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21.
We have investigated the microstructure of the poly(vinyl alcohol) (PVA) films using small- and wide-angle X-ray scattering (SAXS and WAXS, respectively) techniques. The samples were uniaxially drawn in water or KI/I2 aqueous solution and then dried in an air-oven at 333 K for 1 h prior to SAXS and WAXS measurements. It was found that for the films drawn in KI/I2 solution PVA chains in the microfibrillar structure are more extended upon the film drawing compared to the case of the films drawn in pure water, which is resulted from the correlation function analysis on the SAXS data. Adsorbed iodines into the film were anticipated to act as junction points between the microfibrils via the formation of the PVA-iodine complexes.  相似文献   
22.
4‐Aryl‐2(1H)‐quinolones were efficiently synthesized via copper‐catalyzed hydroarylation of (o‐aminophenyl)propiolates with arylboronic acid neopentyl glycol esters. The substrate propiolates were prepared from the corresponding silylalkynes with carbon dioxide by Kondo’s carboxylation method using N,N‐dimethylformamide as a solvent. Hydroarylation was performed in the presence of 3 mol% copper(II) acetate in methanol at 28 °C for 12 h and subsequent deprotection using trifluoromethanesulfonic acid (3.0 equiv.) at 65 °C for 2 h in the same pot to afford the desired 4‐aryl‐2(1H)‐quinolones in 39–89% yields.

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This paper presents a new nonintrusive appliance load monitoring technique based on integer programming. Nonintrusive appliance load monitoring is the problem of identifying the operating conditions of electric appliances in a house by observing only the overall load current and voltage. Since the overall load current is expressed as a superposition of the currents of the operating appliances, the monitoring problem can be formulated as an integer quadratic programming problem by expressing the operating conditions as integer variables. This problem is solvable with a sufficiently small computational burden thanks to the recent development of commercial software. The proposed method does not require relearning even when a new appliance is installed in the house. Furthermore, the proposed formulation is applicable to cases in which some appliance has multiple modes, and cases in which some appliances of the same type are operating simultaneously. The usefulness of the proposed technique is verified by experimental results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(2): 18–25, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21040  相似文献   
26.
We have developed an innovative power generation scheduling method using quadratic programming (QP). The advantage of using our method is that it simultaneously solves unit commitment and economic load dispatch. We relax the binary variables of the unit state into continuous variables to apply QP to this problem. We also add a penalty term to converge the value of those variables to 0 or 1 to the objective function: the sum of the fuel costs and the start‐up costs. This penalty term depends on the per‐unit fuel cost. The possibility of its variable converging to zero increases as the cost increases. This method was applied to a test system of daily generation scheduling that consisted of 29 thermal units, two pumped‐storage units, four cascaded hydro units, and one transmission. The schedule satisfied all constraints, that is, load‐power balance, operation reserve, power flow, minimum up/down‐times, and fuel consumption. This result shows that the proposed method is effective. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(1): 25–34, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21014  相似文献   
27.
This paper describes the phenomenon of internal pressure‐rise due to arcs ignited between metal rod electrodes in air. First, the internal pressure‐rises in a closed chamber due to arcs were measured at currents within the range of 1 to 12.5 kA. The rod electrodes were made of copper, iron, and aluminum, and were 20 mm in diameter. The measurements showed that the maximum pressure‐rise distinctly differed with each electrode material at the same total arc energy, namely, the maximum pressure‐rise was the highest in the case of the aluminum electrode and was the lowest in the case of the iron electrode. Next, to quantitatively verify this difference, the internal pressure‐rise was estimated, taking into account the energy balance in the closed chamber on each electrode material. It was found that the estimated pressure‐rise approximately agreed with the above experimental results by taking into consideration oxidation reactions of the electrodes, melting and vaporization of the electrodes, and radiation loss of the arcs under certain realistic assumptions. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(4): 9–18, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21071  相似文献   
28.
Tamada  Tsutomu  Ueda  Yu  Kido  Ayumu  Yoneyama  Masami  Takeuchi  Mitsuru  Sanai  Hiroyasu  Ono  Kentaro  Yamamoto  Akira  Sone  Teruki 《Magma (New York, N.Y.)》2022,35(4):549-556
Magnetic Resonance Materials in Physics, Biology and Medicine - Image quality (IQ) of diffusion-weighted imaging (DWI) with single-shot echo-planar imaging (ssEPI) suffers from low signal-to-noise...  相似文献   
29.
This paper describes experimental and analytic studies on pressure rise and propagation phenomena due to high current arcs in a container with opened pipes. The shape of the experimental container was chosen taking into account underground common ducts. First, arcs were ignited in the container with varying diameter D and length L of the opened pipes and at arc currents of 4 kA to 12.5 kA and an arc duration of 0.1 s. Based on measured waveforms, the maximum pressure rise and the pressure oscillation frequency were obtained. It was found that there is a tendency for to increase with decreasing D and increasing L, and that D has a much greater impact on . In addition, the tendencies of with changing D and L can be approximately explained by Helmholtz resonance. Second, a CFD model for the container with opened pipe was developed based on the experimental results, and simulations were performed. The simulation results were found to correspond to the experimental pressure rise.  相似文献   
30.
An audio visual system can enhance its controllability by an interactive and user-friendly menu through which a user issues commands to control audio visual devices. One of the serious problems encountered in such menu development is that end-user's requirement specifications vary in screen layouts, device configurations and commands contents, and often involves extensive manual programming. We have definedMacroMMenu formally as a tree structure menu system model restricting a menu transition graph, and designed and implemented an automated menu prototyping system which includes a menu generator calledInteractive Proto. UsingInteractive Proto through a visual programming language, end-users themselves, who are usually non-programmers, can easily define menu specification, input this source specification, and the targetMacro Menu is generated automatically.  相似文献   
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