Istanbul Technical University

About: Istanbul Technical University is a education organization based out in Istanbul, Turkey. It is known for research contribution in the topics: Fuzzy logic & Large Hadron Collider. The organization has 12889 authors who have published 25081 publications receiving 518242 citations. The organization is also known as: İstanbul Teknik Üniversitesi & Technical University of Istanbul.

Visible Light Initiated Free Radical Promoted Cationic Polymerization Using Acylgermane Based Photoinitiator in the Presence of Onium Salts

Abstract: The cationic polymerization of cyclohexene oxide (CHO) was achieved by UV irradiation (λ = 350−420 nm) of methylene chloride solutions containing benzoyltrimethylgermane (BTG) and onium salts, such...

Use of information and communication technologies by small and medium‐sized enterprises (SMEs) in building construction

Abstract: Scholars usually agree that small and medium‐sized enterprises (SMEs) active in construction are not very innovative when compared with large‐size construction enterprises. This is particularly evident in the case of adoption and diffusion of innovation associated with information and communication technologies (ICTs). Although ICTs are powerful instruments for the rapid and broader diffusion of technical knowledge, few SMEs are fully able to exploit their benefits. There is little evidence of how SMEs perceive ICTs and of the extent to which these technologies are actually used in the construction industry. There is a relationship between organizational size and the use of ICTs within the SMEs in the building construction sector in Turkey. A set of ICT variables comprising the perception, investment, usage and the software preferences of SMEs were analysed by making use of the data collected in a survey of a randomly selected sample of 227 building construction firms in Turkey. In contrast to the common ...

Block bootstrap for Mann–Kendall trend test of serially dependent data

Abstract: Mann–Kendall (MK) test for trend detection must be modified when the data are serially correlated, to prevent the detection of false trends. Various approaches are developed for this purpose, such as prewhitening, trend-free prewhitening, variance correction and block bootstrap. Each method has its own Type I and Type II errors. In this study, the errors of block bootstrapping MK test are estimated by a simulation study and compared with other methods. Optimal block length that minimizes the Type I error is determined as function of sample size and autocorrelation coefficient. It is shown that the power of block bootstrapping MK test is comparable with those of other modified MK tests. These tests are applied to some annual streamflow series with trend recorded in Turkish rivers, and their powers are compared. A modified form of the trend-free prewhitening procedure is proposed that has a smaller Type I error. Copyright © 2011 John Wiley & Sons, Ltd.

Photoinduced Free Radical Promoted Copper(I)-Catalyzed Click Chemistry for Macromolecular Syntheses

Abstract: Photoinduced copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC) via photoinduced electron transfer using free radical photoinitiators has been developed as a new platform to serve as orthogonal click system. Photoinitiators acting at near UV and visible range, namely 2, 2-dimethoxy-2-phenyl acetophenone, 2-benzyl-2-dimethylamino-4′-morpholino butyrophenone, 2,4,6-trimethylbenzoyl)diphenylphosphine oxide, dicyclopentadienyl bis[2,6-difluoro-3-(1-pyrrolyl)phenyl] titanium) and camphorquinone/benzyl alcohol were tested with copper(II) chloride/N,N,N′,N″,N″-pentamethyldiethylenetriamine complex to catalyze the CuAAC via photoinduced electron transfer reaction. This strategy has been applied in construction of various macromolecular architectures including telechelic polymers and block copolymers. Spectroscopic and chromatographic investigations revealed that successful macromolecular syntheses have been achieved by this technique.