• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.12
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• pp.79-90
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• 2000

In this paper, a high-performance floating point unit, which is suitable for high-performance superscalar microprocessors and supports IEEE 754 standard, is designed. Floating-point arithmetic unit (AU) supports all denormalized number processing through hardware, while eliminating the additional delay time due to the denormalized number processing by proposing the proposed gradual underflow prediction (GUP) scheme. Contrary to the existing fixed-radix implementations, floating-point divide/square root unit adopts a new architecture which determines variable length quotient bits per cycle. The new architecture is superior to the SRT implementations in terms of performance and design complexity. Moreover, sophisticated exception prediction scheme enables precise exception to be implemented with ease on various superscalar microprocessors, and removes the stall cycles in division. Designed floating-point AU and divide/square root unit are integrated with and instruction decoder, register file, memory model and multiplier to form a floating-point unit, and its function and performance is verified.

• Korean Journal of Oriental Medicine
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• v.14 no.2
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• pp.113-119
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• 2008

In pulse diagnosis, floating pulse and sinking pulse are frequently used for diagnosis about where disease is located and how much severe they are. However, in what mechanism floating pulse and sinking pulse arise is not known well. There are two point of views on substantial of floating pulse and sinking pulse. The first one is the floating and sinking degrees is the expression on the depth of pulsation. And, the second one is floating and sinking pulse is based on the response of pulsation to the indent pressure on radial artery. In this paper, we discussed these two opinions in the view point of tonometric measurement. The process for diagnosis on floating pulse and sinking pulse is similar to the tonometric measurement for non invasive blood pressure or intraocular pressure. We modelled the degrees of depth of pulsation with different indent pressures for initial pulsation feeling and different slopes of indent pressure lines. From this modelling, we can confirm the effect of pulsation depth on P-H curve, that is, in the model where lower pulsation is assumed, the shift of optimal indent pressure to the right was observed. The response of pulse pressure to the indent pressure was tried to be modelled with the degrees of mean blood pressure. Consequently, we tried to model the phenomenon of floating and sinking pulse for the first. And, from this modelling, we can get abundant understanding on how floating and sinking pulse can be caused. In the further study, we want to prove the suitability of this tonometric measurement based modelling with various studies including ultrasound measurement for the depth of pulsation in different EMI subjects.

• The Journal of the Acoustical Society of Korea
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• v.16 no.1E
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• pp.41-48
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• 1997

The very purpose of subband codec is the attainment of data rate compression through the use of quantizer and optimum bit allocation for each decimated signal. Yet the question of floating-point quantization effects in subband codec has received scant attention. There has been no direct focus on the analysis of quantization errors, nor on design with quantization errors embedded explicitly in the criterion. This paper provides a rigorous theory for the modelling, analysis and optimum design of the general M-band subband codec in the presence of the floating-point quantization noise. The floating-point quantizers are embedded into the codec structure by its equivalent multiplicative noise model. We then decompose the analysis and synthesis subband filter banks of the codec into the polyphase form and construct an equivalent time-invariant structure to compute exact expression for the mean square quantization error in the reconstructed an equivalent time-invariant structure to compute exact expression for the mean square quantization error in the reconstructed output. The optimum design criteria of the subband codec is given to the design of the analysis/synthesis filter bank and the floating-point quantizer to minimize the output mean square error. Specific optimum design examples are developed with two types of filter of filter banks-orthonormal and biorthogonal filter bank, along with their perpormance analysis.

• Journal of Ocean Engineering and Technology
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• v.12 no.2 s.28
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• pp.121-129
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• 1998

A quantitative non-contact multi-point measurement system is proposed to the measurement of three-dimensional movement of floating vessels by using digital image processing. The instantaneous three-dimensional movement of a floating structure which is floating in a small water tank is measured by this system and its three-dimensional movement is reconstructed by the measurement results. The validity of this system is verified by position identification for spatially distributed known positional values of basic landmarks set for the camera calibration. It is expected that this system is applicable to the non-contact measurement for an unsteady physical phenomenon especially for the measurement of three-dimensional movement of floating vessels in the laboratory model test.

