• Journal of Chest Surgery
• /
• v.15 no.3
• /
• pp.274-277
• /
• 1982

A Clinical analysis of 59 patients of thoracic empyema was done who were received surgical intervention at dept. of thoracic surgery of the C.A.F.G.H. in the period of 2.5 years from January 1979 to June 1982. Occurrence ratio of Left and Right side pleural cavity of empyema was 1: 1.4. The predisposing factors of empyema were pulmonary Tbc. [49%], Chest pain [25%], Cough [8%], in order. B.P.F. was associated with empyema in 5 cases. The pleural cavity empyema was treated with several surgical procedures and conservative measures. Among of the 59 cases, the 30 cases [50%] were treated with decortication, 12 cases [20%] with closed thoractomy drainage, 9 cases with frequent thoracenteses, 5 cases with partial decortication and thoracoplasty and 3 cases with open thoracostomy tube drainage. Among of the 59 cases thoracic empyema, the full recovery were in 32 cases [54%], partial recovery in 20 cases [34%], not improved in 3 cases [5%] and 3 cases were died. The mortality rate was 5% and the recovery rate was 89%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.14 no.7
• /
• pp.578-583
• /
• 2001

The bushing for high voltage and large and power should endure weight of itself and force of pushing from contact with circuit breaker. Like this, epoxy mold bushing has to be strong without fault. However, the external circumstances and internal factors was caused by partial discharge, flashover and dielectric breakdown. Therefore, to remove external factor of defect and to prevent the internal cracks and cavity generated from the contraction on interface of Cu-Epoxy, we should form semi-conductive layer on Cu bar by carbon. Then, the PD properties and the insulation qualities of epoxy mold type bushing was able to improved by roles of cushions for the direction of diameter and by effects fo natural sliding like as separated from conductor for the direction of length. So, in this work, we could prove the method of semi-conductive layer in making the long conductor.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.25 no.4
• /
• pp.209-213
• /
• 1989

The author suggested control method of partial cavitation with electro-magnetic accelerator and showed that the cavity shape decreased with this suggestion which compared with the theoretical ones. Using the cavity flow method proposed by the author in this paper, it is predicted that cavitation volume of the shape is less than the previous type one. Comparisons were performed in order to verify these facts, using both shape which calculated by the method. It was found that the difference of cavitation performance between the two shape of volume were decreased, because of the new method accelerated of flow more than previous theoretical ones.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.5 no.1
• /
• pp.44-58
• /
• 1994

The formants of the 9 Korean standard vowels(which used by the average people of Seoul, central-area of the Korean peninsula) were measured by analysis with the linear predictive coding(LPC) and fast Fourier transform(FFT). The author already had reported the constriction area for the Korean standard vowels, and with the existing data, the distance from glottis to the constriction area in the vocal tract of each vowel was newly measured with videovelopharyngograms and lateral Rontgenograms of the vocal tract. We correlated the formant frequencies with the distance from glottis to the constriction area of the vocal tract. Also we tried to correlate the formant frequencies with the position of tongue in the vocal tract which is divided into 2 categories : The position of tongue in oral cavity by the distance from imaginary palatal line to the highest point of tongue and the position in pharyngeal cavity by the distance from back of tongue to posterior pharyngeal wall. This study was performed with 10 adults(male : 5, female : 5) who spoke primary 9 Korean standard vowels. We had already reported that the Korean vowel [i], [e], $[{\varepsilon}]$ were articulated at hard palate level, [$\dot{+}$], [u] were at soft palate level, [$\wedge$] was at upper pharynx level and the [$\wedge$], [$\partial$], [a] in a previous article. Also we had noted that the significance of pharyngeal cavity in vowel articulation. From this study we have concluded that ; 1) The F$_1$ is related with the oral cavity articulated vowel [i, e, $\varepsilon$, $\dot{+}$, u]. 2) Within the oral cavity articulated vowel [i, e, $\varepsilon$, $\dot{+}$, u] and the upper pharynx articulated vowel [o], the F$_2$ is elevated when the diatance from glottis to the constriction area is longer. But within the lower pharynx articulated vowel [$\partial$, $\wedge$, a], the F$_2$ is elevated when the distance from glottis to the constriction area is shorter. 3) With the stronger tendency of back-vowel, the higher the elevation of the F$_1$ and F$_2$ frequencies. 4) The F$_3$ and F$_4$ showed no correaltion with the constriction area nor the position of tongue in the vocal tract 5) The parameter F$_2$- F$_1$, which is the difference between F$_2$ frequency and F$_1$ frequency showed an excellent indicator of differenciating the oral cavity articulated vowels from pharyngeal cavity articulated vowels. If the F$_2$-F$_1$ is less than about 600Hz which indicates the vowel is articulated in the pharyngeal cavity, and more than about 600Hz, which indicates that the vowel is articulated in the oral cavity.

