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In this article, mechanical reliability of solder joints fabricated using Al/Ni reactive film is described. Rectangular solid Si sample with solder-bonded section was prepared for measuring the bond strength using developed four-point bending test equipment. By changing Al/Ni film thickness, interlayer between SnAg solder and Si, and pressure load during bonding, the fracture strength was investigated. In case that 10nm-thick Au/Ni was used as the interlayer, fracture occurred at the interface between the interlayer and Si. On the other hand the specimen with Au/Ni/Cr interlayer fractured at the interface between melted and non-melted SnAg solder. The strength in thick-Al/Ni specimen was higher than that in thin-Al/Ni specimen. It was found that sufficiently melting the solder during Al/Ni flash heating is important for high strength solder joint.

This research investigated advanced filling technology, different from existing technologies, for the purpose of 3D layering on electronic circuits. Filling with molten solder causes a pressure difference between the upper and lower part of the wafer, to overcome surface tension of the through via holes, and then due to pressure difference molten solder is filled into the TSV. The wafer thickness was 100–200μm with holes of diameter 20∼30μm. The TSVs were formed by deep reactive ion etching (DRIE). A wetting layer of Ti/Cu or Au was sputtered on the wall of the TSVs. Due to pressure differences between upper and lower parts, the molten solder filled into the Through Silicon Via (TSV). Vacuum Pressure was between 0.02MPa and 0.08MPa. The filling speed was under 3 seconds, much higher than conventional methods. Cross-sectional micrographs were taken with a field emission second electron microscope (FE-SEM).

The world's largest 450MVA STATCOM using GCT(Gate Commutated Turn-off) thyristor is designed for installation plan at Toshin substation of Chubu Electric Power Co. in Japan. The main purposes of the STATCOM are improvement of the power system stability and suppression of AC over-voltage occurred after route outage fault at heavy load condition. This paper describes the determination procedure of specification requirements and a system configuration. Also this paper reports simulation results for route outage fault and line-to-ground fault at nearby location of the STATCOM. STATCOM performance is verified by these simulation results.

In order to accurately evaluate spatial processing techniques such as MIMO for wideband mobile communications, a Time-Spatial Propagation (TSP) model that can simulate, at the same time, the characteristics of both the delay profile and the spatial arrival angular profile for travelling waves is required. We proposed the TSP model for wideband mobile communication systems using UHF and SHF bands in Non-line of sight (NLOS). Based on the proposed TSP model for NLOS environments, we proposed a TSP model for Line of Sight (LOS) environment. Unfortunately, its application range relating to the location of base station was somewhat restricted. This paper proposes an extended TSP model for LOS environments that covers more LOS environments.

Recent progresses in gyrotron development and related technologies are presented. The gyrotron demonstrated ITER relevant parameters at 170 GHz (1 MW, 800 s, 55 %), and proved a reliability with long operation period. Recently, one hour operation was obtained at 0.8 MW with the efficiency of 57 %, and total output energy of 190 GJ was recorded with 2 years operation. On the other hand, a power increase of 110 GHz gyrotron up to 1.5 MW was demonstrated on the electron cyclotron heating and current drive system of JT-60U.

More customers are now communicating via cellular phones in indoor environments. In such a situation, the terminals frequently remain static while being used. In order to evaluate the QoS of such terminals, a channel model that takes account of stationary usage is required. This paper proposes a channel model for static terminals in indoor NLOS and LOS environments by extending our proposed indoor NLOS channel model.

We demonstrate, for the first time, carbon nanotube (CNT) flip chip bumps for LSI modules. The CNT bump is composed of a bundle of multi-walled CNTs. Resilient and flexible CNT bumps make flip chip LSI modules resistant to thermal stress. Furthermore, CNT bumps have a low electrical resistance and robustness over electromigration. In the experiment, the CNT bumps were used to connect a test evaluation group (TEG) chip and a host substrate, and their electrical resistance was evaluated. We found that the electrical contacts of CNT bumps with the chip and the substrate are important. For a good electrical contact, the CNT bumps were coated with gold and fixed to the chip and substrate. The resultant CNT bump with a diameter of 170 mum and a height of 100 mum exhibited a low resistance of 2.3 Omega. We then evaluated the flexibility of CNT bumps by pressing the TEG chip and measuring the displacement. The displacement between the TEG chip and host substrate was 10-20% of the bump height, demonstrating an excellent flexibility.

