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ObjectivesRegional medical coordination is essential for health-system reform in Japan, and the quality of healthcare at the regional level is of great interest. Regional differences in the quality of healthcare for cardiovascular diseases have been pointed out in previous research, and we aimed to clarify regional factors that influence the quality.DesignInsurance claims database study.SettingPatients of acute care in Japan.ParticipantsJapanese patients included in the national Diagnosis Procedure Combination (DPC) databases who admitted to hospitals with diagnosis of acute myocardial infarction (AMI) from April 2016 to March 2019.Main outcome and measuresUsing the national DPC databases, risk-adjusted mortality (RAM) in each secondary medical area (SMA) was derived as an indicator for the quality of the healthcare for patients with AMI. Factors associated with RAM were analysed using the partial least squares (PLS) regression model.ResultsThere is a wide variation in RAM in the SMAs; the maximum value was 0.593 and the minimum value was 1.445. The PLS regression identified two components positively correlated with RAM. The first component (Component 1) positively correlates with the proportion of the elderly within the population and negatively correlates with the number of medical facilities per area, the population density, and the intra-SMA access to centres with a high volume of emergency percutaneous coronary interventions (ePCI). The second component (Component 2) positively correlates with the number of medical facilities per area and negatively correlates with the number of physicians per person and the intra-SMA access to centres with a high volume of ePCI.ConclusionThere was wide regional variation in the quality of in-hospital AMI treatments. Results suggested the degree of rurality, the sufficiency of medical resources, the access to high-volume ePCI centres, and coordination of healthcare delivery were associated with healthcare quality for AMI patients.

Aims: Declines in cardiovascular diseases during the first surge of coronavirus disease 2019 (COVID-19) have been reported. With the repeating surges of COVID-19, we aim to investigate the medium-term impact of the COVID-19 pandemic on the practice of percutaneous coronary interventions (PCIs). Methods: We performed a descriptive analysis of rates of PCIs, utilizing administrative data in Japan. Changes in the proportion of severe cases and in-hospital mortality since the start of the COVID-19 pandemic were investigated using interrupted time series (ITS) analyses. Results: From April 2018 to February 2021, 38, 696 and 28, 585 cases of elective and emergency PCIs, respectively, were identified. The rates of PCIs decreased during the first and third COVID-19 surges. The ratios of monthly rates of elective PCIs to that in the corresponding months during the previous 2 years were 50.3% in May 2020 and 76.1% in January 2021. The decrease in rates of emergency PCIs was smaller than that of elective PCIs. The ITS analyses did not identify any significant changes in the proportion of severe cases and in-hospital mortality. Conclusions: We found that the impacts of COVID-19 on PCIs were larger in the first surge than in the subsequent and larger in the elective than in the emergency; this continued over the medium-term. During the COVID-19 pandemic, in-hospital mortality of cases undertaking emergency PCIs did not change.

Coping with emergency situations requires effective and prompt decision-making under constantly changing situations. The deployment of various kinds of sensors makes it possible to acquire vast amounts of information. At present, however, most information processing is not automated; therefore, the quality of decision-making depends heavily on the capacities of the decision maker. To solve this problem, we propose a system for predicting future situations through parallel simulations based on observation data. To facilitate the development of such systems, we have been developing an optimistic simulation engine (hereafter referred to as O-SE) that supports parallel simulation of many possible situations and dynamic simulation modification based on observation data acquired by sensors. The design and evaluation results of the O-SE are illustrated in this paper.

We investigated the possibility of efficiently reclaiming fumed silica slurry in an oxide chemical-mechanical polishing (CMP) process in order to reduce the cost of consumables. We demonstrated the feasibility of reclaiming condensed waste slurry for reuse. The reclaimed slurry had a ten-fold increase in number of particles larger than 0.56 μm over the original slurry. However, there was significant decrease in the number of particles larger than 1.01μm in the reclaimed slurry compared with that in the original one because depth filters used during reclamation effectively remove agglomerated particles and foreign materials from the condensed waste slurry. The removal rate and uniformity of the reclaimed slurry was comparable with original one. Even though there was a slight increase in particles on the wafers, no changes in level of micro-scratches on wafers was observed. Therefore, the CMP performance of the reclaimed slurry is comparable to that of the original one.

The bathymetric changes and changes in longshore sand transport passing through the tip of the headland were investigated using the contour-line-change model, while changing the shape and scale of the artificial headland. The maximum shoreline recession and eroded area downcoast of the headland, and rate of decrease in longshore sand transport were compared each other. It is concluded that the groin part of the headland must be extended first to reduce longshore sand transport off the artificial headland.

In Lake Kasumigaura, lakeshore vegetations and sandy beach have been devastated in recent years. To recover the sandy beach in Okisu Area in this lake, beach nourishment has been planned with coastal facilities to stabilize the beach, such as groins, detached breakwaters, artificial reefs and artificial headlands. To evaluate the effect of these facilities, BGmodel proposed by Serizawa et al.(2006) was applied for predicting the three dimensional topographic changes after the nourishment. It is concluded that the most appropriate method is to stabilize the beach using a headland.

