Ticari Bilimler Fakültesi / Faculty of Commercial Science

Permanent URI for this collectionhttps://hdl.handle.net/11727/2074

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Adventurous and Charismatic Spirits: Entrepreneurs of Veblen and Schumpeter
(2018) Aydin, Derya Guler; Araz, Bahar; Ozer-Imer, Itir; AAC-8845-2021
The aim of this study is to analyze the evolving role of the entrepreneur in the economic and institutional structure based on the analyses of Veblen and Schumpeter. In both analyses, the historical evolution of the entrepreneur is crucial in understanding economic and institutional change. It can be claimed that clues for socio-economic transformation should be searched within institutions, entrepreneurs and habits and by this way, it is possible to demonstrate the mutual interactions between economic and Social spheres. (C) 2018 Elsevier B.V. All rights reserved.
Analysis of Personal Information Security Behavior and Awareness
(2016) Ogutcu, Gizem; Tastik, Ozlem Muge; Chouseinoglou, Oumout; AAD-2902-2020
Hardware and software security mechanisms are widely used to strengthen information systems (IS) against attacks. However, these systems are still highly vulnerable to threats from users' undesirable behaviors, which are closely related to IS users' information security awareness. This study has been carried out in an effort to investigate the IS users' risky behaviors that may threaten information security. The preventive actions employed by users, the threats they may be exposed to, or whether they had an adverse experience or to what extent they perceive risks have also been investigated. Four scales: Risky Behavior Scale (RBS), Conservative Behavior Scale (CBS), Exposure to Offence Scale (EOS) and Risk Perception Scale (RPS), were developed depending on the data collected with the use of surveys. The scales developed from the content of the survey were applied to students, academics and administrative staff of a university, which also embodies hospitals and educational organizations located in different geographical and socio-economical regions of Turkey. On the base of developed scales, the results of the study show that there are significant differences within samples and according to the habits of Internet usage. (C) 2015 Elsevier Ltd. All rights reserved.
An Analysis of The Carrying Capacity And Life Process Risks of UK and Turkish Insurance Intermediaries
(2018) Kirkbesoglu, Erdem; Hood, John; https://orcid.org/0000-0002-6781-9753; ABI-3973-2020
The primary aim of this paper is to examine the strategic risks associated with environmental selection and how this affects the life process risks of insurance intermediaries. To achieve this aim; firstly the carrying capacity of UK and Turkish insurance intermediaries is calculated and, secondly, the demographic, ecological and environmental variables that affect that carrying capacity are examined. Our study provides two contributions to the literature. For the first time, carrying capacity analysis is applied for an organisational community. As much as previous studies assume the existence of carrying capacity as theoretical, it has not been previously calculated on a quantitative basis. The second contribution is related to risk and insurance literature, specifically the life process risks of insurance intermediaries. The main rationale behind that analysis is the construction of a map that will simplify the strategic risk and reward decisions of insurers as to which areas are potentially profitable, or are indicative of fruitful relationships with intermediaries. Additionally, this research enables us to identify the areas that have potential for development in terms of insurance. For this reason, uncertainties relating to the selection of authorised brokers/agents as a strategic risk is, perhaps, minimised. Moreover, we have examined whether probable variables that can affect carrying capacity have contextual differences or not. The findings exhibit that there is contextual differentiations concerning the variables that affect the carrying capacity of both countries.