This paper describes the study of the DNA markers of uncultured microorganisms in order to develop the technology for detecting methane leakage in the deep sea. Methane oxidizing bacteria called methanotrophs consume methane as their sole energy and carbon source and are distributed at methane producing sites. Aerobic methanotrophic bacteria use soluble methane monooxygenases (sMMO) or particulate methane monooxygenases (pMMO) to convert methane to methanol. The anaerobic oxidation of methane mediated by anaerobic methanotrophs (ANME) and sulphate-reducing bacteria plays a critical role in anoxic sediments of cold seeps. Methanotrophs are ubiquitous in soil, fresh water and the open ocean but have not been well characterized in deep-sea hydrocarbon seeps and gas hydrates, where methane is unusually abundant. In the last few decades, cultivation-independent molecular methods have been applied widely to investigate microbial diversity and quantify predominant organisms in natural microbial community. Methanotroph diversity has been studied in different environments using the polymerase chain reaction (PCR). Our goal in this study was to compare the composition of bacterial and archaeal communities associated with gas hydrates with those of bacterial and archaeal communities in normal marine sediments in the Nankai Trough of Japan in order to identify specific DNA markers (16S RNA and pmoA genes) for methane leakage in the deep sea. The development of in-situ detection of DNA markers associated with methane leakage is now ongoing with the application of a totally integrated and automated system for in-situ gene analysis of microbes (IISA-gene system).

A coastal sea is affected by directly material load from the land area. Especially the northeastern part of Osaka Bay which adjoins the urban area, Osaka, Kobe and so on is eutrophic sea, because there are much material loading and a few seawater exchanges due to the reclamation and the breakwater. Omae beach is natural beach and is located in the Shuku River mouth in Nishinomiya City. Groundwater in the seaside part of Nishinomiya City is abundant. Therefore, it is considered that the submarine fresh groundwater is discharged from the sea bottom of the coastal zone of the Omae beach. In this study, we will discuss the physical structure of the area based on the marine observation data. The stratification is developed and the horizontal flow from the southern side dominates in the area. Water exchange by flow dominates in the area. SFG discharge is 53% of the discharge of the Shuku River. But TP discharge from SFG is 7.6 times of the TP discharge from the Shuku Rive. Effect of the SFG to the whole of the area may be small. But it will have the influence to the inter-tidal zone. The bio-chemical distribution is affected by the physical structure.

High quality lanthanum-modified lead zirconate titanate (PLZT) and strontium titanate (STO) thin films were deposited on sapphire substrates using an advanced sol-gel method. This new deposition technique brought high quality epitaxial growth of PLZT thin films on r-cut sapphire and STO thin films on c-cut sapphires. The PLZT film showed high electro-optic (EO) coefficients that were almost comparable to those of bulk PLZTs. In turn, doped STO thin films showed less conductivity compared to that of bulk. This may come from the existence of the grain boundaries in the STO thin films. Further improvement is under investigation in order to achieve higher conductivity of the STO thin films

More customers are now communicating via cellular phones in indoor environments. In such a situation, the terminals frequently remain static while being used. In order to evaluate the QoS of such terminals, a channel model that takes account of stationary usage is required. This paper proposes a channel model for static terminals used in indoor NLOS environments.

This paper proposes a self-test method of dynamically reconfigurable processors (DRPs) without area overhead. This method constructs a test frame of processor elements (PEs) such that it consists of test pattern generators, response analyzers and PEs under test, and switches several test frames dynamically so as to test all the PEs. Since the number of contexts and test application time are subject to the structure of test frames, we design several test frames with different structures and discuss the relationship of the structures to the number of contexts and test application time. Based on this discussion, we can construct the best test frame according to a given test environment.

