• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.38-38
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• 2023

Pleikrong reservoir with a concrete gravity dam that impound more than 1 billion cubic meter storage volume is one of the largest reservoir in Central Highland of Vietnam. Sedimentation is a major problem in this area and it becomes more severe due to the effect of climate change. Over time, it gradually reduces the reservoir storage capacity affecting to the reliability of water and power supply. This study aims to integrate the soil and water assessment tool (SWAT) model with 14 bias-corrected GCM/RCM models under two emissions scenarios, representative concentration pathway (RCP) 4.5 and 8.5 to estimate sediment inflow to Pleikrong reservoir in the long term period. The result indicated that the simulated total amount of sediment deposited in the reservoir from 2010 to 2018 was approximately 39 mil m³ which is a 17% underestimate compared with the observed value of 47 mil m³. The results also show the reduction in reservoir storage capacity due to sedimentation ranges from 25% to 62% by 2050, depending on the different climate change models. The reservoir reduced storage volume's rate in considering the impact of climate change is much faster than in the case of no climate change. The outcomes of this study will be helpful for a sustainable and climate-resilient plan of sediment management for the Pleikrongreservoir.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.311-312
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• 2023

In this study, porous concrete with improved functionality was developed by using superabsorbent polymer (SAP) to provide rooting space for plants. The depth of settlement and mass change according to the substitution and addition rate of SAP were determined by investigating the functional performance of SAP and the volume change upon saturation. Test results indicated the depth of penetration settlement increased as the substitution rate of SAP increased, but the mass change could not be confirmed as the addition rate of SAP increased. The instability of the specimens due to the excessive volume change of SAP, as well as the osmotic pressure phenomenon according to the pH concentration, were identified as the cause. Therefore, future studies are needed to investigate the appropriate substitution and addition rate of SAP, as well as to reduce the osmotic pressure phenomenon according to the pH concentration, which would contribute to the improvement of the functional performance of vegetation concrete.

• 대한영상의학회지
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• 제82권6호
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• pp.1534-1544
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• 2021

목적 전산화단층촬영에서 호흡에 의한 폐 용적의 변화가 폐 반고형결절의 크기와 용적에 미치는 영향을 알아보고자 한다. 대상과 방법 총 31명의 환자에서 42개의 반고형결절이 연구에 포함되었다. 먼저 총 폐활량 상태에서 전산단층화촬영을 시행 받은 후, 결절이 포함된 부분만 일호흡용적 상태에서 추가로 촬영하였다. 각각의 반고형결절의 직경과 용적을 측정하였고, 전체 폐 용적은 결절의 중심이 있는 동측 폐의 단면적으로 추정하였다. 동일한 개인 내에서 총 폐활량과 일회 호흡량 간 측정값 변화의 유의성을 통계적으로 평가하였다. 결과 총 폐활량 상태와 비교하였을 때, 일회 호흡용적 상태에서 폐 단면적은 평균 12.7 cm², 반고형결절의 직경 및 용적은 평균적으로 각각 0.5 mm와 46.4 mm³ 감소하였다(p < 0.001). 총 폐활량 상태와 일호흡량 상태 간 폐 면적 변화는 반고형결절의 직경 변화(rho = 0.341; p = 0.027) 및 부피 변화(rho = 0.401; p = 0.014)와 유의한 양의 상관관계를 보였다. 그러나 폐 용적의 변화를 고려하여 보정한 후에는 반고형결절의 평균 직경과 부피가 총 폐활량 상태와 일호흡량 상태 간 유의한 차이가 없었다(각각 p = 0.062, p = 0.124). 결론 전산화단층촬영에서 측정한 반고형결절의 크기와 용적은 동일한 환자 내에서도 촬영 당시의 폐 용적에 유의한 영향을 받는다.

• 대한후두음성언어의학회지
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• 제15권1호
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• pp.5-9
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• 2004

Some patients who have undergone adenotonsillectomy (AT) or tonsillectomy(T) complain of voice change. Research was designed to determine the relationship between subjective voice change and change of parameters in boice analysis and to find the degree of voice change according to age and excised tissue volume. In 34 patients who underwent AT and 17 patients who underwent T, we measured the masalance, the fundamental frequency of /a/phonation and the formants and bandwidths of /a/, /i/, /u/ phonations. These parameters were measured preoperatively and also 7 days after the operation. Excised tissue volume was measured on operation. Postoperative changes were statistically analyzed. Any subjective voice change was asked to be reported at the visit 7 days after the operation. There was analysis for the difference of above parameters between some who answered "voice change" (A group) and the others who answered "no voice change" (B group). 24 patients(71%) who underwent AT and 4 voice change. Nasals nasalance change is an important factor in subjective voice change after AT.

