• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 1998.04a
• /
• pp.255-263
• /
• 1998

Dust-free garment prevents contamination which otherwise is caused by skin and clothes to protect from dust or dirt. Therefore, it requires high performance and should function as a working clothes. Clothes are a medium between human and thermal environmental system, and it is required to study human enviroment to ensure comfortableness of clothes and to satisfactorily go along with enviroment .This study investigates the physical and physiological features of dust-free garment used in the clean room at a semiconductor factory in oredr to scientifically clarify what the dust-free garmint is as well as to contribute to the design and development of high performance material and clothes. Three kinds of dust-free fabrics (DFG-I, DFG-II, DFG-III) which are being developed by a local company are used to manufacture dust-free garment. These dust-free garments are dressed and tested in such an enviroment as similar to semiconmemts with temperature at 23${\pm}$1$^{\circ}C$ and humidity at 50${\pm}$5%RH in order to investigate the thermo physiological and psychological features of human body. The results of this study are as follows. The results of this study are as follows. 1.The mean skin temperature was significantly different among the clothes, subjects and experimental time. Temperature tends to rise from the time of exercising load. Continuous motion coupled sealed clothes prevents heat transmittance, and temperature rises in the order of DFG-l, DFG-ll and DFG-lll as time course. 2.As for the skin temperature by local timperature is minimun on the head and torso and increares remarkably at the terminal part of human body. 3. As for the body mass loss was significantly higher in DFG-lll than DFG-l and DFG-ll. 4. Though there is no significant difference in the temperature within clothes among the kind of clothes temperature is 1$^{\circ}C$ higher in the back. Temperature within all the dust-free garments 29.7$^{\circ}C$ in the back and 31.3$^{\circ}C$ in the chest which belong to the comfort zone(31-33$^{\circ}C$). The relative humidity is 39.7%RH in the chest and 33.8%RH in the back which is slightly below the comfort zone(40-60%RH) 5. The thermal sensation belong to the comfort zone regardless of the kinds of clothes. The subjects feels a slight fatigue as times goes. As for the subjective sense of subjects the mean skin temperature as well as temperature and humidity within clothes show similar tendency. This means that they relate with each other.

• Composites Research
• /
• v.28 no.4
• /
• pp.219-225
• /
• 2015

Air spoiler, which can reduce the drag during operation, can be considered as a possible means to reduce carbon dioxide emission and to increase fuel efficiency. In this study, a composite air spoiler was designed and tested by static and repeated loads. The Green Water Pressure of 0.1 MPa a ship experiences during operation was perpendicularly applied to the air spoiler. Air spoiler was manufactured with sandwich panel which has glass fabric face and balsa core. Multiple sandwich panels were assembled to steel frame by bolt joint. The joint was designed to have bearing failure and examined by static and fatigue tests. Tests showed that the designed joint has enough margin of safety to endure joint failure. The developed sandwich panel to air spoiler is planned to be applied to a large scale commercial ship.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.5
• /
• pp.61-71
• /
• 2011

To measure the fatigue of metallic objects at high speed vibration while non-contact precision displacement measurement on how to have a lot of research conducted. Noncontact high-speed vibration detection sensor of the eddy current sensors and laser sensors are used, but it is very expensive. Recently, High-speed vibrations detection using an inexpensive inductive sensor to have been studied, but is still a beginner. In this paper, a new design of an inexpensive inductive proximity sensor has been suggested in order to measure high frequency dynamic displacements of metallic specimens in a noncontact manner. Detection of the existing inductive sensors, detection, integral, and amplified through a process to detect the displacement noise due to weak nature of analog circuits and integral factor in the process of displacement detection is slow. The proposed method could be less affected by noise, the analog receive and high-speed signal processing is a new way, because AD converter (Analog to Digital converter) without using the vibration frequency signals directly into digital signals are converted. In order to evaluate the sensing performance, The proposed sensor module using non-contact vibration signals were detected while shaker vibration frequencies from 30Hz to 1,100 Hz at intervals of vibrating metallic specimens. Experimental results, Vibration frequency detection range of the metallic specimins within close proximity to contactless 5mm could be measured from DC to 1,100Hz and vibration amplitude of the resolution was $20{\mu}m$. Therefore, the proposed non-contact inductive sensor module for precision vibration detection sensor is estimated to have sufficient performance.

