• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.1
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• pp.171-181
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• 2013

The relationship about corporations' dividend policy and foreigners' share have been studied on the various views. However, there have barely been the studies about the relationships between the two variables according to hot and cold markets in Korea. In this point, this study attempts to find the differences of the tendency of foreigners' investment with financial variables and the relationship between foreigners' share and corporations' dividend policy according to hot and cold markets. For the analysis, it selected the 318 manufacturing corporations, which paid dividends in 2008 (cold market) and 2010(hot market). The results are classified into two types. 1) There are the difference, and 2) There are no differences of the relationships among the variables according to the two markets. First of all, The relationships between 1) foreigners' share and dividend 2) between foreigners' share and market value (Tobin's Q) and corporations' debt (Debt Ratio) were statistically significant in the both (hot and cold) markets. As showing the differences according to hot and cold markets, cash flow and foreigners' share showed the statistically significant relationships in 2010 (hot market), not in 2008 (cold market). One of the remarkable results is that most of relationships among variables, except the relationship between foreigners' share and dividend, are more strong in hot market than in cold market.

• The Korean Journal of Malacology
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• v.26 no.2
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• pp.151-156
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• 2010

For industrialization of the hard clams, Meretrix petechiails (Lamarck), spawning was induced per spawning induction technique in the artificial maturation group administered of parent maturation control and the natural maturation group of which parents were transported for artificial spawning per time period. Then, fertilization rates, hatching rates and D-shaped larva development rates were investigated. In addition, growth and survival rates of larvae were investigated per larva breeding technique. The results of spawning induction by exposure in the artificial maturation group indicated that response rates were relatively higher at 23% and 32% respectively at the 4th hour and the 8th hour of exposure. In terms of water temperature increase, responses began only when the temperature reached $28^{\circ}C$ or higher. In the experiment group administered with both exposure and water temperature increase techniques, response rate was found to be 45% or higher at the 4th hour of exposure and the temperature of $28^{\circ}C$. At the temperatures of 29, 30 and $31^{\circ}C$, significant differences were not observed. Therefore, it was indicated that the response rates of parent hard clams were higher toward water temperature increase than exposure time. As for spawning induction per time period of the transported parent group, response rate and D-shaped larva development rate were the highest at 67.6% and 96% respectively on August 6, 2009. In terms of water temperatures during larva breeding experiment, growth was faster as water temperature was higher. In addition, growth and survival rates were relatively higher at the salinity of 25. In terms of stocking density, growth and survival rates were relatively higher at 5 inds./mL.

• Journal of the Korea Convergence Society
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• v.12 no.6
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• pp.9-16
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• 2021

In the past, there have been various studies on predicting the stock market by machine learning techniques using stock price data and financial big data. As stock index ETFs that can be traded through HTS and MTS are created, research on predicting stock indices has recently attracted attention. In this paper, machine learning models for KOSPI's up and down predictions are implemented separately. These models are optimized through a grid search of their control parameters. In addition, a hybrid machine learning model that combines individual models is proposed to improve the precision and increase the ETF trading return. The performance of the predictiion models is evaluated by the accuracy and the precision that determines the ETF trading return. The accuracy and precision of the hybrid up prediction model are 72.1 % and 63.8 %, and those of the down prediction model are 79.8% and 64.3%. The precision of the hybrid down prediction model is improved by at least 14.3 % and at most 20.5 %. The hybrid up and down prediction models show an ETF trading return of 10.49%, and 25.91%, respectively. Trading inverse×2 and leverage ETF can increase the return by 1.5 to 2 times. Further research on a down prediction machine learning model is expected to increase the rate of return.

