• Title/Summary/Keyword: elapsed years

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Analysis of the Sedimentation Status Test for Type-3 Dry Chemical Powder with Changes in Internal Pressure of the Dry Chemical Extinguisher (분말소화기의 내부압력 변화에 따른 제3종 분말소화약제의 침강도 시험)

  • Ju-Dal Son;Seo-Young Kim;Ha-Sung Kong
    • Journal of the Korea Safety Management & Science
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    • v.25 no.1
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    • pp.67-74
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    • 2023
  • This study aims to measure sedimentation status change with the changes in internal pressure for dry chemical extinguishers of various use periods and analyze the suitability of the fire extinguishers' performance criteria. When the internal pressure of the fire extinguisher is 0%, 2 out of 10 new dry chemical powders for the 5 elapsed years were noted to be suitable, including 3 recycled dry chemical powders with 5 elapsed years that were found eligible. One out of 10 new dry chemical powders for 10 elapsed years was shown as suitable. Also, one new dry chemical powder for 13 elapsed years was suitable. When the internal pressure of the fire extinguisher was 50%, all 10 out of 10 new dry chemical powders for 5 years, recycled one with 5 elapsed years, and a new one with 10 elapsed years were found to be suitable, while 9 new dry chemical powders for 13 years were shown as suitable. When the internal pressure of the fire extinguisher was normal, new ones with 5 elapsed years, recycled ones with 5 elapsed years, new ones with 10 elapsed years, and new ones with 13 elapsed years were all 10 out of 10 samples noted as suitable. In summarizing the experiment results, it was found that the sedimentation status, one of the fire extinguisher's physical properties experiments, affects the fire extinguisher's performance criteria rather than the change with use periods.

Influence of Elapsed Years and Physical Properties on Vegetation Invasion of Forest Road Slope (임도시공경과년수 및 물리적 특성이 임도사면의 식생 침입에 미치는 영향)

  • Lee, Joon Woo;Choo, Gab-Chul;Choi, Yeon Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.1
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    • pp.28-34
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    • 2002
  • This study was carried out to analyze the effects of elapsed years and physical properties on invaded vegetation of forest road slope. For the study, 8 forest roads in Asan-si of Chungcheongnam-do were selected and 15 factors that might influence on vegetation invasion were analyzed. In generally, vegetation coverage of slope have increased with the elapsed years. But invasion species have decreased in the cut-slope and increased in fill-slope. There was no significant correlation between rate of vegetation coverage and elapsed years, but rate of vegetation coverage was strongly related with slope aspect. And the species of invasion vegetation affected mostly by the elapsed years and slope aspect among the physical properties.

Transformation of Forest Road Fill-slope Alignment by Elapsed Years and Physical Properties (임도시공경과년수 및 물리적 인자에 따른 성토사면 선형의 변화)

  • Choi, Yeon Ho;Lee, Joon Woo;Kim, Myeong Jun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.2
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    • pp.47-52
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    • 2000
  • This study was carried out to analyze the effects of elapsed years and physical properties on fill-slope alignment of forest road. For the study, 21 forest roads in Puy$\check{o}$-gun and Asan-shi of Chungchungnam-do were selected and fifteen factors that might influence on fill-slope alignment were analyzed. The major forms of alignment of the fill-slope in the time of construction were concave and compound. But, with the elapsed years, the concave and compound forms have decreased and linear and convex forms have increased. And fill-slope alignment was strongly related with fill-slope distance, fill-slope gradient and ground gradient among the physical properties.

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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)

The Analysis and Forecasting Model for Maintenance Costs Considering Elapsed Years of Old Long-Term Public Rental Housing (노후 장기공공임대주택의 경과 연수별 유지관리비 분석 및 예측 모형)

  • Jung, Yong-Chan;Jin, Zheng-Xun;Hyun, Chang-Taek;Lee, Sanghoon
    • Korean Journal of Construction Engineering and Management
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    • v.23 no.3
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    • pp.83-94
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    • 2022
  • The number of public rental housing has increased according to the government's 「Housing Welfare Roadmap (2017)」, and facility maintenance costs for the demand of improvement of performance and residential standards due to the aging of long-term public housing are significantly increasing. Consequently, the financial burden of public housing rental business for maintaining stocked housing is aggravated. However, there is a lack of objective data to analyze the size of the maintenance costs that are executed by the type of repair work, and the elapsed years of the aged long-term public rental housing. This study analyzes the execution status of 33 long-term public rental housing complexes located in Seoul for 14 to 28 years of elapsed years based on the data of maintenance costs. In addition, this study proposes a model to predict the maintenance costs by elapsed years by dividing 'Long-term Repair Plan Work and Government-Funded Project [Y1]', 'Planned Repair Work and General & Unplanned Repair Work [Y2]', and 'Total maintenance costs [Y3]'. It is intended to be used as basic data for the establishment of the maintenance plan at the stage of setting up the budget and the establishment of the sustainable operation plan for public rental housing

A Study on the Death Cause of the Insured People in Our Company for Recent Three years (최근(最近) 삼년간(三年間) 당사(當社)의 생명보험(生命保險) 가입자(加入者)에 대(對)한 사망현황(死亡現況) 조사(調査))

  • Kim, Dong-Hoon;Ko, Choul-Soo;Kim, Kang-Sueck
    • The Journal of the Korean life insurance medical association
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    • v.3 no.1
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    • pp.269-273
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    • 1986
  • We have examined 5,304 cases of claims by death that had occured for recent three years from January, 1983 to November, 1985 in Dae han kyoyuk Ins. Co. As a result, we came to following conclusions: 1. The total numbers of the deaths are increased for three years, but the deaths, classifying by medical examinations are decreased. 2. The great part of the death were due to Accident death(27.7%), occupied Number 1, malignant neoplasm(23.9%) Number 2 and Circulatory system disease(23.9%), which were the main canses of death in the insured people. 3. With age, section ranging from 30-39 years of death cases took extremely large portions by 35.2%. 4. For the period elapsed, the deaths within 2 years to ander 3 years, 18.6%, above 6 years, 18.6%, thus the period elapsed was longer more and more as years go. 5. By the deaths of malignant neoplasm, hepatoma in male and gastric cancer in female were important causes of death.

