• 대한치과교정학회지
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• 제54권5호
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• pp.265-273
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• 2024

Objective: This study aimed to investigate the effects of archwire form and power arm positions on maxillary incisors during lingual en masse retraction supported by miniscrew implants, using the finite element analysis method. Methods: Sliding mechanics for lingual en masse retraction were simulated using the finite element method. Power arms were placed mesial and distal to the maxillary canine with straight and mushroom-shaped archwires. Miniscrews provided absolute anchorage for retraction force. Results: When power arms were positioned mesial to the canine teeth, an increase in the intercanine distance was observed, while a decrease was noted when the power arms were distal to the canine tooth. Lateral incisors exhibited a greater torque loss, particularly when the power arm was mesial to the canine tooth. In the central incisors, the mushroom archwire resulted in intrusion, while the straight archwire showed an extrusion tendency. Movements in groups using the straight archwire were less controlled compared to those in groups using the mushroom archwire. Conclusions: The archwire form and the position of the power arm affected the torque loss and vertical position of incisors during lingual en masse retraction supported by miniscrew implants. The most controlled movement was achieved with the combination of a power arm positioned distal to the canine tooth and a mushroom archform.

• Physical Therapy Rehabilitation Science
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• 제6권4호
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• pp.208-213
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• 2017

Objective: Despite reliable evidence of abnormal scapular motions increases, there is not yet sufficient evidence of abnormal humeral translations. This study aims to analyze the motion of the humeral head toward the scapula when the shoulder is actively abducted using the C-arm. Design: A case report. Methods: The participant was a healthy man without any limitation and pain during shoulder movement. The participant's shoulder was abducted; this movement in the frontal plane was measured using a C-arm (anterior-posterior view) and was analyzed with computer-aided design. The starting posture was $15^{\circ}$, and as the participant abducted his shoulder measurements were taken and analyzed at $30^{\circ}$, $60^{\circ}$, $90^{\circ}$, $120^{\circ}$, $150^{\circ}$, and ending at $165^{\circ}$. A line was drawn perpendicularly to the line connecting the humeral head axis to the glenoid, and another line was drawn perpendiculary to the line connecting the scapular axis to the glenoid. The distance between the two lines measured is defined as the e value. Results: At the starting posture ($15^{\circ}$), the central axis of the humeral head was located 1.92 mm inferior to the central axis of the scapula. The humeral head was superiorly translated from the starting posture to $120^{\circ}$, and then, showed an inferior translation to the ending posture ($165^{\circ}$). Conclusions: The results of this study showed that the humeral head moved upward from the starting posture ($15^{\circ}$) up to $120^{\circ}$ indicating, superior translation, and it moved downward when the posture was past $120^{\circ}$, indicating inferior translation.

• 대한기계학회논문집A
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• 제39권5호
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• pp.535-541
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• 2015

본 연구에서는 벽걸이 모니터 브라켓 암의 다중목적 근사최적설계를 수행하였다. 이를 위해 브라켓 암의 자유도를 고려하여 평면내의 회전 각도를 선정해 응력과 처짐량이 크게 발생하는 경우에 대한 최적화 문제를 정식화 하였다. 직교배열표와 반응표면법을 사용하여 평균 및 파라미터 분석을 통해 성능지수에 대한 설계변수 민감도를 확인하였으며, 중심합성계획법과 D-최적 계획법을 사용하여 목적함수와 제한조건함수에 대하여 반응표면 근사모델을 생성하고 $R^2$ 값을 통해 정확도를 평가하였다. 이를 비지배 분류 유전알고리즘에 적용하여 최적화를 수행하고 유한요소해석을 통해 검증하였다. 또한, 중심합성 계획법과 D-최적 계획법을 이용한 최적해를 비교 분석하였다.

• Journal of Gastric Cancer
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• 제22권4호
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• pp.408-417
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• 2022

Purpose: Treatment options are limited after the failure of first-and second-line treatments in patients with HER2⁺ metastatic gastric cancer (mGC). The present study aimed to explore the efficacy, safety, and prognostic factors of apatinib efficacy as a third-line therapy for patients with human epithelial growth factor receptor 2-positive (HER2⁺) mGC. Materials and Methods: A total of 59 HER2⁺ mGC patients who received apatinib as third-line therapy were retrospectively enrolled in this two-center, single-arm, cohort study; the clinical response, survival data, and adverse events were retrieved. Results: The median progression-free survival (PFS) was 5.2 months (95% confidence interval [CI], 3.9-6.5), and the median overall survival (OS) was 8.2 months (95% CI, 6.6-9.8) Furthermore, forward stepwise multivariate Cox regression analysis showed that a higher Eastern Cooperative Oncology Group performance status score and multiple metastases were independently correlated with decreased PFS and OS (both P<0.05). The main adverse events were leukopenia (45.8%), hypertension (44.1%), thrombocytopenia (39.0%), hand-foot syndrome (37.3%), and elevated transaminase (33.9%). Grade 3 adverse events mainly included hypertension (5.1%) and neutropenia (5.1%); grade 4 adverse events did not occur. Conclusions: Apatinib is efficient and well tolerated in patients with HER2⁺ mGC as a third-line treatment, suggesting that it may be a candidate of choice for these patients.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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• pp.787-796
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• 1995

