The Experts below are selected from a list of 11331 Experts worldwide ranked by ideXlab platform

Yongxian Huang - One of the best experts on this subject based on the ideXlab platform.

  • Joint formation mechanism of high depth-to-width ratio friction stir welding
    Journal of Materials Science & Technology, 2019
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Li Zhou
    Abstract:

    Abstract High depth-to-width ratio friction stir welding is an attractive method for the joining demands of aluminum profiles, which is sparked with its extremely low heat input and high mechanical performance. In this study, the joint formation mechanism was studied by a numerical model of plastic flow combined with experimental approaches. A fluid-solid-interaction algorithm was proposed to establish the coupling model, and the material to be welded was treated as non-Newtonian fluid. The Thread Structure and the milling facets on tool pin promoted drastic turbulence of material. The Thread Structure converged the plasticized material by its inclined plane, and then drove the attached material to refill the welds. The milling facets brought about the periodic dynamic material flow. The Thread Structure and the milling facets increased the strain rate greatly under the extremely low heat input, which avoided the welding defects. The condition of the peak temperature of 648 K and the strain rate of 151 s−1 attributed to the lowest coarsening degree of precipitate. The tensile strength of the joint reached 265 MPa, equivalent to 86% of base material. The amelioration via the material flow model inhibits the welding defects and optimizes the parameter intervals, providing references to extracting process-Structure-property linkages for friction stir welding.

  • Numerical design of high depth-to-width ratio friction stir welding
    Journal of Materials Processing Technology, 2018
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Jian Cao
    Abstract:

    Abstract Tools with a high depth-to-width ratio of 0.6 were designed and tested. The Thread Structure of pin could promote material flow but increase fracture risk. The pins with milling facets were more beneficial to achieve sound joint. The tapered Thread tool with triple facets was the optimal Structure for high depth-to-width ratio friction stir welding at a rotational speed of 800 rpm and a welding speed of 30 mm/min. The measured temperature and joint formation agreed with the predicted data well. A narrower average heat affected zone with the width of 440 μm was obtained, which was far lower than that underwater friction stir welding.

Jian Cao - One of the best experts on this subject based on the ideXlab platform.

  • Numerical design of high depth-to-width ratio friction stir welding
    Journal of Materials Processing Technology, 2018
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Jian Cao
    Abstract:

    Abstract Tools with a high depth-to-width ratio of 0.6 were designed and tested. The Thread Structure of pin could promote material flow but increase fracture risk. The pins with milling facets were more beneficial to achieve sound joint. The tapered Thread tool with triple facets was the optimal Structure for high depth-to-width ratio friction stir welding at a rotational speed of 800 rpm and a welding speed of 30 mm/min. The measured temperature and joint formation agreed with the predicted data well. A narrower average heat affected zone with the width of 440 μm was obtained, which was far lower than that underwater friction stir welding.

Yuming Xie - One of the best experts on this subject based on the ideXlab platform.

  • Joint formation mechanism of high depth-to-width ratio friction stir welding
    Journal of Materials Science & Technology, 2019
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Li Zhou
    Abstract:

    Abstract High depth-to-width ratio friction stir welding is an attractive method for the joining demands of aluminum profiles, which is sparked with its extremely low heat input and high mechanical performance. In this study, the joint formation mechanism was studied by a numerical model of plastic flow combined with experimental approaches. A fluid-solid-interaction algorithm was proposed to establish the coupling model, and the material to be welded was treated as non-Newtonian fluid. The Thread Structure and the milling facets on tool pin promoted drastic turbulence of material. The Thread Structure converged the plasticized material by its inclined plane, and then drove the attached material to refill the welds. The milling facets brought about the periodic dynamic material flow. The Thread Structure and the milling facets increased the strain rate greatly under the extremely low heat input, which avoided the welding defects. The condition of the peak temperature of 648 K and the strain rate of 151 s−1 attributed to the lowest coarsening degree of precipitate. The tensile strength of the joint reached 265 MPa, equivalent to 86% of base material. The amelioration via the material flow model inhibits the welding defects and optimizes the parameter intervals, providing references to extracting process-Structure-property linkages for friction stir welding.

