Wyniki wyszukiwania dla: COMMON CAUSE FAILURES - MOST Wiedzy

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Wyniki wyszukiwania dla: COMMON CAUSE FAILURES

Wyniki wyszukiwania dla: COMMON CAUSE FAILURES

  • Induction motor bearings diagnostic indicators based on MCSA and normalized triple covariance

    Publikacja

    - Rok 2017

    Induction motors are one of the most widely used electrical machines. Statistics of bearing failures of induction motors indicate, that they constitute more than 40% of induction motor damage. Therefore, bearing diagnosis is so important for trouble-free work of induction motors. The most common methods of bearing diagnosis are based on vibration signal analysis. The main disadvantage of those methods is the need for physical access...

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  • Landscape of Automated Log Analysis: A Systematic Literature Review and Mapping Study

    Publikacja

    - IEEE Access - Rok 2022

    Logging is a common practice in software engineering to provide insights into working systems. The main uses of log files have always been failure identification and root cause analysis. In recent years, novel applications of logging have emerged that benefit from automated analysis of log files, for example, real-time monitoring of system health, understanding users’ behavior, and extracting domain knowledge. Although nearly every...

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  • Service-based Resilience for Embedded IoT Networks

    Publikacja

    - Rok 2020

    Embedded IoT networks are the backbone of safety-critical systems like smart factories, autonomous vehicles, and airplanes. Therefore, resilience against failures and attacks should be a prior concern already in their design stage. In this study, we introduce a service-based network model as an MILP optimization problem for the efficient deployment of a service overlay to the embedded network by meeting QoS and resilience requirements....

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  • Improving the Survivability of Carrier Networks to Large-Scale Disasters

    Publikacja
    • A. de Sousa
    • J. Rak
    • F. Barbosa
    • D. Santos
    • D. Mehta

    - Rok 2020

    This chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...

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  • Krzysztof Goczyła prof. dr hab. inż.

    Krzysztof Goczyła, profesor zwyczajny Politechniki Gdańskiej, informatyk, specjalista z inżynierii oprogramowania, inżynierii wiedzy i baz danych. Ukończył studia wyższe na  Wydziale Elektroniki Politechniki Gdańskiej w 1976 r. jako magister inżynier elektronik w specjalności automatyka. Na Politechnice Gdańskiej pracuje od 1976. Na Wydziale Elektroniki PG w 1982 r. uzyskał doktorat z informatyki, a w 1999 r. habilitację. W 2012...

  • Bridge Ergonomic Design: A Review

    Human error remains the most common cause of marine incidents and it is worth emphasizing that navigator’s performance is directly affected by ergonomic factors on the bridge. Studies regarding influence of bridge design and work environment on the operator are rare, thus the main purpose of this paper is to fill in this gap. Documents issued by recognized organizations, research publications and additional sources were reviewed...

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  • Network Graph Transformation Providing Fast Calculation of Paths for Resilient Routing

    Publikacja

    Protection of transmission against failures can be appropriately dealt with by alternative paths. However, common schemes (e.g., Bhandaris scheme) are characterized by a remarkable delay while determining the transmission paths. This in turn may have a serious impact on serving dynamic demands (characterized by relatively short duration time). As a remedy to this problem, we introduce an approach to pre-compute the sets of disjoint...

  • INTER-LAYER SHARING OF BACKUP PATH CAPACITIES PROVIDING FAST SERVICE RECOVERY IN IP-MPLS/WDM NETWORKS

    Publikacja

    - Rok 2013

    In this paper, we investigate the issue of providing the transmission continuity in IP-MPLS/WDM networks in the presence of failures of nodes/links. Special focus is put on assuring fast restoration of flows affected after a failure in a scenario assuming sharing the backup path capacities in order to decrease the overall bandwidth consumption. In particular, we propose a new approach to inter-layer sharing of link capacity reserved...

