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A new notion of control, resilient control, is discussed. It is not the same as the robust control where the controller guarantees control performance to the worst disturbance or resilient control system in the field of information technology. It has additional property to of recovery after a major disturbance and the ability for a discontinuous event. We utilize Monte Carlo Model Predictive Control, a kind of model predictive control that utilizes Monte Carlo simulation for optimization to establish such control. This paper discusses resilience in control with two applications; inverted pendulum on a cart with collision and recovery flight of a quadcopter.

As web-based open data sources become increasingly accessible and rich, translating and repurposing this data towards an educational goal is a topic of interest. Significant challenges exist in taking this data and translating it to a form meaningful, relevant, and engaging to the learner, addressing the gap between information, knowledge, and understanding. Games provide a key medium through which this may be achieved, though limited evidence exists as regards the best techniques, both pedagogical and technological, by which data can be translated to engaging and educational material. In this paper, we describe the approach adopted by a serious game supporting the development of healthy lifestyles amongst adolescents. The game itself places the player as a survivor in a post-apocalyptic scenario, tasked with survival and exploration. Utilising the United States Department of Agriculture's open data on nutritional information, four different mini-games are implemented in the form of two quiz-based approaches, a puzzle, and a system directly connected to wider game mechanics as a “crafting” system. We discuss the design rationale behind these games and their differences, and present the outcomes of usability testing showing some insight into the various techniques. Our discussion contributes to the theory of how common game mechanics might best be applied to open data to provide effective and engaging educational experiences.

Linear resonant actuators (LRAs) have been used in a wide range of applications [1] because they can reciprocate in a comparatively short stroke in spite of their compact size and light weight. However, the amplitude of LRAs severely decreases when external loads are applied. With applications such as electric shaver or air compressors, the amplitude of the mover needs to be able to be arbitrary controlled regardless of how the external load changes.

This paper proposes a maximum torque per ampere (MTPA) control method based on V/f control for the Interior Permanent Magnetic Synchronous Motor (IPMSM). The V/f control is inherently a position sensorless method. Therefore it is simpler than the conventional methods such as the sensorless vector control method. In addition, the MTPA control can be achieved by controlling the reactive power without the information of magnet pole position. The proposed MTPA control achieves high efficiency because the copper loss can be reduced. In this paper, the proposed method is demonstrated by the by the experiments. Then, the output current can be reduced by 76 % in compared to the V/f control without MTPA. The validity of the proposed method is confirmed by experimental results.

The purpose of this study is to develop a method to measure untransposed transmission line parameters for protection relay setting. For relaying schemes such as distance relays, current differential relays and fault locators, it is very useful to ascertain the precise setting values in service, without the need for setting calculations prior to installation, and also for the relays to be able to adaptively change their settings as the system configuration changes. This paper describes a method of live line measurement of the parameters of an untransposed three phase one circuit transmission line and untransposed two parallel transmission lines and necessary conditions to measure line parameters. We propose a mathematical approach using synchronous voltages and line currents at both ends of the line in different states, where two models, the equivalent PI circuit and distributed constant line, are employed. For two parallel transmission lines, applying a mode decomposition, we show that two parallel transmission lines can be transformed into double independent three phase circuits. The efficiency and issues are shown using several simulation examples in MATLAB.

Ground penetrating radar (GPR) ground wave was used at a natural Kanto loam (i.e. Andisol) site to examine the influence of seasonal variations on surface soil-moisture content. Kanto loam is a type of volcanic ash soil found widely distributed in Japan. In order to investigate the influence of surface soil conditions on GPR based estimates, the study site was divided in two zones: with and without vegetation. Measurements were conducted at regular intervals during a three month monitoring period. Results indicated that GW was sensitive to the surface soil conditions as well as to seasonal variations. A significant increase in moisture content was observed in the vegetated zone over that of the bare zone during a period of a day after precipitation (i.e. September 1st). It shows that in the vegetated zone moisture in plants themselves, including roots, stems, and leaves, affects GPR measurements, leading to higher moisture content than in the bare zone. However, the influence of vegetation was not found to have a large impact during periods of good weather. The effectiveness of surface soil conditions with seasonal variations on GPR-based moisture content provided a clear insight to agricultural management prospectivies. This research confirmed that Kanto loam can be a good GPR site for noninvasive mapping of moisture content regardless of the presence of organic matter, silt, and clay content.

