scholarly journals Context Definition and Query Language: Conceptual Specification, Implementation, and Evaluation

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1478 ◽  
Author(s):  
Alireza Hassani ◽  
Alexey Medvedev ◽  
Pari Delir Haghighi ◽  
Sea Ling ◽  
Arkady Zaslavsky ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Data Structures ◽  
Query Language ◽  
Contextual Information ◽  
Critical Factor ◽  
Software Components ◽  
Context Management ◽  
Iot Applications ◽  
Research Organizations ◽  
High Level

As IoT grows at a staggering pace, the need for contextual intelligence is a fundamental and critical factor for IoT intelligence, efficiency, effectiveness, performance, and sustainability. As the standardisation efforts for IoT are fast progressing, efforts in standardising context management platforms led by the European Telecommunications Standards Institute (ETSI) are gaining more attention from both academic and industrial research organizations. These standardisation endeavours will enable intelligent interactions between ‘things’, where things could be devices, software components, web-services, or sensing/actuating systems. Therefore, having a generic platform to describe and query context is crucial for the future of IoT applications. In this paper, we propose Context Definition and Query Language (CDQL), an advanced approach that enables things to exchange, reuse and share context between each other. CDQL consists of two main parts, namely: context definition model, which is designed to describe situations and high-level context; and Context Query Language (CQL), which is a powerful and flexible query language to express contextual information requirements without considering details of the underlying data structures. An important feature of the proposed query language is its ability to query entities in IoT environments based on their situation in a fully dynamic manner where users can define situations and context entities as part of the query. We exemplify the usage of CDQL on three different smart city use cases to highlight how CDQL can be utilised to deliver contextual information to IoT applications. Performance evaluation has demonstrated scalability and efficiency of CDQL in handling a fairly large number of concurrent context queries.

scholarly journals Query Rewriting for Incremental Continuous Query Evaluation in HIFUN

Algorithms ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 149
Author(s):  
Petros Zervoudakis ◽  
Haridimos Kondylakis ◽  
Nicolas Spyratos ◽  
Dimitris Plexousakis
Keyword(s):  
Query Optimization ◽  
Query Language ◽  
Computational Cost ◽  
Continuous Queries ◽  
Continuous Query ◽  
Query Rewriting ◽  
Query Evaluation ◽  
Clear Separation ◽  
Complete Dataset ◽  
High Level

HIFUN is a high-level query language for expressing analytic queries of big datasets, offering a clear separation between the conceptual layer, where analytic queries are defined independently of the nature and location of data, and the physical layer, where queries are evaluated. In this paper, we present a methodology based on the HIFUN language, and the corresponding algorithms for the incremental evaluation of continuous queries. In essence, our approach is able to process the most recent data batch by exploiting already computed information, without requiring the evaluation of the query over the complete dataset. We present the generic algorithm which we translated to both SQL and MapReduce using SPARK; it implements various query rewriting methods. We demonstrate the effectiveness of our approach in temrs of query answering efficiency. Finally, we show that by exploiting the formal query rewriting methods of HIFUN, we can further reduce the computational cost, adding another layer of query optimization to our implementation.

scholarly journals When brain damage “improves” perception: neglect patients can localize motion-shifted probes better than controls

2015 ◽  
Vol 114 (6) ◽  
pp. 3351-3358 ◽  
Author(s):  
Stefania de Vito ◽  
Marine Lunven ◽  
Clémence Bourlon ◽  
Christophe Duret ◽  
Patrick Cavanagh ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Visual Fields ◽  
Critical Factor ◽  
Significant Shift ◽  
Stimulus Motion ◽  
Attentional Processes ◽  
Position Shift ◽  
The Right ◽  
High Level ◽  
Better Than

When we look at bars flashed against a moving background, we see them displaced in the direction of the upcoming motion (flash-grab illusion). It is still debated whether these motion-induced position shifts are low-level, reflexive consequences of stimulus motion or high-level compensation engaged only when the stimulus is tracked with attention. To investigate whether attention is a causal factor for this striking illusory position shift, we evaluated the flash-grab illusion in six patients with damaged attentional networks in the right hemisphere and signs of left visual neglect and six age-matched controls. With stimuli in the top, right, and bottom visual fields, neglect patients experienced the same amount of illusion as controls. However, patients showed no significant shift when the test was presented in their left hemifield, despite having equally precise judgments. Thus, paradoxically, neglect patients perceived the position of the flash more veridically in their neglected hemifield. These results suggest that impaired attentional processes can reduce the interaction between a moving background and a superimposed stationary flash, and indicate that attention is a critical factor in generating the illusory motion-induced shifts of location.

