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Yayın The economic lot-sizing problem with perishable items and consumption order preference(Elsevier Science BV, 2015-08-01) Önal, Mehmet; Romeijn, H. Edwin; Sapra, Amar; Van den Heuvel, WilcoWe consider the economic lot-sizing problem with perishable items (ELS-PI), where each item has a deterministic expiration date. Although all items in stock are equivalent regardless of procurement or expiration date, we allow for an allocation mechanism that defines an order in which the items are allocated to the consumers. In particular, we consider the following allocation mechanisms: First Expiration, First Out (FEFO), Last Expiration, First Out (LEFO), First In, First Out (FIFO) and Last In, First Out (LIFO). We show that the ELS-PI can be solved in polynomial time under all four allocation mechanisms in case of no procurement capacities. This result still holds in case of time-invariant procurement capacities under the FIFO and LEFO allocation mechanisms, but the problem becomes NP-hard under the FEFO and LIFO allocation mechanisms.Yayın Effects of childhood trauma and clinical features on determining quality of life in patients with bipolar I disorder(Elsevier Science BV, 2014-06-20) Erten, Evrim; Funda Uney, Aslı; Saatçioğlu, İbrahim Ömer; Özdemir, Armağan; Fıstıkçı, Nurhan; Çakmak, DuranBackground: We explored how childhood trauma (CHT) affects the clinical expression of disorder and quality of life in patients with bipolar I (BP I) disorder.Methods: Euthymic patients (n=116) who subsequently received a diagnosis of BP-I disorder were consecutively included and were interviewed using the following sociodemographic and clinical data forms; Young Mania Rating Scale (YMRS), Hamilton Depression Rating Scale (HDRS), Childhood Abuse and Neglect Questionnaire (CANQ) and the 36 item Medical Outcome Study Short Form Health Survey (SF 36) The quality of life of BP-I patients with and without a history of CHT were examined.Results: The percentage of trauma was 61.2%. Patients who had CHT had higher frequencies of depressive episodes (t = -2.38, p=0.019), total episodes (t = -2.25, p=0.026), attempted suicide more often (chi(2)=18.12, p=0.003) and had lower scores on the pain subscale of Lhe SF 36 (z=-2.817, p=0.005). In patients with mixed or rapid-cycling episodes, SF-36 subscale scores except general health and pain were Found to be lower.Limitations: Our sample may fail to reflect the general BD population; the patients were included consecutively and consisted of a majority of female patients.Conclusions: CHT plays an important role in the clinical expression of BP-I disorder and having mixed/rapid-cycling episodes negatively affects both physical and mental components, as measured by the SF-36. While both males and females reported experiencing sexual abuse, female BP-I patients complained about pain more often. It is suggested that treatment of BP-1 patients with a history of CHT should differ from that provided for patients with no CHT history.Yayın Assortment optimization with log-linear demand: application at a Turkish grocery store(Elsevier Ltd, 2019-09) Hekimoğlu, Mustafa; Sevim, İsmail; Aksezer, Sezgin Çağlar; Durmuş, İpekIn retail sector, product variety increases faster than shelf spaces of retail stores where goods are presented to consumers. Hence, assortment planning is an important task for sustained financial success of a retailer in a competitive business environment. In this study, we consider the assortment planning problem of a retailer in Turkey. Using empirical point-of-sale data, a demand model is developed and utilized in the optimization model. Due to nonlinear nature of the model and integrality constraint, we find that it is difficult to obtain a solution even for moderately large product sets. We propose a greedy heuristic approach that generates better results than the mixed integer nonlinear programming in a reasonably shorter period of time for medium and large problem sizes. We also proved that our method has a worst-case time complexity of O(n 2 )while other two well-known heuristics’ complexities are O(n 3 )and O(n 4 ). Also numerical experiments reveal that our method has a better performance than the worst-case as it generates better results in a much shorter run-times compared to other methods.Yayın Pros and cons of using building information modeling in the AEC industry(ASCE-AMER Soc Civil Engineers, 2019-08-01) Seyis Kazazoğlu, SenemAlthough a plethora of studies on building information modeling (BIM) have been conducted in the last decade, none of the previous studies collate and/or prioritize the benefits, risks, and challenges of BIM based on the data collected from a comprehensive literature review and subject matter experts (SMEs). In order to allow architecture, engineering, and construction (AEC) professionals and academics see the true potential of BIM in a wider context and help them understand its multiorganizational and multidisciplinary functions, there is an obvious necessity for identifying, classifying, and prioritizing the pros and cons of BIM; however, such a study is still currently absent in the AEC literature. The aim of this study is to identify, classify, and rank the pros and cons of BIM that address the benefits, challenges, and risks of BIM in the transition from computer-aided design (CAD). A literature review was performed and face-to-face semistructured interviews with SMEs on BIM were conducted for identification and classification purposes. A total of 41 types of benefits, 11 types of risks, and 13 types of challenges of BIM were identified via triangulation of literature review and face-to-face semistructured interviews with SMEs. The Delphi method was performed for prioritizing the benefits of BIM in terms of time, cost, and sustainability as well as the risks and challenges of BIM encountered in the transition process from CAD to BIM. The interrater agreement and significance-level statistics were performed to analyze and validate the consensus reached by the Delphi panel experts. This paper contributes to the existing body of knowledge on BIM by providing comprehensive identification and classification of the benefits, challenges, and risks of BIM, and prioritization of the benefits for BIM in terms of time, cost, and sustainability as well as the risks and challenges of BIM. The priority rankings of benefits, risks, and challenges of BIM ensure successful completion of projects and create additional value by allowing professionals to make well-informed decisions that support decreasing time and cost-related waste in the transition process from CAD to BIM.Yayın A mathematical model for perishable products with price- and displayed-stock-dependent demand(Elsevier Ltd, 