• 전기전자학회논문지
• /
• 제27권1호
• /
• pp.122-126
• /
• 2023

본 논문에서는 복합 미생물 배양기의 제어시스템을 제안하였다. 제안하는 제어시스템은 복합 미생물 배양기의 제어부, 통신부, 전원부, 제어시스템 등으로 구성된다. 복합 미생물 배양기의 제어부는 아날로그 신호와 디지털 신호의 변환, LCD 패널을 이용한 디스플레이, 수위센서, 온도센서, pH 농도센서 등과 같은 센서들의 신호 제어를 하도록 설계 및 제작한다. 사용하는 수위센서는 기존 수위센서가 거품과 같은 이물질 등으로 인해 측정이 어려운 문제점을 해결하고자 직진성이 우수한 IR 레이저 방식을 사용하여 정확한 수위 측정이 가능하도록 설계 및 제작한다. 온도센서는 열 저항 원리를 사용하여 측정함으로써, 높은 정확도와 누적 저항 오차가 없도록 설계하여 사용한다. 통신부는 2개의 LAN 포트와 1개의 RS-232 포트로 구성하여 복합 미생물 배양기에서 사용되는 LCD 패널, PCT 패널, 로드셀 컨트롤러 등의 신호를 제어부에 전달할 수 있도록 설계 및 제작한다. 전원부는 제어부와 통신부가 원활하게 동작할 수 있도록 24V, 12V 5V 등 3개의 전압 공급 단자로 구성하여 전원을 공급하도록 설계 및 제작한다. 복합 미생물 배양기의 제어시스템은 PLC를 사용하여 pH 농도센서, 온도센서, 수위센서 등의 센서값과 배양에 사용되는 써큘레이션 펌프, 써큘레이션 밸브, 로터리 펌프와 인버터 로드셀 등의 동작을 제어한다. 제안된 복합 미생물 배양기의 제어시스템의 성능을 평가하기 위하여 공인인증기관에서 실험한 결과는 수위 측정감도의 범위가 -0.41mm~1.59mm로, 물 온도의 변화 폭이 ±0.41℃로 현재 상용으로 판매되는 제품들 성능보다 우수한 성능으로 동작됨이 확인되었다. 따라서, 본 논문에서 제안한 복합 미생물 배양기의 제어시스템의 효용성이 입증되었다.

• Food Science and Biotechnology
• /
• 제18권1호
• /
• pp.249-252
• /
• 2009

Two-dimensional gel electrophoresis (2-DE) was employed to assess the thermo-tolerance characteristics of Bifrdobacterium infantis ATCC 27920 to mild heat adaptation. When exposed to various heat levels, pH, and hydrogen peroxide ($H_2O_2$) stress conditions, B. infantis ATCC 27920 exhibited high level of stress resistance. Under mild-heat treatment ($46^{\circ}C$), no significant change in viability level was observed after 2 hr. Interestingly, improved viability was observed in mild-heat adapted ($46^{\circ}C$ for 1 hr) cultures exposed to $55^{\circ}C$, in comparison to control experiments. Viability was not affected by pH, bile, and $H_2O_2$ stress conditions. 2-DE analysis revealed those mild-heat adaptation up-regulated 4 proteins and down-regulated 3 proteins. Among these protein spots, isopropyhnalate dehydratase (leuD), glycosyltransferase (glgA), and ribosomal protein L5 (rp1E) were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALD1-TOF/MS).

• 마이크로전자및패키징학회지
• /
• 제30권2호
• /
• pp.65-70
• /
• 2023

나노임프린트 리소그래피(Nanoimprint lithography, NIL) 공정은 패턴 형성을 위한 공정 단순성, 우수한 패턴 형성, 공정의 확장성, 높은 생산성 및 저렴한 공정 비용이라는 이유들로 인해 많은 관심을 받고 있다. 그러나, 기존의 NIL 기술들을 통해 금속 소재 상 구현할 수 있는 패턴의 크기는 일반적으로 마이크로 수준으로 제한적이다. 본 연구에서는, 다양한 두께의 금속 기판 표면에 마이크로/나노 스케일 패턴을 직접적으로 형성하기 위한 극압 임프린트 리소그래피(extremepressure imprint lithography, EPIL) 방법을 소개하고자 한다. EPIL 공정은 자외선, 레이저, 임프린트 레지스트 또는 전기적 펄스 등의 외부 요인을 사용하지 않고 고분자, 금속, 세라믹과 같은 다양한 재료의 표면에 신뢰성 있는 나노 수준의 패터닝을 가능하게 한다. 레이저 미세가공 및 포토리소그래피로 제작된 마이크로/나노 몰드는 상온에서 높은 하중 혹은 압력을 가해 정밀한 소성변형 기반 Al 기판의 나노 패터닝에 활용된다. 20 ㎛ 부터 100 ㎛까지 다양한 두께를 갖는 Al 기판 상 마이크로/나노 스케일의 패턴 형성을 보여주고자 한다. 또한, 다목적 EPIL 기술을 통해 금속 재료 표면에서 그 형상을 제어하는 방법 역시 실험적으로 증명된다. 임프린트 리소그래피 기반 본 접근법은 복잡한 형상이 포함된 금속 재료의 표면을 요구하는 다양한 소자 응용을 위한 나노 제조 방법에 적용될 수 있을 것으로 기대한다.