A metallic waveguide is one of effective media for millimeter- and submillimeter-waves because of the advantage of low-loss. This paper describes trial fabrication of a PTFE-filled waveguide bandpass filter (BPF) with the use of the SR (synchrotron radiation) direct etching process of PTFE, sputter deposition of metal, and electroplating. PTFE is known as a difficult material to process at high precision. However, it has been reported that PTFE microstructures can be fabricated by the direct exposure to SR. In this paper, an iris-coupled waveguide BPF with 5-stage Chebyshev response is designed at Q-band, and the fabrication procedure for the PTFE-filled waveguide BPF is described. The measurement results of the fabricated BPF are shown.

The purpose of this study is to develop a method to measure transmission line parameters for protection relay setting. For relaying schemes such as distance relays, current differential relays and fault locators, it is very useful to ascertain the precise setting values in service, without the need for setting calculations prior to installation, and also for the relays to be able to adaptively change their settings as the system configuration changes. This paper describes a method of untransposed live line measurement of the parameters of a three phase transmission line. We propose a mathematical approach using synchronous voltages and line currents at both ends of the line in different states, where two models, the equivalent PI circuit and distributed constant circuit, are employed. The efficiency and issues are shown using several simulation examples in MATLAB.

For the strain (change in thickness) estimation method that we had been using, we have to estimate the displacements of many target points. When we use a correlation based method to estimate the displacements in the human body, accurate strain estimation is difficult. One of the reasons is the change in the center frequency and the amplitude of the RF echo due to the frequency dependent attenuation and the interference of reflected waves from scattering sources in the living body. In this paper, we propose a new strain estimation method that has advantage over the previous method and check the validity of the new method experimentally using an artery-mimicking phantom.

For 50-ohm microstrip and coplanar lines constructed on a copper-clad ceramic/PTFE glass cloth laminate substrate AR-1000, the propagation constants gamma=alpha+jszlig, where alpha is attenuation constant and beta is phase constant, are calculated with the 3-dimensional electromagnetic simulator HFSS and 2.5-dimensional simulator Sonnet em in the frequency range 1 to 20 GHz. Particularly, the attenuation constant due to the conductor loss alphac and one due to the dielectric loss alphad are evaluated separately from calculations. The results calculated for accurate measured values of relative permittivity in the normal and tangential directions for the AR1000 substrate and of surface and interface resistances of copper foils plated on the both sides, are compared with ones for the nominal values presented by a manufacturer.

Small sized surface acoustic wave (SAW) duplexer for wide band code division multiple access (W- CDMA) system with a good temperature coefficient of frequency (TCF) and good frequency characteristics has been required. However, the size of conventional SAW duplexer for W-CDMA using Al-electrode/50-70degYX- LiNbO3 is large (3.8x3.8 mm2) and its TCF is not good (-80ppm/degC). So, this duplexer can't satisfy its severe specifications in the all temperature range from -30 to 85degC. When SiO2 film is deposited on this substrate to improve the TCF, the frequency characteristics is deteriorated by convex portions on the SiO2 surface caused by SiO2 sputtering. This time, by applying a flip chip bonding process, a fiattened-SiO2/Cu- electrode/substrate structure, and a YX-LiNbO3 substrate, a small sized (3x2.5x1.2 mm3) SAW duplexer having good characteristics (such as low insertion loss and large attenuation) and good TCF has been realized for the first time. Here, the SiO2 film is used to improve the TCF, the flattened-SiO2 to obtain high Q, the thick Cu- electrode to obtain the large reflection coefficient, and the YX-LiNbO3 substrate to obtain the large coupling factor and not to generate Rayleigh wave which causes spurious at the SiO2 of 0.3lambda and the Cu-electrode of 0.05lambda.

To investigate human brain activities in association with emotional speech, we developed a novel voice analysis system connected to a functional magnetic resonance imaging (fMRI) machine. Participants spoke inside the MR magnet during which BOLD activities of the brain was measured. Speech voice was transmitted through the newly developed mask-microphone inside the magnet to the external computer and was processed by the emotional voice analysis system. Two participants conversed without hindrance and their emotional state was analyzed. Using the system, we were able to detect brain activities during speech and simultaneously evaluate the human emotional voice.

