• Annals of Clinical Neurophysiology
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• 제12권2호
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• pp.61-65
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• 2010

Background: Orthostatic hypotension (OH) refers to a fall in systolic blood pressure (BP) of 20 mmHg or more, or in diastolic BP of 10 mm Hg or more within 3 minutes of standing up. The head-up tilt test (HUT) is the most useful, but potentially invasive test for the diagnosis of OH. The purpose of this study was to identify the usefulness of spontaneous baroreflex sensitivity (sBRS). Methods: Ninety one patients with orthostatic intolerance, in whom the HUT data were available, were included in the study. Patients were classified into HUT-positive (group I) and HUT-negative (group II) group. Twenty five healthy volunteers served as normal controls, and were designated as group III. In all subjects, beat-to-beat BP and heart rate were recorded using BeatScope 1.1a. We collected the 50 sBRS data in each patient in a supine position. The average value of one to ten of 50 sBRS data was defined as sBRS10, one to twenty as sBRS20, one to thirty as sBRS 30, one to forty as sBRS 40, and one to fifty as sBRS 50. Differences in sBRS10 and sBRS50 levels were statistically analyzed and compared between groups I, II, and III. Results: No significant difference in the sBRS50 level was found between Groups II and III. sBRS50 was significantly lower in Group I than in Groups II and III (p<0.05), and the same pattern of differences was observed for sBRS40, sBRS30, sBRS20, and sBRS10. Conclusions: Patients with OH showed significantly lower sBRS levels than HUT-negative patients or normal controls. Our study implies that a supine-position sBRS would provide additional diagnostic information for OH.

• 한국방사선학회논문지
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• 제15권4호
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• pp.401-408
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• 2021

양성자 치료는 방사선치료 중 하나로 브래그 피크로 알려진 물리적 특성을 활용한 방법이다. 양성자 치료계획 수립 시 주로 전산화단층촬영(CT)의 인체 횡단면 영상이 사용되고 있다. CT는 사용되는 관전압에 따라 HU가 변하게 되며 이는 구조물의 경계, 두께 변화로 이어진다. 본 연구는 Geant4를 이용하여 복합 물질로 구성된 두개골 팬텀에서 두께 변화에 따른 뇌 영역의 브래그 곡선의 변화를 살펴보았다. 먼저, 단일 물질로 구성된 팬텀에서 매질의 종류와 양성자의 입사에너지에 따른 브래그 곡선을 측정하여 Geant4 계산결과의 신뢰성을 확보하였다. 두개골 팬텀의 각 두께를 변동하였을 때 뇌 영역에서 발생하는 피크의 위치변화를 측정하였다. 연부조직의 두께를 변화하였을 때 피크의 위치 변화는 나타나지 않았으며, 피부의 두께를 변화하였을 때 피크의 변화는 적었으며, 주로 뼈의 두께를 변화할 때 피크의 위치 변화가 나타났다. 또한 뼈를 단독으로 변화하였을 때와 뼈를 다른 조직과 함께 변화하였을 때 피크의 위치 변화량은 동일하였다. 뼈의 정확한 두께 측정이 방사선치료계획의 선량-깊이 분포 예측에 주요 인자 중 하나임을 확인하였다.

• 대한방사선치료학회지
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• 제26권1호
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• pp.99-105
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• 2014

목 적 : 본 연구에서는 두경부 암 환자의 방사선 치료 시 Neck node lower region까지 Target이 위치한 환자의 경우 기존의 상품화 된 두 가지 고정용구와 자체개발한 Shoulder Retractor의 유용성을 비교 평가하고자 한다. 대상 및 방법 : 본원에서 치료한 두경부암 환자 6명을 대상으로 사용한 고정용구의 종류에 따라 각각 2명씩 분류하여 좌, 우 Shoulder 위치변화와 Set up의 정확성을 OBI를 이용한 2D/2D 영상정합 위치보정 후 좌표 분석을 통해 비교하여 유용성을 확인해 보았다. 결 과 : 고정용구 종류에 따른 영상정합 위치보정 값(OBI A-P상 좌, 우 Shoulder 위치변화값)에 대한 평균값과 표준편차는 A그룹에서는 RT.Shoulder $1.07mm{\pm}3.99mm$, LT.Shoulder $-4.35mm{\pm}2.09mm$이고, B그룹에서는 RT.Shoulder $-0.37{\pm}5.91mm$, LT.Shoulder $1.26{\pm}5.28mm$, C그룹에서는 RT.Shoulder $-0.63{\pm}2.44mm$, LT.Shoulder $0.25mm{\pm}1.61mm$으로 나타났다. SET UP의 영상유도좌표 분석에서는 평균 및 표준편차 값이 A그룹에서 Vrt $-2.06{\pm}2.68mm$, Lat $-1.11{\pm}8.15mm$, Lng $0.34{\pm}3.78mm$, Rot $0.51{\pm}0.77^{\circ}$이고, B그룹에서 Vrt은 $-1.18{\pm}1.82mm$, Lat $-0.94{\pm}2.13mm$, Lng $-0.67{\pm}1.98mm$, Rot $0.91{\pm}1.04^{\circ}$이고, C그룹에서 Vrt은 $0.12{\pm}2.18mm$, Lat에서 $-0.79{\pm}1.62mm$, Lng에서 $-0.79{\pm}2.64mm$, Rot $0{\pm}0.49^{\circ}$으로 나타났다. 결 론 : 자체개발한 고정용구는 좌,우 Shoulder의 위치변화에 대한 재현성을 유지시킴에 있어 유용함을 알수있었고, 환자 변위요소(환자가 잡은 줄을 놓치는 현상과 발 끝의 위치와 모양에 따라 잡은줄이 한쪽으로 치우치는 현상)와 환자의 체중 변화로 인한 환자 자세의 고정문제를 줄임으로써 Set up의 오차를 줄이고 환자의 재현성을 유지시키는데 도움이 될 것으로 사료된다.

