• Nuclear Engineering and Technology
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• v.20 no.2
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• pp.120-131
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• 1988

A souce term model describes mathematically the source of radionuclides as they begin slow migration and decay in deep groundwater. Various source term models based on mass-transfer analysis and measurement-based source term models are reviewed. Ganerally, two processes are involved in leaching or dissolution: (1) chemical reactions and (2) mass transfer by diffusion. The chemical reaction controls the dissolution rates only during the early stage of exposure to groundwater. The exterior-field mass transfer may control the long term dissolution rates from the waste solid in a geologic repository. Mass-transfer analyses re3y on detailed and careful application of the governing equations that describe the mechanistic processes of transport of material between and within phases. If used correctly, source term models based on mass-transfer theory are valuable and necessary tools for developing reliable predictions.

• Nuclear Engineering and Technology
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• v.14 no.3
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• pp.138-147
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• 1982

A theoretical basis for analysis of plutonium-hearing fuel in a thermal nuclear power reactor has been established. The analysis of UO$_2$-PuO$_2$ fueled, light water moderated uniform lattice experiments has been performed. A unit cell program, KARATE, which is based on the theoretical models of GAM and THERMOS with some modifications, has been developed to generate a few-group cross-sections. These cross-sections are subsequently used in the diffusion theory code, KIDD, to compare the calculated values of the effective multiplication factor with the measured. The average value of the effective multiplication factor for 41 selected critical experiments is estimated to be 0.9997 with standard deviation of 0.43%. This illustrates the fact that KARATE/KIDD system can be effectively used for the analysis of uniform lattices of UO$_2$-PuO$_2$fuels.

• Journal of Korea Game Society
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• v.7 no.2
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• pp.21-32
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• 2007

It is significant to simulate scattering of light within media for realistic image synthesis; however, this requires costly computation. This paper introduces a practical image-space approximation technique for interactive subsurface scattering. We use a general two-pass approach, which creates transmitted irradiance samples onto shadow maps and computes illumination using the shadow maps. We estimate single scattering efficiently using a method similar to common shadow mapping with adaptive deterministic sampling. A hierarchical technique is applied to evaluate multiple scattering, based on a diffusion theory. We further accelerate rendering speed by tabulating complex functions and utilizing level of detail. We demonstrate that our technique produces high-quality images of animated scenes with blurred shadow at hundreds frames per second on graphics hardware. It can be integrated into existing interactive systems easily.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.1030-1033
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• 2007

Following conclusions about Taeyang meridian and Taeyang type were obtained through studies with reference to the books of ${\ll}$Donguibogam${\gg}$, ${\ll}$Hwangjaenaegyung${\gg}$, and ${\ll}$Special Lectures of Master Jisan on Medical cases${\gg}$ . Park noticed that there was difference in the development of 12 meridians among the individuals and tried to apply it in the diagnosis and the treatment of the disease, thereby creating the theory of the six meridian types. The literal basis is assumed to a phrase in ${\ll}$YoungChu GyungMaek${\gg}$ , ‘人經不同 絡脈異所別也’. Taeyang meridian runs through the back of the human body. The concept of TaeYang includes surface, starting point, diffusion of Yang Gi, and emission. Small intestine meridian of hand Taeyang manages the liquid and Bladder meridian of foot Taeyang manages the muscle. There is much flow of blood and less of Gi in Taeyang meridian which makes the connection to hair, flesh, liquid, muscle and vessel. Taeyang conceals and condenses objects because it belongs to Hansu according to division of Six atmospheric influences and to the winter. The articulation is stiff and urination and elimination are abnormal when disease occurs in this meridian. The pathology of Taeyang meridian would be the invasion of outer filthy Gi affecting the Bladder meridian of foot Taeyang which then again makes Kidney meridian of foot Soeum sick. The two meridians compose the outer part and the inner part of th body. The bladder itself becomes sick sometimes. The condition of less Gi in Taeyang meridian can easily result in the shortage of Gi, and much blood makes the person to have a lofty ideal or to have capricious behavior.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.253-261
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• 1987

