水资源承载能力评价的熵权模糊物元模型

以模糊物元分析理论为基础,结合熵值法和欧氏贴近度概念,构建用于评价水资源承载能力的熵权模糊物元分析模型。介绍了该模型的计算步骤,应用该模型对淮河流域各分区的水资源承载能力进行了综合评价,并与其他评价方法的评价结果进行了比较。结果表明,该文建立的模型合理且计算简单,可靠性、实用性强,适用于多种综合评价问题。     

基于模糊物元模型的城市活力评价

将熵值理论与模糊物元理论相结合,建立了基于熵权的城市活力评价模糊物元模型,并将该模型应用于江苏省沿江15个县级城市的活力评价研究。结果表明,处于苏南地区且靠近上海都市圈的4个县级市的城市活力水平相对领先于其他县级市。究其原因,涉及区位条件、政治经济、历史文化等影响因素,进而提出经济、制度与空间3方面的沿江城市发展对策,以实现区域协调发展。模糊物元城市活力评价模型的建立为城市活力评价提供了一种考虑多因素的综合方法。     

基于可拓理论的城市用地适用性评估

依据可拓理论中的物元理论及关联函数,建立城市用地适用性评估的关联度及物元模型,采用可拓物元模型对5个评估单元的用地适用性进行评估,并与模糊综合评判法进行比较分析.研究表明:可拓评估通过可拓关联度判断城市用地适用性属于某集合的程度,而且关联函数能够根据数据特征挖掘数据信息,避免了权重确定的主观性;可拓评估结果不但与模糊综合评判法完全一致,而且更为精细.     

福建省第三产业发展的区域比较分析

运用可拓工程方法和主成分分析方法建立了福建省第三产业发展水平的综合评判物元模型。模型的输出结果表明：福建省各地区第三产业发展水平差距悬殊；综合关联度将第三产业发展水平划分成4个等级，单指标关联度则揭示了各地区第三产业发展的优、劣势。     

风景名胜区规划方案的层次分析法与熵技术评价

当前我国风景名胜区规划方案的评价 ,基本上都是以定性评价为主 ,评价结果难免带有较大的随意性。如何使风景名胜区规划评审更具科学性和客观性 ,引入定量评估方法和决策模型尤显重要。本文提出将层次分析法与决策中的熵技术结合 ,建立层次熵决策模型 ,由层次分析法确定各评价指标权重 ,用熵技术对所得权重进行修正 ,进一步计算各方案到理想点的距离 ,最终从多方案中选择最佳方案。并以南京幕燕风景名胜区的总体规划方案为例进行了实证研究     

地图质量可拓综合评价模型

可拓学是解决矛盾问题的新兴交叉学科,理论支柱是物元理论和可拓集合。它以物元为基本元,通过物元变换来建立物元模型,化矛盾问题为相容问题。基于可拓论探讨了地图质量的可拓综合评价新模型,即通过构造各评定等级的经典域和全体等级的节域物元矩阵,计算待评物元与各评定等级之间的关联度,判定对各评定等级的符合程度而作出综合评定。文中给出了具体评价流程,并应用于实际地图的质量综合评价,结果同其它方法进行了对比,取得了较好的结果。     

基于可调功效函数容量耦合生态经济协调发展评价模型

依据功效函数和熵值赋权法的原理,改进min-max功效函数和熵值赋权法的计算基础,提出可调可比可预测的功效函数与基于均值功效的熵值赋权法;讨论生态经济协调发展的等级标准,阐明容量耦合系数模型与生态经济协调发展的评价算法;以精简评价指标和鄱阳湖生态经济建设战略思想为指导,建立生态经济协调发展评价指标体系。将生态经济协调发展评价的等级标准、模型算法和指标体系在江西省九江市庐山区加以实际应用,验证模型的适用性。     

Determination of allowable subgrade frost heave with the pavement roughness index in numerical analysis

