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In this paper, we present a state-of-the-art integrated GaN power IC capable of operating in a high frequency (MHz) regime. This realizes system size reduction, 60% maximum, of a power IC. The IC consists of two output power transistors (PT) and two gate drivers (GD). The key devices in the IC are normally-off gate injection transistors (GITs) for PT and GD and a normally-on hetero-junction field effect transistor (HFET) for GD. Novel local control of carrier concentration of an identical 2 dimensional electron gas (2DEG) at an AlGaN/GaN interface which made integration of the transistors with such a large threshold voltage difference possible is described. A specially developed post-passivation interconnection process giving low parasitic components is also described. The IC applied to a 12V–1.8V DC-DC converter shows high frequency switching operation well beyond the limit of Si pointing to future improvement in consumer electronics power supply systems.

Summary Bone-marrow-derived macrophages are divided into two phenotypically and functionally distinct subsets, M1 and M2 macrophages. Recently, it was shown that adoptive transfer of M2-polarized peritoneal macrophages reduced the severity of experimental colitis in mice. However, it is still unclear whether peritoneal macrophages possess the same ability to be polarized to cells with functionally different phenotypes and cytokine production patterns as bone-marrow-derived macrophages. To address this question, we examined the ability of peritoneal macrophages to be polarized to the M1 and M2 phenotypes and determined the specific cytokine profiles of cells with each phenotype. We showed that peritoneal macrophages, as well as bone-marrow-derived macrophages, were differentiated into M1 and M2 phenotypes following stimulation with interferon-γ (IFN-γ) and interleukin-4 (IL-4)/IL-13, respectively. Following in vitro stimulation with lipopolysaccharide, M2-polarized peritoneal macrophages predominantly expressed T helper type 2 (Th2) cytokines and regulatory cytokines, including IL-4, IL-13, transforming growth factor-β and IL-10, whereas M1-polarized peritoneal macrophages expressed negligible amounts of Th1 and pro-inflammatory cytokines. ELISA showed that M2-polarized peritoneal macrophages produced significantly more IL-10 than M1-polarized peritoneal macrophages. Notably, M2-polarized peritoneal macrophages contributed more to the suppression of T-cell proliferation than did M1-polarized peritoneal macrophages. The mRNA expression of Th2 cytokines, including IL-4 and IL-13, increased in T-cells co-cultured with M2-polarized macrophages. Hence, our findings showed that M2 polarization of peritoneal macrophages induced regulatory cytokine production and suppressed T-cell proliferation in vitro, and that resident peritoneal macrophages could be used as a new adoptive transfer therapy for autoimmune/inflammatory diseases after polarization to the regulatory phenotype ex vivo.

Biaxially oriented polypropylene (BOPP) films are used in a variety of areas around the world. They are especially well suited for food packaging and industrial usages because of their high productivity. Many studies on the stretchability with regard to crystal structure changes have been reported by various researchers because the machine speed has been increasing and the demand to produce thinner films has been becoming more important. Furthermore, a number of studies on the surface structure of BOPP films with craterlike roughnesses have been reported since the 1980s. Although a craterlike surface roughness was formed under specific film process conditions, the formation mechanism and the controlling method of the craterlike film surface are yet to be clarified. In this report, we demonstrated a new hypothesis for the craterlike film surface roughness formation mechanism by analyzing the morphology of the surface layer of polypropylene (PP) sheets and by investigating the relationship between the surface structural changes and the changes in the entire structure. As a result, we found that an overcritical crystallization time was needed to form the crater on the surface of the BOPP film, and the crater formation mechanism was closely related not only to the surface structure changes but also to the deformation phenomenon of the spherulite in the PP sheet during stretching. Furthermore, this report shows the controlling factors in the formation of the crater structure from the viewpoint of the production conditions. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012 Copyright © 2012 Wiley Periodicals, Inc.

