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Minimally invasive surgery for submucosal(subepithelial) tumors of the stomach

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World Journal of Gastroenterology 2014年第36期20卷 13035-13043页

作者： Chang Min lee hyung-Ho Kim Department of Surgery Seoul National University Bundang Hospital Seongnam 463-707 South Korea Colledge of Medicine Seoul National University Seoul 110-799 South Korea

Minimally invasive surgery has become common in the surgical resection of gastrointestinal submucosal tumors(SMTs). The purpose of this article is to review recent trends in minimally invasive surgery for gastric SMTs. Although laparoscopic resection has been main stream of minimally invasive surgery for gastrointestinal SMTs, recent advances in endoscopic procedures now provide various treatment modalities for gastric SMTs. Moreover, investigators have developed several hybrid techniques that include the advantages of both laparoscopic and endoscopic procedure. In addition, several types of reduced port surgeries, modification of conventional laparoscopic procedures, have been recently applied to the surgical resection of SMTs. Meanwhile, robotic surgery for SMTs requires further evidence and improvement.

关键词： Minimally invasive Surgery Submucosal tumor Gastrointestinal tract

Effect of ammonia gas etching on growth of vertically aligned carbon nanotubes/nanofibers

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 130-134页

作者： Sang-Gook KIM Sooh-Yung KIM hyung-Woo lee Department of Mechanical Engineering Massachusetts Institute of Technology 77 Massachusetts Ave Cambridge MA 02139 USA National Core Research Center for Hybrid Materials Solution Pusan National University

The etching effect of ammonia （NH3） on the growth of vertically aligned nanotubes/nanofibers （CNTs） was investigated by direct-current plasma enhanced chemical vapor deposition （DC-PECVD）. NH3 gas etches Ni catalyst layer to form nanoscale islands while NH3 plasma etches the deposited amorphous carbon. Based on the etching effect of NH3 gas on Ni catalyst, the differences of growing bundles of CNTs and single strand CNTs were discussed; specifically, the amount of optimal NH3 gas etching is different between bundles of CNTs and single strand CNTs. In contrast to the CNT carpet growth, the single strand CNT growth requires shorter etching time （5 min） than large catalytic patterns （10 rain） since nano dots already form catalyst islands for CNT growth. Through removing the plasma pretreatment process, the damage from being exposed at high temperature substrate occurring during the plasma generation time is minimized. High resolution transmission electron microscopy （HTEM） shows fishbone structure of CNTs grown by PECVD.

关键词： carbon nanotube ammonia etching nickel catalyst plasma enhanced chemical vapor deposition (PECVD)

Flow and mass balance analysis of eco-bio infiltration system

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 612-619页

作者： Maria C. MANIQUIZ lee-hyung KIM Soyoung lee Jiyeon CHOI Department of Civil and Environmental Engineering Kongju National University 275 Budaedong Seobuk-gu Cheonan City Chungnam-do 330-717 R. O. Korea

A structued stormwater infiltration system was developed and constructed at a university campus and monitoring of storm events was performed during a one- year operation period. The flow and pollutant mass balances were analyzed and the overall efficiency of the system was assessed. While significant positive correla- tions were observed among rainfall, runoff and discharge volume （R2= 0.93-0.99; p 〈 0.05）, there was no sig- nificant correlations existed between rainfall, runoff, discharge volume and pollutant load. The system was more effective in reducing the runoff volume by more than 50% for small storm events but the difference between the runoff and discharge volume was significant even with rainfall greater than 10ram. Results showed that the pollutant reduction rates were higher compared to the runoff volume reduction. Average pollutant reduction rates were in the range of 72% to 90% with coefficient of variation between 0.10 and 0.46. Comparable with runoff reduction, the system was more effective in reducing the pollutant load for small storm events, in the range of 80% to 100% for rainfall between 0 and 10mm; while 65% to 80% for rainfall between l0 and 20mm. Among the pollutant parameters, particulate matters was highly reduced by the system achieving only a maximum of 25% discharge load even after the entire runoff was completely discharged. The findings have proven the capability of the system as a tool in stormwater manage- ment achieving both flow reduction and water quality improvement.