• 대한방사선치료학회지
• /
• 제31권1호
• /
• pp.17-24
• /
• 2019

목 적: 본 연구는 정위적체부방사선치료(Stereotactic Body Radiation Therapy, SBRT)용으로 개발된 선형가속기 VERO치료 시, 동중심점(Isocenter) 일치성과 점선량(Point dose)의 정확성을 평가하고자 한다. 대상 및 방법: 2018년 6월부터 12월까지 본원에서 시행한 SBRT 중 무작위로 선정한 10건의 치료계획으로 분석하였다. 선형가속기의 출력 안정성을 평가하기 위해 출력검출기 PTW-LinaCheck로 출력균일성(Output constancy)을 측정하였다. Laser와 kV imaging, MV beam의 기하학적 Isocenter의 정확성을 Isocenter Phantom(Tofu Phantom, Brain Lab)을 이용해 측정하고 평가하였다. 계획선량과 치료선량의 정확성 평가는 아크릴 팬텀($30{\times}30{\times}20cm$), 이온챔버 CC-01(IBA Dosimetry)와 Electrometer(IBA Dosimetry)를 이용해 선량을 측정하여 비교 및 분석하였다. 결 과: VERO의 출력균일성을 측정한 결과 0.66 %로 계산되었다. 기하학적 Isocenter 정확성은 Phantom 내부 Ball Isocenter의 오차 값을 분석한 결과 X축 방향에서는 최대 0.4 mm, 최소 0.0 mm로 평균값 0.28 mm였고, Y축 방향에서는 최대 -0.4 mm, 최소 0.0 mm로 평균값 -0.24 mm의 결과값을 얻었다. 치료계획선량과 실제측정선량을 비교 및 분석한 결과 치료계획선량과 실제측정선량의 오차는 최대 0.97 %, 최소 0.08%로 측정되었다. 결 론: 장비의 출력선량 평균은 0.66 %로 권고기준 ${\pm}3%$에 충족하고 매우 균일하게 출력되었다. 기하학적 Isocenter 정확성 평가에서 권고기준 ${\pm}1mm$ 이내로 환자 자세의 재현성이 매우 우수하다고 생각된다. 치료계획선량과 실제측정선량의 차이는 평균 0.52 %로 권고기준 3 % 이내로 충족하여 예측한 선량을 얻을 수 있음을 확인하였다. 이 실험들을 통해 VERO장비가 SBRT에 적합하고 우수한 치료 효과를 얻을 수 있을 것으로 사료된다.

