• Journal of Chest Surgery
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• v.51 no.1
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• pp.29-34
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• 2018

Background: We evaluated the feasibility and outcomes of pulmonary resection and mediastinal node dissection (MND) by video-assisted thoracoscopic surgery (VATS) following neoadjuvant therapy for stage IIIA N2 non-small cell lung cancer (NSCLC). Methods: From November 2009 to December 2013, a total of 35 consecutive patients with pathologically or radiologically confirmed stage IIIA N2 lung cancer underwent pulmonary resection and MND, performed by a single surgeon, following neoadjuvant chemoradiation. Preoperative patient characteristics, surgical outcomes, postoperative drainage, postoperative complications, and mortality were retrospectively analyzed. Results: VATS was completed in 17 patients. Thoracotomy was performed in 18 patients, with 13 planned thoracotomies and 5 conversions from the VATS approach. The median age was $62.7{\pm}7.9years$ in the VATS group and $60{\pm}8.7years$ in the thoracotomy group. The patients in the VATS group tended to have a lower diffusing capacity for carbon monoxide (p=0.077). There were no differences between the 2 groups in the method of diagnosing the N stage, tumor response and size after induction, tumor location, or histologic type. Complete resection was achieved in all patients. More total and mediastinal nodes were dissected in the VATS group than in the thoracotomy group (p<0.05). The median chest tube duration was 5.3 days (range, 1 to 33 days) for the VATS group and 7.2 days (range, 2 to 28 days) for the thoracotomy group. The median follow-up duration was 36.3 months. The 5-year survival rates were 76% in the VATS group and 57.8% in the thoracotomy group (p=0.39). The 5-year disease-free survival rates were 40.3% and 38.9% in the VATS and thoracotomy groups, respectively (p=0.8). Conclusion: The VATS approach following neoadjuvant treatment was safe and feasible in selected patients for the treatment of stage IIIA N2 NSCLC, with no compromise of oncologic efficacy.

• Journal of Technology Innovation
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• v.22 no.4
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• pp.145-164
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• 2014

Nuclear fusion is one of the most promising options for generating large amounts of carbon-free energy in the future. Major countries such as China, EU, and Japan have established a national plan for DEMO construction and they are implementing it. Korea has started a nuclear fusion research and development by the KSTAR project started in 1995. There are matured needs for a full-scale research and development initiatives to ensure competition with the major countries for DEMO as well as achieve the final goal to commercialize fusion energy. In this paper, we apply the TRL and AHP methods in order to identify the key technologies to conduct DEMO R&D. We propose the priorities of future R&D on DEMO by deriving a core technology in the field. At first, we review the scientific theory of fusion and trend of progress of DEMO activities in major countries. For previous studies, we review TRL and AHP methods to examine the technology classification system of DEMO and identify key technologies. We apply TRL method to identify readiness level of DEMO technologies and AHP to compensate shortcoming of TRL. The key technologies of DEMO to be secured from a synthesis result of the TRL and AHP are burning plasma, plasma facing material, structural material, high frequency heating, neutral particle beam, safety, plasma diagnostic, and simulation technologies.

• Food Science and Preservation
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• v.23 no.2
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• pp.275-282
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• 2016

STAR of STAR (SS 01-04) is a series of drinks that consist of various extracts obtained from Coriolus versicolor, Artemisia capillaris Thunb., Hovenia dulcis, Acanthopanax sessiliflorus, Lycium chinense, Citrus reticulata, Saururus chinensis, Pueraria lobata, Pyrus pyrifolia, and Oenanthe javanica. A purpose of this study was to investigate the hepatoprotective effect of SS 01-04. Antioxidant activity of the drinks was evaluated by conducting a hydroxyl radical-scavenging assay. Cytotoxicity and hepatoprotective potential were determined using HepG2 cells in vitro, while protective effects against acute hepatotoxicity was evaluated in vivo. The antioxidant activity of the SS 01-04 at concentration of 100 and 250 mg/mL was similar to that of $50{\mu}M$ vitamin C. tert-Butyl hydroperoxide (tBHP)-induced production of reactive oxygen species (ROS) was blocked by SS 01, 03 and 04 in a dose-dependent manner. Treatment with SS 04 significantly lowered the serum levels of alanine aminotransferase and aspartate aminotransferase in an animal model of carbon tetrachloride $(CCl_4)-induced$ hepatotoxicity (p<0.05). In addition, SS04 increased glutathione level while decreased malondialdehyde level in the liver considerably (p<0.05). It also inhibited the $CCl_4-induced$ increase in the levels of triglyceride and cholesterol in serum and the liver. These findings indicated that SS 01-04 possessed antioxidant activity and protect against ROS. In particular, SS 04 is potentially highly beneficial in treating liver damage as it scavenges reactive free radicals and boosts the endogenous antioxidant system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.107-110
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• 2001

