bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of steady‐state characteristics in a push‐pull current‐fed high‐power factor converter using a two‐input‐winding transformer technique
Authors: Takeuchi Akira , Ohtsu Satoshi , Muroyama Seiichi
Published: July 2007

A two‐input winding transformer technique for high‐power factor converters has been developed. This technique results in reduced size and enhanced conversion efficiency. Input‐current wave‐shaping and fast output‐voltage regulation are achieved by controlling charge and discharge of an energy‐storage capacitor on the primary side of the transformer to compensate for the difference between the ac input and the dc output power. Thus, most of the input power is supplied to the output through only a single conversion stage and the low‐frequency ripple in the output voltage can be reduced with a small output capacitor. In addition, operation in the continuous conduction mode makes it possible to reduce the size of the input filter, concomitantly decreasing conduction loss.

This paper discusses a push‐pull current‐fed converter that uses this technique. In this circuit, it is necessary to restrict the pulsewidth for the input current control because the pulsewidth for the output voltage control should be expanded to decrease the rms value of the current flowing in the switches. The characteristics of input current distortion caused by this restriction are analyzed and optimization, which takes into account harmonic current characteristics and reduction of conduction loss, is clarified. High‐power factor and an efficiency of 88 percent were achieved experimentally.
Traveling‐wave microwave power combiner
Authors: Nogi Shigeji , Shimura Tatsuhiro , Fukui Kiyoshi
Published: July 2007

This paper discusses the design and characteristics of power combining and power dividing‐combining by means of traveling‐wave power divider/combiners using waveguides. First, the perfect power combining condition is given when the divider/combiner is used as a single power combiner. From the numerical analysis based on the equivalent circuit, it is shown that a highly efficient power combining is possible over a very broad frequency range. It is shown also that the degradation of the combining efficiency with respect to the deviation of the input amplitudes and phases from the designed values is small.

For a power dividing‐combining system using two identical power divider/combiners, it is shown that a broadband characteristic can be obtained, the bandwidth increases with a number of branches, and the performance degradation by failure of one of the devices in the unit amplifiers can be kept minimum by appropriate choices of the device location. Further, the four‐ and six‐way power dividing‐combining experiment has been carried out at X‐band. The validity of the theory was confirmed. In the six‐way power dividing‐combining, a broadband characteristic was realized as evidenced by the bandwidth of 2.87 GHz with a combining efficiency of more than −0.5 dB and of 3.90 GHz with a return loss of less than −20 dB.
Analysis of operating mechanism in semiconductor optical modulator with electron‐depleting absorption control
Authors: Kuwamura Yuji , Yamada Minoru , Hashimoto Susumu
Published: July 2007

The optical absorption mechanism of a semiconductor optical modulator with electron‐depletion absorption control was theoretically and experimentally investigated. In the doped direct transition semiconductor material, optical absorption increased when electrons were depleted. In the region where electrons are depleted, the number of electrons in the conduction band and holes in the valence band decrease, the impurity energy level shifts due to the decrease of the screening effect and the internal electric field strength increases. Because of these phenomena, the band‐to‐band electron transition probability increases. As a result, the optical absorption increases in the modulator.
Dependence of plasma parameters on electric potential of electrode in microwave plasma
Authors: Kato Isamu , Matsushita Toru , Yamashita Makoto
Published: July 2007

The authors have been studying the double‐tubed coaxial line‐type microwave plasma chemical vapor deposition (MPCVD). The discharge tube of the present MPCVD is a dual‐tube structure made of a fused quartz outer discharge tube and stainless steel inner tube. The authors have discovered that the ion bombardment energy can be controlled without varying the electron densities and temperature by changing the potential of the substrate placed in a spatial after‐glow plasma. In the present research, it is found that the ion bombardment energy can also be controlled by changing the potential of the inner tube placed in the discharge plasma. However, the electron densities and temperature have exhibited a tendency different from the one when the substrate potential is varied. Hence, a theoretical calculation has been carried out on the electron densities and temperature based on Maxwell‐Boltzmann distribution. It is found that a different tendency can be explained from the fact that the electrons successively vanish on the deposition chamber wall from the higher‐energy side as the plasma spatial potential is reduced from about 13 V to 4 V so that the electron velocity distribution is modified.
Analysis method for light scattering from magnetic materials by the three‐dimensional boundary element method
Authors: Ogawa Masatsugu , Nakada Masafumi , Okada Mitsuya , Itoh Masaki
Published: July 2007

