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排序方式: 共有1241条查询结果,搜索用时 31 毫秒
31.
2013年以来“城乡统一的建设用地市场”已成为土地制度改革的中心议题,但这一制度仍受困于“计划性”的城乡建设用地的指标总控以及耕地(尤其是基本农田)指标控制。基于此,对于基层政府而言,辖区内的基于城乡建设用地的利益格局与基于基本农田保护的责任格局产生了智识与政策层面上的双重分裂,而“耕保型村庄”长期作为一个失语者则未得到应有的追踪与调研。文章以珠江三角洲的佛山市南海区为例,借由案例村庄的深度访谈来折射其对于农村土地制度改革(尤其是农村集体经营性建设用地)的期望以及对于耕地保护经济补偿的诉求,期望能对新一轮次的城乡统筹发展与村庄规划有所启发。 相似文献
32.
Xian Xue Xiaofeng Yuan Rong Ma Qibin Yuan Hong Wang 《Journal of the European Ceramic Society》2019,39(13):3744-3748
In this study, the novel temperature-stable (1-x)Ag2MoO4-xAg0.5Bi0.5MoO4 microwave dielectric ceramics were prepared by a modified solid-state reaction method. The phase composition, microstructures and microwave dielectric properties of the (1-x)Ag2MoO4-xAg0.5Bi0.5MoO4 ceramics were investigated. All the compounds can be sintered well at ultra-low temperatures (<540 °C). The XRD and SEM analysis indicate that the Ag2MoO4 and the Ag0.5Bi0.5MoO4 can coexist with each other. When x = 0.65, the ceramics exhibit the best microwave dielectric properties with a relative permittivity of 23.9, a Q × f value of 16,200 GHz (at 7.3 GHz) and a near-zero TCF value of -2.4 ppm/°C at 520 °C. The results indicate that temperature-stable (1-x)Ag2MoO4-xAg0.5Bi0.5MoO4 ceramics are promising candidates for low temperature co-fired ceramics (LTCC) applications. 相似文献
33.
The present paper deals with the development of lead zirconate titanate (PZT) fibres, pearls and fibre fragments, for their use as active phase in piezocomposites. As new a approach, the green ceramic components are shaped by polysulphone spinning, allowing for effective and flexible forming over a wide range of different geometries and sizes. The correlation between processing parameters, e.g. the slurry composition, nozzle size and operation velocity, and the resultant shape of ceramic components is analysed. Sintered piezoceramic parts show a dense microstructure. Performance data are evaluated on PZT/epoxy composites. Measurement results of strain, polarisation and piezoelectric coupling are given and discussed. The developed PZT components are seen as key for the creation of smart and lightweight structural components. Further, free formed PZT components open new design approaches for sensing and actuating devices and ultrasound transducers. 相似文献
34.
《Journal of Great Lakes research》2022,48(3):659-668
Previous studies reported coastal trapped waves (CTWs) in the Caspian Sea (CS). This study deals with the generation mechanisms, the temporal and spatial variability of CTWs in this area, and their transformations during propagation from the origin to the destination using recent measurements and high-resolution numerical simulations. CTWs are observed at all stations with periods of 2–6 days after northerly storms. The Absheron Peninsula, old Sefidrud delta, and Nur coasts were identified as the CTWs prone regions. The generation of CTWs in these locations was confirmed using numerical experiments. The propagation away from the generating location of CTWs was analyzed using a representative real wind storm. In the west part of the CS, the generation mechanism of CTWs is mainly similar to the barotropic Kelvin waves; in contrast, it is similar to the continental shelf waves in the southern shelves. The results can be used to study the contribution of generated CTWs to the transport of sediment and biological materials in all large lakes. 相似文献
35.
