Search results for: Levent Acar
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 47

Search results for: Levent Acar

47 Decentralized Control of Interconnected Systems with Non-Linear Unknown Interconnections

Authors: Haci Mehmet Guzey, Levent Acar

Abstract:

In this paper, a novel decentralized controller is developed for linear systems with nonlinear unknown interconnections. A model linear decoupled system is assigned for each system. By using the difference actual and model state dynamics, the problem is formulated as inverse problem. Then, the interconnected dynamics are approximated by using Galerkin’s expansion method for inverse problems. Two different sets of orthogonal basis functions are utilized to approximate the interconnected dynamics. Approximated interconnections are utilized in the controller to cancel the interconnections and decouple the systems. Subsequently, the interconnected systems behave as a collection of decoupled systems.

Keywords: decentralized control, inverse problems, large scale systems, nonlinear interconnections, basis functions, system identification

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46 Some Plant-Based Handmade Tools and Theirs Uses in Kadınhanı, Konya, Turkey and Its Vicinity

Authors: Yavuz Bağcı, Levent Keskin

Abstract:

The study was carried out in 2011-2014 period to determine plant-based hand tools uses of plants in Kadınhanı (Konya) and surrounding villages. A total of 153 individuals, who lived or were living during this study in 4 towns, 37 villages and 9 neighborhood were interviewed. It was found that of a total about 20 plants belonging to 10 families in the study area, about 60 hand-made goods were used by peoples for various purposes.

Keywords: ethnobotanic, handmade, Kadınhanı, Konya, plant-human relationship

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45 Two Degree of Freedom Spherical Mechanism Design for Exact Sun Tracking

Authors: Osman Acar

Abstract:

Sun tracking systems are the systems following the sun ray by a right angle or by predetermined certain angle. In this study, we used theoretical trajectory of sun for latitude of central Anatolia in Turkey. A two degree of freedom spherical mechanism was designed to have a large workspace able to follow the sun's theoretical motion by the right angle during the whole year. An inverse kinematic analysis was generated to find the positions of mechanism links for the predicted trajectory. Force and torque analysis were shown for the first day of the year.

Keywords: sun tracking, theoretical sun trajectory, spherical mechanism, inverse kinematic analysis

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44 Heat Transfer Enhancement via Using Al2O3/Water Nanofluid in Car Radiator

Authors: S. Movafagh, Y. Bakhshan

Abstract:

In this study, effect of adding Al2O3 nanoparticle to base fluid (water) in car radiator is investigated numerically. Radiators are compact heat exchangers optimized and evaluated by considering different working conditions. The cooling system of a car plays an important role in vehicle's performance, consists of two main parts, known as radiator and fan. Improving thermal efficiency of engine leads to increase the engine's performance, decline the fuel consumption and decrease the pollution emissions. In this study, the effects of fluid inlet flow rate and nanoparticle volume fraction on heat transfer and pressure drop of acar radiator are studied.

Keywords: forced convection, nanofluid, radiator, CFD simulation

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43 Performance Comparison of a Low Cost Air Quality Sensor with a Commercial Electronic Nose

Authors: Ünal Kızıl, Levent Genç, Sefa Aksu, Ahmet Tapınç

Abstract:

The Figaro AM-1 sensor module which employs TGS 2600 model gas sensor in air quality assessment was used. The system was coupled with a microprocessor that enables sensor module to create warning message via telephone. This low cot sensor system’s performance was compared with a Diagnose II commercial electronic nose system. Both air quality sensor and electronic nose system employ metal oxide chemical gas sensors. In the study experimental setup, data acquisition methods for electronic nose system, and performance of the low cost air quality system were evaluated and explained.

Keywords: air quality, electronic nose, environmental quality, gas sensor

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42 Healing Architecture and Evidence Based Design: An Interior Design Example in Medicana KızıLtoprak Hospital

Authors: Yunus Emre Kara, Atilla Kuzu, Levent Cirpici

Abstract:

Recently, in the interior design of hospitals, the effect of the physical environment on the healing process has been frequently emphasized, and the importance of psychological and behavioral factors has increased day by day. When designing new hospital interiors, it became important to create spaces that not only meet medical requirements but also support the healing process of patients with interior design. In this study, the patient rooms, corridor, atrium area, waiting area, and entrance counter in a hospital were handled with patient-centered design, evidence-based design, and remedial architectural approaches, and it was seen that the healing and reassuring elements in hospitals were extremely important.

