• Journal of Periodontal and Implant Science
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• 제32권2호
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• pp.303-314
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• 2002

This study was performed to evaluate the usability of Er:YAG laser for periodontal therapy. Forty dental root slabs ($5{\times}5{\times}2mm^3$) were prepared from human periodontally diseased extracted teeth and grouped into 4 groups: 1) control (root planing only), 2) root planing and irradiated with laser at 30mJ, 3) root planing and irradiated with laser at 60mJ, and 4) root planing and irradiated with laser at 100mJ. The root slabs were embedded in resin block before laser treatment. Er:YAG laser was irradiated under water irrigation with the tip held perpendicular to the root surface in contact mode. After Er:YAG laser irradiation or planing on the root surface, morphological changes have been observed under SEM, and the micro-hardness and Ca/P ratio were compared. 1. In the Control group, the root surface showed the directional change caused by root planing instrumentation, and the presence of smear layer, and no exposure of dentinal tubule was observed. Laser irradiated group showed surface changes with rough dentin surface of niche and depression and dentinal tubule exposure by the elimination of smear layer. 2. The micro-hardness of root surface in the laser irradiated group was higher than the control group. The higher energy output was applied, the higher micro-hardness on root surface was resulted. 3. The higher energy output was applied, the higher Ca/P ratio was observed. The higher Ca/P ratio in 60mJ group and 100mJ group was statistically significantly compared to the control group and the 30mJ group. These results suggest that Er:YAG laser irradiation on the periodontally diseased root surface could remove smear layer and increase the micro-hardness on root surface and Ca/P ratio which contribute to enhance the acid resistance of periodontally treated root surface.

• 한국산림과학회지
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• 제56권1호
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• pp.66-76
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• 1982

사방시공지(砂防施工地)에 널리 조림(造林)되는 리기다소나무의 근계분포(根系分布)와 토양(土壤)의 견밀도(堅密度)의 관계(関係)를 구명(究明)하고자 표본지(標本地)를 선정(選定) 대표목(代表木)의 경사하측(傾斜下側)에 환상(環状)의 토양단면(土壤斷面)을 만들어 각토층별(各土層別)로 토양경도(土壤硬度)를 산중식(山中式) Soil hardness tester로 측정(測定)하고 수근(樹根) (중세근(中細根))의 분포(分布)를 조사(調査)하여 분포(分布)한바 다음과 같이 요약(要約)할 수 있었다. 1) 토양(土壤)의 견밀도(堅密度)는 토심(土深)이 깊어짐에 따라 점차(漸次) 증가(增加)하여 평균(平均) 지표경도(指標硬度)는 I층(層)에서 14.6mm II층(層)에서 16.2mm, III층(層) 17.2mm, IV층(層)에서는 18.3mm, V층(層)에서는 19.8mm였다. 2) 수근(樹根) (중세근(中細根))은 표층(表層)에 이를수록 많이 분포(分布)하여 토층(土層)이 깊어짐에 따라 그 수(數)가 감소(減少)하여 I층(層) 수근(樹根)의 수(數)를 1(31%)로 할때 II층(層)은 0.84(26%), III층(層)은 0.6(18%), IV층(層)은 0.4(12%), V층(層)도 0.4(13%)이다. 3) 토양(土壤)의 견밀도(堅密度)와 수근(樹根)의 분포(分布)는 음(陰)의 상관관계(相関関係)에 있어 견밀도(堅密度)가 높아지면 이에따라 수근(樹根) 수(數)는 감소(減少)한다. 각(各) 토층별(土層別) 토양(土壤)의 견밀도(堅密度)와 수근분포(樹根分布)의 상관계수(相関係数)는 I층(層)은 -0.3875, II층(層)은 -0.5299, III층(層)은 -0.5573, IV층(層)은 -0.6922, V층(層)은 -0.7325, 전체평균(全体平均)은 -0.9469로서 모두 유의적(有意的)이었다. 4) 리기다소나무의 수근(樹根) (중세근(中細根))의 성장(成長)에 최적합(最適合)한 토양(土壤)의 견밀도(堅密度)는 지표경도(指標硬度)는 12.0~14.9mm로서 이 계급(階級)에 속(屬)하는 지표경도(指標硬度)는 33%이고 수근(樹根)의 분포(分布)는 41.8%이다. 또 지표경도(指標硬度) 20.9mm까지는 82%이나 수근(樹根) 93.2%가 분포(分布)하고 있어 지표경도(指標硬度) 20.9mm이하(以下)까지가 리기다소나무의 수근(樹根)의 생장(生長)에 적합(適合)하다고 사료(思料)된다.

