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991.
I. Schmelzer 《Annalen der Physik》2011,523(7):576-579
Schulz claims to have constructed an actively local stochastic theory which violates Bell's inequality. This is false. 相似文献
992.
Jung-Ryul Lee See Yenn ChongChang-Yong Yun Dong-Jin Yoon 《Optics and Lasers in Engineering》2011,49(1):110-120
A fiber Bragg grating (FBG) sensor head, using a pressure coupling mechanism, was designed for broadband frequency response and structural strain-free characteristic. The pressure-coupled sensor heads were connected to a simultaneous multipoint acoustic sensing system based on a tunable laser. An intelligent lasing wavelength stabilization algorithm capable of identifying the direction of spectrum movement, the wavelength shifting speed, and a fiber bending event was developed so that the simultaneous multipoint acoustic sensing system could be used in environments with rapid temperature variations. The lasing wavelength feedback control algorithm updated the lasing wavelength into the steep slope of the FBG spectrum even under conditions of rapid temperature change. The averaging lasing wavelength updating time was only 21 s because the system can decide a minimal size in scan window by finding the FBG spectrum shifting speed and direction in real time. The system was able to update the lasing wavelength which missed the steep slope of the FBG spectrum under maximum temperature variation rates 0.3014 and −0.3246 °C/s. The proposed system detected simultaneous impact waves at multiple points under conditions of rapid temperature change and change in dynamic strain. 相似文献
993.
A. Khandual N. Rout S.K. Verma P. Patel P. Pattanaik Y. Luximon A. Kumar R.K. Nayak M. Suar 《Materials Today Chemistry》2020
The Nanoparticle (NP) and their oxides are being progressively used and expected to be more frequently used in textiles. Nanoparticle (NP) has higher toxicological risk than larger particles because of their physicochemical properties, chemical reactivity and biological activity. In fact, the stability of nano-oxide particles in the medium is always challenging as they lack functional groups to leverage upon textile materials directly. Thus, in many finishing processes, cross-linkers and/or adhesives are applied together with NP at the cost of inferior comfort, feel and fastness which tends to be toxic and prone to release NPs under common laundering, physical stress and sweat. This study shows that the diffusion of NPs into the fibre polymer matrix via dyeing technique could be much durable, safer in terms of cytotoxicity levels and easy to process for tailoring desired functional attributes. We studied the possibility of a simple application technique via dyeing of vinyl sulphone based reactive dye with four kinds of NPs followed by their cytotoxicity test using cell line A431.1% silica dyed sample have shown highest (198.5%) increase in tensile strength followed by 2% silica and 2% CNT whereas a decrease in elongation is highest in the case of CNT 2% (5.31%) and significantly enhancing the moisture management properties in case of CNT and silica. The study showed promising results in dyeing with TiO2, CNT (Carbon nanotubes), Silica and Alumina NPs in enhancing the mechanical, moisture management, and surface frictional properties to ensure comfortable and safe wear. 相似文献
994.
We analyse models for panel data that arise in risk allocation problems, when a given set of sources are the cause of an aggregate risk value. We focus on the modelling and forecasting of proportional contributions to risk over time. Compositional data methods are proposed and the time-series regression is flexible to incorporate external information from other variables. We guarantee that projected proportional contributions add up to 100%, and we introduce a method to generate confidence regions with the same restriction. An illustration is provided for risk capital allocations. 相似文献
995.
Pietro De Giovanni Salma Karray Guiomar Martín-Herrán 《European Journal of Operational Research》2019,272(2):465-480
Most of the cooperative advertising literature has focused on studying the effects of such programs considering marketing variables. This paper integrates production and inventory management with pricing and advertising considerations to assess the effects of cooperative advertising programs in bilateral monopolies. We consider a supply chain where a Vendor Managed Inventory (VMI) along with a consignment contract is implemented to coordinate the chain. We develop and solve a differential model for two games. The first one is a benchmark scenario where no cooperative advertising is offered, while the manufacturer offers the cooperative program in the second game. The main results show that cooperative advertising programs, usually considered as successful marketing initiatives, can be very difficult to implement in a supply chain undertaking a VMI policy with a consignment contract, in which operations and marketing interface is taken into account. A cooperative program mainly hurts the manufacturer’s profits, and can be profit-Pareto-improving only in a few cases. Although the retailer is generally willing to receive a support from the manufacturer, she can opt for a non-cooperative program when the largest part of the supply chain profits goes to the manufacturer. We developed several special cases to strengthen our findings. 相似文献
996.