  • Numerical design of high depth-to-width ratio friction stir welding
    Journal of Materials Processing Technology, 2018
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Jian Cao
    Abstract:

    Abstract Tools with a high depth-to-width ratio of 0.6 were designed and tested. The Thread Structure of pin could promote material flow but increase fracture risk. The pins with milling facets were more beneficial to achieve sound joint. The tapered Thread tool with triple facets was the optimal Structure for high depth-to-width ratio friction stir welding at a rotational speed of 800 rpm and a welding speed of 30 mm/min. The measured temperature and joint formation agreed with the predicted data well. A narrower average heat affected zone with the width of 440 μm was obtained, which was far lower than that underwater friction stir welding.

Xiangchen Meng - One of the best experts on this subject based on the ideXlab platform.

  • Joint formation mechanism of high depth-to-width ratio friction stir welding
    Journal of Materials Science & Technology, 2019
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Li Zhou
    Abstract:

    Abstract High depth-to-width ratio friction stir welding is an attractive method for the joining demands of aluminum profiles, which is sparked with its extremely low heat input and high mechanical performance. In this study, the joint formation mechanism was studied by a numerical model of plastic flow combined with experimental approaches. A fluid-solid-interaction algorithm was proposed to establish the coupling model, and the material to be welded was treated as non-Newtonian fluid. The Thread Structure and the milling facets on tool pin promoted drastic turbulence of material. The Thread Structure converged the plasticized material by its inclined plane, and then drove the attached material to refill the welds. The milling facets brought about the periodic dynamic material flow. The Thread Structure and the milling facets increased the strain rate greatly under the extremely low heat input, which avoided the welding defects. The condition of the peak temperature of 648 K and the strain rate of 151 s−1 attributed to the lowest coarsening degree of precipitate. The tensile strength of the joint reached 265 MPa, equivalent to 86% of base material. The amelioration via the material flow model inhibits the welding defects and optimizes the parameter intervals, providing references to extracting process-Structure-property linkages for friction stir welding.

  • Numerical design of high depth-to-width ratio friction stir welding
    Journal of Materials Processing Technology, 2018
    Co-Authors: Yongxian Huang, Yuming Xie, Xiangchen Meng, Jian Cao
    Abstract:

    Abstract Tools with a high depth-to-width ratio of 0.6 were designed and tested. The Thread Structure of pin could promote material flow but increase fracture risk. The pins with milling facets were more beneficial to achieve sound joint. The tapered Thread tool with triple facets was the optimal Structure for high depth-to-width ratio friction stir welding at a rotational speed of 800 rpm and a welding speed of 30 mm/min. The measured temperature and joint formation agreed with the predicted data well. A narrower average heat affected zone with the width of 440 μm was obtained, which was far lower than that underwater friction stir welding.

Ichiro Ide - One of the best experts on this subject based on the ideXlab platform.

  • ICMR - Estimation of the Representative Story Transition in a Chronological Semantic Structure of News Topics
    Proceedings of International Conference on Multimedia Retrieval, 2014
    Co-Authors: Kosuke Kato, Ichiro Ide, Daisuke Deguchi, Hiroshi Murase
    Abstract:

    It is important to track the flow of topics to thoroughly understand the contents. Accordingly, a method that Structures the chronological semantic relations between news stories, namely a "topic Thread Structure" has been proposed. It allows the comprehensive understanding of a topic by chronologically tracking stories one by one from the initial story. However, this task imposes a user to watch many stories when it contains various sub-topics. Thus, we propose a method that estimates the representative story transition in a topic Thread Structure. In the proposed method, features obtained from a story and those from the topic Thread Structure are used for the estimation. We confirmed the effectiveness of the proposed method by comparing the results obtained from the proposed method to the ground truth obtained from votes in a subjective experiment.

