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This paper proposes a new equivalent circuit for induction motors having the harmonic components. The proposed circuit consists of T-type equivalent circuit and LC resonant circuit, which is connected in parallel with load resistance. Various features of the induction motors including harmonics can be easily obtained by the proposed circuit. The fundamental component is expressed by the conventional output resistance, and the ripple elements of the mechanical output are represented by the current flowing in the LC parallel resonant circuit. In the proposed equivalent circuit, the current flowing into the load resistance becomes sinusoidal, so that we can separate ripple components from fundamental one. It is necessary to decide the appropriate values of L and C as the resonant frequency that gives the fundamental frequency. Strictly speaking, the resonant frequency is denoted by rotor speed. By means of this circuit, various harmonic torque characteristics can be easily obtained.

A magnetic force has been used to control a partially magnetized atomic force microscope cantilever in ultrahigh vacuum in order to investigate tip-surface interactions. It is shown that forces applied by an oscillating tip can drastically affect the measured response of the lever. In particular the oscillating force influences the measured tip-surface adhesion and can be treated as a simple addition to the static applied force in breaking adhesive bonds. Qualitative differences in force spectroscopy measurements due to the amplitude of the driving oscillation of the lever are presented and an alternative nonintrusive technique introduced.

The Brazilian Stroke Society constituted a committee composed by specialists from different areas of Brazil that emitted a viewpoint called "National Opinion", written similar to the consensus pattern. The study purpose is to guide and offer subsidies for diagnosis and therapeutical plans for different situations in cerebrovascular diseases. The current article analyses "neuroprotective agents in stroke", discussing the level of evidence for the use of potential neuroprotective drugs and ongoing clinical trials.

Capacitor input-type rectifier circuits are generally employed in small-capacity rectifier circuits, such as those used for consumer electronics and appliances. Consequently, the various harmonics that are generated in the power system become a serious problem. Various studies of these issues have been reported. However, most of those methods employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings other benefits in terms of low EMI noise. We propose a power factor correction scheme using cycle-control for commercial frequencies without the need for high frequency switching devices, in this paper, we attempted to use a passive element including a proposed novel PFC circuit that includes cycle-control to obtain a reduced output voltage. In order to avoid the generation of various harmful harmonics during cycle-control, a novel divided capacitor-type rectifier circuit is proposed. It is very easy to reduce the harmonics in this circuit. The results are confirmed by simulated and experimental implementations

This paper reports 65-nm node ultra-low standby power CMOS technology for mobile applications, utilizing the combination of HfSiON FET and back-biasing scheme for the first time. With well-optimized channel, offset-spacer and halo conditions, physical gate length is successfully scaled down to 55 nm with excellent V/sub th/ roll-off and small DIBL, for both surface channel nFET and buried channel pFET. The record I/sub on//I/sub off/ ratio, the drive current of 510/220 /spl mu/A//spl mu/m with off-state leakage of 20/20 pA//spl mu/m, are obtained. We have also demonstrated body-biasing scheme feasibility for further subthreshold leakage (I/sub subth/) reduction. By exploiting Fermi-level-pinning effect, we have reduced the channel doping concentration and suppressed gate induced drain leakage (I/sub GIDL/) even under reverse body-biasing condition. Total standby leakage (I/sub subth/+I/sub GIDL/+I/sub g/) are reduced to 1.4/0.32 pA//spl mu/m at V/sub dd/= 0.8 V and Vb= /spl plusmn/1 V, which is the smallest value ever reported for 65nm-node LSTP.

In the fields such as various electric power compensators and ac motor drives, large capacity and high-performance converters are placed into practical applications. For these converters, since the upper limit of the switching frequency is low and capacity of device is insufficient, method of connecting the device in series and parallel would be effective. From such reasons, for improving the harmonic characteristics, various multi-level inverters have been reported, in which it is necessary to provide some dc power supplies connected in series that is disadvantage for this inverter. We propose a simple dc-dc converter for adjusting the power supply voltages of this inverter. By means of this dc-dc converter circuit, the voltages of four dc power supplies of five-level inverter can be suitably controlled towards the desired value. The circuit characteristics are discussed by theoretical and simulated procedures. The theoretical results and the simulated ones are in agreement with each other.

