• Journal of Chest Surgery
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• v.42 no.3
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• pp.337-343
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• 2009

Background: Postoperative recurrence is a major problem after performing video-assisted thoracic surgery for the treatment of primary pneumothorax. This study was designed to evaluate the efficacy and safety of a bioabsorbable staple line reinforcement (GORE $SEAMGUARD^{(R)}$) for preventing recurrence after bullectomy. Material and Method: From January 2000 to December 2004, 300 patients underwent video assisted thoracoscopic surgery for the treatment of primary penumothorax. 143 patients were treated with bioabsorbable staple line reinforcement (Group A) and 142 patients were treated with stapling of the bullae (Group B). Mechanical pleural abrasion was performed in all the patients. The operating time, the duration of the indwelling chest tube, the length of the hospital stay and the number of recurrences after operation were compared between the groups. Result: No operative deaths occurred. The conversion rate to an open procedure was 5% (15/300). Comparison with these groups (Group A versus Group B) showed the following results: the operating time ($49.6{\pm}25.6$ vs $51.8{\pm}30.4$ minutes, respectively, p=0.514), the duration of an indwelling chest tube ($5.8{\pm}2.5$ vs $7.2{\pm}3.3$ days, respectively, p<0.005), the hospital stay ($10.9{\pm}4.3$ vs $12.5{\pm}4.3$ days, respectively, p<0.005) and the number of recurrences (14 (9.8%) vs 10 (7.0%), respectively, the over all rate: 8.4% p=0.523), and the mean follow up period. ($48.1{\pm}36.6$ vs $36.5{\pm}24.4$ months, respectively). Conclusion: There were advantages to use synthetic absorbable staple line reinforcement over the usual method for the treatment of primary pneumothorax in regard to the duration of an indwelling chest tube and the hospital stay, but here was no significant difference between the groups for postoperative recurrence.

• Journal of the Korean Geosynthetics Society
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• v.17 no.2
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• pp.41-49
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• 2018

The purpose of this study is to fabricate a full scale road embankment using lightweight air foamed soil as a soil material on soft ground and to investigate its material characteristics and behavior in order to promote dredged soil utilization and minimize ground improvement. As a result of the laboratory test of the onsite mixed samples, the total unit weight of the specimens decreased almost linearly until curing 28 days. In particular, the total unit weight after 28 days of curing was reduced to about 81% of the slurry state before curing, which will be useful in the formulation of similar native soil materials in the future. The unconfined compressive strength began to decrease with the 14th day of curing as shown in the previous study. When the cement content is increased, the strength decreases sharply at a small strain change after the occurrence of the maximum compressive strength, and the maximum strength is exhibited in a range of a smaller axial strain than normal range. The settlement at the surface layer of the ground due to the lightweight embankment was about 1 / 2.75 of the soil embankment and was in agreement with the unit weight ratio (1 / 2.7) of the embankment materials. This indicates the cause and effect of the settlement due to the difference in self weight of the embankments. Also, the difference in settlement between soil and lightweight embankment increased with increasing depth. This shows that the difference in the point at which the settlement is terminated is clear. The ground horizontal displacement under the lightweight embankment was about 15~20% smaller than that of the soil embankment and the depth of occurrence was also 4.5~5.0m shallower in the lightweight embankment.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.451-464
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• 2008

Three-phase inverse fluidized bed has been widely adopted with its increasing demand in the fields of bioreactor, fermentation process, wastewater treatment process, absorption and adsorption processes, where the fluidized or suspended particles are small or lower density comparing with that of continuous liquid phase, since the particles are frequently substrate, contacting medium or catalyst carrier. However, there has been little attention on the three-phase inverse fluidized beds even on the hydrodynamics. Needless to say, the information on the hydrodynamics and transport phenomena such as heat and mass transfer in the inverse fluidized beds has been essential for the operation, design and scale-up of various reactors and processes which are employing the three-phase inverse beds. In the present article, thus, the information on the three-phase inverse fluidized beds has been summarized and reorganized to suggest a pre-requisite knowledge for the field work in a sense of engineering point of view. The article is composed of three parts; hydrodynamics, heat and mass transfer characteristics of three-phase inverse fluidized beds. Effects of operating variables on the phase holdup, bubble properties and particle fluctuating frequency and dispersion were discussed in the section of hydrodynamics; effects of operating variables on the heat transfer coefficient and on the heat transfer model were discussed in the section of heat transfer characteristics ; and in the section of mass transfer characteristics, effects of operating variables on the liquid axial dispersion and volumetric liquid phase mass transfer coefficient were examined. In each section, correlations to predict the hydrodynamic characteristics such as minimum fluidization velocity, phase holdup, bubble properties and particle fluctuating frequency and dispersion and heat and mass transfer coefficients were suggested. And finally suggestions have been made for the future study for the application of three-phase inverse fluidized bed in several available fields to meet the increasing demands of this system.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.11a
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• pp.20-20
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• 2001

