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- 1
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- Optimization model for the new coordinated replenishment and delivery problem with multi-warehouse
- [期刊] , 2017, 28(2): 290-310 SSCI Scopus
- 被引用 3 (Web of Science℠)
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摘要Purpose - The purpose of this paper is to investigate a new and practical decision support model of the coordinated replenishment and delivery (CRD) problem with multi-warehouse (M-CRD) to improve the performance of a supply chain. Two algorithms, tabu search-RAND (TS-RAND) and adaptive hybrid different evolution (AHDE) algorithm, are developed and compared as to the performance of each in solving the M-CRD problem. Design/methodology/approach - The proposed M-CRD is more complex and practical than classical CRDs, which are non-deterministic polynomial-time hard problems. According to the structure of the M-CRD, a hybrid algorithm, TS-RAND, and AHDE are designed to solve the M-CRD. Findings - Results of M-CRDs with different scales show that TS-RAND and AHDE are good candidates for handling small-scale M-CRD. TS-RAND can also find satisfactory solutions for large-scale M-CRDs. The total cost (TC) of M-CRD is apparently lower than that of a CRD with a single warehouse. Moreover, the TC is lower for the M-CRD with a larger number of optional warehouses. Originality/value - Compared with the traditional CRDs with one warehouse, a better policy with lower TC can be obtained by the new M-CRD. Moreover, the proposed TS-RAND is a good candidate for solving the M-CRD.关键词Transportation management , Purchasing , Supply chain management , TS-RAND algorithm , Hybrid different evolution algorithm , Decision making
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- Composition and size distribution of airborne particulate PAHs and oxygenated PAHs in two Chinese megacities
- [期刊] , 2017, 183(): 322-330 EI SCIE Scopus
- 被引用 8 (Web of Science℠)
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摘要Concentrations and compositions of PAHs and oxygenated PAHs (OPAHs) in four size ranges of ambient particles (<1.1, 1.1-3.3, 33-9.0 and >9.0 mu m) collected in Xi'an and Guangzhou, two megacities of China, during the winter and summer of 2013 were measured and compared with those in 2003. The TSP-equivalent concentrations of Sigma 14PAHs in Xi'an and Guangzhou are 57 +/- 20 and 18 +/- 23 ng m(-3) in winter, 5-10 times higher than those in summer. PAHs in both cities are dominated by 5- and 6-ring congeners in summer. In contrast, they are dominated by 4- and 5-ring congeners in winter, probably due to enhanced gas-to-particle phase partitioning of the semi-volatile PAHs. TSP-equivalent Sigma OPAHs during winter are 54 +/- 15 and 23 +/- 32 ng m(-3) in Xi'an and Guangzhou and dominated by 5-ring OPAHs. Size distribution results showed that the fine modes (<33 mu m) of PAHs and OPAHs in both cities are dominated by 4- and 5-ring congeners in winter and 5- and 6-ring congeners in summer. Relative abundances of 3-ring PAHs and OPAHs increased along with an increase in particle sizes, accounting for from about 1% of the total PAHs or OPAHs in the smallest particles (<1.1 mu m) to >90% of the total in the largest particles (>9.0 mu m). The toxicity of PAH assessment indicated that atmospheric particles in Xi'an and Guangzhou during winter are much more toxic than those during summer and fine particles are more toxic than coarse particles. Compared to those in 2003, fine particulate PAHs and OPAHs in both cities during winter decreased by 50-90%, most likely due to the replacement of coal by natural gas in the country. (C) 2016 Elsevier B.V. All rights reserved.关键词Source and formation , Historical comparison , Toxicity , Molecular composition , Size distribution
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- The concept and progress of intelligent spindles: A review
- [期刊] , 2017, 112(): 21-52 EI SCIE Scopus
- 被引用 18 (Web of Science℠)
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摘要Intelligent spindles are core components of the next-generation of intelligent/smart machine tools in the Industry 4.0 Era. The purpose of this paper is to clarify the concept of intelligent spindles and provide an in-depth review of the state-of-the-art of related technologies. A new integrated concept for intelligent spindles is proposed, followed by descriptions of required characteristics, key enabling technologies and expected intelligent functions. Relevant research that may be beneficial to the development of intelligent spindles is reviewed from six thrust areas, which include monitoring and control of tool condition, chatter, spindle collision, temperature/thermal error, spindle balance, and spindle health. Finally, current limitations and challenges are discussed, and future trends of intelligent spindles are prospected from various perspectives.关键词Control , Machine tools , Machining process , Intelligent spindles , Condition monitoring
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- Strength and plasticity of nanolaminated materials
- [期刊] , 2017, 5(1): 1-19 Scopus SCIE
- 被引用 0 (Web of Science℠)
