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Number of results: 17
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Abstract

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstract

Chromosome numbers of 46 Hieracium L. and Pilosella Vaill. taxa from Austria, Bulgaria, Czech Republic, Macedonia, Montenegro, Poland, Romania, Serbia and Slovakia are presented. Chromosomes numbers are given for the first time for Hieracium amphigenum Briq. 2n = 3× = 27, H. bohatschianum Zahn 2n = 4× = 36, H. borbasii R. Uechtr. 2n = 4× = 36, H. cernuum Friv. 2n = 2× = 18, H. hazslinszkyi Pax 2n = 3× = 27, H. mirekii Szeląg 2n = 4× = 36, H. polyphyllobasis (Nyár. & Zahn) Szeląg 2n = 3× = 27, H. porphyriticum A. Kern. 2n = 4× = 36, H. racemosum Waldst. & Kit. ex Willd. subsp. racemosum 2n = 3× = 27, H. scardicum Borm. & Zahn 2n = 4× = 36, H. sparsum subsp. ipekanum Rech. fil. & Zahn 2n = 4× = 36, H. sparsum subsp. peristeriense Behr & Zahn, H. sparsum subsp. squarrosobracchiatum Behr & al. 2n = 3× = 27, H. tomosense Simk. 2n = 4× = 36, H. tubulare Nyár. 2n = 4× = 36, H. werneri Szeląg 2n = 3× = 27 and Pilosella fusca subsp. subpedunculata (Zahn) Szeląg, as well as five species of Hieracium sect. Cernua R. Uechtr. not described to date and a hybrid between H. bifidum s. lat. and H. pojoritense Woł
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Abstract

Chromosome numbers for 15 taxa of Hieracium L. s.str. from Bulgaria, Greece, Macedonia, Poland, Romania and Slovakia are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. vagneri Pax s.str. (2n = 4x = 36), H. wiesbaurianum subsp. herculanum Zahn (2n = 4x = 36), H. wiesbaurianum subsp. kelainephes Nyár. & Zahn (2n = 3x = 27), as well as for two undescribed species of hybrid origin between H. umbellatum L. and H. wiesbaurianum s.lat. (2n = 3x = 27), and between H. sparsum Friv. and H. schmidtii s.lat. (2n = 3x = 27), and for three undescribed species of the H. djimilense agg. (2n = 3x = 27), H. heldreichii agg. (2n = 3x = 27), and H. sparsum agg. (2n = 3x = 27). Furthermore, the chromosome numbers of two undescribed species of hybrid origin between H. umbellatum L. and H. wiesbaurianum s.lat. (2n = 3x = 27), and between H. sparsum Friv. and H. schmidtii s.lat. (2n = 3x = 27) are given. A new, tetraploid chromosome number is given for H. barbatum Tausch from the northernmost locality of the species in Europe.
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Abstract

The present work deals with population-based meiotic studies on eight species belonging to four genera of the family Commelinaceae from different regions of Kangra Valley which is well known for its rich floristic diversity. At the world level, different cytotypes for four species such as Commelina hasskarlii (2n = 22, 60), C. kurzii (2n = 60), Murdannia nudiflora (2n = 24) and M. spirata (2n = 24) have been recorded for the first time at various ploidy levels. Additionally, from India, the new chromosome count for Tradescantia pallida (2n = 24) has been reported at the tetraploid level. The course of meiosis has been found to be normal in all the populations of Commelina benghalensis, C. paludosa, Murdannia nudiflora and M. spirata while four species, Commelina hasskarlii, C. kurzii, Cyanotis cristata and Tradescantia pallida have shown a normal to abnormal meiotic course in different populations. These meiotic abnormalities have revealed a clear effect on the pollen size and pollen fertility.
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Abstract

The paper reports meiotic studies on 50 populations comprising 12 species belonging to 5 genera of Caryophyllaceae from the Western Himalayas. The chromosome numbers in Arenaria kashmirica (n=20), Silene conoidea (n=20), S. edgeworthii (n=12 and n=24), S. moorcroftiana (n=24), S. nepalensis (n=12), Stellaria media (n=13), S. monosperma (n=13) and S. semivestita (n=13) are reported for the first time. The chromosome numbers in Lychnis coronaria (n=12) and Silene vulgaris (n=24) are given for the first time from India, along with Gypsophilla ceratioides (n=15) from the Western Himalayas. The course of meiosis varies from normal to abnormal in different populations of Silene conoidea, S. edgeworthii, S. vulgaris, Stellaria media, S. monosperma and S. semivestita. The course of meiosis was abnormal in all studied populations of Lychnis coronaria. Abnormal microsporogenesis (cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges) led to reduced pollen fertility and differences in pollen grain size.
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Abstract

