• 제목/요약/키워드: TCV

검색결과 17건 처리시간 0.026초

압력 평형식 온도조절 밸브 성능 향상을 위한 연구 (A Study on the Performance Improvement of Pressure Compensating Temperature Control Valve)

  • 김태안;김윤제
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.671-674
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    • 2002
  • Pressure compensating temperature control valve(TCV) is one of the important control devices, which is used to maintain the constant temperature of working fluid in power and chemical plants. The ratio of cylinder hole diameters of inlet and outlet is the main design parameters of TCV. So this needs to be investigated to improve the function of control of temperature and void fraction. In this study, numerical analysis is carried out with various ratios of cylinder hole diameters of the inlet and outlet in the TCV. Especial1y, the distribution of the static pressure Is investigated to calculate the new coefficient($C_{\upsilon}$) and resistance coefficient(K). The governing equations are derived from making using of three-dimensional Naver-Stokes equations with standard $k-{\varepsilon}$ turbulence model and SIMPLE algorithm. Using a commercial code, PHOENICS, pressure and flow fields in TCV are calculated with different inlet and outlet diameters of the cylinder hole for cold and hot water passages.

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HRT-mediated Turnip crinkle virus Resistance in Arabidopsis

  • Park, Jeong-Mee;Daniel F. Klessig
    • The Plant Pathology Journal
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    • 제19권1호
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    • pp.19-23
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    • 2003
  • Turnip crinkle vims (TCV) inoculation onto resistant Arabidopsis ecotype Dijon(Di-17) leads to a hypersensitive response (HR) on the inoculated leaves. A dominant gene, HRT, which confers an HR to TCV, has been cloned from Di-17 plants by map-based cloning. HRT is a LZ-NBS-LRR class resistance gene and it belongs to a small gene family that includes RPP8, which confers resistance to Peronospora parasitica Emco5. Outside of the LRR region, HRT and RPP8 proteins share 98% amino acid identity while their LRR regions are less conserved (87% identity). HRT-transformed Arabidopsis plants developed an HR but generally remained susceptible to TCV due to a dominant RRT allele, which is not compatible with resistance. However, several transgenic plants that over-expressed HRT much higher than Di-l7 showed micro-HR or no HR when inoculated with TCV and were resistant to infection. Both the HR and resistance are dependent on salicylic acid but independent of NPRI, ethylene, or jasmonic acid. Arabidopsis plants containing both TCV coat protein gene and HRT developed massive necrosis and death in seedlings, indicating that the TCV coat protein is an avirulence factor detected by the HRT.

압력 평형식 온도조절 밸브 내부 유동 특성에 대한 수치적 연구 (A Numerical Study on the Flow Characteristics of Temperature Control Valve by Pressure Compensation)

  • 황정훈;김태안;김윤제
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
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    • pp.448-453
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    • 2005
  • Temperature Control Valve (TCV) is one of the useful temperature control devices, which is used to control constant temperature of working fluid in power and chemical plants and domestic water supply systems. TCV is composed of body, cylinder and piston, and the body shape has a symmetrical H-type. In general, it has several inlet and outlet holes, and its shape is like as tubular sleeve. The piston has three rings two rings of the end of piston have the function of controlling inlet flow rate with hot and cold working fluids, the center ring has the function of preventing hot and cold water from intermixing. Consequently, the shapes of piston and cylinder are the main design parameters in the performance of TCV. In this study, numerical analyses were carried out with two different piston and cylinder shapes to investigate the functions as a temperature control valve and the flow characteristics according to piston opening grade in TCV. Using a commercial code, FLUENT, velocity and pressure fields in TCV are obtained under steady, standard $k -{\epsilon}$ turbulence model and no-slip condition.

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압력 평형식 온도 조절 밸브의 유동특성 연구 (A study on the flow charateristics of temperature control valve by pressure compensation)

  • 김태안;김윤제
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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    • pp.419-424
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    • 2001
  • TCV(Temperature control valve by pressure compensation) controls temperature constantly, when it is sending steam or high temperature water to heating device of heat exchanger. For designing TCV, the ratio of piston and hole diameters is one of the important design parameters. Numerical analysis is carried out to elucidate the flow characteristics in the TCV with different port areas of cold and hot waters, using the k-$\epsilon$ turbulence model and Cartesian cut-cell method. Numerical results show that the exit flow rate is mainly affected by pressure distribution in the piston.

