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拟阵Q_6与W^4可F-线性表示的构造 被引量:1
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作者 吕国亮 陈斌 《大学数学》 2011年第1期40-44,共5页
对拟阵Q6与W4可F-线性表示的构造进行了研究.用E(G)在R上的链群F0(G,R)表示G的圈拟阵M(G);用松弛拟阵M的极小圈超平面X的方法得到拟阵M′.得到主要结果为:(i)用链群表示了M(K4),M(W4);(ii)用松弛极小圈超平面的方法从M(K4)构造了Q6,从M(... 对拟阵Q6与W4可F-线性表示的构造进行了研究.用E(G)在R上的链群F0(G,R)表示G的圈拟阵M(G);用松弛拟阵M的极小圈超平面X的方法得到拟阵M′.得到主要结果为:(i)用链群表示了M(K4),M(W4);(ii)用松弛极小圈超平面的方法从M(K4)构造了Q6,从M(W4)构造了W4,找出了W4可线性表示的所有域F. 展开更多
关键词 链群 圈拟阵 单扩域 极小圈超平面 松弛 F-可线性表示
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拟阵Q_6与W^4可F-线性表示的构造
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作者 吕国亮 陈斌 《科学技术与工程》 2009年第7期1665-1668,1677,共5页
对拟阵Q6与W4可F-线性表示的构造进行了研究.用E(G)在R上的链群F0(G,R)表示G的圈拟阵M(G);用松弛拟阵M的极小圈超平面X的方法得到拟阵M′。得到主要结果为:(1)用链群表示了M(K4),M(W4);(2)用松弛极小圈超平面的方法从M(K4)构造了Q6,从M(... 对拟阵Q6与W4可F-线性表示的构造进行了研究.用E(G)在R上的链群F0(G,R)表示G的圈拟阵M(G);用松弛拟阵M的极小圈超平面X的方法得到拟阵M′。得到主要结果为:(1)用链群表示了M(K4),M(W4);(2)用松弛极小圈超平面的方法从M(K4)构造了Q6,从M(W4)构造了W4,找出了W4可线性表示的所有域F。 展开更多
关键词 链群 圈拟阵 单扩域 极小圈超平面 松弛 F-可线性表示
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具p:-q共振奇点的Hamiltonian系统的线性化
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作者 许秋瑾 李伟伟 王书讲 《商丘师范学院学报》 CAS 2010年第3期14-17,共4页
研究了二次和三次齐次Hamiltonian系统的1:-2共振奇点的可线性化问题,并利用计算机代数系统求出原点作为鞍点的1:-2型系统可积性与可线性化的必要条件,得出系统可线性化的条件.
关键词 Hamihonian系统:可积性 可线性
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Evaluation Test Research of DR Inspection System for Circumferential Welds in Long Distance Pipeline
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作者 WANG Changjiang WANG Xue +4 位作者 ZHANG Shimin ZHAO Yan LYU Xinyu ZHONG Qian ZHOU Guangyan 《材料导报》 EI CAS CSCD 北大核心 2024年第22期223-229,共7页
Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digit... Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digital radiographic testing and fully evaluate the integrated system inspection ability of equipment,personnel,and processes,a scientific and standardized evaluation method to the system is very necessary.Here investigates the precedents of relevant non-destructive testing evaluation methods at home and abroad,considers the testing characteristics of DR equipment,develops a complete set of DR testing system evaluation procedures.It deeply studies the adaptability methods of program processes from defect production to slicing processing and data statistical calculation for digital radiographic testing evaluation.To check the repeatability and reliability of the detectable system,five process welds with 200 real metallographic defects were fabricated in the laboratory.From the detected results,the DR system has good repeatability in image quality,and the detectable defect size reaches 0.85 mm under achieving 90%detection probability at a confidence level of 95%,the error of detected defect length is±2 mm,and the error of detected defect localization is±5 mm.The qualitative and quantitative detection of defects are accurate and reliable.The test further confirmed the reliable detection ability of the DR detection system,and fully validated the scientific and practical evaluation method designed.The research on the evaluation test method can serve as an important link in the quality control system for the on-site application of digital ray equipment in long-distance pipelines.The designed program,test,and evaluation content can serve as an important basis for the formulation of relevant specifications or standards. 展开更多
关键词 digital ray evaluation test REPEATABILITY RELIABILITY
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双圈拟阵
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作者 吕国亮 陈斌 《大学数学》 北大核心 2007年第4期80-83,共4页
Sim■es Pereira于1992年提出双圈拟阵.本文讨论了(i)双圈拟阵及其秩函数;(ii)次模函数在双圈拟阵中的应用;(iii)双圈拟阵B(G)的横贯拟阵.主要结果:1°由圈矩阵Bf=[I,Bf12]和圈秩的概念,推出M(f0)为双圈拟阵;2°证明了双圈拟阵B... Sim■es Pereira于1992年提出双圈拟阵.本文讨论了(i)双圈拟阵及其秩函数;(ii)次模函数在双圈拟阵中的应用;(iii)双圈拟阵B(G)的横贯拟阵.主要结果:1°由圈矩阵Bf=[I,Bf12]和圈秩的概念,推出M(f0)为双圈拟阵;2°证明了双圈拟阵B(G)等于由子集族{Av∶v∈V(G)},e与v在G中相关联}所确定的横贯拟阵;3°用不同于Matthews(1977)的方法证明了(iii). 展开更多
关键词 双圈拟阵 次模函数 细分 F-可线性表示拟阵 横贯拟阵 关联矩阵
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Precise Calculation System of Total Mix Ration for Lactating Cow 被引量:1
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作者 杨亮 熊本海 +1 位作者 罗清尧 杨琴 《Agricultural Science & Technology》 CAS 2012年第12期2569-2576,共8页