Human homogamy may be caused in part by individuals' preference for phenotypic similarities. Two types of preference can result in homogamy: individuals may prefer someone who is similar to themselves (self-referent phenotype matching) or to their parents (a sexual-imprinting-like mechanism). In order to examine these possibilities, we compare faces of couples and their family members in two ways. First, "perceived" similarity between a pair of faces is quantified as similarity ratings given to the pair. Second, "physical" similarity between two groups of faces is evaluated on the basis of correlations in principal component scores generated from facial measurements. Our results demonstrate a tendency to homogamy in facial characteristics and suggest that the tendency is due primarily to self-referent phenotype matching. Nevertheless, the presence of a sexual-imprinting-like effect is also partially indicated: whether individuals are involved in facial homogamy may be affected by their relationship with their parents during childhood.

Biaxially oriented polypropylene films are widely used for food packaging and industrial films. Recently, machine speed has been increasing in order to obtain higher production rate, and film thickness has become thinner to reduce the environmental load. The customers' requirements for better production ability and thinner films have been becoming more demanding, but their demands are not always met because of lack of film stretchability in the final product. To meet the demands, research on stretchability has been conducted with the goal of finding the optimum polypropylene molecular structure for developing a new product by analyzing stretching force–strain data using a table tenter, which was thought to be the parameter of stretchability. It was found that low crystallinity and wide molecular weight distribution were effective in improving the stretchability from the table tenter test. By running the test with a sequential and biaxially oriented stretching machine, it was verified that samples produced by the above designed polymer indicated good thickness uniformity, which was considered to be the barometer of stretchability. Furthermore, it was concluded that analyzing the stretching force–strain data obtained from a table tenter is a good method to predict machine speed and film thickness. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers

The objective of this study is the presentation of an analytical method to support health consultants, thereby establishing an analytical method that enables them to select subjects for health guidance using health checkup data and to derive a suitable guidance policy for each subject. This paper examines an analysis method that maps a health checkup using Multi-Dimensional Scaling (MDS). MDS mapping of multivariate health checkup data for a health checkup examinee on a two-dimensional plane facilitates comprehension of a subject’s health condition easily as visual information. This study focuses on the efficacy of visualization from the viewpoint of supporting health consultants. The mode of display by MDS facilitates visual confirmation that groups outside of the scope of health guidance and at high risk are shown in a contrastive position. In addition, a medium risk group was plotted into an in-between position. A plot ofmore detailed classification for all inspection items suggests by concurrence an increased risk. Results of this study indicate that its coordinates are effective both in determining a subject’s health condition intuitively and in use as one index of risk formetabolic syndrome. These results are therefore considered useful for formulating health guidance plans such as priority issues.

Biaxially oriented polypropylene (BOPP) film accounts for a large amount of polypropylene since it is well suited for food packaging films or industrial films, because of its high performance in terms of mechanical and optical properties. Recently machine speed has been increasing to obtain higher production rate and film thickness has become thinner to reduce the environmental load. To meet the demands, many researchers have been investigating stretchability of PP by connecting the stretching force at the yield point and crystalline structure. Many other studies have been conducted regarding the surface structure of BOPP. Although there were some cases that crater-like film surface roughness was formed on BOPP films, the formation mechanism of craters has not been clarified. In this report, new hypothesis of the crater-like film surface roughness formation mechanism is proposed by observing the transformation of crater from sheet to BOPP film and by investigating the relationship between the stress–strain curve and surface roughness change. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

We carried out a retrospective questionnaire survey of 792 submucosal colorectal carcinoma (CRC) cases from 15 institutions affiliated with the Colorectal Endoscopic Resection Standardization Implementation Working Group in Japanese Society for Cancer of the Colon and Rectum. In these cases, endoscopic resection (ER) and surveillance was carried out without additional surgical resection. Local recurrence or metastasis was observed in 18 cases. Local submucosal recurrence was observed in 11 cases, and metastatic recurrence was observed in 13 cases. Among the 15 cases in which the depth of submucosal invasion was measured, two cases showed depth less than 1000 µm, which has other risk factors for metastasis. Metastatic recurrence was observed in the lung, liver, lymph node, bone, adrenal glands, and the brain; in some cases, metastatic recurrence was observed in multiple organs. Death due to primary disease was observed in six cases. The average interval between ER and recurrence was 19.7 ± 9.2 months. In 16 cases, recurrence was observed within 3 years after ER. Thus, validity of ER without additional surgical resection for cases with the conditions that the depth of submucosal invasion is less than 1000 µm and the histological grade is well or moderately differentiated adenocarcinoma with no lymphatic and venous involvement was proven.

