• Title/Summary/Keyword: 안정성 지수

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금리와 물가간의 인과관계 ("깁슨의 역설")분석 : VAR 및 VARMA 모형분석

  • Nam, Ju-Ha;Park, Jae-Cheol
    • The Korean Journal of Financial Management
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    • v.10 no.2
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    • pp.161-179
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    • 1993
  • 본 논문은 벡터자기상관(VAR) 모형과 벡터자기상관이동평균(VARMA) 모형을 사용하여 명목금리와 물가(도매물가)사이의 동태적 관계를 분석한다. 명목금리와 물가사이의 정(+)의 상관관계는 소위 $\ulcorner$깁슨의 역설$\lrcorner$로 불리워지고 있는데, 실증분석 결과에 의하면 한국의 경우 깁슨의 역설은 존재하지 않는 것으로 보여진다. 과거의 많은 연구들이 $\ulcorner$깁슨의 역설$\lrcorner$을 지지하는 실증결과들을 발견한 것은 관련변수들의 안정성(stationarity)을 고려치 않은 것으로 판단된다. 본 논문에서처럼 관련변수들의 안정성을 얻기위해 수준변수(예를들면, 도매물가지수) 대신에 차분되거나 증가율을 사용하고, 금리 및 물가이외에 두변수에 영향을 줄 수 있는 변수(예를들면, 통화변수)들을 포함하는 다변수 모형을 이용한다면 우리나라에서는 $\ulcorner$깁슨의 역설$\lrcorner$은 발견되지 않은 것으로 보여진다. 즉, 회사채 수익율과 도매물가상승율을 명목금리와 물가변수로 각각 사용하고, $1972.III{\sim}1991.III$사이의 분기별 자료를 대상으로 분석한 결과, 두변수 사이의 관계는 일방적 인과관계보다는 독립적인 관계로 나타나고 있다.

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Development and assessment of water management resilience of mid-small scale tributaries (지류 중소하천의 물관리 탄력성 평가지수 개발 및 평가)

  • Park, Jung Eun;Lee, Eul Rae;Lim, Kwang Suop
    • Journal of Korea Water Resources Association
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    • v.49 no.2
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    • pp.95-106
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    • 2016
  • Water Management Resilience Index (WMRI) was developed as a policy measure of adaptability to withstand water stresses and to set up water management strategies mainly in mid-small scale tributaries, and then evaluated on 117 sub-basins in South Korea. The index consists of 3 sub-indices such as vulnerability, robustness and redundancy sub-indices, each including indicators of 3 sectors: water use, flood mitigation, and river environment. Total number of indicators selected for the index was 31. Taking into account the stream order and control capability of river flow discharge, sub-basins were categorized into 3: 1 for mainstreams of lower large dams, 2 and 3 for tributaries, respectively without and with flow discharge regulation. As a result of the evaluation, resilience index scores in Category 2 and 3 are much lower than that of Category 1, especially with very poor score of redundancy. Although there was no significant difference between mainstream and tributaries in vulnerability and robustness sub-indices, results of redundancy sub-index in tributaries were lower than those in mainstream. Thus, it is conceived that the variety of water management schemes should be considered to improve their resilience in the face of future uncertainty. Addressing comprehensive stability of river basin against internal and external impacts, WMRI in this study can also be used for the prioritization of water management plans.

The impact of convergence balance training and taping on spasticity and balance ability in patients with chronic stroke (균형훈련과 테이핑 융복합 적용이 뇌졸중 환자의 발목관절 경직 및 균형능력에 미치는 영향)

  • Park, Shin-Jun;Kim, Tae-Hyun;Go, Jun-Hyeok;Youn, Pong-Sub
    • Journal of Digital Convergence
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    • v.15 no.7
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    • pp.297-306
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    • 2017
  • The study was performed to determine the impact of the gastrocnemius taping with balance training on spasticity and balance ability of the ankle joint. A total of 25 stroke subjects were divided into two groups: a taping with balance training (n=14), a sham taping with balance training (n=11). Spasticity assesment was scored by modified ashworth scale. Balance ability assesment was performed by functional reach test (FRT), the timed up & go test (TUG). The stability index (SI), the left-right weight distribution (left-right WD), the toe-heel weight distribution (toe-heel WD) were analyzed in the eyes open conditions(EO) and eyes closed conditions(EC) conditions using by the Tetrax interactive balance system. The experimental group showed a significant improvement in SI, left-right WD and toe-heel WD in the EO and EC, MAS, FRT, TUG. In comparison between the groups, a significant improvement was detected in FRT, TUG, SI and left-right WD in the EO, and left-right WD and toe-heel WD in the EC. It was found out that a short period of balance training with taping is effective on spasticity and balance ability in stroke patients. Therefore, any stroke patient without skin damage is encouraged to use the gastrocnemius taping for balance rehabilitation.