Dynamic similarity of beach changes due to longshore transport was investigated. A relation that longshore sand transport is proportional to hc5/2, where hc is a closure depth, is introduced to derive time scale of beach changes:[t2]/[t1] is given by [l2] 2/[l1] 2.[hcl] 3/2/[hc2] 3/2, where subscripts 1 and 2 show the prototype and model, and 1 is the length scale. Effectiveness of this relation is tested by using the data sets of beach changes measured near the Katakai fishing port as a prototype and those on Odaiba beach as a model beach. Considerably good agreement was obtained.

Beach and dune changes on the Katano and Shioya coasts in Ishikawa Prefecture were investigated by comparison of aerial photographs and field observation. In this area, sand dune develops along the shoreline and main sediment source is the Daishoji River flowing into the central part of the coastline. The shoreline change shows recession on the west side of the river mouth, whereas the shoreline advances on the east side. The mechanism of shoreline changes was explained by the reasons that the eastward energy flux is bigger than the westward flux on this coast, and the intermittent sediment transport was induced by the eastward transport as an oneway transport by the weir effect of the river mouth jetties.

Field observation of the Manly Beach in the suburb of Sydney in Australia was carried out to investigate coastal zone environment. Coastal zone in this area has a much better environment compared with the Japanese coast, much of which is covered artificially by concrete blocks. One of the utilizations, which is new in Japan, is the natural pool built at the corner of the pocket beach. This is a good idea in order to create safe, natural recreational zone for swimming and it may be introduced in Japan. Improvement method in building gently sloping revetment is discussed.

Theoretical solution of shoreline change was applied to the Kujukuri, Misawa and Fuji coasts, and the coefficient of littoral drift was evaluated and compared. Aerial photographs were read to investigate shoreline changes on the updrift side of Katakai fishery port on the Kujukuri coast, where southward littoral drift dominates. Observed shoreline changes were well explained by the theoretical solution. The same method was applied to the Misawa and Fuji coasts, and coefficient of littoral drift on each coast was compared.

Numerical simulation method by applying wave ray theory was developed to predict wave field on the complex seabed topography. The distribution of wave height and wave direction around the shoal of spherical surface was predicted. The results were compared with the predicted distributions by parabolic model. Both results agreed considerably well.

Shoreline changes around Misawa fishing harbor facing the Pacific Ocean in Aomori Prefecture were analyzed through the comparison of aerial photographs taken between 1966 and 1997. On this coast, northward longshore sand transport dominates and construction of harbor breakwaters caused beach erosion on the north side and accretion on the south side of the harbor due to the obstruction of continuous sand movement. Since sand source disappeared on further south coast, sand bypassing from south to north coast of the harbor became impossible. Instead, sand recycle from inside the harbor to the south coast is required with suitable facilities to form a stable beach.

Beach changes triggered by the construction of detached breakwaters near the end of a pocket beach were investigated at the Tojo coast in Kamogawa City in Chiba Prefecture. This beach has an around 3.9km long stretch and is facing the Pacific Ocean. Shoreline changes were read from the aerial photographs and field observation was carried out. Sand accumulated behind detached breakwaters thanks to their wave dissipation effect. Simultaneously this caused beach erosion in the other area and countermeasures were needed to protect facilities. The cause is due to the lack of thinking on overall balance of sandy beach in a closed system of littoral drift. It is concluded that construction of offshore breakwaters in a pocket beach should be carefully done because of the impact to the surrounding coast.

Optimum conditions for surf-riding was investigated. They are given by not only wave characteristicsand sea bottom slope, but also wind condition determining roughness of sea surface. Disappearance of past famous surf spot due to the construction of coastal structures was investigated on the Maebara beach in Kamogawa City in Chiba Prefecture by the comparison of past aerial photographs before and after the construction of structures. Surf spot can be recognized by existence of the triangular-shape surf zone as given by the previous study.

In the university education, acquirement of the proper judging ability of the adequate natural and social systems on the basis of the enough knowledge and philosophy is important. Artificial beach in the city is an adequate site for education to realize techniques to create artificial environment. A trial of field education for undergraduate students in multi-disciplinary sciences was conducted in Odaiba Park in Tokyo Port. Students carried out field observation and beach survey by themselves as well as analysis of beach materials. Conditions of this artificial beach were compared with that of natural beaches. Various issues associated with planning of the beach park were discussed through the young users' eyes.

