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This paper aims to determine factors affecting health-care utilization of immigrants living in North of Turkey and make a case assessment about this factors and general health status of immigrants.

This study was conducted in accordance with the principles of descriptive research. The data of the study were collected by using questionnaire consisting of 33 questions that include socio-demographic specifications, use of health services and health perception level.

This study was conducted with 360 immigrants. Participants, of which 61.9% were female. Immigrants who are young, female, married, have low education, have chronic illnesses, and have been in hospital before, have a better use of health services.

Immigration experiences of immigrants and their lack of equal opportunities to access health services in the community lead them to use health services at a low level.

Additive manufacturing became the most popular method as it enables the production of light-weight and high-density parts in effective way. Selective laser melting (SLM) is preferred by means of producing a component with good surface quality and near-net shape even if it has complex form. Titanium alloys have been extensively used in engineering covering a variety of sectors such as aeronautical, chemical, automotive and defense industry with its unique material properties. Therefore, the purpose of this review is to study the tribological behavior and surface integrity that reflects the thermal and mechanical performances of the fabricated parts.

This paper is focused on the tribological and surface integrity aspects of SLM-produced titanium alloy components. It is aimed to outline the effect of SLM process parameters on tribology and surface integrity first. Then, thermal, thermal heat, thermomechanical and postprocessing surface treatments such as peening, surface modification and coatings are highlighted in the light of literature review.

This work studied the effects of particle characteristics (e.g. size, shape, distributions, flowability and morphology) on tribological performance according to an extensive literature survey.

This study addresses this blind spot in existing industrial-academic knowledge and goals to determine the impact of SLM process parameters, posttreatments (especially peening operations) and particle characteristics on the SLMed Ti-based alloys, which are increasingly used in biomedical applications as well as other many applications ranging from automobile, aero, aviation, maritime, etc. This review paper is created with the intention of providing deep investigation on the important material characteristics of titanium alloy-based components, which can be useful for the several engineering sectors.

The nickel-based alloys Inconel 625 and Inconel 718 stand out due to their high strength and corrosion resistance in important industries like aerospace, aviation and automotive. Even though they are widely used, current techniques of producing materials that are difficult to cut pose several problems from a financial, ecological and even health perspective. To handle these problems and acquire improved mechanical and structural qualities, laser powder bed fusion (LPBF) has been widely used as one of the most essential additive manufacturing techniques. The purpose of this article is to focus on the state of the art on LPBF parts of Inconel 625 and Inconel 718 for microstructure, mechanical behavior and postprocessing.

The mechanical behavior of LPBF-fabricated Inconel is described, including hardness, surface morphology and wear, as well as the influence of fabrication orientation on surface quality, biocompatibility and resultant mechanical properties, particularly tensile strength, fatigue performance and tribological behaviors.

The postprocessing techniques such as thermal treatments, polishing techniques for surface enhancement, mechanical and laser-induced peening and physical operations are summarized.

The highlighted topic presents the critical aspects of the advantages and challenges of the LPBF parts produced by Inconel 718 and 625, which can be a guideline for manufacturers and academia in practical applications.

The main purpose of this work is to explore the erosion wear characteristics of additively manufactured aluminium alloy. Additive manufacturing (AM), also known as three-dimensional (3D) manufacturing, is the process of manufacturing a part designed in a computer environment using different types of materials such as plastic, ceramic, metal or composite. Similar to other materials, aluminum alloys are also exposed to various wear types during operation. Production efficiency needs to be aware of its reactions to wearing mechanisms.

In this study, quartz sands (SiO₂) assisted with oxide ceramics were used in the slurry erosion test setup and its abrasiveness on the AlSi10Mg aluminum alloy material produced by the 3D printer as selective laser melting (SLM) technology was investigated. Quartz was sieved with an average particle size of 302.5 µm, and a slurry environment containing 5, 10 and 15% quartz by weight was prepared. The experiments were carried out at the velocity of 1.88 (250 rpm), 3.76 (500 rpm) and 5.64 m/s (750 rpm) and the impact angles 15, 45 and 75°.

