bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time usage and efficiency of machinery during stump crushing
Authors: Gałęzia Tomasz 
Published: May 2018

Abstract
This study was carried out at a roadside landing of the Augustów Forest District in order to determine the structure of a typical working day for machines involved in stump crushing as well as the overall efficiency of the process and the machinery's fuel consumption. The machines involved in the entire process were a front-loader, a shredder, a screen and a truck-tractor unit.
Machinery activity was recorded using a sampling method with a three-minute interval. During 16 hours of observation, 533 stumps were crushed to produce 362 m3 lv of timber particles in total and the average operational productivity reached 28 m3 lv h−1. Based on the amount of consumed fuel and its energy content, the energy input of the process was calculated to be 103.33 MJ m−3 lv which is 3640.53 MJ m−3 lv less than the output of energy gained at the power plant. Total CO2 emissions of the processing machinery and transport off the forest site were estimated using previously published data and amounted to 7.58 kg m−3 lv.
The effect of natural disasters on the timber market
Authors: Sikora Adam Tomasz 
Published: May 2018

Abstract
The aim of the study was to determine the impact an increased wood supply from the Beskid forests after natural disasters on the timber economy of the Węgierska Górka Forest District and its surroundings in the years 2004–2010. The analysis was based on the wood raw material sales recorded in the database of the State Forestry Information System (SILP). Information on the buyers'location and their main use for the raw material were obtained through the Central Statistical Office. Furthermore, wood material buyers were classified according to the Polish Classification of Activities (PCA) based on the year 2007, using only a subjective analysis designed for enterprises and other economic units in the national economy.
Changes in sales of wood material to the selected buyer groups were investigated using statistical analyses of linear trends. A Pearson's correlation analysis verified the relationships between the buyer groups and the supply of timber assortments by the Węgierska Górka Forest District. Other studies have also shown that an increased supply of raw material in the context of natural disasters affects the types of wood buyers and their location. In addition, they have shown an increase in interest towards the purchase of raw materials among buyers engaged in the wholesale trade of wood and other non-wood producers which in turn decrease the share purchased by sawmills.
Continuum of floristic composition between two plant communities – Carici elongatae-Alnetum and Fraxino-Alnetum
Authors: Czapiewska Natalia , Paź Sonia , Dyderski Marcin K. , Jagodziński Andrzej M. 
Published: May 2018

Abstract
One of the crucial debates in vegetation ecology is whether plant communities are discontinuous, distinguishable units or whether they change continuously. Phytosociology assumes discontinuity and its methodology requires subjective sampling during vegetation inventories. For that reason, some researchers argue that phytosociology artificially creates discontinuity among plant communities. Our aim was to assess the continuity between ash-alder riparian forest (Fraxino-Alnetum), and alder swamp forest (Carici elongatae-Alnetum), and to check whether discontinuity observed between these two plant associations is an effect of subjective sample plot choice. We conducted 57 phytosociological relevés within a regular grid covering potential sites of both plant communities. All relevés were arranged in order of decreasing relative cover of the diagnostic species for each plant association resulting in a gentle gradient, indicating a continuous transition from Fraxino-Alnetum to Carici elongatae-Alnetum. Similar results were obtained by detrended correspondence analysis. The proportion of species from the Querco-Fagetea class, typical to Fraxino-Alnetum, was decreasing with increasing proportion of species from the Alnetea glutinosae class, typical to Carici elongatae-Alnetum. This shift followed a gradient of ecological light-moisture indicator values. Our results confirmed continuous transition between two plant communities and led us to the conclusion that discontinuity resulted from the standard sampling protocol used in classical phytosociology. This protocol, however, is useful in searching for typological patterns, required for classification of plant communities, which is the main aim of phytosociology. Nevertheless, it does not provide full insight into the variability of vegetation and introduces uncertainty when trying to understand ecosystem dynamics. This uncertainty should be taken into account when phytosociological data are used for nature conservation recommendations and to draw conclusion about vegetation dynamics.
Mammals in the diet of tawny owlStrix alucoin western part of Skierniewice Forest District (central Poland)
Authors: Gryz Jakub , Krauze-Gryz Dagny 
Published: May 2018

