• Title/Summary/Keyword: Downward method

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Numerical Simulation for Tsunami Force Acting on Onshore Bridge (for Solitary Wave) (연안교량에 작용하는 지진해일파력에 관한 수치시뮬레이션(고립파의 경우))

  • Lee, Kwang-Ho;Woo, Kyung-Hwan;Kim, Do-Sam;Jeong, Ik-Han
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.29 no.2
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    • pp.92-108
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    • 2017
  • Present work shows a numerical method to analysis of interaction analysis between solitary wave and onshore bridge. Numerical simulation is carried out by TWOPM-3D (three-dimensional one-field model for immiscible two-phase flows), which is based on Navier-Stokes solver. To do this, the solitary wave is generated numerically in numerical wave channel, and numerical results and experimental results were compared and analyzed in order to verify the applicability of force acting on an onshore bridge. From this, we discussed precisely the characteristics of horizontal and vertical forces (uplift and downward forces) changes including water level and velocity changes due to the variation of solitary wave height, water depth, onshore bridge's location and type, and number of girder. Furthermore, It is revealed that the maximum horizontal and vertical forces acting on the girder bridge show different varying properties according to the number of girder, although each maximum force acting on the girder bridge is proportional to the increasement of incident solitary wave height, and the entrained air in the fluid flow affects the vertical force highly.

Two-dimensional Numerical Simulation of Rainfall-induced Slope Failure (강우에 의한 사면붕괴에 관한 2차원 수치모의)

  • Regmi, Ram Krishna;Jung, Kwan-Sue;Lee, Gi-Ha
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.34-34
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    • 2012
  • Heavy storms rainfall has caused many landslides and slope failures especially in the mountainous area of the world. Landslides and slope failures are common geologic hazards and posed serious threats and globally cause billions in monetary losses and thousands of casualies each year so that studies on slope stability and its failure mechanism under rainfall are being increasing attention of these days. Rainfall-induced slope failures are generally caused by the rise in ground water level, and increase in pore water pressures and seepage forces during periods of intense rainfall. The effective stress in the soil will be decreased due to the increased pore pressure, which thus reduces the soil shear strength, eventually resulting in slope failure. During the rainfall, a wetting front goes downward into the slope, resulting in a gradual increase of the water content and a decrease of the negative pore-water pressure. This negative pore-water pressure is referred to as matric suction when referenced to the pore air pressure that contributes to the stability of unsaturated soil slopes. Therefore, the importance is the study of saturated unsaturated soil behaviors in evaluation of slope stability under heavy rainfall condition. In an actual field, a series of failures may occur in a slope due to a rainfall event. So, this study attempts to develop a numerical model to investigate this failure mechanism. A two-dimensional seepage flow model coupled with a one-dimensional surface flow and erosion/deposition model is used for seepage analysis. It is necessary to identify either there is surface runoff produced or not in a soil slope during a rainfall event, while analyzing the seepage and stability of such slopes. Runoff produced by rainfall may result erosion/deposition process on the surface of the slope. The depth of runoff has vital role in the seepage process within the soil domain so that surface flow and erosion/deposition model computes the surface water head of the runoff produced by the rainfall, and erosion/deposition on the surface of the model slope. Pore water pressure and moisture content data obtained by the seepage flow model are then used to analyze the stability of the slope. Spencer method of slope stability analysis is incorporated into dynamic programming to locate the critical slip surface of a general slope.