We have already proposed DTSS (event aware Dynamic Time Step Synchronization method) for speeding up moving objects (MOs) simulation, e.g. aircraft, ships, vehicles and so on, and evaluated it on the HLA (High Level Architecture, IEEE1516) computer cluster environment. However, speeding up the simulation for a number of MOs on a single processor is required as well, when the size of the problem is increased. In this paper, we propose DTSS- RT (DTSS for Road Traffic simulation) that can speed up the simulation by reducing the simulation cost of each MO and the synchronization cost between MOs without degrading simulation accuracy. For evaluating DTSS-RT, we employed a road traffic sub-simulator of RoboCup rescue simulation. The results show that the performance of the simulation based on DTSS-RT is improved approximately 2 to 3 times over that of the conventional method except when the situation includes a heavy traffic jam.

We have already proposed DTSS (event aware dynamic time step synchronization method) for speeding up moving objects (MOs) simulation, e.g. aircraft, ships, vehicles and so on, in a computer cluster environment. However, speeding up the simulation for a number of MOs on a single processor is required as well, when the problem size is enlarged. In this paper, we propose DTSS-RT (DTSS for road traffic simulation), which can speed up the simulation by reducing the simulation cost of each MO and synchronization cost between MOs without degrading the simulation accuracy. For evaluating DTSS-RT, we employed a road traffic sub-simulator of RoboCup rescue simulation. The results show that the performance of the simulation based on DTSS-RT is improved approximately 2 - 3 times over that of the conventional method except when the situation includes a heavy traffic jam.

This paper describes the R&D status of eRTI 1.3, the implementation of the principal functions of the High Level Architecture Run Time Infrastructure (HLA-RTI) interface specification 1.3 (IEEE 1516.1P) and its applicability to large scale distributed cooperative processing systems (DCOPS). In order to achieve flexibility and expandability for supporting DCOPS, standardized system architecture and interface to interconnect heterogeneous systems are mandatory. While the HLA is designed for providing the way to satisfy the above objective particularly for distributed simulation systems (DSS), its architecture and methodology are quite useful also for DCOPS. We propose a DCOPS/HLA system architecture which utilizes HLA as a communication infrastructure for DCOPS. The system architecture of DCOPS and DSS are very similar from the RTI software design viewpoint. If we can show that the functions provided by the HLA are sufficient, and that the performance of infrastructure software is practical, HLA can be applied to DCOPS. We focus on performance issues. We first give an overview of the DCOPS/HLA architecture and our latest version of eRTI 1.3, then show the results of performance evaluation compared with the DMSO's (Defense Modeling and Simulation Office) RTI. The results indicate the upper bound of the communication frequency among agents and subsystems when DCOPS is implemented on the HLA.

The elongation and merging of bay mouth sand spits due to waves were numerically simulated using the BG model (a three-dimensional model for predicting beach changes based on Bagnold’s concept). A bay separated by sandy headlands on both sides was assumed, and the topographic changes were predicted by the model. The wave-sheltering effect of the sand spit located offshore of the other sand spit played an important role in the mergence of the sand spits. The predicted results for the formation of sand spits were in good agreement with those given by Zenkovich (1967).

A groin or a detached breakwater was installed at a cuspate foreland formed on a coast with an abrupt change in coastline orientation and the effect of obstructing longshore sand transport was investigated. The results of the experiment were reproduced using the BG model (a 3-D model for predicting beach changes based on Bagnold’s concept). The beach changes around the structures installed at the cuspate foreland were successfully predicted and the experimental and numerical results were in good agreement. The differences between the effects of the groin and detached breakwater in controlling longshore sand transport and the offshore sand discharge caused by constructing such coastal structures on a steep coast were successfully explained.

In the Ukishima region of Lake Kasumigaura, beach nourishment along with the construction of groins has been carried out to recover a sandy beach. After the beach nourishment, part of the nourishment sand was transported away from the beach, turning around the tip of the downcoast groin owing to the oblique wave incidence in winter. To enhance the stability of the beach, the groins were extended and a spur dike was constructed. To design these structures, a numerical simulation using the BG model was carried out, and the optimum shapes were determined by taking into account the seasonally changing wave direction. The effectiveness of the spur dike was numerically evaluated using the BG model.

Beach nourishment was carried out in the Ukishima region in Lake Kasumigaura to recover a sand beach. A spur dike extending in the direction of predominant waves from NW was attached to the existing groins to prevent the nourishment sand from flowing out at the downdrift end of the groin. After the beach nourishment, aerial photographs had been taken to investigate the shoreline changes and the monitoring surveys such as the bathymetric surveys and sampling of the lakebed material were carried out. It was confirmed that a dynamically stable beach was successfully formed by the construction of spur dike. Sand, the grain size of which is smaller than 0.35 mm, was transported into the zone deeper than Y.P.+0.2 m due to the sorting effect of waves.

Optical power transmission of 5‐μm band CO laser beam through As2S3 glass core Teflon fluorinated ethylene propylene clad fibers is described. The maximum transmitted power is as high as 62 W with a 700‐μm core diameter fiber, which corresponds to a power intensity of 16 kW/cm2 at the fiber output end. The influence of fiber bending on the transmission characteristics is also reported.