• Asian-Australasian Journal of Animal Sciences
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• 제25권7호
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• pp.980-987
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• 2012

In order to investigate the effect of physical forms of starter diets on performance, weaning age, nutrient digestibility and rumen biochemical factors, 24 female of neonatal Brown Swiss calves (average body weight of $39.5{\pm}1.2kg$) were randomly assigned to three treatments. Dietary treatments were mashed (MS), pelleted (PS), and texturized (TS) starter using 8 calves from birth till 90 days of age in each treatment. Diets were formulated to be iso-nitrogenous with 21% crude protein. Based on the experimental results, calves that received PS and TS diets, had significant higher average daily gain (ADG) than those receiving MS (p<0.01). Dry matter intake in calves fed PS and TS was greater than calves fed MS (p<0.05), but there was no significant difference in feed efficiency. Treatments had no effect on initiation of rumination. Weaning age of calves in MS was longer than the other two treatments (p<0.05). Crude protein and organic matter digestibility in MS treated calves were lower than other treatments (p<0.05). No differences were observed in neutral detergent fiber (NDF) and ash digestibility among treatments (p>0.05). Ruminal pH was higher (p<0.01) in MS than the other groups, but ruminal ammonia (g/dl) concentration was not different among the treatments. Body measurements such as body length, pin width, hip width, pin to hip length, size of metacarpus and metatarsus bones, hip height, wither height, stomach size and heart girth were not significantly different among the treatments. Overall, it is concluded that starter diets in the form of pellet and texture can improve performance in neonatal Brown Swiss calves compared to the mashed form.

• 전자공학회논문지C
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• 제36C권6호
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• pp.18-26
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• 1999

본 논문에서는 무선 LAN 표준안 IEEE 802.11의 직접대역확산(Direct Sequence Spread Spectrum) 물리계층을 지원하는 기저대역 모뎀 ASIC 칩의 아키텍쳐와 설계에 대해 기술한다. 구현된 모뎀 칩은 크게 송신부와 수신부로 구성되어 있으며, CRC 부호화/복호화기, 차동 부호화/복호화기, 주파수 옵셋 보상기(frequency offset compensator) 및 타이밍 복구 회로를 포함한다. 구현된 모뎀 칩은 4, 2 및 1Mbps의 다양한 데이타 전송률을 지원하고, DBPSK와 DQPSK의 변조방식을 사용한다. 구현한 모뎀 아키텍쳐는 $SAMSUNG^{TM}$ $0.6{\mu}m$ 게이트 어레이 라이브러리(gate array library)를 사용하여 논리합성을 수행하였으며, 칩의 전체 게이트 수는 53,355개이다. 칩의 동작 주파수는 44MHz이며, 칩의 패키지는 100-pin QFP이고, 전력소모는 44MHz에서 1.2watt이다. 구현된 모뎀 아키텍쳐는 상용화된 HSP3824 칩 보다 우수한 BER성능을 나타낸다.

• 한국의상디자인학회지
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• 제10권1호
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• pp.99-116
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• 2008

This study reviewed pertinent literature and examined relics of manggon(a headband worn to hold a man's topknot hair in place), donggot(a topknot pin), and chigwan(a topknot cover). Before the modernized short hair style, wearing a gat was an important custom. Therefore, manggon, which was used to hold a man's hair in place under the gat, was considered an essential part of the man's official dress code. Donggot is a pin that held the topknot hair in place. It was a must have for a married man, like the binyeo, a lod-like hairpin, for a married woman. Unlike gwanja, it had nothing to do with official rank, but materials were of a variety of materials, including jade and gold. The structure of the donggot was studied in three parts-head, neck and body. Major forms for the head include the mushroom, bean and ball. Bullet and half-cut bullet forms were also found. Forms for the neck include straight-neck and curved-neck. A neck with a belt around a double chin was also found. Forms for the body include the tetrahedron, octahedron and cylinder. The most popular form for silver and white bronze donggot heads was the mushroom, followed by bean and pile forms. Chigwan is also called chipogwan, chichoal, choalgyesogwan, noingwan and sangtugwan. In poetry it was called chichoal, and it used to be called taegogwan in the past as well. Chigwan was so small that it managed to hold a topknot. According to confucian custom in the Joseon period, by wearing chigwan, men didn't display their bare topknot even when they didn't dress up. When they went out, they wore another official hat over the chigwan.