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Development and Validation of Korean-version of Classism Attitude Scale(K-CAS) for College Students (대학생용 계층차별주의 태도 척도 개발 및 타당화)

  • Shin, Yun-Jeong;Kim, Eunha;Lee, Eun Sul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.605-621
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    • 2019
  • The purpose of this study was to develop and validate the Korean version of the Classism Attitude Scale for college students (K-CAS) that measures stereotypes and prejudices about socioeconomic class(SES). In study 1, preliminary items were developed through reviewing classism related theories and literatures, analyzing qualitative data by using Consensus Qualitative Method-modified(CQR-M) and getting experts' consultation. With 440 college students data, exploratory factor analysis and reliability analysis were conducted with 14 items in study 1. In study 2, a confirmatory factor analysis and validity analysis were conducted with 400 college students. As a result, two factor structures, upper classism attitude and downward classism attitude, were confirmed. With the higher level of test-retest reliability, the criterion validity was confirmed by the significant correlations among age, subjective SES, the general belief in a just world, negative affects (depression and anxiety), hostility, and K-CAS. The incremental validity was also confirmed that K-CAS scores significantly accounted for 5% of total variation in scores of negative affects(depression and anxiety) in addition to the variables, such as age, subjective SES, house income, and the general belief in the just world. The result of this study is significant in that the developed and validated K-CAS in this study can be a useful tool for further research and prevention and intervention program development related to classism.

Effect of Powder Condition on the Fire and Explosion Characteristics of Suspended and Deposited Dusts (부유 및 퇴적의 분체 조건이 화재폭발 특성에 미치는 영향)

  • Han, Ou-Sup;Seo, Dong-Hyun;Choi, Yi-Rac;Lim, Jin-Ho
    • Korean Chemical Engineering Research
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    • v.60 no.2
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    • pp.229-236
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    • 2022
  • An experimental investigation was conducted on the influences of median size, dust concentration, dust condition (cloud and layer) for the fire and explosion hazard assessment of dusts with the same powder property. For this purpose, tests have been performed in accordance with 20 L explosion sphere, thermogravi- metric analyze, combustion rate tester (UN method). We investigated the explosion characteristics and flame propagation velocity (FPV) in dust cloud and the flame spread velocity(FSV) over dust layer on 8 dust samples with different particle sizes of 4 types of dusts (Sugar, Mg, Al, Zr). An explosion hazard increased with decreasing particle size in Mg and Al dust clouds, but sugar did not show the effect of explosion hazard due to particle size change in dust clouds. The flame propagation velocity (FPV) of suspended dusts increased significantly when the particle size decreased from micro to nano than the variation of particle size in micro range. The flame spread velocity (FSV) over dust layer showed a tendency to increase over the inclined dust layers (30° slope) rather than the horizontal dust layers (0° slope). The flame spread rate (FSV) over dust layers increased on the inclined dust layer (30° slope) rather than the horizontal dust layer (0° slope) and was higher upward flame than the downward flame in condition of inclined dust layers(30° slope).

The Symbolism of Korean 'Gat' and the Etymology of 'Hat' (영어 'Hat'가 된 한국 '갓' 의 상징성)

  • Hyo Jeong Lee;Youngjoo Na
    • Science of Emotion and Sensibility
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    • v.25 no.4
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    • pp.3-20
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    • 2022
  • The origins of the world-recognized Korean gat can be traced back to Gojoseon, and the jades for the sangtu and gwanja come from Hongshan culture. This study examines the etymology of the hat, the symbolism of the gat and the jade comb, and the history of the development of the accessories for the hat. The research methods of literature review, investigation of relics and murals, and analysis of cases of pronunciation changes were used. Most of the relics excavated from the Hongshan are identical to those excavated from Korea. The Byun-Khan people wore a triangle-shaped conical hat (the byun), which was shaped to fit the protruding sangtu hairstyle, with a foldable brim that, if pulled downward, changed the hat to a gat. The Chu sangtu, a pointed top-knot hairstyle, is uniquely found among Northeast Asian peoples, and it is an ethnic symbol for Koreans. Until the modern period, many Koreans wore their hair in the sangtu style, indicating their descent from the sky. Jade combs shaped like birds and clouds from the Hongshan period emphasized the religious nature and ceremony of hair styling at that period. The word hat is widely used to refer to gat all over the world. The pronunciation of ㄱg, ㅎh. and ㅋq/kh are closely related to each other, and the ancient pronunciation ㄱg gradually evolved to ㅎh or ㅋq/kh. The English 'Hat' and Korean 'Gat' were transformed from the middle-ancient sound 'gasa > gosa > got' of the crown 'gwan, gokkal'. This creative hair style culture that started from the Hongshan culture continued to be fashionable during the Gojoseon Dangun period, and the decoration techniques for hats and accessories were inherited over time and continuously developed. Along with the method of making gat, creative hair-related parts, such as manggeons, donggot pins, gwanja buttons, and fine combs were developed over the course of a thousand years.