The conventional boost converters can be generally used for rectifier circuits with power factor correction, while the output voltage can not be adjusted over a wide range. In a case of expanding the controlled voltage range, buck-boost type including Cuk converter should be employed. This paper discusses an optimum circuit configuration for power factor correction. Single-phase power factor correction using a buck boost converter can control the output voltage over a wide range, because it has the ability to step-up and step-down the output voltage. Firstly, this paper compares the mechanisms of the proposed power transmission technique and the characteristics based on the voltage and the current ripple in terms of EMI noise. Secondly, these converters are applied to the single-phase power factor correction. It is found that the CSC (Canonical Switching Cell) is the best choice and selected as the optimum PFC.

For various electronic equipments including both analog and digital circuits, sometimes requires power supplies with different supply voltages. We propose a novel chopper, with simple circuit configuration, which can supply to two or more different output loads. This converter provides wide control output voltages by varying duty ratio using switching devices.

Capacitor input-type rectifier circuits are generally employed in small-capacity rectifier circuits, such as those used for consumer electronics and appliances. Consequently, the various harmonics that are generated in the power system become a serious problem. Various studies of these issues have been reported. However, most of those methods employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings other benefits in terms of low EMI noise. We propose a power factor correction scheme using cycle-control for commercial frequencies without the need for high frequency switching devices. It is very easy to reduce the harmonics in this circuit. The results are confirmed by simulated and experimental implementations

The five-level PWM inverter has many advantages such as ability to operate the AC motors or the power compensator with very large capacity in nearly sinusoidal current waveforms. For these reasons, these applications have just begun to study. However, this circuit must provide four DC power supplies for supplying the active power. In this paper, we propose a novel double power supply method, in which both power supplies are interconnected by DC capacitors. The voltages of the interconnected DC capacitor are controlled by a novel third order harmonic injection method, where the phase of modified third order harmonic signal having positive or negative polarity is controlled individually

The line impedance could be measured by means of only passive elements such as inductors or resistors, that is presented at first. However, as the voltage and current used for the measurement are increased, the size of the inductor or resistor being used also needs to be increased, so in practice it would be virtually impossible to make an accurate measurement. Because of this, we have developed a novel measurement method for line impedance using an inverter circuit, which we describe secondly. In the third place, we propose another line impedance measurement method. The novel method is that the high frequency wave with minimum voltage is injected into the distribution line system. By means of this method, the line capacitance and the line inductance can be measured. These proposals are confirmed by the simulation or experiment

THE bonding potential between atoms determines all the key properties of matter. It is usually deduced from a wide variety of experimental parameters such as elastic moduli, binding energy and vibrational nonlinearities. These provide an indirect route to quantities such as virial coefficients which characterize the variation of potential energy with interatomic spacing1. Here we report use of a modified atomic force microscope2 to measure mechanically the interatomic forces between a tip and the sample surface as a function of separation. We use a magnetically controlled feedback mechanism to resist the 'jump to contact' that commonly occurs in mechanical force measurements at small separations, enabling us to map out reversible curves to separations closer than the point of inflection in the potential-energy curve. This method provides a direct means for continuous measurement of forces between atoms as they approach towards contact.

In the fields such as various electric power compensators and ac motor drives, large capacity and high-performance converters are wished to be put into practical applications. For these converters, since the upper limit of the switching frequency is low and capacity of device is insufficient, method of connecting the device in series and parallel would be effective. From such reasons, for improving the harmonic characteristics, various multi-level inverters have been reported, in which it is necessary to provide some dc power supplies connected in series that is disadvantage for this inverter. We propose a simple dc-dc converter for adjusting the power supply voltages of this inverter. By means of this dc-dc converter circuit, the voltages of four dc power supplies of five-level inverter can be suitably controlled towards a desired value. The circuit characteristics are discussed by theoretical and simulated procedures. The theoretical results and the simulated ones agree with each other.

