The domestic divide: Access to the Internet in New Zealand

We use unit records of the 2006 census to show that access to the Internet in the home varies geographically in New Zealand primarily as a result of demographic and socio‐economic differences among individuals. Of particular significance is the much lower rates of domestic access experienced by Māori and Pacific Island individuals even after controlling for differences in their age, gender, education, income, occupation and settlement type. While differences in Internet access by ethnicity has been noted before, it is the magnitude and persistence of this difference in New Zealand after controlling for correlated factors that renders this study unique. Our results have important implications in an education environment increasingly reliant on Web access, but they also raise questions about the extent of access to the Internet outside the home.     

加拿大海王星:科学、运行、管理

加拿大海王星是世界最大的海底缆接科学观测网,于2009年开始运行.它连接了位于不同水深和不同海洋地质环境的大批观测仪器,把数据连续不断地通过互联网传给科学家和大众.海王星的建立是为了推动地震过程和大地构造、海底地下流体、海洋生物与气候变化、深海生态系统、工程和信息科学等五大科学命题的研究.为最大程度地推动国际合作,加速科学发展步伐,它的系统使用完全开放,数据全部免费公开,这在科学史上前所未见.这种全方位、全开放的复杂庞大的科研系统需要高超的管理方法和优良的学术环境.     

中国对虾(Penaeus chinensis)幼体血液循环的活体观察

溞对中国对虾早期幼体的循环系统及血液流向进行了活体观察 ,描述了中国对虾早期幼体发育阶段中幼体循环系统血管的走向与分布、血液的流向及循环路径等 ,比较各期幼体循环系统的形态 ,并探讨对虾早期幼体循环系统的发育过程。     

浅谈我国导航电子地图生产企业市场准入制度

分析了国外导航电子地图市场的发展概况和管理机制,以及我国导航电子地图市场的发展现状和存在的问题,在此基础上,进一步论述我国导航电子地图行业实行市场准人制度的必要性.     

PPGIS approach for defining multimodal travel thresholds: Accessibility of popular recreation environments by the water

It is essential to ensure equal accessibility to services, such as sport and recreation facilities or green and water environments. Differences in accessibility can potentially cause negative health and social welfare implications. Accessibility and service area analyses from the perspective of access equality are typically rather simple. They are often based on arbitrary travel-distance thresholds and made only with a single mode of transport in mind. Thus, they exclude the multidimensional nature of accessibility where individuals' travel behavior and perceived accessibility also play an important role. In this paper, a PPGIS method was used to empirically investigate distances and durations that respondents travel with different modes of transport to access popular water environments. Service area analyses were built on person-based and objectively measured threshold values that not only take into account the spatio-temporal elements of transport networks and a land use component but also recognize the requirements and preferences of individuals and their capacity to access and participate. The results showed that the most common mode of transport to access waters is walking. Generally, the residents travel by foot for 1.7 km to access water environments. Cars were found as the second most common mode of transport used, and most of the popular water environments are accessible by car from every corner of the study area in a given travel threshold time. The results demonstrate the importance of deriving local parameters and the potential of the PPGIS approach for accessibility and service area delineation.     

Food Diaries to Measure Food Access: A Case Study from Rural Cuba

This article aims to make a contribution to current debates in the literature on food access by describing a mixed-methods approach to study the access to food in one rural community in Cuba. Each of the forty households in our study was asked to complete a detailed food diary in which they indicated what they ate and where they acquired each of the ingredients that they used for a full week. Although in Cuba the state plays a central role in organizing the distribution of food items, this method revealed a much more complex web of rural food access. By addressing alternative networks of food access and informal social relations, we aim to show how the use of food diaries, in combination with qualitative data from interviews and participant observation, can provide detailed insights in the complex processes and networks of food access.     

The Effects of Spatial Scale and Aggregation on Food Access Assessment: A Case Study of Tucson,Arizona

Adequate access to healthy food has become a social issue due to the recent Great Recession and heightened levels of unemployment. Geographers have focused their attention on how to accurately evaluate food access and how to identify and delineate food deserts; that is, low-income neighborhoods where affordable and healthy food is lacking or limited. Findings of recent food access studies are, however, dramatically inconsistent. We argue that spatial scale and the level of aggregation used in constructing food access measures could account for a major portion of the varying results. We draw on an empirical study in the Tucson, Arizona, metropolitan area, to examine how varying geographic scales and aggregation methods affect food access assessment. We also provide an analysis to show how spatial scale and aggregation practices lead to inconsistent conclusions about food access and designation of food deserts.     

一种工业计算机局部网络通信协议

介绍了一种用于工业现场的计算机局部网络通信协议．详细介绍了网络的硬件结构和与之相配合的软件设计．同时，对其中关键技术如介质存取控制方式，数据的ＤＭＡ存取，缓冲区的分配与管理等作了重点说明．     

Measuring Individuals' Spatial Access to Healthy Foods by Incorporating Mobility,Time, and Mode: Activity Space Measures

Spatial access to healthy foods has drawn growing attention regarding the relationship with people's health conditions and demographic and socioeconomic characteristics. Individuals' differences and the impact of travel behaviors on food accessibility, however, are rarely studied. This study incorporates mobility, time, and transportation mode components to measure each individual's access to healthy foods. We employed three activity space measures to estimate food accessibility: route network buffer, time-weighted standard deviational ellipse (SDE), and mode-weighted SDE. Food accessibility in three activity spaces shows similar variabilities. Geographic size and spatial access to healthy foods differ significantly by income and employment for all three activity space measures. People with higher incomes and those who are currently employed are likely to have larger activity spaces and higher food accessibility. As age increases, people tend to increase their size of activity spaces (in both SDE measures) and food accessibility significantly. Females are likely to have smaller activity spaces and less accessibility to healthy foods (only in the time-weighted SDE measure). Geographic size and spatial access do not differ significantly by education and number of vehicles per household. Although three activity spaces are highly correlated in both geographic size and spatial access, differences still exist among them.