• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.23-30
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• 2008

Air sparging technique has been used for remediation of VOC(volatile organic compound)-contaminated aquifer. The aim of this study was to develop an innovative air sparging technique that enhances the efficiency of air intrusion into a specific horizontal layer of aquifer where the contaminants exist with the help of water-soluble surfactant. A twodimensional physical box model, packed with homogeneous sand, was used for simulating the aquifer in this study. Aqueous solution of anionic surfactant (100 mg/L, sodium dodecylbenzene sulfonate) was used to suppress the surface tension of groundwater. Three sets of experiments were conducted: air sparging experiment without surfactant application, air sparging experiments for box model where the surfactant solution was applied right above the air injection point, and air sparging experiments with surfactant solution layer formed in the middle of the box. It was found that the sparging influence zone was expanded up to five times of that formed by sparging without surfactant application. The size of sparging influence zone was more sensitive to the air flow (injection) rate with surfactant application than that without surfactant. More importantly, injection of air into the target aquifer layer was successful with surfactant application. Findings in this study are expected to provide more options for designing remediation processes using air sparging.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.151-156
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• 2003

The vergence control method is presented for a parallel-axls stereo camera (PASC) using a signal processing technique such as shift, (rotation), and scaling. The PASC is considered as the simplest one of binocular stereo cameras. However, its major limitation lies in the controllability of vergence since its left and right imaging sensors of CCDs are fixed. On the other hand, a horizontal-moving-axis stereo camera (HMASC) with movable imaging sensors is able to control the vergence by moving its CCDs horizontally. In spite of its vergence controllability, there is a major drawback in the implementation because of complicated mechanical structure and the additional cost. To overcome the vergence control problem of the PASC, an operational principle of the HMASC is applied to the PASC. To be specific, without any additional hardware the vergence control problem of the PASC is solved with the signal processing technique. Assuming the virtual displacement between CCD's, a disappearing part of acquired images is removed and the original image site is recovered via interpolation. Experimental results show that the vergence control between stereo images captured by the PASC it possible with an acceptable degradation of the image quality defending on the virtual displacement of CCDs.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.1
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• pp.29-38
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• 2016

The purpose of this study is to review the relationship between transformational leadership(charisma, individual consideration, intellectual stimulation, inspiration) and knowledge management, and the moderating effect of social(trust and interaction) in small business. In order to verify and achieve the purposes mentioned above, questionnaire data are gathered and analysed from 311 subjects in Kangwon-do province. Multiple regression and multiple hierarchical regression analysis were applied to test these hypotheses: 1) the relationship between transformational leadership and knowledge management, 2) the moderating effect of trust on the relationship between transformational leadership and knowledge management, 3) the moderating effect of interaction on the relationship between transformational leadership and knowledge management. Empirical survey's findings are as follows; First, individual consideration and inspiration leadership appeared to be positively related with all knowledge management(knowledge creation, transfer, application). Second, charisma was verified to be positively related with knowledge creation only. Third, charisma and inspirational leaderships were more positively with knowledge creation in higher trust group than in lower trust group. Fourth, intellectual stimulation and inspirational leaderships were more positively with knowledge creation in higher interaction group than in lower interaction group. Fifth, individual consideration was more positively with knowledge application in higher interaction group than in lower interaction group.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.167-175
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• 2015

The purpose of this study is to review the relationship between managerial system(CEO support, pay system, education & training) and knowledge management, and the moderating effect of decentralization and formalization in small business. In order to verify and achieve the purposes mentioned above, questionnaire data are gathered and analysed from 227 subjects in Kangwon-do province. Multiple regression and multiple hierarchical regression analysis were applied to test the proposed hypotheses: 1) the relationship between managerial system and knowledge acquisition, 2) the relationship between managerial system and knowledge transfer, 3) the moderating effects of decentralization on the relationship between managerial system and knowledge management, 4) the moderating effects of formalization on the relationship between managerial system and knowledge management. Empirical survey's findings are as follows; First, knowledge acquisition and transfer appeared to be positively related with CEO support and education & training. Second, education & training was verified to be more positively related with knowledge transfer in higher decentralization group than in lower group. Third, CEO support and education & training were more positively with knowledge acquisition in lower formalization group than in higher group. Fourth, pay system were more positively with knowledge transfer in lower formalization group than in higher group.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.12
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• pp.1308-1315
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• 2009

A full-polarimetric scatterometer(HPS: Hongik Polarimetric Scatterometer) for X-band is designed, fabricated, and verified using the theoretically well-known point-targets in this paper. The X-band full-polarimetric scatterometer consists of an OMT(Orthogonal-Mode Transducer)+horn antenna, the angle control part for the OMT+horn antenna, a transmitter/receiver with a network analyzer and a frequency-conversion circuitry, and a movable support of these parts. We use an inclinometer sensor to control the vertical and horizontal incidence angles. The full polarimetric data can be obtained because of the polarization switches and the OMT. The accuracy of the scatterometer system is verified by measuring the polarimetric RCS(Radar Cross Section) of one of the theoretically well-known point-targets, i.e., a corner reflector.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.147-154
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• 2000

