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SWOT Analysis and Recommendations for Enhancing Sino-Russian Agricultural Trade Cooperation
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作者 Huilan Fang 《Proceedings of Business and Economic Studies》 2024年第2期163-169,共7页
With the outbreak of the Russian-Ukraine conflict,the changes in agricultural trade between China and Russia are receiving more and more attention.This study analyzes the current status of Sino-Russian agricultural tr... With the outbreak of the Russian-Ukraine conflict,the changes in agricultural trade between China and Russia are receiving more and more attention.This study analyzes the current status of Sino-Russian agricultural trade and employs a SWOT analysis to explore the strengths,weaknesses,opportunities,and threats within their agricultural trading activities.The findings suggest there are opportunities for further optimization and enhancement in the Sino-Russian agricultural trade.Based on this,suggestions proposed include accelerating the development of transportation hubs,facilitating agricultural trade,refining legal frameworks for agricultural exports,and expediting the establishment of economic cooperation zones. 展开更多
关键词 Trade scale Trade structure SWOT analysis Countermeasures and suggestions
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Data envelopment analysis for scale elasticity measurement in the stochastic case:with an application to Indian banking
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作者 Alireza Amirteimoori Biresh K.Sahoo Saber Mehdizadeh 《Financial Innovation》 2023年第1期955-990,共36页
In the nonparametric data envelopment analysis literature,scale elasticity is evaluated in two alternative ways:using either the technical efficiency model or the cost efficiency model.This evaluation becomes problema... In the nonparametric data envelopment analysis literature,scale elasticity is evaluated in two alternative ways:using either the technical efficiency model or the cost efficiency model.This evaluation becomes problematic in several situations,for example(a)when input proportions change in the long run,(b)when inputs are heterogeneous,and(c)when firms face ex-ante price uncertainty in making their production decisions.To address these situations,a scale elasticity evaluation was performed using a value-based cost efficiency model.However,this alternative value-based scale elasticity evaluation is sensitive to the uncertainty and variability underlying input and output data.Therefore,in this study,we introduce a stochastic cost-efficiency model based on chance-constrained programming to develop a value-based measure of the scale elasticity of firms facing data uncertainty.An illustrative empirical application to the Indian banking industry comprising 71 banks for eight years(1998–2005)was made to compare inferences about their efficiency and scale properties.The key findings are as follows:First,both the deterministic model and our proposed stochastic model yield distinctly different results concerning the efficiency and scale elasticity scores at various tolerance levels of chance constraints.However,both models yield the same results at a tolerance level of 0.5,implying that the deterministic model is a special case of the stochastic model in that it reveals the same efficiency and returns to scale characterizations of banks.Second,the stochastic model generates higher efficiency scores for inefficient banks than its deterministic counterpart.Third,public banks exhibit higher efficiency than private and foreign banks.Finally,public and old private banks mostly exhibit either decreasing or constant returns to scale,whereas foreign and new private banks experience either increasing or decreasing returns to scale.Although the application of our proposed stochastic model is illustrative,it can be potentially applied to all firms in the information and distribution-intensive industry with high fixed costs,which have ample potential for reaping scale and scope benefits. 展开更多
关键词 Data envelopment analysis Stochastic data envelopment analysis Technical efficiency Returns to scale Economies of scale Scale elasticity Indian banking ECONOMETRICS ECONOMICS
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Assessment of hindlimb motor recovery affer severe thoracic spinal cord injury in rats: classification of CatWalk XT■ gait analysis parameters 被引量:1
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作者 Guoli Zheng Hao Zhang +6 位作者 Mohamed Tail Hao Wang Johannes Walter Thomas Skutella Andreas Unterberg Klaus Zweckberger Alexander Younsi 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1084-1089,共6页
Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used an... Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency. 展开更多
关键词 Basso Beattie and Bresnahan rating scale behavioral assessment CatWalk XT■gait analysis contusive and compressive injury hindlimb motor function histological changes spinal cord injury spontaneous recovery THORACIC weight
