浅议中国城市化的特征和挑战

指出城市化是我国当前社会经济发展的重要议题,在经济全球化的背景下,分析全球城市化的现状,西方发达国家的城市化演变过程,探讨我国城市化的特征和面临的挑战,探索集约化、多元化协调发展的可持续发展型城市化模式。     

刍议煤矿信息化建设面临的难题及挑战

煤矿信息化建设是煤矿企业现代化发展的必经之路,如何加快信息化建设,通过信息技术增强企业的核心竞争力是煤炭企业发展急需解决的问题。该文主要阐述煤炭信息化建设面临的难题及挑战,并提出了相应的改善对策,希望能为煤炭企业的信息化建设提供一些参考。     

2003年美国总统绿色化学挑战奖

论述了一年一度的美国总统绿色化学挑战奖,对于绿色化学研究、推动化学化工等领域的安全与环保工作有启发和指导意义。2003年获奖的个人和公司已经揭晓,介绍了他们的绿色化学成就——固体氧化物催化剂合成的无废水工艺(更新合成路线奖)、微生物法生产1,3．丙二醇(改进溶剂和反应条件奖)、EcoWorx(tm)地毯片(设计更安全化学品奖)、温和的选择性脂肪酶催化聚合(绿色化学学术奖)、高效而环境友好的生物杀真菌剂Serenade(r)(小企业奖)等,指出与生物技术相结合是未来化学化工的重要方向。     

一种具有防欺骗和挑战应答时限的动态身份认证技术

文章简要回顾了身份认证技术的发展历程和目前应用的动态身份认证技术原理,介绍了一种具有防欺骗和挑战应答时限的动态认证技术,以及此技术在现有技术上的改进和发展。该技术安全、可靠、简便易行,可以拒绝第三方的重放攻击,有效地防止了第三方对口令的猜测和穷举攻击,广泛应用于电子政务、网上银行、网上营销等各领域。     

Effects of replacing inorganic salts of trace minerals with organic trace minerals in the diet of prepartum cows on quality of colostrum and immunity of newborn calves

Our objectives were to evaluate the impact of supplementary trace mineral (TM) form—inorganic salts (STM; Co, Cu, Mn, Zn sulfates, and Na selenite) or organic (OTM; Co, Cu, Mn, Zn proteinates, and selenized yeast)—in the prepartum diet on quantity and quality of colostrum, passive immunity, antioxidant biomarkers, cytokine responses to lipopolysaccharide (LPS), health, and growth of newborn calves. Pregnant heifers (n = 100) and cows (n = 173) were enrolled at 45 d before calving, blocked by parity and body condition score, and allocated randomly to STM (50 heifers; 86 cows) or OTM (50 heifers; 87 cows) supplementation. Cows in both treatments were fed the same diet, except for the source of supplementary TM. Within 2 h of calving, dams and calves were separated, colostrum was harvested, the yield was measured, and a sample was saved for posterior analyses of colostrum quality. A subgroup of calves (n = 68) had a blood sample collected before colostrum feeding. After colostrum feeding, all samples and data collection were limited to 163 calves (STM = 82; OTM = 81) fed 3 L of good quality (Brix% >22) maternal colostrum via nipple bottle minutes after harvesting. Concentration of IgG in colostrum and serum was determined 24 h after colostrum feeding using radial immunodiffusion. Concentration of TM in colostrum and serum were performed by inductively coupled plasma mass spectrometry. Activity of glutathione peroxidase, ferric reducing ability of plasma, and concentration of superoxide dismutase were evaluated in plasma by colorimetric assays. Ex vivo whole blood stimulation with LPS was performed on d 7 of life to evaluate cytokine responses in a subgroup of 66 calves. Health events were recorded from birth to weaning, and body weight was recorded at birth (all calves) and on d 30 and 60 (heifers only). Continuous variables were analyzed by ANOVA and binary responses were analyzed by logistic regression. Complete replacement of STM by OTM in prepartum diet resulted in greater concentration of Se (461 vs. 543 ± 7 μg/g; ± SEM) but did not alter the concentration or total mass of other TM and IgG in colostrum. Female calves of the OTM group had greater concentration of Se in serum at birth (0.23 vs. 0.37 ± 0.05 μg/mL), were lighter in weight at birth (40.9 vs. 38.8 ± 0.6 kg) and weaning (93.2 vs. 89.7 ± 1.6 kg) than those of the STM group. Maternal treatments did not affect passive immunity or antioxidant biomarkers. On d 7, basal concentrations (log₁₀ of concentration in pg/mL) of IFNγ (0.70 vs. 0.95 ± 0.083) and LPS-stimulated concentrations of CC chemokine ligand 2 (CCL2; 2.45 vs. 2.54 ± 0.026), CC chemokine ligand 3 (CCL3; 2.63 vs. 2.76 ± 0.038), IL-1α (2.32 vs. 2.49 ± 0.054), and IL-1β (3.62 vs. 3.86 ± 0.067) were greater in OTM than in STM. Supplementation with OTM in pregnant heifers, but not in pregnant cows, reduced the incidence of preweaning health problems in their calves (36.4 vs. 11.5%). Complete replacement of STM by OTM in the prepartum diet did not cause major changes in colostrum quality, passive immunity, and antioxidant capacity, but increased cytokine and chemokine responses to LPS on d 7 of life and benefited preweaning health of calves born to primiparous cows.     

