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SENSITIVITY ANALYSIS IN THE REHABILITATION OF HISTORIC TIMBER STRUCTURES ON THE EXAMPLES OF GREEK CATHOLIC CHURCHES IN POLISH SUBCARPATHIA
PublicationThis work concerns structural and sensitivity analysis of carpentry joints used in historic wooden buildings in south-eastern Poland and western Ukraine. These are primarily sacred buildings and the types of joints characteristic for this region are saddle notch and dovetail joints. Thus, in the study the authors focus on these types of corner log joints. Numerical models of the joints are defined and finite element simulations...
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Miniaturized solid phase extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 2
PublicationDetermination of pollutants present in environmental samples at a low concentration level very often requires the analytical protocol that includes analytes isolation and/or enrichment prior to the final quantification. Miniaturized SPE offers an interesting alternative to LLE. Nowadays, many types of sorbents are available and can be used as selective materials for extraction of varied analytes in different kinds of samples. The...
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Topological behavior mimicking ethylene–hexene copolymers using branched lactones and macrolactones
PublicationPolyolefins are of paramount importance in the world of polymers due to their technological and economic potential.1 However, their nonpolar character significantly restricts the compatibility and adhesion properties, which consequently limits their versatility. Moreover, an intensified demand for materials from renewable resources can also become a problematic venture for the current polyolefin industry.2 Although Braskem and...
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Plastic Debris in the Stomach of the Invasive Signal Crayfish Pacifastacus leniusculus from a Baltic Coastal River
PublicationPollution by plastic debris, widely recognized as a growing global problem [1-3] is caused by the production of synthetic polymers. Over recent years, the production of plastics has increased, while in Europe, fossil-based plastics production has decreased, and recycled plastics production has increased [4]. There are different types of plastics. Some types of plastic ingredients, applied in a wide variety of cosmetics and personal...
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The risk of corporate bankruptcy - the conceptual model
PublicationThis article concerns the assessment of different types of risks influencing the corporate bankruptcy risk. The author has developed conceptual model that explains the causes and the trajectories of the collapse of enterprises. In the analyses such factors as demographic, financial, market, political and operational factors influencing the risk of failure were taken into account.
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Bezpieczeństwo funkcjonalne i ochrona informacji w obiektach i systemach infrastruktury krytycznej - analiza i ocena
PublicationW niniejszym rozdziale monografii przedstawiono bardzo aktualną problematykę związaną z analizą bezpieczeństwa funkcjonalnego rozproszonych systemów sterowania i automatyki zabezpieczeniowej w obiektach infrastruktury krytycznej, wykorzystujących przemysłową sieć komputerową, z uwzględnieniem zagadnień ochrony informacji. W obiektach tego typu systemy sterowania i automatyki zabezpieczeniowej są projektowane jako systemy rozproszone,...
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Impact of power electronic Var compensators installed in certain grid points on the voltage failure
PublicationThe article presents the test results of the various types of static compensators FACTS models in the power system. The basic case, which was analyzed, it was behavior of compensators which are installed in select points of the system during voltage failure. The article presents selected results of studies conducted as part of a work [2].
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Cooperative Data Transmission in Wireless Vehicular Networks
PublicationThe paper presents issues related to the cooperative transmission in wireless vehicular networks. Cooperative transmission involves the use of mobile terminals as relay stations to improve the transmission quality, improve network performance and reduce energy consumption. The paper presents the methods used to implement cooperative transmission and the types of cooperative networks.
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Complementary use of GCxGC–TOF–MS and statistics for differentiation of variety in biosolid samples
PublicationFormation of biosolid cakes, which are one of the main wastes generated in wastewater treatment plants, is connected with emission of many hazardous chemical compounds, including odoriferous ones. To optimize particular processes of biosolid cake processing, it is necessary to assess chemical composition of the gas mixtures containing the compounds released from the cakes. The paper proposes application of two-dimensional gas chromatography...
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Historical carpentry corner log joints—Numerical analysis within stochastic framework
PublicationThe paper presents the results of numerical analysis performed on historical, traditional carpentry corner logjoints of two basic topologies: the short-corner dovetail connection and the saddle notch connection. These types of carpentry joints are commonly used in currently preserved objects of wooden architecture. All connections have been modelled in pinewood, which has been defined in the Finite Element software MSC.Marc/Mentat...
