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Some properties of monotone set functions defined by Choquet integral 被引量:4
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作者 欧阳耀 李军 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期423-426,共4页
In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-ad... In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-additivity, strong order continuity, property (s) andpseudomelric generating property, etc., are preserved by the new set function. It is also shown thatC-integrability assumption is inevitable for the preservations of strong order continuous andpseudometric generating property. 展开更多
关键词 non-additive measure monotone set function choquet integral
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Concatenated Trellis Coding and CPM for DS/SSMA Communications in Rayleigh Fading Channel
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作者 仰枫帆 梁树雄 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期9-16,共8页
In this paper, direct sequence spread spectrum multiple access (DS/SSMA) communication system employing serially concatenated trellis coded modulation (TCM) and continuous phase modulation (CPM) over flat Rayleigh fa... In this paper, direct sequence spread spectrum multiple access (DS/SSMA) communication system employing serially concatenated trellis coded modulation (TCM) and continuous phase modulation (CPM) over flat Rayleigh fading channel are presented. The performance of this concatenated TCM/CPM DS/SSMA system is exploited by the theoretical analysis and numerical simulations. The results demonstrate that significant improvements in error probability of this DS/SSMA system over the system with single TCM or CPM of different modulation indices can be achieved under the same conditions. 展开更多
关键词 concatenated TCM/CPM direct sequence spread spectrum multiple access Rayleigh fading channel
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The Sequential Continuity of Multiplication on a Class of Infinite Matrix Algebras
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作者 赵玟亨 刘金霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期49-52,共4页
Let λ and μ are sequence spaces and have both the signed_weak gliding hump property, (λ,μ) be the algebra of the infinite matrix operators which transform λ into μ, in this paper, we study the strong? Mackey... Let λ and μ are sequence spaces and have both the signed_weak gliding hump property, (λ,μ) be the algebra of the infinite matrix operators which transform λ into μ, in this paper, we study the strong? Mackey? weak multiplier sequentially continuous problem of infinite matrix algebras (λ,μ). 展开更多
关键词 sequence spaecs infinite matrix MULTIPLIER sequential continuity
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Genetic programming-based chaotic time series modeling 被引量:1
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作者 张伟 吴智铭 杨根科 《Journal of Zhejiang University Science》 EI CSCD 2004年第11期1432-1439,共8页
This paper proposes a Genetic Programming-Based Modeling (GPM) algorithm on chaotic time series. GP is used here to search for appropriate model structures in function space, and the Particle Swarm Optimization (PSO) ... This paper proposes a Genetic Programming-Based Modeling (GPM) algorithm on chaotic time series. GP is used here to search for appropriate model structures in function space, and the Particle Swarm Optimization (PSO) algorithm is used for Nonlinear Parameter Estimation (NPE) of dynamic model structures. In addition, GPM integrates the results of Nonlinear Time Series Analysis (NTSA) to adjust the parameters and takes them as the criteria of established models. Experiments showed the effectiveness of such improvements on chaotic time series modeling. 展开更多
关键词 Chaotic time series analysis Genetic programming modeling Nonlinear Parameter Estimation (NPE) Particle Swarm Optimization (PSO) Nonlinear system identification
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The Extension of Continuous Measure
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作者 彭祖赠 孙韫玉 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期88-94,共7页
In this paper we give a sufficient and necessary condition under which a continuous measure (whose values belong to, the extended half-line (0,+∞) defined on a class of sets closed under the formation of intersection... In this paper we give a sufficient and necessary condition under which a continuous measure (whose values belong to, the extended half-line (0,+∞) defined on a class of sets closed under the formation of intersection can be extended to a smallest monotone class containing this class, and we also give a condition under which there exists a unique extension. In addition, we give a method by means of which a continuous measure on a monotone class can be extended again. 展开更多
关键词 continuous measure complete partition basic continuous extension
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On Common Fixed Point of Noncompatible Mapping Pairs 被引量:2
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作者 朱元泽 吕中学 《Journal of China University of Mining and Technology》 2002年第1期111-114,共4页
In this paper, two common fixed point theorems for noncompatible maps in a metric space have been proved under the condition of without taking completeness of the space or continuity of the mapings into account. The r... In this paper, two common fixed point theorems for noncompatible maps in a metric space have been proved under the condition of without taking completeness of the space or continuity of the mapings into account. The related common point theorems were improved. 展开更多
关键词 metric space noncompatible maps common fixed point.
