Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6020978
Chen Li, Dayong Li, D. Shi, B. Lu
In this paper, the basic principles of thermal analysis and the structure of thermal analysis device are briefly reviewed. The structure and properties of thermal analysis sample cup made of different materials and temperature sensor are summarized, and their advantages and disadvantages are indicated. Also, the thermocouple sample cup made of resin sand and thermocouple sample cup made of graphite are described in detail. Thermal analysis device is mainly composed of the sample cup and data acquisition and processing system, and the thermocouples are pre-embedded in the cup to monitor the temperature. The resin sand cup is widely used while it is disposable. Although the graphite sample cup and Cu sample cup can be reused, they can only be used in the thermal analysis of aluminum alloys.
{"title":"Current situation and development of thermal analysis technology and sample cup","authors":"Chen Li, Dayong Li, D. Shi, B. Lu","doi":"10.1109/IFOST.2011.6020978","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6020978","url":null,"abstract":"In this paper, the basic principles of thermal analysis and the structure of thermal analysis device are briefly reviewed. The structure and properties of thermal analysis sample cup made of different materials and temperature sensor are summarized, and their advantages and disadvantages are indicated. Also, the thermocouple sample cup made of resin sand and thermocouple sample cup made of graphite are described in detail. Thermal analysis device is mainly composed of the sample cup and data acquisition and processing system, and the thermocouples are pre-embedded in the cup to monitor the temperature. The resin sand cup is widely used while it is disposable. Although the graphite sample cup and Cu sample cup can be reused, they can only be used in the thermal analysis of aluminum alloys.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78289575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6020952
Hu Lan, Wei Wang, Yuanyuan Shangguan, Shangyang Lin
An experimental investigation on the cutting performance of fiber laser assisted oxygen cutting (Flaox) for 30 mm thick carbon steel plate was performed. The effects of laser power, cutting speed, assist gas pressure and focal point position on the quality characteristics of Flaox cut were discussed. It was shown that by reasonable selection of the process parameters, clean cut surface with little dross and the maximum cutting speed for acceptable cut quality were obtained. Visual examination indicated that there existed an optimum combination of laser power, cutting speed and the assist gas pressure, while focal point position had a major effect on the surface roughness. In addition, it is essential to initiate and sustain the exothermic reaction of iron and oxygen at cutting front as well as remove the melt. This can be achieved by selecting sufficient laser energy and ensuring a wider kerf.
{"title":"Fundamental studies on high power fiber laser cutting performance of 30 mm thick carbon steel plate","authors":"Hu Lan, Wei Wang, Yuanyuan Shangguan, Shangyang Lin","doi":"10.1109/IFOST.2011.6020952","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6020952","url":null,"abstract":"An experimental investigation on the cutting performance of fiber laser assisted oxygen cutting (Flaox) for 30 mm thick carbon steel plate was performed. The effects of laser power, cutting speed, assist gas pressure and focal point position on the quality characteristics of Flaox cut were discussed. It was shown that by reasonable selection of the process parameters, clean cut surface with little dross and the maximum cutting speed for acceptable cut quality were obtained. Visual examination indicated that there existed an optimum combination of laser power, cutting speed and the assist gas pressure, while focal point position had a major effect on the surface roughness. In addition, it is essential to initiate and sustain the exothermic reaction of iron and oxygen at cutting front as well as remove the melt. This can be achieved by selecting sufficient laser energy and ensuring a wider kerf.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85797995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021047
Liu Bo, Liang Wei, Sun Huilin, Li Jianxia
A frequency stabilization control system based on confocal F-P interferometer for semiconductor lasers is introduced to realize a stable frequency output. The system consists of the MCU MSP430, F-P confocal interferometer, current control and temperature control system. Giving an audio scanning voltage to the interferometer can make the laser power modulation. Then frequency offset can be got with the Lock-in Amplifier. Through the work of the servo system controls the working temperature and drive current of laser, frequency stability can be achieved. This method is not only simple in structure, but not band limit, and the frequency stabilization reaches 10−8.
