• Journal of Microbiology and Biotechnology
• /
• 제28권9호
• /
• pp.1554-1562
• /
• 2018

The type I interferons (IFNs) play a vital role in activation of innate immunity in response to viral infection. Accordingly, viruses have evolved to employ various survival strategies to evade innate immune responses induced by type I IFNs. For example, hepatitis E virus (HEV) encoded papain-like cysteine protease (PCP) has been shown to inhibit IFN activation signaling by suppressing K63-linked de-ubiquitination of retinoic acid-inducible gene I (RIG-I) and TANK-binding kinase 1 (TBK1), thus effectively inhibiting down-stream activation of IFN signaling. In the present study, we demonstrated that HEV inhibits polyinosinic-polycytidylic acid (poly(I:C))-induced $IFN-{\beta}$ transcriptional induction. Moreover, by using reporter assay with individual HEV-encoded gene, we showed that HEV methyltransferase (MeT), a non-structural protein, significantly decreases RIG-I-induced $IFN-{\beta}$ induction and $NF-{\kappa}B$ signaling activities in a dose-dependent manner. Taken together, we report here that MeT, along with PCP, is responsible for the inhibition of RIG-I-induced activation of type I IFNs, expanding the list of HEV-encoded antagonists of the host innate immunity.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
• /
• pp.106-111
• /
• 2001

The performance characteristics of heat pump system using the new refrigerant subcooling system were investigated. The new heat pump system has the ice storage tank to accumulate the latent heat of the refrigerant during the night-time. The heat is released to subcool the saturated refrigerant liquid at the outlet of a condenser in the daytime. The experimental apparatus is a well-instrumented heat pump which consisted of a refrigerant loop and a coolant loop. The test sections(condenser and evaporator) were made of tube-in-tube heat exchanger with the horizontal copper tube of 12.7[mm] outer diameter and 9.5[mm] inner diameter. The evaporating temperatures ranged from $-5[^{\circ}C]$ to $0[^{\circ}C]$ and the subcooling degrees of the refrigerant varied from $15[^{\circ}C]$ to $25[^{\circ}C]$. The test of the ice storage was carried out at evaporating temperature of $-10[^{\circ}C]$ and the ice storage mode is an ice-on-coil type. The main results were summarized as follows ; The refrigerant mass flow rate and compressor shaft power of the heat pump system were independent of the subcooling degrees. The cooling capacity o the heat pump system increases as the evaporating temperature and subcooling degree increases. The cooling capacity of the heat pump system is about 25 to 30% higher than that of normal heat pump system. The COP of the heat pump system which subcooled the refrigerant liquid at the outlet of the condenser is about 28% higher than that of the normal heat pump system.

• 한국가스학회지
• /
• 제3권3호
• /
• pp.58-64
• /
• 1999

멤브레인 방식의 저장탱크 제작에서 가장 중요한 설계 파라메타인 멤브레인 유니트의 피치에 관한 응력거동 문제를 유한요소법을 사용하여 해석하였고, 이 결과를 기존의 피치설계치수와 비교 검토하였다. 본 연구에서 고려한 링 마디식 멤브레인의 경우 피치의 길이를 어떻게 설정하든지 초대형 탱크의 경우에서는 안전성 문제가 발생하지 않았다. 그러나 반복하중에 의한 피로강도가 문제되는 선박용 멤브레인의 경우에는 피치를 짧게 설계하는 것이 유리하다는 것을 보여주고 있다. 멤브레인 주름의 변형거동을 보면 주름의 높이 방향 변형이 폭에 비하여 $15{\~}50\%$ 정도 더 크게 발생하고, $-162^{\circ}C$의 초저온에 의한 변형은 액압에 의한 변형과 비교할 때 그리 크지는 않음을 보여준다.

