• Journal of Industrial Technology
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• v.21 no.B
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• pp.273-280
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• 2001

In this study, a driver model based on the lead-lag controller for stable maneuver of a highly nonlinear, multi-dimensional, numerically stiff multibody vehicle model according to the various handling test requirements such as steady-state cornering, double lange change, etc. is presented The lead-lag controller is developed with lead and lag compensation. which use the transfer function with cross-over frequency by frequency response method. The proposed driver model is applied to a vehicle model in steady-state and slalom maneuver to verify its effectiveness and validity. The results show that the proposed path control strategy is excellent both in pursuing the desired course and stability of the vehicle.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.723-734
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• 2008

The main reason for deinterlacing is frame-rate conversion. The other reason for deinterlacing is of course improve clarity and reduce flicker. Using a deinterlacer can help clarity and stability of the image. Many deinterlacing algorithms are available in image processing literatures such as ELA and E-ELA. This paper propose a new statistical deinterlacing algorithm based on statistical tests such as the Bartlett test, the Levene test and the Kruskal-Wallis test. The results obtained from the proposed algorithms are found to be comparable to those from many well-known deinterlacers. However, the results in the proposed deinterlacers are found to be more efficient than other deinterlacers.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.322-329
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• 2016

This study is about the method to control the quality of material used to repair leakage and crack of concrete structure and suggests the "Temperature Stability Test Method" as a follow-up study. In the result of performance evaluation for 45 samples of 15 types in 5 series, the temperature stability test showed different material changes including rolling down, volume change, and color change as they are frozen and melt repeatedly in the somewhat extreme conditions at low($-20^{\circ}C$) and high($60^{\circ}C$) temperatures, where 13 samples (approx. 29%) and 32 samples (approx. 71%) showed leakage, respectively, in the permeability test to evaluate leakage. This result shows the enough importance of setting the quality control criteria of leakage repair material currently used to maintain concrete structures considering the temperature conditions, and proves the applicability of the Temperature Stability Test Method as a standard test method to ensure long-term durability of concrete structure.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.569-575
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• 1988

Storage stabilities of ramyons fried in palm oil and beef tallow with added antioxidants and their synergists were investigated by comparing the changes in physicochemical parameters and n-hexanal concentrations of oils extracted from ramyons during storage. Ramyons fried in palm oil and beef tallow with added ${\delta}-tocopherol$ $({\delta}-toc)$ showed an enhanced storage stabilities when compared to those fried in the oils with ${\alpha}-tocopherol$ $({\alpha}-toc)$. Ascorbyl palmitate was found to be a better synergist than citric acid for the antioxidant activity of both ${\delta}-toc\;and\;{\alpha}-toc$. Phenolic antioxidants gave a better storage stability than tocopherol when ramyon was fried in beef tallow, while a mixture of BHA and BHT gave an inferior storage stability than${\alpha}-toc$ when ramyon was fried in palm oil. The effectiveness of the antioxidants tested on storage stability of stored ramyon had a close relationship to the n-hexanal concentration. On the other hand, the paramenters such as peroxide value, carbonly value, and conjugated diene concentration showed inconsistency during the course of the storage experiment.

• Geomechanics and Engineering
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• v.36 no.1
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• pp.39-50
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• 2024

Bitumen and high-quality subangular aggregates, the two principal materials used for asphalt concrete construction, are finite and expensive materials. The general availability of crumb rubber and naturally occurring aggregates of different shapes, especially flat and elongated shapes, indicates that they are feasible alternative materials for expanding the volume of bitumen and utilizing a wider range of aggregate shapes for the development of asphalt concrete, with an associated environmental benefit. The study investigated the effect of adding up to 15% crumb rubber and aggregates sorted into different groups, i.e., rounded, elongated, flat, and their combinations, on the rheological and mechanical properties and durability of 50/70 of hot-mix asphalt pavement. The addition of crumb rubber decreased ductility and penetration but increased the softening point. For a 5.5% bitumen content, asphalt concrete briquettes consisting of 7% crumb rubber and three types of aggregate shapes, i.e., 100% rounded, a mix of 75% rounded and 25% elongated, and a mix of 75% rounded, 15% elongated and 10% flat, were associated with high Marshall stability and indirect tensile strength as well as low lateral deformation due to their high solidity and moderate angularity ratio. Also, the addition of 7% crumb rubber resulted in a significant improvement in the tensile strength ratio and rebound strain of briquettes consisting of 75% rounded and 25% elongated aggregates and those with 75% rounded, 15% elongated and 10% flat aggregates. In relation to the parameters investigated, the three groups of briquettes met some of the local (South Africa) requirements for the surface course and base course of low traffic volume roads.

