Filters
total: 1095
-
Catalog
- Publications 783 available results
- Journals 155 available results
- Conferences 1 available results
- Publishing Houses 2 available results
- People 14 available results
- Projects 2 available results
- e-Learning Courses 14 available results
- Events 1 available results
- Open Research Data 123 available results
displaying 1000 best results Help
Search results for: iranian nomads
-
Innovative Bidirectional Isolated High-Power Density On-Board Charge for Vehicle-to-Grid
PublicationThis paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching,...
-
Highly efficient maximum power point tracking control technique for PV system under dynamic operating conditions
PublicationThe application of small-scale electrical systems is widespread and the integration of Maximum Power Point Tracking (MPPT) control for Photovoltaic systems with battery applications further enhances the techno-economic feasibility of renewable systems. For this purpose, a novel MPPT control system using Dynamic Group based cooperation optimization (DGBCO) algorithm is utilized for PV systems. The population in the DGBCO is divided...
-
Green energy extraction for sustainable development: A novel MPPT technique for hybrid PV-TEG system
PublicationThe Photovoltaic (PV) module converts only a small portion of irradiance into electrical energy. Most of the solar energy is wasted as heat, resulting in a rise in PV cell temperature and a decrease in solar cell efficiency. One way to harvest this freely available solar thermal energy and improve PV cell efficiency is by integrating PV systems with thermoelectric generators (TEG). This cogeneration approach of the hybrid PV-TEG...
-
Seasonal contributions of nutrients from small urban and agricultural watersheds in northern Poland
PublicationDiffuse sources of pollution like agricultural or urban runoff are important factors in determining the quality of surface waters, although they are more difficult to monitor thanpointsources.Theobjectiveofourstudywastoverifyassumptionsthattheinflow from agricultural nutrient sources is higher than from urbanized ones. It has been done by comparing the nutrients and organic matter concentrations and loads for three small streams...
-
Effect of Overloaded Vehicles on Whole Life Cycle Cost of Flexible Pavements
PublicationThe phenomenon of vehicle overloading—illegal exceeding of maximum legal weight of vehicles, is a serious problem both in developing and developed countries around the world. Overloaded vehicles occur less frequently in comparison to properly loaded vehicles but due to their greater potential to cause damage they significantly contribute to distress of pavement structure. As studies show, the number of overloaded vehicles increases...
-
Knowledge management strategies in KIBS companies: A preliminary analysis
PublicationPurpose – The aim of this paper is to perform a preliminary analysis concerning the detection and examination of two possible opposite approaches to KM planning which will be referred to as deliberate and emergent KM strategies. The goal is to enhance our understanding of the variety of features KM strategies possess and, accordingly, to formulate categorisations that are in line with such characteristics. Design/methodology/approach...
-
The Main Buildings of Technical Universities in Lviv, Warsaw, Gdańsk and Wrocław. Neo-Renaissance „Architecture parlante”
PublicationThe article compares the buildings of historical campuses of four technical universities located in areas related to Polish culture. At the turn of the 19th and 20th centuries, several new technical universities were established in Central and Eastern Europe. In 1844, the Technical Academy was opened in Lviv. In 1899, the Russian who were occupying the east and central part of Poland established the Polytechnic Institute in Warsaw....
-
Mechanical Properties of Aluminium Bracket Strengthening
PublicationThe aim of the research is laboratory investigation of aluminium brackets employed to fasten lightweight curtain walls to building facilities. Tensile loads perpendicular to end plates (vertical) were applied here. The author focused on the solutions intended to increase the load-carrying capacity of aluminium brackets applying the plain washer form A (DIN 125; ISO 7089), plain washer with an outer diameter about 3d (DIN 9021;...
-
Vibration and buckling characteristics of nonlocal beam placed in a magnetic field embedded in Winkler–Pasternak elastic foundation using a new refined beam theory: an analytical approach
PublicationIn this article, a new refined beam theory, namely one variable first-order shear deformation theory, has been employed to study the vibration and buckling characteristics of nonlocal beam. The beam is exposed to an axial magnetic field and embedded in Winkler–Pasternak foundation. The von Kármán hypothesis along with Hamilton’s principle has been implemented to derive the governing equations for both the vibration and buckling...
-
System for monitoring road slippery based on CCTV cameras and convolutional neural networks
PublicationThe slipperiness of the surface is essential for road safety. The growing number of CCTV cameras opens the possibility of using them to automatically detect the slippery surface and inform road users about it. This paper presents a system of developed intelligent road signs, including a detector based on convolutional neural networks (CNNs) and the transferlearning method employed to the processing of images acquired with video...
