• Journal of Chest Surgery
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• v.29 no.10
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• pp.1118-1122
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• 1996

From January 1990 through December 1995, 43 patients underwent diaphragmatic plication for the management of phrenic nerve palsy .complicating various pediatric cardiovascular surgery. Their mean age at plication was 11.1 months and sex ratio was 31 males to 12 females. In order of decreasing incidence, the primary cardiovascular procedures included modified Blalock-Taussig shunt (7), total correction for the Tetralogy of Falloff (7), arterial switch operation (6), unifocalization for the pulmonary atresia with VSD (3), modified Fontan operation (3), VSD patch closure (3) and others. The involved sides of diaphragm were right in 17, left in 2) and bilateral in 3. Extensive pericardial resection with electocauterization of resected margin was thought to be the most common cause of phrenic nerve palsy (20). The interval between primary operation and plication ranged from the day of operation to 98 days (median 11 days). The methods of plication were central pleating technique(plication with phrenic nerve branch preservation) in 41, and other technique In 2. 10 patients died after plication (7: early, 3; late), and the causes of death were thought to be unrelated to plication itself. Among the 36 early survivors, extubation or cessation of positive pressure ventilation could be accomplished between 1 and 24 days postoperatively(mean : 4.5). Cumulative follow-up was 92 patient years without major complications. Postoperative follow-up fluoroscopy was performed in 6 patients, and the location and movement of plicated diaphragms were satisfactory in 5 patients. We concluded that diaphragmatic plication with preservation of phrenic n rve branch could lead to cessation of positive pressure ventilation and complete recovery of diaphragmatic function in the long term, unless the phrenic nerve was irreversibly damaged.

• Journal of Chest Surgery
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• v.32 no.6
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• pp.561-566
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• 1999

Background: It is not easy to surgically correct caustic pharyngeal strictures and a lot of effort is required to restore normal swallowing after the surgery. The authors reviewed the course in patients who underwent pharyngocolostomy. Material and Method: From August 1995 to March 1998, 6 patients with caustic stricture underwent esophageal reconstruction surgery. The time of injury to the replacement of the esophagus was from 3 months to 2 years and 4 months. The left colon was used in all patients. The surgical route was used under the sternum in 5 patients and through the esophageal hiatus in 1 patient. In the cervical anastomoses, the cervical pharyngocolic anastomosis was performed on the left pyriform sinus after a partial resection of the thyroid cartilage in 3 patients and on the posterolateral aspect of the inferior pharyngeal constrictor in 3 patients. Result: Postoperative complications consisted of a dysphagia in 3 patients and left vocal cord palsy in 1 patient. There was no cervical anastomotic stricture. Revisional procedures consisted of an esophageal dilation and free jejunal graft in 1 patient, supraglottic scar band resection in 1 patient, and colonic mucosal resection in 1 patient. Swallowing training was required in the 3 patients with dysphagia. Restoration of normal swallowing was obtained in all patients between the 9th and the 303rd day. Conclusion: Pharyngocolostomy is a satisfactory method of treatment for patients with intractable caustic stricture. Pharyngocolojejunostomy is an effective alternative for esophagocologastrostomy in cases where gastric outlets are involved.

• Radiation Oncology Journal
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• v.5 no.1
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• pp.49-58
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• 1987

Hypertermia for the treatment of cancer has been introduced for a long time and the biological effect for the use of hyperthermia to treat malignant tumors has been well established and encouraging clinical results have been obserbed. Unfortunately, however, the engineering or technical aspects of hyperthermia for the deep seated tumors has not been satisfactory. We developed the radiofrequency capactive hyperthermia device (Greenytherm-GY8) in cooperation with Yonsei Cancer Center and Green Cross Medical Corporation. It was composed with $8{\sim}10MHz$ RF generator, capacitive electrode, matching system, cooling system, temperature measuring system and control PC computer. The thermal profile was investigated in agar phantom, animals and in human tumors, heated with capactivie RF device. Deep and homogeneous heating could be achieved in a large phantom of 25cm diameter and 19cm thick when heated with a pair of 23cm diameter electrodes, coupled to both bases of the phantom, when the size of the two electrodes was not the same, the region near the smaller electrode was preferentially heated. It was, therefore, possible to control the depth of heating by choosing proper size of electrodes. Therapeutic temperature $(42^{\circ}C{\sim}43^{\circ}C)$ could be obtained in the living animal experiments. Indications are that deep heating of humn tumors might be achieved with the capacitive method, provided that subcutaenous fat layer is cooled by temperature controlled bolus and large size of electrodes.