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이색 PIV를 이용한 5밸브 가솔린 엔진의 흡입 유동 해석 (A Study on Analysis of Intake Flow in a 5-valves Gasoline Engine by using a Two Color PIV System)

  • 우영완;박상찬;이기형;이창식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.933-938
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    • 2001
  • A 5-valve(intake 3-valve) engine has been developed to increase engine performance. These vehicles have a high power caused by the decrease of inertia mass of an intake valve and the increase of intake effective area. In this study, velocity profiles at near intake valves were inspected by using a two-color PIV and laser sheet method with tumble control valve(TCV). In addition, steady flow tests were performed to quantify tumble ratio on flow-fields generated with a TCV. These experimental results show that the tendency of the tunble ratio in intake 3-valve engine is different from the one in intake 2-valve engine. From this results, the intake flow characteristics around intake valves were made clear.

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300MW IGCC 가스화플랜트의 가스화 성능 및 Slag System 용량 예측 (Estimation of Gasification Performance and Slag System Capacity for 300MW IGCC Plant)

  • 구자형;백민수;유정석;김봉근;김유석;이황직
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.234-237
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    • 2008
  • 분류층 가스화기에서 가스화기 운전 온도는 슬래그의 원활한 배출과 가스화기 성능 등에 영향을 미친다. 가스화기 운전온도는 또한, 석탄 및 산소 소비량에도 영향을 미쳐 궁극적으로는 가스화 플랜트의 주요 설비 용량을 결정하는 주요 요인중의 하나이다. 가스화기 운전 온도가 일정수준 이상으로 증가할 경우 냉가스 효율이 저하되고 가스화 성능에 약 영향을 미친다. 본 논문에서는 Coal 및 Flux 공급장치, 슬래그 배출장치 당의 구성을 설명하고 Flux 투입량에 따른 슬래그 Tcv, 가스화기 성능 등을 예측하였다. 또한, 300MW IGCC 실증 가스화플랜트 엔지니어링을 위한 예비단계로 석회석 투입에 따른 Flux 공급장치를 포함한 Feeding 설비 용량, 슬래그처리설비 용량, 가스화기 내부 및 출구 적정온도를 예측하였다.

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The coat protein of Turnip crinkle virus is required a full-length to maintain suppressing activity to RNA silencing but no relation with eliciting resistance by N-terminal region in Arabidopsis.

  • Park, Chang-Won;Feng Qu;Tao Ren;T. Jack Morris
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.76.1-76
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    • 2003
  • The coat protein (CP) of Turnip crinkle virus (TCV) is organized into 3 distinct domains, R domain (RNA-binding) connected by an arm, 5 domain and P domain. We have previously shown that the CP of TCV strongly suppresses RNA silencing, and have mapped N-terminal R domain of which is also the elicitor of resistance response in the Arabidopsis ecotype Di-17 carrying the HRT resistance gene. In order to map the region in the TCV CP that is responsible for silencing suppression, a series of CP mutants were constructed, transformed into Agrobacterium, coinfiltrated either with HC-Pro (the helper component proteinase of tobacco etch potyvirus) known as a suppressor of PTGS or GFP constructs into leaves of Nicotiana benthmiana expressing GFP transgenically. In the presence of HC-Pro, all CP mutants were well protected, accumulating mutant CP mRNAs and their proteins even 5 days post-infiltration (DPI). In the presence of GFP, some mutant constructs which showed the accumulation of CP mutants and GFP mRNAs at early stage but eventually degraded at 5 DPI. Only a mutant which carrying 4 amino acid deletion of R domain was tolerable to maintain suppressing activity, suggesting that the suppressing activity is not directly related with the eliciting activity. A transient assay also revealed that the mutants synthesized their proteins, suggesting that a full length of CP sequences and its intact structure are required to stabilize CP, which suppresses the RNA silencing.

