DEStech Transactions on Materials Science and Engineering最新文献

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Cracks Forming and Propagation Mechanism for the Q345 Steel during Cooling Q345钢冷却过程裂纹形成及扩展机理
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35530
Lijun Xu, Yong Shuai, J. Yuan, Shu-lan Zhang
{"title":"Cracks Forming and Propagation Mechanism for the Q345 Steel during Cooling","authors":"Lijun Xu, Yong Shuai, J. Yuan, Shu-lan Zhang","doi":"10.12783/DTMSE/AMEME2020/35530","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35530","url":null,"abstract":"Cracks always occur for the Q345 steel during cooling, which usually lead to Welding failure. Through investigation of the cracks forming position and propagation path, its forming and propagation mechanism for the melted Q345 steel during cooling was studied in detail by using of SEM, EBSD and Nano Indenter equipment in this paper. SEM observation results imply that cracks mainly initiated at martensite phase region close to basal material. Moreover, it also can be observed that the cracks always propagated along the martensite lath or packets boundaries, but not the original prior austenite grain boundaries. The hardness differences between cracks adjacent positions and matrix is about 2.48 GPa, which is larger than that of melted region and matensite (0.70GPa). In addition, EBSD results show that the average prior austenite grains boundaries angles (30-50o) are always smaller than that of martensite lath and packet boundaries (>50o). Combining investigation of the cracks forming position, propagation path and microstructure misorientation, it proves that the occurrence of the cracks at junction of martensite phase region close to basal material is related with larger hardness difference or larger residual stress between martensite and ferrite, while cracks propagation path is controlled by the boundaries angles or local misorientation. The cracks incline to propagate along or deflect to large martensite lath and packets boundaries.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87920884","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}
引用次数: 0
Promote the Development of Integrated Energy Service Industry with Platform Mode 以平台模式推动综合能源服务业发展
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35582
Yazong Mai, Gaoqi Dai, Jie Li
{"title":"Promote the Development of Integrated Energy Service Industry with Platform Mode","authors":"Yazong Mai, Gaoqi Dai, Jie Li","doi":"10.12783/DTMSE/AMEME2020/35582","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35582","url":null,"abstract":"In recent years, integrated energy service industry has entered a stage of rapid development in China. Quantities of domestic energy companies and technology companies have deployed and expanded integrated energy service businesses. Moreover, integrated energy services based on the platform model is currently a development direction that has attracted much attention. This article analyses the development status and trends of the domestic platform market of integrated energy service. We also study on the functional positioning and development mode of building an integrated energy service platform. Then we propose the main services functions and business scenarios of the platform. Finally, this paper puts forward relevant suggestions to promote the development of integrated energy service industry platform. As the energy revolution, digital revolution, and industrial revolution continue to crossintegrate, new development concepts such as green and low-carbon, \"Internet +\", and digital transformation have accelerated their penetration into the energy sector. And integrated energy services have become an important development direction to improve energy efficiency, reduce energy costs, and promote competition and cooperation. Facing the huge market of integrated energy services, domestic advanced enterprises have built integrated energy service platforms. With the application of new technologies such as cloud computing, big data, the internet of things, mobile internet, artificial intelligence\", an integrated energy data information network will be built to master and operate user data. It can not only explore and innovate products of integrated energy service, but also better meet customers’ needs and enhance core competitiveness in the market. 1 Development status of the integrated energy service market Currently, the domestic integrated energy service market has the following characteristics: First, the integrated energy service involves a wide range of business types. It is comprehensive and covers a wide range, including basic energy sales such as electricity, gas and heat. It also includes basic distributed energy projects such as plan, design, construction and operation of distributed photovoltaic, cooling, heating and power generation of natural gas, biomass boilers, energy storage, heat pumps, etc. In addition, it","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":" 572","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91410049","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}
