• 말소리와 음성과학
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• 제9권4호
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• pp.19-25
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• 2017

The current study focused on the production of geminate nasal consonants across different word boundary types in Korean as a function of speech style to investigate whether temporal properties are preserved across varying speaking rates. Assimilated geminates in Korean, known as true geminates, are produced with distinctively longer consonant duration compared to singletons. Despite a large body of literature for geminates across different languages, geminates in Korean have been relatively less investigated with respect to the durational patterns in relative terms and temporal variabilities. In this study, singletons, word-internal geminates and word-boundary (fake) geminates produced by ten native Seoul Korean speakers were compared in terms of absolute consonant closure duration, preceding vowel duration, the relative ratios (consonant-to-preceding vowel duration) as well as the temporal variabilities in speech production. The results showed that word-internal geminates were produced with longer consonant duration and greater temporal variabilities than singletons and word-boundary geminates in absolute duration, indicating relatively greater flexibility in timing. However, only word-internal geminates were produced with distinctively longer consonant duration with significantly lower variability in relative duration regardless of speech styles. The results provide some insight into the representation of temporal information in the production of Korean geminate consonants.

• 말소리와 음성과학
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• 제15권3호
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• pp.9-16
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• 2023

The current study investigated the influence of age of L2 acquisition (AOA) and length of residence (LOR) in the L2 setting country on the production of voicing-conditioned vowel duration and spectral qualities in English by Korean learners. The primary aim was to explore the ways in which the language-specific phonetic features are acquired by the age of onset and L2 experience. Analyses of the archived corpus data produced by 45 native speakers of Korean showed that, regardless of AOA or LOR, absolute vowel duration was used as a salient correlate of voicing contrast in English for Korean learners. The accuracy of relative vowel duration was influenced more by onset age than by L2 experience, suggesting that being exposed to English at an early age may benefit the acquisition of temporal dimension. On the other hand, the spectral characteristics of English vowels were more consistently influenced by L2 experience, indicating that immersive experience in the L2 speaking environment are likely to improve the accurate production of vowel quality. The distinct influence of the onset age and L2 experience on the specific phonetic cues in L2 vowel production provides insight into the intricate relationship between the two factors on the manifestation of L2 phonological knowledge.

• International Journal of Industrial Entomology and Biomaterials
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• 제20권2호
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• pp.69-74
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• 2010

Feeding is an important aspect of insect nutrition which in turn supports growth, development, reproduction and survival. The impact of quantitative feeding on nutritional parameters of fifth instar Antheraea mylitta larvae was studied by providing fresh leaves of Terminalia tomentosa for 1 to 4 times a day. All the parameters improved upon providing fresh diets more times over the single diet (1FD). The absolute body weight increased with increase in number of feeds/day significantly (P<0.001). While the maximum weight recorded was 29.61 g in 1FD, the respective weights for two feeds/day (2FD), three feeds/day (3FD) and four feeds/day (4FD) were 39.41 g, 40.63 g and 42.66 g respectively. Feeding period and instar duration were declined (P<0.001) and survival increased significantly (P<0.001) upon increase in the number of diets. Nutritional indices like ingestion, digestion, relative consumption rate (RCR), relative growth rate (RGR) and gain in body weight increased significantly with the increase in number of feeds/day, but approximate digestibility (AD) and efficiency of conversion of ingested food (ECI) declined, while efficiency of conversion of digested food (ECD) did not change.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.531-536
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• 1999

This study was carried out to derive optimal design drought flows by the Weibull-3 and Wakeby distributions for the annual drought flows series at seven watersheds along Han, Nagdong, Geum, Yeongsan and Seomjin river systems. L-coefficient of variation , L-skewness and L-kurtosis were calculated by the L-moment ratio respectivley. Parameters were estimated by the Methods o fL-Moments with continuous duration. Design drought flows obtained by Methods of L-Moments using Weibull plotting positions formula in the Weibull-3 and Wakeby distributions were compared by the Relative Mean Errors(RME), Relative Absolute Errors (RAE) and Root Mean Square Errors(RMSE). It has shown that design drought flows by the Wakeby distribution using method of L-moments are much closer to those of the observed data in comparison with those obtained by the Weibull-3 distribution using method of L-moments.

• 한국수자원학회논문집
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• 제41권9호
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• pp.873-884
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• 2008

본 연구에서는 서로 다른 지속기간을 가지는 강우자료간의 스케일 성질을 이용하여 확률강우량을 추정하는 방법을 알아보고, 국내 강우자료에 대해서 그 적용성을 살펴보고자 하였다. 기상청 지점중에서 기록기간이 비교적 장기간인 22개 지점에 대해서 지점빈도해석을 통한 확률강우량과 스케일 성질을 활용한 확률강우량간의 정확도를 비교해 본 결과, 시간단위자료를 사용할 경우 대부분 절대상대오차가 10 % 미만인 결과를 얻을 수 있었고, 각각의 지속 기간별로 적용가능한 재현기간을 살펴본 결과 연구에 사용된 총 14개의 재현기간 중에서 대부분 8개 이상의 재현기간에 대해서 적용이 가능한 것으로 나타났다. 적용예로서 대구지점의 지속기간 1시간 강우자료를 바탕으로 지속기간 10분${\sim}$50분까지의 확률강우량자료를 스케일 성질을 이용하여 산정한 결과 지속기간 10분을 제외하고는 모두 절대상대오차 10 % 내외의 정확도를 가지는 것으로 나타났다. 따라서 스케일 성질을 이용하여 미계측 강우지속기간의 확률강우량을 추정할 수 있을 것으로 판단된다.