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Modified scaled distance regression analysis approach for prediction of blast-induced ground vibration in multi-hole blasting 被引量:10
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作者 Hemant Agrawal A.K.Mishra 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第1期202-207,共6页
The blast-induced ground vibration prediction using scaled distance regression analysis is one of the most popular methods employed by engineers for many decades. It uses the maximum charge per delay and distance of m... The blast-induced ground vibration prediction using scaled distance regression analysis is one of the most popular methods employed by engineers for many decades. It uses the maximum charge per delay and distance of monitoring as the major factors for predicting the peak particle velocity(PPV). It is established that the PPV is caused by the maximum charge per delay which varies with the distance of monitoring and site geology. While conducting a production blasting, the waves induced by blasting of different holes interfere destructively with each other, which may result in higher PPV than the predicted value with scaled distance regression analysis. This phenomenon of interference/superimposition of waves is not considered while using scaled distance regression analysis. In this paper, an attempt has been made to compare the predicted values of blast-induced ground vibration using multi-hole trial blasting with single-hole blasting in an opencast coal mine under the same geological condition. Further,the modified prediction equation for the multi-hole trial blasting was obtained using single-hole regression analysis. The error between predicted and actual values of multi-hole blast-induced ground vibration was found to be reduced by 8.5%. 展开更多
关键词 Peak particle velocity(PPV) Blast-induced ground vibration Scaled distance regression analysis Wave SUPERIMPOSITION SINGLE-HOLE BLASTING
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Analysis and forecasts of investment scale and structure in upstream sector for oil companies based on system dynamics 被引量:2
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作者 Zhang Baosheng Wang Qing 《Petroleum Science》 SCIE CAS CSCD 2011年第1期120-126,共7页
Oil and gas exploration and production is the most important and key segment in the whole business chain of the petroleum industry.Therefore,oil companies always put much emphasis on making scientific and reasonable d... Oil and gas exploration and production is the most important and key segment in the whole business chain of the petroleum industry.Therefore,oil companies always put much emphasis on making scientific and reasonable decisions about investment scale and structure in the upstream sector,so that they can minimise business risks and obtain high returns.According to the system dynamics theories and methods and based on the actual results from an oil company's practice in China,a system dynamics model is built in this paper for analyzing and forecasting the upstream investment scale and structure for an oil company.This model was used to analyze the investment effect of a large oil company in China, and the results showed that the total upstream investment scale will decline slowly in a short period and the investment proportion of different parts should be adjusted if some influencing factors are taken into account.This application practice was compared with the actual data and indicated that the system dynamics(SD) model presented in this paper is a useful tool for analyzing and forecasting of upstream investment scale and structure of oil companies in their investment decisions. 展开更多
关键词 Oil companies upstream investment scale and structure analysis and forecast system dynamics
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Modified slow-fast analysis method for slow-fast dynamical systems with two scales in frequency domain 被引量:1
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作者 Zhengdi Zhang Zhangyao Chen Qinsheng Bi 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期358-362,共5页
A modified slow-fast analysis method is presented for the periodically excited non-autonomous dynamical system with an order gap between the exciting frequency and the natural frequency.By regarding the exciting term ... A modified slow-fast analysis method is presented for the periodically excited non-autonomous dynamical system with an order gap between the exciting frequency and the natural frequency.By regarding the exciting term as a slow-varying parameter,a generalized autonomous fast subsystem can be defined,the equilibrium branches as well as the bifurcations of which can be employed to account for the mechanism of the bursting oscillations by combining the transformed phase portrait introduced.As an example,a typical periodically excited Hartley model is used to demonstrate the validness of the method,in which the exciting frequency is far less than the natural frequency.The equilibrium branches and their bifurcations of the fast subsystem with the variation of the slow-varying parameter are presented.Bursting oscillations for two typical cases are considered,which reveals that,fold bifurcation may cause the the trajectory to jump between different equilibrium branches,while Hopf bifurcation may cause the trajectory to oscillate around the stable limit cycle. 展开更多
