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51.
Highly-filled polymer systems include color masterbatches, feedstocks for powder injection molding, and rigid sheets with high levels of flame retardants, but they have not been explored for flexible sheet. This work investigated the (a) selecting a polymer matrix with enough melt strength and flexibility to form a stable sheet with high filler loading, (b) the maximum achievable filler loading for the sheet, and (c) optimizing the process of extruding a highly-filled flexible polymer system. Extrusion grade low-density polyethylene (LDPE) provided sufficient flexibility and permitted a maximum filler loading of 36 vol% (~78 wt%). Good dispersion of the nanoparticle filler, however, required two passes through multiple screw extruders and a small reduction in the viscosity of the LDPE. Sheet with thickness of 415 μm, surface roughness of <1 μm, and sufficient flexibility was extruded continuously at a rate of 10 m/min., but it required a more traditional coat hanger manifold to prevent filler hang up in the sheet die. The filler particles were distributed uniformly through the core and skin of the sheet, giving the sheet good mechanical properties.  相似文献   
52.
In the generation of electricity and cogeneration, Kalina cycle is considered as one of the competitors to organic Rankine cycle. With the simplicity and identical components of the binary mixture, Kalina system makes it more prominent to get developed and implemented as well with its environmental friendly associate. This work proposes a new improved Kalina cycle system to convert the natural source from sun to useful work. The proposed system utilizes heat source suitable to medium temperature heat applications. The proposed cycle have 2 units of solar collector, favoring an additional heat recovery and higher performance. Solar hot source temperature and pressure are 190°C and 45 bar with additional flow to the turbine of 1.15 kg/s. Energy and second law analysis have considered in evaluating the performance of the proposed plant. The energy analysis shows minimum value of net power, energy efficiency and plant efficiency as 241 kW, 15.5% and 5.7. The exergy analysis defines that, to the proposed cycle, the exergy efficiency initializes at 77% with more exergy destruction at turbine with 31%. With the parametric analysis, the system is amended to have the maximum values of energy and exergy performances as 18.5%, 7.1% and 85%. The parametric study identifies the optimum value of the inlet temperature and pressure of the pump and turbine.  相似文献   
53.
Wireless Personal Communications - Applications of wireless sensor networks (WSNs) are increasing tremendously to facilitate and establish a link between the physical world and information system....  相似文献   
54.
Wireless Personal Communications - Wireless sensor network consists of a number of power constrained sensor nodes that sense data from the environment. The collected data is directed to the base...  相似文献   
55.

Internet of Things (IoT) is changing the way many sectors operate and special attention is paid to promoting healthy living by employing IoT based technologies. In this paper, a novel approach is developed with IoT prototype of Wireless Sensor Network and Cloud based system to provide continuous monitoring of a patient’s health status, ensuring timely scheduled and unscheduled medicinal dosage based on real-time patient vitals measurement, life-saving emergency prediction and communication. The designed integrated prototype consists of a wearable expandable health monitoring system, Smart Medicine Dispensing System, Cloud-based Big Data analytical diagnostic and Artificial Intelligence (AI) based reporting tool. A working prototype was developed and tested on few persons to ensure that it is working according to expected standards. Based on the initial experiments, the system fulfilled intended objectives including continuous health monitoring, scheduled timely medication, unscheduled emergency medication, life-saving emergency reporting, life-saving emergency prediction and early stage diagnosis. In addition, based on the analysis reports, physicians can diagnose/decide, view medication side effects, medication errors and prescribe medication accordingly. The proposed system exhibited the ability to achieve objectives it was designed using IoT to alleviate the pressure on hospitals due to crowdedness in hospital care and to reduce the healthcare service delays.

  相似文献   
56.
Phytomediated synthesis of metal oxide nanoparticles has become a key research area in nanotechnology due to its wide applicability in various biomedical fields. The present work explores the biosynthesis of zinc oxide nanoparticles(ZnO-NPs) using Leucaena leucocephala leaf extract. The synthesised ZnO-NPs were characterised by ultraviolet-visible(UV-Vis) spectroscopy, scanning electron microscopy(SEM), energydispersive X-ray spectroscopy(EDX), Fourier transform infrared spectroscopy(FTIR), X-ray diffraction(XRD),transmission electron microscopy(TEM) and selected area electron diffraction(SAED) studies. Biosynthesised ZnONPs are found to have wurtzite hexagonal structure with particles distributed in the range of 50-200 nm as confirmed by TEM studies. The anticancer activity of ZnONPs against MCF-7(breast cancer) and PC-3(human prostate cancer) cell lines was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. From the assay, biosynthesised ZnO-NPs have better cytotoxic activity on PC-3 cell lines than MCF-7 cell lines. The in vitro cytotoxicity studies of biosynthesised ZnO-NPs against Dalton lymphoma ascites(DLA)cells reveal better antitumor activity of 92% inhibition with concentration of 200 μg·ml~(-1) of ZnO-NPs,and as the concentration increases, the anticancer efficiency as well increases, and also, it has excellent photocatalytic activity to degrade crystal violet dye in aqueous solution after irradiation of 90 min. The result suggests that the green synthesis of ZnO-NPs could be easily recovered and reused several times without any significant loss of the catalytic activity. The advantage of this technique lies in its low cost, easily climb able and non-use of toxic agents.  相似文献   
57.
Recently, Packet scheduling plays a vital role in Wireless Sensor Networks (WSNs). The major key challenges include delay, packet dropping, energy consumption and lifetime due to constraints in energy and computing resources. All the research works on packet scheduling scheme in WSN uses only First Come First Served (FCFS) and Dynamic Multilevel Priority (DMP) schemes. FCFS works based on packet arrival time, it leads to starvation and high processing overhead for real-time packets. DMP works in multilevel with dynamic priority reduces the transmission overhead and bandwidth; it consumes more resources for real-time task leads to deadlock. To solve these problems, this work presents Multilevel Dynamic Feedback Scheduling (MDFS) algorithm. The sensor node classifies the emergency and normal data into three different ready queues named as high, medium and low priority, respectively. The queues are connected with a feedback mechanism; each packet from the sensor node has its own time quantum value based on the deadline. The updated time quantum value is compared with the boundary value of the queues, depends on the updated value the data packets are moved between queues with help of feedback mechanism. The simulation result proves that the projected MDFS outperforms in WSN environment.  相似文献   
58.
Wireless Personal Communications - Matched filtering has found its way in many diverse applications such as communication, signal processing and more. The emphasis of this paper is on the design...  相似文献   
59.
60.
Wireless Personal Communications - Smart grid is an autonomous power generation and production system, that includes various energy management sub-systems such as energy efficient resources, smart...  相似文献   
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