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In this paper, a hybrid approach of the constrained interpolation profile (CIP) method and the transmission line modeling (TLM) method has been proposed for analyzing lightning electromagnetic fields and surges in the three-dimensional Cartesian coordinate system. The TLM method is employed locally in the working space for representing thin-wire conductors, and the CIP method is used for computing fields in the rest of the working space. Waveforms of lightning electromagnetic fields and surges computed using the CIP-TLM hybrid method agree well with corresponding ones computed using exact analytical expressions or with the finite-difference time-domain method.

We demonstrate the characteristics of photonic crystal lasers fabricated by air hole retained regrowth using metal-organic vapor-phase epitaxy based on an organic arsenic source [tertiary-butyl arsine (TBAs)]. TBAs has the advantage of high decomposition efficiency compared with AsH3, which enables us to achieve a unique air hole shape under the crystal regrowth. We demonstrate that photonic crystal lasers with an area of $200 \times 200~\mu \text{m}^{2}$ exhibit single-mode lasing with a low lasing threshold of ~0.5 kAcm−2. The effect of the unique shape of the air holes obtained by the TBAs-based regrowth on the laser performance is discussed using coupled-wave theory.

We investigate the propagation of light in an ultra-thin gap in stacked-stripe three-dimensional (3D) photonic crystals operating in the near-infrared wavelength range. We fabricate 3D photonic crystals composed of 32 stacked layers with an artificially introduced gap (∼200 nm) in the center of the structure by using a wafer bonding method. In order to study the characteristics of the gap, we introduce oblique waveguides to connect the gap with the upper and lower sides of the photonic crystal. The observation of light output from waveguides that are distant from the waveguide used for incident light demonstrates for the first time that light propagates along the air gap and is distributed to multiple output waveguides. Moreover, we perform calculations that reveal the formation of a propagation mode resulting from introduction of the ultra-thin gap. We analyze the coupling between the propagation mode and the oblique waveguide mode and discuss the characteristics of light distribution via the gap.

Deep ultra-violet (DUV) laser and short pulse lasers are used for laser processing, because they can decrease the heat effect for process materials. We are developing a hybrid ArF excimer laser that is consists of a solid-state laser, multi wavelength conversion and ArF excimer amplifier. This laser can generate DUV light of 193 nm wavelength short pulse width. In this research, we demonstrated laser drilling on ultra-high temperature structural material that is silicon carbide ceramic matrix composites (SiC-CMC) using high peak power DUV laser. The removal rate was 150 nm/shot with 460 ps pulse. This rate was more than 4 times higher than ArF excimer laser (20 ns pulse width). The HAZ was also reduced by using high peak power DUV light source.

We report a 193 nm solid state laser based on 1030 nm laser and 1550 nm laser which is generated by two-stage OPA. 110 mW output power and 0.5 pm spectral width was achieved.

It is well known that some cerate based or zirconate based perovskites exhibit proton (H+) conduction at around 600oC [1], and those proton conducting perovskites are expected to be used as electrolyte of proton ceramic fuel cells (PCFCs). Especially, Y-doped BaZrO3 (BZY) has received attention, owing to its higher H+ conductivity than other proton conducting perovskites. However, the densification of BZY basically needs high temperature above 1400oC, leading to a critical problem when the BZY film was prepared on a Ni-based composite electrode; BZY significantly reacts with Ni and forms impurity phase such as BaY2NiO5 during the high temperature sintering [2]. In addition, this impurity phase easily decomposes under H2 atmosphere and causes the critical damage for the cell. D. Han et al. have reported that the BaY2NiO5 impurity phase disappears by heating above 1500oC [4]. However, they also have reported that Y2O3 alternatively appears in the high temperature heating [4]. Thus, a preparation technique that can fabricate thin film at lower temperature, is favorable to avoid the formation of the impurity phase in the case of BZY. Currenlty, the pulse laser deposition (PLD) method has been commonly utilized for the lower temperature deposition of ceramic thin films. However, in the case of PLD, its deposition rate is usually 1 μm/h and its area is several cm2 at best, that is, PLD has a difficulty for the practical use. Besides the PLD method, the laser chemical vapor deposition (LCVD) method, which combines a chemical vapor deposition and laser irradiation, has been proposed as one of the low temperature deposition methods. Recently, Goto et al. have demonstrated the laser chemical vapor deposition of the ceramic thin films at a lower temperature [5,6], and actually, they reported the high-speed deposition of TiN film at several 10 μm/h at 600oC- 800°C [5]. In addition, they demonstrated LCVD on a curved surface and a large surface area [6]. Thus, in this work, the preparation of the BZY film was investigated by using LCVD. The deposited BZY film was characterized by XRD, SEM and EDX, and its properties such as structure and chemical composition were analyzed in detail. As a result, it was revealed that the uniform BZY thin film with columnar structure was successfully deposited by the LCVD method. In addition, the thickness of the BZY film was about 16 μm even though its deposition time was only 10 min, suggesting the high speed deposition of BZY film is possible by using the LCVD. [1] H. Iwahara, T. Esaka, H. Uchida, N. Maeda, Solid State Ionics 3/4 (1981) 359-363. [2] L. Bi, E. Fabbri, Z. Sun, E. Traversa, J. Electrochem. Soc. 158 (2011) B797-B803. [3] S. Fang, S. Wang, K. S. Brinkman, Q. Su, H. Wang, F. Chen, J. Power Sources 278 (2015) 614-622. [4] D. Han, Y. Otani, Y. Noda, T. Onishi, M. Majima, T. Uda, RSC Adv. 6 (2016) 19288-19297. [5] Y. S. Gong, R. Tu, T. Goto, J. Alloys Compd. 485 (2009) 451-455. [6] T. Goto, SOKEIZAI 51 (2010) 20-25.

