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Uncertainty quantification in decay heat calculation of spent nuclear fuel by STREAM/RAST-K

  • Jang, Jaerim;Kong, Chidong;Ebiwonjumi, Bamidele;Cherezov, Alexey;Jo, Yunki;Lee, Deokjung
    • Nuclear Engineering and Technology
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    • v.53 no.9
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    • pp.2803-2815
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    • 2021
  • This paper addresses the uncertainty quantification and sensitivity analysis of a depleted light-water fuel assembly of the Turkey Point-3 benchmark. The uncertainty of the fuel assembly decay heat and isotopic densities is quantified with respect to three different groups of diverse parameters: nuclear data, assembly design, and reactor core operation. The uncertainty propagation is conducted using a two-step analysis code system comprising the lattice code STREAM, nodal code RAST-K, and spent nuclear fuel module SNF through the random sampling of microscopic cross-sections, fuel rod sizes, number densities, reactor core total power, and temperature distributions. Overall, the statistical analysis of the calculated samples demonstrates that the decay heat uncertainty decreases with the cooling time. The nuclear data and assembly design parameters are proven to be the largest contributors to the decay heat uncertainty, whereas the reactor core power and inlet coolant temperature have a minor effect. The majority of the decay heat uncertainties are delivered by a small number of isotopes such as 241Am, 137Ba, 244Cm, 238Pu, and 90Y.

A Scanning Electron Microscopic Study on the Effect of Nd:YAG Laser Irradiation on the Sclerotic Dentin (Nd:YAG레이저조사가 경화상아질에 미치는 영향에 관한 주사전자현미경적 연구)

  • Kim, Moon-Hyeon;Shin, Keum-Back
    • Journal of Oral Medicine and Pain
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    • v.24 no.4
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    • pp.397-410
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    • 1999
  • In order to obtain the basic data concerning the optimal parameters in using Nd:YAG laser as a therapeutic modality to dentinal hypersensitivity, the author prepared 3 sections of sound dentin and 10 sections of sclerotic dentin with thickness of $0.5mm{\pm}0.1mm$ from human extracted teeth of anteriors and premolars, and applied the laser energy from a fiberoptic delivered, free running, pulsed Nd:YAG laser (wavelength 1064nm, pulse duration $120{\mu}sec$, fiber diameter $320{\mu}m$) to surfaces of sound and sclerotic dentin sections for 1 second with contact/unidirectional moving mode of the fiber under speed of 3mm~4mm/sec and parameters of 0.5W/10Hz, 1.0W/10Hz, 1.5W/10Hz, 2.0W/10Hz: $62J/cm^2$, $124J/cm^2$, $187J/cm^2$, $249J/cm^2$. The author comparatively evaluated the characteristics of ultrastructural changes on surfaces of sound and sclerotic dentin sections irradiated by the pulsed Nd:YAG laser using the scanning electron microscopy. A fairly ill-defined bordered surface of partially closed and melted dentinal tubules can be seen on the scanning electron microscopic feature of the sound dentin surface irradiated by the pulsed Nd:YAG laser with energy density of $62J/cm^2$. The physical modification of sound dentin surface extensively occurred depended on the increase of energy density from $62J/cm^2$ to $124J/cm^2$, $187J/cm^2$, $249J/cm^2$. While, a fairly well-defined bordered surface of partially closed and melted dentinal tubules with thickened peritubular dentin can be seen on the scanning electron microscopic feature of the sclerotic dentin surface irradiated by the pulsed Nd:YAG laser with energy density of $62J/cm^2$. The physical modification of sclerotic dentin surface of a fairly rough, shallow depression with many cracks, thickened peritubular dentin and structureless dentinal tubules extensively occurred depended on the increase of energy density from $62J/cm^2$ to $124J/cm^2$, $187J/cm^2$, $249J/cm^2$ compared to those of sound dentin surface irradiated by the pulsed Nd:YAG laser under the same parameters. Therefore, it is recommended that the pulsed Nd:YAG laser as a therapeutic modality to dentinal hypersensitivity should be applied with the less energy density than $62J/cm^2$ on the sound dentin surface, and its energy density on the partially sclerotic dentin surface should be lower than that on the sound dentin surface to preserve tooth from unnecessary excessive structural destruction.

