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Grain production space reconstruction and land system function tradeoffs in China 被引量:2
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作者 Fei Li Zhangxuan Qin +4 位作者 Xiaolin Liu Zehui Chen Xiaoli Wei Qiumeng Zhang Min Lei 《Geography and Sustainability》 2021年第1期22-30,共9页
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve... Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis. 展开更多
关键词 Land system function TRADEOFFS SYNERGY Grain production space reconstruction Set Pair Analysis
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Effect of Endurance Training on the Autonomic Nervous System Function of Young Male
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作者 Kaixin Tian Jun Qin +4 位作者 Lan Huang Min Long Shiyong Yu Yang Yu Jian Wu 《International Journal of Clinical Medicine》 2014年第19期1189-1199,共11页
In this study, healthy young males were randomized into groups with moderate intensity training (n = 24), high intensity training (n = 24) and utmost intensity training (n = 24). At the end of 8-week training period, ... In this study, healthy young males were randomized into groups with moderate intensity training (n = 24), high intensity training (n = 24) and utmost intensity training (n = 24). At the end of 8-week training period, HRV measurements demonstrated a marked increase of RMSSD (P = 0.003), PNN50 (P = 0.002), HF (P = 0.002), SDNN (P = 0.002) and LF (P = 0.003) in the moderate intensity group and a decreasing tendency in LFn and LF/HF;however, in the utmost intensity group HFn (P = 0.012) decreased prominently while its LF (P = 0.032), LFn (P = 0.039) and LF/HF (P = 0.015) increased significantly. Nevertheless marked changes were not found in the above indexes of the high intensity group. While resting HR of the three groups declined significantly at the end of 8 weeks (P was 0.001, 0.0001 and 0.001 respectively);RMSSD, PNN50, HF, LF and SDNN were significantly higher in the moderate intensity group than in the other two groups (P P = 0.012) was significantly lower but its LFn and LF/HF were markedly higher (P was 0.025 and 0.015 respectively);LF/HF of both the high and utmost intensity group was significantly higher (P was 0.033 and 0.037 respectively). Despite a significant reduction of plasma NE in all the three groups at the end of 8-week training period (P was 0.016, 0, 0.031 respectively), plasma NE level of moderate and high intensity group was much lower than that of the utmost intensity group (P was 0.001, 0 respectively). Utmost and moderate endurance training results in altered sympathetic and parasympathetic balance towards sympathetic dominance and parasympathetic dominance respectively;whereas high intensity endurance training almost has no effect on ANS function. CPT and HUTT reveal the potential danger posed by utmost intensity endurance training. 展开更多
关键词 ENDURANCE Training INTENSITIES AUTONOMIC Nervous system function
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Research and Review on the Development of Mechanical and Electrical Integration of System Function Principle and Related Technologies
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作者 Zhihai Zhou 《International Journal of Technology Management》 2015年第10期137-139,共3页
关键词 机电一体化系统 现代科学技术 功能原理 微电子技术 机械行业 计算机技术 生产方式 管理体制
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Functional Confirmation Using a Medical X-Ray System of a Semiconductor Survey Meter
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作者 Katsunao Suzuki Toru Negishi +2 位作者 Yoh Kato Yasuhisa Kono Michiharu Sekimoto 《Open Journal of Radiology》 2024年第1期1-13,共13页
In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate ... In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter. 展开更多
关键词 Semiconductor Survey Meter functional Confirmation Medical X-Ray system Calibration Factor Time Constant
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基于自由曲面和L-system的红掌生长模型
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作者 邹一波 褚诗贤 +1 位作者 葛艳 陈明 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期85-90,共6页
针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于... 针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于红掌生长规律的微分L-system,可有效模拟红掌的拓扑结构和生长过程;通过虚拟器官表示红掌器官的几何属性,降低微分L-system的复杂度。试验验证提出的方法对红掌各项生长指标拟合度可达0.89以上,并可对每个生长阶段的红掌进行模拟,能有效地对红掌的生长过程进行建模。 展开更多
关键词 红掌 自由曲面建模 L-system 生长函数 虚拟器官
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Systemic-Functional Grammar and English Extensive Reading
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作者 陈小敏 《海外英语》 2011年第12X期37-38,共2页
Systemic Functional Linguistics is known to people by its special functionalism and social meaning. The study of Systemic Functional Linguistics is also accepted by more and more people. In addition, it means a lot to... Systemic Functional Linguistics is known to people by its special functionalism and social meaning. The study of Systemic Functional Linguistics is also accepted by more and more people. In addition, it means a lot to the learning of lexis, English writing and extensive reading. 展开更多
关键词 systemic-functional GRAMMAR ENGLISH learning EXTENSIVE READING
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Application of Systemic-Functional Grammar in Reading Teaching
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作者 巩茗珠 《疯狂英语(理论版)》 2016年第4期45-46,49,共3页
Based on M.A.K.Halliday's systemic-functional grammar,the paper puts forward some ideas on how to develop reading skills,analyzing how the ideational,interpersonal and textual functions are reflected and their int... Based on M.A.K.Halliday's systemic-functional grammar,the paper puts forward some ideas on how to develop reading skills,analyzing how the ideational,interpersonal and textual functions are reflected and their interrelationship in reading materials,with an attempt to improve the reading ability. 展开更多
关键词 systemic-functional GRAMMAR Reading skills
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The Application of Systemic-Functional Linguistics in Discourse Analysis
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作者 王斌花 《海外英语》 2013年第20期241-243,共3页
Systemic-functional linguistics considers function and semantics as the basis of human language and communicative activity. In recent years, Systemic-functional linguistics has been applied in such areas as natural la... Systemic-functional linguistics considers function and semantics as the basis of human language and communicative activity. In recent years, Systemic-functional linguistics has been applied in such areas as natural language processing, early language learning, language education, stylistics, foreign language teaching, translation and stylistics. It sheds new light on the further application of this linguistic theory in other fields. 展开更多