Keywords: evidence based design, healing architecture, hospital, organic design, parametric design

Procedia PDF Downloads 151
41 Points of View on Turkish Trade Marks by Foreigners Living in Konya

Authors: İmran Ugur, Zulfiye Acar

Abstract:

Trade marks are composed of figures, signs or symbols such as logos, colours and designs to be formed for service or products to be different from their counterparts. However, trade marks have nowadays a large meaning that defines its classical description. It has an understanding that pioneers novelties by forming the perception of quality, being emotional constituents and leading to links to their consumers. While entering different markets all over the world, Turkish trade marks are encountering a new type of consumers in Turkey migrating from different countries. Most of these new consumers meet Turkish trade marks for the first time. The present study was performed to investigate the perception of Turkish trade marks living in Konya. How these consumers look at the trade marks of clothes, food, beverages, GSM operators and whiteware appliances, and perceive these trade marks were tried to be determined. Which trade marks they chose according to their preferences, and the awareness of Turkish trade marks were evaluated in the study.

Keywords: brand, brand awareness, culture, trade marks

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40 Corrosion Protection of Steel 316 by Electrochemically Synthesized Conductive Poly (O-Toluidine)

Authors: H. Acar, M. Karakışla, L. Aksu, M. Saçak

Abstract:

The corrosion protection effect of poly(o-toluidine) (POT) coated on steel 316 electrode was determined in corrosive media such as NaCl, H2SO4 and HCl with the use of Tafel curves and electrochemical impedance spectroscopy techniques. The POT coatings were prepared with cyclic voltammetry technique in aqueous solution of oxalic acid and they were characterized by FTIR and UV-Visible absorption spectroscopy. The Tafel curves revealed that the POT coating provides the most effective protection compared to the bare steel 316 electrode in NaCl as corrosive medium. The results were evaluated based upon data decrease of corrosion current and shift to positive potentials with the increase of number of scans. Electrochemical impedance spectroscopy measurements were found to support Tafel data of POT coating.

Keywords: corrosion, impedance spectroscopy, steel 316, poly(o-toluidine)

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39 Evaluation of Water Quality for the Kurtbogazi Dam Outlet and the Streams Feeding the Dam (Ankara, Turkey)

Authors: Gulsen Tozsin, Fatma Bakir, Cemil Acar, Ercument Koc

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Kurtbogazi Dam has gained special meaning for Ankara, Turkey for the last decade due to the rapid depletion of nearby resources of drinking water. In this study, the results of the analyses of Kurtbogazi Dam outlet water and the rivers flowing into the Kurtbogazi Dam were discussed for the period of last five years between 2008 and 2012. The quality of these surface water resources were evaluated in terms of pH, temperature, biochemical oxygen demand (BOD5), nitrate, phosphate and chlorine. They were classified according to the Council Directive (75/440/EEC). Moreover, the properties of these surface waters were assessed to determine the quality of water for drinking and irrigation purposes using Piper, US Salinity Laboratory and Wilcox diagrams. The results revealed that the quality of all the investigated water sources are generally at satisfactory level as surface water except for Pazar Stream in terms of ortho-phosphate and BOD5 concentration for 2008.

Keywords: Kurtbogazi dam, water quality assessment, Ankara water, water supply

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38 Evaluation of Manual and Automatic Calibration Methods for Digital Tachographs

Authors: Sarp Erturk, Levent Eyigel, Cihat Celik, Muhammet Sahinoglu, Serdar Ay, Yasin Kaya, Hasan Kaya

Abstract:

This paper presents a quantitative analysis on the need for automotive calibration methods for digital tachographs. Digital tachographs are mandatory for vehicles used in people and goods transport and they are an important aspect for road safety and inspection. Digital tachographs need to be calibrated for workshops in order for the digital tachograph to display and record speed and odometer values correctly. Calibration of digital tachographs can be performed either manual or automatic. It is shown in this paper that manual calibration of digital tachographs is prone to errors and there can be differences between manual and automatic calibration parameters. Therefore automatic calibration methods are imperative for digital tachograph calibration. The presented experimental results and error analysis clearly support the claims of the paper by evaluating and statistically comparing manual and automatic calibration methods.

