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141.
Tatsuo Akashi 《土木工程与建筑:英文版》2014,(9):1157-1167
The purpose of this paper is to clarify the mechanism of planning failure on land use control in case of sprawl developments of large scale commercial facilities, which is often seen in many countries. The author demonstrates actual three cases in Japan: a huge commercial development established in the middle of rice field between the two local cities, two huge commercial accumulations established at the opposite fringes of urban area, and many large commercial developments established one by one within the small municipalities surrounding a central city. And by examining the statistical sales amount, the author describes that these huge suburban commercial developments apparently deprived the sales of the downtown. Through analyzing these cases, the author empirically stated that for the motorized local cites, the optimum location of commercial accumulation is no longer the central area of the city but about 15 min away from the center with the smooth accessible arterial road. At last, the author mentions that the "planning failure" could be occurred if the territory of planning authority and the scale of the development are inconsistent, such as the authority of small municipal government and the large scale commercial facility which impacts beyond the municipal boundary. 相似文献
142.
Fusaomi Nagata Takanori Mizobuchi Keigo Watanabe 《The International Journal of Advanced Manufacturing Technology》2011,57(9-12):1029-1041
In this paper, a desktop-size NC machine tool is first presented to have multi-application function, such as 3D-machining modes with and without handling a machining force, and profiling-control modes with and without using stick-slip motion. The NC machine tool consists of three single-axis devices with a high resolution of 1???m in position. A ball end mill called router bit or a thin wood-stick tool can be attached to the tip of the z-axis. The proposed machine tool realizes compliant motion required for the profiling control along a desired trajectory. The profiling-control mode can be applied to the lapping process of a metallic LED lens cavity. Next, a control strategy with fine stick-slip motion is further added to the profiling-control system to improve the lapping performance. The fine stick-slip motion is generated orthogonally to the direction of the tool movement. Generally, the stick-slip motion is an undesirable phenomenon to be eliminated in precision machineries. However, the proposed machine tool employs the fine stick-slip motion to partly regulate slight finishing energy. The effectiveness of the machine tool is demonstrated through an actual machining test of a wood material and a lapping test of a metallic LED lens cavity. 相似文献
143.
Solar thermal applications require some means of thermal energy storage. Amongst several storage concepts, latent heat storage is quite suitable because of its high storage density and almost constant temperature during charging and discharging. The temperature range between 200 and 300°C is considered to be important for solar total energy systems. In this temperature range, sodium nitrate and its mixed salts with other nitrates including eutectic and off-eutectic salts are candidates.
The present paper deals with heat transfer in a latent heat storage unit utilizing these salts. A method of rough estimation of the thermal conductivity of the storage materials is described, and the temperature history of the storage material experimentally obtained is compared with numerical solutions and found to be in reasonably good agreement.
It is seen that the temperature of the heat transfer surface quickly drops soon after the appearance of a solid phase due to low thermal conductivity of these salts. Ways to avoid this temperature drop are discussed. 相似文献
144.
Masataka Maita Tatsuo Yamanaka Yoshiaki Ohkami Shigeo Kobayashi 《International Journal of Hydrogen Energy》1990,15(12):871-877
For the promotion of extended and diversified space activities in Japan, it is required to build immediately the technology bases capable of supporting such space activities and thereby to expand positively international cooperation as one of Japan's roles towards the world's prosperity of the 21st century. Especially, development of the manned space transportation system to and from lower earth orbit is the key issue, requiring an unprecedented approach. The Single Stage to Orbit(SSTO) Aerospace Plane is the unique answer to this issue. This paper will discuss the perspective on the research and development of the Space Plane in Japan. The topics will cover a long range R&D scenario and current activities of the related organizations in Japan. 相似文献
145.
Y Kaneko H Okabe N Nagata J Kobayashi S Kanemoto 《Canadian Metallurgical Quarterly》1998,65(6):1783-1784
A 9-month-old boy with left juxtaposition of the atrial appendages, tricuspid atresia, pulmonary atresia, and ventriculoarterial discordance underwent anastomosis between the atrial appendages after failure of balloon/blade atrial septostomy because of restrictive atrial septal defect. For surgical creation of atrial communication in patients with juxtaposed atrial appendages, anastomosis between the atrial appendages seemed to be safer, more effective, and less invasive than septectomy by Blalock-Hanlon technique or inflow occlusion technique. 相似文献
146.
By placing a galvanic-type steam sensor on the fuel electrode of a solid oxide fuel cell, water vapour pressure in the anode during discharge was successfully measured. The change in steam concentration in the anode, which was calculated from the e.m.f. of the sensor, was compared with the variation of anodic overvoltage measured by the usual d.c. interruption method. As a result, the water vapour pressure was confirmed to increase as the discharge current increased, and most of the anodic overvoltage could be ascribed to the hydrogen concentration overvoltage. 相似文献
147.
