• 디지털산업정보학회논문지
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• 제8권3호
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• pp.97-124
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• 2012

This paper analyzes qualitatively the stereo 3D content factors causing viewer's discomfort. For this, we perform a subjective test that each subject strokes a specific key whenever he (she) feels discomfort during watching a stereo 3D contents. Also we extract the data for the factors in the 3D contents to obtain their quantitative values and the amounts of the temporal changes. Those two sets of data are used to analyze the contents to find the factors which cause viewer's discomfort. The factors to be considered are the amount and the frequency of the disparity changes, story of the contents, situation or environments of a scene, movement and the position of the camera, color and luminance information as well as disparities themselves. We analyse the various strong and weak factors and their composites to find how much discomfort each factor or composite causes. We also show the situations and their related factors that causes less discomfort than the amount of their disparities.

• 전자공학회논문지SC
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• 제40권3호
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• pp.189-198
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• 2003

영상 안진기(VOG, Videooculograph)는 전정 안반사의 객관적 평가 방법으로 이용되고 있는 안구 운동 측정 방법 중의 하나이다. 영상 안진기의 핵심 기술은 눈꺼풀이나 속눈셉, 각막 반사, 그리고 눈 깜박임과 같은 영향에 덜 민감하면서 동공의 중점과 회전 운동을 정확하게 찾는 것이다. 회전 운동의 측정에 있어 부정확한 동공의 중점은 부정확한 회전 운동 측정으로 이어지므로 3차원 영상 안진기에서는 중점의 정확한 추정이 매우 중요하다. 이를 위해 잡음에 영향을 적게 받는 동공 중점을 찾는 새로운 알고리즘을 제안하고 알고리즘의 성능에 영향을 주는 인자에 대해 분석하여 최적의 조건을 찾았다. 그리고 제안한 방법을 이용하여 안구의 수평, 수직, 회전 운동, 그리고 동공의 크기 변화를 측정할 수 있는 실시간 3차원 VOG 시스템을 구현하였다.

• 대한치과교정학회지
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• 제24권3호
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• pp.649-658
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• 1994

The purpose of this study was to evaluate the association between incisor root resolution and sex, age, extraction, the magnitude and direction of tooth movement. The sample consisted of 189 randomly selected orthodontic patients, receiving standard edgewise orthodontic treatment in three private orthodontic onces at San Francisco. Pre-treatment and post-treatment periapicals and cephalometric radiographs were digitized. Measurements and superimpositions were made utilizing a computerized cephalometric analysis program. The variables were statistically analyzed. The results were as follows: 1. Mean apical root resorption values were $0.77{\pm}2.08mm$ for upper right central incisor, $0.88{\pm}2.11mm$ for upper left central incisor, $-0.05{\pm}2.09mm$ for lower right central incisor and $0.11{\pm}1.85mm$ for lower left central incisor. Apical root resorption of upper incisor was greater than lowers. 2. No correlation was found between sex and apical root resorption. 3. Apical root resorptions in adolescents were smaller than those in adults. 4. Apical root resorption was not affected by extraction. 5. Apical root resorption values of upper incisor were correlated to the horizontal and vertical movement of apex; Apical root resorption values of lower incisor were correlated to the vertical movement of apex.

• 대한기계학회논문집A
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• 제24권4호
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• pp.907-915
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• 2000

The movement of teeth and initial stress associated with the treatment of orthodontics have been successfully studied using the finite element method. To reduce the effort in preprocessing of finite element analysis, we developed two types of three-dimensional finite element models based on the standard teeth model. Individual malocclusions were incorporated in the finite element The movement of teeth and initial stress associated with the treatment of orthodontics have been successfully studied using the finite element method. To reduce the effort in preprocessing of finite element analysis, we developed two types of three-dimensional finite element models based on the standard teeth model. Individual malocclusions were incorporated in the finite element models by considering the measuring factors such as angulation, crown inclination, rotation and translations. The finite element analysis for the wire activation with a T-loop arch wire was carried out. Mechanical behavior on the movement and the initial stress for the malocclusion finite element model was shown to agree with the objectives of the actual treatment. Finite element models and procedures of analysis developed in this study would be suitably utilized for the design of initial shape of the wire and determination of activation displacements.

• 디자인학연구
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• 제17권2호
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• pp.23-32
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• 2004

본 연구는 사용자의 시지각 프로세스에 대한 분석을 통해 시선추적 과정을 이해하고, 인간의 정보처리 모델을 기반으로 휴리스틱 가이드라인을 도출하여, 실무에서 적용할 수 있는 인터페이스 디자인의 일반적인 원리를 발견하는 것에 목적이 있다. 이를 위해 인간의 시각 특성을 이용한 시선추적 시스템을 실험에 적용하여, 상향처리와 하향처리의 시지각 프로세스를 파악하고 인간의 정보처리 모델을 근거로 디자인을 위한 적용점을 분석하였다. 사례 연구로 인터랙티브 미디어를 실험하여 시선의 동선 및 고정점을 통해 사용자의 관심을 확인하고, 사용자의 인지과정을 이해하기 위한 단서를 효과적으로 얻을 수 있었다 그리고, 인간 행위의 각 단계와 정보처리 모델을 기반으로 다섯 가지의 휴리스틱 가이드라인을 도출하였으며, 이를 통하여 디자인 실무에서 직접 적용할 수 있는 인터페이스 디자인의 일반적인 원칙을 발견할 수 있었다.