  • Paweł Burdziakowski dr inż.

    dr inż. Paweł Burdziakowski jest specjalista w zakresie fotogrametrii i teledetekcji lotniczej niskiego pułapu, nawigacji morskiej i lotniczej. Jest również licencjonowanym instruktorem lotniczym oraz programistą. Głównymi obszarami zainteresowania jest fotogrametria cyfrowa, nawigacja platform bezzałogowych oraz systemy bezzałogowe, w tym lotnicze, nawodne, podwodne. Prowadzi badania  w zakresie algorytmów i metod poprawiających...

  • Service-based Resilience via Shared Protection in Mission-critical Embedded Networks

    Publikacja

    Mission-critical networks, which for example can be found in autonomous cars and avionics, are complex systems with a multitude of interconnected embedded nodes and various service demands. Their resilience against failures and attacks is a crucial property and has to be already considered in their design phase. In this paper, we introduce a novel approach for optimal joint service allocation and routing, leveraging virtualized...

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  • A new assay based on terminal restriction fragment length polymorphism of homocitrate synthase gene fragments for Candida species identification

    Publikacja

    - JOURNAL OF APPLIED GENETICS - Rok 2017

    Candida sp. have been responsible for an increasing number of infections, especially in patients with immunodeficiency. Species specific differentiation of the Candida sp. is difficult in routine diagnosis. This identification can have a highly significant association in therapy and prophylaxis. This work has shown a new application of terminal restriction fragment length polymorphism (t-RFLP) method in molecular identification...

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  • Joint fingerprinting and decryption method for color images based on quaternion rotation with cipher quaternion chaining

    This paper addresses the problem of unauthorized redistribution of multimedia content by malicious users (pirates). In this method three color channels of the image are considered a 3D space and each component of the image is represented as a point in this 3D space. The distribution side uses a symmetric cipher to encrypt perceptually essential components of the image with the encryption key and then sends the encrypted data via...

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  • Evaluation of time-efficiency of disjoint paths calculation schemes

    Publikacja

    - Rok 2015

    The concept of alternate paths has been shown in the literature to provide fast response of a network to failures of its elements (nodes/links) affecting flows along the primary communication paths. Various approaches have been proposed to reduce the time necessary to redirect the respective flows onto the alternate paths. In this paper, we focus on another important objective, that so far has not received much attention, i.e.,...

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  • Jan Daciuk dr hab. inż.

    Jan Daciuk uzyskał tytuł zawodowy magistra na Wydziale Elektroniki Politechniki Gdańskiej w 1986 roku, a doktorat na wydziale Elektroniki, Telekomunikacji i Informatyki PG w 1999. Pracuje na Wydziale od 1988 roku. Jego zainteresowania naukowe obejmują zastosowania automatów skończonych w  przetwarzaniu języka naturalnego i przetwarzaniu mowy. Spędził ponad cztery lata w europejskich uniwersytetach i instytutach naukowych, takich...

  • Future research directions in design of reliable communication systems

    Publikacja
    • J. Rak
    • M. Pickavet
    • K. S. Trivedi
    • J. A. Lopez
    • A. M. C. A. Koster
    • J. P. Sterbenz
    • E. Çetinkaya
    • T. Gomes
    • M. Gunkel
    • K. Walkowiak
    • D. Staessens

    - TELECOMMUNICATION SYSTEMS - Rok 2015

    In this position paper on reliable networks, we discuss new trends in the design of reliable communication systems. We focus on a wide range of research directions including protection against software failures as well as failures of communication systems equipment. In particular, we outline future research trends in software failure mitigation, reliability of wireless communications, robust optimization and network design, multilevel...

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  • Peptidoglycan hydrolases - potential weapons against Staphylococcus aureus

    Bacteria of the genus Staphylococcus are common pathogens responsible for a broad spectrum of human and animal infections and belong to most important etiological factors causing food poisoning. Because of rapid increase in prevalence of isolation of staphylococci resistant to many antibiotics, there is an urgent need for development of new alternative chemotherapeutics. A number of studies have recently demonstrated the strong...

