SEARCH · Engineering Papers
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.
The space programs of the Soviet Union, Japan, and China are discussed. The types of launch vehicles they used and the classes of spacecraft they launched are examined. The political motivations of these nations are analyzed.
The results are presented for the systematic measurement of cosmic ray showers in the first carbon chamber of Japan-USSR joint experiment at Pamir Plateau. The intensity and the energy distribution of electromagnetic particles, of hadrons and of families are in good agreement with the results of other mountain experiment if the relative error in energy estimation is taken into consideration.
A detailed description of the event detected in the second chamber of Japan-URSS Collaboration is presented. A preliminary description was already published and from that time a careful microscopic scanning was carried out.
A search for mini-clusters, very collimated shower clusters of hadrons and electromagnetic particles, is made for the hadron and gamma families observed by Japan-USSR joint carbon chamber at Pamir. The existence of anomalous correlation between hadrons and electromagnetic particles is found. The decascading method is applied to the families and it is found that 11 clusters which include hadrons as members have smaller spread, Er 3.5 GeV.m and larger lateral spread, E'R' 100 GeV.m, from the family center. In the simulated events, such clusters were found to be very rare.
The current status of communications satellite development in Japan is presented. It is shown that beginning with research on satellite communucations in the late 1950's, progress was made in the areas of communications, remote sensing, and technology experimentation. The current status of communication satellites is presented, stressing development in the areas of CFRP construction elements, the use of LSI and MIC circuits, advanced multibeam antenna systems, Ku and Ka band transmission systems, and the shift to small-scale earth stations. Methods for reducing costs and increasing transmission efficiency are shown. The technical specifications of all satellite projects currently under development are given. Users of Japanese communications satellite are presented.
The progress of cryocoolers and related devices in Japan is reviewed. The Japanese National Railways has developed the light weight 4 K on-board refrigerators since 1977 as part of the MAGLEV train program. Superconducting and cryogenic fundamental technology was examined which included high performance cryocooler, magnetic refrigerator and superfluid refrigeration. Space cryogenics such as the cooling systems of IR-detectors was studied. Cryocooler for special applications such as cryopump, NMR-CT and JJ devices was investigated. Compact heat exchangers, high performance regenerators and reliable compressors are investigated as a critical component technology.
The stratospheric aerosol state in 1982 and 1983 was in a violet excitation due to the eruption of Mt. El Chichon. A number of direct and indirect soundings of the stratosphere confirmed that the aftereffect of it covered almost the entire Northern Hemisphere by the end of 1982 (e.g., POLLACK et al., 1983). The lidar system constructed at Toyokawa (34.8 deg N, 137.4 deg E) have entered routine base observations since December 1982 (IWATA et al., 1983). The state of observations was 8 months after the eruption, and researchers missed monitoring the drastic variations in the stratosphere just following the event. However, the El Chichon cloud over Japan was reported to have reached the second maximum concentration in November or December 1982 according to the lidar observations at Tsukuba, Nagoya and Fukuoka, so the researchers' observations corresponded to the decaying phase of it. Presented are some characteristics of the aerosol profile over Toyokawa during a period of 20 months from December 1982 to July 1984.
The stratospheric-tropospheric exchanges play an important role in determining the distribution and residence time of ozone, aerosol and other substances in the stratosphere and troposphere. The ozone transport is estimated from the stratosphere into the troposphere by so-called tropopause folding event associated with the polar front jet stream. It is shown that in winter ozone transport occurs mainly in the region to the north of Japan in Asia. The ozone transport rate is estimated. Vertical velocity was estimated by marking the air parcel of an observation aircraft and tracking is on the isentropic surface.
A 2.3 GHz traveling-wave maser/closed-cycle refrigerator (TWM/CCR) that is used in the DSN was installed and successfully operated on the 64 m antenna at Usuda, Japan. The TWM/CCR supported the first very long baseline interferometry (VLBI) experiment to use an orbiting spacecraft as one of the receiving antennas. The experiment required a 15 K receiving system over a 2271 to 2285 MHz bandwidth. The maser installation was made during June 1986, and successful VLBI measurements were made during July and August 1986 and again in January 1987.
About 400 CZCS (coastal zone color scanner) scenes covering the Japan area in November 1978-May 1982 were processed to study the applicability of the Gordon-Clark atmospheric correction scheme which produces water-leaving radiances Lw at 443 nm, 520 nm, and 550 nm as well as phytoplankton pigment maps. Typical spring-fall aerosol radiance in the images was found to be 0.8-1.5 micro-W/sq cm-nm-sr, which is about 50 percent more than reported for the US eastern coastal images. The correction for about half the data resulted in negative Lw (443) values, implying overestimation of the aerosol effect for this channel. Several possible reasons for this are considered, including deviation of the aerosol optical thickness tau(a) at 443 nm from that estimated by Angstrom's exponential law, which the algorithm assumes. The analysis shows that, assuming the use of the Gordon-Clark algorithm, and for a pigment concentration of about 1 microgram/l, -40 percent to +100 percent error in satellite estimates is common. Although this does not fully explain the negative Lw (443) in the satellite data, it seems to contribute to the problem significantly, together with other error sources, including one in the sensor calibration.
