• Journal of Dental Anesthesia and Pain Medicine
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• 제22권2호
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• pp.129-143
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• 2022

Background: Patient-controlled analgesia (PCA) has been widely used as an effective medical treatment for pain and for postoperative analgesia. However, improper dose errors in intravenous (IV) administration of narcotic analgesics from a PCA infusion pump can cause patient harm. Furthermore, opioid overdose is considered one of the highest risk factors for patients receiving pain medications. Therefore, accurate delivery of opioid analgesics is a critical function of PCA infusion pumps. Methods: We designed a microbalance method that consisted of a closed acrylic chamber containing a layer and an oil layer with an electronic balance. A commercially available infusion analyzer (IDA-5, Fluke Co., Everett, WA, USA) was used to measure the accuracy of the infusion flow rate from a commercially available smart PCA infusion pump (PS-1000, UNIMEDICS, Co., Ltd., Seoul, Korea) and compared with the results of the microbalance method. We evaluated the uncertainty of the flow rate measurement using the ISO guide (GUM:1995 part3). The battery life, delay time of the occlusion alarm, and bolus function of the PCA pump were also tested. Results: The microbalance method was good in the short-term 2 h measurement, and IDA-5 was good in the long-term 24 h measurement. The two measurement systems can complement each other in the case of the measurement time. Regarding battery performance, PS-1000 lasted approximately 5 days in a 1 ml/hr flow rate condition without recharging the battery. The occlusion pressure alarm delays of PS-1000 satisfied the conventional alarm threshold of occlusion pressure (300-800 mmHg). Average accuracy bolus volume was measured as 63%, 95%, and 98.5% with 0.1 ml, 1 ml, and 2 ml bolus volume presets, respectively. A 1 ml/hr flow rate measurement was evaluated as 2.08% of expanded uncertainty, with a 95% confidence level. Conclusion: PS-1000 showed a flow accuracy to be within the infusion pump standard, which is ± 5% of flow accuracy. Occlusion alarm of PS-1000 was quickly transmitted, resulting in better safety for patients receiving IV infusion of opioids. PS-1000 is sufficient for a portable smart PCA infusion pump.

• 한국자기학회지
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• 제9권6호
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• pp.271-277
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• 1999

M ssbauer 분광법을 이용하여 비정질합금 Fe83B9Nb7Cu1의 자기적 성질을 연구하였다. 개선된 Vincze의 방법을 적용하여 각 온도에서 초미세자기장, 이성질체 이동치, 그리고 quadrupole line broadening의 분포함수들을 얻었고 큐리온도는 393K, Hhf(0)는 231kOe로 산출되었다. 환산된 평균 초미세 자기장(reduced average hyperfine field)의 온도 변화는 S=1 자기화 곡선에 비해 급히 감소하는 양상을 보였고 이를 설명하기 위해 Handrich의 분자장 이론에서 교환 상호 작용의 척도인 에 =0.75-0.64(T/Tc)+0.47(T/Tc)2의 온도 의존성을 도입하였다. 평균 초미세 자기장(Hhf(T))은 저온에서 스핀파 여기에 의한 공식 Hhf(T)=Hhf(0)[1-0.44(T/Tc)3/2-0.28(T/Tc)5/2- ]으로 분석하였고, 큐리온도 부근에서는 1.00[1-T/Tc]0.39의 관계를 갖는 것으로 나타났다. 초미세 자기장 분포곡선의 선폭은 13K에서 102kOe (3.29 mm/s)였으며, 오도가 증가함에 따라 감소했다. 큐리온도 이상에서 평균 quadrupole splitting값은 0.43 mm/s였으며 quadrupole 이동치 분포에 의한 선폭 증가는 13K에서 0.1 mm/s, 320K에서는 0.072 mm/s 정도로 초미세 자기장 분포나 quadrupole line broadening에 의한 선폭 증가보다 작았다. 이성질체 이동치의 온도 변화에 Debye 모형을 적용하여 Debye 온도를 D=424K로 산출하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.198.2-198.2
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• 2016

Reactive oxygen and nitrogen species (RONS) can be generated by using non-thermal atmospheric pressure plasma jet which have profound biomedical applications [1, 2]. In this work, reactive oxygen species like hydroxyl radical (OH) are generated by using non-thermal direct plasma jet above water surface using Ar gas and their properties have been studied using ultraviolet absorption spectroscopy. OH radicals are found to be generated simultaneously with the discharge current with concentration of $2.7{\times}1015/cm3$ at 7mm above water surface while their persistence time have been measured to be $2.8{\mu}S$. In addition, it has been shown that plasma initiated ultraviolets play a major role to generate RONS inside water. Further works are going on to measure the temporal behavior of OH and $O2^*-$.

