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91.
For dynamic scheduling of multi-class systems where backorder cost is incurred per unit backordered regardless of the time
needed to satisfy backordered demand, the following models are considered: the cost model to minimize the sum of expected
average inventory holding and backorder costs and the service model to minimize expected average inventory holding cost under
an aggregate fill rate constraint. Use of aggregate fill rate constraint in the service model instead of an individual fill
rate constraint for each class is justified by deriving equivalence relations between the considered cost and service models.
Based on the numerical investigation that the optimal policy for the cost model is a base-stock policy with switching curves
and fixed base-stock levels, an alternative service model is considered over the class of base-stock controlled dynamic scheduling
policies to minimize the total inventory (base-stock) investment under an aggregate fill rate constraint. The policy that
solves this alternative model is proposed as an approximation of the optimal policy of the original cost and the equivalent
service models. Very accurate heuristics are devised to approximate the proposed policy for given base-stock levels. Comparison
with base-stock controlled First
Come
First
Served (FCFS) and Longest
Queue (LQ) policies and an extension of LQ policy (Δ policy) shows that the proposed policy performs much better to solve the service models under consideration, especially
when the traffic intensity is high. 相似文献
92.
Zeynep Serinyel Guillaume Dayma Valentin Glasziou Maxence Lailliau Philippe Dagaut 《Proceedings of the Combustion Institute》2021,38(1):329-336
Pyrolysis of diethyl (C4), di-n-propyl (C6), di-isopropyl (C6) and di-n-butyl (C8) ethers were studied in a jet-stirred reactor between 720 and 1140 K, at 10 atm with an initial ether mole fraction of 0.1%. Major common pyrolysis products were observed to be CO, CH4, H2, and C2H4. All ethers produced the n/2 alcohol and olefin as products of molecular reaction to a small extent. Under pyrolysis conditions at 10 atm, hydrogen abstraction reactions by H atoms and CH3 radicals were found to be important. Acetylene and benzene were formed for all ethers when T > 1000 K. A kinetic mechanism is used to represent these results. This study shows that there is need of systematic studies in determining site specific rate constants of important fuel related reactions of ethers. 相似文献
93.
The basic aim of this work is to design a new tridiagonal matrix enhanced multivariance products representation (TMEMPR) which uses not Cartesian vectors but matrices as the support entities. What we obtain after the construction of the representation has been a singular value decomposition like structure where the core matrix becomes a block tridiagonal matrix in contrast to the diagonal and tridiagonal matrix structures of the singular value decomposition of matrices and TMEMPR respectively. We have used support matrices in the construction and not directly orthogonality of the constructed support matrices but block orthogonality which means the mutual ortho normality of the columns of produced support matrices. Certain confirmative implementations finalize the paper. 相似文献
94.
95.
Zeynep Demircioğlu Çiğdem Albayrak Kaştaş Orhan Büyükgüngör 《Molecular Crystals and Liquid Crystals》2017,656(1):169-184
The title compound was isolated and investigated by experimental X-ray diffraction method and density functional theory (DFT) calculational properties and spectroscopic methodologies. The experimental investigations of the compound indicated the molecule seems to be in enol form. DFT calculations are performed both for enol and keto tautomers of the title compound. Additionally chemical activity, electronic transmission and property effect on different solvents, molecular electrostatic potential (MEP), non-linear optical properties (NLO), Mulliken population method, natural population analysis (NPA), natural bond orbital (NBO) and Fukui function analyses have been studied. 相似文献
96.
R. Branzei O. Branzei S. Zeynep Alparslan Gök S. Tijs 《Central European Journal of Operations Research》2010,18(3):397-411
The (re)distribution of collective gains and costs is a central question for individuals and organizations contemplating cooperation under uncertainty. The theory of cooperative interval games provides a new game theoretical angle and suitable tools for answering this question. This survey aims to briefly present the state-of-the-art in this young field of research, discusses how the model of cooperative interval games extends the cooperative game theory literature, and reviews its existing and potential applications in economic and operations research situations with interval data. 相似文献
97.
Psatha EA Hyslop WB Woosley JT Firat Z Bilaj F Semelka RC 《Magnetic resonance imaging》2004,22(7):1053-1057
We report the magnetic resonance (MR) appearance of a large B-cell lymphoma in the peripancreatic head region, in a 38-year-old male who presented with a 1-month history of pruritus and jaundice. Routine laboratory examination at presentation revealed an elevated bilirubin. The tumor was a large, solitary well-defined mass with no evidence of necrosis, which showed mild diffuse heterogeneous enhancement. The tumor was closely applied to the lateral margin of the head of the pancreas. The constellation of MR findings was interpreted as consistent with the correct eventual diagnosis of lymphoma. 相似文献
98.
