• 한국산림과학회지
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• 제107권4호
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• pp.412-421
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• 2018

본 연구는 산림시업이 소나무임분의 수관연료특성 변화에 미치는 영향을 예측하고자 하였다. 본 연구에서는 국가산림자원자료 중 시업지 1,085 stands, 비시업지 349 stands의 표본점 자료를 분석에 이용하였으며, Weibull 함수를 사용하여 시간에 따른 임분생장과 수관연료특성에 대해 예측하였다. 산림시업유무에 따른 수관연료특성을 비교해본 결과 비시업지 임분이 시업지 임분에 비해 평균 수관연료량은 약 14% 높게 나타났으며, 연소가능한 수관연료밀도 또한 약 16% 높게 나타났다. Weibull 함수를 사용하여 임령 40년, 50년, 60년의 생장 예측과 수관연료특성 변화를 비교해본 결과, 시업지 임분은 시간이 지남에 따라 중경목, 대경목에 최대임목본수의 증가가 예측된 반면, 비시업지 임분은 소경목, 중경목에서 최대임목본수가 예측되었다. 비시업지 임분이 시업지 임분에 비해 수관연료량, 수관연료밀도의 증가량이 높게 나타나 수관화로의 확산 가능성이 높은 것으로 사료되었다.

• Journal of Forest and Environmental Science
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• 제39권2호
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• pp.73-80
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• 2023

Little is known of the life history of Garcinia kola; the objective of this study, therefore, was to assess the fruiting age and tree size of the species in a coastal humid tropical climate plantation condition. A total 103 trees were used in the study viz; 80 ten-year-old trees at reproductive maturity onset and 13 thirty-year-old trees with several cycles of reproduction that constitute two independent variables. Data collected were age of onset of flowering and size at reproductive maturity onset. Relative size at reproductive maturity onset (RSOM) was estimated as size at reproductive maturity onset (SOM) divided by asymptotic maximal size (AMS). Data analysis was conducted using pairwise t-test and principal component analysis (PCA). Reproductive maturity onset (flowering) was recorded in the ten-year-old stand eight (8) years after planting. Mean size at reproductive maturity onset (SOM) was height 5.32±1.7 m, dbh 0.11±0.03 m, total number of branches was 29.6±7.3, crown depth 5.24±1.05 m, crown diameter was 4.78±0.7 m, branch diameter 0.098±0.01 m, leaf length 0.13±0.02 m, leaf breadth 0.37±0.01 m, twig length 0.35±0.11 m and leaf per twig 6±0.84 and asymptotic maximal size (AMS) was height 19.85±0.76 m, dbh 0.95±0.09 m, total number of branches 62±5, crown depth 18.83±0.7 m, crown diameter 12.5±1.64 m, branch diameter 0.5±1.6 m, leaf length 0.16±0.023 m, leaf breadth 0.45±0.12 m, twig length 0.37±0.11 m and leaf per twig 19±7.5. Pairwise t-test analysis showed there was significant differences between SOM and AMS in all growth factors except leaf length, leaf breadth, and twig length. Highest relative size at reproductive maturity onset (RSOM) was recorded in leaf length 0.82, twig length 0.82, and leaf breadth 0.80, while, the lowest was branch diameter 0.11. Four components out of the total of eleven were extracted to explain the relationship in RSOM: Principal component one (PC1) explained 37.23%; PC2 26.4%, PC3 22.73%, and PC4 13.64%.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2022년도 하계학술대회
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• pp.78-80
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• 2022

Strawberry (Fragaria × ananassa) cultivation methods are rapidly changing from traditional soil cultivation to high bed hydroponics, which are easy to agricultural working. The objective was to evaluate the growth characteristics of three strawberry cultivars cultivated high bed system. The "Seolhyang", "Altaking", and "Keumsil" strawberry plants were transplanted in a glass-type greenhouse at Kyungpook National University Gunwi Agricultural Field. The cultivation period was approximately seven months from September 17, 2021 to April 21, 2022. Growth parameters measured including the number of leaves, plant height, petiole length, leaf length, leaf width, and crown diameter at two-week intervals. The environmental parameters for each location in the greenhouse were collected. Plant height in all cultivars continued to decrease from the early stage to the late stage of growth. The crown diameter was increased by 50 DAT, and then gradually decreased until late growth stage in all cultivars. Results indicated that the growth parameters represented to vary according to the cultivar of strawberry plants.

