面向泛在信息社会的国家战略及图书馆对策研究

在充分理解泛在信息社会内涵的基础上,借鉴国外已有的泛在信息社会国家战略的理论成果和实践经验,结合我国的实际情况、已有基础和可操作性,提出我国泛在信息社会的国家战略初步构想,同时思考图书馆在泛在信息社会环境中的定位和作用,并提出对策,努力推动图书馆在泛在信息环境中的变革。     

动态环境下的高校内部治安防范机制研究分析

近几年,随着我国科技兴国事业的发展,高等教育事业随之获得了一定的发展空间。高等院校的办学规模不断扩大,其自身的教育模式也逐渐从传统的教学模式转为现代化开放式的教育模式。在实际生活中,高校内部治安防范问题,成为社会公众关注的一个重点问题。本文简要分析动态环境下的高校内部治安防范机制方面的内容,旨在更好地促进高校内部治安工作的顺利开展。     

基于ARMA模型的河北省城乡居民信息消费差距分析

利用ARMA模型分析河北省城乡居民信息消费差距。研究结果表明,城乡居民信息消费倾向差距有先增后减的趋势;信息消费系数持续稳定增加,但差距依然存在;信息消费差距逐渐增大,2015年有缩小的趋势。因此应该更加关注农村居民信息消费,进一步提高农村居民收入、加强农村信息基础设施建设、提高农村居民文化水平和消费意识。     

Spatial concentration distribution analysis of cells in electrode-multilayered microchannel by dielectric property measurement

The spatial concentration distribution of cells in a microchannel is measured by combining the dielectric properties of cells with the specific structure of the electrode-multilayered microchannel. The dielectric properties of cells obtained with the impedance spectroscopy method includes the cell permittivity and dielectric relaxation, which corresponds to the cell concentration and structure. The electrode-multilayered microchannel is constructed by 5 cross-sections, and each cross-section contains 5 electrode-layers embedded with 16 micro electrodes. In the experiment, the dielectric properties of cell suspensions with different volume concentrations are measured with different electrode-combinations corresponding to different electric field distributions. The dielectric relaxations of different cell concentrations are compared and discussed with the Maxwell-Wagner dispersion theory, and the relaxation frequencies are analysed by a cell polarization model established based on the Hanai cell model. Moreover, a significant linear relationship with AC frequency dependency between relative permittivity and cell concentration was found, which provides a promising way to on-line estimate cell concentration in microchannel. Finally, cell distribution in 1 cross-section of the microchannel (X and Y directions) was measured with different electrode-combinations using the dielectric properties of cell suspensions, and cell concentration distribution along the microchannel (Z direction) was visualized at flowing state. The present cell spatial sensing study provides a new approach for 3 dimensional non-invasive online cell sensing for biological industry.     

Microwells support high-resolution time-lapse imaging and development of preimplanted mouse embryos

A vital aspect affecting the success rate of in vitro fertilization is the culture environment of the embryo. However, what is not yet comprehensively understood is the affect the biochemical, physical, and genetic requirements have over the dynamic development of human or mouse preimplantation embryos. The conventional microdrop technique often cultures embryos in groups, which limits the investigation of the microenvironment of embryos. We report an open microwell platform, which enables micropipette manipulation and culture of embryos in defined sub-microliter volumes without valves. The fluidic environment of each microwell is secluded from others by layering oil on top, allowing for non-invasive, high-resolution time-lapse microscopy, and data collection from each individual embryo without confounding factors. We have successfully cultured mouse embryos from the two-cell stage to completely hatched blastocysts inside microwells with an 89% success rate (n = 64), which is comparable to the success rate of the contemporary practice. Development timings of mouse embryos that developed into blastocysts are statistically different to those of embryos that failed to form blastocysts (p–value < 10⁻¹⁰, two-tailed Student''s t-test) and are robust indicators of the competence of the embryo to form a blastocyst in vitro with 94% sensitivity and 100% specificity. Embryos at the cleavage- or blastocyst-stage following the normal development timings were selected and transferred to the uteri of surrogate female mice. Fifteen of twenty-two (68%) blastocysts and four of ten (40%) embryos successfully developed into normal baby mice following embryo transfer. This microwell platform, which supports the development of preimplanted embryos and is low-cost, easy to fabricate and operate, we believe, opens opportunities for a wide range of applications in reproductive medicine and cell biology.     