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Nitrogen Mineralization in Soils Along a Vegetation Chronosequence in Hong Kong 被引量:5
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作者 L.M.MARAFA K.C.CHAU 《Pedosphere》 SCIE CAS CSCD 2005年第2期181-188,共8页
This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the rel... This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the relationships between N mineralization and successional development of vegetation in the absence of fire. The sites including a newly burnt area (S1), short grassland (S2), tall grassland (S3), mixed tall grassland and shrubland (S4), and woodland (S5) were selected,and the in situ core incubation method was used to estimate nitrogen mineralization. Throughout the 60-day incubation in four periods, more nitrogen was mineralized at the S3 and S4 sites, the predominantly grassland sites, which contained the highest levels of soil organic matter (SOM) and total Kjeldahl nitrogen (TKN), than the S1 site, while immobilization occurred at the S2 and S5 sites. Leaching loss decreased with successional development of the vegetation, in the order of S1 > S2 > S3 > S4 > S5. The pattern of nitrogen uptake with ecological succession was less conspicuous, being complicated by the immediate effect of fire and possibly the ability of the woodland species to extract nitrogen from the deeper ground.In the absence of fire for 3 to 6 years, the build-up of SOM and TKN was accompanied by active mineralization, thus paving the way for the invasion of shrub and tree species. A close relationship existed between nitrogen mineralization and ecological succession with this vegetation gradient. Inherent mechanisms to preserve nitrogen in a fire-prone environment including immobilization and uptake and the practical relevance of nitrogen mineralization to reforestation are discussed. 展开更多
关键词 fire impact IMMOBILIZATION nitrogen mineralization successional development vegetation chronosequence
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Two-Phased Method for Detecting Evasive Network Attack Channels 被引量:2
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作者 CAO Zigang XIONG Gang +2 位作者 ZHAO Yong GUO Li FANG Binxing 《China Communications》 SCIE CSCD 2014年第8期47-58,共12页
With the rapid developments of information technology,various industries become much more dependent on networks.Driven by economic interests and the game between countries reflected by growing cyberspace confrontation... With the rapid developments of information technology,various industries become much more dependent on networks.Driven by economic interests and the game between countries reflected by growing cyberspace confrontations,evasive network attacks on information infrastructures with high-tech,high concealment and longterm sustainability become severe threats to national security.In this paper,we propose a novel two-phased method for the detection of evasive network attacks which exploit or pretend to be common legal encryption services in order to escape security inspection.Malicious communications which camouflage themselves as legal encryption application are identified in the SSL'session structure verification phase firstly,and then by serverside X.509 certificate based anomaly detection,suspicious attack behaviors are further distinguished effectively.Experiment results show that our method is very useful for detecting the network activities of certain unknown threats or new malwares.Besides,the proposed method can be applied to other similar services easily. 展开更多
关键词 evasiveencryption SSL X.509detectionnetwork attacks CERTIFICATE ANOMALY
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Long Time Series Observations from Antarctica with the International Concordia Explorer Telescope (ICE-T)
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作者 Igor Di Varano 《Journal of Physical Science and Application》 2013年第1期33-37,共5页
The Intemational Concordia explorer telescope (ICE-T) is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wi... The Intemational Concordia explorer telescope (ICE-T) is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wide-fieldwith a total FOV of 65 square degrees. Its aim is to operate at Dome C, the French-Italian Antarctic Station, taking advantage of the long winter night for continuous observations. It is optimized for high precision photometry in two separate filters Sloan g and Sloan i ranging from 100 mmag to 10 mmag (from 9 to16 mag). Among the scientific tasks there are the detection of hot Jupiters and Super Earths with the transit method, and related magnetic activity of the hosting stars. The 4m Radom dome for ICE-T together with 3 foundation pillars and the cables bundle have been already successfully installed in January 2009. 展开更多
关键词 Instrumentation for astronomy ANTARCTICA design in extreme environment.
