天然闊葉樹林內 主要 構成 樹種의 天然更新 樣相

金知洪,梁熙文,金光澤,李元燮,姜聲基 강원대학교 삼림과학연구소 2001 Journal of Forest Science Vol.17 No.-

이 연구는 "국유림 경영 현대화 산학 협동 실연 연구"의 일환으로 강원도 평창군 가리왕산 일대 천연활엽수림을 대상으로, 주요 수종별 천연갱신 특성을 평가하여 연구대상 산림의 전반적인 천연갱신에 대한 종합적인 생태적 정보를 제공하고자 실시되었다. 수종별 천연갱신 특성을 요약하면 다음과 같다. 거제수나무 : 비산되는 종자이므로 종자 공급에는 문제가 없으나, 종자 발아를 위해서 노출된 광물질토양이 필요하며, 두꺼운 낙엽층은 종자 발아를 제한한다. 발아 후 갱신치수는 다량의 광선을 필요로 한다. 고로쇠나무 : 내음성은 강하나, 치수의 내건성이 약하므로 50% 이상의 피음을 요구하며, 우량 형질의 임목 조성을 위해 높은 초기 밀도를 유지하여야 한다. 맹아정신력은 높다. 난티나무 : 수분 요구도가 높고 내음성이 약하므로 60% 가량의 상층 울폐도를 유지하여 보습과 광선유입이 원활하여야 하며, 치수 활착을 위해서 관목류 및 기타 식생으로부터 경쟁 요인을 제거한다. 들메나무 : 종자 발아를 위해 광물질 토양의 노출이 필수적이며, 치수 활착을 위해서 다량의 수분과 광선이 요구되고, 지피식생에 의한 치수의 피압이 우려되므로 임지정리작업 도입이 필수적이다. 물푸레나무 : 종자 결실의 풍흉이 심하며, 두꺼운 낙엽층은 종자발아를 제한한다. 치수 활착시 지피식생에 의한 피압이 우려되므로 임지정리작업의 도입이 필수적이다. 신갈나무 종자공급의 문제(설치류에 의한 피해) 및 두꺼운 낙엽층 및 조릿대 밀생 지역에서는 종자발아가 제한되며, 치수 발생 후, 임관의 50% 이상을 열어줄 필요가 있고, 맹아갱신력이 높다. 음나무 : 두꺼운 낙엽층은 종자발아를 제한하며, 유령목 생육에 다량의 광선이 요구된다. 젓나무 : 내음성은 강하나, 유령목 단계에서 생육은 극히 저조하다. 층층나무 : 동물에 의해서 종자가 산포되지만 종자 피해는 불가피하며, 발아와 치수 활착을 위해서 단량의 광선이 요구된다. 피나무 : 종자 충실률이 낮고 이중 휴면성 때문에 종자 공급에 어려움이 있으며, 두꺼운 낙엽층은 종자발아의 걸림이 되므로 광물질 토양이 필요하고, 맹아갱신력이 매우 높다. Forming a part of "Cooperative Practical Study for the Modernization of the Management of National Forest", this study was conducted to provide overall ecological information for the natural regeneration of major tree species on the basis of community structural attributes in the deciduous forest ecosystem. Followings are summarized characteristics of the natural regeneration for the selected tree species. Betula costata : Although large number of seeds are dispersed by wind, they require mineral soils to germinate. Thick litter layer could be an obstacle to germinate. After germination, the seedling requires large amount of light for successful establishment. Acer mono : Characterized by high shade tolerance and weak drought resistance, the seedling should be overcasted with more than 50% of canopy coverage. High stand density should be maintained to produce good quality of timber. The potential of coppice may be high. Ulmus laciniata : Since this species needs high rate of troll moisture and light, around 60% of canopy coverage should be maintained to retain moisture and incoming light. The competition with other vegetation should be removed for the favor of successful seedling establishment. Fraxinus mandshurica : This species requires moist mineral soils to germinate. After germination, the seedling needs large amount of light and moisture for successful establishment. Site preparation should be applied to reduce competition with weedy vegetation. Fraxinus rhynchophylla : Interval of large seed crops may be highly varied. Thick litter layer could be an obstacle to germinate. Site preparation should be applied to reduce competition with weedy vegetation so as to achieve successful seedling establishment Quercus mongolica : Including the difficulty of seed supply by the consumption, thick litter layer and mountain bamboo cover could be the obstacle to germinate. More than 50% of relative light intensity is necessary to achieve successful seedling establishment. Kalopanax pictus : Thick litter layer could be an obstacle to germinate. The seedling needs large amount of light and moisture for successful establishment. Abies holophylla : In spite of high shade tolerance, the growth rate in sapling stage may be extremely slow. Cornus controversa : Seeds (drups) are consumed and dispersed by animals, tending to be not sufficient in seed supply. This species requires large amount of light for successful germination and seedling establishment. Tilia amurensis : The difficulty of seed supply might be expected with low seed purity and double dormancy. Since thick litter layer could be an obstacle to germinate, the species requires moist mineral soils for successful germination. The potential of coppice may be extremely high. Key words : natural deciduous forest, natural regeneration microtopography

