资源类型

期刊论文 475

会议视频 11

会议信息 1

年份

2024 1

2023 45

2022 45

2021 36

2020 37

2019 18

2018 29

2017 26

2016 17

2015 28

2014 16

2013 17

2012 8

2011 17

2010 14

2009 11

2008 25

2007 22

2006 24

2005 7

展开 ︾

关键词

中国航天 5

航天 5

发展战略 3

2022全球十大工程成就 2

2023全球十大工程成就 2

信息处理 2

农业面源污染 2

创新 2

卫星 2

卫星应用 2

发展规划 2

发展趋势 2

实时服务 2

微波遥感 2

技术创新 2

1)幂模型 1

2R-1C模型;嵌入式系统;参数估计;非迭代方法;二次型 1

3D细胞容器 1

ARMA模型 1

展开 ︾

检索范围:

排序: 展示方式:

Effect of heat transfer space non-uniformity of combustion chamber components on in-cylinder heat transfer

Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,

《能源前沿(英文)》 2010年 第4卷 第3期   页码 392-401 doi: 10.1007/s11708-009-0066-1

摘要: Combustion chamber components (cylinder head-cylinder liner-piston assembly-oil film) were treated as a coupled body. Based on the three-dimensional numerical simulation of the heat transfer of the coupled body, a coupled three-dimensional calculation model for the in-cylinder working process and the combustion chamber components was built with domain decomposition and boundary coupling method, which adopts the coupled three-dimensional simulation of in-cylinder working process and the combustion chamber components. The model was applied in the investigation of the influence of space non-uniformity in heat transfer among combustion chamber components on in-cylinder heat transfer. The results show that the effect of wall temperature space non-uniform distribution of combustion chamber components on heat transfer happens mainly at the end of the compression stroke and expansion stroke. Therefore, it can be concluded that wall temperature space non-uniform distribution of combustion chamber components would influence heat transfer during the intake and exhaust stroke obviously.

关键词: heat transfer     space non-uniformity     soot emission     in-cylinder     diesel    

FULL TIME-SPACE GOVERNANCE STRATEGY AND TECHNOLOGY FOR CROPLAND NON-POINT POLLUTION CONTROL IN CHINA

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 593-606 doi: 10.15302/J-FASE-2023522

摘要:

Ensuring food safety while reducing agricultural non-point source pollution is quite challenging, especially in developing and underdeveloped countries. Effective systematic strategies and comprehensive technologies need to be developed for agricultural non-point source pollution control at the watershed scale to improve surface water quality. In this review, a proposal is made for a full time-space governance strategy that prioritizes source management followed by endpoint water pollution control. The 4R chain technology system is specifically reviewed, including source reduction, process retention, nutrient reuse and water restoration. The 4R chain technology system with the full time-space governance strategy was applied at the scale of an administrative village and proved to be a feasible solution for reducing agricultural non-point source pollution in China. In the future, a monitoring system needs to be established to trace N and P transport. Additionally, new smart fertilizer and intelligent equipment need to be developed, and relevant governance standards and supportive policies need to be set to enhance the efficacy of agricultural non-point source pollution control.

关键词: 4R chain technology system     agricultural non-point source pollution     case study     full time-space governance strategy    

Primary spinal epidural non-Hodgkin’s lymphoma presented with spinal cord compression syndrome

Chunquan CAI MD, PhD, Qingjiang ZHANG BM, Changhong SHEN MD, PhD,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 499-502 doi: 10.1007/s11684-009-0075-9

摘要: The spinal epidural space is an uncommon presenting site in primary non-Hodgkin’s lymphomas, especially for children. A boy suffered spinal cord compression syndrome caused by primary spinal epidural non-Hodgkin’s lymphoma. Thoracolumbar magnetic resonance imaging (MRI) demonstrated an intraspinal mass. An operation was performed with gross total tumor removal. Histological examination revealed a non-Hodgkin’s B-cell lymphoma. Bone marrow aspiration was negative for lymphoma involvement. No other therapies (chemotherapy and/or radiotherapy) were performed according to the parents’ opinion. The patient died approximately one year after the operation due to brain metastases. The clinical course and imaging features were discussed with a review of literatures.

