• International journal of advanced smart convergence
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• 제4권2호
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• pp.163-169
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• 2015

This study proposes a sports simulation device with various harmonics generation. The proposed system is composed of 6 degrees of freedom simulator devices and three types of sports simulation such as walking, snowboard, and jet-ski. In this research, every joint movement is designed with a crank-and-slider mechanism, which is efficient for generating continuous curvature smoothly. Contrary to the conventional spatial simulator with linear actuators, harmonics generation and its spatial combinations become the crucial issue in this research. The harmonic pattern in each joint is modelled for generating smooth curvatures that are also superposed for achieving overall motions. In addition, the targeted motions of sports simulations have different physical factors of periodic gait motion, frictionless surface, and buoyant effects, which are respectively designed by integrating three dimensional graphics information.

• The Korean Journal of Physiology
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• 제11권2호
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• pp.73-78
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• 1977

In urethane anaesthetized rabbits, reflex contraction of the inferior oblique muscle of a unilateral rye was evoked by the stimulation of a relevant vestibular canal nerve. Eye movement evoked by the inferior oblique muscle contracion was carefully observed with naked eyes, and recorded by means of the electrooculographic and electronystagmographic methods. The following results were obtained. 1) Contraction of the inferior oblique muscle evoked by a canal nerve excitation produced excycloduction of the eyeball associated with depression (downward rotation) instead of elevation. 2) Such depression of the eyeball was demonstrated even after the resection of the inferior oblique muscle. These experimental evidences indicate that tile rotatory action (secondary action of the muscle) of the inferior oblique muscle in the rabbits is apparently different in its direction from those already reported in the binocular animals such as cat, dog and monkey.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 추계학술대회 논문집
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• pp.111-114
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• 1999

Off-vertical axis rotator was developed to differentiate each function of the canal and otolith in the vestibular system and evaluate subjective symptoms during postural change. Eye movement induced by various types of rotation was measured in normal subjects. Nystagmus with fast component corresponding to direction of rotation was occurred by sinusoidal earth vertical axis rotation, and the gain of eye movement in vestibuloocular reflex (VOR) was lower than in visual vestibuloocular reflex (VVOR) and higher than in visual fixed vestibuloocular reflex (VFX). Degree of dizziness was proportioned to degree of gain. off-vertical axis rotation was produced severe dizziness than earth vertical axis rotation. These results suggest stimulation of the otolith should be minimized to make a stable and pleasant condition in work and travel.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2019년도 춘계학술발표대회
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• pp.678-681
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• 2019

어지럼증은 모든 사람들이 일상생활에서 겪는 가장 흔한 질병 중 하나이다. 이러한 어지럼증은 주로 전정 기관의 약화 및 충격으로 인한 다양한 원인에 의해 유발되며 전정 재활을 통해 회복 될 수 있다. 전정 재활은 다양한 형태로 존재하지만 모든 사람을 위해 수행 할 수 있는 보편적 인 방법으로 훈련의 목적은 눈, 머리 및 균형 운동을 통해 전정 기관을 반복적으로 운동하는 것이다. 그러나 이러한 재활은 지루하고 흥미가 없으므로 환자가 계속 훈련을 하고 제대로 수행하고 있는지 확인하는 것이 어렵다. 이러한 문제점을 해결하기 위해 본 연구에서는 Unity3D 및 FOVE HMD를 사용하여 재미있고 평가 가능한 가상 현실 전정 재활의 내용을 구현했다.

• Research in Vestibular Science
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• 제17권4호
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• pp.167-169
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• 2018

Rotatory vertebral artery syndrome (RVAS) is characterized by recurrent attacks of vertigo, nystagmus, and syncope induced by compression of the vertebral artery during head rotation. A 60-year-old man with atlas vertebrae fracture presented recurrent attacks of positional vertigo. Left-beat, upbeat and count clock-wise torsional nystagmus occurred after lying down and bilateral head roll (HR) showing no latency or fatigue. Magnetic resonance imaging revealed foramen magnum stenosis (FMS) and dominancy of right vertebral artery (VA). The flow of the right VA on transcranial Doppler decreased significantly during left HR. The slower the velocity was, the more the nystagmus was aggravated. RVAS can be evoked by FMS causing compression of the VA. And the nystagmus might be aggravated according to the blood flow insufficiency.

