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Multi-Model Approach for Assessing the Influence of Calibration Criteria on the Water Balance in Ouémé Basin
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作者 Aymar Yaovi Bossa Mahutin Aristide Oluwatobi Kpossou +1 位作者 Jean Hounkpè Félicien Djigbo Badou 《Journal of Water Resource and Protection》 CAS 2024年第3期207-218,共12页
Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteri... Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling. 展开更多
关键词 Hydrological Modelling Performance Criteria Water balance Ouémé Basin
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Harmonic balance simulation of the influence of component uniformity and reliability on the performance of a Josephson traveling wave parametric amplifier
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作者 郑煜臻 熊康林 +1 位作者 冯加贵 杨辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期339-343,共5页
A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A ... A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes. 展开更多
关键词 Josephson traveling wave parametric amplifier(JTWPA) harmonic balance method YIELDS UNIFORMITY
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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYSTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network
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作者 Xin Shao Qing Liu +3 位作者 Zicheng Xin Jiangshan Zhang Tao Zhou Shaoshuai Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期106-117,共12页
The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ... The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter. 展开更多
关键词 basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model
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Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk
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作者 Dong Pan Xu Gui +3 位作者 Jiayin Xu Yuming Shen Haoran Xu Yinghao Ma 《Energy Engineering》 EI 2024年第5期1309-1328,共20页
With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,... With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit. 展开更多
关键词 Carbon emission risk power balance risk thermal power retrofit generation expansion planning
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging balance encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography SOMATOSENSORY VESTIBULAR visual
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Research on Work-Life Balance of Female Employees
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作者 Ming Chen 《Proceedings of Business and Economic Studies》 2024年第1期145-149,共5页
Nowadays,the pace of work and life is accelerating rapidly,accompanied by significant changes in work content and family structure.Enterprises and employees are encountering various pressures and conflicts.Female empl... Nowadays,the pace of work and life is accelerating rapidly,accompanied by significant changes in work content and family structure.Enterprises and employees are encountering various pressures and conflicts.Female employees,in particular,are experiencing increasing pressure in both social labor and family affairs,resulting in ongoing conflicts between work and life.Achieving a balance between these two domains is crucial for female employees.This article aims to analyze the influencing factors of work-life balance for female employees and to propose useful strategies to help them improve it. 展开更多
关键词 Work-life balance Work-life conflict Female employees
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Analyzing the Combination Effects of Repetitive Transcranial Magnetic Stimulation and Motor Control Training on Balance Function and Gait in Patients with Stroke-Induced Hemiplegia
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作者 Xiaoqing Ma Zhen Ma +2 位作者 Ye Xu Meng Han Hui Yan 《Proceedings of Anticancer Research》 2024年第1期54-60,共7页
Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’bala... Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’balance function and gait.Methods:Fifty-two cases of hemiplegic stroke patients were randomly divided into two groups,26 in the control group and 26 in the observation group,using computer-generated random grouping.All participants underwent conventional treatment and rehabilitation training.In addition to these,the control group received repetitive transcranial magnetic pseudo-stimulation therapy+motor control training,while the observation group received repetitive transcranial magnetic stimulation therapy+motor control training.The balance function and gait parameters of both groups were compared before and after the interventions and assessed the satisfaction of the interventions in both groups.Results:Before the invention,there were no significant differences in balance function scores and each gait parameter between the two groups(P>0.05).However,after the intervention,the observation group showed higher balance function scores compared to the control group(P<0.05).The observation group also exhibited higher step speed and step frequency,longer step length,and a higher overall satisfaction level with the intervention compared to the control group(P<0.05).Conclusion:The combination of repetitive transcranial magnetic stimulation and motor control training in the treatment of stroke-induced hemiplegia has demonstrated positive effects.It not only improves the patient’s balance function and gait but also contributes to overall physical rehabilitation. 展开更多
