• Nuclear Engineering and Technology
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• 제56권2호
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• pp.359-374
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• 2024

A high-fidelity numerical analysis methodology was proposed for evaluating the fuel rod cladding integrity of a Prototype Gen IV Sodium Fast Reactor (PGSFR) during normal operation and Design basis events (DBEs). The MARS-LMR code, system transient safety analysis code, was applied to analyze the DBEs. The results of the MARS-LMR code were used as boundary condition for a 3D computational fluid dynamics (CFD) analysis. The peak temperatures considering HCFs satisfied the cladding temperature limit. The temperature and pressure distributions were calculated by ANSYS CFX code, and applied to structural analysis. Structural analysis was performed using ANSYS Mechanical code. The seismic reactivity insertion SSE accident among DBEs had the highest peak cladding temperature and the maximum stress, as the value of 87 MPa. The fuel cladding had over 40 % safety margin, and the strain was below the strain limit. Deformation behavior was elucidated for providing relative coordinate data on each active fuel rod center. Bending deformation resulted in a flower shape, and bowing bundle did not interact with the duct of fuel assemblies. Fuel rod maximum expansion was generated with highest stress. Therefore, it was concluded that the fuel rod cladding of the PGSFR has sufficient structural safety margin during DBEs.

• 대한후두음성언어의학회지
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• 제12권1호
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• pp.11-16
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• 2001

Background and Objectives : A burn injury to the glottis differs from a burn injury to the trachea, bronchi, and lung parenchyma, in that thermal injury does not occur to any significant degree below the level of the larynx, due to the effective cooling of air by the upper airway and to reflex closure of the vocal cords from a blast of hot air. Therefore, the laryngeal inhalation injury give rise to airway problem and voice change. The objectives of this study is to assess management of laryngeal inhalation injury and voice change after management. Materials and Methods : Voice choses and laryngeal injuries of eight laryngeal inhalation patients were analyzed through questionnaire, voice dynamic laboratory, and laryngeal stroboscopy. Operative management was performed to five patients for airway patiency and vocal cord movement on laryngeal pathology ind voice therapy was performed to all patients. One-year after, voice changes and laryngeal injuries were reanalyzed with same methods. Results : Vocal breathiness, decreased voice intensity, reduced voice range, and easy fatigability were major complaints of laryngeal inhalation patients. Glottic stenosis were developed to five of eight patients, and vocal cord atrophy, bowing were developed to others. Vocal cord mucosal waves were significantly decreased in all patients. Jitter(%), Shimmer(dB) were increased and Maximal phonation time(MPT) was decreased. One-year after, subjective voice changes and objective voice parameters were improved. And vocal cord mucosal waves were recovered in all patients. Conclusions : Subjective voice quality and objective voice parameters were improved after operative management for laryngeal pathology and voice therapy. And we observed recovery of vocal fold mucosal waves by laryngeal stroboscopy. We think that early preventable tracheotomy is necessary to reduce the laryngeal contact injury in laryngeal inhalation patients.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.61.1-61.1
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• 2015

Nanoscale semiconductor plasma processing has become one of the most challenging issues due to the limits of physicochemical fabrication routes with its inherent complexity. The mission of future and emerging plasma processing for development of next generation semiconductor processing is to achieve the ideal nanostructures without abnormal profiles and damages, such as 3D NAND cell array with ultra-high aspect ratio, cylinder capacitors, shallow trench isolation, and 3D logic devices. In spite of significant contributions of research frontiers, these processes are still unveiled due to their inherent complexity of physicochemical behaviors, and gaps in academic research prevent their predictable simulation. To overcome these issues, a Korean plasma consortium began in 2009 with the principal aim to develop a realistic and ultrafast 3D topography simulator of semiconductor plasma processing coupled with zero-D bulk plasma models. In this work, aspects of this computational tool are introduced. The simulator was composed of a multiple 3D level-set based moving algorithm, zero-D bulk plasma module including pulsed plasma processing, a 3D ballistic transport module, and a surface reaction module. The main rate coefficients in bulk and surface reaction models were extracted by molecular simulations or fitting experimental data from several diagnostic tools in an inductively coupled fluorocarbon plasma system. Furthermore, it is well known that realistic ballistic transport is a simulation bottleneck due to the brute-force computation required. In this work, effective parallel computing using graphics processing units was applied to improve the computational performance drastically, so that computer-aided design of these processes is possible due to drastically reduced computational time. Finally, it is demonstrated that 3D feature profile simulations coupled with bulk plasma models can lead to better understanding of abnormal behaviors, such as necking, bowing, etch stops and twisting during high aspect ratio contact hole etch.

