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Pavements constructed for the purpose of meeting the demand of highways which were emerged with the improving technological developments increased. And consequently, more resources were demanded to be directed to pavement maintenance and rehabilitation. Hereby, the concept of pavement management emerged. Although project-level analyses were found adequate previously, network-level evaluations were needed in order to do detailed planning as a result of resource allocation and transfer problems that were emerged later. Therefore, pavement management system has become compulsory for all pavements to be controlled together. In this framework, programming is needed in order to schedule maintenance–rehabilitation and develop costs with respect to budget. In the study carried out, a mode was developed in order to program the routine network maintenance activities in terms of Pavement Maintenance and Management Systems, and it was concluded that this problem can be solved through ant colony, using Visual Basic.  相似文献   
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Electricity sector has grown substantially in Turkey since the early 1960s as a result of rapid industrialization and urbanization. The vertically integrated state-owned company had a legally established monopoly on the generation, transmission and distribution of electricity in Turkey. With the support and encouragement of international organizations like the World Bank, Turkey has initiated a comprehensive program to liberalize and privatize the electricity market in 2001. The liberalization of the electricity market in Turkey started in the distribution side of the market. The distribution network was divided into 21 distribution regions and in each of these, separate – initially state-owned – distribution companies have been authorized to distribute and sell electricity. The plan envisaged to complete privatization of all distribution companies until the end of 2006. This study compares the welfare implication of privatization of the distribution networks by comparing two extreme cases, a pure regional distributional monopoly case and a representative pure “free” consumer case, with a benchmark case of administered price regulation. For this purpose, we develop a simulation model of the Turkish electricity system, and use the data on generation and distribution costs. Our simulation analysis shows that substantial welfare losses occur if the distributional companies behave as regional monopolists. Our findings reiterate the importance of regulation and market design.  相似文献   
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The accuracy of ultrasonography to measure fat thickness (FT) and longissimus dorsi muscle (LM) traits (area, depth and width) in live Awassi male lambs and predict carcass FT and LM traits was studied.Twenty six Awassi male lambs were randomly divided into light (L) (n = 13) and heavy (H) (n = 13) finishing lambs. Slaughter weight of lambs in L and H groups were 40 and 45 kg, respectively. FT and LM traits, cross-sectional area between the 12th and 13th rib were measured using real-time ultrasound in vivo and on the carcass after slaughter. All ultrasound and carcass measurements were the same except live weight (LW) (P < 0.001), cold carcass weight (CCW) (P < 0.001) and carcass LM width (P < 0.05). Overall, correlation coefficients between ultrasound and carcass FT, LM depth, width and area were 0.79, 0.82 (P < 0.001); 0.60, 0.58 (P < 0.05); 0.48, −0.17 (P > 0.05) and 0.89, 0.87 (P < 0.001), respectively, for lambs in L and H groups. The introduction of ultrasound FT and ultrasound LM area as independent variables in addition to LW in the multiple regression equations further improved the variations for carcass FT (84%, 71%), carcass LM area (79%, 79%), CCW (72%, 65%) for lambs in light and heavy groups whereas no improvement was observed for carcass yield.These results indicate that in vivo ultrasound FT and measurement of the LM area in association with LW could be used to estimate carcass FT, carcass LM area and CCW in different LW Awassi lambs.  相似文献   
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This paper firstly reports the effect of deoxyribonucleic acid (DNA) molecules extracted from chickpea and wheat plants on the injection/recombination of photogenerated electrons and sensitizing ability of dye‐sensitized solar cells (DSSCs). These high‐yield DNA molecules are applied as both linker bridging unit as well as thin tunneling barrier (TTB) at titanium dioxide (TiO2 )/dye interface, to build up high‐efficient DSSCs. With its favorable energy levels, effective linker bridging role, and double helix structure, bifunctional DNA modifier shows an efficient electron injection, suppressed charge recombination, longer electron lifetime, and higher light harvesting efficiency, which leads to higher photovoltaic performance. In particular, a photoconversion efficiency (PCE) of 9.23% is achieved by the binary chickpea and wheat DNA‐modified TiO2 (CW@TiO2) photoanode. Furthermore, time‐resolved fluorescence spectroscopy measurements confirm a better electron transfer kinetics for DNA‐modified TiO2 photoanodes, implying a higher electron transfer rate (kET). This work highlights a great contribution for the photoanodes that are linked with DNA molecule, which act as both bridging unit and TTB to control the charge recombination and injection dynamics, and hence, boost the photovoltaic performance in the DSSCs.  相似文献   
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In medical and personal health systems for vital sign monitoring, contact-free remote detection is favourable compared to wired solutions. For example, they help to avoid severe pain, which is involved when a patient with burned skin has to be examined. Continuous wave (CW) radar systems have proven to be good candidates for this purpose. In this paper a monolithic millimetre-wave integrated circuit (MMIC) based CW radar system operating in the W-band (75–110?GHz) at 96?GHz is presented. The MMIC components are custom-built and make use of 100?nm metamorphic high electron mobility transistors (mHEMTs). The radar system is employing a frequency multiplier-by-twelve MMIC and a receiver MMIC both packaged in split-block modules. They allow for the determination of respiration and heartbeat frequency of a human target sitting in 1?m distance. The analysis of the measured data is carried out in time and frequency domain and each approach is shown to have its advantages and drawbacks.  相似文献   
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The core drilling method has often been used to determine the current status of asphalt concretes. However, this method is destructive so causes damage to the asphalt concretes. In addition, this method causes localized points of weakness in the asphalt concretes and is time consuming. In recent years, non-destructive testing methods have been used for pavement thickness estimation, determination of elasticity modulus, and density and moisture measurements. In this study, the above-mentioned non-destructive and destructive tests with data obtained by applying the Marshall stability to the same asphalt concretes were estimated using the artificial neural networks approach.  相似文献   
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