Frost heave is an upward swelling of soil during cryogenic conditions in cold regions. It is caused by the accumulation of ice crystals in subgrade soil, which grow upwards when freezing temperatures penetrate into the subgrade. This study establishes the allowable soil subgrade frost heave based on the roughness standard of asphalt pavement in China, and aims to balance the pavement design and frost heave resistance of subgrades in cold regions. We formulated a mechanical model of pavement supported by the boundary conditions of differential frost heave, based on the elastic layered system theory. The differential soil subgrade frost heave was modeled as a sinusoidal function, and the allowable frost heave and the roughness index were modeled as the displacement boundaries for the top and bottom of the pavement structure. Then the allowable frost heave was back-calculated according to the roughness standard. Numerical results show that the allowable frost heave depends on the pavement structure, material properties, the highway grade, and other factors. In order to ensure that the actual soil subgrade frost heave is lower than the allowable frost heave, pavement structures and materials need to be selected and designed carefully. The numerical method proposed here can be applied to establish the frost heave resistance of subgrade when the pavement structure and materials are determined.     

城市生态安全水平的物元评判模型研究

作为人口高度集聚的人工生态系统,城市生态系统的安全性更加具有脆弱性。该文选取了若干公认的反映城市生态安全水平指标,建立了类型识别的物元评判模型。应用于我国十大城市,得出以下结论:处于"较安全"的城市有南京市、深圳市、大连市;处于"临界安全"的城市有上海市、广州市、南昌市、合肥市;处于"不安全"的城市有天津市、武汉市。评价结果基本与实地相符,说明建立的物元评判模型是可行的。     

城镇化质量评价指标体系分析

通过对国内有关城镇化发展质量评价的研究文献在发表年代、成果名称及出处、指标主要构成、研究区域、研究方法及指标数据来源等内容的对比分析,梳理出国内城镇化质量评价研究的成果和存在的问题。在此基础上从定量和定性2个方面重新构建城镇化健康发展质量评价指标体系,定量指标体系涵盖经济、社会、资源与环境、公共服务与居民生活及城乡统筹与城乡一体化健康发展5个方面共计60个指标;定性指标体系涵盖城乡发展协调程度和城镇居民满意度2个方面共计32个指标。在测评方法上,学者们常用的熵值法、因子分析法、层次分析法、模糊综合评判法等分析方法均适用于该指标体系。对城镇化质量进行实际测评时,要求定量和定性指标体系同时使用,且测评结果应基本相同。研究成果旨在为科学、全面评价中国城镇化质量提供一套可参考的指标体系。     

区域城市化水平的物元可拓综合评判——以福建省为例

在建立区域城市化水平评价指标体系的基础上,运用物元可拓方法和主成分分析方法,以福建省23个主要城市为研究地域单元,建立了福建省区域城市化水平综合评判模型.模型的输出结果表明,福建省区域城市化水平总体偏低,各地区在发展水平上出现明显分层;模型的综合关联度将福建省区域城市化水平划分成4个等级,分项指标关联度则揭示了各地区城市化发展的薄弱环节.研究结果较为客观地反映了福建省城市化的实际状况,为区域城市化水平的评价提供了一种新的研究思路.     

Laboratory and field performance of recycled aggregate base in a seasonally cold region