• International Journal of Railway
• /
• 제1권4호
• /
• pp.149-156
• /
• 2008

During maintenance or construction works in or at the tracks of railways, high risks for passengers and railway staff, especially for the workers on the construction site exist. The high risks result out of the movement of rail vehicles, like trains or construction vehicles, which must be faced by using any available technical and operational technologies for securing them against the environment. Therefore, it is necessary to evaluate the level of protection continuously and to identify new and innovative methods and technologies for the protection of the gang (construction worker, machines and material). Especially on construction sites at line sections with two or more parallel tracks but also with single tracks, there are still a lot of incidents and accidents mostly with seriously injured persons or fatalities. These were mainly gang members that breach the railway-loading gage. By using proper warning or protection systems, the avoidance of such accidents must be achieved. The latest developments. in gang protection systems concern on the one hand fixed barriers in the middle between the construction site and the operated track and on the other hand construction vehicles equipped with automatic warning systems. The disadvantage of such protection methods is that the gang can be warned against an approaching train but a monitoring of the gang members cannot be performed. Only one part of a potential dangerous situation will be detected. If the gang members will overhear the acoustic warning signal of the security staff and the workers will not leave the danger zone in the track, the driver of the approaching train had no chance to react to the dangerous situation. An accident is often inevitable. While the detection of acoustic warning signals by the gang members working on a construction site is very difficult, the acoustical planning of an automatic warning system has to be designed for an acoustic short range level of one meter besides the construction vehicle. The decision about the use of today's technical warning system (fixed systems, automatic warning systems, etc.) must be geared to the technical feasibility and the level of safety which is needed. Criteria for decision guidance to block a track should be developed by danger estimation and economical variables. To realize the actual jurisdiction and to minimize the hazards of railway operations by the use of construction vehicles near the tracks further developments are needed. This means, that the warning systems have to be enhanced to systems for protection, which monitor the realization of the warning signal as a precondition for giving a movement authority to a train. This method can protect against accidents caused by predictable wrongdoing. The actual state of the art technique of using a collective warning combined with additional security staff is no longer acceptable. Therefore, the Institute of Transportation System of the German Aerospace Center in Braunschweig (Germany) will develop a gang warning and protection system based upon imaging methods, with optical sensors such as video in visible and invisible ranges, radar, laser, and other. The advantage of such a system based on the possibility to monitor both the gang itself and the railway-loading gauge either of the parallel track or of the same track still in use. By monitoring both situations, the system will be able to generate a warning message for the approaching train, that there are obstacles in the track, so that the train can be stopped to prevent an accident. And also the gang workers will be warned, while they breach their area.

• 대한기계학회논문집A
• /
• 제24권1호
• /
• pp.1-6
• /
• 2000

As dies and molds have become more and more complicated in the recent years, the demand for lower cost and shorter production time is also growing stronger. Rapid prototyping and Tooling technologies are expected to be used for more rapid and lower cost tool fabrication. However the rapid tooling methods have not yet reached the level of application to the manufacturing of metallic dies and molds which require high dimensional accuracy. As the rapid tooling technology, there are the slurry casting, the powder casting, the direct laser sintering, and so on. Generally, in the slurry casting, the alumina powder and the water soluble phenol were mainly used. However, the mechanical properties of the phenol were not good enough to apply to molds directly. In this study, pure epoxy and two types of aluminium powder reinforced resin are applied to the slurry casting. The mechanical and thermal properties are better than phenol because the epoxy is the thermosetting resin. And mechanical characteristics such as shrinkage rate, hardness, surface roughness are measured for the sake of comparison. Metal powder reinforced resin molds are better than the resin tool form the viewpoint of shrinkage rate and hardness. Finally, it has been shown that the application possibility of this process is high, because the manufacturing time and cost savings are significant.

• 한방재활의학과학회지
• /
• 제26권2호
• /
• pp.61-74
• /
• 2016

Objectives The purpose of this research is to investigate recent clinical studies of Temporomandibular Joint Disorder in China. Methods We investigated recent clinical studies of Oriental Medicine therapies in traditional Chinese medical journals for Temporomandibular Joint Disorder through CNKI search. 20 clinical articles published from 2010 to 2015 were analyzed. This study examined the authors, published years, types of study designs, criteria for diagnosis and evaluation, periods, purposes of study and classified articles by techniques of treatment. Results Most of articles were classified as RCT. TMD was diagnosed by symptoms in a high proportion of articles. The criteria for evaluation that most frequently used were grading scale, but there was a lack of objectivity. The techniques of treatment were Tuina, acupuncture, herb medicine, electrotherapy, splint, PNF, congnitive behavior therapy, laser therapy, magnetic therapy. Conclusions In order to develop treatment of TMD in the Korean medicine, clinical studies for various therapies on a high level and cooperative studies between medical communities are needed.

