• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.153-160
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• 2008

Personal noise exposure was assessed in railroad operators working in 40 operation units including the Gyeongbu line, Honam line, and Janghang line between 2004 and 2006. 8-hour TWA were assessed based on the MOL (Ministry of Labor) guideline on noise evaluation, and 17% of these measurements exceeded 85 dBA while 70% were over 80 dBA. When the ACGIH TLV is adopted, 40% of measurements were over TLV (85 dBA). The noise exposure risk of railroad operators was higher for diesel locomotive operation and longer operational distances; in addition, the risk was higher for passenger car operation compared to freight car driving. Given that in Korea, over the past 30 years diesel locomotives have provided most of the railway's motive power and that hearing protective equipment is not likely to be used by workers during operation, railroad operators are at a high risk of noise-induced hearing loss. The result of audiometric test among 568 railroad operators showed that 32.6% of those tested had a hearing threshold shift of more than 40 dB. In conclusion, this study calls for more fundamental measures including noise control countermeasures within the operation areas, development of equipment that generates less noise and adopting limitation on the operation distance for a work shift.

• The KIPS Transactions:PartC
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• v.9C no.3
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• pp.421-430
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• 2002

In this paper, we propose the integrated management system for computing resource such as personal computers, the interface of router, and server equipment. IRMS defines and analyzes the performance factors for system such as pc and router, also it manages assets for server equipment. Manager can make use of data for understanding conditions whether system is normal or not. We suggest a hierarchical integrated management architecture for resolving problems of scalability and managing efficiency in large domain networks.

• Journal of Preventive Medicine and Public Health
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• v.23 no.2 s.30
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• pp.216-223
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• 1990

To identify the factors influencing the charges per case of acute appendicitis and normal spontaneous vaginal delivery (NSVD), the personal data-base files and hospital-characteristics-reporting data files of Korea Medical Insurance Corporation were analyzed. One hundred and twenty-nine institutions were selected. The results of this study were as follows 1. The differences of charges per case with respect to hospital ownership, location, and equipment levels were statistically significant. 2. The results of multiple regression analysis revealed that bed capacity was the most significant variable in both diseases. 3. Ownership was significant variable in acute appendicitis. In NSVD, ownership and hospital equipment level were statistically significant. In conclusion, bed capacity was statistically the most significant variable in the analysis of charages per case. And we thought that the results of this study would influence the policy of the hospital bed supply.

• Textile Coloration and Finishing
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• v.26 no.2
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• pp.106-113
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• 2014

Work-related falls are a major problem in the construction and roofing industries. To avoid serious injury to the worker caused by high decelerations or forces, different systems to absorb the energy of a fall are implemented in personal protective equipment. In this study, shock energy absorber lanyard protection tube was prepared using high tenacity PET fiber, P-aramid fiber, and UHMWPE fiber, respectively. Dynamic load test and static load test, bursting strength test based on the Korea fall protection equipment standard(Korea Occupational Safety & Health Agency standard 2013-13) or conformity European safety test(CE : EN355) were conducted. Especially maximum arrest force by dynamic load test of energy absorber showed below 6,000N.

• Electric Engineers Magazine
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• v.228 no.8
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• pp.43-48
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• 2001

Wide use of non-linear loads such as personal computers, monitors, laser printers, variable speed drives, UPS systems and other electronic equipment have led to harmonics becoming #1 issue in the electrical industry today. Commercial and Industrial building power distribution systems, designed for the old, linear-style loads especially when found in high densities. Some common power system problems include overloaded neutral conductors, overheated distribution transfOlmers, high neutral-to-ground voltage, poor power factor and distortion of the voltage waveform supplying these loads. The power quality problems, particularly high voltage distortion, have been known to cause equipment downtime due to malfunctions and component failure.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1285-1293
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• 2008

Locking sheet is to display the contents of interlocking equipment for safe train drive in stations. It is being used as a basic information for interlocking equipment and for route control condition and the discussion for train operation between related parties. In spite of importance of this, there was no other way except depending on the work by hands from each stage(drawing, examination, discussion, approval) due to non-existing any tool. It is written it takes 30days from drawing to approval by procedures. However, it is required over the days in real time due to argument of each party. Furthermore on drawing of locking sheet, special conditions applied in accordance with situations of each station occasionally are different depending on the person in charge. Therefore, it is urgent to make up Logic Tree to accept special conditions of all stations. Automation Program for Drawing and Examination of Locking Sheet is to improve inefficient interlocking operation which was operated by hands in accordance with custom as automated system. The target of this program is to minimize the processing time and potential errors by personal work and set up standards for Logic Tree of special condition.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.956-963
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• 2020

