Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technologi...Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technological revolution and industrial transformation to higher education,cultivating top-notch innovative intellectuals with comprehensive engineering qualities,meeting the requirements of being able to solve complex engineering problems rather than just cognitive capabilities,forming two core courses through reconstructing and reshaping the core courses of the major.The core courses include Drive,Measurement,and Control I and Drive,Measurement,and Control II,which highlight the comprehensive framework of mechanical and electronic engineering professional knowledge,continuing the comprehensive practical course system based on the unity of knowledge and practice,following the trend of new engineering,highlighting the practicality of professional innovation,assisting engineering education reform,and promoting high-quality development of new engineering professionals cultivation.展开更多
Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the...Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.展开更多
Knowledge graph technology play a more and more important role in various fields of industry and academia.This paper firstly introduces the general framework of the knowledge graph construction,which includes three st...Knowledge graph technology play a more and more important role in various fields of industry and academia.This paper firstly introduces the general framework of the knowledge graph construction,which includes three stages:information extraction,knowledge fusion and knowledge processing.In order to improve the efficiency of quality and safety supervision of transportation engineering construction,this paper constructs a knowledge graph by acquiring multi-sources heterogeneous data from supervision of transportation engineering quality and safety.It employs a bottom-up construction strategy and some natural language processing methods to solve the problems of the knowledge extraction for transportation engineering construction.We use the entity relation extraction method to extract the entity triples from the multi-sources heterogeneous data,and then employ knowledge inference to complete the edges in the constructed knowledge graph,finally perform quality evaluation to add the valid triples to the knowledge graph for updating.Subgraph matching technology is also exploited to retrieve the constructed knowledge graph for efficiently acquiring the useful knowledge about the quality and safety of transportation engineering projects.The results show that the constructed knowledge graph provides a practical and valuable tool for the quality and safety supervision of transportation engineering construction.展开更多
The quality of the software product is a crucial factor that contributes to its success. Therefore, it is important to specify the right software quality requirements that will establish the basis for desired quality ...The quality of the software product is a crucial factor that contributes to its success. Therefore, it is important to specify the right software quality requirements that will establish the basis for desired quality of the final system/software product. There are several known methodologies/ processes that support the specification of the system/software functional requirements starting from the user needs to finally obtain the system requirements that the developers can implement through their development process. System/software quality requirements are interdependent with functional requirements, which means that the system/software quality requirements are meant to be specified in parallel with the latter. The ISO/IEC 25000 [1] SQuaRE series of standards include the standard ISO/IEC 25030—Software engineering—Software Quality Requirements and Evaluation—Quality requirements [2], which has as main goal to help specify software quality requirements. As to date, this standard does not offer clear and concise steps that a software quality engineer could follow in order to specify them. This article presents modifications recommended for ISO/IEC 25030 standard, with, among the others, a new requirements definition process that allows for specifying the system/software quality requirements taking into account the existing published system and software quality model ISO/IEC 25010 [3] as well as all the stake- holders of the project.展开更多
The relationship between major quality tools such as quality function development (QFD), failure mode and effects analysis (FMEA), design of experiments (DOE) and statistical process control (SPC) is analyzed ...The relationship between major quality tools such as quality function development (QFD), failure mode and effects analysis (FMEA), design of experiments (DOE) and statistical process control (SPC) is analyzed through an extensive review of the literature and the concurrent quality engineering philosophy, and a basic structure for the integration of quality tools is presented. An integrated quality management system (IQMS) is developed using C++ Builder, running in the Windows 2000 Server environment with the basic internet connections, and SQL Server 2000 as the platform for developing the database, An illustrative example applying IQMS to the continuous quality improvement for a crane equipment manufacturing is reported. The result shows that the application of IQMS can optimize the process of design and manufacturing, shorten the cycle time of product, reduce the cost, and realize quality improvement continuously, The proposed integrated framework with IOMS is believed to be applicable to continuous quality improvement in many manufacturing companies.展开更多
