• KIEE International Transactions on Power Engineering
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• v.5A no.1
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• pp.79-84
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• 2005

In many countries, the electric power industry is undergoing significant changes known as deregulation and restructuring. These alterations introduce competition in generation and retail and require open access to the transmission network. The competition of the electric power industry causes many issues to surface. Among them, unbundling of the transmission service is probably the most complicated as it is a single and integrated sector and the transmission revenue requirement must be allocated to market participants in a fair way. In these situations, it is valuable to research the methodologies to allocate transmission usage. The power tracing method offers useful information such as which generators supply a particular load or how much each generator (load) uses a particular transmission line. With this information, we can allocate required transmission revenue to market participants. Recently, several algorithms were proposed for tracing power flow but there is no dominant power tracing method. This paper proposes a power tracing method based on graph theory and complex-current distribution. For practicability, the proposed method for transmission usage allocation is applied to IEEE 30 buses and compared with the method proposed by Felix F.Wu.

• The KIPS Transactions:PartA
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• v.12A no.2 s.92
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• pp.145-150
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• 2005

Recently, many Processor manufacturers have implemented simultaneous multi treading technology, which can simultaneously execute independent threads in one processor cycle, as a way of increasing processor efficiency, ana one particular example is Hyper Threading. Hyper Threading technology, which enables many logical processors to reside a physical processor, differs from the current multiprocessing environment which has many independent processors, and calls for a particular work assignment method optimized for Hyper Threading environment Thus, in this paper, We have proposed a scheduling algorithm compatible with Hyper Threading technology and analyzed its performance using various methods. As a result, we shall expect its efficient performance by properly understanding and managing Hyper Threading system.

• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.87-96
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• 2016

More than half of Korea's urban population currently lives in multi-unit dwellings. This particular residence structure inevitably positions the living spaces of residents in close proximity to one another. Because of this proximity, the sounds of a particular household will transfer to other residents' units creating conflict between tenants. Efforts to alleviate this problem have been made in both the public and private sector. A prominent method of noise analysis between living units has been to make an actual sound measurement and obtain qualitative measurements from questionnaires. Although this method has been most widely used, such analysis requires a large amount of human effort and time. In addition, the questionnaire method fails to provide the objective information needed to accurately assess the noise situation. To overcome the inadequacies of this previous method, this study seeks to evaluate the applicability of an acoustic simulation method. Three types of living noises were analyzed to assess the noise levels passed between multi-unit dwellings. The acoustic simulation method was found to be more economical, efficient, and adaptable in information processing. The results of this study can be further applied to design and control living-noise through procedures such as acoustic absorption or space redesign.

• Journal of the Korean association of regional geographers
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• v.22 no.2
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• pp.287-306
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• 2016

This paper aims to explain the Korean urbanization, which can be characterized by the development of apartment complexes and new towns, in relation to urban ideology in Korea. In particular, it examines the impacts of the ideological processes of Gangnam-ization on the ways in which 'the urban' has been represented, imagined, aspired, and consumed by the Korean urban middle class in particular ways. For this research, we interviewed 22 urban middle class people living in three important urban centers (Gangnam, Bundang, and Haeundae).

• School Mathematics
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• v.18 no.2
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• pp.425-440
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• 2016

Concept images play an important role in the acquisition of mathematical concept. However, sometimes concept images are derivatives of student's misconceptions. In addition, students always learn concept images despite teachers' efforts to teach concept definitions. Therefore, teachers need to know about all the concept images of a particular concept. This study aimed to analyze the concept image that students have about the triangle when they have already learned about the triangle in school. It was found that some students have different concept images about the triangle between Semo. Moreover, many students have misconceptions about vertices, sides, and angles. In particular, students think Gak denotes a side, although it means angle. Based on these results, I suggest that the curriculum and textbook require improvement.