AbstractThe aim of the study was to describe the species diversity of small mammals in the western part of the Skierniewice Forest District (Central Poland) using tawny owl (Strix aluco) pellets. The landscape itself is a field and forest mosaic with small forest complexes. Four forest complexes with an area between 70 and 750 ha and surrounded by arable lands as well as loosely scattered buildings were chosen to carry out our work in. Owl pellets were collected in the years 2014–2016 and examined for small mammal remains employing standard protocols.Altogether, we identified 963 items belonging to 17 different mammalian prey species. The most numerous was the yellow-necked mouse,Apodemus flavicollis, which accounted for 33.5% of all identified items. As the second most important group, voles (Microtusspp.) accounted for 12.8% of all identified mammals. Unfortunately, we were unable to find species considered rare in central Poland, i.e. hazel dormouse,Muscardinus avellanarius, European water vole,Arvicola amphibiusand field vole,Microtus agrestis.In overall, the species composition of small mammal assemblages in the studied area was similar to adjacent regions.
Comparing natural regeneration of Norway spruce Picea abies (L.) Karst. in the Kaszuby Lake District and in the other regions of northern Poland
Authors: Szydlarski Marcin , Modrzyński Jerzy , Stopiński Mateusz , Majewski Michał , Maras Krzysztof 
Published: May 2018

Abstract
The paper investigates the biometric characteristics natural Norway spruce (Picea abies (L.) Karst.) regeneration in the Kaszuby Lake District, which is beyond the acknowledged Norway spruce range, with the natural regeneration in the Augustów Forest situated deep within the natural range, Warmia, at the edge of the natural range and in the West-Pomerania Lake District far beyond the natural range.
For each region, four tree stands with similar light conditions on the forest floor were selected, including two cambisols and two brunic arenosols. All sites contained naturally regenerating spruces 16–17 years of age.
The features of the forest stand and the biometric features of the saplings were determined for the selected stands on circular research plots. Altogether, the characteristicts of 400 saplings (100 in each region) were measured and analyzed using basic descriptive statistics. ANOVA with the Tukey’s multiple comparison test was performed to compare the features of forest stands and the natural regeneration of spruce in each region. The degree of interrelation between regeneration features was described by Pearson’s, ‘r’ factor or Spearman’s rank correlation coefficient. A discriminatory analysis was carried out to determine the set of regeneration features differentiating regions from each other.
The features of regeneration that differed between regions the most were: height of regeneration, basal diameter, mean height increment, and mean basal diameter increment of the saplings. The parameters for Warmia and the West-Pomerania Lake District were similar. The Augustów Forest showed the lowest values for the regeneration parameters, while the Kaszuby Lake District produced the highest values. The regeneration in the Kaszuby Lake District was markedly different from all other regions as indicated by more dynamic growth. Additionally, this population shows a great distinctness, indicating adaptation to local environmental conditions, which may be proof for the insular presence hypothesis of spruce in this region.
Due to their good quality, spontaneously developing natural regenerations in the Kaszuby Lake District should be supported by appropriate cutting and silvicultural measures.
Cost analysis of artificial and natural oak regeneration in selected forest districts
Authors: Kaliszewski Adam 
Published: May 2018

