| A Three-Dimensional Finite Difference Time Domain - Perfectly Matched Layer Algorithm for Nonlinear Dispersive Media |
10 MAR 2000 |
38 pages |
| Authors:
S. J. Yakura; AIR FORCE RESEARCH LAB KIRTLAND AFB NMDIRECTED ENERGY DIRECTORATE
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 | Starting with unsplit-field uniaxial perfectly matched layer (PML) formulation, a second-order accurate finite difference time domain. Perfectly matched layer (FDTD-PML) algorithm is obtained for the first time using the piecewise-linear approximation for nonlinear dispersive PML media. In the absence of the PML interface, the nonlinear dispersive FDTD-PML algorithm reduces to the usual nonlinear dispersive FDTD algorithm. |
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| A Three-Dimensional Finite Difference Time Domain - Perfectly Matched Layer Algorithm Based on Piecewise-Linear Approximation for Linear Dispersive Media |
24 FEB 2000 |
22 pages |
| Authors:
S. J. Yakura; David Dietz; AIR FORCE RESEARCH LAB KIRTLAND AFB NMDIRECTED ENERGY DIRECTORATE
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| Starting with the unsplit-field uniaxial Perfectly Matched Layer (PML) formulation, a second-order accurate Finite Difference Time Domain (FDTD) - PML algorithm is obtained using the piecewise-linear approximation. Use of the FDTD-PML algorithm results in the proper long time limit behavior where the electric field value decreases exponentially to zero inside a PML medium long after an electromagnetic pulse is incident on the PML medium. The behavior ... |
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| A Stability Analysis of the Perfectly Matched Layer Method |
12 NOV 1999 |
16 pages |
| Authors:
S. J. Yakura; David Dietz; Andy Greenwood; Ernest Baca; AIR FORCE RESEARCH LAB KIRTLAND AFB NMDIRECTED ENERGY DIRECTORATE
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| We perform a detailed stability analysis based on the unsplit-field uniaxial perfectly matched layer (PML) formulation. Our finding shows that it is essential to have transverse field gradients present at all times to stabilize PML calculations. In the absence of transverse field gradients, the PML method becomes unstable with the axial field components growing linearly in time. |
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| Penetration of Microwaves Through Dispersive Concrete Using a Three- Dimensional Finite-Difference Time-Domain Code |
30 JUN 1999 |
27 pages |
| Authors:
S. J. Yakura; David Dietz; AIR FORCE RESEARCH LAB KIRTLAND AFB NMDIRECTED ENERGY DIRECTORATE
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| In this paper, we present a new formulation of a three-dimensional Finite-Difference Time-Domain (FDTD) algorithm that is applicable for studying the penetration of microwave pulses in conductive and dispersive materials, such as concrete. We investigate the effects of microwaves penetrating into conductive and dispersive concrete using the newly formulated algorithm incorporated into a three-dimensional FDTD code. Because of the dispersive properties of concrete, both conductivity and polarization terms are taken ... |
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| Finite-Difference Time-Domain Calculations Based on Recursive Convolution Approach for Propagation of Electromagnetic Waves in Nonlinear Dispersive Media |
30 OCT 97 |
30 pages |
| Authors:
S. J. Yakura; Jeff MacGillivray; AIR FORCE RESEARCH LAB KIRTLAND AFB NMDIRECTED ENERGY DIRECTORATE
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| The piecewise linear recursive convolution (PLRC) approach has been shown to provide much improved accuracy over the usual discrete recursive convolution approach while retaining the efficient use of computer memory storage and fast computational speed for finite-difference time-domain (FDTD) electromagnetic propagation calculations for linear dispersive materials. In this paper, an idea behind the implementation of the PLRC approach is extended to handle nonlinear dispersive media, specifically for the convolution integral ... |
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| Visit of the Korea Advanced Institute Science and Technology (KAIST) |
19 SEP 94 |
4 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| South Korea's Korea Advanced Institute of Science and Technology (KAIST) was visited on 28 June 94. The intent of the visit was to learn about basic and advanced research activities carried out at KAIST and make initial contacts with KAIST personnel for any future international collaborative research programs which are of mutual interest to both the US Air Force and KAIST. KAIST is Korea's premier technical institute for providing both ... |
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| Visit of South Korea's Electronics Telecommunications Research Institute (ETRI) |
30 JUN 94 |
7 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| South Korea's Electronics Telecommunications Research Institute (ETRI) was visited on 30 June 94. The intent of the visit was to learn about basic and advanced research carried out in electronics and telecommunication fields at ETRI and also to establish initial contacts with ETRI personnel for any future interactions in setting up collaborative research programs which can benefit both the US Air Force and ETRL, |
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| Visit of the Korean Aerospace Research Institute (KARl) |
29 JUN 94 |