• Clinical and Experimental Pediatrics
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• v.53 no.5
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• pp.634-638
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• 2010

Purpose: In Kyung Hee East-West Neo Medical Center, Seoul, Korea, efforts to raise rooming-in care success rate have been undertaken since when the hospital was established in 2006. We intended to analyze our experience over the past 3 years of period and to discuss the advantages of rooming-in. Methods: We analyzed the rooming-in practice rate, failure rate, and the breast feeding rate. Subjects were 860 normal healthy neonates from June 2006 to June 2009. Results: Among these 860 cases, 83 babies were required separation out of rooming-in in the middle of the course. Among these 83 cases, 70 cases had to stop the course due to poor condition of babies and 13 cases due to maternal condition. 70 cases of infant's causes consist of 68 cases of NICU admission and 2 cases of poor feeding support. The other 13 cases of separation include refusal by maternal condition. Therefore the success rate of rooming-in for the last 3 years was 90.3%, that is 777 cases among the total 860 cases. The percentage of exclusive breast feeding was 64%, that of mixed feeding with breast and formula feeding was 25%, and formula feeding only was 11%. Conclusion: We experienced successful rooming-in care for the last 3 years. Nursery facilities should educate and encourage the advantages of rooming-in, including the good formation of attachment between mother and infant, emotional stability, protection from infection, and increased breast feeding rate so that rooming-in care can be fully established.

• Hip & pelvis
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• v.35 no.2
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• pp.133-141
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• 2023

Purpose: Isolated acetabular fractures can occur as a result of a high energy impact on the hip joint. Surgery is required for most patients with an isolated acetabular fracture in order to alleviate pain, restore joint stability, and regain hip function. This study was conducted in order to examine the course of hip function in patients after surgical treatment of an isolated traumatic acetabular fracture. Materials and Methods: This prospective series of consecutive cases included patients who underwent surgery for treatment of an isolated acetabular fracture in a European level one trauma center between 2016 and 2020. Patients with relevant concomitant injuries were excluded. Scoring of hip function was performed by a trauma surgeon using the Modified Merle d'Aubigné and Postel score at six-week, 12-week, six-month, and one-year follow-up. Scores between 3-11 indicate poor, 12-14 fair, 15-17 good, and 18 excellent hip function. Results: Data on 46 patients were included. The mean score for hip function was 10 (95% confidence interval [CI] 7.09-12.91) at six-week follow-up (23 patients), 13.75 (95% CI 10.74-16.76) at 12-week follow-up (28 patients), 16 (95% CI 13.40-18.60) at six-month follow-up (25 patients), and 15.50 (95% CI 10.55-20.45) at one-year follow-up (17 patients). After one-year follow-up, the scores reflected an excellent outcome in 11 patients, good in five patients, and poor in one patient. Conclusion: This study reports on the course of hip function in patients who have undergone surgical treatment for isolated acetabular fractures. Restoration of excellent hip function takes six months.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.8-12
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• 1985

In the pure Phragmites communis grassland in the lower course of Nakdong river, the seasonal changes of standing crop and productive structure, annual changes of the maximum standing crop, and annual net production were estimated. The maximum standing crop of the pure P. communis grassland is on mid-September, the maximum average daily productivity was $32.7g/m^2/day$ from June to July. The leaf area index of the pure reed grassland increased to July, and then decreased slowly. The logitudinal growth of above-ground parts of the reed grassland was maximum state, 320cm, on mid September. Annual net production was $3,399g/m^2/year$, and it suggests that grassland is stable. Productive structure of the pure reed grassland indicated that the distribution of leaf was concentrated on the upper parts according to the grassland maturation.

• Journal of Navigation and Port Research
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• v.41 no.1
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• pp.1-8
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• 2017

The estimation of non-linear ship motion is one of the most important issues in recent studies of ship stability. In this paper, bispectral analysis and bicoherence analysis were introduced in order to analyze the non-linear ship motion. In addition to the previously observed non-linear pitching motion in following seas, this study observed the non-linear phase coupling of pitching motion in following & quartering seas, and starboard beam seas. By comparing phase coupling between each frequency quantitatively via the bicoherence analysis, it was confirmed that non-linear phase coupling was much stronger in frequency regions other than the peak frequencies of a power spectrum. Furthermore, it was found out that the results of bicoherence calculation were analagous to each other, although the different normalization methods were applied.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.385-392
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• 2017

This research presents the results of a study on the trajectory characteristics of barges with different configurations. A towing experiment was carried out in a water tank with three types of barges in two cases: with and without skegs. The effects of towline length on trajectory were also observed. This study analyzed and compared the length and amplitude of trajectory shapes for each barge in various combinations. It revealed that the trajectory of a barge is influenced not only by skegs but also by the length of the towline. As a result of this work, it can be clearly seen that skegs significantly improve the course stability of a towed barge regardless of differences in bow shape or towline length. Water tank test results also indicated that the length of a towline plays a key role in affecting the trajectory characteristics of a barge-towing system. The length and amplitude of the slewing motion of a barge increased with an increase in the length of the towline connected to the barge. Validation of the present research results should be carried out by further experiments and computational comparisons in the near future.