우리나라 제지산업은 화학펼프의 80%를 수입에 의존하고 었으나 고지회수율 및 이용율이 세계적으로 볼 때 매우 높은 환경친화적 산업이다. 고지 재활용 공정 중에 서 가장 핵심적인 공정인 부유부상 공정은 고상계의 표면특성 차이를 이용하여 소수성 의 잉크업자를 기포에 부착시켜 부상을 통하여 제거하는 공정이다. 고지 사용의 고도화 를 위해서는 부유부상 공정의 효율 증대가 절실히 요구되고 있다. 또한 부유부상 공정 의 핵심적인 인자로 부유부상을 통하여 제거되는 고형물질의 표면 특성 특히 소수화도 가 중요하다는 것은 보고된 바 있으나 부유부상에 필요한 표면 특성의 존재 여부와 표 면 에너지와 부유부상 효율의 관계 등에 관한 기본적인 연구가 더욱 필요한 실정이다. 이에 본 연구에서는 부유부상 공정을 기초과학적 측면에서 규명하기 위해 마 이 크로 크리 스탈린 셀룰로오스(Microcrystalline cellulose: MCC)를 모델 물질로 사용하 고 이들의 표면특성을 접촉각 측정을 통하여 평가하였다. 친수성의 표면 특성을 지닌 M MCC의 표면 특성을 소수성으로 바꾸기 위하여 AKD(alkyl ketene dimer)의 함량별로 사이징 처리하여 소수성을 지닌 잉크를 모벨링 하고 친수성 MCC를 염색시약을 이용 하여 흑색으로 염색함으로써 소수화 된 MCC와의 색차를 두어 섬유를 모델링 하였다. 이렇게 제조된 MCC의 소수화 정도를 평가하기 위하여 분말상태인 MCC를 pellet으로 제조하여 각기 다른 표면장력과 표변특성을 지난 용액을 이용하여 Advancing Contact A Angle을 측정하고 다양한 방법으로 이를 분석하여 시료의 표면에너지를 평가하였다 그 리고 부유부상 셀내의 액상의 이온강도와 표면장력 등 화학적인 인자에 의한 부유부상 분리효과를 평가하였다.있었다 (그림 2). 칼렌다는 종이를 높은 전단력과 압축력으로 변형시키는데 비해 도침은 단순히 압축 압력만을 종이에 가하는 것이 다르다고 볼 수 있는데, 라 이너지와 백상지가 같은 조건하에서 왜 이러한 큰 차이를 보이는 이유를 아직 알수 없다.해 동일한 공정 데이터들올 이용하여 보편적으로 사용하는 통계기법 중의 하나인 주성분회귀분석을 실시하였다. 주성분 분석은 여러 개의 반응변수에 대하여 얻어진 다변량 자료의 다차원적인 변 수들을 축소, 요약하는 차원의 단순화와 더불어 서로 상관되어있는 반응변수들 상호간 의 복잡한 구조를 분석하는 기법이다. 본 발표에서는 공정 자료를 활용하여 인공신경망 과 주성분분석을 통해 공정 트러블의 발생에 영향 하는 인자들을 보다 현실적으로 추 정하고, 그 대책을 모색함으로써 이를 최소화할 수 있는 방안을 소개하고자 한다.금 빛 용사 둥과 같은 표면처리를 할 경우임의 소재 표면에 도금 및 용 사에 용이한 재료를 오버레이용접시킨 후 표면처리를 함으로써 보다 고품질의 표면층을 얻기위한 시도가 이루어지고 있다. 따라서 국내, 외의 오버레이 용접기술의 적용현황 및 대표적인 적용사례, 오버레이 용접기술 및 용접재료의 개발현황 둥을 중심으로 살펴봄으로서 아직 국내에서는 널리 알려지지 않은 본 기 술의 활용을 넓이고자 한다. within minimum time from beginning of the shutdown.및 12.36%, $101{\sim}200$일의 경우 12.78% 및 12.44%, 201일 이상의 경우 13.17% 및 11.30%로 201일 이상의 유기의 경우에만 대조구와 삭제 구간에 유의적인(p<0.05) 차이를 나타내었다.는 담수(淡水)에서 10%o의 해수(海水)로 이주된지 14일(日) 이후에 신장(腎臟)에서 수축된

• Food Science of Animal Resources
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• v.21 no.4
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• pp.349-357
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• 2001

The effects of dietary conjugated linoleic aicd on pork quality was investigated using sixty four pigs. CLA was synthesized by alkaline isomerization method with corn oil. Pigs were devided into 4 treatment groups(16 pigs/group) arid subjected to one of four treatment diets(0, 0.1, 0.2, and 0.3% CLA diets) for 2 weeks before slaughter. Pork loin and belly were collected from the animals(105∼110kg body weight) slaughtering at the commercial slaughter house. Pork loin and belly meat were aerobic packaged and then stored during 2. 5. 8. 11 and 13 days at 4$\^{C}$ refrigerator. Samples were analysed for meat color, texture and sensory characteristics. There were no diference in meat color(L*, a*, b*), texture and sensory property among control and CLA treatment (s), and no changes as the storage period passed. This results mean that feeding CLA to pork doesn't change the meat color and texture of the pork what consumers consider when they buy some meat. Especially, feeding CLA to pork didn't transform sensory property of the pork. We considered these result as no problem in the pig fed with CLA.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.137-147
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• 1999