Mobile/wireless services have been developed using Java technology on Java-enabled, battery-powered handheld devices. These services such as games, web browser, audio/video players, are easily accessible, but consume a huge amount of power. The handheld devices typically last for 5 to 6 hours in running the Java applications. A new technique for low power consumption is to be developed. Using runtime power control in Java-enabled, battery-powered handheld devices. The technique improves in-memory compression to minimize memory consumption and a memory bank partitioning technique to cluster memory banks into active banks and inactive banks are powered off dynamically. The runtime power control is integrated into a Java runtime environment (JREPC) using a hardware/software codesign technique. The JREPC is studied and examined with benchmark applications (web, email, audio/video, game, M- commerce). The in-memory compression reduces more than 50 % of memory consumption. Only half of the memory may be activated. The time overhead due to the in-memory compression is negligible using a hardware de/compressor. We believe that the in-memory compression with the memory bank partitioning technique is a key to achieving low power consumption in the Java-enabled, battery-powered handheld devices.

A miniaturized x-ray tube specialized for in-situ geological and petrological x-ray analyses of rocks and powder samples on the lunar surface is being developed. Our primary motivation for the miniaturized x-ray tube is to mount on spacecraft for a future Japanese lunar lander/rover mission [1], which is the next Japanese lunar exploration program to the SELENE lunar orbiter, and perform remote controlled x-ray generators for in-situ geological x-ray analyses of lunar surface soil samples. Possible x-ray instruments for the mission would be: the x-ray fluorescence and diffraction analyzer on the lander [2], the x- ray fluorescence spectrometer mounted on the arm of the rover and in the "mole unit" for the investigations of underground. All above instruments requires a miniaturized x- ray tube fulfilling enough lightweight and downsized volume, low power consumption, and stable performance under the space operations while mission term.

We developed 8 times 8 beam-deflecting optical switch with a switching speed within one microsecond utilizing electro-optic effect of PLZT. A newly-developed radial optical path design and putting-in packaging structure with a monolithic PLC platform were applied.

Only summary form given.Java has been introduced to the mobile/wireless handsets and Java enabled handsets are now prevalent in the market, showing their successful launch. A variety of attractive services have been developed and promise a lot of fun to our daily lives, which are however targeted to the high end products that are very expensive. We focus on economic types with similar performance to the high end products. Memory compression is a key technique to achieve the goal and is integrated into a Java runtime environment. We save memory with runtime compression and reduce power by a memory bank partitioning technique (powering off unused memory banks). In memory compression algorithms and the Java runtime environment are studied. The Wilson and Kaplan (WK) algorithm is discussed as in-memory compression and introduced to the Java heap as an alternative of the garbage collection (gc). Experiments show around 10% of speedup and up to 45% of memory saving in the application core part (20.0 % of memory overhead for a user interface). The Java system using the memory compression outperforms its base configuration and will give further chance to reduce memory demand in combination with the garbage collection designed for the Java compressed heap. Experiments show that the in-heap memory compression technique can save more than 50 % (up to 60 %) of the heap demand and that half of the memory banks for the Java heap may never be turned on. 50 % of the power consumption (memory leakage current) can be saved. The hardware compressor and decompressor are currently ten thousand times faster than the software counterparts. The time overhead could be negligible by introducing the hardware compressor and decompressor. Hardware/software codesign is an additional key to achieve our goal. The contribution of the runtime memory and heap compression is threefold: small memory demand, lower power consumption, and negligible time overhead in battery-powered handsets. Future work includes several issues unsolved in the Java memory compression: studies of integration of CLDC Hot Spot implementation and extension of the Java virtual machine to the traditional virtual machine.

Recently, a number of Web sites offer guidance through facilities using omnidirectional images with omnidirectional cameras that can take 360-degree images. As a result, Internet users can survey the surroundings from an arbitrary viewing direction by mouse operations. However, an image space constructed with only one omnidirectional image has two problems. One problem is a limitation in the elevation of the viewing area that can be seen. The other problem is that we cannot change our aspect from that of the image. The present paper describes a method of integrating a lower and an upper hemisphere omnidirectional image as one space in order to improve the elevation limitation and the construction of a virtual walkthrough image space by interpolating between two adjoining image spaces to enable the aspect to be changed.

