• Title/Summary/Keyword: Context Uncertainty

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Probabilistic sensitivity of base-isolated buildings to uncertainties

  • Gazi, Hatice;Alhan, Cenk
    • Smart Structures and Systems
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    • v.22 no.4
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    • pp.441-457
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    • 2018
  • Characteristic parameter values of seismic isolators deviate from their nominal design values due to uncertainties and/or errors in their material properties and element dimensions, etc. Deviations may increase over service life due to environmental effects and service conditions. For accurate evaluation of the seismic safety level, all such effects, which would result in deviations in the structural response, need to be taken into account. In this study, the sensitivity of the probability of failure of the structures equipped with nonlinear base isolation systems to the uncertainties in various isolation system characteristic parameters is investigated in terms of various isolation system and superstructure response parameters in the context of a realistic three-dimensional base-isolated building model via Monte Carlo Simulations. The inherent record-to-record variability nature of the earthquake ground motions is also taken into account by carrying out analyses for a large number of ground motion records which are classified as those with and without forward-directivity effects. Two levels of nominal isolation periods each with three different levels of uncertainty are considered. Comparative plots of cumulative distribution functions and related statistical evaluation presented here portray the potential extent of the deviation of the structural response parameters resulting from the uncertainties and the uncertainty levels considered, which is expected to be useful for practicing engineers in evaluating isolator test results for their projects.

The Effects of RMO and PMO on SMEs' New Product Performance: The Moderating Role of Foreign Market Environment (반응적시장지향성과 선제적시장지향성이 중소기업의 신제품 성과에 미치는 영향: 수출시장환경의 조절효과를 중심으로)

  • Lee, Youngwoo;Cho, Hyo Eun;Jeong, Insik
    • Knowledge Management Research
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    • v.20 no.1
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    • pp.175-194
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    • 2019
  • In order to overcome the limitation of market orientation concept, Narver et al. (2004) have extended the original concept into two dimensions, responsive market orientation (RMO) and proactive market orientation (PMO), respectively. Yet, there has been very limited empirical studies that analyzed the differential effects of each market orientation on firm outcomes, especially in the Korean context. We analyze the impact of RMO and PMO on the new product performance in the perspective of SMEs and examine the moderating effect of external factors such as environmental uncertainty and market similarity. The results of this study show that both RMO and PMO have a significant positive effect on the new product performance of SMEs. Also, environment uncertainty shows a negative moderating effect on the relationship between RMO and new product performance, whereas it has positive moderation with PMO. This suggests that focusing on potential customers' needs rather than current needs helps improve firm performance as the competitive environment surrounding the firm becomes more uncertain. Lastly, market similarity showed a positive moderating effect on the relationship between RMO and new product performance, but not on PMO.

THE OVERPAYMENT IN MULTIPLE BIDDING (기업합병: 다수경쟁에서의 과잉지분에 대한 연구)

  • Lee, You-Tay
    • The Korean Journal of Financial Management
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    • v.14 no.3
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    • pp.319-339
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    • 1997
  • This paper provides an empirical analysis of the winner's curse in the context of corporate takeovers. The study analyzes conditions which make overpayment likely. For a sample of corporate takeovers completed between 1982 and 1993, the analysis shows that the volatility of targets relative to that of acquirers (not the uncertainty of the target or acquirer alone) has a definitive impact on the magnitude of the winner's curse. Also, the incidence is more pronounced in multiple-bidder than in single-bidder contests. Specifically, white knights are more likely to overpay than other acquirers in multiple bidding situations. Furthermore, the study finds that the process of competitive bidding is a zero sum game since the greater returns to the shareholders of target firms in multiple-bid contests come at the expense of the acquiring companies, Overall, the evidence suggests that the bidders need to become more conservative, particularly as the relative uncertainty of the target's 'true' value and the number of bidders increase.

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Robust H(sup)$\infty$ FIR Sampled-Data Filtering for Uncertain Time-Varying Systems with Lipschitz Nonlinearity

  • Ryu, Hee-Seob;Yoo, Kyung-Sang;Kwon, Oh-Kyu
    • Transactions on Control, Automation and Systems Engineering
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    • v.2 no.4
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    • pp.255-261
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    • 2000
  • This paper presents the results of the robust H(sub)$\infty$ FIR filtering for a class of nonlinear continuous time-varying systems subject to real norm-bounded parameter uncertainty and know Lipschitz nonlinearity under sampled measurements. We address the problem of designing filters, using sampled measurements, which guarantee a prescribed H(sub)$\infty$ performance in continuous time-varying context, irrespective of the parameter uncertainty and unknown initial states. The infinite horizon causal H(sub)$\infty$FIR filter are investigated using the finite moving horizon in terms of two Riccati equations with finite discrete jumps.

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Bootstrap simulation for quantification of uncertainty in risk assessment

  • Chang, Ki-Yoon;Hong, Ki-Ok;Pak, Son-Il
    • Korean Journal of Veterinary Research
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    • v.47 no.2
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    • pp.259-263
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    • 2007
  • The choice of input distribution in quantitative risk assessments modeling is of great importance to get unbiased overall estimates, although it is difficult to characterize them in situations where data available are too sparse or small. The present study is particularly concerned with accommodation of uncertainties commonly encountered in the practice of modeling. The authors applied parametric and non-parametric bootstrap simulation methods which consist of re-sampling with replacement, in together with the classical Student-t statistics based on the normal distribution. The implications of these methods were demonstrated through an empirical analysis of trade volume from the amount of chicken and pork meat imported to Korea during the period of 1998-2005. The results of bootstrap method were comparable to the classical techniques, indicating that bootstrap can be an alternative approach in a specific context of trade volume. We also illustrated on what extent the bias corrected and accelerated non-parametric bootstrap method produces different estimate of interest, as compared by non-parametric bootstrap method.