This study investigated the preparation of an Y-doped BaZrO3 (BZY) thin film electrolyte by a laser chemical vapor deposition (LCVD). The structure, chemical composition, and other properties of the deposited BZY film were analyzed in detail by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. These analyses revealed that a uniform BZY thin film consisting of columnar structures was successfully deposited by the LCVD method. In addition, the thickness of the BZY film was about 16 μm, even though the deposition time was only 10 min, indicating that high-speed deposition of the BZY film was achieved by the LCVD method.

To overcome global warming issue and energy shortage problem, economical hydrogen production technologies from renewable energy or unused fossil fuel with carbon capture technology are being developed all over the world. However it becomes the large problem that it is necessary to reconstruct energy infrastructures for production, transportation and usage of hydrogen and to entail a vast cost. Against this problem, for effectively utilizing existing energy infrastructures, we are developing a methane producing technique from water and carbon dioxide by using renewable electricity instead of hydrogen production. Specifically, solid oxide electrolysis cell (SOEC) technology for producing syn-gas with high efficiency has been developed and we have succeeded in trial manufacture tubular SOECs whose sin-gas production rate is more than 3.5 sccm/cm2 at the operating temperature of 750 oC and electrolytic voltage of 1.35V. Therefore, in this paper, the numerical models of an SOEC methane production system and a conventional methane production system were made in reference to performance of the tubular SOECs and dependence of performance of the each system on operating conditions, such as operating temperature, feed gas composition, is analyzed and compared with each other. The methane producing system which combined a water electrolysis system with a high temperature water-gas shift reactor was considered as a conventional system. From the result of the analysis, advantage of SOEC methane production system is clarified.

In this paper, we demonstrate the operation of a photonic-crystal surface-emitting laser that has a double-hole two-dimensional photonic-crystal structure. We successfully fabricate this unique structure by employing air-hole retained crystal regrowth using metalorganic vapor phase epitaxy. Single-mode lasing having a narrow beam divergence of less than 0.2° is achieved with a large lasing area of 300×300 μm2.

A method to evaluate current efficiency was developed for high temperature electrolysis using solid oxide cells (SOECs). For a fuel electrode, depending on range, our gas analysis system achieved ±0.4-0.6% uncertainty for 10-90% mole fraction analysis of H2 and H2O. For an air electrode, O2 and N2 was measured with ± 0.2% and ±0.4% uncertainty, respectively. Case studies for both electrodes clarified that current efficiency can be evaluated with ±1.1-2.8% uncertainty at practical 90-50% steam utilizations in the case of ± 1.0% uncertainty in gas-flow-rate measurement.