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  • Structure of own costs of private universities in 2010

    Dane Badawcze
    open access

    The biggest costs are generated by basic teaching activities. However, in the context of the competitiveness and quality of education in private universities, research expenditure is a cause for concern. Dataset shows that these universities spend less than 4.0% on research compared to other activities. For comparison, in public universities research...

  • Knowledge-based functional safety management using ProSIL software

    In the article the ProSIL software for computer aided functional safety management is presented. The software consists of three modules for the determination of the required SIL level (ProSILen) and verification of the SIL level (ProSILver). In the ProSIL the calibrated knowledge-based risk graph method for determining the required safety integrity level (SIL) of the safety functions identified in hazard analysis is implemented....

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  • Toward Fast Calculation of Communication Paths for Resilient Routing

    Publikacja

    - NETWORKS - Rok 2017

    Utilization of alternate communication paths is a common technique to provide protection of transmission against failures of network nodes/links. However, a noticeable delay is encountered when calculating the relevant sets of disjoint paths using the available algorithms (e.g., using Bhandari’s approach). This, in turn, may have a serious impact on the ability of a network to serve dynamic demands...

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  • HCI-Based Wireless System for Measuring the Concentration of Mining Machinery and Equipment Operators

    Publikacja

    - Applied Sciences-Basel - Rok 2023

    Maintaining stable and reliable working conditions is a matter of vital importance for various companies, especially those involving heavy machinery. Due to human exhaustion, as well as unpredicted hazards and dangerous situations, the personnel has to take actions and wisely plan each move. This paper presents a human–computer interaction (HCI)-based system that uses a concentration level measurement function to increase the safety...

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  • Failure model of main elements of the ship engine crankshaft-piston assembly

    Publikacja

    The paper presents a failure model of main elements of the crankshaft-piston assembly, based on failures ofcrankshaft-piston assembly and timing gear system of the Sulzer RD engines, retrieved from the equipment reliabilitydata of selected ships.

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  • Providing Differentiated Levels of Service Availability in VANET Communications

    Publikacja

    Inter-vehicle communications seems to be a promising remedy not only for a number of road-safety issues, but also to improve the efficiency of road traffic, as well as to support the on-board infotainment applications. However, it often encounters disruptions due to high mobility of vehicles causing frequent failures of communication links. In this paper, we utilize the idea of multipath vehicle-to-vehicle routing to provide protection...

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  • eFRADIR: An Enhanced FRAmework for DIsaster Resilience

    Publikacja
    • A. Pasic
    • R. Girao-Silva
    • F. Mogyorosi
    • B. Vass
    • T. Gomes
    • P. Babarczi
    • P. Revisnyei
    • J. Tapolcai
    • J. Rak

    - IEEE Access - Rok 2021

    This paper focuses on how to increase the availability of a backbone network with minimal cost. In particular, the new framework focuses on resilience against natural disasters and is an evolution of the FRADIR/FRADIR-II framework. It targets three different directions, namely: network planning, failure modeling, and survivable routing. The steady state network planning is tackled by upgrading a sub-network (a set of links termed...

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  • Application of Game Theory to Conflict Management in a Construction Contract

    Interest has recently grown in the application of game theory (GT) to solve a number of diverse problems in the field of construction. The use of GT by a general contractor (GC) of construction works to indicate the best strategy leading to winning court proceedings in a situation of conflict with investor (IN), has not been investigated until now. Thus the aim of this paper is to indicate the optimal strategy from the GC viewpoint...

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  • Practical issues for the implementation of survivability and recovery techniques in optical networks

    Publikacja
    • G. Ellinas
    • D. Papadimitriou
    • J. Rak
    • D. Staessens
    • J. P. Sterbenz
    • K. Walkowiak

    - Optical Switching and Networking - Rok 2014

    Failures in optical networks are inevitable. They may occur during work being done for the maintenance of other infrastructures, or on a larger scale as the result of an attack or large-scale disaster. As a result, service availability, an important aspect of Quality of Service (QoS), is often degraded. Appropriate fault recovery techniques are thus crucial to meet the requirements set by the Service Level Agreements (SLAs) between...

