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Novel sucker rod pumping system based on linear motor technology

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Journal of Harbin Institute of Technology(New Series) 2004年第1期11卷 6-10页

作者：李立毅李立清吴红星胡余生邹积岩 dept. of electric engineering Harbin Institute of Technology Harbin 150001China dept. of electric engineering Dalian University of TechnologyDalian 116024China

Obtaining petroleum at the cost of electrical energy is a common problem in almost all oil fields, and it is mainly caused by low duty radio of induction motor used in beam pumping units. Traditional beam-pumping units have many intrinsic disadvantages such as low efficiency, complex transmission devices, poor flexibility, tremendous volume and weight in long stroke, ***, a novel direct driven linear electromagnetic pumping unit (EMPU) has been developed by combining oil extraction technology with linear motor technology. The thrust of EMPU matches the changing of suspension center load to improve the system efficiency and cut down the consumption of energy. Based on previous experience, a small-scale prototype was developed and a simulation was conducted with it. Both theoretical analyses and experimental study showed that the problems exiting in beam pumping units can be solved with EMPU system, and this is a new method which can be used to solve high energy waste in oil fields.

关键词： direct drive sucker rod pumping system electromagnetic pumping unit(EMPU) linear motor energy conservation

Study on least square modeling of heat engineering object based on typical signal response

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Journal of Harbin Institute of Technology(New Series) 2007年第1期14卷 1-4页

作者：齐维贵陈烈朱学莉 dept. of electric engineering Harbin Institute of Technology dept. of Electro-mechanical engineering University of Science and Technology of Suzhou

This paper proposes a kind of least square modeling method based on typical signal response to enhance modeling accuracy of heat engineering process and adapts the environment that modeling experiment conditions are limited. The principle of this method is, under the condition of known typical pulse, step and slope signal response and model structure, to give algorithm of model parameters of identified continuous system by least square mode through derivation. The method is applied to the identification of heat exchange process for a consumer substation, and identification result obtained is compared with that of other conventional methods. After the comparison the result shows that identification accuracy is improved obviously. In addition to the good identification accuracy, this method has the characteristics such as it can identify directly continuous system model, pure lagging time, and is not sensitive to data length in the identification process. All these characteristics show that this method is simple, easy to implement and has good practicability.

关键词： pulse response least square method heat engineering object identification

Seismic fragility assessment of existing sub-standard low strength reinforced concrete structures

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Earthquake engineering and engineering Vibration 2015年第3期14卷 439-452页

作者： Sohaib Ahmad Nicolas Kyriakides Kypros Pilakoutas Kyriacos Neocleous Qaiser uz Zaman dept. of Civil and Structural engineering University of Sheffield dept. of Civil engineering and Geomatics Cyprus University of Technology dept. of Civil and Environmental engineering University of Engineering and Technology

An analytical seismic fragility assessment framework is presented for the existing low strength reinforced concrete structures more common in the building stock of the developing *** realistic modelling of such substandard structures,low strength concrete stress-strain and bond-slip capacity models are included in calibrating material *** capacity parameters are generated stochastically to produce building population and cyclic pushover analysis is carried out to capture inelastic *** period values are evaluated corresponding to each displacement step on the capacity curves and used as seismic demand.A modified capacity demand diagram method is adopted for the degrading structures,which is further used to evaluate peak ground acceleration from back analysis considering each point on the capacity curve as performance *** developing fragility curves,the mean values of peak ground acceleration are evaluated corresponding to each performance point on the series of capacity curves.A suitable probability distribution function is adopted for the secant period scatter at different mean peak ground acceleration values and probability of exceedance of limit states is evaluated.A suitable regression function is used for developing fragility curves and regression coefficients are proposed for different confidence *** curves are presented for a low rise pre-seismic code reinforced concrete structure typical of developing countries.

关键词： analytical fragility damage index non-engineered b

Seismic risk assessment for developing countries: Pakistan as a case study

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Earthquake engineering and engineering Vibration 2018年第4期17卷 787-804页

作者： Shaukat A.Khan Kypros Pilakoutas Iman Hajirasouliha Reyes Garcia Maurizio Guadagnini dept. of Civil engineering Abasyn University dept. of Civil and Structural engineering The University of Sheffield

Modern Earthquake Risk Assessment（ERA） methods usually require seismo-tectonic information for Probabilistic Seismic Hazard Assessment（PSHA） that may not be readily available in developing countries. To bypass this drawback, this paper presents a practical event-based PSHA method that uses instrumental seismicity, available historical seismicity, as well as limited information on geology and tectonic setting. Historical seismicity is integrated with instrumental seismicity to determine the long-term hazard. The tectonic setting is included by assigning seismic source zones associated with known major faults. Monte Carlo simulations are used to generate earthquake catalogues with randomized key hazard parameters. A case study region in Pakistan is selected to demonstrate the effectiveness of the method. The results indicate that the proposed method produces seismic hazard maps consistent with previous studies, thus being suitable for generating such maps in regions where limited data are available. The PSHA procedure is developed as an integral part of an ERA framework named EQRAM. The framework is also used to determine seismic risk in terms of annual losses for the study region.