[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and pr... [Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and protein system (CNCPS) with integrating dynamic prediction models on main nutrient requirements of dairy cattle recommended by NRC (2001) and the CNCPS parameter database accumu- lated by Chinese feed database, the ration nutrient requirement dynamic calculation and total mixed ration (TMR) formula optimizing system for Holstein dairy cow was developed using FOXPRO database system and parametric linear programming algo- rithm. [Result] By optimizing a specific cow ration and analyzing its completed nutri- ents, the results showed that this system could entirely consider a lots of nutrient balances, such as concentrate fraction and forage fraction balance, rumen degrad- able protein and rumen undergradable protein balance, crude protein and lactation net energy balance, fibrous substances (ADF, NDF) and non-fiber carbohydrates (NFC) balance, calcium and phosphate balance, electrolytes balance and trace ele- ment balance etc., and could also calculate intestinal amino acid flow in terms of different models. [Conclusion] By using dynamic mathematical equations and comput- erized program, it can be realized for the ration formula design of lactating cow with all-round interoperable but mutual-constraining each other among ration nutrients. 展开更多
关键词 Holstein dairy cattle Total mixed diet Formula model Metabolic protein Linear programming
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Single-Stage Wide-Range CMOS VGA with Temperature Compensation and Linear-in-dB Gain Control 被引量:1
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作者 恽廷华 尹莉 +1 位作者 吴建辉 时龙兴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第4期518-525,共8页
A novel wide-range CMOS variable gain amplifier (VGA) topology is presented. The proposed VGA is composed of a variable transconductor and a novel variable output resistor and can offer a high gain variation range o... A novel wide-range CMOS variable gain amplifier (VGA) topology is presented. The proposed VGA is composed of a variable transconductor and a novel variable output resistor and can offer a high gain variation range of 80dB while using a single variable-gain stage. Temperature-compensation and decibel-linear gain characteristic are achieved by using a control circuit that provides a gain error lower than ±1.5dB over the full temperature and gain ranges. Realized in 0.25μm CMOS technology, a prototype of the proposed VGA provides a total gain range of 64.5dB with 55.6dB-linear range,a P-1dB varying from - 17.5 to 11.5dBm,and a 3dB-bandwith varying from 65 to 860MHz while dissipating 16.5mW from a 2.5V supply voltage. 展开更多
关键词 linear-in-dB temperature compensation variable-gain amplifier automatic gain control
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Transient Characteristics of a Nonlinear GaAs Photoconductive Semiconductor Switch
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作者 王馨梅 施卫 +1 位作者 屈光辉 田立强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1108-1110,共3页
The transient resistance,voltage,and power of a nonlinear GaAs photoconductive semiconductor switch (PCSS) are presented by the finite difference formula to deal with the experiment data, based on the conversation o... The transient resistance,voltage,and power of a nonlinear GaAs photoconductive semiconductor switch (PCSS) are presented by the finite difference formula to deal with the experiment data, based on the conversation of energy in the switch circuit. This method resolves the problem of directly measuring the transient characteristics of PCSS in nonlinear mode. The curve of transient voltage shows that the average electric field of PCSS in the lock-on period is always higher than the Gunn threshold,and increases monotonically. By comparing the transient power curves of the PCSS and the electrical source,it is demonstrated directly that the power shortage leads to the PCSS from the lock-on state into the selfturnoff state,so a controllable turnoff of the PCSS in lock-on by changing the distribution of the circuit power is predicted. 展开更多
关键词 photoconductive semiconductor switch lock-on effect nonlinear mode controllable turnoff
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SOLVABILITY RESULTS OF A CONDITIONAL INPUT-OUTPUT EQUATION BASED ON A TYPE OF NONLINEAR LEONTIEF MODEL
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作者 胡问鸣 刘颖范 沙春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期224-229,共6页
A class of nonlinear and continuous type Leontief model and its corresponding conditional input-output equation are introduced, and two basic problems under the so called positive or negative boundary assumption are p... A class of nonlinear and continuous type Leontief model and its corresponding conditional input-output equation are introduced, and two basic problems under the so called positive or negative boundary assumption are presented. By approaches of nonlinear analysis some solvability results of this equation and continuous perturbation properties of the relative solution sets are obtained, and some economic significance are illustrated by the remark. 展开更多