2,2-bis (4-hydroxyphenyl) propane or Bisphenol A (BPA), has been reported to behave as an endocrine disrupter below acute toxic levels, and is widely present in the water environment. Although BPA is easily chlorinated, very little is reported on the effect of chlorinated BPA to the aquatic organisms. In this study, the estrogenic activities of BPA and its chlorinated derivatives were evaluated by the induction of vitellogenin (VTG) in the serum of mature male Japanese medaka. In addition, the effect of sodium hypochlorite on the decomposition of BPA was tested. The relative potencies of estrogenic activities of chlorinated BPA descended in the order 3,3'-diCIBPABPAor =3-CIBPA3,3',5-triCIBPA, and no estrogenic activity was observed in 3,3',5,5'-tetraCIBPA. Lowest Observed Effect Concentration (LOEC) and No Observed Effect Concentration (NOEC) for both 3-CIBPA and 3,3'-diCIBPA were 500 microg/L and 200 microg/L, respectively. LOEC for 3,3',5-triCIBPA was500 microg/L. When BPA was reacted with sodium hypochlorite (24 hours; residual chlorine at 1 ppm), however, complete decomposition of BPA and its chlorinated derivatives was observed. The decrease in BPA and its chlorinated derivatives paralleled the decrease in estrogenic potency evaluated by the induction of vitellogenin (VTG) in the serum of mature male Japanese medaka.

The authors propose a 120-degree beamwidth slot array antenna with a three-way power divider using post-wall waveguides installed on a single-layer substrate. The antenna is designed for base stations in 26 GHz-band fixed wireless access systems (FWA). It is easily manufactured at low cost for mass production by making via-holes and metal plating for the post-wall waveguides and etching for the slot array. In the vertical plane, a cosecant beam pattern is synthesized with null filling in order to get uniform illumination over the coverage area.

The characteristic feature of subcooled film boiling in He II was experimentally studied. The visual observation and the transient pressure and temperature measurements were performed to investigate the variation of the subcooled film boiling state with the pressure. In the highly subcooled state, the boiling state was relatively stable and little dynamic behavior of the vapor layer was observed. The pressure and temperature oscillations were hardly detected. As the pressure is reduced and consequently the degree of subcooling decreases, the thickness of vapor layer becomes thick and the dynamic behavior gradually becomes violent. The pressure and temperature oscillations appear with a very high frequency around several kHz. As the pressure further decreases to near the lambda pressure, the boiling state changes to much more violent boiling state with a frequency of several hundred Hz. A vapor bubble repeats formation and crush periodically, which apparently resembles noisy film boiling in saturated He II. The boundary between the stable and the unstable boilings seems to be in the pressure higher than the lambda pressure.

We have newly developed poly-Si/a-Si/HfSiON (EOT=1.6nm) transistor that features high I/sub on/-I/sub standby/ ratio and reliability for 65nm-node LSTP (Low Standby Power) application. By carefully optimizing halo implant condition, excellent I/sub on/-I/sub standby/ (=I/sub g/I/sub off/) characteristics of I/sub on/=520/spl mu/A/I/sub standby/=17pA (I/sub g/=1.6pA, I/sub off/= 15pA) at V/sub dd/=1.2V are obtained, which is the highest ratio ever reported. In addition, we have newly introduced thin amorphous-Si layer between HfSiON and phosphorous-doped poly-Si gate-electrode for reliability enhancement, and confirmed that PBTI (positive bias temperature instability) lifetime improves by two orders of magnitude with no performance degradation. We believe this technology enables further device scaling of poly-Si/HfSiON structure.

In this research, to analyze "a feeling of unity" at a concert hall, we investigated the relationship among listener's respiration and handclap and the music. As a result, it was shown that listener's respiration and handclap preceded to musical note. This result suggests that the predictive actions have influence to listener's subjective mental condition.

The conventional boost converters are generally used for rectifier circuits with power factor correction, and as a result the output voltage becomes limited. To expand the controlled voltage range, buck-boost or Cuk converter types should be utilized. This paper presents a circuit configuration with power factor correction by a third type of buck boost converter, termed a 'CSC, canonical switching cell'. Single-phase power factor correction using a buck boost converter can control the output voltage over a wide range, because it has the ability to step-up and step-down the output voltage. Firstly, this paper compares the mechanisms of the power transmission and the characteristics based on total stored energy. Secondly, CSC converter is applied to the single-phase power factor correction. It is presented that this converter is suitable for power factor correction.

