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Modelling Wetland Growing Season Rainfall Interception Losses Based on Maximum Canopy Storage Measurements
PublicationThis study estimates rainfall interception losses from natural wetland ecosystems based on maximum canopy storage measurements. Rainfall interception losses play an important role in water balance, which is crucial in wetlands, and has not yet been thoroughly studied in relation to this type of ecosystem. Maximum canopy storage was measured using the weight method. Based on these measurements, daily values of interception losses...
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The influence of IT-competency dimensions on job satisfaction, knowledge sharing and performance across industries
PublicationPurpose – Technology makes knowledge management easier. Knowledge sharing is essential for organizational development. Job satisfaction fosters knowledge sharing. Hence, this study aims to develop an understanding of the mutual relationship between knowledge sharing and job satisfaction when both are predicted by information technology (IT)-competency dimensions such as IT-operations, IT-knowledge and IT-infrastructure in the context...
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Automatic labeling of traffic sound recordings using autoencoder-derived features
PublicationAn approach to detection of events occurring in road traffic using autoencoders is presented. Extensions of existing algorithms of acoustic road events detection employing Mel Frequency Cepstral Coefficients combined with classifiers based on k nearest neighbors, Support Vector Machines, and random forests are used. In our research, the acoustic signal gathered from the microphone placed near the road is split into frames and converted...
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Soft Sensor Application in Identification of the Activated Sludge Bulking Considering the Technological and Economical Aspects of Smart Systems Functioning
PublicationThe paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including:...
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Tacit knowledge influence on intellectual capital and innovativeness in the healthcare sector: A cross-country study of Poland and the US
PublicationThis study provides empirical proof that whole organizational innovativeness is rooted in tacit knowledge due to its potency of human capital creation and, that a learning culture composed of a learning climate and mistakes acceptance component fosters human capital development. The main practical implication is that if the IC components are externally rather than internally determined in the particular organization embedded in...
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The Indonesian economy in 2005: An analysis using the input-output approach
PublicationThis study aims to analyze the economic conditions of Indonesia in 2005. This study employs Input-Output (IO) analysis as an analysis instrument. The data of this study is the Indonesian IO table for 2005. Thus, the Indonesian economy is represented by Indonesian industrial sectors mentioned in the data. There are nine industries used in the present study, namely (1) agriculture, livestock, forestry, and fishery, (2) mining and...
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Monitoring Trends of Land Use and Land Cover Changes in Rajang River Basin
PublicationIn this study, the spatiotemporal changes in land use and land cover (LULC) were evaluated from 1992 to 2015 for the Rajang River Basin (RRB) located in the Sarawak State of Malaysia. The changes in water bodies cropped lands, and forests were assessed based on the available remotely sensed satellite data. Supervised classification with the Maximum-Likelihood-Algorithm technique was adopted for monitoring the LULC changes using...
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Point cloud in archaeological and historical survey
PublicationIn the last decade the potential of using the point clouds in archaeological research has been noted. Therefore, a number of guidelines concerning aspects of data acquisition (resolution and format) were developed. They also included the way of searching the imaged area to identify archaeological and historical cultural heritage sites. The purpose of this research was to analyze the point cloud for selected woodland survey. Forest...
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Comparison of berry quality in highbush blueberry cultivars grown according to conventional and organic methods
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Improving methods to calculate the loss of ecosystem services provided by urban trees using LiDAR and aerial orthophotos
PublicationIn this paper we propose a methodology for combining remotely sensed data with field measurements to assess selected tree parameters (diameter at breast height (DBH) and tree species) required by the i-Tree Eco model to estimate ecosystem services (ES) provided by urban trees. We determined values of ES provided by trees in 2017 in Racibórz (a city in South Poland) and estimated the loss of ES from January 1, 2017 to March 5, 2017,...
