西北地区节水灌溉市场与技术需求

西部开发需要大量的生态用水，从节水灌溉设备市场分析，节水灌溉专用泵阀、新型输水管材、高效低能喷微灌设备及材料的需求量很大，技术需求与亟待研究开发的关键技术和设备也很多。从西北地区水资源状况与需求看，节水灌溉市场有很大潜力。     

近40年来中国西北内陆5个典型湖泊面积变化遥感分析

在全球气候变暖的背景下,研究中国西北内陆地区湖泊的面积变化不仅对水资源管理和可持续发展战略有着重要意义,也为评价气候变化与人类活动对湖泊的影响提供参考。以中国西北内陆区5个典型湖泊为研究对象,利用1970-2015年的Landsat MSS/TM/ETM+/OLI影像数据,利用归一化差异水体指数(Normalized Difference Water Index,NDWI)和改进型归一化差异水体指数(Modified Normalized Difference Water Index,MNDWI)分别提取5个典型湖泊边界并获取湖泊面积,同时利用5个典型湖泊周边的气象站降雨量、蒸发量等气象数据,尝试分析湖泊面积发生变化的原因。结果表明:红碱淖近30年来面积呈减小趋势,入湖河流拦蓄和煤炭地下开采等是导致面积减少的原因;博斯腾湖近40年来的面积呈先增加后减少的趋势,其面积变化主要受地表径流和积雪融水的影响;呼伦湖近40年来面积呈减少的趋势,其面积变化主要受入湖径流量的影响;贝尔湖近30年来呈相对稳定的趋势,其面积变化主要入湖径流量的影响;青海湖近40年来面积呈现先减小后增大的趋势,其面积变化主要受区域降水和入湖径流量的影响。     

西北地区农业干旱对气象干旱的时空多角度响应

采用标准化降水蒸散指数和标准化土壤水指数分别表征气象干旱和农业干旱,基于干旱事件三维识别和气象干旱与农业干旱事件对的匹配结果,利用Copula函数条件概率分布和贝叶斯网络概率模型分析了西北地区农业干旱对气象干旱的时空多角度响应关系。结果表明：基于线性、非线性关系模型及Copula函数条件概率分布确立了西北地区农业干旱对气象干旱的干旱历时、干旱烈度、干旱面积及干旱迁移距离间最优响应关系分别为二次多项式模型、基于Frank Copula函数的非线性关系模型、指数模型和线性模型;建立的气象、农业干旱变量间的响应概率特征曲线可定量预测西北地区不同程度的气象干旱发展为农业干旱的概率;已知气象干旱特征条件下,根据最优响应关系及响应概率特征曲线可对农业干旱特征及其发生概率进行可靠预测。     

西北省间实时平衡电力市场探索

新能源出力的波动性和随机性影响电网实时平衡.中国西北电网新能源占比高、平衡资源时空分布不均衡,分省市场实时平衡困难,为此,文中设计西北省间实时平衡电力市场,以发挥西北省间实时平衡能力,适应高比例新能源电网实时平衡需要.首先,结合国内外电力市场建设与西北实时平衡现状,分析了建立西北省间实时平衡市场的必要性;然后,说明了双边竞价的市场运作思路,提出了基于潮流的市场耦合方法的市场竞价出清模型,设计了市场运作流程;最后,讨论了西北省间实时平衡市场与其他市场之间的协调运作,通过模拟算例说明了西北省间实时平衡市场的作用.     

"东南天子气"之演生与江南区域政治格局的形成

长江流域一如黄河流域是中国文明的发源地,然而,自先秦至两汉,中国政治的重心是在黄河流域,但在这一历史的漫长岁月中,江南地区因得天独厚的区位优势,政治势力的演生不断加剧。汉魏之际,随着中原统一王朝的崩溃,江南地区便日益成为传承中原封建文明的正朔所在。着重探寻秦汉四百年间,江南地区政治势力与区域格局形成的历史过程及其深刻影响。     

西安通远坊天主教会建筑群的历史沿革及其艺术特征初探

通远坊天主教会建筑群位于西安市高陵县,是清代西北地区天主教总堂,现存的四座建筑天主堂、修女堂、圣心小修道院和育婴堂均建于清末民初,地域特征显著,建造做法肖似,作为一个整体清晰地反映出了当地的匠作传统。本文通过梳理其历史沿革,分析其艺术特征,希望将这一珍贵的内陆天主教文化遗产展示于世人面前。     