关键词： best management practice flow balance lowimpact development mass balance nonpoint source,stormwater runoff

Effective parameters on diameter of carbon nanotubes by plasma enhanced chemical vapor deposition

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中国有色金属学会会刊：英文版 2012年第S3期22卷 712-716页

作者： Kang Young JEONG Hyun Kyung JUNG hyung Woo lee National Core Research Center for Hybrid Materials Solution Hybrid Graduate SchoolPusan National University Department of Diagnostic Radiology Inje University College of MedicineHaeundae Paik Hospital

The effective parameters on the diameter of carbon nanotubes (CNTs) by plasma enhanced chemical vapor deposition (PECVD) were *** lots of influential parameters,the effects of the catalytic film thickness and the pretreatment plasma power on the growth of CNTs were *** results show that the size of catalytic islands increases by increasing the thickness of catalytic layer,but the density of CNTs *** pretreatment duration time of 30 s is the optimal condition for growing CNTs with about 50 nm in *** increasing the pretreatment plasma power,the diameter of CNTs decreases ***,the diameter of CNTs does not change drastically from 80 to 120 *** uniformly grown CNTs with the diameter of 50 nm are obtained at the pretreatment plasma power of 100 W.

关键词： carbon nanotubes catalytic film thickness pretreatment plasma power plasma enhanced chemical vapor deposition

Development of single-action,two-step clinching system using finite element analysis

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中国有色金属学会会刊：英文版 2009年第B9期19卷 266-270页

作者： Seong-Wook lee Tae-hyung KIM Geun-Jo HAN Power & Industrial Systems R&D Center Hyosung Corporation Department of Mechanical Engineering Department of Mechanical Engineering Dong-A University

Traditional manufacturing processes for bending and combining the upper and lower heat insulation plates for a car catalytic converter need two kinds of bending dies. This study was carried out to develop a single-action, two-step clinching system for clinching heat insulation plates. To design the operating mechanism for this clinching system, finite element analysis was used to estimate the bending load needed and to predict the bent shape of the heat insulation plate. Then a recovery and cushioning system was designed for the bending die. It is expected that this new process will improve the manufacturing quality of heat insulation plates and will reduce manufacturing cost. And a higher value-added technique for mold and pressing systems was introduced.

关键词：缓冲系统有限元分析开发汽车催化转化器单动模具技术隔热板板弯曲

A review of C_1 chemistry synthesis using yttrium-stabilized zirconia catalyst

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Journal of Rare Earths 2008年第1期26卷 1-6页

作者： Antonius Indarto Jae-Wook Choi Hwaung lee hyung Keun Song Plasma-Catalyst Chemical Process

C1 chemistry based on synthesis gas, methane, and carbon dioxide offers many routes to industrial chemicals. The reactions related to the synthesis of gas can be classified into direct and indirect approach for making such products, such as acetic acid, dimethyl ether, and alcohol. Catalytic syngas processing is currently done at high temperatures and pressures, conditions that could be unfavorable for the life of the catalyst. Another issue of C1 chemistry is related to the methane-initiated process. It has been known that direct methane conversions are still suffering from low yields and selectivity of products resulting in unprofitable ways to produce products, such as higher hydrocarbons, methanol, and so on. However, many experts and researchers are still trying to find the best method to overcome these barriers, for example, by finding the best catalyst to reduce the high-energy barrier of the reactions and conduct only selective catalyst-surface reactions. The appli- cation of Yttria-Stabilized Zirconia （YSZ） and its combination with other metals for catalyzing purposes are increasing. The existence of an interesting site that acts as oxygen store could be the main reason for it. Moreover, formation of intermediate species on the surface of YSZ also contributes significantly in increasing the production of some specific products. Understanding the phenomena happening inside could be necessary. In this article, the use of YSZ for some C1 chemistry reactions was discussed and reviewed.

