In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and pro...In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.展开更多
In recent years,it is the general trend to adopt the standards of international engineering education certification to construct curriculum.“Software Process and Tools”is one of the core courses of Harbin Institute ...In recent years,it is the general trend to adopt the standards of international engineering education certification to construct curriculum.“Software Process and Tools”is one of the core courses of Harbin Institute of Technology’s software engineering undergraduate training program.Focusing on the construction work and practical exploration of the course in the process of reforming the software engineering professional curriculum system,and how to achieve the standards of engineering education certification,This paper makes a review and summary.This paper focuses on the status and the role of the course in the whole curriculum system,as well as project-driven teaching content design and practical teaching methods.And summarizes the experience and results of 3 rounds of teaching practice.展开更多
An investigation has been carried out to compare th e cutting performance and tool life evaluation of high speed steel broach samp les. The comparison has been done between conventional M2 and Anti-Segregation Process...An investigation has been carried out to compare th e cutting performance and tool life evaluation of high speed steel broach samp les. The comparison has been done between conventional M2 and Anti-Segregation Process (ASP) ASP53 and ASP30 high speed steel broach samples. The ASP53 was a development material. The cutting performance was evaluated by measuring the c utting forces and calculating the specific cutting energy, an indicator of cutti ng performance. As the roughness of the machined surface is an important criter ion in the evaluation of performance of a tool, the surface roughness of the workpiece was studied as a function of undeformed chip thickness. The workpiec e material was 150M36 alloy steel used in manufacture of automobile engines. Th e performance tests were conducted at two cutting speeds, which were 0 7 m/min and 10.5 m/min respectively. This allowed a better understanding of the effect of cutting speed on tool performance. The wear tests were performed at a cuttin g speed on 10.5 m/min. The cutting edges of ASP broach samples were finer compared to that of M2. Ther e was no practical difference in the cutting forces and the specific cutting ene rgy while cutting with MS, ASP30 and ASP53 broach samples. The ASP30 and ASP53 tools have a better surface roughness on the machined surface than that of M2 at both cutting speeds. The ASP30 gave 2.25 times the life and an improved surfac e finish compared to M2 steel. The ASP53 gave 1.3 times the life of M2 steel. These results should prove useful to the tool designer and manufacturing enginee r.展开更多
There is an urgent necessity to introduce the life cycle development method and a Computer-Aided Software Engineering (CASE) environment to support the development of a Computer Integrated Manufacturing (CIM) system. ...There is an urgent necessity to introduce the life cycle development method and a Computer-Aided Software Engineering (CASE) environment to support the development of a Computer Integrated Manufacturing (CIM) system. In this paper, we present several ideas while inquiring how to apply CASE tools to CIM process effectively, and propose five proper applicable paradigms to enhance the possibility of applications that the CIM process may make better use of CASE tools.展开更多
Disodium 5′-ribonucleotide,which is composed of disodium 5′-inosine(IMP)and disodium 5′-guanosine(GMP),is an important food additive.The lack of kinetic studies of it causes a lack of clarity in understanding the c...Disodium 5′-ribonucleotide,which is composed of disodium 5′-inosine(IMP)and disodium 5′-guanosine(GMP),is an important food additive.The lack of kinetic studies of it causes a lack of clarity in understanding the complicated multi-solute crystallization of IMP+GMP in ethanol-water.In this work,process analytical technology tools were used to obtain the thermodynamics and kinetic data from the experiments,the kinetic parameters of anti-solvent and cooling crystallization were investigated.The crystal form of IMP+GMP mixed crystal was determined,which was consistent with the IMP whether crystallized from pure water or ethanol-water.The effects of different anti-solvent addition rates and cooling rates on the metastable zone widths were studied,and the opposite effect on metastable zone width was found.The modified exponential empirical function was developed to correlate nucleation and growth kinetic equations under different conditions.The kinetic data were well fitted with adjusted correlation coefficient(adj-R^(2)>0.7),which is sufficient to provide a valid reference for process design and control.展开更多
Background： In eukaryotic genome, chromatin is not randomly distributed in cell nuclei, but instead is organized into higher-order structures. Emerging evidence indicates that these higher-order chromatin structures ...Background： In eukaryotic genome, chromatin is not randomly distributed in cell nuclei, but instead is organized into higher-order structures. Emerging evidence indicates that these higher-order chromatin structures play important roles in regulating genome functions such as transcription and DNA replication. With the advancement in 3C （chromosome conformation capture） based technologies, Hi-C has been widely used to investigate genome-wide long- range chromatin interactions during cellular differentiation and oncogenesis. Since the first publication of Hi-C assay in 2009, lots of bioinformatic tools have been implemented for processing Hi-C data from mapping raw reads to normalizing contact matrix and high interpretation, either providing a whole workflow pipeline or focusing on a particular process. Results： This article reviews the general Hi-C data processing workflow and the currently popular Hi-C data processing tools. We highlight on how these tools are used for a full interpretation of Hi-C results. Conclusions： Hi-C assay is a powerful tool to investigate the higher-order chromatin structure. Continued development of novel methods for Hi-C data analysis will be necessary for better understanding the regulatory function of genome organization.展开更多
Based on the principle of Statistical Energy Analysis (SEA) for non-conservatively coupled systems under general excitations, relationship between noise radiated from and excitations on coupled complex structures is s...Based on the principle of Statistical Energy Analysis (SEA) for non-conservatively coupled systems under general excitations, relationship between noise radiated from and excitations on coupled complex structures is studied, which lays a foundation for the determination of noise/vibration energy by evaluation of exciting forces, and from that the quantitative analysis of the effects of an excitation on sound power from a sub-structure can be done. With extending of the relationship to the study of cutting noise, regression analysis method for evaluating the effects of cutting process on machine tool noise is established. Results show that cutting process has generally negligible effects on machine tool noise, and there is no apparent difference between machine tool noise in cutting condition and in idle one.展开更多
文摘In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.
