• 제목/요약/키워드: Q&As

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졸참나무림의 식생구조와 생태적지 (Vegetation Structures and Ecological Niche of Quercus serrata Forests)

  • 이미정;이선;김효정;지윤의;송호경
    • 한국환경복원기술학회지
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    • 제7권1호
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    • pp.50-58
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    • 2004
  • The aim of this study was to characterize the forest vegetation structure and site of Quercus serrata forest for ecological forest management and ecological niche. The results are as follows : The chemical properties of Q. serrata forest soil were 0.24% of total nitrogen, 8.27 of organic matter, 74ppm of available phosphorous, 1.64(me/100g) of Ca, 0.22(me/100g) of Mg, 0.74(me/100g) of K and 9.3(me/100g) of cation exchangeable capacity. The dominant species in Quercus serrata forest were Quercus serrata, Quercus acutissima, Quercus variabilis, Quercus mongolica, Styrax obassia, Fraxinus rhynchophylla and Styrax japonica. DBH analysis showed that Quercus serrata seems to remain as a dominant species for the present because they had random distribution based on few of big individuality, many of small and middle individuality. But the Q. serrata community is competing with Q. mongolica and F. rhynchophylla, whose density of small individuality has increased. With the classification of TWINSPAN, Q. serrata forest was classified three groups, such as Q. serrata-Acer mono, Q. serrata, Q. serrata-Q. acutissima communities. The results of the correlation analysis of Q. serrata major communities and environment factors are as follows; Q. serrata-A. mono community was found relatively in high elevated and eastern and northern area that has relatively high percentage organic matter. Also Q. serrata community was found in high elevated and eastern and northern area that has high percentage organic matter. Q. serrata-Q. acutissima community was found in low elevated and southern and western area that has low percentage organic matter.

한국산(韓國産) 참나무과(科) 수종(樹種) 도관구조(道管構造)에 관(關)한 연구(硏究)(II) -도관벽(導管壁)의 수식구조(修飾構造)- (A Study on the Vessel Structure of Fagaceae Species in Korea (II) -Micromorphology of Vessel Wall Sculpture-)

  • 이성재;이원용
    • Journal of Forest and Environmental Science
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    • 제8권1호
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    • pp.51-66
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    • 1992
  • This study was carried out to investigate the micromorphology of vessel wall sculpture such as shape of perforation plate, perforation rim, steepness of perforation plate, occurrence of vestured pit, warty layer and ray-vessel pitting on 13 species of Fagaceae in Korea. The results were summarized as follows ; 1. In the species examined, all sample species except Fagus crenata var. multinervis have simple perforation plate. But Fagus crenata var. multinervis has simple and scalariform perforation plate (it was called to combination perforation plate) in a tree stem. 2. The shapes of perforation rim could be classified into five types; Type A without tail, Type B with small tail on both sides, Type C with long tail on both sides, Type D with tail only one side and Type E with the very short interval between perforations. Among five types, Type Band C have higer frequency of distribution than the others. 3. The steepness of perforation plate measured was about 20 degree on pore zone and 43 degree on outside parts of pore zone. 4. Species with vestured pit were Q. aliena, Q, dentata, Q. variabilis, Fagus crenata var. multinervis, Castanopsis cuspidata var sieboldii, Q. acuta, Q. stenophylla, and Q. glauca. But the extent of vesturing was very slight and vestured pits were observed mainly in ray-vessel pit of some vessel elements. 5. Species with warty layer on the inner surface wall of all vessel elements were Q. acuta, Q. stenophylla, Q. glauca, Fagus crenata var. multinervis and species with warty layer of some vessel elements were Q. aliena, Q, dentata, Q. variabilis, Castanopsis cuspidata var. sieboldii. 6. Species with palisade ray-vessel pit were Q. acuta, Q. stenophylla, Q. glauca, Castanea crenata, Castanea bungeana, Q. aliena, Q. serrata, Q. mongolica, and species with scalariform ray-vessel pit was Fagus crenata var. multinervis and species with oval ray-vessel pit were Q, dentata, Castanopsis cuspidata var sieboldii.