제철소에서 매년 대량 발생되어 주로 매립처분되고 있는 제강분진의 재활용 방안으로서, 폐수처리분야에 널리 사용되고 있는 펜톤산화공정의 반응촉매원인 Fe 공급원으로서 제강분 진의 활용 가능성에 대한 연구를 수행하였다. 본 연구에서는 포항제철소에서 제철부산물로 발생되는 제강분진을 전처리 없이 산화촉매로 사용하여 김포 수도권 매립지의 침출수 처리 공정에서 펜톤산화조에 유입되는 원수를 대상으로 과산화수소에 의한 산화처리 실험을 수행하였다. 반응은 회분식으로 수행하였으며, 일반적으로 알려진 펜톤산화반응의 주요 반응조 건인 운전 pH, 과산화수소 주입량 및 분할주입, 제강분진의 주입량 등의 변화에 따른 각 조 건별 시간에 따른 반응결과를 알아보았다. 또한 기존의 Fe 공급원으로 사용되고 있는 FeSO$_4$와 처리성능 및 적용조건에 대한 비교 실험도 수행하였다. 침출수 수질변화는 TOC (Total Organic Carbon) analyzer를 사용하여 측정한 TOC값으로 나타냈으며, pH controller 와 정량펌프를 사용하여 HCl과 NaOH주입을 통해 반응기간동안 일정 pH를 유지하였다. 본 연구결과, 최적 pH 조건인 4에서 최대 75% TOC 제거율을 나타내었으며, 대부분의 반응은 30분 이내에 이루어졌다. 주어진 실험조건에서 FeSO$_4$와 비교하여 반응속도와 처리효율에서 향상된 결과를 나타내었으며 반응 후 응집침전실험에서도 보다 높은 처리효과를 얻을 수 있었다. 결론적으로, 과산화수소/제강분진 시스템을 이용한 화학적 산화처리방법은 경제성과 처리성능에서 기존의 펜톤산화공정의 대체방안으로서 향 후 적용가능성이 높을 것으로 기대된다.g, 200 mg/kg, 300 mg/kg의 순서로 함량이 점차 감소하는 결과를 얻을 수 있었다. 이상의 결과를 종합하여 볼 때 가자 메탄올추출물은 PQ 유도독성을 신장 및 폐조직에서 효과적으로 경감시키는 것으로 나타났다.ted retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.181-189
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• 2012

We developed a new high-yield synthesis method of free-standing germanium nanocrystals (Ge NCs) by means of the gas-phase photolysis of tetramethyl germanium in a closed reactor using an Nd-YAG pulsed laser. Size control (5-100 nm) can be simply achieved using a quenching gas. The $Ge_{1-x}Si_x$ NCs were synthesized by the photolysis of a tetramethyl silicon gas mixture and their composition was controlled by the partial pressure of precursors. The as-grown NCs are sheathed with thin (1-2 nm) carbon layers, and well dispersed to form a stable colloidal solution. Both Ge NC and Ge-RGO hybrids exhibit excellent cycling performance and high capacity of the lithium ion battery (800 and 1100 mAh/g after 50 cycles, respectively) as promising anode materials for the development of high-performance lithium batteries. This novel synthesis method of Ge NCs is expected to contribute to expand their applications in high-performance energy conversion systems.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.7-14
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• 2015

The aim of this research is suggesting dry processed bottom ash as a new and economical source of lightweight aggregate for mortar and concrete. The dry process of bottom ash is an advance method of water-free and no chloride because only cooled down by double dry conveyer belt systems. Furthermore, because of relatively slow cooling down process helps burning up the remaining carbon in bottom ash. Using this dry process bottom ash, to evaluate the feasibility of using as a lightweight aggregate for mortar and concrete, two-phase of experiments were conducted: 1) improving shape of the bottom ash, and 2) controlling grade of the bottom ash. From the first phase of experiment, additional abrasing process was conducted for round shape bottom ash, hence improved workability and compressive strength was achieved while unit weight was increased comparatively. Based on the better shape of bottom ash, from the second phase, various grades were adopted on cement mortar, standard grade showed the most favorable results on fresh and hardened properties. It is considered that the results of this research contribute on widening sustainable method of using bottom ash based on the dry process and increasing value of bottom ash as a lightweight aggregate for concrete.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.523-530
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• 1999

Acrylic pressure-sensitive adhesive has been made utilizing organic solvents, but nowadays it is made by solvent-free system due to environmental problems. In this study, emulsion polymerization were carried out at $40^{\circ}C$ with methacrylic acid(MAA), n-butyl acrylate(n-BA) and 2-ethylhexyl acrylate(2-EHA) as monomers in the presence of anionic(sodium dodecyl sulfate, SDS) and nonionic(ethylene oxide types) surfactant mixtures. The overall conversion of the polymerization reaction in a mixed surfactant system was found to be higher than that in a single surfactant system. Emulsion stability in mixed or anionic surfactant systems was found to be over 12 week, which was better than that in nonionic surfactant system. Emulsion particle size decreased as surfactant content increased. The Tg and molecular weight of emulsion polymer were inependent of the type, the amount and the mixing ratio of surfactant. Based on the results of stability and peel strength, the optimum nonionic surfactant ratio in total 4 g of surfactant mixture systems is found to be 40~60% by weight where the nonionic surfactant has 50 ethylene oxide groups and 16~18 carbon atoms in hydrophobic alkyl chain.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.11
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• pp.1271-1276
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• 2015