This paper presents a method which uses a random model and adopts the Monte Carlo simulation method to analyze the randomness of the actual balan...This paper presents a method which uses a random model and adopts the Monte Carlo simulation method to analyze the randomness of the actual balancing quality of a multi cylinder engine.The uncertainties considered in the analysis are the reciprocating mass,rotating mass,connecting rod length,crank radius and crank phase angle of individual crank mechanisms.According to the calculated results with respect to inertia forces and couples,the regularities of probabilistic balancing quality are discussed in detail,and some views are offered.展开更多
To illuminate the spatio-temporal variation characteristics and geochemical driving mechanism of soil pH in the Nenjiang River Basin,the National Multi-objective Regional Geochemical Survey data of topsoil,the Second ...To illuminate the spatio-temporal variation characteristics and geochemical driving mechanism of soil pH in the Nenjiang River Basin,the National Multi-objective Regional Geochemical Survey data of topsoil,the Second National Soil Survey data and Normalized Difference Vegetation Index(NDVI)were analyzed.The areas of neutral and alkaline soil decreased by 21100 km^(2)and 30500 km^(2),respectively,while that of strongly alkaline,extremely alkaline,and strongly acidic soil increased by 19600 km^(2),18200 km^(2),and 15500 km^(2),respectively,during the past 30 years.NDVI decreased with the increase of soil pH when soil pH>8.0,and it was reversed when soil pH<5.0.There were significant differences in soil pH with various surface cover types,which showed an ascending order:Arbor<reed<maize<rice<high and medium-covered meadow<low-covered meadow<Puccinellia.The weathering products of minerals rich in K_(2)O,Na_(2)O,CaO,and MgO entered into the low plain and were enriched in different parts by water transportation and lake deposition,while Fe and Al remained in the low hilly areas,which was the geochemical driving mechanism.The results of this study will provide scientific basis for making scientific and rational decisions on soil acidification and salinization.展开更多
There are more researches on engine fan noise control focusing on reducing fan noise level through optimizing fan structure,and a lot of research achievements have been obtained.However,researches on the effect of fan...There are more researches on engine fan noise control focusing on reducing fan noise level through optimizing fan structure,and a lot of research achievements have been obtained.However,researches on the effect of fan noise to engine noise quality are lacking.The influences of the effects of fan structure optimization on the engine noise quality are unclear.Thus,there will be a decline in fan noise level,but the deterioration of engine noise quality.Aiming at the above problems,in consideration of fan structure design and engine noise quality,an innovative method to analyze the contribution of fan noise to engine noise quality using psychoacoustic theory is proposed.The noises of diesel engine installing different cooling fans are measured by using the acoustic pressure method.The experiment results are regarded as analysis samples.The model of sensory pleasantness is used to analyze the sound quality of a diesel engine with different cooling fans.Results show that after installing 10-blade fan in medium diameter the sensory pleasantness at each test point is increased,and the increase is 13.53% on average,which indicate the improvement of the engine noise quality.In order to verify the psychoacoustical analysis,the subjective assessment is carried out.The test result shows the noise quality of engine installed10-blade fan in medium diameter is most superior.1/3 octave frequency spectrum analysis is used to study the reason of the improvement of engine noise quality.It is found that after installing proper cooling fan the sound pressure level below 400 Hz are obviously increased,the frequency assignment and spectral envelope are more reasonable and a proper cooling fan can optimize the spectrum structure of the engine noise.The psychoacoustic study is applied in the contribution of fan noise to engine noise,and the idea of engine sound quality improvement through the structure optimization is proposed.展开更多
Large-scale object-oriented(OO) software systems have recently been found to share global network characteristics such as small world and scale free,which go beyond the scope of traditional software measurement and ...Large-scale object-oriented(OO) software systems have recently been found to share global network characteristics such as small world and scale free,which go beyond the scope of traditional software measurement and assessment methodologies.To measure the complexity at various levels of granularity,namely graph,class(and object) and source code,we propose a hierarchical set of metrics in terms of coupling and cohesion-the most important characteristics of software,and analyze a sample of 12 open-source OO software systems to empirically validate the set.Experimental results of the correlations between cross-level metrics indicate that the graph measures of our set complement traditional software metrics well from the viewpoint of network thinking,and provide more effective information about fault-prone classes in practice.展开更多
文摘Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technological revolution and industrial transformation to higher education,cultivating top-notch innovative intellectuals with comprehensive engineering qualities,meeting the requirements of being able to solve complex engineering problems rather than just cognitive capabilities,forming two core courses through reconstructing and reshaping the core courses of the major.The core courses include Drive,Measurement,and Control I and Drive,Measurement,and Control II,which highlight the comprehensive framework of mechanical and electronic engineering professional knowledge,continuing the comprehensive practical course system based on the unity of knowledge and practice,following the trend of new engineering,highlighting the practicality of professional innovation,assisting engineering education reform,and promoting high-quality development of new engineering professionals cultivation.