• 대한소아치과학회지
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• 제26권3호
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• pp.564-571
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• 1999

설골은 주위골 조직과는 직접적인 연결이 없이 근육과 인대를 통해 혀, 하악골, 두개골, 쇄골, 견갑골, 갑상연골, 인두 등에 연결된다. 이러한 특이한 해부학적 관계 때문에 설골의 위치는 하악의 위치, 머리의 위치, 기도상태에 따라 변하게 된다. 이에 저자는 설골과 부정교합과의 관계, 기도와의 연관성에 대해 알아보고자 경북대학교 소아치과에 부정교합을 주소로 내원한 환아 64명 (남자 : 39명, 여자 : 25명, I급 부정교합 : 25명, II급 부정교합 : 15명, III급 부정교합 : 24명)의 설골의 위치를 측면 두부방사선 규격사진상에서 계측하여 다음과 같은 결론을 얻었다. 1. I, II급 부정교합환아에 비해 III급 부정교합환아에서 설골은 더 전방에 위치하였고, 설골의 경사도도 더 완만하였다. 2. I, II, III급 부정교합환아에서 설골은 하악골과 척추골사이의 전후방적 위치는 일정하였다. 3. 설골은 하부기도의 전방경계를 이루는 골격구조임을 알 수 있었다.

• 대한치과교정학회지
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• 제47권5호
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• pp.277-288
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• 2017

Objective: Treating Class II subdivision malocclusion with asymmetry has been a challenge for orthodontists because of the complicated characteristics of asymmetry. This study aimed to explore the characteristics of dental and skeletal asymmetry in Class II subdivision malocclusion, and to assess the relationship between the condyle-glenoid fossa and first molar. Methods: Cone-beam computed tomographic images of 32 patients with Class II subdivision malocclusion were three-dimensionally reconstructed using the Mimics software. Forty-five anatomic landmarks on the reconstructed structures were selected and 27 linear and angular measurements were performed. Paired-samples t-tests were used to compare the average differences between the Class I and Class II sides; Pearson correlation coefficient (r) was used for analyzing the linear association. Results: The faciolingual crown angulation of the mandibular first molar (p < 0.05), sagittal position of the maxillary and mandibular first molars (p < 0.01), condylar head height (p < 0.01), condylar process height (p < 0.05), and angle of the posterior wall of the articular tubercle and coronal position of the glenoid fossa (p < 0.01) were significantly different between the two sides. The morphology and position of the condyle-glenoid fossa significantly correlated with the three-dimensional changes in the first molar. Conclusions: Asymmetry in the sagittal position of the maxillary and mandibular first molars between the two sides and significant lingual inclination of the mandibular first molar on the Class II side were the dental characteristics of Class II subdivision malocclusion. Condylar morphology and glenoid fossa position asymmetries were the major components of skeletal asymmetry and were well correlated with the three-dimensional position of the first molar.

• Journal of Oral Medicine and Pain
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• 제20권1호
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• pp.171-183
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• 1995