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Resonant Formation Rates of Muonic Molecular ion in Muon-Catalyzed Fusion (뮤온 촉매 핵융합에서 뮤온 분자 이온의 공명 형성율)

  • Im, Ki-Hak;Hong, Sang-Hee
    • Nuclear Engineering and Technology
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    • v.24 no.1
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    • pp.63-74
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    • 1992
  • The resonant formation rates of muonic molecular ion dtr in the muon-catalyzed fusion are calculated in various fuel temperatures and densities. The elastic scattering cross sections between t$\mu$ and deuterons are obtained by making use of the partial wave method. The transition property of the excited compound molecule [(dt$\mu$)dee]* derived by the impulse approximation in the form of a bound-state form factor. The radiative, Auger, and collisional deexcitations are considered as the deexcitation mechanisms of the excited dt$\mu$, and each deexcitation width is calculated as well as back decay width. The resultant reaction widths are used to calculate the formation cross sections of resonant dt$\mu$. The resonant formation rates for dt$\mu$-d and dt$\mu$-t collisions are computed as functions of fuel temperature and density. The calculations show that the resonant formation rates increase with fuel densities and have the maximum values at the particular temperatures where the relative collision energies are equal to the resonant ones.

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A Study on Behavior Pattern and Physiological Changes during Bathing and Showering (목욕 및 샤워시 행동패턴 및 생리적 변화에 대한 연구)

  • Jeong W.W.;Rhee K.;Park K.R.;Chun K.J.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.256-259
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    • 2005
  • Analysis of behavior pattern and thermal response during bathing and showering provides important fundamental data when developing an automatic bathing/showering system. The behavior pattern and physiological changes during bathing/showering were measured und analyzed for the aged male group. We recorded the volunteers showering at front, back, left and right view using four CCTV cameras in order to study the behavior pattern during showering. The photographic data were analyzed by counting the frequencies of body contact and identifying zones where hands could reach. In order to study the thermal response, we measured the blood pressure (B.P), heart rate (H.R), body temperature (B.T.), breathing rate (B.R) for the different water temperatures and the locations of immersion for the young and old age groups. The results showed that the frequencies of body contacts were varied for different body sections. Also there were some body sections where hands could not be reached because of reduced pliability and muscular strength of the aged group. But we observed rather uniform body contact frequencies when a towel was used. In partial immersion bath experiments, we observed the changes of B.P. H.R and B.T in the case of young and old age groups, and the changes were more significant in the young age group.

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Independent Cooling Controller for Temperature Control of High Strength and Atmosphere Corrosion Resisting Steel in Hot Strip Mills (고강도 내후성강의 온도제어를 위한 ICC 제어기 개발)

  • Park, Cheol Jae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.3
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    • pp.327-335
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    • 2015
  • In this paper, we propose an independent cooling control (ICC) scheme for high strength and atmosphere corrosion resisting steel to obtain the desired temperature and properties along the longitudinal direction of the steel in the run-out table (ROT) process. A temperature model of the independent process is developed to divide the ROT into front and back sections. The control concept uses field data, problem analysis, and a time-temperature transformation diagram. The effectiveness of the proposed control is verified using simulation results under a temperature disturbance by the transformation in the middle of the ROT. The results of a hot strip mill field test show that the temperature control performance is significantly improved by the proposed control scheme.

A Comparative Study on the Tailored Collar Patterns of Women's Jackets - Focus on Clothing Construction Textbooks - (여성복 테일러드 칼라 패턴 비교연구 - 의복구성학 교재를 중심으로 -)

  • Jeong, Hwa-Yeon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.4
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    • pp.617-627
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    • 2010
  • This study selected and compared 7 tailored collar making factors from 15 clothing construction university textbooks. According to the results, in 15 clothing construction textbooks, the neckline of a tailored collar was drawn at the same length as the back neck circumference of the bodice and the length of collar stand was 3cm in 10 textbooks. In addition, the length of the collar laying varied between 2cm and 4.5cm regardless of the width of the upper collar or the textile thickness. In 7 out of the 15 textbooks, the gorge line of the collar was drawn by illustrating the collar pattern on the bodice based on the roll line and then copying it symmetrically. On the other hand, the pattern of upper collar was made in 5 ways; and 2 books did not give any explanation in the sections dealing with patterns or sewing. In addition, 6 textbooks explained that inner and outer collars are sewn with a difference. The lapel pattern of the facing part was made in 4 ways; in addition, 3 textbooks did not provide an explanation and 4 books explained that the difference is given in the sewing. The textile thickness and elasticity need to be considered in collar pattern making; however, they were not specifically mentioned in most of the textbooks.

