scholarly journals Multi-Stage Conversational Passage Retrieval: An Approach to Fusing Term Importance Estimation and Neural Query Rewriting

2021 ◽  
Vol 39 (4) ◽  
pp. 1-29
Author(s):  
Sheng-Chieh Lin ◽  
Jheng-Hong Yang ◽  
Rodrigo Nogueira ◽  
Ming-Feng Tsai ◽  
Chuan-Ju Wang ◽  
...  
Keyword(s):  
Information Seeking ◽  
Ad Hoc ◽  
State Of The Art ◽  
Vital Role ◽  
Query Rewriting ◽  
Query Reformulation ◽  
Passage Retrieval ◽  
Multi Stage ◽  
Natural Language Dialogue ◽  
Reciprocal Rank

Conversational search plays a vital role in conversational information seeking. As queries in information seeking dialogues are ambiguous for traditional ad hoc information retrieval (IR) systems due to the coreference and omission resolution problems inherent in natural language dialogue, resolving these ambiguities is crucial. In this article, we tackle conversational passage retrieval, an important component of conversational search, by addressing query ambiguities with query reformulation integrated into a multi-stage ad hoc IR system. Specifically, we propose two conversational query reformulation (CQR) methods: (1) term importance estimation and (2) neural query rewriting. For the former, we expand conversational queries using important terms extracted from the conversational context with frequency-based signals. For the latter, we reformulate conversational queries into natural, stand-alone, human-understandable queries with a pretrained sequence-to-sequence model. Detailed analyses of the two CQR methods are provided quantitatively and qualitatively, explaining their advantages, disadvantages, and distinct behaviors. Moreover, to leverage the strengths of both CQR methods, we propose combining their output with reciprocal rank fusion, yielding state-of-the-art retrieval effectiveness, 30% improvement in terms of NDCG@3 compared to the best submission of Text REtrieval Conference (TREC) Conversational Assistant Track (CAsT) 2019.

scholarly journals Security Challenges of Location Privacy in VANETs and State-of-the-Art Solutions: A Survey

2021 ◽  
Vol 13 (4) ◽  
pp. 96
Author(s):  
Shawal Khan ◽  
Ishita Sharma ◽  
Mazzamal Aslam ◽  
Muhammad Zahid Khan ◽  
Shahzad Khan
Keyword(s):  
Traffic Control ◽  
Critical Analysis ◽  
Location Privacy ◽  
Ad Hoc ◽  
State Of The Art ◽  
Vital Role ◽  
Safe Driving ◽  
Information Event ◽  
Location Privacy Protection ◽  
Smart Traffic

A Vehicular Ad-hoc Network (VANET) comprises a group of moving or stationary vehicles connected by a wireless network. VANETs play a vital role in providing safety and comfort to drivers in vehicular environments. They provide smart traffic control and real-time information, event allocation. VANETs have received attention in support of safe driving, intelligent navigation, emergency and entertainment applications in vehicles. Nevertheless, these increasingly linked vehicles pose a range of new safety and security risks to both the host and its associated properties and may even have fatal consequences. Violations of national privacy and vehicle identities are a major obstacle to introducing forced contact protocols in vehicles. Location privacy refers to the privacy of the vehicle (driver) and the location of the vehicle. Whenever a vehicle sends a message, no one but authorized entities should know their real identity and location of the vehicle. All the messages sent by the vehicle must be authenticated before processing, hence location privacy is an important design aspect to be considered in VANETs operations. The novelty of this paper is that it specifically reviews location privacy in VANETs in terms of operational and safety concerns. Furthermore, it presents a critical analysis of various attacks, identity thefts, manipulation and other techniques in vogue for location privacy protection available in state-of-the-art solutions for VANETs. The efforts in this paper will help researchers to develop a great breadth of understanding pertaining to location privacy issues and various security threats encountered by VANETs and present the critical analysis of the available state-of-the- art solutions to maintain location privacy in VANETs.

scholarly journals State-of-the-art methods and devices for generation, exposure, and collection of aerosols from e-vapor products

2020 ◽  
Vol 4 ◽  
pp. 239784732097975
Author(s):  
Stéphanie Boué ◽  
Didier Goedertier ◽  
Julia Hoeng ◽  
Anita Iskandar ◽  
Arkadiusz K Kuczaj ◽  
...  
Keyword(s):  
Ad Hoc ◽  
State Of The Art ◽  
Physicochemical Characterization ◽  
Objective Evaluation ◽  
Vapor Generation ◽  
Characterization Methods ◽  
Clinical Exposure ◽  
Aerosol Generation