This study was carried out to investigate the relationship between tensed mandibular positions, muscle tenderness and EMG activity, respectively, and between range of motion of the neck and sternocleidomastoid muscle tenderness. Under stressful conditions, most of people take several types of behavioral patterns. Two of them observed frequently are clenching of teeth and grasping of fist. Prolonged clenching or grasping should increase electromyographic activity of associated muscle, especially muscles of mastication and neck muscles and will cause hyperfunction, dysfunction and muscle pain. So it is necessary to relate EMG activity with muscle pain. The author performed routine clinical examination in 47 patients with Temporomandibular Disorders, especially for presence or absence of muscle tenderness. Mandibular rest position was used as a baseline reference position and two more position in which EMG activity was taken were rest postion with grasping of fist and teeth clenching position. BioEMG of Biopak system (Bioresearch Inc, USA) was used for measuring of integrated EMG in masseter, anterior temporalis, anterior belly of digastic muscle and sternocleidomastoid muscle. To measure of the range of neck motion. CROM(Cervical-Range-of Motion, USA) was used. The obtained results were as follows : 1. EMG activity of all muscles except in masseter was higher in grasping of fist than those in rest position and there were significant correlation in EMG activity between the two position except in anterior belly of digastric muscle. 2. When comparing EMG activity between tender and non-tender muscle, all examined muscles did not show any significant difference. From this data, we could conclude that EMG activity was generally not changed with tenderness, of couse, it might be dependent with degree of muscle tenderness. 3. Number of tender points in examined muscles was also not significantly different between in patients with masticatory muscle disorders and in patients with internal derangement. 4. Cervical posture and range of motion of the neck was not differed significantly between in patients with and in patients without tenderness of sternocleidomastoid muscle.

• 한국기계가공학회지
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• 제17권6호
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• pp.136-143
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• 2018

Recently, with the rapid development of virtual reality technology, there have been more and more applications of virtual reality technology in various fields. In order to realize a virtual reality, a method of implementing a visualization environment through an HMD (Head Mounted Display) is widely used. However, in the current visualization environment through the HMD, the user feels dizziness when worn, It has the disadvantage of imposing restrictions on. In this study, it is aimed to realize virtual reality visualization environment through multi-screen environment which improves the experience effect of virtual environment by using existing screen instead of visualization through HMD, and compensates for shortcomings of HMD method. In order to realize a multi-screen environment as a highly visualized environment, a technique for matching the spatial position of the multi-screen with the spatial position of the virtual environment is required. To do this, we need an efficient method to precisely measure the position of the space, and we propose a spatial position compensation methodology that can efficiently and precisely measure the position of the real space and reflect it in the virtual environment.

• PNF and Movement
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• 제18권3호
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• pp.403-414
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• 2020

Purpose: This study examined how performing chin tuck exercises in supine, sitting, and standing positions affects changes in the muscle activity of the neck and shoulder. Methods: Seventeen men and three women with forward head posture participated in the study. The subjects performed the chin tuck exercise using a pressure biofeedback unit. After determining the ideal order for performing the chin tuck exercise in supine, sitting, and standing positions through randomized controlled trials, muscle activity was measured in the dominant-side sternocleidomastoid, scalenus anterior, upper trapezius, and levator scapulae. Muscle activity was measured three times in each muscle for each position, and the average of the three measurements was used for analysis. Results: In this study, the chin tuck exercise performed in a supine position reduced muscle activity of the sternocleidomastoid, scalenus anterior, upper trapezius, and levator scapulae significantly more than performing the exercise in either sitting or standing positions (p < 0.05). No significant difference in muscle activity was observed when the exercise was performed in a sitting position versus a standing position (p < 0.05). Conclusion: Performing a chin tuck exercise in a supine position is more effective for stabilizing the neck and shoulder than performing it in a sitting or standing position, as it reduces excessive tension and fatigue in the neck and shoulder.

• 한국항해학회지
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• 제11권2호
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• pp.33-52
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• 1987

The disasters of wet bound vessels have been more frequent than those of east bound ones on the sea routes of the North Pacific Ocean in winter season. M/V Hanjin-Inchon was also west bound in her missing voyage. The container vessel of 17, 676 gross tons, M/V Hanjin-Inchon owned by Hanjin Shipping Co.Ltd in Seoul Korea left seattle in west coast of U.S.A for Pusan , Korea on the 5th Feb., 1987 and sailed along the exact courses recommended by Ocean Routes until she reported her position and speed as 49-30N, 158-00E and 8 knots to her head office in Seoul by this ship's time 2200 hours on the 13th Feb., 1987. The above message turned out to be last message from her because she had been missing since then leaving no message but only two life boats of her name, three containers cases, large scale of oil slicks and the corpse of her 3rd mate drifting on the sea near the position reported by her last message.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.277-280
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• 1998

The paper provides an overview of those requirements. A detailed description is given of the construction of the new channel code, called 24/25 code, that compiles with the given constraints and involves only a minor drawback in terms of the overhead needs. The servo position information is recorded as low frequency componets, pilot tracking tones, which are embedded in the recorded stream of binary digits. Pilot tracking Tones are used to derive head position reference information in camcorders and DVCRs. A simple pilot tone encoder has been designed by using a new approach, "2 path precoder". Owing to this method, the hardware size can be significantly reduced. the correctness of the method has been verified by theoretical analysis and by extensive simulation.imulation.