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Simulation of charge-exchange induced NBI losses on EAST
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作者 Zhanhong LIN Feng WANG +3 位作者 Ming XU Chaofeng SANG Chen ZHANG Zhengxiong WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期133-147,共15页
The neutral beam injection is widely adopted in tokamaks as a key heating tool,playing a crucial role in generating burning plasmas.However,the loss of beam ions can damage the first wall and reduce the heating effici... The neutral beam injection is widely adopted in tokamaks as a key heating tool,playing a crucial role in generating burning plasmas.However,the loss of beam ions can damage the first wall and reduce the heating efficiency,resulting in failure to maintain steady-state conditions.In this work,the effect of neutral particles in the edge on fast ions generated by NBI in the Experimental Advanced Superconducting Tokamak(EAST)device is studied using the particle tracer code(PTC).The poloidal distribution of neutral particles is calculated by edge plasma simulation code SOLPS-ITER.In this simulation,four beam lines in EAST are considered:co-current tangential(co-tang),co-current perpendicular(co-perp),counter-current tangential(ctr-tang)and counter-current perpendicular(ctr-perp).It is shown that,in the absence of neutral particles,the loss fraction of ctr-injection is considerably higher than that of the co-injection.When considering the neutral particles,it is found that the ctr-perp injection demonstrates a significant variation in particles loss fraction(ranging from 18.56%to 25.42%)compared to the other three injection configurations.In terms of the loss fraction induced by neutral particles,ctr-injection exceeds co-injection,and perpendicular configuration exceeds tangential configuration.Furthermore,the difference of charge exchange ratios of three different energy(full energy,half energy,one third energy)of the four injections can be attributed to variations in the poloidal trajectories associated with each of these injections.Moreover,approximately half of fast ions which undergo neutralization directly lose to the first wall while the rest re-enter the bulk plasma and re-ionize.Except for the ctr-tang injection,the reionization ions from the other three injections exhibit effective confinement. 展开更多
关键词 NBI charge exchange fast ion loss
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Repeated pregnancy losses with multiple aneuploidies and major genomic imbalance:A case report
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作者 Shailesh Pande Shiny Babu +1 位作者 Harshavardhan Gawde Neha Minde 《Asian pacific Journal of Reproduction》 CAS 2024年第3期143-146,共4页
Rationale:If one of the partners is having balanced autosomal translocation,it is usually observed that the offspring inherit either normal chromosomes,balanced translocation identical to one of the parent or unbalanc... Rationale:If one of the partners is having balanced autosomal translocation,it is usually observed that the offspring inherit either normal chromosomes,balanced translocation identical to one of the parent or unbalanced chromosomal rearrangements of the same parental chromosome having translocation.Concern:A unique case presented with history of 8 miscarriages for genetic counseling.The last abortus material evaluation showed monosomy of chromosome X(Turner syndrome)in all the analyzed cells.There was a history of infertility and also repeated second trimester abortions on the paternal side.On the maternal side,there was a history of intellectual disability.Diagnose:History of repeated abnormal pregnancy outcomes.Wife’s karyotype is normal;however,husband shows translocation between chromosome 4 and 22.Intervention:Peripheral blood sample around 3 mL was collected for karyotype.Embryo biopsy was done and DNA was extracted and processed for whole exome sequencing.Outcomes:Wife’s karyotype is normal and husband has translocation between chromosome 4 and 22.Surprisingly,the entire pregnancy outcome including embryo screening has different,complete or partial aneuploidies of chromosomes other than chromosome 4 and 22.Main lesson:Though the translocation in one of the parent is balanced,we have to think beyond traditional ways for evaluating a couple with repeated pregnancy loss as we cannot predict the errors at cell division.Option of in vitro fertilization and preimplantation genetic diagnosis in couples having balanced translocations should be discussed so that early intervention can prevent the agony of pregnancy loss. 展开更多
关键词 In vitro fertilization KARYOTYPE Products of conception Preimplantation genetic testing PGT Recurrent pregnancy loss
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Increasing realism in modelling energy losses in railway vehicles and their impact to energy-efficient train control
