• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.218-225
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• 2011

Dual frequency identification sonar (DIDSON) is an imaging sonar that has been used for numerous fisheries investigations in a diverse range of freshwater and marine environments. The main purpose of DIDSON is fish counting, fish sizing, and fish behavioral studies. DIDSON records video-quality data, so processing power for handling the vast amount of data with high speed is a priority. Therefore, a semiautomated analysis of DIDSON data for fish counting, sizing, and fish behavior in Echoview (fisheries acoustic data analysis software) was accomplished using testing data collected on the Rakaia River, New Zealand. Using this data, the methods and algorithms for background noise subtraction, image smoothing, target (fish) detection, and conversion to single targets were precisely illustrated. Verification by visualization identified the resulting targets. As a result, not only fish counts but also fish sizing information such as length, thickness, perimeter, compactness, and orientation were obtained. The alpha-beta fish tracking algorithm was employed to extract the speed, change in depth, and the distributed depth relating to fish behavior. Tail-beat pattern was depicted using the maximum intensity of all beams. This methodology can be used as a template and applied to data from BlueView two-dimensional imaging sonar.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.193-201
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• 2015

The history of Korea Qualification system began after the Korea War. The Qualification was recognized to it's value with economic growth until the 2000. But the value of qualifications has to be re-evaluated under the current global environments. Almost Previous research has not to work for the value of qualifications all of Korea. So, This study presents a evaluation structure frame to work and some evaluation factors for the qualification value. In addition, the methodology proposed to obtain results using the AHP weights based on the evaluation methodology and questionnaire. The analysis results are used as a basis for selecting the future policy direction of the national qualification.

• Journal of Korean Academy of Nursing Administration
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• v.23 no.2
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• pp.191-200
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• 2017

Purpose: This study was conducted to identify the influence of nurse manager and peer group caring behaviors as perceived by nurses on intention to retention. Methods: The participants for this study were 229 nurses who had worked for over 6 months in general hospitals located in J province. Survey data were analyzed descriptive statistics and t-tests, ANOVAs with $Scheff{\acute{e}}^{\prime}s$ post-hoc testing, Pearson's correlation coefficients, and hierarchical regression analysis. Results: The scores for 'manager and peer group caring behaviors' and intention to retention were all at a moderate level, although the subjects perceived 'peer group caring behaviors' as higher compared to 'manager caring behaviors'. There were significant differences in 'manager caring behaviors' scores by suitability for present working department and employment status and in 'peer group caring behaviors' scores by suitability for present working department. The factors influencing nurses' intention to retention were religion, suitability for present department, clinical experience of over ten years, 'manager caring behaviors', and 'peer group caring behaviors' Conclusion: To improve nurses' intention to retention, it may be necessary to alter the transfer and arrangement strategies of their working environments to better consider nurses' aptitude and competence, and thereby increase both manager and peer group caring behaviors.

• Journal of Korean Academy of Nursing
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• v.36 no.5
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• pp.761-769
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• 2006

Purpose: Even though a number of studies have suggested that appropriate measuring instruments of family stress for working women have to be developed, the validity and reliability of the instruments used have not been consistently examined. The purpose of the present study was to develop a sensitive instrument to measure family stress for married working women, and to test the validity and reliability of the instrument. Method: The items generated for this instrument were drawn from a comprehensive literature review Twenty four items were developed through evaluation by 10 experts and twenty one items were finally confirmed through item analysis. Psychometric testing was preformed and confirmed with a convenient sample of 240 women employed in the industrial sector. Result: Four factors evolved by factor analysis, which explained 50.5% of the total variance. The first factor 'Cooperation' explained 28.1%, 2nd factor 'Satisfaction with relationships' 10.6%, 3rd factor 'Democratic and comfortable environment' 6.3%, and 4th factor 'Disturbance of own living' 5.5%, Cronbach's coefficient of this instrument was 0.86. Conclusion: The study supports the validity and reliability of the instrument.

• Journal of Environmental Health Sciences
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• v.40 no.2
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• pp.81-87
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• 2014

Objectives: We measured the concentrations of culturable airborne fungi (CAF) in enclosed environments at 16 underground subway stations of the Seoul Metro in 2013, and investigated the effect of environmental factors, including temperature, relative humidity, the number of passengers, and distance from the platform. Methods: The cultured fungi were identified by the lactophenol cotton blue (LPCB) staining method and were classified by observing the form, shape, and color of colony. A nonparametric analysis was used to determine if the differences in the concentrations of CAF were statistically significant. Results: The concentrations of CAF at the stations were the highest in station p ($367CFU/m^3$) with arange between 3 and $437CFU/m^3$. There was a significant correlation between CAF concentration and the distance from platform (r = 0.544, p < 0.01). Geotrichum spp. and Penicillium spp. were the predominant species. Conclusion: It is recommended that special attention be given during rush hour, which is in the morning (08:00-10:00) and in the early evening (18:00-19:00) to improve the indoor air quality of the subway stations.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.4
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• pp.1-8
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• 2020

