• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.6
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• pp.565-575
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• 2009

A forklift (also called a lift truck) is a powered industrial truck that is used to lift and transport materials. It has become an indispensable piece of equipment in manufacturing and warehousing operations. The modem forklift is equipped with automatic transmission to meet the requirement of loading and easy operation of the vehicle. This paper proposes the design of TECU(Transmission Electronic Control Unit) which is applied to PSD322-Axle transmission. Garofalo's control technique is generally used to the automatic transmission. We consider the work quality and market requirement that does not want to control engine throttle. This paper proposes new controller system which guarantees efficient speed changes with simple system. This new system does not control the engine throttle spontaneously. But it has the load of engine and vehicle as a maximum disturbance. The scope of the disturbance is limited to the stoll area of the torque converter. This paper proposes a ideal control commander that converges relative velocity of the input and ouput of a clutch into a zero. We design linear controller to execute the idea control commander. We applied the control algorithm to the forklift of PSD322-Axle type and the performance of this controller was verified.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.1
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• pp.55-60
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• 2010

For battery-powered device applications, which grow rapidly in the electronic market today, low-power becomes one of the most important design issues of CMOS VLSI circuits. A multi-VDD system, which uses more than one power-supply voltage in the same system, is an effective way to reduce the power consumption without degrading operating speed. However, in the multi-VDD system, level converters should be inserted to prevent a large static current flow for the low-to-high conversion. The insertion of the level converters induces the overheads of power consumption, delay, and area. In this paper, we propose a new level converter which can provide the level up/down conversions for the various input and output voltages. Since the proposed level converter uses only one power-supply voltage, it has an advantage of reducing the complexity in physical design. In addition, the proposed level converter provides lower power and higher speed, compared to existing level converters.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.9
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• pp.2057-2065
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• 2014

New business The e-book industry is creating a convergence of ICT and printing culture. Even so, the system changes is not great in Korea. Global market players are going to creating a membership or community-type business model to take advantage of the terminal, platform, network, but the creative content production in Korea is limited. Since the discussion is limited to such devices or network services most, we suggest the possibility of modeling a multi-faceted. And the development of technology and services platform content is also important as a strategic approach to the development of the e-book industry. Most of all, we propose the application of content, technologies and services are developed.

• The KIPS Transactions:PartA
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• v.19A no.1
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• pp.17-22
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• 2012

The demand of high performance processor is soaring due to the extending of mobile and small electronic device market. CGRA(Coarse Grained Reconfigurable Architecture) is the processor satisfying both of performance and low-power demands and a great alternative of ASIC that can be reconfigured. This paper presents a novel low-power mapping algorithm that optimizes the number of used computation resource in the mapping phase by considering data transfer time. Compared with previous mapping algorithm, ours reduce energy consumption by up to 73%, and 56.4% on average.

• Journal of Power Electronics
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• v.2 no.4
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• pp.268-277
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• 2002

Power electronics is an interdisciplinary area that is interstitial to all of the major disciplines of electrical engineering including power, electronics and control. Today, the covering field of power electronics has more widely spread out with the help of ever evolving microelectronics and computer science. Whereas, in Japan the tendency is becoming remarkable nowadays that science, especially "mathematics" and "hardware work", are falling into disfavor with the young people. For these reasons, it has become a very important problem to find out "what are the truest essentials of power electronics\ulcorner" and "How to give students incentives to learn power electronics\ulcorner " from an educational point of view In under-graduate and graduate courses in universities. On the other hand, the power electronics engineers in companies are always required to comply with the ever changing trend of global and open market. However, it takes long time to cultivate their skills. Against the background, "The Cooperative Research Committee on Education of Power Electronics" was established in the IEEJ Industry Applications Society during 2000-2001. The present status of the power electronics education in Japan is surveyed in this paper, and some problems with remedy are pointed out based on the discussions performed in the committee.sed on the discussions performed in the committee.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1337-1345
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• 2018

