• Title/Summary/Keyword: online structural identification

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Damage detection of bridges based on spectral sub-band features and hybrid modeling of PCA and KPCA methods

  • Bisheh, Hossein Babajanian;Amiri, Gholamreza Ghodrati
    • Structural Monitoring and Maintenance
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    • v.9 no.2
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    • pp.179-200
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    • 2022
  • This paper proposes a data-driven methodology for online early damage identification under changing environmental conditions. The proposed method relies on two data analysis methods: feature-based method and hybrid principal component analysis (PCA) and kernel PCA to separate damage from environmental influences. First, spectral sub-band features, namely, spectral sub-band centroids (SSCs) and log spectral sub-band energies (LSSEs), are proposed as damage-sensitive features to extract damage information from measured structural responses. Second, hybrid modeling by integrating PCA and kernel PCA is performed on the spectral sub-band feature matrix for data normalization to extract both linear and nonlinear features for nonlinear procedure monitoring. After feature normalization, suppressing environmental effects, the control charts (Hotelling T2 and SPE statistics) is implemented to novelty detection and distinguish damage in structures. The hybrid PCA-KPCA technique is compared to KPCA by applying support vector machine (SVM) to evaluate the effectiveness of its performance in detecting damage. The proposed method is verified through numerical and full-scale studies (a Bridge Health Monitoring (BHM) Benchmark Problem and a cable-stayed bridge in China). The results demonstrate that the proposed method can detect the structural damage accurately and reduce false alarms by suppressing the effects and interference of environmental variations.

Grey algorithmic control and identification for dynamic coupling composite structures

  • ZY Chen;Ruei-yuan Wang;Yahui Meng;Timothy Chen
    • Steel and Composite Structures
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    • v.49 no.4
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    • pp.407-417
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    • 2023
  • After a disaster like the catastrophic earthquake, the government have to use rapid assessment of the condition (or damage) of bridges, buildings and other infrastructures is mandatory for rapid feedbacks, rescue and post-event management. Many domain schemes based on the measured vibration computations, including least squares estimation and neural fuzzy logic control, have been studied and found to be effective for online/offline monitoring of structural damage. Traditional strategies require all external stimulus data (input data) which have been measured available, but this may not be the generalized for all structures. In this article, a new method with unknown inputs (excitations) is provided to identify structural matrix such as stiffness, mass, damping and other nonlinear parts, unknown disturbances for example. An analytical solution is thus constructed and presented because the solution in the existing literature has not been available. The goals of this paper are towards access to adequate, safe and affordable housing and basic services, promotion of inclusive and sustainable urbanization and participation, implementation of sustainable and disaster-resilient buildings, sustainable human settlement planning and manage. Simulation results of linear and nonlinear structures show that the proposed method is able to identify structural parameters and their changes due to damage and unknown excitations. Therefore, the goal is believed to achieved in the near future by the ongoing development of AI and control theory.

Identification of the Structural Relationship between Presence, Service Quality, Flow and Learning Satisfaction in Mobile Learning (모바일러닝에서 실재감, 서비스의 질, 학습몰입 및 학습만족도 간의 구조적 관계 규명)

  • Joo, Young-Ju;Chung, Ae-Kyung;Kang, Jeong-Jin;Jung, Bo-Kyung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.4
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    • pp.169-175
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    • 2015
  • The purpose of this study is to investigate the structural relationships among teaching presence, cognitive presence, social presence, service quality, learning flow, and learners' satisfaction in mobile learning. Survey data collected by 255 learners who completed mobile-supported courses offered by an online university in South Korea were analyzed using structural equation modeling. The results suggest that cognitive presence, social presence, and service quality have direct effects on learning flow, and that cognitive presence, service quality, and learning flow have direct effects on learners' satisfaction.

