In the present study, an existing three-dimensional finite volume computational ocean model （FVCOM） was refined and configured including an algorithm for computing the power density and mean power density at Qiongzh...In the present study, an existing three-dimensional finite volume computational ocean model （FVCOM） was refined and configured including an algorithm for computing the power density and mean power density at Qiongzhou Strait of China. The refined model was validated with the measured tidal levels and tidal currents at different gauging stations. The model results are in reasonable agreement with the measured data. Based on the modeling results, we assess the resource of the tidal stream energy in the Qiongzhou Strait and discuss the temporal and the spatial distribution of the tidal current energy there. The conclusion is extracted： the higher power density occurs in the middle area of the strait, and lower at both sides. Characteristics of power density such as the maximum possibility speed, maximum power density during the spring tide period and the neap tide period, have the similar distribution. The southeast part and central area of the strait are of rich tidal current energy, where the maximum possibility speed can reach to 4.6 m/s, and the maximum power density of the spring tide period and the neap tide period can reach 5 996 and 467 W/mz separately in the surface layer The annual mean power density can reach 819 W/m2. Statistical length of accumulative time of the velocity exceeding 0.7 m/s is about 4 717 h at local point during a year. The total theoretical tidal current energy resource is approximately 189.55 MW and the available exploited energy on present technology condition is 249, 20.2 and 263 GW/a separately by using the methods FLUX, FARM and GC in the Qiongzhou Strait.展开更多
The Shacheng Bay （SCB） is one of the most complex coastal bays in southeast China and due to the fact of complicated geometry and dynamic coastal processes, it is considered as a challenging area for the nu- merical...The Shacheng Bay （SCB） is one of the most complex coastal bays in southeast China and due to the fact of complicated geometry and dynamic coastal processes, it is considered as a challenging area for the nu- merical simulation of its hydrodynamic characteristics. The most advanced finite volume ocean model, fi- nite-volume coastal ocean model （FVCOM）, has adopted to simulate this hydrodynamic system, where tidal currents, tidal residual current and dye diffusion processes were studied and analyzed quantitatively. The validation of this numerical model matches well with various observation data, including elevation and current data. The misfit of a tidal elevation has a relative standard error of 3.66% and 4.67% for M2 and S2 tide components. The current validation shows a good match with an average error of 10 cm/s and 8° in the speed major axis and its direction respectively between the simulation and the measurement. This proves the robustness and reliability of this model. It is also found that the cape effect is significant and important in this system. The dye diffusion simulations show a 53 d flushing period for the whole inner bay waterbody. The results are of its first kind for understanding the hydrodynamic system in the SCB and they can provide helnful and trustful scientific information for others.展开更多
In consideration of the resource wasted by unreasonable layout scheme of tidal current turbines, which would influence the ratio of cost and power output, particle swarm optimization algorithm is introduced and improv...In consideration of the resource wasted by unreasonable layout scheme of tidal current turbines, which would influence the ratio of cost and power output, particle swarm optimization algorithm is introduced and improved in the paper. In order to solve the problem of optimal array of tidal turbines, the discrete particle swarm optimization(DPSO) algorithm has been performed by re-defining the updating strategies of particles’ velocity and position. This paper analyzes the optimization problem of micrositing of tidal current turbines by adjusting each turbine’s position,where the maximum value of total electric power is obtained at the maximum speed in the flood tide and ebb tide.Firstly, the best installed turbine number is generated by maximizing the output energy in the given tidal farm by the Farm/Flux and empirical method. Secondly, considering the wake effect, the reasonable distance between turbines,and the tidal velocities influencing factors in the tidal farm, Jensen wake model and elliptic distribution model are selected for the turbines’ total generating capacity calculation at the maximum speed in the flood tide and ebb tide.Finally, the total generating capacity, regarded as objective function, is calculated in the final simulation, thus the DPSO could guide the individuals to the feasible area and optimal position. The results have been concluded that the optimization algorithm, which increased 6.19% more recourse output than experience method, can be thought as a good tool for engineering design of tidal energy demonstration.展开更多
Myocardial injury is one of the most common comorbidity in SARS-CoV-2 infected patients,and has poor prognosis.However,the incidence of myocardial injury in patients with SARS-CoV-2 infection has not been sufficiently...Myocardial injury is one of the most common comorbidity in SARS-CoV-2 infected patients,and has poor prognosis.However,the incidence of myocardial injury in patients with SARS-CoV-2 infection has not been sufficiently investigated during the Omicron wave.We conducted a retrospective study of 2690 patients with confirmed SARS-CoV-2 Omicron infection from Tongji Hospital.The results indicated that the myocardial injury accounted for 30.8%of the total patients with SARS-CoV-2 infection and was associated with higher in-hospital mortality than those without injury before and after propensity score matching(PSM)[adjusted hazard ratio(HR),10.61;95%confidence interval(CI),7.76–14.51;P<0.001;adjusted HR,2.70;95%CI,1.86–3.93;P<0.001;respectively].Further,the levels of cytokines(IL-1β,IL-6,IL-10,and TNF-α)in patients with myocardial injury were higher than those without injury,and the higher levels of cytokines in the myocardial injury group were associated with increased mortality.Administration of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers(ACEI/ARB)could significantly reduce the mortality in patients with myocardial injury(adjusted HR,0.52;95%CI,0.38–0.71;P<0.001).Additionally,the level of angiotensin II increased in patients with SARS-CoV-2 infection was even higher in myocardial injury group compared to those without injury.Collectively,the study summarized the clinical characteristic and outcome of SARS-CoV-2 infected patients with myocardial injury during the Omicron wave in China,and validated the protective role of ACEI/ARB in improving the survival of those with myocardial injury.展开更多
