and building height. Our results show that the WTP for undergrounding utility lines is lower as the road becomes wider and the buildings along the road become higher. However, when the road is wide, the WTP does not change much regardless of the height of the buildings. In addition, the average value of the benefit–cost ratios of previous undergrounding projects is from approximately 2.27 to 2.65. However, 3–17% of these projects have benefit–cost ratios of less than 1.

Field observation of galloping on four-bundled conductors and verification of countermeasure effect of loose spacers

This paper describes the galloping occurrence conditions of four-bundled conductors and the galloping suppression effect of diagonally arranged loose spacers, which is a type of spacer applicable for four-bundled conductors with two rotational clamps placed at diagonal positions. Field observations were conducted at a full-scale test line in Japan where in-cloud icing frequently occurs. A total of 40 ice accretion events were observed across four winter seasons, and galloping data were obtained in a non-countermeasure phase set with normal spacers and a countermeasure phase set with loose spacers. The relationship between the total displacement amplitude and tension variation was determined to identify the conditions under which large galloping occurred based on tension data, in addition to the displacement data. Galloping was found to occur at wind speeds exceeding 9 m/s, and large galloping oscillations were observed when a certain relationship was satisfied between the wind speed and the amount of ice accretion. Furthermore, it was observed that the loose spacers reduced the galloping oscillation amplitude by approximately 40%. The rotational clamps operated normally under severe natural conditions, and the suppression effect was caused by the difference in the ice accretion characteristics of the rotatable subconductors owing to their rotation.

Full-scale laboratory testing of a geosynthetically reinforced soil railway structure

Railway lines typically use traditional sloping embankments as the principal means of track support. However, the use of Geosynthetically Reinforced Soil (GRS) systems have gained popularity as alternatives to conventional embankments, particularly for high-speed lines in Japan. This system requires less ground stabilization/improvement and less land take than conventional embankments due to its smaller base area. This research investigates the immediate and long-term settlement behaviour of a Geosynthetically Reinforced Soil with Retaining Wall (GRS-RW) system subject to cyclic loading for two track forms: a concrete slab track and a ballasted track. First, a three-sleeper concrete slab section is constructed at full-scale under controlled laboratory conditions, followed by a ballasted track. Both are supported on a 1.2 m deep subgrade and a frost protection layer in accordance with railway design standards. Two different axle load magnitudes are applied statically, and then cyclically/dynamically, using 6 actuators to replicate moving train axle loads. It is observed that the slab track performs significantly better in terms of elastic and plastic deformation under both static and cyclic loading. Overall, the amplitude of the rail displacement under an individual cycle loading was approximately 25% lower for the slab track and the amplitude of the sleeper displacement on the ballasted track was approximately 6–7 times higher.

Topological network and GIS approach to modeling earthquake risk of infrastructure systems: A case study in Japan

In this study, we propose a network-geographic information system (GIS) modeling framework to construct a risk map for revealing infrastructure vulnerability to seismic hazards. The framework considers the cascading network of interdependencies among the effects and intermediate effects of earthquakes. Network modeling is applied to analyze infrastructure vulnerabilities and identify the infrastructure types that are vulnerable to earthquakes, while geographical modeling is applied to identify seismic hazards in terms of ground motion intensity and earthquake source faults. Reported earthquake cases in Japan are selected for analysis, and an illustrative example of the modeling of a risk map is conducted on a section of a conventional train line in Japan. In the network modeling, statistics and network diagrams are developed to analyze the relational earthquake incident data. The results demonstrate that earthquakes can cause direct and indirect effects on infrastructure, and interdependencies can be found among the effects and intermediate effects. In the geographical modeling, probabilistic distribution is adopted to predict the seismic characteristics; the results reveal the intensity occurrence probability and cascading consequences of different earthquake intensities, and predict specific degrees of destruction. Infrastructure vulnerability and seismic hazard maps are developed according to the analyzed results. A risk map is then constructed by integrating the infrastructure vulnerability map with the seismic hazard map. This study characterizes the risk of earthquakes to infrastructures, capturing the complex interdependencies to reveal the cascading effects from earthquakes, and quantifying and demonstrating infrastructure areas vulnerable to seismic hazards.

