Jog C.,IIIT Bangalore |
Agrawal S.,IIIT Bangalore |
Srinivasa S.,IIIT Bangalore
ACM International Conference Proceeding Series | Year: 2015
Inter-organizational collaborations involve exchange of sensitive, utilitarian data. Such data exchanges require efficiently designed trust frameworks to explain data accesses in terms of the business logic of the collaboration, without becoming an obstacle itself. In addition, there may be restrictions on the participating organizations in terms of legal jurisdiction, physical location, and corporate policies. Other important issues like privacy, provenance and confidentiality also pose challenges. In this work, we propose a distributed trust framework that allows organizations to share data while adhering to the restrictions, thus enabling collaborations. The framework limits data publishing and access within semantic boundaries called"worlds"and provides scalable access-control mechanisms based on user credentials over the worlds. In this paper, we address the problem of distributing such a framework across several organizations, without compromising on the logic of data specification and trusted access control. Copyright 2015 ACM.
Prabhu H R.,IIIT Bangalore |
Rao S.,IIIT Bangalore
International Conference on Intelligent Systems Design and Applications, ISDA | Year: 2012
Data streams are vast sources of information. In such streams only certain episodic points called events are interesting. The number of events occurring in a data stream can be very large, and a given user would not be interested in all of them. Thus, there is a need to selectively disseminate information about the occurrence of events to users who express interest in them. Publish/Subscribe is a distributed paradigm of messaging in which events published by publishers are automatically sent to subscribers who have expressed interest in them. In this work, we apply the publish/subscribe paradigm to notify a user when an event of interest occurs. Furthermore, user subscriptions may often be vague and non-specific. To capture this uncertainty, we use fuzzy set theory in the modeling of the subscriptions. The use of fuzzy sets gives a user more expressive power in subscriptions and gives better notifications of events. © 2012 IEEE.
JayPrakash L.T.,IIIT Bangalore
2013 IEEE 1st International Workshop on Communicating Business Process and Software Models: Quality, Understandability, and Maintainability, CPSM 2013 | Year: 2013
We propose a technique for analysis of impact of design changes using dynamic slicing of UML models. For a software architecture specified using UML, we first transform a given model into a graph representation which we have named Model Dependency Graph (MDG). MDG combines information available in the interaction model along with the relevant information available in class model into an integrated model. For a given slicing criterion, our slicing algorithm traverses the constructed MDG to identify the relevant model elements forming the dynamic slice. We use these slices to identify the model changes, and their impact. Our impact analysis methodology is based on using the difference between the dynamic slices computed before and after changes are made to the model. Our methodology's novelty lies in performing impact analysis based on a graph metamodel as against independently processing separate UML models. © 2013 IEEE.
Arora R.,IIIT Bangalore |
Srinivasa S.,IIIT Bangalore
2014 6th International Conference on Communication Systems and Networks, COMSNETS 2014 | Year: 2014
Increasing amounts of user generated content (UGC) on the Internet, is creating research interest in opinion mining. This involves automatic detection of opinions about products, services, political parties, celebrities and events from user generated content. Research efforts in opinion mining are thus far, fragmented and have followed several approaches. However, most of them require understanding of domain-specific opinion words and their polarity, and language-specific opinion rules. In addition, semantic constructs like sarcasm pose open challenges. In this paper, we try to characterize the opinion-mining landscape by proposing a faceted taxonomy of the different aspects of opinion mining. We then survey literature and place these in appropriate places in the proposed model. We also propose a general purpose workflow required from any opinion mining engine. Finally, we speculate on specific challenges in the opinion mining landscape. © 2014 IEEE.
Saxena A.,Indian Institute of Technology Kharagpur |
Rao S.,IIIT Bangalore
International Journal of Reliability, Quality and Safety Engineering | Year: 2014
Degradation analysis is used to analyze the useful lifetimes of systems, their failure rates, and various other system parameters like mean time to failure (MTTF), mean time between failures (MTBF), and the system failure rate (SFR). In many systems, certain possible parallel paths of execution that have greater chances of success are preferred over others. Thus we introduce here the concept of probabilistic parallel choice. We use binary and n-ary probabilistic choice operators in describing the selections of parallel paths. These binary and n-ary probabilistic choice operators are considered so as to represent the complete system (described as a series-parallel system) in terms of the probabilities of selection of parallel paths and their relevant parameters. Our approach allows us to derive new and generalized formulae for system parameters like MTTF, MTBF, and SFR. We use a generalized exponential distribution, allowing distinct installation times for individual components, and use this model to derive expressions for such system parameters. © 2014 World Scientific Publishing Company.
Haloi M.,Indian Institute of Technology Guwahati |
Jayagopi D.B.,IIIT Bangalore
IEEE Intelligent Vehicles Symposium, Proceedings | Year: 2015
In this work, we have developed a robust lane detection and departure warning technique. Our system is based on single camera sensor. For lane detection a modified Inverse Perspective Mapping using only a few extrinsic camera parameters and illuminant Invariant techniques is used. Lane markings are represented using a combination of 2nd and 4th order steerable filters, robust to shadowing. Effect of shadowing and extra sun light are removed using Lab color space, and illuminant invariant representation. Lanes are assumed to be cubic curves and fitted using robust RANSAC. This method can reliably detect lanes of the road and its boundary. This method has been experimented in Indian road conditions under different challenging situations and the result obtained were very good. For lane departure angle an optical flow based method were used. © 2015 IEEE.
