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Fossil architecture of meta-ophiolitic units in the Western Alps:new lithostratigraphic insights on blueschist units from the Ligurian-Piedmont Zone(upper Susa and Chisone valleys,Italy)
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作者 Alberto Corno 《Episodes》 2025年第4期433-450,共18页
The challenge of this work is to provide new data on the lithostratigraphy and tectono-stratigraphic evolution of two units belonging to the ophiolitic Ligurian-Piedmont zone of the Western Alps,i.e.the Albergian unit... The challenge of this work is to provide new data on the lithostratigraphy and tectono-stratigraphic evolution of two units belonging to the ophiolitic Ligurian-Piedmont zone of the Western Alps,i.e.the Albergian unit and the Lago Nero unit,exposed in the upper Susa and Chisone valleys(Northwestern Italy). 展开更多
关键词 lithostratigraphy fossil architecture lago nero tectono stratigraphic evolution Ligurian Piedmont zone Lago Nero unit albergian unit meta ophiolitic units
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Mixed-anion square-pyramid[SbS_(3)I_(2)]units causing strong second-harmonic generation intensity and large birefringence
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作者 Yu Zhou Lin-Tao Jiang +2 位作者 Xiao-Ming Jiang Bin-Wen Liu Guo-Cong Guo 《Chinese Chemical Letters》 2025年第4期507-510,共4页
Enhancement of the nonlinear optical(NLO)output power of lasers requires urgent development of an NLO crystal with a significant second-harmonic generation(SHG)response and sufficient birefringence for phase-matching ... Enhancement of the nonlinear optical(NLO)output power of lasers requires urgent development of an NLO crystal with a significant second-harmonic generation(SHG)response and sufficient birefringence for phase-matching capability;however,simultaneously optimizing these two key parameters remains a great challenge.In contrast to traditional single-anion units,the stereochemically-active lone pair Sb^(3+)ion is coordinated by S^(2-)and I^(-) ions to yield the mixed-anionic Sb SI chalcohalide that can enhance hyperpolarizability and anisotropic polarizability concurrently.As anticipated,Sb SI exhibited the largest SHG response(5.7×Ag Ga S_(2)@1.91μm)among phase-matching Sb-based sulfides,the favorable laser-induced damage threshold(LIDT,2.3×Ag Ga S_(2)@2.09μm),and the giant calculated birefringence(0.62@1.91μm).Structural analysis and computational simulations indicate that the highly polarizable mixed anion determine the enormous SHG response and birefringence. 展开更多
关键词 Chalcohalide Mixed-anionic units Nonlinear optical BIREFRINGENCE Structure-property relationship
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Diagnostic Method for Load Deviation in Ultra-Supercritical Units Based on MLNaNBDOS
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作者 Mingzhu Tang YujieHuang +1 位作者 Dongxu Ji Hao Yu 《Frontiers in Heat and Mass Transfer》 2025年第1期95-129,共35页
Load deviations between the output of ultra-supercritical(USC)coal-fired power units and automatic generation control(AGC)commands can adversely affect the safe and stable operation of these units and grid load dispat... Load deviations between the output of ultra-supercritical(USC)coal-fired power units and automatic generation control(AGC)commands can adversely affect the safe and stable operation of these units and grid load dispatching.Data-driven diagnostic methods often fail to account for the imbalanced distribution of data samples,leading to reduced classification performance in diagnosing load deviations in USC units.To address the class imbalance issue in USC load deviation datasets,this study proposes a diagnostic method based on the multi-label natural neighbor boundary oversampling technique(MLNaNBDOS).The method is articulated in three phases.Initially,the traditional binary oversampling strategy is improved by constructing a binary multi-label relationship for the load deviations in coal-fired units.Subsequently,an adaptive adjustment of the oversampling factor is implemented to determine the oversampling weight for each sample class.Finally,the generation of new instances is refined by dynamically evaluating the similarity between new cases and natural neighbors through a random factor,ensuring precise control over the instance generation process.In comparisons with nine benchmark methods across three imbalanced USC load deviation datasets,the proposed method demonstrates superior performance on several key evaluation metrics,including Micro-F1,Micro-G-mean,and Hamming Loss,with average values of 0.8497,0.9150,and 0.1503,respectively.These results substantiate the effectiveness of the proposed method in accurately diagnosing the sources of load deviations in USC units. 展开更多
关键词 Ultra-supercritical units load deviation multi-label learning class imbalance data oversampling
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Variable Integral Parameter Control Strategy for Secondary Frequency Regulation with Multiple Energy Storage Units
