• 대한조선학회논문집
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• 제43권4호
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• pp.476-483
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• 2006

Fatigue strength assessments with two types of load carrying fillet weldment under out-of-plane bending load have been carried out by using both hot spot stress and structural stress methods. In this study, a derivation for the structural stress method using shell element models is discussed in detail. Finite element analysis using shell element models have been performed for the assessment of fatigue strength. As a result of the fatigue strength evaluation for load carrying transverse fillet weldment, hot spot stress method is found to be consistent with structural stress method and measurement. Hot spot stress, however, estimated for the load carrying longitudinal fillet weldment exhibit large variation with respect to mesh size and element type while the calculated structural stress for the longitudinal fillet weldment is relatively independent of mesh size. On the other hand, drawbacks and doubts associated with applying the structural stress method such as the guidance of virtual node method have been discussed.

• 한국항공운항학회지
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• 제29권3호
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• pp.34-43
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• 2021

Wake turbulence generated by the lead aircraft has a significant impact on the following aircraft and it is has been considered a key factor to consider whenin determining the longitudinal separation between the aircraft. ICAO classifies aircraft into four wake turbulence categories based on the maximum takeoff weight and provides the longitudinal separation minima for each category. Due to richer measured data and better understanding of physical processes, it is raised that classifying aircraft with only four wake turbulence grades is imprecise and leads to over-separation in many instances. In this regards, much research on a new method of classifying Wake Turbulence Category(Re-CAT) has been done by EURO-CONTROL, FAA, and ICAO. The main purpose of this study is to conduct a comparative analysis of the existing wake turbulence separation standards with Re-CAT in terms of departure capacity and the resulting benefits of Re-CAT using the data from the Incheon International Airport. The results show that EUROCONTROL and new ICAO standards have the greater effect on reducing wake turbulence separation, compared to the FAA RE-CAT standards. It is also concluded that Re-CAT presents different results of wake turbulence separation depending on the flight characteristics of each airport.

• 의학교육논단
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• 제16권2호
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• pp.77-87
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• 2014

The purpose of this study was to investigate the influence of demographic data, academic demand, perfectionism, and academic failure tolerance on academic burnout of medical and graduate students at Yeungnam University. A mixed method study was conducted. Fourteen students participated in a focus group interview and 302 students, including 151 medical students and 151 graduate students, completed a survey, which addressed the factors of academic burnout, academic demand, perfectionism, and academic failure tolerance. There were significant differences in the academic burnout by age and year in school. The 2nd year medical & graduate students experienced significantly higher academic burnout than the other students. Multiple regression analysis revealed that academic burnout of medical and graduate students was significantly affected by academic demand (p<0.001), self-oriented and socially-prescribed perfectionism (p<0.001, p<0.01), and feeling and behavior, which were sub-factors of academic failure tolerance (p<0.05, p<0.01). It is suggested that comparative studies with other student groups, a longitudinal study of medical and graduate students, and a prospective study of coping styles and methods of preventing academic burnout need to be conducted.

• Geomechanics and Engineering
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• 제30권6호
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• pp.525-538
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• 2022

This paper presents a more general model for T-shaped combined footings that support two columns aligned on a longitudinal axis and each column provides an axial load and two orthogonal moments. This model can be applied to the following conditions: (1) without restrictions on its sides, (2) a restricted side and (3) two opposite sides restricted. This model considers the linear soil pressure. The recently published works have been developed for a restricted side and for two opposite sides restricted by Luévanos-Rojas et al. (2018a, b). The current model considers the uniform pressure distribution because the position of the resultant force coincides with the center of gravity of the surface of the footing in contact with the soil in direction of the longitudinal axis where the columns are located. This paper shows three numerical examples. Example 1 is for a T-shaped combined footing with a limited side (one column is located on the property boundary). Example 2 is for a T-shaped combined footing with two limited opposite sides (the two columns are located on the property boundary). Example 3 is for a T-shaped combined footing with two limited opposite sides, one column is located in the center of the width of the upper flange (b₁/2=L₁), and other column is located at a distance half the width of the strip from the free end of the footing (b₂/2=b-L₁-L). The main advantage of this work over other works is that this model can be applied to T-shaped combined footings without restrictions on its sides, a restricted side and two opposite sides restricted. It also shows the deficiencies of the current model over the new model.

• 대한간호학회지
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• 제7권1호
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• pp.1-9
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• 1977

Primary function of health record is that as tool of communication between the health processionals with the mutual goal, the promotion of health care standard. Studies have been carried out world over oil tile subject, among those, Weed's Problem-Oriented Health Record is considered a paramount achievement. This study was designed to assess tile possibility of implementing tile problem-oriented health record system through ail experiment in order to provide data for nurse administrators infiltrating reformation of recording system and format. Record of 29 patients admitted at Korea University Hospital, Seoul, from March through June, 1976 for 4 to 14 days were sampled. Nursing notes were recorded by research assistants; senior nursing student trailed extensively by the researcher oil Problem-Oriented Records, oil Problem Oriented Nursing Record format (experimental group) and analysis were carried out comparative, with that of traditional nursing records noted by other nursing personnel (control group) on the same patient. Attitude towards Problem Oriented Nursing Record system and format were attained through questionaries responded by the 51 research assistants. Results are as fellows: Comparative analysis revealed that: 1. Assessment of patients' health problems recorded significantly more in traditional records. 2. Focus of health Problem differed; traditional records slowed significantly higher frequency in medical and procedure as focus while problem oriented records on nursing focus problems. 3. Problem- Oriented records were better organized, Mean value scores of attitude towards Problem- Oriented Records revealed that: Positive value scores on all 4 categories: 1) Assessment of nursing needs, 2) Nursing care planning 3) Patient progress assessment and 4) Tool of teaching and learning revealed that the Problem-Oriented Nursing Record is positively accepted by tile respondents. Recommendation Further experiments on implementation of Problem- Oriented Health Record are recommended: experiment involving all health professionals, in larger scope and longitudinal.