The Study of a Population and Generation Parameter's Characteristics on PID Gain Tuning with GA in Wide Solution Area (넓은 해영역에서의 GA를 이용한 PID 제어기 게인 조정에 따른 개체수와 세대수 파라미터의 특징에 관한 연구)

  • Jeong, Hwang Hun
    • Journal of Power System Engineering
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    • v.21 no.3
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    • pp.60-65
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    • 2017
  • A GA is one of the best method to find optimal value in searching area. A GA is driven by probabilistic selection that based on the survival of the fittest. So this algorithm need a huge solving time even if it can be used lots of optimizing problem such as structural design, machine learning, system's identification and so on. This GA's characteristic constrain the program to drive offline. Some studies try to use this algorithm on online or reduce the GA's running time with parallel GA or micro GA. Unfortunately these studies still didn't reduce amount of fitness solving. If the chromosome was imported to the system, it affected system's stability. And when the control system uses online GA, it also doesn't have enough learning time. In this study, try to find stability criterion to reduce the chromosome's affection and find the characteristic of the number of population and generation when GA was driven into the wide searching area.

Customer-perceived distributive peer justice climate, community identification, C2C interaction quality, and helping intention in MMORPG contexts (고객의 분배공정성분위기 지각과 커뮤니티동일시, 고객간상호작용인식, 도움행동의도의 관계에 대한 연구)

  • Hyun Sik Kim
    • Journal of Service Research and Studies
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    • v.14 no.2
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    • pp.158-177
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    • 2024
  • This paper proposes and tests a theoretical model of the relational link between a novel form of customer-perceived fairness for a reward design (distributive peer justice climate) and C2C helping intention via community identification and online C2C interaction (friend-, neighboring customer-, audience-interaction) qualities in a collective consumption context (MMORPG). To test hypotheses, we amassed survey data within a collective consumption context (massively multiplayer online role-playing games, MMORPGs). We used structural equation modeling in analyzing the survey data. The results reveal that user-perceived distributive peer justice climate for a reward design enhances their C2C helping intention via community identification and C2C interactions in MMORPG contexts. Collective consumption-type service managers should focus on promoting the user-perceived distributive peer justice climate for their reward system to enhance users' present C2C co-creation experience (community identification, C2C interaction) and future C2C co-creation behavior (helping intention). By adopting an intra-unit level distributive justice concept (customer-perceived distributive peer justice climate) to a reward design in a collective consumption context (MMORPGs), this study informed collective consumption-type service managers of the importance of its management.

EvoSNP-DB: A database of genetic diversity in East Asian populations

  • Kim, Young Uk;Kim, Young Jin;Lee, Jong-Young;Park, Kiejung
    • BMB Reports
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    • v.46 no.8
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    • pp.416-421
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    • 2013
  • Genome-wide association studies (GWAS) have become popular as an approach for the identification of large numbers of phenotype-associated variants. However, differences in genetic architecture and environmental factors mean that the effect of variants can vary across populations. Understanding population genetic diversity is valuable for the investigation of possible population specific and independent effects of variants. EvoSNP-DB aims to provide information regarding genetic diversity among East Asian populations, including Chinese, Japanese, and Korean. Non-redundant SNPs (1.6 million) were genotyped in 54 Korean trios (162 samples) and were compared with 4 million SNPs from HapMap phase II populations. EvoSNP-DB provides two user interfaces for data query and visualization, and integrates scores of genetic diversity (Fst and VarLD) at the level of SNPs, genes, and chromosome regions. EvoSNP-DB is a web-based application that allows users to navigate and visualize measurements of population genetic differences in an interactive manner, and is available online at [http://biomi.cdc.go.kr/EvoSNP/].

Nonlinear intelligent control systems subjected to earthquakes by fuzzy tracking theory

  • Z.Y. Chen;Y.M. Meng;Ruei-Yuan Wang;Timothy Chen
    • Smart Structures and Systems
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    • v.33 no.4
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    • pp.291-300
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    • 2024
  • Uncertainty of the model, system delay and drive dynamics can be considered as normal uncertainties, and the main source of uncertainty in the seismic control system is related to the nature of the simulated seismic error. In this case, optimizing the management strategy for one particular seismic record will not yield the best results for another. In this article, we propose a framework for online management of active structural management systems with seismic uncertainty. For this purpose, the concept of reinforcement learning is used for online optimization of active crowd management software. The controller consists of a differential controller, an unplanned gain ratio, the gain of which is enhanced using an online reinforcement learning algorithm. In addition, the proposed controller includes a dynamic status forecaster to solve the delay problem. To evaluate the performance of the proposed controllers, thousands of ground motion data sets were processed and grouped according to their spectrum using fuzzy clustering techniques with spatial hazard estimation. Finally, the controller is implemented in a laboratory scale configuration and its operation is simulated on a vibration table using cluster location and some actual seismic data. The test results show that the proposed controller effectively withstands strong seismic interference with delay. The goals of this paper are towards access to adequate, safe and affordable housing and basic services, promotion of inclusive and sustainable urbanization and participation, implementation of sustainable and disaster-resilient buildings, sustainable human settlement planning and manage. Simulation results is believed to achieved in the near future by the ongoing development of AI and control theory.

