• International Journal of Contents
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• 제8권4호
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• pp.36-41
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• 2012

We present a novel watercolor painting drawing system which can work even on low powered computing machine such as tablet PC. Most digital watercolor systems are generated to perform on desktop, not low powered mobile computing system such as iPad. Our system can be utilized for art education besides professional painters. Our system is not a naïve imitation of real watercolor painting, but handles with properties of watercolor such as diffusion, boundary salience, and mixing of water and pigment.

• 에너지공학
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• 제23권3호
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• pp.163-173
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• 2014

본 연구에서는 도로용 발전장치 최적화 설계를 위해 실험과 수치해석을 다루었으며, 도로용 발전장치는 패드, 축, 토셔널 댐퍼, 일방향 클러치, 기어, 발전기 등의 여러 가지 기계요소를 포함한다. 본 수치해석은 도로용 발전장치의 성능을 평가하기 위하여 개발되었으며 소프트웨어에 의하여 이론적으로 계산된 결과값을 사용하여 최적화 설계의 변수인자를 결정하게 된다. 이러한 변수는 장치의 용량, 길이, 각도 등이며, 차량의 운전상태에 따라서 토오크, 출력 및 생성된 에너지값 등의 결과값을 비교하여, 도로용 발전장치를 설계하기 전 수치해석을 통해 제안된 개념과 시스템이 효율성과 신뢰성을 갖도록 한다.

• ETRI Journal
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• 제33권3호
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• pp.335-343
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• 2011

The pad pitch of modern radio frequency integrated circuits is in the order of few tens of micrometers. Connecting a large number of high-speed I/Os to the outside world with good signal fidelity at low cost is an extremely challenging task. To cope with this requirement, we need reflection-free transmission lines from an on-chip pad to on-board SMA connectors. Such a transmission line is very hard to design due to the difference in on-chip and on-board feature size and the requirement for extremely large bandwidth. In this paper, we propose the use of narrow tracks close to chip and wide tracks away from the chip. This narrow-to-wide transition in width results in impedance discontinuity. A step change in substrate thickness is utilized to cancel the effect of the width discontinuity, thus achieving a reflection-free microstrip. To verify the concept, several microstrips were designed on multilayer FR4 PCB without any additional manufacturing steps. The TDR measurements reveal that the impedance variation is less than 3 ${\Omega}$ for a 50 ${\Omega}$ microstrip and S11 better than -9 dB for the frequency range 1 GHz to 6 GHz when the width changes from 165 ${\mu}m$ to 940 ${\mu}m$, and substrate thickness changes from 100 ${\mu}m$ to 500 ${\mu}m$.

• 대한기계학회논문집A
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• 제26권4호
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• pp.711-719
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• 2002

This paper presents the synchronous vibration control of a rotor system using an active air bearing(AAB). In order to suppress the synchronous vibration, it is necessary to actively control the air film pressure or the air film thickness. In this study, active pads are used to control the air film thickness. Active pads are supported by pivots containing piezoelectric actuators and their radial position can be actively controlled by applying voltage to the actuators. Thus, disturbances, i. e. various kinds of external force can cause shaft vibration as well as change of the air film thickness. The dynamic behavior of a rotary system supported by two tilting-pad gas bearings and its active stabilization using the tilting-pads as actuators are investigated numerically. The $\mu$ synthesis are applied to the AAB system with three pads, two of which contain piezoelectric actuators. To test the validity of the theoretical method, the performance of this control method is evaluated through experiments. The experimental results also show the effectiveness of the control system for suppressing the unbalanced response of the rigid modes.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.491-497
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• 2005

Brake system is indispensible functional part to the transportation machines such as railroad cars, and all of industrial machines. It is mechanical element to stop the movement or slow the speed, transforming kinetic energy of motion object into thermal energy through solid friction. According that recently the railroad cars have become high-speed, the technique in braking domain to secure the overall braking effort is making rapid progress. In particular, material development and manufacturing process are so important to secure friction performance, which is the core in braking performance of mechanical brake units. Wear of brake disk could mainly result in the diminishment of its life span due to thermal cracking, so the endurance against high temperature is required. On the other hand, in this case, the problem is that the side wear of pad, relative material is slightly increased because of enlargement of plastic deformation. It is necessary, therefore, to develop a disk material that will be used in the Tilting System mechanical brake units. The purpose of this paper is to make a study prior to developing brake disk of Tilting Train travelling at 200km/h and to propose the component of brake disk. Accordingly, I will conduct sufficient researches on technical documents of brake disk, that are basic documentations, analyze an impact on components, and further, considering braking degree of train, study for the basic proposal on brake disk's component of the train travelling at 200km/h, which has relatively minor influence of heat stress and maintains the friction. In this respect, I would like to investigate friction characteristics between disk and relative friction material via Test on some possible test segments, analyze and propose friction performance, temperature impact and so forth coming from the contact with pad, relative material to demonstrate the friction characteristics.