Agrawal P.,IIIT Bangalore |
Rao S.,IIIT Bangalore
e-Energy 2015 - Proceedings of the 2015 ACM 6th International Conference on Future Energy Systems | Year: 2015
It is known that energy-minimal scheduling is strictly harder than minimal-makespan scheduling, but it is not well understood. This paper is a study of the problems of scheduling to minimize the energy consumed by a system of dissimilar machines (with no restriction on the makespan). The different system types considered are for machines with identical speeds but different power ratings, and for machines with different speeds and power ratings but no idle power consumption. The results give insights for further studies classifying various types of energy-minimal scheduling problems, and for deriving algorithms for exact or approximate solutions for such problems. © 2015 ACM.
Das D.,IIIT Bangalore
Proceedings of the 2016 IEEE International Conference on Wireless Communications, Signal Processing and Networking, WiSPNET 2016 | Year: 2016
Apart from research being done on using SDN in wired networks, there have been attempts made to extend similar concepts in wireless domain as well, to improve network performance. There have been several architectural proposals put forward which includes concepts like reconfigurable data plane in base-stations e.g. OpenRadio to different Radio Access Technology (RAT). These ideas can be extended further to improve mobility of the UEs. It is known fact that intra-RAT mobility (e.g. LTE to LTE) is far more efficient than inter-RAT (e.g. LTE to UMTS) counterparts in terms of latency and complexity. Hence, it would be useful in a futuristic network if inter-RAT mobility procedures can be converted to intra-RAT ones by configuring some of base-stations dynamically to required RAT based on pattern of UE mobility. In this paper, we show how deployment of reconfigurable base-stations improve the overall mobility of UEs in a multi-RAT cellular network by increasing number of intra-RAT mobility procedures and in turn decreasing the time consuming inter-RAT mobility procedures. Simulation results reveal, as deployment of reconfigurable base-stations increases there is a maximum increase of 11% in probability of intra-RAT mobility procedures undergone by UEs in the network. Also, this increase in intra-RAT mobility saturates beyond a certain percentage of deployment of reconfigurable base-stations. © 2016 IEEE.
Ganesan R.,Infosys |
Sarkar S.,Infosys |
Narayan A.,IIIT Bangalore
Proceedings - 2012 IEEE 5th International Conference on Cloud Computing, CLOUD 2012 | Year: 2012
Sharing of physical infrastructure using virtualization presents an opportunity to improve the overall resource utilization. It is extremely important for a Software as a Service (SaaS) provider to understand the characteristics of the business application workload in order to size and place the virtual machine (VM) containing the application. A typical business application has a multi-tier architecture and the application workload is often predictable. Using the knowledge of the application architecture and statistical analysis of the workload, one can obtain an appropriate capacity and a good placement strategy for the corresponding VM. In this paper we propose a tool iCirrus-WoP that determines VM capacity and VM collocation possibilities for a given set of application workloads. We perform an empirical analysis of the approach on a set of business application workloads obtained from geographically distributed data centers. The iCirrus-WoP tool determines the fixed reserved capacity and a shared capacity of a VM which it can share with another collocated VM. Based on the workload variation, the tool determines if the VM should be statically allocated or needs a dynamic placement. To determine the collocation possibility, iCirrus-WoP performs a peak utilization analysis of the workloads. The empirical analysis reveals the possibility of collocating applications running in different time-zones. The VM capacity that the tool recommends, show a possibility of improving the overall utilization of the infrastructure by more than 70% if they are appropriately collocated. © 2012 IEEE.
Rao M.,IIIT Bangalore
Advanced Materials Research | Year: 2014
A novel way of three dimensional (3D) chip stacking has been designed in a view to improve heat dissipation across the layers. Chip stacking using vertical interconnections forms microscale channels for coolant to circulate through the gaps. Solder-based self assembled (SBSA) 3D structures have been designed as posts on simulated through silicon vias (TSVs) to prove the processing concept. The processing of SBSA structures using a low temperature solder alloy and dip soldering method is described. Additional processing steps to fabricate interconnected 3D structures were demonstrated. Mechanical grinding of the 3D structures shows that soldered SBSA structures were void free and robust enough to be used as a connection post for chip stacking. SBSA structures provide a solder bump that serves as a connection path in the integration of dissimilar electronic technologies. Conventional copper posts, developed in a previous project, can be an effective approach to integrated circuit (IC) stacking. However, the SBSA post provides more variety in size and shape with a potential to serve as a reservoir for solder to aid in chip bonding. The solder bumps are heat resistant and uniform thicknesses were obtained across a large array of SBSA structures. The electrical durability of SBSA posts were determined by completing I-V measurements after thermal treatments. Fabricated SBSA posts were subjected to thermal cycling with temperatures ranging from room temperature to 300 °C. The interconnected SBSA posts are shown to be stable until 165 °C with little variation in measured resistance. © (2014) Trans Tech Publications, Switzerland.