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1.
This study was conducted to determine the place of historic gardens in the city of Tabriz vis-a-vis Iranian garden arts. It provides information on the historic gardens of Tabriz, which are no longer in existence, for example, ‘Saheb Abad’ Garden, ‘North’ Garden, ‘Sefa’ Garden, ‘Amir Kabir’ Garden, ‘Saheb Divan’Garden and ‘Fath Abad’ Garden, as well as four historical maps belonging to the Qajar era in the city of Tabriz. In this research, the factors influencing the design of El-Goli Garden were studied, which can be grouped into three major categories: physical, biological and cultural. After a brief study of the above factors in the city of Tabriz and its different microclimates, the types of similarities that exist relating to Iranian garden art were determined.  相似文献   
2.
This study, which was conducted on the only surviving garden of the historic gardens in the city of Tabriz in Iran (i.e. the garden of El-Goli), closely examines its importance and place in the Iranian art of gardening. El-Goli garden is considered as an important place in the city by foreign and local tourists. However, in recent years, with the development of Tabriz and consequently the increased need for green space and recreational areas for citizens, this historic garden has become a public promenade and park. This paper examines the risks and threats posed by the change in land use. Since visitors are the main threats, a questionnaire was developed to identify their reasons for visiting the garden, their behaviour in the garden and how they use this historic garden. The questionnaire was completed by 100 visitors who were randomly selected. The table of frequency for each variable was prepared using SPSS software. Finally, the results show that most visitors not only are unaware of the historical value, but also come to the garden for other purposes such as recreation, leisure and use of facilities and so on. Thus, their attitudes and behaviours will pave the way for the destruction of the garden.  相似文献   
3.
Heat exchangers are integral parts of important industrial units such as petrochemicals, medicine and power plants. Due to the importance of systems energy consumption, different modifications have been applied on heat exchangers in terms of size and structure. In this study, a novel heat exchanger with helically grooved annulus shell and helically coiled tube was investigated by numerical simulation. Helically grooves with the same pitch of the helical coil tube and different depth are created on the inner and outer wall of annulus shell to improve the thermal performance of heat exchanger. In the first section, thermal performance of the shell and coil heat exchanger with the helical grooves on its outer shell wall was compared with same but without helical grooves. At the second section, helically grooves created on both outer and inner wall of the annulus shell with different groove depths. The results showed that the heat exchanger with grooves on both inner and outer shell wall has better thermal performance up to 20% compared to the heat exchanger with grooves on only outer shell wall. The highest thermal performance achieves at lower flow rates and higher groove depths whereas the pressure drop did not increase significantly.  相似文献   
4.
Simulations of biological macromolecules have evolved tremendously since the discoveries of the 1970s. The field has moved from simple simulations in vacuo on picosecond scales to milliseconds of accurate sampling of large proteins, and it has become a standard tool in biochemistry and biophysics, rather than a dedicated theoretical one. This is partly due to increasing computational power, but it would not have been possible without huge research efforts invested in new algorithms and software. Here, we illustrate some of this development, both past and future challenges, and in particular, discuss how the recent introduction of modern ensemble methods is breaking the trend of ever-longer simulations to instead focus on throughput and sampling. This has not only helped simulations become much more accurate, but it provides statistical error estimates, which are critical, as simulations are increasingly used to predict properties that have not yet been measured experimentally.  相似文献   
5.
For a digital color camera to represent the colors in the environment accurately, it is necessary to calibrate the camera RGB outputs in terms of a colorimetric space such as the CIEXYZ or sRGB. Assuming that the camera response is a linear function of scene luminance, the main step in the calibration is to determine a transformation matrix M mapping data from linear camera RGB to XYZ. Determining M is usually done by photographing a calibrated target, often a color checker, and then performing a least‐squares regression on the difference between the camera's RGB digital counts from each color checker patch and their corresponding true XYZ values. To measure accurately the XYZ coordinates for each patch, either a completely uniform lighting field is required, which can be hard to accomplish, or a measurement of the illuminant irradiance at each patch is needed. In this article, two computational methods are presented for camera color calibration that require only that the relative spectral power distribution of the illumination be constant across the color checker, while its irradiance may vary, and yet resolve for a color correction matrix that remains unaffected by any irradiance variation that may be present. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 540–548, 2014  相似文献   
6.
