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Distribution law and susceptibility of geohazards across a gradient belt of the Western Sichuan Plateau
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作者 LI Tianbin WANG Jianfeng +4 位作者 HE Chaoyang MENG Lubo LI Chaofei MA Junjie WEI Daqiang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1849-1867,共19页
Across a gradient belt of the Western Sichuan Plateau,geohazards have seriously limited economic and social development.According to incomplete statistics,15,673 geohazards have been recorded in the study area.In orde... Across a gradient belt of the Western Sichuan Plateau,geohazards have seriously limited economic and social development.According to incomplete statistics,15,673 geohazards have been recorded in the study area.In order to mitigate the threat of geohazards to human engineering activities in the region,an overall understanding of the distribution pattern of geohazards and susceptibility assessment are necessary.In this paper,a gradient belt of the Western Sichuan Plateau and its zoning criteria were defined.Subsequently,on the basis of relief amplitude,distance to faults,rainfall,and human activities,three indicators of endogenic process were introduced:Bouguer gravity anomaly gradient,vertical deformation gradient,and horizontal deformation gradient.Thereafter,the distribution patterns of geohazards were investigated through mathematical statistics and ArcGIS software.By randomly selecting 10,449 hazards,a geohazard susceptibility map was generated using the Information Value(IV)model.Finally,the IV model was validated against 5224 hazards using the Area Under Curve(AUC)method.The results show that 47.6%of the geohazards were distributed in the zone of steep slope.Geohazards showed strong responses to distance to faults,human activities,and annual rainfall.The distribution of geohazards in the gradient belt of the Western Sichuan Plateau is more sensitive to vertical internal dynamics factors(such as vertical deformation gradient and Bouguer gravity anomaly gradient)without any apparent sensitivity to horizontal internal dynamics factors.The areas of high and very-high risk account for up to 32.22%,mainly distributed in the Longmenshan and Anning River faults.According to the AUC plot,the success rate of the IV model for generating the susceptibility map is 76%.This susceptibility map and geohazard distribution pattern can provide a reference for geological disaster monitoring,preparation of post-disaster emergency measures,and town planning. 展开更多
关键词 Gradient belt GEOHAZARDS Distribution law Bouguer Gravity anomaly gradient Vertical deformation gradient SUSCEPTIBILITY
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Fracture propagation law of temporary plugging and diversion fracturing in shale reservoirs under completion experiments of horizontal well with multi-cluster sand jetting perforation
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作者 ZOU Yushi LI Yanchao +3 位作者 YANG Can ZHANG Shicheng MA Xinfang ZOU Longqing 《Petroleum Exploration and Development》 SCIE 2024年第3期715-726,共12页
This study conducted temporary plugging and diversion fracturing(TPDF)experiments using a true triaxial fracturing simulation system within a laboratory setting that replicated a lab-based horizontal well completion w... This study conducted temporary plugging and diversion fracturing(TPDF)experiments using a true triaxial fracturing simulation system within a laboratory setting that replicated a lab-based horizontal well completion with multi-cluster sand jetting perforation.The effects of temporary plugging agent(TPA)particle size,TPA concentration,single-cluster perforation number and cluster number on plugging pressure,multi-fracture diversion pattern and distribution of TPAs were investigated.A combination of TPAs with small particle sizes within the fracture and large particle sizes within the segment is conducive to increasing the plugging pressure and promoting the diversion of multi-fractures.The addition of fibers can quickly achieve ultra-high pressure,but it may lead to longitudinal fractures extending along the wellbore.The temporary plugging peak pressure increases with an increase in the concentration of the TPA,reaching a peak at a certain concentration,and further increases do not significantly improve the temporary plugging peak pressure.The breaking pressure and temporary plugging peak pressure show a decreasing trend with an increase in single-cluster perforation number.A lower number of single-cluster perforations is beneficial for increasing the breaking pressure and temporary plugging peak pressure,and it has a more significant control on the propagation of multi-cluster fractures.A lower number of clusters is not conducive to increasing the total number and complexity of artificial fractures,while a higher number of clusters makes it difficult to achieve effective plugging.The TPAs within the fracture is mainly concentrated in the complex fracture areas,especially at the intersections of fractures.Meanwhile,the TPAs within the segment are primarily distributed near the perforation cluster apertures which initiated complex fractures. 展开更多
