• 마이크로전자및패키징학회지
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• 제21권3호
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• pp.25-29
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• 2014

본 연구에서는 친환경적이고, 보관수명이 1년 이상이며, 부식특성이 좋은 플라즈마 유기막 표면처리에 대한 솔더링 특성을 기존 표면처리법인 OSP와 비교하였다. 플라즈마 표면처리는 할로겐계 전구체를 사용하여 CVD 방법으로 증착하였고, 증착두께는 20 nm이었다. 본 연구에서 사용된 솔더 조성은 Sn-3.0 wt%Ag-0.5 wt%Cu이었다. 염수분무시험에서 플라즈마 표면처리 유기막은 OSP보다 우수한 부식 저항성을 나타내었다. 멀티리플로우 조건에서 플라즈마 표면처리는 OSP보다 우수한 솔더 퍼짐성을 나타내었다. 솔더링 후 단면 미세조직을 분석한 결과, 플라즈마 표면처리와 OSP시편 모두 유사한 금속간화합물층 두께 및 형상을 갖고 있었다. 플라즈마 표면처리와 OSP 모두 유사한 접합강도를 가지고 있었다.

• 한국입자에어로졸학회지
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• 제15권4호
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• pp.191-202
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• 2019

In this study, performance (particle removal efficiency and breathing resistance) of several commercially available face masks (electrostatic filter masks (KF80 certified), a nanofiber filter mask (KF80 certified), and an uncertified mask) with their filter structure and composition were evaluated. Also, effects of relative humidity (RH) of incoming air, water and alcohol exposure, and reusability on performance of face masks were examined. Monodisperse and polydisperse sodium chloride particles were used as test aerosols. Except the uncertified mask filter, PM_2.5 removal efficiency was found to be higher than 90%, and the nanofiber filter mask had the highest quality factor due to the low pressure drop and high removal efficiency (nanofibers were arranged in a densely packed pore structure and contained a significant amount of fluorine in addition to carbon and oxygen). In the case of the KF80 certified mask, the removal efficiency was little affected when the RH of incoming air increased. When the mask filters were soaked in water, the removal efficiency of mask filters was degraded. In particular, the uncertified mask filter showed the highest removal efficiency degradation (26%). When the mask was soaked in alcohol, the removal efficiency also decreased with the greater degree than the water soaking case. The nanofiber mask filter showed the strongest resistance to alcohol exposure among tested mask filters. During evaluation of reusability of masks in real life, the removal efficiency of certified mask filter was less than 4% for 5 consecutive days (2 hours per day), while the removal efficiency of uncertified mask filter significantly decreased by 30% after 5 days.

• Asian Pacific Journal of Cancer Prevention
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• 제16권1호
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• pp.387-391
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• 2015

Background: Fluorine-18 deoxyglucose positron emission tomography computed tomography (18F-FDG-PET/CT) and bone scintigraphy (BS) are widely used for the detection of bone involvement. The optimal imaging modality for the detection of bone metastases in hormone receptor positive (+) and negative (-) groups of breast cancer remains ambiguous. Materials and Methods: Sixty-two patients with breast cancer, who had undergone both 18F-FDG-PET/CT and BS, being eventually diagnosed as having bone metastases, were enrolled in this study. Results: 18F-FDG-PET/CT had higher sensitivity and specificity than BS. Our data showed that 18F-FDGPET/CT had a sensitivity of 93.4% and a specificity of 99.4%, whiel for BS they were 84.5%, and 89.6% in the diagnosis of bone metastases. ${\kappa}$ statistics were calculated for 18F-FDGPET/CT and BS. The ${\kappa}$-value was 0.65 between 18F-FDG-PET/CT and BS in all patients. On the other hand, the ${\kappa}$-values were 0.70 in the hormone receptor (+) group, and 0.51 in hormone receptor (-) group. The ${\kappa}$-values suggested excellent agreement between all patient and hormone receptor (+) groups, while the ${\kappa}$-values suggested good agreement in the hormone receptor (-) group. Conclusions: The sensitivity and specificity for 18F-FDG-PET/CT were higher than BS in the screening of metastatic bone lesions in all patients. Similarly 18F-FDG-PET/CT had higher sensitivity and specificity in hormone receptor (+) and (-) groups.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3525-3531
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• 2014

