• The KSFM Journal of Fluid Machinery
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• v.12 no.1
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• pp.16-21
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• 2009

In the last five years, 91 accidents from portable gas ranges and non-refillable metallic gas cartridges have occurred. The gas cylinder installed with a relief valve was developed to prevent an explosive accident from the gas cartridge. In this study it was carried out to evaluate the safety of a gas cylinder mounted with a relief valve which can prevent an explosion. Under the real using condition and the extreme condition the gas cylinder is heated with an electric heater. Simultaneously, the operating pressure is checked and the suitability of releasing flux is evaluated. And the possibility of fire or explosion was tested when the gas was released from the relief valve at the real using condition. Using a numerical simulation method, the diffusion of butane gas released from a relief valve was visualized.

• Journal of ILASS-Korea
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• v.11 no.4
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• pp.228-233
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• 2006

There are two types of electric controlled fuel injection system in the gasoline engines of common vehicles. One is fuel return system and the other is fuel returnless system according to the methods of controlling injection pressures. It is important to understand the characteristics of these system in loaming and studying of engine, but it is very difficult without a special equipment in reality. The purpose of this paper is to develop the emulation system that can be compensated with the amount of injection fuel according to various driving conditions, battery voltage, cooling water temperature, and engine speed, may be appeared in real driving, and especially can analyze the difference between the electric signal controlling the amount of injection fuel and its result, and nullity injection duration. With the developed system, we can conveniently set various and completed driving condition and so can acquire the useful information such as non-uniformity rate and mass of injection fuel using waveform analysis and measurement modules. It must be a very useful and sophisticated system to instruct and learn the features and operating states of injection system, and to study f3r improving the performance of it.

• Journal of Energy Engineering
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• v.17 no.4
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• pp.212-217
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• 2008

This study carried out the safety evaluation of non-refillable butane can for portable gas range equipped with relief valve for prevention of explosion. The can is heated by electric heater at the real using condition and the extreme condition after installing at a portable gas range for checking the operating pressure and the evaluating suitability of releasing flux. And the possibility of fire or explosion was tested when the gas was released from the relief valve at the real condition. As a result of this safety evaluation test, a non-refillable butane can with relief valve prevents the can from exploding by control of internal pressure.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.5
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• pp.89-108
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• 2023

This study provides a comprehensive analysis of recent studies conducted on the topic of nowcasting in order to enhance the accuracy and promptness of official statistical data. Furthermore, we propose an alternative approach involving the utilization of real-time data and its corresponding collection methods to effectively operate a real-time nowcasting model capable of accurately capturing the current economic condition. We explore high-frequency real-time data that can predict economic indicators in both the public and private sectors and propose a pipeline for data collection processing and modeling that is based on cloud platforms. Furthermore we validate the essential elements required for the implementation of real-time nowcasting, as well as their data management protocols to ensure the reliability and consistency needed for accurate forecasting of official statistical indicators.

• The Journal of Korean Physical Therapy
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• v.31 no.4
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• pp.228-235
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• 2019

Purpose: This study examined the injury and rehabilitation of athletes with disabilities in racket sports projects (i.e., badminton, table tennis, and wheelchair tennis). In addition, the characteristics of each project and the differences among those projects are discussed. Methods: Business team athletes with disabilities in racket sport were enrolled as subjects (i.e., 19 badminton athletes, 19 table tennis athletes, and 19 wheelchair tennis athletes). The real conditions of the injury, injury severity, injury site, symptoms, and rehabilitation methods after injury were analyzed. Results: No significant differences were observed among the actual condition, injury severity, symptoms and the methods of rehabilitation on racket sport for athletes (i.e., badminton, table tennis, and wheelchair tennis athletes) with disability. The differences were focused mainly on the injury sites due to the characteristics of the different projects, and specific technical actions. Conclusion: This study examined the real condition of the injury, injury severity, injury site, symptoms and rehabilitation methods after the injury on the rackets (i.e., badminton, table tennis, and wheelchair tennis) athletes with disabilities. The data can be used to eliminate the incidence of injury and minimize the injury severity for racket athletes with disabilities. In addition, it can also be used for the disabled, who like racket projects, as the fundamental material to prevent injury and assist in recovery.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.4
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• pp.127-134
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• 2013

While there are many services that can check current traffic condition and application program such as bus arrival alarm are developed, since it only provide simple alarm and check level of information, it is still insufficient in many senses. Therefore, the program that try to develop in this study is the system that predict arrival time to destination and inform the bus passengers by applying real time traffic information. The system developed related to this study is still very inadequate. In the system developed in this thesis, when the user input the current bus number and destination using smart-phone, relevant server acquire the bus route information from bus information DB, and analyze real time traffic information based on the information from traffic information DB, and inform customer of expected arrival time to destination. In this thesis, traffic congestion can be eased off and regular operation of public transportation can be improved with reliable destination arrival alarm. Also, it is considered that pattern of bus users can be analyzed by using these information, and analyzing average transport speed and time of public transportation, travel time depending on various situation can give a boost to study related to transportation information and its development.