5 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| To learn about newly established Korean research institutes working specifically on aerospace research, Dr Tom Davis and I visited the Korean Aerospace Research Institute (KARl), located in Daeduck Science Town, Taejon, for an hour between 1400 and 1500 on the 29th of June, 94. The visit was arranged by Mr F. Kenneth Crosher, science counselor of the US Embassy in Korea, before we departed Japan. The purpose of the visit ... |
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| The Photomask Japan '94 Held in Kawasaki Science Park, Kanagawa, Japan on 22 April 1994 |
22 APR 94 |
6 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The Photomask Japan 94 symposium, the first photomask meeting in the Far East, was held 22 Apr 94 in Kanagawa, Japan. In this one day meeting, 54 papers were presented covering such topics as mask fabrication, phase shift mask, x-ray and electron-beam masks, and metrology and equipment. In this report, selected papers on the development of sub 0.5 micrometer size masks are discussed. (AN) |
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| The International Conference on Thin Film Physics and Applications (2nd) Held in Shanghai, China on 15-17 April 1994 |
17 APR 94 |
6 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The Second International Conference on Thin Film Physics and Applications was held 15-17 April 94 at the Jin Sha Hotel in Shanghai, China. The level of Chinese research carried out in thin film technology was found to be still immature as compared with the U S., Japan, and Europe. Selected conference papers, presented by Chinese scientists, are included in this report to show the extent of research being carried in ... |
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| The Japan Society of Applied Physics Spring Meeting (41st) Held at Meiji University in Kawasaki, Japan on March 28-31, 1994 |
31 MAR 94 |
8 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The 41st Japan Society of Applied Physics Spring Meeting attracted a thousands of Japanese scientists and a few non-Japanese scientists coming mostly from Japanese universities, Japanese industrial research laboratories, and Japanese federally funded research centers. During a four day meeting, there were more than fifty simultaneous sessions in progress, covering most of the applied physics disciplines such as radiation and plasmas, measurements, optics, quantum electronics, optoelectronics, thin film physics, beam ... |
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| The IEEE Workshop on Micro-Electro-Mechanical Systems Held in Oiso, Japan on 25-28 January 1994 |
28 JAN 94 |
7 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The 7th International Workshop on Micro-Electro-Mechanical Systems, sponsored by the IEEE Robotics and Automation Society, was held 25-29 January 94 in Oiso, Japan. During this 3 day workshop, there were a total of 63 papers presented, consisting of 38 oral and 25 poster papers. Topics covered in this workshop were fabrication, sensor, actuator, device/system, and micro-robotics technologies of millimeter to micrometer-size electromechanical devices. One interesting paper presented in this workshop ... |
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| Visit to the Minister of International Trade and Industries' (MITI's) Electrotechnical Laboratory (ETL) on 25 October 1993 |
25 OCT 93 |
4 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| This trip report discusses high power laser research being carried out at Optoelectronics Division of the Minister of International Trade and Industry 's (MITI's) Electrotechnical Laboratory (ETL) for the generation of coherent soft x-ray radiation based on interactions of in tense ultrashort-pulse lasers with rare gases. Over the past few years, ETL researchers have performed experiments to find out mechanisms associated with interactions of ultrashort- pulse lasers with rare gases. ... |
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| The Micro-Optics Conference (4th) and the Topical Meeting on Gradient- Index Optical Systems (MOC/GRIN'93) (11th) Held in Kawasaki, Japan on 20-22 October 1993 |
22 OCT 93 |
5 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| This report discusses the technical papers presented at the joint meeting of the Fourth Micro-Optics Conference and the Eleventh Topical Meeting on Gradient-Index Optical Systems (MOC/GRJN'93), held 20-22 Oct 93 at Kawasaki, Japan. (AN) |
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| Trip Report - The 1993 Institute of Electronics, Information and Communication Engineers (lEICE) Fall Conference |
14 OCT 93 |
4 pages |
| Authors:
S. J. Yakura; AIR FORCE OFFICE OF SCIENTIFIC RESEARCH BOLLING AFB DC
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| The 1993 Institute of Electronics, Information and Communication Engineers (JEICE) fall conference was held 5-8 Sep 93 at Hokkaido Institute of Technology. There were 2,161 oral papers and panel discussion sessions in this domestic Japanese conference. Conforming to the usual pattern of the domestic Japanese conference, there were no poster papers. One noticeable paper addressed in this conference was the generation of a 2.5 picosecond soliton pulse at 15 GHz ... |
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| A Tour of Japanese Research and Industrial High Power Laser Facilities |
29 JUL 93 |
5 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The following Japanese high power laser facilities were visited between 26-29 Jul 93: the Institute of physical and Chemical Research (RIKSN) in Wako, TRDI's 2nd Research Center in Tokyo, Mitsubishi Heavy Industries (MHT) in Takasago, Kawasaki Heavy Industries (KHI) in Kobe, and the Applied Laser Engineering Center (ALEC) in Nagaoka. At RiKEN, Dr. Katsumi Midorikawa has been actively pusuing research on high power lasers for more than 10 years. His ... |
