Filters
total: 1792
filtered: 1321
-
Catalog
Chosen catalog filters
displaying 1000 best results Help
Search results for: WEATHER ROUTING, WEATHER HAZARD AVOIDANCE, MULTICRITERIA WEATHER ROUTING, WEATHER CONDITION, SPEA ALGORITHM, HYBRID PROPULSIONS, MOTOR-DRIVEN SHIP, SHIP SAFETY MEASURE
-
Hazard Control in Industrial Environments: A Knowledge-Vision-Based Approach
PublicationThis paper proposes the integration of image processing techniques (such as image segmentation, feature extraction and selection) and a knowledge representation approach in a framework for the development of an automatic system able to identify, in real time, unsafe activities in industrial environments. In this framework, the visual information (feature extraction) acquired from video-camera images and other context based gathered...
-
Speed sensorless ac drive with inverter output filter and fault detection using load torque signal
PublicationIn this paper, a sensorless induction motor (IM) drive using speed observer system is presented. The system includes load torque computation for gear fault detection. Nonlinear control method is adopted for controlling the motor over a wide speed range. An LC filter for smoothing current and voltage waveforms is used at the output of the voltage inverter. The use of filter imposes more building of the used observer to avoid using...
-
AC-DC-DC Converter for Small Power Energy Storage Systems
PublicationThe energy transformation driven by the development of renewable energy sources has become a reality for all power grid users. Prosumer energy, primarily utilizing photovoltaic installations, is one of the fastest-growing market segments. The advancement of technology, a decrease in electrochemical energy storage prices, and changes in the legal framework governing energy billing for grid-fed power have led to a growing interest...
-
Damage Control in Warships
PublicationAs a result of dynamic quantitative and qualitative developments in the maritime industry its participants face harder and harder challenges pertaining to safety of ships and navigation. Practice has shown that even very well organised fleets are harassed by emergencies and accidents that can be neither predicted nor absolutely avoided. In order to counter the occuring emergencies and accidents, and to minimize their effects damage...
-
Wyznaczenie obciążeń na poszycie okrętu wywołanych uderzeniem fal i uderzeniem w lód i ich wpływ na bezpieczeństwo okrętu
PublicationThe main problem is the vessels rather accurate determination of the hydrodynamic loads so-called hydroelasticity outside . This can be done by theoretical analysis , computer simulation or by experiment. This gives the hydrodynamic pressure distribution on the walls of the ship's hull and also on the walls of marine vessels .The most dangerous are the impact of extreme storm waves , the impact of the wharf and the impact zone...
-
Selected dynamic properties of adaptive proportional observer of induction motor state variables
PublicationThis paper presents problems related to the design and the stability of adaptive proportional observer which is used for estimation of magnetic flux and motor speed in sensorless control systems of induction motor. The gain matrix of the observer was chosen by genetic algorithm and alternatively by pole placement method. It has been shown that adaptive proportional observer is stable if the...
-
Indirect Measurement of Motor Current Derivatives in PMSM Sensorless Drives
PublicationMotor current derivatives contain useful information for control algorithms, especially in sensorless electric drives. The measurement of motor current derivatives in electric motors supplied by voltage source inverter can be performed using di/dt transducers. However, in such a solution additional sensors have to be installed, e.g. Rogowski coils. Another approach is to measure current derivatives indirectly – by oversampling...
-
Towards the boundary between easy and hard control problems in multicast Clos networks
PublicationIn this article we study 3-stage Clos networks with multicast calls in general and 2-cast calls, in particular. We investigate various sizes of input and output switches and discuss some routing problems involved in blocking states. To express our results in a formal way we introduce a model of hypergraph edge-coloring. A new class of bipartite hypergraphs corresponding to Clos networks is studied. We identify some polynomially...
-
Protection System Design of Induction Motor for Industries
PublicationThe fundamental and durable structures of induction motor, as well as their low manufacturing cost, make them popular components in a wide range of current applications. Providing a safety net for employees is a must-have for businesses. This project’s motivation for improvement is to provide industrial motors, lift motors, pumps, and so on with safety. An induction motor’s primary goal is to protect it from problems, such as...
