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排序方式: 共有735条查询结果,搜索用时 15 毫秒
51.
Satoshi Miyaguchi Shinichi Ishizuka Takeo Wakimoto Jun Funaki Yoshinori Fukuda Hirofumi Kubota Kenji Yoshida Teruichi Watanabe Hideo Ochi Tsuyoshi Sakamoto Masami Tsuchida Isamu Ohshita Teruo Tohma 《Journal of the Society for Information Display》1999,7(3):221-226
Abstract— A full-color 5.2-inch 1/4-VGA passive-matrix organic LED display has been developed, adopting selective deposition for the different emitting materials. The display features 320 (×3) × 240 pixels with an equivalent pixel size of 0.33 × 0.33 mm, white peak luminance of over 150 cd/m2, and power consumption of 6 W. 相似文献
52.
Summary As part of current R&;D work focused on developing the intelligence of arc welding robots, this paper deals with the problem of weldpool sensing and control. To obtain high‐quality welding, it is important to control the weldpool depth in robot welding regardless of any external disturbance, such as irregular groove gap. The method of controlling the weldpool depth without a mathematical model is discussed. Since it is difficult to measure the weldpool depth directly, it is estimated from the weldpool surface shape, groove gap, and welding current. A neural network is used to estimate the weldpool depth without a mathematical model. The weldpool depth is controlled from the output of the neural network using the fuzzy controller. Neural network and fuzzy controller application is validated in welding experiments. 相似文献
53.
Kazuhiro Ohyama Teruo Hamaoka Greg Asher Mark Sumner 《Electrical Engineering in Japan》2009,166(1):67-81
This paper proposes a method for the design of the adaptive rotor flux observer gain to improve stability at low speed and in regenerating mode. The method is based on stability analysis, which utilizes a linearized model considering all systems, including each control loop. Therefore, the proposed method considers the effects of motor constants and control circuit constants. The stability analysis using the transfer function for the rotor speed considers the arrangement of poles and zeros and the steady‐state error. The rotor flux observer gain which improves the stability for each operating condition is ascertained. This paper also proposes a real‐time tuning method for the observer gain. The validity of the proposed method was confirmed by simulation using Matlab Simulink and by experiment. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 67–81, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20715 相似文献
54.
55.
The purpose is to realize miniaturized and broadband function blocks with very simple configurations for multifunction monolithic microwave circuits. FET-sized combiners and dividers, in phase and out of phase, based on a novel line-unified-FET (LUFET) concept are described and demonstrated. Some effective extensions such as extended combiner LUFETs, magic T LUFETs, and phase inverter LUFETs are also described. The extension of the basic combiner and divider LUFETs allows the realization of various circuit functions in a very small area. The area of fabricated LUFETs is between 0.1 and 0.3 mm2, and the operating frequency bandwidth approaches 20 GHz. The LUFET mitigates the size and complexity problems considerably and expands the application of combiners and dividers to various multifunction microwave monolithic integrated circuits (MMICs) 相似文献
56.
Manufacturing exists to create value. However, historically, discussion of economic issues in manufacturing primarily emphasizes cost. It is becoming more difficult to understand and control values of products and services in response to rapid globalization and networking. This paper presents a discussion of the nature of value considering a history of axiology, design problems of artifacts, social dilemmas, network externalities, and sustainability. Promising academic methodologies are presented herein with emphasis on transdisciplinary and synthetic approaches. Value creation models based on Emergent Synthesis and co-creative decision-making are presented. This paper involves some important study examples of service and production toward sustainable value creation in society. 相似文献
57.
Ray Nakashima Shuanghui Hao Hideki Honda Ryuichi Oguro Hidekazu Miyakawa Teruo Tsuji 《Electrical Engineering in Japan》2004,147(4):68-76
In this paper, position control of a linear slider with twin linear drives is considered. Recently, for high‐speed response, several linear motors have been used for linear slider systems. In such a linear slider, if the linear drives are controlled individually, their position responses may undergo vibrational disturbance by interaction with the output of the motors. To control this vibration, this paper presents a dynamic model of a linear slider system which consists of two motion systems decoupled by coordinate transformation, and proposes a feedback controller which is designed for these two decoupled systems. The effectiveness of the proposed method is confirmed by experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 68–76, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10291 相似文献
58.
