Özdemir, Serpil

Özdemir, Serpil

Name Variants

Özdemir, Serpil
S.,Özdemir
S. Özdemir
Serpil, Özdemir
Ozdemir, Serpil
S.,Ozdemir
S. Ozdemir
Serpil, Ozdemir
Ozdemir, Nurten Karacan
Ozdemir, Salih C.
Özdemir, Aydoğan
Özdemir, Zeynep
Ozdemir, Mehmet Akif

Job Title

Öğr. Gör.

Email Address

Serpıl.ozdemır@khas.edu.tr

Full item page

Scholarly Output

16

Articles

5

Citation Count

0

Supervised Theses

1 Scholarly Output Search Results

Now showing 1 - 10 of 15

How Does New Media Affect the Creative Department of Advertising Agencies in Turkey?
(Kadir Has Üniversitesi, 2014) Özdemir, Serpil; Yalkın, Çağrı; Binay Kurultay, Ayşe; Yanardağoğlu, Eylem
Bu çalışmanın amacı, yeni birer reklam mecrası haline dönüşen dijital platformların Türk Reklam Ajanslarının kreatif departmanlarının işleyişine etkilerini araştırmaktır. Reklam sektöründe son yıllarda yaşanan dijital dönüşümün, reklamın en önemli unsuru olan yaratıcılık becerisini nasıl değiştirdiğini, yaratıcı departmanların bu değişimle birlikte nasıl bir dönüşüm yaşadığını incelemektir. Öncelikle reklam tarihinin ve yaratıcılığın tarihsel gelişiminin inceleneceği bu çalışmada yakın zamanda ortaya çıkan geleneksel ajans-dijital ajans ayırımının yaratıcı departmanlarda çalışan reklamcıların iş ve görev tanımlarına nasıl yansıdığnın incelemesi yapılacaktır. Yakın zamanda Türkiye'deki yaratıcı ajansların yapısal değişikliğine dair yapılacak bu çalışma için otuza yakın üst düzey yaratıcı-yöneticilerle derin mülakat yapılması hedeflenmektedir. Farklı ajans türlerinden- Geleneksel ajanslardan, dijital ajanslardan, sosyal medya ajanslarından, entegre ajanslardan seçilmiş yaratıcı reklamcılara üç önemli konu hakkında sorular sorulacaktır: 1. Yeni medya, reklam ajanslarının kreatif departmanlarını yapısal olarak nasıl değiştirdi? Bu deparmanlarda çalışanların iş ve görev tanımlarını değiştirdi mi? Değiştirdiyse nasıl? 2. Yeni medyanın, reklam ajanslarındaki yaratıcı departmanların fonksiyonlarına etkisi ne oldu? Yaratıcı süreci nasıl etkiledi? 3. Yeni medya, yaratıcı ajansların müşterileriyle ilişkilerini hangi yönde etkiledi? Ajanslar arası ilişkileri nasıl yapılandırdı? Bu çalışmanın sonunda hedeflenen, dijital devrimin neden olduğu yeni medyanın ihtiyaçlarına cevap verecek, aynı zamanda geleneksel mecralara etkin yaratıcı çözümler sunan en etkili yaratıcı departmanın tarifini yaparak yakın geleceğin ideal reklam ajanslarıyla ilgili öngörüler geliştirmektir.
Citation Count: 0
A Qualitative Study of Unveiling School Dropout Complexity in Türkiye
(Springer, 2024) Ozdemir, Nurten Karacan; Kemer, Fatma Nur Aras; Arslan, Arif; Tuna, Burak
This study investigates school dropout, particularly the shift to open high schools in Turkiye during the pandemic, through a multi-stakeholder lens. Using grounded theory, data was collected via semi-structured interviews with 12 students, 15 teachers, and 20 school administrators. Results reveal a model linking themes: predictive reasons for transferring to open high school, both pandemic-related and unrelated, positive/negative consequences of the transition, pandemic's impact on formal education continuity, essential open high school skills, and strategies to reduce such preferences. Findings highlight the sway of exam-focused education on open high school interest, regardless of COVID-19, and emphasize the need for equitable education amidst Turkiye's pandemic challenges. Theoretical implications may infer the necessity of approaching school dropout as a multilayered dynamic issue within the cultural context. The implications also may convey the significance of policies and systems not only to reduce the rates of school dropout but also critically unpack underlying reasons to make improvements.
Citation Count: 0
Towards Faster Branch Outage Simulations Using Simulated Annealing and Parallel Programming
(IEEE, 2009) Ceylan, Oğuzhan; Özdemir, Aydoğan; Dağ, Hasan
Contingency studies such as branch outage and generator outage are among important studies of energy management centers operations. Branch outage modeling on the other hand is one of the basic steps of post-outage state estimation of an electrical power system. Real time implementation of the problem brings the necessity of using high speed methods while providing a reasonable accuracy. This paper presents simulated annealing based solution of the branch outage event which is formulated as a local optimization problem. To speed up the solution procedure the distributed computing toolbox of Matlab is used as a parallel programming tool. The results of the proposed method are compared to those of full AC method and are discussed both from the point of accuracy and solution speed.