Antecedents of Intent to Purchase a Brand Extension -A University-Licensed Merchandise Case-

  • Lee, Jaeha;Park, Kwangsoo
    • Journal of Fashion Business
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    • v.22 no.3
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    • pp.1-15
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    • 2018
  • The purpose of this study is to address marketing strategies for the brand extension of university-licensed merchandise by investigating influences on intent to purchase a new university-licensed merchandise line, tartan. A survey questionnaire was developed and administered online to the major target market for university-licensed merchandise. Four hundred and fifty students and alumni from a US Midwestern university completed the survey. Respondents were asked to answer questions on university identification, perceived university prestige, perceived value of the university-licensed merchandise, intent to purchase a brand extension in university-licensed merchandise, and demographics. It was hypothesized that university identification (H1) and perceived university prestige (H2) are positively related to the perceived value of the university-licensed merchandise and that perceived value of the university-licensed merchandise is positively related to intent to purchase a brand extension in university-licensed merchandise (H3). The difference between students and alumni was also tested. Consumers with high university identification and high perceived university prestige highly valued the university-licensed merchandise. Consumers who perceived a high value of the current university-licensed merchandise displayed a strong intent to purchase a brand extension in university-licensed merchandise. There was no structural difference between the two groups. The study builds on existing research on the influences of attitudes toward the university and university-licensed merchandise on purchasing university-licensed merchandise, specifically investigating intent to purchase a brand extension in university-licensed merchandise. This study also extends previous brand-extension research into university-licensed merchandise.

The Influence of Transformational Leadership on Unethical Pro-Organizational Behavior-Mediating Effect of Organizational Identification (변혁적 리더십이 비윤리적 친조직 행동에 미치는 영향 -조직 동일시의 매개 효과)

  • Lee, Kang-Min;Choo, Shi-Gak;Jeon, Sang-Gil
    • Journal of Digital Convergence
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    • v.14 no.2
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    • pp.83-98
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    • 2016
  • This study attempted to test not only the influence of transformational leadership(TFL) on employees' unethical pro-organizational behavior(UPB), but also the mediating effect of organizational identification(OID) between TFL and employees' UPB. This study employed two research methods: literature review and empirical testing of the developed hypotheses. Data were collected through online questionnaire instruments from 229 employees working at companies in Korea. To test the hypotheses, structural equation modeling was employed. The model is shown as adequately fitting to the data. The results showed that there was not a positive and statistically significant relationship between TFL and employees' UPB, and OID played as a mediator in the relationship between TFL and employees' UPB. These findings provide a meaningful implication that the positive impact of TFL is linked to employees' UPB through OID.

The Research on Online Game Hedonic Experience - Focusing on Moderate Effect of Perceived Complexity - (온라인 게임에서의 쾌락적 경험에 관한 연구 - 지각된 복잡성의 조절효과를 중심으로 -)