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Tyre rolling resistance and its influence on fuel consumption
PublicationRolling resistance of tyres is one of the major resistive forces acting on any wheeled vehicle. Unfortunately, it is also one of the forces very difficult to measure. It is estimated that in certain traffic conditions (like for example constant speed driving with slow or moderate speed) so called Rolling Resistance Impact Factor may be as high as 0.3. This means that reduction of rolling resistance by 50% would lead to 15% of energy...
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Experimental research on technical fabric of the Forest Opera Roof in Sopot
PublicationThe experimental analysis of the technical fabric Valmex is presented. The study involves uniaxial tensile, cyclic, rheological and biaxial tests. Some of the main differencies between two types of the analysed material have been identified. Mechanical properties of the textile have been modeled by the viscoelastic standard model with quite good effect.
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Modelling of blood flow: from macro to microscales
PublicationThe aim of this paper it to review various scale approaches to blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic description. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented.
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Water and chemical properties of hydrometeors over central european mountains
PublicationAtmospheric pollutants are transferred to the groundby the contribution of various types of hydrometeors. Because ofthe different techniques of measurement, comparative analysesbetween them are often neglected. Hence, the main goal is tocompare water volume and chemistry of different types ofhydrometeors and their role in both: water balance and pollutantsdeposition. The results of water input and atmospheric depositschemistry...
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Research and applications of active bearings: A state-of-the-art review
PublicationControllable/active bearings are mainly associated with active magnetic bearings (AMBs), whereas active bearing control is also found in many types of bearings, e.g. fluid, gas and hybrid bearings. The article presents a review of the literature describing the structure and results of studies of active bearings. Active control brings a number of benefits resulting in the fact that their use as a support for rotors becomes increasingly...
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Polysaccharides in fabrication of membranes: A review
PublicationSustainability concerns have motivated and directed a great deal of interest over the past decade towards the development of green technologies. Polysaccharides are green polymers, which experienced growing demand to substitute chemically synthetic polymers. Different types of polysaccharides i.e. cellulose-, starch-, chitin- alginate-, and chitosan-based carbohydrate polymers have been applied in the fabrication of separation...
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Application of Structural Control Systems for the Cables of Cable-Stayed Bridges: State-of-the-Art and State-of-the-Practice
PublicationStay cables are one of the key elements of cable-stayed bridges and are characterized by lightweight, low inherent damping, and high flexibility. They are continuously subjected to small-to large-amplitude vibrations due to various types of dynamic loads that may, in the long term, cause fatigue and fracture problems for the cable system, and may eventually compromise the safety of cable-stayed bridges. Thus, several countermeasures...
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Critical review of electronic nose and tongue instruments prospects in pharmaceutical analysis
PublicationElectronic nose (enose, EN) and electronic tongue (etongue, ET) have been designed to simulate human senses of smell and taste in the best possible way. The signals acquired from a sensor array, combined with suitable data analysis system, are the basis for holistic analysis of samples. The efficiency of these instruments, regarding classification, discrimination, detection, monitoring and analytics of samples in different types...
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Nonlinear generation of non-acoustic modes by low-frequency sound in a vibrationally relaxing gas
PublicationTwo dynamic equations referring to a weakly nonlinear and weakly dispersive flow of a gas in which molecular vibrational relaxation takes place. are derived. The first one governs an excess temperature associated with the thermal mode, and the second one describes variations in vibrational energy. Both quantities refer to non-wave types of gas motion. These variations are caused by the nonlinear transfer of acoustic energy into...
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Chapter 8 – Active Sampling of Air
PublicationThis chapter reviews the literature information on analytical techniques and laboratory equipment used for active sampling of air (atmospheric and indoor) in regular monitoring research. It describes popular analytical devices applied for sample collection using various types of polymeric bags, e.g. Tedlar bags, Teflon or Nafion bags, and/or stainless steel vacuum containers. It reviews literature data about the application of...
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Hold-Up Problems in International Gas Trade: A Case Study
PublicationThe infrastructure required for international natural gas trade is considerable, which often leads to hold-up problems and supply disruptions. This study discusses disruptions of gas supply from Algeria, Indonesia, Russia, and Turkmenistan since the early 1980s. The novelty of this study is its focus on the issues related to transit countries, which are rarely considered in the literature. The results of the study classify supply...
