• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1201-1206
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• 2009

According to a lot of investigations, distance perception is influenced by many important cues such as sound pressure level, reflections from the room surface, binaural difference (ITD and ILD), a kind of sound source, and head related transfer functions (HRTF). Two psychoacoustical experiments on auditory distance perception were conducted to examine the effectiveness of the sound pressure level loudness as one of the physical cues in the auditory distance perception under a constant loudspeaker's output level and a constant sound level at the subject's position in the absence of reflections in an anechoic room. Our experimental results showed that the perceived distance of sound image is closer than actual sound source distance with the constant loudspeaker's output level and the constant sound level. Futhermore, the perceived distance of a sound image with constant sound level increased when the actual distance increases up to approximately 2 m while the perceived distance saturated when the sound source distance exceed 2 m. On the other hand, when the condition of loudspeaker's output level was kept constantly, the perceived distance of sound image increased up to around 3m, longer than the conditions of constant sound level at the subject's position. We found that the change in the loudness as a function of distance plays an important role in the auditory distance perception in the absence of reflections..

• Journal of the Korean Geotechnical Society
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• v.31 no.8
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• pp.5-15
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• 2015

One-dimensional rainfall laboratory tests using gneissic weathered soil were conducted to investigate effect of antecedent rainfall on infiltration characteristics. Experimental results using samples from Chuncheon and Chungju sites showed that rainfall onto the ground surface decreased initial negative pore water pressure of unsaturated soils, which recovered gradually after the end of rainfall. Rainfall intensity increases water infiltration rate, and infiltration rate during main rainfall is faster than that of the preceding rainfall. It is considered that higher water saturation after antecedent rainfall increases water infiltration rate during main rainfall. In particular, Chungju sample with higher clay content had slower recovery of negative pore water pressure and infiltration rate. Numerical results using finite element slope stability analysis showed that reduction of initial negative pore pressure due to rainfall infiltration deteriorates slope stability, and diffusion of pore water pressure after the end of rainfall further reduces FS of the slope in the short term. Main rainfall after prior rainfall further reduced factor of safety of the unsaturated slope. Pattern of antecedent rainfall has a significant impact on the magnitude and distribution of initial pore water pressure in unsaturated soils which are controlling factor to assess factor of safety of unsaturated slope during rainfall.

• Environmental and Resource Economics Review
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• v.27 no.3
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• pp.421-461
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• 2018

Windpower turbines have positive values for visitors with regard to tourism and learning. On the other hand, it is clear that windpower turbines have negative impact on the landscape, particularly when the level of landscape is high. The impact of windpower turbines on the visitor's value is composed of two elements: the viewingvalue which is independent of the level of landscape and the landscape value which varies with the level of landscape. The net visitor's value of windpower turbines is the sum of these two values with opposite signs. This study used a choice experimentation method to value the impact of windpower turbine construction in the mountainous area in Korea. This study estimated the viewing value, the landscape value and the visit value as the sum of the two values. The estimated results demonstrated a significantly positive viewing value, a significantly negative landscape value, and weakly negative net visit value in average.

• The Korean Journal of Financial Studies
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• v.8 no.1
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• pp.157-188
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• 2002

본 연구는 우리나라 IPO시장에서 나타나고 있는 초과수익률의 원인을 밝히고자 최근 벤처금융의 중심으로 급부상하고 있는 KOSDAQ시장의 공모 IPO를 대상으로 실증분석을 시도하였다. 연구결과 상장일 표본전체 IPO의 초과수익률(AR1)이 9.91%로 나타났으며, 벤처캐피탈투자 IPO는 5.13%, 비투자 IPO는 13.29%로 나타났다. 상한가의 행진이 종료된 날을 기준으로 한 표본전체 IPO의 초과수익률(AR2)은 30.97%, 벤처캐피탈 투자기업 IPO는 24.34%, 비투자기업 IPO는 34.67%로 나타났다. 초과수익률의 원인을 분석하기 위한 8개의 변수 중 IPO의 수요증감 척도인 KOSDAQ 지수는 초과수익률(AR)과는 양(+)의 관계로, 벤처캐피탈리스트들의 능력 및 가치책정의 행태를 엿볼 수 있는 변수인 본질가치와 공모가액의 차이는 음(-)의 관계로, 사업규모나 자본조달의 크기를 엿볼 수 있는 공모금액의 크기는 양(+)의 관계로 1% 유의수준에서 유의한 것으로 나타났다. 그러나 여타 변수들은 통계적으로 유의성을 확보하지는 못하였으나 초과수익률의 원인이론으로 '신호이론'과 '투기적 거품가설'에 의한 설명이 가능하였으며 분석결과를 다음과 같이 정리할 수 있었다. 첫째, IPO 본질가치에 대한 신뢰와 IPO의 발행규모에 대한 신뢰수준이 통계적으로 유의한 결과로 나타났는바 이러한 결과는 기업가치와 벤처 또는 사업의 계속적 수행 등에 대한 신호역할을 수행하고 있다고 할 수 있으며 상장초기 초과수익률은 주로 이러한 신호역할에 의한 수요집중으로 발생된 결과인 것으로 사료되었다. 둘째, 노련한 벤처캐피탈회사로 선정된 KTB의 투자기업들은 상장 후 4주간의 거래에 있어 AR 평균이 음(-)으로 여타 벤처캐피탈이 투자된 기업보다 손실 폭이 더욱 켰음에도 불구하고 상장일 초과수익률 AR2가 매우 높게 나타나 우리나라 IPO시장에 있어 과민반응(fads) 현상이 존재하고 있는 것으로 분석되었다. 셋째, 벤처캐피탈 투자 IPO의 초과수익률이 상대적으로 낮아 벤처캐피탈 투자여부가 IPO의 저가발행 수준을 축소하고 있어 벤처캐피탈리스트의 제 3자 보증역할이 어느 정도는 수행되고 있는 것으로 분석되었다.