Keywords: digital tachograph, road safety, tachograph calibration, tachograph workshops

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37 Bringing Ethics to a Violent System

Authors: Zeynep Selin Acar

Abstract:

In international system, there has always been a cycle of violence, war and peace. As there travels the time, after Christianity and later Just War theorists, international relations theorists have been tried to limit violence and war. As pieces of international law, Peace of Augsburg, Kellog-Briand Pact, League of Nations Covenant and UN Charter were and are still not effective to prevent war. Moreover, in order to find a way around these rules, it is believed that a new excuse started to be used instead of violence or war, humanitarian intervention. However, it has neither a legal nor a universally accepted framework. As a result, it is open to be manipulated by states. In order to prevent this, Responsibility to Protect (RtoP) which gives a state the responsibility to protect its citizens against violence, is created. Additionally, RtoP transfers this responsibility to regional or international group of states at the time when a state is the origin of violence. In the lights of these, this paper analyzes RtoP as an ethical approach to war and peace studies because it provides other states as guardians and care-takers of people who do not belong to them or do not share any togetherness.

Keywords: ethics, humanitarian intervention, responsibility to protect, UN charter

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36 Smart Irrigation System

Authors: Levent Seyfi, Ertan Akman, Tuğrul C. Topak

Abstract:

In this study, irrigation automation with electronic sensors and its control with smartphones were aimed. In this context, temperature and soil humidity measurements of the area irrigated were obtained by temperature and humidity sensors. A micro controller (Arduino) was utilized for accessing values of these parameters and controlling the proposed irrigation system. The irrigation system could automatically be worked according to obtained measurement values. Besides, a GSM module used together with Arduino provided that the irrigation system was in connection to smartphones. Thus, the irrigation system can be remotely controlled. Not only can we observe whether the irrigation system is working or not via developed special android application but also we can see temperature and humidity measurement values. In addition to this, if desired, the irrigation system can be remotely and manually started or stopped regardless of measured sensor vales thanks to the developed android application. In addition to smartphones, the irrigation system can be alternatively controlled via the designed website (www.sulamadenetim.com).

Keywords: smartphone, Android Operating System, sensors, irrigation System, arduino

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35 The Use of Thermal Infrared Wavelengths to Determine the Volcanic Soils

Authors: Levent Basayigit, Mert Dedeoglu, Fadime Ozogul

Abstract:

In this study, an application was carried out to determine the Volcanic Soils by using remote sensing.  The study area was located on the Golcuk formation in Isparta-Turkey. The thermal bands of Landsat 7 image were used for processing. The implementation of the climate model that was based on the water index was used in ERDAS Imagine software together with pixel based image classification. Soil Moisture Index (SMI) was modeled by using the surface temperature (Ts) which was obtained from thermal bands and vegetation index (NDVI) derived from Landsat 7. Surface moisture values were grouped and classified by using scoring system. Thematic layers were compared together with the field studies. Consequently, different moisture levels for volcanic soils were indicator for determination and separation. Those thermal wavelengths are preferable bands for separation of volcanic soils using moisture and temperature models.

Keywords: Landsat 7, soil moisture index, temperature models, volcanic soils

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34 Machinability Study of A201-T7 Alloy

Authors: Onan Kilicaslan, Anil Kabaklarli, Levent Subasi, Erdem Bektas, Rifat Yilmaz

Abstract:

The Aluminum-Copper casting alloys are well known for their high mechanical strength, especially when compared to more commonly used Aluminum-Silicon alloys. A201 is one of the best in terms of strength vs. weight ratio among other aluminum alloys, which makes it suitable for premium quality casting applications in aerospace and automotive industries. It is reported that A201 has low castability, but it is easy to machine. However, there is a need to specifically determine the process window for feasible machining. This research investigates the machinability of A201 alloy after T7 heat treatment in terms of chip/burr formation, surface roughness, hardness, and microstructure. The samples are cast with low-pressure sand casting method and milling experiments are performed with uncoated carbide tools using different cutting speeds and feeds. Statistical analysis is used to correlate the machining parameters to surface integrity. It is found that there is a strong dependence of the cutting conditions on machinability and a process window is determined.

Keywords: A201-T7, machinability, milling, surface integrity

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33 A Proposal of Farm-Based Tourism within the Context of Rural Tourism: Zeytinseli

Authors: Vedat Acar, Osman Eralp Çolakoğlu

Abstract:

In this research, with reference to specialization of travel agencies being an important part of tourism industry, a project has been presented about a small-scale enterprise, called as Zeytinseli, contributing actively from the beginning to the end of the production process of olive and olive oil within the context of rural tourism. For this purpose in the research done, firstly, conceptual framework has been formed about travel agency, tour operatorship, specialized travel agency and rural tourism and the necessity of specialization on tourism has been emphasized in today's world. Afterwards, "olive", having an important role in both mythology and divine religions, has been handled within the scope of rural tourism. The cost of accommodation units about Zeytinseli operating in Didim, being a district of Aydın, has been calculated within the context of the project and a fifteen-day's tour to this enterprise has been presented at the end of this project. The research may be said to be an original research on account of embodying not only ecotourism, agro tourism but also cultural tourism and special interest tourism.

