220 research outputs found
A computer vision approach to improve maintenance automation for thermal power plants lubrication systems
No full textPurpose – Lubricating oil leakage is a common issue in thermal power plant operation sites, requiring prompt
equipment maintenance. The real-time detection of leakage occurrences could avoid disruptive consequences
caused by the lack of timely maintenance. Currently, inspection operations are mostly carried out manually,
resulting in time-consuming processes prone to health and safety hazards. To overcome such issues, this paper
proposes a machine vision-based inspection system aimed at automating the oil leakage detection for
improving the maintenance procedures.
Design/methodology/approach – The approach aims at developing a novel modular-structured automatic
inspection system. The image acquisition module collects digital images along a predefined inspection path
using a dual-light (i.e. ultraviolet and blue light) illumination system, deploying the fluorescence of the
lubricating oil while suppressing unwanted background noise. The image processing module is designed to
detect the oil leakage within the digital images minimizing detection errors. A case study is reported to validate
the industrial suitability of the proposed inspection system.
Findings – On-site experimental results demonstrate the capabilities to complete the automatic inspection
procedures of the tested industrial equipment by achieving an oil leakage detection accuracy up to 99.13%.
Practical implications – The proposed inspection system can be adopted in industrial context to detect
lubricant leakage ensuring the equipment and the operators safety.
Originality/value – The proposed inspection system adopts a computer vision approach, which deploys the
combination of two separate sources of light, to boost the detection capabilities, enabling the application for a
variety of particularly hard-to-inspect industrial contexts
Resilience, Leadership and Work Engagement: The Mediating Role of Positive Affect
No full text
This study examines the influence of resilience and transformational leadership on work engagement, and it investigates the mediating effect of positive affect. A total of 422 employees at a large IT company participated the survey. Participants completed established measures of resilience, transformational leadership, positive affect, and work engagement. The results indicate that resilience and transformational leadership are positively related to work engagement. Structural equation modeling analysis shows that positive affect partially mediates the relationships between resilience, transformational leadership, and work engagement. Theoretical contributions, practical implications, and future research directions are discussed.</p
Supplemental Material - Multi-Objective sliding mode control of proton exchange membrane fuel cell system based on adaptive algebraic observer
No full textSupplemental Material for Multi-Objective sliding mode control of proton exchange membrane fuel cell system based on adaptive algebraic observer by Hao Jing, Tiexiong Huang, Cheng Li, Xiaodong Liu, Guangdi Hu and Chaoping Pang in Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy.</p
Graph Encryption for Shortest Path Queries with k Unsorted Nodes
No full textShortest distance queries over large-scale graphs bring great benefits to various applications, i.e., save planning time and travelling expenses. To protect the sensitive nodes and edges in the graph, a user outsources an encrypted graph to an untrusted server without losing the query ability. However, no prior work has considered the user requirement of the shortest path with k unsorted nodes. In particular, we are concerned with how to securely find the shortest path by passing k nodes that do not have a fixed traverse order. To solve the problems, we propose Gespun (stands for Graph encryption for shortest path queries with k unordered nodes). It includes an oracle encryption scheme that is provably secure against the semi-honest server. Specifically, we compute the shortest paths and distances for all nodes locally to obtain path-distance oracles. We transform the shortest paths to a sequence of secure codes by using a pseudo-random permutation to protect the structure privacy. We encrypt the shortest distance by using additively homomorphic encryption. Second, we pack the oracles in link-list nodes and store them in an array-based dictionary after another permutation. Next, we construct a search graph to compute the shortest path while guaranteeing that the path passes the required k nodes. We formally prove that Gespun is adaptively semanticallysecure in the random oracle. We implement a prototype of Gespun and evaluate its performance. Experiments results demonstrate that Gespun is efficient, e.g., a query over 6301 nodes, 20777 edges, and 5 unsorted nodes only needs 483 ms to get queried results. We believe that our research problem span new research that soon promotes a new line of graph encryption schemes
An Improved Distinguisher for Dragon
No full textAbstract. Dragon stream cipher is one of the focus ciphers which have reached Phase 2 of the eSTREAM project. In this paper, we present a new method of building a linear distinguisher for Dragon. The distinguisher is constructed by exploiting the biases of two S-boxes and the modular addition which are basic components of the nonlinear function F. The bias of the distinguisher is estimated to be around 2 −75.32 which is better than the bias of the distinguisher presented by Englund and Maximov. We have shown that Dragon is distinguishable from a random cipher by using around 2 150.6 keystream words and 2 59 memory. In addition, we present a very efficient algorithm for computing the bias of linear approximation of modular addition
A critical look at cryptographic hash function literature
No full textAbstract. The cryptographic hash function literature has numerous hash function definitions and hash function requirements, and many of them disagree. This survey talks about the various definitions, and takes steps towards cleaning up the literature by explaining how the field has evolved and accurately depicting the research aims people have today.
Epidemiology and Outcomes of Acute Kidney Injury in COVID-19 Patients with Acute Respiratory Distress Syndrome: A Multicenter Retrospective Study
No full textBackground: Acute kidney injury (AKI) is associated with increased mortality in patients with acute respiratory distress syndrome (ARDS). However, the epidemiological features and outcomes of AKI among COVID-19 patients with ARDS are unknown. Methods: We retrospectively recruited consecutive adult COVID-19 patients who were diagnosed with ARDS according to Berlin definition from 13 designated intensive care units in the city of Wuhan, China. Potential risk factors of AKI as well as the relation between AKI and in-hospital mortality were investigated. Results: A total of 275 COVID-19 patients with ARDS were included in the study, and 49.5% of them developed AKI during their hospital stay. In comparison with patients without AKI, patients who developed AKI were older, tended to have chronic kidney disease, had higher Sepsis-Related Organ Failure Assessment score on day 1, and were more likely to receive invasive ventilation and develop acute organ dysfunction. Multivariate analysis showe..
Core–Shell Nanocomposites for Improving the Structural Stability of Li-Rich Layered Oxide Cathode Materials for Li-Ion Batteries
No full textThe structural stability
of Li-rich layered oxide cathode materials
is the ultimate frontier to allow the full development of these family
of electrode materials. Here, first-principles calculations coupled
with cluster expansion are presented to investigate the electrochemical
activity of phase-separation, core–shell-structured xLi2MnO3·(1 – x)LiNiCoMnO2 nanocomposites. The detrimental
surface effects of the core region can be countered by the Li2MnO3 shell, which stabilizes the nanocomposites.
The operational voltage windows are accurately determined to avoid
the electrochemical activation of the shell and the subsequent structural
evolution. In particular, the dependence of the activation voltage
with the shell thickness shows that relatively high voltages can still
be obtained to meet the energy density needs of Li-ion battery applications.
Finally, activation energies of Li migration at the core–shell
interface must also be analyzed carefully to avoid the outbreak of
a phase transformation, thus making the nanocomposites suitable from
a structural viewpoint
The Research on Exogenous Problems of Farmers’ Piritual and Cultural Education in China
No full textThe author studied and analyzed the exogenous problems of the farmers’ spiritual and cultural education, and found out: In today’s China, the exogenous problems of the farmers’ spiritual and cultural education mainly reflected in the separation of spiritual and cultural education is from social environment, political system, economic development, and cultural concepts etc. Then the author put forward to the countermeasures and suggestions aimed at optimizing the allocation of famers’ spiritual and cultural educations resources, environment and evaluation system construction and so on
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