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The purpose of this paper is to examine diminish switching losses in a solar energy conversion system in order to utilise the full efficiency of a solar panel.

In this paper, a boost converter and a resonant DC link (RDCL) inverter are controlled by a microcontroller. The maximum power point tracker (MPPT) algorithm implemented for boost converter supplies to track maximum power point of solar panel. The Class D full-bridge resonant inverter (RI) that is considered to be supplied by boost converter is modeled and zero voltage switching operation is performed by controlling the inverter with sinusoidal pulse width modulation (SPWM) control scheme. The control algorithm is managed with a feedback detecting the current of the boost converter and the zero voltage levels of capacitor voltage in the resonant circuit.

There are several control techniques have been proposed to reduce switching losses and harmonic contents in conventional or RDCL inverters. Solar panels are used in low power applications among other renewable energy sources. By considering that the efficiency parameter of an actual solar panels is around 14∼17 per cent, the switching losses occurred in energy conversion systems causes the efficiency are reduced.

The proposed approach has been decreased the switching power losses owing to resonant DC link inverter while the developed MPPT algorithm provides to generate maximum power. This paper introduces a novel soft switching technique in solar energy applications in order to maximise the possible efficiency.

The beta coefficient used for the cost of equity calculation is at the heart of the valuation process. This study conducts comparative analyses of the classical capital asset pricing model (CAPM) and downside CAPM risk parameters to gain further insight into which risk parameter leads to better performing risk measures at explaining stock returns.

The study conducts a comparative analysis of 16 risk measures at explaining the stock returns of 4531 companies of 20 developed and 25 emerging market index for 2000–2018. The analyses are conducted using both the global and local indices and both USD and local currency returns. Calculated risk measures are analyzed in a panel data setup using a univariate model. Results are investigated in country-specific and model-specific subsets.

The results show that (1) downside betas are better than CAPM betas at explaining the stock returns, (2) both risk measure groups perform better for emerging markets, (3) global downside beta model performs better than global beta model, implying the existence of the contagion effect, (4) high significance levels of total risk and unsystematic risk measures further support the shortfall of CAPM betas and (5) higher correlation of markets after negative shocks such as pandemics puts global CAPM based downside beta to a more reliable position.

The data are limited to the index securities as beta could be time varying.

Results overall provide insight into the cost of equity calculation and emerging market assets valuation.

The framework and methodology enable us to compare and contrast CAPM and downside-CAPM risk measures at the firm level, at the global/local level and in terms of the level of market development.

While the current knowledge in the field of educational leadership and management (EDLM) has been primarily based on research produced in English-speaking Western societies, there have been significant efforts by other societies to contribute to the knowledge production, especially during the past decade. The purpose of this paper is to identify the contribution of Turkey to the international EDLM literature by investigating the topical focus, conceptual frameworks and research designs of papers published by EDLM scholars from Turkey.

Descriptive content analysis method was employed to examine 315 empirical, review, conceptual and commentary papers published by Turkish scholars in core educational administration and Web of Science journals. The time period of the review left open-ended. However, in practical terms, it begins in the year 1994 when the first article from Turkey was published in any of the selected sources and ends at the end of 2018. Information relevant to the research was extracted from each article and was coded to facilitate quantitative analysis. Using Excel software, descriptive statistics including frequencies and percentages were provided for each research question.

Results show that Turkish EDLM scholars mostly rely on survey based quantitative research approach, employing advanced statistical techniques in the analysis of the data. However, mixed method and qualitative studies are relatively less common. Organizational behavior, school leadership and emotions stand out as most frequently used topics, while Turkish scholars are not interested in analyzing the educational outcomes such as student achievement and school improvement. Consistent with the findings related to topical foci, a large number of those who were interested in correlational studies examined the relationship between leadership roles and organizational behaviors.

The data set only included journal articles and excluded conference proceedings, books and theses/dissertations. Nevertheless, the authors believe this review adds significantly to previous reviews of local EDLM journals conducted by Turkish scholars. The authors concluded that the Turkish scholars should direct their future research to exploring and better understanding the practices of Turkish principals in schools by: diversifying their research topics; incorporating more qualitative and mixed-method designs; and taking into account specific features of the culture and educational system in Turkey.