• Journal of Ginseng Research
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• 제19권3호
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• pp.287-290
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• 1995

This study was conducted to elucidate the effect of physical properties of soil in nursery bed with different densities on growth of ginseng seedling. Stem length, leaf length and leaf width of ginseng seedling showed the decreasing tendency with increasing the hardness of the nursery soil. Fresh root weight per seedling and number of available seedlings were increased significantly with decrease of the soil hardness. For solid, liquid phases, bulk density and hardness of soil, negative correlations were shown in stem length, leaf length, leaf width, root weight per seeding, and number t of available seedlings. On the other hand, gas phase, air permeability and porosity of soil had positive correlations with stem length, leaf length, leaf width, root weight per seedling and number of available seedlings. Key words Yang-Jik nursery, ginseng seedling, soil physical properties.

• Journal of Periodontal and Implant Science
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• 제32권2호
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• pp.315-324
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• 2002

The purpose of this in vitro study was to evaluate the efficiency of Er:YAG laser on calculus removal and the morphologic changes and hardness of the irradiated surface at different power settings. This experiment used human teeth which were extracted due to periodontal disease and had a band of calculus. Forty root slabs ($5{\times}5mm$) were made and divided into control group and irradiated groups. Experimental groups were as follows; Control group (root planing), Group1 (irradiated with laser at 30mJ), Group2 (irradiated with laser at 60mJ), Group3 (irradiated with laser at 100mJ). Twelve root slab embedded in resin block were used in each group. Er:YAG laser was applied under water irrigation with the tip held perpendicular to the root surface in contact mode. The treatment time was measured until the calculus was removed completely under naked eyes. The efficiency of calculus removal was evaluated by the time for removal. Morphological changes of laser irradiated site were observed under SEM and the surface hardness was measured using a VH tester. The results were as follows; 1. The efficiency of laser scaling was increased with increasing the energy level of irradiation(p<0.05). 2. The morphological changes such as carbonization, crater and scale-like defects in the irradiated root surface were frequently observed with increasing the energy level. 3. The surface hardness tended to increase at 60mJ and 100mJ irradiated groups than that of control group. From the results evaluting on the efficiency, morphological change and surface hardness, lower energy level was suggested for the clinical application of the Er:YAG laser in scaling.

• 한국환경복원기술학회지
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• 제14권3호
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• pp.47-55
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• 2011

Cicada is a very familiar insect to people but habitat characteristics of them are not well known. To investigate habitat characteristics of cicada nymph, plant species, plant cover, soil hardness, accumulated organic mass, organic content in soil, and root density were investigated at 11 sites in an apartment complex garden in Seoul. Selected sites had different densities of cicada nymph case above the ground. Density of cicada nymph case was positively correlated with accumulated organic mass, organic content in soil, and root density and negatively correlated with soil hardness. Even though shrub coverage was not linearly correlated with the density of cicada nymph case, 80% cover of shrub was necessary for the high density of them. Data in this study suggested that organic matter in addition to root density be the primary limitation factor of cicada nymph and high amount of litter-fall decrease soil hardness through the increase of soil organic matter. This study suggests that the density of cicada nymph can be managed through organic content in soil.

• 한국자원식물학회지
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• 제8권3호
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• pp.217-222
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• 1995

Experiments were conducted to study the effect of IBA, mineral stone and stem hardness on rooting characteristics in mature Aloe vera plant. The rooting ability in matured Aloe vera was of highly significance when the amount of IBA treatment was increased to 5.000mg/l. The treatment of IBA 5.000mg/l, together with mineral stone(v/w 1.5 times), gave more root number, the length and the dry weight of root were, also, higher in semihard wood cutting than soft wood cutting in matured Aloe vera.

• 한국식품저장유통학회지
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• 제16권1호
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• pp.53-59
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• 2009

The purpose of this research is to develop bellflower (Platycodon grandiflorum) root and lotus (Nelumbo nucifera) root Jeonggwa as a health food. The quality characteristics of Jeonggwa to which 0-8% (w/w) of Omija (Schizandra chinensis Baillon) water extract was added were investigated. The moisture contents of bellflower root Jeonggwa were 14.9-18.0%, where as that of lotus root Jeonggwa was 6.9-8.4%. The acidity of bellflower root Jeonggwa was 0.477-0.585% and that of lotus root Jeonggwa was 0.513-0.572%; values increasing levels of Omija extract. The lightness (L) and yellowness (b) values of bellflower root Jeonggwa decreased with increasing amounts of Omija extract, and the lightness (L), redness (a) and yellowness (b) values of lotus root Jeonggwa decreased with increasing Omija extract concentration (p<0.05). In mechanical tests with bellflower root Jeonggwa, the highest values of hardness and strength were seen at 2% (w/w) extract, of cohesiveness were seen with 4-8%, of springiness with 2-6%, of gumminess with 6-8%, and of brittleness with 4-6% (all p<0.01). In mechanical tests with lotus root Jeonggwa, the highest values of hardness and springiness were at 0 and 6% extract, respectively, whereas strength, gumminess and brittleness were at 6-8% Omija extract (all p<0.01). In sensory evaluation, the highest acceptability of bellflower root Jeonggwa was seen with 4% extract and that of lotus root Jeonggwa was seen with 2% extract.