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Accurate Measurements of the Unloaded Q of a Dielectric-loaded High-Q $TE_{01{\delta}}$ mode Cavity Resonator with HTS Endplates

  • Kwon, H.J.;Hur, Jung;Lee, Sang-Young
    • Progress in Superconductivity
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    • 제1권1호
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    • pp.36-41
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    • 1999
  • Methods for mode identification and accurate measurements of the unloaded Q ($Q_0$) of a dielectric-loaded $TE_{01{\delta}}$ mode cavity resonator with HTS endplates are proposed. A resonator with a sapphire rod and $YBa_2Cu_3O_{7-x}$(YBCO) endplates was prepared and its microwave properties were studied at temperatures above 30 K. The $TE_{01{\delta}}$ mode $Q_0$ of the resonator, designed to work as a tunable resonator with variations in the gap distance (s) between the sapphire rod and the top YBCO, was more than 1000000 at s = 0 mm and at 30 K with the resonant frequency of 19.56 GHz. The $TE_{01{\delta}}$ mode $Q_0$ decreases as s increases for s < 2 mm until mode couplings between the $TE_{01{\delta}}$ mode and other modes appeared at s = 2 mm. Significant dependence of the $TE_{01{\delta}}$ mode $Q_0$ on the input and output coupling constants was also observed. Applications of the open-ended $TE_{01{\delta}}$ mode cavity resonator for a tunable resonator with a very high Q as well as a characterization tool for the surface resistance measurements of HTS films are described.

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MORE EXPANSION FORMULAS FOR q, 𝜔-APOSTOL BERNOULLI AND EULER POLYNOMIALS

  • Ernst, Thomas
    • 대한수학회논문집
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    • 제35권2호
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    • pp.417-445
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    • 2020
  • The purpose of this article is to continue the study of q, 𝜔-special functions in the spirit of Wolfgang Hahn from the previous papers by Annaby et al. and Varma et al., with emphasis on q, 𝜔-Apostol Bernoulli and Euler polynomials, Ward-𝜔 numbers and multiple q, 𝜔power sums. Like before, the q, 𝜔-module for the alphabet of q, 𝜔-real numbers plays a crucial role, as well as the q, 𝜔-rational numbers and the Ward-𝜔 numbers. There are many more formulas of this type, and the deep symmetric structure of these formulas is described in detail.

강화 학습에서의 탐색과 이용의 균형을 통한 범용적 온라인 Q-학습이 적용된 에이전트의 구현 (Implementation of the Agent using Universal On-line Q-learning by Balancing Exploration and Exploitation in Reinforcement Learning)