Angiotensin receptor neprilysin inhibitor for patients with heart failure and reduced ejection fraction: Real-world experience from Turkey (ARNi-TR)
(2021) Ekici, Berkay; Yaman, Mehmet; Kucuk, Murathan; Dereli, Seckin; Yenercag, Mustafa; Yigit, Zerrin; Bas, Mehmet Memduh; Karavelioglu, Yusuf; Cakmak, Huseyin Altug; Kivrak, Tarik; Ozkan, Hakan; Altin, Cihan; Sabanoglu, Cengiz; Demirkan, Burcu; Atas, Ali Ekber; Kilicaslan, Fethi; Altay, Hakan; Tengiz, Istemihan; Erkan, Aycan Fahri; Kilicaslan, Baris; Olgun, Fatih Erkam; Durakoglugil, Murtaza Emre; Alhan, Aslihan; Zoghi, Mehdi; 34308869
Objective: Heart failure (HF) is a growing public health problem with high morbidity and mortality. Recently, angiotensin receptor neprilysin inhibitor (ARNi) has emerged as a promising treatment for HF with reduced ejection fraction (HFrEF). Here, we shared our experience with the use of ARNi in HFrEF from multiple centers in Turkey. Methods: The ARNi-TR is a multicenter, nonintervention al, retrospective, observational study. Overall, 779 patients with HF from 22 centers in Turkey who were prescribed sacubitril/valsartan were examined. Initial clinical status, biochemical and echocardiographic parameters, and New York Heart Association functional class (NYHA-FC) values were compared with follow-up values after 1 year of ARNi use. In addition, the effect of ARNi on number of annual hospitalizations was investigated, and the patients were divided into 2 groups, depending on whether ARNi was initiated at hospitalization or under outpatient clinic control. Results: N-terminal pro-brain natriuretic peptide (NT-proBNP), left-ventricle ejection fraction (LV-EF), and NYHA-FC values improved significantly in both groups (all parameters, p<0.001) within 1-year follow-up. In both groups, a decrease in hemoglobin A1c (HbA1c) values was observed in ARNi use (p<0.001), and a decrease in daily diuretic doses and hospitalizations owing to HF were observed after ARNi use (all comparisons, p<0.001). Hypotension (16.9%) was the most common side effect in patients using ARNi. Conclusion: The ARNi-TR study offers comprehensive real-life data for patients using ARNi in Turkey. The use of ARNi has shown significant improvements in FC, NT-proBNP, HbA1c levels, and LV-EF. Likewise, reductions in the number of annual hospitalizations and daily furosemide doses for HF were seen in this study.
Antecedents of tourist food consumption: food choice motives of foreign tourists in Turkey
(2023) Ekizler, Huseyin; Oksuz, Merve; Durmus, Beril; Shipman, Zehra Dilistan; 0000-0003-2470-7919
Culinary or gastronomy tourism has become a rising issue nowadays. People want to discover new flavour while travelling. Food consumption is the combination of one's cultural, social, psychological and sensory acceptance factors and it is a very complex decision-making process. Food consumption is also associated with motivational factors which are mood, health, sensory appeal, familiarity, convenience, price and natural content. The antecedents of tourist food consumption and food choice motives of foreign tourists in Istanbul were examined. The results show that sensory appeal, mood, natural content, health content and convenience had positive and direct connection with tourist food consumption intentions. There is no statistically significant evidence to support the associations of familiarity and price with the tourist food consumption intentions.
Arf numerical semigroups
(2017) Karakas, Halil Ibrahim; Ilhan, Sedat; AAY-4394-2021
The aim of this work is to exhibit the relationship between the Arf closure of a numerical semigroup S and its Lipman semigroup L(S). This relationship is then used to give direct proofs of some characterizations of Arf numerical semigroups through their Lipman sequences of semigroups. We also give an algorithmic construction of the Arf closure of a numerical semigroup via its Lipman sequence of semigroups.
Arf numerical semigroups with multiplicity 11 and 13
(2022) Karakas, Halil Ibrahim; Ilhan, Sedat; Suer, Meral; AAY-4394-2021
Bibliometric Profiles of Studies on Organization Theory in Turkey: Periodic Comparison of Cite Networks
(2015) Kirkbesoglu, Erdem; Sozen, H. Cenk; Kurt, Esra; 0000-0002-6781-9753; ABI-3973-2020
The purpose of this study is to determine relational links via documents and to have an impression about the development of organization theory in Turkey by using bibliometric methods. Studies of various researchers have been considered with a longditutional approach.The papers which had been presented in National Management and Organization Congress within 10 years were examined in terms of most cited theories, authors, research topics and academic journals. The data were also used for social network analyses to examine interactions between universities, research topics and authors.The data were examined under two periods consist of five years. Findings show that there is a variation between two periods and work style have been transferred to newly founded universities or PhD programs in these universities.