• Journal of the Korean Arthroscopy Society
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• v.3 no.1
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• pp.54-61
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• 1999

The current treatment of extensive meniscal injuries has resulted in numerous investigations and clinical trials to restore normal meniscal functions. A cryopreserved meniscal allograft transplantation is one of the successful methods available to restore the meniscus. All the procedures of 26 cases were performed in an minimal open fashion, though initial four cases were done with the aid of arthroscope. In all of the grafts, we used a bone bridge which was attached to meniscus for better stability and healing. Anterior cruciate ligament reconstructions were also performed simultaneously with the meniscal procedures. We attempted to minimize articular cartilage by employing so called the "Key-hole technique" for the medial meniscus transplantation. First, the meniscal cartilage bone bridge was shaped into a cylinder and a bone tunnel was made just beside the medial border of the anterior criciate ligament insertion of the recipient knee joint, and the bone bridge of the meniscal cartilage was push to press-fit. The inserted meniscal cartilage was sutured by the usually employed technique under arthroscopic control. The lateral meniscus was shaped different to the medial meniscus in that the bone bridge was semicylindrical and the bone trough was made beside the lateral border of the anterior criciate ligament insertion of the recipient knee joint. The meniscus was put into the bone trough and the leading suture was extracted anterior to the tibia and tied the knot. The inserted meniscus was sutured in the same manner as the medial meniscus transplantation. By the above described method, the authors were able to minimize the articular cartilage invasion and transplant the meniscus with relative accuracy.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.205-215
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• 2013

In digital imaging system, Bayer pattern is widely used and the observed image is degraded by optical blur during image acquisition process. Generally, demosaicing and deblurring process are separately performed in order to convert a blurred Bayer image to a high resolution color image. However, the demosaicing process often generates visible artifacts such as zipper effect and Moire artifacts when performing interpolation across edge direction in Bayer pattern image. These artifacts are emphasized by the deblurring process. In order to solve this problem, this paper proposes a deblurring algorithm combined with edge directional color demosaicing method. The proposed method is consisted of interpolation step and region classification step. Interpolation and deblurring are simultaneously performed according to horizontal and vertical directions, respectively during the interpolation step. In the region classification step, characteristics of local regions are determined at each pixel position and the directionally obtained values are region adaptively fused. Also, the proposed method uses blur model based on wave optics and deblurring filter is calculated by using estimated characteristics of local regions. The simulation results show that the proposed deblurring algorithm prevents the boosting of artifacts and outperforms conventional approaches in both objective and subjective terms.

• Geophysics and Geophysical Exploration
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• v.17 no.1
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• pp.34-44
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• 2014

Because offshore plant industry needs to design, deploy and operate much of equipment especially, the latest trend shows the installation of production facilities is augmented in the subsea. The installed facilities are very difficult to be repaired or changed because they are located in the subsea. For solving these problems, both the directly related information of the production like the optimal number, position and depth of wells and the distribution for effective operation and safety of equipment of subsea should be considered at the preliminary stage of FEED (Front End Engineering Design). The marine exploration is introduced in this paper for providing the fundamental technology to answer the questions related to above considering points. First, some kinds of the offshore plant facilities are enumerated and aims of marine exploration for the offshore oil/gas development are summarized. In addition to it, the main roles of marine survey, in the step of designing and installing offshore oil-gas plant, development are briefly listed. And then foreign examples are shown to help the reader's understand. This paper is hoped to be helpful for understanding the marine exploration that can be applied to offshore oil/gas plant and to be contributed to developing the domestic techniques in this field for the future.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1111-1117
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• 1996