An overview of aerodynamic aircraft design methods and their recent applications in Japan is presented. A design code which was developed at the National Aerospace Laboratory (NAL) and is in use now is discussed, hence, most of the examples are the result of the collaborative work between heavy industry and the National Aerospace Laboratory. A wide variety of applications in transonic to supersonic flow regimes are presented. Although design of aircraft elements for external flows are the main focus, some of the internal flow applications are also presented. Recent applications of the design code, using the Navier Stokes and Euler equations in the analysis mode, include the design of HOPE (a space vehicle) and Upper Surface Blowing (USB) aircraft configurations.
The National Space Development Agency of Japan (NASDA) began developing Nickel-Cadmium (Ni-Cd) cells for space use in 1985. Sanyo Electric was responsible for the cell design, manufacturing, and initial testing. The cell life was evaluated by NASDA in the Tsukuba Space Center (TKSC). The development is presently in the qualification Test (QT) phase. Recent life-cycle data for 35 Ah Ni-Cd cells are presented.
The basaltic sills from ocean drilling program sites 794 and 797 in the Yamato Basin of the Japan Sea are characterized petrographically on the basis of a detailed study of the composition of relict phenocryst and groundmass phases. The systematic variation in the rock compositions is discussed. Results of 1-atm melting experiments on a relatively primitive basalt from site 797 are reported. The sills are found to constitute two distinct groups of suites: primitive, olivine-bearing suites with low potassium and primitive olivine-bearing to evolved, olivine-free suites with relatively high potassium. A pseudoinvariant reaction relationship between olivine and augite and magnetite is inferred. Complex magmatic and tectonic evolutions in the region, perhaps reflecting a transitional stage between subduction zone activity and back arc spreading, are suggested.
Results are presented from temporally dense measurements of crustal deformation associated with the convergence of the Eurasian (EUR), Pacific, North American, and Philippine Sea (PHS) plates, carried out in April 1988 by a 10-station GPS fixed-point network established in central Japan. Using regional orbit relaxation methods, the analysis of the first 17-month data revealed significant horizontal deformation across the Suruga trough. Namely, it was found that a site in the northern tip of PHS plate moved nearly westward with a velocity of 28 +/-5 mm per year, and a site at the southeastern tip of EUR plate moved south-southwestward with a velocity of 18 +/-5 mm per year. A significant vertical uplift with a velocity of 20 mm/yr was detected at a site inland of the Tokai district located in the Akaishi uplift zone and at a site on the Hatsushima Island in Sagami Bay.
One of the most significant developments in the field of technical communication during the 1980's and 1990's has been a growing interest in international technical communication, including technical communication in Japan. This article provides insights into aspects of the Japanese language and culture that affect Japanese technical communication practices. These insights are then used to interpret and report the results of a survey of Japanese aerospace engineers and scientists concerning the kinds of communication products they produce, the kinds they use, and the specific recommendation they would offer to designers of academic programs in technical communication.
The hypothesis that present-day deformation within the southern Kuril forearc is driven by oblique subduction of the Pacific plate is tested using 397 horizontal slip directions derived from shallow-thrust earthquakes from the Kuril and Japan trenches for the period 1963-1991. A simple two-plate model fits the 397 slip vectors significantly worse than a model that permits strike-slip motion of the southern Kuril forearc relative to the overlying plate. Weighted, mean slip directions along the southern Kuril trench are systematically rotated toward the direction orthogonal to the trench, which implies that the net convergence is partitioned into less oblique subduction and trench-parallel displacement of the southern Kuril forearc. The angular discrepancy between the observed slip direction and the direction predicted by the NUVEL-1 Pacific-North America Euler vector implies that the southern Kuril forearc translates 6-11 mm/yr to the southwest relative to the overlying North American plate. These results are consistent with geologically, geodetically, and seismologically observed convergence at the leading edge of the forearc sliver in southern Kokkaido and with previously inferred extension at the trailing edge of the sliver, which is located at the Bussol Strait at 46 deg N.
One of the most significant developments in the field of technical communication during the 1980s and 1990s has been a growing interest in international technical communication, including technical communication in Japan. This article provides insights into aspects of the Japanese language and culture that affect Japanese technical communication practices. The authors then use these insights to interpret and report the results of a survey of Japanese aerospace engineers and scientists concerning the kinds of communication products they produce, the kinds they use, and the specific recommendations they would offer to designers of academic programs in technical communication.
Three satellite infrared techniques of increasing complexity for the estimation of rainfall are compared: (1) the GOES precipitation index (Arkin, 1979, 1983), (2) the Negri-Adler-Wetzel (Negri et al., 1984) technique, and (3) the convective-stratiform technique (CST), described by Adler and Negri (1988). It is shown that all three techniques performed poorly in estimating the rain maxima over southeastern Japan associated with shallow orographic warm rain systems. However, when the data set was limited to the ocean-only points, the CST method performed best, with the lowest bias, the lowest rms, and the highest correlation. Daily rainfall estimates had rms errors of almost 200 percent of the mean, and negative biases of about 50 percent of the mean.