引用次数: 0
A Running Pattern Recognition Algorithm for Publish/Subscribe Distributed Systems 面向发布/订阅分布式系统的运行模式识别算法
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35562
Wen-Jen Wu, Zhuowei Shen, Defeng Wang
{"title":"A Running Pattern Recognition Algorithm for Publish/Subscribe Distributed Systems","authors":"Wen-Jen Wu, Zhuowei Shen, Defeng Wang","doi":"10.12783/DTMSE/AMEME2020/35562","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35562","url":null,"abstract":"Publish/subscribe distributed systems are often used in critical applications. It is necessary to monitor their running patterns in real time to detect abnormal status. Therefore, identifying the normal running pattern is the precondition of monitoring publish/subscribe distributed systems. Based on Apriori algorithm, this paper presents a weighted frequent itemset mining algorithm for running pattern recognition of publish/subscribe distributed systems. By introducing the transaction matrix, the algorithm only needs to scan the transaction database once. By weighting the items from two aspects of influence and frequency, the support of the items with few occurrences but much importance can be improved, so that the running pattern containing small frequency events can be mined out. Experimental results show that the algorithm can effectively mine the running patterns, and has better performance than Apriori algorithm and FP-growth algorithm.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"104 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80671438","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}
引用次数: 0
Design of Polyphase Channelization Algorithm Based on CUDA Stream Architecture 基于CUDA流架构的多相信道化算法设计
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35540
Chen Yongqiang, Hong Ma, Jiao Yiwen, Hongjie Dang
{"title":"Design of Polyphase Channelization Algorithm Based on CUDA Stream Architecture","authors":"Chen Yongqiang, Hong Ma, Jiao Yiwen, Hongjie Dang","doi":"10.12783/DTMSE/AMEME2020/35540","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35540","url":null,"abstract":"In order to improve the reconfigurability and computing efficiency of the polyphase channelization system, a new algorithm based on CUDA stream architecture was designed and optimized. Firstly, the principle of parallel channelization algorithm without blind zones is introduced. Then, various resource constraints under CUDA architecture and the relationship between the operating efficiency and parameters of the CUDA kernel under these constraints are analysed. The implementation structure of polyphase channelization algorithm is designed. Finally, NVIDIA GPU is used to implement and test the polyphase channelization algorithm based on CUDA stream. The result proves that the computational efficiency of the structure designed in this paper meets the real-time requirements, and can get about 10% efficiency improvement compared with the traditional algorithm.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"4 s2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91427309","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}
引用次数: 0
Construction of Semi-Bianisotropic Conductive Janus-Structure Membrane Offering Magnetism and Fluorescence by Utilizing Different Functional Blocks 利用不同功能块构建具有磁性和荧光的半双各向异性导电双面结构膜
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35552
Yunrui Xie, H. Qi, Q. Ma, Li Dan, Wensheng Yu, Guixia Liu, Xiang-ting Dong
{"title":"Construction of Semi-Bianisotropic Conductive Janus-Structure Membrane Offering Magnetism and Fluorescence by Utilizing Different Functional Blocks","authors":"Yunrui Xie, H. Qi, Q. Ma, Li Dan, Wensheng Yu, Guixia Liu, Xiang-ting Dong","doi":"10.12783/DTMSE/AMEME2020/35552","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35552","url":null,"abstract":"A new concept of semi-bianisotropic conductivity is put forward based on modularization design. Half of the material has dual anisotropic conductivity while the other half has single anisotropic conductivity by adjusting areas of the two surfaces endowed with anisotropic conductivity and vertically arranged up to down. Semibianisotropic conductive Janus-structure membrane affording magnetism and fluorescence (SCMF) is prepared by constructing three blocks via electro-spinning. Three blocks, including C-R block (top), M-G block and C-R block (down), are assembled into SCMF. Janus-structure nanobelts are selected as building units to gain micro zoning. Modular structure further prevents negative interactions among various functional substances. SCMF has bicolor luminescence and variable magnetism. SCMF gains tuned semi-bianisotropic conductivity, where the area of C-R block (top) with single conductive aeolotropism is half of C-R block (down) with single conductive aeolotropism, so half of SCMF has double conductive aeolotropism and other half of SCMF has single conductive aeolotropism.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"110 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83741286","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}
