• Title/Summary/Keyword: CAB

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Differential Expression of Arabidopsis Cab Promoters in Organs of Transformed Tobacco Plants (형질전환된 담배식물체의 기관에 따른 Arabidopsis Cab Promoter의 차별적 실험)

  • 홍순조
    • Journal of Plant Biology
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    • v.35 no.3
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    • pp.229-235
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    • 1992
  • Differential expression of the three chlorophyll afb binding (cab) protein gene (cabl, cab2, and cab3) promoters of Arabidopsis thaliana was studied in tobacco plants transformed with cab-CAT (chloramphenicol acetyltransferase) translational fusions. CAT activity was measured to monitor the activities of the cab promoters. The activity of cabi promoter was higher than the other two in transformed tobacco leaves and also in calli and shoots derived from the leaves. Their activities were organ-specific and were the lowest in roots, medium in stems, and the highest in leaves. The relative activity of cabi promoter in stems comparing to it activity in leaves was, however, much higher than the values of cab2 and cab3. When the cab promoter activity was expressed as CAT activity per unit chlorophyll instead of CAT activity per unit protein, the relative cab] promoter activity (stem/leaf) became almost unity. This result suggests that cab2 and cab3 show photosynthetic organ-specificity but cabl does not. Similar result was obtained in the differentiation process of stems and leaves from shoots derived from the transgenic tobacco leaves.leaves.

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Differential Activation of Arabidopsis Cab Promoters during Greening of Transgenic Tobacco Shoots (형질전환된 담배 어린 싹의 녹화과정 중 Arabidopsis Cab 프로모터의 활성 차이)

  • 이춘환
    • Journal of Plant Biology
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    • v.36 no.3
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    • pp.267-273
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    • 1993
  • Promoters of the chlorophyll a/b bidning protein genes, cab1, and cab2, of Arabidopsis thaliana were studied for their functions in differential expression during greening of etiolated shoots. The etiolated shoots were derived from leaves of transgenic tobacco plants with the cab-CAT (chloramphenicol acetyltransferase) translational fusions, and CAT activity was measured to monitor the activities of the cab promoters. Cab1 promoter activity increased rapidly and showed saturation after about 24 hours of greening, but that of cab2 increased with about 2 day-lag period and showed saturation after 6 days. Cab1 promoter activity was more sensitive to levulinic acid (LA) compared with cab2 activity. Cab2 promoter activity was inhibited more sensitively by chloramphynicol (CAP) than by inhibitors of Chl formation. Cab1 promoter activity was, however, inhibited less sensitively by CAP than by LA. The treatment of abscisic acid (ABA) did not block Chl synthesis so significantly as LA treatment did, and cab2 promoter activity was much less sensitive to ABA compared with that of cab1. These results suggest that cab1 expression is strongly related with Chl formation, possibly with $\delta$-aminolevulinic acid accumulation, and cab2 expression is suppressed more by the blockage of translation of Chl a-apoproteins than by the blockage of Chl a accumulation.

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A Study on the Optimal Design of Hydraulic Cab Tilting System by the Genetic Algorithm (유전자 알고리즘에 의한 전동 유압 CAB TILTING SYSTEM의 최적설계에 관한 연구)

  • 김수태;김진한;정상원;김규탁;이호길
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.10a
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    • pp.67-72
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    • 2004
  • Generally, the commercial truck has the hydraulic cab tilting system which absorb the vibrations and impacts of the cab. The cab tilting system is equipped for the maintenance and inspection of truck. And it is very important to help user's feeling of driving and convenience. But when the truck cab is tilted, existing model has serious problem of vibration. To satisfy customer's requirements for convenience, it is necessary to improve the hydraulic truck cab tilting system. In this study, the optimization of cab tilting system is carried out by using the G.A to reduce the vibration. The results show that the vibration is reduced and the mean velocity of tilting is improved. In conclusion the improved cab tilting system can be designed and the possibility of optimal design for cab tilting system by using the GA is testified.

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Design of Driver's Cab for KHST Power Car (한국형 고속전철 동력차 운전실 설계)

  • 염경안;강석택;박광복
    • Proceedings of the KSR Conference
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    • 1999.11a
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    • pp.139-145
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    • 1999
  • The design of driver's cab includes the structure of cab frame, the layout of driver's cab equipment and facilities, i.e. driver's desk, seat, windows, floor, interior equipment, cab partition etc. The concept applied to the detail design has to be based on the ergonomics to guarantee the safety, comfort, and easy operation for the driver. In the aspect of manufacture, one more factor 'modulization' has to be considered into the design of sub blocks for cost-down. The design has to be implemented in the space allocated for driver's cab, which space is directly determined by the cab frame, optimized for the layout of driver's cab. The design process and results of the driver's cab for KHST will be described in this paper.