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  • Instantaneous power signal measurements for bearing diagnostics

    Dane Badawcze

    Bearing diagnostics can be carried out based on the method, which relies on the measurement and analysis of the variability of the signal instantaneous power, defined as the product of instantaneous current and voltage power supplied to the engines. Bearing damage causes the appearance of deformations, which are in the form of additional harmonic components...

  • Analysis of the instantaneous power signal for bearing diagnostics -bearing damaged

    Dane Badawcze

    The attached dataset contains the measurement results of the instantaneous values of current and voltage, recorded during the diagnostics of a damaged bearing. Bearing diagnostics can be carried out based on the method, which relies on the measurement and analysis of the variability of the signal instantaneous power, defined as the product of instantaneous...

  • Molecular targets for antifungals in amino acid and protein biosynthetic pathways

    Publikacja

    Fungi cause death of over 1.5 million people every year, while cutaneous mycoses are among the most common infections in the world. Mycoses vary greatly in severity, there are long-term skin (ringworm), nail or hair infections (tinea capitis), recurrent like vaginal candidiasis or severe, life-threatening systemic, multiorgan infections. In the last few years, increasing importance is attached to the health and economic problems...

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  • A MEASUREMENT SYSTEM FOR MONITORING CARDIOVASCULAR EVENTS IN SYNCOPE PATIENTS

    Publikacja

    Syncope phenomena is an abrupt and transient loss of consciousness leading to interruption of awareness of one’s surroundings and falls with risk of injury. Syncope is often followed by complete and usually rapid spontaneous recovery. It is said that half of all individuals experience syncopal event at least once during their life. The condition can occur at any age and happens in people with and without other medical problems....

  • Virulence gene profiles in Staphylococcus aureus isolated from cows with subclinical mastitis in eastern Poland

    Publikacja
    • B. Kot
    • P. Szweda
    • A. Frankowska-maciejewska
    • M. Piechota
    • K. Wolska

    - JOURNAL OF DAIRY RESEARCH - Rok 2016

    Staphylococcus aureus is arguably the most important pathogen involved in bovine mastitis. The aim of this study was to determine the virulence gene profiles of 124 Staph. aureus isolates from subclinical mastitis in cows in eastern Poland. The presence of 30 virulence genes encoding adhesins, proteases and superantigenic toxins was investigated by PCR. The 17 different combinations of adhesin genes were identified. Occurrence...

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  • Dagmara Nikulin dr

    Dagmara Nikulin jest zatrudniona na Wydziale Zarządzania i Ekonomii na stanowisku adiunkta badawczo-dydaktycznego od 2014 roku. Początkowo pracowała w Katedrze Nauk Ekonomicznych, a obecnie w Katedrze Statystyki i Ekonometrii. Jest absolwentką Wydziału Ekonomii Uniwersytetu Ekonomicznego w Poznaniu (2009) oraz Wydziału Nauk Społecznych Uniwersytetu im. Adama Mickiewicza w Poznaniu (2010). W latach 2006-2007 studiowała na uniwersytecie...

  • Checkpointing of Parallel MPI Applications using MPI One-sided API with Support for Byte-addressable Non-volatile RAM

    Publikacja

    - Rok 2016

    The increasing size of computational clusters results in an increasing probability of failures, which in turn requires application checkpointing in order to survive those failures. Traditional checkpointing requires data to be copied from application memory into persistent storage medium, which increases application execution time as it is usually done in a separate step. In this paper we propose to use emerging byte-addressable...

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  • Load effect impact on the exploitation of concrete machine foundations used in the gas and oil industry

    Publikacja

    - Rok 2019

    Machine foundations is a critical topic in the gas and oil industry, which design and exploitation require extensive technical knowledge. Machine foundations are the constructions which are intended for mounting on it a specific type of machine. The foundation has to transfer dynamic and static load from machine to the ground. The primary difference between machine foundations and building foundations is that the machine foundations...