关键词: non-Hodgkin’     s lymphoma     primary     spinal cord compression syndrome     epidural space    

异形掘进机设计制造关键技术研究及工程应用

李建斌

《工程(英文)》 2017年 第3卷 第6期   页码 905-914 doi: 10.1016/j.eng.2017.12.002

摘要:
随着地下空间开发进程的加快,越来越多的大型掘进机(TBM)应用于地下工程开挖。目前,常规TBM 已无法完全满足地下工程对断面形式和空间利用率的追求,异形TBM 成为理想断面开挖设备成为市场新的增长点。本文首先介绍了异形TBM 的技术特点及发展现状,然后结合典型工程与工法创新,针对矩形顶管和马蹄形TBM 开展了盾体结构设计优化、多刀盘联合开挖、异形管片拼装、黄土地层渣土改良等多项关键技术研究,为异形断面TBM 的设计、制造和施工提供了一套可行的解决方案。相关工程实践表明,采用针对性设计、制造的异形TBM,在施工进度、地表沉降控制和空间利用等方面具有巨大优势。

关键词: 异形TBM     矩形顶管机     马蹄形TBM     地下空间开发    

DEVELOPMENT OF AN AUTOMATIC WEIGHING PLATFORM FOR MONITORING BODYWEIGHT OF BROILER CHICKENS IN COMMERCIAL PRODUCTION

《农业科学与工程前沿(英文)》 2023年 第10卷 第3期   页码 363-373 doi: 10.15302/J-FASE-2023510

摘要:

● An automatic weighing system for monitoring bodyweight of broilers was developed.

关键词: automatic weighing     weight monitoring     floor housing     uniformity     precision poultry farming    

非理想条件下空分复用研究与应用 None

Ji-ying XIANG

《信息与电子工程前沿(英文)》 2018年 第19卷 第3期   页码 357-366 doi: 10.1631/FITEE.1700827

摘要: 对空分复用技术中的非理想因素进行了理论分析,并探讨了在上述非理想工程条件下空分复用的应用,给出了实测数据。对于信道条件非理想的场景,即多通道之间相关性高,条件数大,导致高层间干扰,需要通过最优化用户匹配和降维达到最优容量。对于信道测量非理想的场景,深入分析了反馈式和非反馈式的优劣,并指出即使信道不满足互易性条件,非反馈式也是优选方法。针对上述问题,进行了理论分析和外场实测。

关键词: 第五代移动通讯;条件数;信道互易性;信道反馈测量模式;信道非反馈式测量模式    

The “Tiangong” Chinese Space Station project

Yang HONG

《工程管理前沿(英文)》 2018年 第5卷 第2期   页码 278-283 doi: 10.15302/J-FEM-2018202

关键词: manned space station     space station project     basic design    

Application and development of modern long-span space structures in China

Shilin DONG, Yang ZHAO, Dong XING

《结构与土木工程前沿(英文)》 2012年 第6卷 第3期   页码 224-239 doi: 10.1007/s11709-012-0166-6

摘要: Modern long-span space structures, developed during the 1970s and 1980s, are light and effective structures based on new technologies and light-weight high-strength materials, such as membranes and steel cables. These structures include air-supported membrane structures, cable-membrane structures, cable truss structures, beam string structures, suspen-domes, cable domes, composite structures of cable dome and single-layer lattice shell, Tensairity structures and so forth. For the premodern space structures widely used since the mid-twentieth century (such as thin shells, space trusses, lattice shells and ordinary cable structures), new space structures have been developed by the combination of different structural forms and materials. The application of prestressing technology and the innovation of structural concepts and configurations are also associated with modern space structures, including composite space trusses, open-web grid structures, polyhedron space frame structures, partial double-layer lattice shells, cable-stayed grid structures, tree-type structures, prestressed segmental steel structures and so forth. This paper provides a review of the structural characteristics and practical applications in China of modern rigid space structures, modern flexible space structures and modern rigid-flexible combined space structures.