关键词 systemic-functional LINGUISTICS functionAL linguis
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The Jaffa Transform for Hessian Matrix Systems and the Laplace Equation
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作者 Daniel A. Jaffa 《Journal of Applied Mathematics and Physics》 2024年第1期98-125,共28页
Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of ... Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of linear second-order partial differential equations. This paper discusses the Hessian and its applications in optimization, and then proceeds to introduce and derive the notion of the Jaffa Transform, a new linear operator that directly maps a Hessian square matrix space to the initial corresponding scalar field in nth dimensional Euclidean space. The Jaffa Transform is examined, including the properties of the operator, the transform of notable matrices, and the existence of an inverse Jaffa Transform, which is, by definition, the Hessian matrix operator. The Laplace equation is then noted and investigated, particularly, the relation of the Laplace equation to Poisson’s equation, and the theoretical applications and correlations of harmonic functions to Hessian matrices. The paper concludes by introducing and explicating the Jaffa Theorem, a principle that declares the existence of harmonic Jaffa Transforms, which are, essentially, Jaffa Transform solutions to the Laplace partial differential equation. 展开更多
关键词 Hessian Matrices Jacobian Matrices Laplace Equation Linear Partial Differential Equations systems of Partial Differential Equations Harmonic functions Incompressible and Irrotational Fluid Mechanics
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An Overview of Systematic-Functional Grammar
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作者 瞿冬梅 《海外英语》 2012年第3X期260-262,共3页
The key notions in Halliday's Systematic Grammar and Functional Grammar are first summarized, and then contrasted with Chomsky's Transformational-Generative Grammar. Results show that Systematic-Functional Gra... The key notions in Halliday's Systematic Grammar and Functional Grammar are first summarized, and then contrasted with Chomsky's Transformational-Generative Grammar. Results show that Systematic-Functional Grammar could be viewed as complementa ry to Transformational-Generative Grammar. They combine to reveal the whole picture of language. 展开更多
关键词 systemIC GRAMMAR functionAL GRAMMAR TRANSFORMATION
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 LiBiwen ZengXianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]... By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0]. 展开更多
关键词 开拓定理 叠和理论 存在性 正周期解 两斑块扩散时滞竞争系统 功能反应 人口动态
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REFLECTIVE FUNCTION AND PERIODIC SOLUTION OF DIFFERENTIAL SYSTEMS 被引量:7
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作者 Zhou ZhengxinDept.of Math.,College of Science,Yangzhou Univ.,Yangzhou 225002. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期13-23,共11页
This article deals with the reflective function of the mth-order nonlinear differential systems.The results are applied to discussing the stability property of periodic solutions of these systems.
关键词 反函数 周期解 稳定性 高阶微分
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Modified scaling function projective synchronization of chaotic systems 被引量:1
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作者 徐玉华 周武能 方建安 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期110-114,共5页
This paper investigates a kind of modified scaling function projective synchronization of uncertain chaotic systems using an adaptive controller.The given scaling function in the new method can be an equilibrium point... This paper investigates a kind of modified scaling function projective synchronization of uncertain chaotic systems using an adaptive controller.The given scaling function in the new method can be an equilibrium point,a periodic orbit,or even a chaotic attractor in the phase space.Based on LaSalle's invariance set principle,the adaptive control law is derived to make the states of two chaotic systems function projective synchronized.Some numerical examples are also given to show the effectiveness of the proposed method. 展开更多
关键词 不确定混沌系统 投影同步 缩放功能 同步功能 自适应控制法 修改 混沌吸引子 功能使用
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The Application of Systemic Functional Grammar to the Analysis of Features of American Spokesman’s Language 被引量:1
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作者 李玲玉 《海外英语》 2020年第1期246-247,249,共3页
The spokesman's language is official,flexible and public-oriented,to study how it makes sense through varied linguis-tic function is of great importance.Under the framework of systemic-functional grammar,this thes... The spokesman's language is official,flexible and public-oriented,to study how it makes sense through varied linguis-tic function is of great importance.Under the framework of systemic-functional grammar,this thesis focuses on the linguistic fea-tures of American spokesman's language from perspectives of ideational,interpersonal and textual functions.This thesis includes three parts.Part One introduces background and layout of the study.Part Two is a analysis of America spokesperson's language by SF grammar.Part Three ends with the conclusion. 展开更多
关键词 SPOKESMAN systemic-functional Grammar Linguistic Features
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Systematic analysis of corporate environmental responsibility:elements,structure,function,and principles 被引量:3
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作者 Hong Wang 《Chinese Journal of Population,Resources and Environment》 2016年第2期96-104,共9页
Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustai... Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustainable development.Based on Carroll's pyramid mode of CSR,this article explores the systematic feature of CER.From a systematic perspective,it sorts out its elements,structure,function,and principles of CER.And the four levels of economic,legal,ethical,and charitable structure are emphasized.With these considerations interpreted into practice,success will be achieved in potential cost savings,technological innovation,increased public acceptance,and better relations with governments. 展开更多
关键词 Corporate Social Responsibility(CSR) Corporate Environmental Responsibility(CER) system STRUCTURE function PRINCIPLE
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THE EXISTENCE OF A LIAPUNOV FUNCTIONAL FOR LINEAR DELAY SYSTEM 被引量:1
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作者 ZhangShengxiang ZhengZuxiu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期273-276,共4页
The delay systemx·(t)=Ax(t)+Bx(t-r)is considered. The necessary and sufficient conditions of the existence of a kind of Liapunov functional for the system are given.