Human movement such as walking or traveling in a wheelchair involves vertical movement. Previously, we developed a real ubiquitous round-the-clock 3D navigation system for pedestrian point-to-point navigation, in which position detection is driven mainly by dead reckoning with the help of RFID technology. A number of navigation systems have been developed for pedestrians, but few consider dynamic information. The newly proposed "Moudo-Cane" system extends the previously developed system [1] and provides more reliable and convenient guidance throughout the journey, even when GPS information is unavailable, in an attempt to not only provide a universally available navigation system, but also to provide assistance for visually impaired or wheelchair-bound users by taking their preferences into account.

A large percentage of traffic accidents are caused by driver negligence or inattentiveness. If negligence or inattentiveness can be detected before an accident occurs, the number of accidents may be decreased. The pupil diameter of a person changes under various conditions. For instance, the pupil diameter of a person who is thinking becomes large, and in contrast, the pupil diameter of a tired person becomes small. These effects have been proven through a number of psychology experiments [1, 2]. The pupil diameter, along with data concerning the blink duration and the change in eye direction are gathered by the proposed system. The system detects the attention level of a person based on the pupil diameter. The recognition rate of a person's attention level has been improved using these ancillary data regarding the blink duration and the change in eye direction. In the present study, we describe a newly developed robust pupil diameter measurement system that minimizes the influence of certain circumstances and warns the driver when it judges the driver to be more prone to accidents.

The inversion channel IEMOSFET has been fabricated on the 4H-SiC carbon-face substrate. The channel resistance was successfully reduced to 1 mOmegacm2 due to the high inversion channel mobility on the carbon-face epitaxial layer. The extremely low specific on-resistance of 2.7 mOmegacm2 was achieved with the blocking voltage of 700V. This specific on-resistance is the lowest in the normally-off MOSFET with the blocking voltage higher than 600 V

This paper studies audio-video transmission in a wireless LAN with the EDCA of the IEEE 802.11e MAC protocol in terms of application-level QoS and user-level QoS (i.e., perceptual QoS). By simulation, we first compare the performance of the EDCA and the legacy IEEE 802.11 DCF in the case where audio, video, and data are transmitted in a common wireless channel. The EDCA supports priority control for multimedia transmission. Numerical results show that the EDCA can improve the audio and video quality of the DCF when data traffic load is heavy. We then study the effects of dynamic video-resolution and media synchronization control on the application-level QoS. Simulation results show that the two kinds of control at the application layer in addition to priority control with the EDCA at the MAC layer is effective in achieving excellent application-level QoS of audio-video transmission. Furthermore, we assess user-level QoS by the method of successive categories, which is one of the psychometric methods

Applying a small size cooling system is essential to avoid thermal noise in the field of micro-electronics. Fine thermoelectric materials are required to construct the system. A glass sealed melt spinning process was attempted to fabricate the fine materials. Bi2Te 3 wires of 75 mum in diameter with oval cross section were successfully obtained. The original electrical resistivity and Seebeck coefficient of the wires were maintained after the process

The capillary pumped loop has been widely investigated for a space thermal control device. This cooling device with high reliability and thermal controllability is considered to be suited to cool the electronic device like a tower-type personal computer, because the capillary pumped loop is good for absorbing heat from high heat flux region like a CPU, transporting it and releasing it from the large surface area like a packaging of the tower-type computer. In this study the capillary pumped loop was manufactured as a cooling device for the tower-type personal computer, and the heat transport characteristics was investigated. The experimental equipment consisted of the evaporator, the condenser, the liquid path and the vapor path. The heat transport length was set to 2500mm considering the air-cooled heat release area of the condenser. In the 1st report the effect of the wick dimension, cooling water temperature, evaporator height above the condenser were investigated. In this study, the influence of the inclination of the evaporator on the heat transport characteristics was mainly investigated. In results, this capillary pumped loop was able to work within the inclined angle of 20deg, but the maximum heat transport rate decreased as the inclination increased