To analyze the light scattered from a magneto‐optical disk, a method is proposed for calculating the light scattered from a magnetic material with grooves. The model used is divided by an infinite boundary between the free space or an isotropic dielectric and an isotropic magnetic material. By using the relative permittivity of the isotropic magnetic materiel, the governing equation for the magnetic material is derived from Maxwell's equations. The three‐dimensional boundary element method is applied to this equation. The boundary element equation for free space or an isotropic dielectric material is the one in which the boundary element method is applied to a general Helmholtz equation. The one in the magnetic material is obtained by adding the volume integral in the magnetic material to the general equation. If boundary elements are large, the integral in the magnetic material near the boundary is evaluated at too small a value. The numerical results oscillate with only the foregoing method. To resolve this problem with taking practical memory size and computation time into consideration, an attenuating term is added to Green's function used in the integration in the magnetic material. With the method proposed, the optical scattering from a magnetic material can now be analyzed.
Barrier layerless submicron aluminum‐damascene interconnection using aluminum chemical vapor deposition with a new nucleation method
Authors: Shinzawa Tsutomu , Sugai Kazumi , Hayashi Yoshihiro , Nakajima Tsutomu , Kishida Shunji , Okabayashi Hidekazu , Tsunenari Kinji , Murao Yukinobu , Kobayashi Akiko , Yako Tadaaki
Published: July 2007

Barrier layerless submicron damascene interconnection has been realized by using a combination of novel aluminum chemical vapor deposition (AI‐CVD) and chemical mechanical polishing (CMP) techniques. A new nucleation method with tetrakis‐dimethyl‐amino titanium (TDMAT) gas pretreatment has enabled AI‐CVD to fill trenches without using a barrier layer which causes high resistivity. As a result, this technology achieved Al damascene interconnections with resistance as low as 600 ω/cm with half‐micron wide line and an aspect ratio of 3. This line resistance is one‐third of that for a conventional reactive ion‐etched Al line with an aspect ratio of 1.
Compensation for waveform distortion in a transmission fiber with loss by optical phase conjugation
Authors: Watanabe Shigeki , Shirasaki Masataka , Chikama Terumi
Published: July 2007

A new method is proposed to compensate for chromatic dispersion and self‐phase modulation in a transmission fiber with a loss using optical phase conjugate (OPC). The ratio of the optical Kerr effect and the dispersion was designed to be equal at each position before and after the OPC. The pulse shape is precompensated before OPC by transmission through a fiber with large dispersion whereas the transmission line consists of an optical amplifier repeated fiber link with a small dispersion. A computer simulation demonstrates effective compensation for waveform distortion in a 40‐Gb/s no‐return‐to‐zero (NRZ) intensity‐modulated light transmission. The method will be effectively applied to both wavelength demultiplexing method (WDM) systems and long‐haul transmission systems.
Scattering parameter estimation accuracy of root‐MUSIC algorithms in electromagnetic wave scattering measurements
Authors: Yamada Hiroyoshi , Yamamoto Kazuaki , Yamaguchi Yoshio , Sengoku Masakazu
Published: July 2007

An application of the superresolution method for the analysis of the electromagnetic scattering data is expected to be effective for experimental verification of the geometrical optics approximation theory and the analysis of multiple paths. There exist many techniques for the superresolution method. It is desirable to select an appropriate technique based upon the characteristics of the individual algorithms. Among these techniques, the Root‐MUSIC method has been proposed; this method enables treatment of the signal attenuating exponentially with respect to frequency. In the modified Root‐MUSIC method, arbitrary frequency characteristics can be treated.

This paper investigates the estimation accuracy of the scattering center and the attenuation coefficient when the Root‐MUSIC method and the modified Root‐MUSIC method are applied to the estimation of scattering. With the backscattering data of a conducting sphere, the estimation accuracy of the scattering parameters versus the signal‐to‐noise ratio (SNR) and the number of snapshots is investigated by computer simulation. As a result, it is found that the estimation accuracy of the modified Root‐MUSIC method is much better than that of the conventional Root‐MUSIC method in the case of a low SNR and a small number of snapshots. Experimental results are also reported.
Various equivalent circuits for thickness mode piezoelectric transducers
Authors: Chubachi Noriyoshi , Kamata Hiroshi
Published: July 2007

The equivalent transmission line model originally proposed by Nukiyama [5] and applied to the thickness mode piezoelectric transducers by Kikuchi et al. [6] is reviewed and its characteristics are described. The model is compared with those proposed by Mason [4] and by Krimholz et al. [2]. The equivalent transmission line model developed by Kikuchi et al. [6] was derived from the fundamental piezoelectric equation and Newton's equation of motion via the Laplace transformation. A new equivalent circuit in a time domain was derived as well. By comparing the equivalent circuit in a time domain with the equivalent transmission line model [6], it was demonstrated that the equivalent transmission line model is a fundamental equivalent circuit that is effective both for analyses in a time domain and for conventional analyses in a frequency domain. It is also demonstrated that, when the simultaneity between electric and acoustic signals is neglected, the equivalent circuits [2, 4] can be derived from the equivalent transmission line model.
Properties of phase‐conjugate reflectivity of self‐pumped four‐wave mixing
Authors: Dohata Masayoshi , Okamoto Atsushi , Enbutsu Koji , Sato Kunihiro
Published: July 2007

The properties of the phase‐conjugate reflectivity are analyzed anew for the self‐pumped four‐wave mixing in which only the two waves, i.e., the forward pump wave and the probe wave, are incident on the photo‐refractive crystal and the phase‐conjugate wave of the forward pump wave is used as the backward pump wave.

