• 한국어류학회지
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• 제20권4호
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• pp.239-247
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• 2008

무지개송어(체장 $17.1{\pm}1.0cm$, 체중 $68.4{\pm}2.0g$)의 수온변화에 따른 생리적 반응의 단기적 지표로서 산소소비율, 호흡수, 헤모글로빈 함량 변화 및 내성 상한 온도를 조사하였다. 실험 수온은 $15^{\circ}C$를 중심으로 낮은 온도 쪽으로는 4, 5, 6, 7 및 $10^{\circ}C$, 높은 온도 쪽으로는 17, 20, 23, 26 및 $28^{\circ}C$에서 각각 적응시켜 산소소비량과 호흡수를 측정하였다. 수온의 하강과 상승은 $15^{\circ}C$에서 사육하던 무지개 송어를 1일 $1^{\circ}C$씩 순차 적응시키면서 각 수온에 7일간 적응시켰다. 무지개송어는 수온이 $23^{\circ}C$ 이상이 되면 산소소비율, 호흡수 및 헤모글로빈 함량에 변화를 가져오면서 체내 항상성이 급격하게 낮아지는 것으로 나타났다. 또한 생존 상한수온은 $28^{\circ}C$로 나타났다. 무지개송어가 무리없이 생활할 수있는 온도 범위는 $10{\sim}20^{\circ}C$로서 $10{\sim}15^{\circ}C$의 낮은 온도에서는 낮은 온도쪽으로, $15{\sim}20^{\circ}C$의 높은 온도에서는 높은 온도쪽으로 $5^{\circ}C$ 이상 급격한 변화를 주지 않는 것이 무지개송어의 생리활력에 현저한 변화가 나타나지 않는 것으로 조사되었다.

• Ocean Systems Engineering
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• 제5권3호
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• pp.139-160
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• 2015

The global performance of the 5MW OC4 semisubmersible floating wind turbine in random waves was numerically simulated by using the turbine-floater-mooring fully coupled and time-domain dynamic analysis program FAST-CHARM3D. There have been many papers regarding floating offshore wind turbines but the effects of second-order wave-body interactions on their global performance have rarely been studied. The second-order wave forces are actually small compared to the first-order wave forces, but its effect cannot be ignored when the natural frequencies of a floating system are outside the wave-frequency range. In the case of semi-submersible platform, second-order difference-frequency wave-diffraction forces and moments become important since surge/sway and pitch/roll natural frequencies are lower than those of typical incident waves. The computational effort related to the full second-order diffraction calculation is typically very heavy, so in many cases, the simplified approach called Newman's approximation or first-order-wave-force-only are used. However, it needs to be justified against more complete solutions with full QTF (quadratic transfer function), which is a main subject of the present study. The numerically simulated results for the 5MW OC4 semisubmersible floating wind turbine by FAST-CHARM3D are also extensively compared with the DeepCWind model test results by Technip/NREL/UMaine. The predicted motions and mooring tensions for two white-noise input-wave spectra agree well against the measure values. In this paper, the numerical static-offset and free-decay tests are also conducted to verify the system stiffness, damping, and natural frequencies against the experimental results. They also agree well to verify that the dynamic system modeling is correct to the details. The performance of the simplified approaches instead of using the full QTF are also tested.

• Interdisciplinary Bio Central
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• 제3권3호
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• pp.10.1-10.8
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• 2011

Introduction: Hash functions are computer algorithms that protect information and secure transactions. In response to the NIST's "International Call for Hash Function", we developed a biological hash function using the computing capabilities of bacteria. We designed a DNA-based XOR logic gate that allows bacterial colonies arranged in a series on an agar plate to perform hash function calculations. Results and Discussion: In order to provide each colony with adequate time to process inputs and perform XOR logic, we designed and successfully demonstrated a system for time-delayed bacterial growth. Our system is based on the diffusion of ${\ss}$-lactamase, resulting in destruction of ampicillin. Our DNA-based XOR logic gate design is based on the op-position of two promoters. Our results showed that $P_{lux}$ and $P_{OmpC}$ functioned as expected individually, but $P_{lux}$ did not behave as expected in the XOR construct. Our data showed that, contrary to literature reports, the $P_{lux}$ promoter is bidirectional. In the absence of the 3OC6 inducer, the LuxR activator can bind to the $P_{lux}$ promoter and induce backwards transcription. Conclusion and Prospects: Our system of time delayed bacterial growth allows for the successive processing of a bacterial hash function, and is expected to have utility in other synthetic biology applications. While testing our DNA-based XOR logic gate, we uncovered a novel function of $P_{lux}$. In the absence of autoinducer 3OC6, LuxR binds to $P_{lux}$ and activates backwards transcription. This result advances basic research and has important implications for the widespread use of the $P_{lux}$ promoter.