We proposed an unique intuitive movement system which is equipped Omni-wheels with load cells for care-robots. In this systems, pilot or subjects can cotrol ituitively with difference of centroid position with load cells. This systems is constructed a cylinder structure stacking a disk on a triangular frame and installed 3 load cells and Omni-wheels. These load cells sensed position and centroid is calculated by microcomputer. This sensed centroid position is applied for calculating direction and speed and these information transferred to servo systems installed Omni-wheels. The system was investigated with transient response characteristics and error distance of centroid of the system. Transient response measurement of the servo system were under no-load or 60 kg loaded condition respectively. We observer that the system were possible to move under 60 kg load. Moreover, we cleared suitable rotating speed. Via the measuring error distance of centroid under loads, The maximum error distance was possible to operate accurately under heavy load like 60 kg human. We expect this Omni-directional mobile systems with intuitive operation is possible to be expected, novel and unique as novel care-robots technology.

BACKGROUND/OBJECTIVES Water-filtered broad-spectrum near-infrared irradiation can induce various biological effects, as our previous clinical, histological, and biochemical investigations have shown. However, few studies that examined the changes thus induced in gene expression. The aim was to investigate the changes in gene expression in a 3-dimensional reconstructed epidermal tissue culture exposed to water-filtered broad-spectrum near-infrared irradiation. METHODS DNA microarray and quantitative real-time polymerase chain reaction (PCR) analysis was used to assess gene expression levels in a 3-dimensional reconstructed epidermal model composed of normal human epidermal cells exposed to water-filtered broad-spectrum near-infrared irradiation. The water filter allowed 1000-1800 nm wavelengths and excluded 1400-1500 nm wavelengths, and cells were exposed to 5 or 10 rounds of near-infrared irradiation at 10 J/cm2 . RESULTS A DNA microarray with over 50 000 different probes showed 18 genes that were upregulated or downregulated by at least twofold after irradiation. Quantitative real-time PCR revealed that, relative to control cells, the gene encoding La ribonucleoprotein domain family member 6 (LARP6), which regulates collagen expression, was significantly and dose-dependently upregulated (P < 0.05) by water-filtered broad-spectrum near-infrared exposure. Gene encoding transcripts of collagen type I were significantly upregulated compared with controls (P < 0.05). CONCLUSIONS This study demonstrates the ability of water-filtered broad-spectrum near-infrared irradiation to stimulate the production of type I collagen.

Slurry coating method for fabricating tubular solid oxide electrolysis stacks operated at 700~800oC is developed. To improve cell performance at the low temperature, the thickness of the electrolyte layer is tried controlling about 10μm. By using this process, the SOEC stack whose input power is about 100 W is fabricated and its performance is measured. From the measurement, it is clarified that the hydrogen production rate at 750oC goes up to 678 sccm (3.08 sccm/cm2) at the thermoneutral voltage and steam utilization of 75 %. Furthermore, impedance of the stack is analysed by AC impedance method.

Tubular solid oxide electrolysis cells (SOECs) whose operating temperature is reduced to 700~800 oC are developed. To improve cell performance at the low temperature, Sc2O3 stabilized ZrO2 is chosen as electrolyte material and the thickness of the electrolyte layer is tried controlling about 10μm by slurry coating method. As a result of performance test, it is clarified that current density at thermoneutral point goes up to 0.46 Acm-2 at 750 oC. Furthermore, degradation phenomena in long term operation more than 1200 h are observed.

Soluble polythiophenes bearing strong electron withdrawing groups, dicyanoethenyl [CHC(CN)2] (PTDCN) and cyano-methoxycarbonylethenyl [CHC(CO2Me)CN] (PTCNME), in the side chains have been prepared. Optical band gaps calculated from onset absorption were 1.70 eV and 1.73 eV for PTDCN and PTCNME, respectively. Highest occupied molecular orbital energy levels measured with a surface analyzer (AC-2) were −5.53 eV and −5.29 eV for PTDCN and PTCNME, respectively, which were much lower than that of poly(3-hexylthiophene) (−4.81 eV). To investigate photovoltaic properties, bulk heterojunction polymer solar cells based on PTDCN and PTCNME were fabricated with a structure of ITO/PEDOT:PSS/active layer/LiF/Al, where the active layer was a blend film of polymer and [6,6]-phenyl C61 butyric acid hexyl ester (PC61BH). Solar cell parameters were estimated from current density–voltage (J–V) characteristics under the illumination of AM1.5 at 100 mW/cm2. The solar cell based on the blend film of PTCNME:PC61BH (1:1) showed power conversion efficiency (PCE) of 0.72% together with the open current voltage (Voc) of 0.61 V, the short current density (Jsc) of 3.90 mA/cm2, and the fill factor of 30.3%. The PCE of a solar cell fabricated from PTDCN in a similar way was 0.56%. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