关键词: modern long-span space structures     rigid space structures     flexible space structures     rigid-flexible combined space structures     application and development    

统筹空间科学、空间技术、空间应用协调发展的思考

周建平,吴季

《中国工程科学》 2023年 第25卷 第2期   页码 59-66 doi: 10.15302/J-SSCAE-2023.02.007

摘要:

我国航天事业因历史原因和投入限制,在初期以空间技术、空间应用为主,对空间科学重视不足,空间科学、空间技术、空间应用基本上是独立发展的;着眼新时期航天强国建设,需要将空间技术的发展深度融合到空间科学、空间应用中去,从而创造新的机遇和成就。本文剖析了空间科学、空间技术、空间应用的基本内涵并明确三者的相互关系,在系统分析国际空间科学、空间技术、空间应用的整体态势,细致梳理我国相关领域发展情况的基础上,论证了统筹我国空间科学、空间技术、空间应用协调发展的必要性,凝练了三者协调发展面临的主要问题。空间科学、空间技术、空间应用之间既有需求交叉,又可互促带动,应在规划、部署、实施的全过程中进行统筹考虑:发挥新型举国体制优势,在统一管理下做好顶层规划;坚持创新驱动发展战略,以技术进步抢占国际航天制高点;支持空间领域基础研究,培育高水平的科学家和工程师队伍;加强资源统筹协调,促进空间应用数据的合理开放和充分利用。

关键词: 航天事业;空间科学;空间技术;空间应用;协调发展;数据开放共享    

Knife-edge technique for laser cooling

WANG Zhanshan, MA Shanshan, MA Yan, ZHAO Min, LIU Hengbiao

《机械工程前沿(英文)》 2007年 第2卷 第4期   页码 468-473 doi: 10.1007/s11465-007-0081-z

摘要: The transfer characteristics of an atomic beam and the effect of laser were investigated in this paper. In the application of knife-edge technique, the temperature of atoms through laser cooling was measured. Results indicate that, after atoms are emitted from an atomic oven, the longer the atoms move, the worse the distribution of the atomic beam shows, regardless the laser cooling is taken or not. Laser cooling can reduce the transverse velocity of the atomic beam to several orders of magnitude and also increase the uniformity of an atomic beam. Knife-edge technique can measure the temperature of an atomic beam through laser cooling. The measurement accuracy depends on the pixel size of the charge coupled device (CCD), which is used for the fluorescent imaging of the atomic beam. The results are very important for the future experiments of laser cooling.

关键词: knife-edge technique     uniformity     coupled     transfer     fluorescent    

空间物理和空间天气探测与研究

王赤

《中国工程科学》 2008年 第10卷 第6期   页码 41-45

摘要:

空间物理学是1957年人造卫星发射成功后迅速发展起来的一门交叉学科。近50年来,空间已成为人类生存的第四环境,其重要性日益突出。20世纪90年代初,空间物理学与空间应用的密切结合产生了专门研究和预报空间环境中灾害性过程及其变化规律,减轻或防止空间灾害并为人类活动服务的空间天气学。文章简要总结了国外及国内空间物理和空间天气探测的历程和发展趋势,并提出对我国未来空间物理和空间天气探测发展规划和探测路线图的几点建议。

关键词: 空间物理     空间天气     空间物理探测     发展规划    

深空安全研究现状与未来发展

吴克,张哲,杨文飞,何建峰,张天柱,简抗抗,吴伟仁

《中国工程科学》 2022年 第24卷 第4期   页码 240-248 doi: 10.15302/J-SSCAE-2022.04.023

摘要: Managing space radiation risk in the new era of space exploration [R].Managing space radiation risk in the new era of space exploration [R].Human space exploration the next fifty years [J].Human space exploration the next fifty years [J].Human space exploration the next fifty years [J].

关键词: 深空安全     空间辐射威胁     行星保护     太空遗产保护     空间立法    

Modeling and optimization of an enhanced battery thermal management system in electric vehicles

Mao LI, Yuanzhi LIU, Xiaobang WANG, Jie ZHANG

《机械工程前沿(英文)》 2019年 第14卷 第1期   页码 65-75 doi: 10.1007/s11465-018-0520-z

摘要: This paper models and optimizes an air-based battery thermal management system (BTMS) in a battery module with 36 battery lithium-ion cells. A design of experiments is performed to study the effects of three key parameters (i.e., mass flow rate of cooling air, heat flux from the battery cell to the cooling air, and passage spacing size) on the battery thermal performance. Three metrics are used to evaluate the BTMS thermal performance, including (i) the maximum temperature in the battery module, (ii) the temperature uniformity in the battery module, and (iii) the pressure drop. It is found that (i) increasing the total mass flow rate may result in a more non-uniform distribution of the passage mass flow rate among passages, and (ii) a large passage spacing size may worsen the temperature uniformity on the battery walls. Optimization is also performed to optimize the passage spacing size. Results show that the maximum temperature difference of the cooling air in passages is reduced from 23.9 to 2.1 K by 91.2%, and the maximum temperature difference among the battery cells is reduced from 25.7 to 6.4 K by 75.1%.

