• Korean journal of applied entomology
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• v.32 no.1
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• pp.76-82
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• 1993

Phonotaxis of the African mole cricket, Gryllotalpa africana palisot de Beauvois, was investigated in 1990 and 1992 at the agronomy Experiment Station of Korea Ginseng & Tobacco Research Institute in Hwaseong-gun, Kyonggi-do, Male adults produced calling sounds (calling songs) through the openings of subsurface burrows. Intensities of the sound were 77-80 dB at 15 cm above the openings. When tape recordings of male calling songs were broadcasted outdoors at 105-110 dB by two horn speakers installed at the center of a 1.4 m diameter-funnel, flying adults were attracted for 1.5 hours from about 30 minutes after sunset. Among attracted adults, 14.3-16.9% landed in the funnel, and 65.7-74.7% landed on the ground within 2m form the sound source. Females were 66.7-74.3%, which seemed to be due to the sex ratio of the population in the field. Adults landing in the funnel and at the distance of within 2m from the center of the funnel were tend to be a little more than those attracted to a blacklight trap.

• The Journal of the Acoustical Society of Korea
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• v.37 no.5
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• pp.276-283
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• 2018

The purpose of the study is to identify a sound generating organ that has a major influence on the central frequency of the cicadas with the Helmholtz resonator structure for the first time. The sound of cicadas Cryptotympana atrata and Hyalessa fuscata were recorded and analyzed, then the motion of the tymbals was analyzed with a high-speed camera to compare the relationship between the frequency of sound and the motion of the tymbals. As a result, there was little difference in the frequency distribution of calling song and scream for two species. The tymbals of C. atrata oscillated in three vibration modes, while those of H. fuscata oscillated in one mode. There was no difference in the frequency of both tymbals of both cicadas, and three vibration modes of C. atrata generated sound with different frequency bands. The frequency band of tymbals and the central frequency band of calling song were very similar. In conclusion, it is presumed that the frequency of the cicadas with the Helmholtz resonator structure was determined by mode frequency of the tymbals than resonance condition of the abdomen.

• Management & Information Systems Review
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• v.37 no.2
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• pp.187-207
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• 2018

This study examines the negative relationship between accounting conservatism and excess executive compensation and examines whether their relationship increases as managerial incentive compensation intensity increases. For this purpose, a total of 2,755 company-years were selected for the analysis of the companies listed on the Korea Stock Exchange from December 2012 to 2016 as the final sample. The results of this study are as follows. First, there is a statistically significant negative relationship between accounting conservatism and manager overpayment. This implies that managers' incentives to distort future cash flow estimates by over booking assets or accounting profits in order to maximize their compensation when manager compensation is linked to firm performance. In this sense, accounting conservatism can reduce opportunistic behavior by restricting managerial accounting choices, which can be interpreted as a reduction in overpayment to managers. Second, we found that the relationship between accounting conservatism and excess executive compensation increases with the incentive compensation for accounting performance. The higher the managerial incentive compensation intensity of accounting performance is, the more likely it is that the manager has the incentive to make earnings adjustments. Therefore, the high level of incentive compensation for accounting performance means that the ex post settling up problem due to over-compensation can become serious. In this case, the higher the managerial incentive compensation intensity for accounting performance, the greater the role and utility of conservatism in manager compensation contracts. This study is based on the fact that it presents empirical evidence on the usefulness of accounting conservatism in managerial compensation contracts theoretically presented by Watts (2003) and the additional basis that conservatism can be used as a useful tool for investment decision.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.356-367
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• 2000

The purpose of this study was to identify the underlying dimensions of push and pull motivators for Soraksan, Kayasan, Naejangsan, and Pukhansan national parks in mountain regions. This study also examined the nature and extent of the reciprocal relationship between the push and pull factors. The result showed that four dimensions were derived from 12 push items, which were cultural and natural experience, escape and rest, health, and socialization and novelty motivators. Three dimensions also were derived from 12 pull items, which were facilities and culture, nature, and accessibility. The push and pull dimensions were correlated and regressed against each other. Given the nature of relationship between the push and pull factors, facilities and culture pull factor was affected by the cultural and natural experience motivation. Nature pull factor had strongly associated with culture and nature, escape and rest, health, and socialization and novelty motivations. Finally, accessible attraction pull factor had a positive relationship with health motivator, however, had a negative with cultural and natural experiencing motivation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.4
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• pp.271-277
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• 2002