• 설비공학논문집
• /
• 제28권10호
• /
• pp.387-393
• /
• 2016

A ground source heat pump system maintains a constant efficiency due to its stable heat source and radiant heat temperature which provide a more effective thermal performance than that of the air source heat pump system. As an eco-friendly renewable energy source, it can reduce electric power and carbon dioxide. In this study, we analyzed one year of data from a web based remote monitoring system to estimate the thermal performance of GSHP with the capacity of 3RT, which is installed in a low energy house located in Daejeon, Korea. This GSHP system is a hybrid system connected to a solar hot water system. Cold and hot water stored in a buffer tank is supplied to six ceiling cassette type fan coil units and a floor panel heating system installed in each room. The results are as follows. First, the GSHP system was operated for ten minutes intermittently in summer in order to decrease the heat load caused by super-insulation. Second, the energy consumption in winter where the system was operated throughout the entire day was 7.5 times higher than that in summer. Moreover, the annual COP of the heating and cooling system was 4.1 in summer and 4.2 in winter, showing little difference. Third, the outlet temperature of the ground heat exchanger in winter decreased from $13^{\circ}C$ in November to $9^{\circ}C$ in February, while that in summer increased from $14^{\circ}C$ to $17^{\circ}C$ showing that the temperature change in winter is greater than that in summer.

• 해양환경안전학회지
• /
• 제23권2호
• /
• pp.208-215
• /
• 2017

원유나 벙커C유와 같은 지속성 기름이 해상에 유출되면 풍화과정을 거쳐 점도가 높아지고, 부유 쓰레기와 섞이게 되면 이를 수거할 수 있는 장비는 매우 제한적이다. 본 연구에서는 기존 유회수기의 외부에 위치한 부속장치들을 본체 내부로 배치하고, 컨베이어 벨트와 강제유입장치인 스위퍼 및 부력체를 탑재한 수집조로 구성하여 자항과 리모트컨트롤이 가능한 무인 컨베이어 벨트식 부유쓰레기 및 고점도유 회수장비를 개발하였다. 실해역 테스트에서 30 m의 거리를 1.2 knots의 속도로 자항하며, 전 후, 좌 우에서 안정적인 균형유지와 구동부의 정상작동을 확인하였다. 임시저장조를 이용한 유회수 성능테스트 결과, 최소 $7.8k{\ell}/h$에서 최대 $23.3k{\ell}/h$까지 유출유 회수가 가능하였다. 또한, 페트병 등 부유쓰레기와 유출된 기름이 혼합된 조파수조에서 실시한 회수량 측정 테스트 결과는 $7.7k{\ell}/h$로 나타났다. 본 연구를 통해 개발된 장비가 해상기름오염사고 시 현장에 신속하게 투입된다면 방제능력 향상에 기여할 수 있을 것으로 기대하며, 현재 운용중인 Portable 유회수기의 성능개선 연구에 활용될 수 있을 것으로 판단된다.

• 생물환경조절학회지
• /
• 제28권4호
• /
• pp.420-428
• /
• 2019

본 연구에서는 고설 딸기 관부(크라운부) 난방시스템을 전기 온수 보일러, 축열조, 순환 펌프, 관부난방 배관(백색 연질 PE관, 관경 16mm) 및 온도 제어반으로 구성하였다. 관부(크라운부) 난방의 경우 난방 배관을 딸기 관부에 최대한 밀착될 수 있도록 설치하고 배관 위치를 원예용 고정핀으로 고정하였다. 또한 관부 난방시스템의 에너지 효율을 증진하기 위해 축열조 온수 온도를 $20{\sim}23^{\circ}C$, 관부 온도를 $13{\sim}15^{\circ}C$로 관리하였다. 관부난방은 전기 온수보일러를 이용하여 $20{\sim}23^{\circ}C$의 온수를 축열조에 저장하고 순환펌프를 제어하기 위한 온도 센서를 딸기의 관부에 최대한 근접하여 설치하고 온도를 감지함으로써 관부(크라운부)를 집중적으로 난방하는 방식이다. 시험 온실의 난방 처리는 공간 난방 $4^{\circ}C$ + 관부난방(처리 1), 공간 난방 $8^{\circ}C$ (대조구), 공간 난방 $6^{\circ}C$ + 관부난방(처리 2)로 처리하였다. 각 난방처리는 온실 1동에 딸기를 980주를 심었으며, 재배방법은 표준재배법에 준해서 재배하였다. 난방 에너지 소비에 대한 비교시험은 2017년 11월 8일부터 2018년 3월 30일까지 수행되었다. 소비된 누적 전력량은 등유 사용량으로 환산하였고, 등유 소비량은 공간난방 $8^{\circ}C$(대조구)의 경우 1,320L(100%), 공간난방 $4^{\circ}C$ + 관부난방의 경우 928L(70.3%), 공간난방 $6^{\circ}C$ + 관부난방의 경우 1,161L (88%)로 계측되었다. 공간난방 $4^{\circ}C$ + 관부난방(처리 1) 및 공간난방 $6^{\circ}C$ + 관부난방(처리 2)은 $8^{\circ}C$ 공간난방(대조구)에 비해 생육 저하, 수확시기의 지연 등이 없이 비슷하게 딸기 수확이 가능하였으며, 29.7% 및 12%의 난방 에너지가 절감되는 것으로 분석되었다.