Comparision of PFN and INTERTAN nail for unstable intertrochanteric femoral fracture in mobile patients
(2019) Kochai, Alauddin; Uysal, Mustafa; Ozalay, Metin; Cinar, Bekir Murat; Battal, Vahid; Avci, Mustafa Cagri
Objectives: The ideal implant for the treatment of an unstable intertrochanteric femoral fracture is still a matter of discussion. Intramedullary nails with different varieties of design offer good options in treatment. The aim of this study was to compare two intramedullary nails in different design and reveal the differences by evaluating radiological parameters of patients with unstable intertrochanteric femoral fracture in mobile patients. Material and Method: PFN and INTERTAN nails in two groups were compared overall in 63 patients. Reduction quality and the differences on varus collapse and neck shortening of femur by measuring radiological parameters on early and late postoperative X-rays were examined. Results: Similar radiological results were found between PFN and INTERTAN nails. Reduction quality of fractures was similar between groups. There was a significant difference only in the varus collapse degrees between groups (p<0,001) but no difference in neck shortening. The results revealed that INTERTAN has better resistance to occur varus collapse and the same prevention for neck shortening. Conclusion: Implant design is the one of major factors that may affect the results. INTERTAN nail made a difference in varus collapse of the neck but not in neck shortening. The results of this study have shown that the nail with two adjacent lag screws provides slightly better fixation properties preventing varus collapse than the nail with two separate lag screws. INTERTAN and PFN are currently good options in the treatment of unstable intertrochanteric femoral fractures and sustain enough stability during healing period in mobile patients.
Concurrent Chemoradiotherapy with Vinorelbine plus Split-Dose Cisplatin may be an Option in Inoperable Stage III Non-Small Cell Lung Cancer: A Single-Center Experience
(2015) Mertsoylu, Huseyin; Kose, Fatih; Sumbul, Ahmet Taner; Sedef, Ali Murat; Dogan, Ozlem; Besen, Ali Ayberk; Parlak, Cem; Findikcioglu, Alper; Muallaoglu, Sadik; Sezer, Ahmet; Sakalli, Hakan; Ozyilkan, Ozgur; 25731741
Background: Concurrent chemoradiotherapy is the current standard treatment for inoperable stage III non-small cell lung cancer (NSCLC). In this study we aimed to investigate the efficacy and toxicity of CCRT with split dose of cisplatin (30 mg/m(2)) and vinorelbine (20 mg/m(2)) in patients with inoperable stage III NSCLC followed in our oncology clinic. Material/Methods: Medical records of 97 patients with inoperable stage III NSCLC treated with concurrent chemoradiotherapy with cisplatin-vinorelbine were retrospectively analyzed. Cisplatin (30 mg/m(2)) and vinorelbine (20 mg/m(2)) were administered on days 1, 8, 22, and 29 during radiotherapy. Two cycles of consolidation chemotherapy were given. All patient data, including pathological, clinical, radiological, biochemical, and hematological data, were assessed retrospectively using our database system. Results: Our study included 97 unresectable stage III NSCLC patients who were treated with CCRT. Median age was 58 years old (range 39-75) and 87 (89.7%) of the patients were men. ECOG performance score was 0-1 in 93 patients (95.9%). Squamous histology, the most common histology, was diagnosed in 46 patients (47.4%). Median follow-up time was 23.8 months. Median progression-free survival (PFS) and median overall survival time (OS) were 10.3 months and 17.8 months, respectively. Objective response rate and clinical benefit rate were 75.3% and 83.5%, respectively. Distant and local relapse rate were 57.1% and 42.9%, respectively. Hematological and non-hematological grade 3-4 toxicities were seen in 13 (13.4%) and 16 (16.5%) patients, respectively. Six (6.1%) patients died due to toxicity. Conclusions: The results of this study suggest that split-dose cisplatin may offer fewer grade III-IV toxicities without sacrificing efficacy and could be an option in patients with inoperable stage III NSCLC during CCRT. Similar to past studies, despite high response rate during CCRT, distant relapse is the major parameter that influences patient survival in long-term in NSCLC.