This paper was described on the characteristics of bottlenose dolphin (Tursiops truncatus) whistle to develop a warning and attracting acoustic system which can be made friends woith environment and minimized to the fishing pollution from Cetaceans. The experiment for the acoustics of bottlenose dolphin whistle was carried out in dolphin performance hall at Seoul Grand Park during 18th~19th April, 2002. The frequency and the spectrum level of whistle a same pool were revealed 6~10KHz and 85㏈ but those revealed two harmonic waves a 6.7KHz and 21.3KHz for the frequency and 110㏈ and 94㏈ for the spectrum level, respectively, when a dolphin isolated from others. The range of frequency change of whistle was 3.86KHz and continuous time was 0.08 sec. The range of frequency change 10.20 KHz higher as 14.06 KHz and continuous time was 0.11sec longer as 0.19sec when a dolphin isolated from others. By the Mann-Whitney test for the result, there was a significant difference for the range of frequency change and continuous time between normal condition and when a dolphin was isolated from others. The pattern of whistle at the dolphin performance hall was five types and the frequency was getting increased slowly in the range of 5~10KHz at normal condition but there were pattern change of 5~20KHz at the isolated condition. Therefore it is thought that these experiments would be valuable for the development of acoustic system.

• Journal of Korean Medical classics
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• v.18 no.4 s.31
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• pp.67-82
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• 2005

지구온난화(地球溫暖化), 식습관(食習慣), 주거환경여약물지오남용(住居環境與藥物之誤濫用), 공치기습열적체어체내(共致其濕熱積滯於體內), 소이유인음정부족이상화치성적병기(所以有因陰精不足而相火熾盛的病機), 기내용시여하(其內容是如下). 기일원인시지구온난화(其一原因是地球溫暖化), 차부단야기급성열성전염병(此不但惹起急性熱性傳染病), 이차야기음부족적허열성질환(而且惹起陰不足的虛熱 性疾患). 기이원인시식습관(其二原因是食習慣), 차적체습열이유발상화(此積滯濕熱而誘發相火), 차유발과도적양화작용(且誘發過度的陽化作用), 소이야기음부족적병기(所以惹起陰不足的病機). 기삼원인시주거환경(其三原因是住居環境), 차방기기적소통(此防其氣的疏通), 소이습열적체어체내이유발음부족적병기(所以濕熱積滯於體內而誘發陰不足的病機). 기사원인시약물적오남용(其四原因是藥物的誤濫用), 차치기열적잠복(此致其熱的潛伏), 소이유발음부족(所以誘發陰不足). 여차유발상화적현대환경(如此誘發相火的現代環境), 야기허열성질환(惹起虛熱性疾患). 소이증가태열여성인병(所以增加胎熱與成人病), 야취증가인과도적양화작용이불임질환(也就增加因過度的陽化作用而不姙疾患), 이차재정서적면(而且在情緖的面), 증가공격적여폭력적정서(增加攻擊的與暴力的情緖).

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.2
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• pp.68-77
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• 2009

