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Search Results: 1 - 10 of 120099 matches for " Ruihe Wang "
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Chaotic Vibration Analysis of the Bottom Rotating Drill String
Qilong Xue,Ruihe Wang,Feng Sun,Zhiyuan Huang
Shock and Vibration , 2014, DOI: 10.1155/2014/429164
Abstract: Drill string vibration is a widely studied topic. This paper developed a real-time measurement system near the drilling bit and extracted the lateral vibration, longitudinal vibration time series of bottom rotating drill string. In order to reconstruct the phase space, we estimated the delay time with mutual information and calculated the embedding dimension through Cao’s method. Finally, the chaotic characterization of the system is analyzed by calculating the correlation dimension and the largest Lyapunov exponent. The results show that such system can exhibit positive finite-time Lyapunov exponents and a clear convergence toward the correlation dimension, which is a strong indicator for the chaotic behavior of the system. It is expected that the new dynamics found in this paper could be of potential implication to the control methods of the drill string vibration. 1. Introduction In oil and gas drilling engineering, the well is created by drilling a hole 5 to 50 inches (127.0?mm to 914.4?mm) in diameter into the earth with a drilling rig that rotates a drill string with a bit attached. In the process, severe drill string vibration is a major contributor to downhole tool failure. It may also cause hole damage and increase the need for more frequent rig repair. Typically, the drilling string vibration can be divided into three types or modes: lateral, longitudinal, and torsional. The destructive nature of each type of vibration is different. Lateral and longitudinal vibrations of the drill string have been undertaken extensive research since it proposed from mid-1960s, The main reason that caused the fatigue failure of the bottomhole assembly (BHA) [2] was considered to be the vibration of the drill string. Many studies of the drill string focused on the determination of natural frequencies [3, 4], bending stress calculation [5, 6], stability analysis [7], lateral displacement prediction [8], and so forth. Spanos et al. [9] established the finite element model of drill string lateral vibration and analyzed nonlinear random vibration. Chunjie and Tie [10] obtained the natural frequency of drill string longitudinal vibration from a finite element model. Vibrations of all three types (lateral, longitudinal, and torsional) may occur during rotary drilling and are coupled. Single vibration model cannot well describe the dynamics of BHA; furthermore, to establish a precise bottom hole kinetic theory model is difficult to achieve because of the underground complex situation. Additionally, the process of drill bit break rocks is a nonlinear process which is
A Study of Inverse Problems Based on Two Kinds of Special Matrix Equations in Euclidean Space
Rui Huang,Xiaodong Wu,Ruihe Wang,Hui Li
Algebra , 2014, DOI: 10.1155/2014/392467
Abstract: Two special classes of symmetric coefficient matrices were defined based on characteristics matrix; meanwhile, the expressions of the solution to inverse problems are given and the conditions for the solvability of these problems are studied relying on researching. Finally, the optimal approximation solution of these problems is provided. 1. Introduction In recent years, a lot of matrix problems have been used widely in the fields of structural design, automatic control, physical, electrical, nonlinear programming and numerical calculation, for example, a matrix Eigen value problem was applied for mixed convection stability analysis in the Darcy media by Serebriiskii et al. [1] and some of the problems based on the nonskew symmetric orthogonal matrices were studied by Hamed and Bennacer in 2008 [2], but some of the matrix inverse problems still need further research in order to make it easier to discuss relevant issues. Therefore, in this paper, we studied the inverse problems of two kinds of special matrix equations based on the existing research achievements, moreover, the expressions and conditions of the matrix solutions are given by related matrix-calculation methods. Some definitions and assumptions of the inverse problem for two forms of special matrices are given in Section 2. In Sections 3 and 5 we discuss the existence and expressions of general solution based on the two classes of matrices, and in Sections 4 and 6 we prove the uniqueness of matrices for researching related inverse problems. 2. Definitions and Assumptions of Inverse Problems for Two Forms of Special Matrices In order to research some inverse problems of related matrices, we give the following definitions and assumptions. Definition 1. When , , , , , and , will be called the first-class special symmetric matrix and the set of these special symmetric matrices is denoted by . The corresponding problems are as follows. Problem 1. When , can be obtained, so that . Problem 2. When , can be obtained, so that , where is the solution set of the first problem. Definition 2. When , and , will be called the second-class special symmetric matrix and the set of these special symmetric matrices is denoted by . The corresponding problems are as follows. Problem 1. When , can be found, so that . Problem 2. When , can be found, so that , where is the solution set of the first problem. 3. Existence and Expression of General Solutions Based on the First-Class Special Symmetric Matrix for Problem 1 To research the structure and properties of the special symmetric matrix , first of all, we have the
STUDY ON ROCK DRILLING BY SWIRLING JET
旋转射流破岩成孔规律研究

Bu Yuhuan,Wang Ruihe,Zhou Weidong,
步玉环
,王瑞和,周卫东

岩石力学与工程学报 , 2003,
Abstract: Based on the previous research on structural and flow characteristics of swirling jet. the testing study is made to analyse the factors affecting rock breaking efficiency of swirling jet, such as pump pressure, jet distance, rock permeability and intensity, consistency of additive, etc. Meanwhile the distinction of the effects of rock permeability on swirling jet and straight jet is studied. The results show that rock breaking efficiency by swirling jet apparently increases with the decrease of rock strength and the increase of rock permeability at the same standoff distance and pump pressure. The rock permeability plays important role in the rock breaking effect of jet. The effect of rock permeability on the swirling jet is greater than that on the straight jet. Meanwhile the results show that the depth, diameter and volume of the hole drilled by swirling jet apparently increase at the beginning and decrease afterwards with the increase of consistency of additive. The most excellent consistency of additive is 200~300 mmp in this experiment.
NUMERICAL SIMULATION ON ROCK BREAKING UNDER HIGH PRESSURE WATER JET
高压水射流破岩的数值模拟分析