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A New Class of Generalized Landau Linear Positive Operator Sequence and Its Properties of Approximation
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作者 陈湛本 石济民 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第1期29-43, ,共15页
In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the wh... In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the whole real axis. The properties of approximation are studied and their asymptotic formulae are presented. These results show that their degrees of approximation are the best among existing operator sequences of Landau type, for example, their degrees of approximation for C 2[0, 1] are O(1/n 2) but corresponding degree of ordinary Landau operators are only O(1/n). 展开更多
关键词 generalized Landau linear positive operators degree of approximation asymptotic formula
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Controlling Nonlinear Dynamics in Continuous Crystallizers
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作者 Victoria Gamez-Garcia Eusebio Bolanos-Reynoso +1 位作者 Oscar Velazquez-Camilo Hector Puebla 《Journal of Mathematics and System Science》 2012年第1期45-52,共8页
Crystallization is used to produce vast quantities of materials. For several applications, continuous crystallization is often the best operation mode because it is able to reproduce better crystal size distributions ... Crystallization is used to produce vast quantities of materials. For several applications, continuous crystallization is often the best operation mode because it is able to reproduce better crystal size distributions than other operation modes. Nonlinear oscillation in continuous industrial crystallization processes is a well-known phenomenon leading to practical difficulties such that control actions are necessary. Nonlinear oscillation is a consequence of the highly nonlinear kinetics, different feedbacks between the variables and elementary processes taking place in crystallizers units, and the non-equilibrium thermodynamic operation. In this paper the control of a continuous crystallizer model that displays oscillatory behavior is addressed via two practical robust control approaches: (i) modeling error compensation, and (ii) integral high order sliding mode control. The controller designs are based on the reduced-order model representation of the population balance equations resulting after the application of the method of moments. Numerical simulations show good closed-loop performance and robustness properties 展开更多
关键词 CRYSTALLIZATION continuous crystallization population balances nonlinear dynamics robust model-based control
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Management of Public Finance and Sustainable Growth in a Developing Country: The Case of Cameroon
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作者 ALIMA NDONGO Christine Emestine 《Journal of Mathematics and System Science》 2014年第5期351-357,共7页
This paper studies the efficiency of the public financial management system in a developing country (Cameroon) by using time series data from 2000 to 2012. It shows the impact of characteristics variables of this se... This paper studies the efficiency of the public financial management system in a developing country (Cameroon) by using time series data from 2000 to 2012. It shows the impact of characteristics variables of this sector in the process of sustainable growth. The contribution of these indicators in sustainable development, notably public expenditures, debt servicing or public debt and fiscal revenue is determined by using the Stoehastie Frontier Analysis approach (SFA). A significant connection between public expenditures, debt servicing and sustainable growth ratio is established by the model studied. The research results show an encouraging but low level of efficiency in State financial management policy. Thus, in order to avoid a sovereign debt crisis that developed countries of Europe are facing these current days, some efforts must continue to be done not only to control the public debt, but also for a better allowance of public expenditures and a good collection of State revenue. 展开更多
关键词 EFFICIENCY sovereign debt stochastic frontier analysis sustainable growth.
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The Use of Drones in Forestry 被引量:4
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作者 Tiberiu Paul Banu Gheorghe Florian Borlea Constantin Banu 《Journal of Environmental Science and Engineering(B)》 2016年第11期557-562,共6页
Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that... Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that can be collected flexibly in a short time and at a relatively low price. Also, drones have an important role in filling the gaps of common data collected using manned aircraft or satellite remote sensing, while having many advantages both in research and in various practical applications particularly in forestry as well as in land use in general. This paper aims to briefly describe the different approaches of applications of UAVs (Unmanned Aircraft Vehicles) in forestry, such as forest mapping, forest management planning, canopy height model creation or mapping forest gaps. These approaches have great potential in the near future applications and their quick implementation in a variety of situations is desirable for the sustainable management of forests. 展开更多
关键词 DRONES UAV remote sensing forest management.
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Wavelet Analysis in Volcanology: The Case of Phlegrean Fields
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作者 Giuseppe Pucciarelli 《Journal of Environmental Science and Engineering(A)》 2017年第6期300-307,共8页
The Phlegrean Fields are an area in the west of Naples (Italy), with a huge interest in geophysical community being a volcanic caldera among the most dangerous in the world. Various techniques of monitoring exist. A... The Phlegrean Fields are an area in the west of Naples (Italy), with a huge interest in geophysical community being a volcanic caldera among the most dangerous in the world. Various techniques of monitoring exist. Among all, the control of ground deformations and variations in sea level has considerable importance. Time series of ground deformation and tidal data in this area have been analysed to highlight these important geophysical features and these results are compared with those obtained from similar data in other time periods. With regard to first mentioned, tiltmetric data have been analysed. These ones come from the tiltmeter network sited in Pozzuoli. Instead, the tidal data come from the tide gauge in Pozzuoli. Data have been analysed by means of a wavelet approach, using a Continuos Wavelet Transform and using, as so-called "Wavelet Mother", a Gabor-Morlet wavelet. For each time series, the principal harmonic constituents result: lunar semidiurnal (M2), solar semidiumal (S2) and lunar diurnal (K1). Other harmonic constituents, having frequencies higher than 1/hour, are present.These last ones could be interpreted as seiches and they could be linked up with generation of discrete plumes of rising magma. Frequencies at which there is the occurrence of these seiches are in agreement with previous studies. 展开更多
关键词 Phlegrean Fields wavelet analysis TILTMETER TIDES seiches.
