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Bu çalışmanın amacı hibrid tip bağlantı uygulanmış termoplastik kompozit plakalardaki ısıl kayma gerilmelerinin belirlenmesidir. Hibrid bağlantı yapıştırıcı ve iki paralel pim uygulaması şeklinde tasarlanmıştır. Problemin çizimi ve çözümü ANSYS yazılımı kullanılarak gerçekleştirilmiştir. Bu yüzden çözümlerde sonlu elemanlar metodu kullanılmıştır. Hibrid bağlantının modellenmesi üç boyutlu olarak yapılmıştır. Tasarlanan yapıdaki ısıl gerilmeler uygulanan uniform sıcaklık yükleri nedeniyle meydana gelmiştir. Elde edilen sonuçlar, ısıl gerilmelerin uniform sıcaklık artışına çok önemli oranda bağlı olduğunu göstermiştir. Kısaca, ısıl kayma gerilmeleri, sıcaklık yükündeki artışa bağlı olarak artmıştır, This paper aims to determine of thermal shear stresses on thermoplastic adherents which are joined by hybrid type. It is designed both adhesive and two parallel pins. Both plotting and solving of this problem were done using ANSYS software. Therefore solutions were performed with finite element methods (FEM). Modeling of hybrid joint was established as three dimensional. Thermal stresses were caused to apply uniform thermal loads on designed structure. Determined results pointed out that thermal shear stresses were strictly affected of increasing uniform thermal loads. Briefly, their values were increased by increasing of thermal loadings.

In this study, a thermal stress analysis was carried out on cross-ply thermoplastic laminated composite plates with square hole. Steel fiber reinforced thermoplastic laminated composite plates with a centered square hole and uniform temperature distribution as thermal loading were selected for the analysis. The orientation angles were chosen symmetric and antisymmetric. The finite element method was used for the analysis. For this purpose, the solution was performed by using ANSYS programme. Uniform temperature loading was chosen between 40 oC and 80 oC. Results, which were obtained from thermal analysis, were illustrated in figures and tables., Bu çalışmada, çapraz takviye edilmiş kare delikli termoplastik levhalarda ısıl gerilme analizi yapılmıştır. Çelik fiberlerle takviye edilmiş, tabakalı ve ortasında kare delik bulunan kompozit levhalara ısıl yük olarak, üniform sıcaklık dağılımı seçilmiştir. Oryantasyon açısı olarak simetrik ve antisimetrik düzenleme yapılmıştır. Analizde, sonlu elemanlar metodu kullanılmıştır. Bu amaçla, çözüm ANSYS programı kullanılarak yapılmıştır. Üniform sıcaklık yükü olarak 40 oC ve 80 oC arasındaki çeşitli sıcaklık değerleri seçilmiştir. Isıl analizlerden elde edilen sonuçlar şekillerde ve tablolarda gösterilmiştir.

The scope of this study is to create a model that predicts failure loads for mechanically fastened composite plates using a fuzzy expert system. The composite material used in the study was manufactured in both a fibre reinforced manner and with glass fibres. The results of a previous experimental study for cross-ply laminated composite plates that were mechanically fastened with two serial pins or bolts were used to model and predict of failure loads. Furthermore, experimental data of a preceding study were obtained with different geometrical parameters for various applied preload moments (pinned/bolted) as 2, 3, 4 and 5 Nm. In this study, a fuzzy expert system and regression analysis methods were applied by using these geometrical parameters and pinned/bolted joint configurations. Therefore, 5 geometrical parameters and 300 test data were used. According to obtained results, it was determined that the fuzzy expert system was more appropriate than the regression analysis method for modelling and prediction. Performances of the fuzzy expert system and regression analysis method were discussed in terms of error ratios and mean absolute deviations. Cilj predstavljene študije je ustvarjanje modela za napovedovanje obremenitve, pri kateri pride do odpovedi mehansko povezanih kompozitnih plošč, z mehkim ekspertnim sistemom. Mehki ekspertni sistemi omogočajo odločanje na podlagi numeričnih operacij namesto na podlagi simboličnih pravil, v čemer se razlikujejo od tradicionalnih ekspertnih sistemov. Mehki podatki omogočajo fleksibilnejšo predstavitev in občutljivejše rezultate. V študiji so bili uporabljeni kompozitni materiali, ojačeni s steklenimi vlakni. Za modeliranje in napovedovanje obremenitev, pri katerih pride do odpovedi, so bili uporabljeni rezultati predhodne eksperimentalne študije kompozitnih plošč z navzkrižno laminiranim plastmi, ki so bile spojene z dvema zatičema ali vijakoma v vrsti Eksperimentalni podatki predhodne študije so bili pridobljeni za različne geometrijske parametre pri različnih predobremenitvenih momentih (zatičnega/vijačnega spoja) 2, 3, 4 oz. 5 Nm. Pravokotni preizkušanci so bili pripravljeni iz laminiranega kompozita epoksi smole in steklenih vlaken, in sicer z dvema krožnima luknjama v vrsti. Pri eksperimentih sta bila uporabljena dva toga zatiča/vijaka.

The recruitment of Turkish migrant workers in Germany was originally a temporary measure because of a shortage of manpower, but over time they settled permanently and were joined by their families. This led to changes in lifestyle and many problems of adaptation. This paper examines the complex integration process, their contribution the Germany economy and the changes that the host society has had to make to fulfil the needs of a community now resident in Germany for 40 years.