Juggling on the line

2015 ◽  
Vol 37 (4) ◽  
pp. 459-474 ◽  
Author(s):  
Samantha Evans
Keyword(s):  
Critical Role ◽  
Case Study Research ◽  
Critical Factor ◽  
Employee Relations ◽  
Front Line ◽  
Structured Interviews ◽  
Line Managers ◽  
Content Type ◽  
Nuanced Understanding ◽  
High Level

Purpose – The purpose of this paper is to examine the interplay between the role of front line managers (FLMs) and their contribution to the reported gap between intended and actual human resource management (HRM). Design/methodology/approach – The findings draw on case study research using 51 semi-structured interviews with managers across two UK retail organisations between 2012 and 2013. Findings – This paper argues that FLMs are key agents in people management and play a critical role in the gap between intended and actual employee relations (ER) and HRM. The research found that these managers held a high level of responsibility for people management, but experienced a lack of institutional support, monitoring or incentives to implement according to central policy. This provided an opportunity for them to modify or resist intended policy and the tensions inherent in their role were a critical factor in this manipulation of their people management responsibilities. Research limitations/implications – The data were collected from only one industry and two organisations so the conclusions need to be considered within these limitations. Practical implications – Efforts to address the gap between intended and actual ER/HRM within organisations will need to consider the role tensions of both front line and middle managers. Originality/value – This research provides a more nuanced understanding of the interplay between FLMs and the gap between intended and actual HRM within organisations. It addresses the issue of FLMs receiving less attention in the HRM-line management literature and the call to research their role in the translation of policy into practice.

A service-oriented context-awareness reasoning framework and its implementation

2018 ◽  
Vol 36 (6) ◽  
pp. 1114-1134 ◽  
Author(s):  
Xiufeng Cheng ◽  
Jinqing Yang ◽  
Lixin Xia
Keyword(s):  
Context Awareness ◽  
Service Providers ◽  
User Behavior ◽  
Contextual Information ◽  
Sensor Data ◽  
Context Information ◽  
Content Type ◽  
Low Level ◽  
Service Oriented ◽  
High Level

PurposeThis paper aims to propose an extensible, service-oriented framework for context-aware data acquisition, description, interpretation and reasoning, which facilitates the development of mobile applications that provide a context-awareness service.Design/methodology/approachFirst, the authors propose the context data reasoning framework (CDRFM) for generating service-oriented contextual information. Then they used this framework to composite mobile sensor data into low-level contextual information. Finally, the authors exploited some high-level contextual information that can be inferred from the formatted low-level contextual information using particular inference rules.FindingsThe authors take “user behavior patterns” as an exemplary context information generation schema in their experimental study. The results reveal that the optimization of service can be guided by the implicit, high-level context information inside user behavior logs. They also prove the validity of the authors’ framework.Research limitations/implicationsFurther research will add more variety of sensor data. Furthermore, to validate the effectiveness of our framework, more reasoning rules need to be performed. Therefore, the authors may implement more algorithms in the framework to acquire more comprehensive context information.Practical implicationsCDRFM expands the context-awareness framework of previous research and unifies the procedures of acquiring, describing, modeling, reasoning and discovering implicit context information for mobile service providers.Social implicationsSupport the service-oriented context-awareness function in application design and related development in commercial mobile software industry.Originality/valueExtant researches on context awareness rarely considered the generation contextual information for service providers. The CDRFM can be used to generate valuable contextual information by implementing more reasoning rules.

scholarly journals Dense RGB-D Semantic Mapping with Pixel-Voxel Neural Network

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 3099 ◽  
Author(s):  
Cheng Zhao ◽  
Li Sun ◽  
Pulak Purkait ◽  
Tom Duckett ◽  
Rustam Stolkin
Keyword(s):  
Point Cloud ◽  
Contextual Information ◽  
Semantic Category ◽  
Semantic Mapping ◽  
Confidence Levels ◽  
Time Performance ◽  
Weighted Fusion ◽  
Geometrical Shapes ◽  
Rgb Images ◽  
High Level

In this paper, a novel Pixel-Voxel network is proposed for dense 3D semantic mapping, which can perform dense 3D mapping while simultaneously recognizing and labelling the semantic category each point in the 3D map. In our approach, we fully leverage the advantages of different modalities. That is, the PixelNet can learn the high-level contextual information from 2D RGB images, and the VoxelNet can learn 3D geometrical shapes from the 3D point cloud. Unlike the existing architecture that fuses score maps from different modalities with equal weights, we propose a softmax weighted fusion stack that adaptively learns the varying contributions of PixelNet and VoxelNet and fuses the score maps according to their respective confidence levels. Our approach achieved competitive results on both the SUN RGB-D and NYU V2 benchmarks, while the runtime of the proposed system is boosted to around 13 Hz, enabling near-real-time performance using an i7 eight-cores PC with a single Titan X GPU.

scholarly journals NORMALIZATION IN DATABASE DESIGN

2018 ◽  
Vol 4 (1) ◽  
pp. 34
Author(s):  
Zainul Efendy
Keyword(s):  
Data Structures ◽  
Query Language ◽  
Database Design ◽  
Simple Solution ◽  
Transaction Model ◽  
Model Form

This research is done to find a simple solution how to find a normalization techniques are appropriate in database design, normalization techniques has several steps of which are forms of abnormal, normalization first, normalization 2st and normalization 3st, only 3 stages rare to be discussed in this study, as in lectures often find their students do not understand to implement this normalization techniques. The results of this study include determining the database data structures, forming sql (structural query language) by using MySQL DBMS and prototype transaction model form.

