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浏览/检索结果: 共5条，第1-5条 帮助 已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Higher-order normal approximation approach for highly reliable system assessment 期刊论文 IISE TRANSACTIONS, 2019, 页码: 13 作者:  Li, Zhaohui;  Yu, Dan;  Liu, Jian;  Hu, Qingpei 收藏  |  浏览/下载：45/0  |  提交时间：2020/01/10 System reliability assessment  highly reliable system  Winterbottom-extended Cornish-Fisher expansion  reliability-based expansion  log-location-scale family   食用蔬菜能吸收和积累微塑料 期刊论文 科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934 作者:  李连祯;  周倩;  尹娜;  涂晨;  骆永明 收藏  |  浏览/下载：63/0  |  提交时间：2020/06/17 微塑料  生菜  聚苯乙烯微球  吸收  积累  健康风险  microplastics  lettuce  polystyrene microbeads  uptake  accumulation  human health risk  Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.   Highly reliable wavelength-reuse wavelength-division multiplexing semipassive optical access network architecture with double cover area and high network capacity 期刊论文 INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, 2015, 卷号: 28, 页码: 1017-1029 作者:  Gong, Yan[1];  Gan, Chaoqin[2];  Wu, Chenwei[3] 收藏  |  浏览/下载：7/0  |  提交时间：2019/04/26 wavelength reuse  highly reliable WDM semipassive optical access network  ring topology  system capacity  cover area   Miniature field bus data recorder (EI CONFERENCE) 会议论文 2010 WASE International Conference on Information Engineering, ICIE 2010, August 14, 2010 - August 15, 2010, Beidaihe, Hebei, China Chen C.-Q.; Ji Y. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 The common bus on bus control is RS232. With the development of field bus technology  field bus technology is widely used in data recorder. How to real time record the data of field bus in the experiment and provide the test data for process reconstruction is a very important problem. This paper introduces a kind of data acquisition and storage based on field bus. Its core design is C8051F040 microprocessor and SJA1000  a widely used field bus controller. This paper presents the basic constitution of this field bus data recorder and set forth its hardware and software. This field bus data recorder field bus real-time gathers the information and storage data on the CF card. The result of the experiment shows the system is highly reliable for data acquisition and storage  which should have abroad application prospect for data record experiment. 2010 IEEE.   Design of CAN bus application layer protocol for aerocraft control system (EI CONFERENCE) 会议论文 2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China Zhang H.; Jia H.; Zhang Y.; Zhang W. 收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25 A special Controller Area Network (CAN) bus application layer protocol is designed for the highly reliable communication of microcomputer-based systems in aerocraft control system by analyzing the practical time sequence of data transmission  data priority  data type and data function etc in this paper. Identifier distribution  data storage form  data type  data exchange method and fault handling mechanism of the application layer protocol are specified in detail in the background of a real aerocraft control system. At last a simulation platform based on CAN bus for aerocraft control system is built to validate the design. Experimental results show that this application layer protocol meets the requirements of data transmission reliability  real-time and high efficiency. The bus load rate is low and there is great room for expansion. 2010 IEEE.