• 제목/요약/키워드: identification

검색결과 19,872건 처리시간 0.04초

Numerical studies on the effect of measurement noises on the online parametric identification of a cable-stayed bridge

  • Yang, Yaohua;Huang, Hongwei;Sun, Limin
    • Smart Structures and Systems
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    • 제19권3호
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    • pp.259-268
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    • 2017
  • System identification of structures is one of the important aspects of structural health monitoring. The accuracy and efficiency of identification results is affected severely by measurement noises, especially when the structure system is large, such as bridge structures, and when online system identification is required. In this paper, the least square estimation (LSE) method is used combined with the substructure approach for identifying structural parameters of a cable-stay bridge with large degree of freedoms online. Numerical analysis is carried out by first dividing the bridge structure into smaller substructures and then estimates the parameters of each substructure online using LSE method. Simulation results demonstrate that the proposed approach is capable of identifying structural parameters, however, the accuracy and efficiency of identification results depend highly on the noise sensitivities of loading region, loading pattern as well as element size.

고속 하틀리 변환에 의한 의약품 미분스펙트럼의 확인 시스템의 개발 (Development of Identification System of Derivative Spectra of Pharmaceuticals by Fast Hartley Transform)

  • 이숙연;노일협;박만기;박정일;조정환
    • 약학회지
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    • 제35권1호
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    • pp.1-6
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    • 1991
  • Fast Hartley transform(FHT) was used for the identification of derivative UV spectra of pharmaceuticals, with the advantages of relatively shorter computing time of FHT and more precise results. The arccosine value of dot product of two vectors of normalized FHT coefficients calculated from two compared derivative spectra was a reasonable parameter for the spectral identification. Using this parameter, the similar patterns of derivative spectra of 13 penicillins can be differenciated from each other. The concentration difference and the minor contamination did not interfere the results of identification procedures. All these procedures of identification were accomplished successfully by the computer program, [SPECMAN PLUS] version 1.30, which was developed for this article.

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한국방공식별구역(KADIZ) 발전방안 (The Development Option for Korea Air Defense Identification Zone(KADIZ))

  • 김동수;홍성표;정맹석
    • 항공우주시스템공학회지
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    • 제10권1호
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    • pp.127-132
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    • 2016
  • Recently, China & Japan have expanded their responding ADIZ(Air Defence Identification Zone) to implement each Government's maritime policy and to project their Air Power in preparation for maritime provocation & contingency, especially over the piled area where East Asia countries have claimed to have maritime jurisdiction one another. So this is to guide the Development Option for Korea Air Defence Identification Zone to cope with the maritime intentions of the neighboring countries, considering the international law for ADIZ, the maritime policy and the maritime sovereign & jurisdiction area of the Republic of Korea, etc.

An Efficient Identification of 68 Apple Cultivars Using a Cultivar Identification Diagram (CID) Strategy and RAPD Markers

  • Wang, Wenyan;Wang, Kun;Liu, Fengzhi;Fang, Jinggui
    • 원예과학기술지
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    • 제30권5호
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    • pp.549-556
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    • 2012
  • The study aimed to establish an efficient tool for cultivar identification and characterization being the first steps of apple introduction and improvement program. We utilized a method to efficiently record DNA molecular fingerprints of plant individuals genotyped by RAPD, which could be used as efficient reference information for quick plant identification. Ten of sixty 11-mer primers were screened to identify the 68 apple genotypes which could be distinguished by a combination of several primers. All cultivars were easily identified by the corresponding primers marked on the cultivar identification diagram (CID). The results indicated that the CID strategy developed and employed in the apple cultivar identification could be vital in the utilization of DNA marker in other plants as well as the development of the apple industry.

Vibration-based Identification of Directional Damages in a Cylindrical Shell

  • Kim, Sung-Hwan;Oh, Hyuk-Jin;Lee, U-Sik
    • 비파괴검사학회지
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    • 제25권3호
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    • pp.178-188
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    • 2005
  • This paper introduces a structural damage identification method to identify 4he multiple directional damages generated within a cylindrical shell by using the measured frequency response function (FRF). The equations of motion for a damaged cylindrical shell are derived. by using a theory of continuum damage mechanics in which a small material volume containing a directional damage is represented by the effective orthotropic elastic stiffness. In contrast with most existing vibration-based structural damage identification methods which require the modal Parameters measured in both intact and damaged states, the present method requires only the FRF-data measured at damaged state. Numerically simulated damage identification tests are conducted to verify the feasibility of the Proposed structural damage identification method.

