• Journal of Hydrogen and New Energy
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• v.28 no.2
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• pp.212-219
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• 2017

As an environmental pollution and global warming due to an excessive carbon emission are intensified, the importance of renewable energy is in rise today. TCP (Tidal Current Power), one of the renewable energy sources, generates electricity by converting kinetic energy of current into rotational energy of turbine. Also the TCP has a great advantages of predictability and reliability. Because the generating power is proportional to cubic of stream velocity, amplifying current speed by applying duct is highly effective to increase the generating power. SPM (Single Point Mooring) can be applied for the weather vane with various current direction and also augments generating power of the system. In addition, simple installation and retrieval could be a merit of SPM system. By combining duct and SPM, TCP system for relatively low-speed-current and shallow water region can be feasible and economical. In this study, single point moored duct-type TCP system was designed and the motion of submerged structure was investigated in both numerical and experimental method. DNV wadam V4.8-1 and OrcaFlex 10.0a were used for the frequency and time domain motion analysis of system respectively. Duct model scaled by 0.05 of Froude conformity ratio and CWC (Circulate Water Channel) are used for experiment.

• Archives of design research
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• v.17 no.2
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• pp.479-486
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• 2004

We need to seek after new direction and order of design that puts more value on the spirits and culture of human beings in the 21st century, creating a new, all-inclusive value in which individual human being, the society and the environment can co-exist in a peaceful relationship by overcoming the materialistic, analytical, competitive, and differentiated values of traditional industrial society. The aim of this study, then, is to present a new method of design that can meet the demands of the 21st century in a civic age of information, knowledge and culture, by focusing on Monistic ideals derived from a deeply rooted Oriental philosophy. The concept of Monism is embodied by a mind set that treasures the benefit to others over rewards to the self, puts more importance on the spiritual life hidden behind physical phenomena, thinks more of what lacks than what exceeds, elevates the mind over the body, and seeks after beauty via a total harmony of balance and development that can be feasible only by combining all these elements. Ultimately, the new design principle based on the Monism consists of three basic elements: (1) identification of the subject and the object between things under the perception that all things are one (Unification); (2) the ability that helps things exist with appropriate beauty maintaining balance and stability (Harmony); and (3) the attitude of sharing to maintain sustainable vitality by filling up what lacks or is missing in a whole(Change).

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.101-106
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• 2008

This paper describes a comparative study of genetic algorithm and mathematical programming technique applied in the design optimization of geodesic dome. In particular, the genetic algorithm adopted in this study uses the so-called re-birthing technique together with the standard GA operations such as fitness, selection, crossover and mutation to accelerate the searching process. The finite difference method is used to calculate the design sensitivity required in mathematical programming techniques and three different techniques such as sequential linear programming (SLP), sequential quadratic programming(SQP) and modified feasible direction method(MFDM) are consistently used in the design optimization of geodesic dome. The optimum member sizes of geodesic dome against several external loads is evaluated by the codes $ISADO-GA{\alpha}$ and ISADO-OPT. From a numerical example, we found that both optimization techniques such as GA and mathematical programming technique are very effective to calculate the optimum member sizes of three dimensional discrete structures and it can provide a very useful information on the existing structural system and it also has a great potential to produce new structural system for large spatial structures.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.325-330
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• 2011

In order to revive the ecological function of degraded rivers, a total restoration plan for riverbeds and riparians needs to be developed. Previous evaluations for rivers were mainly focused on the river's physical structures. Therefore, this research has developed indicators to evaluate a riparian restoration considering biodiversity. Through literature and previous cases review, 4 fields and 13 indicators are selected for the evaluation. Four fields are biodiversity, habitat diversity, connectivity and habitat functionality. In the biodiversity field, 4 indicators of the exuberant extent of herbaceous vegetation and their diversity, the exuberant extent of shrub and woody plants and their diversity, the number of plant communities and naturalized plants are included. Habitat diversity are comprised of 4 indicators of the longitudinal continuity of vegetation, the mixture of plant communities, the extent of plant type color fruit abundance and the distribution of vegetation. Connectivity includes 3 indicators of target distribution, the shore slope of low water channels and the extent of artificial embankment materials. Habitat functionality has 2 indicators of the status of food supply plants and the habitat functionality. The value weighting for the fields and indicators has been calculated based on the AHP(Analytic Hierarchy Process) method. 50 experts were surveyed with quantifiable questionnaire, among them 43 experts have more than 10 yesrs experiences in the nature restoration field. The selected and weighted indicators have been tested to the 12 sections in Gap stream located in Daejeon. In conclusion, the indicators are feasible and the selected indicators could be used to establish the direction and objectives of riparian restoration.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.2
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• pp.7-15
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• 2010

