• 대한토목학회논문집
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• 제6권2호
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• pp.1-15
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• 1986

본(本) 연구(硏究)에서는 전(全) 해석과정(解析過程)을 two-Levels로 나누었다. Level 1 에서는 two-phases로 나누어 단면(斷面)을 최적화(最適化)하고, Level 2 에서는 트러스의 절점좌표(節點座標)를 변수(變數)로 하여 형상(形狀)을 최적화(最適化)하는 알고리즘을 제시(提示)한 것이다. 이 알고리즘의 Level 1 에서는 유도(誘導)된 비선형계획문제(非緣形計劃問題)를 SUMT 문제(問題)로 변환(變換)시켜 Modified Newton-Raphson Method에 의한 SUMT 법(法)을 채택하고, Leve1 2 에서는 Powell Method의 일방향(一方向) 탐사기법(探査技法)에 의해 목적함수(目的凾數)만이 최소(最小)가 되도록 하는 기법(技法)을 도입하여 최적화(最適化)알고리즘을 제시(提示)하였다. 제시(提示)된 알고리즘을 트러스의 형태(形態), 설계제약조건(設計制約條件), 재하조건(載荷條件) 등을 변화(變化)시켜 가면서 수종의 트러스에 적용(適用)하여 수치계산(數値計算)을 실시하고, 그 결과(結果)를 다른 알고리즘의 결과(結果)와 비교(比較)하므로서 알고리즘의 타당성(妥當性), 안전성(安全性), 적용성(適用性)을 검토하였다. 연구결과(硏究結果)의 two-Level 알고리즘은 트러스의 설계조건(設計條件)에 구애받지 않고 트러스의 형상최적화(形狀最適化)에 적용(適用)할 수 있으며, 안정성(安定性) 있게 비교적(比較的) 빠른 속도(速度)로 최적해(最適解)에 수렴(收斂)한다는 사실이 확인되었다.

• 척추신경추나의학회지
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• 제14권2호
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• pp.113-122
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• 2019

Objectives : The purpose of this clinical study was to evaluate the effect of spinal decompression with Korean medicine treatment on the herniation of an intervertebral disc (HIVD) in a patient after fusion surgery of a cervical segment. Methods : A single patient was treated with spinal decompression, acupuncture, pharmacoacupuncture, and herbal medication. We measured the Numerical Rating Scale (NRS), Neck Disability Index (NDI), European Quality of Life-5 Dimension (EQ-5D), Cervical Range of Motion (cervical ROM) and the Beck Depression Inventory (BDI) score to evaluate the treatment effects. Results : The patient's post neck pain & pain in both arms improved significantly as suggested by the scores on the NRS, NDI, EQ5D, cervical ROM and BDI. Conclusions : Thus, spinal decompression, including Korean medicine treatment, could be taken into consideration for HIVD patients after fusion surgery.

• 대한기계학회논문집A
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• 제34권4호
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• pp.487-493
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• 2010

대부분의 구조해석 문제는 외부에서 주어진 하중에 대한 변형과 응력에 관심을 두고 있지만 많은 경우에서 표면 또는 내부에 주어진 응력이나 트랙션을 구하는 역문제 해석이 필요하게 된다. 본 연구에서는 구하고자 하는 트랙션에서 멀리 떨어진 영역의 변위를 측정하여 미지의 트랙션을 평가하는데 유한요소법을 사용한 역문제 수식화를 적용하였다. 일반적으로 역시스템의 불안정으로 인하여 측정 변위의 작은 오차는 해석 결과에 큰 영향을 주게 된다. 이와 같은 역시스템의 불안정성을 개선하기 위하여 본 연구에서는 구하고자 하는 트랙션에 가까운 단면의 변위를 Gram-Schmidt 수직화 기법을 통한 수직기저함수 사용하여 예측하고 보다 안정된 역문제를 해석하는 방법을 개발하였고 장점들을 수치 예제를 통하여 보여주었다.

