• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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• pp.1626-1635
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• 2006

The purpose of this study was to search for comfortable protective clothing for waste incinerator workers. The experimental protective clothing came in two types: one whose outer side made use of polypropylene film, and the inner side, a non-woven rayon fabric processed with charcoal with a 10% density (CF): and one whose outer side made use of polyolefine and polyamide films, and the inner side, a non-woven polypropylene fabric (NNCF). Experiments were conducted on five healthy adult women whose average age was 21. These experiments were conducted at a climate chamber, in which the temperature and relative humidity were set below $28{\pm}1^{\circ}C\;and\;50{\pm}10%$, respectively. Measured were the rectal temperature, the skin temperature, the sweating rate, the weight loss, the heart rate, the blood pressure, the temperature, and the relative humidity of a microclimate and subjective sensation. These were measured within a period of 60 min, consisting of a 20-min stable period, a 20-min exercise period (walking exercise for 2 miles/hr on a treadmill), and a 20-min recovery period. Through this experiment, the differences between the human body's physiological reactions to CF and NNCF clothing, and the human body's comfort levels when wearing these, were determined.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.1
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• pp.18-24
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• 1987

For the purpose of getting the accuracy of NNSS fix, the continuous observation was performed to search the factors affecting the accuracy of NNSS fix, and then to examine their effects. The observation was made at Lat. $35^{\circ}'||'&'||'<\TEX>05'04"N, Long. '||'&'||'129^{\circ}'||'&'||'<\TEX> 02'13"E from 28th January to 20th July in 1985. Accuracy of the position fixed in accordance with the observation time, each satellite, elevation angle doppler count, passed direction of each satellite and the antenna height were analyzed. The results obtaines are summerized as follows: 1. The deflaetion error is reduced to 0.21 miles when the geodetic system of the calculating the position converted from WGS-72 to Bessel. 2. When the elevation angle of the mountain is high, or the range of the elevation angle of satellite is 20-70 degrees, the position fixed comes nearest the true position. 3. The position fixed is more accurate on the condition that doppler count is more than 21, and at night than in daytime. 4. The accuracy of the position fixed is more seriously affected when the input data of the antenna height has considerable errors. But there occures almost little difference in the accuracy of position according to each satellite.

• Journal of the Korean Applied Science and Technology
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• v.22 no.1
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• pp.15-20
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• 2005

$Na_2CO_3$. Sodium orthosilicate (Na-OSi), Tetronix T-701 (T-701), Na-dioctyl sulfosuccinate (303C), Newpol PE-68 (PE-68), MJU-100A, and tetrasodium pyrophosphate were blended to prepare high performance alkaline cleaning agents (ACASs). The results of cleaning test with steel specimen showed that ACAS-6 ($Na_2CO_3$ 50g/Na-OSi 35g/T-701 20g/303C 18g/PE-68 17g/MJU-100A 10g/TSPP 20g/ water 180g mixture) had a good cleaning power. The cleaning power for press-rust preventing oil was 98% and 99% degreasing at 4wt%, $70^{\circ}C$ and $90^{\circ}C$, respectively ; for quenching oil, the cleaning power of ACAS-6 was 91% degreasing at 4wt% and $70^{\circ}C$. The foam heights measured immediately after foaming by Ross & Miles method and Ross & Clark method at 6wt%, $60^{\circ}C$ were 18mm and 65mm, respectively. It was concluded that ACAS-6 had a good low foaming cleaning agent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.316-329
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• 1983

The formation and structure of the shelf front in the eastern part of the Yellow Sea are studied on the basis of oceanographic data collected in August, 1982 and February, 1983. This paper also describes the distribution of planktonic organisms of the shelf front. In summer the shelf front is formed in the area ($126^{\circ}02^'E-126^{\circ}05^'E$) ca. 20 miles from the shore at the depths of 15-25 m. in winter, however, no distinct shelf front is formed. Based on the cluster analysis of surface phytoplankton the species composition shaws a discontinuous pattern in the vicinity of the shelf front in summer, 1982. A similar trend is observed in distribution of some copepod species in winter, l983.

• Journal of the Korean Society of Marine Environment & Safety
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• v.6 no.2
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• pp.1-15
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• 2000

In world trade, the vessel traffic in major routes has been congested due to the rapid increase of cargoes and shipping tonnages. The patterns of vessel traffic have also been complicated and diversified. Therefore it was necessary that the Vessel Traffic Service(VTS) should be established in order to enhance the safety of navigation, to prevent the loss of life and damage to the environment. The first advanced radar surveillance system(LevelIII-VTS) was introduced in Pohang, Korea in 1993 and in 13 other ports later. While the hardware of Korea VTS is equal to that of an advanced country, the software, specially the operation manual, the recruitment and education of VTS operator, and the VTS service area is behind that of Russia, USA, Germany, Hong Kong, Singapore and others. After researching and investigating. the VTS equipment and service area of many countries, and analyzing the IMO regulations relevant to VTS and the traffic pattern and accident of Pohang port, the most efficient VTS service area should be established in Pohang. According to the analysis of the preceding studies and research on VTS, the worldwide VTS areas are recognized under the following conditions: First, the service area should be extended over at least radar coverage taking into account of traffic flow, traffic density, the degree of danger to navigation and harbour condition in order to provide all possible services. Second, the established service area should be subdivided and systematized to render reliable VTS services, such as the allocation of VHF frequency and reporting procedure in each area. In conclusion, the VTS service area of Pohang must be established and operated over 10 miles from shore(radar site) covering the radar coverage, so as to include the area of traffic congestion and high density traffic flow.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.827-832
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• 2004

Up to now a lot of the study on ship collision avoidance systems have proceeded actively. However the rate of ship collision accidents hasn't decreased yet. If there is collision risk in close quarters situation in spite of maneuvering ship for collision avoidance according to the system, only use of TCP A and DCP A as input factor for collision risk decision is not useful to avoiding collision action. For the recent 5 years by the analysis of first observation distance about approaching ship in domestic collision accidents, nearly $45\%$ of accidents is close first observation less than 2 miles. Therefore it is essential part for safety navigations to study for collision avoidance action in close encounter. In this paper, as a fundamental study of supporting collision avoidance maneuvering for navigators, we proposed ship collision avoidance support model in close quarters situation through analysis qf collision accidents to effectively get rid of the causes.