• 대한골관절종양학회지
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• 제2권1호
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• pp.94-100
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• 1996

Ossifying fibroma is one of a group of fibro-osseous lesions which arises typically within the jaw bones and only rarely affects the long bones. Ossifying fibroma of the long bones almost involve exclusively the tibia but may also involve the fibula. Ossifying fibroma of the long bones is distinct from fibrous dysplasia, adamantinoma and nonossifying fibroma with regard to age of the patient, site, radiographic appearance, histological features, and clinical course. We are reporting the cases of seven patients with a tumor-like lesion that named osteofibrous dysplasia. It is most commonly found in the tibia and fibula of a child ten years of age or younger. Of the seven cases reported in this study, only one patient was younger than ten years. In all cases, the lesions were usually located in the tibial diaphysis. The average duration of clinical manifestation was 5.2 years. The clinical symptoms were anterior bowing of the tibia in 2 cases, buldging of the tibia in 2 cases, and mass overlying the tibia in 3 cases. On the roentgenography, it shows multiple radiolucent lesion with intervening sclerotic rim of the tibial diaphysis. In seven patients, 6 cases were confirmed with biopsy. We had done curettage and bone graft in three cases, VFG was done in one case. The other three cases underwent conservative management.

• Journal of Korean Neurosurgical Society
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• 제55권2호
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• pp.78-82
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• 2014

Objective : To investigate a diagnostic value of ultrasonography in carpal tunnel syndrome (CTS) patients and to evaluate a correlation of sonographic measurements with the degree of electrodiagnostic abnormalities and clinical severity. Methods : Two-hundred-forty-six symptomatic hands in 135 patients and 30 asymptomatic hands in 19 healthy individuals as control group were included. In ultrasonographic study, we measured the cross-sectional area (CSA) and flattening ratio (FR) of the median nerve at the pisiform as well as palmar bowing (PB) of the flexor retinaculum. Sensitivity and specificity of ultrasonographic measurements were evaluated and ultrasonographic data from the symptomatic and control hands were compared to the grade of electrodiagnostic and clinical severity. Results : The mean CSA was $13.7{\pm}4.2mm^2$ in symptomatic hands and $7.9{\pm}1.3mm^2$ in asymptomatic hands. The mean FR was $4.2{\pm}1.0$ in symptomatic hands and $3.4{\pm}0.4$ in asymptomatic hands. The mean PB was $3.5{\pm}0.5$ mm in symptomatic hands and $2.6{\pm}0.3$ mm in asymptomatic hands. Statistical analysis showed differences of the mean CSA, FR and PB between groups were significant. A cut-off value of $10mm^2$ for the mean CSA was found to be the upper limit for normal value. Both the mean CSA and PB are correlated with the grade of electrophysiological abnormalities and clinical severity, respectively. Conclusion : Ultrasographic measurement of the CSA and PB is helpful to diagnose CTS as a non-invasive and an alternative modality for the evaluation of CTS. In addition, ultrasonography also provides a reliable correlation with the grade of electrodiagnostic abnormalities and clinical severity.

• 복식
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• 제59권3호
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• pp.96-108
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• 2009

This study is made on the royal lady's dress In late Joseon dynasty according to the King Heon-jong and Lady Kyung-bin's Wedding Diary in the year of Jung-mi(1847) and summarised as follows: Girls' full dress was a set of a red skirt, a violet undo. jacket, and a light yellow jacket and a green Gyeon-ma-gi(a kind of top jacket) with he. hair Saeng-meo-ri hanging Do-tu-rak-daeng-gi(a kind of hair ribbon). At the big ceremony, girls wore a green Dang-ui instead of Gyeon-ma-gi. A girl picked up as a royal concubine wore a green Won-sam, which was decorated with gilt letters meaning longevity, patched emblems of gilt letter meaning longevity on the breast and on the back, belted with Bong-dae(a red sash with gilt phoenexes), like a princess's full dress. At the Kyung-bin's installation of Crown Princess and her first greeting ceremony with royal elders, she wore a green Won-sam as a formal dress, which had an embroidered emblem of phoenix, the belt with crystal ornaments, Pae-ok(佩玉), Kyu(圭) of blue jade, Shou(綬) with an phoenix. At a Dong-wrae-yun(drinking ceremony after bride and bridegroom's bowing to each other), she wore the embroidered red Jang-sam as a formal dress. Kyung-bin wore a purple Won-sam with Bong-dae as a full dress for a royal feast. According to the occasions, the same dress was differentiated with ornaments and rotors. Ji-keum-bal was an attire for ordinary ceremony. The attire was equipped with a woven gold green Dang-ui with an emblem of phoenix, a blue gilt underskirt and a red gilt overskirt. No-ui was worn as outdoor clothes. Jang-sam was worn by various classes, so it was differentiated with materials and names according to her class.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.14-14
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• 2006

Al2O3 단결정을 기판을 이용하여 HVPE법으로 GaN를 성장한 후 얻어진 GaN wafer는 N-face에 동종인 GaN를 성장하였다. 이때 동종 성장은 Al2O3와의 열팽창계수 차이로 야기된 휨을 제거할 수 있었으며, 양쪽 면은 결합 밀도가 급격히 감소하였다. 또한 표면 분극을 조사하기 위하여 에칭후 SEM 형상과 CBED를 조사 하였으며 특히 N-face에서의 표면 형상과 PL의 변화를 조사하였다. 이때 N-face의 변화는 초기의 N-face의 특성과 다른 양상을 보여 주고 있으며, DXRD와 PL 분석 걸과 결정성은 두배나 높은 결과를 보여주고 있다.