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作者 Jinyu Guo Xingxu Zhu +1 位作者 Zezhong Liu Cuiping Li 《Energy Engineering》 2025年第10期3961-3983,共23页
In high-renewable-energy power systems,the demand for fast-responding capabilities is growing.To address the limitations of conventional closed-loop frequency control,where the integral coefficient cannot dynamically ... In high-renewable-energy power systems,the demand for fast-responding capabilities is growing.To address the limitations of conventional closed-loop frequency control,where the integral coefficient cannot dynamically adjust the frequency regulation command based on the state of charge(SoC)of energy storage units,this paper proposes a secondary frequency regulation control strategy based on variable integral coefficients for multiple energy storage units.First,a power-uniform controller is designed to ensure that thermal power units gradually take on more regulation power during the frequency regulation process.Next,a control framework based on variable integral coefficients is proposed within the secondary frequency regulation model,along with an objective function that simultaneously considers both Automatic Generation Control(AGC)command tracking performance and SoC recovery requirements of energy storage units.Finally,a gradient descent optimization method is used to dynamically adjust the gain of the energy storage integral controller,allowingmultiple energy storage units to respond in real-time to AGC instructions and SoC variations.Simulation results confirmthe effectiveness of the proposedmethod.Compared to traditional strategies,the proposed approach takes into account the SoCdiscrepancies amongmultiple energy storage units and the duration of system net power imbalances.It successfully implements secondary frequency regulation while achieving dynamic power allocation among the units. 展开更多
关键词 Energy storage units secondary frequency regulation gradient descent optimization automatic generation control AGC signal distribution operation optimization
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Doubly-Fed Pumped Storage Units Participation in Frequency Regulation Control Strategy for New Energy Power Systems Based on Model Predictive Control 被引量:1
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作者 Yuanxiang Luo Linshu Cai Nan Zhang 《Energy Engineering》 2025年第2期765-783,共19页
Large-scale new energy grid connection leads to the weakening of the system frequency regulation capability,and the system frequency stability is facing unprecedented challenges.In order to solve rapid frequency fluct... Large-scale new energy grid connection leads to the weakening of the system frequency regulation capability,and the system frequency stability is facing unprecedented challenges.In order to solve rapid frequency fluctuation caused by new energy units,this paper proposes a new energy power system frequency regulation strategy with multiple units including the doubly-fed pumped storage unit(DFPSU).Firstly,based on the model predictive control(MPC)theory,the state space equations are established by considering the operating characteristics of the units and the dynamic behavior of the system;secondly,the proportional-differential control link is introduced to minimize the frequency deviation to further optimize the frequency modulation(FM)output of the DFPSU and inhibit the rapid fluctuation of the frequency;lastly,it is verified on theMatlab/Simulink simulation platform,and the results show that the model predictive control with proportional-differential control link can further release the FM potential of the DFPSU,increase the depth of its FM,effectively reduce the frequency deviation of the system and its rate of change,realize the optimization of the active output of the DFPSU and that of other units,and improve the frequency response capability of the system. 展开更多
关键词 Doubly-fed pumped storage unit model predictive control proportional-differential control link frequency regulation
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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Regulating the coplanarity of π-conjugated units through hydrogen bonding in FAHC_(2)O_(4) and FAH_(2)C_(3)N_(3)S_(3) crystals
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作者 Yi-Chang Yang Rui-Xi Wang +1 位作者 Li-Ming Wu Ling Chen 《Chinese Journal of Structural Chemistry》 2025年第10期62-67,共6页
The donor-acceptor hydrogen bonding strategy has been proposed to enforce coplanar packing of anisotropic π-conjugated units, thereby maximizing the material's achievable birefringence. Herein, employing this str... The donor-acceptor hydrogen bonding strategy has been proposed to enforce coplanar packing of anisotropic π-conjugated units, thereby maximizing the material's achievable birefringence. Herein, employing this strategy, we successfully obtain two highly coplanar birefringent crystals, FAHC_(2)O_(4) and FAH_(2)C_(3)N_(3)S_(3) (FA+: CH5N2, for-mamidinium). FAHC_(2)O_(4) shows a wide bandgap (4.20 eV), while FAH_(2)C_(3)N_(3)S_(3) exhibits a narrower bandgap (2.96 eV) due to the involvement of sulfur atom. Both crystals display notable birefringence in their respective material classes: 0.275@546 nm and 0.504@546 nm, respectively. X-ray crystallography and computational studies attribute the pronounced birefringence to their π-conjugated moieties and their near-coplanar configu-rations. Comparative analysis of FAHC_(2)O_(4) and FAH_(2)C_(3)N_(3)S_(3) further establishes that the hydrogen bond strength directly influences the molecular coplanarity degree. These findings provide new insights for applying the donor-acceptor hydrogen bonding strategy in the rational design of high-performance birefringent materials. 展开更多
