Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, im...Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, improved safety, and access to new products and processes are directed to the microreaction technology. Microfluidic mixer is the most important component in microfluidic devices. Based on various principles, active and passive micromixers have been designed and investigated. This review is focused on the recent developments in microfluidic mixers. An overview of the flow phenomena and mixing characteristics in active and passive micromixers is presented, including the types of physical phenomena and their utilization in micromixers. Due to the simple fabrication technology and the easy implementation in a complex microfluidic system, T-micromixer is highlighted as an example to illustrate the effect of design and operating parameters on mixing efficiency and fuid flow inside microfluidic mixers.展开更多
Steel jacket-type platforms are the common kind of the offshore structures and health monitoring is an important issue in their safety assessment. In the present study, a new damage detection method is adopted for thi...Steel jacket-type platforms are the common kind of the offshore structures and health monitoring is an important issue in their safety assessment. In the present study, a new damage detection method is adopted for this kind of structures and inspected experimentally by use of a laboratory model. The method is investigated for developing the robust damage detection technique which is less sensitive to both measurement and analytical model uncertainties. For this purpose, incorporation of the artificial immune system with weighted attributes （AISWA） method into finite element （FE） model updating is proposed and compared with other methods for exploring its effectiveness in damage identification. Based on mimicking immune recognition, noise simulation and attributes weighting, the method offers important advantages and has high success rates. Therefore, it is proposed as a suitable method for the detection of the failures in the large civil engineering structures with complicated structural geometry, such as the considered case study.展开更多
This paper presented an idea to replace the traditionally expensive parallel machines by heterogeneous cluster of workstations. To emphasise the usability of cluster of workstations platform for parallel and distribut...This paper presented an idea to replace the traditionally expensive parallel machines by heterogeneous cluster of workstations. To emphasise the usability of cluster of workstations platform for parallel and distributed computing, also the paper presented the status report on the effort and experiences for the implementation of a dynamic load balancing for parallel tree computation depth first search(DFS) on the cluster of a workstations project. It compared the speedup performance obtained from our platform with that obtained from the traditional one. The speedup results show that cluster of workstations can be a serious alternative to the expensive parallel machines.展开更多
The detailed groundwater flow and water chemistry to illustrate landscape structure of the infertile peatless mire by using piezometers and groundwater wells were measured. The instruments were installed in lines thro...The detailed groundwater flow and water chemistry to illustrate landscape structure of the infertile peatless mire by using piezometers and groundwater wells were measured. The instruments were installed in lines through a small spring-fed wetland underlying little peat from the hillslope to the valley bottom in southwestern Japan. Flow net and EC data clearly indicated that the wetland was situated in a high-EC groundwater upspring area. The low-productivity graminous vegetation was related with four hydrological factors such as: (1) high water level; (2) low-EC(<25 micro S/cm) groundwater; (3) weakly upward hydraulic gradient; and (4) overflowing of negatively pressured groundwater. In other words, the “old or deep groundwater” constructed the foundation of slope-wetland, and maintained the high groundwater level. In contrast, overflowing “youthful groundwater” is supplied from head of slope-wetland preferentially through the shallow substratum. The plant communities of the peatless mire in southwestern Japan are similar to those of raised bog in northern cool temperate Japan. There have been some reports verifying that the underlying mineral substrata of such wetlands were quartzile rocks such as granite, rhyolite, chart and well-leached sand. Results showed (1) low cation availability affects the water acidity; (2) upward seepage of high-EC groundwater composed the foundation of the investigated peatless mire; and (3) the poor mineral condition seems to play a similar role to northern ombrotrophic(rain-fed) condition.展开更多
Purpose: To identify a new syndrome that might occur following LASIK, and to point out causes, deferential diagnosis and the treatment of this new syndrome. Design: retrospective observational non-comparative study. M...Purpose: To identify a new syndrome that might occur following LASIK, and to point out causes, deferential diagnosis and the treatment of this new syndrome. Design: retrospective observational non-comparative study. Methods: 13 eyes (8 patients) had developed late onset DLK-like reaction after uneventful LASIK procedure. The patients were divided into 2 groups, group I (GI):展开更多
国际新媒体联盟(New Media Consortium,简称NMC)所发布的年度地平线报告已经成为全球范围内教育信息化发展的显示器与风向标。2012年10月,北京开放大学与美国新媒体联盟签署协议,授权北京开放大学作为其在中国发行其年度报告中文版的唯...国际新媒体联盟(New Media Consortium,简称NMC)所发布的年度地平线报告已经成为全球范围内教育信息化发展的显示器与风向标。2012年10月,北京开放大学与美国新媒体联盟签署协议,授权北京开放大学作为其在中国发行其年度报告中文版的唯一官方机构。本期学报正式刊出的2013年度地平线报告显示,未来五年内影响高等教育的六大技术为:大规模开放网络课程、平板电脑、游戏和游戏化、学习分析技术、3D打印技术、可穿戴技术。这些新技术对于我们生活中的沟通交流、获取信息、社会交往、日常学习等方面正在产生重大而深远的影响。希望本报告能够有助于国内同行及时了解国际范围内教育信息化的发展趋势、新技术应用,为促进信息技术更有效地提高教学质量服务提供有益借鉴。新媒体联盟总裁莱瑞博士(Larry Johnson)专门写信祝贺2013年度地平线报告(中文版)刊出:"北京开放大学与新媒体联盟的合作已使成千上万的中国教育界同行有机会围绕教育技术及其在大学和中小学课堂应用问题参与全球对话。北京开放大学以其在教育技术、在线学习的实践探索及开展的国际合作等方面取得的业绩成为国际地平线项目有价值的合作者。你们为地平线专题研究做出了贡献,还承担了地平线报告(中文版)的翻译出版。借助你们的帮助,许多国外同行开始了解信息技术如何在中国这一人口大国的大学和中小学得到应用;同时,也使中国教育界了解世界各国同行正在开展的信息化实践探索。"展开更多
基金the National High Technology Research and Development Program of China(2006AA030202,2006AA05Z316)
文摘Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, improved safety, and access to new products and processes are directed to the microreaction technology. Microfluidic mixer is the most important component in microfluidic devices. Based on various principles, active and passive micromixers have been designed and investigated. This review is focused on the recent developments in microfluidic mixers. An overview of the flow phenomena and mixing characteristics in active and passive micromixers is presented, including the types of physical phenomena and their utilization in micromixers. Due to the simple fabrication technology and the easy implementation in a complex microfluidic system, T-micromixer is highlighted as an example to illustrate the effect of design and operating parameters on mixing efficiency and fuid flow inside microfluidic mixers.