• 디지털콘텐츠학회 논문지
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• 제16권5호
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• pp.757-766
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• 2015

최근 첨단기술의 발달과 모바일 인터넷의 사용 증대로 디지털 교과서 개발이 활발해지고 있다. 따라서 본 사례 연구는 2명의 영어 학습자와 교사가 어떻게 디지털 교과서를 통해 학습하고 교수하는지를 관찰과 인터뷰 기법을 통해 탐구했다. 연구 결과 영어 학습자와 교사는 간편하고 다양한 기능과 빠른 인터넷 기반의 디지털 교과서를 통해 교수-학습에 도움을 받은 것으로 나타났다. 그러나 디지털 교과서가 제공하는 많은 양의 정보가 오히려 학습자의 학습을 방해하고, 디지털 교과서를 사용하는데 있어서 교사와 학생 모두 기술적인 어려움을 겼었다고 지적했다. 더 효과적인 디지털 교과서 활용을 위해 영어 교사는 언어적 지식과 더불어 기술적 지식을 학습자에게 전달하고 학습자 주도 학습을 위한 가이드 역할을 수행해야 할 것이다.

• 한국식품영양과학회지
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• 제32권6호
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• pp.882-886
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• 2003

고추장은 체중감소 효과를 보였는데 흰쥐를 이용한 식이섭취 실험에서 발효 숙성된 전통고추장이나 공장식 상품고추장은 고지방 식이로 인한 체중 증가를 감소시켜 정상에 가까운 체중을 유지하도록 하였다. 반면에 발효되지 않은 고추장의 경우 고춧가루군과 거의 비슷한 감소효과를 나타내었으며 발효된 전통고추장이나 공장식 상품고추장에 비해서 체중감소효과가 그리 크지 않았다. 발효된 전통고추장은 높은 체중 감소효과와 더불어 부고환 지방 및 신장 주위 지방조직의 총지방, TG, 콜레스테롤의 함량도 낮추는 효과를 나타내었으나 발효되지 않은 고추장식이군은 감소효과가 크지 않아 발효의 유무가 체중감소, 지방조직감소에 큰 변수임을 알 수 있었다.

• 한국가정과학회지
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• 제8권1호
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• pp.19-24
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• 2005

This paper is to know the possibility of coloration of synthetic fibers with loess. Fabrics woven with polyester, nylon, and acrylic fibers were dyed by a dip-pad operation with a laboratory mangle. Drying, curing at 180$^{\circ}C$ for 10 minutes and washing were followed. Effect of curing after drying were investigated in terms of K/S values and SEM microphotographes. Reddish-yellow(a:75.13, B:15.14, ${\Delta}$E:45.31) colored fabric ascertain possibility of coloration of synthetic fibers with loess. Acrylic fiber shows highest dye uptake of the three kinds of fibers and fastness increases by curing after drying.

• 한국전기전자재료학회논문지
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• 제27권11호
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• pp.686-689
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• 2014

Electrostatic discharge has been considered as a major reliability problem in the semiconductor industry. ESD reliability is an important issue for these products. Therefore, each I/O (Input/Output) PAD must be designed with a protection circuitry that creates a low impedance discharge path for ESD current. This paper presents a novel Lateral Insulated Gate Bipolar (LIGBT)-based ESD protection circuit with latch-up immunity and high robustness. The proposed circuit is fabricated by using 0.18 um BCD (bipolar-CMOS-DMOS) process. Also, TLP (transmission line pulse) I-V characteristic of proposed circuit is measured. In the result, the proposed ESD protection circuit has latch-up immunity and high robustness. These characteristics permit the proposed circuit to apply to power clamp circuit. Consequently, the proposed LIGBT-based ESD protection circuit with a latch-up immune characteristic can be applied to analog integrated circuits.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.133-134
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• 2008

Usability study of the CU Medical "i-PAD" AED was conducted to validate the usability of the device, primarily focused on the trained user as well as the utility of the training material. Comparing these results of the trained participants to those obtained by Callejas et al. (2004), who studied video-trained users of two commercially available Philips AEDs (FR2 and HS1) using a male manikin only, the participants in this study were more successful (100% vs. 85.7%-FR2 vs. 88.9%-HS1) and faster to shock (58.5s-i-PADvs. 91s-FR2 vs. 90s- HS1). While the focus of this study was on validating ease of use for trained bystanders, the results of the untrained condition showed that, from a usability perspective, these devices perform as well as any other AEDs already approved and available for purchase for untrained bystander use, as evidenced by the comparison to various published research results