• 전자공학회논문지C
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• 제35C권4호
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• pp.50-59
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• 1998

This paper describes a 3.3V 8bit CMOS digital to analog converter (DAC) with two state current cell metrix architecture which consists of a 4 MSB and a 4 LSB current matrix stage. The symmetric two stage current cell matrix architecture allow the designed DAC to reduce hot only a complexity of decoding logics, but also a number of wider swing cascode curent mirros. The designed DAC with an active chip area of 0.8 mm$_{2}$ is fabricated by a 0.8 .mu.m CMOS n-well standard digital process. The experimental data shows that the rise/fall time, the settling time, and INL/DNL are6ns, 15ns, and a less than .+-.0.8/.+-.0.75 LB, respectively. The designed DAC is fully operational for the power supply down to 2.0V, such that the DAC is suitable for a low voltage and a low power system application. The power dissipation of the DAC with a single power supply of 3.3V is measured to be 34.5mW.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.23-26
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• 2009

The trend that an apartment is regarded as not only a substantial property called 'residence' but also 'means of self-expression' to consumers is increasing in the present housing marketing, and thus, the apartment brand image is settling down as an important field of marketing management. Therefore, the present study aimed to verify difference of brand attitude according to consentaneity between an image of a housing brand and self-image of consumers to propose one kind of direction of strategies for formation of a differentiated brand image. As a result of a research, the trend that consumers show more positive attitude on a brand apartment having a brand image closer to an ideal self-image was analyzed to exist even if it is weak, so it was confirmed that the consentaneity between a brand image and a self-image of housing products can become a variable having some influence on brand attitude. The survey method understood a brand image, a self-image and brand attitude by using a Likert's 5-point scale on apartment brands of upper three companies according to a study result of a national brand competitiveness index(NBCI) and understood self-consentaneity by using a distance measurement model of self-consentaneity of Sirgy(1982). The questionnaire for the present research was carried out by surveying students of D university and the PASW program was used for statistical data analysis.

• 한국의류학회지
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• 제33권10호
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• pp.1530-1540
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• 2009

Life expectancy has increased and people are more concerned with keeping their 'youth'. Appearance is a competitive edge and people are caught up in a baby face fad that has expanded into a culture and beauty trend. This study examined the definitions and phrenological characteristics of a baby face and the causes of the baby face fad in a review of the baby face as a "sociocultural and beauty cultural code" based on literature, journals, previous papers, and Internet materials. Anatomically speaking, a "baby face" refers to a face that keeps the features of a child's face without aging signs. The baby face fad gained momentum due to the influences of the digital culture, the encouragement of the mass media, changes to the social structure, dietary improvements, new living styles, and an evolving aesthetic sense. The results reveal the sociocultural backgrounds behind the "baby face fad" settling down as a part of culture in addition to the phrenological characteristics of a baby face. It is also estimated that the baby face fad could affect the beauty culture and trends as a social phenomena.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.179-181
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• 2003

Conventional P/PI speed controller of today's servo drives should be manually tuned the controller switching set-point by trial-and-errors, which may translate the drive system down-time and loss of productivity. The adjustable drive performance is heavily dependent on the qualify of the expert knowledge and becomes inadequate in applications where the operating conditions change in a wide range, i.e., tracking command, cceleration/deceleration time, and load disturbances. In this paper, the demands on simple controls/setup are discussed for industry servo drives. Analyzing the frequency content of motor torque command, P/PI control mode switching is automatically peformed with some prior knowledge of the mechanical dynamics. The dynamic performance of the proposed scheme assures a desired tracking response curve with minimal oscillation and settling time over the whole operating conditions. For comprehensive comparison of traditional P/PI control scheme, extensive test is carried out on actual servo system.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.28-32
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• 2000

There are many different chemical pollutants that originate from atmospheric deposition and transportational activities along roads. This paper review the characteristics of heavy metal pollution, relationships between land use and pollutant load in urban area. Four land use areas in Seoul were selected for sampling and study with different characteristics during the period from April 1998 and February 2000. A series of studies have been carried out concerning the physicochemical characteristics of the sediments settling down in a gully pot to evaluate the contamination for heavy metals. The sediment samples from gully pots were characterized by the chemical extraction experiments. Sediments are characterized by very high concentrations of heavy metals, probably because of a long-term accumulation of vehicle- and industrial-related pollutants. The characteristics of heavy metal pollution show that each land use has different sources of contaminations. Mean Zn concentration in Yeouido and Junggu areas is 2-3 times higher than those in Dobonggu area. This suggests that Zn may be derived from the source of automobile traffic. The mean concentrations of Cu and Cr are very significantly high in Junggu and Gurogu areas and indicate that the industrial activities may contribute to the accumulation of Cu and Cr in sediments. The low Pb levels throughout the whole study areas in Seoul can be accounted for the use of unleaded gasoline since 1987.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.694-699
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• 2005

