Ozalp Vayvay - Academia.edu (original) (raw)

Papers by Ozalp Vayvay

Industrial Marketing Management, 2005

Purchasing and supplier involvement as one possible explanatory factor of product development suc... more Purchasing and supplier involvement as one possible explanatory factor of product development success has been gathering growing attention from both managers and researchers. This paper presents the results of a Dutch benchmark study into supplier involvement in product development, and discusses the topic more specifically in the context of the food industry. Regarding supplier involvement, this industry has not been studied intensively, although its specific characteristics make continuous development of new products imperative and the amount of outsourcing of production and development has increased substantially. The benchmark was conducted by means of an existing framework which has not yet been applied to the food industry. The food company in the benchmark study performs consistently better than companies from other industries. At the same time, the results of a similar case study carried out at a Scandinavian food company show contradictory results. By comparing the Dutch and the Scandinavian case, we illustrate that our analytical framework can explain these different results in terms of the underlying processes and preconditions , thereby validating its application to the food industry.

Journal of Naval Science and Engineering, 2009

Tedarik zinciri ağlarında safhalar arasındaki talep bilgisi değişkenliği ve bu değişkenlikteki ar... more Tedarik zinciri ağlarında safhalar arasındaki talep bilgisi değişkenliği ve bu değişkenlikteki artış (Kırbaç Etkisi) zincirin toplam performansına etki eden birkaç sistem kusurunu tetikler. Bu makalede göreli orta değişken talep bilgisi altında, tedarik zinciri ağlarındaki talep değişkenliğinin önerilen bulanık zaman serileri tahmin modeli ve ANFIS tabanlı karar sürecinden oluşan melez sisteme verdiği tepki, bir benzetim modeli ile analiz edilmiştir.

Increased competition and globalization compels most organizations to become innovative and adopt... more Increased competition and globalization compels most organizations to become innovative and adopt change approaches. Business Process Reengineering is one of the most popular change management approaches that can bring incredible solutions to corporations. BPR has arisen as a solution for companies to improve their performances; elevate their efficiencies and gain a competitive advantage in this everlastingly developing and changing world. Even though there have been successful and unsuccessful cases stated in the literature, BPR has been touted as a vital management tool in order to achieve dramatic improvements and organizational competitiveness, if it is implemented properly and carefully. In this context; with this study, we analyze Business Process Reengineering as today’s prominent management trend for organizational change, examine an reengineering project that has been undertaken in a multinational electronics and electrical equipment company, make suggestions for the areas ...

Technological Developments in Industry 4.0 for Business Applications

In every industrial era, one of the most important issues is the adaptation of business condition... more In every industrial era, one of the most important issues is the adaptation of business conditions to operational and administrative processes. Nowadays, as in every field of business-life, globalization and high competition highlighted the importance of entrepreneurship and innovation. The focal point of competition has changed to the position to innovate products at desired and required amounts, times, and quality with affordable price so taking advantage requires integrated management skills. Universities play a key role at this point thus entrepreneurs and researcher universities has emerged. In this study, after a general overview on evaluation of innovation and entrepreneurship concepts, the importance of them are explained in the view of industry 4.0. Then, a model of entrepreneurial and researcher universities is explained in detail with the analysis of several countries' models. The study reveals the role of universities in the innovation and entrepreneurship framework ...

2018 International Conference on Intelligent Systems (IS)

Companies need New Product Development (NPD) more than ever to satisfy rapidly changing customer ... more Companies need New Product Development (NPD) more than ever to satisfy rapidly changing customer needs, to secure and increase their share in the global market. Continuous innovation stream is required to succeed there with best promising ideas to be selected at the fuzzy Front End (FFE). The fuzziness of FE is remedied here by creating an intelligent, self-adaptive and flexible decision model The proposed model is non-bureaucratic, manages fuzziness, and it is capable to provide insight for future trends Furthermore, it contributes to knowledge accumulation by maintaining all data of ideas, both accepted or rejected, enabling knowledge based design. The intelligent is provided by the growth of idea, their computation and assessment. I.e. the model itself weighs ideas independently and adaptively by respecting the size and population of the associated idea group. This is achieved by using K-means clustering algorithm by which meaningful changes in accumulated ideas are detected to calculate trend. The synthesized model supports managers and researchers to organize the FFE.

Nowadays, fierce competition remains a major characteristic of today’s business environment. The ... more Nowadays, fierce competition remains a major characteristic of today’s business environment. The companies have to adopt new technologies in their business processes and especially supply chains to be able to maintain their position and grow. Mobile technologies and their products such as smartphones, tablets, applications etc. are the leading factors which the companies require to follow closely. Dynamic and competitive market drags the companies to the mobile supply chain management (SCM) when redefining their interactions with suppliers, customers and business partners. To understand its benefits, the drivers of mobile supply chain management are explained in detail by giving their use areas in the industry reviewing literature remarkably. In addition, the paper set light to how the firms achieve a sustainable competitive advantage in the marketplace using smartphones and tablets, as well as mobile applications in supply chain management. At the end, new trends and proposals are ...

