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FIRST LANGUAGE ACQUISITION AS A MODEL FOR SECOND LANGUAGE ACQUISITION: THE TOTAL PHYSICAL RESPONSE APPROACH IN SECOND LANGUAGE LEARNING AND TEACHING 被引量:11
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作者 井卫华 《外语与外语教学》 1988年第2期12-22,共11页
L1 and L2 acquisition, in some respects, are similar. Language development in children goes hand in hand with physical and cognitive development. Children learn their first language by imitation, but not always and no... L1 and L2 acquisition, in some respects, are similar. Language development in children goes hand in hand with physical and cognitive development. Children learn their first language by imitation, but not always and not only by imitation. There seems to be some "innate capacities" that make children start to speak at the same time they do and in the way they do it. Adults learning a second language usually are controlled more by their motivation. But language input is important for both L1 and L2 acquisition. Though there are differences between CL1 and between CL2 and AL2, the way in which these learners acquire some of the grammatical morphemes is similar. This, together with some other evidence, shows that it is not only children who can acquire language. Adults can also acquire a language. But when adults acquire a language, they should also learn it. Some of the ways in which children acquire their language can be used as a model for L2 acquisition, even for Chinese students whose language is unrelated to English and whose culture is different. Learning the culture of the English-speaking countries will benefit the learning of the language. Like children, listening should also be well in advance of speaking in L2 acquisition. To train listening comprehension skills, Asher’s TPR approach proves more effective. TPR approach is at the moment limited to the beginning stage only. In order for students to gain all the five skills in a second language learning, namely, listening, speaking, reading, writing, and interpreting/translating, other methods should be used at the same time, or at later stages. 展开更多
关键词 THE TOTaL PHYSICaL RESPONSE aPPROaCH IN SECOND LaNGUaGE LEaRNING aND TEaCHING FIRST LaNGUaGE aCQUISITION aS a model FOR SECOND LaNGUaGE aCQUISITION TOTaL
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A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation 被引量:7
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作者 Qiang LI and Yongbo XU(State Key Laboratory for Fatigue and Fracture of Materials, Institute of Metal Research, Chinese Academy of Sciences,Shenyang 110015, China) To whom correspondence should be addressed Present address: Analysis Cener, School of Mater 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第5期435-438,共4页
Recrystallized grains, less than 200 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high... Recrystallized grains, less than 200 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high purity aluminum by ECAE at ambient temperature. The experimental results showed that high strain rate and large deformation could induce dynamic recrystallization.Based on dislocation dynamics and grain orientation change enhanced by plastic deformation,a model for the recrystallization process is developed. The model is used to explain the ultra fine grains which are formed at a temperature still much lower than that for the conventional recrystallization 展开更多
关键词 FIGURE a model of Dynamic Recrystallization in alloys during High Strain Plastic Deformation
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A model for predicting SST in limited region-I. The dynamical equations 被引量:1
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作者 Wang Sizhen Su Yusong Ocean University of Qingdao, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期47-55,共9页
-Starting from physical oceanology characteristics of the China seas and for the short-term operational prediction of SST in the region, a two-dimensional (vertically integrated) primitive equation model, physically r... -Starting from physical oceanology characteristics of the China seas and for the short-term operational prediction of SST in the region, a two-dimensional (vertically integrated) primitive equation model, physically reasonable and operationally feasible,on the upper mixed layer is constructed and given here, which consists of three parts, the nondivergent residual current (the monthly mean field of the Kuroshio and its branches) equations, the dynamic forecasting equations, and the equation of model's physics consisting of surface heat flux, coolings of the upper mixed layer due to the Ekman pumping and the entrainment by gale. This model may be used primarily to forecast the sea surface temperature, and to give estimations of the mean wind-driven current and the sea level, for a period of 3-5 d. In part 1 of this series, the physical conditions for establishing model equations are discussed first, that is, 1. the existence of the upper well mixed layer in the region; 2. the distinguishability of currents of all kinds; 3. the splitting of thermodynamical equation. The equations of nondivergent residual current, and the dynamic forecasting equations with initial values and boundary conditions are also discussed. 展开更多
