• 한국안전학회지
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• 제32권5호
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• pp.149-156
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• 2017

This study investigates fire-retardant performances and combustion/thermal characteristics of fire-retardant treated wood by comparing them with those of fire-retardant untreated wood from the expreimental resutls of cone calorimeter and thermo-gravimetric(TG) analyzer. Hazardousness of combustion product gases for fire-retardant treated wood and untreasted wood were also observed from the results of internal finish material incombustibility test according to the Korea standard code of KS F 2271. In this study, we also tried to improve the fire retardant performance of wood by applying fire-retardant chemical composites, and to secure the fire safety performance in buildings. Red pine (Pinus densiflora) was selected as a test specimen because it is mostly used as a building material in Korea. Fire retardant chemical composites (FRCs) were prepared by mixing boron, phosphorous, and nitrogen species and treated by press-impregnation method. Water-based FRCs were composed of 3% boric acid($H_3BO_3$), 3% borax decahydrate($Na_2B_4O_7$), 8% ammonium carbonate($(NH_4)_2CO_3$), diammonium phosphate ($(NH_4)_2HPO_4$) varied from 10-30% and potassium carbonate($K_2CO_3$) varied from 10-30%. From the test results of cone calorimeter, TG analysis and gas hazard assessments, newly proposed were the optimal composition and production methods of FRCs which can sufficiently meet fire-retardant level 3 based on Korea law of construction. Thus, the FRCs, developed in this study, are anticipated to contribute to the improvement of fire safety and widespread of usage in wood as building materials.

• Journal of the Korean Wood Science and Technology
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• 제29권3호
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• pp.14-20
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• 2001

On the bending process, metal-strap plays an important role in dispersing the stress generated in wood. Therefore, the metal-strap has more influence on the property of bentwood materials. The effect of the metal-strap thickness for bentwood was examined. The effect of metal-strap on the bending properties of Korean red pine(Pinus densiflora Sieb. et Zucc.)was investigated in this research. The metal-strap thickness is divided into 4 kinds such as 1.0, 0.8, 0.6, 0.4 mm. The specimens were selected by grain such as annual ring angles, flat grain and half-edge grain specimens. As a result of this study, the bending ability of 1.0, 0.8 mm, thickness of half-edge grain specimens was better than flat grain specimens but the result of 0.6, 0.4 mm were reversed. The bending ability of half-edge grain was better than flat grain and the grade was higher. When the processed specimens were dried, the radius of curvature(ROC) was decreased became drying-stress was not perfectly dispersed. An optimum drying-condition would deminish this phenomenon.

• 한국조경학회지
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• 제32권4호
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• pp.28-38
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• 2004

Korean goral (Nemorhaedus caudatus raddeanus) is one of the endangered species in Korea, and the rugged terrain of the Soraksan National Park (373㎢) is a critical habitat for the species. But the goral population is threatened by habitat fragmentation caused by roads and hiking trails. The objective of this study was to develop a potential habitat suitability model for Korean goral in the park, and the model was based on the concepts of fuzzy set theory and multi-criteria evaluation. The process of the suitability modeling could be divided into three steps. First, data for the modeling was collected by using field work and a literature survey. Collected data included 204 points of GPS data obtained through a goral trace survey and through the number of daily visitors to each hiking trail during the peak season of the park. Second, fuzzy set theory was employed for building a GIS data base related to environmental factors affecting the suitability of the goral habitat. Finally, a multiple-criteria evaluation was performed as the final step towards a goral habitat suitability model. The results of the study were as follows. First, characteristics of suitable habitats were the proximity to rock cliffs, scattered pine (Pinus densiflora) patches, ridges, the elevation of 700∼800m, and the aspect of south and southeast. Second, the habitat suitability model had a high classification accuracy of 93.9％ for the analysis site, and 95.7％ for the validation site at a cut off value of 0.5. Finally, 11.7％ of habitatwith more than 0.5 of habitat suitability index was affected by roads and hiking trails in the park.

