Search NASA⌕ Search

SEARCH · Search NASA

Results for “JAPAN”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2

Investigation from Japanese MAGSAT Team. Part A. Crustal structure near Japan and in Antarctic station. Part B. Electric currents and hydromagnetic waves in the ionosphere and the magnetosphere

Preliminary results of MAGSAT data analysis are described. Regional anomaly maps (deviations from the MGST model field) for X,Y,Z, and F in the area of 115 to 155 deg E and 20 to 60 deg N were obtained. A similar map for the geomagnetic total force anomaly in the vicinity of Japan showed that the observed anomaly can be explained by the difference in crustal magnetization between the Japan Sea and the Japan Island, which reflects a difference of 25 km in the thickness of the magnetized layer. The MAGSAT record of a sudden commencement of a magnetic storm above the South Atlantic Ocean showed a reverse impulse particularly in the D-component. Results relating to toroidal currents in the ionosphere, transverse and parallel perturbations over the polar regions, the relationship between field aligned currents and precipitating electrons, and the calculation of the subsatellite electric field are also discussed.

Fukushima, N.↗

Insights into software development in Japan

The interdependence of the U.S.-Japanese economies makes it imperative that we in the United States understand how business and technology developments take place in Japan. We can gain insight into these developments in software engineering by studying the context in which Japanese software is developed, the practices that are used, the problems encountered, the setting surrounding these problems, and the resolution of these problems. Context includes the technological and sociological characteristics of the software development environment, the software processes applied, personnel involved in the development process, and the corporate and social culture surrounding the development. Presented in this paper is a summary of results of a study that addresses these issues. Data for this study was collected during a three month visit to Japan where the author interviewed 20 software managers representing nine companies involved in developing software in Japan. These data are compared to similar data from the United States in which 12 managers from five companies were interviewed.

Duvall, Lorraine M.↗

Space robotics in Japan

Japan has been one of the most successful countries in the world in the realm of terrestrial robot applications. The panel found that Japan has in place a broad base of robotics research and development, ranging from components to working systems for manufacturing, construction, and human service industries. From this base, Japan looks to the use of robotics in space applications and has funded work in space robotics since the mid-1980's. The Japanese are focusing on a clear image of what they hope to achieve through three objectives for the 1990's: developing long-reach manipulation for tending experiments on Space Station Freedom, capturing satellites using a free-flying manipulator, and surveying part of the moon with a mobile robot. This focus and a sound robotics infrastructure is enabling the young Japanese space program to develop relevant systems for extraterrestrial robotics applications.

Whittaker, William↗

JTEC panel report on advanced composites in Japan

The JTEC Panel on Advanced Composites visited Japan and surveyed the status and future directions of Japanese high performance ceramic and carbon fibers and their composites in metal, intermetallic, ceramic and carbon matrices. The panel's interests included not only what composite systems were chosen, but also how these systems were developed. A strong carbon and fiber industry makes Japan the leader in carbon fiber technology. Japan has initiated an oxidation resistant carbon/carbon composite program. The goals for this program are ambitious, and it is just starting, but its progress should be closely monitored in the United States.

Diefendorf, R. J.↗

JTEC Panel report on electronic manufacturing and packaging in Japan

This report summarizes the status of electronic manufacturing and packaging technology in Japan in comparison to that in the United States, and its impact on competition in electronic manufacturing in general. In addition to electronic manufacturing technologies, the report covers technology and manufacturing infrastructure, electronics manufacturing and assembly, quality assurance and reliability in the Japanese electronics industry, and successful product realization strategies. The panel found that Japan leads the United States in almost every electronics packaging technology. Japan clearly has achieved a strategic advantage in electronics production and process technologies. Panel members believe that Japanese competitors could be leading U.S. firms by as much as a decade in some electronics process technologies.

Kelly, Michael J.↗

Microelectronics in Japan

The purpose of this JTEC study is to evaluate Japan's electronic manufacturing and packaging capabilities within the context of global economic competition. To carry out this study, the JTEC panel evaluated the framework of the Japanese consumer electronics industry and various technological and organizational factors that are likely to determine who will win and lose in the marketplace. This study begins with a brief overview of the electronics industry, especially as it operates in Japan today. Succeeding chapters examine the electronics infrastructure in Japan and take an in-depth look at the central issues of product development in order to identify those parameters that will determine future directions for electronic packaging technologies.

