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101.
Application of Petri Nets and a Genetic Algorithm to Multi-Mode Multi-Resource Constrained Project Scheduling 总被引:2,自引:0,他引:2
J. Prashant Reddy S. Kumanan O.V. Krishnaiah Chetty 《The International Journal of Advanced Manufacturing Technology》2001,17(4):305-314
Multi-mode and multi-resource constrained scheduling of a project is a complex task. This paper addresses the use of a Petri
net as a modelling and scheduling tool in this context. The benefits of Petri nets in project scheduling are discussed. We
propose extensions to Petri nets to suit scheduling of activities in a decision CPM. We also propose the use of a P-matrix
for token movements in Petri nets. A genetic algorithm is used to find a better solution. Petri-net-aided software including
genetic-algorithm-based search and heuristics is described to deal with a multi-mode, multi-constrained scheduling problem
with pre-emption of activities. 相似文献
102.
Minh Tam Hoang Amandeep Singh Pannu Yang Yang Sepideh Madani Paul Shaw Prashant Sonar Tuquabo Tesfamichael Hongxia Wang 《纳微快报(英文)》2022,(4):277-288
The remarkable evolution of metal halide perovskites in the past dec-ade makes them promise for next-generation optoelectronic material.In particular,nanocrysta... 相似文献
103.
The effect of rubber hardness on the properties of fiber‐reinforced plastic (FRP) composites is investigated in order to know the optimum composition of rubber mold used in rubber pressure molding (RPM) technique. A matching die set was used in RPM method, where the die was made of hard metal like steel and the punch from the flexible rubber like material, natural rubber. The use of flexible rubber punch generates and applies hydrostatic pressure on the surface of FRP composites. The hardness of rubber mold was controlled by incorporating carbon black as a filler material in the matrix of natural rubber and varied from 0 to 75 phr (per hundred rubber) in steps of 15 phr. Burn test, tension test, interlaminar shear test and interlaminar fracture toughness tests were conducted on the FRP composites to measure the void content, presence of delamination, tensile strength, inter laminar shear strength and inter laminar fracture toughness. The results are compared with the FRP composites made by conventional technique to evaluate the performance of RPM technique. It is observed that the laminates produced by RPM technique with different filler content in natural rubber mold show significant improvement in mechanical properties except interlaminar shear strength. POLYM. COMPOS., 28:618–630, 2007. © 2007 Society of Plastics Engineers 相似文献
104.
Thermal history of droplets associated with gas atomization of melt has been investigated. A mathematical model, based on
classical theory of heterogeneous nucleation and volume separation of nucleants among droplets size distribution, is described
to predict undercooling of droplets. Newtonian heat flow condition coupled with velocity dependent heat transfer coefficient
is used to obtain cooling rate before and after nucleation of droplets. The results indicate that temperature profile of droplets
in the spray during recalescence, segregated and eutectic solidification regimes is dependent on their size and related undercooling.
The interface temperature during solidification of undercooled droplets rapidly approaches the liquidus temperature of the
alloy with a subsequent decrease in solid-liquid interface velocity. A comparison in cooling rates of atomized powder particles
estimated from secondary dendrite arm spacing measurements are observed to be closer to those predicted from the model during
segregated solidification regime of large size droplets. 相似文献
105.
This paper presents the design and implementation of Ferret, a system for locating nomadic augmented with RFID tags and visually displaying them to a user in real-time. We present a novel algorithm to infer location of tagged objects using the location of a camera and reader that observes them. We also present techniques to refine location estimates using multiple observations and a method to display and update object locations on a video camera screen. An experimental evaluation of the Ferret prototype shows that (i) Ferret can refine object locations to only 1% of the reader’s coverage region in less than 2 min with small error rate (2.22%); (ii) Ferret can detect nomadic objects with 100% accuracy when the moving distances exceed 20 cm; and (iii) Ferret is robust against different movement patterns of user’s mobility. 相似文献
106.
Eugene Shi Guang Choo Erwin Peng Reshmi Rajendran Prashant Chandrasekharan Chang‐Tong Yang Jun Ding Kai‐Hsiang Chuang Junmin Xue 《Advanced functional materials》2013,23(4):496-505
This study proposes a new method to generate positive contrast in magnetic resonance imaging (MRI) using superparamagnetic contrast agents. Superparamagnetic nanostructures consisting of octahedron manganese ferrite nanoparticles embedded in spherical nanogels are fabricated using a bottom‐up approach. The composite nanoparticles are strongly magnetized in an external magnetic field and produce a unique NMR frequency shift in water protons, which can be demonstrated in MR spectroscopy and imaging to be different from the bulk pool. Moreover, the particles exhibit excellent colloidal stability in aqueous media and good cell biocompatibility. Hence, these particles are potentially useful as biomarkers by taking advantage of the positive contrast effects produced in MRI. 相似文献
107.
108.
Sharma Rachit Kumar Singh Prashant Kumar Sarkar Prabir Singh Harpreet 《Clean Technologies and Environmental Policy》2020,22(9):1871-1889
Clean Technologies and Environmental Policy - Companies are under increasing pressure to inculcate sustainability in their supply chain networks. However, the companies face significant amount of... 相似文献
109.
Hadi Shahnazari Prashant Mhaskar John M. House Timothy I. Salsbury 《American Institute of Chemical Engineers》2019,65(2):640-651
The problem of distributed fault detection and isolation (FDI) for heating, ventilation, and air conditioning (HVAC) systems has been addressed in this work. First, a linear model is identified for subunits of an HVAC system. Next, a local FDI (LFDI) framework is designed for each unit under consideration. A distributed FDI architecture is designed where the LFDI frameworks communicate to exchange information to achieve enhanced FDI in each unit. As a result, each LFDI framework functions as intended even in the presence of faults that affect multiple units. Effectiveness of the proposed distributed FDI framework is shown for various commonly occurring fault scenarios. © 2018 American Institute of Chemical Engineers AIChE J, 65: 640–651, 2019 相似文献
110.
In this article, an experimental comparison between open sun and solar drying is done. The thermal performance of evacuated tube based solar dryer is investigated with drying characteristics of Phyllanthus Emblica (Anvla), Aloe Vera, Aegle Marmelos (Bel) and leaves of Azadirachta Indica (Neem), Aegle Marmelos (Bel) and Psidium Guajava (Guava). In this setup, an evacuated tube collector, shell and tube heat exchanger and drying chamber are used. It was found that the maximum temperature difference between hot air and ambient air is 35.4°C and maximum efficiency of the setup is calculated as 55%. The average drying rate of Phyllanthus Emblica (Anvla), Aloe Vera and Aegle Marmelos (Bel) is measured as 0.46?g/min, 0.44?g/min, and 0.39?g/min respectively which are higher than that of Open Sun Drying. The leaves of Azadirachta Indica (Neem), Aegle Marmelos (Bel) and Psidium Guajava (Guava) also get dried with faster rates of 0.18?g/min, 0.17?g/min, and 0.14?g/min respectively. 相似文献