• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.4
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• pp.670-690
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• 2015

In this paper, numerical investigations for tank sloshing, based on commercial CFD package FLUENT, are performed to study effects of boundary layer grid, liquid viscosity and compressible air on sloshing pressure, wave height and rising time of impact pressure. Also, sloshing experiments for liquids of different viscosity are carried out to validate the numerical results. Through comparison of numerical and experimental results, a computational model including boundary layer grid can predict the sloshing pressure more accurately. Energy dissipation due to viscous friction leads to reduction of sloshing pressure and wave elevation. Sloshing pressure is also reduced because of cushion effect of compressible air. Due to high viscosity damping effect and compressible air effect, the rising time of impact pressure becomes longer. It is also found that liquid viscosity and compressible air influence distribution of dynamic pressure along the vertical tank wall.

• Journal of Veterinary Clinics
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• v.35 no.6
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• pp.286-289
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• 2018

A 4-year-old castrated male Maltese was referred to our hospital with heart murmur. The client did not recognize any symptoms. Auscultation revealed systolic murmur located at the left heart base. Radiographs showed right-sided cardiomegaly with the main pulmonary artery bulging and enlargement of pulmonary vessels. Echocardiogram revealed a small ventricular septal defect and a large atrial septal defect. There was also a common atrioventricular valve. Based on diagnostic imaging studies, the dog was diagnosed with transitional atrioventricular septal defect.

• Design & Manufacturing
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• v.15 no.2
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• pp.36-41
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• 2021

The 3 dimensional Pipe (Annular) Shaped Products was selected as a test sample, then a attribute of a molding shrinkage according to the parameters of a injection process was examined with PC, which is the typical engineering plastic. Both the inside and the outside diameter of the Pipe (Annular) sample were shrank into the inner direction of the part. And then the comparative analysis of the samples proved that a increasing thickness led a bigger shrinkage rate in the equal outside diametric samples, and a decreasing outside diameter caused a bigger shrinkage rate in the same thickness samples. The comparative study of the cushion volume of a injection machine showed that the molding shrinkage was most affected by the pressure strength among the resin temperature, the maintenance pressure strength and the maintenance pressure duration time. Each of the shrinkage rates according to the measuring direction and the gate position was different. As a result, the injection molded sample had not a typical circular shape.

• Journal of Trauma and Injury
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• v.19 no.2
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• pp.150-158
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• 2006

Purpose: There are two theories about the relationships between facial fractures and cranial injuries. One is that facial bones act as a protective cushion for the brain, and the other is that facial fractures are the marker for increased risk of cranial injury. They have been debated on for many years. The purpose of this study is to identify the relationship between facial fractures and cranial injuries. Methods: A retrospective study was performed on 242 patients with facial fractures. The data were analyzed based on the medical records of the patients: age, gender, cause of injury, Injury Severity Score (ISS), alcohol intake, type of facial fractures, and type of cranial injury. The patients were divided into two groups: facial fractures with cranial injury and facial fractures without cranial injury. We compared the general characteristics between the two groups and evaluated the relationship between each type of facial fracture and each type of cranial injury. Results: Among the 242 patients with facial bone fractures, 96 (39.7%) patients had a combination of facial fractures and cranial injuries. Gender predilection was demonstrated to favor males: the ratio was 3:1. The mean age was $36.51{\pm}19.63$. As to the injury mechanism, traffic accidents (in car, out of car, motorcycle) were statistically significant in the group of facial fractures with cranial injury (p=0.038, p=0.000, p=0.003). The ISS was significant, but alcohol intake was not significant. No significant relationship between facial fractures and skull fractures was found. Only maxilla fractures, zygoma fractures, and cerebral concussion had a significant difference in cranial injury (p=0.039, p=0.025). Conclusion: There is a no correlation between facial fractures and skull fractures, which suggests that the cushion effect is the predominent relationship between facial fractures and cranial injuries.

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.32-36
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• 1991

The study has been carried out to acquire some basic informations about Bacillus thuringiensis for developing the microbial pesticide. Three strains of Bacillus thuringiensis var. Kurstaki, dendrolimus and aizawai, were used in the experiments as follows. Growth characteristics of each strain were examined and parasporal protein crystals were isolated from the mixtures of spores and protein crystals by the new method of centrifugation in two-layer cushion of Renograffin using a fixed angle rotor. The results are as follows. 1. No difference was shown in growth characterestics among three strains of B. thuringiensis. In growth curves, all strains reached to exponential phase by 2 hr and stationary phase by 7-8 hr after inoculation. 2. The pH of the culture media during exponential growth stage decreased about 1.4 of a pH unit at the beginning of sporulation, but recovered during the early stage of sporulation and then remained nearly constant during the later stage. 3. As 10$m\ell$ sample was applied to two-layer cushion of Renograffin and then centrifuged for 1hr at 27,000g a fixed angle rotor, the purity and recovery ratio was 99.9% and 5.8%, respectively. It has been shown that the new method for the isolation of parasporal protein crystals was more efficient than any from the estabilished methods.