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Advanced Lithium-Ion Battery Model for Power System Performance Analysis
PublicationThe paper describes a novel approach in battery storage system modelling. Different types of lithium-ion batteries exhibit differences in performance due to the battery anode and cathode materials being the determining factors in the storage system performance. Because of this, the influence of model parameters on the model accuracy can be different for different battery types. These models are used in battery management system...
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Further development of the poroelastic road surface within the new Polish project SEPOR
PublicationRoad surfaces have a direct impact on noise generated by rolling tyres, the main and dominant source of noise of moving vehicles. Road surface texture, porosity and stiffness/elasticity govern the pavement contribution to tyre/road noise the most. An experimental PoroElastic Road Surface (PERS) is a wearing course with a high content of interconnected voids (pores) and with an elastic behavior due to the use of small particles...
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Deep Learning-Based, Multiclass Approach to Cancer Classification on Liquid Biopsy Data
PublicationThe field of cancer diagnostics has been revolutionized by liquid biopsies, which offer a bridge between laboratory research and clinical settings. These tests are less invasive than traditional biopsies and more convenient than routine imaging methods. Liquid biopsies allow studying of tumor-derived markers in bodily fluids, enabling the development of more precise cancer diagnostic tests for screening, disease monitoring, and...
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Silence/noise detection for speech and music signals
PublicationThis paper introduces a novel off-line algorithm for silence/noise detection in noisy signals. The main concept of the proposed algorithm is to provide noise patterns for further signals processing i.e. noise reduction for speech enhancement. The algorithm is based on frequency domain characteristics of signals. The examples of different types of noisy signals are presented.
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A New Canon of the Modernist Villa of the 1930s - a Villa with a Semicircular Veranda. The Post-War Continuation of the Idea
PublicationThe articcle presents a new type of villa, which started to be popular in Gdynia in the 1930s. It was a villa with a semicircular veranda. Villas of that type were continously built also after the II World War
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Application of Intelligent Conversational Agents in E-learing Environments
PublicationThe paper concerns intelligent tutoring systems and concentrates on apliaction of virtual mentors in distance learning environments. Different educational agent types are described. The prototype of an agent developed at Gdansk University of Technology is also presented, as well as its internal representation and construction. Benefits of virtual mentors applied in distance learning are also pointed out.
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Blast Charge Technique as a Method of Soil Improving to Locate the New Supporting Runways
PublicationA quick and effective method of reinforcing the ground base designed for the construction of engineering structures used for performing various types of air operations was presented. It allows to use wastelands, wetlands, swamps, etc. for these purposes, thus creating a dispersed network of landing sites, increasing the access of large social groups to air transport and increasing their mobility.
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Reduction of road traffic noise by source measures — present and future strategies
PublicationThe current trend worldwide is less focused on reducing road traffic noise. This is in strong contrast to the severe impact of traffic noise to the general health and quality of life. A more holistic and combined strategy is needed. Current international rules and regulations regarding vehicles and tyres are not sufficient to reduce traffic noise levels in an effective way. Calculations show that these regulations will only yield...
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Analysis of noise properties of the optocoupler device
PublicationIn the paper the localization of a source of Random Telegraph Signal noise (RTS noise) in optocoupler devices type CNY 17 were defined. The equivalent noise circuit in low frequency noise for these type optocouplers was proposed.
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Kompozytowy most dla pieszych. Badania doświadczalne i przygotowanie do projektowania
PublicationDysertacja powstała w ramach grantu badawczego NCBiR, pt. „Opracowanie kompozytowych przęseł mostów dla pieszych do zastosowania nad drogami GP”, nr PBS1/B2/6/2013. Głównym celem pracy było wsparcie procesu projektowania kompozytowego mostu pieszo-rowerowego. Zakres pracy obejmuje badania doświadczalne elementów kompozytowych GFRP, walidację modeli obliczeniowych oraz wykorzystanie aparatu analizy wrażliwości do procesu projektowego....
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Gas chromatography-olfactometry (GC-O), electronic noses (e-noses) and electronic tongues (e-tongues) for in vivo food flavour measurement
PublicationThe capter revies two types of artificial olfaction instrumentation, i.e. gas-chromatography-olfactometry (GC-O) and chemical sensor technologies (electronic nose and tongue), combined with multivariate data processing methods as promising approaches for rapid analysis of food. The chapter also includes examples of specific applications for the detection of food flavour and volatile components.
