• Journal of Microbiology and Biotechnology
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• 제16권9호
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• pp.1422-1428
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• 2006

An ABC transporter apparatus of the Gram-negative bacterial type I secretion pathway can be used as a secretory protein expression system in Escherichia coli. Four types of coexpression systems for the Pseudomonas fluorescens lipase gene, tliA, and its cognate ABC transporter gene cluster, tliDEF, were constructed. When the relative expression levels were changed by adding different concentrations of IPTG, the secretion (16.9 U/ml of culture) of TliA in E. coli [pTliDEFA-223+pACYC184] was significantly higher than E. coli [pKK223-3+pTliDEFA-184] secreting the lowest level of TliA (5.2 U/ml of culture). Maximal accumulation of the lipase secreted occurred in the mid-exponential phase, implying that the efficient protein secretion via an ABC transporter was restricted only to actively growing cells. Finally, the secretion level of TliA in E. coli [pTliDEFA-223+pACYC184] was increased to 26.4 U/ml by inducing gene expression at the culture initiation time. These results indicate that a significant increase in the ABC transporter-dependent protein secretion can be achieved by simply controlling the relative expression levels between the ABC transporter and its passenger protein, even in the recombinant E. coli cells.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.40.2-40.2
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• 2009

이 연구에서는 달천이(TLI: Trans Lunar Injection) 및 달포획(LOI: Lunar Orbit Injection) 기동 시 대전 지상국의 가시성을 고려한 최적의 임무를 설계하였다. TLI 기동은 탐사선이 지구 주차궤도에서 지구-달 천이궤적으로 진입하기 위하여 주어지는 기동이며, LOI 기동은 탐사선이 지구-달 천이궤적에서 달의 중력권으로 진입하기 위하여 주어지는 기동이다. TLI 및 LOI 기동 시 대전 지상국에서의 가시성의 확보는 실제적인 미래 한국의 달 탐사를 대비하였을 때 중요한 요소이다. 따라서 이 연구에서는 TLI 및 LOI 기동 시 대전 지상국에서의 가시성을 모두 고려하여, 최소연료로 지구 주차궤도에서 달 임무궤도 진입까지의 모든 단계에 대해 임무설계를 실시하였다. TLI 및 LOI 기동 시 추력은 순간 추력(Impulsive thrust)로 가정하였으며, KSLV-II 발사체의 성능을 적용하여 설계하였다. 임무 설계 시 태양, 지구, 달의 섭동력을 고려한 N체 운동 방정식을 탐사선에 적용하였으며, 지구의 비대칭 중력장, 태양 복사압, 달의 J2 섭동에 의한 영향도 고려하였다. JPL의 정밀 천체력인 DE405를 사용하였고, 상용 소프트웨어인 SNOPT(Spares Nonlinear OPTimizer)를 이용하여 비행 궤적의 최적해를 도출하였다. 임무 설계 결과를 통해, 대전 지상국의 가시성을 고려한 TLI 및 LOI 기동의 크기에 의한 임무설계의 분석을 수행하였다. 또한 최적화된 달 탐사 임무의 단계별 기동의 크기와 지구-달 천이 궤적의 형상 및 다양한 임무 요소들의 해석을 도출하였다.

• Journal of Astronomy and Space Sciences
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• 제27권3호
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• pp.195-204
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• 2010

The optimal Earth-Moon transfer trajectory considering spacecraft's visibility from the Daejeon ground station visibility at both the trans lunar injection (TLI) and lunar orbit insertion (LOI) maneuvers is designed. Both the TLI and LOI maneuvers are assumed to be impulsive thrust. As the successful execution of the TLI and LOI maneuvers are crucial factors among the various lunar mission parameters, it is necessary to design an optimal lunar transfer trajectory which guarantees the visibility from a specified ground station while executing these maneuvers. The optimal Earth-Moon transfer trajectory is simulated by modifying the Korean Lunar Mission Design Software using Impulsive high Thrust Engine (KLMDS-ITE) which is developed in previous studies. Four different mission scenarios are established and simulated to analyze the effects of the spacecraft's visibility considerations at the TLI and LOI maneuvers. As a result, it is found that the optimal Earth-Moon transfer trajectory, guaranteeing the spacecraft's visibility from Daejeon ground station at both the TLI and LOI maneuvers, can be designed with slight changes in total amount of delta-Vs. About 1% difference is observed with the optimal trajectory when none of the visibility condition is guaranteed, and about 0.04% with the visibility condition is only guaranteed at the time of TLI maneuver. The spacecraft's mass which can delivered to the Moon, when both visibility conditions are secured is shown to be about 534 kg with assumptions of KSLV-2's on-orbit mass about 2.6 tons. To minimize total mission delta-Vs, it is strongly recommended that visibility conditions at both the TLI and LOI maneuvers should be simultaneously implemented to the trajectory optimization algorithm.

