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Journal of Oceanology and Limnology 2019年第5期37卷 1698-1707页

作者： LIU Qinghe ma lin LI Xinzheng Institute of Oceanology Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology (Qingdao)Qingdao 266237China

A new species belonging to the genus Haloschizopera Lang, 1944 (Copepoda, Harpacticoida, Miraciidae, Diosaccinae) was identifi ed based on the samples collected from the East China Sea, near the off shore of Zhejiang Province, East China. The new species is closely related to H . pygmaea Norman & Sccot T., 1905 and shares a combination of the following features: A1 eight-segmented;A2 exp-2 with one distal seta, exp-3 with three setae;P1 endopodal segments subequal, enp-1 not exceeding exp-2;exp-3 of P3 with one inner seta, of P4 with two inner setae. The new species is characterized by the presence of one inner seta on P2 exp-3 of both sexes. It can also be distinguished from its congeners by the characters of female: P5 exopod subcircular, endopodal lobe extending beyond half-length of exopod;genital doublesomite ornamented with three dorsolateral rows of spinules on anterior part.

关键词： meiobenthos new species taxonomy species group

A Resource Scheduling Scheme for Spectrum Aggregation in Cognitive Radio Based Heterogeneous Networks

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China Communications 2015年第9期12卷 100-111页

作者： Fu Yunhai ma lin Xu Yubin Harbin Institute of Technology Communication Research Center Key Laboratory of Police Wireless Digital Communication Ministry of Public Security

In spectrum aggregation(SA), two or more component carriers(CCs) of different bandwidths in different bands can be aggregated to support wider transmission bandwidth. The current resource scheduling schemes for spectrum aggregation are not optimal or suitable for CR based heterogeneous networks(Het Nets). Consequently, the authors propose a novel resource scheduling scheme for spectrum aggregation in CR based Het Nets, termed as cognitive radio based resource scheduling(CR-RS) scheme. CR-RS has a three-level structure. Under a dynamic traffic model, an equivalent throughput of the CCs based on the knowledge of primary users(PUs) is given. On this basis, the CR users data transmission time of each CC is equal in CR-RS. The simulation results show that CR-RS has the better performance than the current resource scheduling schemes in the CR based Het Nets. Meanwhile, CR-RS is also effective in other spectrum aggregation systems which are not CR based HetNets.

关键词： CR-RS spectrum aggregation resource scheduling cognitive radio heterogeneous networks

地方认同视角下城市边缘传统集市的转型及意义重构

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云南地理环境研究 2024年第1期36卷 28-37页

作者：李晗马玲华红莲云南师范大学地理学部云南昆明650500

以呈贡集市龙街为例,在对龙街内及附近的居民进行地方依恋和地方认同的问卷调查和深度访谈的基础上,运用SPSS 26.0统计分析软件对收集的100份问卷进行定量分析。结果表明:(1)龙街的地方依恋和地方认同之间关系显著且为正相关,地方依恋... 详细信息

以呈贡集市龙街为例,在对龙街内及附近的居民进行地方依恋和地方认同的问卷调查和深度访谈的基础上,运用SPSS 26.0统计分析软件对收集的100份问卷进行定量分析。结果表明:(1)龙街的地方依恋和地方认同之间关系显著且为正相关,地方依恋程度越高,地方认同的程度就越高。(2)年龄、离地时间和月收入状况对居民地方认同的影响显著,3个要素共同指向居民治愈性的需求。(3)龙街的功能重构表现在经济功能逐渐衰减,而文化功能却不断增强,因为其满足了城市居民从地方性中获得治愈的需求,才能在城市化进程中长青。该研究对城镇化与城乡一体化、服务三农、乡村振兴等具有一定的现实意义。

关键词：传统集市城市化地方认同城市边缘呈贡龙街

Research on Low Energy Consumption Distributed Fault Detection Mechanism in Wireless Sensor Network

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China Communications 2019年第3期16卷 179-189页

作者： Shuang Jia lin ma Danyang Qin School of Electronics and Information Engineering Harbin Institute of Technology Key Laboratory of Electronics Engineering College of Heilongjiang Province Heilongjiang University

