期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
十五分钟社区生活圈典型划定方法及其应用--以成都市金牛区为例 被引量:6
1
作者 高伟 陈香琪 陈莎 《住区》 2022年第2期13-19,共7页
十五分钟社区生活圈是评估旧区各项居住区配套情况,落实国家基本公共服务到基层,应对居民新需求的重要手段,其范围划定是生活圈规划研究实践的重点和难点内容。本文从国家标准、地方导则和相关研究三个方面,整理出三种典型的十五分钟社... 十五分钟社区生活圈是评估旧区各项居住区配套情况,落实国家基本公共服务到基层,应对居民新需求的重要手段,其范围划定是生活圈规划研究实践的重点和难点内容。本文从国家标准、地方导则和相关研究三个方面,整理出三种典型的十五分钟社区生活圈划定方法,其一综合考虑人口规模、用地面积和行政边界;其二基于居民日常出行空间单元;其三基于地理环境和居民行为相结合。以成都市中心城区重点改造区域金牛区三环内区域为例,分别应用三种方法,分析其各自特点,最终综合运用三种方法,得出十五分钟社区生活圈划定方案。 展开更多
关键词 居住区规划 公共服务配套 十五分钟社区生活圈 划定方 行政边界 居民出行 金牛区
下载PDF
Comparison of SCS-CN Determination Methodologies in a Heterogeneous Catchment
2
作者 Andrzej WALEGA Boguslaw MICHALEC +1 位作者 Agnieszka CUPAK Magdalena GRZEBINOGA 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1084-1094,共11页
The aim of this study was to assess the runoff amount from a catchment characterized by diverse land uses by using the Soil Conservation Service Curve Number(SCS-CN) method based on Curve Number(CN) defined for domina... The aim of this study was to assess the runoff amount from a catchment characterized by diverse land uses by using the Soil Conservation Service Curve Number(SCS-CN) method based on Curve Number(CN) defined for dominant homogeneous elementary sub-regions.The calculations employed the SCS-CN method,involving the division of the catchment in two homogeneous parts and determining the runoff amount.The obtained results were compared with the results provided by three other CN determination methods,i.e.the Hawkins function,the kinetics equation,and a complementary error function peak.The catchment is located in a mountain dominated by forest land cover.Empirical CN-Precipitation(CN_(emp)-P) data pairs were analyzed using the mentioned methods,and the highest quality score was achieved from model 1.The results suggest that dividing a catchment into two homogeneous areas and determining their separate CN parameters,used later on to calculate the runoff by means of the presented approach,could be an alternative to the standard methods.The described method is relatively easy,and as it does not require an adoption of numerous parameters,and it can be employed for designing hydraulic facilities. 展开更多
关键词 Asymptotic functions Curve Numberparameter Homogenous sub catchment Land cover Lumped model
下载PDF
Iteration Linear Programming Method and Livestock Ration Optimization
3
作者 Zhang Yongying Wang Jihua Wang Suihua Liu Bo Zhang Weifeng 《Feed & Livestock》 2013年第4期26-32,共7页
Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to "wooden bucket theory" of the nutritional balance, each nutrient in the feeding standard has equal impor... Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to "wooden bucket theory" of the nutritional balance, each nutrient in the feeding standard has equal importance. It's unreasonable to use common goal programming to attach different weighted value to different nutritional parameters. This paper introduces an effective algorithm to deal with this kind of problem. When the permitting cost of livestock ration is given, we can design a ration formula with linear program-this is the first round. Then, according to the differences between the permitting cost and the formula cost gained in the first round, adjust the feeding standard and the feeding raw materials, and conduct the second round of linear programming for ration formula. If there is still a very big difference between the formula cost and the permitting cost, the third round will be taken, and so on. In this iteration course the formula cost gradually approaches the permitting cost. It is the key that the feeding standard and feeding raw materials are modified in each round. This method ensured the nutritive equilibrium with the formulation of least-cost ration. This is an especially important method when the primary goal of the optimization tool is to improve economic and nutritive efficiency. 展开更多
关键词 RATION FORMULATION nutrient requirements objective programming linear programming feeding standard raw material nutritive equilibrium
下载PDF
Numerical Solution to Optimal Feedback Control by Dynamic Programming Approach:A Local Approximation Algorithm 被引量:3
4
作者 GUO Bao-Zhu WU Tao-Tao 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第4期782-802,共21页
This paper considers optimal feedback control for a general continuous time finite-dimensional deterministic system with finite horizon cost functional. A practically feasible algorithm to calculate the numerical solu... This paper considers optimal feedback control for a general continuous time finite-dimensional deterministic system with finite horizon cost functional. A practically feasible algorithm to calculate the numerical solution of the optimal feedback control by dynamic programming approach is developed. The highlights of this algorithm are: a) It is based on a convergent constructive algorithm for optimal feedback control law which was proposed by the authors before through an approximation for the viscosity solution of the time-space discretization scheme developed by dynamic programming method; b) The computation complexity is significantly reduced since only values of viscosity solution on some local cones around the optimal trajectory are calculated. Two numerical experiments are presented to illustrate the effectiveness and fastness of the algorithm. 展开更多
关键词 Curse of dimensionality Hamilton-Jacobi-Bellman equation optimal feedback control upwind finite difference viscosity solutions
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部