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11.
Macroscopic analysis of design processes based on a scheme for coding designers' cognitive actions 总被引:1,自引:0,他引:1
We have devised a new scheme for coding designers' cognitive actions from video/audio design protocols. Designers' actions are coded into four cognitive levels; physical, perceptual, functional and conceptual. Relations between actions belonging to different levels, such as dependencies and triggering relations, are also coded. The present scheme has two benefits. First, we found that design actions are definable in a systematic way using the vocabulary of the scheme, and thus a designer's cognitive behaviours in each of local design stages is represented as a structure composed of defined primitive actions. This is expected to lay the foundation for microscopic analyses of how particular types of actions contribute to the formation of key design ideas. Second, this scheme is suitable for macroscopic analyses of how designers cognitively interact with their own sketches. We examined, for a practising architect, the ways in which drawing, inspection of drawings, perception, and functional thoughts correlated with one another in his design process. The findings suggest that design sketches serve not only as external memory or as a provider of visual cues for association of non-visual information, but also as a physical setting in which design thoughts are constructed on the fly. 相似文献
12.
The causes of lightning outage are subdivided into direct lightning strokes and induced lightning strokes, which are identified by the characteristics of the lightning overvoltage. In the past, lightning protection devices were directed mainly toward the latter, and attention has been focused on the installation of lightning protection devices, ground wires, and reinforcement of insulators. However, lightning outages continue to occur. Thus it is extremely important to clarify the fault characteristics of lightning surges and to study the effectiveness of various lightning protection devices by considering both direct lightning stroke and induced lightning stroke in order to prevent lightning outage in the future. In this research, the electromagnetic transients program (EMTP) has been applied to the direct lightning stroke, and the induced lightning outage analysis program for multiple conductor systems has been applied to the induced lightning stroke to study the effectiveness of lightning protection devices provided by combination of various lightning protection devices. The most effective lightning protection schemes are analyzed and evaluated based on verification tests on the full scale models as well as economic considerations. 相似文献
13.
GB virus C (GBV-C) RNA was detected in five of 18 patients with aplastic anaemia who had received blood transfusions, whereas it was not detected in eight patients who had not received any transfusions. Antibody against hepatitis C virus (anti-HCV) was detected in nine patients in the transfusion group, compared with one of eight who had not received any transfusions. Therefore, the route of transmission of both GBV-C and HCV in these patients appeared to have been multiple blood transfusion. Since all of the GBV-C RNA-positive patients harboured anti-HCV, GBV-C seems to frequently superinfect with HCV. Neither GBV-C nor HCV is likely to have been a causative agent of the anaemia in the cases examined. 相似文献
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Keishi Sakamoto Atsushi Kasugai Masaki Tsuneoka Koji Takahashi Yukiharu Ikeda Tsuyoshi Imai Takashi Nagashima Mitsuru Ohta Tsuyoshi Kariya Kenichi Hayashi Yoshika Mitsunaka Yosuke Hirata Yasuyuki Itoh Yukio Okazaki 《Journal of Infrared, Millimeter and Terahertz Waves》1997,18(9):1637-1654
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window. 相似文献
16.
Y Nakajima O Mikami M Yoshioka Y Motoi T Ito Y Ishikawa M Fuse K Nakano K Yasukawa 《Canadian Metallurgical Quarterly》1997,62(3):297-298
The presence of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) activities was determined in milk and serum of cows with naturally occurring coliform mastitis (CFM). TNF-alpha was detected in the sera from 26 of 32 cows with CFM. TNF-alpha levels were higher in the sera than in the milk. IL-6 was high in the sera of surviving CFM animals, but was low in animals that died and in healthy controls. Furthermore, the mean level of IL-6 was 20-fold higher in the milk than in the sera of mastitic cows. The level of IL-6 in the serum was correlated to that in the milk in individual animals. The presence of IL-6 and TNF-alpha in the sera appears to relate to severe clinical condition of CFM, in the milk whereas they may play a role in generating inflammation of the mammary gland. 相似文献
17.
K Nakano S Ohta K Nishimaki T Miki S Matuda 《Canadian Metallurgical Quarterly》1997,350(9088):1367-1368
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Y Ota Y Nakano H Yamaguchi K Yoshida T Shirafuji A Adachi 《Canadian Metallurgical Quarterly》1993,20(8):1055-1057
In a 63-year-old male patient with gastric cancer having multiple liver metastases, the metastatic lesions responded well to postoperative staggered intraarterial infusion therapy with MTX and 5-FU. The intraarterial infusion therapy was administered once a week. A total of 5 courses of this therapy produced marked regression of liver metastases and remarkable necrosis. The effect was thus rated as PR. The patient is healthy and has been successfully rehabilitated. His dose is oral 5-FU (200 mg x 2). 相似文献
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