To describe the prevalence of binocular anomalies in adult Koreans. Patients included were 19 to 40 years of age, 41 males and 60 females and living in Kwang-Ju Korea. Refractive correction was estimated objectively with an autorefractometer and subjectively refined without cycloplegia. Myopia was defined as a refractive error less than -0.50 diopters hyperopia was defined as a refractive error greater than +0.50 diopters. 101 no strabismic patients who had a refractive error and a near lateral phoria(46%) and an AC/A(accommodative convergence/accommodation) anomaly(50.4%). The prevalence of a near vergence anomaly(52.5%) was higher than a near divergence anomaly(55.5%). The prevalence of a positive relative accommodation(PRA) anomaly(61.4%) was higher than a negative relative accommodation(NRA) anomaly(54.5%). According to Morgan's analysis method, patients with vergence anomaly(21.7%) were seen slightly less frequently than those with accommodative interaction anomaly(29.7%). 34.6% of patients had both vergence anomaly and accommodative interaction anomaly. These results indicate that full prescription for a refractive corrections should be considered as these can improve binocular visual function for ametropia.

• Journal of Bio-Environment Control
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• v.9 no.1
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• pp.27-39
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• 2000

In this study, we quantitatively compare the cooling effects of single span plastic greenhouses by opening or shutting of toot and side vents, and operation of fan or sprinkler. With those variables, we simultaneously made experiments at 4 greenhouses under equivalent conditions. By the experiments, the shutting of roof and side vents caused the high temperature difference of indoor and outdoor which the crops cannot be cultivated. However, the opening of the windows effectively reduced the indoor temperature and showed uniform temperature distribution in the greenhouses. The sprinkler abruptly reduced the indoor temperature, and showed excellent cooling effects. Finally, this paper provides the fundamental data for environmental control in greenhouses.

• Journal of the Korea Society of Computer and Information
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• v.15 no.7
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• pp.67-74
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• 2010

TIn this paper, it is designed the polarization selective antenna for UHF RFID system. The proposed antenna is consist of microstrip patch antenna with dual feeding and two SPDT switches and a SP4T switch and 3dB hybrid coupler. Through control of voltage of switches, the proposed reader antenna can select horizontally linear polarization, vertically linear polarization, left-hand circular polarization (LHCP) and right hand circular polarization (RHCP). The proposed reader antenna satisfied 2:1 VSWR at 902MHz~928MHz. and it has under 3dB AR(axial ratio). Peak gain of antenna is 7.71dBi, 7.55dBi with linear polarization and 7.31dBic, 7.81dBic with circular polarization at x-y plane. Also Axial ratio of antenna is 2.01~2.83dB and 2.02~2.60dB respectively. It is satisfied 3dB axial ratio.

• Journal of Wetlands Research
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• v.11 no.1
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• pp.105-113
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• 2009

Heat energy exchange is very important processes in the coastal wetland ecosystems. We observed and analyzed the net radiation flux, the sensible heat flux, the latent heat flux and the soil heat flux, which are balanced in the heat energy balance, over a reclaimed land covered with reeds at Goheung, Jeonllanamdo where is horizontally plane. The atmospheric turbulence had been measured in order to estimate the heat transfer during 5 intensive observation periods (IOPs). It was considered that the soil consists of water, fine particles, and vegetation canopy that changes color and density according to the season. We examined the characteristics of the heat flux and the vegetation effect on the air temperature control. It was noted that the heat was transported mainly by latent heat flux in the summer season and the vegetation canopy decreased the daily temperature range due to the heat storage. The air temperature was lower at the IOPs site than near urban area. This showed that the coastal wetland covered with the vegetation control the thermal environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1512-1518
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• 2013

Polycarbonates (PCs) with six different end capping agents were synthesized from melt polymerization. Chemical structure of the synthesized PC was determined by FT-IR spectroscopy. The average molecular weight and distribution, glass transition and thermal degradation temperatures were determined by GPC, DSC and TGA. Average molecular weight changed with the chemical structure of end capping agent, and 4-tert-butylphenol was estimated as the optimum end capping agent. The average molecular weights of PCs decreased with the concentration of the agent, the number average molecular weight was observed as 20,000 - 30,000 when 0.05-0.15 mol% of 4-tert-butylphenol added in PCs. The melt viscosities and glass transition temperature of the PCs decreased with molecular weight. The change for adding method of the agent affected on both the molecular weight distribution and decrease in power law index.