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作者 Michael Nold Francesco Corman 《Railway Engineering Science》 EI 2024年第3期257-285,共29页
The reduction of energy consumption is an increasingly important topic of the railway system.Energy-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruisi... The reduction of energy consumption is an increasingly important topic of the railway system.Energy-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruising speed to hold,how long one should coast over a suitable space,and when to brake.Most approaches in literature and industry greatly simplify a lot of nonlinear effects,such that they ignore mostly the losses due to energy conversion in traction components and auxiliaries.To fill this research gap,a series of increasingly detailed nonlinear losses is described and modelled.We categorize an increasing detail in this representation as four levels.We study the impact of those levels of detail on the energy optimal speed trajectory.To do this,a standard approach based on dynamic programming is used,given constraints on total travel time.This evaluation of multiple test cases highlights the influence of the dynamic losses and the power consumption of auxiliary components on railway trajectories,also compared to multiple benchmarks.The results show how the losses can make up 50%of the total energy consumption for an exemplary trip.Ignoring them would though result in consistent but limited errors in the optimal trajectory.Overall,more complex trajectories can result in less energy consumption when including the complexity of nonlinear losses than when a simpler model is considered.Those effects are stronger when the trajectory includes many acceleration and braking phases. 展开更多
关键词 Train trajectory optimization Energy-efficient train control(EETC) Dynamic efficiency Power losses in railway vehicles
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Unraveling the efficiency losses and improving methods in quantum dot-based infrared up-conversion photodetectors
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作者 Jiao Jiao Liu Xinxin Yang +3 位作者 Qiulei Xu Ruiguang Chang Zhenghui Wu Huaibin Shen 《Opto-Electronic Science》 2024年第4期1-11,共11页
Quantum dot-based up-conversion photodetector,in which an infrared photodiode(PD)and a quantum dot light-emitting diode(QLED)are back-to-back connected,is a promising candidate for low-cost infrared imaging.However,th... Quantum dot-based up-conversion photodetector,in which an infrared photodiode(PD)and a quantum dot light-emitting diode(QLED)are back-to-back connected,is a promising candidate for low-cost infrared imaging.However,the huge efficiency losses caused by integrating the PD and QLED together hasn’t been studied sufficiently.This work revealed at least three origins for the efficiency losses.First,the PD unit and QLED unit usually didn’t work under optimal conditions at the same time.Second,the potential barriers and traps at the interconnection between PD and QLED units induced unfavorable carrier recombination.Third,much emitted visible light was lost due to the strong visible absorption in the PD unit.Based on the understandings on the loss mechanisms,the infrared up-conversion photodetectors were optimized and achieved a breakthrough photon-to-photon conversion efficiency of 6.9%.This study provided valuable guidance on how to optimize the way of integration for up-conversion photodetectors. 展开更多
关键词 infrared colloidal quantum dots up-conversion photodetector integration loss INTERCONNECTION voltage allocation
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Optimal Sizing and Power Losses Reduction of Photovoltaic Systems Using PVsyst Software
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作者 Andre Boussaibo Armel Duvalier Pene Kitmo   《Journal of Power and Energy Engineering》 2024年第7期23-38,共16页
This paper presents a method for optimizing a grid-connected photovoltaic system through an LCL filter. An algorithm based on particle swarm optimization (PSO) is used to determine the number of batteries, the number ... This paper presents a method for optimizing a grid-connected photovoltaic system through an LCL filter. An algorithm based on particle swarm optimization (PSO) is used to determine the number of batteries, the number of panels in series and in parallel, as well as to evaluate the joule losses due to cable heating and the switching losses of the multilevel inverters. This system is applied to a village named YAGOUA, located in the far north of Cameroon. The evaluation of the Joule effect and the switching losses as well as the regulation of the voltage level at the point of common coupling (PCC) are carried out in PVsyst and Matlab software, then at IEEE 33 bus. This algorithm reduced the Joule losses to 1.2% and the switching losses to 2.2%. A power of 210.4 MWh is produced, to be injected in the electrical network via an LCL filter. The THD calculation gave a rate of 3.015% in accordance with the 519 standards. Synchronization through the Phase Locked Loop (PLL) is performed. After the power was injected into the grid, the voltage and current remained in phase, showing the power factor correction and the efficiency of the filter. According to NASA meteorological data, the locality of YAGOUA gives the global solar irradiation forecast of 6.8 kW/m2. 展开更多