{"title":"Design of frequency stabilization control system based on F-P cavity for semiconductor laser","authors":"Liu Bo, Liang Wei, Sun Huilin, Li Jianxia","doi":"10.1109/IFOST.2011.6021047","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021047","url":null,"abstract":"A frequency stabilization control system based on confocal F-P interferometer for semiconductor lasers is introduced to realize a stable frequency output. The system consists of the MCU MSP430, F-P confocal interferometer, current control and temperature control system. Giving an audio scanning voltage to the interferometer can make the laser power modulation. Then frequency offset can be got with the Lock-in Amplifier. Through the work of the servo system controls the working temperature and drive current of laser, frequency stability can be achieved. This method is not only simple in structure, but not band limit, and the frequency stabilization reaches 10−8.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88154884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021237
Jie Liu, Hong Zhao, Peng Wang, Liang Jiang, Chao Huang
A demodulation system for fiber Bragg grating (FBG) is designed based on distributed feedback (DFB) laser. By use of adjusting the internal temperature, wavelength tunable lasers is achieved, and utilizing the laser to realize the demodulation of FBG sensing signal. The system uses all-fiber structure, with fast response and high precision demodulation. experimental results show that the method is accurate and stable to realize the demodulation of FBG sensing signal, the system minimum resolution can achieve 1pm, the dynamic range was up to 3nm.
{"title":"FBG demodulation method based on DFB laser","authors":"Jie Liu, Hong Zhao, Peng Wang, Liang Jiang, Chao Huang","doi":"10.1109/IFOST.2011.6021237","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021237","url":null,"abstract":"A demodulation system for fiber Bragg grating (FBG) is designed based on distributed feedback (DFB) laser. By use of adjusting the internal temperature, wavelength tunable lasers is achieved, and utilizing the laser to realize the demodulation of FBG sensing signal. The system uses all-fiber structure, with fast response and high precision demodulation. experimental results show that the method is accurate and stable to realize the demodulation of FBG sensing signal, the system minimum resolution can achieve 1pm, the dynamic range was up to 3nm.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88466034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021131
J. Gai, Ziquan Tong, Shuang Cheng, Junjie Wang, Xu Liu
Wideband analog signals push contemporary analog- to-digital conversion systems to their performance limits. The recent development of compressive sensing theory enables direct analog-to-information conversion of sparse (or compressible) signals at sub-Nyquist rate. In this paper, we implement spectrum-sparse signals sub-Nyquist sampling by use of Modulated Wide Converter (MWC). To overcome the drawback of requiring exact sparsity of the existing recovery algorithm, we introduce the Sparsity Adaptive Matching Pursuit (SAMP) method into reconstruction stage to search the support set of unknown signal vectors blindly. The numerical experiments demonstrate that the MWC system with the proposed recovery algorithm can implement spectrum-sparse signals sub-Nyqiust sampling and perfect reconstruction under the condition of not knowing exact sparsity.
{"title":"A blind recovery algorithm for spectrum-sparse signals sub-Nyquist sampling","authors":"J. Gai, Ziquan Tong, Shuang Cheng, Junjie Wang, Xu Liu","doi":"10.1109/IFOST.2011.6021131","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021131","url":null,"abstract":"Wideband analog signals push contemporary analog- to-digital conversion systems to their performance limits. The recent development of compressive sensing theory enables direct analog-to-information conversion of sparse (or compressible) signals at sub-Nyquist rate. In this paper, we implement spectrum-sparse signals sub-Nyquist sampling by use of Modulated Wide Converter (MWC). To overcome the drawback of requiring exact sparsity of the existing recovery algorithm, we introduce the Sparsity Adaptive Matching Pursuit (SAMP) method into reconstruction stage to search the support set of unknown signal vectors blindly. The numerical experiments demonstrate that the MWC system with the proposed recovery algorithm can implement spectrum-sparse signals sub-Nyqiust sampling and perfect reconstruction under the condition of not knowing exact sparsity.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87060271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021013
Meilan Zhou, Hao Zhang, Zhaoming Gao
Aiming at the hybrid electric vehicle (HEV) low-emission and fuel-efficient advantages, the original model vehicle is refit into parallel hybrid electric vehicle (PHEV), and its power system parameters are designed. The dynamic performance, fuel economy and battery state of charge (SOC) on the NEDC typical driving cycle are simulated by hybrid electric vehicle simulation software ADVISOR. The comparisons between the simulation results of two models show that the modified HEV is better than the original model on fuel economy, the dynamic performance is basically unchanged, and the charge-discharge characteristics of battery achieve a balance on driving cycle, so the design of power system parameters is reasonable.