Arrival angular profile model is necessary to evaluate accurately the spatial processing techniques such as adaptive array antenna (AAA) and multi-input-multi-output (MIMO). Existing models do not always predict the actual values accurately in various environments. In this paper, we propose a novel empirical arrival angular profile prediction formula that can consider the distance from BS, antenna height of the base station, and city structure (building height) generated from the data measured in various field environments. As the proposed formula is a relatively simple equation and can predict the spatial correlation accurately, it is convenient and useful for evaluating the characteristics of radio transmission systems such as MIMO and AAA, etc. in various areas.

A new approach for real time digital feedback control of PWM inverter is proposed, in which a quasi multi-rate deadbeat control combined with variable sampling method using FPGA based hardware controller. It was reported that the deadbeat control method with FPGA based hardware controller had the very good transient response for various loads, but these reports were mainly focused on a few KW class PWM inverter system, so the high carrier frequency were adopted. But in MW class PWM inverter system, the carrier frequency is limited up to 2 kHz range, because of the performance of the switching devices and the trade off against the efficiency of the inverter. In this condition, the controllability of the PWM inverter is not so much expected. In the proposed method, to ensure the tracking accuracy of the output voltage to the reference voltage, more than two sampled data is used while one carrier interval. The control characteristics of the proposed variable sampling deadbeat control is verified through simulations and experiments.

We have newly developed an 80 MVA GCT STATCOM for the Kanzaki substation of the Kansai Electric Power Co., Inc. It started commercial operation in June, 2004. The main purpose of the STATCOM is to maintain voltage during single circuit connection of source to the substation resulting from an AC system fault in order not to break down load system of the substation. The developed STATCOM has three distinctive features: (1) a high-efficient, compact and AC filter-less system using multistage three-level GCT converter and customized PWM; (2) a coordinated voltage regulator with tap control of main transformers; and (3) a continuous operation from a single phase-ground fault through reclosing of the faulted circuit by limiter adjustments of the reactive current reference. This paper describes characteristics of the coordinated voltage and validity the continuous operation during AC system faults using data of commercial operations and the simulation results.

In wireless mesh network for accessing to the Internet, the target of all traffic generated from distributed nodes is a gateway (GW). Therefore, many packets are concentrated around the GW, and the communication channel around the GW is overloaded. In this paper, in order to avoid the congestion around the GW, we consider an adaptive array antenna setting on the GW and relay nodes. By using an adaptive array antenna, the received two or more signals can be demodulated at the same time and the network capacity around the GW can be improved. The number of simultaneously demodulated signals is decided by the number of antenna elements. However, to improve the throughput of the entire network, a redundant number of antenna elements boosts a further load at the particular nodes and generates novel bottleneck nodes. Then, we propose a balance improvement design of the number of antenna elements setting up in each node. By using the computer simulation, we confirm the performance improvement of the proposed system with appropriate number of multi-antenna.

This paper presents structures of artificial coplanar waveguide (CPW) with very slow phase velocity and their applications to a design of compact rat-race and branch-line hybrids. The slow-wave structure is constructed by periodically loading a CPW with simultaneous series inductance and shunt capacitance, and a meaningful reduction of the effective wavelength for a Bloch wave is achieved along with an adequate Bloch impedance. Next, a rat-race and a branch-line hybrid are designed using the artificial CPW's, and consequently considerable size- reduction of about 1/2 to 1/4 is obtained.

RF systems of ECH, LH, ICH, and positive and negative ion based NBI systems are equipped in JT-60U to realize highly integrated performance plasma. Their performance and development are presented. The ECH system with the total output of 4 MW at 110 GHz has been developed using four 1 MW gyrotrons. The gyrotron has achieved 1 MW, 5 sec output of the designed value by suppressing the parasitic oscillation with SiC RF absorber built-in. Moreover, 13 MW, 1.5 s output has been attained up to now. A real time system has been developed to stabilize neoclassical tearing mode (NTM) by controlling EC beams, which consists of the ECE measurement system, JT-60 real time processor and ECH system with steerable mirror antennas. This system successfully works to suppress NTMs. The LH launcher mouth was improved for longer pulse operation 30-60 s. The grill mouth made of carbon materials was joined onto the original mouth. Injection performance of the negative-ion based NBI system has been improved by correcting beamlet deflection due to beamlet-beamlet repulsion by space charge effect. This was compensated by a focusing electric field that was made by modification of extractor segment edges. Then, injection of 2.6 MW, 10 s has been achieved reducing temperature rise of the beam limiter by /spl sim/70%.

