• International Journal of Automotive Technology
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• v.7 no.4
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• pp.459-468
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• 2006

The objective of this paper is the development of the forward-looking dynamic simulation model of a hybrid electric vehicle(HEV) for a fuel economy study. The specification of the vehicle is determined based on two factors, engine peak power to curb weight ratio and specific engine power. The steady state efficiency models of the powertrain components are explained in detail. These include a spark ignition direct injection(SIDI) engine, an integrated starter alternator(ISA), and an infinitely variable transmission(IVT). The paper describes the integration of these models into a forward facing dynamic simulation diagram using the AMESim environment. Appropriate vehicle and driver models have been added and described. The controller was designed in Simulink and was combined with the physical powertrain model by the co-simulation interface. Finally, the simulation results of the HEV are compared with those of a baseline vehicle in order to demonstrate the fuel economy potential. Results for the vehicle speed error and the fuel economy over standard driving cycles are illustrated.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.2
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• pp.84-89
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• 2013

In this paper, we propose interface circuits for reducing power consumption and EMI when sequences of data from LCD controller to LCD driver IC by transmitting two bit data during one clock period. The proposed circuits are operated in current mode, which is different from conventional voltage-mode signaling techniques, and also employ threshold technique of Modified-LVDS(Low Voltage Differential Signaling) method. We have simulated the proposed circuits using H-SPICE tool for performance analysis of the proposed method. The simulation results show that the proposed circuits provide a faster transmission speed and stronger noise immunity than the conventional LVDS circuits. It might be suitable for the real-time transmission of huge image data in LCD system.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.2817-2824
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• 1994

A torque split type multi-pass CVT(MPC) system consiting of CVT and planetary gear train with 4 clutches was suggested to overcome the inherent inferior acceleration performance of CVT. Also, a shifting algorithm of MPC was suggested for the two driving modes : (1) power mode and (2) economy mode. By using the shifting algorithm and the MPC vehicle dynamic model, numerical simulations were performed to estimate the performance of the MPC vehicle. Simulation results showed that comparing the performance of the conventional 4-speed automatic transmission, an improvement in acceleration can be obtained by MPC for the power mode and 31% improvement in fuel economy for the economy mode.

• Proceedings of the KSRS Conference
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• v.2
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• pp.784-787
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• 2006

Dual-polarized transmission is one of the effective methods to transmit such a high speed data thanks to two independent channel leads to the orthogonal feature between RHCP (Right-Hand Circular Polarization) and LHCP (Left-Hand Circular Polarization). However, in practical case, the transmitted signal by RHCP polarized antenna in satellite can be occurred at the output port of LHCP polarized antenna in ground station, vice versa. XPD (Cross-Polarization Discrimination) is the ratio of the signal level at the output of a receiving antenna that is nominally co-polarized to the transmitting antenna to the output of a receiving antenna of the same gain but nominally orthogonally polarized to the transmitting antenna. In this paper, the detailed estimation of XPD within the interface between satellite and ground station is written and the influence of XPD to link performance is also described.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.324-327
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• 2002

For the characterization of arbitrary shaped printed circuit board, lossy transmission line grid model based on SPICE netlist and analytical plane model based on the segmentation method are proposed in this paper. Two methods are compared with an arbitrary shaped power/ground plane. Furthermore, design considerations for the complete power distribution network structure are discussed to ensure the maximum value of the PDN impedance is low enough across the desired frequency range and to guide decoupling capacitor selection.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1995.03a
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• pp.34-39
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• 1995

To reduce the shock in shifting the clutches and the brakes in automatic transmission have to be connected smoothly and disconnected rapidly. It is PCSV(Pressure Control Solenoid Valve) that play this role of automatic transmission. In this paper there were two steps in the analysis of the PCSV. The first step was modeling the elctromagnet by the permeance method. The second step was modeling the hydraulic circuit by the pressure differential equation. In addition to this modeling a experiment was performed and the commercial package program was used in order to justify modeling. The result of modeling coincide with the result of experiment and commercial package program. As a result this modeling is usable in analysis of dynamic characteractic of the PCSV.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.704-709
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• 1994

The insertion loss is the measured change in power flux at a specified receiver, when the acoustic transmission path between it and the source is modified by the insertion of silencer element. Such measurements have clear and valid physical meaning particularly if the source impedance remains while the transmission path is altered. When the invarient condition is satisfied, the insertion loss is given by the ratio of the acoustic pressure in upstream to that in downstream of the silencer, and that of the particle velocity. The measurement is consisted of using an adaptation of the two microphone method to obtain the complex amplitude of the sound in upstream tube as well as in downstream tube of the silencer. Examples of the data, reduced and presented in terms of the pressure ratio and particle speed ratio, are compared with the theoretical calculations.

