Solid rocket motor (SRM) for anti-tank guided weapons has a lateral rocket nozzle as a structural feature. The lateral nozzle is twisted 30 degrees in the direction of flight. Due to the structural characteristics, it generates side forces in the direction of flight. The generated side forces cause forces and moments in the entire guided weapon, affecting missile stability and accuracy during flight. Therefore, it is very important to accurately measure the force and moment during the development and production of SRM. For example, in quality specification, acceptance criteria for thrust, side force, and moment were written. This study introduced a method for measuring thrust, side force, and moment of SRM using 6- component sensor. Depending on the size of the 6-component sensor and configuration of test device, results measured in the same SRM differed. During designing of the test device, structural stability and natural frequency must be grasped, and through this, it is possible to manufacture a measuring device that does not disturb the SRM. In this study, simply purchasing a sensor with high performance for precise measurement was not the answer. Instead, the measurement accuracy was increased by properly configuring the test device to suit the measuring environment.

Social activities of the elderly have been increasing as our society progresses toward an aging society. As their activities increase, so does the occurrence of falls that could lead to fractures. Falls are serious health hazards to the elderly. Therefore, development of a device that can detect fall accidents and prevent fracture is essential. In this study, we developed a portable fall detection system for the fracture prevention system of the elderly. The device is intended to detect a fall and activate a second device such as an air bag deployment system that can prevent fracture. The fall detection device contains a 3-axis acceleration sensor and two 2-axis tilt sensors. We measured acceleration and tilt angle of body during fall and activities of daily(ADL) living using the fall detection device that is attached on the subjects'. Moving mattress which is actuated by a pneumatic system was used in fall experiments and it could provide forced falls. Sensor data during fall and ADL were sent to computer and filtered with low-pass filter. The developed fall detection device was successful in detecting a fall about 0.1 second before a severe impact to occur and detecting the direction of the fall to provide enough time and information for the fracture preventive device to be activated. The fall detection device was also able to differentiate fall from ADL such as walking, sitting down, standing up, lying down, and running.

The purpose of this study was to investigate the significant characteristics in spray of industrial etch-nozzle for the design of process. The experiment was carried out with different spray pressure and industrial nozzle in wet etch. The characteristics of liquid spray, such as axial velocity and sauter mean diameter measurements were obtained by PDA. And impact force was calculated from spray characteristics. It was found that the fluid with higher spray pressure resulted in the smaller SMD and the higher droplet velocity and impact force. The depth of etch was increased in case of high spray pressure. In the case of injection angle oscillated between 20°, the result indicated constant effect of etch. The correlation between the spray characteristics and etch ones were analyzed. The depth of etch had good positive correlation with axial velocity and impact force. The result clearly shows that the characteristics in wet etch are strongly related to the spray characteristics with process.