关键词 conditional Leontief model input-output equation positive (negative) boundary assumption nonlinear analysis SOLVABILITY continuous disturbance
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Necessary and Sufficient Conditions in Smooth Programming with Generalized Convexity 被引量:1
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作者 孙清滢 叶留青 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期33-37,共5页
Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded un... Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded univex functions, a new class of functions that unifies several concepts of generalized convexity. In this paper, additional conditions are attached to the Kuhn Tucker conditions giving a set of conditions which are both necessary and sufficient for optimality in constrained optimization, under appropriate constraint qualifications. 展开更多
关键词 necessary and sufficient conditions generalized convexity nonlinear programming multiobjective programming type functions
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Full-Chip Scalable Routing Framework Considering Congestion and Performance 被引量:1
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作者 姚海龙 蔡懿慈 +1 位作者 洪先龙 周强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1201-1208,共8页
This paper presents a novel full-chip scalable routing framework that simultaneously considers the routing congestion and the circuit performance. In order to bridge the gap, the presented framework calls the detailed... This paper presents a novel full-chip scalable routing framework that simultaneously considers the routing congestion and the circuit performance. In order to bridge the gap, the presented framework calls the detailed router immediately after a global route is extracted. With the interleaving mode of global routing immediately followed by detailed routing, accurate routing resource and congestion information can be obtained, which provides valuable guidance for the following global routing process. The framework features the fast pattern and framed shortest path global router,a maze-based congestion-driven detailed router, and better interaction between the two routers. In the framework, timing critical nets can be assigned higher priority for performance concern, and different net ordering techniques can be adopted for different routing objectives. The framework is tested on a set of commonly used benchmark circuits and compared with a previous multilevel routing framework. Experimental results show that the presented framework obtains significantly better routing solutions than the previous one considering circuit performance, routing completion rate, and runtime. 展开更多
关键词 CONGESTION multilevel routing PERFORMANCE scalable routing
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NON-UNIFORM LINEAR ARRAY CONFIGURATION FOR MIMO RADAR
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作者 彭珍妮 贲德 +1 位作者 张弓 顾海光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期152-156,共5页
Array configuration of multiple-input multiple-output (MIMO) radar with non-uniform linear array (NLA) is proposed. Unlike a standard phased-array radar where NLA is used to generate thinner beam patterns, in MIMO... Array configuration of multiple-input multiple-output (MIMO) radar with non-uniform linear array (NLA) is proposed. Unlike a standard phased-array radar where NLA is used to generate thinner beam patterns, in MIMO radar the property of NLA is exploited to get more distinct virtual array elements so as to improve pa- rameter identifiability, which means the maximum number of targets that can be uniquely identified by the radar. A class of NLA called minimum redundancy linear array (MRLA) is employed and a new method to construct large MRLAs is descrihed. The numerical results verify that compared to uniform linear array (ULA) MIMO radars, NLA MIMO radars can retain the same parameter identifiability with fewer physical antennas and achieve larger aperture length and lower Cramer-Rao bound with the same number of the physical antennas. 展开更多
关键词 MIMO radar parameter identifiability non-uniform linear array virtual array element array con-figuration
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Quadratic integrability of solutions based on a class of delayed systems
