In manganese electrolysis,electrochemical oscillations and manganese dendrite growth are typical nonlinear phenomena critical for energy consumption reduction.Nonetheless,existing research lacks a deep understanding o...In manganese electrolysis,electrochemical oscillations and manganese dendrite growth are typical nonlinear phenomena critical for energy consumption reduction.Nonetheless,existing research lacks a deep understanding of their underlying mechanisms.In this study,we systematically explored the evolution of anode electrochemical oscillations during manganese electrolysis and designed a square wave circuit to effectively suppress oscillations and dendrite growth while reducing energy consumption.A novel four-dimensional differential equation was introduced to explore the internal dynamic mechanisms of typical nonlinear behaviors.The experimental results showed that while the evolutionary patterns of current and potential oscillation signals were consistent,their waveform directions were opposite.The square wave current effectively suppressed both electrochemical oscillations and the growth of manganese dendrites.Furthermore,compared to direct current electrolysis,the square wave current improved the current efficiency by 3.6%and reduced the energy consumption by 0.32 kW·h·kg^(−1).展开更多
Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively ...Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively high row weights,the existing blind recognition algorithms based on a candidate set generally perform worse.In this paper,we propose a blind recognition method for LDPC codes,called as tangent function assisted least square(TLS)method,which improves recognition performances by constructing a new cost function.To characterize the constraint degree among received vectors and paritycheck vectors,a feature function based on tangent function is constructed in the proposed algorithm.A cost function based on least square method is also established according to the feature function values satisfying the parity-check relationship.Moreover,the minimum average value in TLS is obtained on the candidate set.Numerical analysis and simulation results show that recognition performances of TLS algorithm are consistent with theoretical results.Compared with existing algorithms,the proposed method possesses better recognition performances.展开更多
Partial least squares (PLS) model maximizes the covariance between process variables and quality variables,making it widely used in quality-related fault detection.However,traditional PLS methods focus primarily on li...Partial least squares (PLS) model maximizes the covariance between process variables and quality variables,making it widely used in quality-related fault detection.However,traditional PLS methods focus primarily on linear processes,leading to poor performance in dynamic nonlinear processes.In this paper,a novel quality-related fault detection method,named DiCAE-PLS,is developed by combining dynamic-inner convolutional autoencoder with PLS.In the proposed DiCAE-PLS method,latent features are first extracted through dynamic-inner convolutional autoencoder (DiCAE) to capture process dynamics and nonlinearity from process variables.Then,a PLS model is established to build the relationship between the extracted latent features and the final product quality.To detect quality-related faults,Hotelling's T^(2) statistic is employed.The developed quality-related fault detection is applied to the widely used industrial benchmark of the Tennessee.展开更多
The identification of rock mass hazard sources is fundamental for preventing rockfall and landslide disasters in mountainous regions,with rock mass structural characteristics playing a vital role in hazard assessment....The identification of rock mass hazard sources is fundamental for preventing rockfall and landslide disasters in mountainous regions,with rock mass structural characteristics playing a vital role in hazard assessment.In this study,terrestrial laser scanning(TLS)and unmanned aerial vehicle(UAV)technologies were integrated to enhance the evaluation methodology for rock mass hazard sources,focusing on the Sichuan Yanjiang Expressway project in China.The findings demonstrate that TLS-UAV technology enhanced both spatial coverage and data density in slope modeling.Through integrated algorithmic analysis,rock discontinuities within heterogeneous datasets were systematically identified,enabling quantitative extraction and statistical analysis of key geometric parameters,including orientation,trace length,spacing,and roughness.Furthermore,quantitative models were developed for cohesion,friction angle and the morphology parameter M of in situ discontinuities,respectively,facilitating efficient mechanical parameter acquisition.A novel rock mass hazard index(RHI)was developed incorporating discontinuity geometric rating(DGR),discontinuity mechanical rating(DMR),and slope mass rating(SMR).Field validation confirmed the methodology's effectiveness in evaluating risk levels and spatial heterogeneity of rock mass hazard sources,revealing the contribution of different discontinuity sets to the rock mass hazard and identifying the primary discontinuity sets controlling instability mechanisms.This study is of great significance for evaluating discontinuity-controlled rock mass hazard sources and preventing rockfall disasters.展开更多
