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In this study, a bond-slip model is proposed to take into account the effects of corrosion on the bond characteristics between extremely low-strength concrete and plain reinforcing bars. The proposed bond-slip model is based on reversed cyclic lateral loading tests of nearly full-scale reinforced concrete columns with reinforcing bars corroded to different levels. The columns taken into consideration during the current study were part of an extensive experimental program designed to study the performance of older columns at Istanbul Technical University. The columns were representative of a large number of underperforming reinforced concrete buildings prone to seismic actions throughout the world. Test results demonstrated that the corrosion of reinforcing bars had a significant effect on the strength and deformability characteristics of substandard reinforced concrete columns subjected to the combined actions of axial and reversed cyclic lateral loads. Taking this aspect into consideration, a novel bond-slip model is established to estimate the variation in bond strength degradation and the bond strength as a function of the level of corrosion of the reinforcing bars. Furthermore, the predictions of the proposed model are also verified with experimental results from the literature. [ABSTRACT FROM AUTHOR]

This paper analyzes the passenger-carpooling potential among undergraduate students using a model for estimating choice based on combined revealed and stated preference data. The data are obtained from a survey performed at four campuses of Istanbul Technical University. The case in focus is carpooling as a passenger; carpooling as a driver is deliberately left out because of students' lack of familiarity with it. The hypothetical passenger-carpooling scenarios lead to enquiries about the fee students are willing to pay and the distance they are willing to walk to a designated pick-up location. The estimation results show that females and frequent campus travelers are more likely to prefer passenger carpooling. The scenario analysis included in the paper reveals the prioritization of carpool fee over walking distance to pick-up locations among undergraduate students. [ABSTRACT FROM AUTHOR]

The purpose of this study is to test the applicability of k 0 -INAA method at the Istanbul Technical University TRIGA Mark II research reactor. The neutron spectrum parameters such as epithermal neutron flux distribution parameter ( α ), thermal to epithermal neutron flux ratio ( f ) and thermal neutron flux ( φ th ) were determined at the central irradiation channel of the ITU TRIGA Mark II research reactor using bare triple-monitor method. HPGe detector calibrations and calculations were carried out by k 0 -IAEA software. The α , f and φ th values were calculated to be −0.009, 15.4 and 7.92·10 12 cm −2 s −1 , respectively. NIST SRM 1633b coal fly ash and intercomparison samples consisting of clay and sandy soil samples were used to evaluate the validity of the method. For selected elements, the statistical evaluation of the analysis results was carried out by z -score test. A good agreement between certified/reported and experimental values was obtained. [ABSTRACT FROM AUTHOR]

Environmental risk is a measure of potential threats to the environment and combines the probability that events will cause or lead to degradation of the environment and the severity of that degradation. Evaluation of environmental risk factors requires linguistic terms to be used rather than exact numerical assignments. The fuzzy set theory provides a useful tool for converting linguistic terms into numerical evaluations. In this article, we will try to select the best location for the Faculty of Management of the Istanbul Technical University taking care of the predetermined environmental criteria by using fuzzy TOPSIS. The decision matrix is composed of linguistic evaluations for the alternatives with respect to the environmental risk criteria. The Macka Campus area has been selected after the multicriteria evaluation. A sensitivity analysis is also realized to see if the minor changes in criteria weights cause any change in the ranking of alternatives. Unless the importance of the criteria rock or soil structure, remoteness to health facilities, transportation availability, and transportation costs is changed to be from low to extremely low importance, the Macka Campus is still the selected alternative. [ABSTRACT FROM PUBLISHER]

This paper aims to describe the modification of the radial beam port of ITU (İstanbul Technical University) TRIGA Mark II research reactor for BNCT applications. Radial beam port is modified with Polyethylene and Cerrobend collimators. Neutron flux values are measured by neutron activation analysis (Au–Cd foils). Experimental results are verified with Monte Carlo results. The results of neutron/photon spectrum, thermal/epithermal neutron flux, fast group photon fluence and change of the neutron fluxes with the beam port length are presented. [ABSTRACT FROM AUTHOR]

The current study aimed to investigate the relationship between Internet addiction and problem solving skills of university students. The study also examined the psychometric properties of the Turkish version of Problematic Internet Entertainment Use Scale for Adolescents, which centers on major Internet entertainments such as online video games and social networking sites, specifically with regard to normative, reliability, and validity information. Problem Solving Inventory was utilized in order to measure the problem solving skills of students. Both instruments were administered to 371 students aged 17 to 36 years from different departments in Marmara University and Istanbul Technical University (Istanbul, Turkey). This study showed that the Turkish version of the Problematic Internet Entertainment Use Scale for Adolescents was a reliable and valid instrument for measurement of maladaptive patterns in the use of online entertainments such as OVG and SNS. The results revealed that there is a close relationship between problematic internet entertainment use and Avoidant ( r = 443; p < .01) and Impulsive problem solving styles ( r = .402; p < .01) among university students. [ABSTRACT FROM AUTHOR]

This study investigates the potential effects of parking pricing on the private vehicle use of residents of the campuses of large compounds such as universities. For this purpose, a parking pricing model is estimated for the academicians working at the Ayazaga Campus of Istanbul Technical University. Similar to many campus areas, the major problems of this campus are the insufficiency of parking supply and the campus's contribution to the congestion on the surrounding road network. The study combines revealed and stated preference data obtained from a questionnaire, estimates a mode choice model in order to explore responses to different parking pricing scenarios and execute willingness-to-pay analysis. The analyses show that significant switches to mass transit modes can be sustained if parking pricing is introduced. [ABSTRACT FROM AUTHOR]