关键词 Stroke-induced hemiplegia Repetitive transcranial magnetic stimulation Motor control training balance function GAIT
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Model Predictive Control for Cascaded H-Bridge PV Inverter with Capacitor Voltage Balance
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作者 Xinwei Wei Wanyu Tao +4 位作者 Xunbo Fu Xiufeng Hua Zhi Zhang Xiaodan Zhao Chen Qin 《Journal of Electronic Research and Application》 2024年第2期79-85,共7页
We designed an improved direct-current capacitor voltage balancing control model predictive control(MPC)for single-phase cascaded H-bridge multilevel photovoltaic(PV)inverters.Compared with conventional voltage balanc... We designed an improved direct-current capacitor voltage balancing control model predictive control(MPC)for single-phase cascaded H-bridge multilevel photovoltaic(PV)inverters.Compared with conventional voltage balanc-ing control methods,the method proposed could make the PV strings of each submodule operate at their maximum power point by independent capacitor voltage control.Besides,the predicted and reference value of the grid-connected current was obtained according to the maximum power output of the maximum power point tracking.A cost function was con-structed to achieve the high-precision grid-connected control of the CHB inverter.Finally,the effectiveness of the proposed control method was verified through a semi-physical simulation platform with three submodules. 展开更多
关键词 Model predictive control(MPC) Photovoltaic system Cascaded H-bridge(CHB)inverter Capacitor voltage balance
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YOLOv4-Balance:样本均衡的目标检测网络
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作者 周泽清 於跃成 顾宙瑜 《软件导刊》 2024年第2期1-8,共8页
针对因数据集中小目标样本数量不足且分布不均衡,导致算法对小目标检测精度低的问题,在多尺度目标检测模型YOLOv4的基础上,提出一种融合动态损失反馈与数据增强的多尺度目标检测算法YOLOv4-Balance。首先,提出一种基于图像组合拼接的数... 针对因数据集中小目标样本数量不足且分布不均衡,导致算法对小目标检测精度低的问题,在多尺度目标检测模型YOLOv4的基础上,提出一种融合动态损失反馈与数据增强的多尺度目标检测算法YOLOv4-Balance。首先,提出一种基于图像组合拼接的数据增强算法U-Mix,均衡小目标样本的分布,提高数据集中的小目标学习样本质量。其次,基于模型训练迭代时的Loss反馈,提出一种利用动态损失反馈的多尺度模型训练算法DLF,以提高训练过程中小目标样本损失对模型学习的贡献度。实验结果表明,该算法在MSCOCO数据集上的平均精度较基线模型YO⁃LOv4提升了约2.1%,对小目标样本的检测精度提升了约2.8%。该算法不会引入额外的计算开销,且模型收敛快速,有助于高效进行训练。 展开更多
关键词 目标检测 样本均衡 数据增强 反馈驱动 多尺度
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Incentive-compatible and budget balanced AGV mechanism for peer-to-peer energy trading in smart grids 被引量:1
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作者 Yujia Chen Wei Pei +1 位作者 Hao Xiao Tengfei Ma 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期26-35,共10页
Peer-to-peer(P2P)energy trading refers to a type of decentralized transaction,where the energy from distributed energy resources is directly traded between peers.A key challenge in peer-to-peer energy trading is desig... Peer-to-peer(P2P)energy trading refers to a type of decentralized transaction,where the energy from distributed energy resources is directly traded between peers.A key challenge in peer-to-peer energy trading is designing a safe,efficient,and transparent trading model and operating mechanism.In this study,we consider a P2P trading environment based on blockchain technology,where prosumers can submit bids or offers without knowing the reports of others.We propose an Arrow-d’Aspremont-Gerard-Varet(AGV)-based mechanism to encourage prosumers to submit their real reserve price and determine the P2P transaction price.We demonstrate that the AGV mechanism can achieve Bayesian incentive compatibility and budget balance.Kernel density estimation(KDE)is used to derive the prior distribution from the historical bid/offer information of the agents.Case studies are carried out to analyze and evaluate the proposed mechanism.Simulation results verify the effectiveness of the proposed mechanism in guiding agents to report the true reserve price while maximizing social welfare.Moreover,we discuss the advantages of budget balance for decentralized trading by comparing the Vickrey-Clarke-Groves(VCG)and AGV mechanisms. 展开更多
关键词 P2P energy trading AGV mechanism Budget balance Incentive compatibility
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Myricetin alleviates ovalbumin-induced allergic rhinitis in mice by regulating Th1/Th2 balance 被引量:1
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作者 Ya-Nan Shi Jin-Zhu Su +1 位作者 Juan Wang Jiang-Qiao Geng 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第7期306-314,共9页