Citation Count: 2
Double Branch Outage Modeling and Simulation: Bounded Network Approach
(Elsevier Science, 2015) Ceylan, Oğuzhan; Özdemir, Aydoğan; Dağ, Hasan
Energy management system operators perform regular outage simulations in order to ensure secure operation of power systems. AC power flow based outage simulations are not preferred because of insufficient computational speed. Hence several outage models and computational methods providing acceptable accuracy have been developed. On the other hand double branch outages are critical rare events which can result in cascading outages and system collapse. This paper presents a double branch outage model and formulation of the phenomena as a constrained optimization problem. Optimization problem is then solved by using differential evolution method and particle swarm optimization algorithm. The proposed algorithm is applied to IEEE test systems. Computational accuracies of differential evolution based solutions and particle swarm optimization based solutions are discussed for IEEE 30 Bus Test System and IEEE 118 Bus Test System applications. IEEE 14 Bus Test System IEEE 30 Bus Test System IEEE 57 Bus Test System IEEE 118 Bus Test System and IEEE 300 Bus Test System simulation results are compared to AC load flows in terms of computational speed. Finally the performance of the proposed method is analyzed for different outage configurations. (C) 2015 Elsevier Ltd. All rights reserved.
Citation Count: 8
Voltage Profile Improving and Peak Shaving Using Multi-Type Distributed Generators and Battery Energy Storage Systems in Distribution Networks
(Institute of Electrical and Electronics Engineers Inc., 2020) Ahmedi, Bahman; Ceylan, Oğuzhan; Özdemir, Aydoğan
Optimal sizing and siting of distributed generation (DG) units play an important role for improving voltage profile and reducing power losses. Moreover, battery energy storage system (BESS) units may help peak shaving. This paper presents a two stage approach, first of which aims optimal DG unit allocation, and second aims to determine optimal location and operation of BESS units. The problem formulation adopted due to the regulations in Turkey that supports DG units (Photovoltaics-PVs and Wind Turbines-WTs) with maximum unit size of 1 MW. A recently developed heuristic optimization method named as Harris hawks optimization (HHO) algorithm is used for obtaining near optimal solutions. We tested the developed model by using 33 and 141 bus distribution test systems.
Citation Count: 0
Parallel Contingency Analysis Using Differential Evolution Based Solution for Branch Outage Problem
(IEEE, 2010) Ceylan, Oğuzhan; Dağ, Hasan; Özdemir, Aydoğan
Contingency analysis is one of the most fundamental work an electricity management center operator has to perform regularly. If both bus voltage magnitudes and reactive power flowing on the branches during any type of outages are within the acceptable limits the system is called secure. In this paper we solve the contingency problem using a recently developed local constrained optimization based branch outage problem. The optimization problem resulted from the formulation of branch outage is solved by differential evolution method. Using Matlab's parallel computing toolbox contingency analysis for IEEE 300 test system is performed and the results are presented. The study shows that it is straight forward to implement contingency analysis on the Matlab's parallel environment and obtain near linear speedups.
Citation Count: 19
Grey Wolf Optimizer for Allocation and Sizing of Distributed Renewable Generation
(Institute of Electrical and Electronics Engineers Inc., 2019) Ahmadi, Bahman; Ceylan, Oğuzhan; Özdemir, Aydoğan
Increasing penetration of distributed energy resources (DERs) have brought operational and control philosophy changes in Smart Grids (SGs). Renewable energy based technologies are becoming more important due to their economic and environmental impacts. Distributed generations (DGs) in the form of small renewable energy resources such as solar photovoltaics (PVs) and Wind Turbines (WTs) are connected in radial distribution networks near to the loads. This paper presents optimal siting and sizing of distributed renewable energy resource to maintain voltage magnitude profiles. Bus voltage magnitude differences for each hour in a day of a distribution system are formulated as an objective function. Three consecutive days are taken into account representing the three seasons of a year. A new nature inspired algorithm Grey Wolf Optimizer (GWO) is used as a solution tool. The proposed formulation is applied to 33 bus and 69 bus radial distribution networks. MATLAB simulations are performed to validate the performance of the approach. Simulation results are discussed and compared with of the several available ones'.