• Science of Emotion and Sensibility
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• v.1 no.1
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• pp.79-91
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• 1998

이 연구의 목적은 IAPS(국제정저사진체계) 사진자극에 의해 유발된 각각의 주관적 정서상태에 특정적인 자율신경계 반응이 존재하는지를 규명하는 것이다. 부정적 정서(분노, 슬픔, 놀람)와 긍정적 정서(행복, 흥분)를 유발하는 IAPS사진을 각 60초 동안 제시하였을 때 유발되는 심박률, 호흡률, 피부전도반응을 측정하였다. 시각자극이 주어진 초리 30초 동안 통계적으로 유의미한 심박률 감속 및 호흡률 감소를 보여주었으며, 뚜렷한 피부전도반응이 출현하였다. 심박률 감속은 혐오보다 흥분에서 더 크게 나타났고, 피부전도반응의 진폭은 혐오보다 흥분에서 더 큰 것으로 나타났다. 한편, 피부전도반응의 진폭이 상승하는 시간은 슬픔, 행복, 놀람보다 혐오에서 더 짧아지는 경향을 보여주었다. 이와 같은 자율신경계 반응(심박률, 호흡률, 피부전도반응)은 정서상태간에 뚜렷한 차이를 보여주며, 특정 정서상태에서 자율신경계 반응은 개인차가 있기는 하지만 전체적으로 매우 전형적인 반응패턴을 보여주었다. 본 연구의 결과는 정서 특정적인 자율신경계 반응이 존재할 가능성을 시사해주며, 생리신호분석을 통해서 심리적 정서를 결정할 수 있는 형판(template)의 구성을 위해서 다양한 자율신경계 정서반응의 지표를 포괄적으로 측정 분석하는 후속연구가 요구된다.

• The Korean Journal of Financial Management
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• v.17 no.1
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• pp.13-44
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• 2000

본 연구는 1987년부터 1997년까지 11년간을 연구기간으로 하여 이 기간 중에 유상증자를 실시한 기업에 대한 장기(長期) 성과를 조사했다. 연구방법으로는 증자기업과 기업규모, 장부가-시가비율, 수익성에 있어 유사한 비증자기업을 비교기업으로 엄선하여 양 그룹간의 증자 후 3면간의 주가수익률과 영업성과를 비교하는 방법을 택했다. 실증분석 결과 증자기업이 비증자기업에 비해 주가수익률과 영업성과에 있어 모두 열등한 성과를 보이고 있는 것으로 나타났다. 구체적으로 증자 후 3년 동안 증자기업의 보유기간수익률이 비증자기업에 비해 27.7%나 낮았으며, 증자전후 7년 동안의 영업성과에 있어서도 증자기업이 통계적으로 유의한 저성과를 보이고 있는 것으로 나타났다. 또한 유상증자로 재무구조가 개선된다는 증거도 발견할 수 없었다. 이 밖에도 연구는 초과 주가수익률과 초과 영업성과에 대한 시계열적 특징을 조사하였으며, 증자시점에 관해서도 주가가 상승하고 있을 때 유상증자를 실시하는 경향이 있지만 증자전 회계적 이익이 큰 기업이 증자를 실시하는 경향은 없다는 증거를 제시하고 있다.

• The Korean Journal of Financial Studies
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• v.9 no.1
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• pp.69-93
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• 2003

본 연구는 자사주매입에 대한 공시가 기업가치에 어떠한 영향을 미칠것이며 공시일 전후 주가반응이 자사주매입 한도 변경에 따라 시장에서 어떻게 반응할 것인지 그리고 아직 학계에서 다루어지지 않은 미시적인 관점에서 실제 자사주매입 비율에 영향을 미치는 요인이 무엇인지에 관해 실증분석을 실시하였다. 실증분석 결과 자사주매입 공시일 전후 유의적인 양(+)의 비정상초과수익률을 나타내었으며, 한도확대 이후 누적비정상수익률은 유의적으로 증가하였다. 목표매입비율이 클수록 유의적으로 누적비정상수익률은 증가하는 것으로 나타나고 있어 자사주 취득에 대한 저평가 가설을 지지하는 것으로 해석된다. 예기치 않은 현금흐름은 대체로 누적비정상수익률과 양(+)의 유의적인 관계를 보여 예기치 않은 현금흐름이 많은 기업일수록 자사주매입의 정보효과가 크게 나타나 Stephens & Weisbach(1998)의 결과와 일치하였다. 또한, 자사주매입 이후 1개월의 성과를 나타내는 누적비정상수익률은 실제 자사주매입 비율과 유의적인 부(-)의 관계를 보여 공시 이후 주가가 상승할수록 목표대비 실제 자사주매입액은 감소하여 경영자가 공시 이후 주가변화추이에 따라 자사주매입 수량을 조정하고 있는 것으로 파악되었다.

