Background: Thoracic spine self-mobilization exercise is commonly used to manage patients with neck pain. However, no previous studies have investigated the effects of thoracic spine self-mobilization exercise alone in patients with chronic neck pain. Objects: The purpose of this study was to investigate the effects of thoracic self-mobilization using a tool on cervical range of motion (ROM), disability level, upper body posture, pain and fear-avoidance beliefs questionnaire (FABQ) in patients with chronic neck pain. Methods: The subjects were 49 patients (21 males, 28 females) with chronic neck pain. The subjects were randomly divided into an experimental group (EG, n = 23) and control group (CG, n = 26). For the EG, thoracic self-mobilization was applied. We placed a tool (made with 2 tennis balls) under 3 different vertebral levels (T1-4, T5-8, T9-12) of the thoracic spine and the subjects performed crunches, which included thoracic flexion and extension in supine position. Five times × 3 sets for each levels, twice a week, for 4 weeks. Cervical pain, disability, upper body posture, FABQ results, and ROM were evaluated at baseline, after 4 weeks of intervention, and at 8 weeks of follow-up. Assessments included the quadruple visual analogue scale (QVAS); Northwick Park neck pain questionnaire (NPQ); craniovertebral angles (CVA), forward shoulder angle (FSA) and kyphosis angle (KA) measurements for upper body posture; FABQ and cervical ROM testing. Results: The EG showed a statistically significant improvement after intervention in the QVAS (–51.16%); NPQ (–53.46%); flexion (20.95%), extension (25.32%), left rotation (14.04%), and right rotation (25.32%) in the ROM of the cervical joint; KA (–7.14%); CVA (9.82%); and FSA (–4.12%). Conclusion: These results suggest that, for patients with chronic neck pain, thoracic selfmobilization exercise using a tool (tennis balls) is effective to improve neck pain, disability level, the ROM, and upper body posture.

The stochastic point-source model has been widely used in generating artificial ground motions, which can be used to develop a ground motion prediction equation and to evaluate the seismic risk of structures. This model mainly consists of three different functions representing source, path, and site effects. The path effect is used to emulate decay in ground motion in accordance with distance from the source. In the stochastic point-source model, the path attenuation effect is taken into account by using the geometrical attenuation effect and the inelastic attenuation effect. The aim of this study is to develop accurate equations of ground motion attenuation in the Korean peninsula. In this study, attenuation was estimated and validated by using a stochastic point source model and observed ground motion recordings for the Korean peninsula.

Background: Shoulder function is achieved by the coordinated movements of the scapula, humerus, and thoracic spine, and shoulder disorders can be associated with altered scapular kinematics. The trunk plays an important role as the kinematic chain during arm elevation. Objects: The purpose of this study was to determine the effects of thoracic hyperkyphosis on scapular orientation and trunk motion. Methods: Thirty-one subjects (15 in the ideal thorax group and 16 in the thoracic hyperkyphosis group) performed right-arm abduction and adduction movements in an unconstrained plane. The scapular orientation and trunk motion were recorded using a motion analysis system. Results: Those subjects with thoracic hyperkyphosis displayed greater scapular posterior tilting at a 120˚ shoulder elevation, greater scapular internal rotation throughout the arm raising phase, and greater trunk axial rotation at the upper ranges of the shoulder elevation, compared to those subjects with an ideal thorax (p<.05). Conclusion: Thoracic hyperkyphosis can cause scapular instability, greater trunk rotation and greater scapular posterior tilting, and may contribute to preventing the achievement of a full range of humeral abductions in an unconstrained plane.