Multi-level PWM inverters, (including five-level ones), have significant operational advantage, such as the ability to drive a motor with nearly sinusoidal current waveforms and at higher output voltages. Consequently, the consideration of their practical applications is of increasing interest. When we look in detail at their possibility, the requirement for larger capacity inverters is also anticipated for use in large AC motor drives, SVCs (static VAr compensators) and the like. In this paper, the possibility of applying the technology to SVCs is discussed. By controlling the phase and the amplitude of the modulating sinusoidal signal, the capacitor voltage and the output current can be controlled successfully, which can play an important role in SVC applications. In addition, a third order harmonic can be injected, and the capacitor voltage can be controlled by shifting its phase with reference to the modulating sinusoidal waveform. By using these characteristics, coupled with an adequate feedback control circuit, each capacitor voltage can be controlled, even with respect to fluctuations in the load or unbalanced states of the individual capacitor voltages.

It has been demonstrated that patients with asthma have a large number of NK cells and show a stronger NK activity. These results indicate that NK cell activity may be related to total IgE level in serum in healthy subjects. Previously, we have found that sodium butyrate (NaBu) markedly enhanced the IL-4-induced IgE production in the LPS-stimulated murine splenocytes in vitro, and inductive rat IgE production in vivo, and enhanced the NK cell activity ex vivo. We hypothesized that the IgE production might be involved in butyrate-enhanced NK cell activity in vivo. Mice were intraperitoneally treated/immunized with NaBu or/and Ascaris suum extract (ASC), and the spleen NK cell activity was evaluated. Furthermore, the effect of serum (NAS) on IL-2- or IFN-gamma-induced spleen NK cell activity was determined. The spleen NK cell activity and IL-2- or IFN-gamma-induced spleen NK cell activity of mice treated/immunized with NaBu or/and ASC were stronger than those of untreated/unimmunized mice. Although IL-4 blocked IL-2 (100 U/ml)- or IFN-gamma (100 U/ml)-induced increase in NK cell activity, these NK cell activities in mice treated/immunized with NaBu/ASC were not inhibited. IgE production showed a tendency to rise in NaBu-treated mice serum, and a synergistic effect was observed with treatment of NaBu and ASC. Moreover, the NAS significantly increased IL-2(25 U/ml)-or IFN-gamma(25 U/ml)-induced NK cell activity, and its effect was inhibited by anti-mouse IgE mAb. These data show that IgE plays an important role in NAS-enhanced IL-2/IFN-gamma-induced NK cell activity, and IL-4 does not inhibit IgE and IL-2/IFN-gamma-induced NK cell activity in mice.

Various nonlinear semiconductor circuits have been used in consumer and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within a power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes some rectifier circuits for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

For rectifier circuits with power factor correction, boost converters are generally used, and as a result the output voltage becomes limited. To expand the controlled voltage range, buck-boost or Cuk converter types should be utilized. This paper presents a circuit configuration with power factor correction by a third type of buck boost converter, termed a canonical switching cell. Single phase power factor correction using a buck boost converter can control the output voltage over a wide range, because it has the ability to step-up and step-down the output voltage. Firstly, this paper compares the mechanisms of the power transmission and the characteristics based on the switching ripple of various converters, in which the Luo converter is added in discussion. Secondly, the canonical switching cell is applied to the single phase power factor correction. It is shown that this converter is suitable for power factor correction.

The genetic mechanism of the tumorigenesis of meningioma in conjunction with von Hippel-Lindau (VHL) disease is unclear. The authors present a case of VHL disease associated with a posterior fossa meningioma and with multiple cerebellar hemangioblastomas. A germline mutation of the VHL gene and loss of heterozygosity on the VHL gene locus in 3p were detected in the meningioma. Tumorigenesis of a meningioma associated with VHL disease could be caused by inactivation of both alleles of the VHL gene.

Crystallization behavior of amorphous chenodeoxycholic acid (CDCA) was studied using X-ray diffraction (XRD), infrared (IR) spectroscopy and differential scanning calorimetry (DSC). The two polymorphs of CDCA, form I (mp 166 degrees C) and form III (mp 119 degrees C), were ground with a vibrational mill. The ground samples of both crystal forms showed halo X-ray diffraction patterns. DSC curves of the amorphous samples derived from the form I and form III showed exothermic peaks due to the crystallization to the form I at 120 and 147 degrees C, respectively. When the ground form III was mixed with the ground form I, the crystallization temperature shifted to a lower temperature as the content of the ground form I increased. In the case of co-ground sample of form I and form III, the crystallization to form I crystals proceeded by two different modes. These results indicate that the physicochemical state was different among the ground samples of the form I and form III, and that the crystal nuclei played an important role on the crystallization process of the amorphous CDCA.

