• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.4
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• pp.413-420
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• 2003

In this paper, the correction method of antenna beam direction errors is introduced which caused by frequency scan effect in active Phased may antenna for satellite communications. The antenna makes the beam directional error from frequency scan effect when it has dual beam may structure with asymmetrical series connection, their frequencies are different and for from each other, their 3dB beamwidth is narrow, and scan range is wide. By proposed equations, estimated beam direction error angles can be calculated and active phase shifter control values also can be calculated to compensate them. In this paper, the active phased array antenna system was fabricated to measure beam direction errors both before and after correction, which has dual beam from 32${\times}$4 main level array and 4${\times}$2 second level array, frequency deviation 500 MHz max.(6.7 %) at 7.25 GHz∼7.75 GHz ranges, 0$^{\circ}$∼${\pm}$35$^{\circ}$nm ranges, and 35.6 dBi gain with 2.2$^{\circ}$3 dB beam width. Its beam direction error by frequency san effect which was 2.5$^{\circ}$max., was reduced to 0.2$^{\circ}$max. after correction. This was 7 dB improvement of signal loss. The active phased array antenna can accurately track the target satellite for communications by this proposed correction method.

• Journal of Korean Public Health Nursing
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• v.2 no.2
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• pp.5-20
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• 1988

This study is a series of reviews in connection with the application of the Questionnaire THI, in order to intend to provide such datum to be of a help as the screening-test by means of getting through comparative analysis, and finding out existence of any disease appeared as a result of the general medical examinations, and the psychosomatic symptoms, through the questionnaire THI. This study had been researched through the 507 insureds of the life insurance residing in Seoul and in the suburbs of Seoul, during the period 5 Jan. 1987 to 27 Feb. through the questionnaires. Exception of the 88 insincere respondents out of the total objectives, the 419 questionnaires were nanlized through percentage, Mean, T-test, ANOVA test, and Discriminant Analysis. 1. The Subjective Health Problem of the Objectives: The average of the health problem appliation quorum appeared to be 1. 81, the articles of both nervousness and aggressiveness appeared to be each 2.25 and 2.04. It tells that the state of appliation is heavy. It was very significant statistically the relation between the elements of sex, ages, educational backgrounds and occupations. 2. The result of the General Examination of the Objectives: The number of the persons with abnormal findings was 300 persons among the total of 419 persons as a result of the general medical examinations, and it was applicable to $73.5\%$. By each age and marital state were statistically significant. 3. Comparison of the result of the General Examination and Subjective Health of those Objectives: As a result of discriminant analysis of the independent variables through the result of the general examination, the greatest element for influence appeared to be the age, and then, regular examination, sex, and the somatic complaints of the THI in order. Accordingly, it is considered to be able to function as the screening test of the general examination, the THI. In case of a greater unit of group required a medical examination, It is considered to be of a help for the health management service for more effective and precise in quality and economic, only if a medical examination is carried out after selecting the somatic subjective problem and research in advance to the application of the THI prior to the examination.

• Journal of the Korean Solar Energy Society
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• v.30 no.6
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• pp.73-80
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• 2010

This study was conducted to estimate the relative performance of modules with changed characteristics due to long term exposure to the outdoor environment, with a specially made test device for simultaneous measurement of real time power output from the photovoltaic array, taking into account the inclined panel, direct irradiation, power being generated, temperature as well as the optimal analysis timing. In terminology description, M is an abbreviation of module and Group A, Group B are 10 modules series connection (1~10 of M), (11~20 of M) for each of them respectively. The overall mean voltage difference of M-18 with the lowest power output and M-14 with the highest output is-2.13V and it was identifiable that voltage difference was more concentrated to Group B. In addition, in case of M-2 and M-7, M-8, when compared with M-14, the overall mean voltage difference was -0.92V, -1.56 and -0.91V respectively showing the more concentration to Group A. When the temperature of module went up by $1^{\circ}C$, the mean voltage was reduced by 0.35V. For current, Group A was lower than Group B by-0.022A and the ratio of each group was 49.68% and 50.32% respectively, presumably the module with deteriorated properties were more concentrated to Group A relatively. From the comparison of relations with the comprehensive accumulation, M-2, M-7, M-8, M-16 and M-18 were those with deterioration of performance to the worst, thereby requiring precision examination. In comparative efficiency, M-14 was the most excellent one as 12.19% while M-18 as 10.53% was identified that its efficiency was comparatively rapidly reduced.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.1
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• pp.91-99
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• 2008