WOS: 000348636200001, In this study thermal residual stresses were calculated for a composite disc with many holes using 3D-FEM. Most of previous studies related to thermal stresses and residual stresses of composite disc were performed as two dimensional, but present study was done using three dimensional modelling and FEM, firstly. The composite disc was thermoplastic matrix and steel fibres for reinforcement material as unidirectional for radial direction. Different uniform temperature distributions were subjected to the thermoplastic composite disc as thermal loads. Finite element method (FEM) was used to compute thermal residual stresses. For this purpose, the thermal stress analysis was carried out in two stages as elastic and elastic-plastic solutions. All modelling and solution processes were done using ANSYS finite element software which is known as a general purpose engineering simulation. According to obtained results, thermal residual stresses in thermoplastic composite disc were created by applied thermal loadings owing to the composite disc having different thermal expansions in radial and tangential directions.

In this work, an elastic-plastic thermal and residual stress analysis were performed for adhesively bonded single lap joint. For this purpose, thermoplastic composite adherents were bonded to each other with epoxy adhesive. Thermoplastic composite material was reinforced by steel-fibres, unidirectionally. Finite element method (FEM) was preferred to obtain thermal elastic and elastic-plastic stress distributions on single lap joint. Accordingly, modelling and solution processes were achieved using ANSYS software. So as to determine effects of uniform temperature loadings on thermal and residual stresses, different values of it were loaded on the joint, uniformly. Briefly, both thermal and residual thermal stresses were calculated under uniform temperature loading which was selected from 40 °C to 80 °C. According to obtained results different thermal expansion coefficients of composite adherents and adhesive layer caused thermal and residual stresses on adhesively bonded single lap joint due to applied uniform temperature loadings. Thermal stress values for x and y-directions are very different from each other owing to orthotropic material properties of thermoplastic composite. The magnitudes of elastic analyses results are higher than elastic-plastic analysis results. Contrary to elastic analysis results, elastic-plastic analysis results were nonlinear. Thermal and residual stresses are increased by increasing uniform temperature values, so the highest values were calculated when 80 °C. The plastic yielding was firstly come into being for 50 °C loading and it is expanded related to raising thermal loadings as nonlinear.

Europe is facing a confronlalion prcscntly. On onc hand, theprotection of human rights has gained vveight in public discussion andpolitical negotiation. On the other hand, aggrcssivc nationalism, racism andxenophobia are gaining ground. Thcrefore, one of the most challengingissues of the future Europe will be, and already is, migration. Increasinlymigration has been linked to the concepts of democracy and human rightswhile efforts are being made to arrive at a European Union, with itsdeficiencies with regard to the rights of migrants. The two arc linked becausehow migrants and foreign populations are incorporatcd into the social andpolitical life of the receiving countries is a majör cxplanatory element of theunderstanding of democracy, pluralism and human rights in Europe.

Bu çalışmada, $[45^\circ /-45^\circ ]_2$ açılı oryantasyona sahip, basit \mesnetli, çelik fiberlerle takviye edilmiş, tabakalı ve \dairesel delikli termoplastik kompozitlerde, Uniform sıcaklik etkisiyle meydana gelen ısıl gerilmeler incelenmiştir. Oryantasyon açısı olarak simetrik ve \antisimetrik düzenleme seçilmiştir. Analizde sonlu elemanlar metodu kullanılmıştır. Bu amaçla, çözüm ; ANSYS programı kullanılarak yapılmıştır. Uniform sıcaklık yükü olarak 40 °C ve 80 °C arasındaki çeşitli değerler seçilmiştir. Isıl analizlerden elde edilen sonuçlar şekillerde gösterilmiştir., In this study, a thermal stress analysis is investigated for a uniform temperature effect simply supported angle-ply of the type $[45^\circ /-45^\circ ]_2$, steel fiber reinforced thermoplastic laminated composite plates with a circular hole. The orientation angles are chosen symmetric and antisymmetric. The finite element method is used for the analysis. For this purpose, the solution is obtained by using ANSYS programme. Uniform heat loadings are selected by temperature between 40 °C and 80 °C. Results, which are calculated from thermal analysis, are shown in figures.

Seit einigen Jahren kann man in turkischen Grosstadten wie Istanbul, Ankara und Izmir eine neue Sorte turkischer Wurst kaufen, die fast 80 Prozent teurer ist als die dort hergestellte.

Seit dem Anwerbeabkommen 1961 ist die Zahl turkischer Arbeitnehmer in der Bundesrepublik kontinuierlich angestiegen, lag nach 10 Jahren (1971) bereits deutlich uber einer halben Million und uberschritt weitere 4 Jahre spater (1975) die Millionengrenze. Wegen des 1973 erlassenen Gesetzes uber den Anwerbestopp, das den Zuzug weiterer Arbeitseinwanderer verhindern sollte, holten viele turkische Arbeitsmigranten ihre Familien nach Deutschland, da sie befurchteten, das dies spater nicht mehr moglich sein wurde. Dadurch anderte sich die Sozialstruktur der Einwanderer, die bis dahin eine nahezu reine Erwerbsbevolkerung war. Die turkische Wohnbevolkerung stieg bis auf etwas uber zwei Millionen Ende 1995 an. Heute steht auser Frage, das es sich dabei nicht mehr um eine befristete Arbeitsmigration handelt. Wenn auch weiter viele der heute in Deutschland lebenden Turken wunschen, wenigstens nach dem Ausscheiden aus dem Erwerbsleben in die Turkei zuruckzukehren, so bleibt doch ein deutlich zunehmender Teil auch nach dem Erreichen des Rentenalters in Deutschland.