Serum prolactin increases during late embryogenesis. In order to elucidate the function of prolactin at this period, tissue distribution of prolactin receptor mRNA was examined by RNase protection assay. The mRNA was detected strongly in the kidney, intestine, and allantoic membrane; weakly detected in the brain; but not detected in the liver. The expression levels of the prolactin receptor mRNA in the kidney, intestine, and allantoic membrane were retained at constant levels during later stages of embryogenesis (Days 17 and 19) and posthatch periods (2 and 28 d after hatching). These results suggest that prolactin is mainly involved in the osmoregulation during the later stage of embryogenesis and that the expression of prolactin receptor mRNA in the kidney, intestine, and allantoic membrane is regulated by a serum prolactin-independent manner.

Multi-level PWM inverters have significant advantages such as the ability to operate the motor with nearly sinusoidal current waveforms and higher output voltages. In order to increase the inverter size, the parallel connection method would be effective for the present. In high-power applications, for instance, the carriers should be synchronized to modulating sinusoidal waves. Moreover, for the interphase reactor, lower order harmonic application is prohibited. In practice, to improve the harmonic characteristic of the parallel-connected five-level inverters, various modulation strategies are devised and designed in this paper. It is found that the DC current flow of DC power supplies can be controlled by means of phase shifting of the injected third order harmonics or modifications of them. In the case of the SVC (static VAr compensator), by means of this technique, the output capacitor voltages could be controlled individually.

A logic-process-compatible low-temperature hemispherical grain (HSG) cylinder capacitor process with maximum process temperature below 700/spl deg/C is developed. Depletion in HSG-grains and top-electrodes due to decreasing thermal budget is effectively suppressed by phosphorus doping with PH/sub 3/-annealing and the use of metal plate-electrodes. By combining with the HSG grain size optimization, the low-temperature process with highly reliable oxynitride (ON) dielectrics can be applied to high density embedded DRAM cells down to 0.13 /spl mu/m design rules.

A new method for the control system design of AGVs is proposed in the paper. The control system design can avoid a prohibited situation and a deadlock, and also evaluate the rule and AGV number. The control system is applied to the AGV of a factory production line system. Its effectiveness is confirmed by SIMAN/CINEMA simulation. >

This paper is the first report on the detrimental current crowding effect in the power grid structure of gate arrays. Innovative solutions to the problems are described. The proposed power routing technique utilizes flexible metalization with respect to the power pad locations. The resulting structure improves gate utilization and prevents metal electromigration. The CAD physical design flow for implementation in a 0.5 /spl mu/m CMOS sea-of-gate array is described. >

In recent years, the surface mounting process has become widespread in the semiconductor industry. Correspondingly, the epoxy molding compounds used for chip encapsulation have needed good reflow crack resistance in order to survive the high heat stresses of SMT. Material development engineers have continually searched for molding compound resin types that will give them optimum reliability and moldability, but at an affordable price. Biphenyl resins notably exhibit resistance to reflow cracking, but they have performance problems in terms of moldability and cost. Several variations of the conventional resin system molding compounds have been developed, but they have yet to meet the reflow crack resistance of compounds made with biphenyl resins. In light of this, we have developed new epoxy molding compounds, the KE-1800Y series, which uses the dicyclopentadien (DCPD) epoxy resin system. KE-1800Y series offers good moldability, excellent reliability and lower cost for hard to mold, thin IC packages, such as TSOPs and TQFPs. For package assemblers using the pre-plated lead-frame (PPF) assembly system, the KE-1800Y series has the option to add a proprietary class of our adhesion promoters. These additives offer high strength adhesion between the molding compound and Pd/Au or Pd pre-plated lead-frames (PPF).

The wet type plasma reactor is a new facility developed to control the emission of dioxin. Flue gases from coal-fired power plants, waste incinerator etc. contain harmful pollutants such as dioxin, NO/sub x/, SO/sub 2/ and particle matter. Many processes have been developed for the removal of such pollutants from the flue gas before release to the atmosphere. For example, a coal-fired power station utilizes selective catalytic reduction process for NO/sub x/ removal, wet or dry scrubber for SO/sub 2/ removal and electrostatic precipitator (ESP) or bag filter for the removal of particle matter. These methods have good performance but are capital intensive. An effective treatment process has been of interest especially for small-scale power generation such as co-generation system and waste incinerator system. The authors studied the gas cleaning process utilizing the DC corona discharge or pulsed discharge with a water film. We found that the wet type nonthermal plasma reactor is more effective for the gas cleaning than the dry type reactor. Dioxin removal efficiency more than 90% was obtained in this system.

