• 제목/요약/키워드: Record Length

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A Study on the Heat Transfer Performances in Sintered Pipes (소결 코팅 파이프의 열전달 성능에 관한 연구)

  • Park, Ki-Ho;Lee, Ki-Woo;Kim, Seong-Il;Jeong, Dae-Heon
    • Proceedings of the SAREK Conference
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.436-439
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    • 2008
  • This paper is to research the heat transfer performance of the sintered pipe. Recently, oil prices is to be 127 $ per barrel, we expect higher costs this summer. We promote alternative fuels, after oil and gasoline prices reached record highs. The governments have made efforts to avoid future crisis by continuing the move toward renewable energy and energy saving. In this paper, we have fabricated a sintered pipe, the heat transfer performance of sintered pipe is achieved experimentally. The pipe is copper tube of outer diameter of 15.88 mm, the length of the pipe is 800 mm. Based on the experimental results, it is shown the overall heat transfer coefficient of sintered pipe is increased as compared with that of a straight pipe, is equal as compared with that of a spiral pipe. The overall heat transfer coefficient was $0.075{\sim}0.09\;kW/^{\circ}C$

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Diversity of Fungi from Dokdo Island Soil, Korea and Their Antimicrobial and Hydrolytic Enzyme Activity

  • Lee, Hye Won;Lee, Hyang Burm
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2014년도 추계학술대회 및 정기총회
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    • pp.47-47
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    • 2014
  • Dokdo island is located in the northeastern part of Ulleungdo, known as volcanic island. In total, 53 fungal isolates were isolated from Dokdo island soil sample, using dilution plate technique. The isolates were identified on the basis of morphological characteristics and rDNA ITS sequence analysis. Out of them, 41 isolates were identified at the level of species. The dominant fungal species and genera included Fusarium spp., Mucor sp., Clonostachys spp., and Trichoderma sp. The % sequence identity (the number of matches/the complete alignment length) values via NCBI BLAST searching of EML-IF9, EML-MF30-1 and EML-DDSF4 represented 97.19% (485/499) with Clonostachys cf. rosea (GenBank accession no. KC313107), 98.33% (472/480) with Metarhizium guizhouense (GenBank accession no. HM055445), and 100% (350/350) with Mortierella oligospora (GenBank accession no. JX976032), respectively. Three species of C. rosea, M. guizhouense and M. oligospora represented new records of fungi from Dokdo island, Korea. The antimicrobial activities of the fungal strains varied with tested. Two isolates (EML-MFS30-1 and EML-IF9) showed antifungal activity against several fungi including Fusarium oxysporum and Rhizotonia solani. Clonostachys rosea (EML-IF9) showed strong hydrolytic enzyme activity. Our results showed that the antagonistic fungi including Clonostachys rosea will be used as potential biocontrol agents for control of fungal diseases.

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The Statistical Model for Predicting Flood Frequency (홍수 빈도 예측을 위한 통계학적 모형)

  • 노재식;이길춘
    • Water for future
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    • 제25권2호
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    • pp.89-97
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    • 1992
  • This study is to verify the applicability of statistical models for predicting flood frequency at the stage gaging stations selected by considering whether the flow is natural condition in the Han River basin. From the result of verification, this statistical flood frequency models showed that is fairly reasonable to apply in practice, and also were compared with sampling variance to calibrate the statistical dfficiency of the estimate of the T year flood Q(T) by two different flood frequency models. As a result, it was showed that for return periods greater than about T=10 years the annual exceedence series estimate of Q(T) has smaller sampling variance than the annual maximum series estimate. It was showed that for the range of return periods the partial duration series estimate of Q(T) has smaller sampling varianed than the annual maximum series estimate only if the POT model contains at least 2N(N:record length)items or more in order to estimate Q(T) more efficiently than the ANNMAX model.