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High-Resolution Discharge Forecasting for Snowmelt and Rainfall Mixed Events
PublicationDischarge events induced by mixture of snowmelt and rainfall are strongly nonlinear due to consequences of rain-on-snow phenomena and snowmelt dependence on energy balance. However, they received relatively little attention, especially in high-resolution discharge forecasting. In this study, we use Random Forests models for 24 h discharge forecasting in 1 h resolution in a 105.9 km 2 urbanized catchment in NE Poland: Biala River....
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Design-oriented computationally-efficient feature-based surrogate modelling of multi-band antennas with nested kriging
PublicationDesign of modern antenna structures heavily depends on electromagnetic (EM) simulation tools. EM analysis provides reliable evaluation of increasingly complex designs but tends to be CPU intensive. When multiple simulations are needed (e.g., for parameters tuning), the aggregated simulation cost may become a serious bottleneck. As one possible way of mitigating the issue, the recent literature fosters utilization of faster representations,...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublicationThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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Bibliometric analysis of artificial intelligence in wastewater treatment: Current status, research progress, and future prospects
PublicationWastewater treatment is an important topic for improving water quality and environmental protection, and artificial intelligence has become a powerful tool for wastewater treatment. This work provides research progress and a literature review of artificial intelligence applied to wastewater treatment based on the visualization of bibliometric tools. A total of 3460 publications from 2000 to 2023 were obtained from the Web of Science...
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Providing Public Space Continuities in Post-Industrial Areas through Remodelling Land/Water Connections
PublicationThis article examines the problem of urban transformation strategies applied in recent years which are based on the creation of new water areas and modification of existing ones. The research is an attempt to prove that modifications of plans of water areas and forms of their borders may play an important role in achieving the best quality public spaces in post-industrial territories. The basis for demonstrating the importance...
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Application of autoencoder to traffic noise analysis
PublicationThe aim of an autoencoder neural network is to transform the input data into a lower-dimensional code and then to reconstruct the output from this code representation. Applications of autoencoders to classifying sound events in the road traffic have not been found in the literature. The presented research aims to determine whether such an unsupervised learning method may be used for deploying classification algorithms applied to...
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Knowledge sharing and knowledge hiding in light of the mistakes acceptance component of learning culture- knowledge culture and human capital implications
PublicationPurpose: This study examines the micromechanisms of how knowledge culture fosters human capital development. Method: An empirical model was developed using the structural equation modeling method (SEM) based on a sample of 321 Polish knowledge workers employed in different industries. Findings: This study provides direct empirical evidence that tacit knowledge sharing supports human capital, whereas tacit knowledge hiding does...
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Psychological capital and happiness at work: The mediating role of employee thriving in multinational corporations
PublicationWorking in multicultural work environments of multinational corporations (MNCs) creates challenges whose expected impact on happiness is equivocal. In the following paper, we examine the relationship between psychological capital and happiness at work in the specific MNCs’ context. We assume that thriving (eudemonic well-being) at work fosters individuals’ development and enhances their happiness composed of both the affective...
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Mode vibrations of plates – experimental analysis
PublicationIn this paper results of the square MDF plate and circular saw blades examination with the use of the harmonic method to static identification of resonant frequencies and shapes of mode vibrations are presented. Obtained results reveled that for circular saws with large holes in a saw blade appeared two resonant frequencies for the same nodal number.
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Fracture mechanics model of cutting power versus widespread regression equations while wood sawing with circular saw blades
PublicationA comparison of the theoretical cutting power consumption results forecasted with the model (FM_CM model) which include work of separation (fracture toughness) in addition to plasticity and friction, and two widespread regression equations while wood sawing with circular saw blades has been described. in and cutting power consumption forecasted. In computations of the cutting power consumption during rip sawing of Scots pine wood...
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Methods of solving the Atkins equation determine shear angle with taking into consideration a modern fracture mechanics
PublicationIn the paper are presented methods of solving nonlinear Atkins equation . The Atkins equation describe shear angle with taking into account properties of material cutting. To solve Atkins equation has been used iterative methods: Newton method and simplified method of simple iteration. Method of simple iteration is presented in the form of Java application.
