• 수산해양교육연구
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• 제28권1호
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• pp.14-21
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• 2016

Research on ship motion and seasickness is recognized as the important research area to ensure the pleasant operative environment in addition to the research of operation safety of ship. In this paper, the motion performance in waves for the training ship Kaya of Pukyong National University is obtained by using the computer program based on Strip Method. To guarantee the pleasant seafaring in ocean, the vertical acceleration of ship motion is calculated according to the habitation division location in the ship. The results of calculation by changes of location of habitation division are compared with the guideline of MSI(Motion Sickness Incidence). The degree of motion sickness is shown and discussed through the comparison between calculated vertical acceleration spectrum and MSI guideline. To improve the safety of ship in motion and the pleasant seafaring in waves, the downtrend of seasickness ratio is needed by the decrease on vertical acceleration of the ship. Through the results in this paper, the relocation of both bridge and accommodation toward the aftship reduced the vertical acceleration and MSI.

• 수산해양교육연구
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• 제26권4호
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• pp.686-694
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• 2014

Research on ship motion and seasickness is recognized as the important research area to ensure the pleasant operative environment in addition to the research of operation safety of ship. In this paper, The motion performance in waves for the training ship Kaya of Pukyong National University is obtained by using the computer program based on Strip method. To guarantee the pleasant seafaring in ocean, the vertical acceleration of ship motion is calculated according to the hull form modification. The results of calculation by changes of hull form are compared with the guideline of MSI(Motion Sickness Incidence). The degree of motion sickness is shown and discussed through the comparison between calculated vertical acceleration spectrum and MSI guideline.

• 산업경영시스템학회지
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• 제21권45호
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• pp.333-346
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• 1998

By progress of technology, it became possible for us to do many kinds of operations in virtual environment. However side effect is called simulator sickness may occur to human body when human come in contact with this new environment. It makes symptoms similar to motion sickness. Many studies about that were started in 1950s and have actively been progressing in other countries, but in Korea recognition about that field is insufficient. Main contribution of this paper would be the base study about phenomena of simulator sickness which may be occurs in simulator or virtual reality environment, factors which induce simulator sickness, and quantifying methods of simulator sickness.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권4호
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• pp.655-669
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• 2015

The Overall Motion Sickness Incidence is applied to the hull form optimization of a wave piercing high-speed catamaran vessel. Parametric hull modelling is applied to generate two families of derived hull forms, the former varying the prismatic coefficient and the position of longitudinal centre of buoyancy, the latter instead the demi-hull separation. Several heading angles are analysed in a seaway, considering all combinations of significant wave height and zero-crossing period under two operating scenarios. The optimum hull is generated and vertical accelerations at some critical points on main deck are compared with the parent ones. Finally a comparative analysis with the results obtained for a similarly sized monohull passenger ship is carried out, in order to quantify, by the OMSI, the relative goodness in terms of wellness onboard of monohulls and catamarans, as a function of sea states and operating scenarios.

• 한국항해항만학회지
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• 제32권1호
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• pp.15-22
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• 2008

바다에서 운항하는 선박은 바람과 파도 등의 외란 때문에 횡동요(Rolling), 종동요(Pitching), 상하동요(Heaving) 등의 운동을 하게 되며, 이러한 운동은 가속도 형태로 승객이 느끼게 된다. 따라서, 선박내의 특정 지점에서 좌우방향, 상하방향 가속도와 각속도 등을 계측하면 선원 또는 승객이 선박 운동에 어느 정도 피폭되었는가를 알 수 있다. 본 연구에서 개발한 운동 운항환경 모니터링 시스템은 4개의 가속도계와 가속도계, 자이로가 포함된 관성 자세계측장치, 데이터 취득장치를 포함한 계측 및 통신부, 중앙에서 데이터를 관리하고, 운항환경 지수를 계산하는 전산기로 구성되고, 계측된 가속도와 각속도를 이용하여 운항환경을 나타내는 정량적 지수인 뱃멀미 지수(Motion Sickness Incidence, MSI), 운동유발 작업방해회수(Motion Induced Interrupt, MII)를 실시간으로 계산한다. 개발된 시스템은 한국해양대학교 실습선인 한나라호의 부산-목포, 부산-제주 연안항해시 실선시험을 통하여 유효성을 확인하였다.

• The Journal of Korean Physical Therapy
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• 제36권1호
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• pp.39-44
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• 2024

Purpose: Cybersickness is a type of motion sickness induced by virtual reality (VR) or augmented reality (AR) environments that presents symptoms including nausea, dizziness, and headaches. This study aimed to investigate how cathodal transcranial direct current stimulation (tDCS) alleviates motion sickness symptoms and modulates brain activity in individuals experiencing cybersickness after exposure to a VR environment. Methods: This study was performed on two groups of healthy adults with cybersickness symptoms. Subjects were randomly assigned to receive either cathodal tDCS intervention or sham tDCS intervention. Brain activity during VR stimulation was measured by 38-channel functional near-infrared spectroscopy (fNIRS). tDCS was administered to the right temporoparietal junction (TPJ) for 20 minutes at an intensity of 2mA, and the severity of cybersickness was assessed pre- and post-intervention using a simulator sickness questionnaire (SSQ). Result: Following the experiment, cybersickness symptoms in subjects who received cathodal tDCS intervention were reduced based on SSQ scores, whereas those who received sham tDCS showed no significant change. fNIRS analysis revealed that tDCS significantly diminished cortical activity in subjects with high activity in temporal and parietal lobes, whereas high cortical activity was maintained in these regions after intervention in subjects who received sham tDCS. Conclusion: These findings suggest that cathodal tDCS applied to the right TPJ region in young adults experiencing cybersickness effectively reduces motion sickness induced by VR environments.

