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991.
This research addresses the problem of designing a LTL logistics network over individual lanes by offering different delivery services (1-day, 2-day, 3-day). A network design is proposed which links lane-specific delivery service choices and service profitability to the hub location-allocation decisions. A hybrid-heuristic is developed which uses a search interval reduction technique with a meta-heuristic. The performance of the hybrid-heuristic is evaluated in a computational study. A factorial experiment design with real world data is used to analyze the network structure, service choices and shipment flows, which results in managerial insights about the design and operation of a LTL logistics network with differentiated services. 相似文献
992.
Many natural structures can be naturally represented by complex networks. Discovering network motifs, which are overrepresented patterns of inter-connections, is a computationally hard task related to graph isomorphism. Sequential methods are hindered by an exponential execution time growth when we increase the size of motifs and networks. In this article we study the opportunities for parallelism in existing methods and propose new parallel strategies that adapt and extend one of the most efficient serial methods known from the Fanmod tool. We propose both a master–worker strategy and one with distributed control, in which we employ a randomized receiver initiated methodology capable of providing dynamic load balancing during the whole computation process. Our strategies are capable of dealing both with exact and approximate network motif discovery. We implement and apply our algorithms to a set of representative networks and examine their scalability up to 128 processing cores. We obtain almost linear speedups, showcasing the efficiency of our proposed approach and are able to reach motif sizes that were not previously achievable using conventional serial algorithms. 相似文献
993.
Tatt Hee Oong Author VitaeNor Ashidi Mat IsaAuthor Vitae 《Applied Soft Computing》2012,12(4):1303-1308
This paper presents a new method called one-against-all ensemble for solving multiclass pattern classification problems. The proposed method incorporates a neural network ensemble into the one-against-all method to improve the generalization performance of the classifier. The experimental results show that the proposed method can reduce the uncertainty of the decision and it is comparable to the other widely used methods. 相似文献
994.
该设计采用人体红外传感器作为人体信号采集装置,利用光敏电阻准确判断光强信息,智能方便的设计为老年人提供更为人性化的服务。 相似文献
995.
M. Erdem Günay Fatma AkpinarZ. Ilsen Onsan Ramazan Yildirim 《International Journal of Hydrogen Energy》2012
The water gas shift activity of promoted Pt–CeO2/Al2O3 catalysts were investigated in this work. The catalysts were prepared by incipient to wetness impregnation and tested using a microflow reaction system. It was found that K has beneficial effects under product-containing feed compositions while Co and Ni promoters worsen catalyst performance. The reaction temperature and feed H2O/CO ratio positively affect the catalytic activity, whereas CO2 and H2 addition to the feed decreases CO conversion, as expected. The experimental results were also modeled using modular neural networks, at which the catalyst preparation and operational (reaction) variables were used together in the same network because they are interacting but processed differently because they are dissimilar in their form (i.e. categorical versus continuous) and their effects on catalytic activity. It was concluded that the effects of catalyst preparation and operational variables and their relative importance could be comprehended more accurately by using this approach, which may be also employed in other similar systems. 相似文献
996.
《国际聚合物材料杂志》2012,61(16):838-847
A fluorescent textile sensor and its capacities to detect pH changes in aqueous solutions have been reported. A new hydrogel-cotton fabric was obtained via surface initiated photopolymerization of 2-aminoethylmethacrylate hydrochloride, with N,N′-methylene-bis-acrylamide as a crosslinker, and fluorophore and modified eosin Y and N-methyldiethanolamine as photoinitiators. The synthesis of the modified eosin Y and a new 1,8-naphtalimide used as signal units in the hydrogel composite have been described. It has been found that the concentration of the photoinitiator affects the functional properties of the composite. pH variations influence the gel structure and this is transduced into fluorescence and color changes of the material. 相似文献
997.
A Strong Anti-Jamming Algorithm Based on FPGA for Estimating Loop Delay in Digital Predistortion System 下载免费PDF全文
Feng-Jun Li Jing-Fu Bao Hong-Yun Huang Shao-Chun Jin 《电子科技学刊:英文版》2012,10(4):358-362
At present what are the key points focused in the research of loop-delay estimation for the digital predistorter in the radio frequency (RF) power amplifier system is reducing its complexity of engineering realization and improving anti-jamming ability and computational speed. Besides, opening up its application scope should be contained. For these targets, a novel method including integer loop delay estimation and fractional part is proposed. The integer part applies amplitude-difference summation function and the fractional one adopts the method of finite impulse response (FIR) linear interpolation. The algorithm finds wide applications. What is more, strong anti-jamming ability and low complexity are also its merits. Simulation results support the above opinion. Digital predistortion (DPD) system based on this algorithm achieves good performance. 相似文献
998.
针对板坯连铸机结晶器振动纵向横向偏摆问题,对结晶器振动装置应用情况进行研究分析,用硬度仪打硬度的方法分析了辊子单元导向的磨损情况。使用新型棍子材质并经热处理代替原进口辊子本体,重新改进润滑油路,采用更适应高温高湿环境的不锈钢内六角螺栓,重新设计制作了一种耐磨长寿命辊子单元,在线使用效果显示使用寿命已经达到18个月且仍然完好,偏摆问题得到纠正,达到预期目的。 相似文献
999.
Simon von Danwitz 《International Journal of Project Management》2018,36(3):525-541
Although the management of inter-firm projects is increasingly being researched in a wide range of academic fields (project management, alliances and networks, organization studies), the findings of these studies rarely cross theoretical boundaries. In the present study, a systematic literature review of 219 contributions from 26 years of academic research on managing inter-firm projects identifies 22 key management issues underlying its contributions. Based on a two-dimensional framework (project stage and analytical sphere), a structured and integrative synthesis of relevant studies is outlined. Based on these findings, future investigations are proposed to focus on dynamic, contextual and structural aspects of the management of inter-firm projects. 相似文献
1000.
Martina Hübner Gerrit Dumstorff Maryam Kahali Mogaddam Peter Plagemann Walter Lang 《Journal of Adhesion Science and Technology》2018,32(7):772-786
Monitoring adhesives during manufacturing and their lifetime has become increasingly important due to the variety of materials and applications. Impedance spectroscopy is a suitable method for online monitoring of the curing process. We present a miniaturised interdigital structure to monitor the curing process of the adhesives using impedance spectroscopy. Compared to other sensors, our sensor is ultrathin, so that it disappears in the adhesive joint. Therefore, it can remain in the joint and be used for lifetime monitoring. In addition it is suitable for thin adhesive layers due to its fine grid. We demonstrate that the impedance of the sensor embedded in the adhesive gives insight into the curing mechanisms. Therefore monitoring of a dispersion and an epoxy is shown. In addition, the curing cycles can be reliably controlled using this monitoring method. The permittivity of the adhesives is extracted from the impedance measurements, applying analytical models of the electrical field of the interdigital structure. 相似文献