Adsorptive granulomonocytapheresis (GMA) with the Adacolumn has been introduced as a non-pharmacologic treatment for ulcerative colitis (UC). However, a subset of patients who might respond well to GMA needs to be targeted. This study was conducted at three IBD centers to determine factors affecting the efficacy of GMA in patients with moderately-to-severely active UC.From January 2008 to December 2017, a total of 894 active episodes (first attack or relapse) in 593 patients were treated with GMA. Clinical remission was defined as normal stool frequency and no rectal bleeding. Multiple clinical and laboratory parameters at entry were considered for efficacy assessment.Clinical remission was achieved during 422 (47%) of the 894 treatment cases. In the multivariate analysis, predictors for favorable response to GMA were age ≤60 years, UC duration1 year, Mayo endoscopic subscore 2 (vs. 3), steroid naïve UC, and biologic naïve UC. Clinical remission rate was 70% in patients with four of the five factors, 52% in patients with three factors, 46% in patients with two factors, 39% in patients with one factor, and 18% in patients with none of these factors. Overall, the clinical remission rate was significantly higher in patients with a greater number of the five predictors (P 0.0001).GMA appeared to be effective in steroid naïve and biologic naïve patients with short duration of UC. Elderly patients (60 years) and those with severe endoscopic activity did not respond well to GMA. Additional, well designed, prospective, controlled trials should strengthen our findings.

Bleeding, perforation, and residual/local recurrence are the main complications associated with colonoscopic treatment of colorectal tumor. However, current status regarding the average incidence of these complications in Japan is not available. We conducted a questionnaire survey, prepared by the Colorectal Endoscopic Resection Standardization Implementation Working Group, Japanese Society for Cancer of the Colon and Rectum (JSCCR), to clarify the incidence of postoperative bleeding, perforation, and residual/local recurrence associated with colonoscopic treatment. The total incidence of postoperative bleeding was 1.2% and the incidence was 0.26% with hot biopsy, 1.3% with polypectomy, 1.4% with endoscopic mucosal resection (EMR), and 1.7% with endoscopic submucosal dissection (ESD). The total incidence of perforation was 0.74% (0.01% with the hot biopsy, 0.17% with polypectomy, 0.91% with EMR, and 3.3% with ESD). The total incidence of residual/local recurrence was 0.73% (0.007% with hot biopsy, 0.34% with polypectomy, 1.4% with EMR, and 2.3% with ESD). Colonoscopic examination was used as a surveillance method for detecting residual/local recurrence in all hospitals. The surveillance period differed among the hospitals; however, most of the hospitals reported a surveillance period of 3-6 months with mainly transabdominal ultrasonography and computed tomography in combination with the colonoscopic examination.

A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis.

Voice activity detection (VAD) plays an important role in speech processing including speech recognition, speech enhancement, and speech coding under noisy environments. We have developed an evaluation framework for VAD under noisy environments, named CENSREC-1-C. We designed this framework for simple isolated utterance detection and hence, this framework consists of noisy continuous digit utterances and evaluation tools for VAD results. We define two evaluation measures, one for frame-level detection performance and the other for utterance-level detection performance. We also provide the evaluation results of a power-based VAD method as a reference.

We study the possibility of testing local realistic theory (LRT) based on the Bell inequality for the correlations in the decay modes of entangled K or B-mesons. It is shown that such a test is possible for a restricted class of LRT, despite the passive nature of decay events and/or the non-unitary treatment of the correlations which invalidate the test for general LRT. Unfortunately, the present setup of the KEKB (Belle) experiment, where the coherence of entangled B-mesons has been confirmed recently, does not admit such a test due to the indeterminacy in the separate decay times of the entangled pairs.