Wireless sensor network is an important technical support for ubiquitous communication. For the serious impacts of network failure caused by the unbalanced energy consumption of sensor nodes, hardware failure and attacker intrusion on data transmission, a low energy consumption distributed fault detection mechanism in wireless sensor network(LEFD) is proposed in this paper. Firstly, the time correlation information of nodes is used to detect fault nodes in LEFD, and then the spatial correlation information is adopted to detect the remaining fault nodes, so as to check the states of nodes comprehensively and improve the efficiency of data transmission. In addition, the nodes do not need to exchange information with their neighbor nodes in the initial detection process since LEFD adopts the data sensed by node itself to detect some types of faults, thus reducing the energy consumption of nodes effectively. Finally, LEFD also considers the nodes that may have transient faults. Performance analysis and simulation results show that the proposed detection mechanism can improve the transmission performance and reduce the energy consumption of network effectively.

关键词： wireless sensor network low energy consumption fault detection detection accuracy

Energy Efficient Access Point Selection and Signal Projection for Accurate Indoor Positioning

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China Communications 2012年第2期9卷 52-65页

作者： Deng Zhian Xu Yubin ma lin School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150080P.R.China

We propose a method to improve positioning accuracy while reducing energy consumption in an indoor Wireless Local Area Network(WLAN) ***,we intelligently and jointly select the subset of Access Points(APs) used in positioning via maximum Mutual Information(MMI) ***,we propose Orthogonal Locality Preserving Projection(OLPP) to reduce the redundancy among selected *** effectively extracts the intrinsic location features in situations where previous linear signal projection techniques failed to do,while maintaining computational ***,we show that the combination of AP selection and OLPP simultaneously exploits their complementary advantages while avoiding the *** results indicate that,compared with the widely used weighted K-nearest neighbor and maximum likelihood estimation method,the proposed method leads to 21.8%(0.49 m) positioning accuracy improvement,while decreasing the computation cost by 65.4%.

关键词： indoor positioning energy efficientcomputing WLAN maximum mutual information orthogonal locality preserving projection

玉米苞叶组织细胞结构生物质碳的制备及显微结构的研究

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电子显微学报 2024年第3期43卷 339-345页

作者：周晓亮马林杨一君余宇张致远罗马曾祥昇严铮洸北京交通大学物理科学与工程学院北京100044 北京工业大学材料学部北京100124

采用一步热解法,使用常见的玉米果穗苞叶为原料,制备了保留玉米苞叶组织细胞结构的生物质碳膜,采用扫描电镜,透射电镜等技术手段对样品的形貌和结构进行了表征,样品表面有明显的维管束以及大量的气孔的存在。不添加任何导电剂和添加剂,... 详细信息

采用一步热解法,使用常见的玉米果穗苞叶为原料,制备了保留玉米苞叶组织细胞结构的生物质碳膜,采用扫描电镜,透射电镜等技术手段对样品的形貌和结构进行了表征,样品表面有明显的维管束以及大量的气孔的存在。不添加任何导电剂和添加剂,热解碳膜直接作为工作电极使用,在100 ma·g^(-1)的电流密度下,200次循环后仍能获得218 mah·g^(-1)的可逆比容量。本工作在生物质废弃物利用,以及储能材料开发等方面有参考价值。

关键词：生物质细胞结构电子显微学储能

A general strategy for the reliable joining of Al/Ti dissimilar alloys via ultrasonic assisted friction stir welding

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Journal of materials Science & Technology 2019年第1期35卷 94-99页

作者： Zhongwei ma Yanye Jin Shude Ji Xiangchen Meng lin ma Qinghua Li School of Aerospace Engineering Shenyang Aerospace University

Ultrasonic assisted friction stir welding(UaFSW) was used to join 6061-T6 aluminum and Ti6Al4 V alloys.A small plunge depth endowed with the low heat input was used and the sound joints without obvious thickness reduction were achieved. A diffusion-type bonding without the intermetallic compounds layer was observed at the joint interface. The ultrasonic improved the diffusion thickness and decreased the average size of grains and titanium alloy fragments. A hook-like structure was formed at the bottom interface of the UaFSW joint, which improved the bonding length and the mechanical interlocking. The microhardness of the stir zone was increased because of the further grain refinement induced by ultrasonic. The maximum tensile strength of the UaFSW joint was 236 MPa, which reached 85% of the base6061-T6 alloy.