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Empirical verification in industrial conditions of fracture mechanics models of cutting power prediction
PublicationA comparison of experimental results obtained in the industrial conditions at a sawmill located in the Baltic Natural Forest Region (PL) and theoretical cutting power consumption forecasted with the models which include work of separation (fracture toughness) in addition to plasticity and friction has been described. In computations of cutting power consumption during rip sawing of Scots pine wood (Pinus sylvestris L.) values of...
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The influence of drying parameters on wood properties
PublicationThe influence of drying conditions on wood properties is presented. The classical approach was used to determine energetic effects (cutting forces and cutting power) of wood sawing process on the basis of the wood specific cutting resistance, material constant. Before mashining wood material (soft and hard) was dryied at various conditions using air at 25oC, air-steam meaxture at 80oC and steam at 110oC.
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The change of mechanical properties of selected wood species after drying process under various conditions
PublicationThe result of mechanical properties change of selected wood species after drying process under various parameters are presented. The global elasticity modulus and bending strength for steam dried, air-steam mixture dried and air dried samples as reference were measured. It allowed to reveal the effect of wood stream, air-steam mixture and their temperature on mechanical properties of wood. It has been recognized that steam and...
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Ultimate distortion of circular saw
PublicationW artykule przedstawiono przyczyny i efekty poprzecznego odkształcenia piły tarczowe. Przedstawiono również zależność, na podstawie której wyznaczyć można graniczną wartość odkształcenia piły tarczowej.
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Losses and raw material yield of wood saeing processes
PublicationW artykule opisano sposób wyznaczania bezwzględnych i względnych strat materiałowych, jak również wydajności materiałowej w procesie przecinania drewna.
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Computational method for determining the static stiffness of the saw blade
PublicationW artykule opisano sposób modelowania i obliczeń odkształceń i naprężeń pił tarczowych o złożonej geometrii korpusu z wykorzystaniem komputerowych programów wspomagających projektowania.
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Pro-ecological technology of wood sawing with circular saw blades
PublicationW niniejszym artykule opisano możliwości materiało- i energooszczędnego przecinania piłami tarczowymi. Przedstawiono również przykłady efektów zastosowania proekologicznych technologii przecinania w przemyśle.
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Diagnostic usefulness of granulometric analyses of chips distribution while sawing of wood
PublicationW niniejszym artykule opisano drogi transportu wiórów w procesie przecinania drewna i ich wpływ na rozdrobnienie wiórów. Przedstawiono również wyniki badań rozkładu segregacji wiórów powstających w procesie przecinania piłą o powszechnie stosowanej konstrukcji i piłą z domkniętymi rowkami wiórowymi.
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Application of gas-steam mixture for wood drying purposes
PublicationW artykule przedstawiono wyniki suszenia drewna przy zastosowaniu mieszaniny parowo-gazowej. Badania dotyczyły suszenia drewna dębowego, sosnowego i świerkowego. We wszystkich eksperymentach skrócono czas suszenia w porównaniu z suszeniem konwencjonalnym.
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The prediction method of the shear angle in the cutting zone during wood sawing
PublicationW artykule opisano metodę przewidywania kąta ścinania w strefie skrawania dla przypadku przecinania drewna. Kąt ścinania był określany z wykorzystaniem współczesnej mechaniki pękania. Nieliniowe równanie opisujące tą wielkość było rozwiązywane numerycznie za pomocą metody iteracyjnej Newton-Raphson. Otrzymane wyniki obliczeń wykazują możliwość rozszerzenia obszaru modelowania efektów energetycznych procesu przecinania drewna nawet...