• Annals of Clinical Neurophysiology
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• 제21권2호
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• pp.94-97
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• 2019

The patients with myotonic dystrophy (MD) show ocular motor abnormalities including strabismus, vergence deficits, and inaccurate or slow saccades. Two theories have been proposed to explain the oculomotor deficits in MD. The central theory attributes the defects of eye movements of MD to the involvement of the central nervous system while the muscular theory attributes to dystrophic changes of the extraocular muscles. A 58-year-old woman with MD showed selective slowing of horizontal saccades and reduced peak velocities for both horizontal canals in head impulse tests, while smooth-pursuit eye movements and vertical head impulse responses were normal. This case suggests that the extraocular muscles-as a final common pathway of the voluntary saccade and reflexive vestibular eye movements-may better explain the defective rapid eye movements observed in MD.

• Journal of Species Research
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• 제8권1호
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• pp.113-115
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• 2019

In this study, we present new records to Korea for three ciliate species[Apogonostomum pantanalense Foissner, 2016; Keronopsis polychaeta (Borror, 1966) Jankowski, 1979; Frontonia canadensis Roque and Puytorac, 1972] collected from marine (F. canadensis) and moss-covered soil(A. pantanalense and K. polychaeta) habitats. We examined the morphology of these three ciliates based on live observations and protargol impregnation. The main characters of the three ciliates are as follows: A. pantanalense: cell size approximately $130{\times}45{\mu}m$, tail-like posterior end, and 6 or 7 ventral cirral pairs elongated to transverse cirri; K. polychaeta: size approximately $140{\times}90{\mu}m$ and approximately 18 frontal coronal cirri and 5 transverse cirri; F. canadensis: cell size approximately $100{\times}50{\mu}m$ and approximately 88 somatic kineties, 3 or 4 vestibular kineties, and 5 postoral kineties.

• 대한수의학회지
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• 제61권4호
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• pp.35.1-35.4
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• 2021

Following intravenous (IV) administration of diazepam as a preanesthetic agent, sudden balance impairment, such as falling, leaning, and rolling, was identified in 2 canine cases. The 2 dogs were anesthetized for brain magnetic resonance scan to diagnose about a history of head tilt. After end of the diagnostic procedures, during the anesthetic recovery period, balance impairment was also observed. However, the symptoms gradually ceased by IV administration of flumazenil. These 2 canine cases indicated that diazepam premedication was responsible for the acute balance impairment.

• 항공우주의학회지
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• 제30권1호
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• pp.1-2
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• 2020

In commemoration of Vol. 30, Issue 1, our journal prepares four review articles and two original papers. The first review article provides guidelines for medical treatment for emergencies in an aircraft furing flight. This guideline addresses the resources and medical equipment available to physicians on board, common medical conditions, how to deal with them, including legal issues. The second review article covers historically meaningful animals that have contributed to aerospace research and the role of a veterinarian. The third one describes cardiovascular, musculoskeletal, and vestibular physiological effects of microgravity on the human body. As we are about to enter an aging society, the fourth review article introduces guidelines for safe overseas travel for senior passengers. The role of the aviation medical examiner is to maintain aircrew's health and to help them work long and healthy. In this regard, Choi et al. analyzed the physical examination data and sick leave data of an airline. Han et al. investigated the aerospace medical examination data of the Republic of Korea and suggested a solution to some common health problems of the crew.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• 제56권12호
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• pp.749-753
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• 2013

Basically stem cells have characteristics of multi-potency, differentiation into multiple tissue types, and self-renew through proliferation. Recent advances in stem cell biology can make identifying the stem-cell like cells in various mammalian tissues. Stem cells in various tissues can restore damaged tissue. Stem cells from the adult nervous system proliferate to form clonal floating colonies called spheres in vitro, and recent studies have demonstrated sphere formation by cells in the tympanic membrane, vestibular system, spiral ganglion, and partly in the organ of Corti. The presence of stem cells in the ear raises the possibilities for the regeneration of the tympanic membrane & inner ear hair cells & neurons. But the gradual loss of stem cells postnatally in the organ of Corti may correlate with the loss of regenerative capacity and limited hearing restoration. Future strategies using endogenous stem cells in the ear can be the another treatment modality for the patients with intractable inner ear diseases.