Feasibility Study of Heavy-ion Beams and Compound Target Materials for Muon Production

손재범,이주한,김기동,김용균 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.67 No.8

We have investigated the feasibility of using compound materials as targets for muon production by virtue of simulations using a GEANT4 toolkit. A graphite material and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C), were considered as muon production targets, and their muon production rates for a 600-MeV proton beam were calculated and compared. For the thermal analysis, the total heat deposited on the targets by the proton beams and the secondary particles was calculated with the MCNPX code; then, the temperature distribution of target was derived from the calculated heat by using the ANSYS code with consideration of heat transfer mechanisms such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy-ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with the rates experimentally-obtained for a proton beam.

인산칼륨배합세치제의 상아질지각과민완화효과

손재범,성진효,김동기 대한구강보건학회 2003 大韓口腔保健學會誌 Vol.27 No.1

The desensitizing toothpaste which is containing potassium phosphate, sodium fluoride, ursodesoxycholic acid and tocopherol acetate was compared with other silica-base toothpastes for the treatment of dentinal hypersensitivity in a double-blind study. Of these, one acted as negative control containing only 1,000ppm of fluoride, another acted as positive control containing 5% postassium nitrate and 1,000ppm of fluoride, and the other acted experiment contained 2% monobasicpotassium phosphate, 3% dibasicpotassium phosphate, 0.02% UDCA, 0.05% tocopherol acetate and 1,000ppm of fluoride. 96patients who have dentinal hypersensitivity were randomly allocated to use those toothpastes for 8 weeks. Sensitivity was scored according to the response to thermal stimuli, tactile, evaporative stimuli. Recordings were made at baseline,1,3,5 and 8week. The statistical comparison showed that sensitivity duration of experimental group was reduced significantly compared to negative control group and positive control group(p<0.05). The clinical findings would be consistent with the in vitro observation that the experimental toothpaste occluded open dentinal tuble more effectively and increase the hardness of teeth more highly than positive control and negative control toothpastes.

원격제어 시스템

손재범,정완균,염영일 제어로봇시스템학회 1996 제어로봇시스템학회지 Vol.2 No.3

이 글에서는 원격제어 시스템의 역사, 적용에서 이론까지 간략하게 다루어 보았다. 과학기술이 발달하고 생활수준이 향상됨에 따라 인간은 소위 3D 직종을 기피하려는 경향을 갖게 되었다. 또한 작업환경의 변화가 심하고 위험한 심해저나 원자력 발전소, 우주공간에서의 작업 등은 인간이 맡게 되면 엄청난 인건비가 소요되고, 작업자의 안전을 보장할 수가 없게 된다. 로봇을 이용하여 이러한 작업들을 대치하게 될 경우 무엇보다도 작업자를 보호할 수 있다는 장점이 있다. 그러나 순간적인 판단과 작업을 반복하거나 돌발적인 사고에 대처하는 능력이 로봇에게는 절대적으로 부족하기 때문에, 반대급부적으로 원격 제어 시스템의 가치가 점점 높아지고 있다. 원격 제어 시스템은 우주공간, 방사능 지역 등에서의 작업시 인간을 보호하고, 작업의 효율성 증대에 기여할 뿐만 아니라, 최근에 활발히 연구가 진행되고 있는 초정밀 로봇을 이용한 원격 수술(telesurgery)이나 사람이 들 수 없는 무게를 작업자의 의도대로 다룰 수 있게 하는 등 인간의 한계를 극복하는 데도 큰 몫을 담당할 것으로 기대되기 때문에 계속적인 연구를 필요로 하고 있다.

