• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.1296-1299
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• 2001

In this paper, a simple, novel approach is proposed for a variable hysterisis band current controller which uses feedback techniques to achieve constant switching frequency with good dynamic response. The simulation result shows constant switching frequency and consequenctly the load current ripple decrease.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.611-613
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• 2001

In this paper, the force test of arch-type LIM is treated. The method of direct measurement is used load-cell on 3-component force guage. Indirect method is used search coil on LIM. PC-based data aquistion system include two method and measure the force in driving state. Measured data of direct and indirect method are analyzed and compared.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.221-223
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• 2005

In a CDMA system, the capacity is variable and mainly depends on multiple access interference. The multiple access interference has a deep relationship with transmitted or received power. The capacity of CDMA2000 1x system is considered to be limited by the forward link capacity. Different rate data traffic requires different transmitted power and rate controlling enables the system utilize radio resource more efficiently. A very simple rate control algorithm fer data calls in CDMA2000 1x system is proposed. In the proposed algorithm, by monitoring the total transmit power, we can simply adjust data rate to channel conditions and efficiently use radio resources. The proposed algorithm is easy to implement in power controlled CDMA systems.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2007.06a
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• pp.51-55
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• 2007

본 논문은 LCD 생산라인의 물류 자동화 시스템 중 컨베이어와 같은 선형 이송시스템에 적용이 가능한 영구자석 여자 횡자속 선형전동기 개발에 관한 내용이다. 3차원 등가 자기 회로망법을 이용한 해석과 3축 Load Cell을 이용한 정특성 실험을 통해 횡자속 선형전동기의 특성을 비교, 분석하여 물류 이송이 가능한 횡자속 선형전동기 추진모듈의 사양을 결정하였고, 시작품을 설계, 제작하여 컨베이어 시스템 등의 이송시스템에 적용 가능성 및 그 타당성을 검토하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.379-380
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• 2009

한국항공우주연구원 추진기관팀은 1999년 10월에 3,000 lbf 급 고공환경 엔진시험 설비를 갖추고 소형 가스터빈 엔진의 고공환경 성능시험에 이를 활용하고 있다. 하지만 새롭게 2008년부터 고공환경 성능시험을 진행하고 있는 엔진은 1,000 lbf 미만의 초소형 엔진으로써 기존 추력측정 시스템을 이용하여서는 정확한 추력의 측정을 보장할 수 없다. 본 논문에서는 초소형 엔진의 고공환경 성능시험 수행을 위한 추력대의 구축 과정을 다루고 있다.

• Journal of Korean Association for Spatial Structures
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• v.6 no.3 s.21
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• pp.35-41
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• 2006

Various monitoring sensors have been used for the monitoring, damage and vibration prediction of structures. They have been used for sensing damage in a variety of materials and structures such as piezoelectric materials (PZT) and electric strain gauges. But, many experiments of vibration were not performed. The PZT changes physical force if load cell to electrical signal due to deformation of structure. The voltage change of piezoelectric sensors for plates are used for vibration prediction. In this study, a fundamental study for vibration prediction using piezoelectric sensors are discussed in plates.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.6
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• pp.734-739
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• 2006

Statement of problem. Many surface processing methods of dental implant have been developed, the laser processing is one of them. Purpose. This study was to investigate in vitro the fatigue resistance of implants treated with laser method(CSM implant, CSM Company, Daegu, Korea). Material and methods. Fatigue tests of 23 laser treated CSM implant(CSM Company, Daegu, Korea) were conducted using Instron 8871 (Load cell, 5 kN, Instron Co., England), according to ISO 14801 (2003), Results. From 300 N, each specimens were not fractured and withstood until more than 5,000,000 cycle. Conclusion. Within the limits of this in vitro study, implants treated with laser method (CSM implant, CSM Company, Daegu, Korea) have had enough rigidity and fatigue resistance to use clinically with reliance.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1243-1246
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• 2006

A new source follower circuit for the integrated circuit of AMLCDs is proposed. Active load is added and calibration operation is applied to compensate the circuits. Proposed circuit is capable of minimizing the variation from both timing and device variations through measured results, the uniformity and bias effect are discussed.

• KIEAE Journal
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• v.4 no.3
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• pp.121-128
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• 2004

One of the most weak parts for energy loss through the whole building components are building envelopes. Lots of technbologies to increase the thermal performance of building envelopes have been introduced in recent years. Transparent insulation is a new technology for building insulation and has function both solar transmittance and thermal insulation. This study has been carried out to develope the transparent insulation panels and TI-wall system and to analyze the thermal performance of TI-wall system by experiments using test-cell and dynamic energy simulation program ESP-r 9.0. This system is regarded as a efficient building envelope system suitable for to reduce the heating and cooling load of the buildings in our country.

• Journal of Mechanical Science and Technology
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• v.16 no.2
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• pp.255-261
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• 2002

A newly designed mass-detecting capillary viscometer uses a novel concept to continuously measure non-Newtonian fluids viscosity over a range of shear rates. A single measurement of liquid-mass variation with time replaces the now rate and pressure drop measurements that are usually required by capillary tube viscometers. Using a load cell and a capillary, we measured change in the mass flow rate through a capillary tube with respect to the time, m(t), from which viscosity and shear rate were mathematically calculated. For aqueous polymer solutions, excellent agreement was found between the results from the mass-detecting capillary viscometer and those from a commercially available rotating viscometer. This new method overcomes the drawbacks of conventional capillary viscometers meassuring non-Newtonian fluid viscosity. First, the mass-detecting capillary viscometer can accurately and consistently measure non -Newtonian viscosity over a wide range of shear rate extending as low as 1 s$\^$-1/. Second, this design provides simplicity (i. e., ease of operation, no moving parts), and low cost.