1967년 처음 보고된 메타 물질은 이론적 제안에 머물러 있던 그 독특한 특성이 2000년대에 들어서 실험적 검증을 거치면서 물리학과 공학 분야의 새로운 연구 분야로 크게 각광받고 있다. 특히 그 구현 기술의 획기적인 발전으로 음의 굴절률뿐만 아니라 자연계에서 얻을 수 없는 유전율과 투자율 구현이 가능해짐으로써 기존 기술의 단순한 대체 기술이 아닌 새로운 응용 분야를 열 수 있는 기술로 평가 받으며 전례 없는 응용 가능성을 보여주고 있다. 그 중에서도 메타 물질 기반의 전자기파 투명화 기술은 기존 스텔스 기술보다 훨씬 경제적 이라는 큰 장점과 함께 가시광선 대역에 응용되어 투명 망토를 구현할 수 있는 꿈의 기술로 주목받고 있다. 본 논문에서는 전자기파가 휘어서 진행함으로써 마치 자유공간과 같은 효과를 나타내는 것을 기본 원리로 하는 좌표계 변환을 이용한 메타 물질 기반 전자기파 투명화 기술의 기본 이론과 현주소, 향후 과제에 대해서 다룬다.

• Management & Information Systems Review
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• v.34 no.5
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• pp.213-231
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• 2015

In this paper, I examine whether the listed companies in Korea tend to manage operating cash flows upward via classification shifting after the adoption of K-IFRS. As proxies for cash flow management, I derive a measure of abnormal operating cash flows borrowing from Lee(2012). Alternative proxies include a series of categorical variables designed to identify the types of classification shifting of interest and dividend payments among others, in the statement of cash flows. Higher level of estimated abnormal operating cash flows, and the classification of interest/dividend payments in non-operating activity sections are considered to indicate the managerial intention to maximize reported operating cash flows. I consider several potential incentives to manage operating cash flows, which include financial distress, the credit rating proximity to investment/non-investment cutoff threshold, avoidance of negative or decreasing operating cash flows relative to previous period and so forth. In a series of empirical analyses, I do not find evidence in support of the opportunistic classification shifting explanation, inconsistent with several previous literature in Korea. In contrast, I observe negative associations between the CFO management proxies and selected incentives, which suggest that the classification is likely to represent above average cash flow performance rather than opportunistic motives exercised to maximize reported operating cash flows. I reckon that this observation is, in part, driven by the K-IFRS requirement to maintain temporal consistency in classifying interest and dividend receipts/payments in cash flow statement.

• Journal of Korean Society of Transportation
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• v.17 no.5
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• pp.123-135
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• 1999

The rapid increase of Passenger cars which is caused by the discomfort of Public transit and the Preference of automobiles is the major factor of increasing traffic congestions in Seoul With the point that leading the automobilists to the Public transit can be the most important Policy to ease these traffic congestions, this study focuses on the behavioral aspects of company employees and university students and investigates factors influencing bus ridership. To be brief, by estimating bus ridership through count models, this study investigates factors which influence bus ridership and elicits Political suggestions which lead automobilists to Public transit. The Purpose in this study is the application of appropriate count data model. The count data models have been widely applied to the economic area from the middle of the 1980s and to transportation aspect mainly in the foreign countries from the latter half of the 1980s. Even though a few studies in this country employed count data model to count data. all of them were Poisson regression models without suitable tests for the importance of the model specification. In the end, as the result of statistical test, negative binomial regression model which is suitable for overdispersed data was found to be appropriate for the data of weekly bus ridership. To emphasize the importance of model specification, both of poisson regression model and negative binomial regression model were estimated and the results were compared.

• KDI Journal of Economic Policy
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• v.34 no.1
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• pp.29-52
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• 2012

During the global financial turmoil in 2007-2008, deviation from the covered interest parity (CIP) between the Korean won and US dollar through the foreign exchange swap has escalated in its magnitude beyond 1,000bp in November 2008, and it still persists around 100bp level. In this paper, we examine a newly developed margin based asset pricing model using Kalman filter approach and show that the escalation of the CIP deviation is found to be significantly related to the global dollar funding illiquidity and country-specific funding conditions. Furthermore, we find evidence that the poor funding conditions (or higher margins) are driven by the general money market illiquidity and may lead to higher funding illiquidity, which suggests the reinforcing effects of the liquidity spiral. We also show that the supply of dollar liquidity and improved funding conditions help alleviate the deviations from the parity, however the persistent anomaly is found to be related to the high level of volatility in the FX swap market.