點鳳山一帶 天然闊葉樹林의 地形的 位置에 따른 群集 構造的 屬性 分析(Ⅰ) : 樹種構性, 種多樣性, 生活型을 中心으로

姜聲基,金知洪,金光澤,梁熙文 강원대학교 삼림과학연구소 2000 Journal of Forest Science Vol.16 No.-

이 연구는 점봉산 일대 천연활엽수림을 대상으로 산림의 지형적 위치에 따라 군집의 구조적 속성이 달라진다는 가정하에 대상산림을 계곡, 산복, 능선으로 구분하고 각 군집별 수종구성, 종다양성, 생활형 분석을 통해 산림 생태계의 군집 속성을 파악하여 산림경영의 생태적 접근 방안을 위한 기초자료를 제공하고자 실시 되었다. 연구 결과, 계곡지역 상층의 수종구성은 신갈나무, 전나무, 들메나무 순으로 우점하고 있는 것으로 나타났고, 산복지역에서는 피나무, 신갈나무, 가래나무 순으로 나타났으며, 능선지역에서는 신갈나무, 피나무, 물푸레나무 순으로 나타났다. 그러나 중층과 하층에서 높은 우점률을 보이는 까치박달과 당단풍은 생육특성상 상층목으로의 도약을 기대하기 어려울 것으로 추정되었다. 종다양성은 계곡, 산복, 능선등 모든 지역의 중층과 하층에서는 유사한 것으로 파악되었으나, 상층에서는 능선지역이 계곡과 산복지역에 비해 매우 낮게 나타났다. 그리고 수분조건이 좋은 계곡보다 산복지역이 종다양성이 높은 것으로 파악되었다. 조사된 146종의 관속식물을 대상으로 생활형을 휴면형을 기준으로 구분한 결과, 지중식물, 교목, 반지중식물, 아교목, 관목, 1년생식물, 지표식물, 수생식물 순으로 나타났다. 특히 희귀 및 멸종식물로 지정된 금강초롱꽃은 본 연구 대상지 전역에서 쉽게 관찰되었다. Taking account of the structural variation on species composition according to the different topographic positions, i.e. valley, mid-slope, and ridge, the species composition, species diversity, life tool·m were comparatively analyzed fort· the three topographic positions in the natural deciduous forest of Mt. Chumbong area. The results are as follows. 1.Specise Composition : Dominant species in the overstory were Quercus mongolica. Abies holophylla, and Fraxinus mandshurica in valley ; Tilia amuresis, Quercus mongolica, and Juglans mandshurica in mid-slope ; and Quercus mongolica, Tilia amurensis, and Fraxinus rhynchophylla in ridge. Acer p. and Carpinus c. which have maintained high composition ratio in mid-story were not considered to be dominant overstory species due to inherent growth form. 2.Species Diversity : The species diversity indices of mid- and understory showed not much different value in three topographic positions. However, the index of overstory in ridge had smaller value than those of valley and mid-slope. The stand in ridge had greater species diversity index than in valley where moisture condition could be more favorable. 3.Life Form : The total of 146 vascular were observed in Mt. Chumbong in this study Especially, Hanabusaya asiatica Nakai, were supposed to be the rare and endangered species, was easily found in many places. The proportion of life form spectra in the study forest was G-MM-H-N-Th-Ch-HH. Key words : natural deciduous forest, species composition, species diversity, life form.

An effective route for the fabrication of multi-walled carbon nanotubes-reinforced ROMP-based nanocomposites by solution casting technique

Yang, Guang,Yan, Jing,Jeong, Young Gyu,Lee, Jong Keun Elsevier Science Ltd 2017 Composites Applied science and manufacturing Vol. No.