  • Posttraumatic Orbital Emphysema: A Numerical Model

    Publikacja

    - Journal of Ophthalmology - Rok 2014

    Orbital emphysema is a common symptom accompanying orbital fracture. The pathomechanism is still not recognized and the usually assumed cause, elevated pressure in the upper airways connected with sneezing or coughing, does not always contribute to the occurrence of this type of fracture. Observations based on the finite model (simulating blowout type fracture) of the deformations of the inferior orbital wall after a strike in...

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  • Mechanisms for supporting electric vehicle purchasers in selected European countries in 2011-2016

    Dane Badawcze
    open access

    The European authorities have not developed a single common preference model for electric car buyers within the Union. Different countries have decided on different solutions. The following dataset presents mechanisms for supporting electric vehicle purchasers in selected European countries in years 2011-2016, including both economical (in the form...

  • Comparative wear test of journal sliding bearings with sintered bronze and Babbitt alloy bushes lubricated by environmentally acceptable/adapted lubricants (EAL)

    Publikacja

    A growing awareness of the negative effects of mineral oils on the natural environment has resulted in the introduction of new regulations related to environmental protection. One of these regulations requires the use of environmentally acceptable/adapted lubricants (EAL) to lubricate marine main shaft bearings, in place of the mineral lubricating oils that have been used for decades. Classification Societies, which supervise...

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  • An approach to improve the time efficiency of disjoint paths calculation

    Publikacja

    - Rok 2015

    Failures of network elements can be appropriately dealt with by utilization of alternate disjoint paths to provide redirection of flows affected by failures of the respective working paths. Known approaches can be broadly divided by decision on backup paths installation into proactive and reactive mechanisms, as well as based on the scope of recovery actions into local and global rerouting. There are several important scenarios...

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  • Geographic Information System for Flood Hazard Analysis and Early Warning Using Numerical Weather Predictions

    Publikacja

    - Rok 2015

    Floods are a phenomenon which causes significant losses of lives as well as property damage, which in turn severely impact the local economy. The nature of a flooding has been well researched, and several methods of flood hazard simulation have been established over the last decades. The current legislation in the European Union requires the Member States to create, maintain and update flood risk and hazard maps, as well as identify...

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  • Gdańsk University of Technology graduates’ forms of raising qualifications – years 2017-2018

    Dane Badawcze
    open access

    The dataset includes data from the survey on the Gdańsk University of Technology graduates' from the years 2017-2018 on the forms of raising their qualifications. The survey was conducted in the period from 2019 to 2020, two years after the respondents obtained graduate status. The research sample included 2909 respondents. To summarize, the most common...

  • Gdańsk University of Technology graduates’ forms of raising qualifications – years 2011-2016

    Dane Badawcze
    open access

    The dataset includes data from the survey on the Gdańsk University of Technology graduates' from the years 2011-2016 on the forms of raising their qualifications. The survey was conducted in the period from 2013 to 2018, two years after the respondents obtained graduate status. The research sample included 9525 respondents. To summarize, the most common...

  • Phoenixin-14 effect on viability and THBS2 and CDH1 expression in 12Z endometriosis cell line

    Dane Badawcze
    open access
    • K. Kulińska
    • M. Wierzbicka
    • M. Andrusiewicz
    • M. Wołuń-Cholewa

    Phoenixin-14 is a neuropeptide produced by the paraventricular nuclei of the anterior hypothalamus that regulates reproductive system functions. Its level in patients with endometriosis is reduced and may be the cause of dysregulated HPG-axis. Our study tested endometriosis-specific concentrations of PNX-14 on endometrial epithelial cell line 12Z in...