关键词 shale temporary plugging and diversion fracturing multi-cluster sand jetting perforation distribution of temporary plugging agent fracture propagation law
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ANALYTIC AND TOPOLOGICAL CHARACTERIZATIONS OF COMPLETELY DISTRIBUTIVE LAW 被引量:1
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作者 刘应明 罗懋康 彭谦 《Chinese Science Bulletin》 SCIE EI CAS 1990年第15期1237-1240,共4页
Using an algebraic property, the completely distributive law, we have ever given out a characterization of the semicontinuity of lattice-valued mappings. How about the inverse implication? That is to say, can we analy... Using an algebraic property, the completely distributive law, we have ever given out a characterization of the semicontinuity of lattice-valued mappings. How about the inverse implication? That is to say, can we analytically characterize the completely distributive law? Moreover, can we characterize the completely distributive law in terms of fuzzy topology? The purpose of this note is to answer affirmatively these questions for the infinitely distributive lattices. This study connecting algebra with analysis and topology seems to be rather interesting. 展开更多
关键词 COMPLETELY distributive law semicontinuous lattice-valued mappings induced topology.
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Power Law网络中一种资源定位机制的设计与仿真 被引量:2
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作者 李静 《系统仿真学报》 CAS CSCD 北大核心 2009年第3期735-738,共4页
如何有效地进行资源定位是影响广域网内分布式系统性能的重要因素,已有的一些资源查找算法引入了小世界原理来提高定位效率和降低网络负载,但没有较好解决小世界网络的构造问题。在Kleinberg小世界模型的基础上,利用幂率网络特性,提出... 如何有效地进行资源定位是影响广域网内分布式系统性能的重要因素,已有的一些资源查找算法引入了小世界原理来提高定位效率和降低网络负载,但没有较好解决小世界网络的构造问题。在Kleinberg小世界模型的基础上,利用幂率网络特性,提出了一个小世界网络的构造方法PLSWCP(Power Law oriented Small World Construction Protocol),并给出了该方法的数学分析和实现。该方法是分布式的,不必拥有全局知识,每个节点只需维护局部视图,即可使资源定位具有小世界特征所带来的优化的时间复杂度。分析和实验结果表明,该方法可以提高资源定位的效率,具有良好的扩展性,自适应性和负载均衡性。 展开更多
关键词 广域网 幂率 小世界 分布式
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CONCEPT, DISTRIBUTION LAW AND FORMATION MACHANISM OF INLAND SALINE ALKALINE WETLAND─ ─ Taking Songliao Plain for Example 被引量:5
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作者 SUN Guang you1, LUO Xin zheng2 , YI Fu ke1 , ZHANG Xiao ping1 (1.Changchun Institute of Geography, the Chinese Academy of Sciences,Changchun 130021,P.R.China 2.Institute of Geography, Academy of Henan Province, Zhengzhou 450052,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2000年第3期63-69,共2页
The paper, taking Songliao Plain for example, studied the concept, distribution law and formation mechanism of inland saline alkaline wetland. The inland saline alkaline wetland is distributed over the inland region o... The paper, taking Songliao Plain for example, studied the concept, distribution law and formation mechanism of inland saline alkaline wetland. The inland saline alkaline wetland is distributed over the inland region of arid or semi arid climate; it is the wet or slightly stagnant environment, forming saline alkaline soil and salt vegetation and making the geogra phical environment fonming complex with an ecosystem of saline alkaline wetland. The laws of zone nature and non zone nature control the distribution of the inland saline alkaline wetland that extensively spreads in north part of China and other countries. The inland saline alkaline wetland is formed jointly by atmosphere, hydrosphere, lithosphere and biosphere including intellectual sphere. Under the special condition, the artificial activity is possibly the key function. In order to improve the human environment, it is a great duty confronting the whole world to rationally transform the inland saline alkaline wetland. Therefore, we presented an anti inland theory to promote the environment transformation. 展开更多
关键词 Songliao Plain INLAND SALINE ALKALINE WETLAND WETLAND distribution law WETLAND CONCEPT WETLAND FORMATION mechanism
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A Research of the Finding and Distribution Law of Taisui in Modern China 被引量:11
