Development of application scenarios for smart mobile walker by in-depth focus group interviews and clinical expert meetings

Kiwan Han,Jeongsu Lee,Won-Kyung Song 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

Various robotic systems have been proposed for providing assistance in activities of daily living and support therapy. Our consortium simultaneously had developed an assistive robotic module, called a smart mobile walker, and its application scenarios on the basis of inputs obtained from candidate users and clinical experts during the entire robot development process. This paper presents the development of scenarios for examining the applicability of the robotic module in providing support for activities of daily living. Scenario construction is an essential process for embodying the target population, purpose, and performance of an assistive robotic system in its development process. To this end, in this study, we conducted an in-depth analysis of the feedback received during interviews of a focus group and clinical experts and consulted the International Classification of Functioning, Disability and Health. Finally, we developed eight scenarios for the smart mobile walker that were targeted at elderly people and stroke survivors.

감정표현 평가 시스템 개발 및 실험적 적용

한기완(Kiwan Han),김광욱(Kwanguk Kim),구정훈(Jeonghun Ku),장희정(Hee Jeong Jang),박준영(Junyoung Park),김인영(In Young Kim),김재진(Jae-Jin Kim),김찬형(Chan Hyung Kim),김선일(Sun I. Kim) 한국HCI학회 2006 한국HCI학회 학술대회 Vol.2006 No.2

Validity and Reliability of Cognitive Assessment Using Virtual Environment Technology in Patients with Stroke

Ku, Jeonghun,Lee, Jang Han,Han, Kiwan,Kim, Sun I.,Kang, Youn Joo,Park, Eun Sook Wolters Kluwer Health, Inc. All rights reserved. 2009 AMERICAN JOURNAL OF PHYSICAL MEDICINE & REHABILITA Vol.88 No.9

Ku J, Lee JH, Han K, Kim SI, Kang YJ, Park ES: Validity and reliability of cognitive assessment using virtual environment technology in patients with stroke. OBJECTIVES:: We assessed the validity and reliability of a virtual environment technology (VET)-based cognitive assessment program that was developed as a measurement tool of cognitive abilities in patients after a stroke. DESIGN:: Twenty participants diagnosed with stroke caused by unilateral brain lesions were enrolled to assess the VET program’s validity and test-retest reliability. Participants underwent evaluation by paper-based neuropsychological tests including the Korean Mini-Mental Status Examination, the Korean-Wechsler Adult Intelligence Scale, the Motor Free Visual Perception Test, Rey-Kim Memory Test, and Kim’s Frontal-Executive Neuropsychologic Test as well as the VET-based cognitive assessment. Major variables and indices of the VET program were calculated. The VET program validity was evaluated using a simple correlation analysis between variables from the VET program and conventional paper-based neuropsychological measurements, and the reliability was evaluated by investigating the test-retest correlation coefficients. RESULTS:: Major variables and indices of the VET program in patients with stroke correlated significantly with the related scores of paper-based neuropsychological tests. In addition, the test-retest reliability analysis revealed that the correlation coefficients ranged from 0.528 to 0.926. CONCLUSION:: The VET-based cognitive assessment program showed adequate reliability and validity as a method of cognitive assessment in patients after stroke.

VR-Based Conversation Training Program for Patients with Schizophrenia: A Preliminary Clinical Trial

Ku, Jeonghun,Han, Kiwan,Lee, Hyung Rae,Jang, Hee Jeong,Kim, Kwang Uk,Park, Sung Hyouk,Kim, Jae Jin,Kim, Chan Hyung,Kim, In Young,Kim, Sun I. Mary Ann Liebert 2007 Cyber Psychology & Behavior Vol.10 No.4

Root Barrier and Fertilizer Effects on Soil CO₂ Efflux and Cotton Yield in a Pecan-Cotton Alley Cropping System in the Southern United States

Lee, Kye-Han,An, Kiwan Korean Society of Forest Science 2006 한국산림과학회지 Vol.95 No.2

