Education of Power Electronics in Japan

Matsui, Mikihiko,Ueda, Akiteru,Oguch, Kuniomi The Korean Institute of Power Electronics 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.4

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.

A Novel Interactive Power Electronics Seminar (iPES) Developed at the Swiss Federal Institute of Technology (ETH) Zurich

Drofenik, Uwe,Kolar, Johann W. The Korean Institute of Power Electronics 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.4

This paper introduces the Interactive Power Electronics Seminar - iPES - a new software package for teaching of fundamentals of power electronic circuits and systems. iPES is constituted by HTML text with Java applets for interactive animation, circuit design and simulation and visualization of electromagnetic fields and thermal issues in power electronics. It does comprise an easy-to-use self-explaining graphical user interface. The software does need just a standard web-browser, i.e. no installations are required. iPES can be accessed via the World Wide Web or from a CD-ROM in a stand-alone PC by students and professionals. Due to the underlying software technology iPES is very flexible and could be used for on-line learning and could easily be integrated into an e-learning platform. The aim of this paper Is to give an introduction to the iPES-project and to show the different areas covered. The e- learning software is available at no costs at $\underline{www.ipes.ethz.ch}$ in English, German, Japanese, Korean, Chinese and Spanish. The project is still under development and the web page is updated in about 4 weeks intervals.

Software-based single-node multi-GPU systems for interactive display wall

Kim, Inhyeok,Kim, Junghan,Park, Jonggyu,Eom, Young Ik Institute of Electrical and Electronics Engineers 2017 IEEE transactions on consumer electronics Vol.63 No.2

<P>A display wall, one of the multiple display environments (MDEs), has been widely adopted in various fields including consumer electronics. Conventional display walls are constructed by utilizing cluster-based systems where multiple displays are connected via multiple cluster nodes. However, cluster-based systems have suffered from communication overheads among the cluster nodes when they provide interaction features and run diverse applications. This paper proposes a software-based single-node multi-GPU system for interactive display walls. The proposed system allows multiple GPUs in a single-node system to connect multiple displays, by providing an individual compositor for each GPU in the system. This paper also analyzes memory management models of multi-GPU systems and compositing overheads for multiple displays. Experimental results show that the FPS (frames per second) of the proposed system outperforms that of the conventional system by up to 1.36x, reducing copy overheads among the GPUs by efficient memory management and distributing compositing overheads to multiple GPUs.</P>

Sensorized Surgical Forceps for Robotic-Assisted Minimally Invasive Surgery

Kim, Uikyum,Kim, Yong Bum,So, Jinho,Seok, Dong-Yeop,Choi, Hyouk Ryeol Institute of Electrical and Electronics Engineers 2018 IEEE transactions on industrial electronics Vol.65 No.12

<P>A novel force-sensing mechanism for surgical robotic systems is required for further innovation of robotic-assisted minimally invasive surgery (RMIS). In this paper, novel sensorized surgical forceps are presented with five-degree-of-freedom (5-DOF) force/torque (F/T) sensing capability: a grasping force, a 3-DOF manipulating force, and a rotational torque acting at the forceps. Two compact 3-DOF force sensors are integrated into the proximal region on two jaws of the forceps to measure 5-DOF F/T. The forceps also present important advantages for actual use in RMIS, such as miniaturization, compatible configuration to various shapes of surgical forceps, and packaged sensor electronics. In this study, the forceps are designed and manufactured at a low cost and are even disposable. To evaluate the forceps in a surgical robotic environment, the instrument is installed in a surgical robot, named S-Surge. In the environment, the 5-DOF F/T sensing capability is evaluated through comparison with reference sensors.</P>

Schottky Barrier in Organic Transistors

Xu, Yong,Sun, Huabin,Noh, Yong-Young Institute of Electrical and Electronics Engineers 2017 IEEE transactions on electron devices Vol.64 No.5

<P>Organic FETs (OFETs) are essential devices in future flexible electronics. Yet, a crucial issue associated with electronic contact is still unsolved and our fundamental understanding remains very limited. Unlike many other previous reports talking about the contact resistance, in this paper, we specifically discuss its major root: the Schottky barrier, by comparison of the conventional metal-silicon contacts, and the unconventional metal-organic contacts, where the special features in OFETs are underlined. We not only examine the basics of the Schottky barrier but also the extrinsic effects as well as the characterization methods. The key factors in device fabrication are also reviewed in order to minimize the detrimental impacts of the Schottky barrier for obtaining optimum device performance.</P>

Patterns of Plasma Bullet in Plasma Jets

Gook Hee Han,Je Huan Koo,Duk In Choi,Eun Ha Choi,Guangsup Cho Institute of Electrical and Electronics Engineers 2015 IEEE transactions on plasma science Vol. No.

