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The aim of this study is to examine the effect of school administrators’ empowering leadership behaviors on the psychological contract perceptions of secondary education institution (high school) teachers. The population of the study consists of 2,878 teachers who were working at 47 high schools located in central Elazığ during the 2019-2020 school year. The sample of the study consisted of 470 teachers selected from 12 schools using the stratified sampling method. Data were collected by using the "Scale for School Administrator Compliance with Psychological Contract" developed by Koçak (2016) and the “Scale for Teacher Compliance with Psychological Contract". Teacher perceptions of the level to which school administrators displayed empowering leadership behaviors were measured by using the Empowering Leadership Behaviors Scale developed by Konczak and Stelly and Trusty (2000) and adapted to Turkish by Aras (2013). It was found that teachers had high perceptions of school administrator compliance with psychological contract (SACPC) and that they also had a high level of compliance with psychological contract (STCPC). Additionally, it was found that teacher perceptions of school administrators displaying empowering leadership behaviors (OYGLD) were also high. Perceptions of teachers who had been working for 7-11 years in the same school regarding school administrator compliance with psychological contract were higher than those of teachers who had been working in the same institution for 2-6 years. Moderately positive and significant relationships were found between the Scale for School Administrator Compliance with Psychological Contract (SACPC), the Scale for Teacher Compliance with Psychological Contract (STCPC) and its subdimensions, and the Empowering Leadership Behaviors Scale (ELBS). The variables of deciding on one’s own, knowledge sharing and innovative performance did not have a significant impact.

The use of plant materials as the source of oil and functional foods is becoming more important with the new trends and scientific research. In this study, fig (Ficus carica) seed, which is a rarely found, seed and its oil, have been studied to determine the phytochemical properties for possible applications. Fig seeds were obtained from Aydın, Turkey. The oil was extracted by the cold press method. The seeds were analyzed for oil yield, protein, ash, ash insoluble in hydrochloric acid and trace elements. The oil was evaluated for fatty acid, sterol compositions by GC and the volatiles were analyzed with GCMS, tocopherols analyzed by HPLC, total phenolic content and antioxidant activity were determined spectrophotometrically. The oil was also evaluated for free fatty acid (FFA), refractive index (RI), peroxide (PV) and p-anisidine value. The results showed that F. carica has 22.7% oil yield and was characterized by linolenic (41.27%), linoleic (30.06%), and oleic acids (18.10%). Total phenolics were 79.5 mg GAE/100 g, and nine different sterol components were analyzed and β-sitosterol was at the highest rate. Theα-β-γ-δ tocopherol content was 6.088, 0.18, 634, 18 mgkg-1, respectively. Antioxidant capacity was 52.54%. Fenchone, cymene, styrene d-limonene, linalool, camphor were found as important volatiles. Quality parameters were FFA (% oleic acid) 0.90, RI (40 oC) 1.4721, PV (meq O2/kg oil) 2.2, p-anisidine 2.22. As a result, F. carica oil can be an alternative oil source and a good option for functional foods with their rich contentof phytochemicals. For the future, more studies need to be done for both the seeds and the oil for further applications. Keywords Ficus carica seed, cold-pressed oil, fig seed, phytochemical properties

In this study, the gas piston actuated opening-closing trunk lid mechanisms used in passenger cars are investigated theoretically and experimentally. First, the position analysis of the mechanism which is a four-bar linkage has been carried out. Then the quasi-static analyzes according to the principle of virtual work have been made, and so the hand force, one of the most important parameters in terms of ergonomics, required for opening and closing the trunk lid has been calculated. In order to verify this developed model, the hand force has been determined also experimentally, performing the physical tests on an existing vehicle at Turkish Automobile Factory Inc. (TOFAŞ). Eventually, it is observed that the results obtained from mathematical model and the experimental measurements are compatible each other. This established model will provide convenience for manufacturers to determine the hand force for different model of vehicles.

Bu çalışmada binek araçlarda kullanılan gazlı pistonlu bagaj kapağı açma-kapama mekanizmaları teorik ve deneysel olarak incelenmiştir. Öncelikle bir dört çubuk mekanizması olduğu açıkça görülen bu mekanizmanın konum analizi yapılmıştır. Daha sonra virtuel işler ilkesine göre sanki-statik analizler yapılmış ve böylece ergonomi açısından en önemli parametrelerden biri olan kapağı açma ve kapama için gerekli el kuvveti hesaplanmıştır. Kurulan bu modeli doğrulamak için Türk Otomobil Fabrikası A. Ş. (TOFAŞ)’ de mevcut olan bir araç üzerinde fiziksel testler yapılarak el kuvveti deneysel olarak da tespit edilmiştir. Nihayetinde, matematiksel modelden elde edilen sonuçlar ile deneysel ölçümlerden elde edilen sonuçların uyumlu olduğu görülmüştür. Kurulan bu model farklı model araçlar için el kuvvetinin bulunmasında üreticilere kolaylık sağlayacaktır.

Sand characteristics such as liquefaction susceptibility can be affected as a result of change in degree of saturation of sand. New liquefaction mitigation technique by inducing partial saturation in sands is introduced by Yegian et al in 2007[1]. This technique requires to monitor changes in degree of saturation of sand. By nature, changes in degree of saturation of sand can lead in changes in its electric conductivity. Electric conductivity is the property of a material that represents its ability to conduct electric current. Fully saturated sand can conduct electric current better than sand with lower degree of saturation. Therefore, the change in measured electric conductivity can be used to calculate the change in degree of saturation of sand. In 1942, Gus Archie [2] expressed that the electric conductivity of soil is a function of its porosity, degree of saturation, tortuosity and electric conductivity of pore fluid. Using Archie’s law electrical conductivity can be related to the degree of saturation in sands. Typically, electric conductivity probes and meters are instruments which are used to measure electric conductivity. Using electrical conductivity probes, sets of bench top tests were conducted on Ottawa sand to study the relation between degree of saturation and electric conductivity in sand. Partial saturation in sands were created by pouring dry sand into sodium percarbonate solution with a known initial concentration. By nature, sodium percarbonate in water, generates oxygen gas bubbles in time. The changes in electric conductivity in the specimen were measured using electric conductivity meters and probes. In addition, changes in degree of saturation of the specimen were measured using soil phase relations equations. Measured electric conductivity data and calculated degree of saturations were correlated to explore relation between electric conductivity and degree of saturation. This paper presents results of bench top tests, and suggests a relationship between, final degree of saturation of sand and initial concentration of sodium percarbonate solution