关键词 Five Level Inverter LCL Filter MPPT Power losses PVsyst
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Assessment of Intangible Losses in Earthquake Engineering
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作者 Jaime García-Pérez Orlando Díaz-López Eric García-López 《Open Journal of Civil Engineering》 2024年第3期469-485,共17页
In order to find optimum design parameters in earthquake engineering, an objective function is optimized. This function comprises the initial cost of a structure and the cost due to the damage of earthquakes. Intangib... In order to find optimum design parameters in earthquake engineering, an objective function is optimized. This function comprises the initial cost of a structure and the cost due to the damage of earthquakes. Intangible losses may be included in the latter, such as how much society is willing to invest to preserve a human life. In this paper, the expression of the objective function is developed in terms of the seismic design coefficient, and the aforementioned intangible loss is calculated from both the individual point of view and that of society. The calculation of the intangible is based on utility curves. Finally, optimum seismic design coefficients are calculated for a firm ground site. 展开更多
关键词 Seismic Risk Optimum Coefficients Structural Reliability Intangible losses UTILITY
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基于Focal Loss改进LightGBM的供水管网毛刺数据检测
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作者 薛浩 马静 郭小宇 《计算机与现代化》 2024年第9期74-81,90,共9页
针对数据不平衡导致的管网毛刺数据检测召回率偏低问题,提出一种Focal Loss改进LightGBM的管网毛刺数据检测方法。首先,结合管网毛刺数据的特点,针对性构造邻域相关特征。其次,将Focal Loss函数引入LightGBM,提高模型对难以检测的毛刺... 针对数据不平衡导致的管网毛刺数据检测召回率偏低问题,提出一种Focal Loss改进LightGBM的管网毛刺数据检测方法。首先,结合管网毛刺数据的特点,针对性构造邻域相关特征。其次,将Focal Loss函数引入LightGBM,提高模型对难以检测的毛刺样本的权重,并对Focal Loss不同的参数取值进行实验,以平衡精确率与召回率。最后,选择不同参数的Focal Loss进行模型融合,进一步提升模型对不平衡毛刺数据的检测性能。在某市供水管网的真实数据上进行实验,结果表明,对比基于交叉熵损失函数的单一模型,本文提出的Focal Loss改进后的融合模型在毛刺数据上召回率和F1值的提升幅度达33.3和18个百分点,但毛刺数据的精确率还有待进一步提升。本文所提方法从损失函数入手,动态调整难易样本的权重,有效地提升了不平衡数据下的毛刺数据的检测性能。 展开更多
关键词 异常检测 Focal loss LightGBM 不平衡数据 毛刺数据
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Drip fertigation and plant hedgerows significantly reduce nitrogen and phosphorus losses and maintain high fruit yields in intensive orchards 被引量:3
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作者 SONG Ke QIN Qin +5 位作者 YANG Ye-feng SUN Li-juan SUN Ya-fei ZHENG Xian-qing Lü Wei-guang XUE Yong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期598-610,共13页
A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake Basin.Nitrogen and phosp... A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake Basin.Nitrogen and phosphorus runoff over a whole year were measured by using successional runoff water collection devices.The four experimental treatments were conventional fertilization(CK),drip fertigation(DF),conventional fertilization combined with plant hedgerows(C+H),and drip fertigation combined with plant hedgerows(D+H).The results from one year of continuous monitoring showed a significant positive correlation between precipitation and surface runoff discharge.Surface runoff discharge under the treatments without plant hedgerows totaled 15.86%of precipitation,while surface runoff discharge under the treatments with plant hedgerows totaled 12.82%of precipitation.Plant hedgerows reduced the number of runoff events and the amount of surface runoff.Precipitation is the main driving force for the loss of nitrogen and phosphorus in surface runoff,and fertilization is an important factor affecting the losses of nitrogen and phosphorus.In CK,approximately 7.36%of nitrogen and 2.63%of phosphorus from fertilization entered the surface water through runoff.Drip fertigation reduced the accumulation of nitrogen and phosphorus in the surface soil and lowered the runoff loss concentrations of total nitrogen(TN)and total phosphorus(TP).Drip fertigation combined with plant hedgerows significantly reduced the overall TN and TP losses by 45.38 and 36.81%,respectively,in comparison to the CK totals.Drip fertigation increased the vertical migration depth of nitrogen and phosphorus nutrients and reduced the accumulation of nitrogen and phosphorus in the surface soil,which increased the pear yield.The promotion of drip fertigation combined with plant hedgerows will greatly reduce the losses of nitrogen and phosphorus to runoff and maintain the high fruit yields in the intensive orchards of the Tai Lake Basin. 展开更多
关键词 drip fertigation plant hedgerows surface runoff nitrogen and phosphorus losses fruit yields