This paper investigates the detailed effects on language learners of various communication tools meant to improve course coordination. Activities with video conferencing, chat, and BBS were introduced as 3-week language exchange sessions in one semester. Students exchanged information and opinions on Japanese culture with students learning the Japanese language at a research-based university in Melbourne, Australia. Students in Japan used English, while students in Australia used Japanese and some English. After these online sessions, we conducted a survey using a questionnaire to collect the responses of the students in Japan on their motivation, attitudes and tension in video conferencing, chat, BBS sessions. In addition to the above activities, a face-to-face discussion with overseas students was conducted. As a result of the analyses, we found that there are 2 important factors that affect student's learning processes in each communication tool. Video conferencing has conflicting effects, that is, it has an advantage of increasing motivation to communicate more, but in contrast, it has a disadvantage of making students feel nervous and embarrassed. Possible reasons behind the feeling of nervousness and embarrassment might be not only their making mistakes in grammar or pronunciation but also their personalities and characters. On the other hand, the effect of chat is to provide stimulus to develop vocabulary and to enhance their cultural awareness, and the effect of BBS is to provide relaxed feelings in online communication and to increase students' desire to develop vocabulary.

The works for representing human skills are attracted, which human experts have cultivated in long experiences. Recently, there are many literatures with respect to skill-based controllers which human skills are represented by artificial neural networks. The technique for representing the human skills plays an important role in various industries, for example, manufacturing systems and process systems. In this paper, a skill-based PID control scheme is proposed, which extracts skills of human experts as PID gains. This controller is designed by using three-layered artificial neural networks. The effectiveness of the proposed skill-based PID control scheme is investigated through an application for a pressure control system. Furthermore, the characteristic of the PID controller constructed based on the human skills is interpreted in the frequency domain

Walking is the most fundamental means of human transportation. Unlike travel by car, walking is not planar, but rather stereoscopic. We therefore developed a real navigation system for pedestrian point-to-point navigation. We propose herein a method of 3D pedestrian navigation, in which position detection is driven mainly by dead reckoning. The proposed method enables ubiquitous round-the-clock 3D positioning, even inside buildings or between tall buildings. In addition, pedestrian navigation is customized by changing the costs of the road network links. Finally, a positioning data accumulation system is implemented so that we can log tracks and easily incorporate new roads or attributes in the future.

A degradation mode by FN stress is investigated comprehensively. We demonstrate that this degradation really occurs in driver MOSFETs in actual circuits after E/W operation. We also exhibit that this degradation has strong correlation with total injected gate and substrate current and propose a hot-hole induced degradation mechanism.

A robust low-k diffusion barrier, i.e., advanced SiC(O) (A-SiC(O), k = 3.5), was developed to attain a keff of less than 2.7 for reliable ultra-low-k/Cu integration for 45-nm node technology and beyond. A new precursor that requires that requires no oxidizing agent was introduced for deposition to obtain higher film density while maintaining the k-value. The A-SiC(O) film has a low leakage current because of its low defect density and a comparable barrier property with conventional SiC. Drastic improvement in the keff and TDDB lifetime were obtained by adopting A-SiC(O) without using underlying SiCN and oxidizing agent in the deposition, Reliable ultra-low-k/Cu integration was accomplished by combining A-SiC(O) and Aurora-ELK (k=2.3), which has a high modulus of 7.2 GPa, with a UV cure

The power MOSFET on 4H-SiC is an attractive high-speed and low-dissipation power switching device. The problem to be solved before realizing the 4H-SiC power MOSFET with low on-resistance is low channel mobility at the SiO2/SiC interface. This work has succeeded in increasing the channel mobility in the buried channel IEMOSFET on carbon-face substrate, and has achieved an extremely low on-resistance of 1.8 mΩcm2 with a blocking voltage of 660 V.

We report a high-stable and high-beam-quality 589.158 nm radiation in sum-frequency generation using LD-side-pumped Nd:YAG laser oscillators. Average ouput power reached 4.6 W and it was stable within plusmn2.2% for 8 hours.

To reduce the effective k-value to less than 2.7 for the 45-nm node, direct CMP of a porous SiOC film (k = 2.3-2.6) without a protective cap layer was applied to Cu damascene fabrication by using a damage-less sacrificial film process. The key is controlling the molecular size of surfactants in the CMP slurries or cleaning chemicals, which are related to the moisture uptake and watermark generation of hydrophobic porous SiOC films. We found that the selectivity of CoWP deposition improved on a hydrophobic SiOC surface

Java technology has been integrated into mobile/wireless computing because of its rich support to portability (cross-platform nature), reusability (development libraries), and short-time development. Given a small handset, we are now able to access almost all types of services on Internet: mobile commerce, telephony, email, Web service, global position systems, and MP3 music. We, however, still suffer from its small memory limitation and power-hungry feature. We introduce a hardware compression technique to Java-enabled mobile/wireless devices and provide small memory demand. Experiment results show 25% to 50% memory saving.

