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11.
Optoelectronics: High‐Performance Planar Perovskite Optoelectronic Devices: A Morphological and Interfacial Control by Polar Solvent Treatment (Adv. Mater. 23/2015) 下载免费PDF全文
12.
Kyung-Wan Kang Hyoung-Ho Doh Jung-Hyeon Park Dong-Ho Lee 《The International Journal of Advanced Manufacturing Technology》2016,82(9-12):1463-1473
We consider two interrelated problems that occurred in disassembly systems: disassembly leveling and lot sizing. Disassembly leveling, one of disassembly process planning decisions, is to determine disassembly structures that specify parts and/or subassemblies to be obtained from disassembling used/end-of-life products, and disassembly lot sizing is the problem of determining the amounts of disassembly operations required to satisfy the demands of their parts and/or subassemblies. Unlike the existing studies, this study considers the two problems at the same time for the objective of minimizing the sum of disassembly setup and operation costs. In particular, we consider a generalized version in which disassembly levels may be different even for products of the same type. Two types of the problem are considered in this study. The first one is the basic problem without parts commonality, i.e., products do not share their parts or subassemblies, for which a polynomial time optimal algorithm is suggested after developing a mathematical programming model. The second one is an extended problem with parts commonality. After developing another mathematical programming model for the extension, we prove that it is NP hard. Then, a heuristic algorithm is suggested together with its computational results. 相似文献
13.
Hyun?Tae?Jang Sang?Bum?KimEmail author Wang?Seog?Cha Sung?Chang?Hong Dong?Sup?Doh 《Korean Journal of Chemical Engineering》2003,20(1):138-144
The combustion characteristics of a mixture of anthracite and bituminous coal were studied in a 0.155 m i.d. fluidized bed
combustor (FBC). The properties of the pressure fluctuation for the bed such as the standard deviation, cross-correlation
function, dominant frequency and the power spectral density function were obtained through statistical analysis. To interpret
the combustion characteristics in the FBC with uniform or multi-sized particles of anthracitebituminous coal mixture, the
properties of pressure fluctuation were determined as a function of the particle size distribution and anthracite mixing fraction.
In the present work, it is known that the combustion region could be obtained from the analysis of pressure fluctuation properties,
and the mixed-firing of anthracite-bituminous coal is related to the reaction models of both coals and particle size distribution.
Moreover, the relation between coal size distribution and static mean pressure, and the ignition region could be obtained
from the mean pressure profile. 相似文献
14.
Euh Duck Jeong Hyun Ju Han Ok Sang Jung Myoung Gyu Ha Chil Hoon Doh Min Ji Hwang Ho-Soon Yang K.S. Hong 《Materials Research Bulletin》2012,47(10):2847-2850
Pure and metal (Cu, Al, Sn, and V)-doped Li4Ti5O12 powders are prepared with solid-state reaction method. The effects of dopants on the physical and electrochemical properties are characterized by using TGA, XRD, and SEM. Compared with pure Li4Ti5O12, metal-doped Li4Ti5O12 powders show structural stability and enhanced lithium ion diffusivity brought by doped metal ions. Voltage characteristics and initial charge–discharge characteristics according to the C rates in pure and metal-doped Li4Ti5O12 electrode materials are studied. Pure Li4Ti5O12 powder shows a relatively good discharge capacity of 164 mAh/g at a rate 0.2C, and some of metal-doped Li4Ti5O12 powders show higher discharge capacities. Metal-doped Li4Ti5O12 powders are promising candidates as anode materials for lithium-ion batteries. 相似文献
15.
We present a novel solution for topological exploration in corridor environments using cheap and error-prone sonar sensors.
Topological exploration requires significant location detection and motion planning. To detect nodes (i.e., significant places)
robustly, we propose a new measure, the eigenvalue ratio (EVR), which converts geometrical shapes in the environment into
quantitative values using principal component analysis. For planning the safe motion of a robot, we propose the circle following
(CF) method, which abstracts the geometry of the environment while taking the characteristics of the sonar sensors into consideration.
Integrating the EVR with the CF method results in a topological exploration strategy using sonar sensors approach. The practicality
of this approach is demonstrated by simulations and real experiments in corridor environments. 相似文献
16.
This article addresses a tracking controller design for a trailer system consisting of a steering tractor and a passive trailer linked with a rigid free joint and having nonholonomic constraints. We design the tracking controller using the Lyapunov direct method, for both forward and backward driving of the trailer system. Backward driving is unstable, and thus is more difficult than forward driving. In previous research, we proposed a globally asymptotically stable (GAS) tracking control for forward driving of a trailer system with nonholonomic constraints. In this article, we implement the GAS tracking controller for forward and backward driving, and perform experiments using visual feedback and remote control systems. The experimental results represent stable responses and demonstrate the effectiveness of our method. © 2002 Wiley Periodicals, Inc. 相似文献
17.
Chil-Hoon Doh Chul-Wan Park Hye-Min Shin Dong-Hun Kim Young-Dong Chung Seong-In Moon Bong-Soo Jin Hyun-Soo Kim Angathevar Veluchamy 《Journal of power sources》2008
A new anode composition comprising SiO and graphite(C) is prepared through a high-energy ball milling process. During the first cycle, the anode delivers high discharge and charge capacity values of 1556 and 693 mAh g−1, respectively. The electrode shows a reversible charge capacity value of 688 mAh g−1 at the 30th cycle with 99% Coulombic efficiency. X-ray diffraction analysis reveals that ball milling does not produce any new compound, but only causes a reduction in particle size. The irreversible and reversible capacities appear to be interdependent. 相似文献
18.
19.
Anaerobic digestion improvement can be accomplished by different methods. Besides optimization of the process conditions, pretreatment of input sludge and increase of process temperature is frequently used. The thermophilic process brings a higher solids reduction and biogas production, a high resistance to foaming, no problems with odour, better pathogens destruction and an improvement of the energy balance of the whole treatment plant. Disintegration of excess activated sludge in a lysate centrifuge was proved to cause increase of biogas production in full-scale conditions. The rapid thermal conditioning of digested sludge is an acceptable method of particulate matter disintegration and solubilization. 相似文献
20.
N. Jayaprakash N. Kalaiselvi C. H. Doh Gangulibabu D. Bhuvaneswari 《Journal of Applied Electrochemistry》2010,40(12):2193-2202
A series of LiM1xM2yMn2−x−yO3.8F0.2 (M1 = Cr, M2 = V; x = y = 0.2) cathodes, viz., LiMn2O3.8F0.2, LiCr0.2Mn1.8O3.8F0.2 and LiCr0.2V0.2Mn1.6O3.8F0.2 along with native LiMn2O4 have been synthesized by Citric Acid assisted Modified (CAM) sol–gel method, with a view to understand the effect of synthesis
methodology and the effect of dual category dopants, viz., anion and/or cation upon spinel cathodes individually. An acceptable
capacity retention (94%) observed up to 50 cycles for native LiMn2O4 cathodes is attributed to the significance of CAM sol–gel method. Similarly, the encouraging charge–discharge results of
LiMn2O3.8F0.2 (130 mAh g−1) and LiCr0.2Mn1.8O3.8F0.2 (142 mAh g−1) cathodes revealed a possible augmentation in the reversible capacity behavior of the spinels upon F− substitution at 32e site and the simultaneous substitution of Cr3+ and F− at 16d and 32e sites respectively. 相似文献