A needle-free automatic injection syringe is a device that delivers drugs into the skin and tissues using a high-speed fluid jet without using an injection needle. This technology is attracting attention as an efficient means of vaccine delivery in the veterinary and livestock fields that reduce the risk of cross-infection and require mass vaccination. In particular, animal vaccination provides various advantages over conventional needle injection methods in terms of worker safety, inoculation speed, and maintenance cost. Among these drivers, Jet Injector Nozzle's flow path design is very important in needleless automatic injection syringes. This paper was conducted to solve the problem of pressure loss at the nozzle discharge side of the existing Jet Injector in designing the flow path of the animal vaccine-free automatic injection syringe nozzle. To this end, CAE was performed and the optimum design of the flow path required by the company was performed, and a large flow rate was possible in the optimal shape design, but this focuses on the nozzle flow path, which requires a review of design additions of cylinders and motors on the rear side.

A needleless automatic injection syringe (Jet Injector) is a device that delivers drugs into the skin and tissues using high-speed fluid jets without the use of injection needles. Jet Injector's core technology is to penetrate the stratum corneum of the skin by converting pressure energy generated in the driving unit into fluid kinetic energy, and structural loads and dynamic responses generated in this process directly affect the performance and durability of the device. Therefore, the structural mechanical design of the drive unit can be said to be a key factor in securing the reliability and injection accuracy of the Jet Injector. This paper is intended to provide the basis data for the basic design of the drive unit of the "Animal Vaccine-free Automatic Injection Syringe (hereinafter referred to as the "Jet Injector"), and this calculation data provides basic data for the design. Based on this, it is possible to design the drive unit according to various assumptions and given conditions, and the expected performance can be reasonably inferred according to the design.

In this study, a pulse jet engine that operates without a shutter valve was developed using a reflector. The pulse jet engine has the disadvantage of being noisy and low in efficiency compared to other engines, but has the advantage of a simple structure and no significant limitations on the fuel used, so research is being conducted to apply this engine to industrial fields such as biomass fuel conversion and boiler systems. Various research is being conducted as it becomes the basis of a pulse detonation engine. In this study, a pulse jet engine is designed, manufactured and tested successfully. The developed pulse jet engine can be used as a power source for various transportation methods such as vehicles and hovercraft through improvement.

항공기 연료 결함으로 인한 사고는 CICTT에서 규정하는 사고유형 34개 중 상위 13번째를 차지할 정도로 중요하다. 유통과정과 보관환경 등에 따라 수분이나 오염물질의 유입되어 항공기 사고가 발생하는 것으로 알려져 있다. 장기간 보관 항공유의 물성변화를 확인 하고자 JET A-1 항공유를 금속캔에 보관하여 6개월 이후의 변화를 관찰하였다. 그 결과 장기간 보관된 항공유는 품질기준을 만족하였으 며, 연료유의 안정성도 높은 것으로 확인되었다. 하지만 해양경찰 항공기와 같이 임무의 특성상 항공유를 선박과 육상 저장시설, 유조차 등에 분리하여 보관하고 있는 상황에서는 내외부 환경 변화로 인해 수분이나 오염물질의 유입 가능성이 높다. 또한, 오염물질에 대한 분 석은 현존 검, 증류성상 등으로 분석이 가능하지만 수분의 경우는 국내외 표준과 국내법령에서 물 분리지수를 통한 항공유의 수분 분리 능력을 판단할 뿐 수분함량에 대한 분석이 수행되지 않고 있다. 이에 수분함량에 대한 품질관리 기준을 추가하고 국내외 표준과 법령을 획일화하는 개정을 수행하여 항공 안전성을 확보해야 할 것이다.