-
Protection System Design of Induction Motor for Industries
PublicationThe fundamental and durable structures of induction motor, as well as their low manufacturing cost, make them popular components in a wide range of current applications. Providing a safety net for employees is a must-have for businesses. This project’s motivation for improvement is to provide industrial motors, lift motors, pumps, and so on with safety. An induction motor’s primary goal is to protect it from problems, such as...
-
Towards Knowledge Formalization and Sharing in a Cognitive Vision Platform for Hazard Control (CVP-HC)
PublicationHazards are present in all workplaces and can result in serious injuries, short and long-term illnesses, or death. In this context, management of safety is essential to ensure the occupational health of workers. Aiming to assist the safety manage-ment process, especially in industrial environments, a Cognitive Vision Platform for Hazard Control (CVP-HC) has been proposed. The CVP-HC is a scalable yet adaptable system capable of...
-
Analysis of bisphenols and their derivatives in infant and toddler ready-to-feed milk and powdered milk by LC MS/MS
PublicationReady-to-feed milk and powdered milk packed in different types of packaging lined with resin are chosen as the primary or complementary diet for infants and toddlers. An HPLC–MS/MS method was established and validated for the determination of nineteen bisphenols and their derivatives in such samples. The recoveries were from 31% to 120%, while the values of limit of detection and quantification were in the range of 0.24–0.40 and...
-
Review of Selected Methods for Prediction of Added Resistance in Following Waves
PublicationThe added resistance in waves is a mean value of non-linear, second order reaction of a ship to incoming waves. In the beginning of the 20th century, the experimental methods for investigation of ship hydrodynamics at model scale were developed. They allowed the evaluation of added resistance by measurements in irregular waves (directly) or by measurements in regular waves (in-direct method). The main goal was to find more precise...
-
Improvement of ships seakeeping performance by application of the full-scale cfd simulations
PublicationThe ship’s fuel economy is increasingly important. The paper presents the effect of redesigning a case study ship for increasing seakeeping performance. Selected wave parameters reflect very difficult operational conditions existing on the North Sea and the Baltic Sea. The analyzed variants of a case study ship represent the latest developments of modern hull forms. The concepts similar to V-shaped bulbous bow, X-bow, X-aft, B-bow...
-
SafeCity – a GIS-based tool profiled for supporting decision making in urban development and infrastructure protection
PublicationThis paper presents a system for analysis of municipal Critical Infrastructures, which offers integrated tools for target analysis, hazard scenario simulations and spatial analysis within a remotely accessible Web-based Geographic Information System. The system has been applied to research conducted in the city of Gdansk with the aid of blast attack, chemical leakage and flood hazard scenarios, as well as a spatial density algorithm,...
-
Selected acoustic images of the Gdansk Bay
PublicationThe main goal of the paper is to describe the results of sounding the Gdansk Bay seabed by using a parametric sub-bottom profiler, multibeam echosounder and side scan sonar. Quality of dsata obtained during trials depends interalia on a proper location of antenna to reduce influence of pitch, roll and heave motions as well as ship noise.
-
Decisional DNA based intelligent knowledge model for flexible manufacturing system
PublicationModeling an effective mechanism for design and control strategies for the implementation of a flexible manufacturing system (FMS) has been a challenge. Consequently, to overcome this issue various techniques have applied in the past but most of these models are effective only for some specific situation or an element of FMS. In this study, the knowledge representation technique of Decisional DNA (DDNA) is applied to FMS to develop...
-
Model of control plane of ASON/GMPLS network
PublicationASON (Automatic Switched Optical Network) is a concept of optical network recommended in G.8080/Y.1304 by ITU-T. Control Plane of this network could be based on GMPLS (Generalized Multi-Protocol Label Switching) protocols. This solution, an ASON control plane built on GMPLS protocols is named ASON/GMPLS. In the paper, we decompose the control plane problem and show the main concepts of ASON network. We propose a hierarchical architecture...
-
Hybrid of Neural Networks and Hidden Markov Models as a modern approach to speech recognition systems
PublicationThe aim of this paper is to present a hybrid algorithm that combines the advantages ofartificial neural networks and hidden Markov models in speech recognition for control purpos-es. The scope of the paper includes review of currently used solutions, description and analysis of implementation of selected artificial neural network (NN) structures and hidden Markov mod-els (HMM). The main part of the paper consists of a description...