Contributing Factors for Delays during the Morning Commute Hours and the Impact of the Spread of COVID-19 for Metropolitan Train Lines in Japan

The present study aims to conduct 2 types of statistical analysis to reveal the impact of the spread of COVID-19 on train delays by comparing the potential contributing factors before, during and after the outbreak of the virus in the metropolitan train lines in Japan. First of all, the result of the present study clearly revealed the changes in contributing factors for train delays caused by the spread of COVID-19. Specifically, the contributing factors for train delays changed due to the decrease of passengers by the effect of the outbreak of the virus. Additionally, though large terminal stations were considered to be a major contributing factor in causing and increasing train delays in the past, this was not the case after the spread of COVID-19. Therefore, under such conditions, it is more effective to make improvements in small to medium stations and tracks rather than terminal stations. Furthermore, as the decrease in passengers also decreased train delays in commuter lines going to the suburbs due to the spread of COVID-19, the contributing factor for such lines is the excessive number of passengers. Therefore, as for countermeasures for train delays after the effects of COVID-19, it is necessary to disperse passengers in order to avoid passengers concentrating in the same time zones and train lines.

Verification of Superconducting Feeder Cable in Pulse Current and Notch Operation on Railway Vehicles

Railway transportation is of safety, convenience, economy, and environmental friendliness. However, with energy issues becoming increasingly important in this century, it is important to assess the situation in the transportation sector. When the superconducting cable is used as a feeder of the railway electrification system, the voltage drop can be significantly reduced. Therefore, the superconducting feeder has many effects, for example, the reduction transmission losses, the improvement of the regeneration factor, and the reduction of substations. We designed superconducting feeder and introduced to the Izuhakone Railway Sunzu line in Japan. After the system was checked from the aspect of cooling and current properties, the train running test was conducted. From the result of switching notch tests, it was found that the current flows continuously via the superconducting cable according to the notch operation. Furthermore, to inspect the influence of superconducting material, a large pulse current test was performed using the transmission equipment of a railway. It can be confirmed that superconductor can be used as railway feeder because the materials can cope with the current change peculiar to railway required for practical use.

Benefits of Undergrounding Utility Lines in Consideration of the Three-Dimensional Urban Landscape

We appraise the benefits of undergrounding utility lines in Japan and clarify the effects of road width and building height. Our results show that the willingness to pay (WTP) for undergrounding utility lines is lower as the road becomes wider and the buildings along the road become higher. However, when the road is wide, the WTP does not change much regardless of the height of the buildings. In addition, the average value of the benefit-cost ratios of previous undergrounding projects is approximately 2.27 to 2.65. However, 3-17% of these projects have benefit-cost ratios of less than 1. This indicates that we should perform cost-benefit analyses for future undergrounding projects.

Fault Ride-Through Characteristics of Small Wind Turbines

There is significant potential for an increase in the use of kilowatt-class small wind turbines (SWTs) in Japan due to reduced limitations with respect to installation, despite their high cost. At this stage, the Japanese grid code has not been considered sufficiently with respect to grid-connected SWTs, and the addition of fault ride-through (FRT) requirements for SWTs has been requested. Moreover, the FRT of SWTs is challenging to achieve owing to the low inertia constants when compared with those of large-scale wind turbines, which result in significant acceleration of the rotor speed and an increase in the input voltage of the power conditioning system (PCS) during FRT operation. In this study, FRT field tests were conducted on SWT systems against a voltage dip with a duration of ~1 s, and it was confirmed that the SWT systems satisfied the FRT requirements for photovoltaic (PV) systems connected to low-voltage distribution lines in Japan. The behaviors of the rotational speed of the SWTs and the PCS input voltage in an FRT operation were then analyzed, and it was noted that the increase in the PCS input voltage with the overspeed of the turbine can reach the upper limit and make the PCS cease operation, which indicates failure of the FRT. The overvoltage, therefore, requires restriction using a method such as pitch control, furling, and electrical and/or mechanical brakes.

Train Running Test Transmitted by Superconducting Feeder Cable and Study as an Example of Line in Japan and France

Aiming to achieve a superconducting feeder cable system applicable to Japan, France, and other countries, we summarize the required specifications created for prototyping of superconducting cables. Superconducting cables manufactured based on the required specifications were subjected to voltage, current, and other tests and then verification tests using train. The above mentioned test results have given us good prospects for superconducting feeder cables that can be applied to actual lines in Japan and France. Simulation was conducted to check the effect of these superconducting cables in actual lines. Analysis results were obtained to confirm that the introduction of a 310-m superconducting cable had an effect of compensating for voltage drops.

