• Korean Journal of Cleft Lip And Palate
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• v.10 no.1
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• pp.57-65
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• 2007

It is well known that the main factor which contributes to the relapse of orthognathic surgery for Cleft Lip and Palate (CLP) patients is post-operative scar on hard and soft palate of maxilla. Therefore, to compensate the amount of relapse, though it cannot be the perfect way to prevent orthodontic, orthopedic relapse, the Le-fort I osteotomy of maxilla and set-back osteotomy of mandible are generally carried-out simultaneously. We are to review the factors contribute to the relapse of CLP patients after orthognathic surgery through this clinical case : The relapse of Skeletal Class III tendency immediately after orthognathic surgery for grown up CLP patients.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.1A
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• pp.41-46
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• 2003

A MF/HF marine whip antenna with side whips, which are connected at an angle with the straight main whip, has reported In this paper, the effects of side whips on the antenna are simulated by using NEC-WIN and a novel MF/HF ship antenna with side whips is designed First of all, the gain, return loss, and radiation pattern of the antenna on infinite perfect conductor plane are simulated as function of the parameters of the side whip, such as the number, the location, the length of the side whip and the angle with the main whip. After that, the size of the antenna is decided and set up on an experimental ship in Korea Maritime University. The antenna on the ship are simulated and the simulated input impedances are good agreement with the measured results.

• Journal of Communications and Networks
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• v.18 no.2
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• pp.173-181
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• 2016

In this paper, we address a new robust optimization problem in a multiuser multiple-input single-output broadcasting system with simultaneous wireless information and power transmission, where a multi-antenna base station (BS) sends energy and information simultaneously to multiple users equipped with a single antenna. Assuming that perfect channel-state information (CSI) for all channels is not available at the BS, the uncertainty of the CSI is modeled by an Euclidean ball-shaped uncertainty set. To optimally design transmit beamforming weights and receive power splitting, an average total transmit power minimization problem is investigated subject to the individual harvested power constraint and the received signal-to-interference-plus-noise ratio constraint at each user. Due to the channel uncertainty, the original problem becomes a homogeneous quadratically constrained quadratic problem, which is NP-hard. The original design problem is reformulated to a relaxed semidefinite program, and then two different approaches based on convex programming are proposed, which can be solved efficiently by the interior point algorithm. Numerical results are provided to validate the robustness of the proposed algorithms.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.339-342
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• 2010

This thesis is the analysis of programing cases by which each broadcasting station generates visual studio. When the broadcasting stations make programs, they overcome the visual limitation of expression by using visual studio other than the real set. This trend is the progress toward more realistic and delicate image by almost perfect image expression, not just broadcasting production by mere synthesis operation. It suggests the development direction toward visual studio production by analyzing production cases using domestic visual studio.

• Journal of the Optical Society of Korea
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• v.17 no.6
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• pp.513-517
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• 2013

Recently, maskless lithography (ML) systems have become popular in digital manufacturing technologies. To achieve high-throughput manufacturing processes, digital micromirror devices (DMD) in ML systems must be driven to their operational limits, often in harsh conditions. We propose an instrument and algorithm to detect DMD malfunctions to ensure perfect mask image transfer to the photoresist in ML systems. DMD malfunctions are caused by either bad DMD pixels or data transfer errors. We detect bad DMD pixels with $20{\times}20$ pixel by white and black image tests. To analyze data transfer errors at high frame rates, we monitor changes in the frame rate of a target DMD pixel driven by the input data with a set frame rate of up to 28000 frames per second (fps). For our data transfer error detection method, we verified that there are no data transfer errors in the test by confirming the agreement between the input frame rate and the output frame rate within the measurement accuracy of 1 fps.

• Journal of the Korean Mathematical Society
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• v.60 no.6
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• pp.1233-1254
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• 2023

We introduce two subclasses of abelian McCoy rings, so-called π-CN-rings and π-duo rings, and systematically study their fundamental characteristic properties accomplished with relationships among certain classical sorts of rings such as 2-primal rings, bounded rings etc. It is shown that a ring R is π-CN whenever every nilpotent element of index 2 in R is central. These rings naturally generalize the long-known class of CN-rings, introduced by Drazin [9]. It is proved that π-CN-rings are abelian, McCoy and 2-primal. We also show that, π-duo rings are strongly McCoy and abelian and also they are strongly right AB. If R is π-duo, then R[x] has property (A). If R is π-duo and it is either right weakly continuous or every prime ideal of R is maximal, then R has property (A). A π-duo ring R is left perfect if and only if R contains no infinite set of orthogonal idempotents and every left R-module has a maximal submodule. Our achieved results substantially improve many existing results.