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作者 Chao-Jiang Wang Shi-Qing Wang 《Agricultural Sciences》 2015年第4期407-414,共8页
The academic world is still uncertain about the classification of Taisui. It is debating whether Taisui is living or not, myxomycete complex or fungi. The passage studies the 228 finding reports of Taisui in modern Ch... The academic world is still uncertain about the classification of Taisui. It is debating whether Taisui is living or not, myxomycete complex or fungi. The passage studies the 228 finding reports of Taisui in modern China. It confirms that the first finding time of Taisui in modern China is 1963, and the first reported time is 1992. Taisui has been found in 25 administrative divisions. Taisui occurs the most times in Shandong Province. Besides, provinces where Taisui has been found most times are in northern China. Finding locations of Taisui vary from place to place. Taisui is most often found in normal earth layer, with different burying depth. Taisui is mainly found through seeing, tramping, and digging. Taisui findings lack subjective motivations and are connected with the life and production of the finders. Conclusion: Taisui is an object growing in earth layer. 展开更多
关键词 Taisui Finding law DISTRIBUTION law China in MODERN TIMES
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Plastic zone distribution laws and its types of surrounding rock in large-span roadway 被引量:14
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作者 Li Chong Xu Jinhai +1 位作者 PanJianzhong Ma Chao 《International Journal of Mining Science and Technology》 2012年第1期23-28,共6页
In order to study the distribution laws and types of plastic zone of surrounding rock in large-span roadway, we analyzed the distribution laws with different spans and lateral pressures using FLAC3D numerical calcu- l... In order to study the distribution laws and types of plastic zone of surrounding rock in large-span roadway, we analyzed the distribution laws with different spans and lateral pressures using FLAC3D numerical calcu- lation software. Based on the roadway support difficulty and distribution laws of the plastic zone of sur- rounding rock, we defined the large-span roadway and classified the types of large-span rectangular roadways. As a result, the distribution laws of the plastic zone on surrounding rock in a rectangular roadway with different spans and lateral pressures were obtained. The results show that the area of the plastic zone on surrounding rock increased with the increase of the spans and lateral pressures, and the plastic zone was symmetrical to the center line of roadway. At λ=0.5, 1.0, 1.5, and 2.0, the plastic zone presented "addle- shape" distribution, "ellipse" distribution, "thin and high" distribution and "inverse trapezium" distribu- tion, respectively. In addition, we classified the roadways into four types according to the different lateral pressures and spans, including small-span, moderate-span, large-span and extreme-large-span roadways. 展开更多
关键词 Large-span roadway Plastic zone Distribution law TYPE
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Seepage field distribution and water inflow laws of tunnels in water-rich regions 被引量:6
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作者 LI Zheng CHEN Zi-quan +2 位作者 HE Chuan MA Chun-chi DUAN Chao-ran 《Journal of Mountain Science》 SCIE CSCD 2022年第2期591-605,共15页
Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the str... Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the structural safety of tunnels in water-rich regions.In this paper,a tunnel seepage model testing system was used to conduct experiments of the grouting circle and primary support with different permeability coefficients.The influences of the supporting structures on the water inflow laws and the distribution of the water pressure in the tunnel were analyzed.With the decrease in the permeability coefficient of the grouting circle or the primary support,the inflow rate of water into the tunnel showed a non-linear decreasing trend.In comparison,the water inflow reduction effect of grouting circle was much better than that of primary support.With the increase of the permeability coefficient of the grouting ring,the water pressure behind the primary lining increases gradually,while the water pressure behind the grouting ring decreases.Thus,the grouting of surrounding rock during the construction of water-rich tunnel can effectively weaken the hydraulic connection,reduce the influence range of seepage,and significantly reduce the decline of groundwater.Meanwhile,the seepage tests at different hydrostatic