• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2C
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• pp.298-305
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• 2004

This paper presents an error compensation method for a fixed-width modified Booth multiplier that receives a W-bit input and produces a W-bit product. To efficiently compensate for the quantization error, Booth encoder outputs (not multiplier coefficients) are used for the generation of error compensation bias. The truncated bits are divided into two groups depending upon their effects on the quantization error. Then, different error compensation methods are applied to each group. By simulations, it is shown that quantization error can be reduced up to 50％ by the proposed error compensation method compared with the existing method with approximately the same hardware overhead in the bias generation circuit. It is also shown that the proposed method leads to up to 40％ reduction in area and power consumption of a multiplier compared with the ideal multiplier.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.819-827
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• 2019

Bragg reflection of water waves by three kinds of surface-piercing fixed structures with rectangular, cosinoidal and triangular shapes is studied. Boundary element method is used to analyze the wave scattering by these structures based on the linear wave theory. Results of reflection and transmission coefficients are validated by comparing with those available in literature. These structures with proper configurations are proved to be effective in attenuating waves by using Bragg reflection, and the triangular structures are found to be the best choices among the structures with same width and same area. Systematic calculations are then carried out for the triangular structures by varying the number, the draft, the width, the gap and the combination of width and gap of the structures to analyze their influences on the characteristics of Bragg reflection. The results are of reference values for design of the structures to attenuate waves based on the Bragg reflection.

• The International Journal of Costume Culture
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• v.4 no.3
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• pp.182-194
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• 2001

The main purpose is to study lines on different body types and to disguise any imperfections by using diverse princess lines. We separated festers body shapes into specific body types, A, H by applying both the direct and the indirect measurements. Following are the results of the study: 1. nose are the resulting illusion effects when the shoulder width of the princess line was fixed. In case of the armhole princess line, the illusion that the waist intervals were narrow or wide in A-line silhouette. In case the shoulder princess line, when the waist interval was narrow, it appeared to show narrow shoulder in A-line silhouette. While the wide waist interval shows the wide shoulder width in H-line silhouette. It regards body type H in the same light as H-line silhouette when the waist interval is narrow, it appeared to show narrow shoulder width in A-line silhouette. When the waist interval was wide, it appeared to give the narrow shoulder width. 2. When the princess lines waist width was fixed in order to study illusion effects of waist widths. Generally, for body type A, Whether the waist interval princess line is narrow or wide, the princess line is located comparatively wide, in A-line silhouette appeared to show relatively slender waist. For body type H, whether the waist interval is narrow or wide, the princess line us situated comparatively narrow interval, H-line silhouette appeared to show sum waist but the differences are not significant 3. The illusion of the hip were studied by fixating the width of the skirt and varying the locations of princess line and waist widths. For the location of both armhole and shoulder princess line in H and A-line silhouette, the narrow shoulder width and the waist appeared to show narrow hips. mile they are wide appeared to show wide hips. 4. With both waist and skirt width fuel, all two body types showed taller and slender postures when the princess line originated from the shoulder compare to the armhole.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.326-331
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• 2005

In this study, bearing response in single lap riveted joint is investigated by menas of single lap shear specimens with different types of adherend and fastener. Single lap shear specimen consists of adherend of SUS403 and carbon fabric/epoxy composite. Rivet of Avdel 2691 with 9.6mm diameter is used. Two types of fastener in single lap riveted joint are considered. One is a single lap shear specimen with single fastener, and the other is a single lap shear specimen with double fasteners. Especially, in case of single lap shear specimen with single fastener, the width of the specimen is varied as 2D, 3D, 4D, 6D at a fixed edge distance of 3D. Also the edge distance of the specimen is varied as 1.0D, 1.5D, 2.0D, 2.5D, 3.0D at a fixed width of 4D. In case of single lap shear specimen with double fasteners, two types of specimen are considered. One is a specimen with the width of 6D and edge distance of 3D. The other is a specimen with the width of 4D and edge distance of 2D. Here D designates the hole diameter for riveted joint.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.391-399
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• 2021