{"title":"Parameters optimization and performance simulation for parallel hybrid electric vehicle","authors":"Meilan Zhou, Hao Zhang, Zhaoming Gao","doi":"10.1109/IFOST.2011.6021013","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021013","url":null,"abstract":"Aiming at the hybrid electric vehicle (HEV) low-emission and fuel-efficient advantages, the original model vehicle is refit into parallel hybrid electric vehicle (PHEV), and its power system parameters are designed. The dynamic performance, fuel economy and battery state of charge (SOC) on the NEDC typical driving cycle are simulated by hybrid electric vehicle simulation software ADVISOR. The comparisons between the simulation results of two models show that the modified HEV is better than the original model on fuel economy, the dynamic performance is basically unchanged, and the charge-discharge characteristics of battery achieve a balance on driving cycle, so the design of power system parameters is reasonable.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84835254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021122
Shi-gang Wang, Junfeng Wu, L. Fan
The welding process is usually regarded as an uncertain sampled-data system. In this paper, the problem of resilient control for a class of uncertain sampled-data system is investigated, then pole contraints theory and the linear matrix inequality approach are incorporated to design resilient controller against possible perturbation, which results in sampled-data system is D-stable, moreover, the existence condition and the design approach of resilient controller are derived. Finally, simulation examples are presented to illustrate the effectiveness of the proposed algorithm.
{"title":"Application research for resilient control of the welding process systems with pole constraints","authors":"Shi-gang Wang, Junfeng Wu, L. Fan","doi":"10.1109/IFOST.2011.6021122","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021122","url":null,"abstract":"The welding process is usually regarded as an uncertain sampled-data system. In this paper, the problem of resilient control for a class of uncertain sampled-data system is investigated, then pole contraints theory and the linear matrix inequality approach are incorporated to design resilient controller against possible perturbation, which results in sampled-data system is D-stable, moreover, the existence condition and the design approach of resilient controller are derived. Finally, simulation examples are presented to illustrate the effectiveness of the proposed algorithm.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82910747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021120
S. mai, V. Vu, Myeongjae Yi
Classic OPC, released by OPC Foundation, is well accepted and applied in industrial automation, which led to many OPC products on the market from a variety of companies. However, OPC technology was based on retiring Microsoft COM/DCOM. The OPC Unified Architecture was introduced as the new generation specification with the main goal of keeping all the functionality of Classic OPC and switching from COM/DCOM technology to state -of-the-art web services. The OPC Foundation has been also developing OPC UA Toolkit that provide a collection of libraries, classes, and interfaces which make developers and programmers easy to create and implement OPC UA components. However, this toolkit is insufficient for developers and programmers to implement real monitoring and control applications from industry due to the limitations of such a toolkit, the complexity of related decision tasks and information systems, etc. In this paper, an OPC UA (Unified Architecture) client framework is proposed and developed by using OPC UA specifications, Service Oriented Architecture (SOA), web services, XML, OPC UA SDK, etc. This framework minimizes the efforts of developers and programmers in learning new techniques and allows system arc hitects and designers to perform dependency analysis on the development of monitoring and control applications. The initial results from the system implemented by Visual Studio 2008 are also provided.