Synthesis and Characteristic Evaluation of Downward Conversion Phosphor for Improving Solar Cell Performance (태양전지 성능향상을 위한 하향변환 형광체의 합성 및 특성평가)

  • Jae-Ho Kim;Ga-Ram Kim;Jin-To Choi;Soo-Jong Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.523-528
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    • 2023
  • The applicability as a material to improve solar cell performance was reviewed by synthesizing a phosphor that emits red wavelengths by a liquid synthesis method using a metal salt aqueous solution and a polymer medium as a starting material. An aqueous solution was prepared using nitrate of metals such as Ca, Zn, Al, and Eu, and a precursor impregnated with starch, a natural polymer, was sintered to synthesize CaZnAlO:Eu phosphor powder. The surface structure and composition analysis of the synthesized CaZnAlO:Eu phosphor powder were analyzed by scanning electron microscope(SEM) and energy-dispersed X-ray spectroscopy(EDS). The crystal structure of CaZnAlO:Eu phosphor particles was analyzed by an X-ray diffraction analyzer (XRD). As a result of measuring the photoluminescence(PL) characteristics of the phosphor, it was confirmed that a red phosphor with a light emitting wavelength of 650-780nm was successfully synthesized. According to SEM and EDS analysis, the synthesized Ca14Zn6Al9.93O35:Eu3+0.07 phosphor powder has a uniform particle size, and Eu ions used as an activator are present. The synthesized CZA:Eu3+ phosphor can be used as a material that can increase the light absorption efficiency of the solar cell by converting ultraviolet or visible light down conversion into a wavelength in the near-infrared region.

An integrated Method of New Casuistry and Specified Principlism as Nursing Ethics Methodology (새로운 간호윤리학 방법론;통합된 사례방법론)