• 한국터널지하공간학회 논문집
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• 제9권1호
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• pp.83-89
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• 2007

터널 굴착은 응력해방을 발생시키기 때문에 연약한 지반에서의 터널 굴착 시에는 막장의 안정성 확보가 무엇보다도 중요한 사안으로 대두되고 있다. 이에 대한 대책 공법 중 굴착대상 막장면을 일정한 강성을 가진 강봉이나 유리섬유 파이프를 이용하여 선행 보강하는 페이스 볼트 공법이 적용되고 있다. 본 연구에서는 이러한 페이스 볼트를 이용한 막장 보강공법의 적용성을 검토하기 위해 페이스 볼트 공법이 필요한 연약한 지반에서 타설 되는 볼트의 개수를 0, 20, 40, 60, 80, 100개의 6가지 Case와 길이를 0.5D (2가지), 1.0D, 1.5D, 2.0D의 5가지 Case에 관하여 $FLAC^{3D}$ Ver.2.1을 이용해 3차원 연속체 해석을 실시하였다.

• Earthquakes and Structures
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• 제18권4호
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• pp.467-480
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• 2020

Concrete rectangular liquid storage tanks are widely used, but there are many cases of damage in previous earthquakes. Nonlinear fluid-structure interaction (FSI) is considered, Mooney-Rivlin material is used for rubber bearing, nonlinear contact is used for sliding bearing, numerical calculation models of no-isolation, rubber isolation, sliding isolation and hybrid isolation concrete rectangular liquid storage tanks are established; dynamic responses of different structures are compared to verify the effectiveness of isolation methods; and influences of earthquake amplitude, bidirectional earthquake and far-field long-period earthquake on dynamic responses are investigated. Results show that for liquid sloshing wave height, rubber isolation cause amplification effect, while sliding isolation and hybrid isolation have reduction effect; displacement of rubber isolation structure is much larger than that of sliding isolation with limiting-devices and hybrid isolation structure; when PGA is larger, wall cracking probability of no-isolation structure becomes larger, and probability of liquid sloshing wave height and structure displacement of rubber isolation structure exceeds the limit is also larger; under bidirectional earthquake, occurrence probabilities that liquid sloshing wave height and structure displacement of rubber isolation structure exceed the limit will be increased; besides, far-field long-period earthquake mainly influences structure displacement and liquid sloshing wave height. On the whole, control effect of sliding isolation is the best, followed by hybrid isolation, and rubber isolation is the worst.

• 대한암한의학회지
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• 제19권1호
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• pp.61-68
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• 2014

Objectives : To study the effect of SB injection on tumor size in an advanced non-small cell lung cancer patient. Methods : A patient was clinically diagnosed as advanced non-small cell lung cancer (Stage IIIa). Four cycles of intravenous SB injection were conducted. Each cycle lasted 4 days. The content of 7vials SB was injected every day. To compare the tumor size before treatment and after four cycles of SB injection, chest computed tomography (CT) was performed. Results : Follow-up CT images showed that the tumor size was reduced. In admission, size of the tumor $6.7{\times}8.5{\times}9.5cm$ on the left lower lobe of lung. After SB injection, size of the tumor $5.6{\times}6.8{\times}8.4cm$ by Chest CT. The patient's symptoms such as cough, sputum were improving until four cycles of SB injection. Numerical rating scale (NRS) showed improvement of Chest pain from point 3 to point 0. Conclusions : This case study suggests that intravenous SB injection may have significant effects of anti-tumor for non-small cell lung cancer.

• Journal of Oral Medicine and Pain
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• 제40권2호
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• pp.63-71
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• 2015

Purpose: To investigate the relationship between headache and sleep by evaluating sleep quality, daytime sleepiness, and specific features related to sleep-disordered breathing (SDB). Methods: One hundred one subjects with headache and 118 healthy controls were enrolled. To collect various information on headache attacks, headache group completed self-reported questionnaire about the characteristics of headache attacks and the migraine disability assessment (MIDAS) questionnaire. The subjective quality of sleep was evaluated in all of the subjects using the Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS). In addition, the following specific features of sleep were evaluated in 28 subjects selected randomly from each group: apnea-hypopnea index (AHI), prevalence of SDB, nocturnal oxygen saturation (SaO2), and oxygen desaturation index (ODI) as measured using a portable monitoring device. Results: The global PSQI and the prevalence of poor sleeping (global PSQI >5), ESS scores and the prevalence of daytime sleepiness (ESS score >10) were significantly higher in the headache group (both p<0.0001, respectively). The mean scores on the numerical rating scale and the MIDAS were significantly higher in the poor-sleeper group than in the good-sleeper group (p=0.0347 and p=0.0016, respectively). The global PQSI and prevalence of daytime sleepiness were significantly higher in the chronic-headache group than in the acute-headache group (p=0.0003 and p=0.0312, respectively). Conclusions: There is a significant association between headache and sleep. Especially, severity and chronicity of headache were significantly associated with sleep quality and daytime sleepiness.