heads and hydrodynamic heads during tunnel operation period were also conducted.As the hydrostatic head decreased,the water pressure at each characteristic point decreased approximately linearly,and the water inflow rate also had a gradual downward trend.Under the action of hydrodynamic head,the water pressure had an obvious lagging effect,which was not conducive to the stability of the supporting structures,and it could be mitigated by actively regulating the drainage rate.Compared with the hydrostatic head,the hydrodynamic head could change the real-time rate of water inflow to the tunnel and broke the dynamic balance between the water pressure and water inflow rate,thereby affecting the stress state on the supporting structures. 展开更多
关键词 Water-rich tunnel Seepage field distribution Water inflow law Construction period Operation period
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Three-dimensional impact angle constrained distributed cooperative guidance law for anti-ship missiles 被引量:7
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作者 LI Wei WEN Qiuqiu +1 位作者 HE Lei XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期447-459,共13页
This paper investigates the problem of distributed cooperative guidance law design for multiple anti-ship missiles in the three-dimensional(3-D)space hitting simultaneously the same target with considering the desired... This paper investigates the problem of distributed cooperative guidance law design for multiple anti-ship missiles in the three-dimensional(3-D)space hitting simultaneously the same target with considering the desired terminal impact angle constraint.To address this issue,the problem formulation including 3-D nonlinear mathematical model description,and communication topology are built firstly.Then the consensus variable is constructed using the available information and can reach consensus under the proposed acceleration command along the line-of-sight(LOS)which satisfies the impact time constraint.However,the normal accelerations are designed to guarantee the convergence of the LOS angular rate.Furthermore,consider the terminal impact angle constraints,a nonsingular terminal sliding mode(NTSM)control is introduced,and a finite time convergent control law of normal acceleration is proposed.The convergence of the proposed guidance law is proved by using the second Lyapunov stability method,and numerical simulations are also conducted to verify its effectiveness.The results indicate that the proposed cooperative guidance law can regulate the impact time error and impact angle error in finite time if the connecting time of the communication topology is longer than the required convergent time. 展开更多
关键词 distributed cooperative guidance law impact angle constraint communication topology nonsingular terminal sliding mode(NTSM)control finite time convergent
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Energy and first law of thermodynamics for Born-Infeld-anti-de-Sitter black hole 被引量:1
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作者 魏益焕 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期212-216,共5页
We calculate the local energy and the energy density of the Reisner-Norstrom-anti-de-Sitter black hole, study the first law of thermodynamics and show the Smarr formula for the Born-Infeld-anti-de-Sitter black hole. A... We calculate the local energy and the energy density of the Reisner-Norstrom-anti-de-Sitter black hole, study the first law of thermodynamics and show the Smarr formula for the Born-Infeld-anti-de-Sitter black hole. Applying the first law of thermodynamics to the black hole region, we analyse the three energy exchange processes between the black hole region and the outer and the inner regions. 展开更多
关键词 first law of thermodynamics energy distribution energy exchange
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Applicability of law of mass action to distribution of manganese between slag melts and liquid iron 被引量:1
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作者 张鉴 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期778-783,共6页
According to the law of mass action and the coexistence theory of slag structure, the distribution of manganese between MnO FeO SiO 2 and MgO MnO FeO SiO 2 slag melts as well as liquid iron was analyzed. It is shown t... According to the law of mass action and the coexistence theory of slag structure, the distribution of manganese between MnO FeO SiO 2 and MgO MnO FeO SiO 2 slag melts as well as liquid iron was analyzed. It is shown that K ′ Mn and K MnO are only dependent on temperature and don’t change with basicities and compositions of slag melts. So the distribution of manganese between the above mentioned slag melts and molten iron obeys the law of mass action. But analysis of experimental results from other sources shows that K ′ Mn and K MnO really change with basicities of slag, which is probably arisen from not approaching equilibrium under low basicity slag melts. 展开更多