• Journal of Labour Economics
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• v.30 no.2
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• pp.119-148
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• 2007

Foreign outsourcing, otherwise known as off-shoring, has become a matter of intense public debate and great concern in both developed countries and developing countries. Yet, there is a lack of good data on foreign outsourcing since the early 1990's. This paper presents updated measures of foreign outsourcing for the recent period. Its main findings are that the share of foreign-sourced goods in total manufactured inputs almost doubled-from 12.4 percent to 22.7 percent between 1987 and 2003. I then look at the relationship between the measure of foreign outsourcing activity and wages in US manufacturing industries in recent years from 1998 to 2003. The results show that for all workers, the outsourcing level is statistically significantly and negatively associated with industry wage premiums. The estimate suggests that a magnitude of 0.9 - a 9% decrease in industry wage premiums tends to accompany a 10% increase in industry outsourcing level. Outsourcing has a bigger effect on the less-skilled workers-industry outsourcing level increases by 10% and industry wage premiums decrease by about 11% in the case of less-skilled workers.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.11
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• pp.2512-2520
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• 2013

In this paper, the T-SRR (Triple Split Ring Resonator) using MNG (mu-Negative) meta-material adapted in a low-loss bandpass filter with 3-stages is suggested. The size of the T-SRR in the proposed bandpass filter with low dielectric constant PCB can be easily controlled. And the ${\lambda}/4$ transmission line theory is applied. The proposed T-SRR and filter have the center frequency of 10 GHz with QL value of 184 for military-satellite communication system in I band. The experimental results of the filter show that the insertion and return losses are 1.44 dB and 17.3 dB with bandwidth of 10 %, respectively. The proposed filter will be redesigned by IPD material etc. should be placed here. These instructions give you guidelines for preparing papers for JICCE.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.4
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• pp.91-103
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• 2016

The work zone traffic management is of keen interest because the unstable traffic stream in work zones leads to not only less productive traffic operational efficiency but also negative impacts on traffic safety. A promising method to address such issues is variable speed limit systems(VSLS). VSLS is expected to increase in throughput and to enhance safety by diminishing the crash potential. In addition, the usefulness of VSLS has been demonstrated by significant amount of existing literature. The objective of this study is to identify the effectiveness of VSLS based on a meta analysis technique. Throughput and travel speed were used as measures of effectiveness for VSLS in terms of the operational efficiency and safety respectively. Results showed that approximately 16.4% increase in throughput and 16.5% decrease in travel speed were obtainable by VSLS. The outcomes of this study would be useful in developing technologies and polices for better operation of VSLS.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.200-206
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• 2017

The damage and fragmentation of habitat due to urbanization pose a great threat to amphibians worldwide. To understand the effect of urbanization on the distribution and abundance of Hyla japonica, we measured their population sizes by listening frog calling and investigated the habitat their population sizes and land use in the 18 rice paddy fields located in Incheon and its surroundings. Abundance of H. japonica was 0 - 17 male adults / habitat or 0 - 41 male adults / ha in Incheon. The number of the frog was increased as the distance between the habitat and the road became longer or the ratio of circumstance / area of the habitat increased. Unlike the general prediction, the density of H. japonica showed a negative correlation with the size of the habitat and a positive correlation with the surrounding land use intensity. Our results suggested that H. japonica could be concentrated in a narrow habitat due to the habitat size decrease and the periphery development according to the urbanizaion.

• Polymer(Korea)
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• v.28 no.6
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• pp.460-467
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• 2004

The polymer blends of waste poly(vinyl chloride) (RPVC) and waste polyethylene (RPE) were prepared by melt mixing. Their morphologies and rheological properties were investigated and torque changes were also measured. Comparing the torques calculated by the log additivity rule with measured torque changes, the polymer blends showed the large negative deviation behavior (NDB) due to their incompatibility. The shear viscosities of the blends decreased with increasing shear rates, showing shear thinning behavior. The shear viscosity of the blends with compatibilizer was larger than that of the blends without compatibilizer. SEM micrographs of the strands after measurement showed that the domain size of the blends was slightly enlarged with increasing the shear rate. Also, RPVC domain size was larger in the core-sections of the strands from capillary viscometer than in the surface region.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.585-592
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• 2022

The purpose of this paper is to examine the relation between executive excesss compensation and credit rating. According to the prior research which show the negative effects of excess compensation on a firm's future performance, this paper expects the negative effect of excess compensation on credit rating. Using a sample of Korean listed non-financial firms from 2014 to 2019, I perform the multivariate regressions analysis of excess compensation on credit rating. I find that excess compensation is negatively related to credit rating when executive compensation exceed expected executive compensation. Moreover, I find that the result is constant when a fim belongs to small-medium business. These results show that credit rating is affected by executive excess compensation and the relation could be different by the type of firm's size. Therefore, this study contributes to the literature by suggesting the possibility that capital market is aware of negative effect of executive excess compensation.