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A study on the Residential Satisfaction and Maintenance Consciousness to the Life Span of Apartment (경년에 따른 공동주택 거주자의 주거환경 만족도 및 관리의식 조사연구)

  • Yoon, Chung-Sook;Shin, Soo-Young;Kim, Soo-Jeong
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2005.11a
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    • pp.43-49
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    • 2005
  • The purpose of this study was to provide the fundamental data for the gradual apartment management plan. Through the questionnaire survey, residential satisfactions and maintenance consciousness were investigated. As the result of statistic analysis, the residents' needs for improvement according to the life span of apartment communities were found out. And we can also compare the differences about maintenance consciousness to the life span of apartment. The major research findings are as follows. First, the satisfaction averages according to the life span of apartment communities were classified two groups, less than 10 years' and over than 10 years'. By the requirement for improvement according as the life span apartment communities, habitability factors was demanded in less tham 10 years' group and safety factors was required in over than 10 years' group, Second, dwellers have high preference about remodeling to reconstruction. Especially we have to pay attention to the result that positive consciousness of remodeling and long term reparative marked highly in the group which has the short elapsed years. These results represent the possibility gradual step-by-step remodeling. In other words, the object of remodeling is not only odeteriorated apartments but also new apartments to have short elapsed years.

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Rainfall Pattern Regulating Surface Erosion and Its Effect on Variation in Sediment Yield in Post-wildfire Area (산불피해지에 있어서 강우패턴에 따른 침식토사량의 변화)

  • Seo, Jung-Il;Chun, Kun-Woo;Kim, Suk-Woo;Kim, Min-Sik
    • Journal of Korean Society of Forest Science
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    • v.99 no.4
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    • pp.534-545
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    • 2010
  • To examine 1) rainfall pattern (i.e., type and intensity) regulating surface erosion on hillslopes in postwildfire area and 2) its effect on variation in sediment yield along the gradient of severity wildfire regimes and elapsed years, we surveyed the amount of sediment yield with respect to daily or net-effective rainfall in 9 plots in eastern coastal region, Republic of Korea. Before field investigation, all plots classified into three groups: low-, mixed- and high-severity wildfire regimes (3 plots in each group). We found that, with decreasing wildfire regimes and increasing elapsed years, the rainfall type regulating surface erosion changed from daily rainfall to net-effective rainfall (considering rainfall continuity) and its intensity increased continuously. In general, wildfires can destroy the stabilized forest floors, and thus rainfall interception by vegetation and litter layer should be reduced. Wildfires can also decrease soil pores in forest floors, and thus infiltration rates of soil are reduced. These two processes lead to frequent occurrence of overland flows required to surface erosion, and sediment yields in post-wildfire areas should increase linearly with increasing rainfall events. With the decreasing severity wildfire regimes and the increasing elapsed years, these processes should be stabilized, and therefore their sediment yields also decreased. Our findings on variations in sediment yields caused by the wildfire regimes and the elapsed years suggest understanding of hydrogeomorphic and ecologic diversities in post-wildfire areas, and these should be carefully examined for both watershed management and disaster prevention.

화재감지기의 경년도에 상관한 감응특성 실험.연구

  • Lee, Bok-Yeong;Yu, In-Ho
    • Fire Protection Technology
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    • s.16
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    • pp.13-19
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    • 1994
  • An Experimental study on the relation between responsiveness and elapse of years This experiment study is to appraise a fire detector's durability & reliability. Fire detector is located in office, temp range 10-27 고 65 15%, installed in the ceiling with power on. This is the experiment report of elapsed 5 years.

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EPET-WL: Enhanced Prediction and Elapsed Time-based Wear Leveling Technique for NAND Flash Memory in Portable Devices

  • Kim, Sung Ho;Kwak, Jong Wook
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.5
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    • pp.1-10
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    • 2016
  • Magnetic disks have been used for decades in auxiliary storage devices of computer systems. In recent years, the use of NAND flash memory, which is called SSD, is increased as auxiliary storage devices. However, NAND flash memory, unlike traditional magnetic disks, necessarily performs the erase operation before the write operation in order to overwrite data and this leads to degrade the system lifetime and performance of overall NAND flash memory system. Moreover, NAND flash memory has the lower endurance, compared to traditional magnetic disks. To overcome this problem, this paper proposes EPET (Enhanced Prediction and Elapsed Time) wear leveling technique, which is especially efficient to portable devices. EPET wear leveling uses the advantage of PET (Prediction of Elapsed Time) wear leveling and solves long-term system failure time problem. Moreover, EPET wear leveling further improves space efficiency. In our experiments, EPET wear leveling prolonged the first bad time up to 328.9% and prolonged the system lifetime up to 305.9%, compared to other techniques.