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.706-713
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• 2014

An enhanced 360-degree integral-floating three-dimensional display system using a hexagonal lens array and a hidden point removal operator is proposed. Only the visible points of the chosen three-dimensional point cloud model are detected by the hidden point removal operator for each rotating step of the anamorphic optics system, and elemental image arrays are generated for the detected visible points from the corresponding viewpoint. Each elemental image of the elemental image array is generated by a hexagonal grid, due to being captured through a hexagonal lens array. The hidden point removal operator eliminates the overlap problem of points in front and behind, and the hexagonal lens array captures the elemental image arrays with more accurate approximation, so in the end the quality of the displayed image is improved. In an experiment, an anamorphic-optics-system-based 360-degree integral-floating display with improved image quality is demonstrated.

• Journal of Power Electronics
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• v.17 no.3
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• pp.653-663
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• 2017

Multilevel active neutral-point-clamped (ANPC) converter combines the advantages of three-level ANPC converter and multilevel flying capacitor (FC) converter. However, multilevel ANPC converter often suffers from capacitor voltage balancing problems. In order to solve the capacitor voltage balancing problems for five-level ANPC converter, phase-shifted pulse width modulation (PS-PWM) is used, which generally provides natural voltage balancing ability. However, the natural voltage balancing ability depends on the load conditions and converter parameters. In order to eliminate voltage deviations under steady-state and dynamic conditions, the active voltage-balancing control (AVBC) methods of floating capacitors and dc-link capacitors based on PS-PWM are proposed. First, the neutral-point current is regulated to balance the neutral-point voltage by injecting zero-sequence voltage. After that, the duty cycles of the redundant switch combinations are adjusted to balance the floating-capacitor voltages by introducing moderating variables for each of the phases. Finally, the effectiveness of the proposed AVBC methods is verified by experimental results.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.11
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• pp.1137-1143
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• 2009

This paper presents the FPGA implementation of efficient algorithms for approximating exponential function based on floating point format data. The Taylor-Maclaurin expansion as a conventional approximation method becomes inefficient since high order expansion is required for the large number to satisfy the approximation error. A format converter is designed to convert fixed data format to floating data format, and then the real number is separated into two fields, an integer field and an exponent field to separately perform mathematic operations. A new assembly command is designed and added to previously developed command set to refer the math table. To test the proposed algorithm, assembly program has been developed. The program is downloaded into the Altera DSP KIT W/STRATIX II EP2S180N Board. Performances of the proposed method are compared with those of the Taylor-Maclaurin expansion.

• The Journal of Korean Medicine
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• v.29 no.5
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• pp.104-110
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• 2008

Objectives : The purpose of this study is to develop the method of selecting representative pulse wave. Methods : The pulse waves were acquired at the right and the left Guan point(關部) with 1420 people who were apparently healthy. The shape agreement of right and left pulse wave and the floating-sinking ratio were compared with three cases, which were the pulse height based method, the pulse area based method, and the pulse time based method. Results : In the point of the shape accordance, the pulse time based method was the best, and the pulse area based method was the worst. In the point of the floating-sinking ratio, the pulse height based method was the worst, and the pulse time based method was the best. Conclusions : So, the pulse time based method was recommended for selecting the representative pulse wave. This study compared the selection methods of representative pulse using the physiological characteristics of pulse wave. Further studies are required, because the representative pulse wave is the main factor of determining the shape and the floating-sinking characteristic of the pulse wave.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.4
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• pp.24-29
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• 1983

In this paper, a floating-point processor which satisfied the subset of the proposed IEEE standard has been designed and realized by TTL chips. This processor consists of a floating-point arithmetic unit and a control sequencer. AHPL has been used in the design of sequencer. The execution times for the arithmetic operations were measured and compared with other microprocessor. The results had shown faster operations compared to the Z-80 processor. Though this processor was built by TTL chips, it could be fabricated as a one-chip processor.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.98-100
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• 2005

DSPs used at motor control are usually fixed point processor. They need scaling because they cannot excute floating point calculation. Scaling for floating point calculation makes the DSP's speed down, complex coding and etc. Therefore the IQ math is adopted. IQ math makes the fixed point processor possible to calculate the floating point math. In addition, IQ math can reduce memory usage and be more faster than that without IQ math. It seems that IQ math is appropriate in motor position control. In comparison of the position calculation between the IQ math, math function and the sine table, the method using IQ math is superior than other methods.