• Journal of Embryo Transfer
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• v.22 no.4
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• pp.199-208
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• 2007

Although many studies have focused on the biological and toxicological effects of phenol products, in particular, in reproductive tracts, the data about their effects in this estrogenic responsive tissue are much less clear. In addition, the in vitro and in vivo data concerning ED-adverse impacts in other endocrine organs, i.e. pituitary gland, are not understood well either. Thus, a further study is needed for providing a new insight into possible impacts of estrogenic EDs including phenol products in humans and wildlife. A combination of in vitro and in vivo system for examining EDs may bring better understanding into the regulatory mechanisms underlying EDs-induced events. In addition, this information may support for developing optimal screening methods of estrogenic EDs, in particular, phenol products.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.324-332
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• 2000

The purpose of the study was to assess customer satisfaction concerning service quality characteristics of university foodservice by using a developed DINESERV model. In particular, it was intended to develop a tool to assess the difference between customer judgements on importance and customers perceptions with actual service delivery by university foodservices. Quenstionnaires were distributed to 1,000 university students. A total at 820 university students responded with a usable response rate of 77.7%. A statistical data analysis was completed using SAS programs for descriptive analysis; a t-test, chi-square test and Dunan's multiple range test. The results of the study are as follows; 1) The mean number of students visiting university foodservices per week for males was larger than that of females. The students' first choice depended on distance when they selected foodservices. They answered their preference as the first factor when they order a particular menu items in foodservices. The first complaint factor concerning university foodservices was the price of the food. 2) Customers was not satisfied with the quality of the service of university foodservices. The important mean score of the service quality was 3.63 out of 5, but the perception mean score of the service quality was 2.87. Therefore, there was a gap(0.76) between the importance score and perception score. 3) Customers' satisfaction with the service quality by dimensions wee int he follow order: assurance>reliability>responsiveness>tangibles>empathy. Customers were more satisfied with the service quality of contracted management than that of self-operated facilities.

• Economic and Environmental Geology
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• v.28 no.5
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• pp.527-533
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• 1995

A disadvantage of Fourier analysis is that frequency information can only be extracted for the complete duration of a signal f(t). Since the Fourier transform integral extends over all time, from $-{\infty}$ to $+{\infty}$), the information it provides arises from an average over the whole length of the signal. If there is a local oscillation representing a particular feature, this will contribute to the calculated Fourier transform $F({\omega})$, but its location on the time axis will be lost There is no way of knowing whether the value of $F({\omega})$ at a particular ${\omega}$ derives from frequencies present throughout the life of f(t) or during just one or a few selected periods. This disadvantage is overcome in wavelet analysis which provides an alternative way of breaking a signal down into its constituent parts. The main advantage of the wavelet transform over the conventional Fourier transform is that it can not only provide the combined temporal and spectral features of the signal, but can also localize the target information in the time-frequency domain simultaneously. The wavelet transform distinguishes itself from Short Time Fourier Transform for time-frequency analysis in that it has a zoom-in and zoom-out capability.

• The Journal of the Korea Contents Association
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• v.8 no.2
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• pp.33-40
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• 2008

In various manners, string pattern matching algorithm has been proven for prominence in speed of searching particular queries and keywords. Whereas, the existing algorithms are limited in terms of various pattern. In this paper, regular expression has been utilized to improve efficiency of pattern matching through efficient execution towards various pattern of queries including particular keywords. Such as this research would enable to search various harmful string pattern more efficiently, rather than matching simple keywords, which also implies excellent speed of string pattern matching compared to that of those existing algorism. In this research, the proposed string search engine generated from the LEX are more efficient than BM & AC algorithm for a string patterns search speed in cases of 1000 with more than patterns, but we have got similar results for the keywords pattern matching.

• Korean Institute of Interior Design Journal
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• v.25 no.3
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• pp.60-69
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• 2016

This experimental study measures the emotional and physiological responses of customers as to cafe facade design. It is done through eye-tracking and EEG response experiments. Specifically, their visual concentration and EEG concentration are analyzed in line with their facade preferences. The findings are as follows. First, the correlation between their facade preferences and visual concentration on facades is as follows: Highly preferable facades have a lower visual concentration frequency than the less preferable facades. Second, an analysis of $12{\times}12$ lattice division of facades shows that all facades have a high visual concentration for signs. The exceptions are F(6), F(7), F(8), and F(10). There is no correlation between the facade preferences and visual concentration behaviors for particular facade elements. Third, an analysis of prefrontal lobe's facade concentration shows that there is no correlation between the preferences and EEG concentration. However, there are big differences in the prefrontal lobe activity of 12 subjects depending on the facade. In particular, nine of them (3, 9, 13, 14, 15, 28, 36, 38, 43) show an activated prefrontal lobe as to the highly preferable facades-F(1), F(2), F(3), and F(4). However, such activation is not detected on the less preferable facades-F(9), F(10), F(11), and F(12).