• Title/Summary/Keyword: $V_1$ 속도

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Seasonal Distribution of Vibrio spp. in the Jeonam Archipelago Marine Ranching Ground (전남 다도해 바다목장 비브리오속 세균의 계절적 분포)

  • Kim, Mal-Nam;Lee, Han-Woong
    • Journal of fish pathology
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    • v.20 no.3
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    • pp.229-235
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    • 2007
  • Cell number of Vibrio spp. was examined for the surface and bottom sea water harvested from the 9 stations in the Jeonam Archipelago Marine Ranching Ground in 2006~2007. Species population composition and dominant species were analyzed as well. The largest number of Vibrio spp. was detected in summer (June, 2007) among the 4 seasons with the surface and bottom sea water samples of 5.4~93.2 cfu㎖-1 and 1.0~53.1 cfu㎖-1. respectively. In winter (January, 2007), Vibrio spp. was not detected at all except that one station from which 0.2 cfu㎖-1 of Vibrio spp. was counted in the surface sea water sample. Cell numbers were 0~11.9 cfu㎖-1 and 0~8.3 cfu㎖-1, respectively, in the surface and bottom sea water samples retrieved in spring (April, 2007), and the corresponding sea water samples in autumn(November, 2006) were contaminated with 0.1~21.4 cfu㎖-1 and 0~2.9 cfu㎖-1, respectively. Species population composition of Vibrio spp. was found to be V. parahaemolyticus, V. alginolyticus and V. cholerae non-01 among which V. parahaemolyticus and V. alginolyticus were dominant in all seasons. V. alginolyticus was detected from all stations even in the winter season indicating that this species seems to be less temperature dependent than the other Vibrio spp..

Site Characterization using Shear-Wave Velocities Inverted from Rayleigh-Wave Dispersion in Wonju, Korea (레일리파 분산을 역산하여 구한 횡파속도를 이용한 원주시의 부지특성)

  • Kim, Chungho;Ali, Abid;Kim, Ki Young
    • Geophysics and Geophysical Exploration
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    • v.17 no.1
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    • pp.11-20
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    • 2014
  • To reveal shear-wave velocities ($v_s$) and site characterization of Wonju, Korea, Rayleigh waves were recorded at 78 sites of lower altitude using 12 to 24 4.5-Hz vertical geophones for 20 days during the period of February to September 2013. Dispersion curves of the Rayleigh waves obtained by the extended spatial autocorrelation method were inverted using the damped least-squares method to derive $v_s$ models. From these 1-D models, the average $v_s$ to a depth of 30 m ($v_s30$), $v_s$ of weathered rocks, depths to these basement rocks, and average $v_s$ of the overburden layer were derived to be $16.3{\pm}0.7m$, $576{\pm}8m/s$, $290{\pm}7m/s$, and $418{\pm}13m/s$, respectively, in the 95% confidence range. To determine adequate proxies for $v_s30$, we computed correlation coefficients of $v_s30$ with topographic slope (r = 0.46) and elevation (r = 0.43). An empirical linear relationship is presented as a combination of individually estimated $v_s30$ with weighting factors of 0.45, 0.45, and 0.1 for topographic slope, elevation, and mapped lithology, respectively. Due to a weak correlation between $v_s30$ obtained from inversion of dispersion curves and the proxy-based estimation (r = 0.50), however, the relatively large error range should be considered for applications of this relationship.

A comparative study on the characteristics of each version of object detection model YOLO (객체탐지모델 YOLO의 버전별 특성 비교 연구)

  • Joon-Yong Kim
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2023.07a
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    • pp.75-78
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    • 2023
  • 본 논문은 객체탐지 모델 중 주류를 이루고 있는 YOLO의 v1부터 v8까지의 특성을 비교 분석하여 각각의 버전에 최적화할 수 있는 모델에 대한 연구이다. 연구 결과 v1, v2는 정확성이 최우선인 모델에 적합하다. 반면, v3, v4는 속도가 우선인 모델에 적합하다. 또한 v5, v6는 정확도와 속도 사이의 균형이 필요한 모델에 적합하다는 결론을 얻었다. v7, v8은 메모리 및 컴퓨팅 성능에 제약이 있는 경우 주로 적용이 가능하며, 적은 연산과 저 메모리 사용으로 객체를 탐지하여 포즈추정이나 객체 추적 등을 적용할 모델에 적합하다는 결과를 확인하였다.

