• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.15 no.6
• /
• pp.251-255
• /
• 2015

In this paper, we propose a fuse controller which is used for storing the optimal value or the correction value for the surrounding product of the IoT applications and it is implemented serial communication circuit using a single pin. Because of the proposed single pin protocol is simpler in the hardware than the conventional $I^2C$ and SPI using two or more pins, it is suitable for the area of small amount of data transmission. The function of the one pin protocol is verified by logic simulation and the FPGA test board and it is fabricated using CMOS 0.35um technology. It is expected to use the IoT product that require the low power consumption and simple hardware.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.35 no.2
• /
• pp.105-112
• /
• 2011

The objective of this study is to predict the heat-transfer performance of a spirally coiled circular fin-tube evaporator in which either R134a or R600a was used; this heat-transfer performance was predicted by varying the mass flow rate, inlet air temperature, air flow rate, and tube thickness. Mean deviation for the analytical model from the measured data was ${\pm}8.3%$. Simulation results revealed that at a given mass flow rate, the heat-transfer rate of the evaporator using R600a was higher than that usingR134a because the enthalpy of the former is higher than that of the latter at the given conditions. The heat-transfer rate of both refrigerants increased with an increase in the air flow rate and inlet air temperature but decreased with an increase in the tube thickness.

• Composites Research
• /
• v.32 no.6
• /
• pp.314-318
• /
• 2019

A simple and very flexible automatic dipping machine was constructed for producing functional multilayer films on wide substrates via the layer-by-layer (LbL) assembly technique. The proposed machine exhibits several features that allow a fully automated coating operation, such as various depositing recipes, control of the dipping depth and time, operating speed, and rinsing flow, air-assist drying nozzles, and an operation display. The machine uniformly dips a substrate into aqueous mixtures containing complementary (e.g., oppositely charged, capable of hydrogen bonding, or capable of covalent bonding) species. Between the dipping of each species, the sample is spray cleaned with deionized water and blow-dried with air. The dipping, rinsing, and drying areas and times are adjustable by a computer program. Graphene-based thin films up to ten-bilayers were prepared and characterized. This film exhibits the highly filled multilayer structures and low thermal resistance, indicating that the robotic dipping system is simple to produce functional thin film coatings with a variety of different layers.

• Journal of Korean Society of Steel Construction
• /
• v.18 no.5
• /
• pp.525-534
• /
• 2006

Column-to-beam pinned connections can cause local moment to the web of a steel tube due to the distance of eccentricity between the row of bolts and the column flange, which possibility deteriorates the load capacity of column. In this study, a square hollow section tubular used finite element analysis of a square hollow section tubular column was carried out, and the column width and thickness, existence and non-existence of internal reinforcement, and existence and non-existence of compressive force were taken as variables to examine the load capacity deterioration of a square column caused by moment. To guarantee the reliability of the finite element results, some specimens were fabricated and tested. The yield line method was applied to suggest the strength formulas of the square tubular column to the beam pinned connections. Based on the study results, the column strength the moment of the square hollow section tubular column to the beam pined connections improved with the increase in the w to strength limitations, a no-reinforcement type of square hollow section tubular column was proposed, and if the limitation values were not satisfied, the reinforcement of the internal column was made mandatory. Therefore, the horizontal -reinforcement type considered the strength increase, and the fabrication of the square hollow section tubular column was ar column that considered its load capacity with the moment for the no-reinforcement and the horizontal-reinforcement types.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.879-882
• /
• 1998

본 논문에서는 리드 피치가 15mil인 208핀 QFP칩을 검사하는 고해상도의 비젼 모델 시스템을 개발하였다. 전체적인 하드웨어와 고해상도에 적합한 알고리즘 및 이를 실현하는 프로그램을 개발하였으며, 특히 칩 리드 검출을 위한 새로운 알고리즘을 제안하였다. 본 논문에서는 제안한 방법의 특징은 조명의 간섭에 대해 강하며 검사 속도 및 정밀도가 향상되었다.