In this paper, we address simultaneous stabilization problem for a triple of linear systems within a behavioral framework. First, we provide a necessary and sufficient condition for a given pair of linear systems to be simultaneously stabilizable in a behavioral framework. Next, we show that a simultaneous stabilizer has a symmetric structure, which is also a self-standing interesting result from the theoretical points of view. By using these results, we give a new necessary and sufficient condition for a given pair of linear systems to be simultaneously stabilizable. This new condition is described in terms of the solvability of polynomial matrix equations consisting of polynomial matrices inducing kernel or image representations of the behaviors of given two behaviors. Finally, by using this new condition, we give a sufficient condition for a triple of linear systems to be simultaneously stabilizable in terms of the behaviors.

In this paper, we address the discrete time deterministic Kalman filtering within a behavioral setting. In the continuous time case, Fagnani and Willems developed this issue by using the novel idea based on two-variable polynomial matrices and quadratic differential forms in [1] and [12]. We expand the Kalman filtering problem into the discrete time case by using two-variable di-polynomial matrices and quadratic difference forms studied in [3], [4] and [5]. Here we derive a sufficient condition for the latent variables of the filter to estimate the observed data and the state variable of the system in the sense that the sum of squared error signals between observed variables and estimated ones is minimized deterministically. By using this condition, we then clarify the structure of the optimal filter with respect to the notion of the state. And then we also provide the procedure for implementing the optimal filter as a real-time algorithm. Finally, we give an illustrative example in order to show the validity of our results.

By using on-chip lenses and fluidic operations to control focal length and direction of a laser beam, two kind of new concepts are proposed in the paper. One is a device to generate and control micro bubbles inside a microfluidic chip. Second is a new optical paths control method by microfluidic operation. To demonstrate the functionality of the optical paths control, the present method was utilized for optical tweezers applications.

In this paper, we proposed a common-control channel construction for SCS-MC-CDMA systems. By multiplexing a narrow-band common-control channel into traffic channels, in the standby mode, the mobile stations (MS) needs to receive only the narrowband common-control channel, which leads to lower power consumption. Moreover, with the proposed channel construction, the cell search algorithm becomes simple. Cell specification is accomplished by simply measuring sub-carriers that are common-control channel candidates. The long code necessary for the traffic channel is received as a data from the common-control channel. We evaluated communication quality of common-control and traffic channels through computer simulations. By setting the transmitted power ratio of common-control to traffic channel appropriately, sufficient communication quality is accomplished in both channels

In order to accurately assess spatial processing techniques such as Adaptive Array Antenna (AAA) and MIMO for wideband mobile communications, we proposed a time-spatial path model that allows the delay profile and angle profile of the traveling wave to be simulated at the same time. In order to explain the field measurement results in various environments, this paper proposes an advanced time-spatial path model that uses several attenuation factors instead of the one attenuation factor used in our previous proposal.

The JT-60U gyrotron has a triode electron gun, which enables to control its oscillation output by adjusting its anode voltage. The output was successfully recovered by anode voltage control when it was terminated. Moreover, the output was modulated at 0.7 MW up to 500 Hz with modulation factor 80 %.

This paper presents a design technique of a broadband CPW branch-line 3-dB coupler with open-circuited quarter-wavelength series-stubs added at each port as a matching network. After describing the design concept, a coupler with series-stubs constructed inside the central strip of each CPW port is designed and a good hybrid performance over a fairly wide bandwidth of 31 percent or more is demonstrated by em-simulations and experiments. In addition, downsizing is attempted by the use of reactive loading onto the series-stubs and the ring line sections, and successfully achieved without destroying the broadband properties.

This paper presents a new quarter-wavelength microstrip coupler with high directivity, which consists of a periodic sequence of floating metal strips in the slots on the inner edges. After describing the characteristics of the coupled-line, a 15-dB coupler is designed and a high directivity of 30 dB or more in theory is obtained over a considerably wide bandwidth. The validity of the design concept is confirmed by em-simulations and experiments.

