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Induction motors are used in various fields, such as technologies of system related with houses and industries. Especially double-cage induction motors are used in a variety of industries because they have high starting torque and high efficiency during rated operation. In the double-cage motor, current flows into the working bar due to the difference in resistance between the starting bar and the working bar. Therefore, performance and efficiency of the motor during the rated operation are determined by size of area and shape of the working bar. In order to increase the efficiency in the region of rated operation, studies, which are change of the working bar’s size of area and shape, have been conducted. However, it is not easy to determine optimistic point because there is a the trade-off relationship between the performance and the size of area. Also, it is tough to manufacture complex shape of the working bar despite the complex shapes can embody tremendous performance. In this paper, size of the area and the shape were never changed, but the working bars are considered rotated position to improve efficiency of the machinery in the rated operation region and analyze the performance as changing of rotation angle of the working bar that is chosen as design variable. A optimistic design which is a 15-kW class double-cage induction motor that can be applicable to submersible pump has been proposed through finite element analysis (FEA) that is based on range of the design variable to optimize the performance and the efficiency.

An interior permanent magnet synchronous motor generally injects adhesive like a bond into the magnet tolerance to prevent vibration between the permanent magnet and the magnet tolerance. In this case, there is a disadvantage that magnet tolerance does not contribute to performance. In this paper, a method to improve the torque density by inserting ferrofluid to utilize magnet tolerance was proposed. When inserting ferrofluid into magnet tolerance, it is important to fix the magnet because it does not use an existing adhesive, and it is important that ferrofluid does not act as a leakage path in the insertion space. In this study, a new rotor configuration using injection plastic that satisfies these considerations was introduced. The analysis was conducted through finite element analysis, and the analysis results and experimental results were compared through dynamo test to verify this study. It was confirmed that no-load back electromotive force increased in the final model through ferrofluid injection.

Nowadays energy efficiency in power electronics has been drawn a more attention as the worldwide energy crisis was raised up. To achieve high efficiency, thermal engineering in the design and construction of power conversion modules (or Intelligent Power Modules) are crucial in their rating and applications because the operation temperature or junction temperature (which is a maximum temperature rise in the die at a given power dissipation) gives strong impacts on reliability, performance and efficiency. A module with a low thermal resistance can afford the operation at the high power densities for the same temperature rise or lower temperatures for fixed power densities. To build an efficient power module having lower thermal resistance, substrate having a high thermal conductivity as well as good electrical isolation and reliability should be selected as a packaging platform. In this paper, the novel substrate technology which is so called ‘Copper Bonded Metal Substrate’ technology has been developed for intelligent power module (IPM) applications. Without the assistance of an adhesive material, the copper is directly bonded to the dielectric layers which have a high thermal conductivity and low-CTE (Coefficient of Thermal Expansion). These properties make CBM substrate technology a strongest contender for a packaging platform in power module applications. Electrical and thermal characteristics of the CBMTM substrate have been investigated as well. Owing to the structural continuity of CBM™ structure, as well as the high thermal conductivity of dielectric layer which is up to ∼5 W/m-K, the retardation of thermal resistance in the interface between the copper layer and base plate has been minimized. And computational simulation and experimental measurement of the thermal resistance of the functional power module which adopt the CBM™ substrate have been conducted. In addition, electrical insulating properties are enough to be affordable for a high voltage operation (over 700 Vrms) of the power modules with a low leakage current (< 300 nA). The obtained results in which CBM™ substrate has high heat dissipating capability and high insulating properties have been proven for CBM™ technology to be suitable for power module applications.

Microchannel plasma devices have been fabricated in a single sheet of aluminum foil, ranging in thickness from 100 to 127 µm, by electrochemical processes. Precisely controlled electrochemical processing enables the integration of 200 microchannels in an area as large as 42 cm2. The width and length of each microchannel in the device is ∼75 µm and 7 cm, respectively. All the electrodes and interconnects along the microchannels are patterned by standard photolithography, and they are encapsulated by nanoporous Al 2 O 3 , acting as the dielectric barrier layer for a capacitive discharge. An entire sheet of aluminum is converted into Al 2 O 3 with the exception of thin aluminum electrodes lying in each barrier rib structure and electrically isolated from each other. Individual electrodes can be driven by applying an external power input between two neighboring electrodes. The capacitance and power consumption of the device are decreased by more than 50% relative to the previously reported Al/Al 2 O 3 microplasma devices of the same area.1,2

Focusing on multicast transmission in a CDMA based 3G system, we address a soft-combine zone configuration problem. The problem is to find a limited number of cells supporting soft-combine such that each cell has at least one neighboring cell, which also supports soft-combine, while the sum of traffic demands of the selected cells is maximized. We show that this problem is NP-hard, introduce an integer programming formulation, and develop an algorithm generating soft-combine zone configurations. Reflecting the dynamic traffic demands change, an efficient structure for dynamic reconfiguration of soft-combine zone is proposed.