First, by means of a model in which a Cat‐type phase conjugator is placed outside the interaction region, the equation for the phase‐conjugate reflectivity of self‐pumped four‐wave mixing using a transmission grating is derived. Next, the numerical calculations have been used for the first time to determine the effects of the coupling strength, the probe ratio as the incident intensity ratio of the forward pump wave to the probe wave, and the reflectivity of the Cat‐type phase conjugator on the entire phase conjugate reflectivity. Since the equation describing the phase‐conjugate reflectivity has multiple solutions, the strict analysis of the equation shows that the phase‐conjugate reflectivity has multiple values. Further, the conditions for high phase‐conjugate reflectivity has been studied.
A finite‐element beam‐propagation method for strongly guiding optical waveguides with magnetooptic materials
Authors: Tsuji Yasuhide , Koshiba Masanori , Tanabe Tomohide
Published: July 2007

To the best of the knowledge of the authors, the formulation is carried out for the first time on the finite‐element beam‐propagation method for the analysis of the magnetooptic waveguide in which the structure varies along the propagation direction. The present method is applicable not only to the case in which refractive index difference is small but also to the case for the TE mode and the TM mode propagating in a waveguide with a large refractive index difference. To suppress the spurious reflection from the computational window edges, the transparent boundary condition is applied.
Piezoelectric vibratory gyroscope as an angular velocity sensor
Authors: Konno Masashi , Sugawara Sumio , Kudo Subaru
Published: July 2007

Guidelines are given for designing a piezoelectric vibratory gyroscope to be used as an angular velocity sensor. First, a basic equivalent circuit is given and an approximate equation is derived for sensitivity. Based on the equation, guidelines and issues related to improving sensitivity are discussed. The relationship between the output signal and difference in resonance frequencies of the driving and detecting sides is investigated for cases where the angular velocity is either constant or changing sinusoidally with time. The results are then used to determine the resonance frequencies. Furthermore, a design guideline based on an integral equivalent circuit, which has taken the effects of leakage output into consideration, is discussed and an approach is suggested for supporting the gyroscope. Finally, the performances of various gyroscopes are compared and the utility of a piezoelectric gyroscope as an angular velocity sensor is discussed.
Properties of zinc oxide films deposited by a radio‐frequency magnetron mode electron cyclotron resonance sputtering system
Authors: Kadota Michio , Minakata Makoto
Published: July 2007

We reported that zinc oxide (ZnO) films deposited by direct current (DC)‐mode electrocyclotron resonance (ECR) and radio frequency (RF)‐mode ECR sputtering systems had shown excellent piezoelectric properties and c‐axis orientations. The RF‐mode ECR sputtering system was capable of depositing ZnO films on glass substrates without evidence of column and fiber grains in cross‐section analysis while driving a 1.1‐GHz fundamental Rayleigh surface acoustic wave (SAW). In this paper, we investigate the properties of ZnO film deposited by an RF‐magnetron‐mode ECR sputtering system which has added magnets to the outside of a cylindrical zinc metal (Zn) target of the RF‐mode ECR sputtering system. The ZnO film on the glass substrate deposited by this system was capable of driving a 1.3‐GHz fundamental Rayleigh SAW. This shows a higher frequency than the previously reported ZnO film. This film exhibits most of the same effective electromechanical coupling factors (keff) as the theoretical keff values calculated by finite‐element method (FEM) using the constants of ZnO single crystal (that is, 97 percent of theoretical value) and 0.6 ∼ 3.6 dB lower insertion loss in comparison with the films deposited by the DC‐mode ECR and the RF‐mode ECR. A (1120) plane epitaxial ZnO film was deposited at low temperatures on an R‐plane sapphire substrate using this system and was capable of driving a 2.54‐GHz Sezawa wave. By measuring the photoluminescence property of a thin, 1.2‐μm, epitaxial ZnO film, free exitons are observed for the first time.
Use of multiple‐valued logic with 1.9‐V operational power supply to obtain a high‐speed current‐mode logic circuit
Authors: Sugimoto Yasuhiro
Published: July 2007

This paper proposes a new construction of bipolar current‐mode (CML) logic circuits based on the multiple‐valued logic concept. Applying the multiple‐valued logic concept, the new logic function, which can replace the conventional stack logic circuit and can be operated by a low supply voltage, can be realized. In conventional circuits, it is difficult to generate a signal with multiple voltage levels at the same time as the output of a logic gate and logic gates must be connected by placing a level‐shifter between them.

A circuit is devised in this study that generates the multiple‐valued logic levels (three levels in this paper) simultaneously at the output of the logic gate. Also, it is examined whether or not the basic logic functions, such as NAND, NOR, EX‐OR, and D‐Latch, can be realized by the proposed configuration. The characteristics of the proposed circuit are circuit simulated by a SPICE circuit simulator. It is seen as a result that the power consumption, the logic density, and the high‐speed performances, comparable to the conventional stacked‐gate logic circuit, can be realized with the low supply voltage of 1.9 V.
Operation of optical information retrieval system using spatial light modulator
Authors: Hatori Masaaki , Shioya Kouhei , Ohkawa Masashi , Sekine Seishi , Tsuchida Keiichi , Mita Motohito
Published: July 2007

Optical information retrieval systems based on Fourier optics and using holographic memories of high‐density recording capability, which raise the possibility of parallel information processing, have been proposed for a long time. However, the development of spatial light modulators which are the key devices in such systems has been delayed considerably and, so far, there is no report on optical information retrieval systems using spatial light modulators.

