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131.
In this study, we introduce a comprehensive design methodology of hybrid fuzzy controllers (HFCs). The hybrid facet of the proposed architecture of the controller manifests in the form of a convex combination of a standard proportional integral derivative (PID) controller and a fuzzy controller. The design procedure dwells on the use of evolutionary computing (genetic algorithms) and an autotuning algorithm based on estimation modes. The tuning of the scaling factors of the HFC is an essential component of the entire optimization process. Numerical studies are presented and a detailed comparative analysis is included as well. 相似文献
132.
KH Guppy TC Origitano OH Reichman S Segal 《Canadian Metallurgical Quarterly》1997,41(3):615-9; discussion 619-20
OBJECTIVE: Intimate to the application of lateral transtemporal approaches to the cranial base are the identification, manipulation, and/or the sacrifice of the venous anatomy of the inferolateral temporal lobe and the superior petrosal sinus and the transection of the tentorium. This study demonstrates the relationship and variability of the venous drainage of the lateral and inferior surfaces of the temporal lobe. METHODS: Twenty-one specially prepared, injected cadaver specimens yielded 40 temporal lobes for examination. The venous systems in these specimens were traced from their origins on the temporal lobe (venous drainage complexes) to the transverse/petrosal sinuses, and the geometry of these venous complexes (venous configuration) was noted. The measurements of each complex's entry to the sinuses were noted. RESULTS: Four distinct venous drainage complexes were identified: 1) the lateral complex, 2) the anteroinferior complex, 3) the medial-inferior complex, and 4) the posteroinferior complex. Three basic venous configurations were found: 1) the candelabra of veins uniting to form one large draining vein, 2) multiple independent draining veins, and 3) venous lakes running in the tentorium before entering the sinuses. The lateral complex, incorporating the classic "vein of Labbé," was present in 100% of the specimens. However, in the majority of cases, it did not represent the dominant venous drainage of the lateral and inferior surfaces of the temporal lobe. CONCLUSION: An understanding of the complexity and diversity of the venous drainage complexes and their configurations is necessary to avoid venous complications during lateral cranial base surgery. 相似文献
133.
OH F?rde 《Canadian Metallurgical Quarterly》1998,47(9):1155-1159
Epidemiology is the main supplier of "bases of action" for preventive medicine and health promotion. Epidemiology and epidemiologists therefore have a responsibility not only for the quality and soundness of the risk estimates they deliver and for the way they are interpreted and used, but also for their consequences. In the industrialised world, the value of, and fascination with health is greater than ever, and the revelation from epidemiological research of new hazards and risks, conveyed to the public by the media, has become almost an every-day phenomenon. This "risk epidemic" in the modern media is paralleled in professional medical journals. It is in general endorsed by health promoters as a necessary foundation for increased health awareness and a desirable impetus for people to take responsibility for their own health through behavioural changes. Epidemiologists and health promoters, however, have in general not taken the possible side effects of increased risk awareness seriously enough. By increasing anxiety regarding disease, accidents and other adverse events, the risk epidemic enhances both health care dependence and health care consumption. More profoundly, and perhaps even more seriously, it changes the way people think about health, disease and death--and ultimately and at least potentially, their perspective on life more generally. The message from the odds ratios from epidemiological research advocates a rationalistic, individualistic, prospective life perspective where maximising control and minimising uncertainty is seen as a superior goal. The inconsistency between applying an expanded health concept, comprising elements of coping, self-realisation and psycho-physical functioning, and imposing intolerance to risk and uncertainty, is regularly overlooked. Acceptance and tolerance of risk and uncertainty, which are inherent elements of human life, is a prerequisite for coping and self-realisation. A further shift away from traditional working-class values like sociability, sharing, conviviality and tolerance can not be imposed without unwanted side effects on culture and human interaction. The moral and coercive crusade for increased risk awareness and purity in life style can too readily take on the form of cultural imperialism towards conformity. Epidemiologists and the health care movement in general have a mandate to fight disease and premature death; they have no explicit mandate to change culture. 相似文献
134.
WROUGHT TiAl ALLOY DESIGN 总被引:10,自引:3,他引:7
Young Won Kim Materials Manufacturing Directorate Air Force Research Laboratory Wright Patterson AFB OH U. S. A. 《中国有色金属学会会刊》1999,(Z1)
1 INTRODUCTIONSincethefirstmeasurementsofmechanicalpropertiesandoxidationresistanceinabinaryTiAlcastalloyintheearly1950’s,ensuingreports[1-4]haveconfirmedvariouspropertiesbeneficialtohightemperaturestructuralapplicationsincludinglowdensity,excellen… 相似文献
135.
当用户手指碰到连接到电路公共接地的一个触点,或由于手指进入邻近电源线辐射的静电场中而产生的60Hz交流电压时,普通的触摸开关设计都会检测到电阻值下降。但是,如果附近没有电源线,设备由电池供电(如在汽车设备中),或者没有连接到电路公共接地的直流触点时,该怎么办呢? 相似文献
136.
137.
Only at concentrations substantially higher than those likely to occur in human diets did grape tannins have a significant adverse effect on the in virro digestion of bovine serum albumin (BSA). The activities of pepsin and chymotrypsin were at such levels (concentrations greater than 0.1%) significantly reduced. In contrast, that of trypsin increased markedly due to denaturation of BSA by the tannins. Tannin concentrations in excess of 0.5% strongly inhibited the activation of chymotrypsinogen, while the activation of trypsinogen by enterokinase was drastically reduced at concentrations as low as 0.05% due to precipitation of the substrate. BSA digestion was markedly reduced in sequential multizymogen experiments at tannin concentrations of 0.5% but not at 0.1%. 相似文献
138.
Hyeon-cheol YANG Yoon-sup KIM Seong-soo LEE Sang-keun OH Sung-hwa KIM Doo-won CHOI 《测试科学与仪器》2010,1(3)
Surveillance system using active tracking camera has no distance limitation of surveillance range compared to supersonic or sound sensors. However, complex motion tracking algorithm requires huge amount of computation, and it often requires expensive DSPs or embedded processors. This paper proposes a novel motion tracking unit based on different image for fast and simple motion tracking. It uses configuration factor to avoid noise and inaccuracy. It reduces the required computation significantly, so as to be implemented on Field Programmable Gate Array(FPGAs) instead of expensive Digital Signal Processing(DSPs). It also performs calculation for motion estimation in video compression, so it can be easily combined with surveillance system with video recording functionality based on video compression. The proposed motion tracking system implemented on Xilinx Vertex-4 FPGA can process 48 frames per second, and operating frequency of motion tracking unit is 100 MHz. 相似文献
139.
该研究的目的在于探究植物乳杆菌发酵金银花凉茶的工艺条件。以金银花为原料,通过单因素试验和正交试验,研究植物乳杆菌PMO接种量、发酵温度、发酵时间和糖添加量对金银花凉茶发酵过程的影响,并对发酵工艺条件进行优化。结果表明,植物乳杆菌PMO经过驯化过程,其在金银花凉茶中具有优良的增殖活性;金银花凉茶中绿原酸含量受发酵过程影响较小,始终稳定在29.20 mg/g左右;金银花凉茶最佳发酵工艺条件为植物乳杆菌PMO接种量3%、发酵温度37 ℃、发酵时间14 h、糖添加量7%。 相似文献
140.
The position of the artificial lens has an important influence on refractive power calculation. We compared the position of the crystalline lens with that of the artificial lens after cataract surgery by means of Scheimpflug photography. A difference in position of approximately 0.8 mm in the anterior direction could be determined. 相似文献