• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.9
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• pp.2314-2333
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• 2023

It is significant to predict the performance degradation of complex electromechanical systems. Among the existing performance degradation prediction models, belief rule base (BRB) is a model that deal with quantitative data and qualitative information with uncertainty. However, when analyzing dynamic systems where observable indicators change frequently over time and working conditions, the traditional belief rule base (BRB) can not adapt to frequent changes in working conditions, such as the prediction of aeroengine performance degradation considering working condition. For the sake of settling this problem, this paper puts forward a new hidden belief rule base (HBRB) prediction method, in which the performance of aeroengines is regarded as hidden behavior, and operating conditions are used as observable indicators of the HBRB model to describe the hidden behavior to solve the problem of performance degradation prediction under different times and operating conditions. The performance degradation prediction case study of turbofan aeroengine simulation experiments proves the advantages of HBRB model, and the results testify the effectiveness and practicability of this method. Furthermore, it is compared with other advanced forecasting methods. The results testify this model can generate better predictions in aspects of accuracy and interpretability.

• Journal of the Korea Safety Management & Science
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• v.9 no.3
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• pp.135-142
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• 2007

The authors used association rules and patterns in sequential of data mining in order to raise the efficiency of engineering changes. The association rule can reduce the number of engineering changes since it can estimate the parts to be changed. The patterns in sequential can perform engineering changes effectively by estimating the parts to be changed from sequence estimation. According to this result, unnecessary engineering changes are eliminated and the number of engineering changes decrease. This method can be used for improving design quality and productivity in company managing engineering changes and related information.

• The Journal of Society for e-Business Studies
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• v.12 no.1
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• pp.99-122
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• 2007

The rule based system is inference engine which can correspond quickly to new business model change and improvement requirement by dealing with the business know-how and expert knowledge as well as business process of enterprise and has been trying to apply to the various industries. As a part of application cases for rule-based system, we develop and implement the rule-based insurance product recommend and design system for the efficient decision making of insurance product in insurance industry which is sensitively affected by needs of customers, various kinds of product, and environment changes. The process of fuzzy inference of the developed system helps to recommend and design the proper Insurance product using the information of the present customer and the previous members. This approach is expected that it will be the core technology for the recommendation and design of the tailored insurance product by deciding and corresponding needs of various kinds of customer quickly in future insurance industry.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.5
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• pp.9-17
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• 2012

Merchandise recommendations service based on electronic commerce has been actively studied and on service these days. By virtue of progress in IT industry, POS has been widely used even in small shops, but the merchandise recommendations service using POS has not been much facilitated compared with that of using electronic commerce. This paper proposes a merchandise recommendations service system using association analysis by applying data mining algorithm to POS sales data. This paper, also, suggests novel services such as annihilation rule and new rule, and ascending and descending rules. The analysis results are applied to the customers enabling to offer merchandise recommendations service. In addition, prompt responses against the changes in demands from customers are possible by identifying the annihilation rule and new rule, and ascending and descending rules, and providing the management with the rules as managerial decision making information.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.3
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• pp.265-274
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• 2015

International organizations and classification societies established rules and regulations to which shipbuilders and ship operators should comply during design, construction, even operation keeping from hazard to life of crews and ocean environment. Hence, rules and regulations could be guidelines for design and construction of ship sometimes. In practical wise, ship structure designers be predisposed to design lightest and easy-to-product structures which satisfy rules and regulations. Therefore, changes of rules and regulations are remarkably important issue to related industries. In 2006, IACS established and released Common Structural Rules for Bulk Carrier and Common Structural Rules for Double Hull Oil Tanker. These CSRs are consolidated and unified rules of class society's rules. But these two rules are different from each other. IACS has plan to release unified rule of two ship type called Harmonized Common Structural Rule for Bulk Carriers and Oil Tankers. This new rule will be effective from July 2015. Hence, bulk carrier and double hull oil tanker whose contract date is on and thereafter July 2015 should be complied with CSR-H. Therefore, it is highly important to be aware of consequences and cause of consequences with respect to CSR-H. The object of this research is to compare requirements of structure scantling in way of midship area for selected target ship according to CSRs and CSR-H and to analysis cause of deviation between two rules.