With this as background, a spatial light modulator (SLM) based on a large‐permittivity crystal is fabricated and its operation in a small‐size system is verified. First, based on the function of the spatial modulator, the hologram and the detection sections are designed and specifications of the system are decided. Next, the two different schemes of synchronous and direct detection methods are applied to the information retrieval of 18 bits consisting of nine pieces of holograms. As a result, it is understood that retrieval is possible using even the currently available spatial light modulators. The relation between the functions of the SLM and the system also is clarified. However, there are several problems in realization of such systems, a discussion of which is presented in this paper.
Preparation of CuTi‐Cu3Ti compound alloy films and their applications as diffusion barrier in Cu/CuTi‐Cu3Ti/TiN/Si multilayered contact system
Authors: Yoshimoto Ken‐Ichi , Sasaki Katsutaka , Yanagisawa Hideto , Noya Atsushi
Published: July 2007

The CuTi2 intermediate layer in a Cu/CuTi2/Ti/Si multilayered contact system disappears when heat‐treated at a temperature higher than 500°C. Thus, to improve the thermal stability of a Cu/CuTi2/Ti/Si multilayered contact system, it is necessary to replace the CuTi2 layer with other Cu‐Ti compounds that are thermally stable at temperatures higher than 500°C. Among various Cu‐Ti compounds, Cu3Ti is the most stable compound formed by heat‐treating the Cu/Ti bilayered system. However, since it is difficult to form a monolithic layer of Cu3Ti intermetallic compound, Cu‐Ti alloy systems which contain Cu3Ti and can be formed at relatively low temperature were investigated. The CuTi‐Cu3Ti compound alloy films were formed when the Cu/Ti bilayers were heat treated at 350°C for four hours. Thus, the thermal stability of a Cu/CuTi‐Cu3Ti/TiN/Si contact system was investigated. The experimental results indicate that the top layer of Cu can be preserved even when heated at 600°C and the interdiffusion between Cu and Si can be minimized.
Photolithography using half‐tone phase‐shifting mask
Authors: Hasegawa Norio , Imai Akira , Terasawa Tsuneo , Hayano Katsuya , Tanaka Toshihiko , Oki Yumiko , Murai Fumio
Published: July 2007

A half‐tone phase‐shifting mask (HPM) is effective in improving resolution and focus latitude of an isolated hole pattern. HPM can be fabricated by the conventional method and a practical phase‐shifting technique can be realized using HPM.

The authors developed a mask‐defect repair method and an opaque pattern formation technique which suppresses the peripheral exposure due to light leakage. The mask defect was repaired by blackening the defect. The formation of an opaque ring in the peripheral area of a main field was achieved by placing patterns with dimensions smaller than the resolution limit. In addition, it was found by both simulation and experiment that the focus latitude could be expanded by placing additional patterns at proper locations and by illumination of highly coherent light.
Fixed pattern noise of amplified MOS imager in scaling down
Authors: Andoh Fumihiko , Tanaka Katsu , Kawashima Hiroshi , Yamawaki Masao
Published: July 2007

Amplified MOS imagers (AMIs) have random noise figures comparable with those of charge‐coupled devices (CCDs) but suffer from significant fixed pattern noise (FPN). AMIs are now being experimentally scaled down to a size of 250, 000 pixels per quarter inch for possible use in Hi‐Vision systems. We fabricated test devices in order to determine which elements make the greatest contribution to FPN after scaling down. The amplification transistors and reset transistors proved to make comparable contributions to FPN and, in addition, exhibited similar gate‐length fluctuations (rms value about 21 nm). Fluctuations in the gate lengths of other components of the devices produced no significant effect on FPN. In the amplification transistors, variations in the voltage threshold produced four times as great an effect on FPN as variations in the gain factor. On exposure to light, FPN increased with aperture.
Diffusion barrier effects of Al3Zr/Zr bilayered films interposed between Al and Si
Authors: Yanagisawa Hideto , Noya Atsushi , Sasaki Katsutaka , Abe Yoshio
Published: July 2007

The interfacial solid‐phase reactions taking place in the Al/Al3Zr/Zr/Si contact systems have been investigated to evaluate the effectiveness of Al3Zr/Zr bilayered films as a diffusion barrier in Al‐metallization technology. The interposition of an intermediate Al3Zr layer can successfully suppress the possible spontaneous rections between the Al and Zr layers because nearly‐minimum free energy states are realized at interfaces of both Al/Al3Zr and Al3Zr/Zr. It is revealed that the present system tolerates heat treatment at temperatures of up to 470°C and the formation of a Zr‐silicide layer is observed at the Zr/Si interface after heat treatment in the temperature range of 450 ∼ 470°C.
Memory macrocell techniques for 1‐V battery‐operated ASICs
Authors: Shibata Nobutaro , Date Shigeru
Published: July 2007

Low‐power ASICs with a single Ni‐Cd battery cell are necessary to implement small, lightweight.and economical portable equipment. This paper describes SRAM and mask‐ROM macrocell techniques for 1‐V battery‐operated ASICs. Synchronous specification combined with pipeline technique is employed to enhance the performance of maximum operating frequency.