关键词 SST The dynamical equations a model for predicting SST in limited region-I
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Galantamine protects against beta amyloid peptide-induced DNA damage in a model for Alzheimer's disease 被引量:1
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作者 Willian O.Castillo Andres Felipe Aristizabal-Pachon 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第6期916-917,共2页
Alzheimer’s disease(AD)is the most common type of dementia in elderly population.With a growing aging population not only in the United States but also in the worldwide,AD constitutes an emergent public health prob... Alzheimer’s disease(AD)is the most common type of dementia in elderly population.With a growing aging population not only in the United States but also in the worldwide,AD constitutes an emergent public health problem. 展开更多
关键词 DNa Galantamine protects against beta amyloid peptide-induced DNa damage in a model for alzheimer’s disease aChE
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Use of sensory substitution devices as a model system for investigating cross-modal neuroplasticity in humans 被引量:1
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作者 Amy C.Nau Matthew C.Murphy Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第11期1717-1719,共3页
Blindness provides an unparalleled opportunity to study plasticity of the nervous system in humans.Seminal work in this area examined the often dramatic modifications to the visual cortex that result when visual input... Blindness provides an unparalleled opportunity to study plasticity of the nervous system in humans.Seminal work in this area examined the often dramatic modifications to the visual cortex that result when visual input is completely absent from birth or very early in life(Kupers and Ptito,2014).More recent studies explored what happens to the visual pathways in the context of acquired blindness.This is particularly relevant as the majority of diseases that cause vision loss occur in the elderly. 展开更多
关键词 Use of sensory substitution devices as a model system for investigating cross-modal neuroplasticity in humans BOLD
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Prediction and Analysis of O3 Based on the ARIMA Model 被引量:2
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作者 FENG Dengchao LIANG Lishui LI Chunjiao 《Instrumentation》 2017年第2期44-52,共9页
Despite of the small amount in the atmosphere,ozone is one of the most critical atmospheric component as it protects human beings and any other life on the earth from the sun's high frequency ultraviolet radiation... Despite of the small amount in the atmosphere,ozone is one of the most critical atmospheric component as it protects human beings and any other life on the earth from the sun's high frequency ultraviolet radiation. In recent decades,the global ozone depletion caused by human activities is w ell know n and produces an " ozone hole",the most direct consequence of w hich is the increase in ultraviolet radiation,w hich w ill affect human survival,climatic environment,ecological environment and other important adverse impacts. Due to the implementation of the M ontreal protocol and other agreement,the total amount of ozone depleting substance in the atmosphere has been prominent reduced,w hich w ill lead to a new round of regional climate change.Therefore,predicting the changes of the total ozone in the future w ill have an important guiding significance for predicting the future climate change and making reasonable measures to deal w ith the climate change. In this paper,based on the ozone data of 1979 to 2016 in the southern hemisphere and ARIM A model algorithm,using time series analysis,w e obtain prediction effect of ARIM A model is good by Ljung-Box Q-test and R^2,and the model can be used to predict the future ozone change. With the help of SPSS softw are,the future trend of the total ozone can be predicted in the future 50 years. Based on the above experiment results,the global ozone change in the future 50 years can be forecasted,namely the atmospheric ozone layer w ill return to its 1980's standard by the middle of this century at the global scale. 展开更多
关键词 OZONE Ozone Hole aRIM a model Prediction analysis
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A Model Comparison Study of Fragment Production in 140 A MeV 58,64Ni+9Be Reactions
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作者 马春旺 张艳丽 +1 位作者 王闪闪 乔春源 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期29-33,共5页
The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion... The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion- ablation (SAA) model, and the empirical EPAX2/EPAX3 formulae. The Gogny-gO interaction is taken as the effective nucleon-nucleon interaction in the AMD calculation, and the decays of fragments obtained from the AMD results are calculated by using the GEMINI code. The calculated cross sections of fragments are compared. 展开更多