Objective: Fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is a new technique for identifying different malignant tumors using different uptake values between tumor cells and normal tissues. Here we assessed the diagnostic accuracy of 18F-FDG-PET in patients with testicular cancer by pooling data of existing trials in a meta-analysis. Methods: PubMed/MEDLINE, Embase and Cochrane Central Trials databases were searched and studies published in English relating to the diagnostic value of FDG-PET for testicular cancer were collected. The summary receiver operating characteristic (SROC) curve was used to examine the FDG-PET accuracy. Results: A total of 16 studies which included 957 examinations in 807 patients (median age, 31.1 years) were analyzed. A meta-analysis was performed to combine the sensitivity and specificity and their 95% confidence intervals (CIs), from diagnostic odds ratio (DOR), positive likelihood ratios (PLR), negative likelihood ratio (NLR). SROC were derived to demonstrate the diagnostic accuracy of FDG-PET for testicular cancer. The pooled sensitivity and specificity were 0.75 (95% confidence interval (CI), 0.70-0.80) and 0.87 (95% CI, 0.84-0.89), respectively. The pooled DOR was 35.6 (95% CI, 12.9-98.3). The area under the curve (AUC) was 0.88. The pooled PLR and pooled NLR were 7.80 (95% CI, 3.73-16.3) and 0.31 (95% CI, 0.23-0.43), respectively. Conclusion: In patients with testicular cancer, 18F-FDG-PET demonstrated a high SROC area, and could be a potentially useful tool if combined with other imaging methods such as MRI and CT. Nevertheless, the literature focusing on the use of 18F-FDG-PET in this setting still remains limited.

• 한국진공학회지
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• 제17권2호
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• pp.90-95
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• 2008

본 연구에서는 열 및 불산을 이용한 후처리 공정이 레지스트층을 이용하여 제작된 탄소나노튜브의 전자 방출 특성에 미치는 영향에 대하여 연구하였다. 전자 방출 전류는 초기에 $8V/{\mu}m$의 전계에서 $4.2{\mu}A/cm^2$의 전류에서 열 및 불산 처리 시 각각 $7.5mA/cm^2$ 및 $79mA/cm^2$로 향상되었다. 하지만 열 및 불산 처리를 동시에 실시한 경우 전류 밀도는 $426mA/cm^2$ 및 $656mA/cm^2$로 향상된 전자 방출 특성을 얻을 수 있었다. 전자 방출 특성은 처리 순서에 따라 증가하는 양이 다르게 나타났으며, 가장 우수한 전자 방출 특성은 열 처리를 먼저 시행 후, 불산 처리를 하는 공정에서 나타났다. 이는 열 처리에 의한 탄소나노튜브의 결정성의 증가와 이후 불산 처리에 의한 불소 결합의 증가에 기인함을 알 수 있었다. 강한 불소 결합은 탄소나노튜브 에미터의 전자 방출 특성의 향상에 크게 기여를 하였다.

• 한국치위생학회지
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• 제9권3호
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• pp.344-356
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• 2009

To identify subjective health status of senior citizens' oral health following senior citizens' general characteristics and knowledge and behavior for the oral hygiene, this research conducted individual interview with 237 senior citizens in some parts of Seoul. The results are as follows. 1. Degree of senior citizens' knowledge on the oral hygiene is about Middle. Among the categories on the senior citizens' knowledge on the oral hygiene, teeth's brushing was the highest while knowledge on fluorine was the lowest. 2. Senior citizens who feel that their oral health is healthy when it comes to the subjective health state of senior citizens' oral health following behavior for the oral hygiene, brush their teeth, three times in a day, for more than three minutes (p<.01). Moreover, senior citizens who feel that their oral health is healthy brush different corners of the tongue when brushing (p<.01). 3. In case of knowledge on the oral hygiene following general characteristics, knowledge on the oral hygiene was higher when economic status was higher (p<.01). In case of living expenses, knowledge on the oral hygiene was higher for the senior citizens with pay or income (p<.01). 4. In case of behavior for the oral hygiene, women tended to act for the oral hygiene more than men. As for the method for raising living expenses, senior citizens who receive basic social security check or those at the highest tier tended to act less for the oral hygiene (p<.01). 5. Senior citizens who answered that their oral health is healthy when it comes to the subjective health state of senior citizens' oral cavity tended to have high knowledge on the oral hygiene (p<.01). In conclusion, subjective health status of senior citizens' oral health is higher when the knowledge on the oral hygiene and behavior for the oral hygiene are higher. Accordingly, it is necessary to develop and execute oral hygiene training program to change senior citizens' behavior incrementally and the dental hygienists who can conduct this training should be actively attracted into the senior citizens' oral hygiene training.

