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Fragmented spectrum allocations at RF and mm-Wave, increased use of carrier aggregation/MIMO and dense spectrum-reuse in wireless links has led to interest in the design of integrated wideband, high-linearity MIMO RX that provide low noise, blocker tolerance and reconfigurability across signal domains. In this paper, receive architectures for wide operating range and blocker tolerance are presented with a focus on recent developments in reconfigurable N-path receivers. Generalized sequence-mixing architectures that support reconfigurable frequency/spatial/code-domain rejection and filtering are described along with directions of research extending operation to wider bandwidths and higher frequencies.

The growing production and usage of autonomous, cooperative mobile robots are going to be an integral part of our daily lives in the upcoming years. In this paper, a two agent master slave system has been explored wherein the slave imitates the master. Master slave robot communication form an important segment of swarm robotics and intelligence. Slaves generally follow the commands of the master. We particularly explore a domain wherein the slave imitates the motion of the master. We approach to demonstrate the master slave communication and eventual demonstration of imitation while keeping the whole arrangement and system’s cost low. We use low cost alternatives of other communication methodologies while essentially maintaining the reliability.

With the ever-expanding social net, the use cases of irony detection and classification is also exponentially increasing. With this work, we take Task3 of SemEva1-2018 as our problem statement which further has two tasks. We intend to first determine if a given tweet is ironic or not (Task A) and then classify the tweets into four classes viz. non-ironic, verbal irony with contrast, verbal irony without contrast and situational irony (Task B). Existing papers have mainly exploited the lexical features of tweets using supervised machine learning. Here, we have proposed two NLP Transformer models viz. BERT (Bidirectional Encoder Representations from Transformers) and XLNets to classify tweets and have also compared our results to that of past papers. Using BERT, we have achieved F1 scores of 0.70 and 0.75 and using XLNets 0.74 and 0.59 for Task A and Task B respectively.

The electrical power distribution network (PDN) is in the transition phase due to the integration of distributed energy resources (DERs). Therefore, an accurate and efficient modeling and simulation platform is the need of the hour to determine the dynamic behavior of the PDN. The recent computational hardware, such as GPU, FPGA, etc. enables new simulation paradigm and develop a more realistic platform in the form of system emulators. In this paper, an FPGA based electromagnetic transient (EMT) simulation framework for the PDN is presented. Conjugate-gradient (CG) based electrical network solver is implemented in the proposed framework, and a test case is analyzed for Jail substation of Guwahati city, India, to validate the simulation environment. It has been compared with the MATLAB based implementation for verifying its accuracy. The proposed EMT simulator is approximately 12.5 times faster as compared to its MATLAB implementation and exhibits good accuracy as well.

This paper extends N-path filtering to the code domain by proposing code-modulated local oscillator signals. A correlator-based perspective of N-path mixer receiver (RX) is presented to demonstrate interferer-rejection and desired signal reception in a code-domain N-path RX. Pairs of Walsh-function-based codes are proposed for modulating desired RX and known interferers [such as self-interference (SI) from transmitter (TX)] to achieve high interferer rejection. An N-path architecture for concurrent reception of two code-modulated signals is also presented. A 0.3–1.4-GHz 65-nm CMOS implementation achieves 35-dB gain for desired signals and concurrently receives two RX signals while rejecting mismatched spreading codes at RF input. The proposed TX SI mitigation approach results in 38.5-dB rejection for −11.8 dBm 1.46-Mb/s quadrature phase-shift keying (QPSK) modulated SI at the RX input. The RX achieves 23.7-dBm output referred 1dB gain compression (OP1dB) for in-band SI, while consuming ~35 mW and occupies 0.31 mm2. Such code-domain selection/rejection can be used in conjunction with other N-path filtering schemes for signal selection/rejection based on a combination of spatial, spectral, and code-domain properties.

Even with the use of most sophisticated microscope sometimes the relationship between the aneurysm and the adjacent structures are not clearly defined. The straight line of view by microscope results in inadequate visualization of structures that lie immediately behind other structures like the neck, branches or perforators of the aneurysm. Hence exposure of these structures may require risky retraction either of the parent artery or the aneurysm itself, which can be overcome by clear anatomical information obtained by the use of endoscope instead of attempting extensive manipulation under the microscope. The endoscope permits close up, wide angled views of regional anatomic features and verification of the optimal clip position. Visual conformation of regional anatomy achieved using the rigid endoscope provides valuable information for subsequent microsurgical procedures and enhances the safety and reliability. Endoscopic-assisted microsurgery is an exceptional aid and using the PIP (picture-in picture) technology, simultaneous observation of microscope and endoscopic images can be viewed through the ocular system of microscope. The advantages of neuroendoscope include the ability to look around corners and behind obstructions. With less brain retraction, smaller operative exposures and better visualization, neuroendoscopy may reduce operative morbidity. However the surgeon should be familiar with this technique and be prepared for the inconveniences and risks during the procedure.