由OPC基金会发布的经典OPC在工业自动化领域得到了广泛的认可和应用，这使得市场上出现了许多来自各种公司的OPC产品。然而，OPC技术是基于退役的Microsoft COM/DCOM。OPC统一架构是作为新一代规范引入的，其主要目标是保持经典OPC的所有功能，并从COM/DCOM技术切换到最先进的web服务。OPC基金会也一直在开发OPC UA工具包，该工具包提供了一系列库、类和接口，使开发人员和程序员能够轻松地创建和实现OPC UA组件。然而，由于该工具包的局限性，以及相关决策任务和信息系统的复杂性等原因，该工具包不足以让开发人员和程序员实现真正的工业监控应用。本文利用OPC UA规范、面向服务架构(Service Oriented Architecture, SOA)、web服务、XML、OPC UA SDK等技术，提出并开发了一个OPC UA (Unified Architecture)客户端框架。这个框架最大限度地减少了开发人员和程序员学习新技术的工作量，并允许系统架构师和设计人员对监视和控制应用程序的开发执行依赖分析。本文还提供了由Visual Studio 2008实现的系统的初步结果。
{"title":"An OPC UA client development for monitoring and control applications","authors":"S. mai, V. Vu, Myeongjae Yi","doi":"10.1109/IFOST.2011.6021120","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021120","url":null,"abstract":"Classic OPC, released by OPC Foundation, is well accepted and applied in industrial automation, which led to many OPC products on the market from a variety of companies. However, OPC technology was based on retiring Microsoft COM/DCOM. The OPC Unified Architecture was introduced as the new generation specification with the main goal of keeping all the functionality of Classic OPC and switching from COM/DCOM technology to state -of-the-art web services. The OPC Foundation has been also developing OPC UA Toolkit that provide a collection of libraries, classes, and interfaces which make developers and programmers easy to create and implement OPC UA components. However, this toolkit is insufficient for developers and programmers to implement real monitoring and control applications from industry due to the limitations of such a toolkit, the complexity of related decision tasks and information systems, etc. In this paper, an OPC UA (Unified Architecture) client framework is proposed and developed by using OPC UA specifications, Service Oriented Architecture (SOA), web services, XML, OPC UA SDK, etc. This framework minimizes the efforts of developers and programmers in learning new techniques and allows system arc hitects and designers to perform dependency analysis on the development of monitoring and control applications. The initial results from the system implemented by Visual Studio 2008 are also provided.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79877087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021257
B. Dorjsuren
The main light-climatically characteristics, such as duration of natural illumination, light-climatically coefficient, standardize values of the coefficient natural illuminations for buildings (en) situated in some regions of Mongolia and the variability of natural illumination have been determined. The first study of geophysical and astronomical factors effecting the natural illumination regime and interconnection among the atmospheric transparency (P2) with natural illumination of horizontal earth surfaces in Ulaanbaatar was also investigated.
{"title":"The main results of study of light-climates earth's surface on the Mongolian territory","authors":"B. Dorjsuren","doi":"10.1109/IFOST.2011.6021257","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021257","url":null,"abstract":"The main light-climatically characteristics, such as duration of natural illumination, light-climatically coefficient, standardize values of the coefficient natural illuminations for buildings (en) situated in some regions of Mongolia and the variability of natural illumination have been determined. The first study of geophysical and astronomical factors effecting the natural illumination regime and interconnection among the atmospheric transparency (P2) with natural illumination of horizontal earth surfaces in Ulaanbaatar was also investigated.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89229783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-09-15DOI: 10.1109/IFOST.2011.6021204
Chao An, Mei Yu
Based on the assumption of spatially smooth illuminant, traditional Retinex enhancement methods suffer the existence of halo artifacts. According to its drawback, add to the advantage of MSRCR, we propose a fast fuzzy multiple-scale Retinex color image enhancement method. The new Retinex method restricts the center/surround spatially contrast operation in region with homogeneous illumination, experimental results demonstrate that our method efficiently reduces halo artifacts. Meanwhile, we use an adaptive Gaussian mask to reduce the computational time. Experimental results are given to show its effectiveness.
{"title":"Fast color image enhancement based on fuzzy multiple-scale Retinex","authors":"Chao An, Mei Yu","doi":"10.1109/IFOST.2011.6021204","DOIUrl":"https://doi.org/10.1109/IFOST.2011.6021204","url":null,"abstract":"Based on the assumption of spatially smooth illuminant, traditional Retinex enhancement methods suffer the existence of halo artifacts. According to its drawback, add to the advantage of MSRCR, we propose a fast fuzzy multiple-scale Retinex color image enhancement method. The new Retinex method restricts the center/surround spatially contrast operation in region with homogeneous illumination, experimental results demonstrate that our method efficiently reduces halo artifacts. Meanwhile, we use an adaptive Gaussian mask to reduce the computational time. Experimental results are given to show its effectiveness.","PeriodicalId":20466,"journal":{"name":"Proceedings of 2011 6th International Forum on Strategic Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88276611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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