Fluidized-bed thermal desorber coupled with a heat pipe was investigated for the remediation of soil contaminated with diesel oils. Thermal gravimetric analysis by Cahn-balance indicated that the desorption of diesel oils from the soil particles was mainly governed by the internal diffusion at low concentration of less than 0.5 wt. % of oils in the soil particles. In fluidized-bed experiments. increase of fluidizing gas velocity reduced the residual oils of the contaminated soils, the increase of soil feed rate decreased efficiency of fluidized-bed desorber. A mathematical model was developed by incorporating Fickian diffusion kinetics into the Kunii-Levenspiel model Simulation results showed reasonable agreement for the performance of fluidized-bed thermal desorber.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.255-260
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• 1992

A procedure for spectrophotometric determination of traces of phosphorus(P) in high-purity trichlorosilane(TCS) is proposed using an adsorptive separation. $PCl_3$, which is a dominant P impurity within TCS, is first oxidized by oxygen to a stable form as $POCl_3$. $AlCl_3$ is selected as an adsorbent which forms a thermally stable complex with $POCl_3$ in TCS and can be well dissolved in aqueous ethanol solution. The proposed adsorptive separation method is free from the formation of silica gel and gas bubbles during the colorimetric analysis of TCS. The method reveals that the P concentration in a semiconductor-grade TCS is 5.32 ${\mi}g/l$ within the standard deviation of ${\pm}$ 17%. On the other hand, the P concentration of the purified TCS which is separated from the $AlCl_3$${\cdot}$$POCl_3$ complex is reduced to be less than 0.15 ${\mi}g/l$, showing the efficient applicability of $AlCl_3$ to the wet chemical analysis. The proposed method is also tested to verify the effectiveness of other well-known adsorbents.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.106-113
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• 2008

This study investigated the effects of gamma irradiation on microbial, physical, and sensory qualities as well as the antioxidant activity of cooked spinach. At 3 kGy of gamma irradiation, microbial growth was inhibited until 4 weeks and 5 days at storage temperatures of 4 and $25^{\circ}C$, respectively. The dose of 2 kGy did not significantly affect hardness; however, Hunter color system values for lightness, redness, and yellowness were changed. Low dose gamma-irradiation (up to 2 kGy) did not significantly affect the antioxidant activity of the cooked spinach. Also, based on a triangle sensory test, the gamma-irradiated cooked spinach was not significantly different from the control. These results, suggest that applying gamma irradiation to cooked vegetables at doses lower than 2 kGy can be recommended to extend shelf-life and maintain quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1292-1296
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• 2003

The purpose of this study is to investigate the changes of physico-chemical properties of chilled plaice muscle, stored at 4$^{\circ}C$ for 0 ∼ 21 days, with different packaging methods (vacuum packaged with PVDC and aerobic packaged with HDPE). pH value in aerobic packaged plaice muscle (APPM) decreased from 6.3 to 6.09 at first 2 day storage, and then increased gradually during storage time. Although pH pattern of vacuum packaged plaice muscle (VPPM) was similar to that of APPM, change of pH value during storage time was slower and lower than APPM. VBN value in aerobic packaged one increased during storage time. Especially it increased significantly after 7 days of storage. While VBN value in VPPM increased only a little to 14 days. TBA value showed significant difference between APPM and VPPM. WHC of APPM was higher than that of VPPM after 7 days of storage. In electrophoretic pattern of myofibril of APPM stored for 14 days hydrolysis of heavy chain and tropomyosin was observed. However, in VPPM, some hydrolysis occurred only in heavy chain. SDS-PAGE analysis showed that hydrolysis of VPPM occurs later than that of APPM.

• Sleep Medicine and Psychophysiology
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• v.12 no.1
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• pp.64-67
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• 2005

Obstructive sleep apnea syndrome(OSAS) is a common disease in the field of otorhinolaryngology and is characterized by repeated upper airway occlusions occurring during sleep. OSAS can occur due to various etiologies of the nasal, oral, pharyngeal and laryngeal airway in adults. Nasal obstruction can be caused by septal deviation, nasal polyps, concha bullosa, choanal atresia, neoplasms, foreign body, postoperative/post-traumatic synechiae, various rhinitis and so on. There are various kinds of surgical treatment of OSAS including nasal surgery, LAUP, UPPP, surgery of tongue base, tracheostomy and so on, but the effect of nasal surgery on snoring and OSAS is controversial. The authors report the case of a patient who had experienced nasal obstruction, moderate snoring and OSAS and who improved after septoplasty and turbinoplasty.