• 농약과학회지
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• 제13권2호
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• pp.63-69
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• 2009

벼 도열병균에 대하여 2-페닐이미노-1,3-티아졸린-4-아세트아닐리드 유도체의 NH수소가 항균력에 미치는 영향을 조사하기 위하여 2-페닐이미노-1,3-티아졸린 골격의 C-4 곁가지에 모르포리닐, 피페리디닐 등의 기능기가 도입된 4-모르포리 닐카르보닐메틸-2-페닐이미노-1,3-티아졸린 2(X=O), 피페리디닐카르보닐메틸-2-페닐이미노-1,3-티아졸린 3(X=C) 등의 새로운 화합물을 합성하였다. 합성된 30종 화합물의 대표적인 식물병원균 6종에 대한 항균력 시험을 수행하였다. 키틴 이합체를 염소로 처리한 다음 생성된 중간체, 아세토아세틸클로라이드의 분리없이 모르폴린 또는 피페리딘과 반응시켜 각각 상응하는 감마-클로로-베타-케토 유도체를 얻었다. 이들을 각각 티오우레아 유도체와 반응시켜 4-모르포리닐카르보닐메틸-2-페닐이미노-1,3-티아졸린 2, 피페리디닐카르보닐메틸-2-페닐이미노-1,3-티아졸린 3을 좋은 수율(27-98%)로 합성하였다. 화합물 3의 벼 도열병원균에 대한 항균력은 피페리디닐기가 C-4 위치에 치환되어 있고 2-페닐이미노기의 페닐기의 ortho 및 para 위치에 불소가 포함된 화합물의 경우(3j)에 가장 높았다 (100 ppm, 90%). 이것으로 미루어보아 2-페닐이미노-1,3-티아졸린 계열의 C-4위치의 치환체는 이 계열 화합물의 벼도열병균에 대한 항균활성을 나타내는데 보조적인 역할을 하는 것으로 생각된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.77-77
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• 1998

Present silicon dioxide (SiOz) 떠m as intennetal dielectridIMD) layers will result in high parasitic c capacitance and crosstalk interference in 비gh density devices. Low dielectric materials such as f f1uorina뼈 silicon oxide(SiOF) and f1uoropolymer IMD layers have been tried to s이ve this problem. I In the SiOF ftlm, as fluorine concentration increases the dielectric constant of t뼈 film decreases but i it becomes unstable and wa않r absorptivity increases. The dielectric constant above 3.0 is obtain어 i in these ftlms. Fluoropolymers such as polyte$\sigma$따luoroethylene(PTFE) are known as low dielectric c constant (>2.0) materials. However, their $\alpha$)Or thermal stability and low adhesive fa$\pi$e have h hindered 야1리ru뚱 as IMD ma따"ials. 1 The concept of a plasma processing a찌Jaratus with 비gh density plasma at low pressure has r received much attention for deposition because films made in these plasma reactors have many a advantages such as go여 film quality and gap filling profile. High ion flux with low ion energy in m the high density plasma make the low contamination and go어 $\sigma$'Oss피lked ftlm. Especially the h helicon plasma reactor have attractive features for ftlm deposition 야~au똥 of i앙 high density plasma p production compared with other conventional type plasma soun:es. I In this pa야Jr, we present the results on the low dielectric constant fluorocarbonated-SiOF film d밑JOsited on p-Si(loo) 5 inch silicon substrates with 00% of 0dFTES gas mixture and 20% of Ar g gas in a helicon plasma reactor. High density 띠asma is generated in the conventional helicon p plasma soun:e with Nagoya type ill antenna, 5-15 MHz and 1 kW RF power, 700 Gauss of m magnetic field, and 1.5 mTorr of pressure. The electron density and temperature of the 0dFTES d discharge are measUI벼 by Langmuir probe. The relative density of radicals are measured by optic허 e emission spe따'Oscopy(OES). Chemical bonding structure 3I피 atomic concentration 따'C characterized u using fourier transform infrared(FTIR) s야3띠"Oscopy and X -ray photonelectron spl:’따'Oscopy (XPS). D Dielectric constant is measured using a metal insulator semiconductor (MIS;AVO.4 $\mu$ m thick f fIlmlp-SD s$\sigma$ucture. A chemical stoichiome$\sigma$y of 야Ie fluorocarbina$textsc{k}$영-SiOF film 따~si야영 at room temperature, which t the flow rate of Oz and FTES gas is Isccm and 6sccm, res야~tvely, is form려 야Ie SiouFo.36Co.14. A d dielec$\sigma$ic constant of this fIlm is 2.8, but the s$\alpha$'!Cimen at annealed 5OOt: is obtain려 3.24, and the s stepcoverage in the 0.4 $\mu$ m and 0.5 $\mu$ m pattern 킹'C above 92% and 91% without void, res야~tively. res야~tively.