Keywords: agro tourism, rural tourism, specialization of travel agency, special interest tourism

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32 Assessment of Base Station Radiation Pollution in Areas of Sheep and Goat Farms in Konya-Turkey

Authors: Selda Uzal Seyfi, Levent Seyfi

Abstract:

The technological devices are more often being used days by day. Thus, electro magnetic pollution is being more important now than last decades. Especially mobile phones and their base stations are subject to assessment in respect of all living beings health as well as of human beings. In this context, it is worth to evaluate the situation of electromagnetic radiation exposing living beings such as animals. In this study, electromagnetic radiation levels to which sheep are exposed in Konya/Turkey are presented. The electromagnetic radiation is measured at 1800 MHz for GSM base stations. 1085 sheep farms are determined in areas of Konya center region (Selçuklu, Meram, and Karatay) in which sheep and goat breeding is widely carried out. In this study, 790 sheep and goat farms, 10.8 % for total farms in Konya region (7276), having more than 100 animals are assessed. Then, the data obtained are depicted. As a conclusion, the results should be evaluated together with the future measurements to determine the exact effect on health of sheep and their productivity.

Keywords: electromagnetic pollution, sheep housing, sheep and goat farm, environmental pollution

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31 A Light in the Road of Protection of Civilians: Responsibility to Protect

Authors: Zeynep Selin Acar

Abstract:

In the world of wars, it is aimed to find ways to protect civilians propound by political elites. Current threats may come from edges of the security concerns, meaning uncontrollable terrorist groups, unanticipated government-supported armed groups or separatists, and unimaginable merge of the previous with foreign supports or oppositions of which could flow into all groups– flaws of international state system. These threats resulted in transformation of inter-state system into a world system with distinctive actors and brought along the changes in strategic plans of political and military bodies, as well as adaptations of principles framing the strategies in terms of may-be-applicable international law constrained by ethical considerations. This paper aims to analyse the Responsibility to Protect (RtoP), being one of those, with its criteria aiming to regulate military interventions taking the protection of civilians both as the reason for intervention, jus ad bellum or right to war, and as the duties during the intervention, jus in bello or how to conduct the war. In addition it will discuss the rise of its bindingness in terms of Responsibility Not to Veto (RNtoV), Franco/Mexican Political Declaration opened in signature for UN member states on September 2015.

Keywords: civilian protection, protection as responsibility, responsibility to protect, responsibility not to veto

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30 The Effect of Group Counseling Program on 9th Grade Students' Assertiveness Levels

Authors: Ismail Seçer, Kerime Meryem Dereli̇oğlu

Abstract:

This study is conducted to determine the effects of group counseling program on secondary school 9th grade students’ assertiveness skills. The study group was formed of 100 students who have received education in Erzurum Kültür Elementary School in 2015-2016 education years. RAE-Rathus Assertiveness Schedule developed by Voltan Acar was applied on this group to gather data. 40 students who got lower grades from the inventory were divided randomly into experimental and control groups. Each group is formed of 20 students. Group counseling program was carried out on the experimental group to improve the students’ assertiveness skills for 8 weeks. Single-way and two-way analysis of covariance (ANCOVA) were used in the analysis of the data. The data was analyzed by using the SPSS 19.00. The results of the study show that assertiveness skills of the students who participate in the group counseling program increased meaningfully compared to the control group and pre-experiment. Besides, it was determined that the change observed in the experimental group occurred separately from the age and socio-economic level variables, and it was determined with the monitoring test applied after four months that this affect was continued. According to this result, it can be said that the applied group counseling program is an effective means to improve the assertiveness skills of secondary school students.

Keywords: high school, assertiveness, assertiveness inventory, assertiveness education

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29 The Relationship between Public Relations and Media Relations: The Case of Hotel Enterprises

