• Korean Journal of Bronchoesophagology
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• v.13 no.1
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• pp.39-42
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• 2007

Esophageal duplication cyst is very rare mediastinal tumor which is congenital lesion of the esophagus. Esophageal duplication cyst could be excised with video assisted thoracoscopic surgery(VATS) if it is relatively small, cystic lesion and not adhered severely to the surrounding tissues such as lung, trachea, bronchus, esophagus and pleura. We report a case of an esophageal duplication cyst which was located in the right thoracic cavity below carina and could be excised completely and repaired by interrupted suture with 3.0 black silk. The patient was discharged at 10 days after operation with good condition and has been in uneventful condition 2 months after operation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.3
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• pp.579-586
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• 1999

In this paper, we have analyzed a performance of fast frequency hopping communication systems when a rayleigh fading caused by envelope variations of a signal received in multipath channel is, but it is not considered that intentional or unintentional jamming can be. The multipath fading channel and rayleigh fading are confirmed by theoretical analysis. In fading or non-fading, the performance of this system is studied. When the path diversity is applied to this system, the performance is shown to be superior to non-diversity systems about 20dB. For modulation methods, BFSK was compared with DPSK.

• Korean Journal of Bronchoesophagology
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• v.8 no.1
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• pp.61-65
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• 2002

Background : Acquired tracheoesophageal fistula(TEF) results mostly from Prolonged tracheal intubation and insertion of nasogastric tube. Although the incidence has decreased since the usage of low pressure, high volume cuff of endotracheal tube, it is seldom cured spontaneously and needs surgical treatment. Material and Methods : We have retrospectively reviewed five cases of TEF who underwent surgical treatment for cure from March, 1990 to September, 2001 and analyzed the cause, treatment, postoperative complications and prognostic factors. Results : Majority were men(80% : 4 of 5 patients) and the mean age was 29.4 years old(range, 11-58). The most predominant etiology was prolonged intubation or tracheostomy(80% : 4 of 5 patients) and 3 of 5 patients were treated by tracheal resection and end to end anastomosis with primary closure of esophagus. Postoperative complications occurred in 4 patients the most common complications were wound infection(4 cases) and esophageal leakage(2 cases). Extubation was done on postoperative day 11.5(range, 1-33) days, and factors causing delayed extubation were status esophagus. epilepticus, edema, and tracheal stenosis. Conclusion : Spontaneous closure of TEF is seldom possible and the surgical treatment of choice is tracheal resection and end to end anastomosis with primary repair of the esophagus. preoperative pulmonary rehabilitation and early extubation postoperatively are important factors for success.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.9 s.90
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• pp.891-896
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• 2004

'Coil' occupies very much important position in delivering driving force of optical pick-up actuators. Up to now the main stream has been a winding coil type actuator, but actuators using FP-Coil(fine pattern coil) have been considered for the more compacted and simple manufacturing process and have variously spreaded the application fields by product. We have tried to design actuators using PCB-Coil(printed circuit board coil) which has benefits in terms of price and manufacturing process. Especially this research has two main things to reduce the vibration of sub-resonance and to assure the DC sensitivity among the performances of asymmetric optical pick-up actuator with PCB-Coil.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.70-77
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• 2010

This paper presents the current and speed controller design procedure and their performance for the IPMSM based next generation high speed railway traction system. The next generation high speed railway system is a power distributed type and uses vector control method for a motor speed control. Since the speed and current controller gains of the vector control system directly affects to the transient characteristics and speed control capability, the systematic design of the controllers are required. In this paper the controllers are designed using the IPMSM based next generation high speed railway system parameters. Simulation programs based on Matlab/Simulink is developed. Finally the controller characteristics are analyzed by the simulation results.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.393-399
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• 2003

This paper describes a proper criterion for the constant rate of loading consolidation (CRLC) test which is a kind of the continuous loading consolidation(CRLS) and widely used as alternative methods to the incremental loading consolidation(ILC)test. With those results, the preconsolidation pressure estimated by the CRLC test turned out to be comparatively larger than that of the ILC test and it is increased in proportion to the applied loading rates. However, the compression index in the CRLC test is less ifluenced on by the loading rates. The coeffcient of consolidation and permeability in the CRLC test are dependent on excess pore pressure ratio mainly. In other words, if the pore pressure ratios are too low, the coefficient of consolidation and permeability become smaller than those of the ILC test. On the other hand, if the excess pore pressure ratios are too high, the coefficient of consolidation and permeability become so larger than those of the ILC test. Therefore loading rates should be carefully determined to generate proper excess pore pressure ratio.