• 상하수도학회지
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• 제20권6호
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• pp.911-918
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• 2006

This study was conducted to evaluate the effect of the launder type on settling performance and hydrodynamic behavior within the two certain full-scale sedimentation basins (each flow rate/one basin; $10,000m^3/d$); one is the transverse typed launder(existing basin) and the other is building the finger type launder in combination with the longitudinal baffle. Comparative experimental investigations have been carried out through residual turbidity and particle concentration measurements in each effluent from two basins with the transverse and the finger type launders, respectively. From the experimental results, we could observe that turbidity removal rate in the finger type launder basin (modified basin) is about 30% higher than that in the transverse type launder basin (existing basin). Also, from the measurement of total particle concentration in each effluent, the removal efficiency was improved about 27% within modified basin compared to the existing basin. In order to explain the comparative experimental results and investigate the hydridynamic behavior within each basin in more detail, we conducted computational fluid dynamics (CFD) simulation and verified simulation results with acoustic Doppler velocimetry (ADV) technique. From the CFD simulation, it was investigated that extreme upward flow occurs underneath of the transverse launder. On the other hand, in the case of modified basin, the upward flow, which occurred in the beneath of launder, was much less than that in the existing basins.

• Structural Engineering and Mechanics
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• 제68권4호
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• pp.485-495
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• 2018

This paper presents the results of an experimental study on the structural performance of an innovative GFRP-concrete composite beam construction, which is reinforced with longitudinal GFRP pultruded box-profile and transverse steel stirrups. GFRP perfobond (PBL) shear connectors are employed to enhance the bonding performance between the GFRP profile and the concrete portion. To investigate the shear and flexural performance of this composite system, eight specimens were designed and tested under three-point and four-point bending. The main variables were the height of the composite beam and the shear span-to-depth ratio. The test results indicated that bonding cracks did not occur at the interface between the GFRP profile and the concrete until the final stage of the test. This shows that the specimens performed well as composite beams during the test and that the GFRP PBL connectors were reliable. Based on the test results, two calculation methods were used to determine the flexural and shear capacity of the composite beams. A comparative study of the test and theoretical results suggests that the proposed methods can reasonably predict both the flexural and shear capacities of the specimens, whereas the provisions of ACI 440 are relatively conservative on both counts.

• 한국해양공학회지
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• 제29권1호
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• pp.28-33
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• 2015

The icebreaking research vessel ARAON had her second ice trial in the Arctic Ocean from July 16 to August 12, 2010. In this study, the ice loads measured during the “general” operation and “ice breaking” operation in ice-covered waters were analyzed and compared. Whereas the “general” operation stands for the voyage in the water partially covered by ice, the “ice breaking” operation involved substantial ice floes for the ice breaking performance test. Based on the measured data, comparisons of the relationship between the ship speed and ice load, and between the locations of strain gauges and ice loads were investigated. Peak stresses higher than 20 MPa were found. The longitudinal and vertical correlations between the measurement location and ice load were analyzed, and the probability of peak stress was calculated. As a result, the probability function for higher ice loads during both operation modes was expressed in an exponential and power forms.

• 대한기계학회논문집A
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• 제28권10호
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• pp.1467-1474
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• 2004

In this study, a new damage identification method for beam-like structures with a fatigue crack is proposed. which does not require comparative measurement on an intact structure but require several measurements at different level of excitation forces on the cracked structure. The idea comes from the fact that dynamic behavior of a structure with a fatigue crack changes with the level of the excitation force. The 2$^{nd}$ spatial derivatives of frequency response functions along the longitudinal direction of a beam are used as the sensitive indicator of crack existence. Then, weighting function is employed in the averaging process in frequency domain to account for the modal participation of the differences between the dynamic behavior of a beam with a fatigue crack at the low excitation and one at the high excitation. Subsequently, a damage index is defined such that the location and level of the crack may be identified. It is shown from the analysis of vibration measurements in this study that comparison of frequency response characteristics of a beam with a single fatigue crack at different level of excitation forces enables an effective detection of the crack.

• 한국농촌건축학회논문집
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• 제14권4호
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• pp.135-142
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• 2012

This study is aimed to investigate the dimension feature of the plane about the economic type farming village Korean-style house progressed in the Chonnam province and Longitudinal feature and tries to reveal this feature through the comparing analysis with the traditional house positioned in the Chonnam province. This result is as follows. First, the main feature in plane is the setting up the column interval in front when comparing the house of Happy Village and traditional house. In case house of the Happy Village, after firstly fixed the limited scales, sizes are determined, this is due to control the set up in the post interval in this in range. Second, in the case of the traditional houses, 0.68 ratio of the building height about the side length and 0.19 ratio of the eaves extrusion about the side length are consistent ratio about dimensions. However, there is no consistent ratio or fixed law, the various dimensions show up in case of the house of Happy Village. It will be inevitable that space of the post increases for the convenience of life of the modern people. However, it has to sublate and to disregard as the identity of the morphological shown up in the Korean-style house the more various construction standards will need to be presented.