Thermoacoustic oscillation of an air column induced by heated wires is investigated analytically and experimentally. Acoustic power generation from a single heater wire is estimated based on the result of heat transfer analysis and expressed in terms of the efficiency factor indicating the conversion efficiency from heat to acoustic energy. It is shown that the efficiency factor becomes maximum when the wire radius is the order of the coustic boundary layer thickness and the flow velocity is close to the thermal diffusion velocity. Onset condition of the column oscillation is obtained by equating the acoustic power generation at the heater to the power loss due to thermoviscous dissipation at the tube wall and the convection and radiationloss at the open ends of the tube. In estimating the acoustic power generation, the heater is treated as a stretched single wire by correcting the flow velocity to take into account the interactions between adjacent heater wires. Experiment is performed by using a spiral heater of 1mm diameter in an air column of 37mm diameter. The heat input to drive the oscillation is measured and compared with the theoretical prediction. A good agreement is found between the theory and experiment, which is regarded as a substantial verification of the present analysis.

• Journal of the Korean Society for Library and Information Science
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• v.16
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• pp.71-110
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• 1989

The purpose of this study is to investigate the influential factors creating the modern library thought in the latter part of Yi Dynasty. After Korea was forced to make a treaty opening up the country in 1876, Western civilization was introduced and reforms were carried out eventually. Various influential factors could be taken into consideration as follows. (1) The envoys to Japan after 1876 (2) Tourists party to Japan organized by Gentlemen in 1982 (3) The persons who studied abroad (4) Establishment of modern schools and development of publications: on the new learning. (5) News media and others Above all, the persons who studied abroad, such as Yu Gil Jun, Yun Chi Ho, etc., in early stage has contributed most to the extension of public recognition for modern library in Korea. Therefore it can be said that the formation of modern library thought in Korea was based on the theory of the Western library as was the Japan in the period of Meiji Restoration. Patriotic intelectualls in these days believed that reform of the educational system and the diffusion of knowledge was very much meeded in order to preserve an independent Korea and to build up national strength, and then nation-wide campaign for enlightenment was earried on. For that reason the movement of the national library establishment in 1906 also should be regarded from the same point of view, that is, as a part of the enlightenment campaign. Therefore it should not go unheeded that strong patriotism was always streamed under the ground of the library campaign as well as the new learning and new education campaign. Unfortunately every plan of Korean library movement had broken down and missed the chance for having experience of self-development because of the Japanese invasion.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.185-190
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• 1996

RFSP is a computer program to do fuel management calculations for CANDU reactors. Its main function is to calculate neutron flux and power distributions using two-energy-group, three dimensional neutron diffusion theory. However, up to now the treatment has not been true two-group but actually "one-and-half groups". In other words, the previous (1.5-group) version of RFSP lumps the fast fission term into the thermal fission term. This is based on the POWDERPUFS-V Westcott convention. Also, there is no up-scattering term or bundle power over cell flux (H1 factor) for the fast group. While POWDERPUFS-V provides only 1.5 group properties, true two-group cross sections for the design and analysis of CAUDU reactors can be obtained from WIMS-AECL. To treat the full two-group properties, the previous RFSP version was modified by adding the fast fission, up-scatter terms, and H1 factor. This two-group version of RFSP is a convenient tool to accept lattice properties from any advanced lattice code (e.g. WIMS-AECL DRAGON, HELIOS...) and to apply to advanced fuel cycles. In this study, the modification to implement the true two-group treatment was performed only in the subroutines of the ＊SIMULATE module of RFSP. This module is the appropriate one to modify first, since it is used for the tracking of reactor operating histories. The modified two-group RFSP was evaluated with true two-group cross sections from WIMS-AECL. Some tests were performed to verify the modified two-group RFSP and to evaluate the effects of fast fission and up-scatter for three core conditions and four cases corresponding to each condition. The comparisons show that the two-group results are quite reasonable and serve as a verification of the modifications made to RFSP. To assess the long-term impact of the full 2-group treatment, it is necessary to simulate a long period (several months) of reactor history. It will also be necessary to implement the full two-group treatment of reactivity devices and assess the reactivity-device worths.ce worths.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.161-168
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• 2019