Several leading manufacturers recently combined the traditional retail channel with a direct online channel to reach a wider range of customers. We examine such a dual-channel supply chain under price and delivery-time dependent stochastic customer demand. We consider five decision variables, the price and order quantity for both the retail and the online channels and the delivery time for the online channel. Uncertainty frequently arises in both retail and online channels and so additional inventory management is required to control shortage or overstock and that has an effect on the optimal order quantity, price, and lead time. We developed mathematical models with the profit maximization motive. We analyze both centralized and decentralized systems for unknown distribution function of the random variables through a distribution-free approach and also for known distribution function. We examine the effect of delivery lead time and customers’ channel preference on the optimal operation. For supply chain coordination a hybrid all-unit quantity discount along a franchise fee contract is used. Moreover, we use the generalized asymmetric Nash bargaining for surplus profit distribution. A numerical example illustrates the findings of the model and the managerial insights are summarized for centralized, decentralized, and coordinated scenarios. 相似文献
997.
Yantong Li Feng Chu Chengbin Chu Zhanguo Zhu 《European Journal of Operational Research》2019,272(3):914-927
A classic production routing problem (PRP), in which a plant produces and distributes a single product to a set of customers over a finite time horizon, consists of planning simultaneously the production, inventory and routing activities to minimize the total cost. The last few decades have witnessed the increasing efforts made to solve such a complex problem. In this paper, we investigate a generalized PRP by considering multiple products and outsourcing (MPRP-OS). The newly studied problem is first formulated into a mixed integer linear program. Then a three-level mathematical-programming-based heuristic called TLH is developed to solve it. TLH combines a two-phase iterative method, a repairing strategy and a fix-and-optimize procedure to find near-optimal solutions. In addition, it is adaptable to solve the classic PRP. Computational experiments on 225 newly generated MPRP-OS instances with up to 200 customers, 20 vehicles, 6 periods and 12 products show the effectiveness and efficiency of the proposed heuristic. The performance of TLH is further demonstrated by testing 1530 classic PRP benchmark instances with up to 200 customers, 13 vehicles and 20 periods. Experimental results indicate that TLH is able to solve large-sized MPRP-OS instances within short computation times. In addition, TLH provides new best solutions for 283 out of 1530 benchmark instances. 相似文献
998.
在由一个供应商和一个销售商组成的单期两级供应链中,处于主导地位的销售商以其卖场所具有的销售能力参与供应链合作,并从销售的每一个产品中获取既定收益。同时,销售商还向供应商出售建立在产品销售量保障基础上的看跌期权,以激励供应商参与供应链合作。论文对上述情形的销售商出售看跌期权的供应链合作问题进行了研究,通过建模与优化分析,证明了在销售商提供看跌期权的供应链合作中,供应商存在唯一的最优生产批量和看跌期权采购量,以及销售商存在最优的从每一单位产品销售中获取的既定收益。论文还揭示了销售商提供看跌期权,虽然无法实现供应链协调,但可以实现供应链参与企业所获得的收益与其所承担的风险相匹配。最后,论文论证了在销售商出售看跌期权机制下,供应链存在收益损失较小的理想合作区域。 相似文献
999.
Multistate transition models are increasingly used in credit risk applications as they allow us to quantify the evolution of the process among different states. If the process is Markov, analysis and prediction are substantially simpler, so analysts would like to use these models if they are applicable. In this paper, we develop a procedure for assessing the Markov hypothesis and discuss different ways of implementing the test procedure. One issue when sample size is large is that the statistical test procedures will detect even small deviations from the Markov model when these differences are not of practical interest. To address this problem, we propose an approach to formulate and test the null hypothesis of “weak non‐Markov.” The situation where the transition probabilities are heterogeneous is also examined, and approaches to accommodate this case are indicated. Simulation studies are used extensively to study the properties of the procedures, and two applications are to illustrate the results. 相似文献
1000.
Vladimír Kočí Martin Mlejnek Lucie Kochánková 《Central European Journal of Chemistry》2003,1(1):28-34
This article is focused on bioassay evaluation of exposed SPMDs. Toxicity testing of SPMD extract is a suitable complementary
parameter to chemical analysis. Vtox as an integrative parameter describing toxic properties of extract from membrane and thus a level of contamination of assessed
ambient is presented here. Two examples of practical use of Vtox is demonstrated: a course of toxicity throw wastewater treatment plant with industrial inlets and increase of toxicity in
surface water body caused by leakages of POPs from industrial plant. 相似文献