Background: In patients with lumbar spinal stenosis (LSS), lumbar flexion exercise (LFE) is considered a standard therapeutic exercise that widens the space between the spinal canal and intervertebral foramen. However, some researchers have reported that lumbar extension exercise (LEE) may improve lumbar pain and functional ability in patients with LSS. Although exercise intervention methods for patients with LSS have been widely applied in clinical settings, few studies have conducted comparative analysis of these exercise methods. Objects: This study aimed to compare the effects of LFE, LEE, and lumbar flexion combined with lumbar flexion-extension exercise (LFEE) on pain, range of motion (ROM), pelvic tilt angle, and functional gait ability in patients with LSS. Methods: A total of 30 patients with LSS, LFE (n1=10), LEE (n2=10), and LFEE (n3=10) were assigned to each of the three exercise groups. The numerical pain rating scale (NPRS), modified-modified schober test (MMST)-flexion, MMST-extension, pelvic tilt inclinometer, and 6-minute walking test (6MWT) were measured. Results: After the intervention, statistically significant differences were observed in the NPRS (p=.043), MMST-flexion (p<.001), MMST-extension (p<.001), and 6MWT (p=.005) between groups. According to the post hoc test, the NPRS was statistically significant difference between the LFEE and LEE groups (p=.034). The MMST-flexion was statistically significantly different between the LFE and LEE (p=.000), LFE and LFEE (p=.001), and LEE and LFEE (p=.001) groups. The MMST-extension was statistically significantly different between the LFE and LEE (p<.001), LFE and LFEE (p=.002), and LEE and LFEE (p=.008) groups. The 6MWT was statistically significantly different between the LFE and LFEE (p=.042) and the LEE and LFEE (p=.004) groups. Conclusion: This study suggested that LFEE was the most effective exercise for pain and functional gait ability in patients with LSS, LFE was the most effective exercise for lumbar flexion ROM, and LEE was the most effective exercise for lumbar extension ROM.

Background: Ipsilateral pelvic elevation has been reported as a common compensatory movement during side-lying hip abduction. It has been reported that pelvic elevation inhibits sufficient contraction of gluteus medius. However, few studies have identified the effects of controlled pelvic elevation on the trunk and hip muscles. Objective: To examine the effects of controlled pelvic elevation using visual biofeedback on the muscle activity of the trunk and hip muscles. Design: Crossover study. Methods: Twelve healthy males performed side-lying hip abduction exercises with and without visual biofeedback for pelvic elevation. Electromyography (EMG) activities of the gluteus medius, quadratus lumborum, and multifidus were analyzed using a wireless EMG system while the ipsilateral pelvic elevation angle was measured using a motion sensor during side-lying hip abduction exercises. Results: EMG activities of the gluteus medius (p = .002), quadratus lumborum (p = .022), and multifidus (p = .020) were significantly increased and ipsilateral pelvic elevation was significantly decreased (p = .001) during side-lying hip abduction with visual biofeedback compared to without visual biofeedback. Conclusions: The results of this study suggest that the application of biofeedback for pelvic motion could improve the trunk and hip muscle activation pattern and decrease compensatory pelvic motion during side-lying hip abduction exercise.

Background: Although magnetic resonance imaging is accurate, it is expensive to measure the movement of temporomandibular joint. The three-dimensional (3D) motion analysis system is an inexpensive measurement tool. Objects: This study examined the reliability of quantifying the mouth opening and lateral mandibular shift and differences between individuals with and without temporomandibular disorder (TMD) using the hygienic method of surface markers on the skin with 3D ultrasound-based motion analysis. Methods: This study included 24 subjects (12 with and 12 without TMD). Temporomandibular joint motion during mouth opening was recorded using two surface markers with 3D ultrasound-based motion analysis. An intraclass correlation coefficient [ICC (3,k)] was used to confirm the intrarater reliability of quantifying kinematic temporomandibular joint motion, and an independent t-test was used to evaluate differences in maximal mouth opening and lateral mandibular shift between the two groups. Results: Assessment of mouth opening and lateral mandibular shift showed excellent test–retest reliability with low standard error of measurement. The lateral mandibular shift and opening-lateral mandibular shift ratio were significantly increased in the TMD group during maximum mouth opening (p<.05). However, no significant difference in maximal mouth opening was observed between the groups with and without TMD (p>.05). Conclusion: This hygienic and simple surface marker method can be used to quantify the mouth opening and lateral mandibular shift at the end-range of mouth opening. The TMD group showed an increased lateral mandibular shift movement at the end-range of mouth opening. The lateral mandibular shift movement can be regarded as a symptom in the diagnosis and treatment of TMD.

