• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.2
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• pp.528-544
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• 2015

Base Station Cooperation (BSC) has been a promising technique for combating the Inter-Cell Interference (ICI) by exchanging information through a high-speed optical fiber back-haul to increase the diversity gain. In this paper, we propose a novel pilot symbol assisted data fusion scheme for distributed Uplink BSC (UBSC) based on Differential Evolution (DE) algorithm. Furthermore, the proposed scheme exploits the pre-defined pilot symbols as the sample of transmitted symbols to constitute a sub-optimal Weight Calculation (WC) model. To circumvent the non-linear programming problem of the proposed sub-optimal model, DE algorithm is employed for searching the proper fusion weights. Compared with the existing equal weights based soft combining scheme, the proposed scheme can adaptively adjust the fusion weights according to the accuracy of cooperative information, which remains the relatively low computational complexity and back-haul traffic. Performance analysis and simulation results show that, the proposed scheme can significantly improve the system performance with the pilot settings of the existing standards.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1A
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• pp.114-121
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• 2000

The problem of an input-buffered switch is the HOL(head-of-line) blocking which limits the maximum throughput but it is easy to implement in hardware. However, HOL blocking can be eliminated using aVOQ(virtual-output-queueing) technique. 0 this paper, we propose a new cell-scheduling algorithm for aninput-buffered ATM switch. The proposed algorithm, called PPIM(Probabilistic Parallel Iterative Matching), imposesa weight to every request based on the reserved bandwidth. It is shown that the input-buffered ATM switch withthe proposed PPIM algorithm not only provides high throughput and low delay but it also reduces the jitter,compared with the existing WPIM(Weighted PIM).

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.7
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• pp.25-35
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• 2002

In this study, the effect of DEM (Digital Elevation Model) resolution (15m, 30m, 50m, 70m, 100m, 200m, 300m) on the hydrological simulation was examined using the BASINS (Better Assessment Science Integrating point and Nonpoint Source) for the Heukcheon watershed (303.3 ㎢) data from 1998 to 1999. Generally, as the cell size of DEM increased, topographical changes were observed as the original range of elevation decreased. The processing time of watershed delineation and river network needed more time and effort on smaller cell size of DEM. The larger DEM demonstrated had some errors in the junction of river network which might affect on the simulation of water quantity and quality. The area weighted average watershed slope became milder but the length weighted average channel slope became steeper as the DEM size increased. DEM resolution affected substantially on the topographical parameter but less on the hydrological simulation. Considering processing time and accuracy on hydrological simulation, DEM grid size of 100m is recommended for this range of watershed size.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.4
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• pp.348-356
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• 2014

To understand the relationship between road-traffic noise and urban components such as population, building, road-traffic and land-use, the city of Cheongju that already has road-traffic noise maps of daytime and nighttime was selected for this study. The whole area of the city is divided into square cells of a uniform size and for each cell, the urban components are estimated. A spatial representative noise level for each cell is determined by averaging out population-weighted facade noise levels for noise exposure population within the cell during nighttime. The relationship between the representative noise level and the urban components is statistically modeled at the cell level. Specially, we introduce a spatial auto regressive model and a spatial error model that turns out to explain above 85 % of the noise level. These findings and modeling methods can be used as a preliminary tool for environmental planning and urban design in modern cities in consideration of noise exposure.

• The Transactions of the Korea Information Processing Society
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• v.1 no.4
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• pp.469-478
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• 1994

In this paper, a high speed, high resolution information processing digital- analog converter was designed for high definition color graphic, digital image signal processing, HDTV. For high speed operation, matrix type current cell array, latch which is not use pipelined, and two dimensional structure decoder using transmission gate were designed. It is adopted to fast-conversion, low-power implementation and exhibited high performance at linearity and accuracy. To reduce silicon area and to maintain resolution, current cell array composed of weighted and non-weighted current cells. In this paper, deglitching current cell design for high accuracy, new switching algorithm assert to reduce switching error. It's This circuit dissipates 130W with a 5-V power supply, and operate above 100MHz with 10 bit resolution.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.12
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• pp.2725-2730
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• 2012

