检索结果-南通市图书馆

Experimental evaluation of a“u”type earth-to-air heat exchanger planned for narrow installation space in warm climatic conditions

引用

Energy and Built Environment 2024年第5期5卷 772-786页

作者： Ricardo Molina-Rodea Jorge Alejandro Wong-Loya Hugo Pocasangre-chávez Jennifer Reyna-Guillén Institute of Renewable Energies National Autonomous University of MexicoTemixcoMorelosMexico

The thermal performance of a“u”type earth-to-air heat exchanger is presented in this experimental *** device has a serial-connected vertical *** wells where tubes were installed have a depth of fewer than 3 m and are separated every 1.5 m,using an installation area of *** experimentation was carried out in March in Morelos,Mexico when the environmental temperature reaches 35℃ during the *** performance of the device was measured and compared to the requirements of an office for cooling purposes within a university campus to reproduce the space restrictions found in urbanized *** using a small land surface,it is feasible for urbanized *** air temperature inside the“u”type earth-to-air heat exchanger,the surrounding soil temperature,the airspeed,and the power consumed by the fan were *** air temperature and the fan’s power consumption data were obtained by modifying the airspeed in four constant values,from 1.3 m/s to 6.6 m/*** show that the device evaluated in this work has adequate thermal performance for cooling purposes compared to the requirements of an office.A decrease in air temperature was recorded in a range of 5.1℃ to 9.4℃.Over 70%of the total temperature difference was reached in the first well,where the average soil thermal disturbance at 5 cm was 2.8℃.The device achieved a maximum COP of 12.8 and a maximum effectiveness of 88.4%.With these results,it is concluded that the system is suitable for cooling purposes in areas with space *** work is novel since the dimensions available for installation in urbanized areas are considered and compared with the thermal requirements of an *** addition to the fact that there are no published works with vertical heat exchangers connected in series.

关键词： Low temperature geothermal energy Thermal performance Vertical heat exchangers Space restrictions in urbanized areas Geothermal direct uses

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Generating Baikal-GVD high energy cascade-like neutrino events with a GEANT4-based simulation toolkit

引用

chinese Physics C 2024年第10期48卷 256-263页

作者： Zike Wang A.D.Avrorin zhen Cao Mingjun chen Peiyuan chu zh.-A.M.Dzhilkibaev Bo Gao Tianqi Huang Jiali Liu Ying Qi Xiaohao You D.N.Zaborov Key Laboratory of Particle Astrophysics Experimental Physics Division&Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China university of chinese Academy of Sciences Beijing 100049China Institute for Nuclear Research of the Russian Academy of Sciences Moscow 117312Russia TIANFu Cosmic Ray Research Center Chengdu 610213China School of Science Tibet UniversityLhasa 850000China

using the GEANT4 and Cosmic Ray Monte Carlo(CRMC)software packages,we developed a new simulation toolkit for astrophysical neutrino *** configuring the Baikal-GVD detector and comparing the vertex position and direction of incident particles,as well as the channel-by-channel signals,to the events detected by Baikal-GVD,we successfully generated 13 high-energy cascade neutrino events with the *** analysis revealed a systematic offset between the reconstructed shower position and the true interaction position,with a distance close to the scale of the shower maximum of−0.54±1.29 *** achieved a good linear relationship between the photoelectron number of neutrino events obtained by simulation and the real data measured by *** simulation toolkit could serve as a reliable basis for studying the performance of astrophysical neutrino telescopes.

关键词： high-energy neutrino cascade event simulation cherenkov

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

自推进胶囊在小肠中移动时的优化控制

引用

机械工程学报 2024年

作者：廖茂林李智朱佳鹏王泽旭 JOSEPHPáez chávez 北京科技大学机械工程学院北京科技大学井下智能控制研究院德累斯顿工业大学动力学研究中心

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了... 详细信息

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了扩张段和狭窄段的小肠-胶囊耦合动力学模型，并以小肠多变的摩擦环境以及对胶囊的包裹程度不同作为不稳定因素，分析了自推进胶囊的动力学行为规律。基于此，同时以胶囊的移动速度、单位能耗和对小肠壁冲击力作为优化目标，采用(Six-Sigma+NSGA-II+Monte-Carlo)组合优化算法获取胶囊可控移动对应的参数组合区间。最终，结合ADAMS动力学仿真与实验测试验证了当采用优化后的参数组合控制自推进胶囊时，可使其实现低能耗低冲击的定速定向移动。

