• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1451-1455
• /
• 2007

MAGLEV(Magnetic Levitation) with Middle-low speed be classified as a kind of LRT(Light Rail Transit) in KOREA. Also this vehicle has adopted LIM propulsion method. The MAGLEV has adopted LIM type in operational or developing model in the world. The power rail of LIM is very similar with the 3th rail of LRT in the functional property but the structure and shape of power rail is different with that. WE have to search the optimal power rail system for Korean MAGLEV vehicle. In this paper, we suggest the conceptual design and direction of design for power rail of Korean MAGLEV developing.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.556-559
• /
• 2004

This study was aimed to verify the acceptable contact force between power collector and 3rd rail type conductor rail for the Korean standardized rubber-tired AGT light rail vehicle. The power collector was designed and manufactured to satisfy the Korean standardized Specifications of the rubber-tired AGT light rail vehicle. Based on the dynamic behavior, contact force variation and interruption in the worst installation tolerance of the conductor rail, its initial contact force was set up. With rotary disk type equivalent test apparatus with circular conductor rail, the interruptions were measured. As the results, acceptable contact force was proposed to ensure power collection stability.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1341-1344
• /
• 2005

This study was aimed to verify the acceptable contact force between power collector and 3rd rail type conductor rail for the Korean standardized rubber-tired AGT light rail vehicle. The power collector was designed and manufactured to satisfy the Korean standardized Specifications of the rubber-tired AGT light rail vehicle. Based on the dynamic behavior, contact force variation and interruption in the worst installation tolerance of the conductor rail, its initial contact force was set up. At the test track for the Korean standardized rubber-tired AGT light rail vehicle, interruptions, stresses, vibrations, and contact force variations were measured. As the results, initial contact force was verified to ensure power collection stability.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.49 no.2
• /
• pp.39-46
• /
• 2012

The newly designed sense amplifier in this paper has rail-to-rail input range achieving low power consumption. Reducing static power consumption generated due to DC path to ground is key element for low power consumption in this paper. The proposed sense amplifier performs power-saving operation using negative feedback circuit that controls the current flow with the newly added PMOS input terminal. As a simulation result, the proposed sense amplifier consumed about over 50 % efficiency of the average power consumed by the typical Rail-to-Rail sense amplifier.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.7
• /
• pp.96-102
• /
• 2014

In this paper, we proposed new dual-rail data encoding that mixed 4-phase handshaking protocol and 2-phase handshaking protocol for asynchronous system design to reduce signal activities and power consumption. The dual-rail data encoding 4-phase handshaking protocol should leat to much signal activities and power consumption by return to space state. Ideally, the dual-rail data encoding 2-phase handshaking protocol should lead to faster circuits and lower power consumption than the dual-rail 4-phase handshaking protocol, but can not designed using standard library. We use a benchmark circuit that contains a multiplier block, an adder block, and latches to evaluate the proposed dual-rail data encoding. The benchmark circuit using the proposed dual-rail data encoding shows an over 35% reduction in power consumption with 4-phase dual-rail data encoding.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.413-414
• /
• 2006

This study was aimed to verify the stable interruption characteristics between power collector and 3rd rail type conductor rail for the Korean-standardized rubber-tired AGT light rail vehicle. At the test track for the Korean-standardized rubber-tired AGT light rail vehicle, interruption ratios, stresses, vibrations, and contact force variations were measured by test conditions, having various train speed. As the results, it was verified that developed 3rd rail type conductor maintains interruption characteristics, which can supply stable electric power.

• Structural Engineering and Mechanics
• /
• v.63 no.5
• /
• pp.659-667
• /
• 2017

Rail support failure is inevitably subjected to track geometric deformations. Due to the randomness and evolvements of track irregularities, it is naturally a hard work to grasp the trajectories of dynamic responses of railway systems. This work studies the influence of rail fastener failure on dynamic behaviours of wheel/rail interactions and the railway tracks by jointly considering the effects of track random irregularities. The failure of rail fastener is simulated by setting the stiffness and damping of rail fasteners to be zeroes in the compiled vehicle-track coupled model. While track random irregularities will be transformed from the PSD functions using a developed probabilistic method. The novelty of this work lays on providing a method to completely reveal the possible responses of railway systems under jointly excitation of track random irregularities and rail support failure. The numerical results show that rail fastener failure has a great influence on both the wheel/rail interactions and the track vibrations if the number of rail fastener failure is over three. Besides, the full views of time-dependent amplitudes and probabilities of dynamic indices can be clearly presented against different failing status.

• Korean Journal of Agricultural Science
• /
• v.49 no.1
• /
• pp.151-162
• /
• 2022

This study was conducted to develop a rail-type boom sprayer, performing safe spraying with improved ergonomic postures during pesticide spraying of agro-photovoltaic power system. The sprayer was designed to reduce labor cost and to be safe from pesticide exposure, and was analyzed through a comparison with a conventional spray method. The rail-type boom sprayer, consisted of a self-propelled spray and hose winder, hose, and boom sprayer parts, was designed to automatically pull and spray in the vertical and horizontal directions. The performance of the sprayer for an agro-photovoltaic power system was appropriate. From the analysis of postures with the Ovako Working posture Analysis System (OWAS), Rapid Entire Body Assessment (REBA), and Rapid Upper Limb Assessment (RULA) methods, the musculoskeletal risk factors to the body using the rail-type boom sprayer were less than those with the conventional power sprayer. In addition, the possibility of pesticide poisoning was reduced compared to the conventional power sprayer. The working capacity with the rail-type boom sprayer was more than five times greater, compared with the conventional power sprayer. After performing pesticide spraying with the rail-type boom sprayer, the labor cost was reduced to 42,750 won·yr^-1, which was 90% (402,750 won·yr^-1) less than the cost with the use of a conventional power sprayer (445,500 won·yr^-1).

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.832-836
• /
• 2004

This study was aimed to establish the acceptable contact force range between power collector and 3rd rail type conductor rail, and ramp slope for the Korean standardized rubber-tired AGT light rail vehicle. Dynamic behavior of the power collector, contact force variation and interruption in operation, were analyzed in the worst installation tolerance and various ramp slope of the conductor rail. The power collector was designed and manufactured to satisfy the Korean Standardized Specifications of the rubber-tired AGT light rail vehicle.

• ETRI Journal
• /
• v.29 no.6
• /
• pp.785-793
• /
• 2007

In this paper, we present an integrated rail-to-rail fully differential operational transconductance amplifier (OTA) working at low-supply voltages (1.5 V) with reduced power consumption and showing high DC gain. An embedded adaptive biasing circuit makes it possible to obtain low stand-by power dissipation (lower than 0.17 mW in the rail-to-rail version), while the high DC gain (over 78 dB) is ensured by positive feedback. The circuit, fabricated in a standard CMOS integrated technology (AMS 0.35 ${\mu}m$), presents a 37 V/${\mu}s$ slew-rate for a capacitive load of 15 pF. Experimental results and high values of two quality factors, or figures of merit, show the validity of the proposed OTA, when compared with other OTA configurations.