Impedance translation using passive N-path mixers has been used to achieve local oscillator (LO)-defined series bandstop and shunt bandpass filtering. In this paper, we generalize N-path filtering using a correlator-based approach and propose N-path passive mixers driven by orthogonal sequences. Such sequence-driven N-path filters can potentially reject or select signals based on their properties in the spectral, spatial, and code domains. Specifically, a Walsh-function (WF) sequence (WF-seq)-based N-path shunt filter is implemented, demonstrating the feasibility of shunt bandstop filtering using LO sequences other than nonoverlapping pulses. The WF-seq approach enables reconfigurable concurrent filtering at two different frequencies with shunt operation avoiding penalties due to the switch drive overlap. A 65-nm CMOS implementation achieves 20-dB rejection at one frequency and 14-dB rejection concurrently at two frequencies between 0.3 and 1.4 GHz. The reconfigurable bandstop filter is implemented using analog gyrators and consumes 35–62.5 mW and achieves 2.9-dB noise figure and −2.5–5-dBm IIP3.

In this paper, transfer learning using pre-trained Convolutional Neural Network models such as GoogleNet and AlexNet is employed for X-Ray image classification and retrieval. This is carried out on IRMA database comprising of 55 categories of 6406 X-Ray images. These images are preprocessed using adaptive histogram equalization. The performance of the networks have been evaluated over five trials considering an 80:20 training to validation set split resulting in an average accuracy of 0.87 and 0.93 for GoogleNet and AlexNet, respectively. Confusion matrices are generated which is used to estimate the precision and recall of the networks. The proposed work resulted in a robust X-Ray image classification mechanism.

Applying orthogonal sequences to N-path filters promises reconfigurable select/reject filtering of signals based on their spatial, spectral and code-domain properties. Achieving code and frequency-domain notch filtering using inductors instead of capacitors has been challenging due to parasitics and self-resonance associated with large off-chip inductors. In this work, N-path frequency/code-domain reject and select filtering is demonstrated using N-path switching with passive inductors. A cascaded inductor approach and differential N-path filtering is used to overcome inductor parasitics and enable GHz operation. A 65-nm CMOS prototype of a code-domain notch filter followed by a code-domain select receiver demonstrates 0.5 GHz to 1.0 GHz operation with 26 dB blocker filtering with 8 dBm power handling, while consuming 60 mW (at 1 GHz LO) and occupying 1.2 mm2 of die area.

Fifth-generation cellular communication standards (5G) target Gb/s data-rates, pushing the industry beyond the sub-6GHz bands. Tens of GHz of spectrum are available in the frequency bands from 30 to 300GHz. To maintain acceptable link budgets with sufficient antenna apertures, arrays are typically required at these frequencies and electrical beam steering is needed to retain spatial coverage. For such complex systems, highly-integrated, low-cost and energy-efficient SoCs are desirable to enable volume deployment. FinFET technologies are an ideal candidate to tackle this challenging integration, given the excellent balance between density and RF/mm-wave performance that has been recently demonstrated [1].

Solar energy has emerged as a viable source of renewable energy over the past few decades and is now used for various applications such as emergency lighting, water heaters, and industrial application. It is a cheap source of energy. Sun is the renewable energy source available to everyone. Unlike hydro or Thermal electricity it does not cause any pollution This paper proposes the design of a cost effective and solar based automatic irrigation system. The objective is to design a low cost microcontroller based irrigation system. The sensor senses the moisture of soil and provides signal to the motor to turn ON or turn OFF the irrigating pump for optimal utilization of water by the farmers.

The digital age has given rise to a new form of bullying, termed cyberbullying. A majority of teens use some sort of social media service, thus leading to cyber bullying becoming quite rampant and in some extreme cases, also resulting in victim suicides. In this paper, we aim to show the results of the system we designed for the automatic monitoring and prevention of cyberbullying. The response grading system takes into account the severity of bullying and gives appropriate responses.

