• Title/Summary/Keyword: Elapsed Year

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Characteristics of Soil Erosion on the Forest Fired Sites by Using Rainfall Simulator (인공강우장치를 이용한 산불발생지의 토양침식 특성에 관한 연구)

  • Lee, Heon Ho;Joo, Jae Duk
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.649-656
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    • 2006
  • The purpose of study is to measure soil erosion quantity for elapsed four years from the fire on forest fired sites of Dong-gu, Daegu. This study was conducted to investigate the characteristics of soil erosion by fire occurrence influencing on the soil erosion were. Also analysis result follows that the relations between soil erosion quantity and rainfall intensity, the slope and elapsed year. The results analysed were as follows: 1. Soil erosion by year of occurrence of forest fire was increased 1.9 to 5.7 times as rainfall intensity was increased by 30 m/hr, and 1.4 to 14.2% as degree of slope was increased by $10^{\circ}$. 2. In the first year of forest fire occurrence, soil erosion was fairly heavy for 10 minutes of initial rainfall of which rainfall intensity was 80 m/hr and degree of slope was $30^{\circ}$. The amount of soil erosion was gradually reduced as elapsed time. From two years after fire, the amount of soil erosion by rainfall intensity and degree of slope was nearly constant. 3. The amount of soil erosion by rainfall intensity and slope in accordance with elapsed time after fire was reduced 28.9 to 94.1% in three years after occurrence of forest fire as compared to the first year of fire. Soil erosion was fairly heavy by rainfall intensity and slope in the first year of fire, but it was gradually reduced from two years after fire. 4. In the analysis on influences of each factors on the amount of soil erosion on forest fired sites, the amount of soil erosion was significant differences in major impacts of each rainfall intensity, degree of slope and elapsed year after fire and interaction of rainfall intensity${\times}$degree of slope and rainfall intensity${\times}$elapsed year after fire, but no differences were observed in interaction of degree of slope${\times}$elapsed year after fire and rainfall intensity${\times}$degree of slope${\times}$elapsed year after fire. Rainfall intensity was the most affecting factor on the amount of soil erosion and followed by degree of slope and elapsed year after fire. 5. For correlation between soil erosion and affecting three factors, soil erosion showed significant positive relation with rainfall intensity and degree of slope at I % level, and significant negative relation with elapsed year after fire at 1 % level. 6. As a result of regression of affecting three factors on soil erosion. rainfall intensity was most significant impact factor in explaining the amount of soil erosion on forest fired sites, followed by degree of slope and elapsed year after forest fire. 7. The formula for estimating soil erosion using rainfall intensity, degree of slope and elapsed year after forest fire occurrence was made. S.E = 0.092R.I + 0.211D.S - 0.942E.Y(S.E : Soil erosion, R.I : Rainfall intensity, D.S : Degree of slope, E.Y : Elapsed year after forest fire occurrence)

Regression Analysis of Vibration Phenomenon on the Load Capacity and Elapsed Year of a Power Transformer

  • Kim, Young-Dal
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.3
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    • pp.30-37
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    • 2009
  • The majority of the causes for the failures of power transformers in operation are mechanical defects due to vibration. The vibration phenomenon was measured from the power transformers in operation in the substations. The vibration measurement was performed in a $6{\times}4$ structure on one side of each transformer. The vibrations of the measured points were presented in two and three dimensions and analyzed. The results, according to the elapsed year of the transformer and the load capacity to the transformer, were analyzed. These results could be used as basic data with which to establish vibration standards for power transformers. In addition, the load capacity-vibration phenomenon correlation was examined and regression analysis was performed to derive the estimation function. The vibration phenomenon according to the elapsed yeah was also estimated to derive the function. Then the analysis of the power transformers was used to set vibration standards for them based on the vibration data.