• 한국정보통신학회논문지
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• 제14권2호
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• pp.351-359
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• 2010

본 논문에서는 선박의 통합정보처리를 위해 표준화된 IEC 61162-4 기반 TLI 프로토콜의 전송 알고리즘을 제안하고, 제안된 알고리즘을 기반으로 프로토콜을 설계 및 구현한다. 구현된 프로토콜은 TCP/IP 기반의 프로토콜로서 IEC 61162-4에서 제안하고 있는 MAU와 LNA의 표준에 따른 통신 프로토콜이며, 클라이언트/서버 모델을 기반으로 한 네트워크 구조에서 데이터 전송이 이루어진다. 개발된 TLI 프로토콜은 하나의 호스트 내에 MAU와 LNA간의 통신과 서로 다른 호스트의 LNA 간 통신이 이루어지며, 하나의 LNA에 대해 다양한 서비스를 제공하기 위해 멀티 MAU 구조로 구현된다. 표준 규격과 제안된 전송 알고리즘에 따라 객체지향 기법을 이용하여 프로토콜 설계 및 구현이 되었으며, 실제 선박에서 사용될 수 있는 간단한 네트워크 환경에서 실험을 하여 성공적으로 데이터 송수신이 됨을 확인할 수 있었다.

• 한국임상수의학회지
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• 제18권1호
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• pp.7-13
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• 2001

Depending on the degree of exocrine pancreatic insufficiency, there are inconsistent values in the serum trypsin-like immunoreactivity (TLI), hematology, and serology. To determine the correlation between those values and complete pancreatic insufficiency, 10 pancreatectomized dogs as the treated group and 10 sham operation dogs as control group were used. The entire treated group showed significant decrease in serum TLI level from 2.63$\pm$0.20 ng/ml (day 0) to 1.81$\pm$0.43 ng/ml at day 1 after the pancreatectomy (p<0.05) and the decline maintained till the end of the experiment. Blood glucose level gradually increased, but albumin level showed significant decrease (p<0.05) at day 1 and maintained the decline. Three clinical signs were observed such as depression, vomiting, and diarrhea. The entire treated group showed diarrhea throughout the experiment, but depression and vomiting were gradually diminished. The activity of serum alkaline phosphatase in the treated group increased till day 2 then decreased, on the other hand, control group showed continuous increase till day 4, and then decreased. Only experimental group showed the increased alanine aminotransferase activity at day 1. Serum lipase activity in the treated group jumped up at day 1 and then dropped down, which was even lower than the control. Regarding serum amlyase activity gradually decreased. According to these results, the assay of trypsin-like immunoreactivity showed the consistent result, so it suggests that TLI is an useful tool to determine the pancreatic exocrine function and possible diagnosis of exocrine pancreatic insufficiency compared to the simple assay of plasma amylase and lipase.

• 한국임상수의학회지
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• 제35권5호
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• pp.240-242
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• 2018

A 1-year-old, female Bengal tiger (Panthera tigris tigris) presented signs of weight loss and dark browncolored diarrhea. On fecal examination, numerous intact and broken red blood cells were found, but both parasites and inflammatory signs were absent. No significant findings were seen in serum biochemistry profiles, including electrolytes, with negative feline pancreatic lipase immunoreactivity (fPLI). Diagnostic kits using feces or peripheral blood were negative for feline parvovirus, feline coronavirus, feline immunodeficiency virus, and feline leukemia virus. Based on the result of feline trypsin-like immunoreactivity (fTLI) concentration ($4.6{\mu}g/L$), the tiger was provisionally diagnosed to have exocrine pancreatic insufficiency (EPI). After this diagnosis, pancreatic enzymes were prescribed. The feces of the tiger returned to normal form and her weight was increasing. EPI is uncommon and not described extensively in Felidae, including domestic cats. Feline EPI is associated with a variety of non-specific signs and it should be considered in the differential diagnosis of cases presenting with weight loss, diarrhea, and other gastrointestinal signs. In this case, the patient was strongly suspected to have EPI based on the very low fTLI concentration, though the concentration of fTLI in tigers has not yet been determined. This is the first report to present a suspected EPI case in Bengal tigers.

