• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.167-170
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• 2001

A low power pulse Doppler radar should integrate a large number of data to provide a required maximum detectable distance. Doppler filter needs a window that has good out-of-bard rejection level to maintain high dynamic range. From these facts, we can apply decimation and presumming to increase the speed of Doppler processing. This Paper investigates the efficiencies of several decimation methods and the loss of presumming. And I propose a method to increase processing speed but to maintain the maximum detectable distance.

• Korean Journal of Computational Design and Engineering
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• v.19 no.1
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• pp.61-67
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• 2014

This paper proposes a procedure enabling the extraction of view-dependent triangular approximations from a height map. In general, procedures to approximate a height map use tree hierarchies. These methods, however, have a limitation in terms of accuracy, because they depend on tree hierarchy than terrain features. To overcome the difficult, we apply the simplification method for triangular meshes to a height map. The proposed procedure maintains full decimation procedure to support multiresolution. The maintenance of decimation procedure results in creation of the groups (trees), each of which consists of vertices that can be merged into one vertex (root node). As the groups have tolerance which is determined by some tests, they support the generation of view-dependent arbitrary triangular meshes.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.201-205
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• 1997

With the recent advance of Web and its associated technologies, information sharing on distribute computing environments has gained a great amount of attention from many researchers in many application areas, such as medicine, engineering, and business. One basic requirement of distributed medical consultation systems is that geographically dispersed, disparate participants are allowed to exchange information readily with each other. Such software also needs to be supported on a broad range of computer platforms to increase the software's accessibility. In this paper, the development of world-wide-web based medical consultation system or radiology imaging is addressed to provide the platform independence and great accessibility. The system supports sharing of 3-dimensional objects. We use VRML (Virtual Reality Modeling Language), which is the de-facto standard in 3-D modeling on the Web. 3-D objects are reconstructed from CT or MRI volume data using a VRML format, which can be viewed and manipulated easily in Web-browsers with a VRML plug-in. A Marching cubes method is used in the transformation of scanned volume data set to polygonal surfaces of VRML. A decimation algorithm is adopted to reduce the number of meshes in the resulting VRML file. 3-D volume data are often very large-sized, and hence loading the data on PC level computers requires a significant reduction of the size of the data, while minimizing the loss of the original shape information. This is also important to decrease network delays. A prototype system has been implemented (http://netopia.snu.ac.kr/-cyber/). and several sessions of experiments are carried out.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.4
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• pp.10-15
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• 1983

In this paper effective methods of demodulation and equalization in a 9600 bps modem have been studied. To reduce the number of multiplications required per symbol in demodula-tion, the method of using a decimation filter is presented. In the equalizer the optimum step size and the steady state mean-squared error (MSE) are obtained from computer simulation results. The performance of the first-order carrier phase tracking loop is compared with that of the second-order loop when carrier frequency offset exists. In addition, the finite word length effects in the equalizer are studied.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.4
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• pp.185-191
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• 2002

In this paper, we propose a 3D object LOD(Level of Detail) modeling system that constructs a mesh from range images and generates the mesh of various LOD using the wavelet transform. In the initial mesh generation, we use the marching cube algorithm. We modify the original algorithm to apply it to construct the mesh from multiple range images efficiently. To get the base mesh we use the decimation algorithm which simplifies a mesh with preserving the topology Finally, when reconstructing new mesh which is similar to initial mesh we calculate the wavelet coefficients by using the wavelet transform. We solve the critical problem of wavelet-based methods - the surface crease problem (1) - by using the mesh simplification as the base mesh generation method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.2
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• pp.309-314
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• 2008

Analog-to-digital converters(ADCs) used in instrumentation and measurements often require high absolute accuracy, including excellent linearity and negligible dc offset. Incremental(integrating) data converters(IDCs) provide a solution for such measurement applications, as they retain most of the advantages of conventional $\Delta{\Sigma}$ converters, and yet they are capable of offset-free and accurate conversion. In this paper, a design technique for implementing multiplexed incremental data converters to convert narrow bandwidth AC signals over multi-channel is discussed. It incorporates the operation principle, topology, and digital decimation filter design. The theoretical results are verified by simulation results.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.11
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• pp.913-924
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• 1991

In this paper, we propose a motion estimation algorithm using hierarchical structure. The algorithm uses the image pyramids from the repetitive application of Gaussian filtering and decimation, and performs an inter-level displacement propagation in its motion estimation process. The motion estimation algorithm based on the hierarchical structure is shown to be very effective since this scheme utilizes the local imformation as well as the global imformation. The experimental results on the various data imdicate that compared to the Horn and Schunck's method, the proposed algorithm yields an accurate motion estimation with a fast convergence behaviour.

• The Journal of the Korea institute of electronic communication sciences
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• v.3 no.3
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• pp.165-169
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• 2008

Analog-to-Digital converters (ADCs) used in instrumentation and measurements often require high absolute accuracy, including excellent linearity and negligible dc offset. Incremental converters provide a solution for such measurement applications, as they retain most of the advantages of conventional ${\Delta}{\Sigma}$ converters, and yet they are capable of offset-free and accurate conversion. Most of the previous research on incremental converters was for single-channel and dc signal applications, where they can perform extremely accurate data conversion with more than 20-bit resolution. In this paper, a design technique for implementing multiplexed incremental data converters to convert narrow bandwidth ac signals is discussed. A design methodology to optimize the signal-to-quantization+thermal noise ratio of multiplexed IDC is presented. It incorporates the operation principle, topology, and digital decimation filter design. The theoretical results are verified by simulation results.

• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.1
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• pp.33-36
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• 2009

Incremental converters provide a solution for such measurement applications, as they retain most of the advantages of conventional ${\Delta}{\Sigma}$ converters, and yet they are capable of offset-free and accurate conversion. Most of the previous research on incremental converters was for single-channel and dc signal applications, where they can perform extremely accurate data conversion with more than 20-bit resolution. In this paper, a design technique for implementing multi-channel incremental data converters to convert narrow bandwidth ac signals is discussed. It incorporates the operation principle, topology, and digital decimation filter design. The theoretical results are verified by simulation results.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.11b
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• pp.47-52
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• 1999

The visualization of Moire or laser-scanned data has been explored by many researchers and has been an important issue on computer graphics research. In this paper, we present various techniques that handle tremendous amount of 3D range data which are generated by the ETRI- Moire Scanner. The techniques include constructing an efficient data structure, constructing triangle meshes and decimation and registration of multiple-view range images and textures.