引用次数: 0
Research on Industry Index Fluctuation of Stock Market Based on SV-T Model 基于SV-T模型的股票市场行业指数波动研究
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35566
Qian Li, Juying Xi, Shuo Wang
{"title":"Research on Industry Index Fluctuation of Stock Market Based on SV-T Model","authors":"Qian Li, Juying Xi, Shuo Wang","doi":"10.12783/DTMSE/AMEME2020/35566","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35566","url":null,"abstract":"In a complex market environment, it is important to describe and predict the volatility of returns in various industries. In this paper, after ADF stability test is conducted on the return rate sequence of building materials, real estate, medicine biological, non-bank finance, and communication industry, SV-T modeling is carried out, and the parameter estimation range of SV-T model is obtained by using MCMC method and Winbugs software. After ten thousand iterations, under the condition that the Markov chain of parameters obtained by Gibbs sampling method converges, the parameter estimation results of SV-T model are obtained. According to the parameter estimation results of SV-T model in each industry, the difference of investment risk and volatility predictability among five target industries is compared and analyzed.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89051550","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}
引用次数: 0
A Path Loss Statistical Model for On-Body WBAN 一种体上无线宽带网络的路径损耗统计模型
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35564
Yihuai Yang
{"title":"A Path Loss Statistical Model for On-Body WBAN","authors":"Yihuai Yang","doi":"10.12783/DTMSE/AMEME2020/35564","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35564","url":null,"abstract":"Wireless Body Area Network (WBAN) is a new and promising wireless communication technology which consists several sensors around, on or even implant into human bodies to sense importance human physical signals. In order to erect and develop a robust WBAN, accurate modeling of the body-area network radio-propagation channel and understand the statistical characteristics in close proximity to the human body are required. In this paper, we focus on study the on-body to on-body WBAN path loss model, the environments factors are considered. The statistical parameters are extracted form measurements data, the proposed path loss model is validated through comparison with a measurement-based approach. Introduction Wireless Body Area Networks (WBANs) consist of wireless sensors attached on or inside the human body to provide real-time and reliable health monitoring. WBANs have been paid much attention in order to offer flexibilities and cost saving options to both health care professionals and patients[1][2]. Attributing to the signal processing, miniaturization of hardware, wireless communication, medical sensors, and biomedical engineering, WBANs have become a key component of the ubiquitous e-Health revolution that prospers on the basis of information and communication technologies. In order to evaluate different forthcoming proposals for WBANs and properly design and develop medical radio service bands devices for use in WBANs, channel models are required. A channel model is an essential piece of a physical layer communication simulation. It is a mathematical representation of the effects of a communication channel through which wireless signals are propagated. In general, the channel impulse response of a wireless communication system varies randomly over time. By using the right channel model in your design, you can optimize link performance, perform system architecture trade offs, and provide a realistic assessment of the overall system performance. In 2007, The IEEE 802.15 task group 6 (TG6) was established to develop a communication standard optimized for low power devices and operation for both in-body and on-body. The channel modeling subgroup released the final channel model for WBAN in July 2010 [3]. They defined the WBAN channel models for both in-body and on-body scenarios [3]. In addition to TG6, lots of studies have focused on WBAN channel measurement and modeling in different frequency bands and environments. Lots of studies have focused on WBAN channel measurement, modeling and MAC protocols problems[4]-[5]. However, the number of available measurements is insufficient. 376 This paper presents a preliminary analytical path loss model for on-body WBANs based on measurements method. In order to compare with IEEE802.15.6 CM3 model[8], the measurements are also carried out in the 400, 600, 900 MHz and 2.4, 3.1-10.6 GHz. 2 Wireless body area network Wireless body area network (WBAN) consists of a set of mobile and compact intercommunicating ","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82210383","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}