• Journal of Power Electronics
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• 제13권5호
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• pp.806-813
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• 2013

This paper aims to compare the performance of three phase induction motor drives using Five Leg Inverter (FLI) and Three Leg Inverter (TLI) configurations. An Indirect Field Oriented Control (IFOC) method using a TLI is well established and incorporated for high performance speed drives in various industries. The FLI dual motor drive system on the other hand shows good workability in the independent control of two induction motor drives simultaneously. In this experiment, the IFOC method is utilized for both drive systems, and Space Vector Pulse Width Modulation (SVPWM) is used to generate pulses for both inverters. For the FLI, the Double Zero Sequence (DZS) Injection technique is used to generate the modulation signal. The complete experiment setup is done by using a DSpace 1103 controller board. The individual motor performances are analyzed using similar schemes, equipment setups and controller parameter values. The results show similar speed performance response capability between the single motor operation using a TLI system and the two motor operation using a FLI system based on the variable speed range either in forward or reverse operation. They also show similar load rejection abilities. However, the single motor with a TLI has a better power quality aspect such as ripple current and total harmonics distortion (THD).

• 한국항공우주학회지
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• 제38권10호
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• pp.998-1011
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• 2010

본 연구에서는 미래 한국의 달탐사에 대비, 제한추력을 이용한 최적의 지구-달 천이궤적 설계를 수행하였다. 보다 실제적인 임무 시나리오 설계를 위해 달 천이 (Trans Lunar Injection, TLI) 기동에 사용되는 발사체 상단 킥모터의 추력 성능을 제한하였다. 이를 바탕으로 지구 출발부터 달 근접에 이르는 지구-달 천이비행궤적이 설계되었으며, 제한추력을 이용하여 설계된 비행 궤적의 최적화 결과와 순간추력을 이용하여 최적화된 결과가 비교 분석되었다. 만약 순간추력을 이용해 도출된 예비 임무 설계의 결과가 제한추력을 가정한 임무 설계를 위해 응용될 경우, 가정된 제한추력의 크기에 따라 다양한 범위의 기동량의 차이가 발생 할 수 있어 이에 따른 충분한 고려가 이루어져야 함을 확인하였다. 본 연구에서 제시된 제한추력을 이용한 달탐사 임무궤적 설계/해석 결과는 미래 한국의 달탐사를 대비하는데 있어 다양한 사전 지식을 제공할 것이며 장차 상세한 임무설계를 위한 알고리즘의 기반으로 사용될 수 있다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.83-91
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• 2014

This paper presents a capacitive readout circuit for tri-axes microaccelerometer with sub-fF offset calibration capability. A charge sensitive amplifier (CSA) with correlated double sampling (CDS) and digital to equivalent capacitance converter (DECC) is proposed. The DECC is implemented using 10-bit DAC, charge transfer switches, and a charge-storing capacitor. The DECC circuit can realize the equivalent capacitance of sub-fF range with a smaller area and higher accuracy than previous offset cancelling circuit using series-connected capacitor arrays. The readout circuit and MEMS sensing element are integrated in a single package. The supply voltage and the current consumption of analog blocks are 3.3 V and $230{\mu}A$, respectively. The sensitivities of tri-axes are measured to be 3.87 mg/LSB, 3.87 mg/LSB and 3.90 mg/LSB, respectively. The offset calibration which is controlled by 10-bit DECC has a resolution of 12.4 LSB per step with high linearity. The noise levels of tri-axes are $349{\mu}g$/${\sqrt}$Hz, $341{\mu}g$/${\sqrt}$Hz and $411{\mu}g$/${\sqrt}$Hz, respectively.

• KSBB Journal
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• 제24권4호
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• pp.393-396
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• 2009

단백질을 동물세포내부로 직접 주입할 수 있는 살모넬라 균주의 T3SS를 활용하여 모델 단백질인 lipase를 세포외부로 분비하는 시스템을 제작하였다. T3SS의 effector 단백질인 SlrP, SptP의 N-말단부분과 lipase를 fusion하였다. Lipase 분비실험의 결과 S. typhimurium SL1344 (sptP-tliA) 균주의 경우 lipase 활성도가 약 2.6배 증가하는 결과를 얻을 수 있었다. 본 실험결과를 바탕으로 T3SS에 관한 연구가 더욱 활발히 이루어진다면, T3SS를 신개념 약물전달시스템으로 활용이 가능해 지리라 예상된다.