The conformal array sensor has different sub-array depending on different beam steering directions. According to the method to effective the sensor, the performance of the conformal array sensor can be different, where the sub-array selects an effective sensor. Also, due to the figure of the conformal array sensor, the figure of the sub-array can be different each other, which results in different performance on directivity index, beam width and etc. In this paper, two methods to select sub-array which is the criteria for each sensors position vector and directive vector were proposed. For two sub-array selection methods, the performance of the directivity index, horizontal and vertical beam width were compared with the average and variance. In addition, this comparison was conducted when the number of sensors was fixed. When the number of sensors was not fixed, the directional vector method mainly results in high performance, but the performance of vertical beam width was lower or equal. When the number of sensors was fixed, the performance of two methods is similar, but the performance of variance was deteriorated.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1255-1260
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• 2009

Microstrip interdigital filter is designed with the width and length of a resonator, the gap distance between resonators and the location of a tap. When designing filters, it is a benefit to design with few design parameters comparing to many design parameters. In this paper we design and implement two microstrip interdigital filters operating in the UWB(Ultra Wide-Band) frequency band, one using a fixed width of a resonator and the other using a different width of resonators. The test results of the implemented filters show that the low-band high filter with a fixed width has the insertion loss of 1.49dB, -10dB band width of 720MHz, -35.7dBattenuation at 4.8GHzand below -13dB of S11. The filter with a different width of resonators has the insertion loss of 1.6dB, -10dBbandwidth of 1.63GHz and below-8dBof S11.

• The Korean Journal of Ecology
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• v.12 no.3
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• pp.133-144
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• 1989

The morphology and flowering time of two Suaeda japonica populations from different habitats, the creek and the bank of the mudflat in Sorae, were surveyed. And standard transplantation and reciprocal transplantation were carried out to determine whether their characteristics were genetically fixed or not. Also soil sample of these habitats were analyzed. The amounts of loss on ignition, maximum field capacity, total nitrogen, exchangeable calcium and potassium, and soluble phosphorus were found to be significantly different between two habitats. Leaf thickness, leaf width, leaf length, stem height number of branches, and number of seeds were significantly different between plants of two populations. And flowering times of two populations did not overlap. According to the results of transplantation, leaf width, leaf thickness, and flowering times were the same as those at their original habitat. But the stem lenght, leaf lenght, number of branches and unmber of seeds were not. Therefore, the differences in the leaf length, leaf thickness, and flowering time seemed to bo genetically fixed. It were suggested that the creek bank populations of Suaeda japoinica were to be considered as different ecotypes.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.2
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• pp.199-205
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• 2011

This paper presents a QR decomposition processor by exploiting Givens rotation for the GDFE (Generalized Decision Feedback Equalizer). A Givens rotation consists of phase extraction, sine/cosine generation and angle rotation parts. Combining two-stage method (coarse and fine stage) and the fixed-width modified-Booth multiplier, we design an efficient QR decomposition processor. By simulations, it is shown that the proposed QR decomposition processor can be a feasible solution for GDFE.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1176-1179
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• 2002

This paper presents the use of a Genetic Algorithm to find the optimal layout for the placement of garment patterns on a fabric of fixed width to minimize fabric waste. We developed a program to simulate garment pieces and their layout on a fixed-width fabric. Each piece in the order book is placed with 2 possible orientations: 0 degrees and 180 degrees. The efficiency is measured by the length of fabric used after all the patterns in the order book have been laid out. A comparison is made between the placement using our proposed genetic algorithm to that made by an expert human using our simulation program. The results from our experiments on various pattern designs indicate that our genetic algorithm can effectively be used to obtain highly efficient solutions, comparable to that done by an expert while using a reasonable amount of time. The algorithm can also be adapted for use in other areas related to optimal consumption of sheet material such as metal, paper, and leather.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.432-438
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• 2011

This paper describes an analysis of optimal design conditions of multi-mode LDPC(low density parity check) decoder which supports three block lengths (648, 1296, 1944) and four code rates (1/2, 2/3, 3/4, 5/6) for IEEE 802.11n WLAN system. A fixed-point model of LDPC decoder, which adopts min-sum algorithm and layered decoding scheme, is implemented using Matlab. From fixed-point simulation results for various bit-width parameters such as internal bit-width, integer/fractional part bit-widths, optimal design conditions and decoding performance of LDPC decoder are analyzed.