针对实际点云数据中存在的噪点与缺陷对拟合平面时带来的影响,提出一种基于最小平方中值算法(least median of squares,LMedS)与距离加权总体最小二乘法(weighted total least squares based on distance,WTLSD)相结合的平面拟合算法。...针对实际点云数据中存在的噪点与缺陷对拟合平面时带来的影响,提出一种基于最小平方中值算法(least median of squares,LMedS)与距离加权总体最小二乘法(weighted total least squares based on distance,WTLSD)相结合的平面拟合算法。通过最小平方中值算法初步去除点云中的噪点,并基于距离构建初始权重矩阵,利用距离加权总体最小二乘法对点云进行平面拟合,减少平面中凸起与凹陷等缺陷对平面拟合的影响,该算法与传统平面拟合算法相比具备消除异常点与平面缺陷的优点,具备更高的拟合精度;与随机采样一致性算法(random sample consensus,RANSAC)相比具有更高的拟合效率与相近的拟合精度。展开更多
为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决...为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决定分解模态数和带宽,结合最小二乘-旋转不变技术(total least square-estimating signal parameter via rotational invariance techniques,TLS-ESPRIT)对分解出的振荡分量进行参数辨识,无需另外使用降噪算法。通过复合信号测试法、PSCAD/EMTDC电磁暂态仿真法验证了所提方法的有效性。最后,将所提方法与改进Prony算法、MCEEMD法在不同噪声水平和振荡频率下进行对比,结果表明,所提方法能够有效地抑制原始信号的噪声干扰,对耦合的次/超同步振荡信号分解更加准确,参数辨识结果可靠性较高,对风电系统振荡溯源、改善系统阻尼具有一定的参考意义。展开更多
Open and green spaces are essential elements of cities.With the COVID epidemic,the importance of the need for open and green spaces in urban areas has become more understood.The aim of this study is to create a new an...Open and green spaces are essential elements of cities.With the COVID epidemic,the importance of the need for open and green spaces in urban areas has become more understood.The aim of this study is to create a new and contemporary square in the working area where the current use and traffic create chaos,to add a new square to the open and green areas in Ankara(Turkey)and to create a connection between this area and the existing open and green areas.At the same time,health workers are honoured through a memorial area integrated into the square.The importance of the location chosen as the study area is that it is surrounded by many public health facilities and is a point of intersection of Ankara’s existing open green space systems.Throughout the three-stage design process,brainstorming sessions were held,drawings and sketches were made,and urban analyses were carried out on transport,culture,art,education,health,open and green spaces.Solutions were proposed for both indoor and outdoor spaces,and the forms were transformed into functional design elements and reflected in the space.As a result,after the pandemic,a city square has been created where people can socialise again,with a monument,a square,water surfaces,an amphitheatre,viewing terraces,a market area,a bridge,sitting and walking areas that are appropriate to the capital.展开更多
Recently,there have been few reports on the hot extrusion process of magnesium(Mg)alloy square tubes.In this work,we introduce a novel hot extrusion process called tube continuous expanding shear extrusion(t CESE)to p...Recently,there have been few reports on the hot extrusion process of magnesium(Mg)alloy square tubes.In this work,we introduce a novel hot extrusion process called tube continuous expanding shear extrusion(t CESE)to produce Mg alloy square tubes with heterogeneous structures.Compared to previously reported hot-extruded Mg alloy tubes,the tCESE samples exhibit simultaneous enhancements in both strength and ductility.The microstructure evolution during the t CESE process was analyzed in detail.It was found that the microstructure developed consecutively as a result of twinning-induced dynamic recrystallization(TDRX),discontinuous dynamic recrystallization(DDRX)and continuous dynamic recrystallization(CDRX)with different nucleation of new orientations,while static recrystallization(SRX)promoted the formation of heterogeneous structures.The strengthening mechanism in the t CESE samples was revealed by loading-unloading-reloading(LUR)tensile tests,viscoplastic self-consistent(VPSC)simulation and intermittent tensile tests.The improvement of the strength in the tCESE samples is attributed to the size refinement of the grains and the second-phases,and more importantly,to hetero-deformation induced(HDI)strengthening.The improvement of the ductility in the t CESE samples can be attributed to the significant increase in non-basal dislocations within the heterogeneous structures during tensile deformation.展开更多
基金support from the Fundamental Research Funds for the Central Universities(2022CDJQY-005,2024CDJXY010)the Guangxi Science and Technology Program(AB24010229)is greatly acknowledged.