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MPC-based Torque Distribution for Planar Motion of Four-wheel Independently Driven Electric Vehicles:Considering Motor Models and Iron Losses 被引量:3
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作者 Yiyan Su Deliang Liang Peng Kou 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第1期45-53,共9页
The most critical obstacle for four-wheel independently driven electric vehicles(4WID-EVs)is the driving range.Being the actuators of 4WID-EVs,motors account for its major power consumption.In this sense,by properly d... The most critical obstacle for four-wheel independently driven electric vehicles(4WID-EVs)is the driving range.Being the actuators of 4WID-EVs,motors account for its major power consumption.In this sense,by properly distributing torques to minimize the power consumption,the driving range of 4WID-EV can be effectively improved.This paper proposes a model predictive control(MPC)-based torque distribution scheme,which minimizes the power consumption of 4WID-EVs while guaranteeing its tracking performance of planar motions.By incorporating the motor model considering iron losses,the optimal torque distribution can be achieved without an additional torque controller.Also,for this reason,the proposed control scheme is computationally efficient,since the power consumption term to be optimized,which is expressed as the product of the motor voltages and currents,is much simpler than that derived from the efficiency map.With reasonable simplification and linearization,the MPC problem is converted to a quadratic programming problem,which can be solved efficiently.The simulation results in MATLAB and CarSim co-simulation environments demonstrate that the proposed scheme effectively reduces power consumption with guaranteed tracking performance. 展开更多
关键词 four-wheel independently driven electric vehicles Model predictive control Motor models Iron losses
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Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity Transmission Lines
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作者 Ounyesiga Living Stephen Ndubuisi Nnamchi +2 位作者 Kelechi John Ukagwu Abubakar Abdulkarim Zaid Oluwadurotimi Jagun 《Energy and Power Engineering》 CAS 2023年第2期127-150,共24页
The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques... The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages. 展开更多
关键词 MINIMIZATION Power losses Transmission Lines Corona and Ohms losses Transmission Model
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Financial Losses Associated with Bovine Brucellosis (Brucella abortus) in Carchi-Ecuador
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作者 Marcelo Ibarra Martin Campos +5 位作者 Christian Ibarra Urgilés Gladys Danny Huera Milena Gutiérrez Andrea Chamorro Luis Núñez 《Open Journal of Animal Sciences》 CAS 2023年第2期205-216,共12页
Brucellosis is an infectious disease of worldwide distribution, which has a great economic impact due to the productive and reproductive losses that it causes, in addition to the serious public health problem. The aim... Brucellosis is an infectious disease of worldwide distribution, which has a great economic impact due to the productive and reproductive losses that it causes, in addition to the serious public health problem. The aim of this study is to estimate the economic losses, through financial analysis, caused by bovine brucellosis in the province of Carchi, over a one-year period. A random sampling was used to determine the prevalence in the study area, where 2976 animals were considered, and the Rose Bengal (RB) test was used as a screening test and the Fluorescence Polarized Assay (FPA) as a confirmatory test, obtaining a prevalence of 8.2% (244/2976). In addition, parameters associated to the losses caused by brucellosis in cattle were determined by literature review. To estimate costs, field information was collected through a survey of a total of 100 randomly selected farmers. The loss estimated due to calves lost as a result of abortions and neonatal death was USD. 79170.00. The loss due to death of 4 cows as a result of metritis was estimated at USD. 5000.00. The cost of examination and treatment of aborted cows was USD. 20100.00. The losses due to reduction in milk production from aborted and non-aborted seropositive cows were estimated at USD. 158114.21. The financial losses due to brucellosis in province of Carchi were estimated at USD. 262384.21. 展开更多
关键词 Bovine Brucellosis Economic losses Carchi-Ecuador
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A crosstalk-free dual-mode sweat sensing system for naked-eye sweat loss quantification via changes in structural reflectance 被引量:1
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作者 Bowen Zhong Hao Xu +3 位作者 Xiaokun Qin Lingchen Liu Hailong Wang Lili Wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期428-438,共11页
Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal m... Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal method for the fabrication of colorimetric microfluidics designed for sweat loss monitoring remains challenging.In this study,we propose a novel laserengraved surface roughening strategy for various flexible substrates.This process permits the construction of microchannels that show distinct structural reflectance changes before and after sweat filling.By leveraging these unique optical properties,we have developed a fully laser-engraved microfluidic device for the quantification of naked-eye sweat loss.This sweat loss sensor is capable of a volume resolution of 0.5µL and a total volume capacity of 11µL,and can be customized to meet different performance requirements.Moreover,we report the development of a crosstalk-free dual-mode sweat microfluidic system that integrates an Ag/AgCl chloride sensor and a matching wireless measurement flexible printed circuit board.This integrated system enables the real-time monitoring of colorimetric sweat loss signals and potential ion concentration signals without crosstalk.Finally,we demonstrate the potential practical use of this microfluidic sweat loss sensor and its integrated system for sports medicine via on-body studies. 展开更多
关键词 Sweat loss sensor Microfluidic design Structural reflectance Dual-mode integration Crosstalk-free
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Post-Harvest Constraints: Fungi and Insects Responsible for Rice (Oryza spp) Losses during Storage in Cameroon
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作者 Delphine Mapiemfu-Lamare Erasmus Nchuaji Tang +4 位作者 Youmma Douksouna Ajebesone Francis Ngome Christopher Suh Blaise Nangsingnyuy Tatah Zachée Ambang 《Agricultural Sciences》 2023年第6期785-803,共19页
The magnitude of rice grain losses during storage is huge and warrants critical attention. We investigated the diversity of fungi and insect contamination related to losses of domestic and imported rice from local mil... The magnitude of rice grain losses during storage is huge and warrants critical attention. We investigated the diversity of fungi and insect contamination related to losses of domestic and imported rice from local mills and markets, stored under room conditions for 10 weeks in Cameroon. The highest percentage discolored grain was on imported milled white rice (3.5%), 10 weeks after storage. In general, imported rice samples contained the highest fungal load with a proportion of 65.90% compared to 34.3% for domestic samples. Weight loss due to insect damage was up to 19.9% in white milled domestic rice. Among the 67 isolated fungi strains, the genus Aspergillus had the highest prevalence (63.8%). From all the samples, 877 insects were collected with 719 (81.9%) of Sitophilus. It is urgent to develop sustainable and affordable storage methods to limit insect and fungi infestation on rice in Cameroon. 展开更多
关键词 loss Quantity Quality Safety Cameroon
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Genetically modified pigs:Emerging animal models for hereditary hearing loss 被引量:1
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作者 Xiao Wang Tian-Xia Liu +7 位作者 Ying Zhang Liang-Wei Xu Shuo-Long Yuan A-Long Cui Wei-Wei Guo Yan-Fang Wang Shi-Ming Yang Jian-Guo Zhao 《Zoological Research》 SCIE CSCD 2024年第2期284-291,共8页
Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and e... Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models. 展开更多
关键词 PIGS Animal models Hereditary hearing loss Genetic modification Inner ear
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Distributed dynamic event-based finite-time dissipative synchronization control for semi-Markov switched fuzzy cyber-physical systems against random packet losses
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作者 伍锡如 张煜翀 +1 位作者 张畑畑 张斌磊 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期328-342,共15页
This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzz... This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzzy model. To save the network communication burden, a distributed dynamic event-triggered mechanism is developed to restrain the information update. Besides, random packet dropouts following the Bernoulli distribution are assumed to occur in sensor to controller channels, where the triggered control input is analyzed via an equivalent method containing a new stochastic variable. By establishing the mode-dependent Lyapunov–Krasovskii functional with augmented terms, the finite-time boundness of the error system limited to strict dissipativity is studied. As a result of the help of an extended reciprocally convex matrix inequality technique, less conservative criteria in terms of linear matrix inequalities are deduced to calculate the desired control gains. Finally, two examples in regard to practical systems are provided to display the effectiveness of the proposed theory. 展开更多