Tubular SOECs with operating temperature reduced to 700~800oC are developed. To improve cell performance at low temperatures, Sc2O3 stabilized ZrO2 is chosen as the electrolyte material and thickness of the electrolyte layer is tried to be controlled to about 10 μm. Test electrolysis cells are fabricated by using slurry coating method. Dependence of cell performance on operating conditions is measured. Further, AC impedance method is applied to the cells to estimate interfacial overvoltage. From the experiment, it is clarified that the hydrogen production rate at 750oC goes up to 3.6 sccm/cm2 at the thermoneutral voltage. This value is more than 2 times of that of the commercial alkaline electrolysers.

Dimethyl ether steam reforming (DME SR) was performed over composite catalysts of copper ferrite spinel (CuFe2O4) and alumina for hydrogen production, applicable to fuel cell. A highly active composite was achieved when the calcination temperature of the Cu spinel was at 900 8C and thatof the aluminawas ator below 700 8C. The calcination temperature strongly affected the crystallinity and reducibility of thecopper ferrite spinel and the acidity of alumina. The composite catalysts both with and without pre-reduction were active for DME SR when the prereduced catalyst exhibited higher initial activity, butlonger activation process was observedfor the composite catalyst without pre-reduction.DME conversion and hydrogen production significantly depended on gas hourly space velocity (GHSV) and reforming temperatures (Tr). DME conversion (>95%), H2 production rate (� 50 mol kgcat � 1 h � 1 ), and H2 concentration (ca. 73%) were achieved at Tr of 350 8C and GHSV of 1500 h � 1 . The maximum H2 production rate of 120 mol kgcat � 1 h � 1 was found at Tr of 450 8C and GHSVof 4000 h � 1 . Mixing state of the copper spinel and thealuminawas alsoinvestigated.Aftermixing withalumina, thepresent CuFe2O4markedlyexhibitedexcellentactivityforDME SRin

For producing pure hydrogen with high efficiency and low cost, Solid oxide electrolysis cells (SOECs) assisted by low calorie gas were proposed. To use low coat metal as electrodes and an interconnector, tubular SOECs operated at 700~800oC were tried fabricated. The thickness of the electrolyte in the SOEC reduce to approximately 10 μm by using Slurry coating technique and electrolytic performance of the fabricated cells was measured. As a result of this experiment, the hydrogen production rate of a testing cell whose effective electrode area was 18.8 cm2 achieved 56 sccm at 800oC under practical operating condition. Further, the way of improving cell performance was discussed.

Higher CO conversions were achieved over Cu–Mn spinel catalysts prepared by citric acid complex method (CIT), urea homogenous coprecipitation (URE) and Pechini method (PEC) than by coprecipitation with NH3 (COP(NH3)). Higher reducibility was attained by CIT, URE and PEC than by COP(NH3). The citric acid method was a simple way to produce a catalyst with high activity. CO conversion was enhanced with a rise in calcination temperatures over the Cu–Mn spinel catalyst prepared by the citric acid method. Partial substitution of Fe or Al for Mn enhanced the catalytic activity of Cu–Mn spinel. Optimized Cu/Mn/Fe ratio was 1:1:1 in terms of catalytic activity.

Cu/MnO catalysts prepared via reduction of Cu–Mn spinel oxide were investigated for development of active Cu catalysts for the water gas shift reaction (WGSR). A Cu–Mn catalyst active for the WGSR was obtained after high temperature calcination at 900 °C and subsequent reduction. The optimum Cu/Mn ratio for catalytic activity of the Cu–Mn oxide system was 1/2. Nonstoichiometric Cu1.5Mn1.5O4 phase existed stably when copper manganese oxide was calcined above 700 °C. The optimized Cu–Mn spinel showed excellent WGSR activity when a larger percentage of CO was used, as in hydrocarbon reforming. Cu–Mn spinel oxides calcined above 900 °C were easily reduced. This may be responsible for the high activity of the Cu/MnO catalyst. Carbon dioxide in the reformed gas significantly depressed WGSR activity below 200 °C, while CO conversion reached equilibrium at 200 °C in the absence of CO2.

