Phytoplankton structure in spring in the moats of Dinghai District,Zhoushan City was investigated in April 2016. Firstly,the species composition and dominant species of phytoplankton were analyzed,and then the water q...Phytoplankton structure in spring in the moats of Dinghai District,Zhoushan City was investigated in April 2016. Firstly,the species composition and dominant species of phytoplankton were analyzed,and then the water quality of the moats was evaluated by cell density,water-quality indicator species,biodiversity index method,and saprobic index method. The results show that there were 114 species of phytoplankton in the moats of Dinghai District in spring,belonging to 70 genera,38 families,and 7 phyla,of which Bacillarophyta,Chlorophyta and Cyanophyta were dominant; the main dominant species were Synedra acus,Aphanizomenon flosaquae,Microcytis flos-aquae,etc. The cell density of phytoplankton in the moats ranged from 1.07 million to 13.7 million cells/L. Shannon-Wiener diversity index,Margalef richness index,Pielou evenness index,and saprobic index averaged 0.93,2.53,0.12,and 2.61 respectively. On the whole,river water in the moats of Dinghai District was polluted seriously,but there was no obvious difference between the four rivers in water pollution.展开更多
Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation applicati...Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation application is precise object transportation.Generally,the object’s weight is unknown yet essential for both accurate control of the slave robot and intuitive perception of the human operator.However,due to high cost and limited installation space,it is unreliable to employ a force sensor to directly measure the weight.Therefore,in this paper,a control scheme free of force sensor is proposed for teleoperation robots to transfer a weight-unknown object accurately.In this scheme,the workspace mapping between master and slave robot is firstly established,based on which,the operator can generate command trajectory on-line by operating the master robot.Then,a slave controller is designed to follow the master command closely and estimate the object’s weight rapidly,accurately and robust to unmodeled uncertainties.Finally,for the sake of telepresence,a master controller is designed to generate force feedback to reproduce the estimated weight of the object.In the end,comparative experiments show that the proposed scheme can achieve better control accuracy and telepresence,with accurate force feedback generated in only 500 ms.展开更多
This paper presents the basis of acoustic method used for temperature field measurement of seafloor hydrothermal vent and two techniques of the parabolic interpolation and the bending compensation of propagation paths...This paper presents the basis of acoustic method used for temperature field measurement of seafloor hydrothermal vent and two techniques of the parabolic interpolation and the bending compensation of propagation paths of acoustic signal are introduced. Experimental research is performed to exactly rebuild the temperature field around hot springs on the floor of Qiezishan Lake, Yunnan, China. The accuracy of the travel time estimation has been improved based on the aforementioned technique and method. At the same time, by comparison of the results of temperature field with different means, the max absolute error, the maximum relative error and the root mean square error are given. It shows that the technique and the method presented in the paper can be applied to the temperature field measurement detector around the seafloor hydrothermal vent. It also has a good accuracy.展开更多
Proteases in male reproductive tract are considered to play key roles in fertilization processes.In contrast to mammals,there are limited data concerning crustacean sperm proteases.We previously identified a novel spe...Proteases in male reproductive tract are considered to play key roles in fertilization processes.In contrast to mammals,there are limited data concerning crustacean sperm proteases.We previously identified a novel sperm gelatinase(MSG) from Macrobrachium rosenbergii that was inhibited by a male reproduction-related Kazal-type protease inhibitor(MRPINK) specifically.In the present study,MSG was found to be distributed on the vas deferens and terminal ampullae by Western blot.Immunohistochemical analyses revealed that MSG was expressed in secretory epithelial cells and sperm distributed mainly at the base zone.RNA interference(RNAi) mediated knock-down of MSG resulted in a marked loss of sperm gelatinolytic activity.Taken together,the results show that MSG is closely linked to and probably involved in the fertilization process.展开更多
Hydrodynamic, physical, and biochemical processes in the Baiyangdian Lake water environment were analyzed comprehensively. An eutrophication eco- dynamics model including the effects of reed resistance on flow was cou...Hydrodynamic, physical, and biochemical processes in the Baiyangdian Lake water environment were analyzed comprehensively. An eutrophication eco- dynamics model including the effects of reed resistance on flow was coupled with the hydrodynamics governing equations. An improvement on the Water Quality Analysis Simulation Program （WASP, a modeling system intro- duced by the US Environmental Protection Agency） is established, which uses the zooplankton kinetic equation. The model simulates water quality constituents associated with eutrophication in the lake, including phytoplankton, zooplankton, nitrogen, phosphorus, dissolved oxygen, and others. Various kinetic coefficients were calibrated using measured data or information from relevant literature, to study eutrophication in the lake. The values calculated by the calibrated model agree well with field data, including ammonia nitrogen, total nitrogen, total phosphorus and dissolved oxygen. Changes related to nutrition and dissolved oxygen during the processes were simulated. The present model describes the temporal variation of water quality in Baiyangdian Lake with reasonable accuracy. Deviations between model-simulated and observed values are discussed. As an ideal tool for environmental management of the lake, this model can be used to predict its water quality, and be used in research to examine the eutrophication process.展开更多
基金Supported by Natural Science Foundation for Young Scholars of Zhejiang Province,China(LQ15C030001)Scientific Research Funds of Zhejiang Ocean University(21035012413)+1 种基金Xinmiao Talents Project of Zhejiang Province,China(2016R411056)Science and Technology Innovation Project of Zhejiang Ocean University(xj201511)
文摘Phytoplankton structure in spring in the moats of Dinghai District,Zhoushan City was investigated in April 2016. Firstly,the species composition and dominant species of phytoplankton were analyzed,and then the water quality of the moats was evaluated by cell density,water-quality indicator species,biodiversity index method,and saprobic index method. The results show that there were 114 species of phytoplankton in the moats of Dinghai District in spring,belonging to 70 genera,38 families,and 7 phyla,of which Bacillarophyta,Chlorophyta and Cyanophyta were dominant; the main dominant species were Synedra acus,Aphanizomenon flosaquae,Microcytis flos-aquae,etc. The cell density of phytoplankton in the moats ranged from 1.07 million to 13.7 million cells/L. Shannon-Wiener diversity index,Margalef richness index,Pielou evenness index,and saprobic index averaged 0.93,2.53,0.12,and 2.61 respectively. On the whole,river water in the moats of Dinghai District was polluted seriously,but there was no obvious difference between the four rivers in water pollution.