Unique deterioration with a striped pattern caused by thermal heating is reported for injection molding comprising polypropylene/ethylene–α-olefin rubber blends. This stripe is due to the formation of glossy and cloudy parts in alternation approximately perpendicular to the flow direction of the molten resin. On the surface of the cloudy part, a number of micro-objects appear. They have a dome shape about 10 μm in diameter and 2 μm height. Some experimental evidence indicates that the objects are composed of the rubber contained in the blends. On the other hand, only a few objects appear in the glossy region after heating. This is the reason that the stripe with the micro-objects (migrating rubber to the surface) is examined in terms of a higher order structure of injection molding with laser scanning microscopy, wide-angle X-ray scattering, and microhardness (Martens hardness). Consequently, we have concluded that this thermally deteriorated stripe depends on periodic changes in the crystallinity along the flow direction. The evidence indicates that a snakelike flow occurs during the injection process of the molding. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008

金沢大学大学院自然科学研究科, 出光興産㈱ 先進技術研究所 解析技術センター 第二解析技術室, Many additives are commercially used to add more favorable qualities to films. The bleeding process by which the additive in a film comes to the surface is considered. A new bleeding model of additives in a polypropylene film under atmospheric pressure was investigated. Solubility and diffusion are found to be important for explaining this bleeding process. It was found that the experimental results were explained more precisely by assuming a twostep transport process between the crystalline regions and the amorphous ones. The solubilities and diffusion coefficients of UV-stabilizers such as 2-(2H-benzotriazol-2-yl)-4(l,l,3,3-tetramethylbutyl)phenol and 2-(2H-benzotriazol-2yl)-4-methylphenol were determined at 4O°C. The difference between the saturation solubilities and the diffusion coefficients of UV-stabilizers was discussed by comparing with the results of molecular dynamics (MD) simulation. © 2007 Wiley Periodicals, Inc.

Unique deterioration with a periodical striped pattern on the injection moldings of polypropylene/rubber blends is reported. After exposure to ultraviolet irradiation with a sunshine fade meter, striped patterns appeared on the injection moldings along the flow direction of the molten resin during the filling process of injection molding, even though the initial specimen showed no sign of any stripe pattern on its surface. The stripe was carefully observed with ultrasonic echo imaging, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. As a result, a number of microvoids were observed inside the injected body at a depth of 50–100 μm from the surface. It became clear that the difference in the number of voids along the flow direction formed the stripe pattern. Surprisingly, these voids occurred in domains comprising a rubber phase. The distribution of voids in depth indicated the existence of a trace of a snakelike flow caused inside the injected body during the injection-molding process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

The parametric study using FEM and the experiment of T-beams prestressed with external tendons have been performed to investigate the factors thought to influence on the shear mechanism of externally prestressed concrete beams. The effects of prestressing force and stirrup can be observed as important factors to the failure mechanism. The simplified truss model, having a small number of degrees of freedom, has been modified and proposed by adapting the formulation to predict the angle of concentrated stress flow and the thickness of diagonal compression members for evaluating the shear carrying capacity of externally prestressed concrete beams. The predicted results show the good agreement with experimental results.

This paper develops an Audio-Visual Speech Recognition (AVSR) method, by (1) exploring high-performance visual features, (2) applying audio and visual deep bottleneck features to improve AVSR performance, and (3) investigating effectiveness of voice activity detection in a visual modality. In our approach, many kinds of visual features are incorporated, subsequently converted into bottleneck features by deep learning technology. By using proposed features, we successfully achieved 73.66% lipreading accuracy in speaker-independent open condition, and about 90% AVSR accuracy on average in noisy environments. In addition, we extracted speech segments from visual features, resulting 77.80% lipreading accuracy. It is found VAD is useful in both audio and visual modalities, for better lipreading and AVSR.

