• Title/Summary/Keyword: identification key

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Structural damage identification with output-only measurements using modified Jaya algorithm and Tikhonov regularization method

  • Guangcai Zhang;Chunfeng Wan;Liyu Xie;Songtao Xue
    • Smart Structures and Systems
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    • v.31 no.3
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    • pp.229-245
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    • 2023
  • The absence of excitation measurements may pose a big challenge in the application of structural damage identification owing to the fact that substantial effort is needed to reconstruct or identify unknown input force. To address this issue, in this paper, an iterative strategy, a synergy of Tikhonov regularization method for force identification and modified Jaya algorithm (M-Jaya) for stiffness parameter identification, is developed for damage identification with partial output-only responses. On the one hand, the probabilistic clustering learning technique and nonlinear updating equation are introduced to improve the performance of standard Jaya algorithm. On the other hand, to deal with the difficulty of selection the appropriate regularization parameters in traditional Tikhonov regularization, an improved L-curve method based on B-spline interpolation function is presented. The applicability and effectiveness of the iterative strategy for simultaneous identification of structural damages and unknown input excitation is validated by numerical simulation on a 21-bar truss structure subjected to ambient excitation under noise free and contaminated measurements cases, as well as a series of experimental tests on a five-floor steel frame structure excited by sinusoidal force. The results from these numerical and experimental studies demonstrate that the proposed identification strategy can accurately and effectively identify damage locations and extents without the requirement of force measurements. The proposed M-Jaya algorithm provides more satisfactory performance than genetic algorithm, Gaussian bare-bones artificial bee colony and Jaya algorithm.

Protective Effects of the Ethanol Extract of Viola tianshanica Maxim against Acute Lung Injury Induced by Lipopolysaccharides in Mice

  • Wang, Xue;Yang, Qiao-Li;Shi, Yu-Zhu;Hou, Bi-Yu;Yang, Sheng-Qian;Huang, Hua;Zhang, Li;Du, Guan-Hua
    • Journal of Microbiology and Biotechnology
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    • v.27 no.9
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    • pp.1628-1638
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    • 2017
  • Viola tianshanica Maxim, belonging to the Violaceae plant family, is traditionally used in Uighur medicine for treating pneumonia, headache, and fever. There is, however, a lack of basic understanding of its pharmacological activities. This study was designed to observe the effects of the ethanol extract (TSM) from Viola tianshanica Maxim on the inflammation response in acute lung injury (ALI) induced by LPS and the possible underlying mechanisms. We found that TSM (200 and 500 mg/kg) significantly decreased inflammatory cytokine production and the number of inflammatory cells, including macrophages and neutrophils, in bronchoalveolar lavage fluid. TSM also markedly inhibited the lung wet-to-dry ratio and alleviated pathological changes in lung tissues. In vitro, after TSM ($12.5-100{\mu}g/ml$) treatment to RAW 264.7 cells for 1 h, LPS ($1{\mu}g/ml$) was added and the cells were further incubated for 24 h. TSM dose-dependently inhibited the levels of proinflammatory cytokines, such as NO, $PGE_2$, $TNF-{\alpha}$, IL-6, and $IL-1{\beta}$, and remarkably decreased the protein and mRNA expression of $TNF-{\alpha}$ and IL-6 in LPS-stimulated RAW 264.7 cells. TSM also suppressed protein expression of $p-I{\kappa}Ba$ and p-ERK1/2 and blocked nuclear translocation of $NF-{\kappa}B$ p65. The results indicate that TSM exerts anti-inflammatory effects related with inhibition on $NF-{\kappa}B$ and MAPK (p-ERK1/2) signaling pathways. In conclusion, our data demonstrate that TSM might be a potential agent for the treatment of ALI.