• Journal of Venture Innovation
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• v.1 no.1
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• pp.181-195
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• 2018

The purpose of this study is to investigate the effect of service quality of a theater on the customer experience value and performance satisfaction and to test causality between variables. For this purpose, Study model was created from the previous studies and performed a survey with the customer who visited Performance Theater. In this study, employee kindness, facility excellence, convenience, and facilities were set as independent variables, and performance satisfaction was selected as a dependent variable. The cultural value and economic value of customer experience were examined as Moderating variables between two variables. Based on the results of this study, It was found that employee's kindness, facility excellence, and convenience have a significant effect on performance satisfaction in performing arts facilities. convenience, there was perfect mediated effect of customer experience between service quality of a theater and performance satisfaction centered on cultural value and economic value. The employee's kindness variable was examined as a perfect mediation of cultural value, and economic value as a sectoral mediation. The excellence variables of the facilities appeared as partial mediations in cultural values and as complete mediations in economic values. In the case of the auxiliary facilities, the significance test failed. According to the results of the research, it was confirmed that convenience service for customers is the most important variable. This result suggests that the service quality of a theater should be basically maintained in terms of the kindness of the facility and staff, and that the customer is more satisfied with the performance than the audience convenience service provided from the Theater. The venue suggests that customer service and reception, purchase of tickets, refund method, and staff training should be thoroughly done so that audiences can make the Theater.

• Journal of the Korean Society of School Health
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• v.6 no.2
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• pp.24-55
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• 1993

School health aims to guide and manage growing students from elementary schools to high schools in order to grow healthily through the formation of healthy life habits, the self-control health management guide and the making of pleasant school health environments. Even though this school health plays an important role in guiding the students who are in the period of growing to have a perfect personality as a democratic people of our country in the school education, there are many lacks, such as they still don't know the word itself, "school health" or recognize its importance. Also it's a real condition to practice items concerned with the health under the condition of unestablished structure. 1. The results of analyzing school health real conditions. Based on treatises concerned with school health and various statistical materials which are announced by concerned people. We divided and analyzed school health into the items concerned with health education, the items with health management, and the items with school health environments, and investigated the level of the present school health and its necessity. As the items concerned with health education, we investigated the necessary range of school health education, the effect of health education on children's daily life, family's health and the interesting contents of school health. And as the items with health management, I investigated children's obesity, dental caries, eyesight, clinics, a health examination, drug abuse, spirit health, providing meals for school children, and school health manpower. And as the items conerned with school health environments, we investigated the recognition of the problem of natural environments, the management of purification district around the school, the problem of environments within the school and classroom lighting. As the results of analyzing these, I realized that the present level of school health is still in unsatisfactory situation and school health is needed necessary. 2. The establishment of school health. In order to set the school health, above all, the management system of School health should be set. I classified and systemized the contents of each item which had been promoted till now according to the function. They are classified as followings Based on classifying school health into (1) health education, (2) health management and (3) health environments, I divided school health education into the health education of health subjects, the health education of concerned subjects and the education of health life. And I divided health management into the health managements for a prevention and a cure. And I divided health environments into the environment around the school and within the school. Each system set like these is not fixed invariably and I should keep the relationship of mutual supplement between health education and health management, between health management and health environments, and between health environments management and health education. When we run these systemetic school health, students' health could be maintained and improved to more proper directions.