Structural damage identification using incomplete static displacement measurement

  • Lu, Z.R.;Zhu, J.J.;Ou, Y.J.
    • Structural Engineering and Mechanics
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    • 제63권2호
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    • pp.251-257
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    • 2017
  • A local damage identification method using measured structural static displacement is proposed in this study. Based on the residual force vector deduced from the static equilibrium equation, residual strain energy (RSE) is introduced, which can localize the damage in the element level. In the case of all the nodal displacements are used, the RSE can localize the true location of damage, while incomplete displacement measurements are used, some suspicious damaged elements can be found. A model updating method based on static displacement response sensitivity analysis is further utilized for accurate identification of damage location and extent. The proposed method is verified by two numerical examples. The results indicate that the proposed method is efficient for damage identification. The advantage of the proposed method is that only limited static displacement measurements are needed in the identification, thus it is easy for engineering application.

A gender identification using shoeprint images

  • Asamizu, Satoshi;Haseyama, Miki
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.699-702
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    • 2009
  • This paper proposes a gender identification using shoeprint images. It is difficult for the proposed method to identify an individual if shoeprint images for identification leaked out. Because the proposed method identifies gender without the faces, the type of dress and the hair types images. Therefore we can use safely the proposed method in public place. In addition, a sensor mat which we developed is reasonable to use mechanical switches arranged in a matrix pattern without pressure switches. We had shoeprint images with the sensor mat. We measure feature parameters from shoeprint images. The feature parameters are length, width and area of shoeprint. Utilizing the feature parameters, we identified gender. In order to verify the gender identification rate of the proposed method, we set up the sensor mat at an entrance of buildings and took shoeprint images of 100 men and 100 women. As a result, we achieved about 86 percent of the gender identification rate.

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Parameter Identification of Induction Motors using Variable-weighted Cost Function of Genetic Algorithms

  • Megherbi, A.C.;Megherbi, H.;Benmahamed, K.;Aissaoui, A.G.;Tahour, A.
    • Journal of Electrical Engineering and Technology
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    • 제5권4호
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    • pp.597-605
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    • 2010
  • This paper presents a contribution to parameter identification of a non-linear system using a new strategy to improve the genetic algorithm (GA) method. Since cost function plays an important role in GA-based parameter identification, we propose to improve the simple version of GA, where weights of the cost function are not taken as constant values, but varying along the procedure of parameter identification. This modified version of GA is applied to the induction motor (IM) as an example of nonlinear system. The GA cost function is the weighted sum of stator current and rotor speed errors between the plant and the model of induction motor. Simulation results show that the identification method based on improved GA is feasible and gives high precision.

윤리적 리더십이 조직동일시와 조직몰입에 미치는 영향 (The Effects of Ethical Leadership on Organizational Identification and Organizational Commitment)

  • 황상규
    • 대한안전경영과학회지
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    • 제16권4호
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    • pp.285-294
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    • 2014
  • The paper examines how ethical leadership and organizational identification contributed to explaining organizational commitment. In order to verify the relationships and mediating effect, data were collected from 256 individuals in employees working in small and medium-sized firms at Jinju, Changwon, Gimhae City to test theoretical model and its hypotheses. All data collected from the survey were analyzed using with SPSS 18.0. This study reports findings as follows: first, the relationship between the ethical leadership and the organizational identification is positively related. Second, there was also a positive correlation between the organizational identification and the organizational commitment. Third, the relationship between the ethical leadership and the organizational commitment is positively related. Finally, the organizational identification played as a partial mediator on the relationship between ethical leadership and organizational commitment. Based on these findings, the implications and the limitations of the study were presented including some directions for future studies.

철도교량의 손상도 평가기법 개발에 관한 연구 (A Damage Identification for Railway Bridges using Static Response)

  • 최일윤;이준석;이종순;조효남
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(II)
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    • pp.1065-1073
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    • 2002
  • A new damage identification technique using static displacement data is developed to assess the structural integrity of bridge structures. In the conventional damage assessment techniques using dynamic response, it is usually difficult to obtain a significant natural frequencies variation from the measured data because the natural frequencies variation is intrinsically not sensitive to the damage of a bridge. In this proposed identification method, the stiffness reduction of the bridges can be estimated using the static displacement data measured periodically and a specific loading test is not required. The static displacement data due to the dead load of the bridge structure can be measured by devices such as a laser displacement sensor. In this study, structural damage is represented by the reduction in the elastic modulus of the element. The damage factor of the element is introduced to estimate the stiffness reduction of the bridge under consideration. Finally, the proposed algorithm is verified using various numerical simulation and compared with other damage identification method. Also, the effect of noise and number of damaged elements on the identification are investigated. The results show that the proposed algorithm is efficient for damage identification of the bridges.

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