Digital beamforming/MIMO arrays provide increased capacity, flexibility and reconfigurability but the absence of spatial filtering of jammers prior to the ADC restricts RX linearity. In this work, a reconfigurable, scalable parallel spatio-spectral notch filtering (PSNF) array is presented that incorporates orthogonal Walsh function sequence mixing with N-path passive mixers. Sequence mixing and impedance translation of passive mixers result in concurrent notching at each element's RF input for two independent frequencies/angles-of-incidence defined by the sequence driving the mixers. A 0.3 GHz-1.4 GHz four-element array prototype implemented in 65-nm CMOS achieves > 15-dB notch filtering at RF input for two blockers while causing < 3-dB NF degradation. The array achieves ∼28-dBm RX OIP3 (with PSNF enabled) and wireless measurements demonstrate spatial rejection of in-band blockers.

Mobile Ad hoc Network (MANET) is a position of mobile phone devices like which correspond surrounded by each other in excess of wireless relations lacking a preconceived communications or a essential weight. The associate nodes are self dependent pro design, function also continuation of the association by means of only hop or multi hop communication. In existing work, RSA and Triple DES algorithm are used to detect malicious nodes but we performed greedy approaches and encryption which provides much better results. This shows in the NS2 Simulation which proved that our methodology is far better than the existing work.

Validation of analog IP's at high frequency is performed on a test board. For proper validation of IP's, it is very necessary to characterize the transmission line in such a manner that how much amount of signal is received at the destination & how much amount of losses introduce the transmission line. This paper proposed, Fixture free characterization of transmission line mounted on test board, based on advanced SOLT calibration performed on test dummy structure (ISS).Extraction of RLGC parameters, attenuation constant and phase constant of transmission line in very simple manner. Advanced probes technology minimizes insertion and return losses at high frequency which introduce by the adopters. Fixture free characterization minimizes phase delays produced by the adopters. Keywords: thetransmission line, SOLT Calibration, Test dummy structure (ISS), ACP GS probes

The emergence of battery-constrained system-on-chip (SoC) devices, such as smartphones and tablets, requires hardware/software codesign to optimize battery life. Offloading activities from the processor to specialized engines on the SoC can help reduce power consumption.

Software behavior can significantly affect computer energy efficiency in everything from small devices up to servers in data centers. However, there are multiple techniques that software developers can use to reduce the energy consumption of drivers and applications.

Our research primarily focuses on developing mechanisms to intelligently route autonomous vehicles in an urban area while managing to reduce traffic congestion. We propose an Intelligent Transportation System for Autonomous vehicles based on Multi-Agent paradigm. These agents observe traffic conditions over a period of time. Historical traffic information along with information of factors that affects traffic(like weather conditions) are used to develop a regression based learning algorithm that predicts time required to traverse a route for a given time-slot, which can be used to find out shortest path for a given source-destination pair, before beginning to travel. This estimated traverse time for every lane is communicated to the vehicles. Based on this information, the vehicles find out k shortest paths. Reservation based protocols are used to obtain a single path such that the overall congestion is minimized and the destination is reached in the shortest possible time. The shortest path obtained is then traversed with the help the vehicle control system with optimized fuel efficiency, ensuring vehicle stability and obstacle avoidance. To achieve this path trajectory, we used nonlinear Model Predictive control (MPC) approach based on bicycle model of vehicle dynamics. The main advantage of MPC is the fact that it allows the current time-slot to be optimized, while taking future time-slots into account. We further investigate the linear MPC strategies for Co-operative adaptive Cruise control which directly minimizes the fuel consumption.

Community detection is one of the most widely studied tasks in network analysis because community structures are ubiquitous across real-world networks. These real-world networks are often both attributed and dynamic in nature. In this paper, we propose a community detection algorithm for dynamic attributed graphs that, unlike existing community detection methods, incorporates both temporal and attribute information along with the structural properties of the graph. Our proposed algorithm handles graphs with heterogeneous attribute types, as well as changes to both the structure and the attribute information, which is essential for its applicability to real-world networks. We evaluated our proposed algorithm on a variety of synthetically generated benchmark dynamic attributed graphs, as well as on large-scale real-world networks. The results obtained show that our proposed algorithm is able to identify graph partitions of high modularity and high attribute similarity more efficiently than state-of-the-art methods for community detection.

The advent of the digital age has paved the way for a new form of bullying which often leads to social stigma. With an increase in the use of social media platforms by adolescents, cyber bullying has become quite rampant and in some extreme cases it has also resulted in suicides by the victims. Very little efforts have been taken to curb this social menace and hence, this paper tries to address this issue by reviewing the steps that can be undertaken to detect cyber bullying on online social networks. This paper aims to review the different methods and algorithms used for detection in cyber bullying and provide a comparative study amongst them so as to decide which method is the most effective approach and provides the best accuracy.