Six‐transistor CMOS SRAM cells are realized by using high threshold‐voltage (VTH) MOSFETs to reduce the power dissipation due to the subthreshold leakage current. Peripheral circuitry is designed with multi‐threshold‐voltage CMOS (MTCMOS) technology, which is implemented by using high‐ and low‐VTHMOSFETs. A test chip including several memory macrocells is fabricated with 0.5‐μm MTCMOS technology, and the macrocell demonstrated 30‐MHz operation at a 1‐V power supply.
Development of a liquid crystal photo fabrication system
Authors: Kimura Masayuki , Kubota Etsuo , Bessho Nobuo , Fukuda Ichiro
Published: July 2007

Reduction of fabrication and operational costs has become an important issue in today's laser scanning photo‐fabrication system. In this paper, a novel liquid crystal‐type photo‐fabrication system (LC‐PFS) that does hot require a laser will be proposed. It will be shown that this system is useful for three‐dimensional visualization of CAD and CT image data.

In this study, the design indices for a double‐layered STN (DSTN) liquid crystal panel for electrically rewriting exposure mask were fust clarified by numerical analysis. Then the optimum design condition for the liquid crystal panel that maximizes the contrast ratio (hardening sensitivity corrected contrast) was experimentally obtained. Finally, a liquid crystal panel with a diagonal dimension of 11.4 inches and 1.9 × 105 pixels was fabricated. Using LC‐PFS test equipment with the forementioned panel, a real‐sized skeleton was created to demonstrate the advantage of this system.
Deep‐submicron CMOS technologies for low‐power and high‐performance operation
Authors: Deura Manabu , Nara Yasuo , Yamazaki Tatsuya , Gotoh Kenichi , Ohtake Fumio , Kurata Hajime , Sugii Toshihiro
Published: July 2007

Integrated circuits with 1GHz logic, 1G bit DRAM, and 1G transistors, together with the CMOS technology with a gate length of less than 0.2 μm are the ingredients of the “Giga‐Era.” However, in order to integrate these billions of MOSs at giga‐frequencies, the problem of the power consumption cannot be avoided. It is a common practice to cope with this problem by reducing the power supply voltage. In deep submicron MOS, although the basic gate delay is not likely to degrade as the power supply voltage is reduced, it is necessary to set a low threshold value (Vth) within the wafer plane with reduced parasitic devices, if the absolute current values become important, as in the interconnect load. However, reliability problems involving the short‐channel effect and hot carriers then cannot be avoided. This paper describes the use of the cobalt silicide process and shallow extension structure of the source/drain to reduce the parasitic resistance. It is also shown that setting a low Vth with fewer fluctuations is possible by combining the double‐side‐wall process and the counter‐dose process. By means of the above process, deep submi‐cron CMOS with low parasitic resistance and low Vth can be fabricated.
Alleviation of subthreshold swing and short‐channel effect in buried‐channel MOSFETs: The counter‐doped surface‐channel MOSFET structure
Authors: Enda Toshiyuki , Shigyo Naoyuki
Published: July 2007

One of the important issues for the realization of deep, submicrometer CMOS is the choice between a buried channel or a surface channel for pMOS. Conventionally, buried‐channel devices have been considered difficult to miniaturize and operate at low voltage. This is because they have a distinct short‐channel effect and a large S‐swing (subthreshold swing). However, the conventional analysis considers only the case in which the buried layer is deep. The junction depth is reduced on miniaturization, but there has not been sufficient analysis for the case of a shallow buried layer. Therefore, we have analyzed by simulation the way in which the buried‐channel S‐swing and short‐channel effect depend on the depth of the buried layer and the source/drain junctions. We have found that if the buried layer is shallow enough for complete depletion, the S‐swing becomes smaller than that for a surface channel and the subthreshold characteristics become sharper. In other words, we have shown for the first time that the optimized structure for a minimum S‐swing is not a surface channel but a buried channel. This structure is called CDSC (counter‐doped surface‐channel). It is also demonstrated that the short‐channel effect can be suppressed better than in a surface channel if the source/drain is shallower than the buried layer. Therefore, CDSC is promising for deep, sub‐micrometer pMOS.
Reasons for heat resistance and reduced oxide thickness of Ta2N anodized capacitors
Authors: Yamane Misao , Sasaki Katsutaka , Abe Yoshio , Kawamura Midori , Noya Atsushi
Published: July 2007