Spousal Dissimilarity in Age and Education and Marital Stability among Transnational Couples in Korea: A Test of the Transnational Openness Hypothesis (국제결혼 부부의 연령 및 교육수준 격차와 결혼안정성: 국제결혼개방성 가설의 검증)

  • Kim, Doo-Sub
    • Korea journal of population studies
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    • v.35 no.1
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    • pp.1-30
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    • 2012
  • This study explores the effects of spousal dissimilarity on marital stability among transnational couples in Korea. Utilizing micro-data from the 2009 Korean National Multi-culture Family Survey, this paper examines whether formation of transnational marriage generally involves positive assortative matching on age and education. Indices of age dissimilarity and educational dissimilarity are calculated for each country of origin of the foreign wife, and their relationships to the average duration of marriage are analyzed. This study also conducts a micro-level analysis of whether age and educational dissimilarity between spouses helps explain variations in marital duration and probability of getting divorced. Results show greater incidences of spousal dissimilarity in age and educational attainment among transnational couples, which supports the transnational openness hypothesis proposed in this paper. The extant hypothesis that spousal dissimilarity increases the risk of marital dissolution and shortens the duration of marriage is not found to fit transnational couples in Korea.

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The Development of Rail-Transport Operation Control based on Unsaturated Soil Mechanics Concept (불포화토이론을 이용한 강우시 열차운전규제기준 개발)

  • Kim, Hyun-Ki;Shin, Min-Ho;Kim, Soo-Sam
    • Journal of the Korean Society of Hazard Mitigation
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    • v.4 no.1 s.12
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    • pp.25-31
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    • 2004
  • Infiltration of rainfall causes railway embankment to be unstable and may result in failure. Basic relationship between the rainfall and stability of railway embankment is defined to analyze the stability of embankment by rainfall. An experimental study for defining of infiltration rate of rainfall into slope is conducted in the lab. The results of Rainfall Infiltration show that rainfall Infiltration is not equal to infiltration as like reservoir because rate of rainfall infiltration is controlled by slope angle. Based on these results, boundary condition of rainfall is altered and various numerical analysis are performed. The variation of shear strength, the degree of saturation and pore-water pressure for railway slope during rainfall can be predicted and the safety factor of railway slope can be expressed as the function of rainfall amount, namely rainfall index. Therefore, it is judged that this rainfall index can be a good tool for the rail-transport operation control.

Slaking Characteristics of shale in the Gyoungsang Super-group, Korea (경상누층군 셰일의 내구성 특성)

  • Park, Sung-Sik;Ye, Sung-Ryol;Kim, Gyo-Won
    • The Journal of Engineering Geology
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    • v.26 no.3
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    • pp.315-324
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    • 2016
  • Because of a fissility characteristics of shale in the Gyoungsang super-group, it breaks down to debris when daylighted by construction work and causes a slope unstability. To assess the durability property of shale, a series of slake durability tests was conducted by controlling test conditions such as shape of specimen, number of specimen, revolution speed, revolution number, drying temperature and pH of submerging liquid. For the specimen shape, cube one showed relatively lower durability index than cuboid and/or fan shape one. The test with the more number of specimens showed the less durability index because of a higher friction among specimens in the drum. The durability index is linearly decreased by increasing the total number of revolution, while the revolution velocity could not affect the index. And the durability index is also decreased by increasing the drying temperature of specimen and by decreasing the pH of submerging liquid. Because the durability index of shale is almost similar to that of crystalline rocks, the disintegration characteristics of shale could not be assessed by the slake durability test recommended by ISRM, and thus a new test method by changing the total revolution number may be required for the shale having fissility characteristics.