A multilayer tower-type photoreactor, in which $TiO_2$-coated glass-tubes were installed, was used to measure the vapor-phase BTEX removal efficiencies by ozone oxidation ($O_3$/UV), photocatalytic oxidation ($TiO_2$/UV) and the combination of ozone and photocatalytic oxidation ($O_3/TiO_2$/UV) process, respectively. The experiments were conducted under various relative humidities, temperatures, ozone concentrations, gas flow rates and BTEX concentrations. As a result, the BTEX removal efficiency and the oxidation rate by $O_3/TiO_2$/UV system were highest, compared to $O_3$/UV and $TiO_2$/UV system. The $O_3/TiO_2$/UV system accelerated the low oxidation rate of low-concentration organic compounds and removed organic compounds to a large extent in a fixed volume of reactor in a short time. Therefore, $O_3/TiO_2$/UV system as a superimposed oxidation technology was developed to efficiently and economically treat refractory VOCs. Also, this study demonstrated feasibility of a technology to scale up a photoreactor from lab-scale to pilot-scale, which uses (i) a separated light-source chamber and a light distribution system, (ii) catalyst fixing to glass-tube media, and (iii) unit connection in series and/or parallel. The experimental results from $O_3/TiO_2$/UV system showed that (i) the highest BTEX removal efficiencies were obtained under relative humidity ranging from 50 to 55% and temperature ranging from 40 to $50^{\circ}C$, and (ii) the removal efficiencies linearly increased with ozone dosage and decreased with gas flow rate. When applying Langmuir-Hinshelwood model to $TiO_2$/UV and $O_3/TiO_2$/UV system, reaction rate constant for $O_3/TiO_2$/UV system was larger than that for $TiO_2$/UV system, however, it was found that adsorption constant for $O_3/TiO_2$/UV system was smaller than that for $TiO_2$/UV system due to competitive adsorption between organics and ozone.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.639-647
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• 2011

In this paper, we introduce a design methodology of data-centroid Radial Basis Function neural networks with extended polynomial function. The two underlying design mechanisms of such networks involve K-means clustering method and Particle Swarm Optimization(PSO). The proposed algorithm is based on K-means clustering method for efficient processing of data and the optimization of model was carried out using PSO. In this paper, as the connection weight of RBF neural networks, we are able to use four types of polynomials such as simplified, linear, quadratic, and modified quadratic. Using K-means clustering, the center values of Gaussian function as activation function are selected. And the PSO-based RBF neural networks results in a structurally optimized structure and comes with a higher level of flexibility than the one encountered in the conventional RBF neural networks. The PSO-based design procedure being applied at each node of RBF neural networks leads to the selection of preferred parameters with specific local characteristics (such as the number of input variables, a specific set of input variables, and the distribution constant value in activation function) available within the RBF neural networks. To evaluate the performance of the proposed data-centroid RBF neural network with extended polynomial function, the model is experimented with using the nonlinear process data(2-Dimensional synthetic data and Mackey-Glass time series process data) and the Machine Learning dataset(NOx emission process data in gas turbine plant, Automobile Miles per Gallon(MPG) data, and Boston housing data). For the characteristic analysis of the given entire dataset with non-linearity as well as the efficient construction and evaluation of the dynamic network model, the partition of the given entire dataset distinguishes between two cases of Division I(training dataset and testing dataset) and Division II(training dataset, validation dataset, and testing dataset). A comparative analysis shows that the proposed RBF neural networks produces model with higher accuracy as well as more superb predictive capability than other intelligent models presented previously.

• School Mathematics
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• v.16 no.4
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• pp.827-845
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• 2014

This study aims to investigate how the university educational programs about quadratic curves are operated in relation to the high school curriculum and what their effects may be, and the degree of understanding for the prospective and current teachers of the mathematical content knowledge about quadratic curves. To solve this research questions, we randomly selected three universities and one high school. Then we investigated the curricula of each department of mathematics education, compared them with the high school curricula, and conducted surveys of the professors' and students' conception on how much mathematical content knowledge they need to know about quadratic curves. The study resulted in the following conclusions. First, the curriculum on the subject of quadratic curves in the college of education is closely connected to the high school programs. This study's results showed that the college of education's curriculum includes a series of lectures regarding quadratic curves, and that within them, the mathematical content about quadratic curves associated with high school mathematics was thoroughly covered. Also, a large number of students who attended the lecture reported a significant increase in their understanding in regards to the quadratic curves. Second, it is strongly recommended to strengthen the connection between the college of education's curriculum and the actual high school education field. The prospective teachers think that there is a substantial need to learn about the quadratic curves because it is closely connected with the high school curriculum. But they find it challenging to put what they were taught into practical use in the high school education field, and feel that an improvement in this area is much needed. Third, it is necessary to promote, encourage and support the voluntary efforts to expand the range of the content knowledge in quadratic curves to cover the academic content associated with the high school mathematics.

