• 전기화학회지
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• 제13권1호
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• pp.70-74
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• 2010

전기화학 반응을 이용한 실리콘 표면상으로의 단백질 고정을 연구하였다. 이를 위해 Nitrobenzendiazonium(NiBD) 양이온을 화학적 환원반응을 통해 수식하고 수식된 실리콘 표면을 전기화학적으로 다시 환원시켜 나이트로 기능기를 일차아민 기능기로 활성화하여 단백질 고정에 이용하였다. 활성화 된 표면에 금 나노입자를 고정하여 일차 아민 생성을 확인하였다. 또한 이 방법을 응용하여 실리콘 나노선 어레이 중 선택된 나노선 만을 활성화하고 단백질을 선택적으로 고정하는 연구를 수행하였다. 이 연구를 통하여 NiBD 양이온의 화학 및 전기화학 반응이 실리콘 나노선 표면으로 단백질의 선택적 고정화에 유용하게 사용될 수 있음을 보였다.

• 한국정보통신학회논문지
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• 제19권4호
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• pp.848-854
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• 2015

최근 데이터베이스 보안을 위한 다양한 암호화 방법이 제안되고 있다. 이러한 암호화 방법들은 사용자의 민감한 데이터를 효과적으로 보호할 수 있지만 데이터베이스 질의어에 대한 검색 성능이 저하된다. 본 논문에서는 이러한 단점을 보완하기 위하여 블룸필터에서의 선택적 요소 단위의 암호화 방식을 제안하였다. 그리고 다수의 질의어를 통하여 기존에 제안된 튜플 암호화 방식과 성능을 비교하였다. 결과적으로 민감한 정보에 대하여 요소 암호화 방법을 적용하고, 이에 대한 인덱스로서 블룸필터를 사용한 제안 방식이 기존에 제안된 방식보다 검색 시간이 매우 빠르게 나타남을 알 수 있다.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1230-1237
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• 2009

The selective plugging strategy of Microbial Enhanced Oil Recovery (MEOR) involves the use of microbes that grow and produce exopolymeric substances, which block the high permeability zones of an oil reservoir, thus allowing the water to flow through the low permeability zones leading to increase in oil recovery. Bacillus licheniformis TT33, a hot water spring isolate, is facultatively anaerobic, halotolerant, and thermotolerant. It produces EPS as well as biosurfactant and has a biofilm-forming ability. The viscosity of its cell-free supernatant is $120\;mPa{\cdot}s$ at $28^{\circ}C$. Its purified EPS contained 26% carbohydrate and 3% protein. Its biosurfactant reduced the surface tension of water from 72 to 34 mN/m. This strain gave $27.7{\pm}3.5%$ oil recovery in a sand pack column. Environmental scanning electron microscopy analysis showed bacterial growth and biofilm formation in the sand pack. Biochemical tests and Amplified Ribosomal DNA Restriction Analysis confirmed that the oil recovery obtained in the sand pack column was due to Bacillus licheniformis TT33.

• The Korean Journal of Physiology and Pharmacology
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• 제7권2호
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• pp.111-117
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• 2003

Cisplatin is often effective in cancer treatment, but its clinical use is limited because of its nephrotoxicity. We have synthesized new platinum(II) coordination complexes (PC-1 & PC-2) containing trans-${\iota}$ and cis-1,2-diaminocyclohexane (DACH) as carrier ligands and L-3 -phenyllactic acid (PLA) as a leaving group with the aim of reducing nephrotoxicity but maintaining its anticancer activity. In this study, new platinum(II) complex compounds were evaluated for selective cytotoxicity on cancer cell-lines and normal kidney cells. The new platinum complexes have demonstrated high efficacy in the cytotoxicity against human bladder carcinoma cell-lines (T-24/HT-1376). The cytotoxicity of these compounds against rabbit proximal renal tubular cells and human renal cortical tissues, was determined by MTT assay, the [3H]-thymidine uptake and glucose consumption test, and found to be quite less than those of cisplatin. Based on our results, these novel platinum compounds appear to be valuable lead compounds with high efficacy and low nephrotoxicity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.273-275
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• 2005

Active thermography is being used since several years for remote non-destructive testing. It provides thermal images for remote detection and imaging of damages. Also, it is based on propagation and reflection of thermal waves which are launched from the surface into the inspected component by absorption of modulated radiation. For energy deposition, it use external heat sources (e.g., halogen lamp or convective heating) or internal heat generation (e.g., microwaves, eddy current, or elastic wave). Among the external heat sources, the ultrasound is generally used for energy deposition because of defect selective heating up. The heat source generating a thermal wave is provided by the defect itself due to the attenuation of amplitude modulated ultrasound. A defect causes locally enhanced losses and consequently selective heating up. Therefore amplitude modulation of the injected ultrasonic wave turns a defect into a thermal wave transmitter whose signal is detected at the surface by thermal infrared camera. This way ultrasound thermography(UT) allows for selective defect detection which enhances the probability of defect detection in the presence of complicated intact structures. In this paper the applicability of UT for fast defect detection is described. Examples are presented showing the detection of defects in PCB material. Measurements were performed on various kinds of typical defects in PCB materials (both Cu metal and non-metal epoxy). The obtained thermal image reveals area of defect in row of thick epoxy material and PCB.