Background: The hyoid bone is the only non-jointed structure among the skeletal tissues of the head and neck region, and its movement and posture depend on the attached muscle, ligament, and fascia. The location of the hyoid bone is important for airway maintenance, vocalization, chewing, swallowing, breathing, and head and scapular position. In general, the location of the hyoid bone is measured using radiographs and 3D computed tomography, and no studies have reported on clinical measurement methods. Objects: This study was performed to suggest clinical measurement methods for lateral deviation of the hyoid bone and to evaluate their reliability. Methods: In this study, 24 healthy volunteers (12 males, 12 females) in Cheongju-si participated. Two examiners performed the center point test and lateral motion test twice each to measure the lateral displacement of the hyoid bone. The reliability of the center point test was analyzed using intra-class correlation coefficients (ICC), and the reliability of the lateral motion test was analyzed using Cohen’s kappa coefficient. Results: The intra-rater reliability of the center point test was good, and the inter-rater reliability was moderate. The intra- and inter-rater reliability of the lateral motion test showed substantial reliability. Conclusion: Based on these results, the center point test and the lateral motion test can be used as an alternative methods of the measurement of lateral deviation of the hyoid bone for people who have musculoskeletal disorders of the head, neck, and scapula.

Background: Measurement of passive ankle dorsiflexion range of motion (ADROM) is often part of a physical therapy assessment. Objects: The objective of this study was to identify the effects of subtalar joint neutral position (SJNP) on passive ADROM according to knee position in young adults. Methods: We recruited 14 young adult participants for this study. Two examiners used a universal goniometer to measure passive ADROM with and without SJNP. Dorsiflexion force was applied to the forefoot until maximum resistance was reached in two knee positions (extension and 90˚ flexion) in the prone position. Subtalar joint position was also recorded at maximum ADROM. Passive ADROM was measured three times at different knee and subtalar joint positions, in random order. Two-way repeated-measures analysis of variance was used to compare the effects of subtalar joint and knee position on passive ADROM. Results: Passive ADROM was significantly lower with than without SJNP during both knee extension (mean difference: 7.4˚) and 90˚ flexion (mean difference: 16.9˚) (p<.01). Passive ADROM was significantly higher during 90˚ knee flexion than during knee extension both with (mean difference: 5.8˚) and without SJNP (mean difference: 15.2˚) (p<.01). The valgus position of the subtalar joint was significantly lower with than without SJNP during both knee extension (mean difference: 3.3˚) and 90˚ flexion (mean difference: 4.3˚) (p<.01). Conclusion: Our results indicate that the gastrocnemius may limit ankle dorsiflexion more than the soleus does. Greater dorsiflexion at the subtalar and midtarsal joints was observed during passive ADROM measurement without than that with SJNP; therefore, SJNP should be maintained for accurate measurement of ADROM.

Background: Sling exercises are frequently used for the rehabilitation process of patients with shoulder joint injuries, but research on the significant frequency intensity and appropriate treatment duration for sling exercises with local vibration stimulation is lacking. Objects: The aim of this study was to investigate the effects of sling exercise with vibration on shoulder range of motion (ROM), muscle strength, pain, and dysfunction in patients with a medical diagnosis of shoulder joint injury. Methods: Twenty-two patients were randomly assigned to the experiment and control groups. Six sling exercises with and without 50 ㎐ vibrations were applied in the experiment and control groups, respectively. Each exercise consisted of 3 sets of 5 repetitions performed for 6 weeks. The assessment tools used included shoulder joint range of motion, muscle strength, pain level, and shoulder pain and disability index for functional disability. We conducted re-evaluations before and 3 and 6 weeks after intervention. The changes in the measurement variables were analyzed and compared between the two groups. Results: The ROM of the external rotation of the shoulder joint had a significant interaction between the group and the measurement point (F=3.652, p<.05). In both groups, we found a significant increase in external rotation angle between the measurement points (p<.05). The flexor strength of the shoulder joint significant interaction between the group and the measurement point (F=4.247, p<.05). Both the experiment (p<.01) and control groups (p<.05) showed a significant increase in shoulder flexor strength at the measurement points. After 6 weeks of the interventions, both the groups showed significantly improved VAS (p<.01), SPADI (p<.01), and orthopedic tests (p<.01). However, there was no significant difference between the group and the measurement point in terms of the clinical outcomes observed. Conclusion: The sling exercise with local vibration of 50 ㎐ affected the external rotation of the shoulder range of motion and improved shoulder flexor strength in the patients with shoulder injuries. Therefore, we propose the use of the sling exercise intervention with vibration in the exercise rehabilitation of patients with shoulder joint injuries.