Dominant Species and Factors Related with Plant Coverage in the Cutting Slopes of Forest Road -In Jeollabuk-do Region­- (임도 절토비탈면의 우점식물과 식물피복에 미치는 인자들의 영향 -­전라북도를 대상으로­-)

  • Park, Moon-Su
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.1
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    • pp.19-27
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    • 2002
  • To investigate the dominant species and factors related with plant coverage by road structures and forest environment factors, forest roads elapsed from one year to twelve year after construction had been selected in six county(Gochang-gun, Muju-gun, Imsil-gun, Jangsu-gun, Jeongup-shi and Jinan-gun), and 20m segments were continuously set up in each road. The results obtained from this study are summarized as follows: The species diversity of Gochang, Muju, Imsil, Jangsu, Jeongup and Jinan were 1.304, 1.267, 1.308, 1.193, 1.289 and 1.018, respectively. In process of years, plant coverage was increased gradually and average of plant coverage was 15.3% in forest roads which elapsed three year, and was 86.5% in forest roads which elapsed nine year after construction. The dominant species in the cutting slope of surveyed area were covered with Arundinella hirta, Pinus rigida, Miscanthus sinensis var. purpurascens, Artemisia princeps var. orientalis, Pinus densiflora, Oplismenus undulatifolius, Rubus coreanus, Lysimachia clethroides, Lespedeza bicolor, and Alnus hirsuta of the 152 species. The high correlated factors between plant coverage and variables in cutting slopes appeared elapsed year, soil hardness, mean annual precipitation, vertical grade, inslope and arid humidity in surveyed area.

Clinical Analysis of Symptoms and Oriental Medical Prescriptions According to Elapsed Time of Stroke in Oriental Medical Hospital Inpatients

  • Yun, Hen-Ja;Sung, Kang-Keyng
    • Herbal Formula Science
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    • v.20 no.1
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    • pp.133-147
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    • 2012
  • Objectives : This study was intended to understand characteristics of symptoms, oriental medicine prescription and laboratory test results according to elapsed time of stroke. Methods : Through the medical records of 205 stroke inpatients in the oriental medical hospital in the year 2010, we investigated manifested symptoms, administered oriental medicine prescription and clinical pathological examination results. Collected items were classified to depend on stroke types, cerebral infarction and hemorrhage. We analyzed association between manifested symptoms, the oriental medicine prescription, and laboratory test results of stroke patients and elapsed time. Chi-square tests were performed to determine the significance level of association. Results : All symptoms, prescriptions and laboratory test results in cerebral infarction patients were associated with elapsed time. Especially, symptoms, prescriptions and pathological examination results showed very high statistical significance with elapsed time (a symptom; chi-square(df)=164.3(22), p<0.001, prescription; chi-square(df)=93.5(22), p<0.001, and pathological examination results; chi-square(df)=164.3(22), p<0.0004). But in the case of cerebral hemorrhage, there was not statistical significance. Conclusions : The elapsed time of stroke may be an essential requisite in catching symptoms and prescribing for stroke patients in oriental medical treatment.

Characteristics of Surface Flow on the Forest Fire Sites by Using Rainfall Simulator (인공강우장치를 이용한 산불발생지의 지표유출 특성에 관한 연구)

  • Lee, Heon Ho;Joo, Jae duk
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.350-357
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    • 2006
  • For the purpose of this study, the characteristics of surface flow through the survey of rainfall intensity and degree of slope on fire sites by using rainfall simulator was examined and analysed. And also the relationship between the amount of surface flow and rainfall intensity, degree of slope and elapsed year after forest fire occurrence influencing on the surface flow were analysed. The results obtained were as follows: 1. The amount of surface flow by year of occurrence of forest fire was increased 2,2 to 3,2 times as rainfall intensity was increased by 30 mm/hr, and 1.5 to 1.9 times as degree of slope was increased by $10^{\circ}$, 2, Even though ground vegetation in forest fire sites was recovered more than 80%, the amount of surface flow in initial rainfall was relatively much and it seemed that vegetation didn't play substantial roles in reducing runoff. 3, The amount of surface flow by rainfall intensity and degree of slope in accordance with elapsed years after forest fire was reduced 22,3% to 41,8% in three years after fire as compared to the first year of fire occurrence. The amount of surface flow were significantly differentiated by rainfall intensity and degree of slope in the first year of fire occurrence and the difference were gradually reduced afterwards. 4. In the analysis on influences of each factors on the amount of surface flow on forest fire sites, the amount of surface flow was significant differences in major impacts of each rainfall intensity, degree of slope and elapsed year after fire and interaction of rainfall intensity ${\times}$ degree of slope and rainfall intensity ${\times}$ elapsed year after fire, but no differences were observed in interaction of degree of slope ${\times}$ elapsed year after tire and rainfall intensity ${\times}$ degree of slope ${\times}$ elapsed year after tire. Rainfall intensity was the most affecting factor on the amount of surface flow and followed by degree of slope and elapsed year after fire.

