基于多源数据的自然生态空间分类体系构建及其识别

研究目的:探讨市县尺度下自然生态空间分类体系和多源数据下自然生态空间识别方法。研究方法:采用归纳比较法构建自然生态空间分类体系,通过综合分析法建立多分类体系转换机制,运用GIS空间分析法识别自然生态空间。研究结果:(1)市县级自然生态空间是指生产性空间和承载性空间以外,以发挥土地生态系统服务功能为主导,以提供生态产品为主,对维护区域生态系统稳定性,保障区域生态安全格局具有重要作用的用地空间;(2)自然生态空间可分为基础生态空间和人工生态空间两个一级类,10个二级类,26个三级类;(3)2015年鹤壁市自然生态空间总量606.08 km~2,其中基础生态空间554.41 km~2,人工生态空间51.67 km~2。研究结论:依据市县尺度自然生态空间分类体系,运用多源数据融合转换识别方法能快速准确识别自然生态空间数量和空间分布。     

Robust Markowitz mean‐variance portfolio selection under ambiguous covariance matrix

This paper studies a robust continuous‐time Markowitz portfolio selection problem where the model uncertainty affects the covariance matrix of multiple risky assets. This problem is formulated into a min–max mean‐variance problem over a set of nondominated probability measures that is solved by a McKean–Vlasov dynamic programming approach, which allows us to characterize the solution in terms of a Bellman–Isaacs equation in the Wasserstein space of probability measures. We provide explicit solutions for the optimal robust portfolio strategies and illustrate our results in the case of uncertain volatilities and ambiguous correlation between two risky assets. We then derive the robust efficient frontier in closed form, and obtain a lower bound for the Sharpe ratio of any robust efficient portfolio strategy. Finally, we compare the performance of Sharpe ratios for a robust investor and for an investor with a misspecified model.     

从土地资源优势区配置到主体功能区管理：一个国土空间治理的逻辑框架

研究目的:以土地资源配置方式遵从优势区开发原则到服从主体功能区分工协作规则演进规律,解释现行中国治理模式下国土空间管理逻辑。研究方法:文献分析法和理论分析法。研究结果:传统优势区开发理念为早期区域发展带来了集聚与规模经济效益,但其内部仍存在生产、生活、生态空间结构失衡等问题,降低了土地资源空间配置效率。主体功能区战略是传统优势区土地资源空间配置理念转型,是中国特定时期具有国家特色的经济发展模式,关键在于明确地方土地资源空间配置核心定位,应以法律规范"央地"土地关系、差别化实施政策制度安排、引导公众参与规划决策、创新生态(经济)补偿机制。研究结论:不同分区土地资源空间配置关系协调是世界性问题,转型时期中国国土空间优化和规制治理重点在于厘清中央与地方事权关系,精准落地县域主体功能区建设,健全主体功能配套政策体系。     

传统白族民居如何适应现代功能需求——以沙溪白族民居为个案

沙溪的传统白族民居保存较好,数量庞大,既有大理白族民居的特点又有沙溪的地方特征。民居建筑材料为土、木、石。沙溪地区太阳辐射剧烈,冬季严寒,为提升室内舒适度,需要一些现代建筑技术手段来解决这些问题。随着社会的发展,为了适应现代化的生产方式,民居的功能空间发生了改变,并且伴着旅游开发,商业也作为一个不可缺少的因素融入到了沙溪民居中。     

Pareto-undominated and socially-maximal equilibria in non-atomic games

This paper makes the observation that a finite Bayesian game with diffused and disparate private information can be conceived of as a large game with a non-atomic continuum of players. By using this observation as its methodological point of departure, it shows that (i) a Bayes–Nash equilibrium (BNE) exists in a finite Bayesian game with private information if and only if a Nash equilibrium exists in the induced large game, and (ii) both Pareto-undominated and socially-maximal BNE exist in finite Bayesian games with private information. In particular, it shows these results to be a direct consequence of results for a version of a large game re-modeled for situations where different players may have different action sets.     

Theoretical analysis and model design of search for ecological conservation redlines based on the sensitivity assessment of ecosystem services

Most small-scale social economies are characterised by their deficiency, lack, and/or difficulty in matching natural data. Against this backdrop, this paper builds a relatively uniform theoretical framework and designs a more economical and objective method for demarcating ecological conservation redlines (ECR) based on sensitivity assessment of ecosystem services. The results show that the sensitivity assessment model designed in this study can identify sensitive zones effectively, and that the ECR in Hubei Province are well within the sensitive zones so identified. The delimited areas based on the sensitive assessment of ecosystem services have great similarities (95%) with the actual ECR areas in Hubei Province. The most ecologically important functional zones (EIFZ) can also be identified using the regional ecological sensitivity coefficient. When the threshold of EIFZ is set higher, the probability that it falls within the ecologically sensitive areas is greater and the ECR delimited by the method proposed in this study will be more reliable. Theoretically, the delimitation of ECR can be inserted at any evaluation level with a grid resolution higher than that of the land use data, which can be used as a supplement to the ECR delimitation method in ecology or geography.     

价值共创行为分析框架构建 ——基于赋能理论视角

通过文献调查并结合案例的描述性分析,提出数字技术时代价值网络中不同行为主体之间的赋能内涵、关键维度以及基于赋能跨层次效应的价值共创行为分析框架。将"赋能氛围""主体赋能"分别作为价值网络中赋能的宏观维度和微观维度进行概念化。界定了两个维度的关键组成要素,分别包括信息共享、开放性结构、协同规则以及主体关系、资源整合和影响。构建了赋能的跨层次效应模型,分析了赋能的宏观-微观跨层次效应及其对价值网络生态和主体价值创造的影响。     

基于底线预警的国土空间生态修复规划实施监督体系研究

国土空间生态修复是推进生态文明建设的重大举措，构建基于底线预警的国土空间生态修复规划实施监督体系是完善国土空间规划“一张图”信息系统的重要组成部分和政策支撑。通过对生态修复规划实施监督体系建设的研究，把握底线控制与监测预警机制，对接国土空间生态修复业务管理各项需求，搭建“五梯度四体系”的生态修复规划动态监测实施监督信息系统，构建以“七个一”为主要内容的生态修复规划底线预警监测评估机制，并与各层级国土空间规划“一张图”实施监督信息系统进行衔接，实现对生态修复规划实施的动态监测和预警。     

终身学习视角下公共图书馆的转型与发展思考

公共图书馆作为公共文化服务体系的重要组成部分,在构建学习型社会的大背景下,为促进终身学习的理念,借鉴国外图书馆的前沿探索,提升人文素质和知识内涵,实现公共图书馆在新的历史形势下自身的转型与发展。     

ZY5000/15/32掩护式液压支架的优化设计

当支架工作一定时间后出井维护时,需要将前梁与顶梁之间的销轴拿掉后改为运输销轴连接,由于井底空间、设备有限,操作极为不便;另外,由于前梁千斤顶是靠销轴受力,因为支架工作时间比较长且井下环境恶劣,导致销轴出现变形、生锈等现象,以致销轴不易拆卸。