67 research outputs found
The multi-vehicle profitable pick up and delivery routing problem with uncertain travel times
Abstract This paper addresses a variant of the known selective pickup and delivery problem with time windows. In this problem, a fleet composed of several vehicles with a given capacity should satisfy a set of customers requests consisting in transporting goods from a supplier (pickup location) to a customer (delivery location). The selective aspect consists in choosing the customers to be served on the basis of the profit collected for the service. Motivated by urban settings, wherein road congestion is an important issue, in this paper, we address the profitable pickup and delivery problem with time windows with uncertain travel times. The problem under this assumption, becomes much more involved. The goal is to find the solution that maximizes the net profit, expressed as the difference between the collected revenue, the route cost and the cost associated to the violation the time windows. This study introduces the problem and develops a solution approach to solve it. Very preliminary tests are performed in order to show the efficiency of developed method to cope with the problem at hand
The Impacts of Distance between Phosphor Layers on Optical Properties of Triple-Layer Phosphor Structure
One of the crucial goals often thought of in connection with remote phosphors is to make the emitted photon larger than other structures. However, the two biggest hurdles that make achieving the goals more challenging are color uniformity and Color Rendering Index (CRI). This is the reason why people have started to pay more attention to these issues in recent research papers. Thus, this study will present the idea of controlling the distance between phosphor layers to control the optical parameters of White light LED (WLED). Based on the Mie scattering theory, which is about absorption and scattering of plane electromagnetic waves by uniform isotropic particles of the simplest form (sphere, infinite cylinder) which are in a uniform and isotropic dielectric infinite medium, the results of the study are confirmed to be completely accurate and reliable. Specifically, when d = 0.64 mm, the flux can increase to 9.7% compared to the original. Similarly, when d = 0.84 mm, the color uniformity can be double better meanwhile the CRI value is kept intact. Once fully calculated and substantiated, the paper will provide comparable results in practice for the production of higher quality WLED
Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio
Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications
Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio
Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two\ua0non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications
Antibacterial, antioxidant and cytotoxic activities of different fractions of acetone extract from flowers of Dipterocarpus intricatus Dyer (Dipterocarpaceae)
This study has shown for the first time the antimicrobial, antioxidant and cytotoxicity of 3 fractions of acetone extract, including hexane, chloroform and ethyl acetate from flowers of Dipterocarpus intricatus. Antibacterial test using disc diffusion method showed that the chloroform and ethyl acetate fractions inhibited the growth of all the tested bacteria, including Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus and Staphylococcus aureus while the hexane fraction showed the antibacterial activity against B. cereus and S. enteritidis. Antioxidant activity and cancer cell resistance of those extracts were conducted using DPPH and MTT methods respectively. As a result, the DPPH radical scavenging activity of the hexane, chloroform and ethyl acetate fractions were determined with the IC50 values of 0.508, 0.22 and 0.075 mg/mL respectively while the cytotoxicity to HepG2 cell line of those fractions was 163.3 ppm, 106.7 ppm and 459.3 ppm. These results suggested the potential application of these fractions isolated from D. intricatus flowers as the natural antimicrobial, antioxidant and cytotoxic agents for medicine
Multifunctional nanocarriers of Fe3O4@PLA-PEG/curcumin for MRI, magnetic hyperthermia and drug delivery
Background: Despite medicinal advances, cancer is still a big problem requiring better diagnostic and treatment tools. Magnetic nanoparticle (MNP)-based nanosystems for multiple-purpose applications were developed for these unmet needs. Methods: This study fabricated novel trifunctional MNPs of Fe3O4@PLA-PEG for drug release, MRI and magnetic fluid hyperthermia. Result: The MNPs provided a significant loading of curcumin (∼11%) with controllable release ability, a high specific absorption rate of 82.2 W/g and significantly increased transverse relaxivity (r2 = 364.75 mM-1 s-1). The in vivo study confirmed that the MNPs enhanced MRI contrast in tumor observation and low-field magnetic fluid hyperthermia could effectively reduce the tumor size in mice bearing sarcoma 180. Conclusion: The nanocarrier has potential for drug release, cancer treatment monitoring and therapy.The authors are grateful for the financial support by AOARD under award FA2386-17-1-4042. The Spanish government is acknowledged for the “Nanotechnology in translational hyperthermia (HIPERNANO)” research network (RED2018102626-T) and for funding under the project number MAT2017-83631-C3. NTK Thanh thanks EPSRC (EP/M015157/1). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed
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