关键词 BIREFRINGENCE Hydrogen bond Coplanarity Formamidinium π-Conjugated unit
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ON INFORMATION THEORY METHOD FOR RELIABILITY ASSESSMENT OF SYSTEMS CONSISTING OF DIFFERENT SUCCESS FAILURE MODEL UNITS 被引量:1
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作者 孙有朝 施军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期129-133,共5页
Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synt... Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models. 展开更多
关键词 information theory information quantity success failure model units reliability assessment approximate lower limit
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Paleo-environmental and geological characteristics of Wufeng-Longmaxi marine shale in different paleo-geomorphological units,Eastern Sichuan Basin,China
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作者 Zhanlei Wang Ruiqian Zhao +5 位作者 Licheng Yang Hongchuan Yin Wen Tang Dongxi Liu Yifan Gu Yuqiang Jiang 《Natural Gas Industry B》 2025年第5期572-584,共13页
The Wufeng-Longmaxi marine shale in the Eastern Sichuan Basin is the key target for shale gas exploration in China.Based on logging response and lithofacies type,three paleo-geomorphological units are identified in th... The Wufeng-Longmaxi marine shale in the Eastern Sichuan Basin is the key target for shale gas exploration in China.Based on logging response and lithofacies type,three paleo-geomorphological units are identified in the deep-water shelf during the Wufeng-Longmaxi deposition:subaqueous slope(SS),subaqueous plain(SP),and subaqueous sub-sag(SSS).Using methods such as mercury intrusion porosimetry(MIP),field emission scanning electron microscopy(FE-SEM),nuclear magnetic resonance(NMR),and X-ray diffraction(XRD),the differences of environmental conditions,mineral composition,organic matter(OM)content,and pore structure in different units are determined,and the factors controlling the differences in shale reservoirs are discussed.The results show that redox conditions of bottom water and productivity of surface water affect OM enrichment,resulting in SSS being the most organic-rich unit.Terrigenous detrital input affects mineral composition in different units,and SSS is the most quartz-rich unit.From SS to SSS shale,the proportion of OM pores gradually increased,while the proportion of inorganic pores and microfractures gradually decreased.The pore size distribution dominated by mesopores in SP and SSS shale is generally consistent,much higher than in SS.The differences in sedimentary environments result in differences in reservoir quality.The OM and brittle mineral content in SSS are relatively high,which is beneficial for reservoir development.SSS has the best environmental conditions;therefore,the quality of the marine shale reservoirs formed is the best. 展开更多
关键词 Eastern Sichuan Basin Marine shale Organic matter Paleo-geomorphological unit Pore structure Wufeng-Longmaxi Formation
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Hybrid deep learning framework with spatiotemporal pattern extraction for decant oil solid content soft sensor development in fluid catalytic cracking units
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作者 Nan Liu Chun-Meng Zhu +3 位作者 Yu-Hui Li Yun-Peng Zhao Xiao-Gang Shi Xing-Ying Lan 《Petroleum Science》 2025年第7期3042-3055,共14页
Coking at the fractionating tower bottom and the decant oil circulation system disrupts the heat balance,leading to unplanned shutdown and destroying the long period stable operation of the Fluid Catalytic Cracking Un... Coking at the fractionating tower bottom and the decant oil circulation system disrupts the heat balance,leading to unplanned shutdown and destroying the long period stable operation of the Fluid Catalytic Cracking Unit(FCCU).The FCCU operates through interconnected subsystems,generating high-dimensional,nonlinear,and non-stationary data characterized by spatiotemporally correlated.The decant oil solid content is the crucial indicator for monitoring catalyst loss from the reactor-regenerator system and coking risk tendency at the fractionating tower bottom that relies on sampling and laboratory testing,which is lagging responsiveness and labor-intensive.Developing the online decant oil solid content soft sensor using industrial data to support operators in conducting predictive maintenance is essential.Therefore,this paper proposes a hybrid deep learning framework for soft sensor development that combines spatiotemporal pattern extraction with interpretability,enabling accurate risk