• Nuclear Engineering and Technology
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• 제53권4호
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• pp.1218-1223
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• 2021

A hydrophobic ionic liquid including an amino moiety ([DiOcAPmim][NTf₂]) was synthesized. Its extraction behaviors towards Pd(II), Ru(III), Rh(III) were investigated in nitric acid aqueous solution as a function of contact time, effect of concentration of nitric acid, effect of temperature, and effect of co-existing metal ions. The extraction kinetics of Pd(II) was fairly fast and extraction equilibrium can be attained within only 5 min under the [HNO₃] = 2.05 M. When [HNO₃]< 1 M, the extraction percentage of Pd(II), Ru(III), Rh(III) were all above 80%. When [HNO₃] reached 2 M, all of the extraction percentage decreased and in an order of Pd(II)>Ru(III)>Rh(III). When [HNO₃]> 2 M, the extraction performance gradually recovered. The effect of temperature can slightly affect the extraction performance of Pd(II). Furthermore, in simulated high-level liquid waste, [DiOcAPmim][NTf₂] showed a better preference towards Pd(II) under the interference of various other co-existing metal ions.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.367-375
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• 2020

This paper presents an integrated analysis about dynamic performance of a Floating Offshore Wind Turbine (FOWT) OC4 DeepCwind with semi-submersible platform under real sea environment. The emphasis of this paper is to investigate how the wave mean drift force and slow-drift wave excitation load (Quadratic transfer function, namely QTF) influence the platform motions, mooring line tension and tower base bending moments. Second order potential theory is being used for computing linear and nonlinear wave effects, including first order wave force, mean drift force and slow-drift excitation loads. Morison model is utilized to account the viscous effect from fluid. This approach considers floating wind turbine as an integrated coupled system. Two time-domain solvers, SIMA (SIMO/RIFLEX/AERODYN) and FAST are being chosen to analyze the global response of the integrated coupled system under small, moderate and severe sea condition. Results show that second order mean drift force and slow-drift force will drift the floater away along wave propagation direction. At the same time, slow-drift force has larger effect than mean drift force. Also tension of the mooring line at fairlead and tower base loads are increased accordingly in all sea conditions under investigation.

• 대한이식학회지
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• 제28권3호
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• pp.154-159
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• 2014

Background: Lung transplantation (LTx) is a life-saving treatment for patients with end-stage lung disease; however, the shortage of donor lungs has been a major limiting factor to increasing the number of LTx. Growing experience following LTx using donor lungs after cardiac death (DCD) has been promising, although concerns remain. The purpose of this study was to develop a DCD lung harvest model using an ex vivo lung perfusion (EVLP) system and to assess the function of presumably damaged lungs harvested from the DCD donor in pigs. Methods: The 40 kg pigs were randomly divided into the control group with no ischemic lung injury (n=5) and the study group (n=5), which had 1 hour of warm ischemic lung injury after cardiac arrest. Harvested lungs were placed in the EVLP circuit and oxygen capacities (OC), pulmonary vascular resistance (PVR), and peak airway pressure (PAP) were evaluated every hour for 4 hours. At the end of EVLP, specimens were excised for pathologic review and wet/dry ratio. Results: No statistically significant difference in OC (P=0.353), PVR (P=0.951), and PAP (P=0.651) was observed in both groups. Lung injury severity score (control group vs. study group: 0.700±0.303 vs. 0.870±0.130; P=0.230) and wet/dry ratio (control group vs. study group: 5.89±0.97 vs. 6.20±0.57; P=0.560) also showed no statistically significant difference between the groups. Conclusions: The function of DCD lungs assessed using EVLP showed no difference from that of control lungs without ischemic injury; therefore, utilization of DCD lungs can be a new option to decrease the number of deaths on the waiting list.

• 조명전기설비학회논문지
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• 제14권1호
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• pp.109-117
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• 2000

본 논문은 고주파 유도가열용 전원에 사용되는 인버터에 WVF 기능을 부여한 풀-브릿지형 복공진 고주파 인버터회로를 제시하였다. 제안한 인버터는 직렬공진회로의 전류를 병렬공진회로의 주입전류로 사용하기 때문에 스위치의 전류 분담을 감소시킬 수 있으며, 또한 본 논문은 Phase-shift를 이용하여 스위칭 주파수와는 무관한 독립 출력 제어를 행하였다. 회로의 해석은 정규화 파라메타를 도입하여 범용성 있게 기술하였고, 인버터 특성을 스위칭 주파수, Phase-shift의 위상차각($\phi$) 변화와 제 파라메타에 따라 특성평가를 행하였다. 또한, 이론해석에서 얻은 특성값을 기초로 한 회로 설계 기법의 일 예도 제시하였다. 첨가해서, 실험을 통해 이론 해석의 타당성을 검증하였으며, 향후 유도가열 응용, OC-OC 컨버터 등의 전원 시스템에 웅용 가능성을 보여주고 있다.