An early stage of general hospital in Korea was the quantitative growth period. Remodeling has been required to meet the increasing medical demands. To accept the change of paradigm and management operation method, remodeling occurred from the 20th century. Remodeling plans are difficult to define the direction of the detailed plan due to various factors in the beginning of the construction, Therefore, it is necessary to analyze the possibility and limitation of a feasible remodeling plan of general hospitals through the comparison of existing hospital before remodeling and after the remodeling takes effect. A comparison of the researched hospital's blue prints before and after the remodeling and recently built hospital's blue print, analyzed characteristic of the space variation by the remodeling. The purpose of research is to confirm a possibility and limitation of remodeling of general hospitals comparing with merits and faults of extension, reconstruction, and construction. In conclusion, the area of remodeling hospitals increase mostly medical department(ward, outpatient department, inpatient department) and subsidiary facilities, but the area of ward and inpatient department are less than the new hospitals. Especially, public area is greatly increased by the diversification of corridor function. Also, remodeling hospitals represent a limitation to plan departments in need of equipment-intensive space. To address this problem, expansion space is used mainly with inpatient department and existing space is placed mainly with low-impact department by equipment ; outpatient department, administration department.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.9
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• pp.1408-1414
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• 2004

The use of flip-chip technology has many advantages over other approaches for high-density electronic packaging. ACF (anisotropic conductive film) is one of the major flip-chip technologies, which has short chip-to-chip interconnection length, high productivity, and miniaturization of package. In this study, thermal fatigue lift of ACF bonding flip-chip package has been predicted. Elastic and thermal properties of ACF were measured by using DMA and TMA. Temperature dependent nonlinear hi-thermal analysis was conducted and the result was compared with Moire interferometer experiment. Calculated displacement field was well matched with experimental result. Thermal fatigue analysis was also conducted. The maximum shear strain occurs at the outmost located bump. Shear stress-strain curve was obtained to calculate fatigue life. Fatigue model for electronic adhesives was used to predict thermal fatigue life of ACF bonding flip-chip packaging. DOE (Design of Experiment) technique was used to find important design factors. The results show that PCB CTE (Coefficient of Thermal Expansion) and elastic modulus of ACF material are important material parameters. And as important design parameters, chip width, bump pitch and bump width were chose. 2$^{nd}$ DOE was conducted to obtain RSM equation far the choose 3 design parameter. The coefficient of determination ($R^2$) for the calculated RSM equation is 0.99934. Optimum design is conducted using the RSM equation. MMFD (Modified Method for feasible Direction) algorithm is used to optimum design. The optimum value for chip width, bump pitch and bump width were 7.87mm, 430$\mu$m, and 78$\mu$m, respectively. Approximately, 1400 cycles have been expected under optimum conditions. Reliability analysis was conducted to find out guideline for control range of design parameter. Sigma value was calculated with changing standard deviation of design variable. To acquire 6 sigma level thermal fatigue reliability, the Std. Deviation of design parameter should be controlled within 3% of average value.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.7
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• pp.612-618
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• 2007

The dynamic behaviors of a KT-1 family aircraft nose landing gear have been analyzed and the optimal design of an aircraft shock absorber has been conducted to improve efficiency of shock energy absorption. The nose landing gear is modeled as a 2 DOF system using ADAMS and various operational and environmental landing conditions were considered. The results of dynamic simulation for various landing conditions agree well with experiments. Also the effect of parameters of a shock strut on the dynamic behaviors and on shock energy absorption of the nose landing gear has been evaluated for optimal design to define design variables. It has been found that the parameters of a shock strut such as oil-density and orifice area have more effects on dynamic behaviors than those of operation conditions. Optimal design is performed to maximize the efficiency of shock energy absorption using Feasible Direction Method. As a result the design values of the shock strut for maximum efficiency of shock energy absorption are derived and it turns out that efficiency and dynamic behaviors of the nose landing gear were improved by the optimal design.

