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111.
In this paper, an adaptive TSK-type CMAC neural control (ATCNC) system via sliding-mode approach is proposed for the chaotic symmetric gyro. The proposed ATCNC system is composed of a neural controller and a supervisory compensator. The neural controller uses a TSK-type CMAC neural network (TCNN) to approximate an ideal controller and the supervisory compensator is designed to guarantee system stable in the Lyapunov stability theorem. The developed TCNN provides more powerful representation than the traditional CMAC neural network. Moreover, all the control parameters of the proposed ATCNC system are evolved in the Lyapunov sense to ensure the system stability with a proportional–integral (PI) type adaptation tuning mechanism. Some simulations are presented to confirm the validity of the proposed ATCNC scheme without the occurrence of chattering phenomena. Further, the proposed PI type adaptation laws can achieve faster convergence of the tracking error than that using integral type adaptation laws in previous published papers. 相似文献
112.
Florence Hsu 《中外文化交流(英文版)》2011,(6):23-25
<正>The Silk Road has always remained an exotic region for the people from around the worldThanks to its geographic location,the Silk Road provided perfect oppor... 相似文献
113.
This study explored the effects of a 6-week psychological displacement paradigm in diary-writing (PDPD) intervention on alexithymia and social connectedness in Taiwanese college athletes at the individual and interpersonal levels. The sample comprised 87 participants (Mage = 19.80 ± 0.75 years). After a pretest, the individual writing group engaged in individual and interpersonal PDPD twice a week for 6 consecutive weeks. A posttest was conducted after the interventions, and a follow-up test was conducted 2 months later. Both the individual and interpersonal writing groups scored lower than did the control group on difficulty identifying feelings and difficulty describing feelings in the posttest, and the effects persisted at follow-up. Moreover, PDPD contributed to an increase in social connectedness. This study provided evidence of the effects of individual and interpersonal PDPD on athletes' emotion control and emotion regulation. 相似文献
114.
Chung Bing Yang Chung-Chief Chuang Chung Sen Kuo Chin Hsing Hsu 《Journal of sports sciences》2013,31(5):446-451
AbstractWe investigated the effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) concentrations. Eighteen male participants completed two different exercise sessions with intensities of 25% and 65% maximal aerobic capacity (VO2max). In addition to the energy expenditure during exercise sessions being measured, blood samples were collected before exercise, and immediately, at 24 h, and at 48 h post-exercise to analyse sOB-R, leptin and insulin levels. At 24 h post-exercise, sOB-R and leptin concentrations at the 65% VO2max were significantly different from those at the 25% VO2max. Leptin levels at 48 h post-exercise were also significantly lower for the 65% VO2max than for the 25% VO2max (P < 0.01). In the 65% VO2max session, the energy expenditure during exercise was significantly associated with leptin concentrations at 24 h and 48 h and sOB-R concentrations at 24 h post-exercise. However, no correlations were found between sOB-R and leptin at the three post-exercise time points. In conclusion, an acute bout of exercise with 920 kcal of output resulted in an increase in sOB-R levels at 24 h post-exercise. However, the changes in sOB-R levels due to an acute bout of exercise might not contribute to the delayed decrease observed for leptin. 相似文献
115.
116.
Tiago Roux Oliveira Alessandro Jacoud Peixoto Liu Hsu 《Journal of The Franklin Institute》2012,349(4):1397-1415
This paper addresses the design of a sliding mode based extremum-seeking controller for a class of single-input–single-output (SISO) uncertain nonlinear systems with unmatched and state-dependent strong nonlinearities. We demonstrate that it is possible to achieve an arbitrarily small neighborhood of the desired optimal point using only output-feedback. The key idea is the combination of a periodic switching function with a norm state observer. As an important advantage, we show that the proposed scheme achieves extremum-seeking for all initial conditions, i.e., the real-time optimization algorithm has global convergence properties. An application to a simple nonderivative optimizer illustrates the viability of the proposed approach. 相似文献
117.
Pei-Ling Hsu 《Journal of Science Education and Technology》2018,27(6):481-491
Internships in science research settings have received increasing attention as a means of helping students construct appropriate understandings, practices, tools, and language in scientific activities. To advance student–scientist partnerships beyond the status quo, the study aimed to investigate how cogenerative dialogs (cogens) may help high school students and scientists identify and address challenges collectively. The analysis identified nine major challenges discussed during cogens: (1) the quality and progress of scientific practice in laboratories, (2) the quality of scientists’/assistants’ instructions in classrooms, (3) the quality of student participation in classrooms and homework, (4) students’ absences, including arriving late or leaving early, (5) the quality of administrative support, (6) preparation for scientific presentations, (7) the process of deciding project topics, (8) students’ peer interactions and communication, and (9) students’ physiological needs. The three most salient challenges were “the quality and progress of scientific practice in laboratories” (39%), “the quality of scientists’/assistants’ instructions in classrooms” (20%), and “the quality of student participation in classrooms and homework” (17%). The study shows that cogens allowed students and scientists to agree on teaching modifications that positively influenced teaching and learning processes during the internship, such that issues were reduced from the beginning to the closing stages. Importantly, the challenges and solutions identified by students and scientists in this study provide accounts of first-hand experience as well as insights to aid program directors or coordinators in designing a learning environment that can foster effective practice for internships by avoiding the issues identified in the study. 相似文献
118.
Working with scientists has been suggested as an effective way for high-school students to learn authentic science. However, little research has involved students’ perceptions of science learning environments in a university internship. This study drew on the theoretical framework of community of practice with cogenerative dialogues to design an internship program that aims to build a constructivist internship for students. Students who learned science in the internship program developed stronger constructivist learning perceptions than those who learned science in school. Specifically, students perceived that they had more opportunities to think independently of the instructors and other students. Three effective principles for program design are: (a) high school students conduct open-inquiry projects with the support of scientists; (b) high school students and scientists conduct cogenerative dialogues regularly to address issues and share experiences; and (c) high school students present their project proposals and scientific findings at open house events. Implications of the results are discussed. 相似文献
119.
According to the information including type material with regard to Raphiolepis
major Card. and R. indica (L.) Lindl., the morphological differences between these two
closely related taxa are largely quantitative, i.e., the former has larger leaves, flowers
and fruits, and longer petioles and pedicels than the latter. But since these characteri-
stics are rather variable, they can hardly be proven to be sound in separating these two
taxa as distinct.
By using methods of quantitative analysis with scatter diagrams on herbarium ma-
terials, we have found that the characteristics used to discriminate the two taxa either
tend to display continuous variational patterns, or vary at random. Both eases suggest
that the morphological variations of individual sample plants are probably due to the dif-
ferent modes of growth or development of plants in response to varied environments.
Since these two taxa are taxonomically inseparable from each other as a whole, it seems
advisable to treat them as one single species. Thus, the lately published R. major Card.should be reduced to a synonym of R. indica (L.) Lindl. 相似文献
120.
This paper, which consists of a part of pertinent data obtained through a cri-
tical revision of the genus Lonicera of China. discusses 28 noteworthy species and infra-
specific taxa. Among them, 3 subspecies and 1 variety are new grades and combinations. Be-sides, 31 species, 11 varieties and 6 forms have been reduced to synonyms. 相似文献