• Journal of the Korean Society of Visualization
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• v.21 no.1
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• pp.94-102
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• 2023

Three design parameters were considered in this study: outlet nozzle angle (30°, 60°, 80°), neck length (1 mm, 3 mm), and flow rate (0.5, 0.6, 0.7, 0.8 lpm). A neck diameter of 0.5 mm induced cavitation flow at a venture nozzle. A secondary transparent chamber was connected after ejection to increase bubble duration and shape visibility. The bubble size was estimated using a Gaussian kernel function to identify bubbles in the acquired images. Data on bubble size were used to obtain Sauter's mean diameter and probability density function to obtain specific bubble state conditions. The degree of bubble generation according to the bubble size was compared for each design variable. The bubble diameter increased as the flow rate increased. The frequency of bubble generation was highest around 20 ㎛. With the same neck length, the smaller the CV number, the larger the average bubble diameter. It is possible to increase the generation frequency of smaller bubbles by the cavitation method by changing the magnification angle and length of the neck. However, if the flow rate is too large, the average bubble diameter tends to increase, so an appropriate flow rate should be selected.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.706-713
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• 2004

This paper introduced an alternative method called USCP (Unpenetrated Sand Compaction Pile). In USCP, the toe of the sand pile does not reach to the lower supporting layer. Hence it is possible to reduce the amount of sand required. However, the degree of improvement could not be the same as SCP. Effective soil improvement, nevertheless, might be possible by combining both methods. In this paper, an improved method that cross over both SCP and USCP was discussed. And in order to verify applicability to a clay layer, consolidation behaviors with different conditions were analyzed and compared using FEM(Finite Element Method) based on the elasto-viscosity theory. From the results, it is concluded for the characteristic of settlement of USCP that the lower degree of replacement and the smaller ratio of penetration($H_d/H$), the larger is the settlement of the lower part of the clay layer comparing to the layer with no improvement. It is also concluded that the ratios of allotment of stress (m) calculated from the final settlements with 30% of degree of replacement are $1.8{\sim}3.3$ for $H_d/H=lOO%,\;1.8{\sim}4.0\;for\;H_d/H=75%,\;and\;1.8{\sim}3.8\;for\;H_d/H=50%$. Besides, the ratio of allotment of stress decreased as the degree of replacement decreased.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.174-180
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• 1995

The damage rate according to the age of black pine trees in the Black pine bast scale, Matsucoccus thunbergianae was high from 7 to 22 year old trees. According to damaged degree of damaged trees, it showed great difference in infection rate of saprophitic fungi. The period until the developmental degree of saprophitic fungi became maximized degree of 7 was required about 48 days in dead tree of 100 percent, about 54 days in one of above than 80 percent, about 75 days in one of 40~50 percent, but the dead tree less than 10 percent and health tree was retained the 3~4 developmental degree of saprophitic fungi, after 80 days. The ring width of damaged trees showed as follows. The non damaged trees was 3.52 cm, 0.77 cm in the damaged trees of 100 percent, 0.88 cm in the ones of 80 percent, 1.22 cm in the ones of 40~50 percent and 1.37 cm in the ones of les than 10 percent, respectively. Number of cells per unit area was smaller in the case of greater damaged trees, gradually. Also moisture content was very high in greater damaged trees, and bending strength was lower. Extracts by the one percent NaOH showed a small amount.

• Journal of Korean Neurosurgical Society
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• v.44 no.3
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• pp.136-140
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• 2008

Objective : Numerous studies have compared the characteristics of familial intracranial aneurysms with those of non-familial aneurysms. To better understand familial subarachnoid hemorrhage (SAH), we studied a series of patients with SAH who had at least one first-degree relative with SAH, and compared our results with those of previous studies. Methods : We identified patients treated for SAH at our hospital between January 1993 and October 2006 and analyzed those patients with one or more first-degree relatives with SAH. We retrospectively collected data from patients with a family history and searched for patients who had relatives with aneurysms or who had been treated at other hospitals for SAH. Results : We identified 12 patients from six families with at least two first-degree relatives with SAH. All patients had affected first-degree relatives; in five families, they were siblings. The mean age at the time of rupture was 49.75 years; in four families, the age difference was within 5 years. In five patients (42%), the aneurysm was located in the middle cerebral artery. Only one patient had an aneurysm in the anterior communicating artery. Conclusion : In agreement with previous studies, our results showed that familial aneurysms, in comparison with non-familiar aneurysms, ruptured at a younger age and smaller size, had a high incidence in the middle cerebral artery, and were underrepresented in the anterior communicating artery. Interestingly, the age at the time of rupture was similar between relatives. Screening should be considered in the fifth or sixth decade for those who have a sibling with SAH.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.17-24
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• 2015