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The Improvement of Cab Tilting system in Heavy Truck and the Development of Program for Automatic Design Parameter Selection (트럭 캡 틸팅 시스템의 성능 향상 및 설계 파라미터의 자동 선정 프로그램의 개발)

  • Park, Sung-Hwan;Lee, Jin-Kul
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.4
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    • pp.496-503
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    • 1999
  • In this paper, the improvement of cap tilting system in heavy truck and the development of program for automatic design are discussed. Cab tilting system takes some important roles in heavy truck, absorbing discomfort vibration from load, increasing repair efficiency and making sure of safety. Common manual cab tilting system cannot be easily tilt up in sloped road, giving difficulty to driver as cal tilting up/down. So recently hydraulic cab tilting system is in wide use. But some problem such as tilting up/down speed is not constant and sudden swing of cab has brought discredit from user. Therefore, this paper presents advanced cab tilting system which prevents sudden swing of cab and development of program for selecting design parameters automatically.

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Determination of Dynamic Parameters of Agricultural Tractor Cab-Suspension by Modal Analysis (모드 해석을 이용한 트랙터 캡-현가 장치의 동적 파라미터 결정에 관한 연구)

  • 조진상;김경욱;박홍제
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.8
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    • pp.216-223
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    • 1999
  • This study was intended to determine the inertia , damping and stiffness properties of the cab-suspension of agricultural tractors by applying the direct system identification method (DSIM). Since the rigid and elastic modes of the cab-suspension are not likely to be separated clearly, direct application of the DSIM may result in large computation error. To solve such a problem, a method of locating mass center of the cab were determined by assuming the behavior of the cab-suspension is a rigid body motion. The dynamic parameters of the cab-suspension were then determined by applying the DSIM with the known coordinates of the mass center. The constraints of spatial matrices of the cab-suspension also make the algorithm for the DSIM perform better. The values of dynamic parameters determined by this method agreed well with those determined by the experiment.

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Cryptanalysis of Two Block Ciphers based on Cellular Automata (셀룰러 오토마타 기반 블록 암호에 대한 안전성 분석)

  • Ryu, Han-Seong;Lee, Je-Sang;Lee, Chang-Hoon;Hong, Seok-Hie
    • Journal of Korea Multimedia Society
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    • v.11 no.8
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    • pp.1111-1120
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    • 2008
  • Cellular automata(CA) is often applied to design cryptosystems because it has good diffusion and local interaction effects. Recently, a 128-bit CA-based block cipher, called CAB1, and a 64-bit reversible CA-based block cipher, called CAB2, were proposed in KMMS'02 and CEC'04, respectively. In this paper, we introduce cryptanalytic results on CAB1 and CAB2. Firstly, we propose a differential attack on CAB1, which requires $2^{31.41}$ chosen plaintexts with about $2^{13.41}$ encryptions. Secondly, we show that CAB2 has a security of 184 bits using the statistical weakness. Note that the designers of CAB2 insist that it has a security of 224 bits. These are the first known cryptanalytic results on them.

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Study on compatibility of cellulose ester/poly(ethylene-co-isosorbide terephthalate) solution blends (셀룰로오스 에스터와 Poly(ethylene-co-isosorbide terephthalate) 용액 블렌드의 상용성에 관한 연구)

  • Kim, Yeon-Hee;Nam, Byeong-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.5
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    • pp.3351-3356
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    • 2014
  • Recently, Importance of studying based on biomass materials have increased due to the concern about plastic waste problems. Cellulose acetate butyrate (CAB) is a potential alternative to petroleum-based plastics because of its biodegradable property. Poly(ethylene-co-isosorbide terephthalate) (PEIT) is bio-based plastic, produced by isosorbide monomer. In this study, CAB/PEIT blends were prepared by solution blending to improve thermal stability of CAB. CAB and PEIT were dissolved in chloroform, and then precipitated in ethanol. To evaluate the compatibility of CAB/PEIT blends, the morphology and glass transition behaviors were analyzed by FE-SEM and DMA, respectively. TGA results revealed the improved thermal stabilities of the PEIT-rich and 50:50 compositions. No new or changed crystal structures were observed in the XRD result. Finally, CAB/PEIT solution blends showed good compatibility in overall compositions.

The Development of Exclusive Control Valve for Improving the Performance of Truck Cab Tilting System (트럭 캡 틸팅 시스템의 성능 향상을 위한 전용 제어 밸브의 개발)

  • Park, Sung-Hwan;Lee, Jin-Kul
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.3
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    • pp.90-98
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    • 2001
  • In this paper, the development of exclusive control valve for improving the performance of truck cab tilting system is discussed. Cab tilting system is implemented to the heavy truck for the convenience of driver. However when tilting up or down, sudden swing of cab has brought discredit on user. To improve this phenomena it is inevitable to use counter balance valve. But because of high pressure and low flow characteristic, general counter balance valve is unsuitable to cab tilting system. Therefore, this paper presents the developments of exclusive return pressure control valve which prevents sudden swing of cab and verify the validity of design through the computer simulation.

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