Regional science in the Netherlands: A contextual interpretation of the “power of smallness”

This paper provides an overview of regional science research in the Netherlands since the 1960s. It adopts a contextual thematic approach in identifying and interpreting regional science research topics, practices and methodologies, inspired by Toynbee's challenge and response concept. It argues that place-based, cultural and historical conditions in the Netherlands have prompted a pragmatic and evidence-based scientific approach, in which in particular an innovative quantitative orientation accompanied by a methodological heterogeneity has given Dutch regional science a high international profile. Over the past decades, numerous regional scientists in the country have contributed to this achievement, too many to be mentioned in this overview. This paper has its limitations and offers mainly thematic examples of original—often quantitative—research undertaken by various Dutch regional scientists, that make a difference compared to general approaches in Europe and world-wide. From our concise review we conclude that – despite the small size of the country – the challenge and creative response model of Dutch regional science has been rather successful.     

基于短信动态口令的身份认证管理服务

针对配电馈线终端（FTU）智能手机人机交互接口MMI应用身份认证管理的技术要求,需要在配网调控制中心建设动态身份验证的服务器系统,以实现对手机MMI应用的安全防护。控制中心服务器侧的身份认证管理软件采用挑战/响应方式的动态口令身份认证技术,并使用手机短信实现认证信息的传输,微型加密算法TEA对短信内容进行加解密处理,从而实现MMI应用的异步双因子安全体系登录认证的目的。在分析研究相关理论、方法和实现技术的基础上,完成了身份认证管理软件的设计与实现,并在用户控制中心机房成功部署,达到了项目开发的目的。     

浅析信息技术新业态下温州地区发展 数字农业面临的机遇与挑战

Under the new forms of information technology, digital agriculture, as an industry vigorously promoted by the state, is of great significance to the transformation of traditional agriculture and the implementation of National Rural Revitalization Strategy. This paper firstly analyzes the opportunities and challenges of developing digital agriculture in China, especially Wenzhou. On this basis, combined with the advantages of Wenzhou, this paper puts forward the measures and suggestions for the development of digi- tal agriculture in Wenzhou from the aspects of brand construction and marketing of agricultural products, construction of agricultural product supply chain and quality control traceability.     

发展高等职业教育之我见

发展高等职业教育，机遇与挑战并存，我们必须抓住机遇，迎接挑战。针对师资水平低、毕业生就业难，培养目标不到位及高职教育资金来源等问题，采取相应措施，如建立一支强大的教师队伍、与企业合作、更新观念、实行素质教育等，谋求高职教育大发展。     

关于我国风电产业发展的若干思考

风力发电作为一种绿色能源越来越受到世界各国的重视并得到了广泛的开发和利用。近年来,在国家大力发展清洁能源政策的扶持下,我国风电产业以超预期的速度迅猛发展,但与世界上风电发展水平较高的国家相比,我国风电发展相对滞后,产业基础比较薄弱,风电发展仍面临一些挑战。分析了我国风电产业发展过程中出现的主要问题并就如何促进我国风电产业健康发展提出了对策与建议。