• The Journal of Korean Academy of Prosthodontics
• /
• v.48 no.1
• /
• pp.61-68
• /
• 2010

Purpose: This article attempted to determine the factors affecting the preload and screw loosening. Methods: Available clinical studies from 1981 to 2008 from the PUBMED that presented screw loosening data and review articles regarding screw joint stability were evaluated. Eleven studies dealing the biomechanical principles of the screw mechanics were reviewed. Moreover, the results of our data were included. Results: The frequency of screw loosening was consequently reduced due to the advancement in torque tightening with torque wrench, screw material, coating technique for reducing the frictional force, and thread design, etc. If preload in the screw falls below a critical level, joint stability may be compromised, and the screw joint may fail clinically. The types of fatigue failure of screw were divided to adhesive wear, plastic deformation, and screw fracture. Conclusion: An optimum preload is essential to the success of the implant-abutment complex. To maintain optimum preload, using a torque wrench and re-tightening at recall time were needed.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.1
• /
• pp.474-484
• /
• 2016

This study was performed to identify the effects of the improvement of brain function by CST on the elderly with the 2nd or 3rd grade of long-term care insurance service. A quasi-experimental design using a nonequivalent control group, pre-post test was used. A total of 12 elders (6 in the experimental group and 6 in the control group) were recruited. Upledger CST(10-Step Protocol) was performed on each subject for 50 minutes per session, once a week, for a total of 8 treatments over an 8 week period from Jan to Feb 2015. The brain function quotient was measured before the 1st CST and after the last CST by portable EEG measurement device using a 2 Channel neuro-feedback system. The data was analyzed by SPSS (Ver. 18.0) program. After CST intervention, the attention quotient (AQ), level of tension, anti-stress quotient (ASQ), emotion quotient (EQ) and brain quotient (BQ) of the experimental group was significantly better than that of the control group. These results showed that the CST was effective in reducing the level of fatigue by the AQ, increasing the physical and psychological stress relief by the ASQ, emotional balance by the EQ, and improving the total brain function by the BQ. Therefore, CST can be used as an effective intervention for improving the health and brain function of the elderly in health facilities.

• Journal of the Korean Institute of Gas
• /
• v.12 no.2
• /
• pp.69-76
• /
• 2008

Three failure cases of CNG composite vessels were reported since after January 2005. The 1st and 2nd accidents were indebted to vessel defect and installation mistake. The 3rd was caused by gas leak at pipe connections. In this paper various aspects were studied based on information of the three failure analysis, which must be improved for better safety of the CNG bus system. Overpressure region caused by vessel explosion was theoretically predicted and also assessed by PHAST program. Explosion of 120 l vessel under 20 MPa is equivalent to 1.2 kg TNT explosion. The predicted value by PHAST was more serious than theoretical one. However, actual consequence of explosion was much less than both of the predicted consequences. Since the CNG vessel was designed by the performance based design methodology, it is difficult to verify whether the required process and tests were properly conducted or not after production. If material toughness is not enough, the vessel should be weak in brittle fracture at early in the morning of winter season since the metal temperature can be lower than the transition temperature. If autofrettage pressure is not correct, fatigue failure due to tensile stress during repeated charging is possible. One positive aspect is that fire did not ocurred after vessel failure. This may be indebted to fast diffusion of natural gas which hindered starting fire.

• The Journal of the Convergence on Culture Technology
• /
• v.5 no.4
• /
• pp.387-394
• /
• 2019

In this study, in order to evaluate the damage and deterioration of the track components of sleeper floating track (STEDEF), the field samples(specimens) were taken from the serviced line over 20 years old, and the track components were visually inspected, and investigated by laboratory tests and finite element analysis. As a result of visual inspection, the damage of the rail pad and fastener was slight, but the rubber boot was worn and torn at the edges of bottom. The resilience pads were clearly examined for thickness reduction and fatigue hardening layer. As a result of spring stiffness test of rail pad and resilience pad, the deterioration of rail pad was insignificant, but the deterioration of resilience pad exceeded design standard value. Therefore resilience pad was directly affected by train passing tonnage. As a result of comparing the deterioration state of the field sample and the numerical analysis result, the stress and displacement concentration position of the finite element model and the damage position of the field sample were coincident.