Identification of Root Age by Histochemical Staining of Secretory Duct Layers in Ginseng (인삼 분비도관의 조직화학적 염색에 의한 연근판별)

  • 이경환;이성식;이명구;김은수
    • Journal of Ginseng Research
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    • v.25 no.2
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    • pp.101-105
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    • 2001
  • Identification of the age of ginseng root is very important in commercial market as well as in research field. However, any criterion abut it has not been clearly established yet. We studied to find a clear morphological key for identification of ginseng root\\`s age using the histochemical staining method. Fresh sections of 3, 4, 5, and 6 year old roots were stained with 1% nile blue, observed under the light microscopy, and compared each other. The number of secretory duct layers(SDL) is a useful key to confirm the age of ginseng root as follow; three-year-old root has two, four-year-old one has three, fie-year-old one has four, and six-year-old one has five resin duct layers on each cortical region of roots. Secretory ducts are thought to be formed by the vascular cambium every year. Unlike the surrounding parenchyma cells, secretory epithelial cells lack starch grains in the cytoplasm.

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First Report in Korea of the Stored Grain Pest Cynaeus angustus (LeConte) and a Pictorial Identification Key for Tenebrionid Pests in Stored Products (새로운 저장곡물해충 Cynaeus angustus (LeConte) 및 저장산물의 거저리과 해충에 대한 도해검색)

  • Hong, Ki-Jeong;Yun, Tae-Sung
    • Korean journal of applied entomology
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    • v.56 no.2
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    • pp.223-227
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    • 2017
  • The larger black flour beetle, Cynaeus angustus (LeConte) (Diaperinae: Tenebrionidae) is reported for the first time in Korea. C. angustus is economically important as an insect pest in stored products in the Nearctic region, and has been identified in several rice mills in Korea. Taxonomic diagnosis and photographs presenting the morphology of adults and larvae are provided, along with a pictorial identification key to 17 tenebrionid pests detected during quarantine in stored products in Korea.

Identity-based key distribution system and conference key distribution system (ID-Based 키 분비방식 및 회의용 키 분배방식)

  • 손기욱
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.1 no.1
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    • pp.38-46
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    • 1991
  • This paper pro poses a ley distribution system based on identification information. The system uses an indivdual user's identification instead of the public file used in the Diffie-Hellman sustem. It does not require any services of a center to distribute work keys and users to keep directory public file. We propose an identity-based key distribution system for generating a commom secret conference kdy for two or more users. We assume users are connected in a ring network. Message among users authenticated using each user's identification informa-tion. The security of the our proposed system is based on the difficulty of both factoring large numbers and computing discrete logarithms over large finite fields.

A Study on Efficient Data De-Identification Method for Blockchain DID

  • Min, Youn-A
    • International Journal of Internet, Broadcasting and Communication
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    • v.13 no.2
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    • pp.60-66
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    • 2021
  • Blockchain is a technology that enables trust-based consensus and verification based on a decentralized network. Distributed ID (DID) is based on a decentralized structure, and users have the right to manage their own ID. Recently, interest in self-sovereign identity authentication is increasing. In this paper, as a method for transparent and safe sovereignty management of data, among data pseudonymization techniques for blockchain use, various methods for data encryption processing are examined. The public key technique (homomorphic encryption) has high flexibility and security because different algorithms are applied to the entire sentence for encryption and decryption. As a result, the computational efficiency decreases. The hash function method (MD5) can maintain flexibility and is higher than the security-related two-way encryption method, but there is a threat of collision. Zero-knowledge proof is based on public key encryption based on a mutual proof method, and complex formulas are applied to processes such as personal identification, key distribution, and digital signature. It requires consensus and verification process, so the operation efficiency is lowered to the level of O (logeN) ~ O(N2). In this paper, data encryption processing for blockchain DID, based on zero-knowledge proof, was proposed and a one-way encryption method considering data use range and frequency of use was proposed. Based on the content presented in the thesis, it is possible to process corrected zero-knowledge proof and to process data efficiently.