An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region name...An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region named PuHu Channel between Putuo Island and Hulu Island.The model was calibrated with several measurements in the channel,and the model perform-ance was validated.An examination of the spatial and temporal distributions of tidal energy resources based on the numerical simula-tion revealed that the greatest power density of tidal energy during spring tide is 3.6kWm^(−2)at the northern area of the channel.Two parameters were introduced to characterize the generation duration of the tidal array that causes the temporal variation of tidal current energy.The annual average available energy in the channel was found to be approximately 2.6MW.The annual generating hours at rated power was found to be 1800 h when the installed capacity of tidal array is approximately 12MW.A site for the tidal array with 25 turbines was selected,and the layout of the array was configured based on the EMEC specifications.Hydrodynamic influence due to the deployment of the tidal array was simulated by the modified FVCOM model.The simulation showed that the tidal level did not significantly change because of the operation of the tidal array.The velocity reduction covered a 2km^(2)area of the downstream the tidal array,with a maximum velocity reduction of 8cms−1 at mid-flood tide,whereas the streamwise velocity on both sides of the farm increased slightly.展开更多
基金The Chinese Marine Renewable Energy Special Fund under contract Nos GHME2012ZC05 and GHME2013ZC03
文摘In the present study, an existing three-dimensional finite volume computational ocean model （FVCOM） was refined and configured including an algorithm for computing the power density and mean power density at Qiongzhou Strait of China. The refined model was validated with the measured tidal levels and tidal currents at different gauging stations. The model results are in reasonable agreement with the measured data. Based on the modeling results, we assess the resource of the tidal stream energy in the Qiongzhou Strait and discuss the temporal and the spatial distribution of the tidal current energy there. The conclusion is extracted： the higher power density occurs in the middle area of the strait, and lower at both sides. Characteristics of power density such as the maximum possibility speed, maximum power density during the spring tide period and the neap tide period, have the similar distribution. The southeast part and central area of the strait are of rich tidal current energy, where the maximum possibility speed can reach to 4.6 m/s, and the maximum power density of the spring tide period and the neap tide period can reach 5 996 and 467 W/mz separately in the surface layer The annual mean power density can reach 819 W/m2. Statistical length of accumulative time of the velocity exceeding 0.7 m/s is about 4 717 h at local point during a year. The total theoretical tidal current energy resource is approximately 189.55 MW and the available exploited energy on present technology condition is 249, 20.2 and 263 GW/a separately by using the methods FLUX, FARM and GC in the Qiongzhou Strait.
基金The National Marine Renewable Energy Programs of China under contract Nos GHME2011ZC03,GHME2011GD01,GHME2012ZC02,GHME2012ZC03,GHME2012ZC05 and GHME2013ZC01the National Natural Science Foundation of China under contract No.41406011+5 种基金the Doctoral Fund of Ministry of Education of China under contract No.20120132120016the Shandong Province Natural Science Foundation of China under contract No.ZR2012DQ008the Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA11010201the Open Laboratory Fund of North China Sea Branch of State Oceanic Administration under contract No.2012012the Fundamental Research Funds for the Central Universities under contract No.201262004the Public Science and Technology Research Funds Projects of Ocean under contract No.201305030
文摘The Shacheng Bay （SCB） is one of the most complex coastal bays in southeast China and due to the fact of complicated geometry and dynamic coastal processes, it is considered as a challenging area for the nu- merical simulation of its hydrodynamic characteristics. The most advanced finite volume ocean model, fi- nite-volume coastal ocean model （FVCOM）, has adopted to simulate this hydrodynamic system, where tidal currents, tidal residual current and dye diffusion processes were studied and analyzed quantitatively. The validation of this numerical model matches well with various observation data, including elevation and current data. The misfit of a tidal elevation has a relative standard error of 3.66% and 4.67% for M2 and S2 tide components. The current validation shows a good match with an average error of 10 cm/s and 8° in the speed major axis and its direction respectively between the simulation and the measurement. This proves the robustness and reliability of this model. It is also found that the cape effect is significant and important in this system. The dye diffusion simulations show a 53 d flushing period for the whole inner bay waterbody. The results are of its first kind for understanding the hydrodynamic system in the SCB and they can provide helnful and trustful scientific information for others.