A man model is a useful design tool for the evaluation of man machine systems and products. An arm reach trajectory prediction for such a model will be specifically useful to present human activities and, consequently, could increase the accuracy and reality of the evaluation. In this study, a three-dimensional reach trajectory prediction model was developed using an inverse kinematics technique. The upper body was modeled as a four link open kinematic chain with seven degrees of freedom. The Resolved Motion Method used for the robot kinematics problem was used to predict the joint movements. The cost function of the perceived discomfort developed using the central composite design was also used as a performance function. This model predicts the posture by moving the joints to minimize the discomfort on the constraint of the end effector velocity directed to a target point. The results of the pairwise t-test showed that all the joint coordinates except the shoulder joint's showed statistically no differences at .alpha. = 0.01. The reach trajectory prediction model developed in this study was found to accurately simulate human arm reach trajectory and the model will help understand the human arm reach movement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 전기설비
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• pp.71-72
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• 2006

• 한국CDE학회논문집
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• 제18권5호
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• pp.359-366
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• 2013

In the lower arm design process, a tolerance optimization of the variance of design variables should be preceded before manufacturing process, since it is very cost-effective compared to a strict management of tolerance of products. In this study, a design of experiment (DOE) based on response surface model (RSM) was carried out to find optimized design variables of the lower arm, which can meet a given requirement of probability constraint for the process capability index (Cpk) of the weight and maximum stress. Then, the design space was explored by using the central composite design method, in which the 2nd order Taylor expansion was applied to predict a standard deviation of the responses. The optimal solutions satisfying the probability constraint of the Cpk were found by considering both of the mean value and the standard deviation of the design variables.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4163-4167
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• 2012

Aims: To prospectively assess the efficacy and safety of moderately hypofractionated conformal radiotherapy in patients with thoracic esophageal cancer. Methods and Materials: From Sept. 2002 to Oct, 2005, 150 eligible patients with T2-4N0-1M0 stage thoracic esophageal squamous cell cancers were enrolled to receive either conventional fractionated radiation (CFR) or moderately hypofractionated radiation (MHR) with a three-dimensional conformal radiation technique. Of the total, 74 received moderately hypofractionated radiation with total dose of 54-60Gy/18-20fractions for 3.5-4 weeks in the MHR arm, and 76 received conventional radiation with total dose of 60Gy/30 fractions for 6 weeks in the CFR arm. Concurrent chemotherapy comprised of paclitaxel and cisplatin. Safety was evaluated, and local control and overall survival rates were calculated. Results: Statistically significant differences between the CFR versus MHR arms were observed in local/regional failure rate (47.3% v 27.0%, P=0.034) and the percentage of patients with persistent local disease (26.3% v 10.8%, P=0.012). But 3 and 5-year overall survival rates (43.2%, 38.8% v 38.2%, 28.0%, respectively) were not different between the two arms (P=0.268). There were no significant differences in the incidences of grade 3 or higher acute toxicities (66.3% v 50.0%) and late complications rates (27.0% v 22.4%) between the MHR and CFR arms. Conclusions: Moderately hypofractionated, three-dimensional radiation treatment could improve the local control rate of esophageal cancer and potentially increase patients' survival.

• 대한한방부인과학회지
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• 제32권3호
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• pp.102-115
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• 2019

Objectives: The purpose of this study is to confirm the effectiveness and safety of acupuncture for treating breast cancer-related lymphedema (BCRL), thus providing a clinical basis for acupuncture treatment and helping to develop clinical practice guideline through consideration of used meridians and acupoints. Methods: Clinical studies applying acupuncture on breast cancer-related lymphedema were searched through 7 databases such as The Cochrane Library Central, Embase, Pubmed and CAJ. Interventions and results of the selected clinical studies were analyzed. Results: 8 Clinical studies were finally included according to inclusion and exclusion criteria. There were 6 randomized controlled studies and 2 single-arm pilot studies. All of those studies were searched in The Cochrane Library Central, Embase, Pubmed and CAJ and written in English and Chinese. Treatment group applied acupuncture as a Korean medicine intervention. Interventions of control group were made with non-treatment, upper limb exercise, and oral administration of capillary stabilizer or diuretics. Outcome measurements varied from paper to paper but every study measured reduction in arm circumference. Among 8 studies, 6 studies reported statistically significant reduction in arm circumference in treatment group and there were no serious adverse effects. Conclusions: This study suggested that acupuncture has few side effects as well as statistically significant effects on many aspects in treating breast cancer-related lymphedema. However the results should be taken cautiously as more clinical studies are needed.

• The Korean Journal of Pain
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• 제19권2호
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• pp.241-243
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• 2006

Central pain is defined as pain associated with lesions of the central nervous system, and is among the most intractable of chronic pain syndromes. A 47 year-old-female, who had right arm and shoulder pain, was diagnosed with syringomyelia of the Arnold Chiari malformation type I and received foramen magnum decompression and a syringo-subarachnoid shunt. After the operation, the evoked pain was improved, but she complained of a continuous burning pain, coupled with cold and tactile allodynia. This symptom failed to fully subside on administration of oral medicine; therefore, brachial plexus block was performed, which relieved her pain transiently. Through repeated trials, a gradual decrease in the pain intensity and frequency was found. However, the way in which brachial plexus block improves spinal central pain is not completely known.