  • Efficient Tracking of News Topics Based on Chronological Semantic Structures in a Large-Scale News Video Archive ∗
    IEICE Transactions on Information and Systems, 2012
    Co-Authors: Ichiro Ide, Tomoyoshi Kinoshita, Tomokazu Takahashi, Norio Katayama, Shin'ichi Satoh, Murase Hiroshi, Hiroshi Murase
    Abstract:

    SUMMARY Recent advance in digital storage technology has enabled us to archive a large volume of video data. Thanks to this trend, we have archived more than 1,800 hours of video data from a daily Japanese news show in the last ten years. When considering the effective use of such a large news video archive, we assumed that analysis of its chronological and semantic Structure becomes important. We also consider that providing the users with the development of news topics is more important to help their understanding of current affairs, rather than providing a list of relevant news stories as in most of the current news video retrieval systems. Therefore, in this paper, we propose a structuring method for a news video archive, together with an interface that visualizes the Structure, so that users could track the development of news topics according to their interest, efficiently. The proposed news video Structure, namely the “topic Thread Structure”, is obtained as a result of an analysis of the chronological and semantic relation between news stories. Meanwhile, the proposed interface, namely “mediaWalker II”, allows users to track the development of news topics along the topic Thread Structure, and at the same time watch the video footage corresponding to each news story. Analyses on the topic Thread Structures obtained by applying the proposed method to actual news video footages revealed interesting and comprehensible relations between news topics in the real world. At the same time, analyses on their size quantified the efficiency of tracking a user’s topic-of-interest based on the proposed topic Thread Structure. We consider this as a first step towards facilitating video authoring by users based on existing contents in a large

  • mediaWalker: Tracking and browsing news video along the topic Thread Structure
    2011
    Co-Authors: Ichiro Ide, Hiroshi Murase, Tomoyoshi Kinoshita, Tomokazu Takahashi, Frank Nack
    Abstract:

    We introduce a news video tracking and browsing interface “mediaWalker” that allows users to explore throughout a news video archive by tracking news topics along a chronological semantic Structure of news stories.

  • Proposal of an Information Compilation Method for Massive News Video Data Based on their Time-Series Semantic Structure
    Transactions of the Japanese Society for Artificial Intelligence, 2008
    Co-Authors: Ichiro Ide, Tomoyoshi Kinoshita, Tomokazu Takahashi, Norio Katayama, Shin'ichi Satoh, Hiroshi Murase
    Abstract:

    Recent increase of digital storage capacity has enabled the creation of large-scale on-line broadcast video archives. In order to make full use of the data in the archive, it is necessary to let a user easily grasp the availability of certain video data and their contents. Considering this problem, we have been investigating efficient and effective retrieval and reusing methodologies of archived video data. The archive used as a test-bed consists of more than 1,000 hours of news video obtained from a Japanese news program during the past six years. This paper first proposes a news topic tracking and structuring method. A Structure called the `topic Thread Structure', is organized so that it should represent the temporal flow of news topics originating from a specified news story. The paper next introduces a browsing and editing interface that enables the user to browse through news stories along the topic Thread Structure, and also assists the compilation of selected news stories as a customized video summary or a documentary. The method was applied to the archived news video data in order to observe the quality of the topic Thread Structure and the usability of the prototype interface. As a result, some Structures represented the flow of topics quite close to real-world comprehension. In addition, experiments showed that when the Structure could be considered meaningful, the interface combined with the Structure could drastically reduce the time needed to browse through the archive for news stories related to the user's interest.

  • ACM Multimedia - mediaWalker: a video archive explorer based on time-series semantic Structure
    Proceedings of the 15th international conference on Multimedia - MULTIMEDIA '07, 2007
    Co-Authors: Ichiro Ide, Tomoyoshi Kinoshita, Tomokazu Takahashi, Shin'ichi Satoh, Hiroshi Murase
    Abstract:

    We introduce a video browsing interface 'mediaWalker' that lets users explore a news video archive based on a time-series semantic Structure; the 'topic Thread' Structure. The interface lets users efficiently track up and down the development of news in an archive with more than 1,000 hours of video.