  • 박찬건;양성봉
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제30권7_8호
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    • pp.672-680
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    • 2003
  • shopbot이란 온라인상의 판매자로부터 상품에 대한 가격과 품질에 관한 정보를 자동적으로 수집함으로써 소비자의 만족을 최대화하는 소프트웨어 에이전트이다 이러한 shopbot에 대응해서 인터넷상의 판매자들은 그들에게 최대의 이익을 가져다 줄 수 있는 에이전트인 pricebot을 필요로 할 것이다. 본 논문에서는 pricebot의 가격결정 알고리즘으로 비 모델 강화 학습(model-free reinforcement learning) 방법중의 하나인 Q-학습(Q-learning)을 사용한다. Q-학습된 에이전트는 근시안적인 최적(myopically optimal 또는 myoptimal) 가격 결정 전략을 사용하는 에이전트에 비해 이익을 증가시키고 주기적 가격 전쟁(cyclic price war)을 감소시킬 수 있다. Q-학습 과정 중 Q-학습의 수렴을 위해 일련의 상태-행동(state-action)을 선택하는 것이 필요하다. 이러한 선택을 위해 균일 임의 선택방법 (Uniform Random Selection, URS)이 사용될 경우 최적 값의 수렴을 위해서 Q-테이블을 접근하는 회수가 크게 증가한다. 따라서 URS는 실 세계 환경에서의 범용적인 온라인 학습에는 부적절하다. 이와 같은 현상은 URS가 최적의 정책에 대한 이용(exploitation)의 불확실성을 반영하기 때문에 발생하게 된다. 이에 본 논문에서는 보조 마르코프 프로세스(auxiliary Markov process)와 원형 마르코프 프로세스(original Markov process)로 구성되는 혼합 비정적 정책 (Mixed Nonstationary Policy, MNP)을 제안한다. MNP가 적용된 Q-학습 에이전트는 original controlled process의 실행 시에 Q-학습에 의해 결정되는 stationary greedy 정책을 사용하여 학습함으로써 auxiliary Markov process와 original controlled process에 의해 평가 측정된 최적 정책에 대해 1의 확률로 exploitation이 이루어질 수 있도록 하여, URS에서 발생하는 최적 정책을 위한 exploitation의 불확실성의 문제를 해결하게 된다. 다양한 실험 결과 본 논문에서 제한한 방식이 URS 보다 평균적으로 약 2.6배 빠르게 최적 Q-값에 수렴하여 MNP가 적용된 Q-학습 에이전트가 범용적인 온라인 Q-학습이 가능함을 보였다.

2002~2016년도 제주도 소아의 성홍열 발생의 시계열분석 (Time series analysis for incidence of scarlet fever in children in Jeju Province, Korea, 2002~2016)

  • 신인혜;배종면
    • Journal of Medicine and Life Science
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    • 제16권3호
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    • pp.90-95
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    • 2019
  • The Korea Centers for Diseases Control and Prevention interpreted that recent outbreaks of scarlet fever in Korea since 2011 was resulted from the expansion of scarlet fever notification criteria. To suggest a relevant hypothesis regarding this emerging outbreak, a time series analysis(TSA) of scarlet fever incidence between 2002 and 2016 was conducted. The raw data was the nationwide insurance claims database administered by the Korean National Health Insurance Service. The inclusion criteria were children aged ≤14 years residing in Jeju Province, Korea who received any form of healthcare for scarlet fever from 2002 to 2016. The season was defined as winter (December, January, February; Q1), spring (March, April, May; Q2), summer (June, July, August; Q3), and autumn (September, October, November; Q4). There were seasonal variations with showing peak season on Q1 and Q3. And three phases as 2002 Q2~2005 Q2, 2005 Q2~2009 Q4, and 2010 Q1~2016 Q4 were found between 2002 and 2016. The results from TSA suggested that the recent outbreak of scarlet fever among children in Jeju Province might be a phenomenon from 'unknown birth-related environmental factors' changed after 2010.

Aberrant Epigenetic Alteration in Eca9706 Cells Modulated by Nanoliposomal Quercetin Combined with Butyrate Mediated via Epigenetic-NF-κB Signaling

  • Zheng, Nai-Gang;Wang, Jun-Ling;Yang, Sheng-Li;Wu, Jing-Lan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권11호
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    • pp.4539-4543
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    • 2014
  • Since the epigenetic alteration in tumor cells can be reversed by the dietary polyphenol quercetin (Q) or butyrate (B) with chemopreventive activity, suggesting that Q or B can be used for chemopreventive as well as therapeutic agent against tumors. In this study the polyphenol flavonoid quercetin (Q) or sodium butyrate (B) suppressed human esophageal 9706 cancer cell growth in dose dependent manner, and Q combined with B (Q+B) could further inhibit Eca9706 cell proliferation than that induced by Q or B alone, compared with untreated control group (C) in MTT assay. The reverse expressions of global DNMT1, $NF-{\kappa}Bp65$, HDAC1 and Cyclin D1 were down-regulated, while expressions of caspase-3 and $p16INK4{\alpha}$ were up-regulated, compared with the C group in immunoblotting; the down-regulated HDAC1-IR (-immunoreactivity) with nuclear translocation, and up-regulated E-cadherin-IR demonstrated in immunocytochemistry treated by Q or B, and Q+B also displayed further negatively and positively modulated effects compared with C group. The order of methylation specific (MS) PCR of $p16INK4{\alpha}$: C>B/Q>Q+B group, while the order of E-cadherin expression level was contrary, Q+B>Q/B>C group. Thus, Q/B, especially Q+B display reverse effect targeting both altered DNA methylation and histone acetylation, acting as histone deacetylase inhibitor mediated via epigenetic-$NF-{\kappa}B$ cascade signaling.