• The Journal of Korean Institute of Information Technology
• /
• v.16 no.11
• /
• pp.51-59
• /
• 2018

The Multi-Mission Unmanned Surface Vehicle(MMUSV), which is manufactured using glass Fiber Reinforced Plastic(FRP) material, is designed to perform a surveillance and reconnaissance on the sea. Various navigation sensors, such as RADAR, RIDAR, camera, are mounted on a mast to perform an autonomous navigation. And a dummy gun is mounted on the deck of the MMUSV for a target tracking and disposal. It is necessary to analyze a strength for structures mounted on the deck because the MMUSV performs missions under a severe sea state. In this paper, a strength analysis of the mast structure is performed on static loads and lateral external loads to verify an adequacy of the designed mast through a series of simulations. Based on the results of captive model tests, a strength analysis for a heave motion of the mast structure is conducted using a simulation tool. Also a simulation and fatigue test for a mounting part between the MMUSV and the dummy gun are performed using a specimen. The simulation and test results are represented that a structure of the mast and mounting part of the dummy gun are appropriately designed.he impact amount are performed through simulation and experiments.

• The Journal of the Convergence on Culture Technology
• /
• v.5 no.3
• /
• pp.359-367
• /
• 2019

The purpose of this study was to investigate the effects of ingestion of rabies and ginseng fruit extracts on alcohol hangover, liver damage protection, fatigue recovery, and physical strength improvement. A total of 64 volunteers aged over 20 were participated in this study and the randomized and repeated measures design method was used to divide a group of participants with a random assignment. All participants were divided into 4 groups (n=16) treated with hoveni dulcis thunb extract + ginseng berry extract (ARI 1000), hoveni dulcis thunb extract, ginseng berry extract, and placebo. As a result of respiratory alcohol concentration change, the group treated with ARI 1000 was significantly lower than the group treated with hoveni dulcis thunb extract, ginseng berry extract, and placebo in 1 hour of drinking, and significantly lower than the placebo group in 2 hours and 3 hours of drinking (p<0.05). After 2 and 3 hours of alcohol consumption, blood alcohol concentration of the group treated with rabies ARI 1000 was significantly lower than those of the other 3 groups (p <0.05). In conclusion, ingestion of ARI 1000 before drinking may significantly reduce the respiratory and blood alcohol concentrations, which may induce an effect on the hangover effect.

• Journal of the Korean Applied Science and Technology
• /
• v.39 no.1
• /
• pp.115-131
• /
• 2022

The purpose of this study was to develop and examine the effect of the Health Promotion Education Program for the Auxiliary Police based on the PRECEDE-PROCEED Model. This study was conducted using a nonequivalent control group pretest-posttest design. Twenty-five participants were selected by convenience sampling method and assigned to the experimental group, and 26 participants were assigned to the control group. The data were collected from Auxiliary Police officer in D provincial Police Agency. All of participations completed questionnaires about self-efficacy, social support, availability of resources, health promotion behavior, quality of life and received the objective stress test. In addition, the experimental group completed 7 sessions of health promotion Education programs according to PRECEDE-PROCEED model for 5 weeks. Data were analyzed using the SPSS/WIN 21.0 Program. There was significant differences over time between the groups in terms of health promotion behavior (F=7.63, p<.001), autonomic nervous activity (F=29.24, p<.001), stress resistance (F=31.22, p<.001), stress index (F=22.42, p<.001), fatigue (F=12.87, p<.001), and quality of life (F=3.49, p=.042). The results may be crucial to develop strategy in order to decrease the disease prevalence as well as increase the participants' overall quality of life. As a result, the Health Promotion Education Program for the auxiliary police was proved to be an effective intervention in order to improve the quality of life. Therefore, the program may be a useful intervention for the auxiliary police.