Indoor air quality risk assessment on the Canadian campus by a multilevel integrated weighted average method

Increasing incidents of indoor air quality (IAQ) related complaints lead us to the fact that IAQ has become a significant occupational health and environmental issue. However, how to effectively evaluate IAQ under different scale of multiple indicators is still a challenge. The traditional single-indicator method is subjected to uncertainties in assessing IAQ due to different subjectivity on good or bad quality and scalar differences of data set. In this study, a multilevel integrated weighted average IAQ method including initial walking through assessment (IWA) and two-layers weighted average method are developed and applied to evaluate IAQ of the laboratory building at the University of Regina in Canada. Some important chemical parameters related to IAQ in terms of volatile organic compounds (VOCs), methanol (HCHO), carbon dioxide (CO2), and carbon monoxide (CO) are evaluated based on 5 months continuous monitoring data. The new integrated assessment result can not only indicates the risk of an individual parameter, but also able to quantify the overall IAQ risk on the sampling site. Finally, some recommendations based on the result are proposed to address sustainable IAQ practices in the sampling area.     

基于OPNET的局域网仿真实验设计

OPNET提供了虚拟的网络环境,通过它对网络进行建模,用户可以更加有效地分析网络的性能,确定相关解决方案.本文将OPNET应用于局域网研究,设计局域网仿真实验,通过建立以Hub和Switch为中心节点的局域网,直观地了解不同中心节点对局域网性能的影响,同时也表明了OPNET的良好应用前景.     

从传统天下观到现代国土观念的转型——以民国时期边疆地理著述为中心的考察

传统天下观中的"中国"是一个文化概念,并非现代意义上的国家实体。随着民国建立,中国的国家属性从传统帝国转型成为现代民族国家。然而观念的转变相对滞后,内地人视边疆为化外之地的观念根深蒂固。在当时学者的边疆地理研究著述推动下,传统天下观逐步向现代国土观念转型。民国建立之初,边疆领土问题尚未得到知识界和民众的高度关注,一些学者通过自己对边疆地理的研究试图转变内地人对边疆的淡漠态度。九一八事变后,在外患刺激下知识界形成了研究边疆问题的热潮,涌现出大量边疆地理研究成果,一些学者有意识地就如何建构现代国土观念展开探讨,通过构建国族观念切入国土观念,以民族情感的共鸣唤起国家认同和国土意识,形成了具有时代特征的边疆理论体系。现代国土观念在抗战前后终于得以确立。     

顶级科技期刊封面可视化及典型案例研究

可视化是将对象内容转化为视觉表征符号的一种手段,有利于内容的被理解、传播和再创造.本文探讨顶级科技期刊封面在实践中对可视化方法和技术的应用及发展,以典型封面案例作为研究对象,分析多视角下科技期刊封面创作的内容建构要求、手段、思路与被选择的影响因素,以期提高我国科技期刊对封面设计的重视度和创造力,提升可视化在科学传播中的影响和效用.     

谷歌数字图书馆著作权合理使用问题研究

2004年,美国谷歌公司拟构建数字图书馆,引起了法律争议。谷歌数字图书馆争议的关键在于,谷歌将他人图书扫描进谷歌图书馆,并且在线提供这些图书的目录、索引等信息的行为是否构成著作权合理使用。根据案件的判决结果和理由可知,谷歌的行为具备高度的转化性,对社会公共利益贡献巨大,不会损害著作权人的市场销售,适宜被认定为合理使用。因而,我国著作权法有必要在合理使用条款中明确规定图书馆、搜索引擎公司等为构建数字图书馆或数据库,为公众提供搜索服务而全文扫描他人作品的行为构成合理使用,以为中国的图书馆和搜索引擎公司建立数字图书馆扫清障碍。