Residents' preferences for private amenities and trade-offs associated with various spatial densities and patterns

ABSTRACT

Northwest Arkansas planning policies, like a number of communities across the country, have identified goals working toward more sustainable, livable, and subsequently denser development patterns. However, the understanding of residents’ perceptions of such living arrangements is limited. This study provides a more nuanced understanding of Northwest Arkansas residents’ spatial preferences through a survey of residents’ preferences for private amenities and their trade-off with various spatial densities and patterns in support of sustainability. Results of the survey indicate a preference for, and experience with, single-family residential living arrangements and amenities, with the preponderance (80%) of survey respondents currently living in single-family housing. There is a preference for low-density neighborhoods even if it means sacrificing other amenities. This study is in alignment with previous research suggesting that people may learn to prefer where they live. Additionally, while the majority of survey respondents indicated a preference for communal greenspaces, renters are more likely to prefer communal greenspaces when compared to homeowners. This study indicates that attached, multi-family development and renter development in Northwest Arkansas should consider the provision of communal green spaces, walkable access to transit, and walkable access to services as desired amenities for those residents.     

Spatio-temporal analysis of precipitable water vapour over northwest china utilizing MERSI/FY-3A products

Northwest China is considered as the arid and semi-arid temperate continental climate, where the precipitation is closely related to precipitable water vapour (PWV) content. In this paper, the Medium-Resolution Spectral Imager (MERSI) water vapour products were first used to study the spatial and temporal characteristics of water vapour over Northwest China, which were developed by the National Satellite Meteorological Center of China from the Chinese second-generation polar orbit Meteorological Satellite Fengyun 3A (FY-3A). In order to utilize the MERSI water vapour products, the MERSI 5 min water vapour product is compared respectively with global positioning system (GPS), Aerosol Robotic Network (AERONET) and Radiosonde water vapour data in situ datasets. The results show that the water vapour values of the MERSI product are a slightly lower than referenced data, and the accuracy of MERSI product compared with GPS water vapour is the most agreeable, with a mean absolute percentage error (MAPE) of 22.83%. The PWV content displays a typical spatial distribution pattern in Northwest China that it is the highest in the southeast, the second for the northwest and the lowest in the south-centre. The water vapour content over each province in a descending order is Shaanxi, Ningxia, west of Inner Mongolia, Xinjiang, Gansu and Qinghai. The seasonal variation of water vapour content over Northwest China appears to be lowest in winter, followed by spring, then for autumn, and highest in summer. The PWV content of each province in Northwest China shows the periodic inner-annual variation, that is, the PWV content is lowest in January, and gradually increases with time till it peaks in July, and then decreases monthly afterwards, which agrees with the quadratic polynomial model by months. The standard deviation of the water vapour content in summer is 0.533–1.027 mm, while that in winter is 0.262–0.527 mm.     

本土营造——西北地区低碳生态乡镇的低技术策略

针对当前我国低碳生态城镇实践过分依赖“高技术、高投入”而难以实施的问题,结合西北地区乡镇发展的现实困境,本文提出西北地区乡镇低碳生态的理想路径为：探索一条具有地域适宜性的”低技术”策略,进而通过对西北地区乡镇碳排放特征的分析,提出加强对乡镇建设性碳排放的控制是西北地区乡镇实现低碳生态目标的关键。最后结合西北地区乡镇的地域特质,依托西安建筑科技大学在地域生态建筑与现代生土材料科学等领域的研究基础,提出：本土营造是降低乡镇建设性碳排放的有效途径,并提出其在规划与管理中的推广、应用策略。     

膨胀管技术在西北油田TH10233CH井的应用

侧钻是降低油气开采成本的有效途径之一。西北油田受井眼尺寸、避水要求、不稳定泥岩、复杂压力体系等原因的影响,侧钻难度极大。为解决这一难题,在TH10233CH井采用膨胀管技术进行了实际应用。采用φ139.7mm膨胀管封固上部不稳定地层,膨胀管膨胀前内径124.2mm,膨胀后内径可达134.5mm,采用φ130mm钻头钻进,顺利完钻。膨胀管钻井技术在TH10233CH井的成功应用对西北油田侧钻井钻进具有重大指导意义。