Abstract
The aim of the paper is to present the results of a cost analysis for artificial and natural oak regeneration in selected forest districts in Poland. This research was conducted in six forest districts with a high share of natural oak regeneration, located in south-western and central Poland. Altogether 65 plots with artificial and 35 plots with natural regeneration were analysed based on the extent of silvicultural (weeding, blank-filling and pre-commercial thinning) and protective measures (chemical and mechanical wildlife damage control, fencing) performed on the regenerated areas for the six years following forest regeneration. An intensity ratio (i.e., a proportion of the area of measures to the area of forest regeneration) as well as the mean unit costs of the measures and mean costs of the measures per hectare of forest regeneration were calculated.
The results show that the total costs of silvicultural and protective measures in natural oak regeneration were considerably lower as compared to artificial regeneration. The cumulative average costs during 6 years (without costs of fencing) amounted to 1216 PLN/ ha and 6543 PLN/ha for natural and artificial regeneration respectively. Lower costs of natural oak regeneration resulted from the complete lack of expenditures on seedlings and planting, a considerably lower weeding intensity, scarce blank-filling, and the absence of mechanical wildlife damage control measures. Nonetheless, natural regeneration generated higher costs for pre-commercial thinning due to its higher intensity, earlier initiation, and higher unit costs compared to artificial regeneration, as well as chemical wildlife damage control measures, for which the unit costs were higher by over 50%. However, the higher costs of pre-commercial thinning and chemical control measures did not significantly affect the measurable financial benefits of natural regeneration.
In conclusion, the matter of financial viability of natural oak regeneration should be explored in more detail over longer time spans.
Assessment of tree vitality, biomass and morphology of Scots pine (Pinus sylvestris L.) root systems growing on reclaimed landfill waste after zinc and lead flotation
Authors: Pietrzykowski Marcin , Woś Bartłomiej , Pająk Marek , Likus-Cieślik Justyna 
Published: May 2018

Abstract
The stability of introduced stands depends not only on aboveground but also on the belowground biomass. Results from reclaimed sites often indicate good growth of the aboveground part of stands, but data on the development of root systems are still lacking. Our aim was to assess the vitality of trees, their biomass and the morphology of the root systems of Scots pine (Pinus sylvestris L.) introduced on reclaimed landfill waste after zinc and lead flotation in Bukowno (southern Poland). The landfill site was reclaimed 20 years ago and reclamation treatments involved isolation and covering with mineral substrate layers (110–150 cm thickness) which formed a technogenic soil profile. Four research plots (10 m × 10 m) were set up in pure pine stands where soil profiles consisted entirely of flotation waste. Trees on the plots were assayed according to the Kraft and IUFRO classification system. In total, 15 trees of average growth parameters and bio-sociological position (I and II Kraft class) were selected for biomass and root system analyses and the root systems were excavated, washed, measured, weighed and photographed.
Our results support pine as a useful species in reforestation of post-mining areas. However, although pine trees were characterised by good vitality, their root systems were shallow and their depth reduced by up to 60 cm due to strong skeletal loamy substrate. Individual root biomass ranged from 1.2 to 9.1 kg and was comparable to pine root biomass on other reclaimed mining sites. This indicates that during restoration, the thickness of the substrate covering the flotation waste should be increased or the amount of skeletal substrate in the top layers of technosol reduced.
Observation of a Western Barbastelle Barbastella barbastellus (Chiroptera: Vespertilionidae) in new ‘crevice’ boxes for bats
Authors: Rachwald Alek , Gottfried Iwona , Tołkacz Katarzyna 
Published: May 2018

Abstract
A Western Barbastelle, Barbastella barbastellus (Chiroptera: Vespertilionidae, Schreber, 1774), was observed to inhabit ‘crevice’ bat boxes very late in the year. In November 2016, in two out of three study areas, a small number of Western Barbastelle specimens, five individuals and one individual respectively, were observed inhabiting bat boxes at night temperatures below zero and with snow cover. The occurrence of this species in summer-type hiding places during winter weather conditions has not been reported previously in Poland.
Insects mining leaves of English oak Quercus robur L. in Bydgoszcz and its vicinity
Authors: Wrzesińska Danuta 
Published: May 2018

Abstract
This research on the occurrence of insects mining leaves of the English oak Quercus robur was performed between 2011–2012 in Bydgoszcz and in nine neighbouring sites: seven in forest areas and two in an urbanized environment. The analysis of the gathered material revealed the occurrence of insects from three different orders, Coleoptera, Hymenoptera and Lepidoptera, and 10 families: Curculionidae, Tenthredinidae, Bucculatricidae, Coleophoridae, Eriocraniidae, Gracillariidae, Heliozelidae, Incurvariidae, Nepticulidae and Tischeriidae. In total, 21 insect species were collected from Q. robur; most of them at forest sites. A slightly lower number of species was recorded at Janowo, where oaks were growing on the edge of the forest in the vicinity of a transport route with heavy traffic. Even fewer taxa were observed in the vicinity of urbanised areas; in the city park on the Bydgoszcz Canal and in Fordon.
The most abundant species on the English oak were Tischeria ekebladella (Bjerk.) and Phyllonorycter heegeriella (Zell.).
The Białowieża Forest controversy in the light of the world dispute in conservation biology
Authors: Witkowski Zbigniew 
Published: May 2018