• Journal of the Korean earth science society
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• v.32 no.7
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• pp.719-731
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• 2011

Based on the ICE-3G and ICE-5G ice models, we predicted the velocities of crustal uplift caused by Glacial Isostatic Adjustment (GIA) at 39 tide gauge sites operated by Korea Hydrographic and Oceanographic Administration (KHOA). We also divided the Korean peninsula in the ranges of $32-38.5^{\circ}N$ and $124-132^{\circ}E$ in $0.5^{\circ}{\times}0.5^{\circ}$ grids, and computed the GIA velocities at each grid point. We found that the average uplift rates due to GIA in South Korea were 0.33 and 1.21 mm/yr for ICE-3G and ICE-5G, respectively. Because the GIA rates were relatively high at ~1 mm/yr when the updated ice model ICE-5G was used, we concluded that the GIA effect cannot be neglected when we compute the absolute sea level (ASL) rates around the Korean peninsula. In this study, we corrected the ICE-5G GIA velocities from the relative sea level rates provided by KHOA and we computed the ASL rates at 13 tide gauge stations. As a result, we found that the average ASL velocity around the Korean peninsula was 5.04 mm/yr. However, the ASL rates near Jeju island were abnormally higher than the other areas and the average was 8.84 mm/yr.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.439-445
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• 2009

This study has tries to define the structure of cubical substitute lot development and develope the logical tool for GIS(Geographic Information System). The research has found such important variables as the gap of land price, FARIfloor area ratio), LBR(land burden ratio) and etc. Among those variables, current land price and increasing rate of the price could not be controled by the developer and governments. LBR and FAR, however, could be negotiated and regulated by those shareholders. The result could define the control variables in cubical substitute lot which should be included in the future system for the development tool. The outcome could give the objective ground for local governments, landlords, and engineering companies which involve the cubical subsititute lot.

• Journal of Navigation and Port Research
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• v.37 no.4
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• pp.409-418
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• 2013

On the assumption of the rise of sea level, the inundation vulnerabilities on coastal areas of Korea are evaluated in different ways. The propose of this study is to find out the influences of sea level rise caused by global warming at Young-do coastal area, and to suggest the prevention schemes against the flooding damage caused by the sea level rise. The potential rates of sea level rise are assumed and with these rates the inundation vulnerabilities are simulated using CAD program. With the virtual maps, as the results of the previous CAD simulation, this study attempts to suggest the flood prevention schemes for each sector of damage-expected coastal area.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.5
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• pp.383-388
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• 2021

Air-breathing engines used in aircraft have a performance limit as the altitude increases, and this determines the service and absolute ceiling altitude. The method of maintaining altitude and speed in a fixed-wing aircraft in level flight using classical control method is generally using thrust for speed increase/deceleration and pitch attitude for altitude increase/decrease. If this method is used near the service ceiling altitude, increasing the pitch to reduce the altitude error results in a speed reduction. Therefore, it is necessary to use a control method that maintains the speed first using the pitch attitude. Especially in the case of unmanned aerial vehicles, these two methods should be automatically available at the right time. In this paper, we propose a method of switching the speed and altitude maintenance algorithm near service ceiling altitude.