• 대한소아치과학회지
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• 제32권1호
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• pp.152-157
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• 2005

Hypophosphatemia rickets는 비타민 D의 치료량에 내성을 갖기 때문에 Vitamin D-resistant rickets(VDRR)라고도 명명되며, 이는 요세관으로부터 무기질 인산의 재흡수가 감소됨으로써 혈청 칼슘농도는 정상이나 인산농도가 낮고 alkaline phosphatase가 약간 증가되기 때문에 쉽게 진단되는 구루병의 한 형태이다. 이러한 Hypophosphatemia rickets의 임상적인 소견으로 양다리가 휘는 것. 작은 키, 척추측만. 손목과 발목부위의 팽대가 나타나며 구강내 소견으로는 자발적인 치성농양의 높은 발생률, 맹출 지연, 근단공의 폐쇄지연, 얇고 저형성된 법랑질, 명확히 인지하기 힘든 치조백선, 확대된 치수강, 법랑상아경계까지 연장된 치수각 등이 있다. 본 증례는 유치의 상실과 그에 따른 치료를 위해 본원 소아과에서 의뢰된 비타민 D저항성 구루병 환아의 임상소견과 그 치과적 치료에 대해 보고하는 바이다.

• Journal of the Korean Wood Science and Technology
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• 제28권3호
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• pp.14-24
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• 2000

본 연구에서는 향후 공급량이 증가될 것으로 예상되는 라디아타소나무와 국산 낙엽송의 두 수종을 이용하여 합판을 제조하고 구조용 합판 및 콘크리트 거푸집용 합판으로서의 사용 가능성을 검토하고자 하였다. 먼저, 기초적인 재질을 평가하기 위하여 합판의 재질시험 및 못성능 등의 시험을 실시하였고, 콘크리트조 주택 혹은 목조주택 등의 구조용 재료로의 사용을 검토하기 위해 집중하중과 균일분포하중에 의한 구조성능 시험 및 콘크리트 거푸집용으로서의 성능시험을 실시하였다. 합판의 기초 재질에 해당되는 비중, 너비 굽음, 길이 굽음 비틀림에 대한 실험 결과, 구조용 재료로서의 기준을 만족하였다. 못 측면 저항력, 못 인발 저항력 그리고 못머리 관통력에 대한 실험 결과, 구조용 재료로서의 벽체나 지붕재에 대한 표준성능을 만족하였다. 이들 두 수종으로 제조한 합판의 경우, 집중하중과 균일 분포하중에 의한 구조성능 평가, 콘크리트 거푸집용으로서의 성능 평가 결과를 볼 때 구조용 덮개재, 바탕바닥 마감재, 콘크리트 거푸집용 재료로의 사용이 가능하다고 판단되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.472-472
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• 2011

The capacitive coupled plasma (CCP) has been extensively used in the semiconductor industry because it has not only good uniformity, but also low electron temperature. But CCP source has some problems, such as difficulty in varying the ion bombardment energy separately, low plasma density, and high processing pressure, etc. In this reason, dual frequency CCP has been investigated with a separate substrate biasing to control the plasma parameters and to obtain high etch rate with high etch selectivity. Especially, in this study, we studied on the etching of $SiO_2$ by using the pulse-time modulation in the dual-frequency CCP source composed of 60 MHz/ 2 MHz rf power. By using the combination of high /low rf powers, the differences in the gas dissociation, plasma density, and etch characteristics were investigated. Also, as the size of the semiconductor device is decreased to nano-scale, the etching of contact hole which has nano-scale higher aspect ratio is required. For the nano-scale contact hole etching by using continuous plasma, several etch problems such as bowing, sidewall taper, twist, mask faceting, erosion, distortions etc. occurs. To resolve these problems, etching in low process pressure, more sidewall passivation by using fluorocarbon-based plasma with high carbon ratio, low temperature processing, charge effect breaking, power modulation are needed. Therefore, in this study, to resolve these problems, we used the pulse-time modulated dual-frequency CCP system. Pulse plasma is generated by periodical turning the RF power On and Off state. We measured the etch rate, etch selectivity and etch profile by using a step profilometer and SEM. Also the X-ray photoelectron spectroscopic analysis on the surfaces etched by different duty ratio conditions correlate with the results above.