AbstractThe controversy between naturalists and foresters on the management of the Białowieża Forest is one of numerous disputes in conservation biology. Cause of the dispute is a difference in stand-point on the purpose of nature conservation. Biocentrists (Soulé 1985) argue that the only goal should be to preserve natural processes as well as endangered ecosystems and species. Anthropocentrists on the other hand (Kareiva, Marvier 2012) support conservation as a need of mankind, that is, the sustainable support of ecosystem services with the protection of species and ecosystems simply being a side effect. Another important factor in the dispute is the management of bark beetle mass outbreaks. Foresters try to control this by removing the infested trees, but naturalists protest against this practice. However, in 2013, the European Commission clearly presented its statement in this regard (EU Guidelines on Wilderness in Natura 2000); and thus, the dispute has only shown that none of the debating parties are familiar with the EU guidelines.According to the author, the more serious problem of messy organization of the Białowieża Forest conservation is rarely raised in the dispute. Multiple protected areas were established in the forest based on six different law forms for nature conservation and two forms of international origin. Such surplus of forms and areas leads to chaos and hinders the management of this valuable area.
Evaluation of the Clinical Learning Experience of Nursing Students: a Cross-Sectional Descriptive Study
Authors: Gurková Elena , Žiaková Katarína 
Published: May 2018

AbstractThe purpose of the cross-sectional descriptive study was to explore and compare the students’ experiences of the clinical environment and supervision in Slovakia. Students’ clinical learning experience were measured by the valid and reliable clinical learning instrument. A higher frequency of successful supervisory experience was found in the universities which provided accredited mentor preparation programmes or courses and individualised supervisory approaches. Frequency of supervision meetings, the occupational title of a supervisor and mainly the supervision model have an association with students ‘perceptions of different domains of clinical learning environment. The duration of the placement was not related to students’ experience and perceptions of the learning environment. Slovak students reported higher score regarding the quality of nursing care or ward culture than in the supervisory relationships between students, clinical and school staff. Further studies in this field, extended to different Eastern European countries and clinical settings, may help us to understand factors affecting workplace training.
Lie Symmetry Analysis of Boundary Layer Stagnation-Point Flow and Heat Transfer of Non-Newtonian Power-Law Fluids Over a Nonlinearly Shrinking/Stretching Sheet with Thermal Radiation
Authors: Layek G.C. , Mandal Bidyut , Bhattacharyya Krishnendu , Banerjee Astick 
Published: May 2018

Abstract
A symmetry analysis of steady two-dimensional boundary layer stagnation-point flow and heat transfer of viscous incompressible non-Newtonian power-law fluids over a nonlinearly shrinking/stretching sheet with thermal radiation effect is presented. Lie group of continuous symmetry transformations is employed to the boundary layer flow and heat transfer equations, that gives scaling laws and self-similar equations for a special type of shrinking/stretching velocity (

c

x

1

/

3

$c{x^{1/3}}$

) and free-stream straining velocity (

a

x

1

/

3

$a{x^{1/3}}$

) along the axial direction to the sheet. The self-similar equations are solved numerically using very efficient shooting method. For the above nonlinear velocities, the unique self-similar solution is obtained for straining velocity being always less than the shrinking/stretching velocity for Newtonian and non-Newtonian power-law fluids. The thickness of velocity boundary layer becomes thinner with power-law index for shrinking as well as stretching sheet cases. Also, the thermal boundary layer thickness decreases with increasing values the Prandtl number and the radiation parameter.
Overflows of Elastic Traffic
Authors: Głąbowski Mariusz , Kmiecik Damian 
Published: May 2018