关键词 TWO scales in frequency domain MODIFIED slow-fast analysis METHOD BURSTING oscillations Bifurcation mechanism
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Enhanced Sentiment Analysis Algorithms for Multi-Weight Polarity Selection on Twitter Dataset
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作者 Ayman Mohamed Mostafa 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期1015-1034,共20页
Sentiment analysis is based on the orientation of user attitudes and satisfaction towards services and subjects.Different methods and techniques have been introduced to analyze sentiments for obtaining high accuracy.T... Sentiment analysis is based on the orientation of user attitudes and satisfaction towards services and subjects.Different methods and techniques have been introduced to analyze sentiments for obtaining high accuracy.The sentiment analysis accuracy depends mainly on supervised and unsupervised mechanisms.Supervised mechanisms are based on machine learning algorithms that achieve moderate or high accuracy but the manual annotation of data is considered a time-consuming process.In unsupervised mechanisms,a lexicon is constructed for storing polarity terms.The accuracy of analyzing data is considered moderate or low if the lexicon contains small terms.In addition,most research methodologies analyze datasets using only 3-weight polarity that can mainly affect the performance of the analysis process.Applying both methods for obtaining high accuracy and efficiency with low user intervention during the analysis process is considered a challenging process.This paper provides a comprehensive evaluation of polarity weights and mechanisms for recent sentiment analysis research.A semi-supervised framework is applied for processing data using both lexicon and machine learning algorithms.An interactive sentiment analysis algorithm is proposed for distributing multi-weight polarities on Arabic lexicons that contain high morphological and linguistic terms.An enhanced scaling algorithm is embedded in the multi-weight algorithm to assign recommended weight polarities automatically.The experimental results are conducted on two datasets to measure the over-all accuracy of proposed algorithms that achieved high results when compared to machine learning algorithms. 展开更多
关键词 Sentiment analysis semi-supervised framework multi-weight polarity algorithm Arabic lexicons and automated scaling algorithm
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Analysis of mental health status and related factors in patients with acute cerebral infarction
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作者 Qing-Qin Chen Fu-Mei Lin +5 位作者 Dan-Hong Chen Yi-Min Ye Guo-Mei Gong Fen-Fei Chen Su-Fen Huang Shan-Ling Peng 《World Journal of Psychiatry》 SCIE 2023年第10期793-802,共10页
BACKGROUND Acute cerebral infarction(ACI)is characterized by a high incidence of morbidity,disability,recurrence,death and heavy economic burden,and has become a disease of concern in global researchers.As ACI has ser... BACKGROUND Acute cerebral infarction(ACI)is characterized by a high incidence of morbidity,disability,recurrence,death and heavy economic burden,and has become a disease of concern in global researchers.As ACI has serious effects on patients’physical status,life and economy,often causing anxiety,depression and other psychological problems,these problems can lead to the aggravation of physical symptoms;thus,it is very important to understand the factors affecting the mental health of these patients.AIM To understand the elements that affect the mental health of patients who have suffered an ACI.METHODS A questionnaire survey was conducted among patients with ACI admitted to three tertiary hospitals(Quanzhou First Hospital,Fuqing City Hospital Affiliated to Fujian Medical University,and the 900 Hospital of the Joint Service Support Force of the People’s Liberation Army of China)in Fujian Province from January 2022 to December 2022 using the convenience sampling method.ACI inpatients who met the inclusion criteria were selected.Informed consent was obtained from the patients before the investigation,and a face-to-face questionnaire survey was conducted using a unified scale.The questionnaire included a general situation questionnaire,Zung’s self-rating depression scale and Zung’s self-rating anxiety scale.All questionnaires were checked by two