The reliability of power transmission and distribution depends up on the consistency of insulation in the high voltage power transformer. In recent times, considering the drawbacks of conventional mineral oils such as poor biodegradability and poor fire safety level, several research works are being carried out on natural ester based nanofluids. Earlier research works show that sunflower oil has similar dielectric characteristics compared with mineral oil. BIOTEMP oil which is now commercially available in the market for transformers is based on sunflower oil. Addition of nanofillers in the base oil improves the dielectric characteristics of liquid insulation. Only few results are available in the literature about the insulation characteristics of nano modified natural esters. Hence understanding the influence of addition of nanofillers in the dielectric properties of sunflower oil and collecting the database is important. Considering these facts, present work contributes to investigate the important characteristics such as partial discharge, lightning impulse, breakdown strength, tandelta, volume resistivity, viscosity and thermal characteristics of $SiO_2$ nano modified sunflower oil with different wt% concentration of nano filler material varied from 0.01wt% to 0.1wt%. From the obtained results, nano modified sunflower oil shows better performance than virgin sunflower oil and hence it may be a suitable candidate for power transformer applications.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.8
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• pp.19-23
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• 2005

The target of this research is a design of constant and high efficiency driving system for a low pressure UV lamp. An UV lamp system is one of wide range electrical equipments for semiconductor manufacturing and sterilization, etc... It is essential the technique of constant output for high added value device. A design target of driving system for low pressure UV lamp of conversion efficiency is 90[%], UV lamp of output stability within ${\pm}7.5[%]$, and lamp power is over 200[W]. The results meet the target of this study well, and have a benefit of domestic market occupation and enable to export. And if protection circuits were developed, it increases the stability of a electronic ballast for UV lamps.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.2
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• pp.41-46
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• 2015

The demand on low power and high performance system is soaring due to the extending of mobile and small electronic device market. The 3D die-stacking technology is widely studying for next generation integration technology due to its high density and low access time. We proposed the 3D die-stacked DRAM including a reconfigurable accelerator in a logic layer of DRAM. Also we discuss and suggest a cache-based local memory for a reconfigurable accelerator in a logic layer. The reconfigurable accelerator in logic layer of 3D die-stacked DRAM reduces the overhead of data management and transfer due to the characteristics of its location, so that can increase the performance highly. The proposed system archives 24.8 speedup in maximum.

• The Journal of Information Technology
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• v.3 no.3
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• pp.39-55
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• 2000

Internet Trade is the new type of business transaction, which sells and advertises the product and services by using the Internet, which is spreaded rapidly to the world. Under these circumstance, our country should discuss the proper position and role as the center in the trade amount in the world trade market, and face the irresistible changes of trade environment. First, in the institution and legal aspect. Second, the price payment system of the internet trade. Third, the so-called infra construction, the physical sector for activating the internet trade, the comprehensive plan of super-highway information communication net work by the government authorities is expected to be promoted. There is no perfect solution that internet trade could be completely done in front of monitor and will be solved one by one along with the development of electronic commerce. At last, the government's and industry's joint positive concern and participation in the rapidly changing new world trade trends of internet trade is expected fit for our position in the world.

• Korean Journal of Materials Research
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• v.15 no.9
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• pp.613-619
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• 2005

The ever increasing popularity and acceptance in the market place of portable systems, such as cell phones, PDA, notebook PC, etc., are fueling effects in further miniaturizing and lowering power consumption in these systems. The dynamic power consumption due to the CPU activities and the static power consumption due to leakage currents are two major sources of power consumption. Smaller devices and a lower de voltage lead to reducing the power requirement, while better insulation and isolation of devices lead to reducing leakage currents. All these can be harnessed in the SOI (silicon-on-insulator) technology. In this study, the key aspects of the SOI technology, mainly device electrical properties and device processing steps, are briefly reviewed. The interesting materials issues, such as SOI structure formation and SOI wafer fabrication methods, are then surveyed. In particular, the recent technological innovations in two major SOI wafer fabrication methods, namely wafer bonding and SIMOX, are explored and compared in depth. The results of the study are nixed in that, although the quality of the SOI structures has shown great improvements, the processing steps are still found to be too complex. Between the two methods, no clear winner has yet emerged in terms of the product quality and cost considerations.