• Title/Summary/Keyword: long-term change

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A Study on the Repair Time of the Construction Type in the Apartment Housings (공동주택 공종별 수선시기 설정 연구)

  • Lee, Kang-Hee;Park, Geun-Soo;Chae, Chang-U
    • Journal of the Korean housing association
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    • v.22 no.4
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    • pp.83-92
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    • 2011
  • Apartment is settled down as a main housing type and massive supply has been conducted since 1990's. The government has focused on the housing supply to improve the housing number and cut its price. On the contrary, the management of the housing has been neglected to get an early deterioration. Since 1995's, various ways have been made to improve and maintain the building function and performance. Among these, the long-term repair plan has played a main role to manage the housing condition and plan the repair schedule for preparing the massive cost of repair such as a roof proof, elevator change. The long-tern repair plan provides the repair time and repair rate according to various construction types. Most of the management agent apply the repair standard into the field area. But the repair time could not reflect the present condition and bring into the wrong maintenance. Therefore, the repair time for the long-term maintenance plan would be revised and reflected from the material and technology development. |n this study, it aimed at improvement for the repair time in various construction types which are provided in the long-term repair plan. For this, the 22 management agents are surveyed directly. This study shows that the repair time of the painting are correspondent to the repair time of the long-term plan irregardless of the painting materials. Most of other areas would correspondently similar to the long-term plan. This study could not include the building location, material and other haracteristics. Therefore, the further study would be needed to reflect the building and materials attributes to get the detailed repair time.

Prediction of SWAT Stream Flow Using Only Future Precipitation Data (미래 강수량 자료만을 이용한 SWAT모형의 유출 예측)

  • Lee, Ji Min;Kum, Donghyuk;Kim, Young Sug;Kim, Yun Jung;Kang, Hyunwoo;Jang, Chun Hwa;Lee, Gwan Jae;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.29 no.1
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    • pp.88-96
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    • 2013
  • Much attention has been needed in water resource management at the watershed due to drought and flooding issues caused by climate change in recent years. Increase in air temperature and changes in precipitation patterns due to climate change are affecting hydrologic cycles, such as evaporation and soil moisture. Thus, these phenomena result in increased runoff at the watershed. The Soil and Water Assessment Tool (SWAT) model has been used to evaluate rainfall-runoff at the watershed reflecting effects on hydrology of various weather data such as rainfall, temperature, humidity, solar radiation, wind speed. For bias-correction of RCP data, at least 30 year data are needed. However, for most gaging stations, only precipitation data have been recorded and very little stations have recorded other weather data. In addition, the RCP scenario does not provide all weather data for the SWAT model. In this study, two scenarios were made to evaluate whether it would be possible to estimate streamflow using measured precipitation and long-term average values of other weather data required for running the SWAT. With measured long-term weather data (scenario 1) and with long-term average values of weather data except precipitation (scenario 2), the estimate streamflow values were almost the same with NSE value of 0.99. Increase/decrease by ${\pm}2%$, ${\pm}4%$ in temperature and humidity data did not affect streamflow. Thus, the RCP precipitation data for Hongcheon watershed were bias-corrected with measured long-term precipitation data to evaluate effects of climate change on streamflow. The results revealed that estimated streamflow for 2055s was the greatest among data for 2025s, 2055s, and 2085s. However, estimated streamflow for 2085s decreased by 9%. In addition, streamflow for Spring would be expected to increase compared with current data and streamflow for Summer will be decreased with RCP data. The results obtained in this study indicate that the streamflow could be estimated with long-term precipitation data only and effects of climate change could be evaluated using precipitation data as shown in this study.

Long-term Deflection Analysis of Simply Supported PC Beams Considering Steel Effects (PC 단순보의 강재영향을 고려한 장기처짐해석)

  • 이대우;박영식;이재훈;신영식
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.245-250
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    • 1995
  • Steel effects on creep deformation of prestressed concrete structues are investigated by a parametric study. Prestressed steel ratio, Prestressed steel distribution, initial flexural stress gradient, and modular ratio are selected as parameters. Sectional analysis for the beam section of parameter combination is performed to find curvatrue change due to creep. Based on the investigation, long-term curvature formulas from regression analysis are proposed. Application of the furmulas to simply supported prostressed concrete beam shows the effect of steel on deflection.