Authors: Burcu Oksuz, Volkan Altıintas, Zulfiye Acar Senturk

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Though in the academic literature, it is emphasized that Public Relations (PR) should not be seen only as media relations, in practise, the media relations has a very dominant position at the communication studies carried out by many companies. There are many PR practitioners who have journalism background. However the number of the practitioners who have started to work in the sector after having PR education at the universities has been highly increasing. Therefore, it can be said that previous journalist dominance has diminished at the public relations sector in Turkey. However, by virtue of the fact that some companies and practitioners consider the media coverage the first priority of PR, this much is certain that the dominant position of media relations is ongoing. On the other hand, still many companies measure the success of their PR by how much place their companies have taken. This situation creates major pressure on the PR practitioners to have close relations with the media members and to make them write articles about their companies. Thereupon, PR practitioners have to take the time for the media relations and the media relations comes into prominence more than the other PR functions. The aim of this study is to reveal the PR functions at the companies and to evaluate the position of the media relations in the PR studies. Therefore, it is aimed to find out at what extend the discourse of “Public relations is not media relations” is accepted in practice and actualised. Accordingly, a research about 15 hotel enterprises which are located in the city of İzmir will be carried out. İzmir as one of the most important tourism destinations has many hotels. The PR/corporate communications managers will be interviewed profoundly within the scope of this study and PR functions performed by hotels will be discussed in details in consideration of the datum obtained.

Keywords: media relations, public relations, public relations practitioners, Turkey

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28 Distribution of Maximum Loss of Fractional Brownian Motion with Drift

Authors: Ceren Vardar Acar, Mine Caglar

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In finance, the price of a volatile asset can be modeled using fractional Brownian motion (fBm) with Hurst parameter H>1/2. The Black-Scholes model for the values of returns of an asset using fBm is given as, 〖Y_t=Y_0 e^((r+μ)t+σB)〗_t^H, 0≤t≤T where Y_0 is the initial value, r is constant interest rate, μ is constant drift and σ is constant diffusion coefficient of fBm, which is denoted by B_t^H where t≥0. Black-Scholes model can be constructed with some Markov processes such as Brownian motion. The advantage of modeling with fBm to Markov processes is its capability of exposing the dependence between returns. The real life data for a volatile asset display long-range dependence property. For this reason, using fBm is a more realistic model compared to Markov processes. Investors would be interested in any kind of information on the risk in order to manage it or hedge it. The maximum possible loss is one way to measure highest possible risk. Therefore, it is an important variable for investors. In our study, we give some theoretical bounds on the distribution of maximum possible loss of fBm. We provide both asymptotical and strong estimates for the tail probability of maximum loss of standard fBm and fBm with drift and diffusion coefficients. In the investment point of view, these results explain, how large values of possible loss behave and its bounds.

Keywords: maximum drawdown, maximum loss, fractional brownian motion, large deviation, Gaussian process

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27 Assessing the Adaptive Re-Use Potential of Buildings as Part of the Disaster Management Process

Authors: A. Esra İdemen, Sinan M. Şener, Emrah Acar

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The technological paradigm of the disaster management field, especially in the case of governmental intervention strategies, is generally based on rapid and flexible accommodation solutions. From various technical solution patterns used to address the immediate housing needs of disaster victims, the adaptive re-use of existing buildings can be considered to be both low-cost and practical. However, there is a scarcity of analytical methods to screen, select and adapt buildings to help decision makers in cases of emergency. Following an extensive literature review, this paper aims to highlight key points and problem areas associated with the adaptive re-use of buildings within the disaster management context. In other disciplines such as real estate management, the adaptive re-use potential (ARP) of existing buildings is typically based on the prioritization of a set of technical and non-technical criteria which are then weighted to arrive at an economically viable investment decision. After a disaster, however, the assessment of the ARP of buildings requires consideration of different/additional layers of analysis which stem from general disaster management principles and the peculiarities of different types of disasters, as well as of their victims. In this paper, a discussion of the development of an adaptive re-use potential (ARP) assessment model is presented. It is thought that governmental and non-governmental decision makers who are required to take quick decisions to accommodate displaced masses following disasters are likely to benefit from the implementation of such a model.

Keywords: adaptive re-use of buildings, disaster management, temporary housing, assessment model

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26 Preparation and Antioxidant Activity of Heterocyclic Indole Derivatives

Authors: Tunca Gul Altuntas, Aziz Baydar, Cemre Acar, Sezen Yılmaz, Tulay Coban

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Free radicals, which are generated in many bioorganic redox processes, play a role in the pathogenesis of several diseases including cancer, arthritis, hemorrhagic shock, inflammatory, cardiovascular, neurodegenerative diseases and age-related degenerative brain diseases. Exposures of normal cell to free radical damages several structures, oxidizes nucleic acids, proteins, lipids, or DNA. Compounds interfere with the action of reactive oxygen species might be useful in prevention and treatment of these pathologies. A series of indole compounds containing piperazine ring were synthesized. Coupling of indole-2-carboxylic acid with monosubstituted piperazines was accomplished with 1,1’-carbonyldiimidazole (CDI) in a good yield. The structures of prepared compounds were verified in good agreement with their 1H NMR (nuclear magnetic resonance), MS (mass spectrophotometry), and IR (infrared spectrophotometry) characteristics. In this work, all synthetized indole derivatives were screened in vitro for their antioxidative potential against vitamin E (α-tocopherol) using different antioxidant assays such as superoxide anion formation, lipid peroxidation levels in rat liver, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) stable radical scavenging activity. The synthesized compounds showed various levels of inhibition compared to vitamin E. This may give promising results for the development of new antioxidant agents.

