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1.
道教洞天福地作为中国名山风景的经典类型之一,在宗教山岳景观中占据独特地位。浙东天台山水神秀,历代高道以入山隐修为主要目的,形成了道教在区域山林的景观文化基础。从天台山“神仙之乡”的文化背景出发,从“想象与实践”的视角切入,梳理了天台山洞天福地的景观流变:分析其“不死之福庭”地域性景观的形成经历了“赤城→桐柏”的信仰转移过程;以天台山为坐标,洞天福地格局打破了区域“层级”分布特征,而呈现大范围“州郡”空间格局。作为“联结点”的天台山,洞天世界沟通了宇宙、山、人3个基本场域,由此衍生出“洞宫”式和“周回”式山岳空间营建典范。旨在挖掘洞天福地中典型案例的价值,为中国洞天福地体系的构建提供理论依据。  相似文献   
2.
As a symbol of sharing economy, ride-hailing services have spread to Asia, where various forms of services have been established according to the existing socio-technical regimes, including legal, policy, and environmental concerns. China, in particular, has accepted ride-hailing services by revising existing institutions. This study analyzes China’s acceptance of ride-hailing services in the socio-technical system context set up for legacy services. Simulation modeling, combined with transition theory and an agent-based model, is used to analyze the data. This study calculates consumer disutility based on mobility market share, reflecting consumer preference, and predicts the sustainability of ride-hailing services. The simulation results conclude that legalization and socio-technical context are of importance for sustainable mobility.  相似文献   
3.
Transportation demand of shipping container fluctuates due to the seasonality of international trade, thus, every 3–6 months, the liner company has to alter its current liner shipping service network, redeploy ships and design cargo routes with the objective of minimizing the total cost. To solve the problem, the paper presents a mixed integer linear program model. The proposed model incorporates several relevant constraints, such as weekly frequency, the transshipment of cargo between two or more service routes, and transport time. Extensive numerical experiments based on realistic date of Asia–Europe–Oceania shipping operations show that the proposed model can solve real-case problems efficiently by CPLEX. The results demonstrate that the model can reduce ship’s capacity consumption and raise ships’ capacity utilization.  相似文献   
4.
带关键字搜索的公钥加密(PEKS)是一种有用的加密原语,它允许用户将在加密数据上搜索的功能委托给不可信的第三方服务器,而不影响原始数据的安全性和隐私性。但是,由于缺乏对于数据的加密以及解密能力,PEKS方案不能单独进行使用,必须与标准的公钥加密方案(PKE)相结合。因此,Baek等人在2006年引入了一种新的加密原语,称为结合PKE和PEKS的加密方案(PKE+PEKS),它同时提供了PKE和PEKS的功能。目前,已有文献提出了几种PKE+PEKS方案。然而,他们都没有考虑关键字猜测攻击的问题。本文提出一个新的高效且能够抵抗关键字猜测攻击的PKE+PEKS方案,与已有方案相比,该方案在性能上有很大的提升,并且在生成关键字和数据密文时,不需要使用双线性对,极大地降低了计算和存储成本。安全性分析表明,本文中所提出的方案能够满足密文隐私安全性、陷门不可区分性和抗关键字猜测攻击的安全性。效率分析表明,本分提出的方案更加高效。  相似文献   
5.
苏州平江市民文化活动中心是一个以会议、报告和放映电影为主,兼有文艺表演的多功能剧场.声学设计既要考虑到会议、报告所需要的语言清晰度问题,又要考虑到文艺演出所需要的音乐丰满度问题.利用odeon声学设计分析软件对该市民文化活动中心的声学问题进行了模拟分析.对建成后的市民文化活动中心进行的测量表明声学设计取得了满意的效果.  相似文献   
6.
Few jurisdictions have translated internationally agreed social impact assessment (SIA) principles into statutory provisions. Governments and regulatory bodies tend to provide developers with high-level frameworks, or require that social impacts be ‘considered’, without specifying how this is to be done. In Australia, this lack of clarity leaves all parties uncertain about requirements for SIA. The New South Wales (NSW) Government’s 2017 release of the SIA guideline for State-significant mining, petroleum and extractive industry development represents an attempt to clarify requirements and provide guidance. In this paper, we describe the process of bringing this guideline to fruition from the perspective of being directly involved in its development, and highlight the challenges involved in integrating leading-practice principles into the state’s pre-existing policy framework. While the guideline represents a significant advance in policy-based SIA guidance, some aspects leave room for improvement. The real test of the guideline’s impact will lie in its influence on SIA practice in NSW, and ultimately in social outcomes for communities affected by resources projects.  相似文献   
7.
Combinatorial auction is a useful trade manner for transportation service procurements in e-marketplaces. To enhance the competition of combinatorial auction, a novel auction mechanism of two-round bidding with bundling optimization is proposed. As the recommended the auction mechanism, the shipper/auctioneer integrates the objects into several bundles based on the bidding results of first round auction. Then, carriers/bidders bid for the object bundles in second round. The bundling optimization is described as a multi-objective model with two criteria on price complementation and combination consistency. A Quantum Evolutionary Algorithm (QEA) with β-based rotation gate and the encoding scheme based on non-zero elements in complementary coefficient matrix is developed for the model solution. Comparing with a Contrast Genetic Algorithm, QEA can achieve better computational performances for small and middle size problems.  相似文献   
8.
9.
Considering autonomous mobile robots with a variety of specific functions as a kind of service, when there are many types and quantities of services and the density of regional services is large, proposing an algorithm of Circular Area Search (CAS) because of the problem of multi-robot service scheduling in various areas. Firstly, Django is used as the web framework to build the Service-Oriented Architecture (SOA) multi-robot service cloud platform, which is the basic platform for multi-service combination. Then, the service type, the latitude and longitude and the scoring parameters of the service are selected as the service search metrics to design the CAS algorithm that based on the existing service information registered in MySQL and the Gaode Map for screening optimal service, and then providing the service applicant with the best service. Finally, the service applicant applies for the self-driving tour service as an example to perform performance simulation test on the proposed CAS algorithm. The results show that the CAS algorithm of the multi-robot service cloud platform proposed in this paper is practical compared to the global search. And compared with the Greedy Algorithm experiment, the service search time is reduced about 58% compared with the Greedy Algorithm, which verifies the efficiency of CAS algorithm.  相似文献   
10.
Currently, ethnic and racial minority individuals represent a large proportion of the U.S. population, and researchers expect that they will represent the majority of the population by 2050. This shift in U.S. demographics calls for a greater awareness and integration of cultural issues into the assessment and treatment of ethnically and linguistically diverse clients. This article examines the unique beliefs and manifestations of illnesses among Haitians in connection with the American Psychological Association's (APA, 2002) Multicultural Guidelines. The authors use a common culture-bound syndrome, Séizisman, to illustrate the cultural beliefs, assessment, and treatment of illnesses among Haitians. In so doing, they demonstrate how to incorporate the APA Multicultural Guidelines into treatment with clients of diverse cultural and racial backgrounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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