• 한국전자파학회논문지
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• 제15권12호
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• pp.1178-1183
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• 2004

본 논문에서는 정사각형 패치 안테나에 핀 다이오드(PIN diode)를 사용하여 편파변환 특성을 갖는 새로운 형태의 안테나를 제안하였다. 제안된 안테나는 정사각형 패치면 위에 한 쌍의 스퍼라인(spur-line)과 스퍼라인 위에 핀 다이오드를 삽입한 구조이다. 스퍼라인은 핀 다이오드의 on/off특성에 의해 I형 슬롯라인(slot-line)과 L형 스퍼라인의 형태로 변환되어 편파 변환 특성을 나타내었다. 안테나의 측정 결과 선형편파로 동작할 때에는 -15 dB 이상의 낮은 교차 편파 특성을 나타내었고, 원형편파로 동작할 때에는 0.83 dB의 좋은 축비 특성을 나타내었다. 안테나의 -10 dB대역폭은 on/off상태에 따라 각각 $2.1\%$와 $4.1\%$의 특성을 나타내었다. 또한, 원형편파로 동작하는 안테나의 축비 대역폭은 $3.5\%$의 비교적 넓은 대역폭의 특성을 나타내었다. 따라서 제안된 안테나는 동일한 대역폭 안에서 편파 변환 특성을 나타낼 수 있기 때문에 단일 안테나를 이용하여 주파수를 재사용하는 시스템에서 사용할 수 있다.

• 대한치과의사협회지
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• 제55권10호
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• pp.676-687
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• 2017

Objectives : The aim of this study was to evaluate the effects of a composite of bone substitute and collagen barrier membrane (bone patch) for local ridge augmentation at peri-implant dehiscence defects on the clinical efficacy and positional stability in dogs. Materials and methods : Implant placement and ridge augmentation procedure were performed at surgically created peri-implant dehiscence defects in canine mandible (n=6). Four treatment modalities were randomly applied: i) bone patch group, ii) Guided bone regeneration (GBR) without pin fixation group (bone graft and collagen membrane), iii) GBR with pin fixation group, and iv) negative control group. After 12 weeks, clinical, micro-CT and histological analyses were performed. Results : Histologic analysis showed that bone patch group had similar results to GBR group and GBR with fixation group in terms of new bone formation. Micro-CT analysis revealed similar results to histologic analysis in terms of total volume maintenance. Operating time was shorter in bone patch group compared to GBR group and GBR with fixation groups. Conclusions : GBR using bone patch could simplify the ridge augmentation procedure with reduced operating time and equivalent biological performance compared to the conventional procedure.

• 한국표면공학회지
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• 제38권5호
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• pp.202-206
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• 2005

Nitriding treatments were conducted on tool steel (SKD 61) at a temperature of $500^{\circ}C$ for 5 hr using high vacuum direct current (DC) plasma, with ammonia and argon as source gases. The structural and compositional changes produced in the nitrided layers by applying different ratios of Ar to $NH_{3}\;(n_{Ar}/n_{NH3}) were investigated using glancing x-ray diffraction (GXRD), optical microscopy, atomic force microscopy (AFM), micro-Vickers hardness testing, and pin-on-disc type tribometer. Nitriding case depths of around of $50{\mu}m$ were produced, varying slightly with different ratios of $n_{Ar}/n_{NH3}. It was found that the specimen surface hardness was 1150 Hv with $n_{Ar}/n_{NH3}=1, increasing to a maximum value of 1500 Hv with $n_{Ar}/n_{NH3}=5. With a further increase in ratio to $n_{Ar}/n_{NH3}=10, the surface hardness of the specimen reduced slightly to a value of 1370 Hv. These phenomena were caused by changes of the crystallographic structure of the nitride layers, i.e the $\gamma'-Fe_{4}N$ phase only was observed in the sample treated with $n_{Ar}/n_{NH3}$=1, and the intensity of the $\gamma'-Fe_{4}N$ phase were reduced but new phase of $\varepsilon'-Fe_{3}N$, which was known as a high hardness, with increasing $n_{Ar}/n_{NH3}. Also, the relative weight loss of counterface of the pin-on-disc with unnitrided steel was 0.2. And that of nitrided steel at a gas mixture ($n_{Ar}/n_{NH3}) of 1, 5, 7, and 10 was 0.4, 0.7, 0.6, and 0.5 mg, respectively. This means that the wear resistance of the nitrided samples could be increased by a factor of 2 at least than that of unnitrided steel.