It is mentioned about the parametric experiments for deep reactive ion etching (DRIE) method for n type, <100> oriented, 100mm (milimeter) Silicon as a subtrate and SU8-3050 negative photo resist as a mask material in this study. DRIE process is performed in plasma that is produced by two RF (Radio Frequency) power sources with the additional specific etch gases under the high vacuum atmosphere. DRIE method is widely used in micro electro mechanical systems (MEMS) industry to produce high aspect ratio micro structure with etch rates. The effects of six different DRIE variables on Si and SU8 etch rate were observed within this experimental study. This variables are: Chamber pressure (mTorr), RF plasma power (Watt), RF platen power (Watt), SF6 gas flow rate (ml/s) as main etch gas, O2 gas flow rate (ml/s), He gas flow rate ml/s. The experiment was performed with ICP plasma etching device in Istanbul Technical University Micro Electromechanic Systems for Biological Applications (BIO-MEMS) Laboratory. The results were measured by a stylus profile meter device. [ABSTRACT FROM AUTHOR]

This publication is derived from a PhD thesis that aims to explore the possible reflections of the design domains on the students' design behavior by analyzing the similarities and differences between the computer-aided and conventional architectural design process. The focus of this study is on conceptual and overall design decisions in these two different cases. A comprehensive literature review was conducted before starting to design the research method. Theoretical concepts and empirical findings were revised with the focus on possible dimensions of measurement, analysis and evaluation methodologies. It was concluded that there is a lack consensus in the research area. Although there is a variety of unstructured observations and assumptions about computer-aided design process, only a limited number of empirical studies have been carried out in the related research area. In all of the empirical studies, computer aided architectural design (CAAD) process was evaluated in comparison to the conventional design process. Thus, different descriptions of the design activity by different researchers were reviewed and considered in all research phases, especially while determining the preliminary and final dimensions of measurement. A hybrid theoretical model is used to combine two major approaches to design research (rational problem solving by Herbert A. Simon and reflectionin- action by Donald A. Schön) for investigating the design process. After the general survey of former empirical research on CAAD, it was decided to conduct a controlled experiment with two conditions: first experimental condition (E01), the subjects were obliged to design with the software they prefer while participants in the control condition (E02) were only allowed to utilize only conventional tools. The sample population was determined as senior students of Istanbul Technical University, Faculty of Architecture. This decision was based on the homogeneity of design expertise and software use among the students, shared design terminology between the researcher and the students, high accessibility of subjects and possibility of contributing to the architectural design approaches in ITU. The duration of the experiment was defined as 120 minutes, considering time length of the previous studies and feasibility issues. The experiments were conducted in ITU Faculty of Architecture and a total of 1890 minutes of protocol recordings were obtained. In terms of the number of participants and length of the experiments, this research is one of the most comprehensive studies ever undertaken among the indexed publications. The design problem for the experiment was formulated considering the characteristics of the research question, sample population, the duration of the experiment and the problems that were used in similar surveys. The problem description is decided to be relatively short in order to motivate the participants to restructure and redefine requirements. Analysis of the experiments revealed that there is significant difference between the means of total number of design decisions in conventional design and CAAD conditions. Moreover, in certain experimental sessions, the design decisions were found to be differently organized in time. These observations may be related to the unique properties of CAAD media. The potential of the medium to create automated reproductions, complex representations and rich visual content may have led the subjects to focus more on the design process and the medium itself. The expertise level of the students that participated CAAD experiments may also have affected the findings, as their awareness in this area is lower than professional architect. Another possible reason of the difference in the mean number of decisions on design process can be the fact that sketching is a goal-directed automatic behavior. In contrast, CAAD processes require human computer interaction, conscious reasoning, thinking about the tools and process planning. The interactive nature of the medium may be shifting the focus of the subjects to the process itself, as they are obliged to use a certain format, which can be transformed, processed and stored by the computer. It is important to note that findings of this study are generalizable only to a limited domain as they are limited with the number and profiles of participating students and specific to the design problem and setup used in the experiments. All of the observations reflect the conceptual design phase; therefore, they cannot be generalized to the whole design process. Further research on the use of digital domains in the design process is needed for a clearer insight into architectural education and professional practices. [ABSTRACT FROM AUTHOR]

Small and medium size enterprises (SMEs) have an important impact on the development of new economy but SMEs have a need for venture capital (VC) and initial public offerings (IPOs) in order to grow. Therefore, It is very important to know how owners, managers and employees in the SMEs perceive the VC and IPOs in Turkey. A questionnaire is developed to understand these types of perceptions via focus groups. The questionnaire is distributed to the owners, managers and employees of SMEs that operate in Istanbul Technical University KOSGEB, Bogazici University KOSGEB and Yıldız Technical University KOSGEB. [ABSTRACT FROM AUTHOR]

The historical town of Elmalı, situated on the Taurus Mountains near Antalya, attracts attention by its wellpreserved urban establishment. This paper considers the Urban Conservation Project of the Historical Site of Elmalı Town that was formulated in the Spring Term of 2005-2006 Academic Year at the Graduate Program in Restoration at Istanbul Technical University. An intensive research on the historical, cultural and architectural background of Elmalı was carried out in order to understand the relations of the physical environment of the site and the urban identity. The collaborative observations on the site and the analysis of the site based on certain categories were then developed into proposals to rehabilitate the site. [ABSTRACT FROM AUTHOR]

Istanbul Technical University student Nil Ünal picked up an award in the MA category at Mannheim''s Euro PM2008 for her thesis on the effect of boron carbide in tungsten matrix composites… [Copyright &y& Elsevier]

Presents parts of results of an experimental research project on the behavior of end-plate connections subjected to monotonic and cyclic loading conducted at Istanbul Technical University. Test program; Strength predictions; Evaluation of the experimental results and the strength predictions.