Based on the current higher education context, reducing scholars’ teaching load, diversifying research funding opportunities, and modifying access to tenure tracks seem necessary interventions to support EDLM research with strong ties to practice and to the sociocultural context. In addition, policy changes aiming professionalization of administrative positions and establishing some forms of formal training for school principalship are needed. Such changes can help transfer the knowledge produced by the Turkish EDLM researchers to the practice and provide solutions to problems related to school administration.

This paper will add to recent effort to identify how a developing nation outside Western perspective approaches the field, and contributes to the global knowledge base.

Green destinations are places that are important for the sustainable realization of tourism. In addition to the design of these destinations, the management also emerges as an issue that needs to be emphasized. As a matter of fact, stakeholders and their relations with each other and other issues are an important element in the management of green destinations. In this context, in the study, issues such as management of green destinations, stakeholders, relations between stakeholders, education and green destination management in Türkiye are discussed. Finally, some suggestions have been presented within the framework of the topics discussed.

The main purpose of this study is to detect homogeneous housing market areas among 196 districts of 5 major cities of Turkey in terms of house sale price indices. The second purpose is to forecast these 196 house sale price indices.

In this paper, the authors use the monthly house sale price indices of 196 districts of 5 major cities of Turkey. The authors propose an autoregressive (AR) model-based fuzzy clustering approach to detect homogeneous housing market areas and to forecast house price indices.

The AR model-based fuzzy clustering approach detects three numbers of homogenous property market areas among 196 districts of 5 major cities of Turkey where house sale price moves together (or with similar house sales dynamic). This approach also provides better forecasting results compared to standard AR models by higher data efficiency and lower model validation and maintenance effort.

In this study, the authors could not use any district-based socioeconomic and consumption behavioral indicators and any discrete geographical and property characteristics because of the data limitation.

The finding of this study would help property investors for establishing more effective property management strategies by taking different geographical location conditions into account.

From the government side, knowing future rises, falls and turning points of property prices in different locations can allow the government to monitor the property price changes and control the speculation activities that cause a dramatic change in the market.

There is no previous research paper focusing on neighborhood-based clusters and forecasting house sale price indices in Turkey. At this point, it is the first academic study.

School principals should create a positive school climate through instructional leadership behaviors and support teacher autonomy to reach their ultimate goals. This study examines the relationship between the instructional leadership behaviors of school principals and teacher autonomy, testing the mediating role of school climate and the moderator role of teacher seniority.

This cross-sectional study tests the relationships between the variables with structural equation modeling. By stratified sampling method, research data from 739 teachers in six central districts of Ankara during the 2022–2023 academic year.

Results showed that school principals' instructional leadership behaviors, teacher autonomy, and perceptions of school climate were above average. The study also indicates that the instructional leadership behaviors of school principals are positive and significant predictors of teacher autonomy and school climate and that school climate is a positively significant predictor of teacher autonomy. Moreover, school climate partially mediates the relationship between instructional leadership and teacher autonomy, and teacher seniority has a moderator role.

This study is limited to the opinions of the teachers working in the official primary, secondary and general high schools in the districts of Ankara in the 2022–2023 academic year on the instructional leadership of the school principals, the teachers' perceptions of autonomy and the school climate. It has been observed that there is a relationship between the instructional leadership behaviors of school principals and teacher autonomy. It can be said that the instructional leadership behaviors of school principals support teachers to exhibit autonomous behaviors in instructional strategies and processes, curriculum, classroom management, professional development and communication.

It is seen that the instructional leadership behaviors of school principals affect teacher autonomy through school climate. It can be said that with the instructional leadership behaviors of school principals, the school climate is more democratic, success-oriented, sincere, supportive of teacher leadership and transforming conflicts into an opportunity for school development, thus affecting teachers' areas of autonomy. We can say that with the development of teachers' autonomy, more effective instructional strategies and instructional processes are developed, the curriculum is transferred with more permanent teaching techniques, professional communication is transformed into collective actions and more comprehensive studies are planned and implemented.

This study will extend the literature by revealing the complex link between instructional leadership, teacher autonomy, school climate and teacher seniority. Furthermore, this study estimates how these complex interactions emerge in non-western cultures with centralized educational structures.