• 유공압시스템학회논문집
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• 제7권1호
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• pp.6-10
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• 2010

A measurement of very high torque for track drive unit in construction equipment is usually in difficulties due to the requirement of a torque meter with high capacity, and the limitation of geometry for an experimental set-up. To improve the troublesome problem, a new device was proposed, where a torque transmitted through the torque arm can be measured by load cells attached at each torque arm. The experimental set-up of the new device was carried out in order to measure the torque values for a mechanical feedback type planetary gear box, in which the power flow circulates itself in a closed-loop. The new device enables to measure torque values of 60,000Nm. Additionally, the measured values were estimated statistically in the aspect of their repeatability and reproducibility, so that an acceptable behaviour as a measuring device can be confirmed.

• 반도체디스플레이기술학회지
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• 제7권2호
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• pp.55-58
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• 2008

The objective of the research is to design, manufacture and test a Mass Flow Controller(MFC) capable of measuring compressible fluid flows based on a "bucket and stop-watch"method. The basic principle is the measurement of time, where the time taken to fill and empty a bucket of known volume is measured. This method of flow measurement is a new concept when compared to a commercilized current mass flow controller. For the flow meter to be able to compete with established designs it not only must be comparable in cost and robustness, it must be very accurate and reliable as well. This device should be able to handle fluid flows in the range of 0.1ml/min to 10ml/min within an accuracy of ${\pm}$1%. A possible application for a device such as this is in electronics industry where arsenic gas is used in the production of silicon chips.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.857-858
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• 2012

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.825-828
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• 2000

The objective of the present study is to develop a new device that the viscous characteristics of fluids are determined by applying the unsteady flow concept to the traditional capillary tube viscometer. The capillary tube viscometer consists of a small cylindrical reservoir, capillary tube, a load celt system oat measures the mass flow rate, interfacers, and computer. Due to the small size of the reservoir the height of liquid in the reservoir decreases as soon as the liquid in the reservoir drains out through the capillary and the mass flow rate in the capillary decreases as the hydrostatic pressure in the reservoir decreases resulting in a decrease of the shear rate in the capillary tube. The instantaneous shear rate and. driving force in the capillary tube are determined by measuring the mass flow rate through the capillary, and the fluid viscosity is determined from the measured flow rate and the driving force.

• 반도체디스플레이기술학회지
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• 제7권3호
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• pp.55-58
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• 2008

The objective of this research is to design, manufacture and test a mass flow controller capable of measuring compressible as well as incompressible fluid flows based on a 'bucket and stop-watch' method. The basic principle behind such a system is the measurement of time, where the time taken to fill and empty a bucket of known volume is measured. This device should be able to handle fluid flows in the range of 0.1 ml/min to 10 ml/min within an accuracy of ${\pm}$1%. For the flow meter to be able to compete with established designs, it must be not only comparable in cost and robustness, but also very accurate and reliable as well.

• 대한치과재료학회지
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• 제43권1호
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• pp.17-28
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• 2016

The aim of this study was to evaluate the changes in dentinal permeability after application of dentin desensitizer on exposed dentin immediately after ultrasonic scaling to teeth with non-carious cervical lesions. Thirty caries-free extracted molars were fixed to slide glasses after horizontally being sectioned at 5 mm below the cemento- enamel junction (CEJ). The prepared specimen was connected to a fluid flow measuring device (nano-Flow), and a V-shaped cavity was formed at the CEJ to imitate the non-carious cervical lesion. After no fluid leakage was confirmed in the connected system with specimen, tooth surface was treated ultrasonic cleaning with piezoelectric ultrasonic scalers until dentinal tubules were exposed. And 6 different desensitizers were applied on exposed dentin. Real-time measurements of dentinal fluid flow were performed during ultrasonic scaling and application of dentin desensitizer. To evaluate the occlusion of exposed dentinal tubules, tooth surface was examined by SEM. Following results were observed. After ultrasonic scaling, more dentinal tubules were exposed on the tooth with non-carious cervical lesions compared to tooth without lesions. The rate of fluid flow measured with nano-Flow system had correlation with the degree of dentin occlusion observed with SEM after application of desensitizers on exposed dentin. Desensitizers with glutaraldehyde and HEMA did not decrease the rate of fluid flow and did not show dentin occlusion. Desensitizers with oxalate showed the limited effects on the rate of fluid flow and dentinal tubule occlusion. Desensitizer with resin monomer showed the significant effect on the rate of fluid flow and dentin occlusion.