Mechanical components that support structures in aerospace and power generation industries require high-strength materials. Particularly, in the aerospace industry, aluminum alloys, titanium alloys, and composite materials are increasingly used due to their high maneuverability and durability to withstand low temperature extreme environments; however, ultra-high-strength steel is still used in key components under heavy loads such as landing gears. In this paper, the fault cause analysis and troubleshooting of aircraft parts made of ultra-high-strength steel (300M) broken during normal operation are described. To identify the cause of the defect, a temporary inspection of the same aircraft was performed, and material testing, non-destructive inspection, microstructure examination, and fracture area inspection of the damaged parts were performed. Fracture analysis results showed that a crack in the shape of a branch developed from the tool mark in the direction of the intergranular strain. Based on the results, the cause of fracture was confirmed to be stress corrosion.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.8
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• pp.69-74
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• 2014

Recently, many countries are researching and developing the various Electric Vehicle(EV) for reserving their natural environments and so on. But the charging time that is longer than the time of filling up the traditional engine vehicle will be the obstacles of spreading them. So, the other type EV is developed. It is the Battery Changeable EV. But there is not testing method for it. Especially, the defining of the durability evaluation for the couplers between battery and charger is very important because the couplers are changed very frequently. So, they may cause many faults and problems. Therefore, this study shows the definition of the durability procedure and the test is conducted with the equipment.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.226-228
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• 2006

In this paper we describe a simulation and development framework for designing mobile 3D graphics architectures. We are developing a simple and flexible simulation and verification environment (SVE) that uses gITrace's ability to intercept and redirect an OpenGL/ES streams. In combination wlth gITrace to trace OpenGL/ES commands, the SVE simulates the behavior of mobile 3D graphics pipeline during playback of traces, and then produces the second geometry trace that can be used as a test vector for the Verilog/HDL RT-level model. By comparing the frame-by-frame results, we can conduct architectural verification. To demonstrate the functionality of the SVE, we show the implementation of the verified mobile 3D architecture on a FPGA board. For this, we also present an application development environment (ADE) includes a mobile graphics API and a device driver interface (DDI). The proposed two software environments, the SVE and the ADE could be used fer developing and testing mobile applications, architectural study and speculative hardware designs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.4
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• pp.1076-1089
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• 2012

Home automation networks are good environments for merging sensor networks and consumer electronics technologies. It is very important to reduce the energy consumption of each sensor node because sensor nodes operate with limited power based on a battery that cannot be easily replaced. One of the primary mechanisms for achieving low energy operation in energy-constrained wireless sensor networks is the duty-cycle operation, but this operation has several problems. For example, unnecessary energy consumption occurs during synchronization between transmission schedules and sleep schedules. In addition, a low duty-cycle usually causes more performance degradation, if the network becomes congested. Therefore, an appropriate control scheme is required to solve these problems. In this paper, we propose UDC (Unsynchronized Duty-cycle Control), which prevents energy waste caused by unnecessary preamble transmission and avoids congestion using duty-cycle adjustment. In addition, the scheme adjusts the starting point of the duty-cycle in order to reduce sleep delay. Our simulation results show that UDC improves the reliability and energy efficiency while reducing the end-to-end delay of the unsynchronized duty-cycled MAC (Media Access Control) protocol in sensor-based home automation networks.

• Journal of the Korean institute of surface engineering
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• v.45 no.6
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• pp.272-277
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• 2012

The hull of a fast sailing aluminium ship are generally prone to erosion owing to the impact of seawater. At this time, synergistic effects of the erosion and the corrosion by aggressive ions such as chlorides tend to aggravate the damage. There have been various attempts, including selection of erosion-resistant materials, cathodic protection and addition of corrosion inhibitors, to overcome damage by erosion or corrosion under marine environments. These approaches, however, have limits on identifying the damage mechanism clearly, because they depend on analogical interpretation by correlating two damage behaviors after the individual studies are assessed. In this research, it was devised a hybrid testing apparatus that integrates electrochemical corrosion test and cavitation test, and thus the erosion-corrosion behavior by cavitation was investigated more reliably. As a result, the slightest damage was observed at the potentials between -1.6 V and -1.5 V. This is considered to be due to a reflection or counterbalancing effect caused by collision of the cavitation cavities and the hydrogen gas formed by activation polarization.