Boulton, William R.↗

Research on ignition and flame spread of solid materials in Japan

Fire safety is one of the main concerns for crewed missions such as the space station. Materials used in spacecraft may burn even if metalic. There are severe restrictions on the materials used in spacecraft from the view of fire safety. However, such restrictions or safety standards are usually determined based on experimental results under normal gravity, despite large differences between the phenomena under normal and microgravity. To evaluate the appropriateness of materials for use in space, large amount of microgravity fire-safety combustion data is urgently needed. Solid material combustion under microgravity, such as ignition and flame spread, is a relatively new research field in Japan. As the other reports in this workshop describe, most of microgravity combustion research in Japan is droplet combustion as well as some research on gas phase combustion. Since JAMIC, the Japan Microgravity Center, (which offers 10 seconds microgravity time) opened in 1992, microgravity combustion research is robust, and many drop tests relating to solid combustion (paper combustion, cotton string combustion, metal combustion with Aluminium or Magnesium) have been performed. These tests proved that the 10 seconds of microgravity time at JAMIC is useful for solid combustion research. Some experiments were performed before JAMIC opened. For example, latticed paper was burned under microgravity by using a 50 m drop tower to simulate porous material combustion under microgravity. A 50 m tower provides only 2 seconds microgravity time however, and it was not long enough to investigate the solid combustion phenomena.

Ito, Kenichi↗

Joint US-Japan Observations with the Infrared Space Observatory (ISO): Deep Surveys and Observations of High-Z Objects

Several important milestones were passed during the past year of our ISO observing program: (1) Our first ISO data were successfully obtained. ISOCAM data were taken for our primary deep field target in the 'Lockman Hole'. Thirteen hours of integration (taken over 4 contiguous orbits) were obtained in the LW2 filter of a 3 ft x 3 ft region centered on the position of minimum HI column density in the Lockman Hole. The data were obtained in microscanning mode. This is the deepest integration attempted to date (by almost a factor of 4 in time) with ISOCAM. (2) The deep survey data obtained for the Lockman Hole were received by the Japanese P.I. (Yoshi Taniguchi) in early December, 1996 (following release of the improved pipeline formatted data from Vilspa), and a copy was forwarded to Hawaii shortly thereafter. These data were processed independently by the Japan and Hawaii groups during the latter part of December 1996, and early January, 1997. The Hawaii group made use of the U.S. ISO data center at IPAC/Caltech in Pasadena to carry out their data reduction, while the Japanese group used a copy of the ISOCAM data analysis package made available to them through an agreement with the head of the ISOCAM team, Catherine Cesarsky. (3) Results of our LW2 Deep Survey in the Lockman Hole were first reported at the ISO Workshop "Taking ISO to the Limits: Exploring the Faintest Sources in the Infrared" held at the ISO Science Operations Center in Villafranca, Spain (VILSPA) on 3-4 February, 1997. Yoshi Taniguchi gave an invited presentation summarizing the results of the U.S.-Japan team, and Dave Sanders gave an invited talk summarizing the results of the Workshop at the conclusion of the two day meeting. The text of the talks by Taniguchi and Sanders are included in the printed Workshop Proceedings, and are published in full on the Web. By several independent accounts, the U.S.-Japan Deep Survey results were one of the highlights of the Workshop; these data showed conclusively that the ISOCAM S/N continues to decrease as the square root of time for periods as long as 13 hours.