With these experimental studies, it has been determined that the abrasiveness of quartz sand prepared in certain particle sizes is directly related to the particle concentration and particle speed, and that the wear increases with the increase of the concentration and rotational speed. Also, the variation of weight loss and surface roughness of the alloy was investigated after different wear conditions. Surface roughness values at 750 rpm speed, 10% concentration and 75° impingement angle are 0.32 and 0.38 µm for 0 and 90° samples, respectively, with a difference of approximately 18%. Moreover, concerning a sample produced at 0°, the weight loss at 250 rpm at 10% concentration and 45° particle impact angle is 32.8 mg, while the weight loss at 500 rpm 44.4 mg, and weight loss at 750 rpm is 104 mg. Besides, the morphological structures of eroded surfaces were examined using the scanning electron microscope to understand the wear mechanisms.

The researchers verified that this specific coating condition increases the slurry wear resistance of the mentioned steel. There are many studies about slurry wear tests; however, there is no study in the literature about the quartz sand (SiO₂) assisted slurry-erosive wear of AlSi10Mg alloy produced with AM by using SLM technology. This study is needed to fill this gap in the literature and to examine the erosive wear capability of this current material in different environments. The novelty of the study is the use of SiO₂ quartz sands assisted by oxide ceramics in different concentrations for the slurry erosion test setup and the investigations on erosive wear resistance of AlSi10Mg alloy manufactured by AM.

Twitter usage during Gezi Park Protests, a significant large-scale connective action, is analyzed to reveal meaningful findings on individual and group tweeting characteristics. Subsequent to the Arab Spring in terms of its timing, the Gezi Park Protests began by the spread of news on construction plans to build a shopping mall at a public park in Taksim Square in Istanbul on May 26, 2013. Though started as a small-scale local protest, it emerged into a series of multi-regional social protests, also known as the Gezi Park demonstrations. The paper aims to discuss these issues.

The authors sought answers to three important research questions: whether Twitter usage is reflective of real life events, what Twitter is actually used for, and is Twitter usage contagious? The authors have collected streamed data from Twitter. As a research methodology, the authors followed social media analytics framework proposed by Fan and Gordon (2014), which included three consecutive processes; capturing, understanding, and presenting. An analysis of 54 million publicly available tweets and 3.5 million foursquare check-ins, which account to randomly selected 1 percent of all tweets and check-ins posted from Istanbul, Turkey between March and September 2013 are presented.

A perceived lack of sufficient media coverage on events taking place on the streets is believed to result in Turkish protestors’ use of Twitter as a medium to share and get information on ongoing and planned demonstrations, to learn the recent news, to participate in the debate, and to create local and global awareness.

Data collection via streamed tweets comes with certain limitations. Twitter restricts data collection on publicly available tweets and only allows randomly selected 1 percent of all tweets posted from a specific region. Therefore, the authors’ data include only tweets of publicly available Twitter profiles. The generalizability of the findings should be regarded with concerning this limitation.

The authors conclude that Twitter was used mainly as a platform to exchange information to organize street demonstrations.

The authors conclude that Twitter usage reflected Street movements on a chronological level. Finally, the authors present that Twitter usage is contagious whereas tweeting is not necessarily.

This study aims to obtain the lowest surface roughness (Ra) and drill bit adhesion values (AV) depending on the change in control factors (cutting speed-Vc, feed rate-f and drill bit-D) during drilling of the Al 5083 H116 alloy. Low roughness values increase the fatigue strength of the final part and affect tribological properties such as lubrication and friction. In the machining of ductile materials, the AV increases the Ra value and negatively affects the tool life.

Drilling tests were conducted using Taguchi L16 orthogonal array. The experimental measurement findings for Ra and AV were adjusted utilizing the Grey Relational Analysis (GRA), the Response Surface Method (RSM) and Artificial Neural Networks (ANN) to generate prediction values. SEM detected drill-tip adhesions and chip morphology and they were analyzed by EDX.

