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注重效益,着力高效——浅谈初中物理综合实践活动的低成本性 被引量:1
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作者 谭冠男 《试题与研究(教学论坛)》 2017年第31期4-4,共1页
初中物理综合实践活动,要求以学生为 主,突破课堂的限制,走出学校和教室,回归社会和 自然,最大限度地施展个人的特长.如何使综合实践 活动大规模地开展,实践活动内容的低成本性起着 关键性的作用, 本文简要论述了综合实践活动的低 成本性.
关键词 院器材 时间 人员 低成本性
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房地产网络营销探讨
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作者 张燕 《广东白云职业技术学院广州白云工商高级技工学校学报》 2003年第2期55-58,54,共5页
20世纪90年代中期以来,随着个人电脑在全球范围的普及和信息高速公路技术的发展,一种建立在互联网基础上的新型营销方式——网络营销应运而生。它以其独具的特征和优势,带来了营销方式的变革,并将成为21世纪全球企业竞争和经营不可... 20世纪90年代中期以来,随着个人电脑在全球范围的普及和信息高速公路技术的发展,一种建立在互联网基础上的新型营销方式——网络营销应运而生。它以其独具的特征和优势,带来了营销方式的变革,并将成为21世纪全球企业竞争和经营不可缺少的工具。房地产业作为国家“十五”规划和国民经济长期发展规划的支柱产业,也面临如何将网络营销这一新形式融入自身行业发展的问题。在逐步融合的过程中,房地产网络营销显示出其独特的功能。随新经济的到来,房地产网络营销必将成为房地产营销的重要手段。 展开更多
关键词 房地产 网络营销 互联网 互动 低成本性 产品优势 价格优势 销售渠道 信息优势 竞争优势
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机械制造与自动化技术的研究
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作者 冯东闯 《科技风》 2018年第19期159-159,167,共2页
机械制造属于我国的重要产业,不仅对工业具有重要影响,同时也影响着农业以及高新技术产业,在一定程度上决定了我国的发展水平。自动化技术的产生与应用,为我国机械制造业带来了新的发展机遇,将该技术应用在机械制造业当中,可以提升机械... 机械制造属于我国的重要产业,不仅对工业具有重要影响,同时也影响着农业以及高新技术产业,在一定程度上决定了我国的发展水平。自动化技术的产生与应用,为我国机械制造业带来了新的发展机遇,将该技术应用在机械制造业当中,可以提升机械制造的效率与效益。基于此,本文首先对自动化与机械自动化进行了简单介绍,其次分析了机械制造和自动化技术的融合现状与发展前景,最后从实用性、低成本性以及配套性等方面提出了几点机械制造与自动化技术融合发展的建议,旨在为我国机械制造业的发展贡献一份力量。 展开更多
关键词 机械制造 自动化技术 低成本性
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Kinetic and Thermodynamic Studies of Acid Scarlet 3R Adsorption onto Low-cost Adsorbent Developed from Sludge and Straw 被引量:2
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作者 任晓莉 杨玲敏 刘敏 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期208-213,共6页
A low-cost adsorbent was prepared from sludge and straw by pyrolysis in a dried state with the surface area of the adsorbent of 829.49 ma. g-l, micropore volume of 0.176 cm2·g-1 and average pore radius of 5.0 nm.... A low-cost adsorbent was prepared from sludge and straw by pyrolysis in a dried state with the surface area of the adsorbent of 829.49 ma. g-l, micropore volume of 0.176 cm2·g-1 and average pore radius of 5.0 nm. The kinetic, equilibrium isotherm and thermodynamic characteristics of trisodium 1-(1-naphthylazo)-2-hydroxynaphthalene- 4',6,8-trisulphonate (acid scarlet 3R) onto the adsorbent from sludge and straw were investigated. The results indicated that the pseudo second order adsorption was the predominant adsorption mechanism of acid scarlet 3R. Thus, the adsorption phenomenon was suggested as a chemical process. The adsorption data were fitted better with Langmuir model than Freundlich model, indicating that the adsorption of acid scarlet 3R belonged to the monolayer adsorption and mainly occurred in micropores. 展开更多
关键词 KINETIC THERMODYNAMIC acid scarlet 3R ADSORBENT SLUDGE STRAW
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Multiple phase detector of M-ary phase shift keying symbols in code division multiple access systems 被引量:1
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作者 QUAN Zhi 《Journal of Central South University》 SCIE EI CAS 2011年第4期1080-1086,共7页
A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it w... A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation. 展开更多
关键词 coordinate descent COMPLEXITY M-ary phase shift keying (M-PSK) multiuser detection quadratic optimization semi-definite relaxation
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Adaptive Thermal Comfort for Occupants of Low-Cost Dwellings in a Hot Dry Climate
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作者 Irene Marincic J. Manuel Ochoa +1 位作者 M. Guadalupe Alpuche Gabriel Gomez-Azpeitia 《Journal of Civil Engineering and Architecture》 2012年第3期356-363,共8页
Adaptive models are based on the observation that there are some actions that people can and actually do take to achieve thermal comfort. Studies regarding thermal comfort conditions in economical dwellings were carri... Adaptive models are based on the observation that there are some actions that people can and actually do take to achieve thermal comfort. Studies regarding thermal comfort conditions in economical dwellings were carried out simultaneously in seven Mexican cities, corresponding to warm dry and warm humid climates. In this article, case studies of low-cost dwellings in the city of Hermosillo (in northwest Mexico), are presented and analyzed. Field surveys were carried out to obtain information about the physical characteristics of the dwellings and their occupants, as well as the indoor thermal environment. Neutral temperature was obtained from the applied survey. The high neutral temperature reveals the effect of inhabitants' adaptation mechanism to extreme climates. Occupant comfort votes as a function of indoor air temperatures were analyzed, and different characteristics such as age, size and gender were evaluated separately. The results show the variability of the neutral temperature and the tolerance to temperature changes, depending on the population's specific characteristics. In many cases where the population does not have access to artificial acclimatization devices, the neutral temperature values for specific climates and people can inform architects when choosing the most suitable thermal strategies for building design. 展开更多
关键词 Adaptive comfort low-cost dwelling hot dry climate.