Hien TT Nam PP Yasuhiro S Takayuki K Norimichi T Hiroshi B 《The Science of the total environment》2007,382(1):70-81
A comparative study of polycyclic aromatic hydrocarbons (PAHs) associated with particulate matter (TSP) in the ambient air in an urban area in Ho Chi Minh City, Vietnam and in Osaka, Japan was carried out from 2005 to 2006. The objective of this study was to investigate the environmental levels, emission sources, seasonal variations and health risk of eleven PAHs in the two cities, especially Ho Chi Minh City where air pollution is becoming a serious concern. The results showed that the concentrations of TSP and total PAHs were significantly higher in Ho Chi Minh City than levels in Osaka. The concentrations of 5- and 6-ring PAHs (BeP, BbF, BkF, BaP, BghiP and InP) were much higher in TSP samples in Ho Chi Minh City than in Osaka, accounting for 82% and 51% of total PAHs, respectively. These PAHs are known to be highly carcinogenic and mutagenic in humans. Vehicular emission is suggested as one of the main pollution sources of PAHs in both cities. Motorcycles and gasoline automobiles are suggested as the main emission sources of PAHs in Ho Chi Minh City, whereas diesel automobiles are the primary source in Osaka. Seasonal variations of PAHs were observed in this study; higher concentrations of PAHs were found in the rainy season (May-December) and lower concentrations corresponded to the dry season (February-April) in Ho Chi Minh City, while higher concentrations of PAHs were observed in the winter (November-January) in Osaka. The number of sunshine hours was an important meteorological factor affecting seasonal variations of PAHs in Ho Chi Minh City, while the temperature was a main factor causing the variations of PAHs in Osaka. The high BaP equivalent concentration of 5- and 6-ring PAHs even in the ambient air is an alarming signal for harmfulness to human health and environmental quality in Ho Chi Minh City. 相似文献
59.
对影响超临界CO2流体处理苎麻纤维的因素,如温度、压力、时间以及助溶剂进行正交试验,对处理后的苎麻纤维的含杂情况、微结构、机械物理性能和热稳定性等性质作了测试分析。结果表明,超临界CO2流体处理苎麻织物的最佳工艺条件为:工作温度120℃、压力25MPa、时间40min、助溶剂0.1%。该处理可改善苎麻纤维的性能,提高其膨胀性,有利于后续加工,并为其进一步改性打下基础。 相似文献
60.
Minamida K Sujaya IN Tamura A Shigematsu N Sone T Yokota A Asano K Benno Y Tomita F 《Journal of Bioscience and Bioengineering》2004,98(4):244-250
Di-D-fructofuranose-1,2':2,3'-dianhydride (DFA III) was shown to enhance Ca absorption in rat and human intestine. The effects of DFA III administration (9 g per day for 4 weeks that corresponded to 3-fold the optimal dosage of DFA III) on human intestinal microbiota were studied using denaturing gradient gel electrophoresis (DGGE). The major groups of human intestinal microbiota reported previously: the Bacteroides, the Clostridium coccoides group (Clostridium cluster XIVa), the Clostridium leptum group (Clostridium cluster IV), and the Bifidobacterium group were detected. The similarity of 30 DGGE profiles based on the V3 region (before and after administration to the 15 subjects) of the 16S rDNA were calculated using Pearson's correlation based on numbers, positions and intensity of bands, and then a dendrogram of DGGE profiles was constructed by the unweighted pair group method using arithmetic average (UPGMA) clustering method. By these analyses, no difference in DGGE profiles after DFA III administration was observed in healthy subjects, while two subjects with chronic constipation showed different profiles, namely on numbers, positions and the intensity of some bands. Their stools were softer and stool frequencies increased and they obtained relief from constipation. 相似文献