본 연구의 목적은 임상의 핵의학, PET 진단 분야에서 진단 시에 사용되는 방사성 동위원소 중 18F를 이용하여 납가운의 두께 별 에너지스펙트럼을 측정하고 납가운 0.3, 0.5mmPb에 대한 차폐율을 측정하고자 하였다. 에너지 스펙트럼 측정의 경우 자체 제작한 방법으로 측정하였고 차폐율 및 선량 측정의 경우 납가운과 선원의 거리에 대 해 선원과 측정기에 대해 납 가운의 위치를 달리 하여 3가지 조건으로 나누어 각각 20회씩 측정을 하여 평균값을 산출하였다. 에너지 스펙트럼 상에서는 납가운을 위치하 였을 때 본래 방사성 동위원소로부터 방출되는 에너지 외의 에너지 피크영역이 측정 되었고 차폐율 및 선량측정에서는 방사성동위원소 18F은 납가운을 이용하여 차폐를 할 경우 차폐율이 매우 미비하거나 음수의 값이 측정되었다.
Unlike accidents on land, marine accidents can not be supported rapidly from the outside. For this reason, The initial response and damage control system are critical. Cruise Lines International Association (CLIA) reported the necessity of the damage control system to IMO in the early 2000s. Even though the installation of these systems is not compulsory, the damage control system is installed and operated in about 60 cruises. The key component of damage control system is supporting the decision-making using 'KILL Card'. The purpose of study is to develop the shipboard training scenario for the foundation of 'KILL Card'. We made scenarios for fire and flooding through the analysis on existing scenarios, marine accident case and relative regulation. The suggested shipboard training scenario based on damage control system enables the crew to response with rapid decision-making to damage in emergency situations.
The research on improvement of false alarm from the automatic fire detection system has been continually achieved in the meantime. But the research for the code-transmitter as one of component devices of the automatic fire detection system. In order to improve difficulty of the code-transmitter check-up, introduction for the address type-code-transmitter and the automatic recovery system for check up of the code-transmitter was proposed. In order to prevent against occurrence of noise and signal attenuation, introduction of the optical fiber cables that noise and signal attenuation do not occur and introduction for an optical communication relay that can apply to was proposed respectively.
In addition to improving economic growth and development of advanced production technology brings many benefits to our society, but if the growth of this still has the shadow of accidents exists. In particular, the construction site has seen a significantly higher accident rate figures despite efforts on disaster prevention. Among the various methods of reducing the need for disaster safety education industry it has become very stressed its importance through many studies. When a disaster causes significant share of the construction industry due to the lack of educational causes, including technical causes, managerial causes, classification and educational causes of this ateumyeo safety awareness and knowledge account for large proportion. In the health and safety education, centered on the subjects of education supervisors will be able to reduce the real and effective industrial disaster education should be run.
CT scan 시 X-ray tube는 환자를 중심으로 360° 회전을 하기 때문에 산란선은 모 든 방향에서 발생한다. 임상에서 환자의 피폭을 감소시키기 환자의 흉·복부 전면만을 차폐하고 환자 후면이나 측면에서 발생되는 산란선에 대한 차폐는 시행하고 있지 않 다. 두부(Brain) CT 검사 시 흉부 및 복부에 입사되는 산란선을 ion chamber로 측정 하여 그 분포를 확인하고 두부 CT 검사 시 발생되는 산란선의 분포를 통해 기존 차폐 방법의 적정성을 평가 하고자 한다. 연구결과 gantry angle이 클수록, 전면보다 후면에 서 산란선이 많이 발생했다. 두부 CT 검사 시 발생되는 산란선에 의한 피폭을 최소화 하기 위해 가급적 gantry angle을 작게 줄 수 있도록 환자 두부의 위치를 조정하여 검 사를 하거나 납치마를 이용하여 환자의 흉·복부를 차폐할 경우 전면 뿐 아니라 양 측 면과 후면을 납치마를 이용하여 차폐를 해야 할 것이다.
The blast hole has a space between explosive and hole wall, and blast forces reaches the hole wall face with a large amount of loss during passing through this space. The loss ratio of blasting forces are different to this packing material of space like air, water, etc. In this study, the effect of packing materials is investigated by the numerical simulation analysis. The simulation is carried out to two phases; 1st phase is to compute the impacting forces reaching on the wall face passing through packing materials(air, water), 2nd phase is to study the blasting effect(block size of cracking, direction of driving forces, etc.) in real site. The reaching force at the wall face in the water is larger than in the air. This study shows that the water as packing materials is superior to the air.