• 감성과학
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• 제21권4호
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• pp.43-54
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• 2018

본 연구는 멀미증상이 동공 리듬에 미치는 영향을 확인하는 것을 그 목적으로 하였다. 본 연구는 2D와 HMD를 통해 동일한 가상현실 콘텐츠를 실험참가자에게 15분 동안 경험하게 한 이후에 동공반응을 비교하였고 본 실험에는 16명(남자 8명, 여자 8명, 평균 나이: $25.67{\pm}2.43$세)의 피험자가 참여하였다. 연구 결과, 영상멀미를 경험한 이후에 동공 리듬이 불규칙한 패턴을 나타내었고 이것은 동공 크기(mPD) 및 동공 리듬의 편차(sPD)가 증가하는 결과로 확인되었다. 이러한 동공 반응의 결과는 인지부하와 밀접한 관련이 있고 영상멀미를 처리해야 할 시각 정보량의 증가 및 감각정보들 사이의 충돌 혹은 불일치로 인한 인지부하 현상으로 해석이 가능하다. 본 연구에서 제안된 방법은 기존의 센서 기반의 평가 방법에 비해 멀미 증상을 카메라 기반의 비접촉식으로 측정할 수 있는 가능성을 확인하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 추계학술대회
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• pp.25-27
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• 2014

황천 운항 중인 선박은 파도에 의한 과도한 운동과 그로 인한 슬래밍, 프로펠러노출, 갑판침수와 같은 현상으로 구조, 화물, 인명에 위험을 초래할 수 있다. 이 때문에 황천 시 선박은 안전 운항을 위하여 속도와 코스를 신중히 결정할 필요가 있다. 선박 운동 모니터링 시스템은 해상환경이 선박에 미치는 다양한 위험 상황을 사전에 예측하고 피할 수 있도록 의사 결정을 지원하며, 현재 선박의 운동상태와 구조적 안정성을 지속적으로 모니터링 함으로써 선박, 선원, 화물의 안전을 지원할 수 있도록 개발되었다. 본 시스템은 주파수 영역에서 New strip 방법에 기초하여 운동 응답과 수직 굽힘 모멘트를 계산하며, 슬래밍, 프로펠러노출, 갑판침수를 예측한다. 또한 선박 운동과 선체구조응력을 실시간으로 모니터링하여 과도한 선체운동이나 선체구조피로 등의 위험 상황을 표시하고 선원의 작업성과 승선감의 지표인 MII (Motion induced interruption), MSI (Motion sickness incidence)를 제공한다.

• Biomolecules & Therapeutics
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• 제16권2호
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• pp.161-167
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• 2008

Scopolamine patch is an effective anticholinergic and antiemetic agent for motion sickness in S. Korea. Since this medication is Over The Counter (OTC) medication and may cause serious side effects when misused. Therefore, we evaluate the safety and efficacy for scopolamine patch in this study. We selected and surveyed total 43 patients who purchased scopolamine patch from three different pharmacies located at S and C Express Bus terminals and P Port at Seoul, Cheongju, and Busan. In the result, 11 patients (8${\sim}$15 year old:25.6%) were correctly used scopolamine patch with a children dose and 2 patients were misused. 26 (15${\sim}$60 year old: 60.4%) and 4 (over 6o year old: 9.3%) patients were correctly used with a adult dose. 33 patients (69.9%)answered that they knew the directions well how to use scopolamine patch correctly. Only 24.2% (n=8) patients learned the directions by pharmacist's consultation. Most patients (45 frequencies with duplicate counts) had some experienced side effects and among those drowsiness is the most common one. In conclusion, scopolamine patch as a non-prescription drug (OTC) should be monitored by pharmacist with correct drug consultation.

• 제어로봇시스템학회논문지
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• 제15권8호
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• pp.823-830
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• 2009

For developing automotive parts and telematics devices the real car test often shows limitation because it needs high cost, much time and has the possibility of the accident. Therefore, a Vehicle Driving Simulator (VDS) instead of the real-car test has been used by some automotive manufactures, research centers, and universities. The VDS is a virtual reality device which makes a human being feel as if one drives a vehicle actually. Unlike actual vehicle, the simulator has limited kinematic workspace and bounded dynamic characteristics. So it is difficult to simulate dynamic motions of a multi-body vehicle model fully. In order to overcome these problems, a washout algorithm which restricts workspace of the simulator within the kinematic limits is needed, and analysis of dynamic characteristics is required also. However, a classical washout algorithm contains several problems such as time delay and generation of wrong motion signal caused by characteristics of filters. Specially, the classical washout algorithm has the simulator sickness when driver hardly turns brakes and accelerates the VDS. In this paper, a new washout algorithm is developed to enhance the motion sensitivity and improve the simulator sickness by using the vehicle tilt signal which is generated in the real time vehicle dynamic model.