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Initial alignment for low-cost attitude and heading reference systems
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作者 方斌 Chou Wusheng Ding Li 《High Technology Letters》 EI CAS 2013年第2期150-155,共6页
MEMS (micro electro mechanical systems) inertial navigation system ~, Mll'~3) nas Been WllUly used in robots for its low-cost. The MINS and magnetometers are commonly the component parts of the attitude and headin... MEMS (micro electro mechanical systems) inertial navigation system ~, Mll'~3) nas Been WllUly used in robots for its low-cost. The MINS and magnetometers are commonly the component parts of the attitude and heading reference systems (AHRS), which provide pitch and roll angles relative to the earth gravity vector, and heading angle relative to the north. However, the performance of sen- sors with low cost AHRS is not so good. The gyros are not sensitive enough to observe the earth an- gular velocity, so the traditional technique like alignment algorithm is invalid. The measurements of gyros become useless to determine the initial attitude matrix from navigation frame to body frame. The alignment algorithm is computed by the accelerometers and magnetometers. The process is es- tablished as an optimization problem of finding the maximum eigenvector. Meanwhile the sensitive analysis with respect to the biases of accelerometers is proposed. Then the recursive least squares al- gorithm (RLSA) is introduced. The comparison between the proposed method and RLSA is provid- ed. The results demonstrate its accuracy favorably and verify the feasibility of the proposed algo- rithm. 展开更多
关键词 attitude and heading reference systems (AHRS) ALIGNMENT sensitive optimiza-tion EIGENVECTOR
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A Beam Stabilization Algorithm Based on Nonlinear Observer for Low Cost Satcom-on-the-Move
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作者 TIAN Fanghao WANG Rong +1 位作者 GAO Feifei YAO Minli 《China Communications》 SCIE CSCD 2014年第A01期16-22,共7页
A beam stabilization algorithm was proposed for low cost satcom-on-the-move (SOTM) to stabilize the vehicle-mounted antenna beam. The proposed algorithm utilizes the nonlinear observel to estimate the vehicle's att... A beam stabilization algorithm was proposed for low cost satcom-on-the-move (SOTM) to stabilize the vehicle-mounted antenna beam. The proposed algorithm utilizes the nonlinear observel to estimate the vehicle's attitude information based on inertial measurement unit. Then the estimated angles and angular velocities are used to stabilize the antenna beam. Experiment results show tha| the proposed algorithm can stabilize the antenna beam when the tracking information is available, indicating that it is competent to the SOTM system. 展开更多
关键词 attitude estimation inertial measurementunit (IMU) nonlinear observ~ satellite communication.
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论新货币革命中的伦理与技术 被引量:4
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作者 骆祖望 《哲学动态》 CSSCI 北大核心 2003年第8期19-21,共3页
关键词 货币革命 高技术 低成本性 非对称 金融伦理建设
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Development and performance evaluation of an innovative low-cost seismic isolator 被引量:5
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作者 TAN Ping XU Kai +3 位作者 WANG Bin CHANG ChiaMing LIU Han ZHOU FuLin 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第10期2050-2061,共12页
This paper proposes an innovative low-cost isolator with lightweight and cost-effective features for use in low-rise residential buildings.The low-cost laminated isolator is formed by plastic shims with unsaturated po... This paper proposes an innovative low-cost isolator with lightweight and cost-effective features for use in low-rise residential buildings.The low-cost laminated isolator is formed by plastic shims with unsaturated polyester fiber reinforcement between rubber layers.Performance tests are systematically carried out to characterize the isolator in terms of mechanic behavior(e.g.,compression,shear,and their relationship),dynamic properties(e.g.,damping),and ultimate states.A design guideline and associated criteria of the low-cost isolator are also provided and discussed in this study.To investigate more detailed behavior,a finite element model of the isolator is developed in ABAQUS and calibrated by the experimental data.The research presented in this paper makes significant contributions to the evaluation of the peak stress and strain demands on isolator’s components and provides technical support for the design and manufacturing of this new type of isolator. 展开更多
关键词 seismic isolation technology elastomeric isolator simple isolator finite element analysis
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Recent progress in room-temperature sodium-ion batteries
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作者 WU XiaoYan YU JueZhi +3 位作者 WANG YueSheng MU LinQin HU YongSheng CHEN LiQuan 《Science Foundation in China》 CAS 2014年第1期57-70,共14页
Room-temperature sodium-ion batteries have attracted increasing interest in recent years because of abundant sodium reserves and the low costs.Grid-scale energy storage applications are particularly relevant to this b... Room-temperature sodium-ion batteries have attracted increasing interest in recent years because of abundant sodium reserves and the low costs.Grid-scale energy storage applications are particularly relevant to this battery technology.Here,we present our recent progress in researching room-temperature sodium-ion batteries,and focus on new electrode materials,including cathodes and anodes,for both non-aqueous and aqueous systems. 展开更多
关键词 Sodium-ion batteries CATHODE ANODE Non-aqueous electrolyte Aqueous electrolyte Solid e-lectrolyte
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