identification in dynamic operational conditions.This framework employs a Filter-Wrapper method for dimensionality reduction,followed by a 2D Convolutional Neural Network(2DCNN)for extracting spatial patterns,and a Bidirectional Gated Recurrent Unit(BiGRU)for capturing long-term temporal dependencies,with an Attention Mechanism(AM)to highlight critical features adaptively.The integration of SHapley Additive exPlanations(SHAP),Complementary Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN),2DCNN,and expert knowledge precisely quantifies feature contributions and decomposes signals,significantly enhancing the practicality of risk identification.Applied to a China refinery with processing capacity of 2.80×10^(6) t/a,the soft sensor achieved the R^(2) value of 0.93 and five-level risk identification accuracy of 96.42%.These results demonstrate the framework's accuracy,robustness,and suitability for complex industrial scenarios,advancing risk visualization and management. 展开更多
关键词 Fluid catalytic cracking unit Soft sensor Deep learning Shapley value Risk identification
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Efficient Transfer of Patients with Critical Illnesses from General Wards to Intensive Care Units
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作者 Chien-Ming Tsao Tzu-Tsui Tsao 《Open Journal of Nursing》 2025年第1期67-77,共11页
Transferring patients with critical illnesses from general wards to intensive care units (ICUs) is a crucial and time-sensitive process. This article presents strategies for improving the efficiency of patient transfe... Transferring patients with critical illnesses from general wards to intensive care units (ICUs) is a crucial and time-sensitive process. This article presents strategies for improving the efficiency of patient transfers, particularly in hospitals where intensive care units are located in buildings separate from general wards. Patient transfers comprise several steps: physicians issue orders, relatives are notified, equipment is prepared, and medical staff coordinate. We identified three factors that influence transfer time: preparation time for bed transfer, time required for shift handovers, and time required for between-ward patient movement. Unfamiliarity with transfer routes and long elevator wait times were factors that also influenced transfer time. The following strategies were proposed: develop a standardized material checklist, design key notes for patient transfers, and optimize transfer routes. These strategies reduced transfer times by 40% to 43%. This study demonstrates that by addressing logistical challenges and streamlining relevant procedures, hospitals can enhance safety and quality of care during patient transfers. 展开更多
关键词 Critical Illnesses Intensive Care Unit (ICU) Patient Safety Time Management Transfer Process Optimization Patient Transfer
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Factors influencing parental presence in neonatal units:A systematic review
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作者 Anais Marie Bérengère François-Garret +5 位作者 Ambre Filippi Sergio Eleni Dit Trolli Florence Casagrande Jean-Baptiste Lotte Isabelle Guellec Arnaud Fernandez 《World Journal of Clinical Pediatrics》 2025年第4期483-492,共10页
BACKGROUND Parental presence in neonatal units(NUs)is essential for infant development and family well-being.A deeper understanding of the factors influencing parental presence is vital and will contribute to the deve... BACKGROUND Parental presence in neonatal units(NUs)is essential for infant development and family well-being.A deeper understanding of the factors influencing parental presence is vital and will contribute to the development of targeted interventions and policies that enhance parental engagement in neonatal care,thereby improving outcomes for infants and their families.AIM To identify and analyze primary factors influencing parental involvement in their child’s care in a neonatal intensive care unit(NICU).METHODS A literature search was conducted using the PubMed,MEDLINE,and Cochrane Library for systematic reviews databases,with the following search terms:“parental presence neonatology”,“couplet care”,“zero separation neonatal care”,“family integrated care”,“couplet care intervention”,“mother-child separation”,“parents newborn togetherness”,“mother-baby care”,“closeness and separation NICU”,“mother-infant interaction NICU”,“kangaroo care”,“dyad mother-infant”,and“newborn integrated care”.The database search for this literature review began on December 10,2024,with the final search conducted on April 10,2025.RESULTS The literature search yielded 281 articles,out of which 23 were selected for a detailed review.The factors associated with parental presence in NUs were grouped into five main categories:Parents’socio-demographic and cultural traits;the physical layout and care model of the NUs;the quality of parents’relationships with the healthcare staff;their active involvement in neonatal care;and the newborn’s health status.CONCLUSION The identification of factors that affect parental presence in NUs is critical for developing effective strategies aimed at encouraging increased parental involvement and ultimately improving neonatal and family outcomes. 展开更多