Condition Monitoring of Railway Tracks from Car-Body Vibration Using a Machine Learning Technique

A track condition monitoring system that uses a compact on-board sensing device has been developed and applied for track condition monitoring of regional railway lines in Japan. Monitoring examples show that the system is effective for regional railway operators. A classifier for track faults has been developed to detect track fault automatically. Simulation studies using SIMPACK and field tests were carried out to detect and isolate the track faults from car-body vibration. The results show that the feature of track faults is extracted from car-body vibration and classified from proposed feature space using machine learning techniques.

Production Networks, Geography, and Firm Performance

This paper examines the importance of buyer-supplier relationships, geography and the structure of the production network in firm performance. We develop a simple model where firms can outsource tasks and search for suppliers in different locations. Low search and outsourcing costs lead firms to search more and find better suppliers. This in turn drives down the firm's marginal production costs. We test the theory by exploiting the opening of a high-speed (Shinkansen) train line in Japan which lowered the cost of passenger travel but left shipping costs unchanged. Using an exhaustive dataset on firms' buyer-seller linkages, we find significant improvements in firm performance as well as creation of new buyer-seller links, consistent with the model.

Genome-wide association mapping of fruit-quality traits using genotyping-by-sequencing approach in citrus landraces, modern cultivars, and breeding lines in Japan

Association mapping is an attractive method to identify QTLs in perennial horticultural crops such as citrus, as it does not need a designed cross between parental genotypes and can save time and labor to construct a segregating population. It usually requires more genetic markers than linkage-based QTL mapping owing to a lower degree of linkage disequilibrium (LD). However, recent advances in next-generation sequencing offer high-throughput, cost-effective methods, including genotyping-by-sequencing (GBS), for genotyping massive amounts of single nucleotide polymorphisms (SNPs). In this study, we performed a genome-wide association study (GWAS) of fruit-quality traits in citrus using SNPs obtained by GBS. We evaluated 110 citrus accessions, including landraces, modern cultivars, and breeding lines, for eight fruit-quality traits (fruit weight, fruit skin color, fruit surface texture, peelability, pulp firmness, segment firmness, sugar content, and acid content) during 2005 to 2012 (except 2007). GBS found 2309 SNPs, which we anchored to the clementine reference genome. We evaluated LD in the 110 accessions and confirmed that GBS gave enough SNPs to conduct GWAS. We identified seven QTLs, including four novel ones, comprising four significant QTLs for fruit weight and one QTL each for fruit skin color, pulp firmness, and segment firmness. These QTLs offer promise for use in citrus crossbreeding.

Efficiency Assessment of Transit-Oriented Development by Data Envelopment Analysis: Case Study on the Den-en Toshi Line in Japan

Transit-Oriented Development (TOD) is an urban planning approach that encourages a modal shift from private to public transportation. This shift can generate additional benefits from a sustainability perspective. This study aims to assess the efficiency of TOD by applying the data envelopment analysis (DEA) method. The ridership of public transportation is considered as the direct output characteristic of TOD efficiency, and nine indicators of ridership are selected as inputs on the basis of the core concepts of TOD. These concepts include density, diversity, and design (3Ds). The Tokyu Den-en Toshi Line in Japan is presented as a typical case of TOD because this line includes TOD and non-TOD stations. Assessing and comparing the results of all railway stations reveal that almost all indicator values of non-TOD stations are higher than those of TOD stations. The results suggest that TOD planning and programs are inefficient in terms of ridership generation. This implication, however, may be attributed to the inadequacy of the selected indicators for TOD assessment. The results obtained after adding operation year as input indicators and removing transfer station show that TOD stations perform efficiently and in accordance with expectations. This response indicates that the inclusion of influential factors is necessary for equitable TOD assessment. Therefore, other influential factors must be considered when evaluating the efficiency of TOD-based stations with different inherent attributes. In addition, the design input with the largest impact on all inefficient units was identified, suggesting that management of bus service and railway system should be well enhanced.