Citation Count: 11
Optimal Allocation Of Multi-Type Distributed Generators For Minimization Of Power Losses In Distribution Systems
(Institute of Electrical and Electronics Engineers Inc., 2019) Ahmadi, Bahman; Ceylan, Oğuzhan; Özdemir, Aydoğan
Distributed generation (DG), including photovoltaics (PVs), wind turbines (WTs) are becoming vital for Active Distribution Networks (ADN). Therefore, optimal sizing and allocation of these units can improve voltage profiles and reduce active power losses. This study concentrates on optimal allocation and sizing of two kinds of DG units (PVs and WTs) with 1 MW maximum size limits, due to the regulations in Turkey. The Whale optimization algorithm (WOA) and Grey wolf optimization algorithm (GWO) are used as optimization tools to minimize active power losses of 33 and 69 Bus Test Systems. The performance analysis of the methods are performed through simulations and the numerical results are compared in terms of optimal OF values and convergence characteristics.
Citation Count: 7
Antifungal Screening and in Silico Mechanistic Studies of an In-House Azole Library
(2019) Sarı, Suat; Kart, Didem; Sabuncuoğlu, Suna; Doğan, İnci Selin; Özdemir, Zeynep; Bozbey, İrem; Gencel, Melis; Eşsiz, Şebnem; Reynisson, Jóhannes; Karakurt, Arzu; Saraç, Selma; Dalkara, Sevim
Systemic Candida infections pose a serious public health problem with high morbidity and mortality. C. albicans is the major pathogen identified in candidiasis; however, non-albicans Candida spp. with antifungal resistance are now more prevalent. Azoles are first-choice antifungal drugs for candidiasis; however, they are ineffective for certain infections caused by the resistant strains. Azoles block ergosterol synthesis by inhibiting fungal CYP51, which leads to disruption of fungal membrane permeability. In this study, we screened for antifungal activity of an in-house azole library of 65 compounds to identify hit matter followed by a molecular modeling study for their CYP51 inhibition mechanism. Antifungal susceptibility tests against standard Candida spp. including C. albicans revealed derivatives 12 and 13 as highly active. Furthermore, they showed potent antibiofilm activity as well as neglectable cytotoxicity in a mouse fibroblast assay. According to molecular docking studies, 12 and 13 have the necessary binding characteristics for effective inhibition of CYP51. Finally, molecular dynamics simulations of the C. albicans CYP51 (CACYP51) homology model's catalytic site complexed with 13 were stable demonstrating excellent binding.
Citation Count: 0
Impacts of Load and Generation Volatilities on the Voltage Profiles Improved by Distributed Energy Resources
(Institute of Electrical and Electronics Engineers Inc., 2020) Ahmedi, Bahman; Ceylan, Oğuzhan; Özdemir, Aydoğan
Weather-dependent distributed renewable energy sources such as photovoltaics (PVs) and wind turbines (WT) are increasingly being connected to distribution networks (DNs). Increased penetration of these intermittent sources brought the necessity of using energy storage systems (ESSs) to achieve the intended benefits. This study presents an optimization process to determine optimal numbers, sizes, locations and distributed energy resources (DERs) as well as to determine the optimal operating strategy of ESSs in a distribution network. The objective is to improve the voltage profile and to minimize the installation costs. The proposed multi-objective formulation problem is solved by using ant lion multi-objective optimization algorithm. At the second part of the study, optimal values are tested with monthly extreme distributions and the impacts of load and distributed generation volatilies on the voltage profiles which were determined by Pareto-optimal solution candidates are analysed. Simulations were performed on 33 bus radial distribution system using Matlab. Finally the benefits obtained by the optimal solutions with less risk are compared.