Target identification for visual tracking

  • Lee, Joon-Woong;Yun, Joo-Seop;Kweon, In-So
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.145-148
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    • 1996
  • In moving object tracking based on the visual sensory feedback, a prerequisite is to determine which feature or which object is to be tracked and then the feature or the object identification precedes the tracking. In this paper, we focus on the object identification not image feature identification. The target identification is realized by finding out corresponding line segments to the hypothesized model segments of the target. The key idea is the combination of the Mahalanobis distance with the geometrica relationship between model segments and extracted line segments. We demonstrate the robustness and feasibility of the proposed target identification algorithm by a moving vehicle identification and tracking in the video traffic surveillance system over images of a road scene.

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Automatic Identification of Business Services Using EA Ontology (EA 온톨로지 기반 비즈니스 서비스 자동 식별방안)

  • Jeong, Chan-Ki;Hwang, Sang-Kyu
    • Journal of Information Technology Services
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    • v.9 no.3
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    • pp.179-191
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    • 2010
  • Service identification and composition is one of the key characteristics for a successful Service-Oriented Computing, being receiving a lot of attention from researchers in recent years. In the Service-Oriented Analysis, the identification of business services has to be preceded before application services are identified. Most approaches addressing the derivation of business services are based on heuristic methods and human experts. The manual identification of business services is highly expensive and ambiguous task, and it may result in the service design with bad quality because of errors and misconception. Although a few of approaches of automatic service identification are proposed, most of them are in focus on technical architectures and application services. In this paper, we propose a model on the automatic identification of business services by horizontal and vertical service alignment using Enterprise Architecture as an ontology. We verify the effectiveness of the proposed model of business services identification through a case study based on Department of Defense Enterprise Architecture.

A MOM-based algorithm for moving force identification: Part II - Experiment and comparative studies

  • Yu, Ling;Chan, Tommy H.T.;Zhu, Jun-Hua
    • Structural Engineering and Mechanics
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    • v.29 no.2
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    • pp.155-169
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    • 2008
  • A MOM-based algorithm (MOMA) has been developed for moving force identification from dynamic responses of bridge in the companion paper. This paper further evaluates and investigates the properties of the developed MOMA by experiment in laboratory. A simply supported bridge model and a few vehicle models were designed and constructed in laboratory. A series of experiments have then been conducted for moving force identification. The bending moment and acceleration responses at several measurement stations of the bridge model are simultaneously measured when the model vehicle moves across the bridge deck at different speeds. In order to compare with the existing time domain method (TDM), the best method for moving force identification to date, a carefully comparative study scheme was planned and conducted, which includes considering the effect of a few main parameters, such as basis function terms, mode number involved in the identification calculation, measurement stations, executive CPU time, Nyquist fraction of digital filter, and two different solutions to the ill-posed system equation of moving force identification. It was observed that the MOMA has many good properties same as the TDM, but its CPU execution time is just less than one tenth of the TDM, which indicates an achievement in which the MOMA can be used directly for real-time analysis of moving force identification in field.

Damage detection using the improved Kullback-Leibler divergence

  • Tian, Shaohua;Chen, Xuefeng;Yang, Zhibo;He, Zhengjia;Zhang, Xingwu
    • Structural Engineering and Mechanics
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    • v.48 no.3
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    • pp.291-308
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    • 2013
  • Structural health monitoring is crucial to maintain the structural performance safely. Moreover, the Kullback-Leibler divergence (KLD) is applied usually to asset the similarity between different probability density functions in the pattern recognition. In this study, the KLD is employed to detect the damage. However the asymmetry of the KLD is a shortcoming for the damage detection, to overcoming this shortcoming, two other divergences and one statistic distribution are proposed. Then the damage identification by the KLD and its three descriptions from the symmetric point of view is investigated. In order to improve the reliability and accuracy of the four divergences, the gapped smoothing method (GSM) is adopted. On the basis of the damage index approach, the new damage index (DI) for detect damage more accurately based on the four divergences is developed. In the last, the grey relational coefficient and hypothesis test (GRCHT) is utilized to obtain the more precise damage identification results. Finally, a clear remarkable improvement can be observed. To demonstrate the feasibility and accuracy of the proposed method, examples of an isotropic beam with different damage scenarios are employed so as to check the present approaches numerically. The final results show that the developed approach successfully located the damaged region in all cases effect and accurately.