• 한국농공학회지
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• 제38권2호
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• pp.108-122
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• 1996

This study was to introduced estimation model for optimum probabilistic rainfall intensity on hydrological area. Originally, probabilistic rainfall intensity formula have been characterized different coefficient of formula and model following watersheds. But recently in korea rainfall intensity formula does not use unionize applyment standard between administration and district. And mingle use planning formula with not assumption model. Following the number of year hydrological duration adjust areal index. But, with adjusting formula applyment was without systematic conduct. This study perceive the point as following : 1) Use method of excess probability of Iwai to calculate survey rainfall intensity value. 2) And, use method of least squares to calculate areal coefficient for a unit of 157 rain gauge station. And, use areal coefficient was introduced new probabilistic rainfall intensity formula for each rain gauge station. 3) And, use new probabilistic rainfall intensity formula to adjust a unit of fourteen duration-a unit of fifteen year probabilistic rainfall intensity. 4) The above survey value compared with adjustment value. And use three theory of error(absolute mean error, squares mean error, relative error ratio) to choice optimum probabilistic rainfall intensity formula for a unit of 157 rain gauge station.

• 대한토목학회논문집
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• 제32권5B호
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• pp.267-272
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• 2012

기후변화로 증가하는 홍수피해를 대처하기 위해 여러 예측 방법들이 개발되고 있다. 홍수예측의 가장 핵심 요소는 홍수예측을 위한 수문모델의 입력자료로 사용하는 강우에 대한 정확하고 신속한 예측이다. 기존의 레이더 강우를 이용한 Nowcasting 보다 더 많은 대응시간을 확보할 수 있는 중소규모의 기후모델인 WRF(Weather Research Forecast)-ARW(Advanced Research WRF)를 소개하고, 이를 한반도 중부지방의 청미천 지역에 적용하려 한다. WRF-ARW의 적용기간은 2006년 7월 11일부터 7월 23일까지이며 이 결과를 청미천 유역에 있는 강우 관측소들(생극, 삼죽, 설성)의 실제 강우관측소의 관측 값과의 비교에 의해 이 강우 사상에 대해 Thomson scheme(미세물리)와 Kain-Frisch scheme(적운형 매개변수)의 조합이 청미천유역에서 가장 적합한 기후물리 조합이며 Mean Absolute Relative Error를 통해 세 개의 강우관측지점이 0.45 이상의 값을 나타내었다.

• 대기
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• 제21권4호
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• pp.361-371
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• 2011

In this study, characteristics and trends of tropical night (TN) are investigated by using the KMA 14 observation data for the recent 50 years (1958-2007) over South Korea. The TN is defined as a day with a daily minimum temperature exceeds the absolute threshold temperature ($25^{\circ}C$), and the relative deviation from normal temperature, 95th percentile of all observed daily minimum temperature. Although the spatial distribution of TN occurrence depends on the choice of the definitions, the frequency of TN shows strong spatial and interannual variations with the minimum at high land area (Chupungnyeong and wet years) and maximum at southern coastal area and large city area (Jeju, Busan, Seoul, Daegu). Most of TN occurs in August (56%) and July (41%), and the duration date of TN is proportional to the frequency of TN without regard to the definition method. In general, increasing trends are found in the TN time series without regard to the analysis method, but the trends are clearly depending on the analysis period and geographic locations. Decreasing trends are prominent during the most of analysis period, especially until the mid of 1990, whereas strong increasing trends are found during recent 30 years (1988-2007), especially at Jeju, Ulsan, Daegu and Pohang. Also the severity of TN is significantly increased in recent years.

• 전기학회논문지
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• 제62권8호
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• pp.1066-1073
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• 2013

This paper illustrates newly an outage cost impact index function(OCIIF). The assessment of the OCIIF is described using the Web Based Online Real-time Outage Cost Assessment and Information System(WOROCAIS) for power system outage cost assessment in Korea. The proposed OCIIF is not absolute but relative outage cost impact index function in view point of outage time using web based survey method for outage cost assessment. While conventional methodology does not consider short time outage cost assessment, the proposed OCIIF reflects short time outage. SCOF(Sector Customer Outage Function) in stead of the traditional SCDF(Sector Customer Damage Function) is defined and proposed newly in this paper. Based the SCOF, AVLL(Average Value of Loss Load) is newly proposed. The OCIIF is demonstrated by WOROCAIS in case study around 2,000 sample data surveyed by KEPCO in South Korea in recent.

• 무역상무연구
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• 제53권
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• pp.315-336
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• 2012

In year 2011 export volume of South Korea surpassed 500billion USD and overall trade volume has exceeded one trillion USD. South Korea is ranked at 7th in the world by its export volume. Such an expansion of the trade volume leads to growth in customs clearance service demand. However, there are only handfuls of studies on the efficiency of customs clearance service which customs broker provide. If the efficiency in this study is not absolute, it shows relative efficiency to decision making unit. In this research survey was conducted targeting members of Korea Customs Brokers Association. Based on the survey improvement plans to enhance efficiency of customs clearances are as follows. First, rationalize the customs broker fee. Second, setup batch processing system to improve efficiency of the work process. Third, develop new area of task such as FTA and AEO certification. Forth, raise service quality by improving professionalism of customs brokers. Fifth, work efficiency of the office in the capital area will increase. Sixth, when inspecting import export cargo, customs broker should attend at the scene by their choice. Meanwhile, difference analysis on competent customs, type of office, and duration of the business was done but all the aspects were rejected. Such aspects does not influence on its effectiveness.