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잔대 종자 펠렛처리가 종자 발아에 미치는 영향 (Effect of Pelleting Treatment on Seed Germination in Adenophora triphylla)

  • 임동현;남주희;김종혁;이민주;노일래
    • 한국약용작물학회지
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    • 제28권2호
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    • pp.128-135
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    • 2020
  • Background: Sowing seeds of Adenophora triphylla is known to be difficult owing to their small size and irregular seed shape. Therefore, this study was conducted to develop a seed pelleting technique to save labor during sowing. Methods and Results: To identify the optimal germination temperature for A. triphylla seeds, the temperature range was set from 17℃ to 32℃. Germination surveys were conducted in plastic greenhouse conditions in March, April, and May to determine the appropriate sowing time. The optimal germination temperature for A. triphylla seeds was 29℃ and May was the optimal sowing time in plastic greenhouse conditions. Covering materials for seed pelleting used talc (T), kaolin (K), calcium carbonate (C), and vermiculite (V). The pellet binder used agar (A), pectin, xanthan gum, polyvinyl alcohol (PVA), and sodium alginate (S). The best suited treatment mixture were the best suited in kaolin / calcium carbonate / vermiculite (KCV), talc / calcium carbonate / vermiculite (TCV) mixture treatment for covering material, and sodium alginate (S), agar (A) as pellet binder, respectively. The germination rate was the best in TCV mixed with S. Conclusion: The mixture of TCV (2 : 1 : 3) + 1.5% S (TCVS), was found to be the best pelleting materials for A. triphylla seeds, and seed pelleting can be labor-saving during sowing.

V2O3와 CaO의 농도에 따른 5-성분계 석유코크스 슬래그의 점도 변화 (Effect of V2O3 and CaO Concentrations on the Viscosity of 5-Component Petcoke Slag)

  • 양윤정;오명숙
    • 공업화학
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    • 제31권6호
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    • pp.688-696
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    • 2020
  • 가스화 공정에서 원료 회분의 연속적인 제거를 위해 회분 성분에 따른 점도 거동뿐만 아니라, 온도가 낮아지면서 형성되는 결정체가 점도에 미치는 영향이 연구되어야 한다. 본 연구에서는 석유코크스 슬래그의 주성분 중 CaO와 V2O3 성분의 변화에 따른 슬래그의 점도 거동과 결정 분석을 통해 이 두 성분이 석유코크스 슬래그 점도에 미치는 영향을 조사하였다. 각각의 함유량을 변화시키면서 약 1600 ℃부터 약 1100 ℃까지 온도를 낮추며 점도를 측정하였고, 냉각된 시료의 결정상이 분석되었다. 측정된 시료는 대부분 결정형 점도 거동을 보여주었다. V2O3의 농도가 증가할수록 점도는 유리형에서 결정형으로 변화하였고, Tcv도 증가하는 경향을 보여주었다. CaO의 경우 농도가 증가할수록 낮은 점도와 낮은 Tcv를 보여주었다. 기준 시료를 포함한 모든 시료의 상, 중, 하부에서 다른 결정을 볼 수 있었다. 상, 중부에는 anorthite와 Ca-V 상이 관찰되었으면 하부에서는 주로 V2O3 결정과 anorthite이 관찰되었다. 슬래그의 바나듐은 Ca-V상, V-Fe, 용융 슬래그 상을 형성한다. 융점이 낮은 Ca-V 상은 점도를 낮추는데 기여하는 것으로 보인다.

DNA Damage Triggers the Activation of Immune Response to Viral Pathogens via Salicylic Acid in Plants

  • Hwi-Won Jeong;Tae Ho Ryu;Hyo-Jeong Lee;Kook-Hyung Kim;Rae-Dong Jeong
    • The Plant Pathology Journal
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    • 제39권5호
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    • pp.449-465
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    • 2023
  • Plants are challenged by various pathogens throughout their lives, such as bacteria, viruses, fungi, and insects; consequently, they have evolved several defense mechanisms. In addition, plants have developed localized and systematic immune responses due to biotic and abiotic stress exposure. Animals are known to activate DNA damage responses (DDRs) and DNA damage sensor immune signals in response to stress, and the process is well studied in animal systems. However, the links between stress perception and immune response through DDRs remain largely unknown in plants. To determine whether DDRs induce plant resistance to pathogens, Arabidopsis plants were treated with bleomycin, a DNA damage-inducing agent, and the replication levels of viral pathogens and growth of bacterial pathogens were determined. We observed that DDR-mediated resistance was specifically activated against viral pathogens, including turnip crinkle virus (TCV). DDR increased the expression level of pathogenesis-related (PR) genes and the total salicylic acid (SA) content and promoted mitogen-activated protein kinase signaling cascades, including the WRKY signaling pathway in Arabidopsis. Transcriptome analysis further revealed that defense-and SA-related genes were upregulated by DDR. The atm-2atr-2 double mutants were susceptible to TCV, indicating that the main DDR signaling pathway sensors play an important role in plant immune responses. In conclusion, DDRs activated basal immune responses to viral pathogens.