The objective of this project was to characterize the freeze-thaw properties of recycled concrete (RCA) and asphalt (RAP) as unbound base and to assess how they behaved in the field for nearly 8 years. This paper includes an examination of existing information, laboratory studies of freeze-thaw behavior, and evaluation of data from MnROAD field-test sections in a seasonally cold region, i.e., in Minnesota, USA. Test sections were constructed using recycled materials in the granular base layers at the MnROAD test facility. One test section included 100% RAP, another 100% RCA, a third one a 50/50 blend of RCA/natural aggregate, and a fourth one only natural aggregate (Class 5) as a control. The stiffness (i.e., elastic modulus) was monitored during construction and throughout the pavement life by the Minnesota Department of Transportation, along with the variation of temperatures and moisture regimes in the pavement to determine their effects on pavement performance. The resilient modulus of each material was determined by bench-scale testing in accordance with NCHRP 1-28a, as well as by field-scale tests incorporating a falling-weight deflectometer. Specimens were subjected to as many as 20 cycles of freeze-thaw in the laboratory, and the change in their resilient modulus was measured. In the field-test sections constructed with the same materials as the base course, temperature, moisture, and field modulus (from falling-weight deflectometer tests) were monitored seasonally for nearly 8 years. From the temperatures in the base course layer, the number of freeze-thaw cycles experienced in the field was determined for each test section. Inferences were made relative to modulus change versus freeze-thaw cycles. Conclusions were drawn for long-term field performances of the recycled base (RAB) in comparison to natural aggregate.     

基于熵权物元模型的土地生态安全评价——重庆市江津区实证

土地生态安全评价是区域生态文明建设以及维护区域生态安全与社会经济可持续发展的基础工作,近年来受到广泛关注。通过构建基于熵权物元模型的土地生态安全评价体系,并以重庆市江津区为案例开展实证研究。结果表明：（1） 江津区土地生态安全形式总体好转,但土地生态安全整体情况较差,还需要进行大力整治。（2） 江津区各乡镇土地生态安全等级具有明显的区域差异性。（3） 重点对土地生态安全状况差的区域进行整改,土地生态安全高的区域需继续保持生态优先的政策导向是下一步政府工作的重点。     

基于可拓学的生态市建设评价——以哈尔滨市为例

生态市建设的评价是衡量生态市规划、建设和管理成效的主要依据。在诠释生态市概念的基础上,基于EES模式和层次分析法构建生态市建设评价指标体系,运用可拓学的物元分析方法构建生态市建设评价的综合评判模型,并以哈尔滨市为例进行了实证研究。结果表明:①从2005年到2008年哈尔滨市生态市建设整体上呈现出由较差向合格跃升的趋势;②噪声环境质量、人口自然增长率成为制约哈尔滨市生态市建设水平的因素;③评价结果与现实情况比较吻合,表明物元分析方法在生态市建设评价中具有较强的可信度。     

2000—2009年重庆市土地资源生态安全评价及趋势分析

针对重庆市土地资源的特点及问题,在国内关于区域土地生态安全研究成果的基础上,基于压力-状态-响应框架模型,构建了一套土地资源生态安全评价指标体系,采用熵权赋权法确定指标权重,运用土地资源生态安全综合模型对该区域2000—2009年的土地生态安全综合指数进行了计算。结果表明,区域土地生态安全综合指数由2000年的0.160升高至2009年的0.695,2000年土地生态安全属于敏感级,2009年则进入良好级,整体生态安全状态呈好转趋势,但土地所受的生态压力整体上有所加大。土地生态安全状况的改善主要依赖于对土地生态环境的治理,现阶段土地的生态压力依然严峻。对2000—2009年的土地生态安全变化进行趋势拟合,显示土地生态安全综合状况已进入快速改善阶段。     

盐城湿地类型演化预测分析

以盐城湿地主要分布的三个县市:射阳、大丰和东台作为研究区,通过1988~2006年每隔6年的4期TM遥感影像,开展盐城湿地类型的动态变化分析,根据遥感影像解译结果,利用基于可拓物元模型的湿地演化元胞自动机(CA)模型和马尔可夫模型从空间和数据上进行湿地类型的变化预测。分析结果表明:(1)将基于可拓物元CA模型模拟预测结果与遥感分类结果进行逐个像元比较,计算得出相似程度达到 70%,因此基于可拓物元CA预测模型引入到湿地类型演化预测中是可行的。(2)基于可拓物元CA模型与马尔科夫模型的数值预测结果具有较高的相似度,表明研究区在2012年养殖场将成为盐城湿地最主要的湿地利用类型,预测结果分别达到了750.06km²和721.96km²,同时,耕地、居民用地、养殖场、米草面积总体呈增长趋势,滩地、芦苇、碱蓬和盐田呈剧烈减少趋势,米草逐渐占据优势物种,大面积的滩涂开发是盐城湿地类型变化最主要的原因。     