关键词： recycled concrete frame-shear wall concealed bracings shaking table test nonlinear time-history responseanalysis

Evaluating location specific strain rates, temperatures,and accumulated strains in friction welds through microstructure modeling

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Defence Technology（防务技术） 2018年第2期14卷 83-92页

作者： Javed Akram Prasad Rao Kalvala Vikas Jindal Mano Misra dept. of Metallurgical engineering University of Utah dept. of Metallurgical engineering Indian Institute of Technology(BHU)

A microstructural simulation method is adopted to predict the location specific strain rates, temperatures, grain evolution, and accumulated strains in the Inconel 718 friction welds. Cellular automata based 2D microstructure model was developed for Inconel 718 alloy using theoretical aspects of dynamic recrystallization. Flow curves were simulated and compared with experimental results using hot deformation parameter obtained from literature work. Using validated model, simulations were performed for friction welds of Inconel 718 alloy generated at three rotational speed i.e., 1200, 1500, and1500 RPM. Results showed the increase in strain rates with increasing rotational speed. These simulated strain rates were found to match with the analytical results. Temperature difference of 150 K was noticed from center to edge of the weld. At all the rotational speeds, the temperature was identical implying steady state temperature(0.89 T_m) attainment.

关键词： Microstructure modeling Dynamic recrystallization Friction welding Inconel 718 EBSD Hot deformation Strain map

Typical application of Rogowski coils in inspection of electrobath

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Journal of Harbin Institute of Technology(New Series) 2004年第1期11卷 103-108页

作者：郭红贾正春 dept. of electric engineering Huazhong University of Science and Technology Wuhan 430074 China

During the aluminum electrolytic roasting process,each component of the electrobath of aluminum performs unsteadily when the electrolytic bath is in the pre-roasting stage. It is important to monitor the currents of the anodes and the cathodes of the aluminum electrobath at regular intervals. Both practice and investigation indicate that Rogowski coil can be adopted to measure heavy direct current of the anodes and the cathodes of the aluminum electrobath. The paper not only introduces the typical application of the Rogowski coil to inspect the state of aluminum electrobath in the roasting process, but also analyzes the principles of the coil sensor including its dynamic properties and some important measurement results respectively. The optimal parameters of the coil can be simulated by means of an advanced simulation tool: simulink tools based on MATLAB soft environment. Based on the gathered current data, an even-current coefficient has been introduced, and the current curve can be drawn. Since they are applied in AL-Electrolyzing, it is possible to distinguish the anode of which the current is not evenly distributed, and to take adjusting measures over a period of time to ensure that the current is evenly distributed.

关键词： rogowski coil current monitoring system simulation even current distribution dilapidation detection

Optimal operation of cascaded hydroelectric power plants in the power market

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Journal of Harbin Institute of Technology(New Series) 2004年第6期11卷 614-617页

作者：蔡兴国马平林士颖 dept. of electric engineering Harbin Institute of Technology Harbin 150001 China

An improved network flow algorithm, which includes the minimum cost network flow and the same period network flow, is proposed to solve the optimization of cascaded hydroelectric power plants in a competitive electricity market. The typical network flow is used to find the feasible flow and add the discharge water to different cascaded hydroelectric power plants at the same step. The same period network flow is used to find the optimal flow and add the power output at a different step. This new algorithm retains the advantages of the typical network flow, such as simplicity and ease of realization. The result of the case analysis indicates that the new algorithm can achieve high calculation precision and can be used to calculate the optimal operation of cascaded hydroelectric power plants.

关键词： cascaded hydroelectric power plants network flow market clearing price

A new spatial coherence model and analytical coeffi cients for multi-support response spectrum combination

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Earthquake engineering and engineering Vibration 2007年第3期6卷 225-235页

作者：王君杰陈虎 dept. of Bridge engineering Tongji University

In this paper, a new spatial coherence model of seismic ground motions is proposed by a fitting procedure. The analytical expressions of modal combination （correlation） coefficients of structural response are developed for multi-support seismic excitations. The coefficients from both the numerical integration and analytical solutions are compared to verify the accuracy of the solutions. It is shown that the analytical expressions of numerical modal combination coefficients are of high accuracy. The results of random responses of an example bridge show that the analytical modal combination coefficients developed in this paper are accurate enough to meet the requirements needed in practice. In addition, the computational efficiency of the analytical solutions of the modal combination coefficients is demonstrated by the response computation of the example bridge. It is found that the time required for the structural response analysis by using the analytical modal combination coefficients is less than 1/20 of that using numerical integral methods.

关键词： multi-support seismic excitations spatial coherence model modal combination coefficients computational efficiency power spectrum density

Linearly constrained SOLMS for adaptive space-time interference cancellation in STBC MIMO systems

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Journal of Harbin Institute of Technology(New Series) 2008年第2期15卷 176-178页

作者：单红梅胡光锐 dept.of Electronic engineering Shanghai University of Electric Power dept. of Electronic engineering Shanghai Jiaotong University

This paper presents an adaptive linearly constrained second-order least mean-square (LC-SOLMS) algorithm for interference cancellation in space-time block coded MIMO systems with fading channels. By taking mean-output-energy (MOE) optimization method, an adaptive linear detection algorithm was built up, which can suppress multiple access interference and noise. Simulation results illustrate that the proposed algorithm has great interference cancellation capability and faster convergence performance.

关键词： soace-time block code MIMO adaotive interference cancellation MOE