인터넷 기반 u-Healthcare 관련 세계 정책 동향 및 시사점

손재범,이인준,한정현,손성용,박길홍 한국인터넷정보학회 2009 인터넷정보학회지 Vol.10 No.3

로봇을 이용한 경피 생체 검사

손재범,김광기,Son, Jaebum,Kim, Kwang Gi 대한의용생체공학회 2012 의공학회지 Vol.33 No.3

Biopsy is a type of histopathological examinations, in which a physician samples cells or tissues from a patient's suspicious lesion. Such a lesion frequently resides deep inside human body, and then a percutaneous biopsy is therefore performed using a thick needle with the assistance of medical imaging such as computed tomography(CT) and magnetic resonance imaging(MRI). Recently modern robotic technology is being introduced to percutaneous biopsy in order to reduce any possible human error and hazard on physicians caused by medical imaging. After medical imaging locates the exact location of lesion, an optimization algorithm plans the path for a biopsy needle. Subsequently, a robot system moves the biopsy needle to the lesion in accurate and safe way with the control of a practitioner or automatically. In this article, we try to look into the state-of-art of percutaneous biopsy using such robotic technology. We classified percutaneous biopsy robots by mechanical characteristics and by imaging technology. Then, advantage and disadvantage of each class type are described as well as the basic description, and a few representative designs for each type are introduced. Current research issues of robotized percutaneous biopsy are subjectively selected for the readers' convenience. We emphasize the basic technology of actuator and sensors compatible with imaging technology to conclude this review.

고출력 펨토초 레이저와 CR-39를 이용한 양성자 Radiography

손재범,이철호,최일우,김이종,남기환,강승우,김용균 대한방사선방어학회 2011 대한방사선방어학회 학술발표회 논문요약집 Vol.2011 No.11

2007년 정세와 주요 사업

손재범,Son, Jae-Beom 한국농업경영인중앙연합회 2007 한농연 Vol.58 No.-

Fine Phantom Image from Laser-induced Proton Radiography with a Spatial Resolution of Several μm

손재범,이철호,강정수,Doh-Yun Jang,박준식,김연호,김용균,최창일,김이종,최일우,성재희,이성구,정태문,이창렬,유태준,이종민 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.1

The advantages of a laser-driven proton acceleration have prompted studies of laser-induced protonradiography. As the CR-39 solid-state nuclear-track detector is suitable for measuring chargedparticles and can be used in proton radiography, we studied laser-induced proton radiography withthe CR-39 for several years, and we were able to obtain a spatial resolution of about 10 μm. For obtaining an image with a spatial resolution of a few μm, we investigated the effect of theCR-39 etching conditions on the spatial resolution and carried out imaging experiments using finephantoms. Experiments were performed using the 100-TW titanium-sapphire laser system at theAdvanced Photonics Research Institute of the Gwangju Institute of Science Technology. We havedemonstrated that images with a spatial resolution of about several μm can be achieved usinglaser-induced proton radiography.

협상에 따른 농업피해를 최소화하기 위한 우리의 대응

손재범 전국농업기술자협회 2004 농업기술회보 Vol.41 No.8

A Study on Visual Fatigue and Binocular Visual Function before and after Watching VR Image

손재범,이승환,임현성 대한시과학회 2019 대한시과학회지 Vol.21 No.4

Purpose : This study was designed to determine how VR video viewing using HMD devices had an effect on the visual function, EEG, and the visual fatigue. Methods : This study analyzed the 30 subjects(in their 20s to 30s) who used smart devices the most. They had to have no systemic and eye diseases and their corrected vision were 1.0 or higher. The far and near phoria test were repeated three times each using Howell cards(3m, 40 cm) and 6 Δ prism. The push-up testing to check near point of accommodation and the NPC test were repeated three times. EEG signals were recorded using a Quick cap with 62 Ag-AgCl electrodes and NeuroScan SynAmps. We analyzed the resting EEG data with eyes open and eyes closed using CURRY7, which was commonly used for EEG pre-processing. Results : There were significant differences in near point of convergence(p<0.001), near phoria(p=0.004), and AC/A ratio(p=0.023) after VR image viewing. Accommodation and far phoria were not significant differences. In the brainwave analysis, the relative power of the alpha 1 band(p<0.001) and the relative power of the alpha 2 band(p=0.003) showed the difference in anterior, middle, and posterior. After watching VR images, the simulator sickness questionnaire showed a significant overall difference(p<0.001). In the correlation analysis, alpha 1 band relative power was significantly correlated with near phoria(p=0.038) and AC/A Ratio(p=0.041). Alpha2 band relative power showed significant correlation with nausea(p=0.029), oculomotor(p=0.021), and disorientation(p=0.010). Conclusion : After watching VR images, NPC significantly increased and exophoria significantly increased in near. And there was a significant increase in the alpha wave. In addition, cyber motion sickness was felt by all subjects, and the degree of disorientation was the biggest increase.