基金financially supported by the Marine Renewable Energy Funding Project(Grant Nos.GHME2017ZC01 and GHME2016ZC04)the National Natural Science Foundation of China(Grant Nos.5171101175 and 51679125)+1 种基金Tianjin Municipal Natural Science Foundation(Grant No.16JCYBJC20600)Technology Innovation Fund of National Ocean Technology Center(Grant No.F2180Z002)
文摘In consideration of the resource wasted by unreasonable layout scheme of tidal current turbines, which would influence the ratio of cost and power output, particle swarm optimization algorithm is introduced and improved in the paper. In order to solve the problem of optimal array of tidal turbines, the discrete particle swarm optimization(DPSO) algorithm has been performed by re-defining the updating strategies of particles’ velocity and position. This paper analyzes the optimization problem of micrositing of tidal current turbines by adjusting each turbine’s position,where the maximum value of total electric power is obtained at the maximum speed in the flood tide and ebb tide.Firstly, the best installed turbine number is generated by maximizing the output energy in the given tidal farm by the Farm/Flux and empirical method. Secondly, considering the wake effect, the reasonable distance between turbines,and the tidal velocities influencing factors in the tidal farm, Jensen wake model and elliptic distribution model are selected for the turbines’ total generating capacity calculation at the maximum speed in the flood tide and ebb tide.Finally, the total generating capacity, regarded as objective function, is calculated in the final simulation, thus the DPSO could guide the individuals to the feasible area and optimal position. The results have been concluded that the optimization algorithm, which increased 6.19% more recourse output than experience method, can be thought as a good tool for engineering design of tidal energy demonstration.
基金grant of National Key Research and Development Program of China(2022YFC3400700)National Natural Science Foundation of China(Nos.82241034,82370397,31971358,U22A20266 and C-0052)+2 种基金Top-Notch Talent Program of Hubei Province and Tongji Hospital(No.2021YBJRC005)Hubei Provincial Key Research and Developmental Program(2022BCA037)Hubei Provincial Natural Science Foundation of China(2017CFB536).
文摘Myocardial injury is one of the most common comorbidity in SARS-CoV-2 infected patients,and has poor prognosis.However,the incidence of myocardial injury in patients with SARS-CoV-2 infection has not been sufficiently investigated during the Omicron wave.We conducted a retrospective study of 2690 patients with confirmed SARS-CoV-2 Omicron infection from Tongji Hospital.The results indicated that the myocardial injury accounted for 30.8%of the total patients with SARS-CoV-2 infection and was associated with higher in-hospital mortality than those without injury before and after propensity score matching(PSM)[adjusted hazard ratio(HR),10.61;95%confidence interval(CI),7.76–14.51;P<0.001;adjusted HR,2.70;95%CI,1.86–3.93;P<0.001;respectively].Further,the levels of cytokines(IL-1β,IL-6,IL-10,and TNF-α)in patients with myocardial injury were higher than those without injury,and the higher levels of cytokines in the myocardial injury group were associated with increased mortality.Administration of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers(ACEI/ARB)could significantly reduce the mortality in patients with myocardial injury(adjusted HR,0.52;95%CI,0.38–0.71;P<0.001).Additionally,the level of angiotensin II increased in patients with SARS-CoV-2 infection was even higher in myocardial injury group compared to those without injury.Collectively,the study summarized the clinical characteristic and outcome of SARS-CoV-2 infected patients with myocardial injury during the Omicron wave in China,and validated the protective role of ACEI/ARB in improving the survival of those with myocardial injury.
基金This work was supported by the National Key R&D Program of China(Nos.2019YFE0102500,2019YFB1504401,2019YFE0102500 and 2016YFC1401800).The au-thors would like to thank the FVCOM Development Group for their modeling support.
文摘An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region named PuHu Channel between Putuo Island and Hulu Island.The model was calibrated with several measurements in the channel,and the model perform-ance was validated.An examination of the spatial and temporal distributions of tidal energy resources based on the numerical simula-tion revealed that the greatest power density of tidal energy during spring tide is 3.6kWm^(−2)at the northern area of the channel.Two parameters were introduced to characterize the generation duration of the tidal array that causes the temporal variation of tidal current energy.The annual average available energy in the channel was found to be approximately 2.6MW.The annual generating hours at rated power was found to be 1800 h when the installed capacity of tidal array is approximately 12MW.A site for the tidal array with 25 turbines was selected,and the layout of the array was configured based on the EMEC specifications.Hydrodynamic influence due to the deployment of the tidal array was simulated by the modified FVCOM model.The simulation showed that the tidal level did not significantly change because of the operation of the tidal array.The velocity reduction covered a 2km^(2)area of the downstream the tidal array,with a maximum velocity reduction of 8cms−1 at mid-flood tide,whereas the streamwise velocity on both sides of the farm increased slightly.