The purpose of this study analyze consumer usage characteristics and product development guide of electronic pen based on TAM theory(Davies, 1989). Research methods apply contents analysis(qualitative research) and Activity/Inactivity analysis of main consumer participation. Research results are as follows. Active consumer indicated 30-49 age, male, office job and research fellow. And they suggested stable power supply system, App connected pen function extension, add the modified pen function, advanced data recognition of pen, advanced take note ability and stable grip feeling of pen, selected line width, synchronization improvement with other smart device and charging function. These result indicated the importance product improvement diffusion factor of early market to main market. The future research of electric pen focused on different product strategy between electric pen and smart device connected electric pen.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.537-546
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• 2020

This study deals with the development and improvement of a particle dispersion model for quick response to water pollutant accidents. The developed model is based on the shear dispersion theory where vertical mixing is done by step by step mixing by vertical and molecular diffusion algorithm. For the quick response to chemical accidents, an algorithm for multi-core modeling for the particle dispersion model is applied. After the application of multi-core operation using OpenMP directives to the model, the relation for the calculation time and particle size were determined along with the number of cores used for parallel programming to determine the model time for chemical accident responses. The results showed the adequate conditions for the modeling of chemical accidents for quick response and to increase the applicability of the model.

• 한국벤처창업학회:학술대회논문집
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• 2020.11a
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• pp.47-53
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• 2020

빅데이터 기술은 기업의 경쟁력을 높일 수 있는 혁신 기술 중 하나로 급성장하고 있는 가운데 농업 분야 또한 빅데이터를 활용한 경쟁력 제고와 미래 산업으로의 발전이 중요 당면과제로 부상하고 있다. 해외의 경우 농업 빅데이터를 활용한 스타트업이 빠른 속도로 증가하며 성장하는 반면 국내의 경우 생산 분야 일부 농업 벤처 외에는 빅데이터 활용이 미흡한 실정이다. 또한 기업의 빅데이터 활용수준이나 활용의도에 영향을 미치는 요인에 대한 연구가 대기업이나 특정 산업에 국한되어 이루어지고 있으며, 연구마다 영향요인 변수의 검증결과가 상이하게 나타나 산업/기업특성에 따라 연구가 필요하다. 본 연구의 목적은 농업벤처기업에서 새로운 ICT인 빅데이터를 도입하고 사용하는 데 영향을 미치는 요인을 파악하고, 이를 통해 기대하는 편익에 대해 파악함으로써 활용을 촉진할 수 있는 방안을 제시하는 데 있다. 본 연구는 빅데이터가 조직의 프로세스를 변화시키고, 최고경영층의 지원이 필수적이며, 기업이 처한 환경적 압박에 대응할 수 있는 수단으로 보고 기술·조직·환경(TOE: Technology-Organization-Environment) 프레임워크를 기반으로 혁신확산이론(Diffusion of Innovation Theory) 모형을 결합하여 본 연구에 적합한 변수들을 도출한 후 이들 변수간의 인과관계를 설정하여 연구모형을 구성하였다. 이에 따라 TOE모형의 기술적 요인에 관한 변수로는 혁신확산이론 변수인 상대적이점, 호환성, 복잡성을 채택하였고, 조직적 요인에 관한 변수로 최고경영층 지원, 비용부담능력을, 환경적 요인에 관한 변수로는 법적·정책적 지원, 경쟁자 압력을 채택하였다. 이들 3가지 요인에 속한 7가지 변수들과 빅데이터 사용의도와 기대편익 간의 관련성, 그리고 농업벤처 사업분야의 조절효과에 대한 8개의 가설을 설정하였다. 본 연구는 실제 농업벤처기업 종사자 대상 설문을 통한 실증연구를 통해 벤처 현장에서의 빅데이터 활용수준을 높이기 위한 기술적, 조직적, 환경적 관점의 정책 개선방안을 제시하고, 생산/가공/유통 등 사업분야별 비교를 통해 영향요인의 중요도 차이를 규명해 영역별로 차별적이고 효과적인 정책 방향성을 도출하는 데 시사점을 제시하고자 한다.