Ra and AV increased as the f increased. Vc affects AV; 86.04% f on Ra and 54.71% Vc on AV were the most effective control parameters. After optimizing Ra and AV using GRA, the f is the most effective control factor. Vc: 120 m/min, f: 0.025 mm/rev and D2 were optimal. ANN predicted with Ra 99.6% and AV 99.8% accurately. Mathematical models are obtained with RSM. The increase in f increased AV, which had a negative effect on Ra, whereas the increase in Vc decreased the adhesion tendency. With the D1 drill bit with the highest flute length, a relatively lower Ra was measured, as it facilitates chip evacuation. In addition, the high correlations of the mathematical models obtained indicate that the models can be used safely.

The novelty of this study is to determine the optimum drilling parameters with GRA and ANN for drilling the necessary holes for the assembly of ammunition wing propulsion systems, especially those produced with Al 5083 H116 alloy, with rivets and bolts.

This study aims to provide preliminary information to the investor by determining which indices co-movement, with the data mining method.

In this context, data sets containing daily opening and closing prices between 2001 and 2019 have been created for 11 stock market indexes in the world. The association rule algorithm, one of the data mining techniques, is used in the analysis of the data.

It is observed that the US stock market indices take part in the highest confidence levels between association rules. The XU100 stock index co-movement with both the European stock market indices and the US stock indices. In addition, the Hang Seng Index (HSI) (Hong Kong) takes part in the association rules of all stock market indices.

The important issue for data sets is that the opening/closing values of the same day or the previous day are taken into account according to the open or closed status of other stock market indices by taking the opening time of the stock exchange index to be created. Therefore, data sets are arranged for each stock market index, separately. As a result of this data set arranging process, it is possible to find out co-movements of the stock market indexes. It is proof that the world stock indices have co-movement, and this continues as a cycle.

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.

Female leader is a major topic in the male of today that’s hardly getting attention. World today needs women in more positions of leadership. Today’s organizations need effective and agile leaders who understand the complexities of the rapidly changing global environment. This situation requires urgent attention as the world needs female as well as male characteristics to address global issues. Women represent half of the modern world’s abilities and population. They are important for economic and social prosperity for the world. Women carry a viewpoint that respects not only competitiveness but also organizational and team cooperation. Their female ideals are a functioning structure of new, cooperative and open economy. Eventually, the leadership of women will not only boost business, family and culture, but also the environment that will become more prosperous and peaceful as a result. In today’s modern world many researches are conducted on global, social and cultural forces, such as globalization, e-commerce, changing markets, the spread of technology and the need for teamwork, alliances and partnerships, show a high need for women leaders. But what is the role and leadership style of female leaders here? In this context, the purpose of this study is to discuss the leadership styles and what kind of leadership style female managers exhibit in line with the literature. The research showed that female managers have more agile leadership qualities and the authors suggested that female leaders should be brought forward for the opportunity to lead others toward a better future.

This study aimed to examine the prospective role played by perceived environmental uncertainty in the strategy‐performance linkage among SMEs in China, Turkey, and the USA.

The strategic group level of analysis was employed. Generic strategy, environmental uncertainty, and performance were measured by previously validated scales.

The combination strategy‐performance linkage was supported in Turkey and the USA. In China, the highest performing strategic group emphasized a focus orientation accompanied by neither cost leadership nor differentiation, and the lowest performing group was comprised of low cost businesses.

This study supported the combination strategy thesis in the USA and Turkey. In China, conceptualizations of strategy appear to be more complex. High performing businesses emphasized a focus strategy, but not necessarily in concert with either cost leadership or differentiation.

Firms in the USA place a great deal of emphasis on uniqueness and individuality, translating into approaches based on differentiation and innovation. However, attempting to control costs and differentiate without a defined niche leaves a firm vulnerable to larger, more experienced competition.

This study addresses the death of strategy‐performance investigations in developing nations. Findings presented run counter to the notion that successful businesses in emerging economies emphasize cost leadership vis‐à‐vis differentiation. Conventional wisdom suggests that high performers tend to perceive greater certainty about their environments. The present analysis not only rejected this finding, but suggests that the opposite might be true.