• Journal of the Korean Society for Railway
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• v.20 no.4
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• pp.474-481
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• 2017

When designing photovoltaic power plants in Korea, the prediction of photovoltaic power generation at the design phase is carried out using PVSyst, PVWatts (Overseas power generation prediction software), and overseas weather data even if the test site is a domestic site. In this paper, for a comparative study to predict power generation using weather information, domestic photovoltaic power plants in two regions were selected as target sites. PVsyst, which is a commercial power generation forecasting program, was used to compare the accuracy between the predicted value of power generation (obtained using overseas weather information (Meteonorm 7.1, NASA-SSE)) and the predicted value of power generation obtained by the Korea Meteorological Administration (KMA). In addition, we have studied ways to improve the prediction of power generation through comparative analysis of meteorological data. Finally, we proposed a revised solar power generation prediction model that considers climatic factors by considering the actual generation amount.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1364-1366
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• 2002

The Photovoltaic(PV) generation system is a promising source of energy for the future. Since the need for renewable energy has been increased, the research of PV generation system has also been progressed. Recently, cost down of PV generation system has been accomplished and practical technologies of the solar energy developed, Moreover, grid connected PV generation system are becoming actual and general. Operational technology of the grid connected PV generation system is being a hot issue. Power output of PV system is directly affected by wether conditions. When AC power supply is needed, power conversion by an inverter and a MPPT control are necessary. In this paper, for stability improvement of PV generation system. Active filter(AF) function is added to PV generation system, and simulations of PV-AF system under various weather conditions are performed.

• Korean Journal of Computational Design and Engineering
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• v.1 no.1
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• pp.65-75
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• 1996

This paper describes an automatic finite element(FE) mesh generation for three-dimensional structures consisting of free-form surfaces. This mesh generation process consists of three subprocesses: (a) definition of geometric model, i.e. analysis model, (b) generation of nodes, and (c) generation of elements. One of commercial solid modelers is employed for three-dimensional solid and shell structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay method is introduced as a basic tool for element generation. Automatic generation of FE meshes for three-dimensional solid and shell structures holds great benefits for analyses. Practical performances of the present system are demonstrated through several mesh generations for three-dimensional complex geometry.

• Korean Journal of Computational Design and Engineering
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• v.18 no.2
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• pp.104-112
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• 2013

Computer-based modeling and simulation (M&S) techniques have become an essential component in the development of new weapons systems. M&S techniques provide a means to simulate military training, strategies, military doctrines, and weapons acquisition processes. This paper proposes a small scale engagement scenario generation method. This work also includes a process for scenario generation and visualization. The proposed scenario generation methodology employs the Timed-FSA (finite state automata) and DFS (depth first search) algorithms. The proposed scenario generation method is verified using a one-on-one combat engagement scenario between two submarines. In addition, we suggest a scenario generation process including whole scenario generation and scenario visualization.

• Phonetics and Speech Sciences
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• v.10 no.1
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• pp.49-55
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• 2018

This paper aims to describe a knowledge-based pronunciation generation system for French. It has been reported that a rule-based pronunciation generation system outperforms most of the data-driven ones for French; however, only a few related studies are available due to existing language barriers. We provide basic information about the French language from the point of view of the relationship between orthography and pronunciation, and then describe our knowledge-based pronunciation generation system, which consists of morphological analysis, Part-of-Speech (POS) tagging, grapheme-to-phoneme generation, and phone-to-phone generation. The evaluation results show that the word error rate of POS tagging, based on a sample of 1,000 sentences, is 10.70% and that of phoneme generation, using 130,883 entries, is 2.70%. This study is expected to contribute to the development and evaluation of speech synthesis or speech recognition systems for French.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.9
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• pp.78-83
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• 2006

A new measure, the distributed generation impact factor (DGIF), is used for evaluating the impact of newly introduced distributed generators on a networked distribution or a transmission system. Distribution systems are normally operated in a radial structure. But the introduction of distributed generation needs load flow calculation to analyze the networked system. In the developed framework, the potential share of every generation bus in each line flow of a networked system can be directly evaluated. The developed index does not require the solution of power flow equations to evaluate the effect of the distributed generation. The main advantage of the developed method lies in its capability of considering simultaneous outputs of multiple generation sites.

• Korean Journal of Computational Design and Engineering
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• v.5 no.1
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• pp.95-101
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• 2000

For last two decades numerous automatic mesh generation algorithms for various two dimensional objects have been introduced continuously and among them triangular mesh generation schemes have been majority because of efficiency and controllability. In our study, an existing triangular mesh generation algorithm developed by Lo is totally modified to more improve node distribution, element shape, and objects shape independency. ft is composed of node generation part and element generation part. In order to find a suitable node position within geometry, the suggested algorithm searches desirable positions of points within boundary and optimizes node position to generate comparatively well-shaped elements. More over, the suggested algorithm handles various complex two dimensional objects and its meshing speed shows superiority to those of the existing triangulation mesh generation algorithms. It is fully automated in a sense of constructing object boundary and hence can be directly used as an independent meshing software.

• Journal of the Korean Home Economics Association
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• v.36 no.10
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• pp.145-160
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• 1998

The purposes of this research were to find out general trends of family value orientations among adolescent, middle and old generation and to investigate the differences according to related variables. For this study, three kinds of questionnaire were used and the data were obtained through 1194 samples of three generation groups living in Seoul and Kwangju. The traditional trends of old generation's value orientations were outstanding while adolescents relatively showed modernized value orientations. The value differences between adolescent and middle generation were larger than between middle and old generation. Especially value orientations of children and sex-role were largely changed, but familism was relatively preserved even in adolescent generation. The family value orientations differed significantly according to gender, age, eduaction level, income, occupation, and family type. Generally middle and adolescent women showed more modernized value orientatons than men and value orientations of three generation were most likely to be correlated with family satisfaction level.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.4
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• pp.305-312
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• 2014

This paper discusses real-time peak shaving algorithms for a large-scale battery energy storage system (BESS). Although several transmission and distribution functions could be implemented for diverse purposes in BESS applications, this paper focuses on a real-time peak shaving algorithm for an energy time shift, considering wind power generation. In a high wind penetration environment, the effective load levels obtained by subtracting the wind generation from the load time series at each long-term cycle time unit are needed for efficient peak shaving. However, errors can exist in the forecast load and wind generation levels, and the real-time peak shaving operation might require a method for wind generation that includes comparatively large forecasting errors. To effectively deal with the errors of wind generation forecasting, this paper proposes a real-time peak shaving algorithm for threshold value-based peak shaving that considers fuzzy wind power generation.

• 연구논문집
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• s.31
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• pp.45-51
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• 2001

One of emerging technologies under development in the advanced countries is considered as RDF(Refuse Derived Fuel) power generation, which could meet both the requirement of an alternative energy resource utilization and $CO_2$ reduction. This paper deals with the effect to the thermal effiency and CO2 reduction of RDF firing power generation. The statistical data of domestic MSW generation in last year in small and medium cities for evaluating the merits of the RDF power generation were used. The analysis for RDF power generation compared to the existing incinerator w/o(or w/) power generation shows around 20.6%(10.0%) up in the total thermal efficiency and 57.0%(31.4%) up in the $CO_2$ reduction respectively.