In this study, the effect of delignification degree of Korean white pine wood on fibrillation efficiency by wet disk-milling (WDM) and the properties of thus-obtained microfibrillated cellulose (MFC) were investigated. The effect on the tensile properties of nanopaper was also investigated. The delignification degree was adjusted by repeating 'Wise' method using sodium chlorite and acetic acid. The increase in delignification degree improved fibrillation efficiency, showing the smaller nanofiber dimension at the shorter WDM time. The filtration time of MFC water suspension was increased by the increase of WDM cycles. Tensile strength and elastic modulus of the nanopaper were increased by increasing delignification degree and disk-milling cycles.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1726-1734
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• 1993

This paper propose a survivable communication network design process using node degree that augments the usual traffic flow and cost analyses with previously ignored topological survivability and computing time considerations. At first, decide a initial topology, and then measure a throughput of network. If the throughput is smaller than the required traffic, add edge to the optimum place by using minimum node degree and link distance. Otherwise, drop useless edge by using maximum node degree, link distance and link utilization. This process is repeated until throughput equals to the required traffics. This Process designs a survivable communication network with the minimized cost and computing time and usual traffic flow. The design proceses that minimized computing time are freely select initial topology and easily design a large network. And these results of algorithm are compared with the Kris and Pramod's in order to analyses the perfmance of the designed network.

• The Research Journal of the Costume Culture
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• v.19 no.6
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• pp.1205-1220
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• 2011

The purpose of this study is to verify the change of body posture by putting on the late $19^{th}$ century English women's bodice or waistcoat. This study analyzed the female somatotype which puts on upper garments of Victorian era with using 3D body scan technology. Two sets of $19^{th}$ century women's bodice and waistcoat patterns were developed with the $19^{th}$ century model size and those patterns were used for making the experimental garments. The fit of experimental garments was evaluated by the degree of change with posture and waist measurements. Three women with the same waist girth measurements with the model size were participated to the fitting test. The postural change was measured from cross-sectional body diagrams. The result of this study showed that the waist measurement of the late $19^{th}$ century English women's bodice and waistcoat pattern was smaller than the waist girth measurement. These garments compressed the midriff of the body and it made women's distinct body silhouette. The waist girth measurement of 1876 bodice pattern was 9.2cm smaller than presented model size. The subjects' waist girth measurements were shortened by 5.0~6.1cm after wearing the 1876 bodice garment. The waist girth measurement of 1880 waistcoat pattern was 7.1cm smaller than presented model size. The subjects' waist girth measurements were shortened by 2.7~3.7cm after wearing the 1880 waistcoat garment. The back side parts of their waist were compressed and their postures were changed. The neck and shoulders were moved forward after wearing the experimental garments. These results showed that body posture could be changed to "S" shape silhouette as wearing the late $19^{th}$ century English women's bodice or waistcoat.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.321-328
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• 1999

Pulmonary blood vessels with diameters of $200{\sim}400\;{\mu}m$ produce considerably more force in response to vasoconstrictor drugs than those which are either smaller or larger. We have therefore investigated whether or not hypoxic pulmonary vasoconstriction (HPV) is more powerful in vessels of these diameters. We have also looked at the possibility that vessels from different regions of the lung respond differently. To do this we have grouped vessels according to their location within the lung as well as by size. We used a small vessel myograph (Cambustion AM10, Cambridge, UK) to study 208 preconstricted $(1\;{\mu}M\;PGF_{2{\alpha}})$ small pulmonary arteries $(300{\sim}800\;{\mu}m$ diameter when stretched to a tension equivalent to 25 mmHg transmural pressure) from 39 rats anaesthetized with 2% inspired halothane. A biphasic contraction was observed in response to hypoxia (ca. 25 mmHg $Po_2).$ The magnitudes of both the first, transient, phase (PT, peak tension) and of the second, sustained, phase (SST, steady state tension) were measured. The latter was measured 40 min after the start of hypoxia. The first phase was most pronounced in vessels with an average diameter of 423 ${\mu}m$ while the second phase was most pronounced in larger vessels (mean diameter 505 ${\mu}m).$ These maximal responses were all seen in vessels somewhat larger than reported by others. The responses of smaller vessels $(400{\sim}500\;{\mu}m)$ did not depend upon their location within the lung, but those of larger vessels $(600{\sim}700\;{\mu}m)$ showed regional differences. Those from the right lobe and those from the base of the lung gave the largest responses. It was especially noticeable that large vessels (631 ${\mu}m$ diameter) from the base of the right lung gave the biggest responses. Thus HPV seems to occur not in a uniform manner, dependent solely to the size of vessels, but it also depends to some degree on the region of the lung from which vessels have been taken. Furthermore, our results suggest that larger vessels, as well as smaller ones, may contribute significantly to HPV.