关键词：小肠胶囊非光滑多目标优化运动控制

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

RATIONAL GENERAL SOLuTIONS OF HIGHER ORDER ALGEBRAIC ODES

引用

Journal of Systems Science & Complexity 2013年第2期26卷 261-280页

作者： HuANG Yanli NG L X chu WINKLER Franz School of Computer Science and Software Engineering Tianjin Polytechnic University Research Institute for Symbolic Computation(RISC) Johannes Kepler University Department of Mathematics Quy Nhon University

This paper generalizes the method of Ng6 and Winkler （2010, 2011） for finding rational general solutions of a first order non-autonomous algebraic ordinary differential equation （AODE） to the case of a higher order AODE, provided a proper parametrization of its solution hypersurface. The authors reduce the problem of finding the rational general solution of a higher order AODE to finding the rational general solution of an associated system. The rational general solutions of the original AODE and its associated system are in computable 1-1 correspondence. The authors give necessary and sufficient conditions for the associated system to have a rational solution based on proper reparametrization of invariant algebraic space curves. The authors also relate invariant space curves to first integrals and characterize rationally solvable systems by rational first integrals.

关键词： Algebraic ODE associated system invariant algebraic space curve rational first integral rational general solution.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Designing a practical ATM Campus Network

引用

High Technology Letters 1995年第1期1卷 61-65页

作者： Bin, L. Yong, zh. Shiduan, ch. Yan, M. Beijing univ of Posts and Telecommunications Beijing China

A typical distributed ATM campus network——BuPT(Beijing university of Posts andTelecommunications)ATM Campus Network is presented in this *** network iscomposed of several small ATM switches in a distributed manner and will be connected tothe china Education and Research Network(CERNET).First,an architecture of BuPTATM Campus Network is *** the interworking and protocol conversion be-tween ATM network and existing 802.X LAN are ***,some of the typicalbroadband applications such as multimedia communications,virtual workgroups,remotevideo-teaching and LAN emulation are described.

关键词： ATM Campus network LAN CERNET Broadband services

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Studies on Thermal Conductivity of Diamond Film

引用

High Technology Letters 1995年第1期1卷 91-94页

作者： Jingbiao, C. Hong, ch. Jifa, zh. Dayan, B. Rongchuan, F. univ of Science and Technology of China Hefei China

Diamond films were prepared by electron-assisted chemical vapor deposition (EACVD) system, and the thermal diffusivities of the films with or without substrate were studied by use of photothermal deflection (PTD) technique. The results show that less non-diamond component and larger crystalline size result in higher thermal conductivity of CVD diamond film. The influence of substrate on the measurement of thermal conductivity of the film was investigated, and a simple two-layer heat conduction model is given to account for the influence and used to draw the thermal conductivity of the film from the effective thermal diffusivity of film/substrate system.

关键词： Diamond film Photothermal deflection Thermal conductivity Substrate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Polygeneration Study of Low-to-Medium Enthalpy Geothermal Reservoirs in Mexico

引用

Journal of Thermal Science 2021年第3期30卷 1077-1087页

作者： chÁVEZ Oscar GODÍNEZ Francisco Tecnológico Nacional de México/I.T.chihuahua.Av.Tecnológico 2909 C.P.31310ChihuahuaChihuahuaMéxico Instituto de Ingeniería Universidad Nacional Autónoma de MéxicoUNAMC.U.Ciudad de MéxicoC.P.04510México Polo universitario de Tecnología Avanzada Universidad Nacional Autónoma de MéxicoVía de la Innovación No.410Autopista Monterrey-Aeropuertokm.10 PIITC.P.66629Apodaca Nuevo LeónMéxico

This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their *** reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal *** heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction *** predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat *** developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 *** also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.