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Development of the Annual Runoff Estimation Model (연유출량 추정모형 개발)

  • 김양수;정상만;서병하
    • Water for future
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    • 제24권3호
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    • pp.95-104
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    • 1991
  • The study was focused on developing a new model to estimate annual runoff. This model can be used to estimate the available water resources for ungaged catchments for long-term water resources development planning. Data used in the model development were daily rainfall and daily runoff of the sample basin with record length from 1945 to 1988 years in Korea. The sample basin selected by consideration whether the flow is virgin and quality of discharge data is good. As a result, 46 stage gaging station were selected. Annual runoff was determined by sum of daily runoff calculated by daily stage data of the sample basin. Also, the annual mean precipitation by using daily rainfall data was estimated and the annual runoff ratio for each sample basin was calculated, and the annual mean runoff ratio was estimated. The linear regression model was proposed and calibrated using auunal mean precipitation values and geomorphological characteristics of the basins. To verify reasonableness of this model, the regression model was applied to the gaging stations which have historical data.

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Use of beta-P distribution for modeling hydrologic events

  • Murshed, Md. Sharwar;Seo, Yun Am;Park, Jeong-Soo;Lee, Youngsaeng
    • Communications for Statistical Applications and Methods
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    • 제25권1호
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    • pp.15-27
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    • 2018
  • Parametric method of flood frequency analysis involves fitting of a probability distribution to observed flood data. When record length at a given site is relatively shorter and hard to apply the asymptotic theory, an alternative distribution to the generalized extreme value (GEV) distribution is often used. In this study, we consider the beta-P distribution (BPD) as an alternative to the GEV and other well-known distributions for modeling extreme events of small or moderate samples as well as highly skewed or heavy tailed data. The L-moments ratio diagram shows that special cases of the BPD include the generalized logistic, three-parameter log-normal, and GEV distributions. To estimate the parameters in the distribution, the method of moments, L-moments, and maximum likelihood estimation methods are considered. A Monte-Carlo study is then conducted to compare these three estimation methods. Our result suggests that the L-moments estimator works better than the other estimators for this model of small or moderate samples. Two applications to the annual maximum stream flow of Colorado and the rainfall data from cloud seeding experiments in Southern Florida are reported to show the usefulness of the BPD for modeling hydrologic events. In these examples, BPD turns out to work better than $beta-{\kappa}$, Gumbel, and GEV distributions.

Morphological description and molecular identification of the newly recorded bothid, Crossorhombus azureus (Bothidae, Pleuronectiformes) postlarva collected from the southern sea of Korea (한국 남해에서 채집된 둥글넙치과(가자미목) 1미기록종, Crossorhombus azureus 후기자어의 형태기재 및 분자동정)

  • SEO, Min-Ju;YU, Hyo-Jae;KIM, Jin-Koo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제57권3호
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    • pp.264-269
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    • 2021
  • A single postlarva (9.72 mm in standard length) specimen of Crossorhombus azureus (Alcock, 1889) belonging to the family Bothidae, was collected using a bongo net from the southern sea of Korea on December 10, 2019. This species is characterized by having spines on post basipterygial processes. It has two eyes located at the opposite side in head, which accordingly belongs to pre-metamorphosis stage. Melanophores are distributed on the dorsal and anal fin base on the right side (blind side), which is regarded as a useful identification key distinguishing C. azureus from congeneric species in their postlarval stage. A molecular analysis based on mitochondrial DNA COI sequences showed that our specimen was closely matched to adult C. azureus (K2P distance = 0.017). As there is no Korean name for the genus Crossorhombus in spite of presence of Crossorhombus kobensis and its Korean name "Go-be-dung-geul-neob-chi" in Korea, we proposed a new Korean name "Dung-geul-neob-chi-sog" for the genus Crossorhombus and "Pa-lang-dung-geul-neob-chi" for the species C. azureus.

First Occurrence of a Pleuronectid Atheresthes evermanni (Pleuronectiformes) from the Middle East Sea, Korea (한국 동해 중부 해역에서 채집된 가자미과(Pleuronectidae) 어류 첫기록종, Atheresthes evermanni)

  • Park, Jeong-Ho;Jang, Yo-Soon;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • 제32권4호
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    • pp.245-250
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    • 2020
  • Two specimens (407~438 mm in standard length) of a pleuronectid Atheresthes evermanni were collected by a gill-net from the coastal waters off Goseong-gun, middle East Sea of Korea. These specimens are characterized by a large mouth, narrow interorbital space, invisible eye at blind side, long and slender gill rakers, emarginated caudal fin, and almost straight lateral line. This is the first record of A. evermanni in Korean waters; we therefore add it to the Korean fish fauna and propose new Korean name, "Hwa-sal-chi-ga-ja-mi-sog" for the genus and "Hwa-sal-chi-ga-ja-mi" for the species, respectively.