-
Selection of an artificial pre-training neural network for the classification of inland vessels based on their images
PublicationArtificial neural networks (ANN) are the most commonly used algorithms for image classification problems. An image classifier takes an image or video as input and classifies it into one of the possible categories that it was trained to identify. They are applied in various areas such as security, defense, healthcare, biology, forensics, communication, etc. There is no need to create one’s own ANN because there are several pre-trained...
-
Laboratory test rig for examining aggregate mining from seabed using the AIRLIFT method
PublicationThe use of the Airlift method for transporting the mined aggregate from the seabed to the deck of the mining ship is an alternative for presently used solutions, such as suction pumps or scoop transport for instance. Building the laboratory test rig was preceded by tests in natural conditions. The rig was designed in such a way as to model these conditions as close as possible, and to have potential for further development
-
Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublicationMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
-
Simulation model of IPMSM drive with rotor position estimator
PublicationThe paper presents a simulation model of electric drive consisting of: IPMSM motor, inverter and digital controller. The model was designed in Mathlab/Simulink. By modelling of the controller its discrete operation was taken into account in order to simulate precisely a specific sensorless control algorithm. A method for estimation of angular rotor position was proposed. Its mathematical algorithm was explained and errors were...
-
Safety integrity level verification for safety-related functions with security aspects
PublicationThe article is devoted some important issues of the functional safety analysis, in particular the safetyintegrity level (SIL) verification of safety functions to be implemented within the distributed controland protection systems with regard to cyber security aspects. The procedure for functional safety man-agement includes hazard identification, risk analysis and assessment, specification of overall safetyrequirements and definition...
-
Water-Lubricated Journal Bearings Marine Applications, Design, and Operational Problems and Solutions
PublicationWater-Lubricated Journal Bearings: Marine Applications, Design, and Operational Problems and Solutions provides cutting-edge design solutions, common problems and methods for avoiding them, and material selection considerations for the use of water-lubricated journal bearings in marine environments. These bearings have many advantages, including the absence of the potential for oil contamination. They are also sensitive, and their...
-
Towards a reliable method for extrapolation of propulsion performance for vessels with twin-crp-pod system
PublicationThe study presents power performance prediction of an Ultra Large Container Ship (ULCS) with hybrid twin-crp-pod propulsion system. Twin crp-pod propulsion system is a combination of three concepts: twin screw, contra-rotating propellers (crp) and conventional shaft propellers with pod propulsors behind. The presented study shows the current extrapolation method for crp propulsion systems and tries to point out its weaknesses....
-
Four-state stochastic model of changes in the reliability states of a motor vehicle
PublicationThe properties of semi-Markov processes have been generally characterized and the applicability of the theory of such processes to the determining of the reliability of motor cars and other road vehicles has been explained. A formal description of the process of changes in the motor vehicle technical states considered as reliability states and a model of this process in the form of a one-dimensional stochastic process have been...
-
Ships - inspiring objects in architecture
PublicationSea-going vessels have for centuries fascinated people, not only those who happen to work at sea, but first and foremost, those who have never set foot aboard a ship. The environment in which ships operate is reminiscent of freedom and countless adventures, but also of hard and interesting maritime working life. The famous words of Pompey: “Navigare necesseest, vivere non estnecesse” (sailing is necessary, living – is not necessary),...
-
Multicriteria Optimization Approach to Design and Operation of District Heating Supply System over its Life Cycle
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). In the paper a method for optimized selection of design and operating parameters of long distance Heat Transportation System (HTS) is proposed. The method allows for evaluation of feasibility and effectivity of heat transportation...
-
Improvement of ships seakeeping performance by application of the Full-scale CFD simulations – case study
PublicationThe ship’s fuel economy is increasingly important. The paper presents the effect of redesigning a case study ship for increasing seakeeping performance. Selected wave parameters reflects very difficult operational con-ditions existing on the North Sea and the Baltic Sea. The analyzed variants of a case study ship represent the latest developments of modern hull forms. The concepts similar to V-shaped bulbous bow, X-bow, X-aft,...
-
An application of multi-agent system for ship’s power systems design
PublicationDesign process of transport ship power system consists of structure (topology) and component elements selection. Compliance with the requirements for static components does not guarantee optimal dynamic characteristics of entire power system. Design steps are difficult to formalize and as a consequence to this reason expert and multi-agent systems are used for solving selected design issues. In the paper distributed multi-agent...