Objective: We aimed to compare the efficacies of rehabilitation with the hybrid assistive limb and conventional rehabilitation after total knee arthroplasty. Materials and methods: A total of 37 consecutive patients who underwent primary total knee arthroplasty for knee osteoarthritis were enrolled. Seven patients withdrew from the study after randomization, and 30 patients (hybrid assistive limb group: n = 16; conventional group: n = 14) completed the randomized controlled trial. Patients in the hybrid assistive limb group underwent ten 20-min rehabilitation sessions with the hybrid assistive limb as well as 20-min conventional sessions over the course of 2 weeks, whereas patients in the conventional group received ten 40-min conventional sessions during the same period. The primary outcome measure was walking speed, whereas the secondary outcome measures included quadriceps strength and knee pain assessed using a numerical rating scale. The outcome measures were evaluated prior to surgery and on postoperative weeks 1, 2, and 3. Results: In the early postoperative period, rehabilitation after total knee arthroplasty with the hybrid assistive limb resulted in a significantly greater improvement in walking speed (weeks 1 and 2: p = 0.045), quadriceps strength (weeks 1 and 2; weeks 1 and 3: p

A tubular Ni-8YSZ/SSZ/GDC/SSC (Strontium-doped Samarium Cobaltite) cell was prepared for high temperature co-electrolysis of H2O and CO2. This cell enhanced a current density at 750ºC by two-fold compared to a previous type of our cell. Measurements of voltage-current density (V-J) curves revealed that 0.55 A/cm2 was attained at 750ºC and a thermoneutral voltage (1.33 V). The V-J curves were not influenced by change of H2/C (= 2-4) or flow-rate ratio (= 1-4) of positive electrode to negative one. In addition, V-J curve measurement at constant 80% utilization of H2O and CO2 clarified that 0.41 A/cm2 was achieved at the thermoneutral voltage and 750ºC. It was observed by precise gas analyses that gas composition changed in proportion to J and utilization of H2O and CO2. Simultaneously, cross gas-leakages were detected from one electrode to the other.

Yohei Tanaka1,2, Kiyoshi Matsuo1, Shunsuke Yuzuriha11Department of Plastic and Reconstructive Surgery, Shinshu University School of Medicine, Matsumoto, Japan; 2Clinica Tanaka Plastic and Reconstructive Surgery and Anti-aging Center, Matsumoto, JapanBackground: We reported previously that near-infrared (NIR) irradiation provides long-lasting stimulation of elastin, and is efficient for skin rejuvenation. Many studies have indicated the efficacy of various types of laser, but did not include sufficiently objective evaluation. Therefore, we evaluated the efficacy of NIR laser treatment not only subjectively but also objectively.Methods: Fifty Japanese patients were treated with a NIR 1064-nm neodymium: YAG laser. Objective computer assessments were performed by Canfield VISIA Complexion Analysis for improvement of dilated pores, skin texture, and wrinkles. The volunteers then provided subjective assessments. Histological evaluations of elastin were performed by Victoria blue staining up to 90 days post-treatment in four Japanese volunteers.Results: Mean pretreatment percentiles of dilated pores, skin texture, and wrinkles were 51.08 ± 24.82, 54.7 ± 26.33, and 58.02 ± 28.61, respectively. Mean post-treatment percentiles of dilated pores, skin texture, and wrinkles were 53.58 ± 23.89, 58.58 ± 24.44, and 62.2 ± 25.39, respectively. All objective computer assessments evaluated by percentiles in dilated pores, skin texture, and wrinkles showed significant improvement after NIR laser treatment. Ninety-six percent, 100%, and 98% of volunteers reported satisfaction with the improvement of dilated pores, skin texture, and wrinkles, respectively. NIR laser treatment appeared to increase the amount of elastin at day 30, which then decreased slightly but was still elevated at day 90 compared with nonirradiated controls on day 0. Thickening of the epidermis was detected on day 30, and epidermal smoothness persisted for up to 90 days. No treatment-related adverse events were observed.Conclusions: NIR irradiation increased elastin in the dermis, and achieved skin rejuvenation. The results indicated that NIR irradiation provides safe and effective long-term stimulation of elastin, which is beneficial for improving dilated pores, skin texture, and wrinkles.Keywords: near-infrared laser, elastin, skin rejuvenation, objective assessment