The recent trend is that diesel power generation on islands where its prime cost for power generation is high is replaced by new and renewable energy. Therefore, south Jeolla province is progressing the construction project of self-sufficient islands for the areas where power is supplied by depending on diesel generators, which is the project that power is supplied through eco-friendly energy source using sunlight, wind power and energy storage device etc. However, it is difficult to construct new and renewable energy source with the capacity to respond to the load perfectly due to its environmental and geographical conditions regarding capacity design of new and renewable energy. Besides, Microgrid design considering appropriate capacity design of the system components and efficient operation is required through the analysis of climate conditions and load patterns from the design stage for optimal composition of a hybrid system with economic feasibility. Therefore, this study is aimed to conduct a research on optimal combination, capacity calculation and economic feasibility by comprising a hybrid power generation system which will replace 40% of power generation by diesel as new and renewable energy source for Geomun Island where has more than 300 households and requires expansion of the facility among islands located in southwest coast.

• Journal of the Korean Applied Science and Technology
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• v.7 no.1
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• pp.93-105
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• 1990

Semicarbazone formation of nine monosubstituted benzaldehydes was studied kinetically in 20% methanol buffer solution at 15, 25, 35, and $45^{circ}C$. The rate of p-nitrobenzaldehyde semicarbazone formation is 2.7 times as fast as that of benzaldehyde, while p-hvdroxybenzaldehyde is 3.6 times as slow as that of benzaldehyde. Activation energies for p-chlorobenzaldehyde, benzaldehyde, p-methylbenzaldehyde, p-methoxybenzaldshyde, p-hydroxybenzaldehyde, and p-dimethylaminobenzaldehyde semicarbazone formation are calculated as 5.80, 6.19, 6.57, 7.06, 8.03, and 6.46 kcal/mol respectively. It is concluded from the effect of ionic strength that the reaction is affected by not ions but neutral molecules involving hydrogen bonding between oxygen atom of carbonyl group and hydrogen atom of acid-catalyst, and concerted attack of the necleophilic reagent, free base on carbonyl compound. Also, the effect of solvent composition is small in 20% and 50% methanol (and ethanol) aqueous solutions. The ${\rho}-{\sigma}$ plots for the rates of semicarbazone formation at pH 7.1 show a linear ${\rho}-{\sigma}$ relationship (${\rho}=0.14l$, in contrast to that at pH 2.75 and pH 5.4 corresponding to ${\rho}-{\sigma}$ correlations reparted by Jencks. The rate of semicarbazone formation at pH 5.4 show a relationship which is convex upward, resulting in a break in the curve but at pH 2.75, slight difference from a linear relationship. As a result of studying citric acid catalysis, second-order rate constants increase linearly with citric acid concentration and show a 2 times increase as the catalyst concentration is varied from 0.025 to 0.1 mol/1 at pH 2,9, but slight increase at pH 5.3. The rate-determining step is addition below pH 5 but is dehydration between pH 5 and 7. Conclusively, the rate-determining step of the reaction changes from dehydration to addition in respect to hydrogen ion activity near pH 5. The ortho: para rate ratio of the hydroxybenzaldehydes for semicarbazone formation is about 17 at $15^{\circ}C$. It is concluded that the results constitute strong evidence in favor of greater stabilization of p- than o-hydroxybenzaldehyde by substituent which donate electrons by resonance and is due to hydrogen bonding between the carbon-bound hydrogen of the-CHO group and the oxygen atom of the substituent.

• Environmental and Resource Economics Review
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• v.19 no.1
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• pp.81-100
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• 2010

This paper measures the impacts of the Korea-China Free Trade Agreement (FTA) on the emissions of carbon dioxide ($CO_2$) in Korean export industries. The Korean industrial exports were forecasted by employing Bayesian Kalman Filter Vector Auto-Regression (BVAR) model. The emissions of $CO_2$ were then estimated by applying the $CO_2$ emission coeffcients on the conditionally forecasted values of export by industries. Under the conditional scenario of the 50% reduction in current tariff rate through FTA between Korea and China, the total $CO_2$ emissions in Korea were expected to increase by 1.96% compared to the BAU (Non FT A) trend at the end of 2010. Another conditional scenario with no tariff after 2012 was also adopted. In this case, the total $CO_2$ emlssions were estimated to increase by 2.06% compared to the BAU up until the end of 2014. These facts imply that the FTA between Korea and China would not result in the significant increase of $CO_2$ emissions in Korea.