Data aggregation is a promising solution for minimizing the communication overhead by merging redundant data thereby prolonging the lifetime of energy starving Wireless Sensor Network (WSN). Deployment of heterogeneous sensors for measuring different kinds of physical parameter requires the aggregator to combine diverse data in a smooth and secure manner. Supporting multi functional data aggregation can reduce the transmission cost wherein the base station can compute multiple statistical operations in one query. In this paper, we propose a novel secure energy efficient scheme for aggregating data of diverse parameters by representing sensed data as number of occurrences of different range value using binary encoded form thereby enabling the base station to compute multiple statistical functions over the obtained aggregate of each single parameter in one query. This also facilitates aggregation at every hop with less communication overhead and allows the network size to grow dynamically which in turn meets the need of large scale WSN. To support the recovery of parameter wise elaborated view from the multi parameter aggregate a novelty is employed in additive aggregation. End to end confidentiality of the data is secured by adopting elliptic curve based homomorphic encryption scheme. In addition, signature is attached with the cipher text to preserve the data integrity and authenticity of the node both at the base station and the aggregator which filters out false data at the earliest there by saving bandwidth. The efficiency of the proposed scheme is analyzed in terms of computation and communication overhead with respect to various schemes for various network sizes. This scheme is also validated against various attacks and proved to be efficient for aggregating more number of parameters. To the best of our understanding, our proposed scheme is the first to meet all of the above stated quality measures with a good performance.
Scheduling procedures implemented in wireless networks consists of varied workflows such as resource allocation, channel gain improvement, and reduction in packet arrival delay. Among these techniques, Long term evolution (LTE) scheduling is most preferable due to its high speed communication and low bandwidth consumption. LTE allocates resources to the workflow based on time and frequency domains. Normally, the information gathered prior to scheduling increases the processing time since each attributes of the users have to be verified. In order to solve this issue, parallel processing via data mining is analyzed in recent research studies. The label that is assigned to the user attributes contributes primarily on scheduling time slots effectively. The label assignment and parallel processing via data mining reduces the delay and increases the throughput respectively. Additionally, the matched data extraction from the library and the prediction of available channels with fewer dimensions posed major challenges in the LTE scheduling. This paper surveys about various LTE scheduling algorithms, dimensionality reduction techniques, optimal feature selection techniques, multi-level classification techniques, and data mining combined with LTE techniques. A brief survey illustrates the impact of each technique on 3G/4G networks, channel availability prediction, scheduling of time slots in detail. A brief comparison of the techniques involved in the respective LTE processes via tabular form reveals that the verification of channel and user availability are the primary functions of the LTE scheduling. The survey of this paper identifies the limitations such as computational complexity and poor scheduling performance in the existing systems and encourages researchers to develop novel algorithms for LTE scheduling. 相似文献
Forming limit diagram (FLD) is an important performance index to describe the maximum limit of principal strains that can be sustained by sheet metals till to the onset of localized necking. It is useful tool to access the forming severity of a drawing or stamping processes. In the present work, FLD has been determined experimentally for Ti-6Al-4 V alloy at 400 °C by conducting a hemispherical dome test with specimens of different widths. Additionally, theoretical FLDs have been determined using Marciniak Kuczynski (M-K) model. Various yield criteria namely: Von Mises, Hill 1948, Hill 1993 and Cazacu Barlat in combination with different hardening models viz., Hollomon power law (HPL), Johnson-Cook (JC), modified Johnson-Cook (m-JC), modified Arrhenius (m-Arr.), modified Zerilli–Armstrong (m-ZA) have been used in M-K analysis for theoretical FLD prediction. The material properties required for determination of yield criteria and hardening models constants have been calculated using uniaxial tensile tests. The predicted theoretical FLDs results are compared with experimental FLD. It can be observed that influence of yield criterion in M-K analysis for theoretical FLD prediction is predominant than the hardening model. Based on the results; it is observed that the theoretical FLD using Cazacu Barlat and Hill 1993 yield criteria with m-Arr. hardening model has a very good agreement with experimental FLD. 相似文献
A new lumped conceptual model based on the Soil Conservation Service Curve Number (SCS-CN) concept has been proposed in this
paper for long-term hydrologic simulation and it has been tested using the data of five catchments from different climatic
and geographic settings of India. When compared with the Mishra et al. (2005) model based on variable source area (VSA) concept, the proposed model performed better in all applications. Both the models
however exhibited a better match between the simulated and observed runoff in high runoff producing watersheds than did in
low runoff producing catchments. Using the results of the proposed model, dominant/dormant processes involved in watershed’s
runoff generating mechanism have also been identified. The presented model is found useful in the continuous simulation of
rainfall–runoff process in watersheds. 相似文献
This paper presents the idea of automated learning in virtual communities through “tarka”-based argumentative discussions. Prior to argumentative discussion, both the discussing agents will have various degrees of belief about the subject of discussion, in their respective knowledge bases. To attain valid knowledge about a particular subject, both the participants voluntarily undergo a tarka process where arguments and counter-arguments are interchanged, pertaining to several knowledge-sharing criteria. At the end of discussion, gathered valid beliefs about the subject of discussion are generated as definitions from the knowledge base, to demonstrate the value of knowledge shared (and learned) via argumentation. 相似文献
The effects of multi-walled CNTs and array of channels are combined to form Double-walled Gate Wrap Around Carbon Nano Tube array Field Effect Transistor (DWGWA CNTFET). Numerical model is proposed for the device to study its performance. Screening and imaging effects of adjacent and inter walls in array of channels are included for calculating the drive capacitance, subsequently the drive current. This model suits for a wide range of chiralities and diameters. The change in drive capacitance of double-walled and single-walled device with respect to various drain and gate voltage for different values of number of channels, diameters are studied. The number of channels, CNTs diameters, chiralities of the tubes, source/drain length are varied and the corresponding responses of drive current, cut off frequency, signal delay time for both double and single walled devices are compared. In all cases, DWGWA CNTFET excels in its performance over Single-walled Gate Wrap Around Carbon Nano Tube array Field Effect Transistor (SWGWA CNTFET).The model of the proposed device can be utilized for designing the Nano devices with high power and high speed capability. 相似文献
Mobile Networks and Applications - The tour of sensor is astounding. Researchers are recognizing the problems of storing sensors on cloud and preserved in a remarkable way. Applications of Wireless... 相似文献
Multimedia Tools and Applications - This paper proposes a digital image reversible data hiding method in integer lifting transform domain. Owing to the characteristics of the natural image... 相似文献