Supply chain, Whiplash Effect, Forecasting, Fuzzy regression, Fuzzy time series, Neuro-fuzzy, ANF... more Supply chain, Whiplash Effect, Forecasting, Fuzzy regression, Fuzzy time series, Neuro-fuzzy, ANFIS, Exponential Smoothing

Journal of Aeronautics and Space Technologies, 2010

We are in a century of change. The thought of ?the only constant is change? implies this truth. W... more We are in a century of change. The thought of ?the only constant is change? implies this truth. Whatever the circumstances are, both organizations and managers need to keep up with these changes in order to survive and compete better. Increased competition and globalization compels most organizations to become innovative and adopt approaches based on change. In literature, there is an abundance of information available on organizational change. Researchers have written numerous articles, papers and books in this topic and they have several different approaches to how organizations should manage change. Knowing how to adopt and change successfully has become a critical and timeless challenge for any organization. Business Process Reengineering (BPR) is one of these most popular change management approaches which have attracted great attention in this world of change recently. Even though there have been successful and unsuccessful cases stated in the literature, BPR has been touted a...

E3 Journal of Business Management and Economics, 2012

In the information technology industry, projects are often carried out simultaneously and with li... more In the information technology industry, projects are often carried out simultaneously and with limited human resources, being of major relevance to adequately allocate consultants (using either the company’s own consultants or outsourcing) to each project. At the company analyzed, consultants’ allocation to concurrent projects, especially when outsourcing is done, is complex. To solve the decision problem, the Project Resource Planning method (PRP), Analytic Hierarchy Process (AHP), fuzzy AHP and Analytic Network Process (ANP)-based methodologies were used. The experiments suggested that both AHP and fuzzy AHP led to the same results, but neither of these considered the interactions within decision elements during the selection process, while ANP, which takes into account these interactions, most correctly weighs the sub-criteria and gives the best composite weights.

Lojistik hizmet saglayicinin secimi, karar vericinin kalite, maliyet ve dagitim zamani gibi birbi... more Lojistik hizmet saglayicinin secimi, karar vericinin kalite, maliyet ve dagitim zamani gibi birbiri ile celisen bircok amaci eszamanli eniyilemesini gerektiren karmasik cok olcutlu bir karar verme surecidir. Literaturde karar vericilere bu surecte yardimci olmak amaci ile tasarlanan cok cesitli metot ve modeller olmasina ragmen, tasarlanan bu metot ve modelleri kullanarak lojistik servis saglayici secimine sistemsel bir yaklasim getiren calisma cok az bulunmaktadir. Bu calismada bulanik AHP’ye dayali bir lojistik hizmet saglayici secimi karar destek sistemi onerilmistir

Increase in chronic diseases prevalence, longer life expectancy, and improvements in science and ... more Increase in chronic diseases prevalence, longer life expectancy, and improvements in science and engineering speed up the innovations in healthcare technology. In this study it is aimed to provide both a deep understanding in needs of recent health technology assessments and an improvement proposal for health technology assessments studies based on multi criteria decision making (MCDM). It is concluded that an integrated MCDM model is essential for satisfying the current needs of HTA studies.

Build to order market in high technology is growing rapidly. Especially industrial systems in pro... more Build to order market in high technology is growing rapidly. Especially industrial systems in process industry are under narrow time constraints by the investors, despite the high level of complexity. This dualism results in mistakes, rework and loss of profitability. Consequently such product realization companies loose valuable time and in this rush they have difficulties in knowledgeaccumulation and circulation. As a result innovation capability is restricted and the sustainability is jeopardized. In order to isolate key drivers of these problems, a technology oriented international organization was analyzed, where all business processes were captured in a network diagram. Then a process FMEA for the critical path was performed with consequent root cause analysis, indicating potentially the lack of proper IT & requirement management systems with 36.1% as the most critical root cause, followed by the lack of experience with 32.8% and high workload with 31.1%. Subsequently improvem...