For the first time, a fully 3-dimensional (3-D) flash cell with recessed channel and cylindrical floating gate is successfully integrated with 65nm MLC NOR flash technology. Key process technologies to achieve the novel cell structures are shown to be highly feasible. Superior scalability and comparable device characteristics including V th distribution and tunnel oxide reliability are proved through 512Mb full chip integration. Intrinsic immunity on the short channel effect of this 3-D cell opens a promising path for the continued scaling of the floating gate flash memories for 65nm and beyond

Summary form only given. Flexible planar light sources are becoming a key technology for several applications such as portable displays, flexible illumination sources and biomedical applications. In particular, ultraviolet emission wavelengths between 250 and 400 nm are of great importance in biomedical applications. In this presentation, we report the fabrication and characteristics of arrays of microplasma devices having Al2O3 encapsulated metal electrodes which are designed for operation at atmospheric gas pressure. Following the growth of a thin layer of nanostructured Al2O3 on Al foil by a multistep electrochemical process, a film of SiO2 is deposited to bring the total dielectric thickness to 5 mum. Because the overall thickness of the device structure is 60-100 mum, an array of devices is fully flexible and is readily scalable in surface area. When driven by a sinusoidal waveform having a frequency of 20 kHz, the operating voltage for 600 torr of Ne is nominally 200 V (RMS). Also, the variation in emission intensity across the array is less than 10%. Several wavelength regions in the UV are accessible through the choice of molecular emitters. The optical and electrical characteristics of large scale arrays (tens of cm2) that are vacuum-sealed and flexible will be described

In this paper, the effects of a lumped element on a DGSI (Defected Ground Structure with Islands), which consists of some islands around the microstrip signal line on the upper plane, are investigated. In order to demonstrate the effects of the lumped element which is placed at the islands section on the upper plane, a parallel resonator with the dumbbell-shaped DGSI is proposed and implemented. A chip resistor and capacitor are chosen as lumped elements for the verification. Experimental results show that the Q-factor and resonant frequency of the proposed DGSI can be controlled directly by using the external lumped element.

Summary form only given. The efficient generation of ultraviolet in microscopic spatial scale is becoming significant as a key technology in applications such as displays, microchemical reactors and biomedical diagnosis or treatment. The microcavity plasma device is one promising candidate for miniaturized UV sources having high luminance and stability. In particular, we have recently observed that the extraordinary specific power loadings afforded by these devices in nanoliters volumes allow for stable glow discharge to be produced in a wide variety of gases and vapors including air at atmospheric pressure. In this presentation, we report the fabrication and performance of microdischarge arrays having electrodes encapsulated by a nanoporous dielectric. The device is a multilayer structure comprising Al foil electrodes and nanoporous Al2O3 as the dielectric. Having microcavities with diameters of 100-200 mum, these devices are excited by AC and generate uniform, spatially uniform glow discharges in Ar/N2 gas mixtures at total pressures of 400-800 torr. A 3times3 array of microdischarge devices, each having a microcavity diameter of 100-200 mum dia., also produce stable glow discharges for operating voltages (peak-to-peak) in the range of 800-1200 V at 400 torr of total pressure. In this voltage range, the array exhibits a linear increase in the plasma differential resistance and the total UV output intensities increases beyond several mW-cm-2

A system network-based instrument is trend in order to include an active function in a currently industrial field. However, there are many different kinds of the computing environments that industrial instruments are applying, and the system that possessed a networking function is very expensive. A Java to execute in an independent computing environment has enough advantages to establish environment requested in an industrial field. In this paper, we propose the active measurement diagnosis system that can compose a Java-based industrial embedded computing environment. A Java platform of a proposed system is including a module and Java API used in an industrial field. This system can easily integrate different execution environment between each target systems. In this way, an active measurement diagnosis system simplifies system structure and equally makes a computing environment between systems.

Focusing on multicast transmission in a CDMA based 3G system, we address a soft-combine zone configuration problem. The problem is to find a limited number of cells supporting soft-combine such that each cell has at least one neighboring cell, which also supports soft-combine, while the sum of traffic demands of the selected cells is maximized. We show that this problem is NP-hard, introduce an integer programming formulation, and develop an algorithm generating upper and lower bounds for the soft-combine zone configuration problem, which enables the optimal zone configuration easy to solve in real-time fashion