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Abstract We investigated annealing effects of La1−xSrxMnO3 (x = 0–0.6) on electrical resistivity and the temperature coefficient of resistivity (TCR). The annealed samples’ resistivity was lower than those of non-annealed samples. For example, annealing changed the resistivity of x = 0.3 at 25 °C from 4.50 × 10−5 to 3.71 × 10−5 Ω m. Remarkable difference in TCR was observed after annealing, for x = 0.3, 0.45, and 0.5. For x = 0.3, the TCR after annealing was 4000 ppm/°C, which was 1250 ppm/°C greater than that before annealing. We investigated (1) crystal phase, (2) Mn average valence, (3) Mott insulator–metal transition temperature, and (4) microstructure. The microstructure was remarkably varied for annealed x = 0.3 and 0.5. The average grain size of the x = 0.3 increased from 1.60 up to 2.38 μm. Results show that annealing affects resistivity and TCR because of grain growth during annealing.

Abstract We investigated annealing effects of La1−xSrxMnO3 (x = 0–0.6) on electrical resistivity and the temperature coefficient of resistivity (TCR). The annealed samples’ resistivity was lower than those of non-annealed samples. For example, annealing changed the resistivity of x = 0.3 at 25 °C from 4.50 × 10−5 to 3.71 × 10−5 Ω m. Remarkable difference in TCR was observed after annealing, for x = 0.3, 0.45, and 0.5. For x = 0.3, the TCR after annealing was 4000 ppm/°C, which was 1250 ppm/°C greater than that before annealing. We investigated (1) crystal phase, (2) Mn average valence, (3) Mott insulator–metal transition temperature, and (4) microstructure. The microstructure was remarkably varied for annealed x = 0.3 and 0.5. The average grain size of the x = 0.3 increased from 1.60 up to 2.38 μm. Results show that annealing affects resistivity and TCR because of grain growth during annealing.

The authors develop a long-term Japanese domestic refuse-fired power generation model which is capable of assessing the reverse-power-flow energy to the electric utility over a period of up to 20 years. The authors have sought to construct the model so that it can perform its assigned task with as simple a modelling system as possible. The model structure is fully documented and a brief summary of results is given. >

The authors develop a long-term Japanese domestic refuse-fired power generation model which is capable of assessing the reverse-power-flow energy to the electric utility over a period of up to 20 years. The authors have sought to construct the model so that it can perform its assigned task with as simple a modelling system as possible. The model structure is fully documented and a brief summary of results is given. >

Abstract Fatigue crack growth thresholds ΔKth for metals are provided in many fitness-for-service codes. However, fatigue crack growth thresholds at negative stress ratios are not consistently defined. There are two forms of thresholds at negative stress ratios: constant thresholds irrespective of stress ratios, or increasing thresholds with decreasing stress ratios. The definitions of the thresholds at negative stress ratios also take two forms: either ΔKth = Kmax−Kmin, or ΔKth = Kmax. ASME Section VIII, Section XI (ferritic steel) and International Institute of Welding (IIW) give constant thresholds expressed by ΔKth = Kmax. American Petroleum Institute (API) 579 and ASME Section XI (stainless steel) give increases in thresholds with decreasing stress ratios and the thresholds are expressed by ΔKth = Kmax−Kmin. British Standard (BS) 7910 gives constant thresholds expressed by ΔKth = Kmax−Kmin. The fatigue crack growth thresholds differ significantly among different fitness-for-service (FFS) codes. Appropriate thresholds for ferritic steels, stainless steels, and aluminum alloys are demonstrated in the literature survey.

Abstract Fatigue crack growth thresholds ΔKth for metals are provided in many fitness-for-service codes. However, fatigue crack growth thresholds at negative stress ratios are not consistently defined. There are two forms of thresholds at negative stress ratios: constant thresholds irrespective of stress ratios, or increasing thresholds with decreasing stress ratios. The definitions of the thresholds at negative stress ratios also take two forms: either ΔKth = Kmax−Kmin, or ΔKth = Kmax. ASME Section VIII, Section XI (ferritic steel) and International Institute of Welding (IIW) give constant thresholds expressed by ΔKth = Kmax. American Petroleum Institute (API) 579 and ASME Section XI (stainless steel) give increases in thresholds with decreasing stress ratios and the thresholds are expressed by ΔKth = Kmax−Kmin. British Standard (BS) 7910 gives constant thresholds expressed by ΔKth = Kmax−Kmin. The fatigue crack growth thresholds differ significantly among different fitness-for-service (FFS) codes. Appropriate thresholds for ferritic steels, stainless steels, and aluminum alloys are demonstrated in the literature survey.

Although laser processing is widely used for many applications, the cutting quality of carbon fiber reinforced plastic (CFRP) decreases around the heat-affected zone (HAZ) during laser processing. Carbon fibers are exposed around the HAZ, and tensile strength decreases with increasing length of the HAZ. Some theoretical studies of thermal conductions that do not consider fluid dynamics have been performed; however, theoretical considerations that include the dynamics of laser ablation are scarce. Using removed mass and depth observed from experiments, the dynamics of laser ablation of CFRP with high-temperature and high-pressure of compressive gas is simulated herein. In this calculation, the mushroom-like shape of laser ablation is qualitatively simulated compared with experiments using a high-speed camera. Considering the removal temperature of the resin and the temperature distribution at each point on the surface, the simulation results suggest that a wide area of the resin is removed when the processing depth is shallow, and a rounded kerf is generated as the processing depth increases.