Ta2N anodized capacitors have much greater heat resistance than Ta anodized capacitors. The difference between the heat resistances of the Ta and Ta2N capacitors was investigated by Auger analysis and it was found that the Ta2N compound thin film itself has a high heat resistance: Very little thermal oxidation of this film occurs until relatively high temperatures. The thermal degradation of TaN2 anodized capacitors which takes place at temperatures above 450°C was found to be due to the oxygen diffusion from the anodized layer to the Ta2N underlayer. Another cause of thermal degradation was the oxidation of the Al electrode at high temperatures. Therefore, both the breakdown of the interface between the electrode and anodized layer and the oxidation of Al also contributed to the thermal degradation of the capacitors at high temperature. Even though the thickness of the Ta2N anodized layer was reduced by using a 30 V anodizing voltage, the heat resistance was greater and the capacitance was 3 times as high as that of Ta capacitors anodized at 160 V.
Efficiency improvement by frequency modulation of carrier signal for an inductor commutation soft‐switched PWM inverter
Authors: Nagao Michihiko , Watanabe Shinichirou , Harada Koosuke
Published: July 2007

The inductor communication soft switched PWM inverter (ICSI) gives good output waveforms and allows high carrier frequencies. However, to realize soft switching, a circulating current must always flow, so that the efficiency is not as good as in the conventional hard‐switched PWM inverter (CHSI).

In this paper, to alleviate the efficiency deterioration due to the circulating current, we propose a technique which uses frequency modulation (FM) of the carrier signal. The frequency is designed to be higher at zero of the input signal and lower at its peak. By this technique, the circulating current is suppressed efficiently without sensing of the voltage and current of the main circuit, and efficiency is greatly improved. We quantitatively investigate this FM method and analyze the loss and efficiency of ICSI based on the FM method (FM‐ICSI). We also compare it with ICSI without the FM method and discuss the effectiveness of the FM method.
Propagation characteristics of microstrip line with semiconductor substrate under laser spot illumination
Authors: Horii Yasushi , Tsutsumi Makoto
Published: July 2007

In this paper, the scattering characteristics of an optically controlled microstrip gap fabricated on a silicon substrate are analyzed theoretically using the (FD)2TD method, and the effects of the spot diameter of the laser beam, the location of illumination, and the plasma thickness on such characteristics are studied. The theoretical results show that twin peaks can be observed in the transmission coefficient (S21) by the use of a laser beam with a spot diameter smaller than the gap, and that nondispersive characteristics can be developed by a laser beam having a large spot diameter. Finally, the theoretical results are compared with measurements.
The BETA‐MOSFET: A novel high‐performance transistor
Authors: Yoh Kanji , Koizumi Ryouji , Hashimoto Naotaka , Ikeda Shuji
Published: July 2007

The bipolar enhanced transistor action (BETA)‐MOSFET, operating in a mixture of FET mode and bipolar mode, has been fabricated. Unlike the lateral bipolar transistor, its base current can be automatically controlled by the gate voltage. Hence, the device operating voltage can be in a wide range and is a maximum of −4 V. It is confirmed that the device can be treated as a high‐performance MOS‐FET in circuit analysis. Three types of device structures, with a gate‐substrate contact that includes an ultrathin‐film tunnel junction, are fabricated and evaluated. In the p‐channel BETA‐MOSFET, the drain current and the maximum transconductance are about four times those of the conventional MOSFET while maintaining the same threshold voltage. This result implies that the BETA‐MOSFET with a gate length of 1.3 μm exhibits a superior performance equivalent to a 0.1‐μm p‐MOSFET.
Boundary management in action reflection learning™ research: Taking the role of a sophisticated barbarian
Authors: Yorks Lyle , O'Neil Judy , Marsich Victoria J. , Nilson Glenn E. , Kolodny Robert
Published: July 2007

Boundary management is a challenge in all forms of participant observation. Here the authors explore considerations that they believe are unique to participant observation research within Action Reflection Learning™ (ARL™) programs. The authors hypothesize that field researchers' efforts to manage boundaries bear some similarities to a key phenomenon of the program itself, that is, learning takes place as a result of reflection informed by an outsider's perspective. The researcher's role is given the label of sophisticated barbarian because researchers have some specialized knowledge and can thus ask some sophisticated questions. Yet, because they maintain some distance from the existing group's culture and mindset, they may ask some questions that seem barbaric to insiders.
Systematic agreement: A theory of organizational alignment
Authors: Semler Steven W
Published: July 2007

Organizational alignment is a concept often mentioned in human resource development (HRD) models but rarely explained in detail. This theory of alignment looks at the extent to which strategy, structure, and culture create an environment that facilitates the achievement of organizational goals. The concept of alignment lends itself to the creation of high‐performance work systems by explaining how the interdependent elements of the organization can achieve greater individual and collective efficiency and effectiveness. Well‐aligned organizations apply effective leadership and HRD processes to create systematic agreement among strategic goals, tactical behaviors, performance and reward systems, and the organizational culture. This agreement helps people to remove barriers to cooperation and performance and thereby increases the performance of individuals, processes, and the organization as a whole.
Toward construct validation of a transfer climate instrument
Authors: Holton Elwood F. , Bates Reid A. , Seyler Dian L. , Carvalho Manuel B.
Published: July 2007