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The Transmission Protocol of Sensor Ad Hoc Networks
PublicationThis paper presents a secure protocol for a radio Ad Hoc sensor network. This network uses the TDMA multiple access method. The transmission rate on the radio channel is 57.6 kbps. The paper presents the construction of frames, types of packets and procedures for the authentication, assignment of time slots available to the node, releasing assigned slots and slots assignment conflict detection.
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EVENTS VISUALIZATION POST IN A DISTRIBUTED TELEINFORMATION SYSTEM FOR THE BORDER GUARD
PublicationEvents Visualization Post is a part of the STRADAR project, which is dedicated to streaming real-time data in distributed dispatcher and teleinformation systems of the Border Guard. Events Visualization Post is a software designed for simultaneous visualization of data of different types. In the paper, the structure of the software is presented, the process of generation of tasks is described, and the visualization of audio, files,...
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On the use of a charge balancing method for low energy measurements
PublicationThe paper presents the method for the estimation of the energy consumption of the low-power microcontroller-based devices. Due to high dynamics of the changes of the supply current of the tested devices during the operational cycle, the consumed energy estimation is not easy. In order to avoid disadvantages of known methods, the charge balancing method was employed similarly like in some types of A/D converters.
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Issues of Estimating the Maximum Distributed Generation at High Wind Power Participation
PublicationThis paper presents the methods of estimating the maximum power that can be connected to the power system in distributed generation sources. Wind turbine generator systems (WTGS) were selected as the subject for analysis. Nonetheless, the considerations presented in this paper are only general and also apply to other types of power sources, including the sources that are not considered part of distributed generation.
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The reactions of dialkyl phosphites and phosphine oxides with iodosylbenzene
PublicationThe reaction of iodosylbenzene with >P(O)H type of acids (dialkyl phosphites, secondary phosphine oxides) was studied. The acids of >P(O)H type add to iodosylbenzene to yield intermediate 6 which in the aprotic solvents yields oxidation products, it means >P(O)OH acids and/or anhydride of >P(O)OP(O)< type. On the other hand if the reaction is performed in alcohol as a solvent in the presence of sodium alcoholate >P(O)OR ester is...
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MOODLE MOOCS - PRZYPADKI UŻYCIA W PROJEKCIE SP4CE (PARTNERSTWO STRATEGICZNE NA RZECZ KREATYWNOŚCI I PRZEDSIĘBIORCZOŚCI)
PublicationProjekt SP4CE (Partnerstwo strategiczne na rzecz kreatywności i przedsiębiorczości) jest odpowiedzią na potrzeby zidentyfikowane w komunikacie z Brugii w sprawie ściślejszej europejskiej współpracy w dziedzinie kształcenia i szkolenia zawodowego w latach 2011 - 2020. Do realizacji portalu SP4CE wykorzystano oprogramowanie WordPress i Moodle. WordPress wykorzystano m.in. do udostępnienia materiałów informacyjnych oraz szkoleniowych...
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Razem czy osobno - zespoły a działania przedsiębiorcze
PublicationPrzedsiębiorczość rozumiana jako atrybut jednostki, charakteryzowana jest ponad 40 pojęciami. Wiadomo jest jednak, że zakres i różnorodność kompetencji pojedynczej osoby jest zazwyczaj mniejszy niż zespołu. Jednostka może posiadać wybitną wiedzę, niezwykły poziom umiejętności i ogromne doświadczenie, ale ich zakres może zostać rozszerzony o właściwie dobrane kompetencje innej jednostki. Z drugiej strony zarówno działania zespołowe...
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Przedsiębiorcy 55+, czy wiek ma znaczenie?
PublicationZnaczenie przedsiębiorczości 55+ w ostatnim okresie rośnie, między innymi w związku ze zmianami demograficznymi i starzeniem się społeczeństwa w większości krajów europejskich. Nie bez znaczenia jest także fakt, że starsi ludzie zaczynają wierzyć, że mogą uczestniczyć w rynku pracy, zarówno po stronie zatrudnianych jak i zatrudniających. Stąd też liczba nowych firm, tworzonych przez osoby starsze wzrasta, a starsi właściciele firm...