Little information is available on soil $CO_2$ efflux and crop yield under agroforestry systems. Soil $CO_2$ efflux, microbial biomass C, live fine root biomass, and cotton yield were measured under a pecan (Carya illinoinensis K. Koch)-cotton (Gossypium hirsutum L.) alley cropping system in southern USA. A belowground polyethylene root barrier was used to isolate tree roots from cotton which is to provide barrier and non-barrier treatments. The barrier and non-barrier treatment was randomly divided into three plots for conventional inorganic fertilizer application and the other three plots for organic poultry litter application. The rate of soil $CO_2$ efflux and the soil microbial biomass C were affected significantly (P < 0.05) by the fertilizer treatment while no significant effect of the barrier treatment was occurred. Cotton lint yield was significantly (P < 0.0 I) affected by the root barrier treatment while no effect was occurred by the fertilizer treatment with the yields being greatest ($521.2kg\;ha^{-1}$) in the root barrier ${\times}$ inorganic fertilizer treatment and lowest ($159.8kg\;ha^{-1}$) in the non-barrier ${\times}$ inorganic fertilizer treatment. The results suggest that the separation of tree-crop root systems with the application of inorganic fertilizer influence the soil moisture and soil N availability, which in tum will affect the magnitude of crop yield.

Ecosystem Respiration as Influenced by Thinning in Red Pine Forest in Southern Korea

( Hyung Woo Lim ),( Kiwan Ahn ),( Woo Jung Choi ),( Kye Han Lee ) 한국임학회 2011 산림과학 공동학술대회 논문집 Vol.2011 No.-

상지재활 훈련동안 자기수용감각의 훈련 및 평가를 위한 가상현실 시스템 개발 : 예비 연구

조상우(Sangwoo Cho),구정훈(Jeonghun Ku),한기완(Kiwan Han),이형래(Hyeongrae Lee),박진식(Jinsick Park),이원호(Wonho Lee),신영석(Youngseok Shin),김홍준(Hongjoon Kim),강윤주 (Younjoo Kang),김인영 (Inyoung Kim),김선일(Sun I. Kim) 한국HCI학회 2008 한국HCI학회 학술대회 Vol.2008 No.2

Proprioception defined it as the ability to detect, the spatial position or movement of joints using balance, power of the muscle, agility in the internal parts of the body. In existing study for improvement of proprioception, reaching task training provided a feedback; the assessment was not provided a feedback. But, this has problem that it can not guide a proprioception from situation with visual feedback. Virtual reality technique can solve the problem of way providing feedback during training. In this study, we developed proprioception training program using virtual reality and pilot study is performed. VR task were composed three modes. In mode 1, real-time movement of the body was provided using visual feedback. In mode 2, body position was provided using visual feedback when participant have specific response. And in mode 3, body position was not provided. VR task is performed five sessions at each mode and one session performed one by one a three target. In the result of this study, the moving time toward the target from mode 3 was smaller than the moving time toward the target from mode 1 (p= 0.001). The correlation was statistically significant between mode 2 and mode 3 while be offering visual feedback position of mode 2 lsession. But, the correlation was not statistically significant between mode 2 and mode 3 after be offered visual feedback position of mode2 lsession (p = 0.012). Training environment of mode 1 shows which training used visual feedback than proprioception. Mode2 can execute training of proprioception because first session acquires visual feedback by proprioception. The next study will be verification of the system for training or assessment by clinical experiment. 자기수용감각은 신체 내부에서 몸의 발란스, 근육의 강도, 민첩성을 이용하여 공간의 위치나 관절의 움직임을 조절하는 능력으로 정의된다. 기존의 연구에서는 자기수용감각을 발달시키기 위하여 reaching 훈련을 이용한 시각적인 feedback을 제시하여 훈련을 하고 feedback을 차단하고 측정하는 방법이 사용했지만 시각적인 feedback이 있는 상황은 자기수용감각만 유도할 수 없는 문제점이 있다. 가상현실 기술은 훈련 동안 실시간으로 시각적인 feedback을 다양하게 제공하는 것으로 기존의 연구의 문제점을 해결할 수 있다. 본 연구에서는 가상현실 기술을 이용한 자기수용감각을 발달시키기 위한 훈련 및 평가시스템을 개발하고 파일럿 스터디를 하였다. 가상환경 task는 3개로 구성되었다. mode 1은 신체 움직임을 실시간으로 시각적인 feedback을 제시하는 환경이다. mode 2는 피험자의 반응에 의해서만 신체 움직임에 대한 시각적인 feedback을 제시하는 환경이다. mode 3은 시각적인 feedback을 제시하지 않는 환경이다. 가상환경의 task는 각 mode에서 3지점을 한 번씩 수행하는 것을 1회기로 5회기씩 수행하였다. 본 연구의 결과에서, target을 획득하기 위하여 이동하는 시간은 mode 3에서 mode 1보다 더 짧게 소요되었다(p=0.001). mode 2와 mode 3에서 1회기에서는 상관관계를 가지고 2-5회기 동안에는 mode 2와 mode 3에서 상관관계가 보이지 않았다(p = 0.012). mode 1의 환경에서는 훈련에 필요한 자기수용감각보다 시각적인 feedback에 의한 훈련이 진행되는 것을 볼 수 있다. mode 2는 첫 회기에서 자기수용감각에 의한 시각적인 feedback을 제공받을 수 있기 때문에 자기수용감각 훈련을 수행할 수 있다. 추후 연구는 시스템의 타당성 검증과 임상실험을 통한 훈련과 평가를 할 계획이다.