• 대한치과재료학회지
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• 제45권4호
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• pp.287-300
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• 2018

본 연구의 목적은 3차원 스캐너를 이용하여 현재 시판중인 두 종류의 대구치용 기성금속관의 형태적 특성을 비교하는 것이며, 또한 crimping 후의 치경부측 형태 변화를 분석 후 비교하는 것이다. 3차원 스캐너를 이용하여 상, 하악 대구치용 기성금속관인 PO-96과 PERMACROWN의 크기, crown index, 치경부 수렴도를 계측하였다. 이후 기성금속관들은 crimping을 통하여 치경부 형태를 조정하였고 3차원 스캐너를 통해 다시 스캔을 시행한 후 형태적 변화를 분석하였다. 상악 기성금속관의 폭경은 PERMACROWN이 PO-96에 비해 협설로 더 컸고 근원심으로는 더 작았으며, 치경부의 근원심 형태는 더 볼록하였다. 하악에서는 PERMACROWN이 PO-96에 비해 폭경은 협설로 작고 근원심으로 컸으며, 치경부의 근원심, 협설측 모두 더 볼록한 형태를 보였다. 그리고 두 기성금속관 모두 crimping 이후 치경부 변연 둘레는 감소하였다. 두 기성금속관은 크기, 형태, 치경부 수렴도에서 형태학적 차이를 보였다. 두 대구치용 기성금속관 모두 치경부 형태가 부여되어있지만 더 나은 변연적합을 위해서는 추가적인 crimping이 필요하다.

• 농업생명과학연구
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• 제45권2호
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• pp.51-59
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• 2011

붉은고로쇠나무의 적정 식재밀도와 대체조림수로서의 적정 조림시기를 위한 기초 자료를 제공하기 위해 천연림과 조림지에서 생장인자분석과 흉고직경 10 cm 도달연수를 측정하였다. 천연림에서 흉고직경은 수관폭과 높은 상관관계(E-W: r=0.82, S-N: r=0.76)를 나타내었고 조림지의 흉고직경과 수관폭도 높은 상관관계 (E-W: r=0.76, S-N: r=0.90)를 나타내었다. 천연림에서 흉고직경 10cm에 도달하는 평균연수는 $21.1{\pm}7.0$년, 조림지에서는 $9.2{\pm}1.3$년으로 측정되어 최초 수액채취가 가능한 시기는 인공조림시 천연갱신을 통해 형성된 자생지 보다 약 2.3배 단축되는 것으로 나타났다.

• Journal of Forest and Environmental Science
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• 제37권3호
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• pp.193-205
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• 2021

The importance of forests and trees in climate change mitigation and soil nutrient cycling cannot be overemphasized. This study assessed the above-ground carbon stock of two exotic and two indigenous tree species - Gmelina arborea, Tectona grandis, Khaya grandifoliola and Nauclea diderrichii and their litter impact on soil nutrient content of an arboretum within the University of Port Harcourt, Nigeria. Data were collected from equal sample plots from the four species' compartments. Tree growth variables including total height, diameter at breast height, crown height, crown diameter and merchantable height were measured for the estimation of above-ground carbon stock. Soil samples were collected from a depth of 0-30 cm from each compartment and analyzed for particle size distribution, organic carbon, total nitrogen, available phosphorus, exchangeable bases, exchangeable acidity, cation exchange capacity, base saturation, pH, Manganese, Iron, Copper and Zinc. Analysis of Variance (ANOVA) was used to test for significant difference (p<0.05) in the carbon contents of the four species and the soil nutrient contents of the different species' compartments. Pearson correlation was used to assess the relationships between the carbon contents, growth parameters and soil parameters. The highest and lowest carbon stock per hectare was observed for G. arborea (151.52 t.ha^-1) and K. grandifoliola (45.45 t.ha^-1) respectively. Cation exchange capacity and base saturation were highest and lowest for soil under G. arborea and K. grandifoliola respectively. The pH was highest and lowest for soil under G. arborea and T. grandis respectively. Carbon stock correlated positively with dbh, crown diameter, merchantable height and Zn and negatively with base saturation. The study revealed that G. arborea and N. diderrichii can effectively be used for reforestation and afforestation programmes aimed at climate change mitigation across Nigeria. Therefore, policies to encourage and enhance their planting should be encouraged.