-
Towards improved energy efficiency of future smart ships by application of advanced CFD simulations – case study
PublicationThe international trade plays crucial role in today’s globally developed world’s economy. Many people are unaware of the unimaginable volume of cargo being transported every year by oceans and seas. For most of the time invisible from land the shipping industry preserves its strong position of the most cost-efficient and environmental friendly mean of transport. However during last years the shipping industry is under great pressure...
-
Steady-State Vibration Level Measurement of the Five-Phase Induction Machine during Third Harmonic Injection or Open-Phase Faults
PublicationMultiphase electric machines are increasingly used in various industries and for electromobility. Complex systems have been developed for the control and powering of multiphase machines, which require verification. The quality of control and the power supply of electric machines is usually evaluated by analyzing various electrical parameters. On the other hand, taking into account the fact that a motor is an electrical-mechanical...
-
Evaluation of the Greenness of Analytical Procedures
PublicationThis contributions introduces the need to develop the methods to evaluate analytical procedures in the light of green analytical chemistry. Green chemistry metrics are not applicable in analytical chemistry because they refer to the mass of product and no product with mass is generated during analytical determination. Analytical greenness evaluations are based on scoring - such as NEMI or Eco-scale or comparative analysis as it...
-
Impact of ITS services on the safety and efficiency of road traffic
PublicationThis paper describes the project entitled: “Impact of the use of Intelligent Transport Systems on the level of road safety” (agreement no. DZP/RID-I-41/7/NCBR/2016), implemented as part of the Road Innovations Development (RID) programme, funded by the National Centre for Research and Development and the General Directorate for National Roads and Motorways (GDDKiA). The project is run by a consortium comprising the Motor Transport...
-
Koncepcja i modelowanie silnika o wirującym tworniku oraz magneśnicy do zastosowania w napędzie miejskiego samochodu elektrycznego
PublicationW artykule zaprezentowano koncepcję, model oraz prototyp silnika z wirującym twornikiem oraz magneśnicą. Opisano historię powstania i zastosowania tego typu silników w motoryzacji. Przedstawiono nowoczesne rozwiązania konstrukcyjne i zastosowania we współczesnych samochodach elektrycznych i hybrydowych. Opracowano model silnika z wirującym twornikiem i magneśnicą oraz przedstawiono wybrane wyniki symulacji przeprowadzone w programie...
-
Evaluating the convenience and safety effects of bicycle lanes in Gdańsk
PublicationBicycle lanes are lanes marked on a road and dedicated for exclusive use for cyclists.. Because they combine bike and motor traffic they provide directness and flow. However, a shared use of streets could result in bicycle-car accidents. Following up on the good practice Western countries have in planning cycle infrastructure, Gdańsk has recently introduced bike lanes on a few streets. The aim of the research was to assess the...
-
Novel adaptive flux observer for wide speed range sensorless control of induction motor
PublicationA new adaptive flux observer of induction motor is presented in the paper. The Lyapunov theory is utilized for derivation of the adaptation law of rotor flux angular speed, which acts as unknown parameter in an augmented induction motor model. In the field weakening region, where stray fluxes are comparable with rotor flux magnitude, the air-gap flux stabilization is proposed. An air-gap flux multiscalar model is derived for stator...
-
PHYSICAL MODEL OF ENERGY-RELATED PROCESSES IN A ROTATING MECHANICAL SYSTEM FOR THE PURPOSES OF DIAGNOSIS OF TRANSMISSION SHAFTS
PublicationIn the present article, selected problems connected with identification of slowly changing energy-related processes accompanying high cyclic fatigue of construction materials of simple mechanical systems, with special consideration of transmission shafts, are mentioned for diagnostic purposes. The article also presents physical models of object and processes that in a simplified way reflect mechanical energy transmission from transmission...