Logistics service provider selection is a complex multi – criteria decision making process; in wh... more Logistics service provider selection is a complex multi – criteria decision making process; in which, decision makers have to deals with the optimization of conflicting objectives such as quality, cost, and delivery time. Despite to the great variety of methods and models that have been designed to help decision maker for this process in literature, few efforts have been dedicated to develop systematic approaches for logistics service provider selection using these predesigned methods and models. In this study, logistics service provider selection decision support system based on the fuzzy analytic hierarchy process (FAHP) method is proposed

Promet - Traffic&Transportation

The airline industry has shown significant growth in the last decade according to some indicators... more The airline industry has shown significant growth in the last decade according to some indicators such as annual average growth in global air traffic passenger demand and growth rate in the global air transport fleet. This inevitable progress makes the airline industry challenging and forces airline companies to produce a range of solutions that increase consumer loyalty to the brand. These solutions to reduce the high costs encountered in airline operations, prevent delays in planned departure times, improve service quality, or reduce environmental impacts can be diversified according to the need. Although one can refer to past surveys, it is not sufficient to cover the rich literature of airline scheduling, especially for the last decade. This study aims to fill this gap by reviewing the airline operations related papers published between 2009 and 2019, and focus on the ones especially in the aircraft maintenance routing area which seems a promising branch.

An International Journal of Optimization and Control: Theories & Applications (IJOCTA)

Efficient planning and management of the workforce resources is one of the most essential require... more Efficient planning and management of the workforce resources is one of the most essential requirements for the companies operating in the service sector. For banks, a large number of transactions coming to Central Operations Department from the branches or directly from the customers and their aim is to provide the best operational service with the highest efficiency with the limited workforce resources in the departments. In this study, a real assignment problem was discussed and the problem was considered as Generalized Assignment Problem. For the solution of the problem, related algorithms were listed and examined in the literature survey section. Then, a two-step method is proposed. First step prioritizes the task coming to the system by considering the customer types, service level agreement (SLA) times, cut-off times, task type. In the second step, a multi-objective mathematical model was developed to assign task to employee groups. A preference based optimization method call...

Healthcare

Medical errors negatively affect patients, healthcare professionals, and healthcare establishment... more Medical errors negatively affect patients, healthcare professionals, and healthcare establishments. Therefore, all healthcare service members should be attentive to medical errors. Research has revealed that most medical errors are caused by the system, rather than individuals. In this context, guaranteeing patient safety and preventing medical faults appear to be basic elements of quality in healthcare services. Healthcare institutions can create internal regulations and follow-up plans for patient safety. While this is beneficial for the dissemination of patient safety culture, it poses difficulties in terms of auditing. On the other hand, the lack of a standard patient safety management system, has led to great variation in the quality of the provided service among hospitals. Therefore, this study aims to create an index system to create a standard system for patient safety by classifying medical errors. Due to the complex nature of healthcare and its processes, interval-valued i...

Advances in Logistics, Operations, and Management Science

Sixth International Conference on Advances in Applied Science and Environmental Technology - ASET 2017, Feb 26, 2017

The primary target in this study is to present the tendency of academicians and practitioners tow... more The primary target in this study is to present the tendency of academicians and practitioners towards the reverse logistics (RL) issue. Hence, the literature related to the issue is examined in detail and at the end of the study some valuable information is gathered according to the distribution of artificial intelligence (AI) techniques in various segments of RL. Based on the results presented, it'll be appropriate to decide whether it is a necessity to continue considering the RL concept in managerial processes or not.

Tehnicki vjesnik - Technical Gazette

The total system performance of dynamic and complex supply chain networks depends mainly on accur... more The total system performance of dynamic and complex supply chain networks depends mainly on accurate demand signal estimation as incorporated with an appropriate decision-making process. Due to the field of activity and architecture, however, it is hard to choose a proper forecasting and demand decision model that would befit the complexity of the system. This paper develops a conjoint intelligent hybrid system, comprised of an adaptive neuro-fuzzy inference system (ANFIS) based demand decision process, integrated with crisp grey GM (1,1) and fuzzy grey regression (FGR) forecasting models. We adopt this approach in an attempt to reduce the demand signal variability in supply-chain networks and to evaluate the system response to the proposed models under predefined, relatively low, medium and high demand signal variations. The results obtained from the simulation runs illustrate that the proposed hybrid system reduces the variability considerably; and also, could be considered as a substantial tool for reduction of supply chain phenomenon so called Bullwhip effect.

Sustainability

In an age of rapid technological advancement, the increasing need for energy and its related serv... more In an age of rapid technological advancement, the increasing need for energy and its related services to satisfy economic and social development has become a critical concern of national governments worldwide. This has triggered researchers to work on metrics for tracking and tracing energy sustainability in order to provide monitoring mechanisms for policy makers. In this regard, multicriteria decision-making (MCDM) methods are becoming more popular to deal with the multidimensional and complex nature of sustainability. We have proposed an extended and revised version of the grey relational analysis (GRA) method, which is integrated with the fuzzy analytic hierarchy process (AHP), to develop a new composite index for comparing the overall energy sustainability performances of 35 OECD member countries. Our case study revealed the performances of selected countries by providing their strengths and weaknesses based on determined criteria as well as the level of change in performances ...