• Korea-Australia Rheology Journal
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• 제19권2호
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• pp.75-80
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• 2007

The slotted plate technique has previously been shown to be a successful method for directly measuring the static yield stress of suspensions. In this study, we further establish the usefulness of the slotted plate device as a rheometer especially at low shear rates, taking advantage of the extremely low speeds of the slotted plate technique. Newtonian fluids, a shear thinning fluid, and yield stress fluids were tested using the slotted plate device and the results were compared with those from a commercial rheometer using different standard flow geometries. The relationship between the stress on the plate and the viscosity for the slotted plate device obtained by dimensional analysis (drag) predicts a linear relationship between the force at the plate and the plate speed, consistent with the experimental data. The slotted plate device can measure viscosities at very low shear rates. The apparent viscosity - shear-rate data obtained from the slotted plate device are complementary to those obtained using a commercial rheometer. That is : the slotted plate can measure viscosity in the shear rate range $10^{-7}<\dot{\gamma}<10^{-3}\;s^{-1}$, while the commercial rheometer measures viscosity at shear rates higher than $10^{-3}\;s^{-1}$.

• 제어로봇시스템학회논문지
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• 제12궈1호
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• pp.85-92
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• 2006

A new silicon micro flow sensor with multiple temperature sensing elements was proposed and fabricated in considering wide range flow velocity measuring device. Thermal mass flow sensor measures the asymmetry of temperature profile around the heater which is modulated by the fluid flow. A micro mass flow sensor was normally composed of a central heater and a pair of temperature sensing elements around it. A new 2-D wide range micro flow sensor structure with three pairs of temperature sensing elements and a central heater was proposed and numerically simulated by Finite Difference Formulation to confirm the feasibility of the wide flow range sensor structure. To confirm the simulation result, the new flow sensor was fabricated on silicon substrate and the basic flow sensing properties of the sensor were measured.

• Restorative Dentistry and Endodontics
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• 제35권5호
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• pp.313-320
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• 2010

연구목적: 본 연구의 목적은 미세 유체 흐름 측정장치를 이용해서 각 상아질 지각과민 처치제의 적용 과정 중 발생하는 상아 세관액 흐름의 유동을 관찰하고, 상아질 지각과민 처치제 간 적용 후 투과도 감소의 차이를 비교하고자 하는 것이다. 연구 재료 및 방법: CEJ 5 mm 하방에서 절단한 소구치를 미세 흐름 측정장치에 연결하여 20 cm $H_2O$의 정수압을 가하였다. 치경부에 상하 3 mm, 근원심 4 mm, 깊이 2 mm의 V자 형태의 5급 와동을 형성하고 smear layer를 제거하기 위해 15초 동안 산 부식한 후 상아질 지각과민 처치제를 적용하였다. 사용된 상아질 지각과민 처치제는 Seal&Protect (SP), SuperSeal (SS), BisBlock (BB), Gluma desensitizer (GL), Bifluoride 12 (BF) 이다. 상아세관액의 흐름은 지각과민 처치제 도포 전부터 도포 후 5분까지 실시간으로 측정되었다. 결과: 실험에 사용한 모든 상아질 지각과민 처치제는 적용 후의 상아세관액 흐름율이 적용 전에 비해 유의하게 감소하였다(p < 0.05). SP는 GL과 BF에 비해 유의하게 투과도 감소가 나타났다 (p < 0.05). SS와 BB는 BF에 비해 유의하게 투과도 감소를 보였다 (p < 0.05). 결론: 지각과민 처치제의 도포 과정 동안 각 처치제의 특징적인 상아세관액의 유동을 미세 유체 흐름 측정장치를 통해 관찰 할 수 있었다.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.99-102
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• 2005

This study was conducted for obtaining the optimized data to build the mixer or micro fluid device as measuring the three dimensions flow field in micro mixer. To acquire the rapid diffusion on the region of low Reynolds (Re < 100), the staggered herringbone mixer using chaotic advection was selected in this case. At first, by conducting the numerical analytical virtual experiment using CFD-ACE+, three dimensions flow field in the micro mixer was estimated As this flow field was proven using defocusing particle tracing method, the behavior of micro flow with three dimensional aspects could be analyzed. Numerical analysis and flow pattern in the micro mixer by experimental verification made to be able to analyze the chaotic advection. These can be important sources for building more optimized form. Verifying the information of three dimensional flow structure, these information can be used as the data for developing and improving the $\mu$ -TAS.