  • Um, Young-Rhan
    • Journal of Korean Academy of Nursing Administration
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    • v.3 no.1
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    • pp.51-64
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    • 1997
  • The purpose of the study was to introduce an integrated approach of new Casuistry and specified principlism in resolving ethical problems and studying nursing ethics. In studying clinical ethics and nursing ethics, there is no systematic research method. While nurses often experience ethical dilemmas in practice, much of previous research on nursing ethics has focused merely on describing the existing problems. In addition, ethists presented theoretical analysis and critics rather than providing the specific problems solving strategies. There is a need in clinical situations for an integrated method which can provide the objective description for existing problem situations as well as specific problem solving methods. We inherit two distinct ways of discussing ethical issues. One of these frames these issues in terms of principles, rules, and other general ideas; the other focuses on the specific features of particular kinds of moral cases. In the first way general ethical rules relate to specific moral cases in a theoretical manner, with universal rules serving as "axioms" from which particular moral judgments are deduced as theorems. In the seconds, this relation is frankly practical. with general moral rules serving as "maxims", which can be fully understood only in terms of the paradigmatic cases that define their meaning and force. Theoretical arguments are structured in ways that free them from any dependence on the circumstances of their presentation and ensure them a validity of a kind that is not affected by the practical context of use. In formal arguments particular conclusions are deduced from("entailed by") the initial axioms or universal principles that are the apex of the argument. So the truth or certainty that attaches to those axioms flows downward to the specific instances to be "proved". In the language of formal logic, the axioms are major premises, the facts that specify the present instance are minor premises, and the conclusion to be "proved" is deduced (follows necessarily) from the initial presises. Practical arguments, by contrast, involve a wider range of factors than formal deductions and are read with an eye to their occasion of use. Instead of aiming at strict entailments, they draw on the outcomes of previous experience, carrying over the procedures used to resolve earlier problems and reapply them in new problmatic situations. Practical arguments depend for their power on how closely the present circumstances resemble those of the earlier precedent cases for which this particular type of argument was originally devised. So. in practical arguments, the truths and certitudes established in the precedent cases pass sideways, so as to provide "resolutions" of later problems. In the language of rational analysis, the facts of the present case define the gounds on which any resolution must be based; the general considerations that carried wight in similar situations provide warrants that help settle future cases. So the resolution of any problem holds good presumptively; its strengh depends on the similarities between the present case and the prededents; and its soundness can be challenged (or rebutted) in situations that are recognized ans exceptional. Jonsen & Toulmin (1988), and Jonsen (1991) introduce New Casuistry as a practical method. The oxford English Dictionary defines casuistry quite accurately as "that part of ethics which resolves cases of conscience, applying the general rules of religion and morality to particular instances in which circumstances alter cases or in which there appears to be a conflict of duties." They modified the casuistry of the medieval ages to use in clinical situations which is characterized by "the typology of cases and the analogy as an inference method". A case is the unit of analysis. The structure of case was made with interaction of situation and moral rules. The situation is what surrounds or stands around. The moral rule is the essence of case. The analogy can be objective because "the grounds, the warrants, the theoretical backing, the modal qualifiers" are identified in the cases. The specified principlism was the method that Degrazia (1992) integrated the principlism and the specification introduced by Richardson (1990). In this method, the principle is specified by adding information about limitations of the scope and restricting the range of the principle. This should be substantive qualifications. The integrated method is an combination of the New Casuistry and the specified principlism. For example, the study was "Ethical problems experienced by nurses in the care of terminally ill patients"(Um, 1994). A semi-structured in-depth interview was conducted for fifteen nurses who mainly took care of terminally ill patients. The first stage, twenty one cases were identified as relevant to the topic, and then were classified to four types of problems. For instance, one of these types was the patient's refusal of care. The second stage, the ethical problems in the case were defined, and then the case was analyzed. This was to analyze the reasons, the ethical values, and the related ethical principles in the cases. Then the interpretation was synthetically done by integration of the result of analysis and the situation. The third stage was the ordering phase of the cases, which was done according to the result of the interpretation and the common principles in the cases. The first two stages describe the methodology of new casuistry, and the final stage was for the methodology of the specified principlism. The common principles were the principle of autonomy and the principle of caring. The principle of autonomy was specified; when competent patients refused care, nurse should discontinue the care to respect for the patients' decision. The principle of caring was also specified; when the competent patients refused care, nurses should continue to provide the care in spite of the patients' refusal to preserve their life. These specification may lead the opposite behavior, which emphasizes the importance of nurse's will and intentions to make their decision in the clinical situations.

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The Study of Effect and Safety related to Dong-gi Acupuncture(DGA) and Complex therapy on Lumbago due to blood stasis and sprain (좌섬(挫閃)·어혈(瘀血) 요통(腰痛)에 동기침법(動氣鍼法) 및 복합치료(複合治療)의 유효성(有效性) 및 안정성(安定性) 연구(硏究))

