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生态分级保护是空间规划中重要支 撑性内容,是全面协调生态保护与开发利用 关系,实现各类空间差异化管控,促进区域 可持续发展的重要途径。本文以华蓥山东麓 为例,通过生态功能重要性和生态敏感性评 价,同时结合景观生态安全格局进行分析, 构建生态保护分级指数模型,按保护程度由 高至低将研究区划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ级。其 中,I级保护区为基本生态控制区,实行严格 的生态保护制度;II级保护区为生态缓冲区, 实行生态修复与城乡建设、产业发展负面清 单管理制度;III级保护区为农业生态区,加 强农业生态环境保护,建立健全绿色生态农 业导向机制;IV级保护区主要为城镇村庄生 态区,加强城乡居民点环境保护,推进人居 环境建设。研究结果可为华蓥山东麓生态修 复保护总体规划提供借鉴,对华蓥山自然保 护区与城镇建设区之间生态过渡地带的精细 化、精准化、差别化管理具有重要意义。  相似文献   
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The difference between the actual and predicted energy consumption for heating in housing is thought to be partly attributable to the use of HVAC systems. More reliable data on energy consumption could help in determining the actual energy performance of dwellings and in the search for the most adequate design for housing and home amenities. Further reductions on energy consumption might also be achieved if energy-saving policy programmes were geared to different household groups. The aim of this paper is to statistically determine Behavioural Patterns associated with the energy spent on heating and to identify household and building characteristics that could contribute to the development of energy-User Profiles. This study had two outcomes: it identified Behavioural Patterns to be used in energy calculations and it discerned User Profiles with different behaviours. Five underlying groups of behavioural variables were found, which were used to define the Behavioural Patterns and User Profiles. The groups showed statistically significant differences in the scores for most of the behavioural factors. This study established clear relationships between occupant behaviour and household characteristics. However, it seems difficult to establish relationships between energy consumption and Behavioural Patterns and household groups.  相似文献   
24.
Thin polymer films are deposited on nonplanar geometries via initiated chemical vapor deposition (iCVD). Films in microtrenches exhibit step coverage of 0.85 for the highest aspect ratio trench studied here. An analytical model shows that the sticking probability of the initiating radical is a function of monomer surface concentration and takes values between 1.1 × 10− 2 and 5.0 × 10− 2 for the conditions studied here. These results indicate that iCVD proceeds via reaction of a vapor phase initiating radical with a surface adsorbed monomer. The high degree of conformality allows iCVD to be used to create patterns with features less than 10 µm by physically masking the substrate.  相似文献   
25.
This paper presents a controlled experiment, conducted at the University of Kaiserslautern which evaluates an approach known as SORT, for the systematic refinement and translation of UML Diagrams. Specifically, the experiment investigates the effects of SORT, with respect to the mapping of object-oriented UML design models to source code, by comparing the effects of different approaches to such mappings (SORT and ad-hoc1) on the quality attributes understandability, verifiability, and effort (time). The experimental results demonstrate that OO systems developed by applying SORT are more understandable and verifiable. In summary, SORT can help to improve the quality of software systems, but its application alone does not guarantee quality. Editor: Murray Wood 1The mapping strategy followed by most mainstream methods is based on personal experience and general mapping guidelines. Thus, mappings are performed on an individual basis without systematic guidance (i.e., these approaches can be characterized as “ad-hoc” mapping approaches).  相似文献   
26.
While it has been suggested that patterning activities support early algebra learning, it is widely acknowledged that the shift from perceiving patterns to understanding algebraic functions—and correspondingly, from reporting empirical patterns to providing explanations—is difficult. This paper reports on the collaborations of grade 4 students (n = 68) from three classrooms in diverse urban settings, connected through a knowledge-building environment (Knowledge Forum), when solving mathematical generalizing problems as part of an early algebra research project. The purpose of this study was to investigate the underlying principles of idea improvement and epistemic agency and the potential of knowledge building—as supported by Knowledge Forum—to support student work. Our analyses of student-generated collaborative workspaces revealed that students were able to find multiple rules for challenging problems and revise their own conjectures regarding those rules. Furthermore, the discourse was sustained over 8 weeks and students were able to find similarities across problem types without the support of teachers or researchers, suggesting that these grade-4 students had developed a disposition for evidence use and justification that eludes much older students.  相似文献   
27.
会话外观是一种经典的EJB设计模式,其实现通常都是静态的,亦即要将EntityBean的LocalHome接口硬编码为会话外观SessionBean具体的实例变量,这在需要封装多个EntityBean时,会话外观SessionBean将变得异常复杂而难以实现和维护。本文通过对以上静态会话外观模式不足的分析,提出了一种基于Java反射机制和接口技术的、动态会话外观模式的实现策略,有效的解决了由单一会话外观来封装多个EntityBean的问题。  相似文献   
28.
一个好的软件设计框架能有效的理清系统结构,降低系统复杂度。基于MVC模式的Struts框架,对复杂的Web应用系统开发是较为理想的系统构建方式。文章结合笔者开发大型国资管理系统的实践,介绍Struts框架的体系结构以及基本设计思想,同时给出一个用户登陆实例,介绍了如何利用Struts技术开发基于MVC的Web应用。进一步揭示了Struts是一个高度可配置、高度扩展性的框架,并特别指出Struts框架在开放大型Web应用方面发挥的优势。  相似文献   
29.
中国传统服饰是礼的重要载体 ,是礼制的表现形式 ,在款式、色彩和纹样上追求精神寓意和象征意义  相似文献   
30.
An integrated methodology for successful development and implementation of enterprise information systems is developed. This paper describes the methodology and defines five components and one repository which can be customized with business scenarios and patterns according to various business environments. Five components consist of information strategy planning, economic justification and measurement, enterprise information system appraisal, package software evaluation, and unified modeling tools. They characterize the methodology through its entire road map. Also, case studies are provided to prove its practical values.  相似文献   
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