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71.
Dong Won Cho Young Hae Lee Tae Youn Lee Mitsuo Gen 《Journal of Intelligent Manufacturing》2014,25(5):1025-1042
In this paper we propose an adaptive genetic algorithm that produces good quality solutions to the time dependent inventory routing problem (TDIRP) in which inventory control and time dependent vehicle routing decisions for a set of retailers are made simultaneously over a specific planning horizon. This work is motivated by the effect of dynamic traffic conditions in an urban context and the resulting inventory and transportation costs. We provide a mixed integer programming formulation for TDIRP. Since finding the optimal solutions for TDIRP is a NP-hard problem, an adaptive genetic algorithm is applied. We develop new genetic representation and design suitable crossover and mutation operators for the improvement phase. We use adaptive genetic operator proposed by Yun and Gen (Fuzzy Optim Decis Mak 2(2):161–175, 2003) for the automatic setting of the genetic parameter values. The comparison of results shows the significance of the designed AGA and demonstrates the capability of reaching solutions within 0.5 % of the optimum on sets of test problems. 相似文献
72.
Gwang-Suk You Ji-Whan Ahn Gi-Chun Han Hee-Chan Cho 《Korean Journal of Chemical Engineering》2006,23(2):237-240
This study measures the neutralizing capacity of bottom ash from municipal solid waste incineration of different particle
sizes. We examine the effect of particle size on the weathering process, a method popularly used for stabilization of heavy
metals in incineration of bottom ash. The distribution of particle sizes in municipal solid waste incineration bottom ash
is rather broad, ranging from fine powder to as large as 40 mm in diameter. Although considered a by-product highly suitable
as a road construction material, the high level of heavy metal leaching is an obstacle to its reuse. Weathering, a method
used to reduce heavy metal leaching, is a lengthy process taking over thee months to complete. The chief reaction involved
in weathering is carbonation occurring between Ca(OH)2 in bottom ash and CO2(g) in the atmosphere. During this process, CaCO3 is produced, causing the pH level to drop from over 12 to about 8.2 and reducing heavy metal leaching. In this paper, we
attempt to determine the particle size best suited for reducing the period required for weathering bottom ash by identifying
characteristics of different particle sizes that affect heavy metal leaching and neutralization. 相似文献
73.
Pd catalysts supported on TiO2, ZrO2, ZSM-5, MCM-41 and activated carbon were used in catalytic wet oxidation of hydrocarbons such as phenol, m-cresol and m-xylene.
It was found that the Pd/TiO2 catalyst was highly effective in the wet oxidation of hydrocarbon. The activities of catalysts with various hydrocarbon species,
catalyst support, oxidation state of catalyst performed in a 3-phase slurry reactor show that reaction on Pd surface is more
favorable than that in aqueous phase and that the active site is oxidized Pd in catalytic wet air oxidation of hydrocarbons.
Based on the experimental results, a plausible reaction mechanism of wet oxidation of hydrocarbons catalyzed over Pd/TiO2 catalyst was proposed. This catalyst is superior to other oxide catalysts because it suppressed the formation of hardly-degradable
organic intermediates and polymer. 相似文献
74.
Won-Ho Lee Hyoun-Ee Kim Seong-Jai Cho 《Journal of the American Ceramic Society》1997,80(10):2737-2740
Microstructural evolution of gas-pressure-sintered Si3 N4 with Yb2 O3 as a sintering aid was observed. Microstructures typical for in situ toughened Si3 N4 , i.e., large elongated grains randomly distributed in a fine matrix, were observed. However, the size of the elongated grains near the surface was much larger than that at the center, resulting in two distinct regions: an inner region and an outer region. The smaller the amount of Yb2 O3 added, the larger the difference in the size of the elongated grains between the outer and inner regions. The difference between microstructures was diminished when 16 wt% Yb2 O3 was added. The microstructural change with Yb2 O3 content was attributed to the evaporation of Yb-containing liquid phase from the surface. 相似文献
75.
Hyeon Gyu Kim Yoo Hyun Park Yang Hyun Cho Myoung Ho Kim 《Journal of Intelligent Information Systems》2014,43(2):323-347
The join is an important operator in processing data streams. To produce outputs continuously over unbounded data streams, sliding windows are generally used to limit the scope of the join at a certain time. In the existing join algorithms, only a simple type of windows have been considered, which are updated whenever a new data item arrives on any input stream. On the other hand, a more common type of windows have not been addressed yet, whose intervals are updated periodically, i.e., slid by a predefined time interval. In this paper, we consider the time-slide windows in joining multiple data streams. The algorithm for the time-slide window join can vary according to (i) how frequently the join is evaluated and (ii) which structure is used for windowing. Regarding this, possible algorithms are discussed, and experimental results that compare their performances are provided in this paper. 相似文献
76.
Fault identification for process monitoring using kernel principal component analysis 总被引:2,自引:0,他引:2
In this research, we develop a new fault identification method for kernel principal component analysis (kernel PCA). Although it has been proved that kernel PCA is superior to linear PCA for fault detection, the fault identification method theoretically derived from the kernel PCA has not been found anywhere. Using the gradient of kernel function, we define two new statistics which represent the contribution of each variable to the monitoring statistics, Hotelling's T2and squared prediction error (SPE) of kernel PCA, respectively. The proposed statistics which have similar concept to contributions in linear PCA are directly derived from the mathematical formulation of kernel PCA and thus they are straightforward to understand. The main contribution of this work is that we firstly suggest a fault identification method especially applicable to process monitoring using kernel PCA. To demonstrate the performance, the proposed method is applied to two simulated processes, one is a simple nonlinear process and the other is a non-isothermal CSTR process. The simulation results show that the proposed method effectively identifies the source of various types of faults. 相似文献
77.