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Heterogeneity Analysis of the 16S rRNA Gene Sequences of the Genus Vibrio (Vibrio 속 16S rRNA 유전자 염기서열의 이질성 분석)

  • Ki, Jang-Seu
    • Korean Journal of Microbiology
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    • v.45 no.4
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    • pp.430-434
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    • 2009
  • Bacterial 16S rRNA gene sequences have been widely used for the studies on molecular phylogeny, evolutional history, and molecular detections. Bacterial genomes have multiple rRNA operons, of which gene sequences sometimes are variable. In the present study, heterogeneity of the Vibrio 16S rRNA gene sequences were investigated. Vibrio 16S rRNA sequences were obtained from GenBank databases, considering the completion of gene annotation of Vibrio genome sequences. These included V. cholerae, V. harveyi, V. parahaemolyticus, V. splendidus, and V. vulnificus. Chromosome 1 of the studied Vibrio had 7~10 copies of the 16S rRNA gene, and their intragenomic variations were less than 0.9% dissimilarity (more than 99.1% DNA similarity). Chromosome 2 had none or single 16S rRNA gene. Intragenomic 16S rRNA genotypes were detected at least 5 types (V. vulnificus #CMCP6) to 8 types (V. parahaemolyticus #RIMD 2210633, V. harveyi #ATCC BAA-1116). These suggest that Vibrio has high heterogeneity of the 16S rRNA gene sequences.

Vibration-to-Vibration Energy Transfer Between HF and DF in the Mixture (HF와 DF 혼합계내에서의 상호간 진동-진동 에너지 이동)

  • Chang Soon Lee;Yoo Hang Kim
    • Journal of the Korean Chemical Society
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    • v.28 no.1
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    • pp.26-33
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    • 1984
  • The rate constants for the following vibration-to-vibration energy exchange reactions have been calculated theoretically for the temperature range from 300 to 800K and for n = 2 to 5. HF(v=n) + DF(v=0) ${\to}$ HF(v=n-l) + DF(v=l) + ${\Delta}E$(a) DF(v=n) + HF(v=0) ${\to}$ DF(v=n-l) + HF(v=l) + ${\Delta}E$(b) In calculation the loosely-held, non-rigid dimer collision model and semiclassical method have been employed. The results show that the rate constants for the processes (a) are much greater than those for the processes (b). Also, it is found that the rate constants for the processes (a) increase with decreasing temperature and with increasing quantum number, while those for the processes (b) show the opposite tendencies. These findings are explained in terms of the sign and magnitude of the energy mismatch, ${\Delta}E$.

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여름철 광안리 해수 중의 비브리오속의 분포 조사

  • 박미연;김현진;장동석
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.223-224
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    • 2001
  • 생선회를 즐겨먹는 우리나라에서는 여름철에 비브리오균에 의한 식중독이 빈번하게 발생하고 있다. 현재까지 40여종의 비브리오속 세균이 검출되었으며, 이중 사람에게 병원성을 나타내는 것은 12종(V cholerae, V. parahaemolyticus, V. cholerae non-O1, V. alginolyticus, V. vulnificus, V. fluvialis, V. hollisae, V. mimicus, V. metschikovii, V. cincinnatiensis, V. damsela, V. furnissi)으로 알려져 있다. (중략)

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Analysis Study on the Microscopic Characteristics of Freeway Free Flow Speed (고속도로 자유교통류 속도의 미시적 특성에 관한 연구)

  • Yoon, Byoung Jo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.2D
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    • pp.105-111
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    • 2010
  • Operating speed is one of key elements in the design and operation of freeway. Few studies have been carried out macroscopically to find characteristics of free-flow speed (FFS) using small sample size and not considering the conditions of traffic volume and the effects of hour periods. As an attempt to find out the characteristics of FFS, this study microscopically analysed both the distributions of freeway FFS and percentile speeds according to traffic volume and daily hour periods using huge sample size. It was found out that speed distributions are changed and showed different behaviors under the conditions of traffic volumes(1-5 veh/30sec) and daily hour periods(0-5, 6-8, 9-11, 12-19, 20-23). V85(85th percentile speed) at morning, night, and midnight period decreases according to increase in traffic volume respectively, whereas V85 at day time does not show considerable differences. So the behaviors of V85 according to hour periods dramatically changed according to the increase in traffic volume.

A Study on the Characteristics of Dynamic Elastic Modulus in GyeongGi Gneiss Complex by Down Hole Test (하향식 탄성파를 통한 경기 편마암의 동탄성 특성연구)

  • Lee, Byok-Kyu;Lee, Su-Gon
    • The Journal of Engineering Geology
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    • v.18 no.4
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    • pp.371-379
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    • 2008
  • In this study, seismic elastic wave and dynamic elastic modulus properties are investigated by down-hole seismic tests that were applied to the 11 gneiss area. The research results show that the realtionship between the two properties are $V_s=0.5589{\times}V_p$ in gneiss. The relationship between the two properties are separated into two groups. Group 1 is influenced mainly by the specific gravity of rock, but group 2 is influenced mainly by the joint aperture. As weathering progresses, group 1 clearly shows a decreasing tendency. In fresh and slightly weathered rock-mass, correlations between $V_p$ and dynamic elastic modulus is expressed in linear line but in moderately-highly weathered rock-mass, correlations between $V_p$ and dynamic elastic modulus is expressed curve as a quadratic function. Correlations between $V_s$ and dynamic elastic modulus are analyzed similar with a $V_p$ case.