关键词 BE a model Comparison Study of Fragment Production in 140 a MeV REaCTIONS aMD NI
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The Drosophila adult neuromuscular junction as a model for unravelling amyloid peptide influence on synapse dynamics
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作者 Begona López-Arias Ignacio Monedero +1 位作者 Enrique Turiégano Laura Torroja 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期1987-1989,共3页
Amyloid peptide(Aβ)oligomers are considered one of the primary causal factors for the synaptic loss characteristic of Alzheimer’s disease(AD)(Karran and De Strooper,2016).However,Aβis generated in normal brai... Amyloid peptide(Aβ)oligomers are considered one of the primary causal factors for the synaptic loss characteristic of Alzheimer’s disease(AD)(Karran and De Strooper,2016).However,Aβis generated in normal brains and accumulates at synaptic sites,which raises the question whether Aβplays a physiological role in synapses. 展开更多
关键词 The Drosophila adult neuromuscular junction a model for unravelling amyloid peptide influence synapse dynamics
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Formation Mechanism of the Tongyu Gold Deposit,Shaanxi——A Discussion of a Model for the Formation of Syntectonic Gold Deposits
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作者 Hu Zhengguo Qian Zhuangzhi Xi’an College of Geology, Xi’an 710054, Shaanxi Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第4期409-425,464,共18页
The formation of the Tongyu gold deposit, controlled by regional polyphase deformation-metamorphism.is closely related to the regional composite antiform-shear slip fracture zone. Late-stage reworking of theTaihua Gro... The formation of the Tongyu gold deposit, controlled by regional polyphase deformation-metamorphism.is closely related to the regional composite antiform-shear slip fracture zone. Late-stage reworking of theTaihua Group accounts for the enrichment of ore substances. It is a typical syntectonic gold deposit. The formation and evolution of the deposit involved four stages: (Ⅰ) the state of preparation of ore sub-stances, in which primary source beds originated: (Ⅱ) the stage of remobilization of ore substances, in whichregional progressive metamorphism and migmatization and thermodynamic-chemical differentiation led toremobilization of gold and its initial local concentration: (Ⅲ) the stage of gold deposit formation, in which re-gional folding produced concordant and cross shear-slip fractures and under the dynamic action gold was sepa-rated and migrated in a certain direction and concentrated to form a gold deposit: (Ⅳ) the stage ofsuperpositon, reworking and exposure of orebodies, in which the block uplifted and the deposit againunderwent reworking through faulting and mechanical differentiation.Thermodynamic mineralization played adominant role in the formation of the deposit. 展开更多
关键词 a Discussion of a model for the Formation of Syntectonic Gold Deposits Formation Mechanism of the Tongyu Gold Deposit Shaanxi Gold
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A model for the response of wave directions in slowly turning wind fields
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作者 Li Luping and Gong Ein First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期499-508,共10页
On the basis of the wave energy balance equation, the response model of mean directions of locally wind-generated waves in slowly turning wind fields has been derived. The results show that in a homogeneous field, the... On the basis of the wave energy balance equation, the response model of mean directions of locally wind-generated waves in slowly turning wind fields has been derived. The results show that in a homogeneous field, the time scale of the response is not only related to the rate of wave growth, but also to the directional energy distribution and the angle between the wind direction and the mean wave direction. Furthermore, the law of change in the mean wave direction has been derived. The numerical computations show that the response of wave directions to slowly turning wind directions can be treated as the superposition of the responses of wave directions to a series of sudden small-angle changes of wind directions and the turning rate of the mean wave direction depends on the turning rate and the total turning angles of the wind direction. The response of wave directions is in agreement with the response for a sudden change of wind directions if the change in wind directions is very fast. Based on the normalized rates of wave growth under local winds presented by Wen et al. (1989), a quantitative estimate of the time scale of the response shows that the relationships between the dimensionless time scale and both the dimensionless total wave energy and the dimensionless peak frequency agree fairly well with the observations in comparison with other models. 展开更多
关键词 WaVE a model for the response of wave directions in slowly turning wind fields
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The rat model of placental ischemia as a model of postpartum posterior cortical atrophy?