• Korea Journal of Hospital Management
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• v.13 no.4
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• pp.119-145
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• 2008

The objectives of this study were to inspect how the law effected on hospital employment system and which policy and strategy are needed to cope with the present situation as the law regarding irregular workers law has enacted for a year. To grasp the changes of employment style in hospital, 56 hospitals among 311 general hospitals were questioned in this study. And employment policy and strategy were developed by referencing examples of developed nations and other industries. The survey showed that the wage and welfare level of irregular workers in hospitals was improved compared to that in the other industries. But there were still much discrimination between regular and irregular workers. The policy direction of government is, first of all, to follow the principle of equal treatment to equal value of labour. The first feasible policy is to enforce social security. The second one is an employment promotion policy which reduces or exempts hospitals employing irregular workers from tax and insurance fee. The third one is to extend employment contract period to 3 years. and finally there are policies to permit more dispatched jobs and to expand the social insurance coverage. The strategies to solve the problem of irregular workers are as follows; 1) performance wage system, 2) guaranteeing employment by unlimited contract, 3) creating new category of workers, 4) the wage system of management by object, 5) the method of job classification. This study has a meaning in the point that it was studied on hospital which is special industrial part and analyzed the changes after enacting irregular workers law and presented management strategy for countermeaure program. In this study, it was expected to contribute to decisions-making in hospital management, especially when using human resources.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.11
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• pp.1147-1152
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• 2004

The objective of this work is to develop a new design method to find optimal coils, especially the optimal coil configuration of an optical pickup actuator. In designing actuator coils, the developed Lorenz force in the coils along the desired direction should be made as large as possible while forces and torques in other directions should be made as small as possible. The design methodology we are developing is a systematic approach that can generate optimal coil configurations for given permanent magnet configurations. To consider the best coil configuration among all feasible coil configurations, we formulate the design problem as a topology optimization of a coil. The present formulation for coil design is noble in the sense that the existing topology optimization is mainly concerned with the design of yokes and permanent magnets and that the optimization of actuator coils is so far limited within shape or size optimization. Though the present design methodology applies to any problem, the specific design example considered is the design of fine-pattern tracking and focusing coils.

• Cartoon and Animation Studies
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• s.16
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• pp.179-198
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• 2009

This study analyzed the chronology of children's cartoon through character while the children's cartoon section is planned at the Memorial Exhibition of 100th year of Korean Cartoon which will be held at the Contemporary Art Gallery in celebration of the 100th year after birth of Korean Cartoon. The approaching method based on character is regarded as the most proper and feasible in the identification of character and meaning of children's cartoon because the character in cartoon contains the bigger role and meaning than the descriptive structure of narration. The Committee of 100th Year of Korean Cartoon, Aicheorum which is a study association for children's cartoon and Cartoon My Love $Cafe^{42)}$ in Naver jointly selected the 70 cartoon characters. A brief history is established based on these characters through chronological classification in seven sectors of around 10 year session such as before 1950s of quickening period and liberation, 1950s, 1960s, 1970s, 1000s, 1900s and after 2000. It examined the historical meaning, its reflection and characteristics focused on the cartoon character and the cartoonist which were well-known to everybody not only the display according to chronological order. The study intented the stereoscopic illumination on the children's cartoon and character which were favored beyond the generations. In addition, the similarity and human relation among cartoonist to cartoonist and character to character were analyzed and traced to identity the fact that children cartoon character is not individualistic being but it lies on the extension of tradition and trend of eternal cartoon history Finally, hopefully it will make a contribution to activate the pure creative children's cartoon in Korea through reminding the importance of character in cartoon, affirming the industrial value and reflecting the direction and perspective of pure creative children's cartoon.