Changing of Vegetation Coverage through Elapsed Years on Cutting Slope in Forest Roads (시간경과에 따른 임도 절토비탈면의 식생피복도 변화)

  • Jeon, Kwon-Seok;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.3
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    • pp.14-25
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    • 2004
  • The purpose of this study was investigated to the change of vegetation coverage by elapsed years on the cut slope of forest road in Jinju-si. The results obtained could be summarized as follows; The plant coverage on the cut slope of forest road was decreased hastily in first and second year after seeding. The plant coverage on the cut slope of forest road was increased as growth of seed-sprayed from third year. But the plants were began to competition with between sprayed seeds and invaded plants from third to fifth year after seed-spray. The numbers of invading plants were gradually increased as 581 individuals from sixth year after seed-spray. The cut slopes of the forest roads turned to a good site condition for growing of invasion plants. And also the total coverage on cut slope of forest roads by invading of surrounding plants was increased more. It showed that plant invasion on cut-slopes of forest roads would be mostly influenced by surrounding plants. The number of surrounding plants on the cut-slopes of forest roads was 59 species, and the number of invading plants showed 65 species. The invading species were high in order of Boehmeria tricuspis, Oplismens undulatifolius, Miscanthus sinensis var. purpurascens, Erechtites hieracifolia and Artemisia princeps var. Orientalis In the stepwise regression analysis, main factors affecting the coverage of vegetation on the cut-slopes of forest road showed in order of elapsed years, gravel contents(30~50%), middle, sandy loam, sandy clay-loam, soil hardness, aspect(NS), concave(凹) type and gravel contents(15~30%).

A STUDIES OF CHANGES OF THE TEETH AS THE TIME ELAPSED SINCE DEATH (사후 경과시간에 따른 치아경조직의 변화에 관한 연구)

  • Ock, Sun Nam;Kim, Chong Youl
    • Journal of Oral Medicine and Pain
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    • v.12 no.1
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    • pp.27-40
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    • 1987
  • When the men die, uniform changes progress. Many investigators have studied about the time after death, but it's very difficult to measure the time elapsed since death, particularly in highly decomposed or probably skeletonized bodies. But the teeth are very stable to the changes of physical and chemical properties and their changes are very slow. At this point of view, the author studied this theme as one of the pioneers in our country. In this study, the author observed the degree of the dentinal expansion and the crack of enamel and cementum of the teeth which had been extracted from December, 1983 to September, 1987. The teeth were extracted from the male and female who was 18 to 85 year old. The results are followed; 1. The degree of dentinal expansion increased rapidly until 7 months with high degree and then decreased slowly. 2. The equation of regression for representing x as the degree of the dentinal expansion and y as the time elapsed since death, is y = 29.43-1.13x (p<0.05) 3. The crack of the enamel surface seemed to begin at 1 year from extraction and to increase apparently before or after 20 months. 4. The crack of the cementum began at 3 months from extraction and dendrite crack began at 16 months from extraction. After this, the crack increase continuously and the rate of cracking were more rapid as compared with that of enamel. 5. It seems to be useful to measure the time elapsed since death using the degree of dentinal expansion and the crack of enamel and cementum, particularly in the old bodies after death.