researchers and then the data were input and sorted using Excel software.The general situation of patients with ACI was analyzed by descriptive statistics,the influence of variables on mental health by the independent sample t test and variance analysis,and the influencing factors on psychological distress were analyzed by multiple stepwise regression.RESULTS The average age of the 220 patients with ACI was 68.64±10.74 years,including 142 males and 78 females.Most of the patients were between 60 and 74 years old,the majority had high school or technical secondary school education,most lived with their spouse,and most lived in cities.The majority of patients had a personal income of 3001 to 5000 RMB yuan per month.The new rural cooperative medical insurance system had the largest number of participants.Most stroke patients were cared for by their spouses and of these patients,52.3%had previously smoked.Univariate analysis showed that gender,age,residence,course of disease,number of previous chronic diseases and smoking history were the main factors affecting the anxiety scores of patients with ACI.Age,living conditions,monthly income,course of disease and knowledge of disease were the primary variables influencing the depression score in patients with ACI.The findings of multivariate analysis revealed that the course of disease and gender were the most important factors influencing patients’anxiety scores,and the course of disease was also the most important factor influencing patients’depression scores.CONCLUSION Long disease course and female patients with ACI were more likely to have psychological problems such as a high incidence of emotional disorders.These groups require more attention and counseling. 展开更多
关键词 Acute cerebral infarction Mental health Self-rating depression scale Self-rating anxiety scale Influencing factor Correlation analysis
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Melt Index Prediction by Neural Soft-Sensor Based on Multi-Scale Analysis and Principal Component Analysis 被引量:11
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作者 施健 刘兴高 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期849-852,共4页
熔体流动指数( MI )的预言,在决定产品的最重要的参数“ s 等级和在实际工业进程生产的聚丙烯的质量管理, isstudied.A 小说有主要组分分析( PCA )的软传感器的模型,光线的基础函数( RBF )网络,并且多尺度的分析( MSA )被建议从真... 熔体流动指数( MI )的预言,在决定产品的最重要的参数“ s 等级和在实际工业进程生产的聚丙烯的质量管理, isstudied.A 小说有主要组分分析( PCA )的软传感器的模型,光线的基础函数( RBF )网络,并且多尺度的分析( MSA )被建议从真实进程变量推断生产产品的 MI ,在 PCA 被执行选择最相关的进程特征并且消除输入变量的关联的地方, MSA 被介绍获得更多信息并且减少系统的不确定性,并且 RBF 网络被用来描绘这进程的非线性。研究结果证明建议方法提供有希望的预言可靠性和精确性,并且想了在丙烯聚合过程有广泛的应用程序前景。 展开更多
关键词 多尺度分析 主元分析 聚丙烯 熔融指数 神经元软测量 预报模型
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Scale-Dependent Representations of Relief Based on Wavelet Analysis 被引量:4
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作者 WU Fan 《Geo-Spatial Information Science》 2003年第1期66-69,共4页
Automatic generalization of geographic information is the core of multi_scale representation of spatial data,but the scale_dependent generalization methods are far from abundant because of its extreme complicacy.This ... Automatic generalization of geographic information is the core of multi_scale representation of spatial data,but the scale_dependent generalization methods are far from abundant because of its extreme complicacy.This paper puts forward a new consistency model about scale_dependent representations of relief based on wavelet analysis,and discusses the thresholds in the model so as to acquire the continual representations of relief with different details between scales.The model not only meets the need of automatic generalization but also is scale-dependent completely.Some practical examples are given. 展开更多
关键词 数字高程模型 地理信息系统 空间数据 小波分析 DEM 地理数据
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Direct scaling of residual displacements for bilinear and pinching oscillators
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作者 Mohammad Saifullah Vinay K.Gupta 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期129-149,共21页
The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displ... The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the event.An attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model parameters.None of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not available.The statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model alone.The proposed scaling model is applicable to horizontal ground motions in the western U.S.for earthquake magnitudes less than 7 or epicentral distances greater than 20 km. 展开更多
关键词 residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model
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Numerical Analysis of a Spiral-groove Dry-gas Seal Considering Micro-scale Effects 被引量:12
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作者 WANG Bing ZHANG Huiqiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期146-153,共8页