Background and Aim Healing speed of peptic ulcer is affected by a number of factors, including Helicobacter pylori (H. pylori) infection and intragastric pH. Acid inhibition exerted by proton pump inhibitors differs by CYP2C19 genotype. Herein, we investigated whether healing speed of artificial ulcers formed after endoscopic submucosal dissection (ESD) was influenced by H. pylori infection, CYP2C19 genotype, or other factors. Methods A total of 96 H. pylori-positive patients with gastric tumors scheduled for ESD were randomly assigned to receive eradication therapy for H. pylori before ESD (pre-ESD eradication) (n = 44) or after (post-ESD eradication) (n = 52). Patients received eradication therapy consisting of lansoprazole 30 mg, amoxicillin 750 mg, and clarithromycin 200 mg twice daily for 1 week. After ESD, lansoprazole 30 mg was given once daily for 8 weeks. Ulcer size was endoscopically measured on the next day and at 4 and 8 weeks after ESD. Results Mean reduction rate of artificial ulcer area in the pre-ESD eradication group was 94.7% ± 5.5% at 4 weeks, which was similar to that in the post-ESD eradication group (94.7% ± 6.7%, P = 0.987), irrespective of CYP2C19 genotype. In multivariate analyses, location of gastric tumor (middle and upper, odds ratio: 4.05, 95% CI: 1.620–10.230, P = 0.003) was a factor for 97% reduction of artificial ulcer area at 4 weeks post-ESD, but CYP2C19 genotype and H. pylori infection were not. Conclusion Healing speed of ESD-induced artificial ulcer was affected by tumor location, but not by time of H. pylori eradication, resected size, or CYP2C19 genotype.

The experiment and nonlinear FE analysis of concrete beams prestressed with external tendons were performed to investigate the flexural strength, the tendon stress, and to propose the equation for evaluating the tendon stress. Several parameters were examined in order to evaluate the significance of influential parameters. The analytical results were validated with the experimental investigations carried out in this study. From the parametric study, it indicates that the span-to-depth ratio has less significant effect on the tendon stress. However, the geometry of applied load must be taken into account for evaluating the tendon stress. Finally, the design equations to predict the tendon stress of such beams were proposed.

Pro-inflammatory cytokines initiate the vascular inflammatory response via upregulation of adhesion molecules on the endothelium. Recent observations suggest that reactive oxygen intermediates may play a pivotal role in TNF-alpha signaling and upregulate gene expression. We therefore evaluated the effects of pyrrolidine dithiocarbamate (PDTC; 0.1 mM) and spermine NONOate (Sper-NO; 1 mM) on adhesion molecule expression and nuclear factor kappa B (NF-kappaB) activation induced by TNF-alpha (10 ng/ml) in cultured human pulmonary microvascular endothelial cells (PMVEC). Treatment of cells with TNF-alpha for 4 h significantly induced the surface expression of E-selectin and ICAM-1. Treatment with TNF-alpha for 8 h significantly induced the surface expression of E-selectin, ICAM-1 and VCAM-1. The upregulation of these adhesion molecules was suppressed significantly by pretreatment with PDTC or Sper-NO for 1 h. 8-Bromo-cyclic GMP (1 mM) had no such effect, suggesting that the NO donor's effect was non-cGMP-dependent. The mRNA expression of E-selectin, ICAM-1 and VCAM-1, and activation of NF-kappaB induced by TNF-alpha for 2 h were decreased significantly by the above two pretreatments. N-acetylcysteine (10 mM) and S-nitroso-N-acetylpenicillamine (1 mM) had little inhibitory effects on the cell surface and mRNA expression of these adhesion molecules stimulated by TNF-alpha. Treatment with TNF-alpha for 4 h enhanced HL-60 leukocyte adhesion to human PMVEC, the effect of which was inhibited significantly by pretreatment with PDTC or Sper-NO. These findings indicate that both cell surface and mRNA expression of adhesion molecules in human PMVEC induced by TNF-alpha are inhibited significantly by pretreatment with PDTC or Sper-NO, possibly in part through blocking the activation of NF-kappaB. Although our in vitro results cannot be directly extrapolated to the in vivo situation, they suggest a potential therapeutic approach for intervention in cytokine-mediated inflammatory processes in the human lung.