The onset of thermal convection in a translucent porous layer is considered. Attention is focused on the effect of radiative heat transfer on the critical Rayleigh-Darcy number and the convection cell shape. If we consider the contribution of radiative heat transfer, the basic temperature profile is non-linear and the thermal convective instability is influenced by the ratio of conduction to radiation heat flux, the temperatures at the boundary surfaces, and radiative parameters such as wall emissivity, scattering albedo and extinction coefficient as well as the usual Rayleigh-Darcy number. Effects of these parameters on the onset of convective instability are investigated with the help of linear stability theory employing the Darcy's law and the radiative transport equation simplified by the P1 approximation. The increased effective thermal conductivity due lo the radiation inhibits the onset of convection and causes increased critical Rayleigh-Darcy number and decreased convection cell size. The results of the present work may be exploited to find out the optimal diameter of aerogel pellets and the air pressure in the double pane window filled with the translucent silica aerogel granules to suppress natural convection. 相似文献
78.
The farnesoid X receptor (FXR, NR1H4) has been recognized as an attractive therapeutic target because it is a nuclear hormone
receptor that controls the expression level of cholesterol-7α-hydroxylase, which in turn regulates bile acid production and
cholesterol excretion. To compare receptor activity between each domain and the full-length protein, human FXR cDNA was cloned
from a human liver cDNA library. Three human FXR cDNA, designated FXR20, FXR33, and FXR53 cDNA, were subcloned and ligated into a pET28a expression vector. Each protein was expressed in Escherichia coli (BL21) and purified by nickel-nitrilotriacetic acid column chromatography. Approximately 5 mg of FXR33 (1–182 amino acids deleted from FXR, 37 kDa) and 2 mg of FXR53 (the full-length protein of FXR, 59 kDa) was purified from 1 L of Luria-Bertani culture, achieving at least 90% purity. The
coactivator recruitment assay for FXR activation was carried out with the three variants of the FXR protein by using dissociation-enhanced
lanthanide fluoroimmunoassay-europium-N1-labeled anti-His antibody. From an optimized assay, a saturated hyperbolic fluorescence signal curve was produced when 250
nM of FXR33 and 100 nM of steroid receptor coactivator-1 peptide, a coactivator of FXR consisting of 26 amino acids, were used with a
concentration dependence on chenodeoxycholic acid (from 0 to 200 μM). The ligand-binding domain of FXR (FXR33) was the most suitable protein for studying the activation of FXR with a fluorescence-based assay, because it showed better
structural stability than either the full length of FXR (FXR53) or the DNA-binding domain of FXR (FXR20). 相似文献
79.
Sung‐Jun Cho 《应用聚合物科学杂志》2003,88(8):1904-1910
The polymerization of ?‐caprolactam between the interlamellar spaces of the [TEACOOH]–montmorillonite intercalations complex was attempted using Na–montmorillonite and 10‐carboxy‐n‐decyltriethylammonium bromide to achieve [TEACOOH]–polycaprolactam–montmorillonite, in which montmorillonite (inorganic polymer) is chemically bonded with the polycaprolactam (organic polymer). The results of X‐ray and IR analysis for the samples obtained after polymerization showed that the polymerization reaction has been successfully accomplished. For the purpose of studying the polymeric reaction product more precisely, we have isolated the polymerized product from the silicate layers and analyzed it with X‐ray diffractometer and IR spectrometer. Comparison of the results of X‐ray and IR analysis between the isolated polymer and the polymer that was synthesized by the reaction of ?‐caprolactam only with the organic cation without montmorillonite showed that both obtained polymers are the same compounds. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1904–1910, 2003 相似文献
80.
Neung‐Ju Lee Ja‐Chul Koo Sung‐Suk Ju Seong‐Bae Moon Won‐Jei Cho In‐Cheol Jeong Song‐Jae Lee Moo‐Youn Cho Emmanuel A Theodorakis 《Polymer International》2002,51(7):569-576
The attachment of anticancer agents to polymers is a promising approach towards reducing the toxic side‐effects and retaining the potent antitumour activity of these agents. A new tetrahydrophthalimido monomer containing 5‐fluorouracil (ETPFU) and its homopolymer and copolymers with acrylic acid (AA) and with vinyl acetate (VAc) have been synthesized and spectroscopically characterized. The ETPFU contents in poly(ETPFU‐co‐AA) and poly(ETPFU‐co‐VAc) obtained by elemental analysis were 21 mol% and 20 mol%, respectively. The average molecular weights of the polymers determined by gel permeation chromatography were as follows: Mn = 8900 g mol?1, Mw = 13 300 g mol?1, Mw/Mn = 1.5 for poly(ETPFU); Mn = 13 500 g mol?1, Mw = 16 600 g mol?1, Mw/Mn = 1.2 for poly(ETPFU‐co‐AA); Mn = 8300 g mol?1, Mw = 11 600 g mol?1, Mw/Mn = 1.4 poly(ETPFU‐co‐VAc). The in vitro cytotoxicity of the compounds against FM3A and U937 cancer cell lines increased in the following order: ETPFU > 5‐FU > poly(ETPFU) > poly(ETPFU‐co‐AA) > poly(ETPFU‐co‐VAc). The in vivo antitumour activities of all the polymers in Balb/C mice bearing the sarcoma 180 tumour cell line were greater than those of 5‐FU and monomer at the highest dose (800 mg kg?1). © 2002 Society of Chemical Industry 相似文献