The authors has predicted the maneuvering characteristics of a fishing vessel in deep water using Kijima's empirical formula in a previous study. Since the Kijima’s empirical formula was developed by a regression analysis of merchant vessels which have dimensions ( ,   , etc.) that are different from those of fishing vessels, it was possible to make a prediction approximately even with inaccurate estimation. In this study, the authors estimated the turning-motion characteristics of a model ship of fisheries training ship in shallow water based on the results of its previous study. The turning-motion characteristics of the model ship in shallow water was found out through quantitative analysis according to the water depth to ship draft ratio . In conclusion, the turning-motion characteristics of the model ship had significant changes immediately after an  , and this result will be helpful for sailing in shallow water.

자기 주도적으로 자신에게 맞는 자료와 정보통신 기술을 활용하는 학습유도 정책인 스마트교육은 현재 한국 교육의 중요한 목표중 하나이다. 스마트교육에 적합한 과학교육을 위한 스마트 콘텐츠의 주요 고려사항은 사용자의 수준과 적성을 고려한 자기 주도적이고 흥미로운 콘텐츠를 만드는 것이다. 특히 실험을 통하여 이론을 배우는 과학교육의 특성상 사용자 스스로 실험을 할 수 있는 내용이 포함되어야 한다. 본 연구는 초중등 과학 교과 과정의 교육목표를 충족시키는 실험을 통하여 이론을 학습할 수 있는 스마트교육 콘텐츠 개발에 대한 것이다. 초, 중등 과학 교과과정 중 물리의 기본이 되는 뉴턴의 운동법칙을 연구 대상으로 선정하였다. 전통적인 과학실에서 교사 한명이 다수의 학생을 상대로 교육하는 과학 실험이 가진 시간, 장소, 경제적 제한 그리고 실험시 안전사고의 가능성과 같은 단점들을 보완하고, 모든 사용자에게 평등한 배움의 기회를 가지도록 하는 것을 목표로 하였다. 본 연구에서 개발한 정규 교과과정을 충족하는 시리어스게임 형태의 뉴턴의 운동법칙 실험 콘텐츠를 통해 스마트교육시대의 교육 현장에서, 새로운 방식의 실험 콘텐츠의 가능성을 보여줄 수 있을 것이다.

This study performed a numerical analysis of a 3D unsteady viscous flow in order to investigate ship motion responses running through regular waves of the platform supply vessel. The feasibility of numerical analysis was tested under the three regular wave conditions of the KRISO container ship (KCS) suggested at the 2010 Gothenburg CFD Workshop. The resulting resistance coefficient, heave motion, and pitch angle were compared with the model test of the harmonic analysis. Also, the ship motion response characteristics of the platform supply vessel were performed using the proven method of the KRISO container ship (KCS). The ship motions including the resistance coefficient, heave motion, and pitch angle according to the time series were investigated via harmonic analysis under regular waves condition of λ/LPP=1.87 and HS=0.078m

In this study, a ship motion control system design method is introduced for autonomous ships. Some related research results and technologies for autonomous ships have already been developed and applied to testing ships. Recently, the Norwegian Maritime Authority and the Coastal Administration have signed an agreement and started to test autonomous ships in the defined area. Considering recent technology trends and background, in this paper, the authors also try to develop autonomous ship control technologies. In the designed control system, an observer is introduced to estimate unmeasurable system states. Based on the servosystem with state estimator, ship motion control experiment is performed to evaluate control performance using a model ship in water basin.

