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101.
基于珠三角部分地区乡村景观的保护与发展策略存在的不足,研究论证了英国景观特征评估将有助于改善乡村景观更新中“场所感”缺失的问题。通过解读针对我国尤其是珠三角地区的景观特征评估理论研究和实践的不足,结合珠三角乡村的景观导控现状,提出将英国景观特征评估方法进行本土转译,用于我国珠三角地区乡村的途径、要点和形式。该途径可用于珠三角乡村多个场所尺度的景观特征评估,将助力于珠三角乡村景观的保护与发展策略。 相似文献
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中国已步入生态文明建设的新时期,美丽中国和美丽乡村建设是生态文明体系构建的重要组成部分,也是生态文明理论指导下的实践载体。新时期乡村景观的内涵、构成与特征已发生深刻变化,维护乡村景观地方性特征与性格是未来乡村规划的重要途径和共同愿景,而识别与评价乡村景观特征与性格的关键在于其表征体系的构建。基于新时期乡村景观的认知,以景观C-3P理论体系为基础框架建立了一套融合时空特征的多要素、多尺度、多维度的景观特征与性格表征体系。景观要素决定了景观环境的语境特征,景观要素表征是对要素单体属性信息的直观描述;景观特征表征是融合景观空间格局、景观空间过程、景观空间感知3个维度的完整表达;景观性格表征是对各类景观特征在景观空间中相互作用所呈现出的效用与效应的典型刻画。通过对表征体系中关键指标的测度与评价可以揭示出乡村景观空间的整体特征与地方性格,以此作为乡村景观规划与管理的重要技术支撑。 相似文献
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This study aims to investigate the defensible character of the Lahore railway station built in response to “the war of independence in 1857,” which greatly impacted the location and design of the building. This study demonstrates the integral role played by the railway station in the development of the new colonial city, which the British wants to be defensive in every aspect. Railways were introduced in Pakistan (India) soon after their inauguration in Britain. Beginning from the mode of transportation, the multifaced contribution of railways toward the urban growth, new architectural style, mode of construction, and technology cannot be recanted. The research is based on the documentation and analysis of the history of Lahore railway station design. First, this study uses primary and secondary data to offer a history of the Lahore railway station from its inception to final execution. Second, it explores the criteria adopted by the British for its site selection to make the station a defensible post. The research finding includes the visual features that enhanced the architectural character of the building. Qualitative methods are used including several other approaches, namely, literature review, archival data collection, analysis of photographs, and study of architectural drawings and old maps, to achieve the objectives. 相似文献
106.
《International Journal of Hydrogen Energy》2020,45(60):35053-35063
This report evaluates a new family of pyridine containing aromatic polyether sulfones as polymer electrolytes for high temperature polymer electrolyte membrane fuel cells (HTPEM FCs). The polymers are prepared by high temperature polyetherification reactions, yielding highly soluble polymers even with pyridine contents as high as 90%. Along with the pyridine content, crosslinking density is also tuned, leading to the enhancement of membrane properties such as film integrity, dimensional stability and doping ability in acidic media. The completion of the crosslinking reaction is enabled by a short thermal pre-treatment, preceding the doping step in H3PO4 85%. Both the linear and the crosslinked membranes show high thermal and oxidative stability. Membranes before and after crosslinking are integrated in single cells where their conductivity and performance are monitored, revealing conductivities above 7 × 10−2 S/cm at temperatures higher than 180 °C. 相似文献
107.
In this paper, a multiple model optimal tracking control (MOTC) design method for the double fed induction generator (DFIG) using correlative measured technique is proposed. The DFIG is represented by a third-order model, where electro-magnetic transients of stator are neglected. By using the correlative measured technique, the correlative measured matrix (CMM) of wind power system is obtained firstly. Then, a nonstandard state space equation of DFIG is obtained with the correlative measured vectors (CMVs), which reflect interactions between the DFIGs and grid. In order to cope with nonlinearities and continuous variation in the operating points, a multiple model design method is proposed in the discrete domain. The obtained control law, synthesized by using Bayesian probability, only depends on the local measured parameters. Hence, the MOTC can be regarded as a decentralized coordinated control, which can simplify the control structure and improve the transient stability of DFIG. To illustrate the effectiveness of the proposed MOTC strategy, simulations on a hybrid wind thermal power (HWTP) system are performed. The results show that the proposed MOTC strategy can provide acceptable performance throughout the whole operating region. Comparing to the conventional PID control, transient stability, damping, and fault ride-through capability of DFIG with the proposed MOTC design method have been improved effectively. 相似文献
108.
The electrical characteristics of Al/strained Si-on-insulator (sSOI) Schottky diode have been investigated using current–voltage (I–V) and capacitance–voltage (C–V) measurements in the wide temperature range of 200–400 K in steps of 25 K. It was found that the barrier height (0.57–0.80 eV) calculated from the I–V characteristics increased and the ideality factor (1.97–1.28) decreased with increasing temperature. The barrier heights determined from the C–V measurements were higher than those extracted from the I–V measurements, associated with the formation of an inhomogeneous Schottky barrier at the interface. The series resistance estimated from the forward I–V characteristics using Cheung and Norde methods decreased with increasing temperature, implying its strong temperature dependence. The observed variation in barrier height and ideality factor could be attributed to the inhomogeneities in Schottky barrier, explained by assuming Gaussian distribution of barrier heights. The temperature-dependent I–V characteristics showed a double Gaussian distribution with mean barrier heights of 0.83 and 1.19 eV and standard deviations of 0.10 and 0.16 eV at 200–275 and 300–400 K, respectively. From the modified Richardson plot, the modified Richardson constant were calculated to be 21.8 and 29.4 A cm−2 K−2 at 200–275 and 300–400 K, respectively, which were comparable to the theoretical value for p-type sSOI (31.6 A cm−2 K−2). 相似文献
109.
Present paper proposes a new technique based on double parametric form of fuzzy numbers to solve an uncertain beam equation using Adomian decomposition method subject to unit step and impulse loads. Uncertainties appear in the initial conditions are considered in terms of triangular convex normalized fuzzy sets. Using the single parametric form viz. α-cut form of fuzzy numbers, the fuzzy beam equation is converted first to an interval based fuzzy differential equation. Next this differential equation is transformed to crisp form by applying double parametric form of fuzzy numbers. Finally the same is solved by Adomian decomposition method symbolically to obtain the uncertain bounds of the dynamic response. Obtained results are depicted in term of plots to show the efficiency and powerfulness of the present analysis. 相似文献
110.
Manish Aggarwal 《国际智能系统杂志》2019,34(5):733-753
Attitudinal Choquet integral (ACI) extends Choquet integral (CI) through a consideration of a decision-maker's (DM's) attitudinal character. In this paper, we generalize ACI, and the resulting operator is termed as generalized ACI (GACI). GACI adds to the efficacy of the ACI in the representation of a DM's unique and complex attitudinal character. It also generates a vast range of exponential ACI operators, such as harmonic ACI, ACI, quadratic ACI, to name a few. We further present induced GACI to consider additional information that may be associated with the arguments of aggregation. The special cases of the proposed operators are investigated. The usefulness of the proposed operators in modelling human decision behavior is shown through a case study. 相似文献