To investigate the synergistic effects of heat load and hydrogen irradiation, cyclic heat load tests with a hydrogen beam and a comparable electron beam were performed for high purity CVD-tungsten coatings. Surface modification was examined as a function of the peak temperature by changing the heat flux. Scanning Electron Microscopy analysis showed that the surface damage caused by the hydrogen beam was more severe than that by the electron beam. In the hydrogen beam case, cracking at the surface occurred at all peak temperatures examined from 300 °C to 1600 °C. These results indicate that the injected hydrogen induces embrittlement for the CVD-tungsten coating.

The life of an abrasive wheel, in which cBN and Ni–P are co-deposited on a steel surface by electroless plating, is dependent on the grit adhesion and projection height. In electroless plating, it is difficult for Ni to deposit on ceramic grains. Therefore, surface shape at the grain periphery is not flat but sunken. In this study, with the aim of achieving higher grain support for the abrasive wheel, the surface shape at the grain periphery is improved with the application of ultrasonic vibration. The grain periphery of the specimen obtained with ultrasonic vibration (amplitude 11 mm) revealed an interface with about a 10 mm embossment at the periphery. In addition, the deposition rate with ultrasonic vibration is 1.6 times faster than that without it. This paper also demonstrated that the ideal interface between the cBN grits and Ni–P matrix is expected to have a heaped-up morphology, based on the results of a horizontal pushing-away test by a micro Vickers hardness tester for measuring the adhesive strength of grits. At the same time, the stress distribution around the grits in applying the lateral force to grit was simulated using the finite element method (FEM). The interfacial morphologies were observed between the cBN grits and Ni–P matrix which were prepared with and without ultrasound. It assumed a flat or slightly sunken shape without ultrasound, whereas it exhibited a heaped-up morphology with ultrasound. The heaped-up height and width depended upon the amplitude, and reached their the maximum at an amplitude of 11 mm. With the best interfacial morphology, the adhesive strength becomes 22% greater than that without ultrasound in the horizontal pushing-away tests. If the grit is pushed to 0.03 N, the maximum interface tensile stress without a heaped-up interface is about 160 MPa in stress analysis by FEM, whereas with such an interface (height: 11 mm; width: 7 mm), it is about 210 MPa, for an increase of about 20%. (Received February 8, 2005; Accepted June 6, 2005; Published September 15, 2005)

High heat flux experiments using a helium beam have been carried out on powder metallurgy tungsten. The energy of He is 19 keV. He beam flux and heat flux at the beam center is 2.0 × 1021 He/m2 s and 6.0 MW/m2, respectively. Beam duration is 3.0–3.9 s and interval of beam shot start is 30 s. The samples are irradiated up to a fluence of 1022–1024 He/m2 by the repeated irradiation pulses. In addition to the He beam irradiation, high heat flux experiments using hydrogen and electron beams have also been carried out on the samples. After the irradiation, surface modification by the irradiation has been investigated. Surface modification by helium and hydrogen beams is completely different from results of electron beam heating. In particular, helium beam heating causes remarkably surface modification such as a fine-scale rough surface at a peak temperature above 2400 °C.

Tungsten coated carbon fiber composite (CFC) is a candidate material for the high heat flux components in fusion reactors. In order to investigate the high-temperature properties at the joint interface of coating, heat load experiments by using electron beam were performed on VPS-tungsten coated CX-2002U samples. After the heat load test for 3.6 ks at 1400 °C, tungsten–rhenium multilayer (diffusion barrier for carbon) at the joint interface of coating was observed clearly. But, at the temperatures above 1600 °C, the multilayer was disappeared and a tungsten carbide layer was formed in the VPS-tungsten coating. At the temperatures below 1800 °C, the thickness of this layer logarithmically increased with increasing its loading time. At 2000 °C, the growth of the tungsten carbide layer was proportional to the square root of loading time. These results indicate that the diffusion barrier for carbon is not expected to suppress the carbide formation at the joint interface of the VPS-tungsten coating above 1600 °C.

