• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1779-1784
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• 2010

Net washing in a fishery involves considerable labor and is a time-consuming process; it also causes severe environmental pollution. In this study, we developed a net hauler for washing fishing nets. This hauler can be used to simultaneously haul and wash the net. We devised the revolver structure of the net hauler in order to resolve the net slip problem. The net hauler can be used by itself for washing small-sized nets, or it can be used in an auxiliary washing step in case of a large-sized net. Further, the component installed in the net hauler for unraveling the net improves the net washing performance of an automatic net washer. During the experiments conducted using the prototypes of the new net hauler, the net did not slip and the desired washing performance could be achieved.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.5
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• pp.393-399
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• 2013

In this paper, a novel approach to estimate cohesive laws for the mode I fracture of the graphene is presented by combining molecular dynamic simulations and an inverse algorithm based on field projection method and finite element method. The determination of crack-tip cohesive laws of the graphene based on continuum mechanics is a non-trivial inverse problem of finding unknown tractions and separations from atomic simulations. The displacements of molecular dynamic simulations in a region far away from the crack tip are transferred to finite element nodes by using moving least square approximation. Inverse analyses for extracting unknown cohesive tractions and separation behind the crack tip can be carried out by using conservation nature of the interaction J- and M-integrals with numerical auxiliary fields which are generated by systematically imposing uniform surface tractions element-by-element along the crack surfaces in finite element models. The preset method can be a very successful approach to extract crack-tip cohesive laws from molecular dynamic simulations as a scale bridging method.

• Journal of Preventive Medicine and Public Health
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• v.37 no.3
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• pp.282-291
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• 2004

Objectives : The aim of this study was to investigate the functional status variables related to the care time of health professionals for patients in long-term care facilities. Methods : The functional stati of 1001 patients in 8 long-term care hospitals were examined by the Resident Assessment Instrument for Long-term Care Facility Version 2.0. The care time of health professionals for patients was calculated using data from a self-reported task survey by nurses, auxiliary nurses, private aides, doctors, physiotherapists and social workers. Results : The average care time per diem was 240.6 minutes. The care time by doctors, nurses and private aides were 11.0, 71.0 and 139.5 minutes, respectively. The lower the function of activities of daily living (ADL) and the greater the symptoms of extensive services, special care and clinical complexity, the more care time was served. On the contrary, the greater the symptoms of nursing rehabilitation, depression, cognitive disorder, behavior problem and psychiatry/mood disorder, the less care time was served. Age and gender were not significantly related to the care time. Conclusions : Developing a case mix classification system for elderly long term care patients may be helpful for both of patients and health care providers. The ADL, extensive services, special care and clinical complexity of variables should be considered in the development of a case mix system for the long term care of patients in Korea.

• Journal of The Korea Institute of Healthcare Architecture
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• v.14 no.4
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• pp.31-38
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• 2008

As people's interest in the increase of individual leisure time and health grows, their interest in sports is also growing day by day to improve their standards of living. In the midst of the social changes, people's awareness of the disabled's sports activities is changing as well. However, the disabled's full access to public sports centers is restricted due to the shortage of facilities, area and available programs in public sports centers including community gymnasiums. In order to solve this problem, rehabilitation sports centers have been built as part of public sports centers, but the number of rehabilitation sports centers is still small. Besides, the disabled find themselves uncomfortable when using rehabilitation sports centers because most of them are outdated and too small in size. To make matters worse, sports centers for the use of the disabled only have a negative effect on the disabled's making inroads into society by hampering them from being a part of social unification. This study made a comparative analysis on the areal state of indoor gyms and swimming pools, which are the main areal factors of rehabilitation sports centers and public sports centers. Based on this analysis, this study aims to propose a sports center use plan for both the disabled and non-disabled. As a result, the total floor area ratios of indoor gyms for the disabled were found to be higher than those of public sports centers. This is because many indoor gyms for the disabled are not well equipped with resting areas, auxiliary or supporting areas. Regarding swimming pools for the disabled, their total floor area ratios and areas were found to be lower than those of public sports centers because, in many cases, these swimming pools are used for the rehabilitation of the disabled in rehabilitation sports centers. For this reason, swimming area for individual leisure activity or hobby is insufficient.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.371-372
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• 2007