文摘In recent years,it is the general trend to adopt the standards of international engineering education certification to construct curriculum.“Software Process and Tools”is one of the core courses of Harbin Institute of Technology’s software engineering undergraduate training program.Focusing on the construction work and practical exploration of the course in the process of reforming the software engineering professional curriculum system,and how to achieve the standards of engineering education certification,This paper makes a review and summary.This paper focuses on the status and the role of the course in the whole curriculum system,as well as project-driven teaching content design and practical teaching methods.And summarizes the experience and results of 3 rounds of teaching practice.
文摘An investigation has been carried out to compare th e cutting performance and tool life evaluation of high speed steel broach samp les. The comparison has been done between conventional M2 and Anti-Segregation Process (ASP) ASP53 and ASP30 high speed steel broach samples. The ASP53 was a development material. The cutting performance was evaluated by measuring the c utting forces and calculating the specific cutting energy, an indicator of cutti ng performance. As the roughness of the machined surface is an important criter ion in the evaluation of performance of a tool, the surface roughness of the workpiece was studied as a function of undeformed chip thickness. The workpiec e material was 150M36 alloy steel used in manufacture of automobile engines. Th e performance tests were conducted at two cutting speeds, which were 0 7 m/min and 10.5 m/min respectively. This allowed a better understanding of the effect of cutting speed on tool performance. The wear tests were performed at a cuttin g speed on 10.5 m/min. The cutting edges of ASP broach samples were finer compared to that of M2. Ther e was no practical difference in the cutting forces and the specific cutting ene rgy while cutting with MS, ASP30 and ASP53 broach samples. The ASP30 and ASP53 tools have a better surface roughness on the machined surface than that of M2 at both cutting speeds. The ASP30 gave 2.25 times the life and an improved surfac e finish compared to M2 steel. The ASP53 gave 1.3 times the life of M2 steel. These results should prove useful to the tool designer and manufacturing enginee r.
文摘There is an urgent necessity to introduce the life cycle development method and a Computer-Aided Software Engineering (CASE) environment to support the development of a Computer Integrated Manufacturing (CIM) system. In this paper, we present several ideas while inquiring how to apply CASE tools to CIM process effectively, and propose five proper applicable paradigms to enhance the possibility of applications that the CIM process may make better use of CASE tools.
基金Financial supports from the National Natural Science Foundation of China (Nos.22178121 and 21908254)are greatly appreciated.
文摘Disodium 5′-ribonucleotide,which is composed of disodium 5′-inosine(IMP)and disodium 5′-guanosine(GMP),is an important food additive.The lack of kinetic studies of it causes a lack of clarity in understanding the complicated multi-solute crystallization of IMP+GMP in ethanol-water.In this work,process analytical technology tools were used to obtain the thermodynamics and kinetic data from the experiments,the kinetic parameters of anti-solvent and cooling crystallization were investigated.The crystal form of IMP+GMP mixed crystal was determined,which was consistent with the IMP whether crystallized from pure water or ethanol-water.The effects of different anti-solvent addition rates and cooling rates on the metastable zone widths were studied,and the opposite effect on metastable zone width was found.The modified exponential empirical function was developed to correlate nucleation and growth kinetic equations under different conditions.The kinetic data were well fitted with adjusted correlation coefficient(adj-R^(2)>0.7),which is sufficient to provide a valid reference for process design and control.
基金This work is supported by the National Basic Research Program of China （Nos. 2016YFA0100703 and 2015CB964800） and the National Natural Science Foundation of China （No. 31271354）.
文摘Background： In eukaryotic genome, chromatin is not randomly distributed in cell nuclei, but instead is organized into higher-order structures. Emerging evidence indicates that these higher-order chromatin structures play important roles in regulating genome functions such as transcription and DNA replication. With the advancement in 3C （chromosome conformation capture） based technologies, Hi-C has been widely used to investigate genome-wide long- range chromatin interactions during cellular differentiation and oncogenesis. Since the first publication of Hi-C assay in 2009, lots of bioinformatic tools have been implemented for processing Hi-C data from mapping raw reads to normalizing contact matrix and high interpretation, either providing a whole workflow pipeline or focusing on a particular process. Results： This article reviews the general Hi-C data processing workflow and the currently popular Hi-C data processing tools. We highlight on how these tools are used for a full interpretation of Hi-C results. Conclusions： Hi-C assay is a powerful tool to investigate the higher-order chromatin structure. Continued development of novel methods for Hi-C data analysis will be necessary for better understanding the regulatory function of genome organization.
文摘Based on the principle of Statistical Energy Analysis (SEA) for non-conservatively coupled systems under general excitations, relationship between noise radiated from and excitations on coupled complex structures is studied, which lays a foundation for the determination of noise/vibration energy by evaluation of exciting forces, and from that the quantitative analysis of the effects of an excitation on sound power from a sub-structure can be done. With extending of the relationship to the study of cutting noise, regression analysis method for evaluating the effects of cutting process on machine tool noise is established. Results show that cutting process has generally negligible effects on machine tool noise, and there is no apparent difference between machine tool noise in cutting condition and in idle one.