Molecular Identification and Morphological Description of Juveniles of the Previously Unrecorded Species Notoscopelus japonicus (Tanaka, 1908) (Myctophidae) in Korean Waters (한국 해역에서 출현한 샛비늘치과(Myctophidae) 어류 1미기록종 Notoscopelus japonicus (Tanaka, 1908) 치어의 분자동정 및 형태기재)

  • Park, Gyeong-Hyun;Kim, Jin-Koo;Ji, Hwan-Sung;Choi, Jung Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제52권4호
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    • pp.424-429
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    • 2019
  • Two juvenile (9.48 and 10.11 mm in standard length) specimens of the lanternfish Notoscopelus japonicus, belonging to the family Myctophidae, were collected from the waters around Busan and Jeju Island in February 2017. This species is characterized by having melanophores along the dorsal side of the body and one photophore (PO5) in front of the pelvic fin. It is distinguished from Benthosema pterotum in having many melanophores on the dorsal side and a single photophore (PO5) on the trunk. N. japonicus is also distinguished from its congeneric N. resplendens and N. caudispinosus in having no melanophores at the base of the anal fin. Analyzing 521 base pairs of the 16S rRNA sequence, the specimens were identical to N. japonicus adults from Japan (K2P distance <0.004). This is the first record of N. japonicus in Korea, and we propose a new Korean name "Deung-jum-saet-bi-neul-chi" for this species.

The Kunjung-mun Sangryangmun of Kyunbok-koong Palace (경복궁(景福宮) 근정문(勤政門) 상량문(上樑門))

  • Seo, byung-pae
    • Korean Journal of Heritage: History & Science
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    • 제34권
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    • pp.196-209
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    • 2001
  • Kunjung-mun Gate the only existing multi-level palace gate from the Chosun Dynasty, is the main fate of Kungjung-jun, the central building of Kyungbok-koong Palace. Sangryangmun(a written record of the construction of the ridge beam) of Kunjung-mun Gate was discovered in a hole under its main beam during the renovation project on September 19th, 2000. At the time of discovery, Sangryangmun was found in its original state as a rolled up scroll. On a clould-patterned, red silk cloth, 78 cm in width and 1200 cm in length, each of all 92 lines of the Kunjung-mun Sangryangmun is comprised of either 7 or 11 brush-written, ornamental "Seal" characters. With an exception of its discoloration, the material is considered well preserved. After its discovery, the National Institute of Cultural Properties stored the document in an airtight container for a permanent preservation. In accordance to the Royal Command at the time, the Kunjung-mun Sangryangmun was composed by Kim Byungi, then written by Lee Donsang on January 19th 1867. This document records the meaning and the process of the repair effort of Kunjung-mun Gate includes the wish for peace and longevity of the Chosun Kingdom and its people.

New records of three lecanid rotifers(Rotifera: Monogononta: Lecanidae) from Korea

  • Yang, Hee-Min;Min, Gi-Sik
    • Journal of Species Research
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    • 제10권3호
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    • pp.262-266
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    • 2021
  • In this study, three lecanid rotifer species were newly recorded in Korea: Lecane inermis (Bryce, 1892), L. furcata (Murray, 1913), and L. nana (Murray, 1913). Most of the lecanid rotifers recorded in Korea have been collected from stagnant water, and Lecane furcata and L. nana were collected from a reservoir. In contrast, L. inermis was found in a soil sample. Lecane inermis is the first illoricated lecanid species reported in Korea. This species is distinguished from other illoricated species by its toes with relatively long claws. Lecane furcata is the most common lecanid rotifer in submerged vegetation. The morphological characteristics of its lorica are similar to many other lecanid rotifers, but it can be distinguished by its completely fused toes with a terminal fissure, an absence of antero-lateral spines, and the ratio of lorica/toe length. Lecane nana is most similar to L. tryphema Harring & Myers, 1926, but can be distinguished by the toe tips curved outwards. The three species in this study are considered to have a cosmopolitan distribution and have been recorded in many Asian countries. In this paper, we describe the morphological characteristics of the three lecanid species with trophi structures observed by scanning electron microscope.