  • Risk factor assessment in agricultural supply chain by fuzzy logic

    Publikacja

    - Rok 2024

    Significant uncertainty characterizes the harvest period. This aspect is due to various risks impacting agrifood supply chains. The occurrence of risks is due to hazards: technological failures, technical breakdowns, or adverse weather conditions. Hence, the operational time of the agricultural supply chain during the harvest period increases due to such risk factors. In essence, some hazards are fuzzy, and the nature of most threats...

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  • Using Long-Short term Memory networks with Genetic Algorithm to predict engine condition

    Publikacja

    - Gazi University Journal of Science - Rok 2022

    Predictive maintenance (PdM) is a type of approach for maintenance processes, allowing maintenance actions to be managed depending on the machine's current condition. Maintenance is therefore carried out before failures occur. The approach doesn’t only help avoid abrupt failures but also helps lower maintenance cost and provides possibilities to manufacturers to manage maintenance budgets in a more efficient way. A new deep neural...

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  • Monitoring of a historic sacral building on an example Basilica St. Nicholas in Gdańsk

    he paper describes the case of monitoring the technical condition of a historic sacral building after a failure and during renovation works. In order to monitor the condition of the building, safely conduct diagnostic work, identify the causes of failures andsafely carry out renovation works, a detailed Facility Monitoring Program has been developed, which has been implemented, is operational and is a source of valuable data used...

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  • Resilient Routing in Communication Networks

    Publikacja

    - Rok 2015

    This important text/reference addresses the latest issues in end-to-end resilient routing in communication networks. The work highlights the main causes of failures of network nodes and links, and presents an overview of resilient routing mechanisms, covering issues related to the Future Internet (FI), wireless mesh networks (WMNs), and vehicular ad-hoc networks (VANETs). For each of these network architectures, a selection of...

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  • Cross-border transmission line configuration influence on the electrical power and energy billing process

    In 2015 a connection between the Polish and Lithuanian power systems become fully operational. The connection consists of a 400 kV double circuit transmission line and a back-to-back HVDC substation located on the Lithuanian side. A magnetic couplings between the circuits of the transmission line cause that during power transmission a different values of active power losses are observed in both circuits. This situation may cause...

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  • D-loop sequences retrieved from Canis lupus familiaris mitochondrial genome

    Dane Badawcze
    open access
    • K. Kowal
    • B. Ślaska
    • A. Tkaczyk-Wlizło

    Canine mitochondrial genome is built of 16727 bp. Non-coding control region (mtCR), called also D-loop, begins with 15458 nucleotide and ends with 16727 nucleotide. The length of this fragment is 1270 bp (Kim et al., 1998). D-loop region is responsible for replication and transcription of mitochondrial DNA. Mutations that occur within it may cause irregularity...

  • Should we seek further improvement of fluid film bearings - what for and how?

    Publikacja

    - Rok 2013

    Fluid film bearings have been extensively used in the industry because of their unbeatable durability and extremely low friction coefficient. Large bearings supporting shafts of huge and important rotating machines constitute a special group of fluid film bearings since the reliability of crucial systems, like for example electro-energetic system, rely on their trouble-free operation. Large thrust bearings, apart from enormous...

  • Investigating the disease- modifying properties of sclerotiorin in Alzheimer's therapy using acetylcholinesterase inhibition

    Publikacja

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder caused due to the damage and loss of neurons in specific brain regions. It is the most common form of dementia observed in older people. The symptoms start with memory loss and gradually cause the inability to speak and do day-to-day activities. The cost of caring for those affected individuals is huge and is probably beyond most developing countries capability....

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  • Regulated Assembly of LPS, Its Structural Alterations and Cellular Response to LPS Defects

    Distinguishing feature of the outer membrane (OM) of Gram-negative bacteria is its asymmetry due to the presence of lipopolysaccharide (LPS) in the outer leaflet of the OM and phospholipids in the inner leaflet. Recent studies have revealed the existence of regulatory controls that ensure a balanced biosynthesis of LPS and phospholipids, both of which are essential for bacterial viability. LPS provides the essential permeability...

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