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Effects of residual chlorine on the mortality, grazing and respiration of Labidocera euchaeta (Copepoda)

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Acta oceanologica Sinica 2011年第2期30卷 96-102页

作者： MA Zengling LIN Hongping GU Xiaolian XU Zhaoli Key and Open Laboratory of Marine and Estuary Fisheries （Ministry of Agriculture） East ChinaSea Fisheries Research Institute Chinese Academy of Fisheries Science Shanghai 200090 China Institute of Life Science and Technology Zhanjiang Normal University Zhanjiang 524048 China

In this study,the authors investigated the effects of residual chlorine on mortality,grazing and respiration of Labidocera euchaeta in *** grazing rate was evaluated by subtraction method of food concentration and respiration rate was measured using oxygen *** was found that the lethal effect of residual chlorine on *** increased with enhanced concentration and prolonged *** medium lethal concentration （LC 50 ） of chlorine for *** in 2. h was about 0.58 mg/L and the safe concentration was about 0.2. mg/***,the grazing and respiration of *** decreased by 32.6% and 18.9% when exposed to 0.2.mg/L residual chlorine for 4 *** indicated that the physiological activities of zooplankton could be suppressed by the residual chlorine less than the safety ***,both survival and physiological activities of the organisms living in the thermal （nuclear） power plant discharging waters should be considered when carrying out the ecological risks assessment.

关键词： copepod grazing Labidocera euchaeta residual chlorine respiration zooplankton

Boundary conditions for the bending of a piezoelectric beam

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2.& ZHAO BaoSheng3 1 College of Science, china Agricultural university, Beijing 100083, china 2.College of Engineering, ocean university of china, Qingdao 2.6071, china 3 School of Mechanical Engineering, university of Science and Technology Liaoning, Anshan 114044, china 1. College of Science China Agricultural University Beijing 100083 China 2. College of Engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical Engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Mixed boundary conditions for piezoelectric plates

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2.&ZHAO BaoSheng 3 1College of Science,china Agricultural university,Beijing 100083,china 2.ollege of Engineering,ocean university of china,Qingdao 2.6071,china 3 School of Mechanical Engineering,university of Science and Technology of Liaoning,Anshan 114044,china College of Science China Agricultural University Beijing 100083 China College of Engineering Ocean University of China Qingdao 266071 China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

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Acta oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang College of Marine Life Science Ocean University of China Qingdao 266003 China College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in china＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2.0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Seabed Classification Using BP Neural Network Based on GA

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Acta oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS Engineering Research Center, Wuhan university, Wuhan 430079, china. 2. Presidential Secretariat, Wuhan university, Wuhan 430079, china Wuhan Univ GPS Engn Res Ctr Wuhan 430079 Peoples R China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Meso-scale circulation at the intermediate-depth east of Mindanao observed by Argo profiling floats

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Science china Earth Sciences 2010年第3期53卷 432-440页

作者： ZHOU Hui1, YUAN DongLiang1, GUO PeiFang2. SHI MaoChong2.& ZHANG QiLong 1 Key Laboratory of ocean Circulation and Wave Studies, Chinese Academy of Sciences, Qingdao 2.6071, china 2.Physical oceanography Laboratory, ocean university of china, Qingdao 2.6100, china 1. Key Laboratory of ocean Circulation and Wave Studies Chinese Academy of Sciences Qingdao 266071 China2. Physical Oceanography Laboratory Ocean University of China Qingdao 266100 China

The meso-scale circulation at the intermediate depth east of Mindanao is studied using Argo profiling floats observations. The trajectories and the parking-depth velocities of Argo floats show that the intermediate-depth circulation east of Mindanao contains significant meso-scale features that are highly variable both in space and in time. Both cyclonic and anticyclonic eddies at the intermediate depth (1000–2.00 m) are indicated by the trajectories east of Mindanao. The mean tangential velocities of these eddies are about 10 cm/s at 2.00 m and over 2. cm/s at 1000 m, which indicates that the geostrophic calculation may contain large errors due to the vigorous eddy activity at the reference levels. The analyses also suggest that these eddies might play an important role in mass and vorticity balances of the intermediate-depth circulation east of Mindanao.