关键词 Parental presence Neonatal intensive care unit NEONATOLOGY Couplet care Kangaroo care Family-centered care Parental involvement Infant development Zero separation
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On units combination and commitment optimization for electric power production 被引量:1
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作者 谭忠富 何永秀 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第1期12-18,共7页
Electric power system is one of the most important and complex engineering in modern society, supplying main and general power for social production and social life. Meanwhile, since it is a productive system with bo... Electric power system is one of the most important and complex engineering in modern society, supplying main and general power for social production and social life. Meanwhile, since it is a productive system with both high input and output, it has an obvious economic significance to improve its operating efficiency. For an example, an unit is 10 GW scale, if its standard coal consumption can be decreased with 1 g/kW·h, it can save about 5 000 tons standard coal per year. It will be discussed mainly that how to establish optimization model and its numerical algorithm for operating management of the electric power system. The idea on establishing optimization model is how to dispatch work state of units or power plants, so that total cost of fuel consumption for generation is reduced to the minimum. Here the dispatch is to decide which unit or plant to operate, which unit or plant to stop running, how much power should be generated for those operating units or plants at each given time interval. 展开更多
关键词 units combination units commitment OPTIMIZATION plants combination interconnection system
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初二英语(Go for it)Units4—6重难点解析 被引量:1
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作者 卢爱龙 《中学生英语(初中版)》 2004年第10期16-17,共2页
关键词 初二 英语 《Go for it》 units4-6 学习难点 学习重点 词汇 语法
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初中英语第二册(上)同步检测题(Units7—10) 被引量:1
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作者 胡发高 《中学英语园地(初中版)》 2003年第10期23-32,共10页
关键词 初中 英语 第二册 上册 同步检测题 units7—10单元 教学
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初二英语Units17—19重难点解析
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作者 刘世一 沈金燕 《中学生英语(初中版)》 2004年第3期20-21,共2页
关键词 初二 英语 units17—19 学习重点 学习难点 知识点 语法 词汇
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初一英语 Units 5—8综合检测题(英文)
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作者 曹雪凌 曹雷凌 《中学生英语(初中版)》 2002年第17期24-26,32,共4页
1.语音与词汇A)找出每组中划线部分读音与其它三个不同的一个单词。
关键词 units 5 综合检测
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Force Distribution Model of Motor Units of Leg Extensor Muscles
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作者 Milenko Milosevic Predrag Nemec +2 位作者 Dragan Zivotic Milos Milosevic Ranko Rajovic 《Journal of Sports Science》 2014年第4期195-199,共5页
The paper aims to defme the lawfulness (model), by which one can reliably estimate the distribution of motor units' force from the moment when leg extensor muscles start to generate the force until the moment when ... The paper aims to defme the lawfulness (model), by which one can reliably estimate the distribution of motor units' force from the moment when leg extensor muscles start to generate the force until the moment when the maximal level is achieved. The study included 110 participants. To assess the contractile characteristics of leg extensors, standardized equipment and standardized isometric test in sitting position with the angle of the knee joint of 125° were used. The participants were instructed to exert their maximal force as quickly as possible. Using descriptive statistics, cluster analysis and fitting the exponential model of the distribution of force of leg extensor motor units in the whole range of force generation is defined. The model has the following form: y = 0.2051e3.3855x, where y is the motor units force expressed in daN (decanewtons), x is the time expressed in s (seconds). It provides an understanding of the control of multivariate motor unit recruitment and distribution of their force during sports movements as well as training programming for the adoption of forms for conlrolling force distribution of motor units, the development of their maximum force and their involvement speed. 展开更多
关键词 Motor units force rate of force development speed of recruitment for motor units the exponential model.
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初二英语(Go for it)Units1—3重难点解析
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作者 卢爱龙 《中学生英语(初中版)》 2004年第9期19-21,共3页
关键词 初二 英语 《Go for it》 units1—3 学习重点 学习难点 词汇 语法
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初一英语(Goforit)Units10—12重难点解析
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作者 卢爱龙 《中学生英语(初中版)》 2004年第12期11-12,共2页
关键词 初一 英语 《GO for it》 units10-12 学习重点 学习难点 词汇 语法
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