武汉市城郊农业的经济分析

根据我国大城市城郊农业的一般经济特征，分析了武汉市城郊农业的功能，特征及其发展的支撑条件和制约因素，并针对其未来发展提出了若干对策。     

基于空间句法和网络分析的武汉市城郊休闲农业点空间可达性研究

休闲农业是乡村旅游发展的重要载体，其可达性水平直接影响着乡村旅游的可持续发展.基于此，论文以武汉市城郊368个休闲农业点作为研究对象，在空间句法方法的基础上，借助网络分析方法，构建空间句法模型和空间关联性网络模型，从全局通达性、局部关联性两个方面对武汉市城郊休闲农业点的空间可达性进行研究，以揭示武汉市城郊休闲农业点的布局特征与空间关联性.结果发现： 1) 武汉市城郊休闲农业点整体密度核心分布较为分散，空间呈现群聚式非均匀分布在武汉市绕城高速周边，形成了绕城高速休闲农业点分布带； 2) 从路网全局通达性来看，武汉市城郊休闲农业点多分布在2级可达性道路300 m缓冲区范围内，且此道路等级缓冲区范围内的农庄经济型休闲农业点可进入性较好，对外通达性一般； 3) 从路网局部关联性来看，区域间休闲农业点内部联系“西密东疏”，东西湖区与黄陂区、蔡甸区休闲农业点联系较为密切；区域内休闲农业点内部关联性差异明显，高速公路、国道沿线区域的休闲农业点关联性普遍较强.     

平顶山市城郊农业发展初探

通过对平顶山市城郊农业现状的分析，针对目前存在的主要问题，提出了发挥区位扰势，控制人口增长，合理利用土地资源，调整农业生产结构，实现城郊农业可持续发展的有效措施和途径     

兰州市生态环境及其调控研究

对兰州市生态环境问题及其形成发展原因进行了综合分析研究，探讨了调控方针策略，进而提出了调整产业结构与布局，全面治理污染，调整大农业结构，发展优质高效的城郊集约型农业，依法管理和保护生态环境，促进区域可持续发展，确保生态环境良性循环的具体实施．     

韶关市城郊农业可持续发展对策探讨

城郊农业具有四大优势和四大功能,不仅有利于实现农业产业化、生态化和现代化,还有利于城市经济建设和市民生活质量的保障。韶关城郊农业发展虽存在一些问题,但可通过强化政策与资金保障、坚持统筹规划、加强城郊生态建设、提高农民科技水平、发展“绿色食品”工程等措施,而增强韶关城郊农业的可持续发展能力。     

城郊休闲农业游客重游行为影响因素的实证研究——以合肥市城郊休闲农业为例

重游率是城郊休闲农业的生命线,研究影响城郊休闲农业游客重游行为的动因和因素是提高重游率、健康发展观光休闲农业的重要途径。通过对合肥市城郊休闲农业游客进行调查访问,运用SPSS 17.0软件对调查结果进行统计分析,结果表明,游客偏好、休闲农业产品固有质量、休闲农业接待条件以及旅游环境存在的替代点是影响城郊休闲农业重游行为的主要因素和内在动力,并在此基础上提出提高游客重游率的建议。     

郑州市城郊农业旅游开发探析

城郊农业旅游拓展了旅游资源的开发形式,促进当地经济发展,针对郑州市城郊农业旅游具有得天独厚的区位、资源和市场优势。本文针对郑州市城郊农业旅游存在的问题,提出了一系列开发对策。     

秦皇岛市城郊农业产业化的探讨

结合秦皇岛市城郊农业产业化的实践,探讨了城郊农业产业化的基本思路,提出了在城郊农业产业化运作中要解决的３个问题,即跳出城郊抓基地,围绕产业化抓服务,围绕销售抓市场。     

城市中大气环境质量的某些影响因素研究

本文采用多对多双重逐步回归分析方法和数量化理论对浙江省某大城市大气中ＳＯ２、ＮＯｘ、总悬浮颗粒（ＴＳＰ）的含量随城市五大功能区和四季变化进行了计算和分析．结果表明城郊大气质量明显好于城区，但城区大气污物含量各区基本一致．大气质量变化受季节影响显著．其污染程度由重到经依次排列为：冬季＞秋季＞春季＞夏季．     

立足城郊区位优势 搞好农业结构调整——对榆次区种植业结构调整的调查

近年来，榆次区立足城郊区位优势，走出了一条具有城郊特色的种植业结构调整新路子。该区农技部门的推广重点实现了3个转型，立足资源优势推出了优势产业。拓宽了农业产品销售渠道，但仍存在订单农业不规范及优质不能优价等问题。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Editorial note for the special topic on ＂Nanopore Analysis＂

The concept of nanopore analysis, using the pore-forming protein a-hemolysin to detect individual nucleic acids at a single-molecule level, was first proposed in 1996. Over the past two decades, tremendous progress has been made in the nanopore field, and nanopore analysis has become a label-free and high-throughput method for probing bio- molecules and other analytes with single-molecule sensi- tivity, especially holds the promising for ＂third generation＂ DNA sequencing. However, challenges still remain in the experimental strategies and the design of whole nanopore-based instruments. Here, we proudly present a special topic dedicated to the topic of ＂Nanopore Analysis＂, with 8 reviews/articles providing up to date coverage of the experimental strategies, theoretical calcu- lations and simulations, and instrument design. Reviews and articles on the experimental strategies cover control of DNA partitioning into a nanopore, detection of target DNA, and the advantages of nanopore-based DNA sequencing. The theoretical calculations and simulations discuss the translocation behavior of DNA, and an inte- grated measurement system and data analysis software are presented for instrument design.     

Effects of climate change on biodiversity

1 Rise of studies on climate change＇s effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America＇s annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].     

Discussing the Expansive Learning in Modern Organizations

<正>1 Introduction Endeavours on learning methods have long occupied the mind spaces of scholars and there have been theories abound on how people learn and in what way organisations can use some of the knowledge gained in the art of learning to maximise human productivity.While the theories by themselves are not solutions to problems,they are steps of inquiry that provide us with interesting perspectives that we can use to extend our knowledge of the dimensions of learning.This paper is an exploratory work on the theories postulated by three notable scholars including Zimmerman