  • Kim, Kee-Hyun;Lim, Hyung-Ho;Hwang, Hyeon-Seo;Song, Ho-Sueb;Song, Young-Sang;Kwon, Soon-Jung;Kim, Kyung-Nam;Ahn, Koang-Hyun;Lee, Seong-No;Kang, Mi-Suk;Gyun, Im-Jung
    • Journal of Acupuncture Research
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    • v.19 no.3
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    • pp.107-114
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    • 2002
  • Objective : This study was designed to find the most effective and safest way to overcome Lumbago due to blood stasis and sprain involved in a few Meridian Tendino-musculatures by evaluating the effect of two kinds of Dong-gi(Dong-qi) Acupuncture(DGA) and by reporting their side effects. Material : 97 patients of out and admission patients were selected, who were diagnosed with lumbar sprain caused by repetitive bending, heavy weight lifting, unsuitable posture, concussion and falling down and whose Lumbago due to blood stasis and sprain in the concept of oriental medicine. Methods : 97 patients were divided into three groups. One is exclusive DGA group to which DGA and the method retaining needles on the acupoints for about 20 minutes were applied, the other is DGA combined active exercise group in which patients stretched their Meridian Tendino-muscuIatures with their hips moving up and downward repeatedly during DGA, the third is DGA combined passive exercise group in which patients were made to flex or extend their bodies on the auto flexion-distraction table in a prone position, from 10 to 20 degree, during DGA. In each group, bed rest, physical therapy and herbal medicine were used according to symptoms, in addition to DGA. In DGA method, "Su(Shu)" points of the meridian related to the involved Meridian Tendino-musculature were mainly chosen, that is, Sokkol(Shugu, B65), Hugye(Houxi, SI3), ChungJo(Zhongzhu, TE3) were used, for most LBP belonged to Bladder and Gallbladder Meridian Tendino-musculature disorders. Pyong-Bo-Pyong-Sa(Ping-Bu-Ping-Xie) such as Dong-Gi and Yeom-Jeon(Nian-Zhuan) was applied as Bo-Sa method. For evaluation of effectiveness, new score system was devised by severity of pain and range of movement. the score was given twice at patients' first and last visit and the difference between first and last score was regarded as a evaluation scale, the effectiveness was classified into four grade by evaluation scale.(scale : 12-15; excellent, 8-11; good, 4-7; fair, 0-3; bad) Results : 1. Exclusive DGA, DGA combined active exercise and DGA combined passive exercise group showed 97, 87 and 89% in effectiveness. 2. Exclusive DGA, DGA combined active exercise and DGA combined passive exercise group showed no aggravation of pain, range of movement. 3. In blood test of 34 patients, only one patient showed abnormal rise of sGOT, sGPT and $\gamma$-GTP at his first visit and the others didn't show any detrimental change. DGA had no bad influence upon BUN and creatinine of patients. Conclusion : For complex theraphy combining DGA, exercise, physical therapy and Herbal medicine proved to be highly effective on treating lumbago due to blood stasis and sprain, this is expected to be available for clinical use.

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The Program Development of Nursing Activities for Community Health Promotion (지역사회 건강증진 간호활동의 프로그램 개발)