In this paper, for improving the H.264/AVC hardware performance, we propose an inter predictor hardware design using a multi reference frame selector and an implicit weighted predictor. previous reference frame are reused for Low Memory Bandwidth. The size of the reference memory in the predictor was reduced by about 46% and the external memory access rate was reduced by about 24% compared with the one in the reference software JM16.0. We designed the proposed system with Verilog-HDL and synthesized inter predictor circuit using the Magnachip 0.18um CMOS standard cell library. The synthesis result shows that the gate count is about 2,061k and the design can run at 91MHz.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.51-58
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• 2015

Ethanol has long been implicated in triggering apoptotic neurodegeneration. Alcohol also may indirectly harm the fetus by imparing the mother's physiology. We examined the effects of ethanol on immature brain of mice. Three-weeks-old female ICR strain mice daily intraperitoneally injected with ethanol at the concentration of 4 and 20% in saline for 0, 6, and 24 hours and 1 and 4 weeks. The mice were weighted and sacrificed, and the brains were ectomized for the present histological, immunohistochemical and TUNEL assays. Based on the histologic hematoxylin and eosin stain, immunohistochemical expression of glutamate receptor protein and neuronal cell adhesion molecule (NCAM) were evaluated. The cerebral cortex of the ethanol-treated group showed few typical symptoms of apoptosis such as chromosome condensation and disintegration of the cell bodies. TUNEL staining revealed DNA fragmentation in the 6 and 24 hours. This results demonstrated that acute ethanol administration causes neuronal cell death. I found that either glutamate receptor inhibition or activation could induce cerebellar degeneration as ethanol effect. Neuronal death also can be induced by excess activity of certain neurotransmitter, including glutamate. Neurons must establish cell-to-cell contact during growth and development in order to survive, migrate to their final destination, and develop appropriate connections with neighboring cell. Purkinje cell in cerebellar are especially vulnerable to the cell death and degeneration. After ethanol treatment in cerebellar, NCAM had decreased by 4 weeks. This result suggest that apoptosis seems to be involved in the slow elimination of neuron and cerebellar degeneration.

• Transactions on Electrical and Electronic Materials
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• v.10 no.2
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• pp.44-48
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• 2009

A simulation study of a 10-bit two-stage DAC was done by using a conventional current switch cell. The DAC adopts the segmented architecture in order to reduce the circuit complexity and the die area. The 10-bit CMOS DAC was designed in 2 blocks, a unary cell matrix for 6 MSBs and a binary weighted array for 4 LSBs, for fabrication in a 0.35-${\mu}m$ CMOS process. To cancel the accumulation of errors in each current cell, a symmetrical switching sequence is applied in the unary cell matrix for 6 MSBs. To ensure high-speed operation, a decoding circuit with one stage latch and a cascode current source were developed. Simulations show that the maximum power consumption of the 10-bit DAC is 74 mW with a sampling frequency of 100 MHz.

• Journal of Korean Neurosurgical Society
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• v.49 no.1
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• pp.71-74
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• 2011

A 34-year-old female patient was presented with leg and hip pain for 6 months as well as voiding difficulty for 1 year. Magnetic resonance imaging revealed a well-demarcated mass lesion at L2-3. The mass was hypo-intense on T1- and T2-weighted images with homogeneous gadolinium enhancement. Surgery was performed with the presumptive diagnosis of intradural extramedullary meningioma. Complete tumor removal was possible due to lack of dural adhesion of the tumor. Histologic diagnosis was clear cell meningioma, a rare and newly included World Health Organization classification of meningioma usually affecting younger patients. During postoperative 2 years, the patient has shown no evidence of recurrence. We report a rare case of cauda equina clear cell meningioma without any dural attachment.

• Journal of computational fluids engineering
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• v.11 no.4 s.35
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• pp.39-47
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• 2006

In this paper, the authors developed a multidimensional interpolation method inside a finite volume cell in the computation of high-order accurate numerical flux such as the fifth order WEND (weighted essentially non-oscillatory) scheme. This numerical method starts from a simple Taylor series expansion in a proper spatial order of accuracy, and the WEND filter is used for the reconstruction of sharp nonlinear waves like shocks in the compressible flow. Two kinds of interpolations are developed: one is for the cell-averaged values of conservative variables divided in one mother cell (Type 1), and the other is for the vertex values in the individual cells (Type 2). The result of the present study can be directly used to the cell refinement as well as the convective flux between finer and coarser cells in the Cartesian adaptive grid system (Type 1) and to the post-processing as well as the viscous flux in the Navier-Stokes equations on any types of structured and unstructured grids (Type 2).