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61.
The production of bricks, one of the main components in conventional construction technology, has been carried out by either a hand moulding process or by a fully mechanized process. Both processes have limitations in developing countries. An alternative solution is the use of decentralized non-power-consuming brick making units, utilizing unconventional raw materials which do not require baking to develop strength. A manually energized brick making machine (MEBM) has proven the feasibility of extruding various mixes including a lime-fly ash-sand mixture. The production of bricks with a keyed cross-section is investigated using the MEBM to establish the functional and economic viabilities of the technology to create a construction technology which relies on abundant resources, unskilled labour and zero energy input. La production de briques, l'un des elements essentiels de la construction traditionnelle, est assuree soit par moulage manuel, soit par des procedes entierement mecanises. Les deux procedes montrent leurs limites dans les pays en voie de developpement. Une solution alternative consiste a utiliser des machines decentralisees ne consommant pas d'energie, faisant appel a des matieres premieres non conventionnelles qui n'exigent pas de cuisson pour donner la resistance a la brique. Une machine a fabriquer les briques mue par la force manuelle (manually energized brick making machine - MEBM) a prouve sa capacite a extruder differents melanges comportant un melange de chaux et de sable cendre. La production de briques a section creuse au moyen de la MEBM est a l'etude, afin d'etablir la faisabilite economique et fonctionnelle de cette technique propre a creer une technologie de construction basee sur des ressources abondantes, une main-d'oeuvre non qualifiee et une depense energetique nulle. 相似文献
62.
Substitution and price elasticity estimates using inter-country pooled data in a translog cost model
Pooled data across several developing countries and the U. S. were used to estimate long-run substitution and price elasticities in a translog framework for the paper, iron and steel, and aggregate manufacturing industries. While the quality of the estimates varies across the several industry-specific models, the results suggest higher values for these elasticities than appear commonly used in integrated assessment models. Estimates of own-price elasticities of energy range from − 0.80 to − 1.76 and are comparable to estimates from previous econometric studies in the context of developed countries (− 0.77 to − 0.87). Substitution elasticities show wider variation across countries and industries. For energy and capital they range from − 1.96 to 9.80, for labor and energy from 2.61 to 7.11, and for energy and material from − 0.26 to 2.07. 相似文献
63.
介绍中国综采设备在印度东南煤炭公司(SECL)的使用条件、支架架型与主要技术参数,对使用中工作面矿压显现进行了全面分析,并针对出现的问题和煤层埋深浅、顶板岩层坚硬难冒特点,采取地面钻孔爆破处理上覆岩层的措施,取得显著的技术经济效果。 相似文献
64.
《中国标准化(英文版)》2014,(5)
正The training on energy management system,undertaken by the Secretariat of China National Accreditation Service for Conformity Assessment(CNAS),and jointly organized by Asia-Pacific Economic Cooperation(APEC)and Pacific Accreditation Cooperation(PAC),was held in Beijing from August 12 to15,2014.The training attracted 39 workers and reviewers of energy management system accreditation institutions from countries including China,Russia,Indonesia,Malaysia,India,Vietnam,Thailand,South Korea,Japan and so on. 相似文献
65.
一项大规模地下排水研究项目RAJAD(拉贾斯坦邦农业排水研究项目),在印度的拉贾斯坦邦实施,旨在控制因灌溉引起的土壤盐碱化问题。在12个野外试验地点获得了大量的地下排水数据。田间结果表明,地下排水系统对控制土壤盐碱化具有积极意义。广泛的监测结果显示,地下排水系统是控制土壤盐碱化的有效途径。试验数据表明,有地下排水系统的所有地区,其土壤盐化度都呈现出逐渐下降的趋势。土壤的脱盐速度在排水间距较小(〈40m)时比排水间距较大时(〉40m)要快。雨季通过地下排水系统淋洗排出的盐分数量大于灌溉季节引入的盐分数量。 相似文献
66.