<P><B>Abstract</B></P> <P>This work reports the solvent-soluble multi-walled carbon nanotubes (MWCNTs), which can be used for the fabrication of ring-opening metathesis polymerization (ROMP)-based nanocomposites by solution casting technique. As the first and most important step of the solution casting technique, the excellent dispersibility of the MWCNTs in different solvents is achieved by the functionalization of the nanotube surface with norbornene oligomers. The norbornene-functionalized MWCNTs (nMWCNTs) have outstanding dispersion stability in water, tetrahydrofuran (THF), acetone, and ethanol, especially the maximum nanotube concentration of 3.9mg/mL in THF. The incorporation of nMWCNTs into poly(5-ethylidene-2-norbornene) (poly(ENB)) by solution casting technique results in significant improvements in the mechanical properties over the neat poly(ENB) and the pristine MWCNT-reinforced poly(ENB) nanocomposites. The route developed here not only avoids the dramatic increase of the viscosity occurring in the bulk polymerization but also provides the feasibility of high loadings of MWCNT reinforcements, consequently broadening the potential applications of ROMP-based nanocomposites.</P>

Collaborative Sub-channel Allocation with Power Control in Small Cell Networks

( Guang Yang ),( Yewen Cao ),( Deqiang Wang ),( Jian Xu ),( Changlei Wu ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.2

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

SDN‐Based Hierarchical Agglomerative Clustering Algorithm for Interference Mitigation in Ultra‐Dense Small Cell Networks

Guang Yang,Yewen Cao,Amir Esmailpour,Deqiang Wang 한국전자통신연구원 2018 ETRI Journal Vol.40 No.2

Ultra‐dense small cell networks (UD‐SCNs) have been identified as a promising scheme for next‐generation wireless networks capable of meeting the ever‐increasing demand for higher transmission rates and better quality of service. However, UD‐SCNs will inevitably suffer from severe interference among the small cell base stations, which will lower their spectral efficiency. In this paper, we propose a software‐defined networking (SDN)‐based hierarchical agglomerative clustering (SDN‐HAC) framework, which leverages SDN to centrally control all sub‐channels in the network, and decides on cluster merging using a similarity criterion based on a suitability function. We evaluate the proposed algorithm through simulation. The obtained results show that the proposed algorithm performs well and improves system payoff by 18.19% and 436.34% when compared with the traditional network architecture algorithms and non‐cooperative scenarios, respectively.

SNPs of Excision Repair Cross Complementing Group 5 and Gastric Cancer Risk in Chinese Populations

Yang, Wan-Guang,Zhang, Shan-Feng,Chen, Ju-Wu,Li, Li,Wang, Wan-Peng,Zhang, Xie-Fu Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

We conducted a case-control study to determine the association between several potential SNPs of excision repair cross complementing group 5 (XPG) and gastric cancer susceptibility, and roles of XPG polymorphisms in combination with H.pylori infection in determining risk of gastric cancer. In our study, we collected 337 newly diagnosed gastric cancer cases and 347 health controls. Three SNPs of XPG, rs2296147T>C, rs2094258C>T and rs873601G>A, were genotyped using the Taqman real-time PCR method with a 7900 HT sequence detector system. H. pylori infection was diagnosed by ELISA. By multivariate logistic regression analysis, the rs2296147 CC genotype was associated with a decreased risk of gastric cancer (OR=0.52, 95% CI=0.27-0.97), and rs2094258 TT was associated with elevated risk (OR=2.13, 95% CI=1.22-3.35). Positive H.pylori individuals with rs2094258 TT genotypes demonstrated increased risk of gastric cancer (OR=2.13, 95% CI=1.22-3.35), while rs2296147 CC was associated with lower risk among patients with negative H.pylori (OR=0.45, 95%CI=0.22-0.89). Our findings suggested that XPG polymorphisms might contribute to risk of gastric cancer among Chinese populations, but the effect needs to be further validated by larger sample size studies.

A simulant study of the Network of Five Elements by using the computer

Yang, jian hua,Zhang, zhi guang,Zhang, guang nian,Lin, Shu huang 한국정신과학학회 1997 한국정신과학회 학술대회 논문집 Vol.7 No.-

The theory of Chinese medicine is a based theory to research the paranomarl function of human body including ESP and PK etc. The theory of the traditional Chinese medicine indictes that the life prosesses can be discribed by the system of five elements (SFE), which are: wood, fire, earth, metal and water. We take the SFE for a network consisted of this five elements (NFE), and study the characteries of the structure of this NFE. they include multi-cross character; directiong and irreversible character; mesomerism character; "open" character and Fuzzy character etc. Then, based on these characters, we simulate the partial function of NFE by using computer. The results of simulation show that the NFE is a very useful network to explain the physiological and pathological phenomenan of human body according to the theory of traditional Chinese medicine.