Numerical Investigation of the Effects of an Orifice Inlet on the Performance of an Ejector (Orifice Inlet효과에 의한 이젝터 성능에 관한 수치해석적 연구)

  • Lijo, Vincent;Kim, Heuy-Dong;Setoguchi, Toshiaki
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.11a
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    • pp.318-322
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    • 2009
  • Supersonic ejectors are simple mechanical components, which generally perform mixing and/or recompression of two fluid streams. Ejectors have found many applications in engineering. In aerospace engineering, they are used for altitude testing of a propulsion system by reducing the pressure of a test chamber. It is composed of three major sections: a vacuum test chamber, a propulsive nozzle, and a supersonic exhaust diffuser. This paper aims at the improvement of ejector-diffuser performance by focusing attention on reducing exhaust back flow into the test chamber, since alteration of the backflow or recirculation pattern appears as one of the potential means of significantly improving low supersonic ejector-diffuser performance. The simplest backflow-reduction device was an orifice plate at the duct inlet, which would pass the jet and entrained fluid but impede the movement of fluid upstream along the wall. Results clearly showed that the performance of ejector-diffuser system was improved for certain a range of system pressure ratios, where as there was no appreciable transition in the performance for lower pressure ratios and the orifice plate was detrimental to the ejector performance for higher pressure ratios. It is found that an appropriately sized orifice system should produce considerable improvement in the ejector-diffuser performance in the intended range of pressure ratios.

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지체장애자(肢體障碍者)의 체형(體刑)에 관한 연구(硏究) - 편마비자(片麻痺者)의 동상부(胴上部)를 중심(中心)으로

  • Son, Mi-Suk;Sim, Bu-Ja
    • Journal of the Korean Society of Costume
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    • v.14
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    • pp.199-208
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    • 1990
  • In order to eximine the body form of the physically handicapped people, the 11 items of angle, 54 items of size and weight of the subjects were measured body silhouetter photographs and with the Martin's anthrophometeric instrument respectively. The subjects were consist of 37 boy students who are 13-19 years old and hemiplegias caused by cerebral palsy. And then the comparison between normal and paralysis sides, analysis of somatotypes with the body silhouetter photographs, ANOVA for effect of somatotype on measuring items for angles, and factor analysis for all items were carried out. The results were as follows: 1. The results of measuring are difference between normal and paralysis sides. 2. The items shown significant differences between normal and paralysis sides are diagonal anterior chest B, scapula length, armscye girth, diagonal posterior chest A, and arc of the bust. 3. The percentage of each somatotype shows the order of bending somatotype, turning over somatotype, turning over-bending somatotype, and standard somatotype in the upper body. There are significant differences between somatotypes and sternalis up, sternalis down, scapula, vertebialis, ${\alpha}$, and ${\beta}$ angles respectively. 4. From the result of factor analysis, front and back sections, length items of the upper part and the lower part from the bust line, and the upper size items at the bottom of armscye were abstracted.

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Gnathostoma hispidum Infection in a Korean Man Returning from China

  • Kim, Han-Seong;Lee, Jin-Joo;Joo, Mee;Chang, Sun-Hee;Chi, Je-G.;Chai, Jong-Yil
    • Parasites, Hosts and Diseases
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    • v.48 no.3
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    • pp.259-261
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    • 2010
  • Human Gnathostoma hispidum infection is extremely rare in the world literature and has never been reported in the Republic of Korea. A 74-year-old Korean man who returned from China complained of an erythematous papule on his back and admitted to our hospital. Surgical extraction of the lesion and histopathological examination revealed sections of a nematode larva in the deep dermis. The sectioned larva had 1 nucleus in each intestinal cell and was identified as G. hispidum. The patient recalled having eaten freshwater fish when he lived in China. We designated our patient as an imported G. hispidum case from China.

Flow Control in the Vacuum-Ejector System (진공 이젝터 시스템의 유동 컨트롤)

  • Lijo, Vincent;Kim, Heuy-Dong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.05a
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    • pp.321-325
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    • 2010
  • Supersonic ejectors are simple mechanical components, which generally perform mixing and/or recompression of two fluid streams. Ejectors have found many applications in engineering. In aerospace engineering, they are used for altitude testing of a propulsion system by reducing the pressure of a test chamber. It is composed of three major sections: a vacuum test chamber, a propulsive nozzle, and a supersonic exhaust diffuser. This paper aims at the improvement of ejector-diffuser performance by focusing attention on reducing exhaust back flow into the test chamber, since alteration of the backflow or recirculation pattern appears as one of the potential means of significantly improving low supersonic ejector-diffuser performance. The simplest backflow-reduction device was an orifice plate at the duct inlet, which would pass the jet and entrained fluid but impede the movement of fluid upstream along the wall. Results clearly showed that the performance of ejector-diffuser system was improved for certain a range of system pressure ratios, whereas the orifice plate was detrimental to the ejector performance for higher pressure ratios. It is also found that there is no change in the performance of diffuser with orifice at its inlet, in terms of its pressure recovery. Hence an appropriately sized orifice system should produce considerable improvement in the ejector-diffuser performance in the intended range of pressure ratios.

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