• Applied Biological Chemistry
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• v.7
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• pp.1-13
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• 1966

1) Three ${\beta}-1$, 4-mannanases were isolated from germinated guar bean through extraction, ammonium sulfate fractionation, column chromatography on cellulose derivatives and gel filltration on Sephadex G-100. They were designated as ${\beta}-1$, 4-mannanase A,B and C, respectively, in the order of isolation. 2) These enzymes were different in several aspects such as pH optimum, effect of metal ions, adsorbability on cellulose derivatives, molecular weight, Michaelis constant toward reduced ivory nut mannan A, mode of action and extent of hydrolysis of the mannan. 3) ${\beta}-1$, 4-Mannanases A and C were proposed to be two different endo-enzymes of random-splitting type producing a series of oligosaccharides from ${\beta}-1$, 4-mannans. ${\beta}-1$, 4-Mannanase B was suggested to be possibly an exe-type enzyme catalyzing a stepwise splitting from the non-reducing end of ${\beta}-1$, 4-mannans to produce mannose. 4) Guaran was subjected to hydrolysis by the purified enzymes and the consequence was discussed in connection with structural requirements of the enzymes toward substituted ${\beta}-1$, 4-mannans and their role in germinating guar seeds.

• Cross-Cultural Studies
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• v.42
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• pp.131-163
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• 2016

The issue of migrants has always been a social problem in France. Particularly, migration issues from the Maghreb region to multicultural France are recognized as topics of confrontation and conflict. One of the many reasons would be that the Maghreb migrant issue is interpreted with a hostile or conflicting 'Arab-Islam' meaning in the West. Therefore, the naming of natives from this region as 'Arab-Maghrebis' has become a common phenomenon. However, deeper understanding of the Maghreb region will explain that such naming could produce a number of problems. This is because the native Maghrebis, not only in the Maghreb region but also in France, are Berbers. Among the various Berbers, the Kabyles are in many ways different from the Arabs in their language, culture, and way of thinking. Apart from the difference in their lifestyle, there is a deep anti-Arab sentiment within them that represents their resistance against the hundreds-of-years Arab domination. This feature has also been used as France's tool of colonial division policy during the colonization period. The purpose of this study is to discuss the settlement process of the Kabyles in France by paying attention to their features. The Kabyles were the first to migrate to France among the natives of the Maghreb region. This study focuses on the process of their migration and search for identity, as well as how they continued to form community and the Berber's cultural movement. Through these series of processes, it is possible to point out the fictitious claim in France and in Korea that Maghrebis are Arab-Muslims. Lastly, the current use of Berber language in France and Algeria is not a coincidental phenomenon, rather it has a connection with the prolonged cultural movement and the settlement process of the migrants in France.

• Journal of Conservation Science
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• v.36 no.6
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• pp.578-590
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• 2020

During the 1960-1970s, a group of ceramic conservation scientists and ceramic historians in South Korea came together and established their own disciplines. While the two disciplines share the same ceramics as the subjects of their research, there has been little interaction between the two as their research outputs are articulated in remarkably different languages. This paper aims to address the following questions by using a case study that focuses on the research on white porcelains centered on the project of Gyeonggi Museum and a series of studies conducted by one of the museum's project research teams. First, what are the characteristics of and differences between the explanation styles of the two disciplines that share the same research subjects of ceramics? Second, why has the communication between the two disciplines become difficult? Third, if there can be a trading zone wherein the two disciplines would be able to communicate again, what would be its epistemic conditions? The focus of this paper is the relationship between scientific data and ordinary language, which the two disciplines have shared from their inception. By analyzing the relationship, I first argue that, as the analytical techniques of conservation science have become more developed, conservation science's data have gradually lost its relevance in ceramic history, in spite of a shared common language between them; Second, I argue that by recovering the import of shared language again, the scientific data can be placed in a different practical context, providing novel interpretations that are relevant and often consequential to ceramic history.

• (The)Study of the Eastern Classic
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• no.69
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• pp.233-258
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• 2017

The purpose of this paper is as follows: The book, , which Yi Yang-o read, is to find out what kind of series it was. Second, I will examine the way of expressing the preface that I wrote after and try to analyze the part where Lee Yang-ho took interest in . Lee Yang-o was more concerned about the soft-handedness and the eavesdropping than the person named Sasu and Kyo. It can be understood in connection with the social problems of the 18th century and the situation of Lee Yang-ho. In other words, there was a great interest in the reality, the torture of the reins of war wanted the world to live, and the was a work that reminds us of the torture of reeling. I was able to find out that Lee Yang-o was involved with the problem of reality in which he lived, criticized concrete reality contradicted reality, and struck down his intention to do so.