• Journal of Advanced Navigation Technology
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• v.16 no.4
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• pp.578-585
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• 2012

CNS/ATM(Communication Navigation Surveillance/Air Traffic Management) was adopted as a standard navigation system of 21st century. Therefore, ICAO(International Civil Aviation Organization) members are developing the technology and infrastructure of CNS/ATM. ADS-B(Automatic Dependent Surveillance-Broadcast) system and Multilateration system are being implemented in the surveillance field of CNS/ATM. Multilateration system is installed in order to complement radar system and to surveil blind areas. Also, Multilateration system using TDOA(Time Difference Of Arrival) is more accurate than radar. In this paper, we applied an IMM(Interacting Multiple Model) filter which is widely used in radar systems to the Multilateration data in order to improve the reliability of the Multilateration data. Comparisons with the original Multilateration data and the Multilateration data with the IMM filter show that the ADS-B data with the IMM filter provides a better performance: 38.37% near the airport, 20.86% around 10 miles of the airport.

• Transactions on Electrical and Electronic Materials
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• v.17 no.2
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• pp.57-68
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• 2016

In this study, we present the modern hybrid system based power generation for electric vehicle applications. We describe the hybrid structure of modified current source based DC - DC converters used to extract the maximum power from Photovoltaic (PV) and Fuel Cell system. Due to reduced dc-link capacitor requirement and higher reliability, the current source inverters (CSI) better compared to the voltage source based inverter. The novel control strategy includes Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic (PV) and fuel cell power generation system. The proposed DC - DC converters have been analyzed in both buck and boost mode of operation under duty cycle 0.5>d, 0.5<d<1 and 0.5<d for capable electric vehicle applications. The proposed topology benefits include one common DC-AC inverter that interposes the generated power to supply the charge for the sharing of load in a system of hybrid supply with photovoltaic panels and fuel cell PEM. An improved control of Direct Torque and Flux Control (DTFC) based induction motor fed by current source converters for electric vehicle.In order to achieve better performance in terms of speed, power and miles per gallon for the expert, to accepting high regenerative braking current as well as persistent high dynamics driving performance is required. A simulation model for the hybrid power generation system based electric vehicle has been developed by using MATLAB/Simulink. The Direct Torque and Flux Control (DTFC) is planned using Xilinx ISE software tool in addition to a Modelsim 6.3 software tool that is used for simulation purposes. The FPGA based pulse generation is used to control the induction motor for electric vehicle applications. FPGA has been implemented, in order to verify the minimal error between the simulation results of MATLAB/Simulink and experimental results.

• Tribology and Lubricants
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• v.26 no.6
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• pp.317-321
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• 2010

Thin films of tin sulphide (SnS) have been formed by a novel 2-stage process where-in D.C. magnetron sputtering was used to deposit to thin films of tin (Sn) and the layers then sulphidised using 5% hydrogen sulphide ($H_2S$) gas in Argon. Although it was not found possible to deposit high quality thin films of tin directly onto glass substrates, excellent layers of tin were produced by using molybdenum (Mo) coated glass as the substrate material. The chemical and physical properties of the SnS layers formed were determined using scanning electron microscopy, energy dispersive x-ray analysis, x-ray diffraction studies and using reflectance versus wavelength measurements and these related to the conditions of synthesis. The data shows that it should be possible to produce conventional "substrate structure" devices based on the use of this technology.

• Child Health Nursing Research
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• v.8 no.1
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• pp.97-109
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• 2002

This study was conducted to understand the degree and contents of stress which the mothers of high-risk infants can be experienced from the hospitalization of ICU for their new borns, and thus to offer the basic program to he nursing intervention program for these. Subjects were the 171 mother of hospitalized newborn in NICU of 1 University Hospital in Busan from June, 20, 2001 to September, 15, 2001, who agreed to take part in this study. The instruments used in this study were Parental Stressor Scale:NICU(PSS:NICU) developed by Miles et al. The questionnaire has 4 dimensions and 45 items ; sight and sounds of NICU(5 items), babies' appearance and behavior nursing intervention(19 items), parental role alteration and relationship with their baby(10 items), health team communication(11 items). The data was analysed as average, frequency, Standard Deviation, t-test, ANOVA, Pearson correlation coefficient by use of SPSS/PC+. The results of this study are as follows ; 1. The total perceived stress level score of mothers of high-risk infants was slightly high(3.44±0.71). The highest scored dimension was 'appearance and behavior of the baby'(4.06±0.80), and next were 'relationship with their baby and parental role change'(3.55±0.98), 'sight and sounds of NICU'(3.22±1.01), 'communication with health team'(2.93±0.91). 2. The total perceived stress level score was significantly correlated with birth weight (F=2.35, p<.05). 3. In sight and sounds of NICU, the perceived stress level score was significantly correlated with nursing in the incubator(t=2.28, p<.05) and birth weight(t=2.26, p<.05). In summary, information about physical environment of NICU, birth weight and nursing in the incubator must be included in nursing intervention program of mother's of high-risk infants in reducing the patents stress level. And, it is suggested that there need to find the coping mechanism of mother of high-risk infants.