Although laser processing is widely used for many applications, the cutting quality of carbon fiber reinforced plastic (CFRP) decreases around the heat-affected zone (HAZ) during laser processing. Carbon fibers are exposed around the HAZ, and tensile strength decreases with increasing length of the HAZ. Some theoretical studies of thermal conductions that do not consider fluid dynamics have been performed; however, theoretical considerations that include the dynamics of laser ablation are scarce. Using removed mass and depth observed from experiments, the dynamics of laser ablation of CFRP with high-temperature and high-pressure of compressive gas is simulated herein. In this calculation, the mushroom-like shape of laser ablation is qualitatively simulated compared with experiments using a high-speed camera. Considering the removal temperature of the resin and the temperature distribution at each point on the surface, the simulation results suggest that a wide area of the resin is removed when the processing depth is shallow, and a rounded kerf is generated as the processing depth increases.

Abstract The thermal properties of 4-hydroxyphenyl 4-(4-alkoxybenzoyloxy)benzoates (1), 4-(4-alkoxyphenox-ycarbonyl)phenyl 4-hydroxybenzoates (2), 4-(4-alkoxybenzoyloxy)phenyl 4-hydroxybenzoates (3), 4-hydroxyphenyl 4-(4-alkoxyphenoxycarbonyl)benzoates (4) and some related compounds have been examined. The nematic-isotropic and smectic A-nematic transition temperatures are compared with those of the related compounds having a methoxy group and a chlorine atom instead of the hydroxy group. The results indicate that the mesomorphic properties are almost independent of the hydrogen bonding at the terminal position. On the other hand, the effect of the hydrogen bonding is recognized in the smectic properties in some binary mixtures consisting of the hydroxy compounds and aryl acids. The effect of hydrogen bonding on mesomorphic properties is discussed.

Abstract The thermal properties of 4-hydroxyphenyl 4-(4-alkoxybenzoyloxy)benzoates (1), 4-(4-alkoxyphenox-ycarbonyl)phenyl 4-hydroxybenzoates (2), 4-(4-alkoxybenzoyloxy)phenyl 4-hydroxybenzoates (3), 4-hydroxyphenyl 4-(4-alkoxyphenoxycarbonyl)benzoates (4) and some related compounds have been examined. The nematic-isotropic and smectic A-nematic transition temperatures are compared with those of the related compounds having a methoxy group and a chlorine atom instead of the hydroxy group. The results indicate that the mesomorphic properties are almost independent of the hydrogen bonding at the terminal position. On the other hand, the effect of the hydrogen bonding is recognized in the smectic properties in some binary mixtures consisting of the hydroxy compounds and aryl acids. The effect of hydrogen bonding on mesomorphic properties is discussed.

Human action understanding and analysis for various applications are still in infancy due to various factors. In this paper, for recognizing various complex activities, a combined cue for motion representation and later recognition is demonstrated based on the optical flow-based four directional motion history and basic energy images. Optical flow between consecutive frames are computed to create the update function and to segment the moving regions. These motion vectors are split into four different channels. From these channels, the corresponding four directional history templates are computed. These along with frame-subtracted energy motion templates represent the final motion information of an action sequence. From these templates, feature vectors are calculated according to the seven Hu invariants. We develop a 35-dimensional feature vector for each action. For classification, k-nearest neighbor classification scheme is employed. For partitioning scheme, we employ leave-one-out cross-validation method. Both indoor and outdoor dataset provide satisfactory recognition results. These analysis, representation can be used for robot vision, interactive systems, computer games, behavior understanding, etc.

Human action understanding and analysis for various applications are still in infancy due to various factors. In this paper, for recognizing various complex activities, a combined cue for motion representation and later recognition is demonstrated based on the optical flow-based four directional motion history and basic energy images. Optical flow between consecutive frames are computed to create the update function and to segment the moving regions. These motion vectors are split into four different channels. From these channels, the corresponding four directional history templates are computed. These along with frame-subtracted energy motion templates represent the final motion information of an action sequence. From these templates, feature vectors are calculated according to the seven Hu invariants. We develop a 35-dimensional feature vector for each action. For classification, k-nearest neighbor classification scheme is employed. For partitioning scheme, we employ leave-one-out cross-validation method. Both indoor and outdoor dataset provide satisfactory recognition results. These analysis, representation can be used for robot vision, interactive systems, computer games, behavior understanding, etc.

Abstract Ethanol production was carried out by growing yeast cells immobilized on porous cellulose carriers. The effects of the chemical modification of cellulose carriers on cell immobilization and ethanol production were examined with respect to ion-exchange capacity and chemical structure. The ion-exchange capacity of 0·1 meq/g-carriers had no effect on immobilization but affected ethanol production by repeated batch cultures using immobilized yeast cells. Diethylaminoethyl was a suitable function group for immobilization and ethanol production. Ethanol productivity of the 10th batch cycle with diethylaminoethyl cellulose carriers was 23% greater than that of the first batch cycle.