关键词 cyber-physical systems finite-time synchronization distributed dynamic event-triggered mechanism random packet losses
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Relative Impacts of Sea Ice Loss and Atmospheric Internal Variability on the Winter Arctic to East Asian Surface Air Temperature Based on Large-Ensemble Simulations with NorESM2 被引量:1
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作者 Shengping HE Helge DRANGE +4 位作者 Tore FUREVIK Huijun WANG Ke FAN Lise Seland GRAFF Yvan J.ORSOLINI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1511-1526,共16页
To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simu... To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simulations carried out by the Norwegian Earth System Model with a coupled atmosphere–land surface model, forced by seasonal sea ice conditions from preindustrial, present-day, and future periods. Each ensemble member within the same set uses the same forcing but with small perturbations to the atmospheric initial state. Hence, the difference between the present-day(or future) ensemble mean and the preindustrial ensemble mean provides the ice-loss-induced response, while the difference of the individual members within the present-day(or future) set is the effect of atmospheric internal variability. Results indicate that both present-day and future sea ice loss can force a negative phase of the Arctic Oscillation with a WACE pattern in winter. The magnitude of ice-induced Arctic warming is over four(ten) times larger than the ice-induced East Asian cooling in the present-day(future) experiment;the latter having a magnitude that is about 30% of the observed cooling. Sea ice loss contributes about 60%(80%) to the Arctic winter warming in the present-day(future) experiment. Atmospheric internal variability can also induce a WACE pattern with comparable magnitudes between the Arctic and East Asia. Ice-lossinduced East Asian cooling can easily be masked by atmospheric internal variability effects because random atmospheric internal variability may induce a larger magnitude warming. The observed WACE pattern occurs as a result of both Arctic sea ice loss and atmospheric internal variability, with the former dominating Arctic warming and the latter dominating East Asian cooling. 展开更多
关键词 Arctic sea ice loss warm Arctic–cold East Asia atmospheric internal variability large-ensemble simulation NorESM2 PAMIP
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Robust fault detection for delta operator switched fuzzy systems with bilateral packet losses
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作者 FAN Yamin ZHANG Duanjin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期214-223,共10页
Considering packet losses, time-varying delay, and parameter uncertainty in the switched fuzzy system, this paper designs a robust fault detection filter at any switching rate and analyzes the H∞ performance of the s... Considering packet losses, time-varying delay, and parameter uncertainty in the switched fuzzy system, this paper designs a robust fault detection filter at any switching rate and analyzes the H∞ performance of the system. Firstly, the Takagi-Sugeno(T-S) fuzzy model is used to establish a global fuzzy model for the uncertain nonlinear time-delay switched system,and the packet loss process is modeled as a mathematical model satisfying Bernoulli distribution. Secondly, through the average dwell time method and multiple Lyapunov functions, the exponentially stable condition of the nonlinear network switched system is given. Finally, specific parameters of the robust fault detection filter can be obtained by solving linear matrix inequalities(LMIs). The effectiveness of the method is verified by simulation results. 展开更多
关键词 switched fuzzy system robust fault detection timevarying delay bilateral packet losses UNCERTAINTY average dwell time method
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Optimal Placement and Sizing of Distributed Generations for Power Losses Minimization Using PSO-Based Deep Learning Techniques
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作者 Bello-Pierre Ngoussandou Nicodem Nisso +1 位作者 Dieudonné Kaoga Kidmo   Kitmo 《Smart Grid and Renewable Energy》 2023年第9期169-181,共13页
The integration of distributed generations (DGs) into distribution systems (DSs) is increasingly becoming a solution for compensating for isolated local energy systems (ILESs). Additionally, distributed generations ar... The integration of distributed generations (DGs) into distribution systems (DSs) is increasingly becoming a solution for compensating for isolated local energy systems (ILESs). Additionally, distributed generations are used for self-consumption with excess energy injected into centralized grids (CGs). However, the improper sizing of renewable energy systems (RESs) exposes the entire system to power losses. This work presents an optimization of a system consisting of distributed generations. Firstly, PSO algorithms evaluate the size of the entire system on the IEEE bus 14 test standard. Secondly, the size of the system is allocated using improved Particles Swarm Optimization (IPSO). The convergence speed of the objective function enables a conjecture to be made about the robustness of the proposed system. The power and voltage profile on the IEEE 14-bus standard displays a decrease in power losses and an appropriate response to energy demands (EDs), validating the proposed method. 展开更多