JET Ni Hongjian,Wang Ruihe,Ge Hongkui,
倪红坚
,王瑞和 葛洪魁

岩石力学与工程学报 , 2004,
Abstract: The evolvement of rock damage impacted by high pressure water jet is simulated with nonlinear FEM and dynamic rock damage model. The numerical results show that most of rock damage and breakage take place in several milliseconds,the main damage behavior under a general continual jet is tensile damage caused by the rock unload and the jet impacting,and the evolvement of rock damage shows step changed. The effect of water jet parameters on rock breaking is studied. The numerical results agree well with experimental results,so that the method established in this paper can simulate rock breaking under high pressure water jet and the study results can be used to design and optimize rock breaking under water jet.
Children''''s Cognitive Development of Emotional Display Rules
儿童对情绪表达规则的认知发展

Hou Ruihe,Yu Guoliang,Lin Chongde,
侯瑞鹤
,俞国良,林崇德

心理科学进展 , 2004,
Abstract: Childrens cognitive construction of emotional display rules(EDRs) was an important task during their socialization and the development of emotion. This review synthesized many researches involving in the concept and cognitive development theory and measurement of EDRs, and reflecting the relation between EDRs cognitive development and other factors. The results mainly demonstrated three relationships. First, childrens cognitive development of EDRs was most strongly related to age and gender. Second, positive family emotion environment was related to childrens more knowledge and use of EDRs and lower negative affect. Third, childrens knowledge and use of EDRs was positively associated with their social competence.
Cognitive Characteristics of Emotional Display Rule Among Children with Learning Disabilities
学习不良儿童对情绪表达规则的认知特点

Yu Guoliang,Hou Ruihe,Luo Xiaolu,
俞国良
,侯瑞鹤,罗晓路

心理学报 , 2006,
Abstract: Emotional display rule cognitive tasks and emotion decision figures were employed in the present experiment.90 children selected from 1~(st),3~(rd) and 5~(th) grade in a primary school(44 learning disabilities and 46 normal) were interviewed individually with 6 stories.The results indicated that expression regulation knowledge of learning disabilities and normal children increased as their grade increased,but the developmental level was different between two groups.There were no significant gender differences,and group and grade interaction was not found.Moreover,learning disabilities children report less social-orient goals than normal children,and there were no significant differences in self-protective goals.Comparing the combination of emotion display rule use and goals in the two samples,suggested that learning disabilities children lack of the ability to integrate different emotion knowledge,in addition,normal children displayed more cognitive flexibility according to different interpersonal relationship than learning disabilities.
Emotion Regulation Theory: A Mental Health Perspective
情绪调节理论:心理健康角度的考察

Hou Ruihe,Yu Guoliang,
侯瑞鹤
,俞国良

心理科学进展 , 2006,
Abstract: 以情绪调节与心理健康的关系为切入口,对情绪调节理论进行了阐述:早期精神分析理论,把情绪调节看作被动防御机制,情绪调节困难导致心理问题;情境观把情绪调节看作为应对情绪情境即时的心理反应,策略使用情况与心理健康相关;过程观认为情绪调节在情绪发生过程中展开,不同阶段所采用的调节策略与心理健康相关,后又把调节过程扩展到情绪恢复到正常状态所持续时间,时间与心理健康相关;结构观认为情绪调节结构的差异影响心理健康.
Software Industry Cluster be Disagreement on Theory and Practice  [PDF]
Yang Wang, Luqian Wang
Intelligent Information Management (IIM) , 2010, DOI: 10.4236/iim.2010.210069
Abstract: In the view of traditional industry cluster theory, it is easy to copy the software industry cluster pattern, or it is easy to copy another Silicon Valley, due to low reliability of the resources and the guidance factors of locations in software industry. But it is much more difficult to copy a Silicon Valley mode practically than imaginatively and the difficulties of bringing up and supporting high-tech initiatives is more than theoretic anticipation. In China, the software companies have just gathered together geographically and therefore no initiative center can be formed. All these above signify that software industry cluster is distinct from the traditional industry clusters, but the cognition of the reasons of software industry cluster is not clear yet. Furthermore, reasonable explanations of the bewilderment in the economical practice of software industry cluster are urgently needed.
The Economic Growth Effect of Logistics Industry FDI Analysis  [PDF]
Yang Wang, Luqian Wang
iBusiness (IB) , 2010, DOI: 10.4236/ib.2010.24049
Abstract: Based on the direction of the international FDI changed, from manufacturing to service industries, we should concern about the influence of the introduction of China’s logistics industry FDI to the national economy. The paper sets up regression model to examine logistics FDI and GDP in two aspects of time series and growth rate, we find that the logistics FDI reaches a high correlation with GDP, and logistics FDI is one of the major driving forces of economic development. Therefore, China should expand the introduction of logistics FDI, improve the quality of foreign investment, develop the positive economic growth effect of logistics FDI and promote the change of China’s economic growth pattern to ensure the development of China’s economy.
The Predictive Effects of Online Communication on Well-Being among Chinese Adolescents  [PDF]
Jinliang Wang, Haizhen Wang
Psychology (PSYCH) , 2011, DOI: 10.4236/psych.2011.24056
Abstract: Based on theories and previous studies on online communication, we proposed two hypotheses to better under- stand the effects of online communication on subjective well-being with a sample of Chinese adolescents (n = 190). The results of liner regression analysis found that online communication was positively related to adoles- cents’ subjective well-being. For boys, the coefficient of determination of online communication on subjective well-being was .143, and for girls the coefficient of determination was .040, indicating that boys benefit more from online communication than do girls.
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