• 한국조리학회지
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• 제16권1호
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• pp.180-190
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• 2010

본 연구는 연근가루 첨가량을 달리하여 청포묵을 제조한 후 $4^{\circ}C$에서 5일간 저장하면서 품질 특성을 조사하였다. 연근가루를 첨가한 청포묵의 수분 함량은 86.78~88.88%이었다. L값은 연근가루 첨가량이 증가할수록 감소하였으나 a값과 b값은 유의하게 증가하였다(p<0.05). 관능검사 결과, 색과 맛은 연근가루 첨가량이 증가할수록 감소하였다. 향미와 광택은 시료간에 유의적인 차이는 없었다. 그리고 투명도와 탄력성은 무첨가군과 연근가루 5% 첨가할 때 가장 높았다. 단단한 정도는 연근가루 첨가량이 증가할수록 유의하게 감소하였다(p<0.05). 전반적인 수용도는 무첨가군과 연근가루 5% 첨가할 때 가장 높은 평가를 받았다. 조직감은 경도, 검성, 씹힘성은 저장 1일째에 유의하게 급격히 감소하였다(p<0.05). 응집성은 연근가루 첨가량에 따라 시료간에 유의적인 차이는 없었다. 부착성은 무첨가군과 연근가루 5, 10, 15%간에는 유의적인 차이는 없었다. 이수율은 저장 기간 동안 증가하였다. 이상의 결과로 연근가루를 첨가한 청포묵을 제조할 때 녹두전분 19 g, 연근가루 1 g, 소금 0.1 g, 물 160 mL를 첨가하는 것이 가장 바람직하겠다.

• 동아시아식생활학회지
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• 제20권4호
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• pp.516-523
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• 2010

This study was conducted to investigate the physicochemical and sensory characteristics of tofu prepared with the addition of lotus root powder (LRP). The moisture, crude ash, carbohydrate, crude protein, and crude lipid contents of the lotus root powder were 8.29%, 4.73%, 30.66%, 47.84%, and 8.48%, respectively. The yield rate of the tofu did not differ significantly according to the level of added LRP; however, there was a significant decrease in pH and a significant increase in acidity. The L and b values of the tofu decreased as the amount of LRP in the formulation increased, whereas the a value increased. Furthermore, hardness and cohesiveness increased significantly as the level of LRP increased. In sensory evaluation, LRP tofu had low scores in air cell size and a beany smell, but high scores in hardness. In terms of overall acceptability, the preferred tofu samples were the control and that containing 0.3% lotus root powder.

• 한국식품조리과학회지
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• 제25권2호
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• pp.143-149
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• 2009

본 연구는 기능성을 가지고 있는 연근을 우리나라 전통 한과류인 진말다식에 0%, 20%, 40%, 60%, 80%로 첨가하여 품질특성을 평가 한 후 연근 다식의 표준레시피를 제시하고자 하였다. 실험 결과를 요약하면 다음과 같다. 연근 다식의 수분함량은 연근가루 첨가량이 증가할수록 수분함량이 유의적으로 증가하였다. 연근 다식의 색도 변화에서는 연근가루의 첨가량이 증가할수록 L 값, a 값, b 값이 유의적으로 감소하는 경향이었다. 연근 다식의 물성에서는 연근가루의 첨가비율이 증가할수록 경도(hardness), 검성(gumminess), 씹힘성(chewiness), 탄력성(springiness)과 응집성(cohesiveness)은 감소하는 경향이었다. 부착성(adhesiveness)은 연근가루 첨가량이 증가할수록 증가하는 경향이었다. 연근 다식의 정량적 묘사분석에서 연근가루 첨가량이 증가할수록 색(color), 향(flavor), 맛(taste), 씹힘성(chewiness)의 강도가 높았으며, 부드러움(softness)은 시료 간에 유의적인 차이가 없었다. 기호도 검사에서는 연근가루 40% 첨가군(LR40)이 색, 향, 맛, 전체적 기호도에서 가장 높게 평가되었다. 이상의 연구를 통해 연근 다식으로 가장 적당한 제조 방법은 볶은 밀가루 60 g, 연근가루 40 g, 꿀 80 g으로 제조한 연근 다식이었다.