We achieved a novel low voltage operating flash memory cell with high coupling ratio of 0.9 which has a horned floating gate (FG) with fine HSG. The increase in the coupling ratio can reduce programming and erasing operation voltages by a maximum 4 V. Enlargement of the FG surface area by extending in the vertical direction enables the high coupling ratio without increasing cell area. In addition, the increase in the coupling ratio is significant when cell size is shrunk. We consider the horned FG cell with HSG as the most promising candidate for the flash memory cell in 0.25 and 0.18 /spl mu/m design rules.

The purpose of this paper is to introduce the applications of neural networks to marine vehicles. The paper shows the applications for an oscillating fin propulsion control system and an underwater vehicle control system. The control algorithms based on neural network are successfully applied for these systems, and its effectiveness is confirmed.

The electrical characteristics and gate lengths of individual MOSFETs are evaluated by a test structure with a Kelvin pattern as the gate electrode. The gate length measurement by SEM can be substituted by the electrical measurement using this test structure. Excellent correspondence is obtained between the threshold voltage lowering in the short channel region and the electrically measured gate length. Furthermore, the precision of drain-to-gate overlap length is improved by applying the effective channel length extraction method to the electrically measured gate length instead of the commonly used designed gate length.

In general, the harmonics in a power system are measured with a heterodyne receiver if one is using analog methods or by a FFT (Fast Fourier Transform) when digital methods are being used. The harmonics can be analysed over a wide range of frequencies by means of these methods. However, since the circuit configurations that are needed can become very complicated, the equipment tends to be too expensive for practical use. This paper presents a novel harmonic meter using a PLL (phase locked loop) circuit. By means of the phase feedback loop, a reference sinusoidal wave is locked on to the input signal along with the harmonics that one wishes to measure, and hence the corresponding harmonic component in the input signal is easily detected. The effectiveness of the proposed harmonic meter is confirmed by experiment.

The various harmonics in a power system are typically measured with a heterodyne receiver if we are using analog methods or by a FFT (fast Fourier transform) when digital methods are being used. The harmonics can be analysed over a wide range of frequencies by means of these methods. However, since the circuit configurations that are needed can become very complicated, the equipment tends to be too expensive for practical use. This paper presents a novel harmonic meter using a PLL (phase locked loop) circuit. By means of the phase feedback loop, a reference sinusoidal wave is locked on to the input signal along with the harmonics that we wish to measure, and hence the corresponding harmonic component in the input signal is easily detected. The effectiveness of the proposed harmonic meter is confirmed by experiment.

Various nonlinear semiconductor circuits have been used in consumer electronics and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within the power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes a novel three-phase rectifier circuit for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

Various nonlinear semiconductor circuits have been used in consumer electronics and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within the power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes a novel three-phase rectifier circuit for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

Various utility-interactive photovoltaic power conditioning systems have been reported so far. In general, we could say that such photovoltaic power conditioning systems have been approaching the ideal ones, that is high efficiency, high performance and the like. However the system cost including that for power converters and solar cells still prevents widespread application. This paper proposes a simple utility-interactive photovoltaic power conditioning system with a forward converter and also proposes an innovative lossless snubber circuit, which is very easy to utilize and is suited for the this converter circuit. The system operation is confirmed by simulation analysis and experiment.

For rectifier circuits with power factor correction, boost converters are generally used, and as a result the output voltage becomes limited. To expand the controlled voltage range, buck boost or Cuk converter types should be utilized. This paper presents a circuit configuration with power factor correction by a third type of buck boost converter, termed a 'canonical switching cell'. Single-phase power factor correction using a buck boost converter can control the output voltage over a wide range, because it has the ability to step-up and step-down the output voltage. Firstly, this paper compares the mechanisms of the power transmission and the characteristics based on the switching ripple of various converters. Secondly, the canonical switching cell is applied to the single-phase power factor correction. It is proposed that this converter is suitable for power factor correction.