E-vapor products (EVP) have become popular alternatives for cigarette smokers who would otherwise continue to smoke. EVP research is challenging and complex, mostly because of the numerous and rapidly evolving technologies and designs as well as the multiplicity of e-liquid flavors and solvents available on the market. There is an urgent need to standardize all stages of EVP assessment, from the production of a reference product to e-vapor generation methods and from physicochemical characterization methods to nonclinical and clinical exposure studies. The objective of this review is to provide a detailed description of selected experimental setups and methods for EVP aerosol generation and collection and exposure systems for their in vitro and in vivo assessment. The focus is on the specificities of the product that constitute challenges and require development of ad hoc assessment frameworks, equipment, and methods. In so doing, this review aims to support further studies, objective evaluation, comparison, and verification of existing evidence, and, ultimately, formulation of standardized methods for testing EVPs.

scholarly journals CorGAT: a tool for the functional annotation of SARS-CoV-2 genomes

2020 ◽  
Author(s):  
Matteo Chiara ◽  
Federico Zambelli ◽  
Marco Antonio Tangaro ◽  
Pietro Mandreoli ◽  
David S Horner ◽  
...  
Keyword(s):  
Functional Annotation ◽  
Ad Hoc ◽  
State Of The Art ◽  
Supplementary Information ◽  
Genomic Sequences ◽  
Supplementary Data ◽  
Evolutionary Patterns ◽  
Genomic Variants ◽  
Art Methods ◽  
Available Resources

Abstract Summary While over 200 000 genomic sequences are currently available through dedicated repositories, ad hoc methods for the functional annotation of SARS-CoV-2 genomes do not harness all currently available resources for the annotation of functionally relevant genomic sites. Here, we present CorGAT, a novel tool for the functional annotation of SARS-CoV-2 genomic variants. By comparisons with other state of the art methods we demonstrate that, by providing a more comprehensive and rich annotation, our method can facilitate the identification of evolutionary patterns in the genome of SARS-CoV-2. Availabilityand implementation Galaxy   http://corgat.cloud.ba.infn.it/galaxy; software: https://github.com/matteo14c/CorGAT/tree/Revision_V1; docker: https://hub.docker.com/r/laniakeacloud/galaxy_corgat. Supplementary information Supplementary data are available at Bioinformatics online.

scholarly journals On the relation between mini-halos and AGN feedback in clusters of galaxies

2020 ◽  
Vol 499 (2) ◽  
pp. 2934-2958
Author(s):  
A Richard-Laferrière ◽  
J Hlavacek-Larrondo ◽  
R S Nemmen ◽  
C L Rhea ◽  
G B Taylor ◽  
...  
Keyword(s):  
Large Scale ◽  
State Of The Art ◽  
Vital Role ◽  
Clusters Of Galaxies ◽  
Relativistic Jets ◽  
X Ray ◽  
Core Cluster ◽  
Central Galaxy ◽  
Central Regions ◽  
Radio Power

ABSTRACT A variety of large-scale diffuse radio structures have been identified in many clusters with the advent of new state-of-the-art facilities in radio astronomy. Among these diffuse radio structures, radio mini-halos are found in the central regions of cool core clusters. Their origin is still unknown and they are challenging to discover; less than 30 have been published to date. Based on new VLA observations, we confirmed the mini-halo in the massive strong cool core cluster PKS 0745−191 (z = 0.1028) and discovered one in the massive cool core cluster MACS J1447.4+0827 (z = 0.3755). Furthermore, using a detailed analysis of all known mini-halos, we explore the relation between mini-halos and active galactic nucleus (AGN) feedback processes from the central galaxy. We find evidence of strong, previously unknown correlations between mini-halo radio power and X-ray cavity power, and between mini-halo and the central galaxy radio power related to the relativistic jets when spectrally decomposing the AGN radio emission into a component for past outbursts and one for ongoing accretion. Overall, our study indicates that mini-halos are directly connected to the central AGN in clusters, following previous suppositions. We hypothesize that AGN feedback may be one of the dominant mechanisms giving rise to mini-halos by injecting energy into the intra-cluster medium and reaccelerating an old population of particles, while sloshing motion may drive the overall shape of mini-halos inside cold fronts. AGN feedback may therefore not only play a vital role in offsetting cooling in cool core clusters, but may also play a fundamental role in re-energizing non-thermal particles in clusters.

