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Necessary conditions for partially observed optimal control of general McKean–Vlasov stochastic differential equations with jumps
Get PDFIn this paper, we establish necessary conditions of optimality for partially observed optimal control problems of Mckean–Vlasov type. The system is described by a controlled stochastic differential equation governed by Poisson random measure and an independent Brownian motion. The coefficients of the McKean–Vlasov system depend on the state of the solution process as well as of its probability law and the control variable. The proof of our result is based on Girsanov's theorem, variational equations and derivatives with respect to probability measure under convexity assumption. At the end of this paper, we apply our stochastic maximum principle to study partially observed linear quadratic control problem of McKean–Vlasov type with jumps and derive the explicit expression of the optimal control
Cost and performance comparison for tier-captive and tier-to-tier SBS/RS warehouse configurations
No full textThis paper compares two shuttle-based storage and retrieval system (SBS/RS) configurations developed on travel policy of shuttles in the systems. Specifically, we compare two system configurations of SBS/RS: SBS/RS with tier-captive shuttles and SBS/RS wiScientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); Slovenian Research Agency: ARRSSlovenian Research Agency - Slovenia [118M180]Management; Operations Research & Management ScienceBusiness & Economics; Operations Research & Management Scienc
Kişilik özelliklerinin çevreye duyarlı satın alma davranışına etkisi: Online giyim alışverişi yapanlar üzerine bir değerlendirme
Get PDFSustainable collection center location selection in emerging economy for electronic waste with fuzzy Best-Worst and fuzzy TOPSIS
Get PDFIn emerging economies, electronic waste is an important problem, because it negatively affects the health of staff and people, and causes pollution. Moreover, the location of the collection center has a crucial role in sustainable supply chains. Therefore, in this study, a framework was proposed to identify the location of sustainable collection centers for e-waste. The criteria set includes 3 main criteria, and 23 sub-criteria, and 7 different location options. The main criteria cover economic, social, and environmental criteria, which are organized as the Triple-Bottom-Line dimensions. Alternatives are Manisa, Menemen, Gaziemir, Kemalpaşa, Torbalı, Çiğli, and Akhisar. Fuzzy Best-Worst Method (BWM) and Fuzzy TOPSIS methods are used to calculate the weights of criteria and rankings of the alternatives, respectively. Transportation cost was found as the most important criterion for sustainable collection center selection, followed by collection cost, storage/holding cost, land cost, greenhouse gas emissions, energy cost, tax, and investment cost, respectively. Among other alternatives, Çiğli was found as the best alternative for sustainable collection center, followed by Gaziemir, and Manisa. Managerial implications were presented based on the findings
MUKEA-TCP: A mutant kill-based local search augmented evolutionary algorithm approach for test case prioritization
No full textThe test case prioritization (TCP) problem is defined as determining an execution order of test cases so that important tests are executed early. Different metrics have been proposed to measure importance of test cases. While coverage and fault-detection based measures have benefits and have been used in a lot of studies, mutation kill-based measures have emerged in TCP recently, since they have benefits addressing issues with other approaches. Moreover, in the TCP problem, finding the optimal solution has a complexity of the factorial of the number of test cases, making meta-heuristic algorithms a highly suitable approach. In this study, we propose an end-to-end pipeline for TCP, Mutation Kill-based Evolutionary Algorithm (MuKEA-TCP), which allows users to have fast and efficient TCP results from existing source code, or directly from the mutant kill report of a system, without the need for any coverage information or real faults. An evolutionary algorithm utilizing Average Percentage Mutant Killed (APMK) as the objective function augmented with a local search procedure enhancing is used in MuKEA-TCP. We performed our case study on five open-source Java projects, in which we compared the APMK values of the final TCP results of some well-known greedy algorithms, and MuKEA-TCP using different initialization methods. Our results have shown that providing additional method as an initial input to the proposed augmented evolutionary algorithm has improved the results and outperformed other methods for our case study. Findings of this study have shown that using an evolutionary algorithm augmented with local search with mutation kill-based APMK as the objective function enhances the commonly used greedy prioritization methods, with a minor execution time trade-off
The financial impacts of information systems security breaches on publicly traded companies: reactions of different sectors