• Journal of Advanced Marine Engineering and Technology
• /
• v.34 no.5
• /
• pp.711-717
• /
• 2010

In this paper, a new automatic punching system that generates pinholes expressing texts or images on a plastic plate is developed. The pin-holed plate is used as a new glamorous display board reflecting colourful lights from the light emitting diode (LED) installed on the edge side of the plate. The punching system has four actuators which work together to make multiple holes with accurate position and depth on the plastic plate. For even reflection of the lights from texts or images on the board and fast production of the pin-holed boards, we developed an accurate actuating structure of the system cooperating with a PID control algorithm. We also built a GUI-based integrated control system to help users easily design luminous texts or images on the plastic plate. Also, we conducted a performance test of the system to verify the punching speed and depth control of the pin holes on the plastic plate.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.32 no.3
• /
• pp.102-110
• /
• 2004

A design code validated against the thermal analysis results of CFD and published RTE code for a regeneratively cooled combustion chamber has been developed. The major function of the code is to predict the regenerative cooling performance and stress of the chamber wall. Adopted are the empirical correlation for the evaluation of the heat transfer coefficient of hot gas and coolant, and theoretical formula for the fin effect of the channel rib. The hot-gas-side wall temperature from the present code shows 100 K difference at most compared to RTE results. It shows less than 10 % difference for the heat flux thrall through the chamber wall and hot-gas-side convective heat transfer coefficient. The major cause of the wall temperature difference is due to the underestimation of the fin effect of the channel rib.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.24 no.5
• /
• pp.207-212
• /
• 2014

An ultrathin sheet-like carbon nanostructure provides an important model of a two-dimensional graphite structure with strong anisotropy in physical properties. As an easy and cheap route for mass production, RF thermal plasma synthesis of freestanding carbon nanosheet from $CH_4$ (Methane) and $C_3H_8$ (Propane) is presented. Using vapor synthesis process with RF inductively thermal plasma, carbon nanosheets were obtained without catalysts and substrates. The synthesized carbon nanosheets were characterized using transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis. The carbon nanosheets synthesized using methane and propane generally showed 5~6 and 15~16 layers with a wrinkled morphology and size of approximately 100 nm.

• Journal of Digital Convergence
• /
• v.13 no.7
• /
• pp.197-205
• /
• 2015

Existing Web authentication method utilizes the resident registration number by credit rating agencies separating i-PIN authentication method which has been improved authentication using resident registration number via the real name confirmation database. By improving the existing authentication method, and it provides the available integrated ID authentication on Web. In order to enhance safety, the proposed authentication method by encrypting the user of the verification value, and stores the unique identifier in the database of the certificate authority. Then, the password required to log in to the Web is for receiving a disposable random from the certificate authority, the user does not need to remember a separate password and receives the random number by using the smart phone. It does not save the user's personal information in the database, and it is easy to management of personal information. Only the integration ID needs to be remembered with random number on every time. It doesn't need to use various IDs and passwords if you use this proposed authentication methods.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.10
• /
• pp.5974-5979
• /
• 2014

Lightweight parts with very uniform precision are manufactured by an indent method and the press technique has been improved. Upon assembly with an indent method, a deformation force due to the compressive force occurs between the pin and hole and the contact surface is affected by damage. Therefore, a 3 dimensional model was made using the CATIA program and the damage on the surface contacted with indent was estimated through the ANSYS program in this study. In the analysis result, the maximum load applied at the PCB plate was 21.3 N when the pin goes through the PCB plate. When PCB plate came out of the pin, the maximum load was 19.24 N. As the structural analysis result, the maximum equivalent stress of Pin 1 was 192.96MPa because the maximum stress occurs at Pin 1 among all parts of this study model. By examining the damage property of the contacted indent and applying this study result to the design of real indentation, the damage can be prevented and the durability can be estimated.