• 자원리싸이클링
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• 제7권1호
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• pp.14-19
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• 1998

비산회에 함유된 잔류 혹은 미연소된 탄소분을 회수하고, 이 미연탄소분의 물리·화학적 특성을 조사하였다. 이연탄소분이 농축된 시료는 비산회를 정제하기 위해 사용되는 부선법을 사용하여 얻었다. 얻은 미연탄소분 시료가 함유하는 탄소분의 총량과 공업 분석을 하였다. 회수된 탄소분에 잔류된 회의 양과 화학조성도 분석하였다. 이외에 탄소분의 크기 분포, 표면적, 기공의 크기, 결정 구조 및 밀도 등과 같은 물성을 측정하였다.

• 소성∙가공
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• 제14권7호
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• pp.613-618
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• 2005

The paper is concerned with the process design and the die design for manufacturing the preform of a large pressure vessel. The cold-working processes are introduced to improve the fatigue strength and to simplify the manufacturing process. By the finite element simulation, the parameter design is carried out, which is subjected to constraints such as the blank sire, press capacity and other minor limitations. The proposed design results are verified by the model experiments, in which the model is scaled down to one tenth of the original size.

• 전자공학회논문지SC
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• 제40권1호
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• pp.45-54
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• 2003

종래의 터보기기는 회전자의 높은 회전속도를 얻기 위하여 증속기어를 사용하였으나 근래에는 초고속 전동기를 적용하여 기계적인 효율 및 시스템의 소형차에 관한 연구가 활발히 진행중이다. 본 논문은 직접구동방식의 터보 압축기를 위한 초고속 영구자석 동기전동기 구동시스템에 관한 논문으로서 150마력 70,000rpm 영구자석 동기전동기 구동시스템을 개발하여 상품에 적용하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제8권4호
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• pp.375-378
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• 1995

Three month old 600 ducklings of Khaki Campbell/KC Desi and KC X Desi were reared for a period of 13 months in the villages surrounding Bangladesh Agricultural University in order to study the economic traits of duck with and without extra feed to scavenging system of rearing. KC attained earlier sexual maturity followed by KC X Desi and Desi ducks and crossbred showed closeness to sire breed for this trait, KC X Desi found heavier and produce more eggs than their parental breeds. KC showed higher hatchability followed by KC X Desi and Desi ducks were more resistant followed by KC X Desi and KC to diseases. Extra feeding were found more beneficial to ducks irrespective of breed and types.

• 한국분무공학회지
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• 제2권4호
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• pp.22-28
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• 1997

In this paper an experimental study of a spray created by two impinging jets is presented utilizing a novel two-reference-beam double-pulse holographic technique. Visualization of the overall spray pattern as well as measurements on the size and velocity of the droplets were performed with the special emphasis on the effect of physical properties of liquids. The overall spray pattern clearly revealed the inherent wave nature In the disintegration process of this type of atomization. The structure of liquid elements near the impingement point is indicative of the mechanisms of the disintegration process. Surface tension plays an important role in the droplet size without any noticeable effect on the spray pattern, whereas viscosity affects the structure without any significant effect on the droplet sire. The droplet velocities were not affected by liquid properties.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.351-355
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• 1999

The amount of data stored, processed and transmitted in the multi-media systems has been growing very fast, especially for the image data. For example, it takes 0.75Mbytes to store 512 12 pixels of 24-bit color image. A video signal with 30 frames per second will require 22.5Mbytes of storage space. To solve this problem, we need a good image compression technique. Recently, many researches on the image compression technique based on the wavelet transform are being pursued to overcome the problems of traditional JPEG. This paper describes the architecture and design of two-dimensional wavelet transform circuit. To keep the sire of the circuit small, we tried to minimize the internal storage space by using external SDRAM. This circuit was designed in Verilog-HDL, synthesized using Design Compiler and verified using Verilog-XL.

• 제어로봇시스템학회논문지
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• 제8권10호
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• pp.881-889
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• 2002

Mobility analysis for various mobile mechanisms including mechanisms with lack of geometric generality is performed. Joint screws are employed to find the sire of feasible joint motion space or each of independent loops of mobile mechanisms. Particularly, the concept of "representative screws" is introduced to represent the feasible motion spaces for subsets of joints belonging to either a loop or a sub-system consisting of several closed loops. Firstly. simplified joint model for each of low different typical wheels popularly employed in mobile robots is described. Then. mobility analysis fir various types of planar mobile robots and the Mars Rover mobile robot for navigation on the rocky road on Mars arc performed. It is confirmed that the obtained results in this study coincide with the previous ones which were obtained by suing imaginary Joints approach(1)pproach(1)

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.642-647
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• 1998

A Poisson error model as a generalized linear mixed model (GLMM) has been suggested for genetic analysis of counted observations. One of the assumptions in this model is the normality for random effects. Since this assumption is not always appropriate, a more flexible model is needed. For count traits, a Poisson hierarchical generalized linear model (HGLM) that does not require the normality for random effects was proposed. In this paper, a Poisson-Gamma HGLM was examined along with corresponding analytical methods. While a difficulty arises with Poisson GLMM in making inferences to the expected values of observations, it can be avoided with the Poisson-Gamma HGLM. A numerical example with simulated embryo yield data is presented.

• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.88-96
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• 2000

The present study estimated the variation of early survival of chum salmon families with respect to temperature and size after transfer to seawater. Heritability for seawater tolerance of half-sib families was also estimated at 45 days after hatching. Gametes were collected from 6 male and 18 female chum salmon to make 18 paternal half-sib families. Seawater tests were carried out at 3, 7 and $12^{\circ}C$ of $32\%$ seawater and compared with freshwater. Survival was significantly affected by seawater temperature. The highest seawater tolerance was obtained in 45-day old chum salmon at $7^{\circ}C$ seawater and the lowest seawater tolerance was obtained at $3^{\circ}C$. Overall survivals in seawater tolerance at $32\%$ varied among families. There were significant variance in fry survival among females (P=0.0001), and among males (P=0.0001). The heritabilities of survival in seawater in chum salmon were estimated to be 0.32-0.34 for the sire components at 45 days after hatching in 1998.

• 한국정밀공학회지
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• 제20권4호
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• pp.183-188
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• 2003

Particulate contamination is known to be a significant cause of failures of removable storage media. In this work, the effect of particles on the surface damage of removable hard disk media was investigated. The particles of different materials and size were introduced to the Head Disk Interface (HDI) using a particle injection system. It was round that the particles of particulate size and property serious damaged the media. This study showed that cleaning pad is effective for reducing particle contamination, except fer the particles of specific size and property. As a means to remove the particles of specific sire. the concept of using a stepped taper at the leading edge of the slider is proposed.