• Journal of Oral Medicine and Pain
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• 제39권3호
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• pp.96-99
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• 2014

Purpose: The objective of this retrospective pilot study was to evaluate the effectiveness of Gabapentin in patients with primary burning mouth syndrome (BMS). Methods: Ten subjects were diagnosed with primary BMS (8 women and 2 men). The mean age was 60.1 years. They had clinical examination to exclude local factors such as the presence of Candida species, xerostomia, lichen planus, etc. They also underwent hematological examination to exclude secondary BMS due to systemic disorders. Pain was assessed by patients on an 11-point numerical rating score system (0 to 10). Gabapentin was administered at a starting dose of 300 mg/day, slowly titrated up to maximum of 1,800 mg/day. All patients were treated for 4 weeks. Results: One half of the patients (n=5) obtained reduction in pain over the treatment period. Four patients reported no reduction in pain symptoms. One patient reported that symptoms were worsening. The average pain score before the treatment was 6.3 and after the treatment was 5.25. No significant relationship was detected between pretreatment and posttreatment pain score. Only one patient noted mild side effect (dizziness). Conclusions: This retrospective pilot study provides no preliminary evidence that Gabapentin has effect in the management of BMS. However, further research (well-designed, randomized, and controlled trial with large sample) would be needed to investigate the efficacy of Gabapentin in treatment of BMS.

• Journal of Oral Medicine and Pain
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• 제44권4호
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• pp.160-168
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• 2019

Purpose: To search the salivary factors that objectively indicate an pain in myalgia patients with temporomandibular joint disorder (TMD) and determine the possibility of the factors as pain-biomarkers. Methods: Participants consisted of pain-free 15 persons (male 7, female 8, mean age±standard deviation (SD); 26.8±16.04 years) and 45 myalgia patients with TMD (male 21, female 24, mean age±SD; 27.98±13.01 years). They were divided into a pain-free group (numerical rating scale [NRS] score 0), a mild pain group (NRS 1-4), a moderate pain group (NRS 5-6), and a severe pain group (NRS 7-10) and members of all groups were age, sex matched. Interleukin-8 (IL-8) and matrix metalloprotease 9 (MMP-9) were selected as pain biomarkers, by searching the Gene Expression Omnibus database and analyzing pain-related genes. Enzyme-linked immunosorbent assays were used to measure the concentration of IL-8 and MMP-9 in the patients' saliva. Results: IL-8 and MMP-9 levels were statistically significantly higher in pain groups than in the pain-free group. Greater differences were observed in patients with acute pain (with painful duration under 3 months) than in the control group and in female patients than in male. Conclusions: Salivary IL-8 and MMP-9 may play a role as biomarkers of myalgia in patients with TMD.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 추계공동학술대회논문집
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• pp.139-145
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• 2002

수로에서의 선박통항으로 인해 주변환경 렌 구조물에 미치는 영향을 평가하기 위하여 선박의 추진기로 인한 흐름을 다루었다. 제한수로에서의 수치모델은 Shield's diagram과 추진기의 운동량 이론을 사용하여 개발하였다. 프로펠러에 의한 추진기방정식은 분사를 정의하는 가장 정확한 수단으로 분사계수와 분사유속을 기초로 하여 수립하였다 추진기분사에 대해 접근한 방법은 적용 선박의 출력에 기초하였으며, 추진기 분사방정식의 주요함수에는 추진력, 프로펠러 직경, 그리고 선박의 속도를 도입하였다. 또한, 수로의 수심과 선박의 홀수도 초기이동한계입경의 계산에 필요하다. 추진기로부터 분사된 유속의 분포는 Gaussian 정규분포함수로 나타내었다 저면마찰속도와 진단응력은 Sternberg 공식으로부터 유도되었으며, 아울러 선박 추진기로 인해 수로저면에서 표사이동에 현저한 영향을 미치는 경우를 사례연구를 통해서 나타내었다.