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Knowledge and Social Capital: Drivers for Sustainable Local Growth
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作者 Paola Demartini Mara Del Baldo 《Chinese Business Review》 2015年第2期106-117,共12页
This paper presents a knowledge resources perspective for territorial competitiveness and sustainability. The latter is defined as a pathway promoted by a plurality of public and private actors, in the for-profit and ... This paper presents a knowledge resources perspective for territorial competitiveness and sustainability. The latter is defined as a pathway promoted by a plurality of public and private actors, in the for-profit and non-profit sectors, who find that relationships and social cohesion are the drivers for the construction of shared territorial governance. This study integrates an extensive literature review with data from longitudinal empirical research. Authors have adopted the methodology of qualitative research-based case study. In particular, this paper focused the analysis on a project of territorial governance promoted in the Marches region of Italy. This region was selected as a case study, because it is emblematic of the Italian context; the territory is characterized by small businesses diffused throughout the socio-economic fabric and by the proactive role taken by local governments. The perspective offers a powerful instrument for raising awareness of the gaps that local policymakers should address through their initiatives in the knowledge economy. 展开更多
关键词 KNOWLEDGE social capital sustainable development regional network local growth
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Energy-saving performance investigation on sustainable architecture design of open-plan housing in temperate region
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作者 Haitao Jiang Qichao Ban 《International Journal of Technology Management》 2013年第1期27-30,共4页
With the increasing requirement of a higher living quality and the growing awareness of energy saving, how to improve the indoor comfort level and to reduce the expenditure of energy and slow down the rate of natural ... With the increasing requirement of a higher living quality and the growing awareness of energy saving, how to improve the indoor comfort level and to reduce the expenditure of energy and slow down the rate of natural resource consumption is becoming increasingly important. The theory of open-plan housing is able to provide a more flexible and adaptive space for the users and bring sustainable and economic benefit in the way of making full use of construction materials. Sustainable architecture design, as a method to respond the phenomenon, is able to low down the building' s energy consumption and has enormous potentials in creation of sustainable living environment and a high-quality dwelling condition. The primary aim of this research is to create a new sustainable architecture design method for occupancy by integrating openplan housing theory and application of sustainable technologies. Numerical simulation by computer program is applied in order to investigate and evaluate the possibility of this method in teruas of improving indoor comfort level and energy-saving capacity. 展开更多
关键词 Sustainable architecture design Open-plan housing energy-saving performance Sustainable technology Resource sustainability
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A Comparison of Arithmetic Operations for Dynamic Process Optimization Approach 被引量:3
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作者 洪伟荣 谭鹏程 +1 位作者 王树青 Pu Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期80-85,共6页
A comparison of arithmetic operations of two dynamic process optimization approaches called quasi-sequential approach and reduced Sequential Quadratic Programming(rSQP)simultaneous approach with respect to equality co... A comparison of arithmetic operations of two dynamic process optimization approaches called quasi-sequential approach and reduced Sequential Quadratic Programming(rSQP)simultaneous approach with respect to equality constrained optimization problems is presented.Through the detail comparison of arithmetic operations,it is concluded that the average iteration number within differential algebraic equations(DAEs)integration of quasi-sequential approach could be regarded as a criterion.One formula is given to calculate the threshold value of average iteration number.If the average iteration number is less than the threshold value,quasi-sequential approach takes advantage of rSQP simultaneous approach which is more suitable contrarily.Two optimal control problems are given to demonstrate the usage of threshold value.For optimal control problems whose objective is to stay near desired operating point,the iteration number is usually small.Therefore,quasi-sequential approach seems more suitable for such problems. 展开更多
关键词 dynamic optimization arithmetic operation comparison quasi-sequential approach simultaneous approach
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The Information Risk in the Latest Crisis: A Driver or a Driven Factor for Global Financial Markets Equilibrium?