-
Sensitivity analysis of critical forces of trusses with side bracing
PublicationThe present research is devoted to the study of out-of-plane buckling of trusses with elastic side bracing. Inthis paper, a sensitivity analysis of critical buckling loads of a truss due to bracing stiffness is carried out. A method based on the sensitivity analysis for the determination of the threshold bracing stiffness conditionfor full bracing of a truss is proposed. The influence lines of the unit change of the bracing stiffness...
-
Buckling of frame braced by linear elastic springs
PublicationIn the design codes and specifications, simplifed formulae or diagrams are given for determining the buckling lengths of frame columns based on the ruling criterion of considering frames as sway or non sway. Due to the fact that, the code formulae utilize onlylocal stifness distributions, these formulae may yield in certain cases rather erroneous results. In most code formulas a case of weakly braced frames is usually not considered.In...
-
Fully enzymatic mediatorless fuel cell with efficient naphthylated carbon nanotube-laccase composite cathodes
PublicationAn efficient, mediator-free enzymatic glucose/O2 biofuel cell with an oxygen intensive anode based on glucose dehydrogenase is presented. In the device,the power of the biofuel cell and electrode potentials of each of the enzymatic electrodes were monitored in parallel under the biofuel cell working conditions. The carbon nanotube composite biocathode demonstrates an almost constant electrode potential vs. saturated calomel electrode...
-
Systematics of intelligent transport systems services
PublicationRecent years have seen a more intensified deployment of Intelligent Transport Systems (ITS) in Polish cities. Work is also underway on the implementation of ITS on the national roads within the National Traffic Management System (KSZR). The research project RID-4D (part of Road Innovations), is designed to fill the gap, which is the lack of systematics of ITS services in Poland. The paper presents a proposal of ITS services systematics,...
-
CFD Simulations and Tests of a Prototype Flow Control Valve
PublicationIn this paper a prototype of a flow control valve is described and numerically simulated. The flow control valve is used in hydraulic systems to maintain constant fluid flow despite changing loads of a receiver. The standard construction of this type of valves is modified mainly by eliminating the spring. The prototype consists the hydrostatically unloaded throttle valve and pressure ratio valve substituting pressure difference...
-
Heuristic scheduling algorithms for uniform load of computer system
PublicationW pracy zaprezentowano opracowany heurystyczny algorytm szeregowania zadań UNILO (ang. UNIform LOad - jednakowe obciążenie), umożliwiający redukcję całkowitego zapotrzebowania na moc obliczeniową systemu komputerowego bez pogarszania jego wydajności. Algorytm ten realizuje takie przydzielenie zadań obliczeniowych do poszczególnych jednostek (procesorów), aby zapewnić ich jednakowe obciążenie. Opracowany algorytm został zweryfikowany...
-
Vibration monitoring of structures in the light of the Polish and international requirements
PublicationThe paper concerns the wide range of strategies used to protect structures against man-made dynamic excitation. The most popular approaches applied worldwide are compared, and the main differences and similarities are summarized. The literature studies are supported by the results of the measurements performed on different types of real structures, which are sensitive and insensitive to the dynamic load. To make the conclusions...
-
Identifying the Effects of Selected Road and Roadside Parameters on Road Safety Using Geodetic Techniques
PublicationThe paper will present techniques that can be used to obtain data on road alignment and profile including the roadside. In-the-field and simulation studies have helped to develop mathematical models that integrate vehicle position data. The experiments were conducted in a virtual environment using the software ArcGIS that reflects the actual roadside conditions. The site tests were made using a purpose-built device which integrates...
-
The influence of accumulation area and the length of pedestrian route on functioning of roundabouts with traffic signals
Publicationtraffic volumes. This kind of intersection is commonly used in the centres of Polish cities on multilane roads and fairly common in the case of tram lines running through a central island. The increase of traffic flow volumes on left turn and U-turn has made this type of roundabout difficult to operate. Small storage areas around central islands are critical places that significantly influence the capacity of this kind of intersection....
-
The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
PublicationThis paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic,...
-
Road surface roughness estimation employing integrated position and acceleration sensor
PublicationAssessment of a surface quality being an essential task for the authorities supervising the roads provides the subject of the paper. Information about riding quality of a pavement, important for drivers, both in terms of their comfort and safety is collected during experiments employing mobile sensors. The paper describes the use of a miniature position and acceleration sensor for evaluation of the roughness of the road surface....
