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151.
Heat insulating and acoustic absorbing materials were endued with fireproof performance and subjected to quantitative evaluations assuming a variety of uses and situations. Fireproofing was performed by spraying an aqueous solution of flame retardants on raw materials (wood shavings, kenaf bast fibers, and core-sheath-type fibers) during the fiber spreading and mixing step. It was possible to treat the materials homogeneously and without increasing manufacturing workload. Flame retardancy was evaluated using vertical flame testing, horizontal flame testing, the 45° Meckel’s Burner method, and a cone calorimetry method in accordance with UL94, JIS D 1201, JIS L 1091, and JIS A 9521, respectively. It was possible to achieve results that satisfied each of these standards, along with quantifying the relations between treatment conditions and performance.  相似文献   
152.
The perusal of literatures revealed that simultaneous malignant transformation of predisposing ovarian endometrioid tumor and uterine adenomyosis is a rare occurrence. A case report of endometrioid carcinoma in the right ovary and malignant transformation of adenomyosis in the uterus in a 52-year-old female was described. Both foci were histologically classified as mature adenoacanthoma and separately originated from the so-called endometriosis. There is no continuity associated with metastasis between the two carcinoma foci.  相似文献   
153.
This paper considers a 1-unit system; the unit is repaired upon failure. The failure and repair rates need not be constant. The system fails if the unit is not repaired within a fixed time, or if the number of failures during the mission exceeds a fixed number. As a special case, that number is allowed to be ``infinite.' The Laplace transforms of the reliability and mean time to system failure are derived; they are not easily solved. The special case of constant failure and repair rates is treated. The results are compared with those of Calabro.  相似文献   
154.
The authors provide initial documentation that juvenile rats emit short, high-frequency ultrasonic vocalizations (high USVs, approximately 55 kHz) during rough-and-tumble play. In an observational study, they further observe that these vocalizations both correlate with and predict appetitive components of the play behavioral repertoire. Additional experiments characterized eliciting conditions for high USVs. Without prior play exposure, rats separated by a screen vocalized less than playing rats, but after only 1 play session, separated rats vocalized more than playing rats. This findings suggested that high USVs were linked to a motivational state rather than specific play behaviors or general activity. Furthermore, individual rats vocalized more in a chamber associated with play than in a habituated control chamber. Finally, congruent and incongruent motivational manipulations modulated vocalization expression. Although play deprivation enhanced high USVs, an arousing but aversive stimulus (bright light) reduced them. Taken together, these findings suggest that high USVs may index an appetitive motivation to play in juvenile rats.  相似文献   
155.
A simple instrumentation system is developed for determining the elastic moduli of engineering ceramics and their composites from the sound produced by the impact of a sphere on a specimen which is suspended by thin wires or ceramic threads in a furnace. The natural frequencies of the flexural and torsional vibration modes are measured from the impact noise by using a fast Fourier transform analyzer. Elastic moduli are then computed from those frequencies by using Timoshenko's beam theory and also Saint-Venant's torsion theory. The validity of the measurementmethod is demonstrated by room-temperature tests on ceramic and metallic specimens of known elastic moduli. SiAION and Al-Al2O3 composites are tested at elevated temperatures up to 900°C. It is shown that the Young's and shear moduli of the materials tested decrease with an increase in temperature, while Poisson's ratio remains almost constant.  相似文献   
156.
The distribution of time to failure for a system consisting of two dissimilar, redundant, repairable units is discussed. The system fails if it stays inoperable for more than a fixed time interval, measured from the instant at which both units broke down. The Laplace transform of time to system failure, and the explicit formula for the mean time to system failure in the special case are derived.  相似文献   
157.
158.
Abstract— The development of multi‐primary‐color (MPC) display systems is one of the big paradigm shifts in recent display technologies and induces new potentials of display devices. The development of MPC display systems for different goals is briefly reviewed. Especially, by employing MPC systems, it is possible to reproduce the real material colors faithfully and efficiently. For signal processing, MPC systems have a big advantage in the so‐called color‐reproduction redundancy. A number of applications can be derived from this characteristic, such as improving the viewing‐angle dependency issue and power savings. On the other hand, MPC systems have a typical trade‐off versus RGB‐standardized input signals, especially for reproducing bright green. New algorithms to moderate this trade‐off on MPC systems by employing color‐reproduction redundancy are proposed. The goal of our algorithms is to maintain the compatibility with RGB‐based input signals though the initial display design so that the characteristics of MPC systems are not changed or lost. These algorithms indicate that MPC display systems are applicable not only for a specifically limited objective but also for other applications, e.g., TV broadcasting.  相似文献   
159.
Since 1998, Japan Soap and Detergent Association has been continuously evaluating the concentrations of four surfactants used in household detergents and fabric conditioners in river surface water: linear alkylbenzene sulfonate (LAS), polyoxyethylene alkyl ether (AE), alkyldimethylamine oxide (AO) and dialkyl dimethylammonium chloride (DADMAC) in Japanese urban rivers, in order to assess the risks of surfactants on aquatic organisms. Surfactant concentrations in the river water in June and September were found to be lower than those in March and December, the season where water temperature is lower, suggesting that the rates of biodegradation in environmental water differ depending on the water temperature. All the measured surfactant concentrations were below the reported predicted no-effect concentration (PNEC) and have been decreasing year by year; suggesting that surfactant risk on aquatic organisms in Japanese rivers is low under current conditions.  相似文献   
160.
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