• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.4
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• pp.137-143
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• 2002

Because Block Pulse functions are used in a variety of fields such as the analysis and controller design of systems, it is necessary to find the more exact value of the Block Pulse series coefficients. This paper presents a method for the state estimation of the time-invariant linear systems via the improved estimation method for the Block Pulse coefficients by using the Simpson's rule. The proposed method using the Simpson's rule improve the accuracy of the Block Pulse coefficients.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.399-406
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• 1996

This paper presents a method of hierarchical state estimation of the time-varying linear systems via Block-pulse function(BPF). When we estimate the state of the systems where noise is considered, it is very difficult to obtain the solutions because minimum error variance matrix having a form of matrix nonlinear differential equations is included in the filter gain calculation. Therefore, hierarchical approach is adapted to transpose matrix nonlinear differential equations to a sum of low order state space equation from and Block-pulse functions are used for solving each low order state space equation in the form of simple and recursive algebraic equation. We believe that presented methods are very attractive nd proper for state estimation of time-varying linear systems on account of its simplicity and computational convenience. (author). 13 refs., 10 figs.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.53 no.4
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• pp.175-182
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• 2004

This paper presents a new method for finding the Block Pulse series coefficients, deriving the Block Pulse integration operational matrices and generalizing the integration operational matrices which are necessary for the control fields using the Block Pulse functions. In order to apply the Block Pulse function technique to the problems of state estimation or parameter identification more efficiently, it is necessary to find the more exact value of the Block Pulse series coefficients and integral operational matrices. This paper presents the method for improving the accuracy of the Block Pulse series coefficients and derives generalized integration operational matrix and applied the matrix to the analysis of linear time-invariant system.

• Macromolecular Research
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• v.10 no.6
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• pp.311-317
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• 2002

The quantitative analysis of polymer micelles consisting of amphiphilic block copolymers was carried out by small-angle neutron scattering (SANS). The block copolymers, made of poly(2-ethoxyethyl vinyl ether-b-2-hydroxyethyl vinyl ether)(poly(EOVE-b-HOVE)), exhibited a sharp morphological transition from a homogeneous solution to a micelle structure with increasing temperature. This transition is accompanied by a formation of spherical domains of poly(EOVE) with a radius around 200 $\AA$. The variations of the size and its distribution of the domains were investigated as a function of polymer concentration and temperature. The validity of SANS analysis, including the wavelength- and incident-beam-smearing effects of the SANS instrument, was examined with a pre-calibrated polystyrene latex.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.9
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• pp.1049-1059
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• 2011

This study investigates the current state of companies that manufacture and sell outdoor wear. A survey was conducted to identify what problems they had and what aspects they needed to supplement through a comparison and analysis of their block patterns. Companies that manufactured outdoor wear and those that sold them were separately surveyed to understand their current state. The manufactures included 4 companies and 14 sellers. The survey used interviews to cover the areas of target consumers, development patterns, production lines, body size, nominal size, production size, and functional materials for each item, and aspects that need improvement. The survey period was from September $3^{rd}$ to $10^{th}$ 2008. There were three block patterns for jackets, T-shirts, and pants. The investigator collected the patterns used by three outdoor clothing manu-facturers for comparison and assessment. As a result, the mean age of the target consumers set by the outdoor clothing manufacturers and sellers was 25.3-50.7 and 29.2-42.5, respectively, which shows that the outdoor clothing had a wider distribution of target consumers than the sellers. It is imperative for them to segment and differentiate the target consumers and concepts. The basic body measurements the companies used to draw the upper and lower garment patterns were the bust circumference for the upper garment patterns and the waist circumference for the lower garment patterns. The basic nominal size was 95 for the upper garment and 70 for the lower garment. Also analyzed were the block patterns according to the items to understand the pattern characteristics of each of the companies. There were a total of 35, 36, and 30 items for the jackets, T-shirts, and pants, respectively, to measure size. The items were then compared with one another in mean and standard deviation. The analysis indicate that the block patterns were not fit for women in their twenties or thirties to wear and required revisions in the length of the upper garment, the height of sleeve cap, bust circumference, hip length, and pant length.

• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.49-52
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• 2013

An experiment to investigate the natural circulation of a cryogen has been performed. The study is motivated mainly by our recent development of cryogenic cooling system for prototype superconducting cyclotron without any circulating pump. In the natural circulation loop system, a cooling channel is attached on the outer surface of the aluminium block and the liquid nitrogen passes through inside of the channel to cool the block indirectly. A cryocooler as a heat sink is located at the top to re-condense cryogenic vapor coming from the aluminium block in which electrical heater is installed as a heat source. The main dimensions are determined using the relevant analysis and the natural circulation loop is successfully fabricated. The temperature distributions in the loop are measured during initial cool-down process and in steady state, from which the modified Grashof numbers are calculated and compared with the existing correlation estimated with one-dimensional analysis for steady state flow.

• Journal of the Korea Society of Computer and Information
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• v.15 no.1
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• pp.91-102
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• 2010

It is very difficult that a previous surveillance system and vehicle detection system find objects on a limited and unstable illumination condition. This paper proposes a robust method of adaptively updating a reference background image for solving problems that are generated by the unstable illumination. The first input image is set up as the reference background image, and is divided into three block categories according to an edge component. Then a block state analysis, which uses a rate of change of the brightness, a stability, a color information, and an edge component on each block, is applied to the input image. On the reference background image, neighbourhood blocks having the same state of a updated block are merged as a block. The proposed method can generate a robust reference background image because it distinguishes a moving object area from an unstable illumination. The proposed method very efficiently updates the reference background image from the point of view of the management and the processing time. In order to demonstrate the superiority of the proposed stable manner in situation that an illumination quickly changes.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.6
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• pp.172-182
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• 2003

In this study, the back analysis was performed by means of stereo-net, plane failure and block failure method to collapsed fields among the rock slopes designed by standardized criterion, and the internal frictions from the back analysis were compared with those used to reinforcement design. It was concluded that in the result of the analysis by means of stereo net, plain failure and block failure methods, the internal frictions used to re-design of collapsed slope underestimated 10$^{\circ}$, 5$^{\circ}$ and 10$^{\circ}$ in average. At present, the internal friction on the design is used the experience value according to the state of weathering, but internal friction angle by the back analysis on collapsed slope with various methods were more reliable values than those from the present method. And it was concluded that re-design was made extravagantly because the internal friction used to re-design for reinforcement of the collapsed slope was less than back analysis.

• Proceedings of the KIEE Conference
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• 1997.07b
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• pp.581-583
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• 1997

For the last two decades, many researchers have interests in orthogonal functions by reason of its applicability on linear system analysis. But they only used integral operation matrix of orthogonal functions to solve the state space equations. Thus, this paper present some new result of differential operation of block-pulse functions from a numerical point of view.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.3
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• pp.55-67
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• 1993

In this study, the thermal behavior characteristics of the cylinder block of a small 3-cylinder, 4-stroke gasoline engine were analyzed, using the 3-dimensional finite element method. Before numerical analyses were conducted, the performance test and the heat transfer experiment of the engine were carried out in order to prepare the input data for the computations. Engine cycle simulation was performed to obtain the heat transfer coefficient and the temperature of the gas and the mean heat transfer coefficient of coolant. Temperature fields as a result of steady-state heat transfer were obtained and compared with experimental results measured at specific points of the inner and the outer walls of the cylinder block. The thermal stress and deformation characteristics resulting from the nonuniform temperature distributions of the block were investigated. The effects of the thermal behaviors of the cylinder block on the engine operations and the unfavourable aspects of excessive thermal loading were examined on the basis of the calculated results.