Patent analysts predict trends in research and the business environment by studying the numbers and classifications of patents issued to companies around the world. Those attempts are often affected by the changes taking place in international treaties, governments, patent laws, patent classification systems, and corporate mergers and acquisitions. This paper describes some of the changes in the patent information environment that have disrupted the trends predicted by patent analyses in the past. 相似文献
67.
Bridging digital divide: Efforts in India 总被引:1,自引:0,他引:1
The fruits of Information Technology sector such as the Internet blue chips, online shopping and nanosecond email have failed to cure century-old malaises like illiteracy, poverty and unemployment in India. The paper presents few facts about digital divide based on global and the USA perspective, its definition and types as global, regional and national, and societal implications. It highlights India in the context of digital divide by discussing its infrastructural bottleneck that includes electricity, IT penetration, teledensity and Internet industry, and its enabling policies to transform India as a knowledge society. It discusses various technology options for connectivity, viz. terrestrial wireless, satellite, wireline, etc. and presents snap shots of select successful projects that made an impact in helping to bridge digital divide in India, viz. passenger reservation system, Akashganga, Akshaya e-centres, Bhoomi, etc. It concludes that creation of Information and Communication Technologies infrastructure and content are the core methodologies, and a national agenda on a C-8 thrust towards: connectivity provision, content creation, capacity augmentation, core technologies creation and exploitation, cost reduction, competence building, community participation and commitment to the deprived and disadvantaged would definitely help in bridging digital divide. 相似文献
68.
Sunil K. Ambast Ashok K. Keshari Ashvani K. Gosain 《Canadian Metallurgical Quarterly》2008,134(1):13-25
Remote sensing-derived spectral data have been used in the past to partition net radiation, soil heat, and sensible heat fluxes for estimating latent heat flux as a residual of surface energy balance, and thus regional evapotranspiration. Attempts to provide a simplified procedure for estimating sensible heat flux at a regional scale have not been successful because of the relatively strong dependence of the heat transfer coefficient on the land–atmosphere boundary condition. This paper presents a remote sensing-based procedure to estimate the sensible heat flux incorporating the local meteorological conditions, and in turn to determine the regional evapotranspiration. The model utilizes satellite-derived surface albedo, surface temperature, and leaf area index along with a very few agrometeorological data as inputs. The proposed procedure has been tested on a part of the Western Yamuna Canal system, India, and is found to be computationally simple as well as stable. For a well-watered wheat crop, the average evapotranspiration by the proposed model is estimated to be 2.05?mm?d?1 on January 30, 1996, whereas it is estimated to be 1.89?mm?d?1 using the Penman-Monteith equation, indicating a difference of less than 10%. The model is subjected to sensitivity analysis for uncertainties in the observed wind velocity and the computed leaf area index (by ±20%) to estimate sensible heat flux. Results reveal that the percentage change in mean sensible heat flux for the image is less than 5% in all cases, thus indicating the acceptability of the model against the uncertainties. Further, the model has been applied to three sets of Landsat-TM data covering the Sone Low Level Canal system, India, to demonstrate its usefulness in evaluating water delivery performance. 相似文献
69.
The California Psychological Inventory (CPI) seeks to assess culturally universal dimensions of personality, i.e, "folk concepts." Validation must therefore include cross-cultural validation. The CPI Socialization (So) scale was translated into Hindi and Punjabi and given to 203 delinquents and 48 college students in India. Behavioral ratings were assigned, 4 to nondelinquents, 3 to casual and 1st offenders, 2 to habitual offenders, and 1 to hardened and habitual offenders. The ratings correlated +.70 with So in the full sample (N = 251), and +.73 within the subsample of 203 delinquents. A coefficient of +.73 had also been observed for 10,296 males tested in the USA. Findings are interpreted as supporting the theoretical presuppositions and practical utility of the measure. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Further research is necessary to optimize the composition of flyash, clay, sand, lime, cement and moisture content to bring the project forward to production stage. The authors invite participation in the next detailed stage. 相似文献