Despite general acknowledgment of the difficulty in transferring learning, no validated and generally accepted instrument exists to measure factors believed to affect its transfer. Rouiller and Goldstein (1993) developed an eight‐factor structure for a transfer climate instrument but could not validate the structure because their sample size was inadequate. This study attempted to validate their hypothesized constructs using factor analysis and found a substantially different factor structure, suggesting a different direction for future transfer climate instrument research. The results suggest that trainees perceive climate according to referents in the organization rather than according to psychological cues, as Rouiller and Goldstein proposed. Consequently, a transfer climate instrument incorporating additional constructs was analyzed. The resulting nine‐factor solution suggested additional constructs and indicated that transfer climate was perceived according to organizational referents.
Ratee preferences concerning performance management and appraisal
Authors: Gosselin Alain , Werner Jon M. , Hallé Nicole
Published: July 2007

A diverse sample of 265 employees was surveyed for ratee preferences concerning seven performance management and appraisal issues. Research questions were formulated on appraisal source, feedback issues, and the performance management process. Results indicated that subjects most trusted their immediate supervisor as an accurate source for their appraisal and that they preferred having prior knowledge of their supervisor's expectations, receiving ongoing informal feedback throughout the appraisal period, and receiving formal appraisals at least twice a year. Subjects expressed preferences for developmentally oriented appraisals that were based mostly on the results of work. Preferences were not moderated by ratee experience or gender. Implications for human resource development professionals are discussed.
Environmental factors and the effectiveness of workforce diversity training
Authors: Hanover Jeanne M. B. , Cellar Douglas F.
Published: July 2007

This study examined the effects of a diversity training workshop on self‐perceptions of behavior and importance of related management practices among ninety‐nine middle managers in a large corporation. It also examined relationships between environmental variables and training criterion variables. It was hypothesized that the workshop would positively affect perceptions of behavior and ratings of importance and that the work and social environments would influence the training outcomes. Analyses were conducted to determine if the environmental variables had direct or indirect effects on the training criterion variables. The study found that those who attended the workshop did rate management practices related to diversity as more important and did perceive themselves as engaging in such practices more than did a control group. The social environment variable indirectly affected posttest importance ratings of diversity‐related management practices and self‐perceptions of behavior through its effect on initial levels of those variables, but the work environment measure was not related to the criterion variables.
Informal learning in corporate workplaces
Authors: Garrick John
Published: July 2007

This article examines the informal learning of two principal HRD practitioners working at the Sydney 2000 Olympic Games construction sites, highlighting tensions between individual experience and the workplace. The article is based on an interpretive study in which findings are “counterpointed” by postmodern and critical perspectives. Key questions include these: Why is informal learning, at this particular moment, an important research focus in HRD? What are the problems of defining informal learning? How does one learn informally, and what affects it? The article concludes by rethinking informal learning and discussing implications for future HRD research and practice.
Leadership styles and management practices of russian entrepreneurs: Implications for transferability of western HRD interventions
Authors: Ardichvili Alexander , Cardozo Richard N. , Gasparishvili Alexander
Published: July 2007

This study explores the degree of readiness among Russian entrepreneurs to adopt Western HRD interventions. Structured interviews were conducted with 256 owners and CEOs of private Russian companies created after 1986 as independent start‐ups or as spinoffs from state‐owned firms. Manufacturing, retail, wholesale trade, and service sectors were represented. Entrepreneurs from the eight largest Russian cities were selected to represent the major economic regions. The study examined leadership styles, management decision‐making processes, and the degree of involvement in management and HRD interventions. Among other results, it found that work design and performance management interventions were used more often than employee training and development or interventions aimed at changing the organizational culture.
Learning network theory: The tension between learning systems and work systems in organizations
Authors: van der Krogt Ferd J.
Published: July 2007

This article presents a theory on the organization and development of learning systems—the learning network theory. In this theory, learning systems in work organizations are analyzed in a network approach to organizations. Learning systems are subject to tensions, which arise from their dual orientation: an orientation toward the development of human potential (humanity) and an orientation toward the development of the work process (work relevance). Learning network theory offers a frame of reference for analyzing the tensions between humanity and work relevance and provides leads for handling such tensions. The article concludes with a number of suggestions for further research into the organization of learning systems.
An extension of the theory of margin: A framework for assessing readiness for change
Authors: Hanpachern Chutima , Morgan George A. , Griego Orlando V.
Published: July 2007

The study investigated the relationships of margin in life (MIL) and demographic variables to readiness for change. Results, based on 131 employees of a manufacturing company, showed that overall MIL and five work subscales had significant positive relationships with readiness for change. The demographic variables of department, position, and length of employment were also related to readiness for change but not to MIL. Three variables combined to predict readiness: employees who get more personal power than burden from their relations with managers, employees who themselves are in managerial positions, and employees who are relatively new to the company. Among the MIL subscales, all of the work aspects, except social relations in the workplace, had higher ratings on load than on power, whereas the reverse was true for the nonwork aspects of family, self, and health. The results suggest strategies to facilitate effective change interventions.
Influence behaviors and managerial effectiveness in lateral relations
Authors: Church Allan H. , Waclawski Janine
Published: July 2007