Development of gradient composite shielding material for shielding neutrons and gamma ray

Guang Hu,Guang Shi,Huasi Hu,Quanzhan Yang,Bo Yu,Weiqiang Sun 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.10

In this study, a gradient material for shielding neutrons and gamma rays was developed, which consists of epoxy resin, boron carbide (B4C), lead (Pb) and a little graphene oxide. It aims light weight and compact, which will be applied on the transportable nuclear reactor. The material is made up of sixteen layers, and the thickness and components of each layer were designed by genetic algorithm (GA) combined with Monte Carlo N Particle Transport (MCNP). In the experiment, the viscosities of the epoxy at different temperatures were tested, and the settlement regularity of Pb particles and B4C particles in the epoxy was simulated by matlab software. The material was manufactured at 25 °C, the Pb C and O elements of which were also tested, and the result was compared with the outcome of the simulation. Finally, the material's shielding performance was simulated by MCNP and compared with the uniformity material's. The result shows that the shielding performance of gradient material is more effective than that of the uniformity material, and the difference is most noticeable when the materials are 30 cm thick.

Isoindolin-1-ones from the stems of Nicotiana tabacum and their antiviral activities

Guang-Yu Yang,Jia-Meng Dai,Zhen-Jie Li,Jin Wang,Feng-Xian Yang,Xin Liu,Jing Li,Qian Gao,Xue-Mei Li,Yin-Ke Li,Wei-Guang Wang,Min Zhou,Qiu-Fen Hu 대한약학회 2022 Archives of Pharmacal Research Vol.45 No.8

In previous studies, several isoindolin-1-oneanalogs that exhibited signifi cant anti-tobacco mosaic virus(anti-TMV) activities were isolated from Nicotiana tabacum . Since gene-editing mutants provide a new sample for thediscovery of active metabolites, we focused on the stems ofYN-18–23 (a mutant N. tabacum for gene editing with thealkaloid metabolic pathway cultivated by Yunnan TobaccoCompany), which led to the isolation of four new ( 1–4 )and four known ( 5–8 ) isoindolin-1-ones. To the best of ourknowledge, nicindole C ( 3 ) is the fi rst subclass of isoindolin-1-one bearing a pentacyclic ketone, while nicindole D ( 4 )is the fi rst example of isoindolin-1-one bearing a methylpyridin-2-(1 H )-one moiety. Compounds 1–4 were testedfor their anti-TMV activities, and the results revealed thatcompounds 1 , 3 , and 4 exhibited high anti-TMV activities atconcentrations of 20 μM with inhibition rates of 48.6, 42.8,and 71.5%, respectively. These rates are higher than the inhibitionrate of the positive control (33.2%). The mechanisticstudy of compound 4 , which had the highest anti-TMV activityrevealed that increased potentiation of defense-related enzyme activities and downregulation of expression of theNtHsp70 protein may induce resistance in tobacco againstthe viral pathogen TMV. Molecular docking studies alsorevealed that the isoindolin-1-one substructure is fundamentalfor anti-TMV activity. The methyl-pyridin-2-(1 H )-onemoiety in compound 4 and the 2-oxopropyl groups in compounds1 and 3 at the N -2 position may increase inhibitoryactivities. This study of the structure–activity relationshipis helpful for fi nding new anti-TMV activity inhibitors. Tostudy whether the isoindolin-1-ones have broader antiviralactivities, compounds 1–4 were also tested for their antirotavirusactivities. Compound 4 exhibited high anti-rotavirusactivity with a therapeutic index (TI) value of 20.7. This TI value is close to that of the positive control (20.2).

Nuclear Power Plant Security and Counter-Terrorist Strategy

YANG Guang,HUANG WenJie,LEI Linli 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

Nuclear power plants have long been recognized as potential targets of terrorist attacks Given the potentially catastrophic consequences of deliberate act on nuclear power plant and energy security issue followed, nuclear power plant security is elevated to a world-wide security concern. This paper focuses attention on security and vulnerability intrinsic of nuclear power plant. Firstly, the present paper summarizes the attack mode and types of terrorist, and it analyzes the defence in depth, design basis threat, target set, vulnerability from air attack, used fuel storage and risk of nuclear transports. In the end, the counter terrorist proposals are also presented and some of them are proved valid in practice in western nations, However, with the attack means constantly upgrading, more insufficiency of design being revealed, more sophisticated defensive system should be developed.