This paper describes WOW, a distributed system that combines virtual machine, overlay networking and peer-to-peer techniques to create scalable wide-area networks of virtual workstations for high-throughput computing. The system is architected to: facilitate the addition of nodes to a pool of resources through the use of system virtual machines (VMs) and self-organizing virtual network links; to maintain IP connectivity even if VMs migrate across network domains; and to present to end-users and applications an environment that is functionally identical to a local-area network or cluster of workstations. We describe a novel, extensible user-level decentralized technique to discover, establish and maintain overlay links to tunnel IP packets over different transports (including UDP and TCP) and across firewalls. We also report on several experiments conducted on a testbed WOW deployment with 118 P2P router nodes over PlanetLab and 33 VMware-based VM nodes distributed across six firewalled domains. Experiments show that the latency in joining a WOW network is of the order of seconds: in a set of 300 trials, 90% of the nodes self-configured P2P routes within 10 seconds, and more than 99% established direct connections to other nodes within 200 seconds. Experiments also show that the testbed delivers good performance for two unmodified, representative benchmarks drawn from the life-sciences domain. The testbed WOW achieves an overall throughput of 53 jobs/minute for PBS-scheduled executions of the MEME application (with average single-job sequential running time of 24.1s) and a parallel speedup of 13.5 for the PVM-based fastDNAml application. Experiments also demonstrate that the system is capable of seamlessly maintaining connectivity at the virtual IP layer for typical client/server applications (NFS, SSH, PBS) when VMs migrate across a WAN

Computer vision researchers have recently developed automated methods for rating the aesthetic appeal of a photograph. Machine learning techniques, applied to large databases of photos, mimic with reasonably good accuracy the mean ratings of online viewers. However, owing to the many factors underlying aesthetics, it is likely that such techniques for rating photos do not generalize well beyond the data on which they are trained. This paper reviews recent attempts to compare human ratings, obtained in a controlled setting, to ratings provided by machine learning techniques. We review methods to obtain meaningful ratings both from selected groups of judges and also from crowd sourcing. We find that state-of-the-art techniques for automatic aesthetic evaluation are only weakly correlated with human ratings. This shows the importance of obtaining data used for training automated systems under carefully controlled conditions. MOE (Min. of Education, S’pore) Published version

Biped robots are more versatile than conventional wheeled robots, but they tend to tip over easily. The dynamic stability of a biped robot needs to be maintained during walking. In this paper, a novel approach to compute dynamically stable walking motions of a planar six degree-of-freedom biped is presented. This approach is analytical and is based on the need for periodicity of the motion. The resulting gait satisfies the dynamic stability criteria. Sets of joint motions for different step sizes and speed of walking, i.e., quasi-statically and dynamically stable walking patterns, can be obtained.

New and efficient paradigms for web-based collaborative product design in a global economy will be driven by increased outsourcing, increased competition, and pressures to reduce product development time. We have developed a three-tier (client-serverdatabase) architecture based collaborative shape design system, Computer Aided Distributed Design and Collaboration (CADDAC). CADDAC has a centralized geometry kernel and constraint solver. The server-side provides support for solid modeling, constraint solving operations, data management, and synchronization of clients. The client-side performs real-time creation, modification, and deletion of geometry over the network. In order to keep the clients thin, many computationally intensive operations are performed at the server. Only the graphics rendering pipeline operations are performed at the client-side. A key contribution of this work is a flexible architecture that decouples Application Data (Model), Controllers, Viewers, and Collaboration. This decoupling allows new feature development to be modular and easy to develop and manage. @DOI: 10.1115/1.1582882#

The battery life of mobile devices is one of their most important resources. Much of the literature focuses on accurately profiling the power consumption of device components or enabling application developers to develop energy-efficient applications through fine-grained power profiling. However, there is a lack of tools to enable users to extend battery life on demand. What can users do if they need their device to last for a specific duration in order to perform a specific task? To this extent, we developed BatteryExtender, a user-guided power management tool that enables the reconfiguration of the device's resources based on the workload requirement, similar to the principle of creating virtual machines in the cloud. It predicts the battery life savings based on the new configuration, in addition to predicting the impact of running applications on the battery life. Through our experimental analysis, BatteryExtender decreased the energy consumption between 10.03% and 20.21%, and in rare cases by up to 72.83%. The accuracy rate ranged between 92.37% and 99.72%.

Any system that is able to reliably measure the aesthetic appeal of photographs would be of considerable importance to the digital imaging industry. Researchers have built automated rating systems using machine learning techniques applied to features extracted from images. In this paper, we study the effectiveness of ACQUINE, a comprehensive and publicly available rating system, using data obtained from voters in a crowd sourced manner. We analyze the effect of voting using a simple binary like/dislike rating in comparison to a numerical 10 point scale. We also show that global measures of image quality, such as contrast or colorfulness, do not correlate well with human ratings. The role of composition in determining human rating of aesthetics is discussed.