• Journal of Korean Neurosurgical Society
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• 제42권4호
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• pp.286-292
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• 2007

Objective : Gamma Knife Stereotactic Radiosurgery (GK SRS) has become an important treatment modality for vestibular schwannomas. We evaluated the tumor control rate, patterns of tumor volume change and preservation of hearing following low-dose radiation for vestibular schwannomas in a homogeneous cohort group in which the mean marginal dose was 12 Gy. Methods : A total of 59 patients were enrolled in this study. All enrolled patients were followed-up for at least 5 years and the radiation dose was 11-13 Gy. Regular MRI, audiometry and clinical evaluations were done and tumor volumes were obtained from MRI using the OSIRIS program. Results : The tumor control rate was 97%. We were able to classify the patterns of change in tumor volume into three categories. Transient increases in tumor volume were detected in 29% of the patients and the maximum transient increase in tumor volume was identified at 6 to 30 months after GK SRS. The transient increases in tumor volume ranged from 121% to 188%. Hearing was preserved in 4 of the 12 patients who had serviceable hearing prior to treatment. There were no other complications associated with GK SRS. Conclusion : Low-dose GK SRS was an effective and safe mode of treatment for vestibular schwannomas in comparison to the previously used high-dose GK SRS. Transient increases in tumor volume can be identified during the follow-up period after low-dose GK SRS for vestibular schwannomas. Physicians should be aware that these increases are not always indicative of treatment failure and that close observation is required following treatments. Unfortunately, a satisfactory hearing preservation rate was not achieved by reducing the radiation dose. It is thought that hearing preservation is a more sophisticated problem and further research is required.

• 한국식품조리과학회지
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• 제20권4호
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• pp.396-402
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• 2004

증편의 sponge상의 망상구조에 쌀 단백질의 영향을 조사하기 위하여 증편제조시 주원료인 쌀 단백질을 분리하고 증편 발효시 그 변화를 살펴보았으며 protease 첨가가 증편의 점도 및 부피에 미치는 영향을 살펴보았다. 또한 쌀 전분에 단백질을 첨가하여 증편의 점도 및 부피에 미치는 영향을 살펴본 결과 쌀 단백질이 증편의 부피 팽창에 영향을 주는 것으로 생각되었다. 쌀 및 증편 반죽에서는 SDS 가용성 단백질 함량이 밀가루와 비교해 높게 나타났으며 발효시간에 따른 단백질 추출량은 큰 변화가 없었다. 그러나 증편반죽의 시간별 FPLC패턴은 발효시간에 따라 저분자 peak가 감소하여 고분자화함을 알 수 있었다. 단백질 분해효소 protease를 첨가하여 본 결과 증편의 점도 및 부피는 현저히 감소하였고 쌀 전분에 단백질을 첨가하여 증편을 재구성한 결과, 점도, 부피는 증가하는 것으로 나타나 증편내에서 쌀 단백질이 증편의 부피 내지는 조직감 형성에 크게 영향을 미치는 것으로 생각되어진다.

• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.119-130
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• 2002

The purpose of this study was to evaluate hemodynamics of intracranial blood flow for obtain clinically useful reference values and assess cerebral hemodynamics change with aging. 81 normal Korean subjects(age, 14$\thicksim\∼\thicksim$70 years) examined who han no history of neurologic disease and the subjects divided into group A(age, 14$\∼$39 years), group B(age, 40$\∼$59 years) and group C(age, 60$\∼$70 years). Transcranial doppler was use for measured the maximum velocity(Vmax), mean velocity(Vmean), pulsatility index(PI), resistive index(RI), stenosis index(SI) and depth of sample volume. Vmax was 99.1 1cm/s, Vmean was 63.57cm/s, PI was 0.85, RI was 0.56, SI was 31.94 and depth of sample volume was 52.35 in middle cerebral artery. Vmax was 85.54cm/s, Vmean was 52.52cm/s, PI was 0.82, RI was 0.55, SI was 34.48 and depth of sample volume was 73.62 in anterior cerebral artery. Vmax was 75.45cm/s, Vmean was 45.60cm/s, PI was 0.82, RI was 0.58, SI was 36.14 and depth of sample volume was 62.35 in posterior cerebral artery. Vmax was 70.44cm/s, Vmean was 47.07cm/s, PI was 0.87, RI was 0.58, SI was 29.83 and depth of sample volume was 75.23 in basilar artery Vmax was 63.92, Vmean was 42.42, PI was 0.89, RI was 0.58, SI was 29.89 and depth of sample volume was 66.65 in vertebral artery. Vmax and Vmean was significantly decreased with increasing age in middle cerebral artery, anterior cerebral artery, posterior cerebral artery, basilar artery and vertebral artery And PI and RI was significantly increased with increasing age in basilar artery and vertebral artery. And I suggest that transcranial doppler sonography can be used as one of useful clinical tool for detection of cerebral hemodynamics.