关键词 manganese distribution the law of mass action the coexistence theory of slag structure mass action concentration
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Leak Detection in Water Distribution Systems Using Bayesian Theory and Fisher’s Law 被引量:1
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作者 张宏伟 王丽娟 《Transactions of Tianjin University》 EI CAS 2011年第3期181-186,共6页
A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of para... A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of parameter values was quantified by probability density function and updated by Bayesian theory. Values of the parameters were estimated based on Fisher’s law. The amount of leaks was estimated by back propagation neural network. Based on flow characteristics in water distribution systems, the location of leaks can be estimated. The effectiveness of the proposed method was illustrated by simulated leak data of node pressure head and flow rate of pipelines in a test pipe network, and the leaks were spotted accurately and renovated on time. 展开更多
关键词 water distribution systems LEAK DETECTION EPANET Fisher's law Bayesian theory back propagationneural network
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Power-law Distribution of Normal Fault Displacement and Length and Estimation of Extensional Strain due to Normal Faults:A Case Study of the Sierra de San Miguelito, Mexico 被引量:1
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作者 XUShunshan A.F.NIETO-SAMANIEGO S.A.ALANIZ-ALVAREZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第1期36-42,共7页
The Sierra de San Miguelito is a relatively uplifted area and is constituted by a large amount of silicic volcanic rocks with ages from middle to late Cenozoic. The normal faults of the Sierra de San Miguelito are Dom... The Sierra de San Miguelito is a relatively uplifted area and is constituted by a large amount of silicic volcanic rocks with ages from middle to late Cenozoic. The normal faults of the Sierra de San Miguelito are Domino-style and nearly parallel. The cumulative length and displacement of the faults obey power-law distribution. The fractal dimension of the fault traces is -1.49. Using the multi-line one-dimensional sampling, the calculated exponent of cumulative fault displacements is -0.66. A cumulative curve combining measurements of all four sections yielded a slope of -0.63. The displacement-length plot shows a non-linear relationship and large dispersion of data. The large dispersion in the plot is mainly due to the fault linkage during faulting. An estimation of extensional strain due to the normal faults is ca. 0.1830. The bed extension strain is always less than or equal to the horizontal extension strain. The deformation in the Sierra de San Miguelito occurred near the surface, producing pervasive faults and many faults are too small to appear in maps and sections at common scales. The stretching produced by small faults reach ca. 33% of the total horizontal elongation. 展开更多
关键词 power-law distribution normal faults small faults finite strain Mexico
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Revisiting the Curie-Von Schweidler Law for Dielectric Relaxation and Derivation of Distribution Function for Relaxation Rates as Zipf’s Power Law and Manifestation of Fractional Differential Equation for Capacitor 被引量:1
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作者 Shantanu Das 《Journal of Modern Physics》 2017年第12期1988-2012,共25页
The classical power law relaxation, i.e. relaxation of current with inverse of power of time for a step-voltage excitation to dielectric—as popularly known as Curie-von Schweidler law is empirically derived and is ob... The classical power law relaxation, i.e. relaxation of current with inverse of power of time for a step-voltage excitation to dielectric—as popularly known as Curie-von Schweidler law is empirically derived and is observed in several relaxation experiments on various dielectrics studies since late 19th Century. This relaxation law is also regarded as “universal-law” for dielectric relaxations;and is also termed as power law. This empirical Curie-von Schewidler relaxation law is then used to derive fractional differential equations describing constituent expression