Structural deterioration of the bioprosthetic xenograft valves due to primary tissue failure occurs in two modes: from fatigue lesions with tear and wear with or without calcification and from calcification with obstruction. Two groups of consecutive 56 patients with the Hancock porcine ortic valve(HM) and of 1 13 patients with the standard-profile onescu-Shiley bovine pericardial valve(ISM) explanted from mitral position at the time of re-replacement surgery for primary tissue failure at Seoul national University Hospital until 1994, were studied for clinical and pathological features. Their ages at primary implant were 31.9 $\pm$9.2 years In HM and 30.4$\pm$ 12.5 years in ISM. Hemodrnamic dysfunction of the failed mitral bloprostheses were predominantly insufficiency in HM(64.3%) and stenosis in ISM(51.3%)(p<0.001). Pathologic findings of the explanted mitral valves reflected these hemodynamic changes, revealing failure more often from tissue damage(tears and wears) in HM and more often from calcification in ISM(p< 0.001). Explant period(from primary implant to explant) was relatively short in ISM(8.7$\pm$2.6years), compared with the one in HM(10.4 $\pm$2.6 years)(p<0.001). In conclusion, both the Hancock and the lonescu-shiley valves would fail from calcification as well as issue damage. However, while the Hancock porcine valves in mitral position failed more frequently from tissue failure and insufficiency, the standard-profile lonescu-Shiley pericardial valves did from calcification and stenosis, especially in young pAtients . Although the possibility of less occurrence of valve failure from mechanical reasons may be expected with newer generation bloprostheses, it does not seem to Improve durability significantly unless further refinement in antimineralization is achieved. Therefore, clinical use of the glutaraldehyde-treated bioprosthetic valves is, at present, limited to the patients of advanced age groups.

• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.69-79
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• 1983

To develope the fundamental models suitable for slope stabilization and scenic effect improvement of the roadside slopes, this study has continuously been conducted for last about 10 years through the field survey and observations on the roadside slopes of 100 plots located in the Capital region. The results obtained could be summarized as follows: 1) In general, due to unsuitable treatments and constructions to the man-made bare slope characteristics of the roadsides, the treatment aims for stabilizing and improving the scenic beauty of the slopes have not been successfully reached in the surveyed regions. 2) Particularly, because of insufficiency of the follow-up maintenance techniques to the roadside slopes treated, denudations of slope scenery established as well as the withering of the vegetation planted have been accelerated for the most part of the slopes treated. 3) 6 fundamental models for the roadside slope treatments have been developed and could be edaptable to the nation-wide purposes. The fundamental models are the model of forest scenery match plantation, roadside scenery establishment, denuded land rehabilitation, rock slope greenification, absolute stabilization, and environmental plantation belt establishment, respectively.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.261-271
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• 2003

A condition evaluation procedure for the pavement foundations using multi-load level Falling Weight Deflectometer(FWD) deflections is presented in this paper. A dynamic finite element program incorporating a stress-dependent material model, was used to generate the synthetic deflection database. Based on this synthetic database, the relationships between surface deflections and critical responses, such as stresses and strains in base and subgrade layers, have been established. FWD deflection data, Dynamic Cone Penetrometer(UP) data, and repeated load resilient modulus testing results used in developing this procedure were collected from the Long Term Pavement Performance (LTPP) and North Carolina Department of Transportation (NCDOT) database. Research effort focused on investigation of the effect of the FWD load level on the condition evaluation procedures. The results indicate that the proposed procedure can estimate the pavement foundation conditions. It is also found that structurally adjusted Base Damage Index (BDI) and Base Curvature Index (BCI) are good indicators for the prediction of stiffness characteristics of aggregate base and subgrade respectively. A FWD test with a load of 66.7 kN or less does not improve the accuracy of this procedure. Results from the study for the nonlinear behavior of a pavement foundations indicate that the deflection ratio obtained from multi-load level deflections can predict the type and quality of the pavement foundation materials.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.1
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• pp.48-61
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• 1989

In this paper, two-dimensional numerical simulation of GaAs MESFFT with 0.7${\mu}m$ gate length is perfomed. Drift-diffusion model which consider that mobility is a function of local electric field, is used. As a discretization method, instead of FDM (finite difference method) and FEM (finite element method), the Control-Volume Formulation (CVF) is used and as a numerical scheme current hybrid scheme or upwind scheme is replaced by power-law scheme which is very approximate to exponential scheme. In the process of numerical analysis, Peclet number which represents the velocity ratio of drift and diffusion, is introduced. And using this concept a current equation which consider numerical scheme at the interface of control volume, is proposed. The I-V characteristics using the model and numerical method has a good agreement with that of previous paper by others. Therefore, it is confined that it may be useful as a simulator for GaAs MESFET. Besides I-V characteristics, the mechanism of both velocity saturation in drift-diffusion model is described from the view of velocity and electric field distribution at the bottom of the channel. In addition, the relationship between the mechanism and position of dipole and drain current, are described.