H Nakata Y Kikuchi T Tode J Hirata T Kita K Ishii K Kudoh I Nagata N Shinomiya 《Canadian Metallurgical Quarterly》1998,89(7):733-740
Ginsenoside Rh2 (Rh2), isolated from an ethanol extract of the processed root of Panax ginseng CA Meyer, inhibits the growth of B16 melanoma cells. This study was designed to evaluate the ability of Rh2 to inhibit growth of human ovarian cancer cells (HRA) in vitro and in nude mouse. Rh2 inhibited proliferations of various established human ovarian cancer cell lines in a dose-dependent manner between 10 and 60 microM in vitro and induced apoptosis at around the IC50 dose. When HRA cells were inoculated s.c. into the right flank of nude mice, all mice formed a palpable tumor within 14 days. Although i.p. administration of Rh2 alone hardly inhibited the tumor growth, when Rh2 was combined with cis-diamminedichloroplatinum(II) (CDDP) the tumor growth was significantly inhibited, compared to treatment with CDDP alone. When mice were treated p.o. with Rh2 daily (but not weekly), the tumor growth was significantly (P<0.01) inhibited, compared to CDDP treatment alone. When Rh2 was combined with CDDP, the degree of tumor growth retardation was not potentiated. The survival time was significantly (P<0.05) longer than that of medium alone-treated controls or the group treated with CDDP alone. Then, we examined whether p.o. administration of Rh2 has a dose-dependent inhibitory effect on the tumor growth. I.p. and weekly administration of CDDP had more potent antitumor activity in the order of 1 mg/kg, 2 mg/kg and 4 mg/kg, whereas p.o. and daily administration of Rh, (0.4 to 1.6 mg/kg) not only had antitumor activity comparable to that of 4 mg/kg CDDP, but also resulted in a significant increase of the survival. Doses of Rh2 used in this study did not result in any adverse side-effects as confirmed by monitoring hematocrit values and body weight, unlike 4 mg/kg CDDP, which had severe side-effects. It is noteworthy that p.o. but not i.p. treatment with Rh2 resulted in induction of apoptotic cells in the tumor in addition to augmentation of the natural killer activity in spleen cells from tumor-hearing nude mice. Thus, particularly in view of the toxicity of CDDP, Rh2 alone would seem to warrant further evaluation for treatment of recurrent or refractory ovarian tumor. 相似文献
148.
Tsutomu Nagata Yoichi Nagata Hirokazu Koshimitsu 《Computers & Industrial Engineering》1993,24(4):561-569
The position of a production management system in a computer-integrated manufacturing (CIM) system is to serve as the nucleus of the plant CIM system that connects the plant production to other departments such as marketing, research and development, and distribution departments. A production management system that integrates the flow of goods with information in a plant, and thus manages production in it, was developed as the first step toward application of CIM to a powder plant. The method of building a distributed system is one way to build a CIM system. This method creates a system in the required function units, which are connected by a network to expand the system function. It offers advantages in extensibility, flexibility, and rapid implementation. 相似文献
149.
Photodegradation of incombustible polymer materials [high-density (HD) and low-density (LD) polyethylene (PE) containing 0.5 to 2.0 phr of decabromodiphenyl ether (DBDE) or tetrabromobisphenol A (TBA) as a flame retardant] were studied using an Okazaki Large Spectrograph (OLS). Samples were irradiated in air at 23°C with monochromatic light of wavelengths at 260, 280, 300, 320, 340, and 360 nm. Ultraviolet and Fourier transform infrared (FTIR) spectra were taken to estimate the chemical changes caused by photoirradiation. Molecular weight change was followed by gel permeation chromatography (GPC) measurements. It was found that the photostability of PE samples was reduced by the addition of flame retardants. The threshold wavelengths of photodegradation are 320 nm and 360 nm for PE–TBA samples and PE–DBDE samples, respectively. Main-chain scission is favored when the irradiation was carried out with the light of wavelength 300 nm for HDPE–DBDE and HDPE–TBA samples. The most effective irradiation wavelengths for crosslinking are found to be 300 nm and 280 nm for LDPE–DBDE and LDPE–TBA samples, respectively. 1995 John Wiley & Sons, Inc. 相似文献
150.
H Aida K Takakuwa H Nagata I Tsuneki M Takano S Tsuji T Takahashi T Sonoda M Hatae K Takahashi K Hasegawa H Mizunuma N Toyoda H Kamata Y Torii N Saito K Tanaka M Yakushiji T Araki K Tanaka 《Canadian Metallurgical Quarterly》1998,4(1):235-240
BACKGROUND: Stentless aortic xenografts are an important addition to the range of prosthetic valves. So far their use has been restricted to a limited number of study centers. This report summarizes the principal findings from the Second International Symposium on Stentless Bioprostheses. Attention is focused on the Toronto SPV and Freestyle valves recently approved by the United States Food and Drug Administration. METHODS: Stentless xenografts are used predominantly in elderly patients with aortic stenosis. Implant techniques are more complex than for stented valves, as reflected by longer ischemic and cardiopulmonary bypass times. The valves have been subjected to detailed serial echocardiographic assessment and clinical follow-up. RESULTS: The hemodynamic characteristics resemble those of the aortic homograft. There is a progressive increase in effective orifice area and decrease in transvalvular pressure gradients with time. Left ventricular mass index and wall thickness normalize between 6 and 12 months postoperatively. Left ventricular remodeling is accompanied by improved symptomatic status and a low incidence of valve-related complications. Limited comparative studies suggest important benefits over stented xenografts. Improved hemodynamics may translate into better bioprosthetic durability. CONCLUSIONS: Reproducible and reliable implant methods should be taught carefully, but the hemodynamic advantages are substantial. Stentless xenografts are ideal for the elderly patient with aortic stenosis. 相似文献