We have developed and experimentally demonstrated a microbioreactor embedded with stirrer-type micropumps for on-chip perfusion of culture medium and optical fiber connectors for on-chip and real-time fluorescent detection. The cell culture chamber was separated two compartments by a polyester-made semi-permeable membrane, which can realize polarized cell culture condition and detection of fluorescent movement in-between the two-compartments. As an evaluation of the microbioreactor, it was measured that Rhodamine-123 movement by the activity of P-glycoprotein of a small intestine model cell of Caco-2. As a result, the change of fluorescent intensity of Rhodamine-123 from basolateral side to apical side of Caco-2 cells was successfully detected.

Superconducting combined function magnets will be utilized for the 50 GeV, 750 kW proton beam line for the J-PARC neutrino experiment. The magnet is designed to provide a dipole field of 2.6 T combined with a quadrupole field of 19 T/m in a coil aperture of 173.4 mm at a nominal current of 7345 A. Two full-scale prototype magnets to verify the magnet performance were successfully developed. The first prototype experienced no training quench during the excitation test and good field quality was confirmed.

In a prior paper we proposed an SCS-MC-CDMA (Sub-Carrier Selecting Multi-Carrier Code Division Multiple Access) system that reduces the signal processing load at the mobile terminal. This paper proposes a novel HARQ (Hybrid Automatic Repeat reQuest) method with significantly improved throughput performance for this system. In the proposed method, the symbols of an original packet are retransmitted on different sub-carriers with low correlation levels in the frequency domain, and the receiver combines the symbols in the original and retransmitted packets. Combining the symbols received through a fading channel with a low correlation level yields a high diversity effect in the time domain under slow fading. We carry out a computer simulation to estimate the proposed method's performance when the primary modulation is 16 QAM. The simulation results show that the proposed method has more than 5 times the throughput of of the conventional method with Chase combining at an averaged Eb/N0 of 6 dB when the primary modulation is 16 QAM. frequency is low. To solve the above problem, in this paper, we propose a novel HARQ method for the SCS-MC-CDMA system that offers significantly improved throughput even if the maximum Doppler frequency is low. In many cases, high data rate services are used in low mobility situations: the proposed method is especially valuable to provide such services. Note that the proposed method can be also applied to other wireless systems based on multi-carrier modulation such as OFDM systems.

In this paper, as one of the synthesis method of a linear canonical controller (this is a controller that satisfies the obtained data and a given specification simultaneously), we provide a new tuning method of such a controller. The tuning method we proposed in this requires only one-shot closed loop experimental data and yields all of the parameters of a linear controller so as to minimize the performance index by using the least squares optimization directly, i.e., without a mathematical model of a plant. We also give an illustrative example in order to show the validity of our method

PID control schemes have been widely used in most process industries. Since the control performance strongly depends on PID parameters, it is important to suitably choose a set of these parameters. Especially, it is difficult to determine these parameters in the case where the time-delay is unknown and/or large. On the other hand, it is well-known that the generalized predictive control(GPC) effectively works for such systems. Then, a new PID tuning scheme(GPC-PID) which is derived from the relationship between the GPC and the PID control laws is proposed in this paper. Furthermore, the implementation of the GPC- PID for the existing PID auto-tuner is considered. A consideration on determining the user-specified parameter included in the GPC-PID, is also considered. Finally, the GPC-PID is tentatively implemented in the existing thermoregulator, and the behavior is experimentally examined.

In this paper, we propose a new identification method that so as to yeild parameters of a plant by tuning a controller including a nominal plant model. Some of the authors previously have proposed fictitious reference iterative tuning (which is abbreviated to as FRIT[1]) as one of the useful and rational tuning methods of controllers. It enables us to obtain the optimal parameter of a controller based on only one-shot closed loop experiment data and an off-line nonlinear optimization. We apply FRIT to identify the dynamics of a plant in the closed loop by tuning the controller including the parameters of a plant. As a result, it is possible to obtain the parameters of a plant as well as the optimal parameters of a controller. In order to show the simplicity and usefulness of this method in practical sense, we apply such a new method to identify parameters of a cart system.

