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71.
72.
The cloud computing paradigm facilitates a finite pool of on-demand virtualized resources on a pay-per-use basis. For large-scale heterogeneous distributed
systems like a cloud, scheduling is an essential component of resource management at the application layer as well as at the virtualization layer in order to
deliver the optimal Quality of Services (QoS). The cloud scheduling, in general, is an NP-hard problem due to large solution space, thus, it is difficult to
find an optimal solution within a reasonable time. In application layer scheduling, the tasks are mapped to logical resources (i.e., virtual machines), aiming
to optimize one or more QoS parameters, and conforming to several constraints. Various algorithms have been proposed in the literature for application
layer scheduling, where each of them is based on some fundamental design techniques like simple heuristics, meta-heuristics, and most recently hybrid
heuristics. Although ample literature survey exists for cloud scheduling algorithms, none of them present their study exclusively for the application layer. In
this survey paper, we present a study on task scheduling algorithms used only at the application layer of the cloud. We classify our study according to various
fundamental techniques used in designing such scheduling algorithms. One of the main features of our study is that it covers numerous application type
e.g., a set of independent tasks, simple workflow, scientific workflow, and MapReduce jobs. We also provide a comparative analysis of existing algorithms
on various parameters like makespan, cost, resource utilization, etc. In the end, research directions for future work have been provided. 相似文献
73.
This paper improves the performance of 60‐GHz wireless optical system including radio over fibre (RoF) and radio over free space optics (RoFSO), based on novel reverse‐parallel (RP) hybrid modulation scheme. This scheme combines the chromatic dispersion compensation technique of parallel modulation with energy efficiency manipulation technique of reverse modulation. Superior functioning of RoFSO is provided with reverse modulation compared with normal modulation. Comparative investigations are performed by loading 60‐GHz RF signal with 2.5 and 10‐Gbps data and modulating it with both reverse and hybrid modulators. Hybrid modulation performed better with improved BER of 10?23 at distance of 51 km for 2.5‐Gbps data compared with reverse modulation with BER of 10?7. 相似文献
74.
Rathee Geetanjali Sandhu Rajinder Saini Hemraj Sivaram M. Dhasarathan Vigneswaran 《Wireless Networks》2020,26(4):2339-2351
Wireless Networks - In this paper, we have demoralized the transmission processing concerns of fog nodes and IoT device layer attack during the handoff (mobility) of IoT devices in the fog... 相似文献
75.
In this endeavor, a new multiple‐input‐multiple‐output antenna with a sharp rejection at wireless local area network (WLAN) band is designed and practically examined for portable wireless ultra‐wideband applications. The intended diversity antenna possess a small size of 15 mm × 26 mm and two inverted L‐strip are loaded over the conventional rectangular patch antenna to form protrudent‐shaped radiator that acts as a radiating element. The sharp band‐rejection capability at WLAN is established by incising the L‐shaped slits at the decoupling structure. More than ?21 dB isolation is accomplished for the complete working band (ie, 2.87 ‐17 GHz). Degradation in the antenna efficiency at the center frequency of band rejection corroborates the good interference rejection capability. The working capabilities of the intended antenna are tested by using the isolation between the ports, total efficiency, gain, envelope correlation coefficient, radiation pattern, mean effective gain, and total active reflection coefficient. 相似文献
76.
Chauhan Digvijay Singh Singh Amit Kumar Kumar Basant Saini J. P. 《Multimedia Tools and Applications》2019,78(4):3911-3923
Multimedia Tools and Applications - In this paper, an improved wavelet based medical image watermarking algorithm is proposed. Initially, the proposed technique decomposes the cover medical image... 相似文献
77.
Vandita Kakkar Indu Pal Kaur Amrit Pal Kaur Komal Saini Kamalinder K. Singh 《Drug development and industrial pharmacy》2018,44(10):1701-1712
Tetrahydrocurcumin (THC) also referred to as ‘white curcumin’, is a stable colorless hydrogenated product of curcumin with superior antioxidant and anti-inflammatory properties. The present study is an attempt to elevate the topical bioavailability of THC, post-incorporation into a nano-carrier system with its final dosage as a hydrogel. Lipid nanoparticles of THC (THC-SLNs) prepared by microemulsification technique were ellipsoidal in shape (revealed in transmission electron microscopy) with a mean particle size of 96.6?nm and zeta potential of ?22?mV. Total drug content and entrapment efficiency of THC-SLNs was 94.51%?±?2.15% and 69.56%?±?1.35%, respectively. Differential scanning calorimetry and X-ray diffraction studies confirmed the formation of THC-SLNs. In vitro drug release studies showed the drug release from THC-SLNs gel to follow Higuchi’s equation revealing a Fickian diffusion. Ex vivo permeation studies indicated a 17 times (approximately) higher skin permeation of THC-SLNs gel as compared with the free THC gel. Skin irritation, occlusion, and stability studies indicated the formulation to be nonirritating, and stable with a desired occlusivity. Pharmacodynamic evaluation in an excision wound mice model clearly revealed the enhanced anti-inflammatory activity of THC-SLNs gel and was further confirmed using biochemical and histopathological studies. It is noteworthy to report here that THC-SLNs gel showed significantly better (p?≤?0.001) activity than free THC in gel. As inflammation is innate to all the skin disorders, the developed product opens up new therapeutic avenues for several skin diseases. To the best of our knowledge, this is the first paper elaborating the therapeutic usefulness of white curcumin-loaded lipidic nanoparticles for skin inflammation. 相似文献
78.
Kumar Pradeep Saini Rajkumar Roy Partha Pratim Dogra Debi Prosad 《Multimedia Tools and Applications》2018,77(7):8823-8846
Multimedia Tools and Applications - Sign language is the only means of communication for speech and hearing impaired people. Using machine translation, Sign Language Recognition (SLR) systems... 相似文献
79.
The need for recycling of polymeric waste has been well recogmized as a result of the escalating prices of the petrochemical feedstocks and the growing awareness to curtail solid waste that causes environmental pollution. During processing, the molecular weight of the polymer is reduced due to thermal and shear degradation. Since the melt rheology of the processed material is sensitive to the changes in molecular structure, knowledge of the complete flow curve depicting the variation of melt viscosity with shear rate at processing temperatures is a useful tool for assessing the reprocessibility of waste material and for specifying the conditions of reprocessing. In the present paper, an effective method is proposed to generate the melt flow curves of polymer waste from knowledge of its melt flow index. The method makes use of a master curve that can be obtained by plotting the available viscosity data in terms of modified functions based on the melt flow index. The master curves characteristic of the particular generic resin type are presented for low-density polyethylene, polypropylene and polystyrene. 相似文献
80.
Wireless Personal Communications - Now-a-days the most common pretentious disease is the lung cancer, which has become more prevalent in the world that primarily infects the pulmonary nodules of... 相似文献