• Journal of Power System Engineering
• /
• v.7 no.3
• /
• pp.61-68
• /
• 2003

Steering characteristics is an important factor in the evaluation of vehicle quality. To estimate steering characteristics in the vehicle conceptual design stage, vehicle dynamics simulation methods are very efficient. However, it is often difficult to simulate vehicle dynamics for the specific driving scenarios in open-loop driving environment. An efficient driver-in-the-loop vehicle model will be efficient for this job. A good tire model is also very important for the accurate vehicle dynamics simulation. In this research, a driver model is used to simulate vehicle steering dynamics for a 8-dof vehicle model with STI(Systems Technology, Inc.) tire model. For the demonstration of this model, a SUV(sports utility vehicle) and a sedan were simulated.

• Journal of Communications and Networks
• /
• v.4 no.2
• /
• pp.97-101
• /
• 2002

Based on their shift and scale orthogonality properties, scaling and wavelet functions may be used as signaling functions having good frequency localization as determined by the fractional-out-of-band power (FOOBP). In this paper, application of Daubechies' wavelet and scaling functions as baseband signaling functions is described, with a focus on finding discretely realizable pulse-shaping transfer function circuits whose outputs approximate scaling and wavelet functions when driven by more conventional digital signaling waveforms. It is also shown that the inter-symbol interference (ISI) introduced by the approximation has negligible effect on the performance in terms of signal-to-noise ratio (SNR). Moreover, the approximations are often more bandwidth efficient than the original wavelet functions. These waveforms thus illustrate an example solution of a tradeoff between residual ISI and bandwidth efficiency as a signal design problem.

• Proceedings of the KIEE Conference
• /
• 2006.04a
• /
• pp.165-167
• /
• 2006

In this paper we present a new-generation sensor network processor which is not optimized in circuit level, but in system architecture level. The new design build on a conventional processor architecture, improving the design by focusing on application oriented specification, ISA, and micro-architectural optimization that reduce overall design size and advance energy-per-instruction. The design employs harvard architecture, 8-bit data paths, and an compact 19 bit wide RISC ISA. The design also features a unique interrupt handler which offloads periodical monitoring jobs from the main part of CPU. Our most efficient design is capable of running at 300 KHz (0.3 MIPS) while consuming only about few pJ/instruction.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.9 no.4
• /
• pp.249-256
• /
• 2009

As a wireless handset deals with multiple application standards concurrently, RF transmitters and power amplifiers are required to be more power efficient and reconfigurable. In this paper, we review the recent advances in the design of the power amplifiers and transmitters. Then, the systematic design approaches to improve the performance with the digital baseband signal processing are introduced for the next generation mobile handset.

• Journal of Advanced Marine Engineering and Technology
• /
• v.40 no.5
• /
• pp.429-436
• /
• 2016

Currently, many studies on green ships are under way. Fuel cell (FC) ships are of interest as future low-emission, fuel-efficient vessels. In this paper, a hybrid power management system for an FC ship was designed. The system consists of an FC, a battery, a unidirectional DC/DC converter, a bidirectional DC/DC converter, a filter, an inverter, and a propulsion component. To design the system, we analyze electric sources and converters, and create PLECS models of hybrid power management system. Then, we check the cold start sequence and perform a simulation to understand the characteristics of the hybrid power management system in an FC ship.

• Journal of electromagnetic engineering and science
• /
• v.16 no.1
• /
• pp.52-56
• /
• 2016

This paper suggests a class-F power amplifier with split open-end stubs to provide a broadband high-efficiency operation. These stubs are designed to have wide bandwidth by splitting wide open-end stubs into narrower stubs connected in shunt in an output matching network for class-F operation. In contrast to conventional wideband class-F designs, which theoretically need a large number of matching lines, this method requires fewer transmission lines, resulting in a compact circuit implementation. In addition, the open-end stubs are designed with slant ends to achieve additional wide bandwidth. To verify the suggested design, a 10-W class-F power amplifier operating at 1.7 GHz was implemented using a commercial GaN transistor. The measurement results showed a peak drain efficiency of 82.1% and 750 MHz of bandwidth for an efficiency higher than 63%. Additionally, the maximum output power was 14.45 W at 1.7 GHz.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.1
• /
• pp.124-130
• /
• 2011

In this paper, We design and implementation of Self-Charging Module for charging to battery which obtaining the environment inergy such as solar energy. The power chared battery through the charging module send to sensor node. And implementation of System Activation Module(SAM) based on ID system and Dynamic Power Management Module(DPM) with SPO(Self Power Off). This system consume power only communication between the sensor nodes. We verification this system by implementing the high efficiency poweer management system.

• Journal of Electrical Engineering and Technology
• /
• v.2 no.1
• /
• pp.68-80
• /
• 2007

This paper covers switched reluctance generator (SRG) and its comparison with induction and synchronous machines for distributed generation. The SRG is simple in design, robust in construction, and fault tolerant in operation; it can also withstand very high temperatures. However, the performance and cost of the SRG power electronics driver are highly affected by the topology and design of the converter. IGBT and MOSFET based converters are not suitable for very high power applications. This paper presents thyristor-based resonant converters which are superior candidates for very high power applications. Operations of the converters are analyzed and their characteristics and dynamics are determined in terms of the system parameters. The resonant converters are capable of handling high currents and voltages; these converters are highly efficient and reliable as well. Therefore, they are suitable for high power applications in the range of 1MW or larger for distributed generation.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.15 no.6
• /
• pp.761-769
• /
• 2012

In this paper, we propose a low-power design strategy to minimize energy-consumption for surveillance and reconnaissance sensor networks. The sensor network consists of many different nodes with various operations such as target detection, packet relay, video monitoring, changing protocols, and etc. Each sensor node consists of sensing, computing, communication, and power components. These components are integrated on a single or multiple boards. Therefore, the power consumption of each component can be different on various operation types. First, we identified the list of components and measured power consumption for them from the first prototype nodes. Next, we focus on which components are the main sources of energy consumption. We propose many energy-efficient approaches to reduce energy consumption for each operation type.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2002.05a
• /
• pp.867-872
• /
• 2002

The seismic design from the underground structures with the ground structures differently relative acceleration of ground and structure for, that period ci it was a condition where the recognition against the seismic design of the underground structure is insufficient because the decease damage does not very to that extent. Analysis result, earthquake hour section power increase one that price smiles from one part and when it applies a regular design hour safety rate 20%, seismic efficiency level satisfaction is it becomes feed with the fact that it will be able to augment the efficient characteristic of design.