• Journal of Plant Biology
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• 제11권4호
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• pp.9-20
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• 1968

In general there are few cases which were caused by lightening and no fire was observed to have been caused but by artificial or accidental fires during preliminary survey. And then the most scales of burning in Korea are like the fig. 2. Temperature 5 cm apart from flame at the burning site were known to range from 165$^{\circ}$to 20$0^{\circ}C$ in surface fire on Myozangdong, pine-quercus dominant community and from 120$^{\circ}$ to 145$^{\circ}C$ in surface fire of Wolwoonni, Mischanthus dominant area and from 120$^{\circ}$ to 14$0^{\circ}C$ in ground fire of Wangzinkun, Mischanthus dominant, respectively. Through the preliminary survey, fire indicater plants in Korea were confirmed as Mischanthus coreensis Hack and Carex alterifolia Franch. The plants of highest frequency appeared in the burnt sites were known to as Potentilla cryptotaeniae Max, Mischanthus coreensis Hack, Carex alterifolia Franch and Artemisia brachyphylla Kitamura. Lespedezas were proved as one of the fire tolerant and Pinus densiflora was found out as the lowest intolerant plant to fire. The acidity of burnt soil was decreased according to the considerable amount of ash left on the ground. The acidity of surface soil was more decreased than the below 10cm of soil. The chemical composition(NO3, P, K, Mg, Total-N and Organic-C) of burnt soil was more increased than those of the unburnt sites. And the population changes of soil microflora seemed to have a certain tendency. The population of soil microflora was increased a little according to climatic conditions. Also there was an initial decrease in the population of microflora followed immediately by a significant increase.

• 한국자원식물학회지
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• 제25권1호
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• pp.63-71
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• 2012

To assess parameters of mating system in seed orchard, such as outcrossing rates, number of potential pollen contributors, and degree of pollen contamination, seeds, produced in '77 plot of the Japanese red pine (Pinus densiflora S et Z) seed orchard at Anmyeon island, were collected in 2007 and analysed by nSSR and cpSSR markers. Estimates of outcrossing rates ranged from 91.2 to 100% (mean 97.7%) on the basis of the analysis of cpSSR haplotypes and from 81.6 to 100% (mean 95.3%) on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, seeds, presumed to be products of self pollination on the basis of single marker, were confirmed as outcrossed seeds, which resulted in cumulative outcrossing rates of 98.9%. On the basis of pooled cpSSR haplotype of each seed, the number of pollen contributors and paternal contribution rates were estimated as 14.8 and 0.512, respectively. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, good genetic potential of the seeds, produced in '77 plot of the seed orchard of Japanese red pines at Anmyeon island, may be guaranteed. Investigated results from the analysis of mating system of Japanese red pines in a '77 plot of the seed orchard may also be expected to provide useful information for the management and establishment of the seed orchard of the progressive generation.

• The Plant Pathology Journal
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• 제23권1호
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• pp.7-12
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• 2007

Perilla rust is a damaging disease in perilla cultivation in Korea. Its causal agent was identified as Coleosporium plectranthi based on descriptions of morphological characteristics of spores and spore-producing fruiting structures(in uredinial and telial stages from perilla and in aecial stage from the alternate host pine) collected in 15 locations in Korea during the disease survey from 2004 to 2006. These characteristics were yellow or orange uredinium; globose or ellipsoid urediniospore of $20.8{\mu}m{\times}18{\mu}m$ in size; verruca of $0.3mm{\times}1.2mm$; orange telium; one-celled, oblong ellipsoid teliospore of $63.1{\mu}m{\times}19.7{\mu}m$ with one-layered crusts or four-celled(when mature), internal basidium of $64.2{\mu}m{\times}19.7{\mu}m$; ellipsoid to globoid basidiospore of $20.3{\mu}m{\times}12{\mu}m$; type 2 spermogonium; yellow, broadly ellipsoid peridial cell of $35.6{\mu}m{\times}23.1{\mu}m$; and broadly ellipsoidal or subglobose aeciospore of $25.9{\mu}m{\times}18.8{\mu}m$. Phylogenetic analysis of 28S rDNA sequences revealed the closest relatedness to those of the genus Coleosporium, a monophyletic group distinguished from other rust fungi and divided into two main lineages, one of which was C. plectranthi grouped with high bootstrap value(96%). In pathogenicity test, both aeciospores and urediniospores caused rust development on perilla leaves. This is the first description of C. plectranthi causing perilla rust with the first findings of its telial stage on perilla and the first rust disease on the aecial host in Pinus densiflora. These aspects would provide basic information for the development of control measures of the disease.