• Journal of Ecology and Environment
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• v.40 no.1
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• pp.55-65
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• 2016

Background: In this article, it was analyzed how snow melting affects the assembly of lichen and moss communities in a small area of the coastal region of Barton Peninsula, which is in maritime Antarctic. In the small area, even though there is a huge gap of difference of the environment between the snow-filled area and snow-melt one, the latter did not have distinctive environmental gradients. Results: Depending on the snow melting time, coverage and species diversity of lichens and mosses tend to increase remarkably. For species with significant changes depending on the snow-covered period, there are Andreaea regularis, crustose lichens, Placopsis contortuplicata, Usnea aurantiaco-atra, and snow algae. In this area, the process of vegetation assembly process has shown the directional development in the order of snow algae${\rightarrow}$crustose, lichen sub-formation${\rightarrow}$fruticose lichen, moss cushion sub-formation (Andreaea sociation)${\rightarrow}$fruticose lichen, and moss cushion sub-formation (Usnea sociation), according to the order of snow melting. These directional development stages are shown in gradual change in small area with the snow melting phenomena. However, in the snow-free area, where water is sufficiently supplied, it is expected that moss carpet sub-formation (Sanionia sociation) will be developed. Vegetation development in the small area with the snow melting phenomena, depending on differences of resistance on snow kill and moisture settled by species in according to the time of snow melting, tolerance model to form community is followed. Conclusions: The research results explain the development of vegetation in the Antarctic tundra and its spatial distribution according to the period for growth of lichens and mosses in the summer time by differences of snow melting in the small area. In the future, if research for the community development process in a large scale will be done, it will be helpful to figure out temporal and spatial dynamic of vegetation in the Antarctic tundra where snow and glaciers melt rapidly due to climatic warming.

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.140-147
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• 2019

The purpose of this study is to find biomechanical parameters for optimal shoes production through an ergonomic usability assessment of five existing types of shoes preferred by B-BOY. Ten experts and ten non-experts participated in the experiment, and 12 infrared cameras (Qualis, Oqus), force plate (Kistler, 9286AA) and foot pressure plate (Zebris Gmbh, Zebris PDM-System) were used to obtain the data. The results of the study are as follows. First, P shoes with a friction coefficient of 0.38 and a free moment of 0.32 N/m/kg are desirable in terms of traction capability and safety. Second, on the cushion, it was found that the N shoes 2.51 N, sec/kg and non-expert, and 2.86 N and sec/kg were suitable. Third, it is deemed appropriate for C shoes with a forefoot average pressure of 10.11 KPa (right), 10.05 KPa (left), and V shoes with a rearfoot average pressure of 8.4 KPa (right) and 8.36 KPa (left). In conclusion, the combination of the structure and material of V shoes should be developed for traction and stability, N shoes for cushion, and walking balance for C and V shoes.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.676-683
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• 2022

Minimizing patient movement during CT-guided lung biopsy is an important factor in the procedure. To minimize movement, a vacuum cushion was used to evaluate its effectiveness. The subjects of this study were 116 patients aged 40 years or older who had good coordination with postural fixation and breathing control. Posture measurements were performed in the supine position, prone position, oblique position, and lateral position according to each position of the lung lesion biopsy lesion. Measurement positions were measured in the anterior, posterior, right, and left positions based on the anatomical posture. In the prone position, the mean difference between the non-use and the use of the posterior was 1.7905, and t=2.913 (p<0.01), and the mean difference between the non-use/use was statistically significant. The difference between the unused and used averages of left was 2.4105, and the difference between the left averages was also significant with t=3.684 (p<0.01). The difference between the unused and used averages of the right was 2.3263, with t=3.791 (p<0.01). The mean difference between unused and used is statistically significant. As a result of statistical analysis, the biopsy of the lung lesion using a fixation device showed less movement in all postures. It is considered that it is meaningful in that it is possible to conduct a more accurate biopsy procedure and minimize the patient's posture movement by using a fixation device during the CT-guided biopsy of the lung lesion.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.489-492
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• 2005

Even though the blood pressure is one of the most widely used index for the healthcare monitoring of hypertensive and normotensive persons, there is no non-intrusive measurement method which is commercialized until now. Pulse Arrival Time (PAT) is known that it has close relation with the systolic blood pressure (SBP) and arterial stiffness. In this study, SBP estimation methods by non-intrusive measurement of PAT are suggested. For the unconstrained measurement of PAT, the first method used the electrically non contact electrocardiogram (ENC-ECG) technique and the reflective type of Photoplethysmography (PPG) sensor on the computer mouse. In the second method, ENC-ECG and the air pressure sensor in the seat cushion on a chair were measured. The third method used ECG electrodes and PPG sensors on the toilet seat cover. The validation and regression analysis of the relationship of PAT and SBP are summarized. These methods have considerable errors to be used for all people. But these can be applied for each subject after the parameter customization within acceptable error. So, it is feasible for suggested methods to be used for monitoring of SBP in daily life in non-intrusive way when there is personal identification system of each subject.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.419-431
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• 2017

The forest slopes cause substantial local changes in soil properties and an increase in soil erosion after extreme rainstorms. The high soil erosion rates on forest slopes need the effective use of growing media to control the soil runoff. Therefore, we prepared six different lignocellulosic growing media such as peat, perlite, and wood meal as the base materials and carboxymethyl cellulose (CMC), glucomannan, starch, old corrugated containerboard, and computer printout as the additional materials for the prevention of simulated rainfall-induced runoff. The growing media containing old corrugated containerboard efficiently reduced the percentage of soil runoff; however, it could not completely cushion the influence of crust. The best results for plant growth, except in the leaf area, were also obtained with the growing media containing old corrugated containerboard, suggesting an interesting way of paper recycling and an economic benefit for plant or crop growth in forest slope.