• 핵의학기술
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• 제15권1호
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• pp.86-89
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• 2011

최근 들어 양전자방출단층촬영(positron emission tomography, PET) 대표적인 진단검사인 FDG (2-[$^{18}F$]fluoro-2-deoxy-D-glucose)를 이용한 전신암 및 장기별 대사 검사뿐만 아니라 또 다른 양전자 방출 동위원소 탄소-11로 표지 된 다양한 방사성의약품 사용이 증가될 예정이다. 본 논문에서는 현재 국내에 설치 보급되어있는 국산 KOTRON-13 사이클로트론에 냉각 성능이 개선된 탄소-11 표적 장치를 설계, 제작하고, 다양한 생산시험을 통하여 탄소-11의 생산량 증대를 입증 하였다. 성공적으로 기존의 불소-18 타겟과 새로운 탄소-11 타겟 호환장치를 도입하였고, 실험 결과 고효율 탄소-11표적 장치가 내수성이 우수하고, 30분 조사 시 최대 2,000 mCi를 생산하였다. 본 시험결과를 통해 향후 불소-18만이 생산 가능했던 국산 KOTRON-13 사이클로트론에 효율적이고 안정적으로 탄소-11생산 시스템을 도입할 수 있음을 증빙하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.259-259
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• 2011

염료감응형 태양전지(Dye-Sensitized Solar Cells:DSSC)는 환경 친화적이며, 저가의 공정에 대한 가능성으로 기존의 고가의 결정질 실리콘 태양전지의 경제적인 대안으로 각광을 받고 있다. 최근 염료감응형 태양전지는 투명 전도성 산화막(Transparent Conducting Oxide : TCO)으로 사용되는 Fluorine Tin Oxide (FTO)가 증착된 유리기판 위에 주로 제작된다. FTO는 낮은 비저항과 가시광선 영역에서 높은 투과도를 가지는 우수한 전기-광학적 특성을 갖지만, 비교적 공정이 까다로운 Chemical Vapor Deposition (CVD)법으로 제조하며, 전체 공정비용의 60%를 차지하는 높은 생산단가로 인해 현재 FTO를 대체할 재료개발 연구가 활발히 진행되고 있다. 그 중 ZnO (Zinc Oxide)는 우수한 전기-광학적 특성과 비교적 저렴한 가격으로 새로운 TCO로써 주목받고 있다. ZnO는 넓은 energy band gap (3.4 [eV])의 육방정계 울자이트(hexagonal wurtzite) 결정 구조를 가지는II-VI족 n형 반도체 물질이며, III족 금속원소인 Al, Ga 및 In 등의 불순물을 첨가하면 TCO로서 우수한 전기-광학적 특성과 안정성을 나타낸다. 이들 물질중 $Zn^{2+}$ (0.060 nm)의 이온반경과 유사한 $Ga^{2+}$0.062 nm) 이온이 ZnO의 격자반경을 최소화 시킬 수 있다는 장점으로 최근 주목 받고 있다. 하지만 Ga-doped ZnO (GZO)의 경우 DSC에 사용되는 루테늄 계열의 산성 염료 하에 장시간 두면 표면이 파괴되는 문제가 발생하며, $TiO_2$ paste를 Printing 후 열처리하는 과정에서도 박막의 파괴가 발생할 수 있다. 이를 방지하기 위해 $TiO_2$ Blocking Layer를 GZO 투명전극 위에 증착하였다. 또한, $TiO_2$ Blocking Layer를 적용한 GZO 박막을 전면전극으로 이용하여 DSC를 제작하여 효율을 확인하였다. 2wt%의 $Ga_2O_3$가 도핑된 ZnO 박막은 20mTorr 400$^{\circ}C$에서 Pulsed Laser Deposition (PLD)에 의해 성장되었고, $TiO_2$박막은 Ti 금속을 타겟으로 이용하여 30mTorr 400$^{\circ}C$에서 증착되었다. Scanning electron microscopy (FE-SEM)을 이용한 박막 분석 결과 $TiO_2$가 증착된 GZO 박막의 경우 표면 파괴가 일어나지 않았다. Solar Simulator을 이용하여 I-V특성 측정결과 상용 FTO를 사용한 DSC 수준의 효율을 나타내었다. 이에 따라 Pulsed Laser Deposition을 이용해 제작된 GZO 기판은 $TiO_2$ Blocking Layer를 이용하여 표면 파괴를 방지할 수 있었으며, 이는 향후 염료감응형 태양전지의 투명전극에 적용 가능 할 것으로 판단된다.