Objective:To evaluate the effect of myricetin on ovalbumin(OVA)-induced allergic rhinitis in mice.Methods:Mice were sensitized and challenged using OVA(5%,500 mL)intraperitoneally and intranasally,respectively,on an a... Objective:To evaluate the effect of myricetin on ovalbumin(OVA)-induced allergic rhinitis in mice.Methods:Mice were sensitized and challenged using OVA(5%,500 mL)intraperitoneally and intranasally,respectively,on an alternative day for 14 days,followed by administration of myricetin(50,100,and 200 mg/kg)till day 21.Nasal symptoms,biochemical parameters,protein expressions,and histopathology were observed.Results:OVA-induced increased nasal symptoms including rubbing,sneezing,and discharge were significantly reduced by myricetin(100and 200 mg/kg)(P<0.05).Myricetin also protected against histamine challenge and attenuated elevated serum immunoglobulin E(IgE;total and OVA-specific),total IgG1,andβ-hexosaminidase levels,as well as leukotriene C4 and interleukins levels in nasal lavage fluid(P<0.05).Western blot analysis showed that myricetin significantly upregulated the protein expression of T-box expressed in T cells,while downregulating the protein expression of GATA binding protein 3,NF-κB,and IκB-α(P<0.05).Additionally,OVA-induced histopathological abberations in the nasal mucosa was markedly ameliorated by myricetin treatment(P<0.05).Conclusions:Myricetin exerts anti-allergic effects against OVAinduced allergic rhinitis via regulating Th1/Th2 balance. 展开更多
关键词 Allergic rhinitis GATA3 INTERLEUKINS MYRICETIN MONTELUKAST Ovalbumin Th1/Th2 balance
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Evaluation and prediction of earth pressure balance shield performance in complex rock strata:A case study in Dalian,China 被引量:1
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作者 Xiang Shen Dajun Yuan +2 位作者 Xing-Tao Lin Xiangsheng Chen Yuansheng Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1491-1505,共15页
This research explores the potential for the evaluation and prediction of earth pressure balance shield performance based on a gray system model.The research focuses on a shield tunnel excavated for Metro Line 2 in Da... This research explores the potential for the evaluation and prediction of earth pressure balance shield performance based on a gray system model.The research focuses on a shield tunnel excavated for Metro Line 2 in Dalian,China.Due to the large error between the initial geological exploration data and real strata,the project construction is extremely difficult.In view of the current situation regarding the project,a quantitative method for evaluating the tunneling efficiency was proposed using cutterhead rotation(R),advance speed(S),total thrust(F)and torque(T).A total of 80 datasets with three input parameters and one output variable(F or T)were collected from this project,and a prediction framework based gray system model was established.Based on the prediction model,five prediction schemes were set up.Through error analysis,the optimal prediction scheme was obtained from the five schemes.The parametric investigation performed indicates that the relationships between F and the three input variables in the gray system model harmonize with the theoretical explanation.The case shows that the shield tunneling performance and efficiency are improved by the tunneling parameter prediction model based on the gray system model. 展开更多
关键词 Evaluation of earth pressure balance shield PERFORMANCE Gray system model Metro construction Rock strata Field data prediction
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Challenges in Work-Family Balance and Support Needs of Japanese Parents with Nursery School-Aged Children
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作者 Yuko Shimoda Miyuki Ishii Yuichi Hori 《Health》 2023年第6期622-639,共18页
We aimed to identify the challenges parents face raising preschool-aged children when trying to maintain a good work-family balance. We also highlight how public health nurses can support the community in this regard.... We aimed to identify the challenges parents face raising preschool-aged children when trying to maintain a good work-family balance. We also highlight how public health nurses can support the community in this regard. Seven Japanese parents volunteered to participate, and individual in-depth interviews were conducted from May to October 2021. We analyzed the recorded interview data using qualitative descriptive methods. Three main themes concerning work-family balance challenges were extracted: 1) conflicts between parents’ childcare and work roles, 2) issues related to institutions and social systems, and 3) a lack of informal support. Factors contributing to the difficulties were a lack of time to spend with their children;an imbalance in the division of housework and childcare roles between married couples;the employment environment in Japan that makes it difficult to pursue a career while raising children;a lack of childcare services, including childcare for sick children;inadequate consultation systems;and an aging grandparents’ generation owing to late marriages. To solve this problem, we suggest that in addition to establishing a reliable system for providing childcare, local public health nurses should work with childcare workers to create an environment in which parents feel comfortable discussing work-family balance, considering the time constraints of parents during the childrearing period, and use nursery schools as a place for parent-child support. 展开更多
关键词 Childrearing PARENT Public Health Nurse Work-Family balance
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Estimating Evapotranspiration Using Chloride Mass Balance in a New Mexico Paired Basin Study 2009-2019