• 대한치과기공학회지
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• 제30권2호
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• pp.87-92
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• 2008

Purpose: In this study, we tried to compare marginal accuracy when produce ceramic crown using all ceramic materials and existent metal-ceramic system. Material and methods: All-ceramic systems were E-max (Ivoclar/Vivadent, Lichtenstein), Lava(3M, U.S.A.) and Wol-ceram(Teamziereis, Germany). Metal-ceramic system(PFG) was composed of Au-Pt alloy (Metalor, Switzerlandand) and overlying ceramic(D-sign, Ivoclar/Vivadent, Lichtenstein). We fabricated metal master die with upper diameter of 7.95mm, bottom diameter of 9.00mm, height of 5.00mm, and taper of $6^{\circ}$. All ceramic system used 0.5mm thickness ceramic coping, while metalceramic system used 0.3 thickness metal coping. By adding dentin and enamel ceramics on each coping, a crown with a proximal thickness of 1.0 mm and occlusal thickness of 2.0mm was fabricated. Pressure of 2kg was applied for 10 seconds on each crown with static load compressor. Before and after cementation, we measured the marginal gap at 4 points of each crown using optical microscope. The data was analyzed using a Student's t test and repeated-measures of analyses of variance(ANOVA) followed by a Bonferroni test. A p value<0.05 was considered significant. Results: As experiment results, marginal accuracy of wol-ceram and Lava is no good when compared with marginal accuracy of PFG. But marginal accuracy of E.max is good when compared with PFG. This result showed not significant. The marginal accuracy of E.max is good when compared with marginal accuracy of wol-ceram and Lava. Conclusion: The marginal accuracy of E.max is very good when compared with marginal accuracy of another group.

• 원예과학기술지
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• 제32권1호
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• pp.41-45
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• 2014

본 실험은 고랭지에서 신품종 사계성 딸기 '고하' 품종의 생육 및 수량에 영향을 미치는 관부수를 구명하고자 실시하였다. 정식은 4월 29일에 재식거리를 $55{\times}30cm$로 실시하였으며, 시험구 처리는 관부수를 1, 3, 5개로 하고 대조구로 방임을 두었다. 생육초기에 관부수가 적을수록 잎은 커졌고, 화방경은 굵어졌다. 최종수확 시 초장은 크라운수가 많을수록 길어졌다. 생체중은 관부수 방임구가 118g으로 관부수 1개구의 40.8g보다 77.2g이 더 무거웠다. 발생된 화방수는 관부수 5개구와 방임구가 20.1개로 관부수 1개구의 6.8개에 비해 13.3개가 더 많았다. 그러나 관부수에 따른 과실품질의 유의적인 차이는 보이지 않았다. 관부수가 많을수록 평균과중은 가벼웠으며, 상품과율은 감소하였다. 상품수량은 관부수 방임구가 $17,372kg{\cdot}ha^{-1}$로 가장 많았으며, 관부수 1개구에 비해 68% 증수되었다. 따라서 고랭지 사계성 딸기 '고하'의 여름재배 시 안정생산을 위해서는 관부는 방임하며, 화방굵기가 3mm 이하인 화방은 제거하는 것이 가장 적당하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.41-44
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• 2008

In this paper, major species of tree were discriminated in compartment by using LiDAR data and optic imagery. This is an important work in forest field. A current digital stock map has created the aerial photo and collecting survey data. Unlike high resolution imagery, LiDAR data is not influenced by topographic effects since it is an active sensory system. LiDAR system can measure three dimension information of individual tree. And the main methods of this study were to extract reliable the individual tree and analysis techniques to facilitate the used LiDAR data for calculating tree crown 2D parameter. We should estimate the forest inventory for calculating parameter. 2D parameter has need of area, perimeter, diameter, height, crown shape, etc. Eventually, major species of tree were determined the tree parameters, compared a digital stock map.

• 대한치과기공학회지
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• 제42권3호
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• pp.220-227
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• 2020

Purpose: This study aims to investigate the cusp variation pattern of the Korean mandibular second premolar and to determine the difference in tooth diameter and surface area using a virtual three-dimensional model. Methods: Dental casts from 69 students were scanned as a virtual dental models with a three-dimensional dental model scanner. Tooth diameter, absolute and relative individual areas, total crown area, the number of lingual cusps and central groove pattern were analyzed using RapidForm 2004. The Mann-Whitney U-test and the Kruskal-Wallis test were performed to verify sexual dimorphism, the difference in tooth diameter and surface according to the cusp variation pattern (α=0.05). Results: There was no significant difference except in buccolingual diameter (p<0.05) and buccolingual diameter at the cervix (p<0.05). The relative surface area of the total clinical crown was 65.76% for the buccal half and 34.24% for the lingual half, with a ratio of 2:1. In the case of the presence of two lingual cusps, the ratio was 21.47% for the mesiolingual half and 14.12% for the distaolingual half, with a ratio of 3:2. The dominant central groove patterns of the second premolar were the H-pattern (42.0%), followed by the Y-pattern (37.7%), then the U-pattern (20.3%). The relative buccal half was largest in the U-pattern central groove and the relative lingual half was largest in the Y-pattern central groove (p<0.05). Conclusion: This study is significant in that it measured quantitative surface areas and the findings could be a meaningful reference to comprehend dental anatomy in Koreans.