Resolving excessive power dissipation of modern computer systems has become a substantial challenge. However, few research projects have targeted on application power analysis or application-aware power management, which becomes a rising factor in energy efficient system design. In this paper, we describe and implement an application function (subroutine call) level profiler, Safari. It can be used to generate power profiles of each function in an automatic manner. The experiment results using NPB parallel benchmark suite show that Safari is able to collect function level run-time information with overhead (16% on average) comparable to gprof. The power profiling results can be used for code optimization, power-aware scheduling, or even computing resource billing for future research.

Technology clients expect with the release of a new device model that the device is more powerful and more energy efficient than its predecessor. There are many profiling tools aimed at profiling the energy efficiency of different platforms in order to provide consumers fair comparison of the energy efficiency of available platforms. Since improving the power consumption of devices is no longer the sole duty of hardware manufacturers but it is also the responsibility of software developers, we present a case study in this paper where we power profile Windows® 8 and Windows® 7 on the same hardware configuration using MobileMark® 2012 in order to compare how their efficiency compare to one another. Based on our results, we were able to show that Windows® 8 is a step forward to a better energy efficient operating system when compared to its predecessor.

In the present Web services scenario, user demands are complex in nature and cannot be answered by a single Web Service. Composite services need to be constructed to fulfill such demand. QoS is an important aspect of service composition. The overall QoS of the composite service may be decided by the QoS offered by the constituting component services. Therefore a complex service should be formed using component services with matching QoS values. In this paper, a method has been proposed to form complex service sets using component services with matching QoS values such that user’s cost requirement is also satisfied. Availability, response time and throughput are important QoS parameters. Very few number of sets are presented to the user in the form of a list such that the set with best QoS appears at the top. The proposed method thus is very useful for the user and enables him to avail the complex service with best QoS.

Extending the battery life by reducing the power impact of software applications is becoming increasingly important in mobile computing systems. Several power estimation tools are being developed for software applications, but a gap exists in using them to instrument software applications for better power footprint. In this paper, we analyze idle and active power management scenarios of software applications and target minimizing OS-application interaction as our goal for obtaining power savings. A timer tick varying strategy is shown to reduce power consumption by 3 Watts for multimedia playback software.

With recent advances in virtual computing and the revelation that compute-intensive tasks run well on system virtual machines (VMs), the ability to develop, deploy, and manage distributed systems has been ameliorated. This paper explores the design space of VM-based sandboxes where the following techniques that facilitate the deployment of secure nodes in wide-area overlays of virtual workstations (WOWs) are employed: DHCP-based virtual IP address allocation, self-configuring virtual networks supporting peer-to-peer NAT traversal, stacked file systems, and IPsec-based host authentication and end-to-end encryption of communication channels. Experiments with implementations of single-image VM sandboxes, which incorporate the above features and are easily deployable on hosted I/O VMMs, show execution time overheads of 10.6% or less for a batch- oriented CPU-intensive benchmark.

This poster describes current work on the application of network virtualization and peer-to-peer routing techniques that overlay IP traffic and provide seamless connectivity to virtual machines in grid computing. Such IP-over-P2P virtual network - IPOP - is an overlay network that uses a virtual IP address space and allows nodes that belong to a grid to be seamlessly pooled together. The overlay network is self-configured as nodes join/leave the virtualized grid, and IP-level bi-directional connectivity among peers is provided. The decoupling provided by the overlay enables grid applications to leverage a wealth of IP-based software typically available in local-area environments. Such virtual networks, when combined to complementary resource virtualization techniques provided by O/S virtual machines [Xen, Rarham et al. (2003), VMware, Sugerman et al., (2001), User Mode Linux, Dike, J. (2000)], provide a scalable framework for dealing with a fundamental goal of grid computing: sharing resources in a secure and flexible manner by Figueiredo, Dinda and Fortes (2003)

Gravity balancing is often used in industrial machines to decrease the actuator efforts during motion. Through the use of rehabilitation devices one can also partially balance the leg during motion with the goal to reduce net joint torque during motion. However, it is not clear as to what are the effects of such devices on legged locomotion. This paper aims to study the effect of such gravity balancing devices on the motion of bipeds during walking.

To enhance the ENVISION interface and facilitate user interaction, various techniques were considered for better rendering of search results with improved scalability. In this paper we discuss the challenges we encountered and our solutions to those problems.