For small capacity rectifier circuits with a small capacity, such as those for consumer electronics and appliances, capacitor input type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been presented previously so far. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings low radio noise benefits. The authors propose a power factor correction scheme using a voltage doubler rectifier without switching devices. In this method, the input current is divided into two periods, where one period charge the small input capacitor and the other charge the large output capacitor. By dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be canceled between the two modes. Hence, the harmonic characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theoretical and experimental implementations.

For small capacity rectifier circuits with a small capacity, such as those for consumer electronics and appliances, capacitor input type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been presented previously. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings low radio noise benefits. We propose a power factor correction scheme using a voltage doubler rectifier without switching devices. In this method, the input current is divided into two periods, where one period charges the small input capacitor and the other charges the large output capacitor. By dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be cancelled between the two modes. Hence, the harmonic characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theory and experiment.

We propose sensor-based path-planning algorithms for a nonholonomic mobile robot. A car-like robot supervised by these algorithms always reaches its target point (position, and orientation) globally while sensing and avoiding uncertain neighbor obstacles locally in a 2-D environment. In general, all the classic sensor-based path-planning algorithms lead a robot to its destination (x,y) quickly in a 2-D unknown search space. Unfortunately, a nonholonomic mobile robot has three degrees-of-freedom (z,y,/spl theta/), and consequently its search space has three dimensions. In this paper, we propose two algorithms NH-I/spl middot/II. NH-I is designed by mixing modified versions of a famous model-based algorithm best-first and the classic sensor-based algorithm Class1. NH-II is designed by mixing modified versions of another famous model-based algorithm depth-first and Class1. BF and DF can investigate around an unknown obstacle whose dimensions are over two. As a result, by the mixture, we obtain three dimensional or more sensor-based path-planning algorithms NH-I/spl middot/II for a nonholonomic mobile robot. Finally, in order to check a real-time property of both algorithms, we compare their search costs with that of a model-based path-planning algorithm A/sub NH/* for a nonholonomic mobile robot.

The human ABO blood group system is important in transfusion and organ transplantation. Although the molecular basis of the ABO gene has been established, recent studies have begun to characterize the mechanism of the ABO gene expression.Transient transfection assays were carried out in human erythroleukaemia HEL cells and human gastric cancer KATOIII cells. Electrophoretic mobility shift assays were performed using nuclear extracts derived from both cells.Our characterization of the 5'-upstream sequence of the ABO genes indicated that the region between -117 and +31 is essential to direct expression of a reporter gene in erythroid cells. We show that a sequence located between positions -22 and -14 of the ABO promoter binds a ubiquitous transcription factor Sp1 or Sp1-like protein(s). Mutation of this site abrogates binding of those factors and reduces the ability of the ABO promoter to function in erythroleukaemia cells and gastric cancer cells.The expression of the ABO promoter appears to be influenced by the binding of Sp1 or Sp1-like protein(s) in both erythroid and epithelial cell lineages.

The pineal region is one of the surgically inaccessible areas in the brain. Many neurovascular structures form a formidable obstacle to the operative approach to this region. The approaches suitable for reaching the pineal region are the infratentorial supracerebellar, occipital transtentorial, posterior transcallosal, posterior transcortical and posterior subtemporal routes. Considerations important in selecting one of these surgical approaches are reviewed from the anatomical viewpoint.

The present study is based on the sample of about 3 mln single muons observed by LVD at underground Gran Sasso Laboratory during 36500 live hours from June 1992 to February 1998. We have measured the muon intensity at slant depths from 3 km w.e. to 20 km w.e. Most events are high energy downward muons produced by meson decay in the atmosphere. The analysis of these muons has revealed the power index of pion and kaon spectrum: 2.76 \pm 0.05. The reminders are horizontal muons produced by the neutrino interactions in the rock surrounding LVD. The value of this flux is obtained. The results are compared with Monte Carlo simulations and the world data., Comment: 13 pages, 2 figures, accepted for publication in "Physics of Atomic Nuclei"

The genomic organization of Tcf23, the gene coding for mouse OUT, a basic helix-loop-helix transcription factor, was determined and its chromosome location was assigned to the A3 region of chromosome 5. By in silico searching, we further found the human counterpart of the mouse OUT gene (TCF23) in the draft human genome sequence and assigned it to 2p24--p23.