This article reports on a study of the influence practices and effectiveness of 207 middle‐level staff and program management personnel in nonmanagerial positions in a high‐tech government agency in the United States. Multiple regression results were used to identify specific influence behaviors practiced in lateral relations with peers that directly affected supervisors' perceptions of effectiveness. As hypothesized, managerial self‐awareness (operationalized as congruence in self‐peer ratings) was found to contribute significantly to relationship management aspects of individual effectiveness. Implications of these results for team‐based work in organizations as well as OD and HRD initiatives are discussed.
Understanding support for innovation in a large‐scale change effort: The manager‐as‐instructor approach
Authors: Watkins Karen E. , Ellinger Andrea D. , Valentine Thomas
Published: July 2007

A large‐scale organizational innovation, a cascaded training delivery strategy, at a Fortune 10 automotive manufacturer was studied to evaluate its overall impact and to determine possible predictors of support for the innovation. Findings from this innovation study inform a model of innovation implementation and suggest guidelines for using mangagers as instructors.
Leadership and culture: Work‐related values and leadership styles among one company's U.S. and German telecommunication employees
Authors: Kuchinke K. Peter
Published: July 2007

This survey‐based study examines differences in leadership styles and work‐related values among managers, engineers, and production employees of one company's U.S. and German telecommunication employees. Using Bass and Avolio's Full‐Range Leadership theory and Hofstede's theory of culture, the results reveal lower levels of transformational leadership styles among German employees, but no differences in leadership styles among different job categories in either country. There were country‐level differences in culture that explained a portion of the variance in leadership scores. Job category also had a main effect on cultural values. The study points to patterns of work‐related values different from those predicted in earlier research, and to the need for further refinement of research in leadership theory and our understanding of culture.
Validity of multiple ratings of business student performance in a management simulation
Authors: McEnery Jean M. , Blanchard P. Nick
Published: July 2007

This study examined the reliability and validity of assessor, peer, and self‐ratings of management skills. The sample was made up of 261 undergraduate business students at a large midwestern university. An assessment center process was used to examine the skills of students in a management skills course using the Looking Glass simulation. Assessors were graduate students and faculty. This study found a lack of convergent and divergent validity in assessor‐peer ratings and assessor–self‐ratings. However, convergent and divergent validity were found in self‐peer ratings. The conclusion is that peer and self‐ratings may be very useful sources for developmental information under conditions of rater anonymity and when organizational rewards are not at stake.
Bridging Gaps: An update from the ASTD research committee
Authors: Dilworth Robert L. , Redding John
Published: July 2007

Annually, the American Society for Training and Development (ASTD) Research Committee is invited to use this editorial space to provide an update regarding the committee's directions and activities. So what is the committee up to? Here is the short answer. We are seeking to bridge two gaps: the gap between practitioners and researchers and the gap between practitioners and senior executives.

In last year's editorial, Laurie Bassi, ASTD's vice president for research, made a compelling case that the gap between practitioners and researchers is widening (Bassi, 1998). According to Bassi, practitioners are being bombarded with new HRD (human resource development) dilemmas at accelerating rates of speed. Yet the means to create and disseminate research‐based solutions to these dilemmas remain unchanged. They tend to be slow, cumbersome, and difficult for practitioners to access. The committee has several initiatives under way that are aimed at addressing the practitioner‐researcher gap:
Implications of leader‐member exchange theory and research for human resource development research
Authors: Burns Janet Z. , Otte Fred L.
Published: July 2007

Leader‐member exchange (LMX) theory and research is one approach to studying organizational leadership. It has developed as an alternative to average leadership style (ALS), which attempts to identify a single most effective leadership style. LMX focuses instead on the heterogeneity of dyadic relationships. LMX theory is not yet well enough developed to be a guide to HRD practitioners, but further research in this area could lead to the development of better theory to guide HRD interventions. There are some strengths and many weaknesses in LMX theory and research. Recent research has supported the theory, but research is needed on instrumentation, the impact of LMX quality on organizational outcomes, the ways in which leader‐member relationships develop, and behavioral components affecting the initiation of leader‐member relationships.
Integrating learning with working: A reconception of the role of workplace learning
Authors: Torraco Richard J.
Published: July 2007

The nature of work continues to evolve from predictable, deterministic patterns to forms that are more contingent and idiosyncratic. The evolution of work and of the expertise needed to perform it have not been accompanied by innovations in the models used by workplace educators to develop this expertise. For some technical work roles, present models are inadequate for developing the skilled performance the roles require. Using in‐depth accounts of actual work activity, this article examines changes in how work is accomplished. Emergent themes from selected work settings are analyzed against present models of employee development. Using the theories of situated learning and distributed cognition, a reconception of the role of learning interventions is proposed that more fully integrates learning with working.