• 음성과학
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• 제13권4호
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• pp.7-21
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• 2006

The intent of the present study is to investigate the acoustic properties of Korean /w/ in various phonological contexts, compare them with those of English /w/, and attempt to explain why English /w/'s are perceived differently by Korean speakers depending on the phonological contexts. Experiments 1 and 2 present the acoustic measure of F2 of Korean /w/ in various linguistic positions and show that unlike English /w/, Korean /w/ shows quite a strong coarticulation with the following vowel. Based on these experiments, Experiment 3 investigates why English /w/ is adapted differently into Korean. Specifically, it discusses why English /wain/ is adapted as /wain/ whereas English /twin/ is adapted into Korean as $/t^{h_i}win/$ with an extra vowel. This study argues that the different perception of English /w/ by Korean and English speakers is due to the different F2 transitional pattern of /w/ in Korean and English in various phonological contexts. It also argues that the F2 transitional pattern is an important factor in the perception of /w/.

• Nuclear Medicine and Molecular Imaging
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• 제43권4호
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• pp.337-343
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• 2009

목적: (R)-1-(2-Chlorophenyl)-N-methyl-N-1-(1-methyl-propyl)-3-isoquinoline carboxamide ((R)-PK11195)는 말초형 벤조디아제핀 수용체 (PBR)의 친화성이 높으며, 활성화된 소교세포(microglia)의 PBR에 선택적으로 결합하는 것으로 알려져 있다. 본 연구에서는 말초형 벤조디아제핀 수용체 (PBR)의 FET용 리간드인[$^{11}$C](R)-PK11195를, 절차가 빠르고 간단한 [$^{11}$C]CH$_3$I 자동합성장치 및 루프법을 도입해서 합성하였다. 대상 및 방법: 사이클로트론에서 $^{14}$N(p,a)$^{11}$C핵반응에 의하여 생산된 [$^{11}$C]Co$_2$를 0.2 M LiAlH$_4$/THF (0.2 mL)로 환원한 다음 HI (1 mL)과 반응하여 [$^{11}$C]CH$_3$I를 생산하였다. 반응용매인 NaH DMF complex (0.1 mL)와 녹인 전구물질 (R)-N-desmethyl-PK11195 (1 mg)을 녹인 DMSO (0.1mL)를 섞은 혼합액을 HPLC의 루프에 미리 주입하고 [$^{11}$C]CH$_3$I를 상온에서 5분 동안 질소가스로 불어준 뒤에 semi-preparative HPLC로 [$^{11}$C](R)-PK11195를 분리하였다. 결과: 전구물질과 [$^{11}$C]CH$_3$I의 [$^{11}$C]메틸화 반응에서의 표지효율은 71.8$\pm$8.5% 이었다. 분리 후 얻은 [$^{11}$C](R)-PK11195의 비방사능은 11.8$\pm$6.4 GBq/$\mu$mol이었으며, 방사화학적 순도는 99.2% 이상이었다. C-11 표지 후 얻어진 (R)-PK11195의 물질의 질량 분석은 m/z 353.1 (M+1)으로 물질구조를 확인 할 수 이었다. 결론: 뇌염증에 의한 활성화 소교세포의 영상화를 위한 PET용 방사성의약품인 [$^{11}$C](R)-PK11195를 반복적으로 생산해야 하는 임상 적용을 위해, 합성절차가 빠르고 간단한 [$^{11}$C]CH$_3$I 자동화 합성장치를 1차 루프 방법을 이용하여 $^{11}$C을 표지 할 수 있었다. 이 연구를 통해서 [$^{11}$C](R)PK11195 표지 할 때 반응 단계를 줄이고 반응을 실온에서 할 수 있어서 표지과정을 보다 단순화할 수 있었으며, NaH의 DMF현탁액을 사용함으로써 보다 안전하게 생산할 수 있게 되었다.

