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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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Diet and Rat Strain as Factors in Nervous System Function and Influence of Confounders
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作者 S.KACEW R.DIXIT 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第3期203-217,共15页
The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to dev... The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of hurnans. The choice of rats in cognition research studies has specific advantages in that these anirnals possess similar pharrnacodynamic parameters to hurnans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the perforrnance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of thed also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous systern responsivencess of rat strains to chemicals and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessrnent of neurobehavioural functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models. 展开更多
关键词 Diet and Rat Strain as Factors in Nervous system function and Influence of Confounders
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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
In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science an... In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science and technology, it ' s for the penetration and cross of different subjects great push, the more important is caused by technological revolution in the field of engineering and mechanical engineering field under the rapid development of computer technology and microelectronic technology and penetration to the mechanical and electrical integration, which is formed by the mechanical industry lead to trigger a particularly large changes in the mechanical industry management system and mode of production, product and technical structure, composition and function, thus result in industrial production from the previous mechanical electrification progressively electromechanical integration which lead the trend of the current technology. 展开更多
关键词 Mechanical and Electrical Integration system function Development Principle.
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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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Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials
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作者 Changzhong Chen Mingfei Chen Wenliang Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2333-2345,共13页
In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The fu... In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL. 展开更多
关键词 Isogeometric Analysis Sound Transmission Loss Double-Plate system functionally Graded Materials Acoustic Structure Coupling
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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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Generalized system function analysis of resonant behavior of electromagnetic open systems
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作者 LI Long LIU Haixia +1 位作者 SHI Yan LIANG Changhong 《Science in China(Series F)》 2005年第5期615-631,共17页
Abstract The generalized system function, H(s), directly associated with the radiated or scattered fields is presented to effectively analyze the special resonant behavior of electromagnetic open systems in this pap... Abstract The generalized system function, H(s), directly associated with the radiated or scattered fields is presented to effectively analyze the special resonant behavior of electromagnetic open systems in this paper, which is adaptively constructed by using the model-based parameter estimation (MBPE) technique in the complex frequency domain. By analyzing the characteristics of complex zeros, poles and residues of H(s) in a finite operational frequency band, we can effectively determine resonant frequencies and resonant intensity of electromagnetic open systems. It is known that an analysis of Q-factor of antenna and scattering systems has been an interesting and challenging problem. Based on H(s) and the complex frequency w theories, a complex frequency method for Q-factor of electromagnetic open systems is presented in this paper. Some examples of the practical antenna arrays are given to illustrate the applications and validity of the generalized system function theory proposed by this paper. 展开更多
关键词 Keywords: generalized system function H(s) electromagnetic open resonance complex frequency qualityfactor Q model-based parameter estimation (MBPE)
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Using the system function to analyze the performance of transducer's impedance measurement method
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作者 LI Haifeng ZENG Juan +3 位作者 GAO Tianfu LIU Haijun PENG Dayong ZHAO Wenyao 《Chinese Journal of Acoustics》 2013年第3期211-221,共11页
Prom investigation of the advantages and disadvantages of conventional tri-voltage method,a method for the measurement of the transmitting transducer's impedance was presented to solve the difficult problem of examin... Prom investigation of the advantages and disadvantages of conventional tri-voltage method,a method for the measurement of the transmitting transducer's impedance was presented to solve the difficult problem of examining the consistency of the transmitting phased array on the single-mode excitation sea spot.In the method based on the system function, the circuit structure of tri-voltage method was used but new parameters were measured.The principle of the method was given first.Then when resistors with different nominal values were used in the circuit,the measured results for the impedance of transducers were reported.The results were compared with the higher precision impedance analyzer.Finally,the error analysis was performed according to the impedance formula and the equivalent circuit parameters were fitted.Under the condition of guaranteeing the sampling precision,by performance analyzing, the resistor value in series was chosen relatively smaller than the impedance of transducer,the measurement of impedance could achieve the same precision as the higher precision impedance analyzer.Finally,the least squares curve-fitting of measured curves indicated that the transducer equivalent electrical parameters could be extracted accurately and used to design the matching network. 展开更多
关键词 Using the system function to analyze the performance of transducer’s impedance measurement method
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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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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 responsex [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 responsex [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 periodic solutions competition diffusive system functional response continuation theorem of coincidence degree topological degree.
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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 higher-order system reflective function periodic solution stability.
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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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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 poin... 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 chaotic system function projective synchronization scaling function
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Static/dynamic Analysis of Functionally Graded and Layered Magneto-electro-elastic Plate/pipe under Hamiltonian System 被引量:1
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作者 代海涛 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2008年第1期35-42,共8页
The 3-dimensional couple equations of magneto-electro-elastic structures are derived under Hamiltonian system based on the Hamilton principle. The problem of single sort of variables is converted into the problem of d... The 3-dimensional couple equations of magneto-electro-elastic structures are derived under Hamiltonian system based on the Hamilton principle. The problem of single sort of variables is converted into the problem of double sorts of variables, and the Hamilton canonical equations are established. The 3-dimensional problem of magneto-electro-elastic structure which is investigated in Euclidean space commonly is converted into symplectic system. At the same time the Lagrange system is converted into Hamiltonian system. As an example, the dynamic characteristics of the simply supported functionally graded magneto-electro-elastic material (FGMM) plate and pipe are investigated. Finally, the problem is solved by symplectic algorithm. The results show that the physical quantities of displacement, electric potential and magnetic potential etc. change continuously at the interfaces between layers under the transverse pressure while some other physical quantities such as the stress, electric and magnetic displacement are not continuous. The dynamic stiffness is increased by the piezoelectric effect while decreased by the piezomagnetic effect. 展开更多
关键词 functionally graded magneto-electro-elastic material Hamiltonian system symplectic algorithm
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Systematic analysis of corporate environmental responsibility:elements,structure,function,and principles 被引量:4
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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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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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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 delay system Liapunov functional all-delay stability.
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