• 노동경제논집
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• 제22권2호
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• pp.243-262
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• 1999

This paper demonstrates both theoretically and empirically that there are industry-specific factors as well as the cyclical ones that affect quit and layoff incidences and that the industry-specific effects are positively correlated between the two incidences across industries while the cyclical effects are negatively correlated over time. We first set up a theoretical model to analyze how its parameters affect quits and layoffs through the corresponding change in the optimal wage for the employer and the worker, and then derive from the theoretical separation behaviors the two testable hypotheses - that quits and layoffs are positively correlated to each other across industries, and that quits move procyclically while layoffs move countercyclically. We analyze the two sets of data, BLS establishment data on turnover rates and PSID, to empirically test and confirm each of the two hypotheses.

• Steel and Composite Structures
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• 제14권1호
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• pp.41-55
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• 2013

Fiber reinforced polymers (FRP) materials are increasingly being used for strengthening and repair of steel structures. An issue that concerns engineers in steel members which are retrofitted with FRP is stress experienced due to temperature changes. The changing temperature affects the interface bond between the FRP and Steel. This research focused on the effects of cyclical thermal loadings on the interface properties of FRP bounded to steel members. Over fifty tests were conducted to investigate the thermal effects on bonding between FRP and steel, which were cycled from temperature of $-11^{\circ}C$ ($12^{\circ}F$) to $60^{\circ}C$ ($140^{\circ}F$) for 21-36 days. This investigation consisted of two test protocols, 1) the tensile test of epoxy resin, tack coat, FRP and FRP-steel plate, 2) tensile test of each FRP compound and FRP with steel after going through thermal cyclic loading. This investigation reveals an extensive reduction in the composite's strength.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.178-183
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• 2014

This paper presents a motor characteristics analysis method using an equivalent circuit. Motor characteristics analysis via equivalent circuit is very important for designing a high efficiency single phase induction motor. The accuracy of the motor characteristics depends on the accuracy of the parameters, especially saturation factor, which determines the cyclical relationship in the analysis process. Therefore, using the proposed method, the saturation factor was calculated using the iteration routine and numerical technique. The proposed method was verified by comparing the finite element method results and the dynamo test results of manufactured prototype model.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.546-554
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• 2023

The cyclical behavior of Alloy 617 was examined at 25 ℃ and high temperatures of 800, 850, 900, and 950 ℃ in air to obtain its fatigue life curves. The specimens tested at 25, 800, and 850 ℃ cyclically hardened, whereas those tested above 900 ℃ cyclically softened from the first cycle, that is, their fatigue life was reduced at high temperatures owing to loss of strength. Parameters of the typical Coffin-Manson-Basquin relationship were determined for each test temperature. Interestingly, no significant difference in fatigue life was observed for the specimens tested in the range of 800-950 ℃. Owing to the similarity in fatigue life, we determined fatigue strength and fatigue ductility exponents that could be applied for this temperature range. The parameters obtained were close to the universal slopes, although the fatigue ductility exponent was slightly different. The proposed fatigue life curves were compared with those presented in ASME code.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1088-1096
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• 2008

Data from milk performance testing were used to analyze genetic and environmental trends for purebred Tsigai, Improved Valachian and Lacaune sheep. 103,715 (Tsigai), 212,962 (Improved Valachian) and 2,196 (Lacaune) test-day records gathered by the State Breeding Institute of the Slovak Republic entered the analyses. The respective pedigree data comprised 23,724 (Tsigai), 51,401 (Improved Valachian) and 438 (Lacaune) records. The multiple-trait, mixed model methodology was used to predict the breeding values for daily milk yield, fat and protein content and to estimate the fixed and remaining random effects assumed to affect the above mentioned traits, separately for each breed. The breeding values for daily milk yield were adjusted for 150-day standardized lactation length by multiplying with the constant 150, as the breeding goal of the selection scheme in Slovakian sheep is to increase 150-day milk production and constant heritability throughout the whole lactation is assumed. The genetic trends were expressed as changes in averages of breeding values across birth years of animals. For Tsigai and Lacaune breeds, cumulative genetic changes over the analyzed period were 3.8 and 5.1 kg for 150-day milk, 0 and -0.16% for fat content and 0 and -0.12% for protein content. For Improved Valachian breed, either a low (1.6 kg for 150-day milk yield) or zero (fat and protein content) cumulative genetic change was found. The environmental trends were calculated as averages of solutions for flock-test day effect across years and months in which measurements were taken. A distinctive cyclical pattern which reflected short-time variation in milk production traits was found. Possible explanations for this phenomenon are given and discussed.

• The Journal of Korean Physical Therapy
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• 제17권1호
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• pp.108-122
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• 2005

The gait training strategy in very important things for central nervous system(CNS) injury patients. There are many method and strategy for regaining of the gait who had CNS injury. A human being has central pattern generator(CPG) is spinal CPG for locomotion. It is a neural network which make the cyclical patterns and rhythmical activities for walking. Sensory input from loading and hip position is essential for CPG stimulation that makes the central neural rhythm and pattern generating structure. From sensory input, the proprioceptive information facilitate proximal muscles that controlled in voluntarily from cortical level and visual and / or acoustical information facilitate distal muscles that controlled voluntarily from subcortical level. Gait training method can classify that is functional level and structural level. Functional level includ level surface gait, going up and down the stair. It is important to facilitate a guide tempo in order to activate the central pattern generators. During the functional test or functional activities, can point out the poor period in gait that have to be facilitate in structural level. There are many access methods with patient position and potentiality. The methods are using of rhythmic initiation, replication and combination of isotonic with standing position. Clinically using it on weight transfer onto the stance leg, loading response, loading response and pre-swing, terminal stance, up and downwards stairs.