수종 참나무속 유식물의 건조스트레스에 대한 기공저항의 조절과 전략의 분화 (Stomatal Control and Strategy Segregation to Drought Stress in Young Trees of Several Oak Species)

  • 김종욱;김준호
    • The Korean Journal of Ecology
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    • 제17권3호
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    • pp.241-249
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    • 1994
  • 참나무속 식물 6종류의 잎의 확산저항, 기공밀도, 공변세포의 길이 및 털의 밀도를 측정하여 건조스트레스에 대한 이 식물들의 전략을 주성분분석법으로 분석하였다. 상수리나무, 갈참나무 및 졸참나무의 잎의 확산저항은 다른 3종보다 높은 Ψleaf 또는 낮은 WSD에서 빠르게 상승함으로써 수분 스트레스를 회피하였다. 그러나, 신갈나무와 떡갈나무는 낮은 Ψleaf, 낮은 기공밀도, 작은 기공 크기 및 높은 털밀도로 수분스트레스를 회피하였다. 그러나 신갈나무와 떡갈나무는 낮은 Ψleaf에서 기공 확산저항의 상승을 보였다. 건조스트레스에 대한 조정능과 관련된 15변수의 주성분분석에서 참나무속 식물은 2그룹, 즉 건성생육지종인 굴참나무, 신갈나무 및 떡갈나무와 중성생육지종인 상수리 나무, 갈참나무 및 졸참나무로 구별되었고, 건성생육지종인 굴참나무는 높은 털밀도, 낮은 기공밀도 및 높은 LAR에서 신갈나무 및 떡갈나무와 다시 구별되었다. 이 결과는 자연생육지에서 참나무속 식물의 건조에 대한 전략을 잘 설명하고 있다.

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방사선과 대학생이 지각하는 방사선사의 이미지에 관한 Q방법론적 융합 연구 (A Q-Methodological Convergence Study on Images of Radiologists as Perceived by Radiology College Students)

  • 김영란;서선열;전민철
    • 한국융합학회논문지
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    • 제10권12호
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    • pp.143-149
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    • 2019
  • 방사선사의 이미지는 방사선과 대학생의 전문직관 확립과 방사선사직의 수행에 영향을 준다. 따라서 본 연구는 방사선과 대학생을 대상으로 방사선사의 이미지에 대한 유형을 파악하기 위해 Q방법론을 이용하였다. Q 모집단은 W대학교, D대학교 방사선과 학생 110명으로 이들로부터 총 110개의 Q 표본인 방사선사의 이미지에 대한 진술문을 수집하였다. 선택된 진술문은 전문가의 검토와 수정절차를 거쳐 최종적으로 33개의 Q표본을 선정하였다. 33개의 Q 표본을 바탕으로 방사선과 대학생 30명이 9점 척도로 등급을 매겼다. 자료분석은 PQ method Program을 이용하였다. 연구결과 방사선사의 이미지에 대한 인식 유형으로 '전문기술형', '환자안전형'의 두 가지 유형으로 도출되었다. 본 연구는 방사선과 대학생이 인식하고 있는 방사선사의 이미지 유형을 이해하고, 앞으로 방사선사의 교육과정과 방사선사의 정책방안에 기초자료로 활용될 수 있다.