A dry-gas seal system is a non-contact seal technology that is widely used in different industrial applications.Spiral-groove dry-gas seal utilizes fluid dynamic pressure effects to realize the seal and lubrication pr... A dry-gas seal system is a non-contact seal technology that is widely used in different industrial applications.Spiral-groove dry-gas seal utilizes fluid dynamic pressure effects to realize the seal and lubrication processes,while forming a high pressure gas film between two sealing faces due to the deceleration of the gas pumped in or out.There is little research into the effects and the influence on seal performance,if the grooves and the gas film are at the micro-scale.This paper investigates the micro-scale effects on spiral-groove dry-gas seal performance in a numerical solution of a corrected Reynolds equation.The Reynolds equation is discretized by means of the finite difference method with the second order scheme and solved by the successive-over-relaxation(SOR) iterative method.The Knudsen number of the flow in the sealing gas film is changed from 0.005 to 0.120 with a variation of film depth and sealing pressure.The numerical results show that the average pressure in the gas film and the sealed gas leakage increase due to micro-scale effects.The open force is enlarged,while the gas film stiffness is significantly decreased due to micro-scale effects.The friction torque and power consumption remain constant,even in low sealing pressure and spin speed conditions.In this paper,the seal performance at different rotor face spin speeds is also described.The proposed research clarifies the micro-scale effects in a spiral-groove dry-gas seal and their influence on seal performance,which is expected to be useful for the improvement of the design of dry-gas seal systems operating in the slip flow regime. 展开更多
关键词 micro-scale effect spiral-groove dry-gas seal numerical analysis Reynolds equation
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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Numerical Simulation for Accuracy of Velocity Analysis in Small-Scale High-Resolution Marine Multichannel Seismic Technology 被引量:5
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作者 LUO Di CAI Feng WU Zhiqiang 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第3期370-382,共13页
When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positi... When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration. 展开更多
关键词 小规模 高分辨率 多信道地震 速度分析精确性 煤气的水合物
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Multi-scale analysis of earthquake activity in Chinese mainland 被引量:1
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作者 SHAO Hui-cheng(邵辉成) +7 位作者 DU Chang-e(杜长娥) LIU Zhi-hui(刘志辉) SUN Yan-xue(孙彦雪) XIA Chang-qi(夏长起) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第1期109-113,共5页
Identifying the active and inactive period of earthquakes in Chinese mainland is of great importance for guiding mid-short term, especially short term, earthquake forecast.……
关键词 multi-scale analysis wavelet analysis Chinese mainland
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SIMULATION OF CRACK DIAGNOSIS OF ROTOR BASED ON MULTI-SCALE SINGUUR-SPECTRUM ANALYSIS 被引量:4
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作者 LI Ruqiang LIU Yuanfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第2期282-285,共4页
In the diagnosis of rotor crack based on wavelet analysis, it is a painful task to find out an adaptive mother wavelet as many of them can be chosen and the analytic results of different mother wavelets are yet not th... In the diagnosis of rotor crack based on wavelet analysis, it is a painful task to find out an adaptive mother wavelet as many of them can be chosen and the analytic results of different mother wavelets are yet not the same. For this limitation of wavelet analysis, a novel diagnostic approach of rotor crack based on multi-scale singular-spectrum analysis (MS-SSA) is proposed. Firstly, a Jeffcott model of a cracked rotor is developed and the forth-order Runge-Kutta method is used to solve the motion equations of this rotor to obtain its time response (signals). Secondly, a comparatively simple approach of MS-SSA is presented and the empirical orthogonal functions of different orders in various scales are regarded as analyzing functions. At last, the signals of the cracked rotor and an uncracked rotor are analyzed using the proposed approach of MS-SSA, and the simulative results are compared. The results show that, the data-adaptive analyzing functions can capture many features of signals and the rotor crack can be identified and diagnosed effectively by comparing the analytic results of signals of the cracked rotor with those of the uncracked rotor using the analyzing functions of different orders. 展开更多
关键词 ROTOR CRACK Fault diagnosis Multi-scale singular-spectrum analysis(MS-SSA)
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Temporal and Spatial Scale Dependence of Precipitation Analysis over the Tropical Deep Convective Regime