Physical property evolution along gas hydrate saturation for various grain size distribution (다양한 입도분포에서의 하이드레이트 함유량에 따른 물성 변화 양상 연구)

  • Jung, Jaewoong;Lee, Jaehyung;Lee, Joo Yong;Lee, Minhui;Lee, Donggun;Kim, Sejoon
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.149-149
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    • 2011
  • 청정 에너지원으로 높은 잠재력을 가지고 있는 가스하이드레이트는 상업적 기술개발이 미확보된 상태임에도, 우리나라에서 부존이 직접적으로 확인되었기 때문에 에너지원으로서 그 중요성이 부각되고 있다. 현재 전세계적으로 가스하이드레이트 개발 및 생산에 관한 연구가 활발히 진행되고 있으며 이에 대한 기초자료로서 가스하이드레이트가 함유된 퇴적층의 물성자료가 필요하다. 이에 따라 본 연구에서는 입도 분포별 총 5가지의 미고결 시료를 대상으로 투과도, p파속도, 전기비저항 측정을 수행하였다. 연구에 사용된 미고결 시료는 Hama#5($774{\mu}m$), #6($485{\mu}m$), #7($258{\mu}m$), #8($106{\mu}m$) 4가지와 Hama#6과 Hama#7을 1:1($371{\mu}m$)로 혼합하여 사용하였다. 실험에 사용된 장비는 가스하이드레이트를 인공적으로 생성시키기 위해 퇴적층을 모사할 수 있는 고압셀과 자료획득장비, 유체 주입장비, 온도 유지장비이다. 또한 투과도 측정에는 차압계, 전기비저항 측정에 RLC meter, p파속도 측정에 음파 송수신장비를 사용하여 각각의 물성을 측정하였다. 실험과정을 단계별로 요약하면 먼저 시료를 고압셀에 충진한 뒤 주입된 물의 양으로부터 공극률을 측정하고, 절대 투수계수를 측정하였다. 그 후, 메탄가스를 주입하여 퇴적층 내 수포화도(water saturation)를 잔류상태(irreducible saturation)로 유지시키고 메탄가스를 추가적으로 주입하여 원하는 압력까지 가압한 뒤 온도를 $1^{\circ}C$로 낮추었다. 가스하이드레이트의 생성은 급격한 압력강하로부터 알 수 있다. 최종적으로 가스하이트레이트가 함유된 퇴적층의 상대 투수계수를 측정하기 위해 메탄가스를 주입하였고 각각의 측정장비를 통해 전기비저항 및 p파 속도를 측정하였다.$V_g$, $V_h$, $V_w$, $V_ss$는 각각 가스의 부피, 하이드레이트의 부피, 물의 부피, 모래의 부피이다. 또한 수포화도, $S_w=\frac{V_w}{V_v}$이며 하이드레이트 포화도, $S_h=\frac{V_w}{V_v}$, 가스 포화도, $S_g=\frac{V_g}{V_v}$로 정의된다. 본 실험의 결과 투과도는 가스의 부피비, $\frac{V_g}{V}=nS_g$에 민감한 반응을 보였으며, 비저항은 공극수의 부피비, $\frac{V_w}{V}=nS_w$에 민감한 반응을 보였다. 또한 p파 속도는 고체의 부피비, $\frac{V_s+V_h}{V}=n(1-S_h)$에 민감한 반응을 보였다. 이러한 실험의 결과는 가스하이드레이트 개발, 생산 연구에 있어 기초 물성자료로 활용되는데 도움을 줄 것이다.

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Identification and use of correct scientific names of Vigna angularis var. nipponensis (Ohwi) Ohwi & Ohashi and V. nakashimae (Ohwi) Ohwi & Ohashi in Korea (콩과 동부속(Vigna, Leguminosae) 새팥과 좀돌팥의 동정 및 학명표기)

  • Lee, Jeongran;Baek, Hyung-Jin;Yoon, Mun-Sup;Cho, Gyu-Taek;Kim, Chang-Yung
    • Korean Journal of Plant Taxonomy
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    • v.36 no.3
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    • pp.217-225
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    • 2006
  • Among the seven taxa of the genus Vigna, Leguminosae vegetated in Korea peninsula, only two taxa, V. unguiculata subsp. unguiculata and V. vexillata var. tsusimensis, are recognized in Vigna. The rests are still remained in the genus Phaseolus in many floras and illustrations of Korea although they were placed into the genus Vigna by Verdcourt in 1970. There has been misidentification between V. angularis var. nipponensis and V. nakashimae because of their similar morphological characters and habit. It was also found that V. nakashimae has not been recorded in many floras. Objectives of this study are 1) to discuss the taxonomic differences between Vigna and Phaseolus, 2) to have a recommendation for using correct scientific names of Vigna taxa, 3) to discuss the taxonomic characteristics of the subgenus Ceratotropis, and 4) to provide a simple taxonomic key of V. angularis var. nipponensis and V. nakashimae.