At present, China's demand for various energy sources is gradually increasing, and the demand for various conventional energy sources is gradually showing an upward trend. However, due to the limited resources, th...At present, China's demand for various energy sources is gradually increasing, and the demand for various conventional energy sources is gradually showing an upward trend. However, due to the limited resources, the development of sustainable energy sources will become an inevitable trend in the future market development. The establishment and improvement of wind power projects is more to effectively improve the development of energy. However, in the actual operation process, the wind power project itself has a relatively large impact on the environment, especially for some nature reserves, the ecological impact is particularly prominent. Therefore, as a research manager, it is necessary to deeply analyze and evaluate the direct impact of the wind power project on the ecological environment of the nature reserve under the existing working conditions. Based on the current evaluation model, this paper puts forward targeted measures to mitigate compensation, in order to speed up the transformation and optimization of working methods, realize the innovation of management methods, mitigate environmental conflicts, and increase the promotion and use of new energy sources. It also lays a solid foundation for the later development of market economy.展开更多
Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation mea...Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation measures have been proposed for accelerating post-earthquake recovery,their effects on building reconstruction are still unclear.This study aimed to analyze and evaluate the effects of compensation measures on post-earthquake building reconstruction.To achieve this objective,this study first identified the post-earthquake building reconstruction goals,21 reconstruction factors across five categories,and four compensation measures,and employed the methods of structural equation modeling,paired-samples t-test,and repeated measures analysis of variance to analyze the effects of reconstruction factors on the reconstruction goals and the effects of compensation measures on the reconstruction factors,respectively.A questionnaire was designed to investigate the post-earthquake building reconstruction projects in China,with 251 respondents participated.The results show that apart from project-specific condition,the other four categories of reconstruction factors,including owner condition,technology condition,resource availability,and contractor management capability,have significant effects on the reconstruction goals.The study also evaluated the extent of the above effects.On the other hand,the results indicate that the affecting extents of various compensation measures on reconstruction factors are significantly different.These findings can provide support and guidance for government management of post-earthquake building reconstruction and the development of compensation measures.They also provide a basis for future research on optimizing compensation measures for post-earthquake building reconstruction.展开更多
Automatic compensation of grinding wheel wear in dry grinding is accomplished by an image based online measurement method. A kind of PC-based charge-coupled device image recognition system is schemed out, which detect...Automatic compensation of grinding wheel wear in dry grinding is accomplished by an image based online measurement method. A kind of PC-based charge-coupled device image recognition system is schemed out, which detects the topography changes of the grinding wheel surface. Profile data, which corresponds to the wear and the topography, is measured by using a digital image processing method. The grinding wheel wear is evalualed by analyzing the position deviation of the grinding wheel edge. The online wear compensation is achieved according to the measure results. The precise detection and automatic compensation system is integrated into an open structure CNC curve grinding machine. A practical application is carried out to fulfil the precision curve grinding. The experimental results confirm the benefits of the proposed techniques, and the online detection accuracy is less than 5 um. The grinding machine provides higher precision according to the in-process grinding wheel error compensation.展开更多
A technique for compensating the errors of coordinate measuring machines (CMMs) with low stiffness is proposed. Some additional items related with the force deformation are introduced to the error compensation aquatio...A technique for compensating the errors of coordinate measuring machines (CMMs) with low stiffness is proposed. Some additional items related with the force deformation are introduced to the error compensation aquations. The research was carried on a moving colunm horizontal arm CMM. Experimental results show that both the effects of systematic components of error motions and force deformations are greatly reduced, which shows the effectiveness of proposed technique.展开更多
Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement, the measurement system is susceptible to non-linear error. In this...Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement, the measurement system is susceptible to non-linear error. In this work, we propose a convenient look-up-table-based （LUT-based） method to compensate for the non-linear error in captured fringe patterns. Without extra calibration, this LUT-based method completely utilizes the captured fringe pattern by recording the full-field differences. Then, a phase compensation map is established to revise the measured phase. Experimental results demonstrate that this method works effectively.展开更多
We present the thermal expansion coefficient （TEC） measurement technology of compensating for the effect of variations in the refractive index based on a Nd： YA G laser feedback system, the beam frequency is shifte...We present the thermal expansion coefficient （TEC） measurement technology of compensating for the effect of variations in the refractive index based on a Nd： YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.展开更多
A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relat...A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle.展开更多