• 한국재료학회지
• /
• 제22권5호
• /
• pp.237-242
• /
• 2012

We report on the NO gas sensing properties of Al-doped zinc oxide-carbon nanotube (ZnO-CNT) wire-like layered composites fabricated by coaxially coating Al-doped ZnO thin films on randomly oriented single-walled carbon nanotubes. We were able to wrap thin ZnO layers around the CNTs using the pulsed laser deposition method, forming wire-like nanostructures of ZnO-CNT. Microstructural observations revealed an ultrathin wire-like structure with a diameter of several tens of nm. Gas sensors based on ZnO-CNT wire-like layered composites were found to exhibit a novel sensing capability that originated from the genuine characteristics of the composites. Specifically, it was observed by measured gas sensing characteristics that the gas sensors based on ZnO-CNT layered composites showed a very high sensitivity of above 1,500% for NO gas in dry air at an optimal operating temperature of $200^{\circ}C$; the sensors also showed a low NO gas detection limit at a sub-ppm level in dry air. The enhanced gas sensing properties of the ZnO-CNT wire-like layered composites are ascribed to a catalytic effect of Al elements on the surface reaction and an increase in the effective surface reaction area of the active ZnO layer due to the coating of CNT templates with a higher surface-to-volume ratio structure. These results suggest that ZnO-CNT composites made of ultrathin Al-doped ZnO layers uniformly coated around carbon nanotubes can be promising materials for use in practical high-performance NO gas sensors.

• 대한공간정보학회지
• /
• 제23권2호
• /
• pp.39-48
• /
• 2015

최근, 무인항공촬영시스템(UAV, UAS, 또는 드론)은 자료취득을 위한 플랫폼 및 측정기기로서 사진측량의 응용분야, 특히 고밀도 측점자료(HDPC : High Density Point Clouds) 구성에 큰 관심이 모아지고 있다. 본 연구는 저가회전익 UAS 영상에 의한 시험대상지 지표면의 고밀도 측점자료를 구성하고 위치 정확도를 평가한 내용이다. 정확도 평가는 62개의 지상 검사점에 대한 Network RTK GNSS 측량 결과를 기준으로 UAS 기반 HDPC 모형의 좌표와 비교 검토하였다. 연구결과, 작업지역 정사영상 내, 검사점의 평면 및 수직 좌표성분의 평균제곱근오차(RMSE)는 각각 ${\sigma}_H={\pm}0.102m$ 및 ${\sigma}_V={\pm}0.209m$, 수직 좌표성분의 최대오차는 0.570m로서 '영상지도제작 작업규정'에 따른 축척 1:1000(출력 시, 평면위치오차 1m)의 정사영상모자익 제작이 가능하였다. 또한, 격자규격 $1m{\times}1m$, 수치지도축척 1:1000의 수치표고모델을 제작할 경우, '항공레이저측량 작업규정'제한 기준에는 약간 미흡하였지만, 소규모지역을 대상으로 회전익 무인항공촬영시스템에 의한 축척 1:1000~1:2500의 정사영상 및 수치표고모델 제작의 가능성을 확인할 수 있었다.

• 대한통합의학회지
• /
• 제7권2호
• /
• pp.1-10
• /
• 2019

Purpose : To investigate the relationship between breathing pattern disorder and joint position error (JPE) in patients with chronic low back pain (CLBP). Methods : Thirty nine patients with CLBP participated. End-tidal $CO_2$ and respiration rate (RR) were measured using a capnography. Breathing-hold time (BHT) and Nijmegen Questionnaire (NQ) were investigated. Thoracic excursion was measured with a cloth tape measurement technique. Joint position error were measured using a small laser point mounted on a lightweight headband. they were asked to relocate the head, after the neck movement on the horizontal plane. Pearson 's test was used for correlation analysis between respiratory variables and JPE in patients with CLBP. Independent t-test was used to verify the difference between thoracic and diaphragm breathing pattern in patients with CLBP. The significance level was set at 0.05. Results : There was a significant correlation between JPE (LR) and JPE (RR, EX) (r=.639, r=.813) (p<.001) and a low negative correlation with end-tidal $CO_2$ (r=-.357) (p<.05). There was a significant correlation between RR and JPE (EX) (r=.750) (p<.001). There was a low correlation between JPE (EX) and NQ (r=.333) (p<.05). There was a somewhat high negative correlation between NQ and thoracic excursion (r=-.528) (p<.001). There was a somewhat high negative correlation between thoracic excursion and JPE (LR, RR, EX) (r=-.470, r=-.484, r=-.602) (p<.001). There were no significant differences in the RR, BHT, NQ, and thoracic excursion between the thoracic and diaphragmatic breathing (p>.05). There was a significant difference in the JPE (EX), end - tidal $CO_2$, and VAS values between the thoracic and diaphragm breathing (p<.05). Conclusion : There was a correlation between JPE (EX) and NQ in patients with CLBP, and correlation between thoracic excursion and JPE (LR, RR, EX) and NQ. There was a significant difference in the JPE (EX), end-tidal $CO_2$ level, and VAS value in the comparison of thoracic breathing and diaphragm breathing. The results showed that breathing patterns and JPE were related to each other.