文摘In manganese electrolysis,electrochemical oscillations and manganese dendrite growth are typical nonlinear phenomena critical for energy consumption reduction.Nonetheless,existing research lacks a deep understanding of their underlying mechanisms.In this study,we systematically explored the evolution of anode electrochemical oscillations during manganese electrolysis and designed a square wave circuit to effectively suppress oscillations and dendrite growth while reducing energy consumption.A novel four-dimensional differential equation was introduced to explore the internal dynamic mechanisms of typical nonlinear behaviors.The experimental results showed that while the evolutionary patterns of current and potential oscillation signals were consistent,their waveform directions were opposite.The square wave current effectively suppressed both electrochemical oscillations and the growth of manganese dendrites.Furthermore,compared to direct current electrolysis,the square wave current improved the current efficiency by 3.6%and reduced the energy consumption by 0.32 kW·h·kg^(−1).
基金Fundamental Research Funds for the Central Universities under Grant 3072025YC0802the National Natural Science Foundation of China under Grant 62001138Heilongjiang Provincial Natural Science Foundation of China under Grant LH2021F009。
文摘Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively high row weights,the existing blind recognition algorithms based on a candidate set generally perform worse.In this paper,we propose a blind recognition method for LDPC codes,called as tangent function assisted least square(TLS)method,which improves recognition performances by constructing a new cost function.To characterize the constraint degree among received vectors and paritycheck vectors,a feature function based on tangent function is constructed in the proposed algorithm.A cost function based on least square method is also established according to the feature function values satisfying the parity-check relationship.Moreover,the minimum average value in TLS is obtained on the candidate set.Numerical analysis and simulation results show that recognition performances of TLS algorithm are consistent with theoretical results.Compared with existing algorithms,the proposed method possesses better recognition performances.
基金supported in part by the National Natural Science Foundation of China(62573387)the Natural Science Foundation of Zhejiang province,China(LY24F030004)the Fundamental Research Funds of Zhejiang Sci-Tech University(25222139-Y).
文摘Partial least squares (PLS) model maximizes the covariance between process variables and quality variables,making it widely used in quality-related fault detection.However,traditional PLS methods focus primarily on linear processes,leading to poor performance in dynamic nonlinear processes.In this paper,a novel quality-related fault detection method,named DiCAE-PLS,is developed by combining dynamic-inner convolutional autoencoder with PLS.In the proposed DiCAE-PLS method,latent features are first extracted through dynamic-inner convolutional autoencoder (DiCAE) to capture process dynamics and nonlinearity from process variables.Then,a PLS model is established to build the relationship between the extracted latent features and the final product quality.To detect quality-related faults,Hotelling's T^(2) statistic is employed.The developed quality-related fault detection is applied to the widely used industrial benchmark of the Tennessee.
基金support from the National Natural Science Foundation of China(Grant Nos.42177142 and 52378477)the Key Research and Development Program of Shaanxi(Grant No.2023-YBSF-486).
文摘The identification of rock mass hazard sources is fundamental for preventing rockfall and landslide disasters in mountainous regions,with rock mass structural characteristics playing a vital role in hazard assessment.In this study,terrestrial laser scanning(TLS)and unmanned aerial vehicle(UAV)technologies were integrated to enhance the evaluation methodology for rock mass hazard sources,focusing on the Sichuan Yanjiang Expressway project in China.The findings demonstrate that TLS-UAV technology enhanced both spatial coverage and data density in slope modeling.Through integrated algorithmic analysis,rock discontinuities within heterogeneous datasets were systematically identified,enabling quantitative extraction and statistical analysis of key geometric parameters,including orientation,trace length,spacing,and roughness.Furthermore,quantitative models were developed for cohesion,friction angle and the morphology parameter M of in situ discontinuities,respectively,facilitating efficient mechanical parameter acquisition.A novel rock mass hazard index(RHI)was developed incorporating discontinuity geometric rating(DGR),discontinuity mechanical rating(DMR),and slope mass rating(SMR).Field validation confirmed the methodology's effectiveness in evaluating risk levels and spatial heterogeneity of rock mass hazard sources,revealing the contribution of different discontinuity sets to the rock mass hazard and identifying the primary discontinuity sets controlling instability mechanisms.This study is of great significance for evaluating discontinuity-controlled rock mass hazard sources and preventing rockfall disasters.