The major causes of electrical fire are classified to short circuit fault, overload fault, electric leakage and electric contact failure. The occurrence factor of the fire is electric arc or spark accompanied with electrical faults. Residual Current Protective Device (RCD), that is Earth Leakage Circuit Breaker(ELB) and Molded_case Circuit Breaker (MCB), of high sensitivity type used at low voltage wiring cuts off earth leakage and overload, but the RCD can't cut off electric arc or spark to be a major factor of electrical fire. As the RCDs which are applied low voltage distribution panel are prescribed to rated breaking time about 30[ms] (KS C 4613), the RCDs can't perceive to the periodic electric arc or spark of more short wavelength level. To be improved on such problem, this research development is proposed to a auxiliary control apparatus for RCD trip on electric arc or spark due to electrical fire. Some experimental results of the proposed apparatus is confirmed to the validity of the analytical results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.2
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• pp.445-451
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• 2014

Dual LED lantern, which is composed of two light sources in one lantern, can be utilized as an auxiliary light source when the main light source is in trouble. Nevertheless, there are no way to obtain status information of the system and control the light source if the current domestic standard protocol is applied, since the standards for dual LED lantern are not defined yet. Regarding to this problem, we suggested expanded lantern protocol for management system of dual LED lantern based on current domestic standard. Also, we confirmed the normal operation of dual LED lantern after implementing suggested protocol on the developed management system. Control system suggested and implemented in this study is tested not only its function of controlling and acquiring the operating status of dual LED lantern, but also its capability to utilize as a control system of currently used LED lanterns.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.523-529
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• 2019

In this study, we investigated the pretreatment technologies of volatile organic compounds (VOCs) which is a problem as the semiconductor and display industry develops recently. The conventional concentrator used in the direct combustion system, is easily contaminated by the exhaust gas in the manufacturing process of the display, resulting in the low treatment efficiency of generated VOCs. Physical/Chemical analyses of the exhaust gas showed high boiling point and viscosity in addition to a large amount of molecular weight alcohols and oil components. In this study, we tried to treat degrading materials by using the heat exchanger in a pretreatment facility and some materials degrading the concentrator were condensed more than 90%. In addition, it was also confirmed that an auxiliary device of the grease filter could remove the redispersion polymer oil from the heat exchanger.

• Journal of Korean society of Dental Hygiene
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• v.21 no.4
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• pp.441-453
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• 2021

Objectives: This study identified problems and improvements in projects targeted to dental workers in a child-adolescent dental care service. Methods: The subjects were 40 dentists, 43 dental hygienists, and 51 others who participated in service in Seoul. A self-administered questionnaire was used to address the problems and improvements in the project. Descriptive statistics, chi-square test, and one-way analysis of variance were performed using SPSS 23.0. Results: Oral examination was performed by 99.2% of dentists, and some service items such as professional tooth cleaning, fluoride application, and scaling were performed by dental auxiliary personnel regardless of legal duties. The problem was that the subjects took a lot of time in providing services, and students or guardians participating in the project refused to receive preventive dental services. As regards improvements, the insurance fee was the highest (48.1%), followed by the provision of regular services (38.8%), and system improvement and administrative support (35.7%). Conclusions: To activate a child-adolescent dental care service, it is thought that continuous efforts such as providing financial support by the government, education to increase participants' understanding, and social consensus for the participation of service providers and beneficiaries are required.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.12
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• pp.1027-1035
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• 2021

We presents a design of 3U cubesat MIMAN (Monochrome imaging for monitoring aerosol by nano-satellite) for aerosol monitoring mission with high spatial resolution. The main objective of MIMAN mission is to take images of aerosols around Korea and to provide auxiliary data for GK 2B cloud masking. For this mission, we derived mission requirements and constraints for the MIMAN mission. We designed the mission architecture and concept of operations. To reduce risk factors in space operation, we considered the safety of the communication. In every operation modes, UHF communication is available so that the cubesat can operate based on the ground commands. So, we can handle every problem at the ground station during mission operations. Based on the mission and concept of operations, we confirmed that the system design satisfied the system requirements. We designed the system interface considering data flow of each hardware, and evaluated the safety of the system with system budget analysis.

• Journal of Industrial Convergence
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• v.20 no.1
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• pp.63-68
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• 2022

In schools and corporate buildings, public WiFi Access Points are installed on the ceilings of hallways. In the case of an architectural structure in which a WiFi signal enters through a steel door made of a material with high signal attenuation, Internet connection is frequently cut off or fails when the door is closed. To solve this problem, our research implements an economical and portable WiFi extender using a Raspberry Pi and an auxiliary battery. Commercially available WiFi extenders have limitations in the location where the power plug is located, and WiFi extension using the WiFi hotspot function of an Android smartphone is possible only in some high-end models. However, because the proposed device can be installed at the position where the Wi-Fi reception signal is the best inside the door, the WiFi range can be extended while minimizing the possibility of damage to the original signal. Experimental results show that it is possible to eliminate the shadows of radio waves and to provide Internet services in the office when the door is closed, to the extent that web browsing and real-time video streaming for 720p are possible.