<P>Composite charges applied to plasma striations were investigated through this paper. Bullets in plasma jets stemming from effective electrons made up of a moving target electron with screening electrons and ions around it were assessed using an atom-like structure induced by an external electric or magnetic field. To maintain a zero total charge, screening electrons and ions were assumed to be spherically and symmetrically distributed around a target moving electron -e, and the surrounding -e or +e was equivalent to the composition of an electric field vortex and an electron. Electrons moving around a spherical orbit were found to have positive charges under a strong electric field but negative charges under a weak field, mainly because the cross-sectional area of the flux was very small. In plasma jets, striations are a phenomenon that may occur when charges gather in the presence of an electric or gauge field. A plasma striation can occur if the effective charge exceeds a critical value determined by setting the derivative of the effective charge to zero, but only if the electric field lines passing through the striation are connected.</P>

Doping-Free Inverted Top-Emitting Organic Light-Emitting Diodes With High Power Efficiency and Near-Ideal Emission Characteristics

Changhun Yun,Hyunsu Cho,Tae-Wook Koh,Ji-Hoon Kim,Jeong Won Kim,Yongsup Park,Seunghyup Yoo Institute of Electrical and Electronics Engineers 2012 IEEE transactions on electron devices Vol.59 No.1

<P>Inverted top-emitting organic light-emitting diodes (ITOLEDs) with high power efficiency and near-ideal emission characteristics are demonstrated by using the combination of the following: 1) an electron-injection layer composed of Cs<SUB>2</SUB>CO<SUB>3</SUB>, which lowers the turn-on voltage; 2) an electron-transporting layer with optimal electron mobility, which enhances the electron current and thus improves the carrier balance; and 3) a dielectric/metal/dielectric multilayer electrode that works as a damage-free top transparent anode optimized to achieve high efficiency and ideal emission characteristics. By this approach, ITOLEDs with power efficiency values of 3.8 and 30 lm W<SUP>-1</SUP> are demonstrated in fluorescent and phosphorescent types, respectively, at a luminance value of 1000 cd m<SUP>-2</SUP> with little distortion in spectral/angular characteristics.</P>

Design of a 6-MW Solid-State Pulse Modulator Using Marx Generator for the Medical Linac

Lim, Heuijin,Jeong, Dong Hyeok,Lee, Manwoo,Ro, Sung Chae Institute of Electrical and Electronics Engineers 2017 IEEE transactions on plasma science Vol. No.

<P>The linear accelerators (linacs) producing high energy and high power of electron-beam or X-ray beam have been used in medicine, industry, national security, etc. In the linac, the electrons are generated by the electron gun and accelerated in the accelerating column with the high-power RF fields. The high-voltage pulses from the pulse modulator are supplied to the RF power source and the electron gun. The pulse modulator is one of the big and expensive components in the linac. The commercial medical linacs commonly use the pulse modulator based on the thyratron-switched pulse-forming network. In order to improve the power efficiency, achieve the system compactness, and optimize the cost and space, the solid-state pulse modulator based on the Marx generator was proposed. The low-power solid-state pulse modulator was developed for the electron gun operation. The conceptual design and functional results were confirmed. In order to apply it to the RF power source, such as a magnetron or a klystron, the 6-MW pulse modulator with the same Marx scheme is proposed. It consists of 40 storage-switch stages and one high-voltage pulse transformer, producing the pulse of 50 kV and 120 A required by the magnetron in the medical linac. A storage-switch stage was designed for insulated gate bipolar transistors to switch high current of 280 A and 720 V and to use the capacitor of 25 mu F which was chosen for the voltage droop of 10% with the pulsewidth of 5 mu s. The prototype system with eight storage-switch stages was fabricated and tested with a load system. The performance results show that it can be extended to be the 6-MW solid-state pulse modulator. In this paper, we describe the design features, and discuss the results and also the future plan to optimize the solid-state pulse modulator in the medical linac.</P>

A Low Power and Area Scalable High Voltage Switch Technique for Low Operation Voltage in MLC NAND Flash Memory

KANG, Myounggon,PARK, Ki-Tae,SONG, Youngsun,LEE, Sungsoo,SONG, Yunheub,LIM, Young-Ho The Institute of Electronics, Information and Comm 2010 IEICE transactions on electronics Vol.93 No.2

<P>A new low voltage operation of high voltage switching technique, which is capable of reducing leakage current by an order of three compared to conventional circuits, has been developed for sub-1.8V low voltage mobile NAND flash memory. In addition, by using the proposed high voltage switch, chip size scaling can be realized due to reduced a minimum required space between the N-wells of selected and unselected blocks for isolation. The proposed scheme is essential to achieve low power operation NAND Flash memory, especially for mobile electronics.</P>

Study on the Thermal Transient Response of TSV Considering the Effect of Electronic-Thermal Coupling

Li, Chunquan,Zou, Meng-Qiang,Shang, Yuling,Zhang, Ming The Institute of Electronics and Information Engin 2015 Journal of semiconductor technology and science Vol.15 No.3

The transmission performance of TSV considering the effect of electronic-thermal coupling is an new challenge in three dimension integrated circuit. This paper presents the thermal equivalent circuit (TEC) model of the TSV, and discussed the thermal equivalent parameters for TSV. Si layer is equivalent to transmission line according to its thermal characteristic. Thermal transient response (TTR) of TSV considering electronic-thermal coupling effects are proposed, iteration flow electronic-thermal coupling for TSV is analyzed. Furthermore, the influences of TTR are investigated with the non-coupling and considering coupling for TSV. Finally, the relationship among temperature, thickness of $SiO_2$, radius of via and frequency of excitation source are addressed, which are verified by the simulation.