• Journal of Advanced Marine Engineering and Technology
• /
• v.12 no.1
• /
• pp.53-61
• /
• 1988

Most of the recent for the flow field hydrofoil in partially cavitating condition are the ones which are linearized, and the problem of cavity end region for hydrofoil is not verified. This paper deals with a study on characteristics of end region flow field for partially cavitating hydrofoil by using a characteristics of shear turbulence flow and nonlinear cavity flow theory. The results obtained as follows : 1) Shear layer thickness is decreased gradually going to the end section of hydrofoil. When attack angle is large, it is appeared largely at the region of partial cavitation after its collapsing. 2) The fluctuation velocity of a second-degree relative direction have minimum value at the front of hydrofoil or at the end of hydrofoil. The difference for the validity of attack angle is appeared largely at the surrounding of .chi.$_{e}$ point. 3) The fluctuation velocity of transverse direction decrease from the maximum thickness of cavitation to the end of hydrofoil, but it undergoes largely the effect of pressure recovery. The difference is larger at the region of partial cavitation after its collapsing than at the of hydrofoil. 4) The distribution of Reynolds stress have maximum values at the region of partial cavitation after its collapsing and the end of foil, and the larger attack angle, the larger the distribution of value.e.

• Journal of Mechanical Science and Technology
• /
• v.20 no.10
• /
• pp.1773-1778
• /
• 2006

Steady-state natural convection heat transfer characteristics from cylinders in a multiply-connected bounded region are clarified. A spectral finite difference scheme (spectral decomposition of the system of partial differential equations, semi-implicit time integration) is applied in numerical analysis, with a boundary-fitted conformal coordinate system through a Jacobian elliptic function with a successive transformation to formulate a system of governing equations in terms of a stream function, vorticity and temperature. Multiplicity of the domain is expressed explicitly.

• The Journal of the Acoustical Society of Korea
• /
• v.33 no.6
• /
• pp.358-365
• /
• 2014

When a ship propeller having wing type sections rotates at high speed underwater, local pressure on the blade decreases and various types of the cavitation inevitably occur where the local pressure falls below the vapor pressure. Fundamentally characteristics of the cavitation are determined by the shapes of the blade section and their operating conditions. Underwater noise radiated from a ship propeller is directly connected to the occurrence of the cavitation. In order to design low noise propeller, it is preferentially demanded to figure out key features: how the cavity is generated, developed and collapsed and how the effect of viscosity works in the process. In this study, we first perform inviscid analysis of the partial cavity generated on two dimensional hydrofoil. Secondly, viscous analysis using FLUENT with different turbulence and cavitation models are presented. Results from both approaches are also compared and estimated.

• Journal of Ocean Engineering and Technology
• /
• v.31 no.1
• /
• pp.8-13
• /
• 2017

Cavitation is used in various fields. This study examined the drag reduction of an underwater vehicle using cavitation. In this study, the natural partial cavitation analysis results were verified using CFD code with the Navier-Stokes equation based on a mixture model. The momentum and continuity equations in the mixture phase were separately solved in the liquid and vapor phases. The solver employs an implicit preconditioning algorithm in curvilinear coordinates. The results of a computational analysis showed good agreement with the experiment. A computational analysis was also performed on the supercavity. The study investigated the cavity characteristics and drag of an underwater vehicle and studied the speed required to achieve a supercavity. Finally, a 1DOF analysis was carried out to investigate the thrust system for a supercavity. As a result, one of the methods for determining a suitable thrust system for a supercavitating underwater vehicle was presented.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.18 no.2
• /
• pp.144-153
• /
• 2009

It is widely known that no-slip assumptions are often violated on regular basis in micrometer- or nanometer-scale fluid flow. In the case of cavity-filling process of nanoimprint lithography(NIL), slip phenomena take place naturally at the solid-to-liquid boundaries, that is, at the mold-to-polymer or polymer-to-substrate boundaries. If the slip or partial slip phenomena are promoted at the boundaries, the processing time of NIL, especially of thermal-NIL which consumes more tact time than that of UV-NIL, can be significantly improved. In this paper it is aimed to elucidate how the cavity-filling process of NIL can be influenced by the slip phenomena at boundaries and to what degree those phenomena increase the process rate. To do so, computational fluid dynamics(CFD) analysis of cavity filling process has been carried out. Also, the effect of mold pattern shape and initial thickness of polymer resist were considered in the analysis, as well.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
• /
• v.61 no.11
• /
• pp.605-610
• /
• 2018

Background and Objectives The purpose of the present study was to evaluate the usefulness of a posterior-based buccinator myomucosal flap (the Bozola flap) for the reconstruction of oral cavity defects after tongue cancer resection. Subjects and Method Fifteen patients who underwent from 2014 to 2016 reconstruction of the oral cavity with a Bozola flap after surgical management of tongue cancer were enrolled in the study. Patient characteristics, surgical outcomes, and complications associated with the Bozola flap were evaluated. Results The flap was successfully harvested and transferred in all patients. The mean flap harvesting time was 25.3 min. The donor site was closed primarily in 14 patients, and a buccal fat pad flap was used in one patient. Although partial necrosis of the flap occurred in two patients, no other major complications were noted. Conclusion The results of this study demonstrate that the Bozola flap is a good option for reconstruction of moderate sized oral cavity defects in tongue cancer patients.