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Nowadays traditional techniques of living and earning are being transformed to modern smart technologies, taking their inspiration from the emerging trends. Agriculture and its supply chain are also one of the major domains of research that need attention for its growth especially in developing countries like Pakistan. Food safety and its supply are drawing the world's attention towards its importance and people are focusing on it because of health hazards. This research, presents a Combo smart model with a novel scheme for the transformation of traditional agriculture to smart agriculture, taking into consideration both blockchain and Internet of Things ( IoT) characteristics. The system proves to be reliable, automatic, open, and biological food tracks built with the features of Blockchain IoT devices. This system provides equal opportunity to all stakeholders involved in the agricultural food supply chain; even they are not familiar with each other and may not trust. IoT devices are added to the smart model to reduce human interference for data recording and verification. For validation purposes, the proposed scheme is compared to our own scheme, which uses only IoT devices deployed in the monitoring field without a blockchain.

The use of automated network planning systems is crucial for reducing the deployment cost and planning time of passive optical telecommunication networks. Mixed-integer linear programming (MILP) is well suited for the purpose of modeling passive optical networks; however, excessive computing times for solving large-scale problem instances render these approaches impractical. This research presented a formulation that was based on MILP. It is for the issue of optimum dimensions of fiber equipment of the FTTH optical-access network (FTTH-OANs). The key objective is to minimize the capital expenditure associated with the implementation of FTTH-OAN, i.e. the expense of passive and active tools (splices, fiber terminations, closures, cables, optical splitters, and OLT cards, etc.) site planning costs and the cost of labor needed. This formulation is installed and tested. The key results are derived from practical physical systems installed in homes.

Multi-tone-based wavelength division multiplexed passive optical networks are considered to provide cost-effective access network solution. We analysed and revealed the transmission performance, power budget concern and the cost investigation of the multi-tone-based WDM PON. A differential phase shift keying and re-modulated return to zero on/off keying signals for downlink and uplink, respectively, are transmitted via a single-mode fibre. The transmission performance of the proposed architecture is analysed using key parameters of bit error rate and optical signal to noise ratio using different data rates and channel spacing. The simulation results are in agreement with the theoretical analysis. The power budget is calculated for both upstream and downstream data signals showing excellent system margins for any unseen losses. The proposed setup is also analysed in terms of cost to prove it the cost-effective solution for the next-generation optical access networks.

User Equipment (UE) is equipped with limited cache resources that can be utilized to offload data traffic through device-to-device (D2D) communications. Data caching at a UE level has the potential to significantly alleviate data traffic burden from the backhaul link. Moreover, in wireless networks, users exhibit mobility that poses serious challenges to successful data transmission via D2D communications due to intermittent connectivity among users. Users’ mobility can be exploited to efficiently cache contents by observing connectivity patterns among users. Therefore, it is crucial to develop an efficient data caching mechanism for UE while taking into account users’ mobility patterns. In this work, we propose a mobility-aware data caching approach to enhance data offloading via D2D communication. First, we model users’ connectivity patterns. Then, contents are cached in UE’ cache resources based on users’ data preferences. In addition, we also take into account signal-to-interference and noise ratio (SINR) requirements of the users. Hence, our proposed caching mechanism exploits connectivity patterns of users to perform data placement based on users’ own demands and neighboring users to enhance data offloading via cache resources. We performed extensive simulations to investigate the performance of our proposed mobility-aware data caching mechanism. The performance of our proposed caching mechanism is compared to most deployed data caching mechanisms, while taking into account the dynamic nature of the wireless channel and the interference experienced by the users. From the obtained results, it is evident that our proposed approach achieves 14%, 16%, and 11% higher data offloading gain than the least frequently used, the Zipf-based probabilistic, and the random caching schemes in case of an increasing number of users, cache capacity, and number of contents, respectively. Moreover, we also analyzed cache hit rates, and our proposed scheme achieves 8% and 5% higher cache hit rate than the least frequently used, the Zipf-based probabilistic, and the random caching schemes in case of an increasing number of contents and cache capacity, respectively. Hence, our proposed caching mechanism brings significant improvement in data sharing via D2D communications.