文摘针对实际点云数据中存在的噪点与缺陷对拟合平面时带来的影响,提出一种基于最小平方中值算法(least median of squares,LMedS)与距离加权总体最小二乘法(weighted total least squares based on distance,WTLSD)相结合的平面拟合算法。通过最小平方中值算法初步去除点云中的噪点,并基于距离构建初始权重矩阵,利用距离加权总体最小二乘法对点云进行平面拟合,减少平面中凸起与凹陷等缺陷对平面拟合的影响,该算法与传统平面拟合算法相比具备消除异常点与平面缺陷的优点,具备更高的拟合精度;与随机采样一致性算法(random sample consensus,RANSAC)相比具有更高的拟合效率与相近的拟合精度。
文摘为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决定分解模态数和带宽,结合最小二乘-旋转不变技术(total least square-estimating signal parameter via rotational invariance techniques,TLS-ESPRIT)对分解出的振荡分量进行参数辨识,无需另外使用降噪算法。通过复合信号测试法、PSCAD/EMTDC电磁暂态仿真法验证了所提方法的有效性。最后,将所提方法与改进Prony算法、MCEEMD法在不同噪声水平和振荡频率下进行对比,结果表明,所提方法能够有效地抑制原始信号的噪声干扰,对耦合的次/超同步振荡信号分解更加准确,参数辨识结果可靠性较高,对风电系统振荡溯源、改善系统阻尼具有一定的参考意义。
文摘Open and green spaces are essential elements of cities.With the COVID epidemic,the importance of the need for open and green spaces in urban areas has become more understood.The aim of this study is to create a new and contemporary square in the working area where the current use and traffic create chaos,to add a new square to the open and green areas in Ankara(Turkey)and to create a connection between this area and the existing open and green areas.At the same time,health workers are honoured through a memorial area integrated into the square.The importance of the location chosen as the study area is that it is surrounded by many public health facilities and is a point of intersection of Ankara’s existing open green space systems.Throughout the three-stage design process,brainstorming sessions were held,drawings and sketches were made,and urban analyses were carried out on transport,culture,art,education,health,open and green spaces.Solutions were proposed for both indoor and outdoor spaces,and the forms were transformed into functional design elements and reflected in the space.As a result,after the pandemic,a city square has been created where people can socialise again,with a monument,a square,water surfaces,an amphitheatre,viewing terraces,a market area,a bridge,sitting and walking areas that are appropriate to the capital.
基金the National Science Foundation of China(52071042)Chongqing Talent Plan(CQYC202003047)+1 种基金the Chongqing Natural Science Foundation Project of CSTB2021YCJH-BGZXM0148 and CSTB2023NSCQ-MSX0079the Open Fund of the National Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle,Hunan University(Grant No.82315001)。
文摘Recently,there have been few reports on the hot extrusion process of magnesium(Mg)alloy square tubes.In this work,we introduce a novel hot extrusion process called tube continuous expanding shear extrusion(t CESE)to produce Mg alloy square tubes with heterogeneous structures.Compared to previously reported hot-extruded Mg alloy tubes,the tCESE samples exhibit simultaneous enhancements in both strength and ductility.The microstructure evolution during the t CESE process was analyzed in detail.It was found that the microstructure developed consecutively as a result of twinning-induced dynamic recrystallization(TDRX),discontinuous dynamic recrystallization(DDRX)and continuous dynamic recrystallization(CDRX)with different nucleation of new orientations,while static recrystallization(SRX)promoted the formation of heterogeneous structures.The strengthening mechanism in the t CESE samples was revealed by loading-unloading-reloading(LUR)tensile tests,viscoplastic self-consistent(VPSC)simulation and intermittent tensile tests.The improvement of the strength in the tCESE samples is attributed to the size refinement of the grains and the second-phases,and more importantly,to hetero-deformation induced(HDI)strengthening.The improvement of the ductility in the t CESE samples can be attributed to the significant increase in non-basal dislocations within the heterogeneous structures during tensile deformation.