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作者 Ashtin B.Giambrone Junie P.Warrington 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2094-2095,共2页
Potential link between preeclampsia(PE)and posterior cortical atrophy(PCA):PCA is a neurodegenerative disorder affecting the parietal,occipital,and occipital-temporal brain regions,often manifesting as a decline ... Potential link between preeclampsia(PE)and posterior cortical atrophy(PCA):PCA is a neurodegenerative disorder affecting the parietal,occipital,and occipital-temporal brain regions,often manifesting as a decline in visual processing and perception skills in affected individuals. 展开更多
关键词 The rat model of placental ischemia as a model of postpartum posterior cortical atrophy PE
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From neurogenesis to neuronal regeneration: the amphibian olfactory system as a model to visualize neuronal development in vivo
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作者 Ivan Manzini 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第6期872-874,共3页
How do individual neurons develop and how are they in- tegrated into neuronal circuitry? To answer this question is essential to understand how the nervous system develops and how it is maintained during the adult li... How do individual neurons develop and how are they in- tegrated into neuronal circuitry? To answer this question is essential to understand how the nervous system develops and how it is maintained during the adult life. A neural stem cell must go through several stages of maturation, including proliferation, migration, differentiation, and integration, to become fully embedded to an existing neuronal circuit. The knowledge on this topic so far has come mainly from cell culture studies. Studying the development of individual neurons within intact neuronal networks in vivo is inherently difficult. Most neurons are generated form neural stem cells during embryonic and early postnatal development. 展开更多
关键词 the amphibian olfactory system as a model to visualize neuronal development in vivo FIGURE
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Construction of a model of autologous blood intracerebral hemorrhage in rats with a double injection and double needle withdrawal and the characteristics of the operative technique
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作者 Siyi Yin Zhenhui Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期355-357,共3页
BACKGROUND : Experimental animal models of intracerebral hemorrhag (ICH) are greatly needed, so the process of establishment should be ideal in hematoma formation and easy to operate. OBJECTIVE : To construct mode... BACKGROUND : Experimental animal models of intracerebral hemorrhag (ICH) are greatly needed, so the process of establishment should be ideal in hematoma formation and easy to operate. OBJECTIVE : To construct model of ICH in rats with double injection of autologous blood taken from the cut tail cut and double withdrawal of the needle (shortened as two-step injection model), and compare with those induced by single and double injections. DESIGN : A randomized controlled tria SETTING: Department of Neurology, General Hospital of Military Area Command of Chinese PLA. MATERIALS: Thirty male Wistar rats of 10 to 12 months, weighing (400±25) g, provided by the Experimental Center of Medical Animals, General Hospital of Shenyang Military Area Command of Chinese PLA, were divided randomly into 3 groups with 10 rats in each group: two-step injection group, single injection group, double injection group. METHODS : The experiment was carried out in the Department of Neurology, General Hospital of Military Area Command of Chinese PLA from March to June in 2004. Autologous blood ICH model in rats were established as follows: In the two-step injection group, 50 μL unclotted autologous blood was taken from the rat tail cut, then injected with microsyringe into the caudate nucleus, 10 μL injected at first, paused for 2 minutes, and then the rest 40 μL injected slowly and continuously within 2 minutes. After the injection, the needle was kept immovable for about 4 minutes, withdrawn 2.0 mm, again kept immovable for about 4 minute, and then removed wholly at a slow speed. In the single injection group, 50 μL unclotted tail blood was injected slowly and continuously all within 2 minutes and the needle was slowly removed;(4) In the double injection group, 10 mL blood was injected at first, paused for 2 minutes, the rest 40 μL injected evenly within 2 minutes, and then the needle was withdrawn slowly