• The Korean Journal of Zoology
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• v.15 no.3
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• pp.105-110
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• 1972

A cellulosse acetate electrophoretic survey of Korean Anura has revealed the presence of diverse lactate and malate dehydrogenase (LDH and MDH) isozymes. The pattern of LDH and MDH isozymes in the tissues of the central nervous system of the six species of Anura examined are species specific and differ from those of mammals and birds. Both Rana nigromaculata nigromaculata and Rana nigromaculata coreana have two molecular forms of LDH and MDH, respectively, with almost the same pattern. Whole brain homogenate of Rana temporaria shows also a maximum of only two LDH isozymes. Both Bufo bufo asiaticus and Bombina orientalis have five molecular forms of LDH with an entirely different spacing on the zymograms, whereas Rana rugosa has three. Two molecular forms of MDH are present in all animals examined and one band is shown in olfactory lobe and mixture of cerebellum and medulla oblongata of Rana nigromaculata nigromaculata.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.515-518
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• 2002

콘트롤밸브는 지역 냉${\cdot}$난방 및 APT, 대형 빌딩의 냉온수, 중온수 및 공조배관 시스템에 사용되어 유체적 바란스를 이루는데 사용된다. 이와같이 유체의 흐름을 조절하기 위하여 사용되는 콘트롤 밸브가 때로는 소음 문제를 일으키기도 한다. 최근 들어 밸브의 소음이 문제가 되는 경우가 빈번해 지고 있다. 밸브의 기본적 기능을 충족시키기 위해서는 영구적인 수두 손실이 필요하며 이러한 수두손실을 발생시키는 과정에서 유체 흐름에 의해 발생한 난류가 커다란 밸브 소음을 유발하게 된다. 본 연구에서는 콘트롤 밸브 소음 특성 평가 방법을 검토하였다. 밸브 및 배관으로 이루어진 시스템에서 발생되는 소음을 예측하는 절차를 살펴보았다. 밸브의 음향 파워레벨을 측정하고 유량 및 차압의 변화에 따른 소음 예측식을 결정 하였다. 본 연구에서 제시한 밸브 소음 측정 방법은 새로운 밸브의 소음특성 평가, 밸브 소음의 예측 그리고 서로 다른 밸브 사이의 성능비교 등에 사용될 수 있을 것이다.

• Journal of Chest Surgery
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• v.37 no.5
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• pp.456-459
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• 2004

A 16 month old male infant was found with slip down state in a bath room without evidence of trauma to whole body. The infant was treated with several thoracentesis and closed drainage due to persistent right pleural effusion at other hospital and transferred to our hospital for further evaluation and treatment at July 2003. The pleural effusion was confirmed as chylothorax by chemical analysis. He was treated with parenteral feeding for 21 days. Because the amount of chest tube drainage was about 110∼210 cc/day, and could not be decreased with conservative treatment. patients underwent ligation of thoracic duct. Post-operative course was uneventful except post-op. empyema thoracis, The open drainage tube was removed at post operative 30 days, The patient was in very good condition with complete cure until post-operative 3 months.

• Food Science and Industry
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• v.50 no.3
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• pp.33-38
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• 2017

One noticeable thing about the recently opened 'Starfield Hanam' and 'Hyundai Department Store (Pangyo)' is consumer's interest and positive response to their hosted food brands ranging from restaurants, dessert cafes and coffee shops. Department store and shopping complex, so-called aggregation of lifestyle are making the most out of food brands as a differentiation strategy and consumer's interest on it act as a barometer for current consumption trend. Along with the high interest on food market, changes in lifestyle, such as increasing ratio of two or less households, advent of multiple communication channels as SNS, deluge of information and gradually developing individualism, are creating needs for convenient but high quality eating culture. This need contributed in transforming the product family which was once famous as 'Instant Food' into a 'Home Meal Replacement (HMR)'. Since local food companies are striving to keep pace with the trend and actively penetrating HMR market, regardless of long-term recession, the Korean domestic food market is steadily growing with a bright future.