关键词： Mindanao Current intermediate-depth circulation meso-scale eddy Argo profiling float

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基于因式分解的防止欺诈的多秘密分享方案

铁道学报 2004年第4期26卷 79-81页

作者：甘元驹曹刚湛江海洋大学信息学院广东湛江524088 中南大学信息科学与工程学院湖南长沙410075

针对现有的多秘密分享方案不能同时有效解决分发者和分享者欺诈,以及子秘密恢复时计算量大等问题,在基于求解大整数因式分解的难题上,提出了一种有效的解决方案。该方案不仅有效地解决了分发者和分享者欺诈问题,而且每个分享者只需拥有... 详细信息

针对现有的多秘密分享方案不能同时有效解决分发者和分享者欺诈,以及子秘密恢复时计算量大等问题,在基于求解大整数因式分解的难题上,提出了一种有效的解决方案。该方案不仅有效地解决了分发者和分享者欺诈问题,而且每个分享者只需拥有一个秘密份额就能和其它分享者分享多个秘密信息。与其它已有的方案相比,方案的优点在于计算量低和子秘密恢复时采用了并行算法。

关键词：密码学多秘密分享因式分解问题欺骗

Scaling of motion and governing equations for baroclinic large-scale motions in equatorial ocean

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Acta oceanologica Sinica 2000年第1期19卷 15-24页

作者： Fan Zhisong and Pu Shuzhen (1. Marine Environment College, ocean university of Qingdao, Qingdao 2.6003,{2. 2. First institute of oceanography, State oceanic Administration, Qingdao 2.6003,{2.) Marine Environment College Ocean University of Qingdao Qingdao 266003 China First Institute of oceanography State Oceanic Administration Qingdao 266003 China

An obvious characteristic of the baroclinic large-scale motions in the equatorial ocean is that the meridional scale H of motion is far smaller than the zonal scale L. The scaling of motion carefully with this striking characteristic in this paper results in two conclusions, i. e., the Coriolis terms associated with the horizontal component of the rotation vector cannot be neglected in the governing equations; and the use of the absence of heating is not suitable to the equatorial region. In this paper the equatorial β-plane nondimensional governing equations with the small parametersδ_0 andδ_1 have been Obtained.

关键词： Baroclinic large-scale motions in equatorial ocean horizontal component of rotation vector equatorial B-plane

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惊恐障碍焦虑敏感性的特征及其作用研究进展

神经疾病与精神卫生 2024年第8期24卷 584-589页

作者：何放李占江杨祥云首都医科大学附属北京安定医院、国家精神心理疾病临床医学研究中心、精神疾病诊断与治疗北京市重点实验室 100088 首都医科大学人脑保护高精尖创新中心北京100069

惊恐障碍是一种以反复出现惊恐发作为特征的急性焦虑障碍,严重影响患者的社会功能及生活质量。惊恐障碍的发病机制目前尚不明确,相关研究表明焦虑敏感性是惊恐障碍发作的易感因素,高水平的焦虑敏感性与惊恐障碍严重程度呈正相关,并导致... 详细信息

惊恐障碍是一种以反复出现惊恐发作为特征的急性焦虑障碍,严重影响患者的社会功能及生活质量。惊恐障碍的发病机制目前尚不明确,相关研究表明焦虑敏感性是惊恐障碍发作的易感因素,高水平的焦虑敏感性与惊恐障碍严重程度呈正相关,并导致患者预后不良。本文对惊恐障碍患者焦虑敏感性特征及焦虑敏感性在惊恐障碍发生、发展、干预中的作用等进行综述,以期为惊恐障碍临床诊疗提供参考依据。

关键词：惊恐障碍焦虑敏感性特征作用机制综述