The impact of major nonlinearities in optical fiber such as SRR (Stimulated Raman Scattering) and Four Wave Maxing (FWM) in cascaded amplifier Dense Wavelength Division Multiplexing optical long reach and high speed data rate transmission scheme have been investigated at different data rates. Pulse walk off effect is considered for the purpose of calculating Stimulated Raman Scattering (SRS) nonlinear factor. Examination has been accomplished to assess signal to noise ratio thinking about the consolidated impact of SRS and FWM within the sight of amplified spontaneous emission noise to achieve minutest noise at altered data rates.

The demand for high-speed internet with a high-capacity network is increasing at an exponential rate. It is quite challenging to accommodate a large number of users with multiple communication devices without degrading the quality of service at an acceptable cost. Therefore, strong communication technology is required that can provide high data rates along with the provision of multiple connecting devices for different users. The 5G network can adjust large users with multiple device connectivity by providing high bandwidth with a minimum delay which depends on the underlying network architecture for connecting different components of the systems. Optical Fiber is used as a transmission media to connect the densely deployed Remote Radio Units (RRUs) with the Baseband Units (BBUs) at the Centralized Radio Access Network (C-RAN) that makes the architecture quite complex and expensive in terms of deployment and maintenance cost. Here in this paper, we propose an architecture by replacing an optical fiber with Free Space Optics (FSO) at the front-end of the 5G network. In addition, an Orthogonal Frequency Division Multiple Access (OFDMA) is implemented to provide high spectrum efficiency and high data rate in an adverse channel environment. The performance analysis of the proposed system is done in Optisystem by using the constellation points which shows that the proposed architecture can support data rate up to 40 Gbps using 512 subcarriers and 10 Gbps per BBU with QPSK over 4 km of FSO medium. In the end, a comparative cost analysis of the proposed architecture with the conventional architecture is done, which shows a cost reduction of 21 % by the proposed system.

Mobile Ad hoc network is the collection of nodes without having any physical structure involved i.e. access points, routers etc. MANETs are wide-open to similar forms of threats as other wireless mobile communication systems. In Ad-hoc Network nodes performing both as end-points of the communication and routers which makes the Ad-hoc routing protocols further prone towards the security attacks. Black Hole attack is a common security issue encountered in MANET routing protocols. The Black-Hole attack is security attack in which a malicious node imposters themselves as a node with the shortest hop count to the destination node during a packet transmission. A malicious node is capable of disturbing the network with Black Hole attack pretends to have the minimum hop-count route to the destination node (DS). This node responds to all route requests (RREQ) messages in positive and thus catches all the transmission to it. The source node (SN) not knowing the malicious nature of the Black-Hole node thus transmits all the important data. The Black Hole node discards all the important data packets. In this paper a comparatively effective, efficient and easy implemented way for identifying and therefore eluding the attacks of Black-Hole in mobile Ad-hoc networks is presented. The Network Simulator (NS-2) has been used for the implementation of our proposed solution to assess its work in terms of Network Routing load, End-to-End delay and Packet delivery ratio. The results show a considerable improvement in the performance metrics.

Patch antennas are modern elements of today’s world communication technology. They appear to have unique characteristics and features with their unique power with handling capabilities and lighted structure. This paper focuses on superstrate configuration of patch antenna with defected ground plane and Pi Slotted radiating patch. The three different cases were taken in terms of wavelength distance to observe the performance characteristics of patch structure. The antenna designed in this study can be used for S and C band applications.