Content-Based Search on Time-Series Microarray Databases Using Cluster-Based Fingerprints
(2017) Ozkoc, Esma Erguner; Ogul, Hasan; AAG-1506-2021
Background: The rapid growth of gene expression databases has created a need for content-based searches as an alternative to unstructured database queries using keyword- or metadata-based searches. Content-based searching is the ability to retrieve all experiments with similar gene expression patterns in a database regardless of the biological annotations provided for these experiments. Objective: While this concept is still in its infancy in a general context, in this study we focus on applying it to a specific subset of gene expression datasets, by only querying experiments involving time-series expression profiles. Method: To this end, we propose a novel experiment fingerprinting scheme obtained by clustering expression profiles, for content-based searching of time-series microarray experiments. To determine the retrieval ability of the proposed scheme, we performed a simulated information retrieval task on a large set of microarray experiments gathered from a public repository. The relevance between any two experiments was then defined using their commonalities based on annotated disease associations. Results and Conclusion: The results showed that relevant experiments can be more successfully retrieved using this new method compared with traditional differential expression-based methods.
Course Selection with AHP & PROMETHEE Methods for Post Graduate Students: An Application in Kirikkale University Graduate School of Natural and Applied Sciences
(2016) Bedir, Neset; Ozder, Emir Huseyin; Eren, Tamer; 0000-0002-1895-8060; AAU-1584-2021
Post Graduate Study has a very important role in people's career planning. Besides, it helps for gaining expertising on their fields. Specializing must be in the right area to reach their targets in line with people's interests. The aim of the study is to propose a model for students that determines which courses will be chosen on master course selection and this model gives an application example. In this study, course selection problem is discussed for post graduate students in Industrial Engineering Department of Kirikkale University. All criteria that are effected for selecting a course are identified by the help of survey then, significance levels are determined with using Analytical Hierarchy Process (AHP) which is a Multi-Criteria Decision Making Method. According to the weights which are determined before in AHP results, six classes weighted by PROMETHEE method in Industrial Engineering Department.
Creative Destruction in International Trade: Insights from the Quadruple and Quintuple Innovation Helix Models
(2020) Carayannis, Elias G.; Acikdilli, Gaye; Ziemnowicz, Christopher
Joseph Schumpeter described the concepts of creative destruction, innovation, and entrepreneurship in the economy. These perspectives can offer ideas to the challenges and opportunities in current international trade issues as well as provide insights for policy makers. Since the end of World War II, nations that fostered free and open international trade experienced competitive business environments, high growth economic growth rates, and increasing standards of living. The globalization process conformed the creative destruction theory as innovation and competition between the leading powers to seek new markets and open new sources for exploitation lead to growth and new spheres of power and influence. Numerous shifts in economic development among countries have occurred, but recent adjustments in wealth and power caused by globalization have resulted in difficult adjustments and altered perceptions as well as the rise of populist social movements that promote forms of mercantilism, protectionism, and economic nationalism. This conceptual overview applies the helix models of innovation to explicate the relationships among business enterprises government, as well as entrepreneurship, change, and socio-economic development. The objective is to model the relationships in national structures as they have positive and negative impacts on economic development, competitiveness, and for international trade under the ever-present state of creative destruction. The present study indicates a need for empirical data among the most affected nations.