熵视角下的中国海洋生态系统可持续发展能力分析

通过对海洋生态系统特征的分析,构建了海洋生态系统可持续发展能力评价指标体系;运用信息熵构建了海洋生态系统可持续发展能力评价模型,分析各个指标对海洋生态系统可持续发展能力的影响,从而提出提高海洋生态系统可持续发展能力的相关性的措施。研究结果显示：2004~2011年,人类对海洋自然生态系统的需求日益加大;在国家和政府的重视下,海洋污染问题得到了改善,海洋生态系统内部朝着有序健康方向发展,自然生态系统的支撑能力不断提高,中国海洋生态系统可持续发展能力总体呈上升趋势。     

Desert pavement development and landscape stability on the Eastern Libyan Plateau, Egypt

Desert pavement surfaces of the eastern Libyan Plateau in central Egypt represent a stable landscape preserving Middle and Upper Paleolithic artifacts. Detailed measurements of pavement clasts indicate significant variability in clast size, density, lithology and orientation between pavements, but no spatial relationship among any of these pavement variables over the study area. Pavement characteristics are unrelated to local geomorphic features including slope gradient and aspect, suggesting a desert pavement surface that has developed without significant influence from transporting mechanisms such as overland flow and slope failure. Meridional vertical cracks in surface clasts implicate thermal stresses due to diurnal solar variation as a mechanical weathering process, whereas the presence of a clast-free silty layer within all soil profiles indicates that these are accretionary pavement surfaces that have grown upward over time. The desert pavement in this region has likely developed in situ through mechanical breakdown of surface clasts and desert pedogenesis, indicating long-term stability for this region and minimal taphonomic effects on artifacts > 2 cm in diameter deposited on this surface over the last ca. 100 ka.     

Cosmogenic He exposure ages of Pleistocene debris flows and desert pavements in Capitol Reef National Park, Utah

The Quaternary history of the Capitol Reef area, Utah, is closely linked to the basaltic-andesite boulder deposits that cover much of the landscape. Understanding the age and mode of emplacement of these deposits is crucial to deciphering the Quaternary evolution of this part of the Colorado Plateau. Using cosmogenic ³He exposure age dating, we obtained apparent exposure ages for several key deposits in the Capitol Reef area. Coarse boulder diamicts capping the Johnson Mesa and Carcass Creek Terraces are not associated with the Bull Lake glaciation as previously thought, but were deposited 180±15 to 205±17 ka (minimum age) and are the result of debris flow deposition. Desert pavements on the Johnson Mesa surface give exposure ranging from 97±8 to 159±14 ka and are 34–96 kyears younger than the boulder exposure ages. The offset between the boulder and pavement exposure ages appears to be related to a delay in pavement formation until the penultimate glacial/interglacial transition or periodic burial and exposure of pavement clasts since debris flow deposition. Incision rates for the Capitol Reef reach of the Fremont River calculated from the boulder exposure ages range from 0.40 to 0.43 m kyear⁻¹ (maximum rates) and are some of the highest on the Colorado Plateau.     

陕北黄土高原可持续发展评价研究

通过对陕北黄土高原可持续发展评价指标体系和方法的初步研究,设计出了包括 1个高级综合指标——可持续发展综合指数、人口状况等 5个基本指标和人口自然增长率等 30个元素指标的层次性指标体系结构框架,熵技术支持下确定可持续发展指标权重的层次分析法,以及由递阶多层次综合评价、主成份分析和回归分析等数学方法所集成的可持续发展全面综合评价模型,并依次对该地区可持续发展现状及趋势进行了全面分析评价。