Sanders, David B.↗

Convective Systems Over the Japan Sea: Cloud-Resolving Model Simulations

Wintertime observations of MCSs (Mesoscale Convective Systems) over the Sea of Japan - 2001 (WMO-01) were collected from January 12 to February 1, 2001. One of the major objectives is to better understand and forecast snow systems and accompanying disturbances and the associated key physical processes involved in the formation and development of these disturbances. Multiple observation platforms (e.g., upper-air soundings, Doppler radar, wind profilers, radiometers, etc.) during WMO-01 provided a first attempt at investigating the detailed characteristics of convective storms and air pattern changes associated with winter storms over the Sea of Japan region. WMO-01 also provided estimates of the apparent heat source (Q1) and apparent moisture sink (Q2). The vertical integrals of Q1 and Q2 are equal to the surface precipitation rates. The horizontal and vertical adjective components of Q1 and Q2 can be used as large-scale forcing for the Cloud Resolving Models (CRMs). The Goddard Cumulus Ensemble (GCE) model is a CRM (typically run with a 1-km grid size). The GCE model has sophisticated microphysics and allows explicit interactions between clouds, radiation, and surface processes. It will be used to understand and quantify precipitation processes associated with wintertime convective systems over the Sea of Japan (using data collected during the WMO-01). This is the first cloud-resolving model used to simulate precipitation processes in this particular region. The GCE model-simulated WMO-01 results will also be compared to other GCE model-simulated weather systems that developed during other field campaigns (i.e., South China Sea, west Pacific warm pool region, eastern Atlantic region and central USA).

Tao, Wei-Kuo↗

L-Band RFI in Japan

In recent years, three instruments have been launched into orbit with the aim of producing global maps of sea surface salinity and soil moisture using the 1400-1427 MHz band: SMOS, Aquarius and SMAP. Although this frequency band is allocated to passive measurements only, RFI (Radio-Frequency Interference) is present in the data of all three missions. On a global scale, the three sensors have observed approximately the same distribution of RFI. Japan is an important exception that has implications for the design of RFI detection algorithms. RFI in Japan is caused by a large number of emitters belonging to the same system (TV receivers) and for this reason some traditional RFI detection strategies detect little to no RFI over Japan. The study of this case has led to an improvement of the approach to detect RFI in Aquarius data.

Aquarius↗

International Symposium on Transport Security of Nuclear and other Radioactive Material; Tokyo, Japan, November 2019

As an outcome of the Fourth Nuclear Security Summit of 2016, held in Washington D.C., the Governments of Australia, Canada, Czech Republic, Finland, France, Hungary, Italy, Japan, Kazakhstan, Morocco, Spain, the Republic of Korea, Thailand, the United Kingdom, and the United States reaffirmed, through INFCIRC/909, their will to further improve the overall security in the transport of nuclear and other radioactive materials. With this goal in mind, each expressed their commitment to further exchange national practices with other countries through the IAEA and the Global Initiative to Combat Nuclear Terrorism (GICNT). They also committed to actively support the IAEA as the central organization for coordinating activities and developing guidance documents and to support the GICNT and the Global Partnership Against the Spread of Weapons and Materials of Mass Destruction in developing and implementing its nuclear transport security activities. Both of these organizations address the commitments regarding nuclear transport security as outcomes of the Nuclear Security Summit 2016. In an effort to continue the momentum from the Nuclear Security Summit, the Government of Japan, in cooperation with the Integrated Support Center for Nuclear Nonproliferation and Nuclear Security of Japan Atomic Energy Agency (ISCN/JAEA), hosted the International Transport Security Symposium in November 2019. With over fifty countries invited to attend, the event exchanged and promoted good practices in several topical area sessions related to the security of nuclear and other radioactive material in transport. Topical sessions included Laws and Regulatory Framework, Physical Protection Systems, Response Actions, and Insider/Information Security. The Symposium built support for transport security and encouraged IAEA Member States to actively work regionally and internationally with the IAEA’s transport security programme through the practical implementation and incorporation of IAEA Nuclear Security Series recommendations and guidance into their national frameworks for transport security. From these sessions, to the host detailed a recommended path forward for future engagements in the security of nuclear and radioactive material in transport. The paper will discuss the Symposium’s outcomes and highlight the forward momentum made by both signatories and non-signatories for the strengthening of all the critical elements of a State’s transport security regime, including physical protection systems, insider threats to the nuclear and radioactive material supply chains, planning and capabilities for law enforcement response to malicious transport security events, and employment of technology to address critical vulnerabilities to the transport of nuclear and other radioactive materials.