Keywords: antioxidant, indoles, piperazines, reactive oxygen species

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25 Water Quality Determination of River Systems in Antalya Basin by Biomonitoring

Authors: Hasan Kalyoncu, Füsun Kılçık, Hatice Gülboy Akyıldırım, Aynur Özen, Mehmet Acar, Nur Yoluk

Abstract:

For evaluation of water quality of the river systems in Antalya Basin, macrozoobenthos samples were taken from 22 determined stations by a hand net and identified at family level. Water quality of Antalya Basin was determined according to Biological Monitoring Working Party (BMWP) system, by using macrozoobenthic invertebrates and physicochemical parameters. As a result of the evaluation, while Aksu Stream was determined as the most polluted stream in Antalya Basin, Isparta Stream was determined as the most polluted tributary of Aksu Stream. Pollution level of the Isparta Stream was determined as quality class V and it is the extremely polluted part of stream. Pollution loads at the sources of the streams were determined in low levels in general. Due to some parts of the streams have passed through deep canyons and take their sources from nonresidential and non-arable regions, majority of the streams that take place in Antalya Basin are at high quality level. Waste water, which comes from agricultural and residential regions, affects the lower basins of the streams. Because of the waste water, lower parts of the stream basins exposed to the pollution under anthropogenic effects. However, in Aksu Stream, which differs by being exposed to domestic and industrial wastes of Isparta City, extreme pollution was determined, particularly in the Isparta Stream part.

Keywords: Antalya basin, biomonitoring, BMWP, water quality

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24 Investigation of the Effect of Plasticization Temperature on Polymer Thin Film Stability through Spin Coating Process

Authors: Bilge Bozdogan, Selda T. Sendogdular, Levent Sendogdular

Abstract:

We report a technique to control chain conformation during the plasticization process to achieve homogeneous and stable thin films, which allows to reduce post-process annealing times along with enhanced properties like controlled irreversible adsorbed layer (Guiselin brushes) formation. In this study, spin coating temperature was considered as a parameter; hence, all equipment, including the spin coater, substrate, vials, and the solution, was kept inside the same heated fume hood where solution was spin-coated after the temperature was stabilized at a desired value. AFM and SEM results revealed severe difference for solid and air interface between ambient and temperature-controlled samples, which suggest that enthalpic contribution dynamically helps to control film stability in a way where chain entanglements and conformational restrictions are avoided before film growing and allowing to control grafting density through spin coating temperature. The adsorbed layer was also characterized with SEM and Raman-spectroscopy technique right after seeding the adsorbed layer with gold nanoparticles. Stabilized gold nanoparticles and their surface distribution manifest the existence of a controllable polymer brush structure. Acknowledgments: This study was funded by Erciyes University Scientific Research Projects (BAP) Funding(Project ID:10058)

Keywords: chain stability, Guiselin brushes, polymer thin film, spin coating temperature

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23 A Two-Week and Six-Month Stability of Cancer Health Literacy Classification Using the CHLT-6

Authors: Levent Dumenci, Laura A. Siminoff

Abstract:

Health literacy has been shown to predict a variety of health outcomes. Reliable identification of persons with limited cancer health literacy (LCHL) has been proved questionable with existing instruments using an arbitrary cut point along a continuum. The CHLT-6, however, uses a latent mixture modeling approach to identify persons with LCHL. The purpose of this study was to estimate two-week and six-month stability of identifying persons with LCHL using the CHLT-6 with a discrete latent variable approach as the underlying measurement structure. Using a test-retest design, the CHLT-6 was administered to cancer patients with two-week (N=98) and six-month (N=51) intervals. The two-week and six-month latent test-retest agreements were 89% and 88%, respectively. The chance-corrected latent agreements estimated from Dumenci’s latent kappa were 0.62 (95% CI: 0.41 – 0.82) and .47 (95% CI: 0.14 – 0.80) for the two-week and six-month intervals, respectively. High levels of latent test-retest agreement between limited and adequate categories of cancer health literacy construct, coupled with moderate to good levels of change-corrected latent agreements indicated that the CHLT-6 classification of limited versus adequate cancer health literacy is relatively stable over time. In conclusion, the measurement structure underlying the instrument allows for estimating classification errors circumventing limitations due to arbitrary approaches adopted by all other instruments. The CHLT-6 can be used to identify persons with LCHL in oncology clinics and intervention studies to accurately estimate treatment effectiveness.