关键词: thermal management     electric vehicle     lithium-ion battery     temperature uniformity     design optimization    

Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive

《化学科学与工程前沿(英文)》   页码 1623-1631 doi: 10.1007/s11705-022-2202-y

摘要: The number of active components and their dispersion degree are two key factors affecting the performance of adsorbents. Here, we report a simple but efficient strategy for dispersing active components by using a confined space, which is formed by mesoporous silica walls and templates in the as-prepared SBA-15 (AS). Such a confined space does not exist in the conventional support, calcined SBA-15, which does not contain a template. The Cu and Zn precursors were introduced to the confined space in the AS and were converted to CuO and ZnO during calcination, during which the template was also removed. The results show that up to 5 mmol·g–1 of CuO and ZnO can be well dispersed; however, severe aggregation of both oxides takes place in the sample derived from the calcined SBA-15 with the same loading. Confined space in the AS and the strong interactions caused by the abundant hydroxyl groups are responsible for the dispersion of CuO and ZnO. The bimetallic materials were employed for the adsorptive separation of propene and propane. The samples prepared from the as-prepared SBA-15 showed superior performance to their counterparts from the calcined SBA-15 in terms of both adsorption capacity of propene and selectivity for propene/propane.

关键词: bimetallic adsorbents     confined space     mesoporous silica     propene/propane separation    

Corrosion damage assessment and monitoring of large steel space structures

Bo CHEN, You-Lin XU, Weilian QU,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 354-369 doi: 10.1007/s11709-010-0088-0

摘要: Large steel space structures, when exposed to a harsh corrosive environment, are inevitably subjected to atmospheric corrosion and stress corrosion cracking. This paper proposes a framework for assessing the corrosion damage of large steel space structures subjected to both stress corrosion cracking and atmospheric corrosion. The empirical model for estimating atmospheric corrosion based on measured information is briefly introduced. The proposed framework is applied to a real large steel space structure built in the southern coastal area in China to assess its corrosion damage and investigate the effects of atmospheric corrosion on stress corrosion cracking. Based on the results, the conceptual design of the corrosion monitoring system of large steel space structures is finally conducted as the first step for a real corrosion monitoring system.

关键词: large steel space structure     atmospheric corrosion     stress corrosion cracking     corrosion damage     damage assessment     monitoring system    

标题 作者 时间 类型 操作

Effect of heat transfer space non-uniformity of combustion chamber components on in-cylinder heat transfer

Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,

期刊论文

FULL TIME-SPACE GOVERNANCE STRATEGY AND TECHNOLOGY FOR CROPLAND NON-POINT POLLUTION CONTROL IN CHINA

期刊论文

Primary spinal epidural non-Hodgkin’s lymphoma presented with spinal cord compression syndrome

Chunquan CAI MD, PhD, Qingjiang ZHANG BM, Changhong SHEN MD, PhD,

期刊论文

异形掘进机设计制造关键技术研究及工程应用

李建斌

期刊论文

DEVELOPMENT OF AN AUTOMATIC WEIGHING PLATFORM FOR MONITORING BODYWEIGHT OF BROILER CHICKENS IN COMMERCIAL PRODUCTION

期刊论文

非理想条件下空分复用研究与应用

Ji-ying XIANG

期刊论文

The “Tiangong” Chinese Space Station project

Yang HONG

期刊论文

Application and development of modern long-span space structures in China

Shilin DONG, Yang ZHAO, Dong XING

期刊论文

统筹空间科学、空间技术、空间应用协调发展的思考

周建平,吴季

期刊论文

Knife-edge technique for laser cooling

WANG Zhanshan, MA Shanshan, MA Yan, ZHAO Min, LIU Hengbiao

期刊论文

空间物理和空间天气探测与研究

王赤

期刊论文

深空安全研究现状与未来发展

吴克,张哲,杨文飞,何建峰,张天柱,简抗抗,吴伟仁

期刊论文

Modeling and optimization of an enhanced battery thermal management system in electric vehicles

Mao LI, Yuanzhi LIU, Xiaobang WANG, Jie ZHANG

期刊论文

Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive

期刊论文

Corrosion damage assessment and monitoring of large steel space structures

Bo CHEN, You-Lin XU, Weilian QU,

期刊论文