• Physical Therapy Rehabilitation Science
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• v.10 no.1
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• pp.82-89
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• 2021

Purpose: This study is to investigate the muscle activity based on real-time visual feedback training methods by rehabilitative ultrasound image in elderly and correlation between Heckmatt scale grade, muscle tone and thickness. Design: Cross-sectional study: Pilot study Methods: 6 elderly participated in the study with 2 conditions. Under the condition of rehabilitation ultrasound imaging equipment, all subjects performed voluntary maximal muscle contraction of the quadriceps 3 times using visual feedback based on Rehabilitative Ultrasound Imaging 1.0 (RUSI 1.0). Under the condition of only ultrasound images, all subjects performed voluntary maximal muscle contraction of the quadriceps 3 times using ultrasound image-based visual feedback. The muscle thickness and tone of the quadriceps were measured and the grades were classified by Heckmatt scale and all variables were comparative analyzed. Results: Heckmatt scale grade showed a negative correlation with muscle thickness at relaxation (p<0.05), and a negative correlation with the difference value obtained by subtracting muscle thickness at relaxation from muscle thickness at contraction in ultrasound image condition (p<0.05). The muscle tone during relaxation showed a negative correlation with the muscle thickness during relaxation (p<0.05). Conclusion: In the case of voluntary maximum muscle contraction of the quadriceps muscle in the elderly, it can be seen that the muscle thickness is getting larger when the RUSI 1.0-based visual feedback is provided than with only ultrasound image provided. And the lower Heckmatt scale grade is, the thicker the muscle is, and the lower the muscle tone is.

• Bulletin of the Society of Naval Architects of Korea
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• v.25 no.1
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• pp.21-32
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• 1988

An experimental study was carried out to identify the fatigue fracture behavior of steel for merchant ships. The bending and shear loads were applied simultaneously on the specimens to simulate of real load condition for a ship. The effects of the stress intensity factor under mode I with mode II loading condition on the initiation and the propagation of a crack were investigated, with particular emphasis on mode II. When the $K_{II}$ stress intensity factor in mode II was applied under mode I loading condition, the propagation behavior of a crack is to be affected mainly by the anisotropic characteristic of materials.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.128-129
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• 2012

This paper proposed the wind turbine simulator for comparative study of the MPPT controls. The development of this wind turbine simulator is based on the torque controlled induction motor. The torque reference is obtained from a mathematical model of wind turbine whereas the inputs are rotor speed, wind speed and fixed-value of pitch angle. By using this wind turbine simulator, the real wind is not needed. Wind speed information can be stored and regenerated anytime. Hence it is possible to apply the same wind speed condition to different MPPT controls. With the same wind speed condition, it can fairly compare the advantages and disadvantages of the MPPT controls. The proposed wind turbine simulator is verified through PSIM simulation.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.123-134
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• 2013

Strengthening vehicle emission regulation is one of important policies to improve air quality in urban area. Due to the limitation of specified driving cycles for certification test to reflect real driving conditions, additional off-cycle emission regulations have been adopted in US and being developed in Europe. The driving cycles of US or Europe have been used in emission certification for Korean light-duty vehicles, but it has not been known how well the driving cycles reflect various real driving patterns in Korea. In that point of view, it is required to estimate vehicle emission based on real road driving conditions to raise the effectiveness of vehicle emission regulation in Korea. In this study, real driving emission measurements have been conducted for three Korean light-duty vehicles with PEMS. The driving routes consisted of urban, rural and motorway in Seoul and Incheon. The data have been analyzed with various averaging methods including moving averaging windows method and compared to emission limits set with emission certification modes applied to tested vehicles. The results have shown that the real driving pollutant emissions of a gasoline and a LPG vehicles have been ranged quite lower than those of emission limits on CVS-75 driving cycle. But real driving NOx of a light duty diesel vehicle has been considerably higher than emission limit of NEDC driving cycle. The higher than expected NOx emission of a diesel vehicle might be caused by different strategy to control EGR in real driving condition from NEDC driving.