文摘Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.
基金This work was supported by Scientific Research Project of Department of Transportation of Hunan Province under Grant No.201814.
文摘Knowledge graph technology play a more and more important role in various fields of industry and academia.This paper firstly introduces the general framework of the knowledge graph construction,which includes three stages:information extraction,knowledge fusion and knowledge processing.In order to improve the efficiency of quality and safety supervision of transportation engineering construction,this paper constructs a knowledge graph by acquiring multi-sources heterogeneous data from supervision of transportation engineering quality and safety.It employs a bottom-up construction strategy and some natural language processing methods to solve the problems of the knowledge extraction for transportation engineering construction.We use the entity relation extraction method to extract the entity triples from the multi-sources heterogeneous data,and then employ knowledge inference to complete the edges in the constructed knowledge graph,finally perform quality evaluation to add the valid triples to the knowledge graph for updating.Subgraph matching technology is also exploited to retrieve the constructed knowledge graph for efficiently acquiring the useful knowledge about the quality and safety of transportation engineering projects.The results show that the constructed knowledge graph provides a practical and valuable tool for the quality and safety supervision of transportation engineering construction.
文摘The quality of the software product is a crucial factor that contributes to its success. Therefore, it is important to specify the right software quality requirements that will establish the basis for desired quality of the final system/software product. There are several known methodologies/ processes that support the specification of the system/software functional requirements starting from the user needs to finally obtain the system requirements that the developers can implement through their development process. System/software quality requirements are interdependent with functional requirements, which means that the system/software quality requirements are meant to be specified in parallel with the latter. The ISO/IEC 25000 [1] SQuaRE series of standards include the standard ISO/IEC 25030—Software engineering—Software Quality Requirements and Evaluation—Quality requirements [2], which has as main goal to help specify software quality requirements. As to date, this standard does not offer clear and concise steps that a software quality engineer could follow in order to specify them. This article presents modifications recommended for ISO/IEC 25030 standard, with, among the others, a new requirements definition process that allows for specifying the system/software quality requirements taking into account the existing published system and software quality model ISO/IEC 25010 [3] as well as all the stake- holders of the project.
基金This project is supported by National Natural Science Foundation of China (No.70372062)Tianjin City Key Technologies R&D Program(No.04310881R)New Century Excellent Talent Program of Education Ministry of China(No.NCET-04-0240).
文摘The relationship between major quality tools such as quality function development (QFD), failure mode and effects analysis (FMEA), design of experiments (DOE) and statistical process control (SPC) is analyzed through an extensive review of the literature and the concurrent quality engineering philosophy, and a basic structure for the integration of quality tools is presented. An integrated quality management system (IQMS) is developed using C++ Builder, running in the Windows 2000 Server environment with the basic internet connections, and SQL Server 2000 as the platform for developing the database, An illustrative example applying IQMS to the continuous quality improvement for a crane equipment manufacturing is reported. The result shows that the application of IQMS can optimize the process of design and manufacturing, shorten the cycle time of product, reduce the cost, and realize quality improvement continuously, The proposed integrated framework with IOMS is believed to be applicable to continuous quality improvement in many manufacturing companies.
文摘This paper presents a method which uses a random model and adopts the Monte Carlo simulation method to analyze the randomness of the actual balancing quality of a multi cylinder engine.The uncertainties considered in the analysis are the reciprocating mass,rotating mass,connecting rod length,crank radius and crank phase angle of individual crank mechanisms.According to the calculated results with respect to inertia forces and couples,the regularities of probabilistic balancing quality are discussed in detail,and some views are offered.