Debt maturity structure and stock price crash risk: The case of Turkiye
(2022) Canbaloglu, Bilge; Alp, Ozge Sezgin; Gurgun, Gozde; AAG-3428-2021
This study explores the relationship between the debt maturity structure and the stock price crash risk for nonfinancial firms on the Borsa Istanbul from 2009 to 2019. Family ownership is added to the analyses to provide a new perspective on the literature examining the link between stock price crash risk and debt structure. The results show that an increase in long-term debt reduces the risk of a stock price crash, as efficient corporate management practices not only result in favorable debt issuance at a longer term but also reduces information asymmetry that leads to crash risk at firms. Furthermore, the mitigating effect of long-term debt on crash risk is more pronounced at family-controlled firms because active monitoring by family members causes lower agency conflicts in obtaining longer-term debt as well as in maintaining family status, which in turn also diminishes future stock price crashes. Copyright (c) 2022 Borsa Istanbul Anonim S, irketi. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
A decomposition of partitions and numerical sets
(2020) Karakas, Halil Ibrahim; Tutas, Nesrin; C-2807-2016
The aim of this work is to exhibit a decomposition of partitions of natural numbers and numerical sets. In particular, we obtain a decomposition of a sparse numerical set into the so called hook semigroups which turn out to be primitive. Since each Arf semigroup is sparse, we thus obtain a decomposition of any Arf semigroup into primitive numerical semigroups.
Deviant Employee Behavior in the Eyes of Colleagues: The Role of Organizational Support and Self-Efficacy
(2017) Tuzun, Ipek Kalemci; Cetin, Fatih; Basim, H. Nejat; 0000-0001-6979-2040; 0000-0002-2487-9553; 0000-0002-2605-9962; ABB-5350-2020; J-8116-2015
The present study investigates the influences of multifocal organizational support in the context of deviant employee behavior by examining the potential associations with employees' self-efficacy characteristics. The study proposes that perceived multifocal support and self-efficacy have a direct relationship with deviant behavior, and that these two variables interact in their relationship with deviant workplace behavior. Using self- and peer-reported data from 225 academics, hypothesized relationships were investigated using structural equation modeling. The results indicate that two different forms of support (organizational and supervisory) strongly influenced two different forms of deviant behavior (organizational and interpersonal). Whereas perceived organizational support decreases organizationally relevant deviant behavior, supervisory support decreases deviant behavior toward colleagues. The results also showed that high self-efficacy moderates both the negative relationship between organizational support and deviant behavior toward the organization and that between supervisory support and deviant behavior toward colleagues. The study also discusses the implications of these findings for managers, along with recommendations for future research.
THE EFFECT OF CUSTOMER EMPOWERING BEHAVIOURS ON SERVICE PERFORMANCE IN THE HOSPITALITY INDUSTRY
(2021) Oksuz, Merve
Under highly competitive service industry, customers are more selective while making their decisions. Thus, companies' response customers' needs and wants immediately and meet their expectations by creating unique services. Customers' actions may encourage and motivate employees to make decisions about successful service delivery which is called customer empowering behaviors. This article aims to explain antecedents of customer empowering behaviors which have impacts on employee absorption and customer service performance in the service industry. In this study, a multilevel conceptual model is used and suggests that customer empowering behaviors will be efficient on customer service performance through fostering job engagement. Quantitative research method is used by collecting questionnaires from 421 frontline employees who work either at the reception desk or guest relations in hotels with 4 and 5 stars in the South and South Western districts of Turkey. SEM and HLM were used to analyze collected data in research. The results indicate that customer empowering behaviors play a vital role that affects customer service performance through promoting employee absorption, however, customer complexity has not any significant effect on relationships between customer empowering behaviors and employee absorption and customer service performance.