Holt, Katherine↗

Total Dust Deposition Flux During Precipitation in Toyama, Japan, in the Spring of 2009: A Sensitivity Analysis with the NASA GEOS-5 Model

We compared the observed total dust deposition fluxes during precipitation (TDP) mainly at Toyama in Japan during the period January - April 2009 with results available from four NASA GEOS-5 global model experiments. The modeled results were obtained from three previous experiments and carried out in one experiment, which were all driven by assimilated meteorology and simulating aerosol distributions for the time period. We focus mainly on the observations of two distinct TDP events, which were reported in Osada et al. (2011), at Toyama, Japan, in February (Event B) and March 2009 (Event C). Although all of our GEOS-5 simulations captured aspects of the observed TDP, we found that our low horizontal spatial resolution control experiment performed generally the worst. The other three experiments were run at a higher spatial resolution, with the first differing only in that respect from the control, the second adding imposed a prescribed corrected precipitation product, and the final experiment adding as well assimilation of aerosol optical depth based on MODIS observations. During Event C, the increased horizontal resolution could increase TDP with precipitation increase. There was no significant improvement, however, due to the imposition of the corrected precipitation product. The simulation that incorporated aerosol data assimilation performed was by far the best for this event, but even so could only reproduce less than half of the observed TDP despite the significantly increased atmospheric dust mass concentrations. All three of the high spatial resolution experiments had higher simulated precipitation at Toyama than was observed and that in the lower resolution control run. During Event B, the aerosol data assimilation run did not perform appreciably better than the other higher resolution simulations, suggesting that upstream conditions (i.e., upstream cloudiness), or vertical or horizontal misplacement of the dust plume did not allow for significant improvement in the simulated aerosol distributions. Furthermore, a detailed comparison of observed hourly precipitation and surface particulate mass concentration data suggests that the observed TDP during Event B was highly dependent on short periods of weak precipitation correlated with elevated dust surface concentrations, important details possibly not captured well in a current global model.

Dust; Wet deposition; Numerical modeling; Japan; P↗

Simulation of compound flooding in Japan using a nationwide model

For this study, a high-resolution, summit-to-sea unstructured-grid model was used to simulate two compound flooding events in different geomorphic settings in Japan: the July 2012 flood in Kumamoto city and July 2018 flood in Okayama City, both caused by a torrential rainfall during seasonal Meiyu front but otherwise exhibiting quite different compound flood characteristics. The model shows good performance in simulating flooding extent; e.g., the Hit Rate for the inundation event in 2018 exceeds 0.9. Sensitivity tests were conducted to determine the roles/significance of levee structures along major rivers in coastal regions. Our results indicate that riverine and oceanic factors as well as levees significantly contribute to the observed flooding extents, and we are able to quantify the contributions from each factor at different locations. The model has been implemented operationally as the first nationwide 3-day compound flooding forecast system for Japan.

54 ENVIRONMENTAL SCIENCES↗

Nonlinear model of infection wavy oscillation of COVID-19 in Japan based on diffusion kinetics

The infectious propagation of SARS-CoV-2 is continuing worldwide, and specifically, Japan is facing severe circumstances. Medical resource maintenance and action limitations remain the central measures. An analysis of long-term follow-up reports in Japan shows that the infection number follows a unique wavy oscillation, increasing and decreasing over time. However, only a few studies explain the infection wavy oscillation. This study introduces a novel nonlinear mathematical model of the new infection wavy oscillation by applying the macromolecule diffusion theory. In this model, the diffusion coefficient that depends on population density gives nonlinearity in infection propagation. As a result, our model accurately simulated infection wavy oscillations, and the infection wavy oscillation frequency and amplitude were closely linked with the recovery rate of infected individuals. In conclusion, our model provides a novel nonlinear contact infection analysis framework.