文摘Steel jacket-type platforms are the common kind of the offshore structures and health monitoring is an important issue in their safety assessment. In the present study, a new damage detection method is adopted for this kind of structures and inspected experimentally by use of a laboratory model. The method is investigated for developing the robust damage detection technique which is less sensitive to both measurement and analytical model uncertainties. For this purpose, incorporation of the artificial immune system with weighted attributes （AISWA） method into finite element （FE） model updating is proposed and compared with other methods for exploring its effectiveness in damage identification. Based on mimicking immune recognition, noise simulation and attributes weighting, the method offers important advantages and has high success rates. Therefore, it is proposed as a suitable method for the detection of the failures in the large civil engineering structures with complicated structural geometry, such as the considered case study.
基金National Science Foundation of China(No.60 173 0 3 1)
文摘This paper presented an idea to replace the traditionally expensive parallel machines by heterogeneous cluster of workstations. To emphasise the usability of cluster of workstations platform for parallel and distributed computing, also the paper presented the status report on the effort and experiences for the implementation of a dynamic load balancing for parallel tree computation depth first search(DFS) on the cluster of a workstations project. It compared the speedup performance obtained from our platform with that obtained from the traditional one. The speedup results show that cluster of workstations can be a serious alternative to the expensive parallel machines.
文摘The detailed groundwater flow and water chemistry to illustrate landscape structure of the infertile peatless mire by using piezometers and groundwater wells were measured. The instruments were installed in lines through a small spring-fed wetland underlying little peat from the hillslope to the valley bottom in southwestern Japan. Flow net and EC data clearly indicated that the wetland was situated in a high-EC groundwater upspring area. The low-productivity graminous vegetation was related with four hydrological factors such as: (1) high water level; (2) low-EC(<25 micro S/cm) groundwater; (3) weakly upward hydraulic gradient; and (4) overflowing of negatively pressured groundwater. In other words, the “old or deep groundwater” constructed the foundation of slope-wetland, and maintained the high groundwater level. In contrast, overflowing “youthful groundwater” is supplied from head of slope-wetland preferentially through the shallow substratum. The plant communities of the peatless mire in southwestern Japan are similar to those of raised bog in northern cool temperate Japan. There have been some reports verifying that the underlying mineral substrata of such wetlands were quartzile rocks such as granite, rhyolite, chart and well-leached sand. Results showed (1) low cation availability affects the water acidity; (2) upward seepage of high-EC groundwater composed the foundation of the investigated peatless mire; and (3) the poor mineral condition seems to play a similar role to northern ombrotrophic(rain-fed) condition.
文摘Purpose: To identify a new syndrome that might occur following LASIK, and to point out causes, deferential diagnosis and the treatment of this new syndrome. Design: retrospective observational non-comparative study. Methods: 13 eyes (8 patients) had developed late onset DLK-like reaction after uneventful LASIK procedure. The patients were divided into 2 groups, group I (GI):
文摘国际新媒体联盟(New Media Consortium,简称NMC)所发布的年度地平线报告已经成为全球范围内教育信息化发展的显示器与风向标。2012年10月,北京开放大学与美国新媒体联盟签署协议,授权北京开放大学作为其在中国发行其年度报告中文版的唯一官方机构。本期学报正式刊出的2013年度地平线报告显示,未来五年内影响高等教育的六大技术为:大规模开放网络课程、平板电脑、游戏和游戏化、学习分析技术、3D打印技术、可穿戴技术。这些新技术对于我们生活中的沟通交流、获取信息、社会交往、日常学习等方面正在产生重大而深远的影响。希望本报告能够有助于国内同行及时了解国际范围内教育信息化的发展趋势、新技术应用,为促进信息技术更有效地提高教学质量服务提供有益借鉴。新媒体联盟总裁莱瑞博士(Larry Johnson)专门写信祝贺2013年度地平线报告(中文版)刊出:"北京开放大学与新媒体联盟的合作已使成千上万的中国教育界同行有机会围绕教育技术及其在大学和中小学课堂应用问题参与全球对话。北京开放大学以其在教育技术、在线学习的实践探索及开展的国际合作等方面取得的业绩成为国际地平线项目有价值的合作者。你们为地平线专题研究做出了贡献,还承担了地平线报告(中文版)的翻译出版。借助你们的帮助,许多国外同行开始了解信息技术如何在中国这一人口大国的大学和中小学得到应用;同时,也使中国教育界了解世界各国同行正在开展的信息化实践探索。"