• Journal of the Korea Fashion and Costume Design Association
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• v.1 no.1
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• pp.127-139
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• 1999

The purpose of this study was to understand the preference of fashion materials according to the degree of consciousness and satisfaction of body. A survey was conducted using the randomly selected 439 woman students in the twenties. The consciousness variable had three levels which were lean, medium, and obese shape for each whole, upper and lower body with self-consciousness. Also, satisfaction variable had three levels which were satisfying, average, and unsatisfying group. We analyzed the data using analysis of correlation, crosstabulation analysis, and analysis of variance including Duncan multiple test. The results were as follows: 1) There was the positive correlation between height, leg, and arm length, and each variable, and the negative correlation between back, hip, thigh, waist, lower leg, ankle, and upper arm, and each variable. Also, we could observe the pattern that the larger the head or the more the weight was, the lower the satisfaction of body was. 2) There were no strong correlation between breast and hand size and each variable. From the crossed classification, we could observe the trend that the smaller the breast was, the lower the satisfaction of body was. 3) There were the strong correlation between whole and upper body in consciousness degree and between whole and lower body in satisfaction. 4) The consciousness of the whole body was shown lean shape 23.4%. medium shape 49.2%, and obese shape 27.2%. For the satisfaction degree of the whole body, satisfaction was shown 6.8%, average 41.7% and unsatisfaction 51.4%, so the satisfaction group is very small. 5) From the analysis for the consciousness degree of the whole body, the preferred fashion materials were polyester and acetate in casual wear, linen, polyester, acryl, T/W, and polyurethan in formal wear, and cotton, nylon, TIC, and T/W in sports wear. There was significant difference in casual wear, formal wear, and sports wear, but, not in underwear and accessories among he consciousness groups. 6) From the analysis for the satisfaction degree of the whole body, the preferred fashion materials were linen, silk, and acetate in casual wear, cotton in underwear, polyurethane in formal wear, and nylon in sports wear. There was the significant difference in casual wear, underwear, formal wear and sports wear, but, not in accessories among the satisfaction groups.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.1
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• pp.104-126
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• 1999

The purpose of this study was to compare and evaluate the stress distribution and displacement developed in the abutment teeth and residual ridge area by madibular unilateral distal extension removable partial denture with 2 different retainer designs. The retainers on right and left canine and right 2nd molar were Alters clasp in one model and telescopic crown in the other model. The stress distribution of abutment teeth and residual ridge area on two model were compared and analyzed with 3-dimensional finite element method. 150N and 400N forces were applied vertically, 30 degree and horizontally on the central fossa area of left 1st molar of the removable partial denture, and then stress distribution patterns were analyzed and compared. The results were as follows 1. As the magnitude and angulation of applied force were increased, the magnitude of stress on the right and central residual ridge area and the right canine of the telescopic type increased and comparing to those of the Alters clasp type. 2. As the magnitude and angulation of applied force were increased, the mesial direction of displacement on the right residual ridge area and the right tooth of the telescopic type increased and the distal direction of displacement on left residual ridge area and the left canine increased comparing to those of Akers clasp type. 3. As the vertical force was applied, the distal direction of the displacement of the right tooth were greater and that of the left canine was smaller and the upward displacement of the right canine was greater in telescopic partial denture than those of Akers clasp type. 4. As the 30 degree force was applied, the mesial direction of the displacement of the right tooth were greater and the distal direction of the displacement of the left canine was smaller and the upward displacement of the right canine was greater in telescopic partial denture than those of Akers clasp type. In the horizontal force the results were same in right area tooth but the distal direction of displacement was greater in left canine. 5. In both removable partial dentures, as the magnitude and degree of force were increased, the stress and displacement were increased. The compressive force was dominative than the ten sile force. 6. In both removable partial dentures, the magnitude of stress was greater on mucosal tissue area than that of the alveolar bone area on distal extension residual ridge area but the result was reversed on anterior residual ridge area. The displacement was always greater on mucosal tissue area than that of alveolar bone area.