• Journal of Labour Economics
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• v.24 no.1
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• pp.231-251
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• 2001

In this study I attempted to compare the two contrasting theories on life satisfaction; alsolute or relative. I could confirm a positive curve-linear relationship of income and life satisfaction among Koreans as in many previous studies. A relative hypothesis saying that one's relative superiority on education could bring about more satisfaction was partly supported in this study. On the other hand, another relative hypothesis saying that income increase could make more satisfaction than income decrease over time on a identical level of income was rejected. This result suggests that income increase can not give more satisfaction in addition to more affluence simply because of the fact that one's current income is higher than his or her previous level of income.

• Analytical Science and Technology
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• v.25 no.3
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• pp.164-170
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• 2012

Cyanoacrylate fuming mehod is effective for latent fingerprints developing on non-porous surfaces. In this study, we investigated optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber. The effects of temperature, relative humidity, fuming method and processing time were checked throughly. The amount of evaporated cyanoacrylate was increased at higher temperature, but cyanoacrylate polymerization on the fingerprint ridge was best at $30^{\circ}C$. With a relative humidity of 40% to 50% conditions, good quality of fingerprints were developed. If a relative humidity is lower than 30% or higher than 60%, polymerization rate of cyanoacrylate monomers on the fingerprint ridge was decreased. It was identified that application of $OMEGA-PRINT^{TM}$ dispersal pad or cotton ball with sodium hydroxide fuming method in vacuum chamber was more effective than natural fuming method. We found that cyanoacrylate processing time in vacuum chamber did not have more significant than relative humidity.

• Membrane Journal
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• v.20 no.1
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• pp.76-86
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• 2010

This study investigated the effect of 2-butoxyethanol (BE) as a nonsolvent additive, relative humidity and air contact time on the structure formation of microfiltration membranes, permeation and morphology properties in phase inversion process. The membranes were prepared by using polyethersulfone (PES)/Dimethyl formamide (DMF)/p-toluenesulfonic acid (TSA)/Polyvinylpyrrolidone (PVP)/BE casting solution and water coagulant. Casting solutions containing various concentration of BE were exposed to a water vapor, under 60 and 80% of relative humidity for 40 and 90 sec, which would be absorbed on. The correlations between the membrane permeation properties and surface/inner structures of membrane were investigated. The characterization of membranes was carried out by a capillary flow porometer, a FE-SEM and a water permeation test apparatus. The surface structure of PES membranes was affected by the exposure time as well as the relative humidity strongly. Furthermore, the addition of BE helped control surface and inner structure at certain humidity and exposure time.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.1-11
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• 2013

This study attempt to explore how much characteristics of personal and institutional of staffs in shelter for teenage runaway influence to client's violence, and which factor of them are relative to client's violence. For this aims, we carried out a survey, survey subjects in shelter for teenage runaway participated in this research. T-test and variance analysis attempted to compare degree of violence experience of respondents by personal and institutional characteristics. According to result of analysis, age in the midst of personal characteristics is meaning difference and duty-time and type of shelter in the midst of institutional characteristics revealed meaning difference. Next, Multi-regression analysis tried to explore relative factor influencing on client's violence. The results, age in the midst of personal characteristics is relative with physical violence, duty-year in present institution is relative with etc harm. Also, duty-time per week of institutional characteristics is relative all with four type of violence. Type of shelter is relative with property harm, emotional violence and etc harm. Counseling time during duty is relative with physical violence. Above results provide basic data to find ways preventing client's violence to staffs in shelter for teenage runaway.

• Computers and Concrete
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• v.21 no.5
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• pp.559-567
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• 2018

In this study alkali activation of Electric Arc Furnace Slag (EAFS) is studied with a comprehensive test program. Three different silicate moduli (1-1,5-2), three different sodium concentrations (4%-6%-8%) for each silicate module, two different curing conditions (45%-98% relative humidity) for each sodium concentration, two different curing temperatures ($400^{\circ}C-800^{\circ}C$) for each relative humidity condition and two different curing time (6h-12h) for each curing temperature variables are selected and their effects on compressive strength was evaluated then regression equations using multiple linear regressions methods are fitted. And then to select the best regression models confirm with using the variables, the regression models compared between itself. An Artificial Neural Network (ANN) models that use silicate moduli, sodium concentration, relative humidity, curing temperature and curing time variables, are formed. After the investigation of these ANN models' results, ANN and multiple linear regressions based models are compared with each other. After that, an explicit formula is developed with values of the ANN model. As a result of this study, the fluctuations of data set of the compressive strength were very well reflected using both of the methods, multiple linear regression with quadratic terms and ANN.