• 한국식품영양과학회지
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• 제40권7호
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• pp.1048-1052
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• 2011

각기 다른 치환도를 가진 초산 고구마전분 페이스트의 유동특성 및 투과도 그리고, 이들 전분 겔의 냉.해동안정성 및 강도가 치환도의 함수로 분석되었다. 유동특성 측정 결과 power law 모델식과 Casson 모델식에 잘 적용되었으며, 높은 shear-thinning 거동을 가지고 있는 것으로 나타났다. 특정한 온도 범위($25{\sim}70^{\circ}C$)에서 전분 페이스트의 겉보기 점도($\eta_{a,100}$)의 온도 의존성은 Arrhenius 모델식에 잘 적용되었으며 초산 고구마전분이 천연전분에 비해 더 낮은 온도 의존성을 나타내었다. 전분 페이스트 이수현상 측정에서는 초산화에 의해 이수현상이 감소하는 것으로 나타났으며, 치환도가 증가할수록 낮아지는 것으로 나타났다. 겔 강도 측정에서도 초산화에 의해 겔 강도가 감소하는 것으로 나타났으며, 치환도가 증가할수록 겔 강도는 감소하는 것으로 나타났다. 페이스트 투과도(% T) 측정에서 초산전분은 천연전분 보다 투과도가 높은 것으로 나타났다.

• 한국해양환경ㆍ에너지학회지
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• 제12권3호
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• pp.173-180
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• 2009

2006년 UN 총회 이후, 국제사회에서 해양쓰레기에 대한 문제 인식이 증대되고 있다. 이에 따라 UN 산하기관인 UN 환경연합/지역해 그리고 국제연합식량농업기구(FAO) 뿐만아니라 전세계 최대 해양보전민간단체인 해양보전(OC)에서도 해양쓰레기에 관한 자료를 모으기 시작했고, 보고서를 통하여 각국정책, 기술, 실천계획등을 발표하고 있다. 해양쓰레기의 국제적 관심이 증가됨에 따라 국내 해양쓰레기 정책이 국제사회에 롤 모델로서 위치를 인정받고 있다. 1999년도에 본격적으로 시작된 국내의 해양쓰레기 정책은 중앙정부, 공단 및 협회, 정부출연기관, 시민단체가 공동으로 만들어낸 작품이기도 하다. 최근 국내해양쓰레기 관리 기본계획상에 제시되어 있는 해양쓰레기 전문센터의 역할과 함께 국내 해양쓰레기 관리에 있어 향후 나아가야 할 방향에 대해서도 기술하였다. 중앙정부 주도형인 국내 해양쓰레기 정책이 민간주도 그리고 오염원인자 부담원칙이 정립되는 시기까지는 전기관 및 전국민이 해양환경에 애정어린 관심과 노력이 요구된다.

• Molecules and Cells
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• 제42권11호
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• pp.810-819
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• 2019

For physiological or pathological understanding of bone disease caused by abnormal behavior of osteoclasts (OCs), functional studies of molecules that regulate the generation and action of OCs are required. In a microarray approach, we found the suppression of tumorigenicity 5 (ST5) gene is upregulated by receptor activator of nuclear $factor-{\kappa}B$ ligand (RANKL), the OC differentiation factor. Although the roles of ST5 in cancer and ${\beta}-cells$ have been reported, the function of ST5 in bone cells has not yet been investigated. Knockdown of ST5 by siRNA reduced OC differentiation from primary precursors. Moreover, ST5 downregulation decreased expression of NFATc1, a key transcription factor for osteoclastogenesis. In contrast, overexpression of ST5 resulted in the opposite phenotype of ST5 knockdown. In immunocytochemistry experiments, the ST5 protein is colocalized with Src in RANKL-committed cells. In addition, ST5 enhanced activation of Src and Syk, a Src substrate, in response to RANKL. ST5 reduction caused a decrease in RANKL-evoked calcium oscillation and inhibited translocation of NFATc1 into the nucleus. Taken together, these findings provide the first evidence of ST5 involvement in positive regulation of osteoclastogenesis via Src/Syk/calcium signaling.