The objectives of this research are to design and develop a practical decision support methodology with efficient prediction tool and risk assessment analysis of a terrorism insurgency situation. The proposed methodology consists of two main parts as: (1) the prediction modelling and (2) risk assessment analysis. The Improvised Explosive Device (IED) incidents from 2007 to 2013 in the capital district of Yala province, the southern part of Thailand, are collected and generated to the methodology as a case study implementation. The proposed methodology is capable of indicating and illustrating the risk assessment prediction results of terrorism insurgency incidents. Furthermore, the demonstration of the Explosive Ordnance Disposal Mobile Unit (EODMU) based upon a Risk Assessment Radar Chart is investigated. In practical terms of applying the proposed methodology, the Thai Government can concentrate on a critical operation zone under a Risk Assessment Radar Chart, resulting in a more accurate operation and leading to a much lower number of casualties. 相似文献
36.
Shajay Bhooshan 《Architectural Design》2016,86(2):44-53
Shajay Bhooshan heads up the computation and design ZHACODE group at Zaha Hadid Architects (ZHA) and is a course master at the Architectural Association Design Research Laboratory (AADRL). Here he argues that Parametricism 2.0 has a vital role to play in the progressing of computational design. Assimilating the exploratory developments of the last 15 years, he asserts how the next phase of Parametricism will enable a further consolidation and evolution of digital practices. 相似文献
37.
38.
鄂尔多斯盆地靖边气田南部古风化壳岩溶储层有效性评价 总被引:2,自引:0,他引:2
鄂尔多斯盆地靖边气田南部奥陶系马家沟组马五_(1-2)亚段白云岩储层由于风化岩溶作用形成了复杂的孔隙系统,孔隙结构的复杂性增强了储层的非均质性和各向异性,也增加了储层有效性评价的难度。通过钻井取心和录井资料标定常规测井曲线,结合压汞、铸体薄片、成像测井、核磁共振测井及试气资料,分别从影响储层孔隙结构的岩性、缝洞、物性、平面分布等方面对该层段进行了储层有效性综合评价,形成了一套适合该地区储层的测井有效性评价标准,并建立了具有不同孔隙结构储层的测井识别模式。研究结果表明:岩性较纯的细粉晶云岩孔隙结构较好、缝洞配置良好、基质物性好,因而储层有效性好,产能相对较高;向东和东北倾斜的古地貌对储层的分布具有明显的控制作用.由西向东及由西南向东北方向的储层,其有效性逐渐变差,产能逐渐降低。所得到的储层有效性评价指标在相同岩溶机理形成的其他地区也具有一定的适用性.只需根据具体储层特征和试气结果进行标定,适当调整标准即可使用。 相似文献
39.
Alex McDowell 《Architectural Design》2015,85(4):26-33
Film production requires world building: the power to visualise and bring to life narrative through a film's total environment. This is often entirely speculative, imagining alternative or future worlds. Here, Alex McDowell , acclaimed British production designer, producer and Professor at the University of Southern California (USC) describes his world-building, narrative approach to production design, which he consolidated in the Steven Spielberg film Minority Report (2002) that envisioned Washington DC in the year 2050. The possibilities of this storytelling technique are demonstrated by its transference into real-life projects, such as the immersive model that his production company, 5D GlobalStudio, developed for Al Baydha, a Bedouin village in Saudi Arabia. 相似文献
40.
花城广场与珠江公园同处于广州新城市中心区珠江新城内,相距约1km,都是绿化环境优美的城市大型公共空间。花城广场南端的海心沙岛是举办2010年第十六届亚运会开闭幕式的庆典广场,花城广场已是广州乃至中国家喻户晓的“城市客厅”。2001年10月至2002年3月,中国第四届园林博览会在珠江公园召开。这两处城市公共空间具有相似的区位、规模和绿化环境,但市民对两者的使用频率却差异较大。现对两地的使用情况进行现场调研和问卷调查,将收集到的数据采用频数分析、配对样本参数检验和单因素方差分析方法进行统计分析,发掘普通市民对两者评价满意度差异,进而探讨城市大型公共空间使用频率的影响因素。 相似文献