• Journal of the Korean Society for information Management
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• v.20 no.1
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• pp.251-270
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• 2003

Due to rapid internet supply and the increase of electronic resources including network resources, there has been a sudden change in cataloguing fields. To deal with rapid changes, IFLA revised cataloguing rules for electronic and continuing resources; ISBD(ER) and ISBD(CR), JSC(Joint Steering Committee for Revision of AACR) has published the 2002 revision of Anglo-American Cataloguing Rules, Second Edition. Major changes in both content and format make the release of the 2002 revision momentous. This study is to analyze activities of JSC and rule revisions of AACR2R 2002 edition, expecially in regards with concepts of change to rule 0.24, new categories of bibliographic materials, changes to chapter 3(cartographic materials), chapter 9(electronic materials), chapter 12(continuing materials), definition of a new terminologies, changes in MARC 21 coding, and issues concerned with revision of KORMARC.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.232-232
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• 2015

Land use and climate changes are the important factors to determine the runoff and sediment loads from the watershed. The changes also affected to runoff volume/pattern to the dam operation and may cause flood and drought situations in the downstream area. Sirikit Dam is one of the biggest dams in Thailand which cover about 25 % of the runoff into the Central Plain where the Bangkok Capital is located. The study aims to determine the effect of land use change to the runoff/sediment volume pattern and the rainfall-runoff-sediment relationship in the different land use type. Field measurements of the actual rainfall, runoff and sediment in the selected four sub-basins with different type of land use in the Upper Nan Basin were conducted and the runoff ratio coefficients and sediment yield were estimated for each sub-basin. The effect of the land use change (deforestation) towards runoff/sediment will be investigated. The study of the climate change impact on the runoff in the future scenarios was conducted to project the change of runoff volume/pattern into the Sirikit Dam. The improvement of the Sirikit Dam operation rule was conducted to reduce the weakness of the existing operation rules after Floods 2011. The newly proposed dam operation rule improvement will then be evaluated from the water shortage situations in the downstream of Sirikit Dam under various conditions of changes of both land use and climate when compared with the situations based on the existing reservoir operation rules.

• Journal of the Korea Convergence Society
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• v.10 no.2
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• pp.217-225
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• 2019

The Latent Growth Modeling(LGM) is known as the typical analysis method of longitudinal data and it could be classified into unconditional model and conditional model. It is common to assume that the growth trajectory of unconditional model of LGM is linear. In the case of quasi-linear, the methodology for improving the model fitness using Sequential Pattern of Association Rule Mining is suggested. To do this, we divide longitudinal data into quintiles and extract periodic changes of the longitudinal data in each quintiles and make sequential pattern based on this periodic changes. To evaluate the effectiveness, the LGM module in SPSS AMOS was used and the dataset of the Youth Panel from 2001 to 2006 of Korea Employment Information Service. Our methodology was able to increase the fitness of the model compared to the simple linear growth trajectory.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.143-153
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• 1997

At the on-line control method FLC(Fuzzy Logic Controller) is stronger to the disturbance than a classical controller and its overshoot of the initialized value is excellent. The fuzzy controller can do a proper control, though it doesn't know the mathematical model of the system or the parameter value. But to make the control rule of the fuzzy controller through an expert's experiance has a changes of the control system, the control rule is fixed, it can't adjust to the environment changes of the control system, the controller output value has a minute error and it can't convergence correctly to the desired value[1][2]. There are many ways to eliminate the minute error[3][4][5], but in this paper suggests EP-FNNIC(Fuzzy Neurla Network Intelligence Controller) intelligence controller which combines FLC with NN(Neural Network) and EP(Evolution Programming). The output characteristics of EP-FNNIC controller will be compared and analyzed with FLC. It will be showed that this EP-FN IC controller converge correctly to the desirable value without any error. The convergence speed, overshoot, rising time, error of steady state of controller of these two kinds also will be compared.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.395-402
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• 2006

In analyzing the nano-scale phenomena or behaviors of nano devices or materials, it is often desirable to deal with more atoms than can be treated only with a full atomistic simulation. However, even now, it is advisable to apply the atomistic simulation to the narrow region where the deformation field changes rapidly but to apply the conventional continuum model to the region far from that region. This equivalent continuum model can be formulated by applying the Cauchy-Born rule to the exact atomistic potential as in the quasicontinuum method. To couple the atomistic model with the equivalent continuum model, continuum displacements are conformed to the molecular displacements at the discrete positions of the atoms within the bridging domain. To satisfy the coupling constraints, we apply the Lagrange multiplier method. The continuum model in the bridging model should be applied on the region where the deformation field changes gradually. Then we can make the nodal spacing in the continuum model be much larger than the atomic spacing. In the first step, we generate the atomic-resolution mesh with the nodal spacing equal to the atomic spacing, and then we eliminate the nodal degrees of freedom adaptively using the node deactivation techniques. We eliminate more DOFs as the regions are more far from the atomistic region. Computing time and computational resources can be greatly reduced by the present node deactivation technique in multi scale analysis.