Simulation-Based Assessment of Seismic Slope Stability (시뮬레이션 기법을 이용한 지진 시 사면안정 해석)

  • 김진만
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.03a
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    • pp.157-164
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    • 2003
  • A simulation-based approach that can be used to systematically model the uncertainties of seismic loading and geotechnical property is presented in the context of reliability analysis of slope stability. The uncertainty of seismic loading is studied by generating a large series of hazard-compatible artificial motions, and by using them in subsequent response analyses. The stochastic nature of spatially varying material properties and also the uncertainty arising from insufficient information are treated in the framework of random fields. The simulation-based analyses indicate that in a seismically less active region, a moderate variability in soil properties has a relatively large effect as much as characterization of earthquake hazard on the computed risk of slope failure and excessive slope deformations.

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INVESTMENT EVALUATION OF TRANSPORTATION INFRASTRUTURE PROJECTS USING BINOMIAL REAL OPTION MODEL

  • Qiyu Qian;Xueqing Wang;Charles Y.J. Cheah
    • International conference on construction engineering and project management
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    • 2007.03a
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    • pp.563-572
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    • 2007
  • Transportation infrastructure is critical to economic growth of a country such as China. Careful evaluation of investments in traffic infrastructure projects is therefore pertinent. As traditional evaluation methods do not consider the uncertainty of future cash flows and mobility during project execution, the real option approach is gradually gaining recognition in the context of valuing construction and infrastructure projects. However, many of the cases only evaluate individual options separately although multiple options often exist in a typical large infrastructure project. Using a highway project in China as a case study, this paper first evaluates a deferment option and a growth option embedded in the project. Subsequently, the values are combined using the fuzzy analytical hierarchy process. It is found that the combined value is less than the sum of the two option values. This finding is consistent with the theoretical observations given in past real option literature despite the use of a different approach.

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Object Recognition for Mobile Robot using Context-based Bi-directional Reasoning (상황 정보 기반 양방향 추론 방법을 이용한 이동 로봇의 물체 인식)

  • Lim, G.H.;Ryu, G.G.;Suh, I.H.;Kim, J.B.;Zhang, G.X.;Kang, J.H.;Park, M.K.
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.6-8
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    • 2007
  • In this paper, We propose reasoning system for object recognition and space classification using not only visual features but also contextual information. It is necessary to perceive object and classify space in real environments for mobile robot. especially vision based. Several visual features such as texture, SIFT. color are used for object recognition. Because of sensor uncertainty and object occlusion. there are many difficulties in vision-based perception. To show the validities of our reasoning system. experimental results will be illustrated. where object and space are inferred by bi -directional rules even with partial and uncertain information. And the system is combined with top-down and bottom-up approach.

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Oral Health Diagnosis by Using Combination of Evidence in Dezert-Smarandache Theory

  • Fadhillah, Muhammad Kamil;Listio, Syntia;Choi, Yong Keum;Lee, Hyun
    • International journal of advanced smart convergence
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    • v.7 no.4
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    • pp.185-196
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    • 2018
  • Based on World Health Organization (WHO) children and adults have a problem with their oral health, such as Dental cavities and periodontal disease. It is not easy to obtain the high convince level of result of the dental and periodontal diseases. Because each of them have different degrees of uncertainty and there have several discounting factors (error rates) in different of survey. To solve this problem we propose the Dezert-Smarandache Theory (DSmT) for efficient combination of uncertain, imprecise and highly conflicting sources of information. Moreover, we apply the SEFP as a context reasoning. Finally, we make the simulation by using 12 surveys and compare Propotional Conflict Redistribution 5 (PCR5) and Dempster-Shafer Theory (DST) to show the belief or probability for the low, a heavy, high and ultra-high risk situation.

Decolonized Participatory Communication: A Study of Community Business in Rural Thai Community

  • Kittima Chanvichai
    • Journal of Contemporary Eastern Asia
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    • v.23 no.2
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    • pp.35-51
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    • 2024
  • Participatory communication is a Western concept that emphasizes equal participation among stakeholders. However, in the context of rural Thai communities, where hierarchy and respect for social status are deeply ingrained, equal participation in communication is not the norm. This article examines the implementation of participatory communication in rural Thai communities through interviews and observations of local banana processing entrepreneurs in Phitsanulok province, Thailand. The findings indicate that within a culture characterized by high-context communication, high power distance, and high uncertainty avoidance - elements fundamentally at odds with the concept of equal participation in 'participatory communication'-Thai local entrepreneurs successfully operate their businesses in harmony and peace. This article, therefore, calls for the decolonization of the Western concept of participatory communication by promoting a deeper understanding of local contexts that reflect cultural and value systems distinct from those in which the concept originated. This approach aims to foster genuine equal opportunities in knowledge creation within the communication discipline, benefiting both scholars and practitioners.