An ultra violet (UV) cure was investigated to improve the mechanical and electrical properties of porous carbon-doped PECVD (plasma enhanced chemical vapor deposition) oxide film (k

efinition Still Picture Filing System using image cornpression technology is describ e configuration of the system,the structure of the s picture process or, and applications are described briefly. It is concluded at the quality of the reproduced picture image is quite satisfactory when it is used as a presentation aid.

New apparatus to measure the head and eye movements in real time has been developed. System is used as an instrument to diagnose vertigo patients. Eye movement is observed by a charge coupled device (CCD) image sensor camera. Motion of head is detected by 3SPACE ISOTRAK, of which working principle is measuring orthogonal magnetic fields. Data of three normal and three abnormal subjects including vertiginous persons have been acquired by the system.

New Electron-Beam Direct-Writing (EB-DW) technology using a conductive bottom layer resist, toluene soaking, and a new proximity-effect correction method is applied to high-density O.8pm CMOS ASICs and a WSI neurocomputer consisting of three metal layers. Pattern data processing is also improved. Experiments show good results for gate arrays and completely-functional WSI neurocomputers.

We investigate the content of pteridine levels in mouse liver under exposure to a 50 Hz linearly (vertically) polarized magnetic field. Tetrahydrobiopterin (BR/sub 4/), neopterin (NP), biopterin (BP) and GTP-CHI activity were measured. Five week-old mice were exposed continuously to 50 Hz, 0.35 mT (RMS) for periods of 1, 3 and 6 weeks. The level of BH/sub 4/ in the exposed group was no different from that of the sham-exposed group. The levels of NP in both groups became almost the same. Due to no changes in NP and BH/sub 4/ level, it is suggested that the vertically polarized magnetic field does not affect the immune system and biosynthetic pathway from q-BH/sub 2/ to BH/sub 4/ in mice. There were no changes in the level of BP between the two groups. From these results, the vertically polarized magnetic field does not affect the pteridine level in mice.

The composition dependence near the morphotropic phase boundary (MPB) composition of refractive index and electric-optic (EO) coefficient of the epitaxial (Pb/sub 1-x/, La/sub x/)(Zr/sub 1-y/, Ti/sub y/)/sub 1-x/4/O/sub 3/ [PLZT] thin films were investigated. PLZT films were fabricated on Nb doped SrTiO/sub 3/ [Nb-STO] (100) substrates by a sol-gel method. The TE- and TM-mode of optical properties were measured separately. Depending on La content the refractive index were varied up to 2 %. This is adequate for fabrications of waveguide structures. Birefringence became small from 4/spl times/10/sup -3/ to 1/spl times/10/sup -3/ as the crystal structure became close to cubic. The EO coefficient of PLZT (9/65/35) thin films was 45 pm/V, and only a small polarization dependence of the EO coefficient was observed. PLZT optical waveguide that was structured changing PLZT compositions was fabricated on Nb-STO substrate. TE- and TM-modes have similar EO coefficients of 41-42 pm/V.

In daily life, we sometimes find it hard to communicate with people from cultures not our own. In the field of Computer Science (CS), however, we have been able to discuss our research with pictures and program source code. As opportunities of attending and presenting papers at international conference are increased, we found that many recent hot topics belong to multiple fields, including those considered to be outside the traditional computer science field, such as biology, business, etc. This research trend requires us to have a technique of quickly acquiring subject matter knowledge of fields that are unfamiliar to us, and to discover a strategy for clearly explaining our key idea to non-experts. This technique and strategy will promise smooth cooperation with experts in other fields and will be a key issue for our successful research across current and new areas of studies. We present a list of obstacles that CS students face when trying to communicate along these new frontiers, and we discuss a strategy for professional communication through classroom presentation.