Development and Verification of an Alcohol Craving-Induction Tool Using Virtual Reality: Craving Characteristics in Social Pressure Situation

Cho, Sangwoo,Ku, Jeonghun,Park, Jinsick,Han, Kiwan,Lee, Hyeongrae,Choi, You Kyong,Jung, Young-Chul,Namkoong, Kee,Kim, Jae-Jin,Kim, In Young,Kim, Sun I.,Shen, Dong Fan Mary Ann Liebert 2008 Cyber Psychology & Behavior Vol.11 No.3

<P>Alcoholism is a disease that affects parts of the brain that control emotion, decisions, and behavior. Therapy for people with alcoholism must address coping skills for facing high-risk situations. Therefore, it is important to develop tools to mimic such conditions. Cue exposure therapy (CET) provides high-risk situations during treatment, which raises the individual's ability to recognize that alcohol craving is being induced. Using CET, it is hard to simulate situations that induce alcohol craving. By contrast, virtual reality (VR) approaches can present realistic situations that cannot be experienced directly in CET. Therefore, we hypothesized that is possible to model social pressure situations using VR. We developed a VR system for inducing alcohol craving under social pressure situations and measured both the induced alcohol craving and head gaze of participants. A 2 x 2 experimental model (alcohol-related locality vs. social pressure) was designed. In situations without an avatar (no social pressure), more alcohol craving was induced if alcohol was present than if it was not. And more alcohol craving was induced in situations with an avatar (social pressure) than in situations without an avatar (no social pressure). The difference of angle between the direction of head gazing and the direction of alcohol or avatar was smaller in situations with an avatar alone (social pressure) than in situations with alcohol alone. In situations with both alcohol and an avatar, the angle between the direction of head gaze and the direction of the avatar was smaller than between the direction of head gaze and the direction of the alcohol. Considering the results, this VR system induces alcohol craving using an avatar that can express various social pressure situations.</P>

가상현실에서의 아바타 음주권유가 갈망감 유발에 미치는 영향에 관한 연구

최유경(Youkyung Choi),조상우(Sangwoo Cho),한기완(Kiwan Han),구정훈 (Jeonghun Ku),정영철(Young-chul Jung),김재진(Jae-jin Kim),남궁기(Namkoong Kee),김인영(In-yong Kim) 한국HCI학회 2008 한국HCI학회 학술대회 Vol.2008 No.2