关键词： polygeneration system geothermal reservoir local thermal equilibrium low-to-medium enthalpy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

2001—2021年中国湿地碳汇研究进展与热点趋势分析

引用

湿地科学与管理 2024年第1期20卷 70-75页

作者：何苏南王凯郁凯孙果丽朱小梅陈环宇邢锦城乔干群卢明海江苏沿海地区农业科学研究所江苏盐城224000 江苏银宝控股集团有限公司江苏盐城224000

明确湿地碳汇研究进展对于寻找突破点和研究方向具有重要意义。利用CiteSpace软件对中国知网2001—2021年湿地碳含量研究的1183条文献进行了发文量、研究团队、研究机构、研究热点等的可视化分析,得出我国湿地碳汇研究特点和发展趋势。... 详细信息

明确湿地碳汇研究进展对于寻找突破点和研究方向具有重要意义。利用CiteSpace软件对中国知网2001—2021年湿地碳含量研究的1183条文献进行了发文量、研究团队、研究机构、研究热点等的可视化分析,得出我国湿地碳汇研究特点和发展趋势。结果表明:1)2005年后发文量显著增长,2017年达到顶峰后呈波动增加趋势;2)中科院东北地理与农业生态研究所、东北林业大学、北京师范大学是我国湿地碳汇研究的主要机构;3)我国湿地碳汇研究从湿地—气候变化的响应关系起步,发展到湿地土壤修复模式的探究,现阶段主要为碳中和背景下湿地固碳植物的选育与驯化;4)我国湿地碳汇研究稳步发展,但仍存在湿地碳汇计算综合评价体系缺乏、较少从湿地修复与保护双角度出发去考虑湿地碳库在“碳中和”中的相关影响问题。本研究指出了加强区域合作,结合本土化数据构建我国湿地碳汇参数库可能是未来研究的重要课题。

关键词：湿地碳汇 CiteSpace 可视化分析

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

资本主义社会片面追求效率与休闲的异化

引用

消费经济 2005年第6期21卷 68-71页

作者：周觉北京信息科技大学经贸系北京100085

追求劳动效率推动了资本主义社会由追求绝对剩余价值向相对剩余价值转变,马克思指出这种转变给劳动者所带来的后果是劳动强度的增加与劳动的异化。劳动的异化会导致休闲的异化,表现为休闲的“物化”与“工作化”;劳动生产效率提高要求... 详细信息

追求劳动效率推动了资本主义社会由追求绝对剩余价值向相对剩余价值转变,马克思指出这种转变给劳动者所带来的后果是劳动强度的增加与劳动的异化。劳动的异化会导致休闲的异化,表现为休闲的“物化”与“工作化”;劳动生产效率提高要求休闲效率也相应提高,追求休闲效率在加剧时间稀缺性的同时导致休闲异化,表现为自由时间之不可能。

关键词：效率休闲异化

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electronic Absorption Spectroscopy of H2X （X=O, Te, Po）： Theoretical Treatment of Spin-Orbit Effects

引用

chinese Journal of chemical Physics 2009年第2期22卷 171-177页

作者： chérif A. A. Ndoye chantal Daniel Laboratoire de chimie Quantique Institut de Chimie UMR 7177 CNRS-Université de Strasbourg 4 Rue Blaise Pascal 67000 Strasbourg France

The electronic spectroscopy of H2X （X=O, Te, Po） was investigated by means of spinorbit configuration interaction （EPCISO） and restricted active space state interaction （SORASSI）. The transition energies to the low-lying singlet and triplet states of H2O, in which the SO interaction is zero, compare rather well with the experimental data as well as to other theoretical values. The theoretical electronic absorption spectrum is characterized by three allowed transitions A^1B1 （2px（O）→σ^＊g/3s（O））, B^1A1（σg→σ^＊g/3s（O）） and A^1S2（σg→σ^＊u） calculated at 7.68, 9.94, and 11.72 eV, respectively. The theoretical absorption spectra of H2X （X=Te, Po） are shifted to the red with the A^1B1 （npx（X）→σ^＊g） states calculated at 5.06 eV （H2Te） and 4.40 eV （H2Po） and the A^1B2 （σg→σ^＊u） states calculated at 7.89 eV （H2Te） and 7.77 eV （H2Po）. The largest SO splitting amounts to 0.34 eV and is found for the lowest a^3A1 of H2Po. In H2Te the SO effects are still negligible with a maximum splitting of 0.04 eV for the lowest a^3B2. The two methods lead to comparable results but the EPCISO approach depends strongly on the reference wavefunction.

关键词： Spin-orbit Excited state Group Ⅵ dihydride

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：