关键词 线性时滞系统 泛涵分析 存在性 里亚普诺夫泛涵
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Metaphor in Advertising Language from Systemic Functional Grammar Perspective
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作者 王晓芳 张希永 《海外英语》 2012年第20期259-263,共5页
Metaphor is a common phenomenon in real life.It refers to a figure of speech in which an implied comparison is made between two unlike things that actually have something in common.As for advertising,foreign studies f... Metaphor is a common phenomenon in real life.It refers to a figure of speech in which an implied comparison is made between two unlike things that actually have something in common.As for advertising,foreign studies focus on the analysis of ap plication and effects of metaphor.Based on the historical and current studies on metaphor,this paper aims at analyzing metaphor and its functions in advertising from systemic functional grammar perspective.It pointed out that metaphor,a rhetoric method in advertising language,has many functions,namely,politeness,imagination,subjectivity,objectivity,and textual cohesion,etc.Thus,metaphor can be seen as an important sales strategy,helping the advertisers to establish a good interpersonal relationship with the target audience so as to reach their business aims.In addition,it is also of great importance in that it can stimulate our in terest to learn English,and help us to improve English reading,understanding and writing. 展开更多
关键词 systemIC functionAL GRAMMAR METAPHOR ADVERTISING l
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New WA-system of kravchenko functions in digital signal processing 被引量:1
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作者 V F Kravchenko D V Churikov 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期345-351,共7页
On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.Th... On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.The numerical experiments and physical analysis of the results confirm the efficiency of the proposed WA-systems of Kravchenko functions. 展开更多
关键词 自动化系统 数据处理 数据收集 自动分类
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Construction of Control Lyapunov Functions for a Class of Nonlinear Systems 被引量:5
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作者 CAI Xiu-Shan HAN Zheng-Zhi WANG Xiao-Dong 《自动化学报》 EI CSCD 北大核心 2006年第5期796-799,共4页
The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematica... The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematically via Lyapunov equation. Moreover, by a control Lyapunov function of the feedback linearizable part and a Lyapunov function of the zero dynamics, a control Lyapunov function for the overall nonlinear system is established. 展开更多
关键词 Nonlinear systems control Lyapunov functions semiglobal stabilization zero dynamics.
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Spectrum Characteristics and Transfer Function of the Hydrograph of the Deep Aqueous System 被引量:1
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作者 Chen Baoren, Liu Shuyun, Earth Sciences Dept., Nanjing University, Nanjing, Jiangsu, China Jin Peikang Geological Dept., Tulane University, New Orleans, LA 70118, U.S.A. and Dong Shouyu Hebei Province Seismological Bureau, Shijiazhuang, Hebei, China 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1993年第4期453-464,共12页
The fluctuation of most of the hydrograph in the deep aqueous system records the fluid pulsation in lithosphere and variation of the earth’s crust. Many observations have verified that groundwater is an ideal informa... The fluctuation of most of the hydrograph in the deep aqueous system records the fluid pulsation in lithosphere and variation of the earth’s crust. Many observations have verified that groundwater is an ideal information carrier of the crust. In this paper, the series of input (precipitation, air pressure, Earth tide etc.) and output (water level, artesian flow) of the deep aqueous system are studied by using the spectrum analysis and system theory. The application concepts of transfer function and the spectral structure of the hydrograph enrich the knowledge of the deep aqueous system. Two typical spectral structures of the hydrograph of the deep aqueous system are obtained by comparing with many water-bearing systems of the Jizhong depression. One is from well Ma-17 and the other is from the well Xinze-5. Finally, the physical models of forming the spectrum of the hydrograph are constructed on the basis of the spectrum research on the deep aqueous system. 展开更多
关键词 DEEP AQUEOUS system HYDROGRAPH TRANSFER function
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