Ultrasonic Lamb waves are considered as a sensitive and effective tool for nondestructive testing and evaluation of plate-like or pipe-like structures. The nature of multimode and dispersion causes the wave packets to...Ultrasonic Lamb waves are considered as a sensitive and effective tool for nondestructive testing and evaluation of plate-like or pipe-like structures. The nature of multimode and dispersion causes the wave packets to spread, and the modes overlap in both time and frequency domains as they propagate through the structures. By using a two-component laser interferometer technique, in combination with a priori knowledge of the dispersion characteristics and wave structure information of Lamb wave modes, a two-component signal processing technique is presented for implementing dispersion removal and mode separation simultaneously for two modes mixture signals of Lamb waves. The proposed algorithm is first processed and verified using synthetic Lamb wave signals. Then, the two-component displacements test experiment is conducted using different aluminum plate samples. Moreover, we confirm the effectiveness and robustness of this method.展开更多
Combining oven controlled technique,digital compensation,high-resolution frequency difference measurement and self-calibration technique,a new design method of precise oven controlled crystal oscillator（OCXO） is pro...Combining oven controlled technique,digital compensation,high-resolution frequency difference measurement and self-calibration technique,a new design method of precise oven controlled crystal oscillator（OCXO） is proposed.Fine compensation is made in the vicinity of the crystal temperature inflection point by using the non-real-time temperature compensation strategy,and self-calibration system is integrated in the crystal.The method improves the digital compensated phase noise,simplifies the traditional OCXO development system,reduces the cost and shortens the developing cycle.Experiment results show that with a standard reference signal and self-calibration updated data,the oscillator can work stable and achieve its best performence.The performance index of crystal oscillator had an improvement with one to two orders of magnitude on the basis of original technical index.The method is widely used in the improvement of high-end crystal oscillator and atomic clock.展开更多
This article deals with an averaging principle for Caputo fractional stochastic differential equations with compensated Poisson random measure.The main contribution of this article is impose some new averaging conditi...This article deals with an averaging principle for Caputo fractional stochastic differential equations with compensated Poisson random measure.The main contribution of this article is impose some new averaging conditions to deal with the averaging principle for Caputo fractional stochastic differential equations.Under these conditions,the solution to a Caputo fractional stochastic differential system can be approximated by that of a corresponding averaging equation in the sense ofmean square.展开更多
文摘At present, China's demand for various energy sources is gradually increasing, and the demand for various conventional energy sources is gradually showing an upward trend. However, due to the limited resources, the development of sustainable energy sources will become an inevitable trend in the future market development. The establishment and improvement of wind power projects is more to effectively improve the development of energy. However, in the actual operation process, the wind power project itself has a relatively large impact on the environment, especially for some nature reserves, the ecological impact is particularly prominent. Therefore, as a research manager, it is necessary to deeply analyze and evaluate the direct impact of the wind power project on the ecological environment of the nature reserve under the existing working conditions. Based on the current evaluation model, this paper puts forward targeted measures to mitigate compensation, in order to speed up the transformation and optimization of working methods, realize the innovation of management methods, mitigate environmental conflicts, and increase the promotion and use of new energy sources. It also lays a solid foundation for the later development of market economy.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.72204280)the Research and Innovation Team Support Program Funding Project of Central University of Finance and Economics(CUFE)(Grant No.CUFE-2021-GG-1)The authors are thankful for the support of NSFC and CUFE.
文摘Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation measures have been proposed for accelerating post-earthquake recovery,their effects on building reconstruction are still unclear.This study aimed to analyze and evaluate the effects of compensation measures on post-earthquake building reconstruction.To achieve this objective,this study first identified the post-earthquake building reconstruction goals,21 reconstruction factors across five categories,and four compensation measures,and employed the methods of structural equation modeling,paired-samples t-test,and repeated measures analysis of variance to analyze the effects of reconstruction factors on the reconstruction goals and the effects of compensation measures on the reconstruction factors,respectively.A questionnaire was designed to investigate the post-earthquake building reconstruction projects in China,with 251 respondents participated.The results show that apart from project-specific condition,the other four categories of reconstruction factors,including owner condition,technology condition,resource availability,and contractor management capability,have significant effects on the reconstruction goals.The study also evaluated the extent of the above effects.On the other hand,the results indicate that the affecting extents of various compensation measures on reconstruction factors are significantly different.These findings can provide support and guidance for government management of post-earthquake building reconstruction and the development of compensation measures.They also provide a basis for future research on optimizing compensation measures for post-earthquake building reconstruction.