  • Lee, Jong-Ho;Jung, Yun-Hee
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.2
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    • pp.147-187
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    • 2008
  • Online game researchers focus on the flow and factors influencing flow. Flow is conceptualized as an optimal experience state and useful explaining game experience in online. Many game studies focused on the customer loyalty and flow in playing online game, In showing specific game experience, however, it doesn't examine multidimensional experience process. Flow is not construct which show absorbing process, but construct which show absorbing result. Hence, Flow is not adequate to examine multidimensional experience of games. Online game is included in hedonic consumption. Hedonic consumption is a relatively new field of study in consumer research and it explores the consumption experience as a experiential view(Hirschman and Holbrook 1982). Hedonic consumption explores the consumption experience not as an information processing event but from a phenomenological of experiential view, which is a primarily subjective state. It includes various playful leisure activities, sensory pleasures, daydreams, esthetic enjoyment, and emotional responses. In online game experience, therefore, it is right to access through a experiential view of hedonic consumption. The objective of this paper was to make up for lacks in our understanding of online game experience by developing a framework for better insight into the hedonic experience of online game. We developed this framework by integrating and extending existing research in marketing, online game and hedonic responses. We then discussed several expectations for this framework. We concluded by discussing the results of this study, providing general recommendation and directions for future research. In hedonic response research, Lacher's research(1994)and Jongho lee and Yunhee Jung' research (2005;2006) has served as a fundamental starting point of our research. A common element in this extended research is the repeated identification of the four hedonic responses: sensory response, imaginal response, emotional response, analytic response. The validity of these four constructs finds in research of music(Lacher 1994) and movie(Jongho lee and Yunhee Jung' research 2005;2006). But, previous research on hedonic response didn't show that constructs of hedonic response have cause-effect relation. Also, although hedonic response enable to different by stimulus properties. effects of stimulus properties is not showed. To fill this gap, while largely based on Lacher(1994)' research and Jongho Lee and Yunhee Jung(2005, 2006)' research, we made several important adaptation with the primary goal of bringing the model into online game and compensating lacks of previous research. We maintained the same construct proposed by Lacher et al.(1994), with four constructs of hedonic response:sensory response, imaginal response, emotional response, analytical response. In this study, the sensory response is typified by some physical movement(Yingling 1962), the imaginal response is typified by images, memories, or situations that game evokes(Myers 1914), and the emotional response represents the feelings one experiences when playing game, such as pleasure, arousal, dominance, finally, the analytical response is that game player engaged in cognition seeking while playing game(Myers 1912). However, this paper has several important differences. We attempted to suggest multi-dimensional experience process in online game and cause-effect relation among hedonic responses. Also, We investigated moderate effects of perceived complexity. Previous studies about hedonic responses didn't show influences of stimulus properties. According to Berlyne's theory(1960, 1974) of aesthetic response, perceived complexity is a important construct because it effects pleasure. Pleasure in response to an object will increase with increased complexity, to an optimal level. After that, with increased complexity, pleasure begins with a linearly increasing line for complexity. Therefore, We expected this perceived complexity will influence hedonic response in game experience. We discussed the rationale for these suggested changes, the assumptions of the resulting framework, and developed some expectations based on its application in Online game context. In the first stage of methodology, questions were developed to measure the constructs. We constructed a survey measuring our theoretical constructs based on a combination of sources, including Yingling(1962), Hargreaves(1962), Lacher (1994), Jongho Lee and Yunhee Jung(2005, 2006), Mehrabian and Russell(1974), Pucely et al(1987). Based on comments received in the pretest, we made several revisions to arrive at our final survey. We investigated the proposed framework through a convenience sample, where participation in a self-report survey was solicited from various respondents having different knowledges. All respondents participated to different degrees, in these habitually practiced activities and received no compensation for their participation. Questionnaires were distributed to graduates and we used 381 completed questionnaires to analysis. The sample consisted of more men(n=225) than women(n=156). In measure, the study used multi-item scales based previous study. We analyze the data using structural equation modeling(LISREL-VIII; Joreskog and Sorbom 1993). First, we used the entire sample(n=381) to refine the measures and test their convergent and discriminant validity. The evidence from both the factor analysis and the analysis of reliability provides support that the scales exhibit internal consistency and construct validity. Second, we test the hypothesized structural model. And, we divided the sample into two different complexity group and analyze the hypothesized structural model of each group. The analysis suggest that hedonic response plays different roles from hypothesized in our study. The results indicate that hedonic response-sensory response, imaginal response, emotional response, analytical response- are related positively to respondents' level of game satisfaction. And game satisfaction is related to higher levels of game loyalty. Additionally, we found that perceived complexity is important to online game experience. Our results suggest that importance of each hedonic response different by perceived game complexity. Understanding the role of perceived complexity in hedonic response enables to have a better understanding of underlying mechanisms at game experience. If game has high complexity, analytical response become important response. So game producers or marketers have to consider more cognitive stimulus. Controversy, if game has low complexity, sensorial response respectively become important. Finally, we discussed several limitations of our study and suggested directions for future research. we concluded with a discussion of managerial implications. Our study provides managers with a basis for game strategies.

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