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作者 Amy C. Lewis Daniel Cadol 《Journal of Water Resource and Protection》 CAS 2023年第4期115-129,共15页
A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin s... A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin study was established to investigate questions that have arisen regarding changes in water yield from forest treatments. Precipitation, stream flow, soil moisture, and chloride concentrations in precipitation and stream flow were measured to quantify the water budget components. The results from eleven years of data collection and analysis have a high degree of confidence with respect to measuring the water budget components based on the mass balance of water and chloride. The differences in the geologic structure and topography between the two paired basins appeared to impact the water budgets more than the forest treatments, except during periods when winter precipitation and snowmelt represented a significant component of inflow. Although this paired basin study was not able to portray a simple relationship between forest thinning and water yield, the chloride concentration methodology used to estimate evapotranspiration (ET) was successful. These detailed observations of chloride deposition and transport characteristics may be relevant for other researchers working in forested basins with substantial ET. ET rates were estimated by examining the cycle of chloride entering and exiting each basin over six integration periods. ET was estimated to be about 90% to 94% of precipitation in the treated basin and 77% to 86% in the control basin. The higher ET in the treated basin both before and after forest treatments may be due to the much greater area of west-facing hillslopes in the treated basin, which receive warm afternoon sun, and the greater area of rock cover in the control basin. Variation in the chloride concentration of collected precipitation samples from different sites indicates that horizontal precipitation of chloride in the tree canopy is an important consideration when using the chloride mass balance approach to calculate water budget components. 展开更多
关键词 EVAPOTRANSPIRATION Chloride Mass balance Paired Basins Water Budgets Horizontal Precipitation
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低频重复经颅磁刺激联合Balance-Trainer训练对脑卒中后平衡功能及下肢运动功能的影响 被引量:1
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作者 翟佳佳 施维 +4 位作者 朱冬燕 周三连 梁丽 曹慧 卢红建 《中国医药导报》 CAS 2023年第23期103-106,共4页
目的探究低频重复经颅磁刺激(rTMS)联合Balance-Trainer训练对脑卒中患者平衡功能及下肢运动功能的影响。方法选择2021年1月至2022年1月在南通大学第二附属医院康复医学科住院的70例脑卒中患者,采用随机数字表法分为BT组(23例)、rTMS组... 目的探究低频重复经颅磁刺激(rTMS)联合Balance-Trainer训练对脑卒中患者平衡功能及下肢运动功能的影响。方法选择2021年1月至2022年1月在南通大学第二附属医院康复医学科住院的70例脑卒中患者,采用随机数字表法分为BT组(23例)、rTMS组(24例)和联合组(23例)。三组均接受常规的康复治疗,BT组增加Balance-Trainer训练,rTMS组增加rTMS治疗,联合组给予rTMS治疗和Balance-Trainer训练,治疗8周。比较三组治疗前后Berg平衡量表(BBS)、Fugl-Meyer下肢运动功能量表(FMA-LE)、改良Barthel指数量表(MBI)评分及稳定性指数(SI)得分;观察三组不良反应发生情况。结果治疗后,三组BBS、FMA-LE、MBI评分较治疗前升高,SI得分较治疗前降低;且联合组BBS、FMA-LE、MBI评分高于BT组及rTMS组,SI得分低于BT组及rTMS组(P<0.05)。所有患者在治疗过程中均未出现癫痫等不良反应。结论低频rTMS联合Balance-Trainer训练能有效改善脑卒中患者平衡功能和下肢运动功能,提高患者的日常生活能力。 展开更多
关键词 重复经颅磁刺激 脑卒中 平衡功能 下肢运动功能
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A novel adaptive harmonic balance method with an asymptotic harmonic selection
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作者 Rongzhou LIN Lei HOU +3 位作者 Yi CHEN Yuhong JIN N.A.SAEED Yushu CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第11期1887-1910,共24页
The harmonic balance method(HBM)is one of the most widely used methods in solving nonlinear vibration problems,and its accuracy and computational efficiency largely depend on the number of the harmonics selected.The a... The harmonic balance method(HBM)is one of the most widely used methods in solving nonlinear vibration problems,and its accuracy and computational efficiency largely depend on the number of the harmonics selected.The adaptive harmonic balance(AHB)method is an improved HBM method.This paper presents a modified AHB method with the asymptotic harmonic selection(AHS)procedure.This new harmonic selection procedure selects harmonics from the frequency spectra of nonlinear terms instead of estimating the contribution of each harmonic to the whole nonlinear response,by which the additional calculation is avoided.A modified continuation method is proposed to deal with the variable size of nonlinear algebraic equations at different values of path parameters,and then all solution branches of the amplitude-frequency response are obtained.Numerical experiments are carried out to verify the performance of the AHB-AHS method.Five typical nonlinear dynamic equations with different types of nonlinearities and excitations are chosen as the illustrative examples.Compared with the classical HBM and Runge-Kutta methods,the proposed AHB-AHS method is of higher accuracy and better convergence.The AHB-AHS method proposed in this paper has the potential to investigate the nonlinear vibrations of complex high-dimensional nonlinear systems. 展开更多
关键词 harmonic balance method(HBM) adaptive harmonic balance(AHB)method harmonic selection nonlinear vibration multi-frequency excitation
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Active-passive radial-additive friction stir repairing of mechanical hole out of dimension tolerance of AZ31 magnesium alloy