With the intention to meet the increasing demand of future higher bandwidth applications, fiber based Gigabit Passive Optical Network (GPON) access is considered best resolution to deliver triple play services (voice, data, video). Hence, it becomes obligatory to migrate from traditional copper-based network to fiber-based. Due to rapid technological evolution, tough competition and budget limitation the service providers are struggling to provide a cost effective solution to minimize their operational cost with extra ordinary customer satisfaction. One of the factors that increase the cost of overall Fiber To The Home (FTTH) network is the unplanned deployment resulting in utilization of extra components and resources. Hence, it is imperative to determine a suitable technique, which helps to reduce planning process, required time and deployment cost through optimization. Automation based planning is one of the possible ways to automate the network design at probable lowest cost. In this research, a planning technique for migration from copper to fiber access network with a manageable and optimized Passive Optic Network (PON –FTTx) infrastructure is presented identifying a cost-effective strategy for developing countries.

This article has been retracted at the request of the Editor-in-Chiefdue to extended similarites with an unpublished paper, written by other authors, that was submitted (but not yet published) to several other journals and was probably leaked during the review process. The authors of the unpublished paper contacted the Editor-In-Chief with the above claim after the publication of this issue and ETASR has contacted several of the journals mentioned and the investigation resulted in the confirmation of the report. The authors of this paper failed to provide any reasoning regarding the case.

Antennas particularly patch have played a dominant role in in modern communication technologies. This study focuses on miniaturization and enhancement of bandwidth and other performance parameters like gain, directivity and return loss of quad band Pi-shaped patch antenna using superstrate configuration. A single miniaturaized element is designed and then its results are enhanced by implementing superstrate configuration on variable distance levels 12mm apart each. Computer Simulation Technology 2014 s is used for design and analysis of proposed structure. The proposed antenna showed satisfactory results and can be used for C and Ku band applications.

A novel technique for miniaturization of microstrip patch antenna is proposed for Portable and multifunctional Communication systems. Our proposed design consists of fractal patch, E-Shaped slot on fractal patch with first iteration and combination of H-Shape and L-Shape slots on the Ground plane. In this way we get smaller size antenna which is smaller than the conventional antenna. The most interesting feature of our proposed design is that we are getting multiband response in the frequency range of 1–8GHZ having Directivity in the range of 3.58dBi–6.39dBi, Gain in the range of 2.43dB–5.32dB and good impedance bandwidth for desired bands. As we have used the fractal patch with substrate FR4. Co-axial cable is used as a feeding method. We also employed shorting pin between fractal patch and ground plane. By the combination of all these proposed technique size of antenna is reduced 60.60% and it produces multiband response while the impedance bandwidth and gain are satisfactory for each band. We can adjust different bands by changing position of shorting pin. This type of smaller size antenna has applications in mobile phone as well as for S-Band and C-Band applications.

Due to their smaller size and light weighted structures patch antennas are accustomed in modern communication Technology. With additional size in reduction, micro strip antennas are commonly used in handsets, GPS receivers etc. This paper presents a novel design of fractal shape patch antenna using U-slot on patch and defected ground structure. Due to slots on patch and ground, tri-band resonating response is attained with maximum gain and directivity of 4.22dB and 6.51dBi showing high impedance bandwidth and radiation efficiency. The antenna showed good VSWR of 1.63 to 1.02 thus, showing high efficiency. As evident in the simulation results, the proposed antenna has been found useful for W-LAN, GSM, Radio Satellite, Fixed Satellite Services (RSS) & (FSS) and satellite communication systems.

We proposed and demonstrated the generation and transmission of 10-Gbps return-to-zero ON/OFF keying (RZ-OOK) signal using a new technique without pulse carving at transmitter. The new technique is characterized by a 3 dB built-in gain with better tolerance for chromatic dispersion in standard single mode fiber (SSMF). Fiber Bragg grating (FBG) is used as chromatic dispersion compensating device to investigate the tolerance of the proposed scheme. The simulation model of wavelength division multiplexing (WDM) based on OptiSystem.v.8.0 is presented. Simulation results show that there are error free transmission performance in a distance of 600 km with negligible power penalty and improved receiver sensitivity compared to conventional pulse carving approach.