• Journal of Magnetics
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• 제13권1호
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• pp.34-36
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• 2008

For the measurement of the magnetic field distribution with high spatial resolution and high accuracy, the magnetic field sensing probe must be non-magnetic, but the MFM probe and sub-millimeter-meter size Hall probe use a ferromagnetic tip and block, respectively, to increase the sensitivity. To overcome this drawback, we developed a micro-size search coil magnetometer which consists of a single turn search coil, Terfenol-D actuator, scanning system, and control software. To reduce the noise generated by the stray ac magnetic field of the actuator driving coil, we employed an even function $\lambda$-H magnetostriction curve and lock-in technique. Using the developed magnetometer, we were able to measure the magnetic field distribution with a magnetic field resolution of 1 mT and spatial resolution of $0.1mm{\times}0.2mm$ at a coil vibration frequency of 1.8 kHz.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.147-150
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• 2003

Water toxicity monitoring based on the continuous cultivation of Photobacterium phorphoreum is presented. Normally, after 10 days of operation, a dark variant, which emits no light, appears and dominates the population, resulting in a rapid decrease in bioluminescence. Therefore, to overcome this problem, a fluidized-bed reactor is used in which alginate-immobilized cells are grown and leaking cells are continuously released into the effluent Experimental results revealed that the dominance of dark variants was suppressed inside the immobilized beads, thereby mitigating the rapid loss of bioluminescence. Plus, a high dilution rate (1.2 h$\^$-1/) prevented the occurrence of other microbial contamination in the reactor The concentration and bioluminescence of the released cells were sufficient to measure the water toxicity for more than 4 weeks.

• 한국분무공학회지
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• 제1권1호
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• pp.28-34
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• 1996

Study on the mechanism of droplet transport and the droplet eddy diffusivity in the intake manifold of internal conbustion engine with carburetor has been carried out in this paper The theory and experiments were studied and performed respectively, to elucidate the mechanism and to measure typical rates of deposition, on the walls of a straight type intake manifold, of water droplets suspended in a turbulent air streams. Accordingly, the results are that Mechanism of a spray transport to the walls is caused by the fluctuation component of radial velocity. Deposition rate of a spray on the walls is mainly dependent upon air velocity and mean diameter of spray, and Droplet eddy diffusivity in the intake manifold is around $80\sim105cm^2/sec$.

• 한국자원식물학회지
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• 제28권3호
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• pp.305-311
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• 2015

This study investigated in vitro antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells of different solvent extracts from Jerusalem artichoke (Helianthus tuberosus L.) tuber. The EtOH extract contained amounts of phenolics (22.20 tannic acid equivalent ㎎/ɡ) and exhibited the highest antioxidant activity and anti-inflammatory activity. Several methods were employed for measure the antioxidant activity: 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (IC₅₀ = 206.79 ㎍/㎖), reducing power activity (21.26 ascorbic acid equivalent ㎎/ɡ) and total antioxidant activity (19.05 ascorbic acid equivalent ㎎/ɡ). Meantime, the EtOH extract inhibited the NO production completely with a concentration of 800 ㎍/㎖. Besides, the H₂O extract exhibited more potent effect on human lung epithelial A549 cells. This study suggested that Jerusalem artichoke tuber had antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells.

• 지질공학
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• 제20권2호
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• pp.213-220
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• 2010

현재 국내의 수리시험 장비는 적절한 장비가 갖추어지지 않은 상태로 시행되고 있기 때문에 투수성 해석 자료의 신뢰성은 그리 높다고 볼 수 없다. 본 연구는 고도의 정밀성을 요구하는 고준위폐기물의 처분기술 개발을 위해서는 무엇보다도 자연방벽에 대한 특성 평가가 중요하므로 현행 시험 장비의 기술적 문제들을 해결하기 위한 목적으로 장심도 (1,000 m) 시추공에서 정밀한 수리시험이 가능한 장비를 성공적으로 구축하였다. 본 장비에서 가장 중요하게 반영된 기술사항은 공내 저류효과를 최소화시키기 위하여 H-DHSIV를 장착하고, 시험 자료의 품질을 향상시키기 위하여 실시간으로 시험 구간을 포함한 3개 구간의 압력 변화자료를 취득할 수 있는 DAS를 구축한 것이다. 본 연구의 결과로 구축된 심부 시추공에서의 정밀 수리 시험 장비는 국내 현장조사 기술력의 획기적인 향상을 선도할 것이며, 방사성폐기물 처분기술 개발을 위한 연구와 부지 특성평가에 직접 적용될 것이다.