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| International Conference on Optical Amplifiers and their Applications Held at Yokohama, Japan on 4-6 July 1993 |
06 JUL 93 |
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| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| SPring-8 at Harima Science Garden, Hyogo |
23 JUN 93 |
3 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The SPring-8 project site was visited on 23 Jun. 93. The SPring-8 project is one of the major projects managed by the Science and Technology Agency of the Japanese Government for construction of a world-class high energy synchrotron radiation facility (8 Gev). It started in the beginning of the 1989 Japanese Fiscal Year (Apr. 89). Since the inception of the project, 35% of the total estimated budget of $1.1 billion ... |
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| Eye Safe Laser Joint Working Group |
21 JUN 93 |
4 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The U.S.-Japan eyesafe laser working group meeting was held on 15-16, 21 Jun. 93 at the Japan Defense Agency's Technical Research Defense Institute (TRDI). The group discussed the framework for a U.S.-Japan eyesafe laser collaborative research project under the scheme of the Science and Technology Forum. Also discussed was the coordination effort between the U.S. Army Communications-Electronics (CE) Command (Mr. Wayne Grant) and the TRDI 2nd Research Center (Dr. Hideaki ... |
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| High Temperature Electronics Assessment |
07 JUN 93 |
6 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| As part of the AFOSR initiative, the High Temperature Electronics Assessment group has successfully completed the evaluation of high temperature electronics (HTE) technology in Japan. The group consists of Prof. Robert Davis of North Carolina State University, Prof. Hadis Morkoc of the University of Illinois, Mr. Kenichiro Nakano of Wright Laboratory, and Dr. S. Joe Yakura of AQARD. Between 25 May and 2 June 93, the assessment group visited Kyoto ... |
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| KEK, The National Lab for High Energy Physic in Tsukuba, Ibaraki |
11 MAY 93 |
4 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The National Laboratory for High Energy Physics, sometimes referred to as KEK, was established in April 1971 to conduct experiments in elementary particle physics. Research efforts are divided into four major areas: Accelerator Department, Physics Department, Radiation Safety Control Center, and Photon Factory. Under the direction of Prof. Shigenori Hiramatsu, Dr. David Whittum is carrying out research on designs of compact high energy accelerators that can achieve a steep potential ... |
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| Mitsubishi Electric Corporation Central Research Laboratory in Amagasaki, Hyogo |
26 APR 93 |
3 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The Mitsubishi Electric Corporation Central Research Laboratory is involved in the development of optical neuro devices for pattern recognition. The basic idea of the optical neuro device is to perform a vector multiplication in parallel. It uses the neural network concept to acquire the knowledge (in this case the desired pattern) from the real world through learning. It uses an array of GaAs photodetectors. They are exploring a novel concept. ... |
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| National Institute for Fusion Science in Nagoya |
09 APR 93 |
3 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The National Institute for Fusion Science, operated by the Ministry of Education, Science, and Culture (Monbusho) inside the Nagoya University campus, was visited. The current major research activity is focused on a new fusion reactor design concept called Heliotron. The research goal is to build a bigger Heliotron device and achieve DT reactions by the end of 1997. Currently, hydrogen plasmas are used in the existing small Heliotron device to ... |
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| NEC Central Research Laboratory in Kawasaki |
06 APR 93 |
3 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| The NEC Central Research Laboratory is located in Kawasaki, Japan. There are more than 1,200 personnel working at this site, focusing their research efforts in optoelectronics. The amount of defense related work done at NEC is less than 2%. NEC is active in the overseas technology exchange program. Currently, there are more than 30 foreign scientists working at various NEC laboratories. |
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| The New Sunshine Program, Japanese Long Term R&D Program For Solving Energy and Environmental Issues |
15 MAR 93 |
3 pages |
| Authors:
S. J. Yakura; ASIAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT APO AP 96337-0007
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| A summary of a new energy and environmental program called the New Sunshine Program is provided. The Minister of International Trade and Industry (MITI) of the Japanese Government established new guidelines in Mar 93 for dealing with energy and environmental issues for the next 27 years. The new guidelines are spelled out in the New Sunshine Program. |
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