  • Park, Jeong-Hee
    • Research in Community and Public Health Nursing
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    • v.10 no.2
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    • pp.291-306
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    • 1999
  • Health promotion has come to the fore through new concept approach in consequence of the increase of chronic diseases. increase of medical cost and social trend of putting more emphasis on the individual responsibility for health. Studies of health promotion can be classified into two types: one is micro intervention method which is mainly focused on modifying individual life style and the other. macro intervention method in which they put another emphasis on the environment the individual is surrounded. in addition to modifying individual life style. This study belongs to the later. This study aims to develop nursing activities and program it for the purpose of community health promotion. The process of the study can be briefed as follows: to draw out nursing contents to intervene for community health promotion: to promote community health to develop nursing action indicators; to develop nursing action indicators for the development of main nursing activities. And those developed nursing activities are programmed systematically. The community health promotion program is composed of a hierarchical structure with nursing process that the nurses are supposed to apply to perform professional nursing. the level of nursing perform. the main items of nursing process. health promotion nursing indicators. health promotion nursing activities. The conclusion of this study according to objectives are as follows. First. community health promotion contents at individual and community level are remained revised and complemented and those at organizational level are developed. The developed main contents of community health promotion nursing are as follows. 1) Revised individual level nursing contents: 35 items. 2) Developed organizational level nursing contents: 24 items. 3) Revised community level nursing contents: 36 items. Second. for the development of the health promotion nursing action indicators. principles were set up and applied as follows. 1. Developed indicators should be provided with such qualities as comprehensiveness. diversity. developability, availability. practicability. 2. Developed indicators should be provided with functional abilities to measure the conditions and changes in any phenomena or state. inspect the development of the states. control the implementing program. evaluate the result of program and grasp what nurses should do. 3. Developed indicators should be provided with relevance and sequence. 4. Developed indicators should be undergo inspections from the expert. The developed community health promotion action indicators developed in this study. observing above mentioned principles. are total 330 indicators of 95 items. Third. when the main nursing activities were developed for each nursing action indicator. five priciples were set up in accordance with each nursing action indicators to decide main nursing activities. Main nursing activities developed observing those principles. are total 1273. Forth. for the programming of the developed nursing activities. three principles were set up. 1. The nursing activities are systematized in line with (nursing process) (nursing client) (key items of nursing process) (nursing action indicators for health promotion) (nursing activities). 2. The program is constructed in downward and hierarchical order. 3. The program is constructed not in relation to same level activities but in relation to high and low level activities. The process step of programming of developed main health promotion nursing activities are; Step 1. The Developed nursing action indicators are classified into nursing process. Step 2. The main nursing activities are allocated per each nursing action indicators. Step 3. The statement of main nursing activities are inspected. Step 4. The items of main nursing activities allocated by a certain nursing action indicators are sequenced. taking into consideration the elaborateness of activity. the sequency of activity. familiarity of activity. the difficulty of activity. the interest of activity. the frequency of activity. Step 5. The whole developed program should undergo comprehensive and critical inspections.

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Assessment of Climate Change Impact on Storage Behavior of Chungju and the Regulation Dams Using SWAT Model (SWAT을 이용한 기후변화가 충주댐 및 조정지댐 저수량에 미치는 영향 평가)

  • Jeong, Hyeon Gyo;Kim, Seong-Joon;Ha, Rim
    • Journal of Korea Water Resources Association
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    • v.46 no.12
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    • pp.1235-1247
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    • 2013
  • This study is to evaluate the climate change impact on future storage behavior of Chungju dam($2,750{\times}10^6m^3$) and the regulation dam($30{\times}10^6m^3$) using SWAT(Soil Water Assessment Tool) model. Using 9 years data (2002~2010), the SWAT was calibrated and validated for streamflow at three locations with 0.73 average Nash-Sutcliffe model Efficiency (NSE) and for two reservoir water levels with 0.86 NSE respectively. For future evaluation, the HadCM3 of GCMs (General Circulation Models) data by scenarios of SRES (Special Report on Emission Scenarios) A2 and B1 of the IPCC (Intergovernmental Panel on Climate Change) were adopted. The monthly temperature and precipitation data (2007~2099) were spatially corrected using 30 years (1977~2006, baseline period) of ground measured data through bias-correction, and temporally downscaled by Change Factor (CF) statistical method. For two periods; 2040s (2031~2050), 2080s (2071~2099), the future annual temperature were predicted to change $+0.9^{\circ}C$ in 2040s and $+4.0^{\circ}C$ in 2080s, and annual precipitation increased 9.6% in 2040s and 20.7% in 2080s respectively. The future watershed evapotranspiration increased up to 15.3% and the soil moisture decreased maximum 2.8% compared to baseline (2002~2010) condition. Under the future dam release condition of 9 years average (2002~2010) for each dam, the yearly dam inflow increased maximum 21.1% for most period except autumn. By the decrease of dam inflow in future autumn, the future dam storage could not recover to the full water level at the end of the year by the present dam release pattern. For the future flood and drought years, the temporal variation of dam storage became more unstable as it needs careful downward and upward management of dam storage respectively. Thus it is necessary to adjust the dam release pattern for climate change adaptation.