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作者 Hua Liu Zhenlei Liu +3 位作者 Shude Ji Yumei Yue Zhibo Dong Changlong Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第9期3186-3199,共14页
In order to avoid the depth increasing of repaired hole and eliminate the super-fine grain band in stir zone by radial-additive friction stir repairing(R-AFSR), a solid-state repairing technique of active-passive radi... In order to avoid the depth increasing of repaired hole and eliminate the super-fine grain band in stir zone by radial-additive friction stir repairing(R-AFSR), a solid-state repairing technique of active-passive radial-additive friction stir repairing(AP-RAFSR) assisted by the truncated cone-shaped filling material was proposed in this study. The mechanical hole out of dimension tolerance of AZ31 magnesium alloy was chosen as the repaired object. The results indicated that the AP-RAFSR process rather than the R-AFSR process avoided the kissing bond in the bottom of the repairing interface under the condition of the tool pin length equal to the height of the standard mechanical hole.The continuously-distributed and large-length super-fine grain bands were eliminated in the stir zone by AP-RAFSR. The maximum tensile and compressive-shear strengths of repaired hole by AP-RAFSR reached 190.6 MPa and 138.9 MPa at 1200 rpm respectively, which were equivalent to 97.7% and 89.6% of those of the standard mechanical hole. This AP-RAFSR process assisted by the truncated cone-shaped filling material provides a new technique to obtain a no-depth-increasing, defect-free and high-strength repaired mechanical hole. 展开更多
关键词 active-passive radial-additive friction stir repairing Mechanical hole out of dimension tolerance Numerical simulation Microstructure Mechanical properties
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SimET: An open-source tool for estimating crop evapotranspiration and soil water balance for plants with multiple growth cycles
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作者 Minguo Liu Mei Yang Huimin Yang 《The Crop Journal》 SCIE CSCD 2023年第5期1579-1585,共7页
Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many de... Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many deficiencies, including complex operation, limited scalability, lack of batch processing, and a single ETc model. Here we present simET, an open-source software package written in the R programming language. Many concepts involved in crop ETc simulation are condensed into functions in the package. It includes three widely used crop ETc models built on these functions: the single-crop coefficient,double-crop coefficient, and Shuttleworth–Wallace models, along with tools for preparing model data and comparing estimates. SimET supports ETc simulation in crops with repeated growth cycles such as alfalfa, a perennial forage crop that is cut multiple times annually. 展开更多
关键词 Crop evapotranspiration Soil water balance Evapotranspiration model R package
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A novel energetic framework with the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole for energy-stability balanced explosive
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作者 Cheng-chuang Li Hao Gu +3 位作者 Jie Tang Guo-jie Zhang Guang-bin Cheng Hong-wei Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期184-192,共9页
In recent years,the introduction of fused rings own high density and low sensitivity has promoted the development of energetic materials.However,the development of energetic compounds containing fused and bridged ring... In recent years,the introduction of fused rings own high density and low sensitivity has promoted the development of energetic materials.However,the development of energetic compounds containing fused and bridged rings by introducing multiple nitrogen heterocycles at different sites of fused rings is still difficult to progress,which seriously limits the emergence of advanced energetic compounds.In this study,a series of energetic materials choosing different nitrogen rich heterocycles at the vacancies of the fused ring,i.e.,neutral compound 5,6 and their ionic derivatives(compounds 7-12)were designed and synthesized.Compounds 5 and 6 were further confirmed by single crystal X-ray diffraction,while the crystal analysis and theoretical calculations were carried out to explore the relationship between crystal structure and physicochemical properties.All of the newly synthesized compounds(5-12)are insensitive to mechanical stimulation(IS>40 J;FS≥342 N)and they own the high detonation velocity(D:8322-9075 m/s).Notably,hydrazine salt 11 own the higher detonation velocity(9075 m/s)and powder density(1.83 g/cm^(3)),but exhibits lower sensitivity(IS>40 J)than the classical energetic compound RDX(8795 m/s,1.80 g/cm^(3),7.5 J).It is obvious that the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole may be a new energetic skeleton for synthesising the heterocyclic compounds with balanced energy-stability. 展开更多
关键词 Fused and bridged rings Energetic skeleton balanced energy-stability Energetic materials
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