and uninterruptedly. Neurologic findings were scored in accordance with Longa's five-point scale (0-4 scores, the higher the score, the severer the neurological dysfunction). The rats were killed to remove and sections were prepared, the morphological features of hematomas were grossly observed, the maximal diameter and size of hematomas in each slice were measured with the imaging analytical system, and the volume was calculated. Meanwhile, the conveniences of the techniques were compared. MAIN OUTCOME MEASURES: The morphological features and volume of hematomas, neurologic deficit score (NDS), and the convenience of the techniques were compared. RESULTS: All the 30 rats were involved in the analysis of results without deletion. (1) Results of the morphological observation of volume of hematoma: In the two-step injection group, hematomas located in the right caudate nucleus area regularly in circular or analogously circular shape in each slice. The formation rate of hematomas in the single injection group and double injection group were lower than those in the two-step injection group [60% (6/10), 80% (8/10), 100% (10/10), P〈 0.01, 0.05]. The volume of hematomas in the single injection group and double injection group were smaller than those in the two-step injection group [(28.5±14.8), (33.4±7.4), (41.6±3.9) mm3, P〈 0.01, 0.05]. (2) NDS results: The NDS scores in the single injection group and double injection group were smaller than that in the two-step injection group (0.90±0.83, 1.30±0.78, 1.90±0.57, P〈 0.05). (3)Comparison of the convenience of the techniques: The double injection method allowed generating reproducible hematomas in rats with shortcomings that it needed autologous arterial blood from femoral artery, and precision instruments such as microinfusion pump. The two-step injection injected fresh unclotting blood taken directly from the tail cut with microsyringe into the rat brain, and it has the advantages of easy operation, no influence on the activity of thrombase, shorter duration for model establishment, and higher rate of hematoma formation, which could generate ideal and economical models of ICH. The two-step injection induced hemotoma regularly in circular or analogously circular shape in each slice, but those induced by single and double injections were mostly in strip or fusiform shapes and extending along the needle tracks or into the ventricle or subarachnoid space. CONCLUSION : The autologous blood ICH model induced by the two-step injection method is a reproducible and reliable one in regular shape, which is better than those induced by double and single injections. 展开更多
关键词 Construction of a model of autologous blood intracerebral hemorrhage in rats with a double injection and double needle withdrawal and the characteristics of the operative technique ICH
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A MODEL FOR SIMULATION OF FRICTION PHENOMENON BETWEEN DIES AND WORKPIECE
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作者 罗子健 唐才荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1297-1307,共11页
Based on the interaction of asperities and upperbound approach a mathematical model for simulation of friction phenomenon between dies and workpiece is proposed. Optimizing the mathematical model with respect to sever... Based on the interaction of asperities and upperbound approach a mathematical model for simulation of friction phenomenon between dies and workpiece is proposed. Optimizing the mathematical model with respect to several variables it is found that in addition to adhering, tearing, ploughing, etc., asperities workpiece can move wave-like along the surface layer and under certain circumstances they may disappear. If the asperities wavily move along the surface layer the friction coefficient depends on the geometry of asperities. However, the bonding strength of asperities, has no significant influence on friction coefficient. The depth of the plastic deformation layer is related to the geometry of asperities, too. The soundness of the prerequisite of the proposed model and some analytical results were verified by experiments. 展开更多
关键词 a model FOR SIMULaTION OF FRICTION PHENOMENON BETWEEN DIES aND WORKPIECE
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A model solar energy power plant will be built in Shandong Province
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作者 Liu Chunsheng 《Electricity》 2010年第2期7-,共1页
A US-China jointly owned model solar energy power plant, with an ultimate installed capacity of 2 000 MW, will be built in Shandong Province.