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Time Course Change in Composition of Ginseng Polyacetylenes (인삼(人蔘) polyacetylene 조성(組成)의 경시변화(經時變化))

  • Han, Byung-Hoon;Song, Byung-Joon;Ro, Hwan-Sung
    • Korean Journal of Pharmacognosy
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    • v.7 no.3
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    • pp.191-193
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    • 1976
  • It has been known that ginseng extract contains several polyacetylene components. But we found only two polyacetylene components in the freshly prepared ginseng extract. Long-term preservation of ginseng or ginseng extract produced many artifact polyacetylenes. The ratio of artifact/genuine polyacetylene was determined by TLC-densitometry on long-term preserved ginseng samples. The results indicated that the ratio was increased proportionally with the span of preservation.

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Long term earth pressure behavior behind stub abutment (난쟁이 교대배면의 장기 토압거동)

  • 박영호;정경자;김낙영;황영철
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.779-786
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    • 2002
  • To find a long term horizontal movement of superstructure caused by seasonal thermal change, several types of gages are installed such as soil earth pressuremeter behind stub abutment and jointmeter between approach slab and relief slab. As results, maximum passive earth pressure behind integral bridge abutments centerline with lateral movement of superstructure is about 1/6 of classic Rankine's earth pressure. And its distribution is not triangular but rectangular shape due to shape behind integral bridge abutments.

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The Change of the Voice Parameters in Long-term Sensorineural Hearing Loss Patients (장기간의 양측 감각신경성 난청환자에서 음성지표의 변화)

  • 윤자복;조경래;정상원;최정환;유영삼;우훈영;이강수
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.12 no.2
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    • pp.140-144
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    • 2001
  • Backgrounds & Objectives : Prolonged hearing loss was considered as one of the factors which have the potential to cause vocal changes. However, the analysis of quality of phonation in hearing loss patients has not been achieved enough. The purpose of the study was to evaluate the difference in objective acoustic parameters between long-term hearing impaired patients and normal control group. Material & Methods : The material of this investigation comprised a group of 20 patients (M : F=10 : 10) with moderate or profound hearing loss(over 50dB). The duration of all hearing loss was over 1 year. All of them underwent the acoustic examinations comprising electroglottography, multidimensional voice program and formant analysis during phonation of the bowels /a/ with free confortable tone and /i/ with voluntary high tone. The results of the acoustic examinations were compared with those of a control group, composed of 20 sex- and age-matched normal hearing subjects. Results : In the male hearing loss subjects, the significant increase was detected in pitch and shimmer during phonation of /a/ and in pitch during phonation of /i/. In addition, this group was characterized by decreased fundamental frequency during phonation of /i/. In female, there was no difference between hearing loss group and normal control group except a decreased formant 1 frequency. Conclusion : Long-term moderate and profound sensorineural hearing loss could affect the objective voice parameters.

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Whether Alzheimer's Disease is Responsive to a Single Oral Dose of Donepezil and this Response is Predictive Factor in Alzheimer's Disease (일회 Donepezil 투약이 알쯔하이머병 환자에 미치는 영향 및 반응군 예측 인자로서의 가능성)

  • Kwak, Yong-Tae;Yang, Young-Soon;Noh, Yong-Woo
    • Korean Journal of Biological Psychiatry
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    • v.18 no.1
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    • pp.36-45
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    • 2011
  • Objectives : Though a proportion of Alzheimer's disease(AD) patients treated with donepezil have shown positive response on cognition, but the responders' characteristics are still uncertain. This study attempts to identify whether a single oral dose of donepezil(5mg) can change cognition and the relationship between single dose responder items and long-term responder are examined. Methods : Twenty-three AD patients for single donepezil challenge study group and eleven AD patients for controls were participated in the study. Seven days after baseline study for neuropsychological test and EEG, same studies were rechecked after donepezil medication in study group. In donepezil study groups, 12 weeks after donepezil medication, neuropsychological test and EEG were rechecked. Results : After single donepezil challenge, forward digit span, Rey-Osterrieth Complex Figure Test copy, SVLT delayed recall were significantly improved, and beta spectra power in anterior, theta spectra power in posterior field were significantly decreased. According to linear regression analysis, forward digit span after single donepezil challenge was significantly positive correlated with long-term responders. Conclusions : This study suggests that single donepezil medication can significantly change cognitive functions and EEG in AD patients. Among these responsive items, forward digit span was significantly correlated with long-term responder.