• 센서학회지
• /
• 제16권1호
• /
• pp.44-51
• /
• 2007

A hybridized simulator for generating blood pressure waveform is proposed to study the remedy and/or evaluation of the conventional sphygmomanometer utilizing the oscillometric method which is widely applied. The blood pressure of a flowing fluid was controlled for the blood vessel's condition caused by a rhythmical and periodical contraction/relaxation because of the special excitatory and conductive system of the heart. In this study, a hybridized controller composed of the PI feedback controller and the feedforward controller. The inverse dynamics function is proposed to operating the control valve while the pressure is applied in an oil pressure tank. The proposed hybrid simulator reproducing the blood pressure waveform in an artificial blood vessel has kept the control performance consistent over all range. Based on these results, the proposed simulators could be applied to the development and compensation of the non invasive sphygmomanometer type as well as to study the characteristics of the blood pressure and blood vessel.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2004년도 춘계 학술대회논문집
• /
• pp.208-213
• /
• 2004

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in- pool type, is under normal operation since it reached the initial critical in February 1995. The HANARO is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and is under developing a target handling tool for loading and unloading it in a circular flow tube (OR-5). A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube by jet flow. This paper is described an analytical analysis to calculate the hole size of a orifice inserted in the circular irradiation hole and to study the flow characteristics through the guide tube under reactor normal operation and loading the target. As results, the results show that the hole size of orifice was 31 mm of the inner diameter to suppress the guide tube jet flow and the coolant safely cooled the target of fission moly after inserting the orifice to the flow tube.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2004년도 춘계 학술대회논문집
• /
• pp.214-219
• /
• 2004

The HANARO, a multi-purpose research reactor of 30 MWth, open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. The HANARO is composed of inlet plenum, grid plate, core channel with flow tubes and chimney. The reactor core channel is located at about twelve m (12 m) depth of the reactor pool and cold by the upward flow that the coolant enters the lower inlet of the plenum, rises up through the grid plate and the core channel and exit through the outlet of chimney. A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be Quickly raised up to the top of the chimney through the guide tube by jet flow. This paper is described an analytical analysis to study the flow behavior through the guide tube under reactor normal operation and unloading the target. As results, it was conformed through the analysis results that the flow rate, about fourteen kilogram per second (14 kg/s) suppressed the guide tube jet and met the design cooling flow rate in a circular flow tube, and that the fission moly target cooling flow rate met the minimum flow rate to cool the target.

• 한국환경보건학회지
• /
• 제22권2호
• /
• pp.96-103
• /
• 1996

The objectives of this study were to examine the biodegradation of phenol using the anaerobic fluidized bed reactor(AFBR). Mixed microorganisms were selected from the anaerobic digestion tank, and could be adapted to high concentration of phenol by increasing the phenol concentration 600-3600 mg/l step by step. The results were summarized as follows: 1. The average removal efficiency of phenol was 90%, decreased by increasing concentration of phenol, and then a shock range was 1200~2400 ppm. 2. The production rate of biogas in overall limits was proportional to the concentration of influent phenol. 3. At steady state, compositions of gases were $CH_4$ 55~60%, $C0_2$ 34~43%, respectively. These were similar to that of the theoretical estimates. 4. The production rates of biogas and methane per the molarity of phenol removed were linearly increased, 56.45 l gas/mol-phenol and 29.20 l $CH_4/mol$-phenol. Using this biogas, the recoverable energy was 269.1 kcal/mol phenol. It was 120.2 kcal/g-COD, transforming into the chemical oxygen demand. 5. The bulk of microorganisms existed in suspended section of fluidized bed with type of biofilm and its concentration was 340 mg/g-media. In conclusion, the anaerobic treatment of pure phenol was possible and its removal efficiency, introducing the AFBR, was successful. Also toxic organic compound such as phenol was biodegradable and was recoverable as resource of energy.