基金This project is supported by Science and Technology Development Foundation of Shanghai Municipal Commission of Science and Technology, China (No.021111125).
文摘Automatic compensation of grinding wheel wear in dry grinding is accomplished by an image based online measurement method. A kind of PC-based charge-coupled device image recognition system is schemed out, which detects the topography changes of the grinding wheel surface. Profile data, which corresponds to the wear and the topography, is measured by using a digital image processing method. The grinding wheel wear is evalualed by analyzing the position deviation of the grinding wheel edge. The online wear compensation is achieved according to the measure results. The precise detection and automatic compensation system is integrated into an open structure CNC curve grinding machine. A practical application is carried out to fulfil the precision curve grinding. The experimental results confirm the benefits of the proposed techniques, and the online detection accuracy is less than 5 um. The grinding machine provides higher precision according to the in-process grinding wheel error compensation.
文摘A technique for compensating the errors of coordinate measuring machines (CMMs) with low stiffness is proposed. Some additional items related with the force deformation are introduced to the error compensation aquations. The research was carried on a moving colunm horizontal arm CMM. Experimental results show that both the effects of systematic components of error motions and force deformations are greatly reduced, which shows the effectiveness of proposed technique.
基金the financial support provided by the National Natural Science Foundation of China(11472267 and 11372182)the National Basic Research Program of China(2012CB937504)
文摘Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement, the measurement system is susceptible to non-linear error. In this work, we propose a convenient look-up-table-based （LUT-based） method to compensate for the non-linear error in captured fringe patterns. Without extra calibration, this LUT-based method completely utilizes the captured fringe pattern by recording the full-field differences. Then, a phase compensation map is established to revise the measured phase. Experimental results demonstrate that this method works effectively.
基金Supported by the National Natural Science Foundation of China under Grant No F050306
文摘We present the thermal expansion coefficient （TEC） measurement technology of compensating for the effect of variations in the refractive index based on a Nd： YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.
文摘A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle.
基金Project supported by the National Natural Science Foundation of China(Grant No.11374230)
文摘Ultrasonic Lamb waves are considered as a sensitive and effective tool for nondestructive testing and evaluation of plate-like or pipe-like structures. The nature of multimode and dispersion causes the wave packets to spread, and the modes overlap in both time and frequency domains as they propagate through the structures. By using a two-component laser interferometer technique, in combination with a priori knowledge of the dispersion characteristics and wave structure information of Lamb wave modes, a two-component signal processing technique is presented for implementing dispersion removal and mode separation simultaneously for two modes mixture signals of Lamb waves. The proposed algorithm is first processed and verified using synthetic Lamb wave signals. Then, the two-component displacements test experiment is conducted using different aluminum plate samples. Moreover, we confirm the effectiveness and robustness of this method.
基金Supported by the National Natural Science Foundation of China (10978017)the Open Fund of Key Laboratory of Time and Frequency Primary Standards (CAS)+2 种基金the Postdoctoral Grant of China (94469)the Basic and Advanced Technology Research Foundation of Hennan Province (122300410169)the Fundamental Research Funds for the Central Universities
文摘Combining oven controlled technique,digital compensation,high-resolution frequency difference measurement and self-calibration technique,a new design method of precise oven controlled crystal oscillator（OCXO） is proposed.Fine compensation is made in the vicinity of the crystal temperature inflection point by using the non-real-time temperature compensation strategy,and self-calibration system is integrated in the crystal.The method improves the digital compensated phase noise,simplifies the traditional OCXO development system,reduces the cost and shortens the developing cycle.Experiment results show that with a standard reference signal and self-calibration updated data,the oscillator can work stable and achieve its best performence.The performance index of crystal oscillator had an improvement with one to two orders of magnitude on the basis of original technical index.The method is widely used in the improvement of high-end crystal oscillator and atomic clock.
基金Zhongkai Guo supported by NSF of China(Nos.11526196,11801575)the Fundamental Research Funds for the Central Universities,South-Central University for Nationalities(Grant Number:CZY20014)+1 种基金Hongbo Fu is supported by NSF of China(Nos.11826209,11301403)Natural Science Foundation of Hubei Province(No.2018CFB688).
文摘This article deals with an averaging principle for Caputo fractional stochastic differential equations with compensated Poisson random measure.The main contribution of this article is impose some new averaging conditions to deal with the averaging principle for Caputo fractional stochastic differential equations.Under these conditions,the solution to a Caputo fractional stochastic differential system can be approximated by that of a corresponding averaging equation in the sense ofmean square.