• Asia Marketing Journal
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• v.16 no.1
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• pp.35-69
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• 2014

The impact of competition on pricing has been studied in the context of counterfactual merger analyses where expected optimal prices in a hypothetical monopoly are compared with observed prices in an oligopolistic market. Such analyses would typically assume static decision making by consumers and firms and thus have been applied mostly to data obtained from consumer packed goods such as cereal and soft drinks. However such static modeling approach is not suitable when decision makers are forward looking. When it comes to the markets for durable products with indirect network effects, consumer purchase decisions and firm pricing decisions are inherently dynamic as they take into account future states when making purchase and pricing decisions. Researchers need to take into account the dynamic aspects of decision making both in the consumer side and in the supplier side for such markets. Firms in a two-sided market typically subsidize one side of the market to exploit the indirect network effect. Such pricing behaviors would be more prevalent in competitive markets where firms would try to win over the battle for standard. While such qualitative expectation on the relationship between pricing behaviors and competitive structures could be easily formed, little empirical studies have measured the extent to which the distinct pricing structure in two-sided markets depends on the competitive structure of the market. This paper develops an empirical model to measure the impact of competition on optimal pricing of durable products under indirect network effects. In order to measure the impact of exogenously determined competition among firms on pricing, we compare the equilibrium prices in the observed oligopoly market to those in a hypothetical monopoly market. In computing the equilibrium prices, we account for the forward looking behaviors of consumers and supplier. We first estimate a demand function that accounts for consumers' forward-looking behaviors and indirect network effects. And then, for the supply side, the pricing equation is obtained as an outcome of the Markov Perfect Nash Equilibrium in pricing. In doing so, we utilize numerical dynamic programming techniques. We apply our model to a data set obtained from the U.S. video game console market. The video game console market is considered a prototypical case of two-sided markets in which the platform typically subsidizes one side of market to expand the installed base anticipating larger revenues in the other side of market resulting from the expanded installed base. The data consist of monthly observations of price, hardware unit sales and the number of compatible software titles for Sony PlayStation and Nintendo 64 from September 1996 to August 2002. Sony PlayStation was released to the market a year before Nintendo 64 was launched. We compute the expected equilibrium price path for Nintendo 64 and Playstation for both oligopoly and for monopoly. Our analysis reveals that the price level differs significantly between two competition structures. The merged monopoly is expected to set prices higher by 14.8% for Sony PlayStation and 21.8% for Nintendo 64 on average than the independent firms in an oligopoly would do. And such removal of competition would result in a reduction in consumer value by 43.1%. Higher prices are expected for the hypothetical monopoly because the merged firm does not need to engage in the battle for industry standard. This result is attributed to the distinct property of a two-sided market that competing firms tend to set low prices particularly at the initial period to attract consumers at the introductory stage and to reinforce their own networks and eventually finally to dominate the market.

• The Research Journal of the Costume Culture
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• v.17 no.3
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• pp.407-423
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• 2009

The purpose of this study is to analyze Bakst's stage costume illustrations for Ballets Russes. The Russian Ballets has renown in the West since the early 20th century. Diaghilev first made his name as the organizer of art exhibitions in Russia and Western Europe. Diaghilev risked presenting only ballets in 1909, that time Bakst designed $Sch{\acute{e}}h{\acute{e}}razade$, L'Oiseau de Feu and Le Carnival. $Sch{\acute{e}}h{\acute{e}}razade$ was something new which overwhelmed the French people by then. It was seen to be the achievement of Wagner's idea where all the elements; the music, the design, the choreography, and the dancing fused into a perfect whole. The entire production was a hitherto unseen harmony of colors, sounds and movements. For the 1911 season in Paris, Diaghilev planned to present six new ballets and Bakst designed four ballets. Bakst's design of the set and the costume greatly shocked the audience. His "Originality" shines on the fact that he introduced a palette of colors in theater for the first time in history. He used a magic of colors to suggest the secret meaning of what was happening on the stage. The results can be divided into three distinct characteristics. First, oriental designs such as $Cl{\acute{e}}op{\hat{a}}tre$, $Sch{\acute{e}}h{\acute{e}}razade$, L'Oiseau de Feu, La $P{\acute{e}}ri$ and Le Dieu Blue with Russian, Indian and Persian traditional design in headdress and accessories ars found. Second, Le Carnival and La Spectre de la Rose used romantic styles with oriental details. Third, Greek chiton and Himation are used in Narcisse, $H{\acute{e}}l{\grave{e}}ne$ de Sparte, $L'Apr{\grave{e}}s-Midi\;d^{\grave{\;}}un$ Faune and Daphnis et $Chlo{\acute{e}}$ inspirde with various colors and geometic patterns. Bakst's orient of lush colored costumes, head dress, cushions, rugs and hangings became the immediate fashion imitated by Parisian couture houses and interior decorators.