• The Korean Journal of Pain
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• 제8권1호
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• pp.55-59
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• 1995

Stellate ganglion block (SGB) is applicated frequently to increase the blood flow and to reduce the pain in head, neck and upper extremity. The effects of SGB are able to be estimated by clinical signs and symptoms of Horner's syndrome, skin warmth, anhydrosis, etc. The effects are also estimated by sympathetic function and the blood flow. Blood flow velocities and pulsatility indices of common carotid,d axillary, brachial and radial artery were measured by Doppler flowmeter after SGB with 1% lidocaine at C6 level. Blood velocities of all arteries were increased and pulsatility indices of all arteries were decreased. This results suggest that SGB increase the blood flow of head and upper extremity and Doppler flowmeter is a good indicator of the effects of SGB.

• 동력기계공학회지
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• 제4권1호
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• pp.68-73
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• 2000

A mixed degree finite element solutions using hierarchical elements are investigated for convergences on a 2-D simple cases. Elements are generated block by block and each block is assigned an arbitrary solution degree. The numerical study showed that a well constructed blocks can increase the convergence and accuracy of finite element solutions. Also, it has been found that for higher order elements, the convergence trends can be deteriorated for smaller mesh sizes. A procedure for a variable fixed boundary condition has been included.

• 충청수학회지
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• 제31권1호
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• pp.137-149
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• 2018

In this paper, under the assumption of the symmetry point spread function, antireflective boundary conditions(AR-BCs) are considered in connection with the fast truncated Lagrange(FTL) method. The FTL method is proposed as an image restoration method for large-scale ill-conditioned BTTB(block Toeplitz with Toeplitz block) and BTHHTB(block Toeplitz-plus-Hankel matrix with Toeplitz-plus-Hankel blocks) linear systems([13, 17]). The implementation and efficiency of the FTL method in the AR-BCs are further illustrated. Especially, by employing the AR-BCs, both the continuity of the image and the continuity of its normal derivative are preserved at the boundary. A reconstructed image with less artifacts at the boundary is obtained as a result.

• International Journal of Naval Architecture and Ocean Engineering
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• 제8권4호
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• pp.398-408
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• 2016

Based on non-completely hybrid flow line scheduling of panel block in shipbuilding, several uncertain factors influencing the problem were analyzed in a real environment, and a nonlinear integer programming model was built for each sub-scheduling problem. To narrow the difference between theory and application, rolling horizon and rescheduling methods are proposed. Moreover, with respect to the uncertainty of processing time, arriving time and due time, we take the minimizing of the early and delayed delivery costs as the objective, and establish an evaluation with a global penalty function. Finally, numerical experiments and a simulation analysis were undertaken to demonstrate the effectiveness of the model and algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2252-2254
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• 2001

This paper proposes a algebraic parameter determination of MRAC (Model Reference Adaptive Control) controller using block Pulse functions and block Pulse function's differential operation. Generally, adaption is performed by solving differential equations which describe adaptive low for updating controller parameter. The proposes algorithm transforms differential equations into algebraic equation, which can be solved much more easily in a recursive manner. We believe that proposes methods are very attractive and proper for parameter estimation of MRAC controller on account of its simplicity and computational convergence.

• 전기학회논문지
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• 제67권9호
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• pp.1232-1238
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• 2018

This paper proposes methods for improving mass spectral resolution for a gas chromatograph mass spectrometer. The slope signs of the 1st and 2nd fitting functions for the ion signal block of each mass index are obtained, and the unnecessary element signals in the ion signal block are removed. The spectrum can be obtained by obtaining the second-order fitting function of the reconstructed ion signal block using only the effective ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed methods, computer simulations were performed using the actual ion signals obtained from the GC-MS system under development. Simulation results show that the proposed method is valid.

• 한국통신학회논문지
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• 제22권5호
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• pp.1107-1115
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• 1997

In this paper, we propose an error concealment method to recovre damaged block-based image coding schemes. Channel errors during transmission of image data such as bit errors or cell loss result in damaged image blocks in the reconstructed images. To recover damaged blocks is to estimate them using the correctly received or undamaged neighborhood information. In the proposed method, an overcomplete basis for a large block containing a damaged block at its center is introduced and damaged blocks are recovered by sequentially projecting the known neighborhood information onto the overcomplete basis function. Computer simulations show that the proposed algorithm outperforms the conventional method in subjectie recovery qualities as well as objective ones.

• 한국멀티미디어학회논문지
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• 제11권6호
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• pp.852-859
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• 2008

In this paper, we propose a dynamic keyed block encryption algorithm. Most existing encryption algorithms are designed such that the key is not changed. Therefore, they have a disadvantage that plaintext could be easily exposed by differential and linear cryptanalysis. In the proposed algorithm, several key generators are designed, and a key generator is attached to the encryption procedure. After performing the encryption procedure, ciphertext and the initial key generating values are transferred to the receiver's key generator for decryption. Through simulation, the proposed algorithm is verified to satisfy the requirements of real-time processing and proved to have a high strength. It can be applied to practical use.

• 한국컴퓨터정보학회논문지
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• 제24권6호
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• pp.73-80
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• 2019

In this paper, we propose an effective dynamic range compression (DRC) method of infrared images. A histogram of infrared images has narrow dynamic range compared to visible images. Hence, it is important to apply the effective DRC algorithm for high performance of an infrared image analysis. The proposed algorithm for high dynamic range divides an infrared image into the overlapped blocks and calculates Shannon's entropy of overlapped blocks. After that, we classify each block according to the value of entropy and apply adaptive histogram modification method each overlapped block. We make an intensity mapping function through result of the adaptive histogram modification method which is using standard-deviation and maximum value of histogram of classified blocks. Lastly, in order to reduce block artifact, we apply hanning window to the overlapped blocks. In experimental result, the proposed method showed better performance of dynamic range compression compared to previous algorithms.

• ETRI Journal
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• 제45권3호
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• pp.365-378
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• 2023

ARIA is a block cipher proposed by Kwon et al. at ICISC 2003 that is widely used as the national standard block cipher in the Republic of Korea. Herein, we identify some flaws in the quantum rebound attack on seven-round ARIA-DM proposed by Dou et al. and reveal that the limit of this attack is up to five rounds. Our revised attack applies to not only ARIA-DM but also ARIA-MMO and ARIA-MP among the PGV models, and it is valid for all ARIA key lengths. Furthermore, we present dedicated quantum rebound attacks on seven-round ARIA-Hirose and ARIA-MJH for the first time. These attacks are only valid for the 256-bit key length of ARIA because they are constructed using the degrees of freedom in the key schedule. All our attacks are faster than the generic quantum attack in the cost metric of the time-space tradeoff.