The high speed internet infrastructure, quest for IT resource optimization and escalating operation and maintenance cost of keeping digital resources up are leading to a cost effective and technologically efficient business solution with computing resources available on demand and consumption pattern on pay per use basis. The flexibility of scaling up or down the IT resource pool for dynamic services and reduced CAPEX & OPEX for IT industry makes it a viable solution. This is the phenomenon in which computing resources are treated as a utility. The concept is not totally new but the evolution of ICT with reliable broadband infrastructure has made it pragmatic now. This paper discusses the concept of Cloud Computing, proposed cloud models and services options, economic opportunities and challenges.

Super resolution is a process to improve the resolution of an imaging system. Super resolution techniques can help in detection and recognition of objects of interest. A review of super resolution techniques applied to the radar technology is presented. The well-known super resolution algorithms, Matrix inverse, Minimum mean square error and Singular value decomposition are investigated. We observed that Minimum mean square error better recognize the targets under different conditions. Simulation results provide the assessment of discussed super resolution algorithms for the imaging model.

In recent years cloud computing has gained a momentum and is transforming the internet computing infrastructure. Also the mobile applications and mobile devices are developing rapidly. Cloud computing is anticipated to bring an innovation in mobile computing, where the mobile devices can use clouds for data processing, storage and other intensive operations. Already there are some mobile cloud applications for example Google's Map, Gmail for iPhone and Cisco's WebEx on iPad, however these applications are using the Software as a Service model. In this paper we introduce state-of-the-art Mobile Cloud Computing and its implementation methods. We also investigate some critical issues to be solved and point-out further future research directions.

There is a driving need for digital images of high resolution and quality in different Multimedia applications. However, a high resolution digital camera is still very expensive in the market. To meet such demand of today, the super resolution techniques promises to provide a high resolution image for multiple low resolution input images. But to judge the performance of existing super resolution algorithms objectively is a difficult task because lack of sufficient realiable testing tools. In this paper, it is shown that the existing Full Reference (FR) metrics cast shadows on the overall quality of super resolved image so judging super resolution quality using them is not an good idea. The main reasons for that is they do not take the visual masking phenomenon into consideration and also, they depends on the reference input, which itself may be of low quality. Experimental results shows that there is a need for a new Full Reference metric that shed light on the quality of reconstructed image in order to compare the performance of different existing super resolution (SR) methods.

Introduction: There are reports and controversy in the literature of supranormal (defined as >55%) differential renal function (DRF) in the hydronephrotic kidney in children with unilateral hydronephrosis. It is not confirmed whether supranormal DRF is an artifact or a true finding. In patients in whom the relative renal function deteriorates, relief of obstruction becomes surgically necessary and if this artifact can be removed. Supranormal function in an obstructed kidney is confusing and there is no consensus on how to manage these patients. There is no agreement if this is a true entity or an artifact. We wanted to address this issue by reporting our experience. Methods: We reviewed all the consecutive cases from August 2000 to October 2001 who were studied in our center with the diagnosis of unilateral renal obstruction for confirmation or evaluation of DRF. All patients had MAG-3 studies that were interpreted by experienced nuclear medicine physicians. The DRF were measured within the first to second minute of the MAG-3 injection. Regions of interest were drawn by the imaging software and the images were corrected for background counts by drawing regions of interest 2 pixels away from the edge of the renal cortex. Results: Fifty-seven patients were confirmed to be obstructed unilaterally; 41 (72%) patients had obstructive lesions in the left kidney and 16 (28%) in the right kidney. There was no case of supranormal DRF in the obstructed kidneys in our study. Conclusion: The supranormal renal function, as noted in some reports in the literature, was not seen in any patients at our institution. We believe that this entity is an artifact and can be avoided by using MAG-3 and projecting regions of interest by computer software; we plan to start analyzing multiple algorithms in phantoms with different ROI selection for background analysis.