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Thermoplastic Elastomers Filled With GTR
PublicationIn recent years, searching for new and cost-effective methods of recycling waste tires has been a subject of research in many laboratories worldwide. This is due to regulations in the law and environmental factors, which have both stimulated industry to re-use high quality rubber found in ground tire rubber (GTR). One of the most promising solutions in this area seems to be thermoplastic elastomers (TPEs) filled with GTR, which...
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Studying road restraint systems to develop new guidelines
PublicationThe paper will present a proposed approach to such work along with preliminary results of numerical studies for selected problems using road safety devices such as safety barriers on horizontal curves, the effect of kerbs on bridges or the location of obstacles within the barrier’s working width. The paper will discuss assumptions to a methodology of numerical models, calculations and automated processing of data to help with assessing...
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Estimation of Vehicle Energy Consumption at Intersections Using Microscopic Traffic Models
PublicationThis paper addresses issues related to modeling energy consumption and emissions using microscopic traffic simulations. This paper develops a method in which a traffic model is used to calculate the energy needed to travel through selected types of intersections. This paper focuses on energy consumption and derived values of calculated energy, which can be, for example, carbon dioxide emissions. The authors present a review of...
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A model of fuel combustion process in the marine reciprocating engine work space taking into account load and wear of crankshaft-piston assembly and the theory of semi-Markov processes
PublicationThe ar ticle analyses the operation of reciprocal internal combu stion engines, with mar ine engines u sed a s an example. The analysis takes into account types of energy conversion in the work spaces (cylinders) of these engines, loads of their crankshaft-piston assemblies, and types of fuel combustion which can take place in these spaces during engine operation. It is highlighted that the analysed time-dependent loads of marine...
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Application of 3D- printed hydrogels in wound healing and regenerative medicine
PublicationHydrogels are three-dimensional polymer networks with hydrophilic properties. The modifiable properties of hydrogels and the structure resembling living tissue allow their versatile application. Therefore, increasing attention is focused on the use of hydrogels as bioinks for three-dimensional (3D) printing in tissue engineering. Bioprinting involves the fabrication of complex structures from several types of materials, cells,...
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Evaluation of Mechanical Properties of Two-Stage Concrete and Conventional Concrete Using Nondestructive Tests
PublicationDifferent types of concrete mixtures are used as building materials. The manufacturing process of two-stage concrete (TSC) differs from that of conventional concrete. This study investigated conventional mechanical properties derive empirical relations for estimation of the mechanical parameters of TSC and conventional concrete mixtures. TSC was used to prepare 216 specimens and conventional concrete was used to prepare 108 specimens...
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Measurements of Thermal Conductivity of LWC Cement Composites Using Simplified Laboratory Scale Method
PublicationThe implementation of low-energy construction includes aspects related to technological and material research regarding thermal insulation. New solutions are sought, firstly, to reduce heat losses and, secondly, to improve the environment conditions in isolated rooms. The effective heat resistance of insulating materials is inversely proportional to temperature and humidity. Cement composites filled with lightweight artificial...
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Flow maldistribution and its mitigation in mini heat exchangers
PublicationIn the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel 1 mm x 1 mm rectangular minichannels and 1 mm depth minigap section with rectangular, trapezoidal, triangular or concave mani-folds in Z-type flow configuration (16 different cases). The working medium was ethanol and the mass flow rate was 5×10-4 kg/s. Both sections was heated from the bottom side. Heat...
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Effect of Polymerization Statistics on the Electronic Properties of Copolymers for Organic Photovoltaics
PublicationStatistical block copolymers, composed of donor (D) and acceptor (A) blocks, are a novel type of material for organic photovoltaics (OPVs) devices. In particular a new series of polymers based on PBTZT-stat-BDTT-8, recently developed by Merck, offers high solubility in different solvents, and a high power conversion efficiency (PCE) in different device architectures. Although it is known that the electronic properties of these...
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Strength analysis of the support structure of the offshore wind turbine
PublicationThe global power demand from renewable sources is growing. One of a very favorable solution which meets severe environmental protection requirements are the offshore wind turbines. The offshore wind energy sector has experienced very fast development over last decade. Offshore wind farms, in comparison with onshore applications, can provide increased efficiency with reduced noise, visual, transportation and installation con-flicts....