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作者 计国君 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期630-638,共9页
Some properties such as oscillation, stability, existence of periodic solutions and quadratic integrability of solutions based on a class of second order nonlinear delayed systems are analyzed by using the V-function,... Some properties such as oscillation, stability, existence of periodic solutions and quadratic integrability of solutions based on a class of second order nonlinear delayed systems are analyzed by using the V-function, the Lyapunov functional or the Beuman-Bihari inequality, and some sufficient conditions based on those properties are given. Finally, the conclusions are applied to over-voltage models based on three-phase nonsynchronous closing of switches appearing in the power systems, the results in accord with the background physical meaning are obtained. And all the conditions of the conclusions are easy to validate, so the conclusions have definite theoretical meaning and are easy to apply in practice. 展开更多
关键词 nonlinear delayed system quadratic integrability periodic solution oscillatory solution OVERVOLTAGE
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A Feasible Approach for Improving Accuracy of Ground Deformation Measured by D-InSAR 被引量:8
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作者 CHANG Zhan-qiang GONG Hui-li +1 位作者 ZHANG Jing-fa GONG Li-xia 《Journal of China University of Mining and Technology》 EI 2007年第2期262-266,共5页
D-InSAR is currently one of the most popular research tools in the field of Microwave Remote Sensing. It is unrivaled in its aspect of measuring ground deformation due to its advantages such as high resolution,continu... D-InSAR is currently one of the most popular research tools in the field of Microwave Remote Sensing. It is unrivaled in its aspect of measuring ground deformation due to its advantages such as high resolution,continuous spa-tial-coverage and dynamics. However,there are still a few major problems to be solved urgently as a result of the intrin-sic complexity of this technique. One of the problems deals with improving the accuracy of measured ground deforma-tion. In this paper,various factors affecting the accuracy of ground deformation measured by D-InSAR are systemati-cally analyzed and investigated by means of the law of measurement error propagation. At the same time,we prove that the ground deformation error not only depends on the errors of perpendicular baselines as well as the errors of the inter-ferometric phase for topographic pair and differential pair,but also on the combination of the relationship of perpen-dicular baselines for topographic pairs and differential pairs. Furthermore,a feasible approach for improving the accu-racy of measured ground deformation is proposed,which is of positive significance in the practical application of D-InSAR. 展开更多
关键词 D-INSAR ground deformation perpendicular baseline interferometric phase
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Infeasibility Diagnosis on the Linear Programming Model of Production Planning in Refinery 被引量:1
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作者 李初福 何小荣 +3 位作者 陈丙珍 龚真直 陈勃 张秋怡 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第5期569-573,共5页
In order to effectively diagnose the infeasible linear programming (LP) model of production planning in refinery, the article proposed three stages strategy based on constraints’ classification and infeasibility anal... In order to effectively diagnose the infeasible linear programming (LP) model of production planning in refinery, the article proposed three stages strategy based on constraints’ classification and infeasibility analysis. Generally, infeasibility sources involve structural inconsistencies and data errors, and the data errors are further classified intoⅠ, Ⅱ and Ⅲ. The three stages strategy are: (1) Check data when they are inputted to detect data error Ⅰ and repair them; (2) Inspect data whether they are accorded with material balance before solving the LP model to identify data error Ⅱ and repair them; (3) Find irreducible inconsistent system of infeasible LP model and give diagnosis information priority-ranked to recognize data error Ⅲ and structural inconsistencies. These stages could be automatically executed by computer, and the approach has been applied to diagnose the infeasible model well in our graphic I/O petro-chemical industry modeling system. 展开更多
关键词 DIAGNOSIS INFEASIBILITY inconsistent constraints production planning
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AN ADAPTIVELY TRAINED KERNEL-BASED NONLINEAR REPRESENTOR FOR HANDWRITTEN DIGIT CLASSIFICATION 被引量:12