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摘要© 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.The mechanical behavior of nanolaminates is dominated by interfaces that act as sources, barriers, and preferred sites for storage and dynamic recovery of glide dislocations. In this article, the deformation mechanisms of a variety of metal-based nanolaminates are reviewed with emphasis on unusual mechanical properties such as ultra-high flow strength without loss of plastic deformability.关键词dislocations | interfaces | Nanolaminate | plasticity | strength
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- The Multifaceted Role of SNARE Proteins in Membrane Fusion
- [期刊] , 2017, 8(): SCIE Scopus
- 被引用 13 (Web of Science℠)
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摘要Membrane fusion is a key process in all living organisms that contributes to a variety of biological processes including viral infection, cell fertilization, as well as intracellular transport, and neurotransmitter release. In particular, the various membrane-enclosed compartments in eukaryotic cells need to exchange their contents and communicate across membranes. Efficient and controllable fusion of biological membranes is known to be driven by cooperative action of SNARE proteins, which constitute the central components of the eukaryotic fusion machinery responsible for fusion of synaptic vesicles with the plasma membrane. During exocytosis, vesicle-associated v-SNARE (synaptobrevin) and target cell-associated t-SNAREs (syntaxin and SNAP-25) assemble into a core trans-SNARE complex. This complex plays a versatile role at various stages of exocytosis ranging from the priming to fusion pore formation and expansion, finally resulting in the release or exchange of the vesicle content. This review summarizes current knowledge on the intricate molecular mechanisms underlying exocytosis triggered and catalyzed by SNARE proteins. Particular attention is given to the function of the peptidic SNARE membrane anchors and the role of SNARE-lipid interactions in fusion. Moreover, the regulatory mechanisms by synaptic auxiliary proteins in SNARE driven membrane fusion are briefly outlined.关键词synaptobrevin , fusion regulation , protein-lipid interactions , syntaxin , membrane fusion , SNAP-25 , SNARE
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- Review of methodologies and polices for evaluation of energy efficiency in high energy-consuming industry
- [期刊] , 2017, 187(): 203-215 EI SSCI SCIE Scopus
- 被引用 23 (Web of Science℠)
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摘要Energy efficiency of high energy-consuming industries plays a significant role in social sustainability, economic performance and environmental protection of any nation. In order to evaluate the energy efficiency and guide the sustainability development, various methodologies have been proposed for energy demand management and to measure the energy efficiency performance accurately in the past decades. A systematical review of these methodologies are conducted in the present paper. First, the classification of the industrial energy efficiency index has been summarized to track the previous application studies. The single measurement indicator and the composite index benchmarking are highly recognized as the modeling tools for power industries and policy-making in worldwide countries. They are the pivotal figures to convey the fundamental information in energy systems for improving the performance in fields such as economy, environment and technology. Second, the six factors that influence the energy efficiency in industry are discussed. Third, four major evaluation methodologies of energy efficiency are explained in detail, including stochastic frontier analysis, data envelopment analysis, exergy analysis and benchmarking comparison. The basic models and the developments of these methodologies are introduced. The recent utilization of these methodologies in the energy efficiency evaluations are illustrated. Some drawbacks of these methodologies are also discussed. Other related methods or influential indicators for measuring energy efficiency performance have also been presented. Finally, the related polices and suggestions based on the energy efficiency evaluations are provided. (C) 2016 Published by Elsevier Ltd.关键词Policy , Model , Energy efficiency evaluation , High energy-consuming industry
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- Mittag-Leffler stability of fractional-order neural networks in the presence of generalized piecewise constant arguments
- [期刊] , 2017, 85(): 118-127 EI SCIE Scopus
- 被引用 15 (Web of Science℠)
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摘要Neurodynamic system is an emerging research field. To understand the essential motivational representations of neural activity, neurodynamics is an important question in cognitive system research. This paper is to investigate Mittag-Leffler stability of a class of fractional-order neural networks in the presence of generalized piecewise constant arguments. To identify neural types of computational principles in mathematical and computational analysis, the existence and uniqueness of the solution of neurodynamic system is the first prerequisite. We prove that the existence and uniqueness of the solution of the network holds when some conditions are satisfied. In addition, self-active neurodynamic system demands stable internal dynamical states (equilibria). The main emphasis will be then on several sufficient conditions to guarantee a unique equilibrium point. Furthermore, to provide deeper explanations of neurodynamic process, Mittag-Leffler stability is studied in detail. The established results are based on the theories of fractional differential equation and differential equation with generalized piecewise constant arguments. The derived criteria improve and extend the existing related results. (C) 2016 Elsevier Ltd. All rights reserved.关键词Fractional-order systems , Generalized piecewise constant arguments , Mittag-Leffler stability , Neurodynamic systems