Background: There have been many studies on self-myofascial release (SMR) stretching, but there are few comparative studies on the effects of massages using a release ball, which is a type of the SMR method. Objective: To investigate the immediate effects of release ball massage and self- stretching on proprioceptive sensory, hamstring’s temperature, range of motion (ROM) muscle strength,. Design: Crossover study. Methods: Thirty women in 20’s at S University in Busan voluntarily participated in the study. Participants were random to release ball group (n=15) or selfstretching group (n=15). Both groups performed 3 sets of exercises, stretching for 30 seconds and resting for 15 seconds in each position. The proprioceptive sensory, temperature of the hamstring muscle, ROM, and strength were measured before exercise, 5 minutes after exercise, and 30 minutes after exercise. Results: Release ball group showed significant differences in muscle length and temperature over time (p<.05). The comparison between two group over time showed significant differences in muscle length, temperature, and muscle strength (p<.05). Conclusions: These results demonstrate that release ball massage and selfstretching are beneficial for improving hamstring's temperature, ROM and muscle strength.

가상현실이란 디지털로 표현된 가상 환경을 뜻하며 인터넷 쇼핑, 아바타 등 기본적으로 디지털 환경을 일컫는 단어이며, 최근에는 머리에 장착하는 디스플레이(HMD : Head Mounted Display)의 등장으로 사용자가 현실과 유사한 환경을 직접 경험하는 체험형 콘텐츠로서 의미를 확장했다. 현재 가상현실은 게임을 비롯한 힐링 콘텐츠, 관광, 군사 시뮬레이션 다양한 분야에서 주목받고 있으며 HMD의 보급 또한 활발하다. 사용자가 가상현실 콘텐츠를 체험하기 위해서는 몇 가지 제약이 발생하는데, 사용자의 시야가 차단되 현실공간감각이 상실된다. 따라서 기존에 사용되었던 입력장치인 키보드, 마우스 등의 사용에 어려움이 있으며 HMD를 개발하는 개발사들은 위의 문제를 해결하고자 가상현실 체험에 특화된 핸드트래킹 디바이스를 제공한다. 하지만 이 또한 상호작용, 이동, 제스처가 손에 집중되어있어 가상환경에 익숙하지 않은 이용자의 사용자 편의가 낮다. 본 논문은 이러한 이동의 문제를 아두이노를 통해 제작한 발 트레킹 디바이스로 이동을 분리시켜 해결하고자 하였다. IMU의 각속도계와 가속도계를 이용해 다리의 궤적을 측정하려 하였고, 이때 발생한 오차는 상보필터를 통해 해결하였다. 또한 기본적으로 발생하는 센싱-통신-연산 과정에서의 노이즈는 두가지 이동평균기법과 생략평균값을 이용해 안정화 시켰다. 사용자는 해당 장비와 Oculus Rift를 착용하고 Unity3d환경으로 구축된 실험환경에서 임무 수행 속도, 이동방향 오차율등을 측정해 기존 HMD컨트롤러와 본 논문에서 제시하는 컨트롤러를 비교 검증했다. 실험 결과 임무 수행 속도와 이동 오차율 모두에서 본 논문에서 제시하는 장치가 우수한 데이터를 제공하였다. 본 실험 결과를 토대로 이동조작 분리가 높은 접근성을 제공한다는 것을 확인하였다. 본 논문은 HMD 이동 컨트롤러를 포함한 이후 개발되는 다양한 사용자 제스처 인식 컨트롤러에도 적용 가능할것으로 보인다.

This study explores how Korean English learners process English caused-motion constructions (CMC) through online and offline experiments. The focus was on how Korean learners’ processing of English CMC is affected by the typological difference between English and Korean. Of the 77 volunteer participants recruited, 17 were native English speakers and 60 were Korean EFL learners. The experiments included a sentence completion task (SCT) as an online experiment, and an acceptability jugment task (AJT) and a translation (correction) task as offline experiments. The results showed that in the SCT, the Korean learners showed difficulty in combining process and result events with intransitive manner verbs. In the AJT, they rarely accepted the CMCs with intransitive manner verbs, but easily accepted the ‘causative verb + byphrase’ structures with the same type of verbs. When the sentences were employed in the AJT were asked to be translated into Korean, the low-intermediate Korean learners were likely to drop the result meaning and interpret the preposition phrase as a locative rather than a goal. In sum, Korean learners showed similar patterns to native English speakers in processing path verbs and transitive manner verbs, but different pattern in processing intransitive manner verbs. These findings demonstrate that Korean learners' processing of English CMC is heavily influenced by their L1 when the construction accompanied intransitive manner verbs.