for capacitor. In this paper, we give simple mathematical treatment to derive the distribution of relaxation rates of this Curie-von Schweidler law, and show that the relaxation rate follows Zipf’s power law distribution. We also show the method developed here give Zipfian power law distribution for relaxing time constants. Then we will show however mathematically correct this may be, but physical interpretation from the obtained time constants distribution are contradictory to the Zipfian rate relaxation distribution. In this paper, we develop possible explanation that as to why Zipfian distribution of relaxation rates appears for Curie-von Schweidler Law, and relate this law to time variant rate of relaxation. In this paper, we derive appearance of fractional derivative while using Zipfian power law distribution that gives notion of scale dependent relaxation rate function for Curie-von Schweidler relaxation phenomena. This paper gives analytical approach to get insight of a non-Debye relaxation and gives a new treatment to especially much used empirical Curie-von Schweidler (universal) relaxation law. 展开更多
关键词 Power law RELAXATION RATE Distribution FRACTIONAL Derivative FRACTIONAL Integration Curie-Von Schweidler law Time-Constants Laplace INTEGRAL Zipf’s law INTEGRAL Representation Time Dependent RELAXATION RATE Scale Dependent RELAXATION RATE Non-Debye RELAXATION
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An optimized framework for degree distribution in LT codes based on power law
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作者 Asim Muhammad Choi GoangSeog 《Journal of Central South University》 SCIE EI CAS 2013年第10期2693-2699,共7页
LT codes are practical realization of digital fountain codes, which provides the concept of rateless coding. In this scheme, encoded symbols are generated infinitely from k information symbols. Decoder uses only(1+α)... LT codes are practical realization of digital fountain codes, which provides the concept of rateless coding. In this scheme, encoded symbols are generated infinitely from k information symbols. Decoder uses only(1+α)k number of encoded symbols to recover the original information. The degree distribution function in the LT codes helps to generate a random graph also referred as tanner graph. The artifact of tanner graph is responsible for computational complexity and overhead in the LT codes. Intuitively, a well designed degree distribution can be used for an efficient implementation of LT codes. The degree distribution function is studied as a function of power law, and LT codes are classified into two different categories: SFLT and RLT codes. Also, two different degree distributions are proposed and analyzed for SFLT codes which guarantee optimal performance in terms of computational complexity and overhead. 展开更多
关键词 FOUNTAIN CODES DEGREE distribution OVERHEAD computational COMPLEXITY power law
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Power Law Distributions in the Experiment for Adjustment of the Ion Source of the NBI System
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作者 韩筱璞 胡纯栋 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第6期3102-3104,共3页
The experiential adjustment process in an experiment on the ion source of the neutral beam injector system for the HT-7 Tokamak is reported in this paper. With regard to the data obtained in the same condition, in arr... The experiential adjustment process in an experiment on the ion source of the neutral beam injector system for the HT-7 Tokamak is reported in this paper. With regard to the data obtained in the same condition, in arranging the arc current intensities of every shot with a decay rank, the distributions of the arc current intensity correspond to the power laws, and the distribution obtained in the condition with the cryo-pump corresponds to the double Pareto distribution. Using the similar study method, the distributions of the arc duration are close to the power laws too. These power law distributions are formed rather naturally instead of being the results of purposeful seeking. 展开更多
关键词 power law distribution adjustment experiment ion source double Pareto distribution
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Effects of PHC on Water Quality of Jiaozhou Bay Ⅵ.Transfer Laws
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作者 Yang Dongfang Wang Fengyou +2 位作者 Zhu Sixi Long Mingzhong Yang Xiuqin 《Meteorological and Environmental Research》 CAS 2016年第5期69-72,共4页
