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1.
柴达木盆地太阳能资源分布及评估初探 总被引：1，自引：0，他引：1
本文利用1961～2007年格尔木辐射观测站太阳总辐射和日照百分率实测资料,建立了适用于计算柴达木盆地太阳总辐射的经验公式,其相对误差在1.46%～4.99%,利用该公式计算了柴达木盆地无辐射观测地区的太阳总辐射量,进而了解盆地太阳能资源分布状况。结果表明：按照《气候应用手册》划分指标,盆地太阳能资源属Ⅰ级,即太阳能源丰富区,其中盆地西北部太阳能资源极丰富,盆地中部次之,盆地东部稍逊。太阳能总辐射量月变化较大,5月份最大,12月份最小;季节差异明显,春夏季较好,秋冬季较差。 相似文献
2.
杭州太阳日总辐射变化特征分析 总被引：2，自引：0，他引：2
太阳辐射是地球上最基本、最重要的能源来源,也是气候形成和天气变化的主要因子之一,对工农业生产、国防建设有着重要的意义.本文利用太阳总辐射的气候学经验公式Q=O0(a+bs),根据杭州1993年～2005年逐时太阳总辐射和逐日日照百分率的资料,采用SPSS统计软件的回归分析,按季节导出杭州太阳日总辐射经验公式的系数,并对四季经验公式进行检验与误差分析.结果表明:①按季节建立的经验公式的精度较高;②杭州地区月太阳总辐射平均值为359.17MJ/m2,月太阳总辐射在(204.31～564.83)MJ/m2之间;月变化表现为双峰型,5月和7月为两个高值,6月因受梅雨天气的影响为一相对低值;③杭州日总辐射的历年平均值为11.87MJ/m2,上午、下午辐射总量分别7.52MJ/m2和4.35MJ/m2.比例约为1.7:1一天中杭州太阳总辐射最大值在11时36分出现. 相似文献
3.
本文通过太阳总辐射气候学计算公式Q=Q0（a＋bs）,根据玉树站1993～2009年历年各月的总辐射和日照百分率,采用最小二乘法拟合出公式中各月的经验系数,并计算了玉树州各气象站太阳总辐射值。结果表明：玉树地区太阳总辐射年总量大致在6300～6600MJ·m^-2之间,空间分布由西向东逐渐递减。高值区在玉树西部,五道梁年总辐射为6639．5MJ·m^-2,低值区在玉树东部的清水河,年总辐射在6350MJ·m^-2以下,区域平均为6446．5MJ·m^-2。太阳总辐射年变化表现为5月最大,12月最小。近年来随着气候变暖和大气污染的影响,云量和气溶胶增多,从而增强了大气对太阳光的反射及吸收作用,使太阳辐射减小,日照时数下降。玉树地区太阳辐射资源丰富,可利用日数多,可开发条件优越,综合利用太阳能的潜力巨大。 相似文献
4.
东北地区辐射资源栅格化信息化系统的建立 总被引：9，自引：6，他引：9
借助GIS平台和DEM数据，生成东北地区1km×1km经度,纬度,海拔高度，坡度，坡向数据库。利用1960年-1990年累年月平均气候学方法计算了东北地区189个气象台站总辐射、直接辐射、PAR和地表有辐射的月值和年值；并用极轨气象卫星资料处理软件和VB6.0语言处理了1992年辽宁省5月-8月的NOAA AVHRR 数据，得到了辽宁省5月-8月1km×1km网络的地面反射数据。在基础上，分省建立了各种辐射值与宏观地理因子（经度,纬度,海拔高度）的三维二次空间分布模式。半理论半经验地定量分析了坡度向对辐射和par的影响，最终建立了东北地区辐射资源删格化信息化信息系统。 相似文献
5.
郭素英 《内蒙古科技与经济》2000,(2):24-24
发展速度是报告期水平与基期水平之比 ,当基期水平为正值时 ,其计算是不成问题的 ;但当基期水平为负值时 ,这种计算方法就出现了问题。见下表 :某企业利润额资料单位 :万元年份 1990 19911992 1993 1994利润 (亏损 ) 40 10 -110 -2 0 3 0 据上述资料计算该企业利润额的年速度。1 991年比 1 990年 :1 0 /40 =2 5%,利润额减少75%;1 992年比 1 991年 :- 1 1 0 /1 0 =- 1 1倍 ,利润额减少 1 2倍 ;这两项年速度的计算无疑是正确的。但如果 1 993年、1 994年的年速度仍照此计算 ,就会得出错误的结论—— 1 993年比 1 992年 :- 2 0 /-1 1 0 =1 8… 相似文献
6.
广东省太阳总辐射的气候学计算及其分布特征 总被引：37，自引：1，他引：37
通过对国内外太阳总辐射气候学计算方法的分析对比，确定 为广东省最佳计算公式。根据广州、汕头1961--2002年历年各月的总辐射和日照百分率，采用最小二乘法拟合出公式中各月的经验系数，并计算了全省各地的月太阳总辐射。结果表明，除雷州半岛的徐闻和雷州以外，全省其他地区太阳总辐射年变化都表现为单峰型，7月最大，2月最小，而雷州半岛的徐闻和雷州表现为双峰型，7月和5月为两个高值，6月为一相对低值。全省年太阳总辐射在3,758.8--5,273 MJ?m-2之间，东部、沿海多，北部、西部少，其中年总辐射最大值出现在粤东的南澳，其值高达5,273 MJ?m-2，最低值出现在粤北的连山，年太阳总辐射只有3,758.8 MJ?m-2 相似文献
7.