关键词： Friction stir welding Ultrasonic Aluminum/titanium alloys Microstructure Mechanical properties

Preparation and mechanical properties of two nickel base alloy coatings achieved by electrospark deposition

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Acta Metallurgica Sinica(English Letters) 2011年第4期24卷 309-314页

作者： Ping ZHANG lin ma Zhijie LIANG Junjun ZHAO Technology and Science Laboratory on Remanufacturing Academy of Armored Force EngineeringBeijing 100072 China Institute of Chemical Defense Engineering Beijing 102205 ChinaManuscript received 9 August 2010 in revised form 7 December 2010

Ni398 and Ni818 base alloy coatings were deposited on 1045 steel by electrospark deposition technique （ESD）. Forming properties, thickness, microhardness and wear resistance of the coatings were investigated. The chemical composition and cross- section morphology were analyzed through energy dispersive spectrum （EDS） and metalloscope. The results show that the technological parameter window of Ni398 is larger than that of Ni818 electrode. However, other properties of the Ni818 coating, such as thickness and microhardness, were better than those of the Ni398 coating. Especially the wornout volume of Ni818 coating is only 1/6 of that for 1045 steel and 1/3 for Ni398 coating. Chemical composition analysis indicated that the addition of Mo promoted grain refinement of nickel alloy. Metallographic analysis shows that the molten droplets of Ni398 coatings have an average structure thickness of 20-40 #m while the microstructure of Ni818 coatings is flat with width of 5-20 #m.

关键词： Electrospark deposition Nickel base alloy electrode Coatingproperty

DBS imaging based on Keystone transform

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Journal of Systems Engineering and Electronics 2012年第3期23卷 342-348页

作者： Jing Tian Wei Cui lin ma Siliang Wu Radar Research Institute Beijing Institute of TechnologyBeijing 100081E R.China

To correct the range walk through resolution cell in Doppler beam sharpening （DBS） imaging, a new DBS imaging algorithm based on Keystone transform is proposed. Without the exact values of the movement parameters and the look angle of the radar platform in the multi-targets environment, a linear trans- form on the received data is employed to correct different range walk values accurately under the condition of Doppler frequency ambiguity in this algorithm. This method can realize the cohe- rent integration in azimuth dimension and improve the azimuth resolution. In order to reduce the computational burden, a fast implementation of Keystone transform is used. Theoretical anal- ysis and simulation results demonstrate the effectiveness of the new algorithm. And through comparing the computational load of the fast implementation with several other algorithms, the real-time processing ability of the proposed algorithm is superior to that of other algorithms.

关键词： Doppler beam sharpening (DBS) Keystone transform range walk coherent integration.

A laser extinction based sensor for simultaneous droplet size and vapor measurement

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Particuology 2012年第1期10卷 9-16页

作者： Xueqiang Sun David J. Ewing lin ma College of Automatic Control and Mechanical Engineering Kunming University Kunming 650214 China Department of Aerospace and Ocean Engineering Virginia Tech Blacksburg VA 24063 USA

Multiphase flows involving liquid droplets in association with gas flow occur in many industrial and sci- entific applications. Recent work has demonstrated the feasibility of using optical techniques based on laser extinction to simultaneously measure vapor concentration and temperature and droplet size and loading. This work introduces the theoretical background for the optimal design of such laser extinction techniques, termed WMLE （wavelength-multiplexed laser extinction）. This paper focuses on the devel- opment of WMLE and presents a systematic methodology to guide the selection of suitable wavelengths and optimize the performance of WMLE for specific applications. WMLE utilizing wavelengths from 0.5 to 10 ixm is illustrated for droplet size and vapor concentration measurements in an example of water spray, and is found to enable unique and sensitive Sauter mean diameter measurement in the range of ~1-15 ~m along with accurate vapor detection. A vapor detection strategy based on differential absorp- tion is developed to extend accurate measurement to a significantly wider range of droplet loading and vapor concentration as compared to strategies based on direct fixed-wavelength absorption. Expected performance of the sensor is modeled for an evaporating spray. This work is expected to lay the ground- work for implementing optical sensors based on WMLE in a variety of research and industrial applications involving multi-phase flows.

关键词： Wavelength-multiplexed laser extinctionDropletMeasurementLaserExtinctionAbsorptionSpectroscopy