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Selected mechanical properties of steam kiln-dried wood determined on the basis of cutting power
PublicationW artykule przedstawiono wyniki wiązkości oraz naprężeń granicznych przy ścinaniu drewna suszonego z użyciem pary wodnej na podstawie zmierzonych wartości mocy skrawania. Badaniom poddawano próbki dębowe oraz sosnowe pochodzące z północnych regionów Pomorza. Wykazano, że przyspieszone suszenie drewna z użyciem pary wywołuje obniżenie badanych właściwości mechanicznych, które wyznaczano z wykorzystaniem współczesnej mechaniki pękania.
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Effect of the saw blade geometry at its static stiffness
PublicationW artykule opisano wpływ wybranych parametrów piły tarczowej wpływających w istotny sposób na jej sztywność statyczną.
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Specific cutting resistance while sawing of wood - the size effect
PublicationW artykule przedstawiono wyniki analiz zmian właściwego oporu skrawania, przy zastosowaniu współczesnej mechaniki pękania z uwzględnieniem wiązkości. Analizy wykonano dla procesu przecinania drewna na pilarce ramowej PRW15M drewna jesionu i jesionu modyfikowanego termicznie. Zastosowane podejście pozwala na wyjaśnienie zjawiska wzrostu właściwego powierzchniowego oporu skrawania dla niewielkich grubości warstwy skrawanej jako efektu...
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Methods of determining cutting forces during woodcutting
PublicationW artykule przedstawiono podstawowe metody określania sił przy przecinaniu drewna, które ulegały modyfikacjom wraz z postępem wynikającym z badań nad tym procesem. Przedstawione metody podzielono na dwie grupy: podejście klasyczne oraz nowatorskie podejście z zastosowaniem mechaniki pękania, które uwzględniają różne własności mające wpływ na proces przecinania. Podejście klasyczne reprezentują metody opierające się na właściwym...
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Methodology for determination of the selected mechanical properties of wood based on cutting tests
PublicationFrom kiln-dried spruce wood (with steam) as well as in natural conditions were randomly selected 8 samples. After determining the average dimensions, moisture content and density of the samples they have been cut on the frame sawing machine PRW15M for measurement of cutting power. Based on those results from a linear rela-tionship of cutting power versus feed per toot mechanical properties of wood such as facture toughness and...
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Determination of Moisture Content Profiles of Spruce Wood After High Temperature Process and Air Drying
PublicationThe results of moisture content of wood after the process of its drying under high temperature conditions and air drying are presented. Wood samples, namely spruce (Picea abies Karst.) from the northern part of Pomerania region in Poland, were subject of steam and air drying.The aim of experiments was to measure moisture content of wood in its cross sections using moisture meter WRD-100. The samples of thickness 70 mm and length...
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The differential impact of a density of Polish pine wood on cutting forces with its origin region taken into consideration
PublicationIn the article the dependence of cutting forces in a function the density of wood with regard to the wood origin are presented. Samples used in experiment were with Scotch pine (Pinus sylvestris L.) originating from four provenances in Poland (Figure 1). Wood density was measured by two methods: stereometric method (global density) and radiometric method (local density). Stereometric method consists in measurements the volume...
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Dynamics of cutting power during sawing with circular saw blades as an effect of wood properties changes in the cross section
PublicationIn the paper the effect of the method calculation upon the cutting power is presented. In computations were used models in which fracture toughness was incorporated. The comparison concerned models as follows: FM-CM – classic model in which the sum of all uncut chip thicknesses of the simultaneously teeth engaged represented the mean uncut chip thickness, FM-FDM – full dynamical model in which besides variable uncut chip thickness...
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Simulation of wood structure geometry after machining
PublicationW niniejszym artykule została przedstawiona nowa metoda trójwymiarowych symulacji geometrii powierzchni drewna. Zaprezentowano wpływ parametrów obróbkowych oraz drgań podczas strugania obrotowego drewna. Chropowatość powierzchni była charakteryzowana poprzez parametry profilu chropowatości Ra oraz Rz. Posuw na ostrze oraz średnica narzędzia są najbardziej wpływającymi czynnikami na wielkość nierówności podczas maszynowej obróbki...