• Archives of Plastic Surgery
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• 제46권2호
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• pp.135-139
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• 2019

Background In immediate breast reconstruction using an extended latissimus dorsi musculocutaneous (eLDMC) flap, the volume of the flap decreases, which causes a secondary deformity of the breast shape. Since little research has investigated this decrease in muscle volume, the authors conducted an objective study to characterize the decrease in muscle volume after breast reconstruction using an eLDMC flap. Methods Research was conducted from October 2011 to November 2016. The subjects included 23 patients who underwent mastectomy due to breast cancer, received immediate reconstruction using an eLDMC flap without any adjuvant chemotherapy or radiotherapy, and received a computed tomography (CT) scan from days 7 to 10 after surgery and 6 to 8 months postoperatively. In 10 patients, an additional CT scan was conducted 18 months postoperatively. Axial CT scans were utilized to measure the volumetric change of the latissimus dorsi muscle during the follow-up period. Results In the 23 patients, an average decrease of 54.5% was observed in the latissimus dorsi muscle volume between the images obtained immediately postoperatively and the scans obtained 6 to 8 months after surgery. Ten patients showed an average additional decrease of 11.9% from 6-8 months to 18 months after surgery. Conclusions We studied changes in the volume of the latissimus dorsi muscle after surgery using an eLDMC flap performed after a mastectomy without adjuvant chemotherapy or radiotherapy. In this study, we found that immediate breast reconstruction using a latissimus dorsi muscle flap led to a decrease in muscle volume of up to 50%.

• Nuclear Engineering and Technology
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• 제24권1호
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• pp.40-51
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• 1992

연구용 원자로의 분산형 핵연료에 대한 노내 조사 거동의 주요 특성중의 하나는 핵연료심 팽윤에 기인된 핵연료봉 직경 증가이다. 본 논문에서는 분산형 우라늄실리사이드 핵연료에 대한 노내 조사거 동과 실험 증거들을 분석함으로써 그 핵연료의 팽윤에 대한 물리적 해석 모형인, DFSWELL 전산 모형을 개발하였다. 문헌에 보고된 실험 증거들로부터 노내에서 U$_3$Si-Al 핵연료심의 부피변화는 온도와 핵분열율에 따라 크게 영향을 받는 것으로 나타났다. 분산형 우라늄 실리사이드 핵연료에 대한 정량적 팽윤량은 주어진 온도, 핵분열율, 핵분열고체생성물 측적 및 핵분열기체 기포거동을 고려함으로써 평가될 수 있다. 연구로의 분산형 우라늄실리사이드 핵연료의 팽윤 현상은 다음과 같은 세 가지 현상으로 귀결된다. i ) 핵분열기체생성물 기포 생성/축적에 치한 부피변화 ii ) 고체 핵분열생성물의 축적 및 상 변화에 의한 부피변화 iii ) 핵연료 입자와 기지 사이의 공유층에 대한 부피변화 상기 세 가지의 물리 적 현상을 고려하는 본 DFSWELL 전산 모형의 출력이력 조건에 따른 절대 예측치들은 실행 결과와 비교할 때 분산형 우라윰실리 사이드 핵연료의 조사추 팽윤 실측치와 잘 일치한다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제21회 KOSCO SYMPOSIUM 논문집
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• pp.212-216
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• 2000

Combustion phenomenon in scale-downed combustor is investigated. As the combustor volume decreases surface to volume ratio increases. for increased surface to volume ratio means increased heat loss and this increased heat loss affects reaction in combustion chamber. Plastic mini combustor is made. Stoichiometricaly premixed Hydrogen I air gas is used as fuel. Initial chamber pressure and chamber size are varied and the effects are evaluated. Peak pressure decreases with the decrease in chamber height. As initial chamber pressure decreases peak pressure decreases. And this change is more important than scale down effect till the chamber height of 1mm. With this result and further information following the experiments design parameter for micro engine can be established.