The effects of cognitive load on query reformulation: mental demand, temporal demand and frustration

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kyoungsik Na
Keyword(s):  
Cognitive Load ◽  
User Interfaces ◽  
Information Search ◽  
Information Seeking ◽  
Empirical Support ◽  
Query Reformulation ◽  
Content Type ◽  
Mental Demand ◽  
Significant Difference ◽  
Nasa Tlx

PurposeThis study explores the effects of cognitive load on the propensity to reformulate queries during information seeking on the web.Design/methodology/approachThis study employs an experimental design to analyze the effect of manipulations of cognitive load on the propensity for query reformulation between experimental and control groups. In total, three affective components that contribute to cognitive load were manipulated: mental demand, temporal demand and frustration.FindingsA significant difference in the propensity of query reformulation behavior was found between searchers exposed to cognitive load manipulations and searchers who were not exposed. Those exposed to cognitive load manipulations made half as many search query reformulations as searchers not exposed. Furthermore, the National Aeronautical and Space Administration Task Load Index (NASA-TLX) cognitive load scores of searchers who were exposed to the three cognitive load manipulations were higher than those of searchers who were not exposed indicating that the manipulation was effective. Query reformulation behavior did not differ across task types.Originality/valueThe findings suggest that a dual-task method and NASA-TLX assessment serve as good indicators of cognitive load. Because the findings show that cognitive load hinders a searcher's interaction with information search tools, this study provides empirical support for reducing cognitive load when designing information systems or user interfaces.

Recommending Relevant Tutorial Fragments for API-Related Natural Language Questions

2021 ◽  
Vol 31 (09) ◽  
pp. 1251-1275
Author(s):  
Di Wu ◽  
Xiao-Yuan Jing ◽  
Haowen Chen ◽  
Xiaohui Kong ◽  
Jifeng Xuan
Keyword(s):  
Natural Language ◽  
State Of The Art ◽  
Metric Learning ◽  
Application Programming Interface ◽  
Manual Annotation ◽  
Candidate List ◽  
Novel Approach ◽  
Application Programming ◽  
Programming Interface ◽  
Reciprocal Rank

Application Programming Interface (API) tutorial is an important API learning resource. To help developers learn APIs, an API tutorial is often split into a number of consecutive units that describe the same topic (i.e. tutorial fragment). We regard a tutorial fragment explaining an API as a relevant fragment of the API. Automatically recommending relevant tutorial fragments can help developers learn how to use an API. However, existing approaches often employ supervised or unsupervised manner to recommend relevant fragments, which suffers from much manual annotation effort or inaccurate recommended results. Furthermore, these approaches only support developers to input exact API names. In practice, developers often do not know which APIs to use so that they are more likely to use natural language to describe API-related questions. In this paper, we propose a novel approach, called Tutorial Fragment Recommendation (TuFraRec), to effectively recommend relevant tutorial fragments for API-related natural language questions, without much manual annotation effort. For an API tutorial, we split it into fragments and extract APIs from each fragment to build API-fragment pairs. Given a question, TuFraRec first generates several clarification APIs that are related to the question. We use clarification APIs and API-fragment pairs to construct candidate API-fragment pairs. Then, we design a semi-supervised metric learning (SML)-based model to find relevant API-fragment pairs from the candidate list, which can work well with a few labeled API-fragment pairs and a large number of unlabeled API-fragment pairs. In this way, the manual effort for labeling the relevance of API-fragment pairs can be reduced. Finally, we sort and recommend relevant API-fragment pairs based on the recommended strategy. We evaluate TuFraRec on 200 API-related natural language questions and two public tutorial datasets (Java and Android). The results demonstrate that on average TuFraRec improves NDCG@5 by 0.06 and 0.09, and improves Mean Reciprocal Rank (MRR) by 0.07 and 0.09 on two tutorial datasets as compared with the state-of-the-art approach.

Usage of E-Resources by the Faculty Members and PG Students of Kempegowda Institute of Medical Sciences Hospital and Research Centre (KIMS), Bangalore, Karnataka: A Study

2019 ◽  
Vol 9 (2) ◽  
pp. 81-86
Author(s):  
H. M. Shashikala ◽  
S. Srinivasaragavan
Keyword(s):  
Information Search ◽  
Information Seeking ◽  
Vital Role ◽  
Faculty Members ◽  
Health Science ◽  
Research Centre ◽  
Medical Sciences ◽  
Web Based ◽  
Study Results ◽  
Effective Use