-
Polish Experience of Implementing Vision Zero
PublicationPurpose of Review The aim of this study is to present an outline and the principles of Poland’s road safety strategic programming as it has developed over the last 25 years since the first Integrated Road Safety System with a strong focus on Sweden’s “Vision Zero”. Recent Findings Countries that have successfully improved road safety have done so by following strategies centred around the idea that people are not infallible and...
-
Chemical and Mechanical Properties of 70-Year-Old Concrete
PublicationThe aim of this research is to determine the durability and strength of concrete continuous footing based on the chosen mechanical, physical, and chemical properties of the concrete. The presented investigations constitute some opinions from experts on the bearing capacity of concrete continuous footing and the possibilities of carrying additional loads and extended working life. The cylindrical specimens were taken from continuous...
-
Linking habitat composition, local population densities and traffic characteristics to spatial patterns of ungulate‐train collisions
Publication -
Villages and their old farmsteads are hot spots of bird diversity in agricultural landscapes
Publication -
Sympathetic neural responses to coronary occlusion during balloon angioplasty
Publication -
Why are trees still such a major hazard to drivers in Poland?
PublicationRoadside trees are one of Poland's most serious road safety issues. Since 2009 more than 2800 people have been killed as a result of tree collisions; this represents about 15% of all of Poland's accident fatalities between 2009 and 2013. In some of the country's regions striking a tree caused more than 30% of all road accident fatalities. With no proper regulations, guidelines or examples of good practice, roadside environments...
-
Searching for innovation knowledge: insight into KIBS companies
PublicationPurpose – The paper analyzes the patterns of research of “innovation knowledge” (i.e. knowledge that can result in introducing innovations in the company that can be observed in KIBS (Knowledge-Intensive Business Services) companies. Particularly, it identifies and classifies the possible approaches adopted by companies on the basis of two dimensions: the intensity/proactivity of search efforts, and the source primarily used. Design/methodology/approach...
-
Designing of Parking Spaces on Parking Taking into Account the Parameters of Design Vehicles
PublicationNowadays, in all cities, there is an acute problem of a lack of parking spaces. The number of vehicles is constantly increasing not only in big cities and megacities, but also in small towns of the country, and there are not enough parking places—the pace of solving the problem is several times slower than the growth rate of transport among citizens. The paper is dedicated to the determination of an optimal size of a parking place...
-
The Influence of External Additional Loading on the Muscle Activity and Ground Reaction Forces during Gait
PublicationAsymmetrical external loading acting on the usculoskeletal system is generally considered unhealthy. Despite this knowledge, carrying loads in an asymmetrical manner like carrying on one shoulder, with one hand, or on the strap across the torso is a common practice. This study is aimed at presenting the effects of the mentioned load carrying methods on muscle activity assessed by using thermal field and ground reaction forces....
-
Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
PublicationIn the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness...
-
Influence of sludge treatment processes on heavy metal speciation
PublicationSludge composition is depending on sewage quality and also affected by processing methods such as thickening, stabilization and dewatering. During those processes some of sludge's undesirable properties might be reduced or enhanced.The objective of the study is the assessment of the influence of sludge processing on selected heavy metals partitioning between phases (aqueous and particle) and sludge. Sludge from the WWTP in Gdansk...
-
Development and tuning of irregular divide-and-conquer applications in DAMPVM/DAC
PublicationThis work presents implementations and tuning experiences with parallel irregular applications developed using the object oriented framework DAM-PVM/DAC. It is implemented on top of DAMPVM and provides automatic partitioning of irregular divide-and-conquer (DAC) applications at runtime and dynamic mapping to processors taking into account their speeds and even loads by other user processes. New implementations of parallel applications...
-
RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublicationThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
-
Response of a steel tank during earthquakes and mining tremors - experimental investigation
PublicationCylindrical steel tanks are very popular shell structures used to store the products of chemical and petroleum industries. Any failure might have disastrous consequences, therefore their safety and reliability is essential. Earthquakes are the most dangerous and also the most unpredictable dynamic loads acting on such structures. On the other hand, mining tremors are usually considered to be less severe due to lower acceleration...
-
Probabilistic sensitivity of limit states of structures. The Monte Carlo simulation
PublicationDesign sensitivity deals with the variation of structural response, implicitly dependent on the design variables of the problem. An attempt is made to implement probabilistic notation in engineering sensitivity analysis. The procedure to implement the sensitivity of a structural limit state to a given basic variable is described in the paper - its main idea, depicted by a flowchart and numerical examples of engineering analysis....
-
A multi-agent method for periodicity detection in distributed events
PublicationMulti-agent systems working in constantly changing environments may be challenged by instantaneous unavailability of their autonomous agents caused e.g. by limited computing resources. A new method of self-organization of distributed service components is proposed, suitable for multi-agent systems. This method relies on particular agents carrying out separate analyzes of their individual processing loads or other specific events....