• 한국연초학회지
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• 제27권2호
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• pp.178-188
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• 2005

To use the filter materials for selective removal of carbonyl compounds in cigarette mainstream smoke, hydrazine such as 2,4-dinitrophenylhydrazine and dansylhydraznie impregnated adsorbents were prepared with perchloric acid or phosphoric acid as a accelerator in hydrazone formation reaction. The change of morphology of adsorbents in various of impregnator were investigated by SEM. Impregnation amount caused by reaction time, acid type and impregnation reagent, and the adsorption properties of carbonyl compounds in cigarette mainstream smoke were investigated. Amounts of impregnation was increased as increasing reaction time. The removal amount for vapor phase carbonyl compounds by 2,4-DNPH impregnated adsorbent was higher than that of dansylhydrazine impregnated adsorbent. The selectivity of 2,4-DNPH impregnated polyacrylic type adsorbent was superior to those of other adsorbents. This results indicated that the 2,4-DNPH impregnated polyacrylic adsorbent was applicable to cigarette filter material because of its fast reactivity and porosity.

• Toxicological Research
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• 제27권2호
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• pp.85-93
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• 2011

Selective estrogen receptor modulators (SERMs) are synthetic molecules which bind to estrogen receptors (ER) and can modulate its transcriptional capabilities in different ways in diverse estrogen target tissues. Tamoxifen, the prototypical SERM, is extensively used for targeted therapy of ER positive breast cancers. Unfortunately, the use of tamoxifen is associated with acquired resistance and some undesirable side effects. This study investigated the availability of the conventional SERMs on the TAM-resistance breast cancer cells. SERMs showed more effectiveness in MCF-7 cells than tamoxifen resistant cells, except toremifene and ospemifene. Especially, toremifene was more efficacious in tamoxifen resistant cells than MCF-7. Ospemifene had similar cytotoxic activity on the two types of breast cancers. The other SERMs used in this experiment didn't inhibit efficiently the proliferation of tamoxifen resistant cells. These results support the possibility to usage of toremifene on tamoxifen resistant cancer. The effectiveness by toremifene on tamoxifen resistant cells might be different pathways from the apoptosis and the autophagy. Further study should be needed to elucidate the underlying mechanism of effect of toremifene on tamoxifen resistant cancer.

• 디지털융복합연구
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• 제11권10호
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• pp.453-458
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• 2013

HMM 음성 인식 시스템은 환경적 잡음과 여러 음성의 혼합으로 인하여 정확한 음성을 인지하지 못하는 단점이 있다. 따라서 본 논문은 잡음 음성으로 부터 원하는 음성만 선택하여 추출하기 위한 음성 특징 추출 기법을 CHMM을 이용하여 제안한다. 선택적 음성 추출을 위한 채널 유사성 상관 관계를 이용하여 음성 특징을 추출하는 방법을 사용하였다. 제안 기법의 실험 평가한 결과 평균 분리 왜곡도가 0.430dB 감소됨을 보임으로써 제안한 방법의 우수성을 확인하였다.

• 대한금속재료학회지
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• 제50권3호
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• pp.191-200
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• 2012

The purpose of this paper is to review the state of laser processing technology using metal powders. In recent years, a series of research and development efforts have been undertaken worldwide to develop laser processing technologies to fabricate metal-based parts. Layered manufacturing by the laser melting process is gaining ground for use in manufacturing rapid prototypes (RP), tools (RT) and functional end products. Selective laser sintering / melting (SLS/SLM) is one of the most rapidly growing rapid prototyping techniques. This is mainly due to the processes's suitability for almost any materials, including polymers, metals, ceramics and many types of composites. The interaction between the laser beam and the powder material used in the laser melting process is one of the dominant phenomena defining feasibility and quality. In the case of SLS, the powder is not fully melted during laser scanning, therefore the SLS-processed parts are not fully dense and have relatively low strength. To overcome this disadvantage, SLM and laser cladding (LC) processes have been used to enable full melting of the powder. Further studies on the laser processing technology will be continued due to the many potential applications that the technology offers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권4호
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• pp.1193-1215
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• 2021

The measurement of the key product quality index plays an important role in improving the production efficiency and ensuring the safety of the enterprise. Since the actual working conditions and parameters will inevitably change to some extent with time, such as drift of working point, wear of equipment and temperature change, etc., these will lead to the degradation of the quality variable prediction model. To deal with this problem, the selective integrated moving windows based principal component regression (SIMV-PCR) is proposed in this study. In the algorithm of traditional moving window, only the latest local process information is used, and the global process information will not be enough. In order to make full use of the process information contained in the past windows, a set of local models with differences are selected through hypothesis testing theory. The significance levels of both T - test and χ² - test are used to judge whether there is identity between two local models. Then the models are integrated by Bayesian quality estimation to improve the accuracy of quality variable prediction. The effectiveness of the proposed adaptive soft measurement method is verified by a numerical example and a practical industrial process.