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作者 Giorgio Bertinetti Guido Max Mantovani 《Journal of Modern Accounting and Auditing》 2012年第5期702-732,共31页
The latest financial crisis has been impressive for strength, impact, duration, and reduced efficacy of the economic and financial policies adopted by the authorities. We use an original information risk model to cont... The latest financial crisis has been impressive for strength, impact, duration, and reduced efficacy of the economic and financial policies adopted by the authorities. We use an original information risk model to contribute to the analysis of the crisis and to suggest some approaches for a possible early diagnosis. Using data referred to the three main financial markets and comparing the latest crisis with the previous one and with long-term quantitative evidence, we find out that the 2007-2009 crisis was very different in the information risk quality. That gap affected the market risk aversion and its equilibrium, reducing the efficacy of the authorities' intervention tools mainly based on payoff risk control and efficient market restoration. Since information risk is an endogenous element of the market dynamics that can be independent form contingent levels of market efficiency. Drivers of information risk in the European Markets differed strongly from the US and Japanese ones; that is why some global decisions had low impact while opportunities of local intervention were missed. 展开更多
关键词 financial crisis information asymmetries risk premium
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Characteristics of Strain Release before Large Earthquakes of M≥7. 0 in the Chinese Mainland
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作者 Jiang Haikun Miao Qingzhuang +3 位作者 Dong Xiang Wu Qiong Li Mingxiao Song Jin 《Earthquake Research in China》 2010年第1期1-12,共12页
The enumerating algorithm has been introduced into the fitting procedure of the ASR model. Based on the detailed study of 21 large earthquakes with M≥6. 8 in the Chinese Mainland,the statistical features of seismic s... The enumerating algorithm has been introduced into the fitting procedure of the ASR model. Based on the detailed study of 21 large earthquakes with M≥6. 8 in the Chinese Mainland,the statistical features of seismic strain release before large earthquakes have been summarized. In the mass,the strain release models can be divided into five types. The first is the DA model,in which the strain release accelerates in broader areas and decelerates in small areas around the epicenter. Approximately 38% of earthquake samples are of this type. The second is the AD model,in which the strain release decelerates in broader areas and accelerates in smaller areas around the epicenter with an occupying ratioof approximately 19%. The third is ASR,in which only accelerating strain release can be observed. Cases of this model amount to about 14%. The fourth is DSR,in which only decelerating strain release can be checked,amounting to about 24%. There is only one earthquake sample of the fifth type (LSR),which shows a linear strain release. There is a 3~6 years difference in the duration of pre-shock sequences between the accelerating and decelerating models. This means that seismic quiescence against a background of increased seismicity of small earthquakes before large earthquakes are a typical feature in general. For the DA model,the average size of critical regions for steady accelerating and decelerating strain release is about 260km to 400km and 100km to 200km,respectively,3 to 5 times and 1 to 2 times the rupture size of an earthquake of magnitude 7. 0. The AD model is the opposite of the DA model. The model parameter,m value,has good stability. The ratio of ASR is about the same for accelerating seismic strain release phenomena,no matter what the strain release models are,or how large the strain release quantity is. With regard to decelerating seismic strain release phenomena, the DA model has the most distinctive decelerating strain release characteristic and is the typical feature of seismic strain release,i. e. "decelerating in-accelerating out seismic strain model". 展开更多
关键词 Accelerating strain release Decelerating strain release Size of critical region Duration of pre-shock sequence
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Effects of Direct Drilling on Soil Trafficability: Exploratory Results
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作者 Mokhtar Bouchendira Khelifa M'Hedhbi Belgacem Medyouni 《Journal of Earth Science and Engineering》 2012年第4期205-208,共4页
When applying conservation agriculture based on DD (direct drilling), soil is rarely disturbed by machinery, but is often subject to vehicle pressure that is frequent and intense. Soil compaction could be deeply mod... When applying conservation agriculture based on DD (direct drilling), soil is rarely disturbed by machinery, but is often subject to vehicle pressure that is frequent and intense. Soil compaction could be deeply modified, and DD can improve soil sustainability during rainy seasons. The technique of cone penetration resistance is still the easiest and most direct way to charaeterise soil compaction distribution of soils. Then measurements of cone penetration resistance were conducted on two typical agricultural soil zones in Tunisia. At the experimental site, soils were submitted to DD during different durations in the context of the conservative agriculture in order to investigate the evolution of compaction measured by a cone penetrometer during different time periods and to describe the trafficability of the tested soils. The results showed that (1) soil compaction increased with time application (years) of DD; (2) soil compaction was affected by soil depth and (3) DD improved the uniformity of soil compaction distribution within soil profile. Consequently, DD seems to improve trafficability of agriculture soils, which makes an easy access to a field during rainy times. 展开更多
关键词 COMPACTION no till agriculture conservation soil penetration cone index portability.
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