RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        Numerical study of rock-breaking performance of cutters in heterogeneous sand cobble ground

        Jin Guo,Xiangwei Kong,Liu Cheng,Xueyi Li 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.6

        Further research into tunneling performance in heterogeneous sand cobble ground demands an accurate numerical model of actual formation. In this paper, the ground model composed of spherical sand and ellipsoidal cobble was constructed to study the rockbreaking performance by using the discrete element method. The shape and physical parameters of sand and cobble were obtained on the basis of field test data. Then, the ground model was constructed to simulate the rock-breaking process of the cutterhead. The results show that the center cutter has a high flat wear percentage. With the decrease in cobble content (CC), the cracks between cutters are not connected effectively, thereby resulting in lower rock-breaking quantity. Finally, the influences of CC on the optimal parameters and crack propagation were analyzed. The results indicate that the rock-breaking performance in the ground with a low CC can be improved by increasing penetration and reducing cutter spacing.

      • KCI등재

        Weibull parameter estimation and reliability analysis with small samples based on successive approximation method

        Jin Guo,Xiangwei Kong,Ningxiang Wu,Liyang Xie 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.11

        Only few failure data can be collected because of increasing costs and reliability. Therefore, improving the estimation accuracy of Weibull distribution with small samples has become an urgent problem. In this study, a method for estimating the Weibull parameter and analyzing reliability is proposed based on the successive approximation method. In this method, the effect of sample size on the location parameter is considered to establish an iterative model of the location parameter. The iterative equations of scale and shape parameters are constructed based on the location parameter and failure data. Then, an extensive MonteCarlo simulation study is conducted to compare the performance of the proposed method with the existing methods. Simulation results show that the proposed method is superior for estimating Weibull parameters and reliability in terms of precision, robustness, and efficiency. Finally, two real examples are analyzed to illustrate the application of the proposed method.

      • KCI등재

        Classifier Combination Based Source Identification for Cell Phone Images

        ( Bo Wang ),( Yue Tan ),( Meijuan Zhao ),( Yanqing Guo ),( Xiangwei Kong ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.12

        Rapid popularization of smart cell phone equipped with camera has led to a number of new legal and criminal problems related to multimedia such as digital image, which makes cell phone source identification an important branch of digital image forensics. This paper proposes a classifier combination based source identification strategy for cell phone images. To identify the outlier cell phone models of the training sets in multi-class classifier, a one-class classifier is orderly used in the framework. Feature vectors including color filter array (CFA) interpolation coefficients estimation and multi-feature fusion is employed to verify the effectiveness of the classifier combination strategy. Experimental results demonstrate that for different feature sets, our method presents high accuracy of source identification both for the cell phone in the training sets and the outliers.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