According to the investigation data of PHC content in Jiaozhou Bay,China from 1979 to 1983,the content,sources,horizontal,vertical and seasonal distribution,and transfer laws of PHC in the water of the bay were analyz... According to the investigation data of PHC content in Jiaozhou Bay,China from 1979 to 1983,the content,sources,horizontal,vertical and seasonal distribution,and transfer laws of PHC in the water of the bay were analyzed on spatial scale,and the processes of pollution sources,land transfer,sedimentation,and water transfer of PHC in Jiaozhou Bay were discussed on temporal scale. These laws and changing processes could provide theoretical foundation for studies on water transfer of PHC and other heavy metals. 展开更多
关键词 PHC Distribution Changes TRANSFER lawS Jiaozhou BAY China
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Study on the Size Distribution and Similarity Law of Bubble Nuclei in Water
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作者 YAO Xiong-liang LI Zhi-peng +1 位作者 SUN Long-quan CHEN Wei-chu 《China Ocean Engineering》 SCIE EI CSCD 2021年第3期432-442,共11页
To study the distribution characteristics and similarity laws of nuclei under different pressures,based on the selfdesigned decompression chamber and the acoustic measuring system,the size distributions of nuclei in t... To study the distribution characteristics and similarity laws of nuclei under different pressures,based on the selfdesigned decompression chamber and the acoustic measuring system,the size distributions of nuclei in the degassed tap water under negative ambient pressures were measured.A number density distribution function of nuclei based on the modified Weibull distribution function was proposed and verified by the experimental measurement results and some published data of nuclei size distribution.Based on this nuclei number density distribution function,the similarity law of the nuclei size distribution was analyzed:in the scale experiment,the value of exponential in the similarity law of the nuclei number density should be determined by the nuclei size distribution of the water in the prototype experiment and the actual nuclei size distribution of the water in the model experiment.And a precondition is that the nuclei size distributions are similar. 展开更多
关键词 nuclei number density distribution function MICROBUBBLE ambient pressure similarity law
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THERMAL PROPERTIES AND TEMPERATURE DISTRIBUTION OF SNOW/FIRN ON THE LAW DOWE ICE CAP, ANTARCTICA
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作者 Ren Jiawen, Qin Dahe and Huang Maohuan Lanzhou Institute of Glaciology and Geocryology, Chinese Academy of Sciences, Lanzhou, 730000, China 《Chinese Journal of Polar Science》 1991年第2期38-46,共9页
Based on detailed measurements of density and a numerous data on temperature in shallow boreholes (about 20m deep), the thermal properties and temperature distribution of snow / firn layer on the Law Dome ice cap, Ant... Based on detailed measurements of density and a numerous data on temperature in shallow boreholes (about 20m deep), the thermal properties and temperature distribution of snow / firn layer on the Law Dome ice cap, Antarctica, are discussed. According to a review of works on thermal properties of snow by Yen (1981), a relationship between thermal conductivity (K) and density (ρ) is proposed to be expressed by a formula, K=0.0784+2.697/ρ2. Then an eqation of heat transfer in a deformed ununiform medium is applied and solved analytically by two approaches. Comparison of calculated and measured temperatures indicates that the difference is mainly dependent on the determination of boundary donditions. 展开更多
关键词 law Dome Ice Cap snow-firn layer thermal properties temperature distribution.
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LAWS GOVERNING THE DISTRIBUTION OF LEAD-ZINC DEPOSITS IN CHINA
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作者 YIN Hanhui(Changsha Institute of Geotectonics, Academia Sinica, Changsha, 410013, China ) 《Geotectonica et Metallogenia》 1997年第Z2期78-88,共11页
An attempt is made in this paper to describe the following laws governing the distribution of lead-zinc deposits in China: spatial distribution laws, temporal distribution laws, deep level control laws, and deposits a... An attempt is made in this paper to describe the following laws governing the distribution of lead-zinc deposits in China: spatial distribution laws, temporal distribution laws, deep level control laws, and deposits association and zoning laws. 展开更多
关键词 Lead-zinc DEPOSITS spatial-temporal DISTRIBUTION DEEP level control lawS DEPOSITS ASSOCIATION and ZONING lawS
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