Bioreactors have great potential in the successful development of tissue‐engineered heart valve replacements, both at the research stage and in commercial platforms. Their ability to mimick the chemical and physiological conditions of the body has allowed researchers to study in vitro cellular responses, and this has helped in the fabrication of better and more efficient tissues in vivo. Use of different bioreactors, such as, rotating, dynamic flexure, cyclic stretch and pulsatile bioreactors, in tissue engineering of heart valves has been widely investigated. However, this research is still at its early stage, and many critical issues need to be resolved to make tissue engineered heart valves sufficiently reliable for clinical applications. In the following article, after a brief introduction to the structure and role of heart valves, the efforts of tissue engineers in designing heart valves using different bioreactors is described. © 2015 Society of Chemical Industry  相似文献   
7.
Large deflection of a cantilever beam subjected to a tip-concentrated load is governed by a non-linear differential equation. Since it is hard to find exact or closed-form solutions for this non-linear problem, this paper investigates the aforementioned problem via the differential transformation method (DTM) and the variational iteration method (VIM), which are well-known approximate analytical solutions. The mathematical formulation is yielded to a non-linear two-point boundary value problem. In this study, we compare the DTM and VIM results, with those of Adomian decomposition method (ADM) and the established numerical solution obtained by the Richardson extrapolation in order to verify the accuracy of the proposed methods. As an important result, it is depicted from tabulated data that the DTM results are more accurate in comparison with those obtained by the VIM and ADM, which is one of the objectives of this article. Moreover, the effects of dimensionless end point load, ??, on the slope of any point along the arc length and the dimensionless vertical and horizontal displacements are illustrated and explained. The results reveal that these methods are very effective and convenient in predicting the solution of such problems, and it is predicted that the DTM and VIM can find a wide application in new engineering problems.  相似文献   
8.
A high performance thermostable α-amylase at low pH values has been synthesized. Sugarcane bagasse was hydrolyzed in a dilute acid solution and utilized as carbon source for the growth of Aspergillus niger strain NCIM 548. Glucose, xylose and arabinose with the ratio of 1.0: 0.9: 0.3 (w/w/w) were detected in the hydrolyzate by HPLC analysis. Optimization of the fermentation conditions for α-amylase production was performed by varying four influential parameters such as Sugarcane bagasse hydrolyzate (SBH), NH4Cl, pH and incubation time using a central composite design (CCD) under response surface methodology (RSM). The optimum values of SBH, NH4Cl, pH and incubation time were 20.49, 2.34 g/l, 5.65 and 76.67 h, respectively. The acido-thermophilic enzyme showed maximum stability at 70°C and pH value of 4. The rate constant, K m and maximum reaction rate, V max were 18.79 g/l and 15.85 g/l·min, respectively.  相似文献   
9.
10.
Ultrathin strained-Si/strained-Ge heterostructures on insulator have been fabricated using a bond and etch-back technique. The substrate consists of a trilayer of 9 nm strained-Si/4 nm strained-Ge/3 nm strained-Si on a 400-nm-thick buried oxide. The epitaxial trilayer structure was originally grown pseudomorphic to a relaxed Si0.5Ge0.5 layer on a donor substrate. Raman analysis of the as-grown and final transferred layer structures indicates that there is little change in the strain in the Si and Ge layers after layer transfer. These ultrathin Si and Ge films have very high levels of strain (∼1.8% biaxial tension and 1.4% compression, respectively), and are suitable for enhanced-mobility field-effect transistor applications.  相似文献   
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