This paper deals with a control technique of eliminating the transient vibration of a geared mechanical system. This technique is based on a model-based control with a rotational speed sensor in order to establish the damping effect at the driven machine part. A rotational speed sensor is installed in a driven gear, namely a bull gear. A control model is composed of a reduced-order mechanical part expressed as a transfer function between the rotational speed of the motor and that of the bull gear. This control model estimates a load speed after the rotational speed of the bull gear is acted on the transfer function. The difference between the estimated load speed and the motor speed is calculated dynamically and it is added to the velocity command to suppress the transient vibration generated at the load. This control technique is applied to a dies driving spindle of a form rolling machine. In this paper, the performance of this control method is examined by simulations. The settling time of the residual vibration generated at the loading inertia can be shortened down to about 1/2 of the uncompensated vibration level.

• 대한간호학회지
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• 제42권5호
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• pp.609-621
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• 2012

Purpose: The purpose of this study was to explore the experiences of Korean mothers in parenting children with Hunter's syndrome, an X linked recessive genetically inherited disease usually affecting boys. Methods: Data were collected from 14 mothers having children with Hunter's syndrome, through two focus group interviews and individual in-depth interviews. Qualitative data from the field notes and transcribed notes were analyzed using the grounded theory methodology developed by Strauss & Corbin (1998). Results: The core category about the process of rearing children with Hunter's syndrome was identified as "navigating in the maze". The process of rearing children with Hunter's syndrome passed through three phases; 'entering an unknown region', 'struggling to escape from the unknown region', 'settling down in the unknown region'. Conclusion: In this study "navigating in the maze", as the core category deeply showed joys and sorrows of mothers in the process of rearing their children with Hunter's syndrome. In this rearing process they gradually adjusted themselves to their given condition. Also they gained initiatively coping strategies to care for, and protect their children. Therefore health care providers can establish supportive programs in the clinical field to empower these mothers by reflecting their proactive coping strategies.

• 한국중재학회지:중재연구
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• 제19권1호
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• pp.67-98
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• 2009

Recently there are many cases on the intellectual property dispute. Among them some cases are solved through mediation and arbitration. Mediation and arbitration hold some advantage over court proceeding for intellectual property dispute. However the traditional litigation system has material limitation to settle down international intellectual property dispute. Without arbitration, litigation in court would be the only choice in case of no consensual settlement between the disputing parties. However, once being aware of the usefulness of the arbitration, people in international business widely realize that arbitration is generally preferred to litigation. Mediation is a method of settling dispute outside of court setting and many mediation committee are established since 1986 in Korea. Arbitrability has been a crucial issue in the intellectual property dispute. In most developed countries including the U.S.A. and Switzerland, arbitrability in the intellectual property dispute has been changed in recent years by law. Now in resolving the dispute with international intellectual property is needed for legal research, experience, working practices and knowledge of the intellectual property industry and so on.

• 한국정밀공학회지
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• 제19권10호
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• pp.120-129
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• 2002

An integrated structure and controller design approach for rotating cantilever beam is presented. An optimization method is developed for improving positioning performance considering the elastic deformations during high speed rotation and adopting the beam shape and the control gains as design variables. For this end, a dynamic model is setup by the finite element method according to the shape of the beam. The mass and stiffness of the beam are distributed in such a way that the closed-loop poles of the control system should be located leftmost in the complex s-plane. For optimization method, the simulated annealing method is employed which has higher probability to find the global minimum than the gradient-based down-hill methods. Sequential design and simultaneous design methods are proposed to obtain the optimal shape and controller. Simulations are performed with new designs by the two methods to verify the effectiveness of the approach and the results show that the settling time is improved for point-to-point position controls.

• 한국수산과학회지
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• 제21권4호
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• pp.195-205
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• 1988

Distribution of organic materials In the surface sediments was investigated in September 1983 in Chinhae Bay System. Bottom waters containing less than 1ml/l of dissolved oxygen were found in Masan Bay, and in part of Kohyonsong Bay and Wonmunpo Bay. Organic carbon content in the surface sediments of Masan Bay was about 25mg/g and it decreased with increasing distance from the inner Masan Bay. Mean organic carbon contents in Wonmunpo Bay and Kohyonsong Bay were 25.48 and 31.39mg/g, respectively, which are higher values than those in Masan Bay where large amount of domestic and industrial wastewaters art discharged into the surface water and extensive phytoplankton occurs almost year round. Mean organic nitrogen and pheophyton contents were also the highest in Kohyonsong Bay amont eight subareas. In Masan Bay, settling of organic materials on the surface sediments seemed to be not significant because of active tidal mixing and relatively small size of particulate materials. In Kohyonsong Bay and Wonmunpo Bay large fecal pellets produced in shellfish farms could be easily settled down on the sediment because of weak current regime. DO content in the bottom waters were low in the organic material rich areas, and that suggests biodegradation of organic materials in the surface sediments could be an important oxygen consuming process during the study period of September 1983.