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This paper presents a stochastic multi-parameters divergence method for online parameter optimization of fractional-order proportional–integral–derivative (PID) controllers. The method is used for auto-tuning without the need for exact mathematical plant model and it is applicable to diverse plant transfer functions. The proposed controller tuning algorithm is capable of adaptively responding to parameter fluctuations and model uncertainties in real systems. Adaptation skill enhances controller performance for real-time applications. Simulations and experimental observations are carried on a prototype helicopter model to confirm the performance improvements obtained by the online auto-tuning of fractional-order PID structure in laboratory conditions. 相似文献
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Jiaqi FAN Changjie YU Kaida REN Wanbing LIN Stella NG Zexin CHEN Xinping LIN Lihan WANG Qifeng ZHU Yuxin HE Jubo JIANG Xianbao LIU Jian'an WANG 《Journal of Zhejiang University. Science. B》2021,22(3):241-247
Aortic stenosis(AS)is a progressive heart valve disease occurring predominantly in older patients.According to a survey in a western country,the prevalence of AS is nearly 6.4%in patients over 75 years old(Carabello and Paulus,2009).Transcatheter aortic valve replacement(TAVR)is an alternative method for AS patients.Previous studies have described how up to 66%of TAVR patients have concomitant baseline kidney dysfunction(Ferro et al.,2015;Gargiulo et al.,2015).The majority of patients can benefit from the TAVR procedure with the recovery of kidney function. 相似文献
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Research Findings: This study explores the beliefs, self-reported practices, and observed practices of Turkish preschool teachers toward children’s peer relationship problems as well as the gap between their beliefs and practices. Five female teachers of 5-year-old children were selected as participants for this multiple case study. Approximately 79 hr of observation was conducted on the children’s daily routines and activities in a natural classroom environment, which specifically included the teachers’ problem-solving strategies while confronting peer relationship problems. The participants were also interviewed regarding their beliefs and strategies for solving peer relationship problems. The findings of this qualitative investigation indicated that the teachers’ beliefs and self-reported practices included both teacher- and child-related factors. However, the observed practices included several teacher-initiated strategies; child-initiated strategies appeared, albeit less than teacher-initiated ones. This affirms the teachers’ stress on children’s role in managing peer problems. Although some of the teacher practices and beliefs were consistent, certain inconsistencies may indicate the presence of external constraints. Practice or Policy: The results of this study highlight the importance of teacher education programs providing preservice and in-service teachers with the knowledge and skills required to understand children’s peer relationships, guide their interactions, and apply appropriate intervention strategies for various peer relationship problems. 相似文献
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Bahar Ünlü Gül Ouzhan
zcan Serdar Doan Abdullah Arpaci 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2022,32(3)
IntroductionAutoverification (AV) is a postanalytical tool that uses algorithms to validate test results according to specified criteria. The Clinical and Laboratory Standard Institute (CLSI) document for AV of clinical laboratory test result (AUTO-10A) includes recommendations for laboratories needing guidance on implementation of AV algorithms. The aim was to design and validate the AV algorithm for biochemical tests.Materials and methodsCriteria were defined according to AUTO-10A. Three different approaches for algorithm were used as result limit checks, which are reference range, reference range ± total allowable error, and 2nd and 98th percentile values. To validate the algorithm, 720 cases in middleware were tested. For actual cases, 3,188,095 results and 194,520 reports in laboratory information system (LIS) were evaluated using the AV system. Cohen’s kappa (κ) was calculated to determine the degree of agreement between seven independent reviewers and the AV system.ResultsThe AV passing rate was found between 77% and 85%. The highest rates of AV were in alanine transaminase (ALT), direct bilirubin (DBIL), and magnesium (Mg), which all had AV rates exceeding 85%. The most common reason for non-validated results was the result limit check (41%). A total of 328 reports evaluated by reviewers were compared to AV system. The statistical analysis resulted in a κ value between 0.39 and 0.63 (P < 0.001) and an agreement rate between 79% and 88%.ConclusionsOur improved model can help laboratories design, build, and validate AV systems and be used as starting point for different test groups. 相似文献
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Zeynep Hatipoğ Sümer Gül Aydin 《International journal for the advancement of counseling》1999,21(4):335-347
The present article deals with the incidence of violence cases inTurkish schools. A review of research based on published research reports andunpublished M.Sc. and Ph.D. dissertations is presented and basic lines of researchare discussed. Special emphasis was placed upon culturally specific issues,besides the culturally determined attitudes of parents and teachers. The need for anationwide system for the prevention of violence and corporal punishment wasemphasized. 相似文献
18.
我国女子体操运动员运动损伤情况的调查与分析 总被引:12,自引:0,他引:12
竭晓安 《北京体育大学学报》2001,24(1):56-57
对近十年来我国女子体操运动员的运动损伤情况进行了调查 ,找出了运动损伤的主要原因、常见部位及主要发生时期 ,对我国女子体操运动员运动损伤的预防具有重要意义。 相似文献
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The purpose of this study is to describe the strategies used by a mother with a child with autism during games activities with peers to provide the child with social skills. The research method of this study is ‘a qualitative single‐subject case study’. The participants in this research are a mother and her 9‐year‐old child with autism, one brother and three typically developing peers. The research data were collected through field notes, interviews, audio and videotape recordings during natural interactions between the mother and her child. The strategies the mother used were analysed using video records during games activities in a natural park. The interactions of the mother with her child were examined in the context of a hide‐and‐seek game. Micro‐ethnographic‐analysis techniques were used in the analysis of the video records. According to the research data, it was found that the mother with a child with autism made extensive use of 13 different verbal strategies and seven different non‐verbal strategies. It was observed that the mother guided her child and the group during the hide‐and‐seek game, arranged the environment of the games, carried out routine activities both at the beginning and at the end of the games and arranged the games in accordance with the abilities and preferences of the child. These applications bear a resemblance to the model of integrated game groups. As a result, the data from the present research reveal that a mother having a child with autism acts as a guide during the games and uses verbal and non‐verbal interaction strategies in this guidance process and by doing so contributes to the process of participation in the games by the child with autism and in the child's social interaction with his peers. 相似文献
20.
Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively. 相似文献