Abstract
This article presents the results of a study on hierarchical multiservice traffic overflow systems. The systems under investigation were composed of a number of primary resources and one alternative resource. Traffic in the considered systems was generated with the assumption that there was a finite number of traffic sources in individual classes. Further assumption was that offered traffic is elastic traffic for which – with an increase of the load of the system – a change in the volume of allocated resources is possible followed by concurrent extension of their service time. The article includes the results that present the blocking probability in the sample elastic traffic overflow systems. The study focuses on a determination of the influence of the traffic intensity, volume of resources, degree of compression, resource with compression (primary resources, alternative resources) and the cardinality of traffic sources on values of the blocking probability in individual call classes and on the number of calls that overflow to the alternative resource.
SDN-Based WAN Optimization: PCE Implementation in Multi-Domain MPLS Networks Supported By BGP-LS
Authors: Rzym Grzegorz , Wajda Krzysztof , Chołda Piotr 
Published: May 2018

Abstract
In order to provide efficient and flexible resource management and path set-up in high-speed MPLS/GMPLS networks, the PCE (Path Computation Element) architecture was proposed by IETF. Implementation of a central module for the path set-up enables network operators to run path establishment operations for applications with explicitly defined objective functions and QoS requirements.
The paper reports on recent research and experimental investigations with PCE-based path computation performed according to the 3- layered traffic engineering (TE) system consisting of: (1) a PCE module equipped with the IBM Cplex LP solver used in the highest layer 3, and (2) a SDN controller in the intermediate layer 2 responsible for transferring path setup requests towards virtual routers in the lowest layer 1.
The presented results show usefulness of the PCE-supporting architecture with an SDN controller and applicability of bandwidth-oriented optimization based on real-time focused constraints (path delay limits). We emphasise that even a simple optimization approach shows the power provided by the SDN, i.e., flexibility of flows. This property is in practice not feasible in classical IP or MPLS networks, that is the usage of flow-based routing provided by network programmability really opens opportunities in network tuning
Multi Criterion Multicast Routing Algorithm Comparison for Large Networks
Authors: Stachowiak Krzysztof 
Published: May 2018

Abstract
QoS enabled multicast routing is known to be of non-polynominal complexity, which leads to the necessity of using heuristic algorithms to find sub-optimal solutions to the problems of this class. The evaluation of such algorithms requires the use of the simulation techniques as the heuristics’ results are of stochastic nature. Because of the problem complexity the simulation times increase significantly in the function of the network size, therefore the results presented in the literature are often limited to only small models. In this article the results of the evaluation of different multicast QoS routing algorithms (further referred to as the Multi-Constrained Minimum Steiner Tree Problem - MCMST) have been presented for a wide range of network sizes reaching thousands of nodes.
The Impact of Selected Parameters on the Performance of Routing Protocols in Wireless Sensor Networks
Authors: Piechowiak Maciej , Zwierzykowski Piotr , Kotlarz Piotr , Żmudziński Piotr 
Published: May 2018

Abstract
The aim of the article was to compare the effectiveness of the selected routing protocols for wireless sensor networks taking into account a number of specific parameters as network troughput, packet error rate and message buffer capacity for different network topologies. The simulation research was conducted in open source OMNeT++ environment. In order to achieve the assumed requirements, four different-sized network topologies were established and AODV and DYMO routing protocols were adapted.
Comparison of Selected Methods for Detecting a Reference Element using Key Points in Static Images
Authors: Kulawik Joanna 
Published: May 2018

AbstractThe article presents a possible way to detect key points. The tests were carried out by the case of detection of a reference object in static images. For comparative purposes, Chris Harris & Mike Stephens [11] and Speeded-Up Robust Features (SURF) detectors [2, 3] were used. The descriptors were built based on the Fast Retina Key point (FREAK) [1, 16] and SURF algorithms [2, 3]. Six different configurations of key point detection methods with the above descriptors were implemented. The obtained results have been presented on exemplary images and in the table. They show that this type of detection of an element of interest can be successful and should be developed.