关键词 WILL a model solar energy power plant will be built in Shandong Province
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Evaluation of a model recommended for N fertilizer application in irrigated rice
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作者 ZHENG Zhiming, YAN Lijiao, and WANG Zhaoqian, Agro-ecology Inst, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1997年第3期7-8,共2页
The response of rice to N fertilizer applicationhas shown that high rates of N application donot always ensure a proportional increase inyield due to high N losses. A model, ORYZA-0 was developed by ten Berge for desi... The response of rice to N fertilizer applicationhas shown that high rates of N application donot always ensure a proportional increase inyield due to high N losses. A model, ORYZA-0 was developed by ten Berge for designingoptimum N fertilizer management strategy inrice. We evaluated the performance ofORYZA-0 in Jinhua, Zhejiang Province. ORYZA-0 includes N uptakes, partition-ing of N among the organs, and utilization ofleaf N in converting solar energy to dry mat-ter. It can predict the amount and time of Nfertilizer application to achieve a maximumbiomass or yield combining with Price algo-rithm optimization procedure. 展开更多
关键词 Evaluation of a model recommended for N fertilizer application in irrigated rice
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite Information Quantity Formulating a model Measurement accuracy Limit Objective model Selection
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A Model System of Development Regulated by the Long-distance Transport of mRNA 被引量:12
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作者 David J. Hannapel 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第1期40-52,共13页
BELl-like transcription factors are ubiquitous in plants and interact with KNOTTEDI-types to regulate numerous developmental processes. In potato, the RNA of several BELl-like transcription factors has been identified... BELl-like transcription factors are ubiquitous in plants and interact with KNOTTEDI-types to regulate numerous developmental processes. In potato, the RNA of several BELl-like transcription factors has been identified in phloem cells. One of these, StBEL5, and its Knox protein partner regulate tuber formation by targeting genes that control growth. RNA detection methods and grafting experiments demonstrated that StBEL5 transcripts move across a graft union to localize in stolon tips, the site of tuber induction. This movement of RNA originates in source leaf veins and petioles and is induced by a short-day photoperiod, regulated by the untranslated regions, and correlated with enhanced tuber production. Addition of the StBEL5 untranslated regions to another BELl.like mRNA resulted in its preferential transport to stolon tips leading to increased tuber production. Upon fusion of the untranslated regions of StBEL5 to a β-glucuronidase marker, translation in tobacco protoplasts was repressed by those constructs containing the 3' untranslated sequence. The untranslated regions of the StBEL5 mRNA are involved in mediating its long-distance transport and in controlling translation. The 3' untranslated sequence contains an abundance of conserved motifs that may serve as binding motifs for RNA-binding proteins. Because of their presence in the phloem sieve tube system, their unique untranslated region sequences and their diverse RNA accumulation patterns, the family of BEL1-like RNAs from potato represents a valuable model for studying the long-distance transport of full-length mRNAs and their role in development. 展开更多
关键词 BEL a model System of Development Regulated by the Long-distance Transport of mRNa LONG
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A model for aerosol mass concentration using an optical particle counter 被引量:11
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作者 顾芳 杨娟 +1 位作者 保民 贺安之 《Chinese Optics Letters》 SCIE EI CAS CSCD 2008年第3期214-217,共4页
A model for measuring aerosol mass concentration by an optical particle counter is presented using the conception of the average mass. In this model, to understand the meaning of the pulse height distribution of parti... A model for measuring aerosol mass concentration by an optical particle counter is presented using the conception of the average mass. In this model, to understand the meaning of the pulse height distribution of particles which is used to inverse mass concentration, the relationship among intensity distribution in the optical sensing volume, particle shape, and the pulse height distribution is discussed. To solve the instability of the equivalent factor, a novel two-step calibration method is proposed. The experimental results demonstrate that mass concentrations calculated by the model are in good agreement with those measured by a norm-referenced instrument. For samples of soot and air, the slopes of fitting lines of data points are 0.9582 and 0.9220, and the correlation coefficients are 0.9991 and 0.9965, respectively. 展开更多
关键词 a model for aerosol mass concentration using an optical particle counter OPC
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Comments on the article of “Agriculture Green Development:a model for China and the world” 被引量:2
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作者 Carolien KROEZE 《Frontiers of Agricultural Science and Engineering》 2020年第1期106-107,共2页
The coming century will be one of grand global challenges.We will be facing global warming,a growing world population and growing economies.To meet the needs of all world citizens in a sustainable way will not be easy... The coming century will be one of grand global challenges.We will be facing global warming,a growing world population and growing economies.To meet the needs of all world citizens in a sustainable way will not be easy.One of the challenges will be to feed the growing world population,while limiting global warming.Food and water security are at risk,and we will need to invest in innovative and clean technologies to ensure that also in the future there will be enough food to feed the word.This all is reflected in the UN Sustainable Development Goals. 展开更多
关键词 agriculture Green Development:a model for China and the world Comments on the article of
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