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Influence of steam drying process on wood mechanical properties
PublicationResults of influence of gas-steam mixture drying process on mechanical properties of material are presented. Wood species, namely oak (Quercus L.), beech (Fagus L.), pine (Pinus L.) and spruce (Picea K.) from the northern part of Pomerania region in Poland, were subject of air-steam mixture drying process in a laboratory kiln especially arranged for that reason. Measurements of the global coefficient of elasticity and bending strength...
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The effect of the annual growth and the late wood share upon density of the Polish pine wood as a function of its origin
PublicationW artykule przedstawiono zróżnicowanie gęstości polskiego drewna sosnowego (Pinus sylvestris L.) w zależności od udziału drewna późnego w przyroście rocznym z uwzględnieniem krainy pochodzenia drewna. Wspomniane zróżnicowanie jest w istotne statystycznie w skali globalnej oraz dla większości miejsc pochodzenia. Pomiar gęstości wykonano przy użyciu metody stereometrycznej. Metoda ta polegała na określeniu objętości pryzmy poprzez...
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The innovative experimental rig for wood steam drying at atmospheric pressure
PublicationThe high cost of fossil fuel and soaring consumer interest have encouraged people in the wood industry to look for faster and more energy-efficient methods to dry lumber. The air-steam mixture as medium of drying process was used in a laboratory kiln especially arranged for that reason. Experimental rig is based on automatic control system. At the time of drying measurements of the internal temperature, wood temperature, moisture...
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The lasting traditions of activities in the field of wood technology researches at the Gdansk University of Technology
PublicationW niniejszym artykule przedstawiono sylwetki ludzi z Politechniki Gdańskiej, którzy odeszli, jednakowoż, których działalność była znacząca w obszarze drzewnictwa i mechanicznej technologii drewna.
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On some approaches to cutting power estimation while wood sawing
PublicationW niniejszym artykule przedstawiono i porównano metody, które mogą być stosowane do szacowania mocy skrawania przy przecinaniu drewna na pilarkach tarczowych. Przy klasycznym podejściu efekty energetyczne procesu przecinania drewna piłami są obliczane na bazie właściwego powierzchniowego oporu skrawania. W internecie dostępne są narzędzia do określania mocy skrawania w postaci oprogramowania dostępnego on-line, przykładowo "Horsepower...
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Distinctive properties of Scots pine (Pinus sylvestris L.) originating from the Carpathian and Great Poland-Pomeranian of Nature and Forest Land
PublicationIn this paper values of properties of Scots pine, the fracture toughness and of shear yield stress in the shear zone are presented. Samples of Scotch pine (Pinus sylvestris L.) wood of two provenances from Poland were tested. These properties were determined from the values of cutting power obtained experimentally on the saw frame PRW-15M. The values of fracture toughness and shear yield stress based on the Atkins model for cutting...
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The selected effects of high temperature air-steam mixture wood drying
PublicationThe results of properties change of beech wood after drying process are presented. The wood taken to experiments was from northern part of Pomeranian region in Poland. Before the main high temperature drying process using air-steam mixture, wood was initially dried in an open air conditions. The high temperature drying process was conducted at temperature 120oC, humidity 48%, flow rate of drying medium 2.5m/s and atmospheric pressure....
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The effect of current signal filtering method on the value of cutting power while sawing wood
PublicationThe goal of this work was to investigate an effect of various signal pre-processings on the outline of the electrical power curve and its influence on the measured cutting force estimation. Two signal processing methods were selected for the needs of the experiment, including digital filter and wavelet transform. The filter used was Butterworth, 3rd order band-stop with the cut-out band from 45 Hz to 55 Hz. The second approach...
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XRF analysis of heavy metals contents in oak wood (Quercur robur L.)
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Initial studies on the influence of Aspergillus niger on the wood components of Populus sp.
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