基金supported in part by the National Natural Science Foundation of China(52075476,92048302)Key R&D Program of Zhejiang Province(2021C03013)。
文摘Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation application is precise object transportation.Generally,the object’s weight is unknown yet essential for both accurate control of the slave robot and intuitive perception of the human operator.However,due to high cost and limited installation space,it is unreliable to employ a force sensor to directly measure the weight.Therefore,in this paper,a control scheme free of force sensor is proposed for teleoperation robots to transfer a weight-unknown object accurately.In this scheme,the workspace mapping between master and slave robot is firstly established,based on which,the operator can generate command trajectory on-line by operating the master robot.Then,a slave controller is designed to follow the master command closely and estimate the object’s weight rapidly,accurately and robust to unmodeled uncertainties.Finally,for the sake of telepresence,a master controller is designed to generate force feedback to reproduce the estimated weight of the object.In the end,comparative experiments show that the proposed scheme can achieve better control accuracy and telepresence,with accurate force feedback generated in only 500 ms.
基金supported by the National Science and Technology Support Program of China(Grant No.2012BAB09B02)Zhejiang Key Discipline of Marine Technology and Systems(Grant No.20120109)the National High Technology Research and Development Program of China(863Program,Grant No.2007AA09Z213)
文摘This paper presents the basis of acoustic method used for temperature field measurement of seafloor hydrothermal vent and two techniques of the parabolic interpolation and the bending compensation of propagation paths of acoustic signal are introduced. Experimental research is performed to exactly rebuild the temperature field around hot springs on the floor of Qiezishan Lake, Yunnan, China. The accuracy of the travel time estimation has been improved based on the aforementioned technique and method. At the same time, by comparison of the results of temperature field with different means, the max absolute error, the maximum relative error and the root mean square error are given. It shows that the technique and the method presented in the paper can be applied to the temperature field measurement detector around the seafloor hydrothermal vent. It also has a good accuracy.
基金supported by the National Basic Research Program of China (2010CB833803)National Natural Science Foundation of China(40730212,30901093)Zhejiang Marine Biotechnology Innovation Team (2010R50029,2012R10029-14)
文摘Proteases in male reproductive tract are considered to play key roles in fertilization processes.In contrast to mammals,there are limited data concerning crustacean sperm proteases.We previously identified a novel sperm gelatinase(MSG) from Macrobrachium rosenbergii that was inhibited by a male reproduction-related Kazal-type protease inhibitor(MRPINK) specifically.In the present study,MSG was found to be distributed on the vas deferens and terminal ampullae by Western blot.Immunohistochemical analyses revealed that MSG was expressed in secretory epithelial cells and sperm distributed mainly at the base zone.RNA interference(RNAi) mediated knock-down of MSG resulted in a marked loss of sperm gelatinolytic activity.Taken together,the results show that MSG is closely linked to and probably involved in the fertilization process.
文摘Hydrodynamic, physical, and biochemical processes in the Baiyangdian Lake water environment were analyzed comprehensively. An eutrophication eco- dynamics model including the effects of reed resistance on flow was coupled with the hydrodynamics governing equations. An improvement on the Water Quality Analysis Simulation Program （WASP, a modeling system intro- duced by the US Environmental Protection Agency） is established, which uses the zooplankton kinetic equation. The model simulates water quality constituents associated with eutrophication in the lake, including phytoplankton, zooplankton, nitrogen, phosphorus, dissolved oxygen, and others. Various kinetic coefficients were calibrated using measured data or information from relevant literature, to study eutrophication in the lake. The values calculated by the calibrated model agree well with field data, including ammonia nitrogen, total nitrogen, total phosphorus and dissolved oxygen. Changes related to nutrition and dissolved oxygen during the processes were simulated. The present model describes the temporal variation of water quality in Baiyangdian Lake with reasonable accuracy. Deviations between model-simulated and observed values are discussed. As an ideal tool for environmental management of the lake, this model can be used to predict its water quality, and be used in research to examine the eutrophication process.