This study set out investigate what Kind of changes would be caused to the craving of alcohol dependent patients by stimuli through virtual reality in the preparation stage for drinking refusal training. With regard to stimulation, it included alcohol exposure, a positive situation, and a negative situation on the basis of drinking encouraging situations(social pressure) known as drinking stimulating situations for alcoholics. The purpose of the study is to provide fundamental materials for the development of new training programs to refuse alcohol and for the examination of the possibility of utilizing virtual reality technology as a new treatment and training tool for alcoholics. To this end, a virtual reality program was conducted involving 12 alcoholics admitted to Severance Mental Health Hospital in Gyeonggi province from December 2006 to September 2007. The data was dealt with various statistic analyses such as frequency analysis, Wilcoxon Matched-pairs Signed-Ranks Test using SPSS/WIN 11.5 The analysis results indicate that avatars encouraging drinking caused more craving than just the background, that the scenes with alcohol exposed caused more craving than the scenes with no alcohol exposed, and that there were no significant changes to craving according to a positive or negative situation. The results confirmed that training sessions using virtual reality presented a situation and environment of drinking pressure that's similar to the actual social pressure and that the virtual reality approach had enormous potential as an effective treatment tool when combined with the existing treatment techniques. 본 연구는 음주거절훈련을 위한 전 단계로 가상현실을 통한 자극 제시가 알코올 중독 환자의 갈망감에 어떠한 변화를 주는 지를 알아보고자 하였다. 본 연구결과를 통해 향후 음주 거절 훈련 프로그램의 개발 뿐만 아니라 알코올 중독 환자들을 위한 새로운 치료 및 훈련 도구로서의 가상현실기법의 활용 가능성을 알아보기 위한 기초적인 자료 제공을 목적으로 한다. 가상현실 자극은 알코올 중독자들의 음주유발 상황으로 알려진 음주권유(사회적 압력)상황과 알코올 노출 여부 그리고 긍정적 상황 부정적 상황으로 구성하였다. 대상자는 2006년 12월부터 2007년 9월까지 입원중인 알코올 중독 환자 12명이었으며 수집된 자료는 SPSS/WIN 11.5 프로그램으로 통계처리 하였으며, Wilcoxon Matched-pairs Signed-Ranks Test로 분석하였다. 분석 결과 배경에서 아바타의 음주권유 여부가 일반적인 배경만 제시되는 경우보다 더 높은 갈망감을, 알코올이 노출된 장면이 그렇지 않은 장면보다 더 높은 갈망감을 나타내었고 긍정적·부정적이냐는 상황은 유의미한 결과를 나타내지 못하였다. 이러한 결과를 토대로 가상현실을 활용한 훈련이 실제의 사회적 압력과 유사한 음주 압력 상황과 환경을 느끼도록 하며, 가상현실 기법이 기존의 알코올 치료 기법들과 연합되어 효과적인 치료 도구로써의 활용가능성을 많이 가지고 있다는 것을 확인 할 수 있었다.

Compact THz time-domain spectroscopy based on pre-chirped pulses from mode-locked Yb-doped fiber laser

Kim, Ji Su,Yang, Hyun Moon,Han, Sang-Pil,Moon, Kiwan,Park, Kyung Hyun,Jeon, Min Yong Elsevier 2018 Optical fiber technology Vol.45 No.-

<P><B>Abstract</B></P> <P>We report on a compact terahertz (THz) time-domain spectroscopy (TDS) system based on fiber-integrated log-spiral low-temperature-grown InGaAs photo-conductive antenna (PCA) modules pumped by pre-chirped pulses from a 1.03-μm mode-locked Yb-doped fiber laser. A mode-locked Yb-doped fiber laser based on a birefringent spectral filter was produced with 240 mW average output power and 2.68-ps pulse duration. The output pulse had high chirp because the mode-locked fiber laser was implemented in the normal dispersion region. Therefore, the 733-fs output pulse was pre-chirped using two parallel diffraction gratings to facilitate its use as an optical pump source with THz radiation. After propagating in the single-mode fiber, the pulse-width of the pre-chirped pulse was compressed to 331 fs and injected into fiber-integrated PCA modules to generate a THz wave. We successfully obtained a THz emission bandwidth of over 2.5 THz for 120 mm in free space using the compact THz measurement setup. THz radiation was achieved by easily aligning two fiber integrated PCA modules. Absorption lines for water vapor were observed at room temperature. We also observed absorption lines from a 30% α-lactose sample. We confirmed that the fiber-integrated PCA modules and mode-locked Yb-doped fiber laser have potential applications in compact and portable THz-TDS systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Compact and movable terahertz (THz) time-domain spectroscopy is demonstrated. </LI> <LI> Pre-chirped pulses from a mode-locked Yb-doped fiber laser has been demonstrated. </LI> <LI> THz emission bandwidth of over 2.5 THz for 120 mm in free space is achieved. </LI> </UL> </P>