60 APPLIED LIFE SCIENCES↗

Accuracy of self‐reported weight, height and body mass index among older people in Japan

Aim Weight and height are usually self‐reported in population‐based epidemiological surveys. While the accuracy of self‐reports has been extensively studied in younger populations, less is known in older populations. We investigated the accuracy of self‐reported weight, height and body mass (BMI) in an older cohort in Japan, where overweight/obesity and underweight coexist. Methods We used data from older Japanese adults (≥65 years) participating in the Japan Gerontological Evaluation Study in 2016 to 2017 (7357 men and 9271 women). Self‐report data were linked to objective data obtained from clinical examinations. Results The mean ± standard deviation (SD) age was 74.5 ± 5.8 years, mean ± SD weight, height and BMI were 55.7 ± 10.1 kg, 156.0 ± 8.9 cm and 22.8 ± 3.1, respectively. Results showed high intraclass correlation coefficients for self‐reported and measured values (0.97 for weight; 0.96 for height). While weight/height were overestimated among men (weight by 0.096 kg; height by 0.27 cm) and women (weight by 0.18 kg; height by 0.27 cm), BMI tended to be slightly underestimated (−0.034 kg/m 2 for men; −0.037 kg/m 2 for women). However, the absolute differences between self‐reported and measured values were not negligible; people had a higher risk for both under‐ and overestimation of their BMI category with increasing age. Lower education predicted BMI overestimation, whereas lower income predicted BMI underestimation. Conclusions Overall accuracy of self‐reported body habitus was higher in this cohort of older Japanese compared with previous reports. Nevertheless, misclassification of BMI due to the misreporting of their weight/height was more common among the oldest‐old, as well as those with lower education and income. Geriatr Gerontol Int 2020; 20: 803–810 .

Yazawa, Aki↗

Clusters of COVID ‐19 in long‐term care hospitals and facilities in Japan from 16 January to 9 May 2020

Aim To clarify the association of cluster number and size of coronavirus disease 2019 (COVID‐19) in long‐term care (LTC) hospitals/facilities, general medical/welfare facilities and non‐medical/welfare facilities with morbidity and mortality in 47 prefectures during 16 January to 9 May 2020 in Japan. Methods Information on COVID‐19 clusters ( n ≥2), and morbidity and mortality of COVID‐19 was collected. Results A total of 381 clusters with 3786 infected cases were collected, accounting for 23.9% of 15 852 cumulated cases on 9 May 2020. Although the cluster number (/10 7 subjects) in LTC hospitals/facilities was significantly smaller compared with those in the other two groups, the cluster size in LTC hospitals/facilities was significantly larger than that in non‐medical/welfare facilities. Cluster numbers in general medical/welfare facilities and in non‐medical/welfare facilities were significantly positively correlated with morbidity (/10 5 ), indicating relatively early identification of clusters in these facilities. Unlike in these facilities, cluster size in LTC hospitals/facilities was significantly positively correlated with morbidity, indicating that clusters in LTC hospitals/facilities were finally identified after already having grown to a large size in areas where infection was prevalent. Multivariate logistic regression analysis showed that both cluster number and cluster size only in LTC hospitals/facilities were independently associated with higher mortality (≥median 0.64/10 5 subjects) after adjustment. Conclusions Preventive efforts against COVID‐19 outbreaks even at the early phase of the epidemic are critically important in LTC hospitals/facilities, as both the larger number and size of clusters only in LTC hospitals/facilities were independently linked to higher mortality in prefectures in Japan. Geriatr Gerontol Int 2020; 20: 715–719 .

Iritani, Osamu↗

A review of liquid rocket propulsion programs in Japan

An assessment of Japan's current capabilities in the areas of space and transatmospheric propulsion is presented. The primary focus is upon Japan's programs in liquid rocket propulsion and in space plane and related transatmospheric areas. Brief reference is also made to their solid rocket programs, as well as to their supersonic air breathing propulsion efforts that are just getting underway.

Merkle, Charles L.↗

ETS-5, ETS-6, and COMETS projects in Japan

Three satellite communication projects now in progress in Japan are described. The first is a project to establish a telecommunication network for tele-education, TV conference, and tele-medicine in the Asia-Pacific region by using the Japan's Engineering Test Satellite-5 (ETS-5). The second is a project of the ETS-6 satellite, to be launched in 1993, for inter-satellite communication, mobile and fixed communication, and millimeter wave personal communication experiments. The third is a project of the Communications and Broadcasting Engineering Test Satellite (COMETS), to be launched in 1997, for advanced mobile satellite communication, inter-satellite link, and advanced broadcasting experiments at higher frequencies.

Iida, Takashi↗