基金supported by China Geological Survey(DD20230554,DD20230089)the Strategic Priority Research Program of the Chinese Academy of Science(XDA28020302)the funding project of Northeast Geological S&T Innovation Center of China Geological Survey(QCJJ2022-40).
文摘To illuminate the spatio-temporal variation characteristics and geochemical driving mechanism of soil pH in the Nenjiang River Basin,the National Multi-objective Regional Geochemical Survey data of topsoil,the Second National Soil Survey data and Normalized Difference Vegetation Index(NDVI)were analyzed.The areas of neutral and alkaline soil decreased by 21100 km^(2)and 30500 km^(2),respectively,while that of strongly alkaline,extremely alkaline,and strongly acidic soil increased by 19600 km^(2),18200 km^(2),and 15500 km^(2),respectively,during the past 30 years.NDVI decreased with the increase of soil pH when soil pH>8.0,and it was reversed when soil pH<5.0.There were significant differences in soil pH with various surface cover types,which showed an ascending order:Arbor<reed<maize<rice<high and medium-covered meadow<low-covered meadow<Puccinellia.The weathering products of minerals rich in K_(2)O,Na_(2)O,CaO,and MgO entered into the low plain and were enriched in different parts by water transportation and lake deposition,while Fe and Al remained in the low hilly areas,which was the geochemical driving mechanism.The results of this study will provide scientific basis for making scientific and rational decisions on soil acidification and salinization.
基金supported by National Natural Science Foundation of China (Grant No. 50975192)PhD Programs Foundation of Ministryof China(Grant No. 20090032110001)
文摘There are more researches on engine fan noise control focusing on reducing fan noise level through optimizing fan structure,and a lot of research achievements have been obtained.However,researches on the effect of fan noise to engine noise quality are lacking.The influences of the effects of fan structure optimization on the engine noise quality are unclear.Thus,there will be a decline in fan noise level,but the deterioration of engine noise quality.Aiming at the above problems,in consideration of fan structure design and engine noise quality,an innovative method to analyze the contribution of fan noise to engine noise quality using psychoacoustic theory is proposed.The noises of diesel engine installing different cooling fans are measured by using the acoustic pressure method.The experiment results are regarded as analysis samples.The model of sensory pleasantness is used to analyze the sound quality of a diesel engine with different cooling fans.Results show that after installing 10-blade fan in medium diameter the sensory pleasantness at each test point is increased,and the increase is 13.53% on average,which indicate the improvement of the engine noise quality.In order to verify the psychoacoustical analysis,the subjective assessment is carried out.The test result shows the noise quality of engine installed10-blade fan in medium diameter is most superior.1/3 octave frequency spectrum analysis is used to study the reason of the improvement of engine noise quality.It is found that after installing proper cooling fan the sound pressure level below 400 Hz are obviously increased,the frequency assignment and spectral envelope are more reasonable and a proper cooling fan can optimize the spectrum structure of the engine noise.The psychoacoustic study is applied in the contribution of fan noise to engine noise,and the idea of engine sound quality improvement through the structure optimization is proposed.
基金Supported by the National Grand Fundamental Research 973 Program of China under Grant No.2007CB310800the National Natural Science Foundation of China under Grant Nos.60873083 and 60803025+2 种基金the Research Fund for the Doctoral Program of Higher Education of China under Grant No.20090141120022the Natural Science Foundation of Hubei Province of China under Grant Nos.2008ABA379 and 2008CDB351the Fundamental Research Funds for the Central Universities of China under Grant No.6082005
文摘Large-scale object-oriented(OO) software systems have recently been found to share global network characteristics such as small world and scale free,which go beyond the scope of traditional software measurement and assessment methodologies.To measure the complexity at various levels of granularity,namely graph,class(and object) and source code,we propose a hierarchical set of metrics in terms of coupling and cohesion-the most important characteristics of software,and analyze a sample of 12 open-source OO software systems to empirically validate the set.Experimental results of the correlations between cross-level metrics indicate that the graph measures of our set complement traditional software metrics well from the viewpoint of network thinking,and provide more effective information about fault-prone classes in practice.