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11.
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   
12.
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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14.
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   
15.

Introduction

Hemolysis can occur during sample collection, handling and transport. It is more frequent when the non-laboratory staff performs sampling. The aim of this study was to assess nurses’ knowledge on the causes of hemolysis and consequential impact on the laboratory tests results. Additionally, the differences in knowledge, related to work experience, professional degree and previous education about hemolysis were explored.

Materials and methods

An anonymus survey, containing 11 questions on demographics, causes of hemolysis, its impact on biochemical parameters and nurses’ attitude towards additional education in preanalytics, was conducted in four Croatian hospitals. The answers were compared by Chi-squared and Fischer exact test.

Results

In total, 562 survey results were collected. Majority of nurses declared familiarity with the term “hemolysis” (99.6%). There were 77% of correct answers regarding questions about the causes of hemolysis, but only 50% when it comes to questions about interference in biochemical tests. The percentage of correct answers about causes was significantly lower (P = 0.029) among more experienced nurses, and higher (P = 0.027) in those with higher professional degree, while influence of previous education was not significant. Also, higher percentage of correct answers about interferences was encountered in nurses with longer work experience (P = 0.039). More than 70% of nurses declared that additional education about preanalytical factors would be beneficial.

Conclusion

Croatian nurses are familiar with the definition of hemolysis, but a lack of knowledge about causes and influence on laboratory test results is evident. Nurses are eager to improve their knowledge in this field of preanalytical phase.Key words: hemolysis, nurses, survey, preanalytical phase  相似文献   
16.
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   
17.
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   
18.
In this study, the use of inquiry methods, learning cycles, a conceptual change model and analogy in creating alternative science texts was discussed. An alternative text on the topic of acids and bases was created by integrating the methods and models discussed in this paper. The alternative text and a sample of a traditional text taken from a textbook, which is still used in Turkish high schools, were given to two groups, totaling 42 pre-service teachers—the alternative text was given to an experimental group and the traditional text to a control group—in an experimental setting and their understandings of acids and bases were compared. In addition, in the second step of the study, the pre-service teachers read both texts and indicated their preferences in terms of interest, understandability and helpfullness.  相似文献   
19.
This study explored what kind of mathematics is needed in cabinetmakers’ everyday work and how problem solving is intertwined in it. The informants of the study were four Finnish cabinetmakers and the data consisted of workshop observations, interviews, photos, pictures and sketches made by the participants during the interviews. The data was analysed using different qualitative techniques. Even though the participants identified many areas of mathematics that could be used in their daily work, they used mathematics only if they were able to. The cabinetmakers’ different mathematical skills and knowledge were utilized to their skill limit. Cabinetmakers were found to constantly face problem solving situations along with the creative processes. Being able to use more advanced mathematics helped them to solve those problems more efficiently, without wasting time and materials. Based on the findings, the paper discusses the similarities and differences between problem solving and creative processes. It is suggested that the combination of craftsmanship, creativity, and efficient problem solving skills together with more than basic mathematical knowledge will help cabinetmakers in adapting and surviving in future unstable labour markets.  相似文献   
20.
在图书市场,20%的畅销品种产生80%的效益,畅销书对市场的影响已是不争的事实。    相似文献   
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