Showing papers by "Saurabh Srivastava published in 2019"

Site characterization through combined analysis of seismic and electrical resistivity data at a site of Dhanbad, Jharkhand, India

Abstract: We present the seismic site characterization study using joint modelling of Horizontal-to-Vertical Spectral-Ratio (HVSR) and Rayleigh wave-phase velocity-dispersion curves obtained from Multi-channel Simulation with One Receiver (MSOR) in a part of Dhanbad, Jharkhand, India. The joint analysis of these two different but complementary datasets puts stronger constraints on the model parameter search space than one dataset and may help us in finding more unique shear-wave velocity model. The microtremor data from 12 observation points were utilized to iteratively search 1D shear-wave velocity profiles in a predefined model search space. These 1D shear-wave velocity models were interpolated to generate a 2D shear-wave velocity profile of the site using the cubic spline method. Our results show that the high peak amplitude value of HVSR is associated with low peak-period values of HVSR at a distance of ~ 60 m from the southern end of the profile; which may indicate the presence of the Basin Edge Effect. We identified four layers based on significant changes in the shear wave velocities to a depth of ~ 60 m. The major impedance contrasts are located at average depths of ~ 13 m, ~ 40 m and ~ 55 m, respectively. These layers from the surface may indicate the presence of soil, highly weathered rock mass, moderately weathered rock and bedrock, respectively. The depth of engineering solid bedrock (Vs > 600 m/s) is found at the depth of 55 m in the south which gradually decreases to a depth of 40 m in the northern end of the profile. The shear-wave velocity (Vs 30) for this area varies between 293 and 357 m/s; which can be classified as “D-type site”. For validation and comparison of our results, the Electrical Resistivity Tomography (ERT) data were also recorded along the same traverse using Wenner and Schlumberger configurations. Our results show a significant amount of correlation between the 2D shear-wave velocity and resistivity profiles obtained from joint analysis of tremor and ERT data.

A Review of UAV Regulations and Policies in India

Abstract: The emergence of Unmanned Aerial Vehicle (UAV) is driving a paradigm shift in research and development. Initially, UAVs were limited for defense purposes only. Now, these are getting popular and are widely used in different sectors such as infrastructure, mining, and media. With the increase in usage of UAVs, legal and policy complexities of drone laws have also increased. However, the current legal framework that regulates UAVs, needs to be reviewed due to the rapid increase in UAV’s market in India. The introduction of national drone policy from Director General of Civil Aviation (DGCA) which is UAVs regulatory body in India, reduces the ambiguities in the system. However, some bottlenecks still exist. The present policy legalizes the use and operation of drones in India which needs to be analyzed carefully. This paper examines the existing UAVs regulations and issues like safety, security, and privacy associated with the use of drones. The complexities in the existing law and major policy gaps in India are also analyzed. Moreover, a comparative analysis of existing national and international drone laws is presented with emphasis on the registration of aircraft and important guidelines in regard to the qualification and license for pilots.

Hospitality of chatbot building platforms

Abstract: The temptation to be able to talk to a machine is not new. Recent advancements in the field of Natural Language Understanding has made it possible to build conversational components that can be plugged inside an application, similar to other components. These components, called chatbots, can be created from scratch or with the help of commercially available platforms. These platforms make it easier to build and deploy chatbots, often without writing a single line of code. However, similar to any other software component, chatbots also have quality concerns. Despite significant contributions in the field, an architectural perspective of building chatbots with desired quality requirements is missing in the literature. In the current work, we highlight the impact of features provided by these platforms (along with their quality) on the application design process and overall quality attributes. We propose a methodological framework to evaluate support provided by a chatbot platform towards achieving quality in the application. The framework, called Hospitality Framework, is based on software architectural body of knowledge, especially architectural tactics. The framework produces a metric, called Hospitality Index, which has utilities for making various design decisions for the overall application. We present the use of our framework on a simple use case to highlight the phases of evaluation. We showcase the process by picking three popular chatbot platforms - Watson Assistant, DialogFlow and Lex, over four quality attributes - Modifiability, Security & Privacy, Interoperability and Reliability. Our results show that different platforms provide different support for these four quality attributes.

A Reference Architecture for Applications with Conversational Components

Abstract: Providing a multi-modal user interface adds value to any application. Allowing users to speak or chat with the system is one such area where software practitioners are putting a lot of effort. This involves building components which can understand the nuances of human conversation. Such components, often called “chatbots, can be built either from scratch, or using a commercial platform. The process of architecting such applications may differ significantly from the “conventional” applications that the software practitioners usually build. In this work, we present a Reference Architecture for building such applications. We apply the Reference Architecture to a sample use-case and provide two Concrete Architectures for the same. The two architectures are designed keeping in mind, two commercial platforms, IBM Watson Assistant and Google DialogFlow, assuming that they were used to build the conversational components.

PUTWorkbench: Analysing Privacy in AI-intensive Systems

Abstract: AI intensive systems that operate upon user data face the challenge of balancing data utility with privacy concerns. We propose the idea and present the prototype of an open-source tool called Privacy Utility Trade-off (PUT) Workbench which seeks to aid software practitioners to take such crucial decisions. We pick a simple privacy model that doesn't require any background knowledge in Data Science and show how even that can achieve significant results over standard and real-life datasets. The tool and the source code is made freely available for extensions and usage.