2016-12) Önal, Mehmet; Yenipazarlı, Arda; Kundakçıoğlu, Ömer ErhunWe introduce an economic order quantity model that incorporates product assortment, pricing and space-allocation decisions for a group of perishable products. The goal is to maximize the retailer's profit under shelf-space and backroom storage capacity constraints. We assume that the demand rate of a product is a function of the selling prices and the displayed stock levels of all the products in the assortment. We propose a Tabu Search based heuristic method to solve this complex problem.Yayın Sensitivity analysis for models with multiple behavior modes: a method based on behavior pattern measures(2016-12) Hekimoğlu, Mustafa; Barlas, YamanSensitivity analysis of system dynamics models is essentially about sensitivity of patterns of output behaviors to inputs, since system dynamics modeling is behavior pattern oriented. In this study, a regression-based procedure for pattern sensitivity analysis is developed, by defining behavior pattern measures such as equilibrium level, trend, inflection point, or oscillation amplitude. A unique feature of the procedure is that it takes into account the possibility of a model generating multiple behavior modes. This pattern-oriented procedure is next applied to the tipping point project management model and a generic supply line model. These test applications yield sensitivity results that are meaningful, and also consistent with previously available sensitivity information about the parameters of these models. Finally, our pattern sensitivity analysis is shown to be a useful and effective method also for oscillatory system dynamics models, an unsolved sensitivity problem previously in the literature.Yayın I (dis)like the way you (dis)like them: The role of extended contact on social distance and attitudes towards the ingroup(Wiley, 2020-04) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Stathi, Sofia; Vezzali, Loris; Türnüklü, Abbas; Piyale, Zeynep EcemWhile extended intergroup contact has been commonly studied in the context of prejudice reduction, less is known about its implications for processes related to the ingroup. Through three correlational and one experimental studies (total N = 897) conducted in two different intergroup contexts (Turkey and United Kingdom), we investigated whether extended intergroup contact relates to social distance and attitudes towards ingroup members as a function of outgroup attitudes. We also investigated ingroup identification and perceived ingroup morality as potential mediators in these associations. Correlational studies demonstrated that especially when outgroup attitudes were more negative, participants' positive (but not negative) extended contact was related to a more negative evaluation of the ingroup; whereas when outgroup attitudes were more positive, extended contact was associated with positive attitudes towards the ingroup. We found experimental evidence for the suggested relationships in relation to ingroup social distance. Findings are discussed in the light of vicarious dissonance theory and deprovincialization hypothesis.Yayın Location and determinants of productivity: The case of the manufacturing industry in Turkey(M E Sharpe Inc, 2011-11-01) Falcıoğlu, PınarDiscussions in this paper are based on arguments from the geography, economic, and management literatures suggesting that exploring the spatial reasons for productivity in Turkey became significantly important after Turkey became a candidate country. The aim of this paper is to complement the findings of the studies on productivity differences in Turkey's manufacturing industry by exploring the spatial determinants of productivity at the regional level. The discussion is based on an econometric analysis for the years between 1980 and 2000. The results suggest that related variety, proximity to core areas, high wages, and capital intensity contribute to regional productivity.Yayın People respond with different moral emotions to violations in different relational models: a cross-cultural comparison(American Psychological Association, 2021-06) Sunar, Diane; Cesur, Sevim; Piyale, Zeynep Ecem; Tepe, Beyza; Biten, Ali Furkan; Hill, Charles T.; Koç, YasinConsonant with a functional view of moral emotions, we argue that morality is best analyzed within relationships rather than in individuals, and use Fiske's (1992) theory of relational models (RMs: communal sharing [CS], authority ranking [AR]. equality matching [EM], and market pricing [MP]) to predict that violations in different RMs will arouse different intensities of other-blaming emotions (anger, contempt and disgust) in both observers and victims, together with different intensities of self-blaming emotions (shame and guilt) in perpetrators, and to predict that these patterns of emotion will show similarity across both individuals and cultures. Three studies, using vignettes portraying moral violations in all RMs in different experimental designs. supported these expectations. while also producing some unexpected results. The intensity of shame and guilt varied markedly across RMs, but with little difference between the two emotions. The intensity of all 3 other-blaming emotions also varied across RMs. Anger was the most intense emotional response to violation in all RMs, whereas disgust and contempt were stronger in CS than in other RMs. Disgust and shame were linked more strongly in CS than in other RMs, and anger and guilt were more strongly linked than other emotion pairs in EM. Moral emotions in RMs involving hierarchy (AR and MP) differed widely depending on the perpetrator's dominant or subordinate status. Both Turkish (TR) and English-speaking (EN) samples showed similar patterns of all moral emotions across RMs. Understanding the functions of moral emotions in relationships using relational models can help to clarify multiple aspects of moral psychology.Yayın Local elections and the Turkish voter: Looking for the determinants of party choice(Routledge Journals, 2014-10-02) Kalaycıoğlu, Mahmut ErsinOn 30 March 2014 Turkish voters elected their local (city) councillors. Their party preferences seem to indicate considerable correspondence with the national vote choices. So, do voters' choices in local elections differ from voters' party preferences at the national legislative elections? Based on previous research findings on Turkish voting behaviour, a list of hypotheses was compiled and tested, using binary logistic regression analyses and survey data collected immediately prior to the 2009 and 2014 local elections. The main findings are that the party lists are supported at the ballot boxes on the basis of the voters' party identification, ideological positions, and economic (dis)satisfaction, whether in national or local elections.