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Influencing Factors on Health Behavior Compliance in Men Who Underwent Percutaneous Coronary Intervention: Focusing on the Elapsed Period (관상동맥중재술을 받은 남성의 건강행위 이행에 미치는 영향요인: 경과기간을 중심으로)

  • Ha, Haeng-Ju;Seo, Minjeong
    • Journal of Digital Convergence
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    • v.19 no.12
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    • pp.661-673
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    • 2021
  • This study is a descriptive study to understand the effect on the health behavior compliance of men who got coronary intervention, focusing on the elapsed period. The subjects of this study were 249 men who underwent coronary intervention at a university hospital, and the collected data were analyzed using Stepwise multiple regression. As a result of the study, the influencing factors the implementation of healthy behaviors were self-regulation(β=0.35, p<.001), risk factors among educational request(β=-0.26, p<.001), and the elapsed period(β=0.19, p<.001), marital status(β=0.15, p=.001), educational level(β=-0.12, p=.035), and the total explanatory power was 29.1%. IIn order to increase the health behavior performance of male patients who underwent coronary intervention, it is necessary to develop a program that can strengthen the autonomous motivation of subjects with high severity and elapsed time of less than 1 year and more than 1 year.

Studies on the Ecological Change of the Plant Community in the Erosion-Controlled and Rehabilitated Areas - During 9~26 Years After Erosion Control Works - (사방시공지 식물사회의 생태학적 변화에 관한 연구(V) - 사방시공 후 9~26년 간의 변화 -)

  • Lee, Hyun-Kyu
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.5
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    • pp.59-69
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    • 2003
  • Most denuded mountain areas in Korea were completely stabilized by the successful work of the 1st and 2nd 10-year Forest Development Plans which targeted the reforestation of denuded forest lands. The objectives of this study are (1) to estimate the depth of organic horizon in the soil profile, (2) to investigate the change of vegetation structure, (3) to estimate the change of biomass in the erosion controlled and rehabilitated mountain areas with the passage of time. This study was carried out as the 5th times. The first study began in the year of 1985, the second study was in the year of 1988, the third study was in the year of 1992, 4th was in the year of 1998 and 5th was in the year of 2002. The first study started in the study sites which elapsed 9 years after erosion control works. The results of the study were as follows : The increase rate of soil thickness was estimated to $Y_{(cm)}=2.906log_{(yr)}-3.2476(r^2=0.917)$ during 26 years after erosion control works. The important value of pines decreased to 14.7% on upper layer. But, the important value of alders. which did not plant on erosion control work increased to 27.1%. The decrease of whole crown projection indicates that pines. and alders were heavily injured by pine leaf gall midge in the year of 1993, 1995 years and Agelastica coerulea Baly in the year of 1986, 1987 years at Yoju-gun. The young growth of pines and alders not appeared on the soil surface which elapsed 26 years after erosion control works. On the lower layer, oaks occupied over 50% in I.V, RD, RC, RF. In process of years, the increase of biomass estimated to be $Y_{(t/ha)}={0.7505X_{(yr)}}^{1.6335}\;(r^2=0.9712)$ for 26 years after erosion control works.

Statistical analysis of hazen-williams C and influencing factors in multi-regional water supply system (광역상수도 유속계수와 영향인자에 관한 통계적 분석)

  • Kim, Bumjun;Kim, Gilho;Kim, Hung soo
    • Journal of Korea Water Resources Association
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    • v.49 no.5
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    • pp.399-410
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    • 2016
  • In case of the application of Hazen-Williams C for design, operation or maintenance of water supply system, field situations always should be reflected on the factors. In this study, the relationships between C factors and influencing factors are analyzed using statistical techniques with 174 measured C factor data collected in periodic inspection for safety diagnosis in multi-regional water supply systems. To analyze their relationships, cross analysis, one-way ANOVA, correlation analysis were conducted. Analysis results showed that C factors had high correlations with both of elapsed year and pipe diameter and were relatively highly affected by coating material among influencing factors with the categorical type. On the other hand, elapsed year, pipe diameter and water type were meaningful influencing factors according to the results of multiple regression analysis. The Cluster analysis revealed that C factors had a tendency of being fundamentally classified on the basis of the elapsed year of about 20 years and the pipe diameter of 1500mm. Although C factors were generally greatly affected by elapsed year, size of pipe diameter relatively had an large influence on values of them in case of large diameter pipes. Lastly, It can be suggested that C factor estimation formulas using multiple regression analysis and clustering analysis in this study, can be applied as decision standards of C factor in multi-regional water supply systems.