A vertical InGaN-based blue light emitting diode (LED) with a reflective metal electrode and thick gold plated base free from insulating sapphire is demonstrated. A 50 μm-thick gold plated layer on a highly reflective platinum p-side ohmic contact is formed on the InGaN-based LED epi-structure, followed by irradiation with high power ultra-violet pulsed laser from the backside of the original sapphire substrate. The laser processing, so called laser lift-off technique, enables the separation of sapphire by decomposition of interfacial GaN layer. No transparent electrode is necessary for the LED because the current can spread well through the highly conductive n-GaN layer so that uniform blue light is emitted through the n-GaN layer. The electroluminescence (EL) spectra show small multi peaks due to the resonance within the formed vertical cavity. In addition, the measured thermal resistance of the vertical LED is smaller than that of the conventional LED on poor heat-conductive sapphire. The vertical LED would increase the brightness together with smaller chip size and lower series resistance. This would be advantageous espacially for high power and highly efficient LEDs applicable to future solid state lighting. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The p-i-n diodes were fabricated using 31 /spl mu/m thick n/sup -/- and p-type 6H-SiC epilayers grown by horizontal cold-wall chemical vapor deposition (CVD) with nitrogen and aluminum doping, respectively. The diode exhibited a very high breakdown voltage of 4.2 kV with a low on-resistance of 4.6 m/spl Omega/cm/sup 2/. This on-resistance is lower (by a factor of five) than that of a Si p-i-n diode with a similar breakdown voltage. The leakage current density was substantially lower even at high temperatures. The fabricated SiC p-i-n diode showed fast switching with a turn-off time of 0.18 /spl mu/s at 300 K. The carrier lifetime was estimated to be 0.64 /spl mu/s at 300 K, and more than 5.20 /spl mu/s at 500 K. Various characteristics of SiC p-i-n diodes which have an advantage of lower power dissipation owing to conductivity modulation were investigated.

GaN-based Gate Injection Transistors (GITs) with p-type gate over AlGaN/GaN heterojunction serve normally-off operations with low on-state resistances owing to the conductivity modulation by injection of holes. Established basic technologies on the GIT have shown promising features for switching applications. Further improvement of the performances would extend the applications and lead to the widespread use. In this paper, recent technologies on the GITs to improve the performances and extract the full potential are described. These include extension of the wafer diameter of Si up to 8 inch, InAlGaN quaternary alloy to reduce the series resistances, shortening the gate length to improve the device performances, integration of the gate driver and flip-chip assembly for faster switching.

Human behavior sensing and their analysis are great role to improve service quality and education of employees. This paper shows novel frameworks of detection of customer communication and lead time estimation(LTE) by using multi-sensored data, sound data and accounting data in the restaurant. They are useful for management about work environments and problems for employees. Lead time from order to delivery shows the quality of the service for customers. We found sound data of an employee's speech is useful for these techniques by speech ratio smoothing and POS sound detection.

Congenital absence of a single pulmonary valve cusp is extremely rare. We report a case of a 38-year-old woman with a confirmed congenital absence of a single pulmonary valve cusp associated with dextrocardia. The other 2 leaflets were moderately hypoplastic, and transthoracic echocardiography showed severe pulmonary regurgitation. This combination of lesions has not been reported previously. Pulmonary valve replacement using a composite biologic valved conduit was performed with an excellent outcome.

In this paper, we present a novel compact DC-DC converter IC in which normally-off GaN-GITs (Gate Injection Transistors) and gate drivers are integrated into one chip. The DC-DC converter IC can achieve higher efficiency and smaller chip size by reducing parasitic inductances between switching power devices and gate drivers. The gate driver, having a DCFL (Direct Coupled FET Logic) with a buffer amplifier which is consisted of a GaN-HFET (Hetero-junction FET) and GaN-GITs can operate with higher speed and lower power consumption. The fabricated DC-DC converter IC exhibits a peak efficiency as high as 86.6% at 2MHz for the 12V-1.8V conversion.