• 한국광학회지
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• 제11권5호
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• pp.306-311
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• 2000

본 논문에서는 초음파영역에서 진동하는 물체의 진동주파수와 크기를 측정할 수 있는 레이저 도플러 진동계(Laser Doppler Vibrometer, 이하 LDV)를 설계, 제작하였다. LDV의 광원으로는 파장이 632.8 nm인 He-Ne 레이저를 사용하였으며 Bragg셀에 의해 주파수가 천이되도록 한 마이켈슨형 간섭게 (Michelson interferometer)로 구성하였다. PIN다이오드의 출력은 중심주파수가 40 MHz인 주파수 변조된 신호이며, 이 신호를 증폭하고 주파수를 2.5MHz로 낮춘 후 디지털로 변환하였다. Digital Phase Locked Loop(이하 DPLL)를 사용하여 진동하는 표면의 속도에 비례하는 전압출력을 얻었으며, 이 신호로부터 진동주파수와 크기를 추출하고 주파수특성을 보상하기 위하여 마이크로프로세서를 사용하였다. 그 결과 300 kHz까지의 진동을 측정할 수 있었으며 300 kHz로 진동하는 경우 측정 가능한 최소진폭은 1 nm이었다. 본 연구에서 개발된 LDV는 대용량 전기기기의 부분방전에 의해 발생되는 초음파진동으로부터 최소형 전기 기기의 미세진동까지 측정하는 비접촉식 진동 측정에 사용할 수 있다고 사료된다.

• Journal of Biosystems Engineering
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• 제32권3호
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• pp.190-196
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• 2007

The purpose of this study is to develop a measurement system of cutter conditions for combine header diagnosis during rice harvesting. A load cell was installed at the locker-arm to measure load fluctuation and an acceleration senor was used to monitor vibration signal of cutter bar. The data were collected from a paddy field during harvesting. The tests were conducted with a normal cutter, a loosened cutter, a broken cutter, and a worn-out connecter pin at the field. The vibration signals converted by FFT (Fast Fourier Transformation), filtered, and normalized. The load data and peak values of vibration signals in four different frequency ranges were used to determine the cutting operation and the cutter conditions of combine. The multiple comparison tests showed that the load data and peak values of vibration signals were important to monitor the cutting operation and cutter conditions of combine header.

• 한국생산제조학회지
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• 제6권2호
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• pp.92-101
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• 1997

The purpose of this welding process of the exclusive welding-machine using welding torch-rotation type is to develop a mechanism which can solve the problem of twisting of welding wires and cables. The technique was developed by revising the torch position and smooth controlling of both the normal and reverse rotation. Some of the advantages of using the torch-rotation type apply to the work-rotation technique are the practical uses of increased work space and link work with the factory automation system. Do apply the welding process, I designed and made a special unit so called torch part in order to solve the problems of kinematical. And I made a control panel which can manipulate the progress of the entire process at the work shop. Even if it will be applied to another kind of axle casing's welding work, this process can be utilized if other sizes of the fixed pin and work part is produced and changed. The development of this exclusive welding-machine could reduce the manpower of skilled welding labor and increase productivity and better quality product in comparison to the handmade product.

• 전자공학회논문지C
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• 제35C권2호
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• pp.29-35
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• 1998

This paper describes architectures and design of a SIMD type parallel image processing chip called SliM-II. The chiphas a linear array of 64 processing elements (PEs), operates at 30 MHz in the worst case simulation and gives at least 1.92 GIPS. In contrast to existing array processors, such as IMAP, MGAP-2, VIP, etc., each PE has a multiplier that is quite effective for convolution, template matching, etc. The instruction set can execute an ALU operation, data I/O, and inter-PE communication simulataneously in a single instruction cycle. In addition, during the ALU/multiplier operation, SliM-II provides parallel move between the register file and on-chip memory as in DSP chips, SliM-II can greatly reduce the inter-PE communication overhead, due to the idea a sliding, which is a technique of overlapping inter-PE communication with computation. Moreover, the bandwidth of data I/O and inter-PE communication increases due to bit-parallel data paths. We used the COMPASS$^{TM}$ 3.3 V 0.6.$\mu$m standrd cell library (v8r4.10). The total number of transistors is about 1.5 muillions, the core size is 13.2 * 13.0 mm$^{2}$ and the package type is 208 pin PQ2 (Power Quad 2). The performance evaluation shows that, compared to a existing array processors, a proposed architeture gives a significant improvement for algorithms requiring multiplications.s.