M-commerce has shown up as e-commerce in mobile and wireless communication, and now deals with on-line banking, stock trading, auctions, transactions, and mobile media. M-commerce applications are implemented with, for example, Java technology that supports a client-and-server model and cross-platform mobile applications. They are attractive, but, need a large heap space, which may slow down the execution, lead to poor interactive response, and sometimes cause "out of memory" failure. We propose a Java computation mechanism with heap de/compression modules that reduce memory demand and allow client applications and embedded devices to take the advantage of compression techniques. Results show the impact in space and time efficiency of the proposed mechanism. The space efficiency is 1.80 to 2.50 and the speed is competitive with that of original Java technology. We believe that the proposed mechanism provides a good runtime environment for mobile/wireless computing.

4 W coherent yellow light generation at 589 nm was achieved by sum frequency generation of two mode-locked lasers generating at 1064 nm and 1319 nm for laser guide star of the astronomical telescope.

65% optical-to-optical conversion efficiency was achieved in second harmonic generation of a Nd:YAG laser using 9-ppm cerium-doped KTP. Optical damage was fully suppressed and output power was maintained with heating at 145 degrees Celcius.

An electron optical instrument for evaluation of emission characteristics of multi emitters is developed to perform the following functions: (1) observation and recording of dynamical behaviors of emission patterns from the whole multi emitter unit as well as each individual working emitter; (2) image observation of geometrical shapes of individual emitters and gates; (3) measurement of emission current stability from the whole multi emitter unit as well as each individual working emitter. A field emitter array type of multi emitter is used as a specimen. The instrument is found to have the capability of real time and simultaneous observation of LEEM and FEEM images as well as PEEM and FEEM images.

A 780 nm multi-mode VCSEL, to meet the requirements for a new GI plastic optical fiber, are reported. It has 4 spots driven simultaneously like a single spot and hence the optical power needed from each spot is reduced to 1/4. As a result, the MTTF obtained is well over 200,000 hr at 60/spl deg/C under 3 mW operation, with a narrow beam divergence angle of less than 18/spl deg/ (1/e/sup 2/). This VCSEL also shows wide-open 5 Gbps eye diagrams at standard driving conditions, which is sufficient for most home network applications. Applications using this VCSEL and Lumistar, such as optical DVI (digital visual interface) and GBIC (Gigabit interface connector) modules are shown too. Furthermore, a 780 nm VCSEL array with independently addressable 32 spots, for laser beam printer applications, is reported. Each spot has a single-mode optical power of more than 1.2 mW at 60/spl deg/C and their uniformity is within /spl plusmn/1%. A high resolution of 2400 DPI and a print speed of 12.5 ppm, in color, was achieved by incorporating this array as an optical source.

For measurement of minute change in thickness using ultrasound, the phase tracking method based on the constraint least-squares approach has been developed. By using the thickness change of arterial wall measured by this method, local elastic characteristic of the arterial wall is calculated, and fast calculation makes a real-time 2D measurement of the elastic characteristics possible. We have developed a real-time measurement system that displays the 2D image of the elastic characteristics of the arterial wall. In order to assess the measurement accuracy of the system, we made a phantom of silicone tube, and the thickness change of the tube wall was measured by the system and another off-line ultrasound measurement system. From the experimental results, it was obtained that our novel system had an accuracy of about 0.2 /spl mu/m. using this system, we measured the thickness change of carotid arterial wall, and obtained real-time 2D images of the elastic characteristics.

This paper assesses the media synchronization quality of audio-video transmission over the IEEE 802.11b wireless LAN under Bluetooth interference by experiment. In this situation, the temporal constraints of audio and video may be disturbed, since the Bluetooth interference cause delay jitter due to retransmission and carrier sensing in the MAC layer of IEEE 802.11b. In the experiment, a media server transfers stored video and audio streams to a mobile terminal over an IEEE 802.11b wireless LAN; as radio interference from Bluetooth, two other terminals transmit data over Bluetooth at the same time. We examine the influence of Bluetooth on the audio-video transmission over IEEE 802.11b in terms of the Bluetooth signal level and its data load. We also apply a media synchronization control scheme and confirm its effectiveness.

This paper proposes an example of an open architecture for a robot controller. This architecture is a multi-agent system with blackboard files. The key interfaces between the agents are the task knowledge database and motion table, which are described by character code.