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81.
Abstract

Housing prices have increased substantially in some emerging markets in recent years. Turkish housing market has also experienced a boom over the last decade with rapid house price appreciations. This study is the first to employ two different house price indexes to analyze housing bubble in Turkey in two different time periods, 2010:M1–2014:M12 and 2007:M6–2014:M12. We first capture the determinants of housing price by employing Bounds test and then examine whether rising house prices have been justified by fundamentals by employing OLS/FMOLS/DOLS, Kalman filter and ARIMA models. The Bounds test results suggest that there is a long-term cointegration among house price indexes and housing rent, construction cost and real mortgage interest rate. The results imply that the Turkish housing market has experienced some cases of overvaluation, but not bubble formation. This evidence has several implications for house price dynamics and risks in the Turkish housing market. Based on Turkish experience, the study also draws policy implications for emerging housing markets.  相似文献   
82.
This work presents the synthesis and characterization of a new water‐soluble oligophenol derivative, 4‐(2‐hydroxybenzylideneamino)benzenesulfanilic acid (OSAL‐SA) and its metal complexes. The chemical structure of the water‐soluble polymer was characterized by nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FTIR) spectroscopies and thermogravimetric analyses (TGAs). Pb(II), Cu(II), Co(II) complexes of the polymer were also synthesized in methanol. Characterizations of water insoluble polymer‐metal complexes were performed by FTIR, flame atomic absorption spectroscopy, and TGA. The conductivity measurements of OSAL‐SA and polymer–metal complexes were carried out by the four‐probe technique. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
83.
A hydrogen fuel cell vehicle requires fuel cells, batteries, supercapacitors, controllers and smart control units with their control strategies. The controller ensures that a control strategy predicated on the data taken from the traction motor and energy storage systems is created. The smart control unit compares the fuel cell nominal output power with the vehicle power demand, calculates the parameters and continually adjusts the variables. The control strategies that can be developed for these units will enable us to overcome the technological challenges for hydrogen fuel cell vehicles in the near future. This study presents the best hydrogen fuel cell vehicle configurations and control strategies for safe, low cost and high efficiency by comparing control strategies in the literature for fuel economy.  相似文献   
84.
This paper describes a fully automated method of measuring the magnetization characteristics (flux linkage versus current and position) of switched-reluctance (SR) motors. The measuring scheme was developed using a graphical programming environment (LabVIEW), a data acquisition card, and external interface hardware. The graphical programming method allows a high degree of software modularity and provides the features needed fur sensor zero adjustment, data acquisition and analysis, and automated presentation of results. Furthermore, the experimental setup described in this paper can be used to obtain the magnetization characteristics of other electromechanical devices. Experimentally measured results from a test SR motor using the scheme are presented in the paper  相似文献   
85.
In this study, an overview has been presented a classification of the vehicles using hydrogen with different ways. The using of hydrogen in vehicles has been categorized into two main categories as designs in which hydrogen is burned and energy is generated by conversion to electricity. The designs of internal combustion vehicles with using hydrogen via burning, the designs of the fuel cell vehicles that using hydrogen by converting into electricity and their hybrid versions have been introduced. In the automotive industry, the structure and future advantages of hydrogen fuel cell electric vehicles have been handled in a separate title. Onboard storage, safety, the capital cost and operating cost of the different design of vehicles have been analyzed rigorously.  相似文献   
86.
87.
Siliconcarbide (SiC) ceramic powder incorporated inorganic–organic nanocomposites were prepared by sol–gel spin coating method. Coating properties and abrasion resistance of the hybrid polymers were examined by scanning electron microscopy (SEM), EDX analysis, FT-IR spectroscopy, thermogravimetric differential thermal analysis (TG-DTA). Mechanical tests like surface static corrosion analysis, abrasion test, scratch-tape test, adhesion test, chemical and solvent resistance, surface hardness were performed in order to evaluate the coatings for possible industrial applications. Prepared polymers were applied onto the aluminium substrates. Results revealed that industrially available SiC ceramic powder incorporated inorganic–organic nanocomposites can be prepared with an easy and controlled way using sol–gel method and applied onto the aluminium surfaces by spin coating without using primer solution and shows excellent abrasion resistance.  相似文献   
88.
The effects of heating method and temperature on physical, structural and photocatalytic behaviors of TiO2 pellets prepared by conventional heating and hot isostatic pressing have been evaluated. The pellets of submicron TiO2 powders were heated to 600, 650, 700, 750 and 1000 °C using both processing methods in order to compare anatase to rutile phase transformation and densification behaviors. Bulk densities and porosities were calculated using the Archimedes method. XRD analysis were performed to calculate anatase/rutile ratios. Microstructures were characterized using SEM. Photocatalytic experiments have been performed under full spectrum irradiation. Degraded methylene blue samples were periodically monitored through UV–vis spectrophotometer to determine degradation kinetics. Anatase to rutile transformation is slightly faster and densification is better for lower temperatures for conventional heating, however HIPing gives better densification above 750 °C as it also retards rutile transformation. Mixed phase structures and HIPed samples showed the best photocatalytic performance which makes this method advantageous.  相似文献   
89.

In recent years, tampering and altering of digital images have become easier with the rapid development of computer technologies such as digital image editing tools. Therefore, verification of image integrity and tamper detection of digital images have become a great challenge. Fragile watermarking is the most widely used method for protecting the integrity and content authenticity of the image. In this paper, by using SHA-256 hash function, a novel block based fragile watermark embedding and tamper detection method is proposed. In watermark embedding phase, host image is divided into 32?×?32 non-overlapped blocks. Each 32?×?32 block is then divided into four 16?×?16 nonoverlapped sub-blocks. The entire hash value of the first three sub-blocks is generated as a watermark using SHA-256 hash function. The generated 256-bit binary watermark is embedded into the least significant bits (LSBs) of the fourth sub-block and watermarked image is obtained. In tamper detection phase, the detection of tampered block has been performed by comparing the hash value obtained from the three sub-blocks with the extracted watermark from the fourth sub-block of the watermarked image. The performance of the proposed method has been evaluated by applying linear and nonlinear attacks to the different regions of the watermarked images. Experimental results show that the proposed method detects all the tampered regions of the attacked images and high visual quality of watermarked images has been obtained.

  相似文献   
90.
A new algorithm for sensorless operation of permanent magnet motors   总被引:2,自引:0,他引:2  
In this paper, the authors propose and investigate a new algorithm for shaft position sensorless operation of permanent magnet motors, based on flux linkage and line current estimation. Measured line current and terminal voltage are used to estimate the flux linkage of the motor. The algorithm has a two current-loop structure, with the outer loop used to correct the position, and the inner loop utilised to correct the estimated flux linkage. The theoretical basis of the algorithm and individual definition of the system blocks is explained. Dependencies on motor parameters and measurement errors are discussed to show the effectiveness of the method using real data. As well as giving a detailed explanation of the new algorithm, the paper presents a wide range of computed and experimental results, demonstrating the reliability of the method even during acceleration of the motor from rest  相似文献   
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