• Journal of the Korean Wood Science and Technology
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• 제28권2호
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• pp.3-9
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• 2000

투습조건이 다른 경우에 있어서, 목재의 두께를 동일하게 하여 목재내부의 함수율분포 및 함수율의존성을 조사하였다. 시험편은 소나무재로 직경 70mm, 두께 20mm 인 정목판재를 이용하였다. 실험은 JIS Z-0208규정에 의거하여 10가지 종류를 선정하여 실시하였다. 목재내 함수율분포는 함수율 10%위치를 경계로 두 개의 직선으로 나타났다. 한편, 10%보다 높거나 낮을때는 한 개의 직선으로 나타났다. 따라서 함수율 10%값은 목재나 실험조건과는 상관없이 나타나는 것으로 생각되었다. 10%는 수분흡착에너지가 변화하는 경계점으로 추정되었다. 전보에서 일정한 실험조건에서는 목재의 두께에 상관없이 일정한 값을 나타내었지만, 본 연구에서 확산계수는 실험조건에 따라 수분경사로 구한 확산계수는 목재함수율에 따라 다양하게 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제49권4호
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• pp.384-393
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• 2021

Recently, due to environmental and toxicity issues, there has been increasing attention on research regarding natural products that can reduce the use of chemical fertilizers. Wood extracts derived from the biorefining process contain various fertilizer ingredients. HPLC analysis revealed that wood extract contains approximately 5.2% hemicellulosic sugar. The growth of lettuce (Lactuca sativa) upon treatment with wood extract (extract obtained from steam-exploded pine) or water-soluble fertilizers containing different nutrients was analyzed in this study. After two weeks, the growth characteristics of lettuce as affected by wood extract or water-soluble fertilizers were significantly different. The effect of water-soluble fertilizers containing ascorbic acid, magnesium sulfate, citric acid, potassium nitrate, amino acids, or seaweed extract was less desirable than that of wood extracts regarding plant height (18.6 cm), number of leaves (10), leaf length (14.1 cm), shoot fresh wight (9.8 g/plant), root fresh weight (0.8 g/plant) and shoot dry weight (0.6 g/plant). The plant height, number of leaves, leaf length, shoot fresh wight, root fresh weight, shoot dry weight of water-soluble fertilizers containing wood extract were significantly different compared to the control (plant height :13.5 cm, number of leaves : 7, leaf length : 9.4 cm, shoot fresh wight : 5.3 g/plant, root fresh weight : 0.7 g/plant, shoot dry weight : 0.4 g/plant, root dry weight : 0.07 g/plant). From these results, it was concluded that wood extract can be used as a potential water-soluble fertilizer to increase the yield of leafy vegetables.

• Journal of the Korean Wood Science and Technology
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• 제31권4호
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• pp.44-49
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• 2003

수용성 방부처리(AAC, CCA-3, ACQ, CuAz) 소나무 시편의 기상열화에 대한 저항성을 평가하기 위하여 인공촉진열화 방법을 사용하였다. 기상열화에 의한 재색 및 중량변화, 물리적 표면열화, 목재조직의 변화를 종합적으로 고려할 때, AAC 처리시편을 제외한 ACQ, CCA, CuAz 처리시편은 기상열화에 대한 저항성이 있음을 알 수 있었다. 이러한 몇몇 방부처리재가 기상열화에 대하여 저항성을 나타내는 요인탐색을 위해 기상열화 산물을 분석하였는데, 그 결과, ACQ, CCA, CuAz 처리시편에서는 낮은 리그닌 함량이 측정되어 기상열화 저항성을 가지는 처리시편은 리그닌 열화가 적게 일어남을 나타냈다. 이는 방부제 유효성분이 목재 주성분 중 기상열화에 민감한 리그닌 구조에 정착함으로써 리그닌 열화에 대한 저항성이 발현되었기 때문으로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제30권2호
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• pp.108-114
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• 2002

변장 14.0 cm와 16.5 cm인 소나무 정각재의 가열판진공건조와 고주파진공건조간의 건조속도, 함수율분포와 비(比)에너지를 비교하였다. 고주파진공건조는 가열판진공건조보다 건조속도 및 변장이 건조속도에 미치는 영향이 컸었다. 가열판진공건조 목재의 재장방향, 두께방향과 폭방향의 함수율분포는 볼록 형태를 나타내었고, 고주파진공건조 목재는 오목 형태를 나타내었다. 가열판진공건조 목재의 폭방향과 두께방향간의 수분경사는 유사하였으나 고주파진공건조 목재의 경우는 폭방향의 수분경사가 두께방향보다 완만하였다. 가열판진공건조와 고주파 진공건조의 비(比)에너지곡선은 함수율이 감소할수록 증가하는 경향을 나타내었고, 가열판진공건조의 비(比)는 고주파진공건조보다 컸었다.