-
Report no WOiO/II/67/2015 - Expertise about load capacity of twistlock foundation and sliding foundation
PublicationCustomer delivered to Laboratory 17 elements - twist lock foundations and sliding lock foundations (ship equipment for container lashing). Elements were selected from production series. Each element was loaded for braking load. After test visual inspection had been performed. The expertise contains: description of tested elements, test assumptions, test stand, results and conclusions
-
AN ALGORITHM FOR PORTAL HYPERTENSIVE GASTROPATHY RECOGNITION ON THE ENDOSCOPIC RECORDINGS
PublicationSymptoms recognition of portal hypertensive gastropathy (PHG) can be done by analysing endoscopic recordings, but manual analysis done by physician may take a long time. This increases probability of missing some symptoms and automated methods may be applied to prevent that. In this paper a novel hybrid algorithm for recognition of early stage of portal hypertensive gastropathy is proposed. First image preprocessing is described....
-
Electric shock hazard in circuits with variable-speed drives
PublicationThe conventional approach to electrical safety under fault condition in typical power systems considers earth fault currents of sinusoidal waveform and frequency of 50/60 Hz. However, in circuits with variable-speed drives, there is earth fault current flow with harmonics, and these harmonics influence the threshold of ventricular fibrillation. The paper presents earth fault current waveforms in circuits with variable-speed drives...
-
Modeling of traffic safety indictors on Polish national road network
PublicationAlthough decreased from 2001 to 2013, Poland’s road deaths improved at a slower rate than the rest of the EU, leaving Poland as one of the worst road safety performing countries in the EU. The national road network in Poland, despite the dynamic transformation and development, still does not conform to the EU safety standards. Similar situation exists in other EU countries, particularly those in Central and Eastern Europe. Safety...
-
COMPARATIVE ANALYSIS OF RESULTS OF APPLICATION OF MARKOV AND SEMI-MARKOV PROCESSES TO RELIABILITY MODELS OF MULTI-STATE TECHNICAL OBJECTS
PublicationDuring rational operation of technical objects and systems various operational decisions are made and decision-making process itself should be consisted in selecting that considered most favourable out of all possible to be taken. Choice of such decision is possible after taking into account many different information items but it never be completely correct without accounting for data and indices dealing with reliability. In...
-
The conception of energetic investigations of the multisymptom fatigue of the simple mechanical systems' constructional materials
PublicationThe article presents the basic assumptions of the research project aimed, as the main scientific purpose, an identification of the slow-changeable energy processes surrounding the high-cycle fatigue of constructional materials within the plain mechanical system, especially the marine one, for diagnostic purposes. There is foreseen an application of alternative diagnostic methods based on energetic observations of the multi-symptom,...
-
Decision support system for design of long distance heat transportation system
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). The paper proposes a Decision Support System (DSS) for optimized selection of design and operating parameters of a long distance Heat Transportation System (HTS). The method allows for evaluation of feasibility and effectiveness...
-
Application a laboratory stand for multi-symptoms tests for high cyclic fatigue of constructional material
PublicationThis paper describes a need of diagnostics present ship plants according to current technical state. In order to reach competent physical quantity describing fatigue of materials by congregated energy. This paper describes using some diagnostics methods (acoustic emission AE, vibration, thermovision, deformation) in order to definition fatigue state of construction material. The author tries to find correlation between measured...
-
Analysis of Signalized Intersections in the Context of Pedestrian Traffic
PublicationGdynia is a city in the Pomeranian Voivod e ship of Poland with a population of about 250,000. It faces a growing motorization rate th at needs to be addressed. Car ownership in Gdynia now exceed s 500 vehicles per 1000 residents. Travel by public transport is decreasing and the rate of walking and cycling remains low. It is necessary to reverse these negative trends by implementing solu tions based...
-
Development of a Response Assessment Tool for a Floating Dock System
PublicationDocking operations of ships require a response assessment to ensure structural and personnel safety. Environmental loads and improper ballast adjustments are the main threats to the docking operations. They can cause severe structural damages and stability loss to a floating dock system which includes a floating dock and a docked vessel, even if the velocities of the dock and the vessel are very low during the docking process....
-
APPLICATION OF QUANTITATIVE RISK ASSESSMENT TO SHIPS IN EMERGENCY CONDITIONS
PublicationThe paper is devoted to safety of ships in emergency conditions. The currently valid prescriptive method of safety assessment of ships in damage conditions is included in the SOLAS 2009 Part B-2 Ch.II-1 regulations. It is devoted to the design stage and difficult to apply in operation. A possible alternative described in this paper is a method based on assessment of performance of ships and risk assessment. Type of risk evaluation...