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作者 沈新勇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1390-1394,共5页
Data from Goddard cumulus ensemble model experiment are used to study temporal and spatial scale dependence of tropical rainfall separation analysis based on cloud budget during Tropical Ocean Global Atmosphere Couple... Data from Goddard cumulus ensemble model experiment are used to study temporal and spatial scale dependence of tropical rainfall separation analysis based on cloud budget during Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment (TOGA COARE). The analysis shows that the calculations of model domain mean or time-mean grid-scale mean simulation data overestimate the rain rates of the two rainfall types associated with net condensation but they severely underestimate the rain rate of the rainfall type associated with net evaporation and hydrometeor convergence. 展开更多
关键词 cloud microphysical budget temporal and spatial scale rainfall partitioning analysis
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Reliability Sensitivity Analysis for Location Scale Family
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作者 洪东跑 张海瑞 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第3期188-192,共5页
Many products always operate under various complex environment conditions. To describe the dynamic influence of environment factors on their reliability, a method of reliability sensitivity analysis is proposed. In th... Many products always operate under various complex environment conditions. To describe the dynamic influence of environment factors on their reliability, a method of reliability sensitivity analysis is proposed. In this method, the location parameter is assumed as a function of relevant environment variables while the scale parameter is assumed as an unknown positive constant. Then, the location parameter function is constructed by using the method of radial basis function. Using the varied environment test data, the log-likelihood function is transformed to a generalized linear expression by describing the indicator as Poisson variable. With the generalized linear model, the maximum likelihood estimations of the model coefficients are obtained. With the reliability model, the reliability sensitivity is obtained. An instance analysis shows that the method is feasible to analyze the dynamic variety characters of reliability along with environment factors and is straightforward for engineering application. 展开更多
关键词 system engineering RELIABILITY sensitivity analysis environment factor location scale family radial basis function generalized linear model
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Cost-benefit Analysis of Scale Pig Breeding in Shandong Province Based on Modified Entropy Weight-TOPSIS Model
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作者 Yuanyuan ZHANG Shimin SUN 《Asian Agricultural Research》 2014年第8期21-25,共5页
According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding ... According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province. 展开更多
关键词 PIG SCALE BREEDING COST-BENEFIT analysis TOPSIS mo
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Two‑parameter dynamical scaling analysis of single‑phase natural circulation in a simple rectangular loop based on dilation transformation
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作者 Jia‑Ning Xu Xiang‑Bin Li +3 位作者 Yu‑Sheng Liu Shuai Yang De‑Chen Zhang Qiao Wu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期59-74,共16页
Scaling analysis is widely used to design scaled-down experimental facilities through which the prototype phenomena can be effectively evaluated.As a new method,dynamic system scaling(DSS)must be verified as a rationa... Scaling analysis is widely used to design scaled-down experimental facilities through which the prototype phenomena can be effectively evaluated.As a new method,dynamic system scaling(DSS)must be verified as a rational and applicable method.A DSS method based on dilation transformation was evaluated using single-phase natural circulation in a simple rectangular loop.The scaled-down cases were constructed based on two parameters—length ratio and dilation number—and the corresponding transient processes were simulated using the Relap5 computational code.The results show that this DSS method can simulate the dynamic flow characteristics of scaled-down cases.The transient deviation of the temperature difference and mass flow rate of the scaled cases decrease with increases in the length ratio and dilation number.The distortion of the transient temperature difference is smaller than that of the mass flow;however,the overall deviation is within a reasonable range. 展开更多
关键词 Dynamical system scaling analysis Single-phase natural circulation Transient scaling deviation Dilation transformation
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