Keywords: limited cancer health literacy, the CHLT-6, discrete latent variable modeling, latent agreement

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22 A Comparative Study: Influences of Polymerization Temperature on Phosphoric Acid Doped Polybenzimidazole Membranes

Authors: Cagla Gul Guldiken, Levent Akyalcin, Hasan Ferdi Gercel

Abstract:

Fuel cells are electrochemical devices which convert the chemical energy of hydrogen into the electricity. Among the types of fuel cells, polymer electrolyte membrane fuel cells (PEMFCs) are attracting considerable attention as non-polluting power generators with high energy conversion efficiencies in mobile applications. Polymer electrolyte membrane (PEM) is one of the essential components of PEMFCs. Perfluorosulfonic acid based membranes known as Nafion® is widely used as PEMs. Nafion® membranes water dependent proton conductivity which limits the operating temperature below 100ᵒC. At higher temperatures, proton conductivity and mechanical stability of these membranes decrease because of dehydration. Polybenzimidazole (PBI), which has good anhydrous proton conductivity after doped with acids, as well as excellent thermal stability, shows great potential in the application of high temperature PEMFCs. In the present study, PBI polymers were synthesized by solution polycondensation at 190 and 210ᵒC. The synthesized polymers were characterized by FTIR, 1H NMR, and TGA. Phosphoric acid doped PBI membranes were prepared and tested in a PEMFC. The influences of reaction temperature on structural properties of synthesized polymers were investigated. Mechanical properties, acid-doping level, proton conductivity, and fuel cell performances of prepared phosphoric acid doped PBI membranes were evaluated. The maximum power density was found as 32.5 mW/cm² at 120ᵒC.

Keywords: fuel cell, high temperature polymer electrolyte membrane, polybenzimidazole, proton exchange membrane fuel cell

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21 Bacteremia Caused by Nontoxigenic Vibrio cholerae in an Immunocompromised Patient in Istanbul, Turkey

Authors: Fatma Koksal Çakirlar, Si̇nem Ozdemir, Selcan Akyol, Revazi̇ye Gulesen, Murat Gunaydin, Nevri̇ye Gonullu, Belkis Levent, Nuri̇ Kiraz

Abstract:

Vibrio cholerae O1 and O139 are the causative agent of epidemic or pandemic cholera. V. cholerae O1 is generally accepted as a non-invasive enterotoxigenic organism causing gastroenteritis of various severities. Non-O1 V. cholerae can cause small outbreaks of diarrhea due to consumption of contaminated food and water. Particularly, the patients with achlorydria have a risk for vibrio infections. There are numerous case reports of bacteremia caused by vibrio in patients with predisposing conditions like cirrhosis, nephrotic syndrome, diabetes, hematologic malignancy, gastrectomy, and AIDS. We described in this study the first case of nontoxigenic, non-01/non-O139 V. cholerae isolated from the blood culture of a 77-year-old female patient with hipertension, diabetes, coronary artery disease, gout and about 9 years ago migrated breast cancer history. The patient with complaints of shortness of breath, fever and malaise admitted to our emergency clinic were evaluated. There was no diarrhea or abdominal symptoms in the patient. No growth in her urine culture, but blood culture (BACTEC 9120 system, Becton Dickinson, USA) was positive for non-01/non-O139 V. cholerae that was identified by conventional methods and Phoenix automated system (BD Diagnostic Systems, Sparks, MD). It does not secrete the cholera toxin. The agglutination test was negative with polyvalent O1 antisera and O139 antiserum. Empirically ceftriaxone was administered to the patient and she was discharged with improvement in general condition. In this study we report bacteremia by non-01/non-O139 V. cholerae that is rare in the worldwide and first in Turkey.