引用次数: 0
Computation of Kirchhoff Index in Generalized Ladders 广义阶梯中Kirchhoff指数的计算
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35556
Lei Zhang, Haizhen Ren
{"title":"Computation of Kirchhoff Index in Generalized Ladders","authors":"Lei Zhang, Haizhen Ren","doi":"10.12783/DTMSE/AMEME2020/35556","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35556","url":null,"abstract":"A connected graph G is viewed as an electrical network N by replacing each edge of G with a unit resistor. The Kirchhoff index of G is a structure-descriptor based on effective resistance of N. The generalized ladder is a subdivision graph of ladder graph. By using the properties of the Chebyshev polynomials, Laplace Theorem and so on, we obtained closed form expressions of Kirchhoff indexes for the generalized straight and generalized cyclic ladders, which generalize the results of linear quadrangular chain and linear hexagonal chain.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82545613","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}
引用次数: 0
A Correction Model of Troposphere Delay for GNSS Signal in the Dust and Haze Weather 沙尘和雾霾天气下GNSS对流层延迟的校正模型
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35580
Xinliang Cao, Luo Shouyu, N. Zhao, Rui Yang, Haisheng Huang
{"title":"A Correction Model of Troposphere Delay for GNSS Signal in the Dust and Haze Weather","authors":"Xinliang Cao, Luo Shouyu, N. Zhao, Rui Yang, Haisheng Huang","doi":"10.12783/DTMSE/AMEME2020/35580","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35580","url":null,"abstract":"Tropospheric delay is a factor that affects GNSS positioning accuracy, and the instability of the tropospheric refractive index is the cause of the deviation of tropospheric delay compensation. In the case of taking into account the atmospheric water vapor content and the atmospheric temperature of the station, this paper simplifies the establishment of a parametric refractive index correction model to replace the refractive index model that depends on meteorological factors. The parameters of the correction model are determined by the tropospheric layering method. The results show that under the same weather conditions, the accuracy in northern Shaanxi is higher than that in Guanzhong, and the correction value of refractive index is not ideal when it is far from the ground. Based on the model to estimate the ZTD, the results are compared with the results obtained by three IGS stations (LHAZ, BJFS, SHAO), which confirms that the accuracy of the ZTD estimation is generally improved by the model.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"14 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72583974","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}
引用次数: 0
Dynamic Simulation and Analysis of the Synchronous Mechanism of High-Speed Machine Tool Protective Cover with Joint Clearance 带关节间隙的高速机床防护罩同步机构动力学仿真与分析
DEStech Transactions on Materials Science and Engineering Pub Date : 2021-04-07 DOI: 10.12783/DTMSE/AMEME2020/35522
Tian Xia, Zhao Yihao, Mu Qi, Guo Jianbin, Yao Zhan
{"title":"Dynamic Simulation and Analysis of the Synchronous Mechanism of High-Speed Machine Tool Protective Cover with Joint Clearance","authors":"Tian Xia, Zhao Yihao, Mu Qi, Guo Jianbin, Yao Zhan","doi":"10.12783/DTMSE/AMEME2020/35522","DOIUrl":"https://doi.org/10.12783/DTMSE/AMEME2020/35522","url":null,"abstract":"The synchronous mechanism is the driving part of the machine tool guide rail protection device, which makes the relative speed of each cover sheet the same, which can well reduce the vibration and noise generated by the machine tool protection device. In high-speed operation, because the gap in the hinge pair of the synchronous mechanism has a great influence on its movement accuracy, this paper establishes a multibody dynamics model of the synchronous mechanism of the high-speed machine tool guide rail guard based on the Hertz theory, and uses ADAMS to The dynamic simulation analysis of the synchronous mechanism of the clearance shows that the pin near the joint between the worktable and the cover has the greatest influence on the motion accuracy of the synchronous mechanism. At the same time, the speed of the pin is analysed under different clearances. The transformation law of acceleration, contact and collision force of the kinematic pair with clearance and its influence on the performance of high-speed machine tool guards.","PeriodicalId":11124,"journal":{"name":"DEStech Transactions on Materials Science and Engineering","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80900086","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}
引用次数: 0
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