关键词： C1 chemistry methane synthesis gas methanol yttria-stabilized zirconia catalyst oxygen storage rare earths

Stability analysis for time delay control of nonlinear systems in discrete-time domain with a standard discretisation method

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Control Theory and Technology 2020年第1期18卷 92-106页

作者： Jinoh lee Gustavo A.MEDRANO-CERDA Je hyung JUNG Advanced Robotics Istituto Italian.di TecnologiaVia Morego 30Genoa16163Italy Tecnalia Research and Innovation Mikeletegi Pasealekua1-3E-20009Donostia-San SebastianSpain

This paper provides stability analysis results for discretised time delay control(TDC)as implemented in a sampled data system with the standard form of zero-order *** first substantiate stability issues in discrete-time TDC using an example and propose sufficient stability criteria in the sense of *** parameters significantly affecting the overall system stability are the sampling period,the desired trajectory and the selection of the reference model dynamics.

关键词： Time delay control(TDC) discretisation stability analysis zero-order hold

Decomposition of CCl_4 and CHCl_3 on gliding arc plasma

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Journal of Environmental Sciences 2006年第1期18卷 83-89页

作者： Antonius Indarto CHOI Jae-wook lee Hwaung SONG hyung-keun Korea Institute of Science and Technology Clean Technology Research Center P.O. Box 131 Cheongryang Seoul 130-650 Korea Korea Institute of Science and Technology Clean Technology Research Center P.O. Box 131 Cheongryang Seoul 130-650 Korea.

Decomposition of chlorinated hydrocarbons, CCl4 and CHCl3, in gliding plasma was examined. The effects of initial concentrations, total gas flow rates, and power consumption have been investigated. The conversion result was relatively high. It reached 80% for CCl4 and 97% for CHCl3. Using atmospheric air as the carrier gas, the plasma reaction occurred at exothermic reaction and the main products were CO2, CO, and Cl2. Transformation into CCl4 was also detected for CHCl3 decomposition reaction. The conversion of CCh and CHCl3 were increased with the increasing applied frequency and decreasing total gas flow rate.

关键词： plasma gliding arc CCl4 CHCl3 decomposition reaction

Milk protein-shelled gold nanoparticles with gastrointestinally active absorption for aurotherapy to brain tumor

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Bioactive Materials 2022年第2期7卷 35-48页

作者： hyung Shik Kim Seung Jae lee Dong Yun lee Department of Bioengineering College of Engineeringand BK FOUR Biopharmaceutical Innovation Leader for Education and Research GroupHanyang UniversitySeoul04763Republic of Korea Institute of Nano Science and Technology Hanyang UniversitySeoul04763Republic of Korea

Orally absorbable gold nanoparticles(AuNP)having cancer ablation therapy is strongly demanded to treat glioblastoma multiforme(GBM)for patients with its highest incidence ***,we develop a milk protein lactoferrin-conjugated AuNP for its oral absorption and targeting to the GBM through the interaction between lactoferrin(Lf)and lactoferrin receptor(LfR)that is highly expressed in the intestine,blood-brain barrier and *** stability and long circulation of AuNP,glutathione and polyethylene glycol(PEG)is introduced,which is called to *** Lf-PEG-AuNP are orally administered to orthotopic GBM-bearing mice,11-fold and 8-fold higher concentrations of AuNP are measured in bloodstreams and GBM in the brain,respectively,compared with ***,orally administered Lf-PEG-AuNP exhibit an outstanding temperature rise in GBM by irradiating laser and significantly reduce tumor ***,we suggest that the Lf-PEG-AuNP can fundamentally target GBM in the brain through oral absorption,and that its efficient photothermal therapy is possible.

关键词： intestine absorption gastrointestinal