Synthesis of chalcone‐containing methacrylate‐based hydrogen bonded side chain liquid crystalline polymer and its dielectric properties 下载免费PDF全文
Burak Korkmaz Yesim Hepuzer Gursel Nimet Yilmaz Canli Zeynep Güven Özdemir Mustafa Okutan Bahire Filiz Senkal 《先进技术聚合物》2017,28(11):1351-1356
In this work, a new methacrylate‐based hydrogen bonded side chain liquid crystalline polymer having chalcone moieties (HBCP) was prepared from poly(4‐(3‐(pyridin‐4‐yl)acryloyl) phenyl methacrylate) and 11‐(4‐cyanobiphenyl‐4(‐oxy) undekan‐1‐ol (LC11)) by molecular self‐assembly processes via hydrogen bond formation between nitrogen of the HBCP and hydroxyl group of the LC11. The formation of H bond was confirmed by using Fourier transform infrared (FTIR) spectroscopy. The phase transition temperatures and liquid crystalline phases of the HBCP were examined by DSC and POM measurements. The dielectric properties of HBCP have been determined by impedance analyzer within the frequency interval of 100 Hz–15 MHz. According to Cole–Cole plot, the equivalent circuit of the LC system has been found as a capacitor in parallel with a resistor. The resonance frequency, fr, of the R–C circuit has also been calculated as 1.59 MHz by phase angle versus frequency curve. The dielectric relaxation type of HBCP has been determined as nearly‐Debye type because the absorption coefficient, α, equals to 0.01655. From the conductivity point of view, HBCP displays dc conductivity at the low and high frequency regions that correspond to 100 Hz–12 kHz and 3.3 MHz–15 MHz, respectively. On the other hand, it has been revealed that the ac conductivity of the LC system investigated obeys Super Linear Power Law (SLPL) at the intermediate frequency domain. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
99.
Molecularly Imprinted Polymer Nanomaterials and Nanocomposites: Atom‐Transfer Radical Polymerization with Acidic Monomers 下载免费PDF全文
Zeynep Adali‐Kaya Dr. Bernadette Tse Sum Bui Dr. Aude Falcimaigne‐Cordin Prof. Karsten Haupt 《Angewandte Chemie (International ed. in English)》2015,54(17):5192-5195
Molecularly imprinted polymers (MIPs) are artificial receptors which can be tailored to bind target molecules specifically. A new method, using photoinitiated atom‐transfer radical polymerization (ATRP) for their synthesis as monoliths, thin films and nanoparticles is described. The synthesis takes place at room temperature and is compatible with acidic monomers, two major limitations for the use of ATRP with MIPs. The method has been validated with MIPs specific for the drugs testosterone and S‐propranolol. This study considerably widens the range of functional monomers and thus molecular templates which can be used when MIPs are synthesized by ATRP, as well as the range of physical forms of these antibody mimics, in particular films and lithographic patterns, and their post‐functionalization from living chain‐ends. 相似文献
100.
Photo‐ and thermal‐polymerizations of 4‐diethoxyphosphoryl‐2,4,6‐tris(ethoxycarbonyl)‐1,6‐heptadiene, 4,4‐bis(diethoxyphosphoryl)‐2,6‐bis(t‐butoxycarbonyl)‐1,6‐heptadiene and 4‐diethoxyphosphoryl‐4‐ethoxycarbonyl‐2,6‐bis(t‐butoxycarbonyl)‐1,6‐heptadiene monomers and their phosphonic and carboxylic acid derivatives were investigated to understand the effect of the cyclic monomer structure on their polymerization reactivity. A strong effect of the substituents at positions 2, 4 and 6 of the monomers on polymerization rate was observed. The polymerizability of the monomers was successfully correlated with the 13C NMR chemical shifts of the vinyl carbons. Conversion values were consistent with the Tg being a measure of the flexibility of a monomer. The monomers containing phosphonic acid groups were soluble in water and ethanol. The acidic nature of the aqueous solutions of these monomers is expected to give them etching properties, important for dental applications. The interaction of the acid monomers with hydroxyapatite was investigated using 13C NMR technique.