• Advances in concrete construction
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• 제11권2호
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• pp.111-126
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• 2021

Concrete cracking due to brittle tension strength significantly prevents fully utilization of the materials for "flexural-shear failure" type shear walls. Theoretical and experimental studies applying fiber reinforced concrete (FRC) have achieved fruitful results in improving the seismic performance of "flexural-shear failure" reinforced concrete shear walls. To come to an understanding of an optimal design strategy and find common performance prediction method for design methodology in terms to FRC shear walls, seismic performance on shear walls with PVA and steel FRC at edge columns and plastic region are compared in this study. The seismic behavior including damage mode, lateral bearing capacity, deformation capacity, and energy dissipation capacity are analyzed on different fiber reinforcing strategies. The experimental comparison realized that the lateral strength and deformation capacity are significantly improved for the shear walls with PVA and steel FRC in the plastic region and PVA FRC in the edge columns; PVA FRC improves both in tensile crack prevention and shear tolerance while steel FRC shows enhancement mainly in shear resistance. Moreover, the tensile strength of the FRC are suggested to be considered, and the steel bars in the tension edge reaches the ultimate strength for the confinement of the FRC in the yield and maximum lateral bearing capacity prediction comparing with the model specified in provisions.

• 아태비즈니스연구
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• 제14권3호
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• pp.221-240
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• 2023

Purpose - This paper investigates how business cycle impacts on corporate credit spreads since global financial crisis. Furthermore, it tests how the impact changes by the phase of the cycle. Design/methodology/approach - This study collected dataset from Barclays Global Aggregate Bond Index through the Bloomberg. It conducted multi-regression analysis by projecting business cycle using Hodrick-Prescott filtering and various cyclical variables, while ran dynamic analysis of 5-variable Vector Error Correction Model to confirm the robustness of the test. Findings - First, it proves to be statistically significant that corporate credit spreads have moved countercyclicaly since the crisis. Second, It indicates that the corporate credit spread's countercyclicality to the macroeconomic changes works symmetrically by the phase of the cycle. Third, the VECM supports that business cycle's impact on the spreads maintains more sustainably than other explanatory variable does in the model. Research implications or Originality - It becomes more appealing to accurately measure the real economic impact on corporate credit spreads as the interaction between credit and business cycle deepens. The economic impact on the spreads works symmetrically by boom and bust, which implies that the market stress could impact as another negative driver during the bust. Finally, the business cycle's sustainable impact on the spreads supports the fact that the economic recovery is the key driver for the resilience of credit cycle.

• KDI Journal of Economic Policy
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• 제29권1호
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• pp.177-196
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• 2007

본 연구는 30개 OECD 회원국과 7개 아시아 국가 은행들의 재무제표를 통해 구축된 불균형 패널자료를 이용하여 은행 자기자본의 경기순환적 패턴을 살펴본 것이다. 특히 은행의 잉여자본과 경기순환 간의 관계가 다른 자기자본 결정요인들의 영향을 고려한 후에도 국가 그룹별로 체계적인 차이를 나타내는지를 분석하였다. 실증분석 결과, 선진국 은행들에서는 잉여자본과 경기순환 간에 양(+)의 상관관계가 있으며, 아시아 개도국 은행들에서는 잉여자본과 경기순환 간에 음(-)의 상관관계가 있는 것으로 나타났다. 이는 신바젤자기자본협약(Basel II)이 도입될 경우 개도국에서 경기의 변동성이 더욱 확대될 가능성이 높음을 시사한다. 본 연구는 이와 같은 분석을 바탕으로 은행대출의 경기순응성문제를 완화하기 위한 감독정책 방안들을 점검하였다.

• 한국콘텐츠학회논문지
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• 제16권2호
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• pp.129-142
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• 2016

본 연구는 유휴공간의 재생에 대한 부문별 효과를 평가하여 주민 삶의 질과 지역경제 활성화에 어떠한 영향 관계 및 구조를 가지고 있는지 알아보기 위한 목적으로 분석하였다. 연구가설 설정에 대한 적합성과 통계적 유의성 분석을 통해 전체 총 11개의 가설 중 8개의 가설을 PLS 구조모형을 통해 검증하였다. 그 결과를 크게 3가지로 요약할 수 있는데 첫째, 유휴공간의 재생을 통해 거주민의 삶의 질과 지역경제 활성화를 동시에 만족하려면 물리적, 사회적, 문화적 차원에 대한 부문을 기본적으로 고려해야 한다. 둘째, 유휴공간 환경적 차원의 재생은 지자체 차원에서 주도해야 하며, 관 민 협업을 통해 유휴공간의 재생에 대한 효과가 지역경제 활성화로 이어질 수 있도록 해야 한다. 마지막으로 유휴공간의 재생을 통해 주민 삶의 질의 향상을 도모하고 이러한 만족이 다시 지역경제 활성화로 이어지는 순환적 효과로 이어지도록 해야 한다. 본 연구를 통해 유휴공간의 재생의 이론적 기반을 마련하고 이에 대한 영향구조모형에 대한 실증연구로 의의가 존재한다.