-
Experimental study on static and dynamic properties of polymer mass
PublicationA new method of repairing damaged structures by filling the cracks with a specially prepared polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure. The aim of the...
-
The impact of material degradation on the resistance and reliability of truss structures
PublicationThe paper analyses limit load-carrying capacity and buckling load of truss towers used to support high voltage power lines. The analysed typical structure was subjected to characteristic loads and their combinations. The results were applied to assess structural resistance with regard to steel corrosion in the long-term operation. The extent of structural deterioration was assessed due to Young's modulus decrement in the course...
-
Development of tools for road infrastructure safety management for the provinces (voivodeships) in Poland
PublicationThe development of modern tools for road infrastructure safety management will help to reduce the number of fatalities and serious injuries as one of the main objectives adopted in 2013 in the National Road Safety Programme 2014-2020 and the new Road Safety Programme 2011-2020 in the EU. Risk Management in Highway Engineering can be applied in developing tools essential in the process of safety management. Risk Management in Highway...
-
Rigid finite elements and multibody modeling in analyses of a robot shaped elastic/plastic deformations of a beam
PublicationDynamics analysis of a system composed of a parallel manipulator and of an elastic beam is presented in the paper. Classic 3RRR parallel manipulator is considered and used to deform the beam. Elasto-plastic deformations are investigated. Rigid-finite-elements technique is employed to deal with dynamics of the beam. A multibody structure is associated with the introduced hybrid system in order to model its dynamics. Idea of the...
-
Buckling of simplified models of silo with corrugated walls and vertical stiffeners
PublicationThe paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...
-
Pesticide Analysis of Bee and Bee Product Samples
PublicationBee products possess therapeutic properties and are the source of many essential trace elements,which is why they are regarded as valuable food products. Honey bees may bring to thehive numerous contaminants deposited on the plants they visit, including pesticide withoutxenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead tomass mortality among bees, and the chemicals find their way into...
-
Pesticide analysis of bee and bee product samples
PublicationBee products possess therapeutic properties and are the source of many essential trace elements,which is why they are regarded as valuable food products. Honey bees may bring to thehive numerous contaminants deposited on the plants they visit, including pesticide withoutxenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead tomass mortality among bees, and the chemicals find their way into...
-
Vehicular Communication Environments
PublicationCommunication to and between road vehicles (cars, truck, buses, trains, etc.) are of growing interest. This is partly due to the attractive services that cooperative intelligent transport systems (C-ITSs) provides, mainly in the areas of traffic safety and traffic efficiency. An enabler for C-ITS is wireless vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, collectively referred to as vehicle-to-X (V2X)...
-
Sensitivity of binomial N‐mixture models to overdispersion: The importance of assessing model fit
Publication -
An independent relationship between muscle sympathetic nerve activity and pulse wave velocity in normal humans
Publication -
Możliwości zastosowań, potencjalne źródła oraz ewolucja technologiczna sposobu otrzymywania trehalozy ze szczególnym uwzględnieniem enzymu syntazy trehalozy [EC 5.4.99.16]
PublicationJedna z wiodących gałęzi współczesnej biotechnologii opiera się na produkcji białek – przede wszystkim enzymów. Są one powszechnie wykorzystywane: od przemysłu chemicznego poprzez przemysł spożywczy aż po medycynę i życie codzienne (czy ktoś wyobraża sobie w dzisiejszych czasach proszek do prania „bez enzymu”). Przed rozwojem nowoczesnych metod biologii molekularnej i inżynierii genetycznej pozyskiwano interesujące substancje z...
-
The Influence of Cement Type on Early Properties of Cold In-Place Recycled Mixtures
PublicationCold in-place recycling is a commonly used maintenance treatment in rehabilitation of low and medium volume roads in Poland. Typically, two types of binding agents are used—cement and bituminous emulsion (or foamed bitumen).Due to the harsh Polish climate with many freeze/thaw cycles and frequent occurrence of saturated conditions, the used amounts of cement are higher than those commonly used in warmer parts of Europe. While there...
-
On topology optimization of large deformation contact-aided shape morphing compliant mechanisms
PublicationA topology optimization approach for designing large deformation contact-aided shape morphing compliant mechanisms is presented. Such mechanisms can be used in varying operating conditions. Design domains are described by regular hexagonal elements. Negative circular masks are employed to perform dual task, i.e., to decide material states of each element and also, to generate rigid contact surfaces. Each mask is characterized by...