We introduce a novel biosensor device for various biocell measurements by singular cell level with parallel analysis and high throughput. This paper deals with the details of its fabrication, including device packaging, and the practical measurement of red blood cells using a twin microcantilever type sensor array. Based on a simple measurement of the electrical impedance of a living single red blood cell and its suspension, an important set of data, which can be used to describe living matter, could be obtained.

This work discusses thermal designing and performance of a compact type AMTEC system. The compact type AMTEC system uses multiple small-sized cell components, which consist of sodium beta-alumina solid electrolyte tubes of 3 mm in outer diameter and simple freestanding type capillary structure. When the cell components are arranged in a canister, the pressure drop due to sodium vapor flow from the electrode to the condenser becomes a critical parameter. The effect of the pressure drop was analytically evaluated and the optimum geometrical arrangement was considered. The typical calculated result shows that a 37-tube cell having a base area of 7.5 cm/sup 2/ has a predicted output power of about 5 W at relatively low operating temperature of 900 K. This output power is almost equal to that of the high temperature type cells operating around 1,100 K. Structure and heat transfer analyses necessary for the miniaturization and the low temperature operation are reported in this paper. Preliminary thermal design on a cascaded system with the AMTEC and the thermionic converter is also discussed.

A flowing electrolyte zinc/bromine battery is one of several advanced batteries for electric power storage currently under development by MEIDENSHA and the New Energy Industrial Technology Development Organization(NEDO) sponsored by the Ministry of International Trade and Industry(MITI) in Japan(1). The advantages of this battery include high energy density and an abundant availability of materials, Other features of the zinc/bromine battery include: (1) An aqueous-electrolyte battery operated at ambient temperature and is characterized by easy maintenance control. (2) The battery's conductive carbon- plastic electrode(CP electrode) makes it suitable for large capacity application and for mass production at low cost. (3) With small numbers of components based on simple battery reactions, it is compact and can be assembled easily. We have designed a IMW(4MWh) class battery system for a battery storage test facility at Imajyuku substation of the Kyushu Electric Power Company. This 1MW class battery system is constructed 24, 25kW sub-module batteries in series connection. These batteries are scheduled for installation from June 1990, and the facility will be operation by the end of this year. Before installation, these batteries will be tested by MEIDENSHA. Additionally, we have begun life-cycle test and an accelerated life-cycle testing of 3kW and 0.3kW class battery, respectively. We have indicated that the life of zinc/bromine battery is dependent upon the durability of CP electrode. In an effort to improve this electrode, we have analyzed physical and chemical characteristics of the deteriorated electrode.

We have introduced a new biosensor device for red blood cell measurement by singular cell level with parallel analysis and high throughput. This paper deals with the practical measurement of red blood cells as well as the details on its fabrication, including device packaging. Based on a simple measurement of the electrical impedance of a living single red blood cell and its suspension, an important set of data, which can be used to describe living matter, could be obtained. It was confirmed that the electrical impedance between normal and abnormal red blood cells was significantly different in magnitude and phase shift.

Low temperature measurement of infrared spectra was proposed in the present study for highly sensitive determination of biochemical substances in aqueous solutions. Infrared absorption by glucose was enhanced more than tenfold compared with that at room temperature by lowering the temperature to about -20 OC. The proposed method offers a possibility for quantitative analyses of biochemical substances with high sensitivity based on the ATR/FT-IR technique.

The major two demands against electronic devices are smaller dimension and higher performance (higher data rate). In terms of packaging technology, flip chip interconnection is one of the currently available solutions that meet those demands by providing high density and low inductance interconnection between chip and system. However, this technology has a limit for fine pitch, which should be ~10um. As an alternative to achieve finer pitch interconnection, we have investigated bumpless interconnection. In this research, we have succeeded in bonding a Si chip to a flexible substrate. Flexible substrates will enable electronic devices become smaller, and are already used for mobile applications in a large volume. A shortcoming of high-density interconnection is that, cross talk noise will become dominant as the spacing between adjacent signal lines will become smaller. To avoid this problem, we have applied a pair line transmission line structure for the interconnection. We got the electrical performance of 3GHz pulse frequency through as many as 196 bumpless interconnections of daisy chain on this experimental system.