Effect of Polynomial, Radial Basis, and Pearson VII Function Kernels in Support Vector Machine Algorithm for Classification of Crayfish
(2022) Garabaghi, Farid Hassanbaki; Benzer, Recep; Benzer, Semra; Gunal, Aysel Caglan; 0000-0002-5339-0554; A-5050-2014
Freshwater crayfish are one of the most important aquatic organisms that play a pivotal role in the aquatic food chain as well as serving as bioindicators for the aquatic ecosystem health assessment. Hemocytes, the blood cells of crustaceans, can be considered stress and health indicators in crayfish, and are used to evaluate the health response. Therefore, total hemocyte cell numbers (THCs) are useful parameters to show the health of crustaceans and serve as stress indicators to decide the quality of the habitat. Since, catching the fish and the other aquatic organisms, and collecting the data for further assessments are time-consuming and frustrating, today, scientists tend to use swift, more sophisticated, and more reliable methods for modeling the ecosystem stressors based on bioindicators. One tool which has attracted the attention of science communities in the last decades is machine learning algorithms that are reliable and accurate methods to solve classification and regression problems. In this study, a support vector machine is carried out as a machine learning algorithm to classify healthy and unhealthy crayfish based on physiological characteristics. To solve the non-linearity problem of the data by transporting data to high-dimensional space, different kernel functions including polynomial (PK), Pearson VII function-based universal (PUK), and radial basis function (RBF) kernels are used and their effect on the performance of the SVM model was evaluated. Both PK and PUK functions performed well in classifying the crayfish. RBF, however, had an adverse impact on the performance of the model. PUK kernel exhibited an outstanding performance (Accu-racy = 100%) for the classification of the healthy and unhealthy crayfish.
Effects of Laser Photobiomodulation and Ozone Therapy on Palatal Epithelial Wound Healing and Patient Morbidity
(2018) Isler, Sila Cagri; Uraz, Ahu; Guler, Berceste; Ozdemir, Yucel; Cula, Serpil; Cetiner, Deniz; 0000-0003-2440-6884; 30260741; AAU-7742-2021; AAW-6424-2020
Objective: The aim of this study was to compare the effects of laser photobiomodulation (PBM) and topical ozone therapy on the reepithelialization of palatal donor site wounds through clinical assessment and computer-aided image analysis and to assess the patient morbidity following free gingival graft (FGG) surgeries. Material and methods: Thirty-six patients requiring FGG were randomly allocated into three groups: laser group (n=12), ozone group (n=12), and control group (n=12). Epithelialization was evaluated by applying 3% hydrogen peroxide (H2O2) to the wound area and also measured by using digital image analysis (ImageJ). Bland-Altman plots were used for assessing agreement between H2O2 and ImageJ measurements. Parameters in relation to patient morbidity were assessed by using visual analog scale (VAS) on the first 3, 7, 14, and 30 days postoperatively. Results: At day 14, statistically significant smaller wounds were observed with digital image analysis in the ozone group as compared with the control group (p=0.034). However, intergroup comparison of the remaining wound area evaluated by the clinician using the H2O2 method did not reveal any significant differences (p>0.05). Nonetheless, according to Bland-Altman analysis, the lower and upper limits showed a moderate agreement between the two measurement methods. The mean VAS sores exhibiting postoperative discomfort was observed to be significantly higher in the control group compared with the laser group (p=0.002) and ozone group (p<0.001) at day 7. Conclusions: Adjunctive ozone therapy could have a significantly beneficial effect on the acceleration of palatal wound healing following FGG procedures. Both PBM and ozone treatment modalities reduced postoperative discomfort as compared with spontaneous healing.
The efficiency of primary sovereign bond markets in Turkey: The so-called Fisher puzzle reconsidered
(2022) Sunal, Onur; 0000-0002-3972-4060
Many prior studies have tested the validity of the Fisher effect, with results proving controversial, regardless of the econometric models, country groups, or time spans chosen. Therefore, to solve the so-called Fisher puzzle, this study aims to reveal whether current interest rates, which are set in the primary bond markets, carry information about actual inflation rates when the conventional direction of causation is reversed, using monthly Turkish data from the 2010-2018 period. In line with our expectations, we found a significant long-run coefficient (0.92), which indicates that changes in interest rates are rational expectations of changes in current inflation rates, though a full Fisher effect was not observed. Moreover, the short-run coefficients were also significant, which highlights the fact that the unanticipated movements in these variables act as early signals of persistent future price-level changes. Therefore, monetary authorities should respond rapidly in the short run using rules-based proactive policies to curb long-run volatilities, which also restrict the power of estimations, as market participants tend to assign higher risk premiums to bond yields when prices are expected to surge. (C) 2021 Economic Society of Australia, Queensland. Published by Elsevier B.V. All rights reserved.