Web-based use of E-resources is playing a vital role for information seeking. In this direction the present study was conducted on the use of E-resources (e-books, e-journals, e-databases subscribed by Health Science Library and Information Network, HELINET Consortium and ERMED Consortium) by the faculty members and PG students of Kempegowda Institute of Medical Sciences and Information Centre, Bangalore, Karnataka State. A structured questionnaire was designed and distributed to faculty members and PG students (150) to know their effective use of e-resource for their study, teaching and research. A total of 135 filled in questionnaires were received and the response rate was 82.66%. The study results found that most of the teaching faculty and PG students preferred to search Google and Yahoo as search engine for their information search requirements. At the same time they consulted Pub Med and Science Direct and Ovid publisher’s journal databases to access E- resources.

scholarly journals Parallel Crossed Chaotic Encryption for Hyperspectral Images

2018 ◽  
Vol 8 (7) ◽  
pp. 1183 ◽  
Author(s):  
Carlos Villaseñor ◽  
Eric Gutierrez-Frias ◽  
Nancy Arana-Daniel ◽  
Alma Alanis ◽  
Carlos Lopez-Franco
Keyword(s):  
Chaotic Systems ◽  
Ad Hoc ◽  
State Of The Art ◽  
Hyperspectral Images ◽  
Encryption Algorithm ◽  
Electromagnetic Spectrum ◽  
Chaotic Encryption ◽  
Raw Data ◽  
Essential Tool ◽  
Encryption Schemes

Hyperspectral images (HI) collect information from across the electromagnetic spectrum, and they are an essential tool for identifying materials, recognizing processes and finding objects. However, the information on an HI could be sensitive and must to be protected. Although there are many encryption schemes for images and raw data, there are not specific schemes for HI. In this paper, we introduce the idea of crossed chaotic systems and we present an ad hoc parallel crossed chaotic encryption algorithm for HI, in which we take advantage of the multidimensionality nature of the HI. Consequently, we obtain a faster encryption algorithm and with a higher entropy result than others state of the art chaotic schemes.

scholarly journals Enterprise Business Process Management in the Public Sector: The Case of the Department of Human Services (DHS) Australia

2018 ◽  
Vol 8 (2) ◽  
pp. 217-231 ◽  
Author(s):  
Wasana Bandara ◽  
Scott Bailey ◽  
Paul Mathiesen ◽  
Jo McCarthy ◽  
Chris Jones
Keyword(s):  
Public Sector ◽  
Business Process ◽  
Human Services ◽  
Business Process Management ◽  
Process Management ◽  
Ad Hoc ◽  
Vital Role ◽  
The Public ◽  
Federal Department ◽  
Department Of Human Services

Business process management (BPM) in the public sector is proliferating globally, but has its contextual challenges. Ad hoc process improvement initiatives across governmental departments are not uncommon. However, as for all organisations, BPM efforts that are coordinated across the organisation will reap better outcomes than those conducted in isolation. BPM education plays a vital role in supporting such organisation-wide BPM efforts. This teaching case is focused on the sustainable development and progression of enterprise business process management (E-BPM) capabilities at the Federal Department of Human Services: a large Australian federal government agency. The detailed case narrative vividly describes the case organisation, their prior and present BPM practices and how they have attempted BPM at an enterprise level, capturing pros and cons of the journey. A series of student activities pertaining to E-BPM practices is provided with model answers (covering key aspects of BPM governance, strategic alignment, culture, people, IT, methods, etc.). This case provides invaluable insights into E-BPM efforts in general and BPM within the public sector. It can be useful to BPM educators as a rich training resource and to BPM practitioners seeking guidance for their E-BPM efforts.

scholarly journals Differential Evolution: A Survey and Analysis

2018 ◽  
Vol 8 (10) ◽  
pp. 1945 ◽  
Author(s):  
Tarik Eltaeib ◽  
Ausif Mahmood
Keyword(s):  
Global Optimization ◽  
Differential Evolution ◽  
Optimization Problems ◽  
State Of The Art ◽  
Population Based ◽  
Vital Role ◽  
Fine Tuning ◽  
Control Parameters ◽  
Hybrid Techniques ◽  
Global Optimizer

Differential evolution (DE) has been extensively used in optimization studies since its development in 1995 because of its reputation as an effective global optimizer. DE is a population-based metaheuristic technique that develops numerical vectors to solve optimization problems. DE strategies have a significant impact on DE performance and play a vital role in achieving stochastic global optimization. However, DE is highly dependent on the control parameters involved. In practice, the fine-tuning of these parameters is not always easy. Here, we discuss the improvements and developments that have been made to DE algorithms. In particular, we present a state-of-the-art survey of the literature on DE and its recent advances, such as the development of adaptive, self-adaptive and hybrid techniques.

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