• 한국세라믹학회지
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• 제53권5호
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• pp.478-482
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• 2016

Metal-supported SOFCs have been investigated to overcome the disadvantages of ceramic-supported SOFCs, including issues related to mechanical strength and sealing. In the case of ceramic-supported cells, the mechanical support is a brittle ceramic or cermet, and it contains expensive materials. However, metal-supported cells utilize ceramic layers that are only as thick as necessary for electrochemical functioning, thereby compensating for the disadvantages of ceramic-supported cells. The mechanical support is fabricated from inexpensive and robust metals, and the electrochemically active layers are applied directly to the metal support. The metal-supported SOFCs thus can provide a reduced system cost, ease of manufacturing, and operational advantages. Owing to these features, metal-supported SOFCs are a very promising candidate for commercialization. Given the importance of studying worldwide trends in metal-supported SOFC research for performance evaluation, this paper reviews development trends with a focus on fabrication methods. Furthermore, a novel fabrication method developed in KAIST is discussed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.360-363
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• 2001

The conventional 60(Hz) power supply for driving magnetron in microwave oven has disadvantages of heavy weight and low efficiency due to 60(Hz) High Voltage Transformer(HVT), capacitor and the phase control of thyristors with open-loop controller. To alleviate these disadvantages, this paper proposes a 20(kHz) phase-shifted(PS) Full-Bridge(FB) Zero- voltage-Switched(ZVS) PWM converter to drive a 600(W) magnetron in an 1(kW) microwave oven and to control the average anode current.

• 한국정밀공학회지
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• 제20권3호
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• pp.97-104
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• 2003

This paper proposes a new parallel manipulator fur plane motion, and then discusses on the workspace and kinematical characteristics of the manipulator. The conventional planar parallel manipulators have some disadvantages which are complex non-closed type direct kinematics, workspaces containing useless voids, and concave type border tines of workspaces. The proposed planar parallel manipulator overcomes the above disadvantages, that is, the manipulator has simple closed type direct kinematics, a void-free workspace, and a convex type borderline of a workspace. This paper shows the simulation result of the workspace as well as performances indices using a homogeneous inverse Jacobian.

• Journal of the korean society of oceanography
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• 제31권2호
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• pp.97-106
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• 1996

Advantages and disadvantages of four radioisotopic methods, $^{3}H$-thymidine, $^{3}H$-adenine, $^{3}H$-leucine, and $^{35}S$-sulfate, for measuring bacterial production were reviewed. The maior issues discussed in production methods were: (1) whether all the actively growing bacteria take up the radiolabeled (organic) tracers; (2) how each target molecule should be purified (nonspecific labeling); and (3) how important the determination of the precursor pool specific activity is (internal isotope dilution). Since all the radioisotoic methods have their own advantages and disadvantages, careful consideration must be paid in choosing the radioisotope according to the conditions of each environment investigated.

• 대한의용생체공학회:의공학회지
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• 제39권6호
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• pp.268-277
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• 2018

With drastic change in the market and technology of medical devices, a comparative analysis is necessary in advanced systems internationally in order to prepare domestically applicable plans for improvement in classification and differential grade management for items of medical devices. This research examines and analyzes the differences of definition and legal systems of medical devices among Korea, United States, EU, Japan and China, and investigates classification and grading system of each country to identify disadvantages of classification and grading structures for medical device in Korea. This research suggests ways to supplement the disadvantages of domestic classification and grading system of medical devices, and elicits differential management plans for medical devices.

• 로봇학회논문지
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• 제16권1호
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• pp.29-34
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• 2021

Traditional actuation system such as electric and pneumatic actuator has obvious advantages and disadvantages. To combine advantages and compensate disadvantages of the traditional actuation, a pneumatic actuation system with an internal air pressure source is noteworthy approach. In this paper, a soft pneumatic actuation system based on origami pump is described for haptic feedback glove. To improve wearability, an origami pump is introduced because the origami pump is much lighter than air compressor. The miniaturized electric actuation system is also designed with 3D printed planetary gear in order to reduce the volume of the system. To figure out the performance of the system, shrinkage distance of origami pump was measured with vision camera. The pressure in the origami pump was also estimated to understand the performance of the system.

• Journal of Astronomy and Space Sciences
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• 제39권3호
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• pp.99-108
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• 2022

There are two models that explain the rotation curves of galaxies: dark matter, which gives the missing contribution to the gravitational potential of the standard theory of gravity, and modified theories of gravity, according to which the gravitational potential is created by ordinary visible mass. Both models have some disadvantages. The article offers a new look at the problem of galactic rotation curves. The author suggests that the moment of inertia creates an additional gravitational potential along with the mass. The numerical simulation carried out on the example of fourteen galaxies confirms the validity of such an assumption. This approach makes it possible to explain the constancy of gas velocities outside the galactic disk without involving the hypothesis of the existence of dark matter. At the same time, the proposed approach lacks the disadvantages of modified theories of gravity, where the gravitational potential is created only by the mass of visible matter.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.61-62
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• 2022

The unit quantity is an important factor influencing the durability, workability, and quality of concrete. Methods for measuring the unit quantity include a high frequency heating method, a unit volume mass method, a capacitance method, and a microwave method. However, these methods have disadvantages of poor measurement method, time required, and accuracy, and a relatively experimental method compensating for these disadvantages was used to measure the unit quantity using a high frequency main sensor (FDR) capable of simple and fast measurement. In addition, the unit quantity was evaluated by analyzing the measurement data through deep learning.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.187-187
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• 2020

Recently, interest in sprout crops using various varieties such as barley and oats has increased. However, in case of wheat, there were disadvantages in that the growth rate was slow and the economic efficiency and utilization were reduced. In order to overcome these disadvantages, this study was conducted on the selection of wheat varieties suitable for cultivation of wheat sprouts. Also, we analyzed the various functional ingredients of wheat sprouts.

• Journal of Welding and Joining
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• 제24권2호
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• pp.5-9
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• 2006