关键词 Distributed Generations Deep Learning Techniques Improved Particle Swarm Optimization Power losses Power losses Minimization Optimal Placement
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Automated Actuarial Data Analytics-Based Inflation Adjusted Frequency Severity Loss Reserving Model
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作者 Brighton Mahohoho 《Open Journal of Statistics》 2024年第3期341-393,共53页
In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological ... In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological advancement currently at hand. As a result, the development of the alternative Artificial Intelligence Based Automated Actuarial Loss Reserving Methodology which captures diverse risk profiles for various policyholders through augmenting the Micro Finance services, Auto Insurance Services and Both Services lines of business on the same platform through the computation of the Comprehensive Automated Actuarial Loss Reserves (CAALR) has been implemented in this paper. The introduction of the four further types of actuarial loss reserves to those existing in the actuarial literature seems to significantly reduce lapse rates, reduce the reinsurance costs as well as expenses and outgo. As a matter of consequence, this helps to bring together a combination of new and existing policyholders in the insurance company. The frequency severity models have been extended in this paper using ten machine learning algorithms which ultimately leads to the derivation of the proposed machine learning-based actuarial loss reserving model which remarkably performed well when compared to the traditional chain ladder actuarial reserving method using simulated data. 展开更多
关键词 Automated Actuarial loss Reserves Artificial Intelligence Micro Finance loss Reserving Auto Insurance loss Reserving Both Services loss Reserving
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Hemoglobin loss method calculates blood loss during pancreaticoduodenectomy and predicts bleeding-related risk factors
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作者 Chao Yu Yi-Min Lin Guo-Zhe Xian 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期419-428,共10页
BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is... BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is no accurate,objective me-thod to evaluate the amount of blood loss in PD patients.We retrospectively analyzed the clinical data of 341 patients who underwent PD in Shandong Provincial Hospital from March 2017 to February 2019.According to different surgical methods,they were divided into an open PD(OPD)group and a laparoscopic PD(LPD)group.The differences and correlations between the in-traoperative estimation of blood loss(IEBL)obtained by visual inspection and the intraoperative calculation of blood loss(ICBL)obtained using the Hb loss method were analyzed.ICBL,IEBL and perioperative calculation of blood loss(PCBL)were compared between the two groups,and single-factor regression analysis was performed.RESULTS There was no statistically significant difference in the preoperative general patient information between the two groups(P>0.05).PD had an ICBL of 743.2(393.0,1173.1)mL and an IEBL of 100.0(50.0,300.0)mL(P<0.001).There was also a certain correlation between the two(r=0.312,P<0.001).Single-factor analysis of ICBL showed that a history of diabetes[95%confidence interval(CI):53.82-549.62;P=0.017]was an independent risk factor for ICBL.In addition,the single-factor analysis of PCBL showed that body mass index(BMI)(95%CI:0.62-76.75;P=0.046)and preoperative total bilirubin>200μmol/L(95%CI:7.09-644.26;P=0.045)were independent risk factors for PCBL.The ICBLs of the LPD group and OPD group were 767.7(435.4,1249.0)mL and 663.8(347.7,1138.2)mL,respectively(P>0.05).The IEBL of the LPD group 200.0(50.0,200.0)mL was slightly greater than that of the OPD group 100.0(50.0,300.0)mL(P>0.05).PCBL was greater in the LPD group than the OPD group[1061.6(612.3,1632.3)mL vs 806.1(375.9,1347.6)mL](P<0.05).CONCLUSION The ICBL in patients who underwent PD was greater than the IEBL,but there is a certain correlation between the two.The Hb loss method can be used to evaluate intraoperative blood loss.A history of diabetes,preoperative bilirubin>200μmol/L and high BMI increase the patient's risk of bleeding. 展开更多
关键词 PANCREATICODUODENECTOMY Hemoglobin loss Calculated blood loss Estimated blood loss
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