Keywords: bacteremia, blood culture, immunocompromised patient, Non-O1 vibrio cholerae

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20 Monitoring of Cannabis Cultivation with High-Resolution Images

Authors: Levent Basayigit, Sinan Demir, Burhan Kara, Yusuf Ucar

Abstract:

Cannabis is mostly used for drug production. In some countries, an excessive amount of illegal cannabis is cultivated and sold. Most of the illegal cannabis cultivation occurs on the lands far from settlements. In farmlands, it is cultivated with other crops. In this method, cannabis is surrounded by tall plants like corn and sunflower. It is also cultivated with tall crops as the mixed culture. The common method of the determination of the illegal cultivation areas is to investigate the information obtained from people. This method is not sufficient for the determination of illegal cultivation in remote areas. For this reason, more effective methods are needed for the determination of illegal cultivation. Remote Sensing is one of the most important technologies to monitor the plant growth on the land. The aim of this study is to monitor cannabis cultivation area using satellite imagery. The main purpose of this study was to develop an applicable method for monitoring the cannabis cultivation. For this purpose, cannabis was grown as single or surrounded by the corn and sunflower in plots. The morphological characteristics of cannabis were recorded two times per month during the vegetation period. The spectral signature library was created with the spectroradiometer. The parcels were monitored with high-resolution satellite imagery. With the processing of satellite imagery, the cultivation areas of cannabis were classified. To separate the Cannabis plots from the other plants, the multiresolution segmentation algorithm was found to be the most successful for classification. WorldView Improved Vegetative Index (WV-VI) classification was the most accurate method for monitoring the plant density. As a result, an object-based classification method and vegetation indices were sufficient for monitoring the cannabis cultivation in multi-temporal Earthwiev images.

Keywords: Cannabis, drug, remote sensing, object-based classification

Procedia PDF Downloads 239
19 Analysis of Thermal Effect on Functionally Graded Micro-Beam via Mixed Finite Element Method

Authors: Cagri Mollamahmutoglu, Ali Mercan, Aykut Levent

Abstract:

Studies concerning the microstructures are becoming more important as the utilization of various micro-electro mechanical systems (MEMS) are increasing. Thus in recent years, thermal buckling and vibration analysis of microstructures have been subject to many investigations that are utilizing different numerical methods. In this study, thermal effects on mechanical response of a functionally graded (FG) Timoshenko micro-beam are presented in the framework of a mixed finite element formulation. Size effects are taken into consideration via modified couple stress theory. The mixed formulation is based on a function which in turn is derived via Gateaux Differential scientifically. After the resolution of all field equations of the beam, a potential operator is carefully constructed. Then this operator is used for the manufacturing of the functional. Usual procedures of finite element approximation are utilized for the derivation of the mixed finite element equations once the potential is obtained. Resulting finite element formulation allows usage of C₀ type simple linear shape functions and avoids shear-locking phenomena, which is a common shortcoming of the displacement-based formulations of moderately thick beams. The developed numerical scheme is used to obtain the effects of thermal loads on the static bending, free vibration and buckling of FG Timoshenko micro-beams for different power-law parameters, aspect ratios and boundary conditions. The versatility of the mixed formulation is presented over other numerical methods such as generalized differential quadrature method (GDQM). Another attractive property of the formulation is that it allows direct calculation of the contribution of micro effects on the overall mechanical response.

Keywords: micro-beam, functionally graded materials, thermal effect, mixed finite element method

Procedia PDF Downloads 97
18 Spectral Mixture Model Applied to Cannabis Parcel Determination

Authors: Levent Basayigit, Sinan Demir, Yusuf Ucar, Burhan Kara

Abstract:

Many research projects require accurate delineation of the different land cover type of the agricultural area. Especially it is critically important for the definition of specific plants like cannabis. However, the complexity of vegetation stands structure, abundant vegetation species, and the smooth transition between different seconder section stages make vegetation classification difficult when using traditional approaches such as the maximum likelihood classifier. Most of the time, classification distinguishes only between trees/annual or grain. It has been difficult to accurately determine the cannabis mixed with other plants. In this paper, a mixed distribution models approach is applied to classify pure and mix cannabis parcels using Worldview-2 imagery in the Lakes region of Turkey. Five different land use types (i.e. sunflower, maize, bare soil, and cannabis) were identified in the image. A constrained Gaussian mixture discriminant analysis (GMDA) was used to unmix the image. In the study, 255 reflectance ratios derived from spectral signatures of seven bands (Blue-Green-Yellow-Red-Rededge-NIR1-NIR2) were randomly arranged as 80% for training and 20% for test data. Gaussian mixed distribution model approach is proved to be an effective and convenient way to combine very high spatial resolution imagery for distinguishing cannabis vegetation. Based on the overall accuracies of the classification, the Gaussian mixed distribution model was found to be very successful to achieve image classification tasks. This approach is sensitive to capture the illegal cannabis planting areas in the large plain. This approach can also be used for monitoring and determination with spectral reflections in illegal cannabis planting areas.

Keywords: Gaussian mixture discriminant analysis, spectral mixture model, Worldview-2, land parcels

Procedia PDF Downloads 158