scholarly journals High Sucrose Levels and Abnormal Enzyme Activity as a Function of Nutritional Stress in Sugarcane

1969 ◽  
Vol 51 (4) ◽  
pp. 325-333
Author(s):  
Alex G. Alexander
Keyword(s):  
Nutrient Deficiency ◽  
Critical Factor ◽  
Nutritional Stress ◽  
Nutrient Supply ◽  
Oxidative Enzymes ◽  
Sand Culture ◽  
High Level ◽  
To Receive ◽  
High Sucrose ◽  
Nitrogen Phosphorus

Deficiencies of nitrogen, phosphorus, potassium, and calcium were gradually induced in sugarcane grown by sand culture. There were three objectives: 1, To determine whether nutritional stress in general is a means of inducing higher sucrose production; 2, to determine whether sucrose increases can be triggered without reaching nutrient-deficiency levels which would reduce tonnage; and 3, to ascertain whether increased sucrose production can be traced to common behavior patterns of hydrolytic and oxidative enzymes. All plants received a moderately high level of all nutrients until 14 weeks of age. Thereafter, individual nutrients were gradually lowered at intervals of 2 weeks, while control plants continued to receive the original levels. All plants subjected to nutritional stress accumulated higher leaf sucrose than control plants, regardless of the nutrient withheld. In each instance sucrose increases were recorded before nutrient supply had reached deficiency proportions. General nutritional stress thus appears to trigger variations in sugar level, with nutritional imbalance rather than actual deficiency being a critical factor. All plants under nutritional stress revealed a concurrent suppression of amylase as sucrose increased. Peroxidase was greatly stimulated by all nutritional treatments. Phosphatase was suppressed by decreasing nitrate and phosphorus, but was generally unaffected by the potassium and calcium treatments. Several distinct mechanisms of increased sucrose formation are indicated by the enzyme data. Sensitivity of amylase to changing nutrient supply is discussed from the standpoint of a possible indicator of approaching deficiency.

Prototyping an autonomous delivery vehicle

2018 ◽  
Vol 66 (2) ◽  
pp. 160-182
Author(s):  
Benjamin C. Heinrich ◽  
Thorsten Luettel ◽  
Dennis Fassbender ◽  
Patrick Burger ◽  
Felix Ebert ◽  
...  
Keyword(s):  
Test Facility ◽  
Sensor Calibration ◽  
Software Components ◽  
Delivery Vehicle ◽  
Planning And Control ◽  
Custom Made ◽  
Position And Orientation ◽  
High Level ◽  
Control Modules ◽  
And Control

AbstractIn this paper, we describe the hardware and software components of a fully autonomous prototype delivery vehicle. Equipped with a robotic arm, the demonstrator is capable of delivering packages and picking up new ones by interacting with custom-made delivery boxes. As highly accurate positioning w. r. t. a box is required for successful handover of packages, we track the pose (position and orientation) of the box using a high-resolution on-board camera. The resulting estimate is relayed to our planning and control modules, which ensure that the vehicle reaches its required pose with centimeter-level accuracy.In order to deliver packages, the car needs to autonomously navigate our test facility, avoiding static and dynamic obstacles while obeying simple traffic rules. As one focus is on the practical challenges encountered when building a prototype, we cover issues ranging from sensor calibration and system identification to perception, planning, control, and the implementation of high-level behaviors. While some of the proposed solutions to these problems are not necessarily novel, they allowed us to demonstrate the vehicle’s capabilities after a development phase of less than 12 months.

Graph analytics and visualization for cyber situational understanding

2021 ◽  
pp. 154851292110513
Author(s):  
Steven Noel ◽  
Stephen Purdy ◽  
Annie O’Rourke ◽  
Edward Overly ◽  
Brianna Chen ◽  
...  
Keyword(s):  
Natural Language ◽  
Detailed Analysis ◽  
Ad Hoc ◽  
Query Language ◽  
Software Components ◽  
Proof Of Concept ◽  
Graph Analytics ◽  
The Core ◽  
Interactive Visualizations ◽  
Graph Queries

This paper describes the Cyber Situational Understanding (Cyber SU) Proof of Concept (CySUP) software system for exploring advanced Cyber SU capabilities. CySUP distills complex interrelationships among cyberspace entities to provide the “so what” of cyber events for tactical operations. It combines a variety of software components to build an end-to-end pipeline for live data ingest that populates a graph knowledge base, with query-driven exploratory analysis and interactive visualizations. CySUP integrates with the core infrastructure environment supporting command posts to provide a cyber overlay onto a common operating picture oriented to tactical commanders. It also supports detailed analysis of cyberspace entities and relationships driven by ad hoc graph queries, including the conversion of natural language inquiries to formal query language. To help assess its Cyber SU capabilities, CySUP leverages automated cyber adversary emulation to carry out controlled cyberattack campaigns that impact elements of tactical missions.

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