Dose optimization for Radioactive Occupational Personal (ROP) is an important subject in nuclear and radiation safety field. The geometric environment of a nuclear facility is complex and the work area is radioactive, so traditional navigation model and radioactive data field cannot form an effective environment model for dose assessment and dose optimization. The environment model directly affects dose assessment and indirectly affects dose optimization, this is an urgent problem needed to be solved. Therefore, this paper focuses on an environment model used for Dose Assessment and Dose Optimization (DA&DO). We designed a multi-layer radiation field coupling modeling method, and then explored the influence of the environment model to DA&DO by virtual simulation. Then, a simulation test is done, the multi-layer radiation field coupling model for nuclear facilities is demonstrated to be effective for dose assessment and dose optimization through the experiments and analysis.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.3
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• pp.167-175
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• 2022

With the recent expansion of electric kickboards and bicycle sharing services, more and more people use them. In addition, the rapid growth of the delivery business due to the COVID-19 has significantly increased the use of two-wheeled vehicles and personal mobility. As the accident rate increases, the rule related to the two-wheeled vehicles is changed to 'mandatory helmets for kickboards and single-person transportation' and was revised to prevent boarding itself without driver's license. In this paper, we propose a wearable smart safety equipment, called SafetyHelmet, that can keep helmet-wearing duty and lower the accident rate with the communication between helmets and mobile devices. To make this function available, we propose a safe driving assistance function by notifying the driver when an object that interferes with driving such as persons or other vehicles are detected by applying the YOLO v5 object detection algorithm. Therefore it is intended to provide a safer driving assistance by reducing the failure rate to identify dangers while driving single-person transportation.

• Advances in aircraft and spacecraft science
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• v.9 no.6
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• pp.525-536
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• 2022

The current state of telecommunications infrastructure in the Arctic does not allow providing a wide range of required services for people, businesses and other categories, which necessitates the use of non-traditional approaches to its organization. The paper proposes an innovative approach to building a combined communication network based on tethered high-altitude platform station (HAPS) located at an altitude of 1-7 km and connected via radio channels with terrestrial and satellite communication networks. Network configuration and composition of telecommunication equipment placed on HAPS and located on the terrestrial and satellite segment of the network was justified. The availability of modern equipment and the distributed structure of such an integrated network will allow, unlike existing networks (Iridium, Gonets, etc.), to organize personal mobile communications, data transmission and broadband Internet up to 100 Mbps access for mobile and fixed subscribers, rapid transmission of information from Internet of Things (IoT) sensors and unmanned aerial vehicles (UAV). A substantiation of the possibility of achieving high network capacity in various paths is presented: inter-platform radio links, subscriber radio links, HAPS feeder lines - terrestrial network gateway, HAPS radio links - satellite retransmitter (SR), etc. The economic efficiency of the proposed solution is assessed.

• Journal of radiological science and technology
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• v.41 no.4
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• pp.297-304
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• 2018

This study proposes measures and methods to reduce healthcare associated infections by comparing and analyzing the bacterial contamination level before and after putting on personal protective equipment (PPE) on the test equipment and the contact infected patients getting chest PA projections. Among the 50 inpatients who were diagnosed with C. difficile, MRSA, and VRE, 28 patients who were instructed to undergo chest PA projection and follow-up were chosen, The 3 parts that come in contact with the detector, chin, chest, and hands, were designated for all, and the bacterial contamination level before and after disinfection and before and after putting PPE was determined. Statistical analysis was performed using Medcalc version 14, and quantitative analysis was performed using paired student t-test, with statistical significance being noted at p<0.05. Results for the comparison of the mean values before and after disinfection of the detector, chin (3.000), chest (2.000), and hands (3.430), showed that the number of bacteria after disinfection was lower than it was before disinfection. Analyzing for each part before and after disinfection, there were statistically significant differences for the chin, chest, and hands (p<0.01). Results for the comparison of the mean values before and after putting on PPE, chin (2.202), chest (2.140), and hands (4.213), showed that the number of bacteria after putting on PPE was lower than it was before putting on PPE. Analyzing for each part before and after putting on PPE, there were statistically significant differences for the chin, chest, and hands (p<0.03). As a result, it was confirmed that the number of bacteria after putting on PPE was lower than it was before putting it on. In the future, expanding the research scope for contact infected patients will establish standards for quarantine guidelines depending on the way it spreads, and contribute to the prevention of healthcare associated infections.