Get PDFPurpose: Today, information systems and technology provides a wide set of tools for companies to increase the efficiency of their businesses. Although technology offers many benefits to businesses, it also brings risks as the information systems security breaches. Security breaches and their financial impact is a constant concern of the researchers and practitioners. This paper explores information systems breaches and their financial impacts on the publicly traded companies in different sectors. Design/methodology/approach: After a comprehensive data collection process, data from 192 events are analyzed by employing Event Study Methodology and a comparison of the results between the four highly affected sectors (Consumer Goods, Technology, Financial and Communications) is presented. The abnormal returns on the prices of stocks after the events are calculated with the Market Model. Also, the results of the Market Adjusted Model and Mean Adjusted Model are presented to support the results. Findings: While information systems security breaches have a significant negative impact on the Financials and the Technology sectors for all the event windows in the study ([−5, 0], [−5, 1], [−5, 5], and [−5, 10]), the significant negative impact is observed only on the [−5, 5] and [−5, 10] event windows for the Consumer Goods sector. No significant negative impact is observed in the Communications sector, in fact, the cumulative abnormal returns are positive for this sector. Originality/value: The contribution of this paper to provide evidence about the financial impacts of the information systems breaches for businesses in different sectors. While there are studies that have previously focused on the information systems breaches and their financial impacts on businesses, to the best of our knowledge, this is the first study that compares this effect between the four highly impacted sectors. With a relatively larger sample size and broader event windows than the past studies in the literature, statistical evidence is provided to managers to justify their investments in information security and build preventive measures to secure the market value of their firms
Analyzing barriers of circular food supply chains and proposing industry 4.0 solutions
No full textThe concept of the circular economy (CE) has gained importance worldwide recently since it offers a wider perspective in terms of promoting sustainable production and consumption with limited resources. However, few studies have investigated the barriers to CE in circular food supply chains. Accordingly, this paper presents a systematic literature review of 136 papers from 2010 to 2020 from WOS and Scopus databases regarding these barriers to understand CE implementation in food supply chains. The barriers are classified under seven categories: “cultural”, “business and business finance”, “regulatory and governmental”, “technological, “managerial”, “supply-chain management”, “knowledge and skills”. The findings show the need to identify barriers preventing the transition to CE. The findings also indicate that these challenges to CE can be overcome through Industry 4.0, which includes a variety of technologies, such as the Internet of Things (IoT), cloud technologies, machine learning, and blockchain. Specifically, machine learning can offer support by making workflows more efficient through the forecasting and analytical capabilities of food supply chains. Blockchain and big data analytics can provide the necessary support to establish legal systems and improve environmental regulations since transparency is a crucial issue for taxation and incentives systems. Thus, CE can be promoted via adequate laws, policies, and innovative technologies
Evaluation of Transition Barriers to Circular Economy: A Case from the Tourism Industry
No full textCurrent economic system exhibits a linear path by using resources to produce goods and disposing of waste after their consumption. Circular economy (CE) turns this linear pattern into a circular one by using waste as a resource for another process. It focuses on environmental responsibility, efficiency, renewable resources, preventing wastage, and, minimizing consumption. CE helps the sustainability of the economy by restructuring the production processes to use fewer resources and extending the lifetime of the products. Although there are powerful drivers for transition to CE firms often face significant barriers while implementing their plans. This study aims to evaluate the barriers that the tourism industry would face during the transition process and put them in order according to their importance. We used the Interval Type-2 Fuzzy Analytical Hierarchy Process (FAHP) method which is based on a pairwise comparison of relevant criteria to calculate the weights of importance of these barriers. We conducted semi-structured interviews with four experts from the tourism industry. According to our results, the most important barrier is organizational structure/infrastructure that creates inconvenience with the supply chain. The results are expected to be a guide for the firms in the tourism industry for their transition to CE applications
Örgütsel iletişimin örgütsel bağlılık üzerine etkisi: Turizm sektöründe otel çalışanlarına yönelik bir araştırma
Get PDFThe Biometric Signature as a Blockchain Application
Get PDFThe Internet would be the largest one had it been a country of the world. The population and the produced and consumed data in this new country have been exponentially increasing, and the metrics with which one can measure all this growth are zettabytes, if not the yottabytes now. The issue of forgery detection on authentication and integrity and on the ownership of the data and the users grows incrementally along with this unprecedented growth of the Internet. With the advancements in hardware and software resulting in the Internet of Things (IoT), the checking against forgery will be even harder to perform since anything and everything will be interconnected as never seen before. Signing a document has always been a direct proof for belonging and authentication of the person. Thus, forgery has always been an equally likely issue to be encountered. While the journey of the signatures in the Internet era will be browsed in this chapter, the biometric signature as a complete and better-suited answer to the problem of forgery will be introduced within ironclad protection provided by a blockchain structure which is a new cybersecurity architecture in the domain of the IoT