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- Transient response for a half-space with variable thermal conductivity and diffusivity under thermal and chemical shock
- [期刊] , 2017, 40(3): 389-401 EI Scopus SCIE
- 被引用 3 (Web of Science℠)
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摘要© 2017 Taylor & Francis.The present work aims to investigate the transient thermoelastic diffusive response for a half-space with variable thermal conductivity and diffusivity in the context of the generalized thermoelastic diffusion theory. The boundary plane of the half-space is assumed to be traction free and subjected to a time-dependent thermal and chemical shock. The governing equations of the problem are formulated by using Kirchhoff’s transformation. Due to the complexity of the equations, Laplace transformation method is applied to solve them. Numerical results are obtained and illustrated graphically. Parameter studies are performed to evaluate the effects of variable thermal conductivity and diffusivity on the response. The present investigation could be helpful for better understanding the multifield coupling effect of mechanical and thermal fields in real materials.关键词Generalized thermoelastic diffusion theory | Kirchhoff’s transformation | Laplace transform | variable diffusivity | variable thermal conductivity
- 9
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- Multiplexed instrument-free meningitis diagnosis on a polymer/paper hybrid microfluidic biochip
- [期刊] , 2017, 87(): 865-873 EI SCIE Scopus
- 被引用 0 (Web of Science℠)
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摘要Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae), and Haemophilus influenzae type b (Hib) are three most common pathogens accounting for most bacterial meningitis, a serious global infectious disease with high fatality, especially in developing nations. Because the treatment and antibiotics differ among each type, the identification of the exact bacteria causing the disease is vital. Herein, we report a polymer/paper hybrid microfluidic biochip integrated with loop-mediated isothermal amplification (LAMP) for multiplexed instrument-free diagnosis of these three major types of bacterial meningitis, with high sensitivity and specificity. Results can be visually observed by the naked eye or imaged by a smartphone camera under a portable UV light source. Without using any specialized laboratory instrument, the limits of detection of a few DNA copies per LAMP zone for N. meningitidis, S. pneumoniae and Hib were achieved within 1 h. In addition, these three types of microorganisms spiked in artificial cerebrospinal fluid (ACSF) were directly detected simultaneously, avoiding cumbersome sample preparation procedures in conventional methods. Compared with the paper-free non-hybrid microfluidic biochip over a period of three months, the hybrid microfluidic biochip was found to have a much longer shelf life. Hence, this rapid, instrument-free and highly sensitive microfluidic approach has great potential for point-of-care (POC) diagnosis of multiple infectious diseases simultaneously, especially in resource-limited settings.关键词Multiplexed meningitis diagnosis , Instrument-free detection , Low-resource settings , Hybrid microfluidic biochip , LAMP
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- Fourier spectral-based modal curvature analysis and its application to damage detection in beams
- [期刊] , 2017, 84(): 763-781 EI SCIE Scopus
- 被引用 11 (Web of Science℠)
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摘要In this paper, a simple Fourier spectral-based method is proposed to calculate the modal curvature (MC) of beams instead of the traditional central difference method. Based on the present method, damages in beam-like structures are localized. The present method provides an alternative selection to estimate MC in damage detection. There are two advantages of the present method. Firstly, the spectral calculation of spatial derivatives is conducted globally, which provides the suppression for noise. In addition, signal processing in the wavenumber domain provides an alternative choice for spatial filtering for mode shapes. Secondly, the proposed method provides a precise estimation of the MC which is related to original definition. With the absence of numerical derivative, the estimated results can be more stable and robust. Statistical analysis is conducted to show the effectiveness and noise immunity of the proposed method. In order to obtain the better identification, the MC calculated by the proposed method is employed as the input of continuous wavelet transform, and then the hybrid method is generated. The validations of the present method and comparison with the traditional central difference method are numerically and experimentally demonstrated. (C) 2016 Elsevier Ltd. All rights reserved.关键词Fourier transform , Wavenumber filtering , Modal curvature , Damage detection , Beam
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