• Progress in Superconductivity
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• v.3 no.1
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• pp.17-22
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• 2001

Practical implementation of the SFQ technology in most application requires more than single-chip-level circuit complexity. Multiple chips have to be integrated with a technology that is reliable at cryogenic temperatures and supports an inter-chip data transmission speed of tens of GHz. In this work, we have studied two basic issues in building large RSFQ circuits. The first is the reliable inter-chip SFQ pulse transfer technique using Multi-Chip-Module (MCM) technology. By noting that the energy contained in an SFQ pulse is less than an attojoule, it is not very surprising that the direct transmission of a single SFQ pulse through MCM solder bump connectors can be difficult and an innovative technique is needed. The second is the recycling of the bias currents. Since RSFQ circuits are dc current biased the large RSFQ circuits need serial biasing to reduce the total amount of current input to the circuit.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1251-1251
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• 2001

The routine analysis of milk chemical components is of major importance both for the management of animals in dairy farms and for quality control in dairy industries. NIRS technology is an analytical technique which greatly simplifies this routine. One of the most critical aspects in NIRS analysis of milk is sample preparation and analysis modes which should be fast and straightforward. An important difficulty when obtaining NIR spectra of milk is the high water content (80 to 90%) of this product, since water absorbs most of the infrared radiation, and, therefore, limits the accuracy of calibrating for other constituents. To avoid this problem, the DESIR system was set up. Other ways of radiation-sample interaction adapted for liquids or semi-liquids exist, which are practically instantaneous and with limited or null necessity of sample preparation: Transmission and Folded Transmission or Transflectance. The objective of the present work is to compare the precision and accuracy of milk calibration equations in two analysis modes: Reflectance (dry milk) and Folded Transmission (liquid milk). A FOSS-NIR Systems 6500 I spectrophotometer (400-2500 nm) provided with a spinning module was used. Two NIR spectroscopic methods for milk analysis were compared: a) folded transmission: liquid milk samples in a 0.1 pathlength sample cell (ref. IH-0345) and b) reflectance: dried milk samples in glass fibre filters placed in a standard ring cell. A set of 101 milk samples was used to develop the calibration equations, for the two NIR analysis modes, to predict casein, protein, fat and dry matter contents, and 48 milk samples to predict Somatic Cell Count (SCC). The calibrations obtained for protein, fat and dry matter have an excellent quantitative prediction power, since they present $r^2$ values higher than 0.9. The $r^2$ values are slightly lower for casein and SCC (0.88 and 0.89 respectively), but they still are sufficiently high. The accuracy of casein, protein and SCC equations is not affected by the analysis modes, since their ETVC values are very similar in reflectance and folded transmission (0.19% vs 0.21%; 0.16% vs 0.19% and 55.57% vs 53.11% respectively), Lower SECV values were obtained for the prediction of fat and dry matter with the folded transmission equations (0.14% and 0.25% respectively) compared to the results with the reflectance ones (0.43% and 0.34% respectively). In terms of accuracy and speed of analytical response, NIRS analysis of liquid milk is recommended (folded transmission), since the drying procedure takes 24 hours. However, both analysis modes offer satisfactory results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.4A
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• pp.219-226
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• 2012

We investigated the performance of a visible light communication (VLC) transceiver applicable to both of illumination and wireless communication. we considered the visibility of VLC, the easy connection for wireless communication and high-speed transmission and implemented VLC transceiver based on edge-emitting laser diode and silicon photodiode. The proposed VLC transceiver is designated to operate in a full duplex mode at high speed of 120 Mbit/s. The shielding method that is employed as a means to reduce the light cross coupling effect inside the VLC transceiver is proposed and its performance is experimentally measured. We also applied optical antenna to have the larger angle of field of view (FOV) to novel structure of VLC transceiver and examined and analyzed their bit error rate performance, photometric result with respect to the transmission distance, the coverage range and the tilt degree as transmission link characteristic between two transceivers without optical antenna and with optical antenna.