黄土高原地区降水资源特征及其对植被分布的可能影响 总被引：14，自引：2，他引：14
选取了黄土高原 4 1个站点 1 96 1年～ 1 990年的月降水资料 ,计算并分析了黄土高原地区多年平均年降水量、年内各个季节的降水分配比例、年降水变率和离差系数等分布特征 ,同时对黄土高原不同地区光热水资源的耦合特征和土壤水分在雨季恢复的程度进行了分析。结果表明 :森林地带分布在黄土高原东南部和立地条件好的山地 ;荒漠草原带分布在水热资源缺乏的西北部 ;森林草原过渡带和典型草原带分布在森林带和荒漠草原带之间 ,是黄土高原地区的主要植被地带。最后 ,给出了林草适宜分布区域及其受限区域 ,可为当前黄土高原植被生态恢复与建设提供参考 相似文献
8.
利用风云系列静止气象卫星可见光通道的行星反照率和红外通道亮温,依据地球-大气系统的物理模式反演得到三江源地区太阳总辐射。本文在Dedieu模式的基础上,考虑了高程、气溶胶、云和水汽的变化对晴天地表太阳辐射的影响,同时结合2005年-2007年玉树、玛沁两站地面实测辐射资料对模型参数修正,反演得到了地面的太阳总辐射;反演数据与地面辐射站直接测量的结果进行了比较分析,小时、日辐射相关系数达0.92以上,晴天两者的差别在5%以内,绝对误差在2MJ/m2以内。小时太阳总辐射时间尺度上开口向下抛物线,最大值在中午13时左右,最小值出现19时;日太阳辐射波动变化,日最大值约为42.50MJ/m2,最小值为1.38MJ/m2;在对计算地表太阳总辐射的经验公式进行时间推广时,根据梯形积分的思想,计算日太阳总辐射,反演值与实测值一致性较高。从月太阳总辐射空间分布图分析,年内选择辐射最大月份7月份分析,三江源地区7月份太阳总辐射在(500～800)MJ/m2之间,并呈从西到东减少趋势,最大值分布主要集中在可可西里地区,最小值集中在东南部地区。研究该区域太阳能其分布特征不仅可以拓展清洁能源的利用,而且有利于三江源地区植被生态环境保护。 相似文献
9.
复杂地形条件下的太阳资源辐射计算方法研究 总被引：24，自引：8，他引：24
借鉴国内外已有的太阳辐射计算方法，考虑地形和大气衰减因子，通过组件技术实现GIS与太阳总辐射计算模型集成，建立了太阳潜在总辐射计算模型。同时利用我国107个气象观测站的多年逐日太阳辐射资料，假设多年中有1d为晴朗无云的天气，即取多年中的最大太阳总辐射值为核算日的潜在日总辐射值，进行模型检验，证明该方法可行。 相似文献
10.
为填补实测太阳辐射资料的空缺,利用南京地区1961年-2010年常规气象资料建立了由总云量反演逐日太阳辐射的模型,并对南京地区近50年来太阳总辐射的变化特征进行了分析.首先采用南京气象站1961年-2000年实测太阳总辐射数据借助粒子群优化算法确定了模型参数,然后利用2001年-2010年数据对模型效果进行了检验.结果表明:辐射模型模拟值与实测值拟合程度较好,Nash-Sutcliffe效率系数(NSE)、均方根误差(RMSE)和皮尔逊相关系数(r)分别为0.74、48.6W/m2和0.8.南京地区太阳总辐射受云量影响较大,其年内变化趋势基本与晴空辐射相吻合,但又存在差异,这主要是与梅雨季节有关. 相似文献
11.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
12.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
13.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
15.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
16.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
17.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献
18.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
19.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
20.
Leah A. Lievrouw 《The Information Society》1998,14(2):83-96
The main premise of this article is that in information societies generally, and in virtual social contexts particularly, a distinctive style of interaction to facilitate the communication of difference, heterotopic communication , has emerged. It rests on two cultural foundations: an ideological belief in the positive, socially integrating power of communication, and a prevailing ethic of instrumental rationality, subjective individualism, and strategically practiced self-interest. The former is demonstrated by the use of simulation and spectacle as sources of information; exhibitionism/voyeurism as a communicative style; and the awareness of surveillance. The latter is seen in the competitive use of knowledge as a commodity; a surface globalism masking deep parochialism; lateral as well as vertical information inequity; and the use of public versus private as strategies for engagement rather than as spaces. Those who engage in heterotopic communication resort to their 'own devices' both in the sense of personal agendas, strategies, interests, and interpretations, and in the form of the telecommunication tools that help realize them. These personal and technological devices allow individuals with the right educational and technical resources to avoid exposure to disagreement, difference, or other information that does not serve their direct purposes or reflect their particular views of the world; yet they also help convey the appearance of openness, availability, and cooperation. This style of interaction is used strategically in combination with information and communication technologies to gain social or economic advantages, but it may encourage social separatism and parochialism, inhibit the negotiation of disputes, and emphasize competing interests. 相似文献