• Journal of Drive and Control
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• v.17 no.4
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• pp.8-14
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• 2020

Intelligent devices using ICT technology have been introduced in the field of construction machinery to improve productivity and stability. Among the intelligent devices, Machine Guidance is a device that provides real-time posture, location, and work range to drivers by installing various sensors, controllers, and satellite navigation systems on construction machines. Conversely, the efficiency of equipment that requires location information, such as machine guidance, will be greatly reduced in buildings, and tunnels in the GPS blind spots. Thus, the other high-precision positioning technologies are required in the GPS blind spot zone. In this study, we will develop a relative position measurement system that provides precise location information such as construction machinery and robots in a local area where the GPS reception is difficult. A relative position measurement system tracks a marker in the form of a sphere installed on a vehicle by using the image base tracking technology, and measures the distance and direction information to the marker to calculate a position.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.11
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• pp.995-1004
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• 2011

Object X-ray method commonly used for hole search in overset grids requires huge amount of time due to complicated vector calculations to search the cross-points as well as time-consuming hole search algorithm with respect to background grids. Especially, when the grid system is in motion relative to the background, hole points should be searched at every time step, leading to hung computational burden. To cope with this difficulties, this study presents an efficient hole search algorithm mainly designed to reduce hole searching time. To this end, virtual surface with reduced grid points is suggested and logical operators are employed as a classification algorithm instead of complicated vector calculations. In addition, the searching process is further accelerated by designating hole points in a row rather than discriminating hole points with respect to each background grid points. If there exists a relative motion, the present algorithm requires much less time because only the virtual surface needs to be moved at every time step. The hole searching time has been systematically compared for a few selected geometries.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.197-205
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• 2000

Productivity of container cranes and gantry cranes is influenced by the performance of crane hardware and cycle time. Cycle time in container handling is influenced by the path of containers and relative positioning of containers. So we have to minimize the sway of containers and spreaders to minimize relative positioning time. And sway minimization is influenced by the skill of workers in manual gantry cranes. In this paper, we will survey some anti-sway systems. Each system has some merits and some shortages. And we will show our choice and its experimental equipment which is under construction.

• Journal of Mechanical Science and Technology
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• v.16 no.6
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• pp.770-775
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• 2002

In this paper, a game optimal receding horizon guidance law (GRHG) is proposed, which does not use information of the time-to-go and target maneuvers. It is shown that by adjusting design parameters appropriately, the proposed GRHG is identical to the existing receding horizon guidance law (RHG), which can intercept the target by keeping the relative vertical separation less than the given value, within which the warhead of the missile is detonated, after the appropriately selected time in the presence of arbitrary target maneuvers and initial relative vertical separation rates between the target and missile. Through a simulation study, the performance of the GRHG is illustrated and compared with that of the existing optimal guidance law (OGL).

• Journal of information and communication convergence engineering
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• v.15 no.2
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• pp.123-130
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• 2017

The early detection of intravenous (IV) infiltration is necessary to minimize the injury caused by the infiltration, which is one of the most important tasks for nurses. For detecting early infiltration in patients receiving invasive vein treatment, bioelectrical impedance was measured using multi-frequency bioelectrical impedance. The impedance decreased significantly at infiltration, and then decreased gradually over time after infiltration. The relative impedance at 20 kHz decreased remarkably at infiltration, and then gradually decreased thereafter. In addition, the impedance ratio increased temporarily at infiltration and then gradually decreased over time. Furthermore, the impedance at each frequency decreased quantitatively over time. This indicates that IV solution leaking from the vein due to infiltration accumulates in the subcutaneous tissues. Moreover, slopes of log Z vs. log f differently decreased with increasing log f, indicating that the impedance exhibits different responses depending on the frequency.