• The Journal of Korean Physical Therapy
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• 제28권5호
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• pp.303-307
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• 2016

Purpose: This study was conducted to determine the effects of Mulligan's mobilization with movement (MWM) on changes in the talofibular interval in the sagittal plane in subjects with chronic ankle instability (CAI). Methods: Sixteen subjects with chronic ankle instability participated in this study. The talofibular intervals were measured from US images, and the weight-bearing lunge test was used to assess dorsiflexion of the ankle joint. Each dependent variable were measured on the both affected side and sound side in three trials in pre- and post-MWM. Dependent variables were examined with a two-way mixed-design analysis of variance (ANOVA). The two factors were side (sound side versus affected side) and intervention (pre- versus post-intervention). For post hoc analysis, paired t-tests were performed to compare the dependent variables. A p<0.05 was considered to indicate significance. Results: Dorsiflexion and talofibular interval differed significantly pre- and post-intervention (p<0.05). Post-hoc analysis revealed that the talofibular interval post-MWM was significantly less than that pre-MWM on the both the affected and sound side (p<0.05). The ankle dorsiflexion in the post-MWM group was significantly greater than that in the pre-MWM group on the affected side and the sound side (p<0.05). Conclusion: The Mulligan's MWM decreased the talofibular interval in subjects with CAI. These findings suggest that the MWM technique can change the position of the talus relative to the fibular in the weight bearing position.

• 한국운동역학회지
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• 제21권2호
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• pp.181-187
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• 2011

The purpose of this study was to identify major factors on pirouette in ballet, and especially angle, Center of Mass(CM) & muscle activity aspects. The data were collected by using Motion Analysis System with 12 cameras to analyze kinematic variables with 120 Hz and Electromyography(EMG; 4,000 Hz) & Force Platform(1,000 Hz) to analyze kinetic variables. The subjects of this study were 8 female ballet dancers. The results as follow. First of all, full extension of knee joint and full plantar flexion of ankle joint appeared at the similar point. Secondly, in the rotational phase, total movement of segments in Good motion is smaller than that of Bad motion(in Good motion, head movement 2.70 cm, right shoulder movement 0.72 cm, left shoulder 4.26 cm, left wrist 17.4 mm smaller than Bad motion). Third, CoP distance of Good motion is 11.76 mm, and CoP distance of Bad motion is 11.76 mm, so Good motion is 5.98 mm smaller). Lastly, Pirouette need more retus femur activity than gastrocnemius activity in extention phase and rotation phase of support leg.

• 한국산림과학회지
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• 제37권1호
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• pp.31-34
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• 1978

은수원사시나무 1/1년생(年生), 1/2년생(年生) 및 7/8년생(年生)에 대(對)하여 간(幹)의 수액류속도(樹液流速度)을 관찰(觀察)하였던 바 유속(流速)은 수령간(樹令間)과 포지(圃地)의 토양수분(土壤水分)의 차이(借異)보다는 공중습도(空中濕度)와 착엽성(着葉性)에 가장 크게 영향을 받고 다음은 기온(氣溫)에 영향받고 있음을 볼 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제3권3호
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• pp.266-284
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• 2009

The challenges of rapidly growing numbers of mobile nodes in IPv6-based networks are being faced by mobile computing researchers worldwide. Recently, IETF has standardized Mobile IPv6 and Fast Handover for Mobile IPv6(FMIPv6) for supporting IPv6 mobility. Even though existing literatures have asserted that FMIPv6 generally improves MIPv6 in terms of handover speed, they did not carefully consider the details of the whole handover procedures. Therefore, in conventional protocols, the handover process reveals numerous problems manifested by a time-consuming network layer based movement detection and latency in configuring a new care of address with confirmation. In this article, we study the impact of the address configuration and confirmation procedure on the IP handover latency. To mitigate such effects, we propose a new scheme which can reduce the latency taken by the movement detection, address configuration and confirmation from the whole handover latency. Furthermore, a mathematical analysis is provided to show the benefits of our scheme. In the analysis, various parameters are used to compare our scheme with the current procedures, while our approach is focused on the reduction of handover latency. Finally, we demonstrate total handover scenarios for the proposed techniques and discussed the major factors which contribute to the handover latency.

• Fibers and Polymers
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• 제6권1호
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• pp.89-94
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• 2005

The purpose of this study is to offer acoustical database of warp knitted fabrics by investigating frictional sound properties and physiological responses according to structural parameters such as construction, lap form, and direction of mutual guide bar movement. Fabric sounds of seven warp knitted fabrics are recorded, and Zwicker's psychoacoustic param­eters - loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z) - are calculated. Also, physiological responses evoked by frictional sounds of warp knitted fabrics are measured such as electroencephalogram (EEG), the ratio of high fre­quency to low frequency (HF/LF), respiration rate (RESP), skin conductance level (SCL), and photoplethysmograph (PPG). In case of constructions, frictional sound of sharkskin having higher loudness(Z) and fluctuation strength(Z) increases RESP. By lap form, open lap has louder and larger fluctuating sound than closed lap, but there aren't significant difference of physi­ological responses between open lap and closed lap. In direction of mutual guide bar movement, parallel direction evokes bigger changes of beta wave than counter direction because of its loud, rough, and fluctuating sound. Fluctuation strength(Z) and roughness(Z) are defined as important factors for predicting physiological responses in construction and mutual guide bar movement, respectively.