• 한국항공우주학회지
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• 제37권7호
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• pp.678-684
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• 2009

GNSS 반송파 위상 측정치를 사용하는 정밀 측위 혹은 자세결정에서 미지정수의 결정이 반드시 필요하며 많은 연구가 진행되었다. 그러나 한번 구해진 미지정수는 위성 추적상태가 변화하지 않으면 상수로 계속 사용할 수 있으므로 미지정수 검색과정을 통하지 않고 이미 구해진 미지정수를 사용할 수 있다. 본 논문에서는 ARCE를 변형하여 한번 구해진 미지정수와 새로운 측정치를 이용하여 환경 변화에서도 미지정수를 재구성할 수 있는 미지정수 전파기법을 제안하였다. 초기 미지정수는 LAMBDA로 구하며 신뢰도 향상을 위하여 여러 epoch 동안 연속해서 비율검사를 통과한 미지정수를 사용한다. 한번 구해진 미지정수는 위성의 배치, 위성 신호의 단락 등의 변화에도 미지정수 검색기법을 통하지 않고 제안한 기법을 사용하여 계속 유지될 수 있다. 이로 인하여 미지정수 결정의 성공률이 향상되며 계산량이 감소되는 효과를 얻을 수 있다. 실제 측정치를 이용한 실험으로 제안한 방법은 효과적인 방법임을 확인하였다.

• 제어로봇시스템학회논문지
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• 제5권1호
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• pp.69-78
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• 1999

The attitude determination system is indispensable for navigation, guidance and control tasks. In order to construct this system some special products that use dual frequencies or have on receiver engine with multiple antennas are used. But they are so expensive. Thus there are still strong requirements for the conventional low cost single frequency off-the-shelf receiver. This paper will propose a new technique to resolve integer ambiguity with single frequency GPS receiver and will show the problems of the attitude applications in which low cost receiver are being used. Also, based on this new technique precise attitude determination is presented.

• 한국군사과학기술학회지
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• 제3권2호
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• pp.131-139
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• 2000

A design of CPS attitude determination system is described in this paper. The designed system is a low cost high precision 24 channel single frequency GPS(Global Positioning System) receiver which provides a precise absolute heading and pitch (or roll) as well as a position. It uses commercial chip-set and consists of two RF parts, two signal-tracking parts, a processor, memory parts and I/Os. In order to determine precise attitude, accurate carrier phase measurements and an efficient integer ambiguity resolution method are required. To meet these requirements, a PLL (Phase Locked Loops) is designed, and an algorithm called ARCE (Ambiguity Resolution with Constraint Equation) is adopted. The hardware and software structure of the system will be described, and the performance evaluated under various conditions will be presented. The test results will promise that more reliable navigation system be possible because the system provides all navigational information such as position, velocity, time and attitude.

• 제어로봇시스템학회논문지
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• 제7권12호
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• pp.1036-1043
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• 2001

It is well-known that positioning accuracy can be improved by the use of carrier phase of GPS up to the centimeter level. In order to obtain good accuracy, we need to know integer ambiguity in the carrier phase accurately. In this paper, we propose a fast ambiguity determination method(FADM) which combines Kalman filtering and the search method, and show the improvement of the positioning performance by static and kinematic simulation compared with known methods such as Kalman filtering, LSAST (Least Squares Ambiguity Search Technique), ARCE(Ambiguity Resolution with Constratint Equation), LLL(Lenstra, Lenstra, and Lovasz) algorithms.

• BMB Reports
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• 제39권4호
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• pp.355-360
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• 2006

To gain a better understanding on the function of the potato Solanum tuberosum Multiprotein Bridging Factor 1 protein (StMBF1) its interaction with the TATA box binding protein (TBP) was demonstrated. In addition we reported that StMBF1 rescues the yeast mbf1 mutant phenotype, indicating its role as a plant co-activator. These data reinforce the hypothesis that MBF1 function is also conserved among non closely related plant species. In addition, measurement of StMBF1 protein level by Western blot using anti-StMBF1 antibodies indicated that the protein level increased upon $H_2O_2$ and heat shock treatments. However, the potato $\beta$-1,3-glucanase protein level was not changed under the same experimental conditions. These data indicate that StMBF1 participates in the cell stress response against oxidative stress allowing us to suggest that MBF1 genes from different plant groups may share similar functions.

• Molecules and Cells
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• 제19권3호
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• pp.418-427
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• 2005

When inoculated into sensitive tobacco Xanthi-nn plants, the crucifer and garlic-infecting Tobacco mosaic virus (TMV-Cg) induces local necrotic lesions that resemble those seen in the hypersensitive response (HR) of resistant tobacco plants. However, unlike these, tobacco Xanthi-nn plants do not become resistant to infection and the virus spreads systemically causing a severe disease characterized by necrotic lesions throughout the plant. To identify the viral protein that elicits this necrotic response, we used a set of hybrid viruses constructed by combination of TMV-Cg and the tobacco mosaic virus strain U1 (TMV-U1). In this study we present evidence that the coat protein of TMV-Cg (CPCg) is the elicitor of the necrotic response in tobacco Xanthi-nn plants. Local and systemic necrotic lesions induced by TMV-Cg and by the hybrid U1-CPCg -that carries CPCg in a TMV-U1 context- are characterized by cell death and by the presence of autoflorescent phenolic compounds and $H_2O_2$, just like the HR lesions. In addition, defense-related genes and detoxifying genes are induced in tobacco Xanthi-nn plants after TMV-Cg and U1-CPCg inoculation. We postulate that in our system, CPCg is recognized by sensitive tobacco plants that mount an incomplete defense response. We call this an HR-like since it is not enough to induce plant resistance.