The Analysis of Drainage Time and Resolution of the Quasi-dynamic and Dynamic Wetness Index (배수시간과 격자크기와 반동력학적 또는 동력학적 습윤지수에 대한 연구)

  • Kim, Sang-Hyun;Han, Ji-Young;Lee, Ga-Young;Kim, Nam-Won
    • Journal of Korea Water Resources Association
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    • v.36 no.6
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    • pp.949-960
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    • 2003
  • The resolution issue of wetness index with relaxation of the steady state assumption is explored on the platform of Digital Elevation Model (DEM). The variabilities of the quasi-dynamic wetness index and the dynamic wetness index are discussed on the base of the spatial and statistical aspects depending upon resolutions of DEM and the drainage time. The organization patterns of the wetness index can be observed upon various drainage times and pixel size. The transient behaviour of wetness patterns of the Sulmachun watershed are shown in the relatively short drainage time. The statistical analysis of the quasi-dynamic and dynamic wetness analysis provide the convergence of analysis results to the steady state characteristics later than 10,000 hours drainage time. The probability density functions of the quasi-dynamic and the dynamic wetness index shows the existence of the threshold pixel size of DEM which provide stability and consistency in the computation result of these two wetness index.

Mobility Stabilization of a $6\times6$ Robot Vehicle by Suspension Kinematics Reconfiguration (현가장치 기구 재구성에 의한 $6\times6$ 로봇차량의 기동성 안정화)

  • Baek, W.K.;Lee, J.W.
    • Journal of Power System Engineering
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    • v.14 no.3
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    • pp.39-45
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    • 2010
  • The dynamic stability of a robot vehicle can be enhanced by the Force-Angle Stability Margin concept that considers a variety of dynamic effects. To evaluate the robot vehicle stability, a SPI(stability performance index), which is a function of the suspension arm angles, was used. If the SPI has a minimum value, the robot vehicle has maximum stability. The FASM and SPI concepts were incorporated in the mobility simulation by using ADAMS and MATLAB/Simulink. The simulation results using these concepts showed significant improvements of the vehicle stability on rough terrains.

II. 윤활기유 공정 및 제품소개

  • 이두원
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1986.06a
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    • pp.10-20
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    • 1986
  • I. 윤활기유 제조시설소개 개요 1) 고급 윤활기유(HVI)생산공장으로서 그간 수입에만 의존하던 최고급 품질의 기유를 국내 수요업체에 안정공급 2) 세계 최신 공정인 Gulf Lube Oil Hydrotreating Process Type III (수소첨가 개질공정)채택 3) 국내 최초일뿐 아니라, 세계에서도 일본, 카낟에 이어 3번째로 건설 1. 고품질 제품 생산-고점도 지수, 산화안정성 및 열안정성 우수, 잔류탄소분, 윤황분, 질소분 극소, 방향족 성분 및 회분 극소, 색상 양호 2. 첨가제(특히 산화방지제 및 점도 지수 향상제)사용효과 상승으로 완제품 생산시 생산비 감소 3. 동일 VI 제품 생산기준 수율이 높음 - Hydrocarbon Structure 변화로 원료 유중 부적합성분의 윤활기유화 4. Severity 조절로 Production Mode 변경 용이 5. 양질의 부산물 생산 - HDT Naphtha, Middle distillate 6. 용제 추출기유는 원유종류 및 성상에 따라 제품특성이 결정되나, 사용가능 원유가 다양 하면서도 제품특성 및 품질이 일정함.

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Reliability Analysis of Cantilever Retaining Wall Using Multiple Failure Modes (다중거동함수에 의한 T형 옹벽의 신뢰도 해석)

  • Park, Chun-Su;Song, Yong-Seon;Kim, Yeong-Pil
    • Geotechnical Engineering
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    • v.4 no.2
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    • pp.15-24
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    • 1988
  • To identify the stability of cantilever retaining wall in safe state by the deterministic method, these potential modes of such geotechnical failures as bearing capacity, horizontal sliding and overturning are analysed using Advanced First Order Second Moment (AFOSM) method. All design variables are assumed of the normal distribution and to be statistically independent. Considering the correlations between the single modes, structural system reliability index is 2. 05. Even if the safety factors are larger than the required value in the codes' by the conventional deterministic method, the system reliability of this structure may not be Judged to be safe state since the system reliability index is much lower than general value of 3.

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