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作者 Liu Benyong Zhang Jing 《Journal of Electronics(China)》 2006年第3期379-383,共5页
In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recentl... In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recently presented nonlinear classifier for optimal pattern representation, so that its generalization ability may be evaluated in time-variant situation and a sparser representation is obtained for computationally intensive tasks. The addressed techniques are applied to handwritten digit classification to illustrate the feasibility for pattern recognition. 展开更多
关键词 Pattern recognition Handwritten digit recognition Incremental learning Sparse representation Kernel-based Nonlinear Representor (KNR)
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A Hierarchy of Lax Integrable Lattice Equations, Liouville Integrability and a NewIntegrable Symplectic Map 被引量:6
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作者 XUXi-Xiang ZHANGYu-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期321-328,共8页
A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discr... A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discrete Hamiltonian systems. A new integrable symplectic map is given by binary Bargmann constraint of the resulting hierarchy. Finally, an infinite set of conservation laws is given for the resulting hierarchy. 展开更多
关键词 lattice soliton equation discrete Hamiltonian system Liouville integrability NONLINEARIZATION symplctic map conservation law
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Integrability of Nonlinear Equations of Motion on Two-Dimensional World Sheet Space-Time 被引量:2
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作者 YAN Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期283-287,共5页
The integrability character of nonlinear equations of motion of two-dimensional gravity with dynamical torsion and bosonic string coupling is studied in this paper. The space-like and time-like first integrals of equa... The integrability character of nonlinear equations of motion of two-dimensional gravity with dynamical torsion and bosonic string coupling is studied in this paper. The space-like and time-like first integrals of equations of motion are also found. 展开更多
关键词 two-dimensional gravity model string coupling INTEGRABILITY
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A Solvable Model in Two—Dimensional Gravity Coupled to a Nonlinear Matter Field 被引量:3
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作者 YANJun TAOBi-You 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第1期19-21,共3页
The two-dimensional gravity model with a coupling constant and a vanishing cosmological constant coupled to a nonlinear matter field is investigated. We found that the classical equations of motion are exactly solvab... The two-dimensional gravity model with a coupling constant and a vanishing cosmological constant coupled to a nonlinear matter field is investigated. We found that the classical equations of motion are exactly solvable and the static solutions of the induced metric and scalar curvature can be obtained analytically. These solutions may be used to describe the naked singularity at the origin. 展开更多
关键词 solvable model two-dimensional gravity nonlinear matter field
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A novel method based on entransy theory for setting energy targets of heat exchanger network 被引量:5
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作者 Li Xia Yuanli Feng +1 位作者 Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第8期1037-1042,共6页
A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The ... A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The entransy recovery and entransy dissipation that are affected by temperature differences can be obtained through the shaded area under the composite curves.The method for setting the energy target of the HENs in T-Q diagram based on entransy theory is proposed.A case study of the diesel oil hydrogenation unit is used to illustrate the application of the method.The results show that three different heat transfer temperature differences is 10 K,15 K and 20 K,and the entransy recovery is 5.498×10~7k W·K,5.377×10~7k W·K,5.257×10~7k W·K,respectively.And the entransy transfer efficiency is 92.29%,91.63%,90.99%.Thus,the energy-saving potential of the HENs is obtained by setting the energy target based on the entransy transfer efficiency. 展开更多
关键词 Heat transfer Process systems Entransy Energy target T-Qdiagram
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