In November 1994 a first inventory of Tanaidacea from the Beagle Channel and at some stations of the Atlantic continental shelfwas obtained using epibenthic sledge samples. In total, 2175 specimens from 27 species of eight families of Tanaidomorpha and two families of Apseudomorpha were collected. Two species, Allotanais hirstutus (Beddard, 1886) and Apseudes heroae Sieg, 1986, strongly dominated this area. Generally low diversity and abundances were recorded for the western area of the Beagle Channel, while substantially higher values were reported at the eastern entrance on the Atlantic side of the Beagle Channel. Abundances slightly varied with depths, but not significantly.
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Abstract

Food additives, especially E numbers, are widely perceived by consumers as artificial and harmful. However, the fact is that they are an essential ingredient in numerous products, many have “natural” origins and none of them pose a risk to health.
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Abstract

Overseas mining investment generally faces considerable risk due to a variety of complex risk factors. Therefore, indexes are often based on conditions of uncertainty and cannot be fully quantified. Guided by set pair analysis (SPA) theory, this study constructs a risk evaluation index system based on an analysis of the risk factors of overseas mining investment and determines the weights of factors using entropy weighting methods. In addition, this study constructs an identity-discrepancycontrary risk assessment model based on the 5-element connection number. Both the certainty and uncertainty of the various risks are treated uniformly in this model and it is possible to mathematically describe and quantitatively express complex system decisions to evaluate projects. Overseas mining investment risk and its changing trends are synthetically evaluated by calculating the adjacent connection number and analyzing the set pair potential. Using an actual overseas mining investment project as an example, the risk of overseas mining investment can be separated into five categories according to the risk field, and then the evaluation model is quantified and specific risk assessment results are obtained. Compared to the field investigation, the practicability and effectiveness of the evaluation method are illustrated. This new model combines static and dynamic factors and qualitative and quantitative information, which improves the reliability and accuracy of risk evaluation. Furthermore, this evaluation method can also be applied to other similar evaluations and has a certain scalability.
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Abstract

Scheuchzeria palustris is a species regarded as an arctic-boreal relic and critically en-dangered. The study was conducted on one of the recent stands in the Łódź region, in the Czarny Ług Reserve, located near Wolbórz. The primary aim of the study was to know the amount of this species and the associated species. Quantitative, morphological and floristic features were ana-lysed. In the study area occurred about 150 specimens per 1 m2. Among the associated species were found species representing classes: Scheuchzerio-Caricetea Nigrae and Oxycocco-Sphagnetea. Eriopho-prum angustifolium was dominant among the first class species (60% coverage), while Andromeda polifolia and Oxycoccus palustris from the second class. From here it can be assumed that the succession will be in the direction of Scheuchzerio-Caricetea Nigrae. However, high water levels may inhibit this process. Specific biotic and abiotic conditions allow for the survival of this spe-cies. This is visible, among other things, in the mosaic structure of the studied stand.
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Abstract

Our survey of data collected in the Chromosome Number Database for Polish angiosperms indicated that the 1,498 species with chromosome counts represent 40% of the total angiosperms (3,719) occurring in Poland, including 1,205 native species (53% of native species) and 194 anthropophytes (56% of anthropophytes). The chromosome numbers are known for all native species occurring in Poland within 298 genera and 46 families, and for all anthropophytes from 79 genera and 11 families. The remaining angiosperm groups are less explored: chromosome counts from Poland are known for 9% of cultivated species and 5% of ephemerophytes. According to generic basic chromosome numbers, 46.44% of Polish angiosperms have been classified as polyploid. By three different threshold methods, the contribution of polyploid plants to the Polish flora is 64.64%, 50.89% or 42.89%. Polyploidy is more common among indigenous than non-indigenous plants, and the ploidy distribution among plants from the Polish Tatras does not differ significantly from that observed in the rest of native Polish plants.
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Abstract

This paper deals with the modelling of traction linear induction motors (LIMs) for public transportation. The magnetic end effect inherent to these motors causes an asymmetry of their phase impedances. Thus, if the LIM is supplied from the three-phase symmetrical voltage, its phase currents become asymmetric. This effect must be taken into consideration when simulating the LIMs’ performance. Otherwise, when the motor phase currents are assumed to be symmetric in the simulation, the simulation results are in error. This paper investigates the LIM performance, considering the end-effect induced asymmetry of the phase currents, and presents a comparative study of the LIM performance characteristics in both the voltage and the current mode.
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Abstract

We address one of the weaknesses of the RSA ciphering systems i.e. the existence of the private keys that are relatively easy to compromise by the attacker. The problem can be mitigated by the Internet services providers, but it requires some computational effort. We propose the proof of concept of the GPGPU-accelerated system that can help detect and eliminate users’ weak keys. We have proposed the algorithms and developed the GPU-optimised program code that is now publicly available and substantially outperforms the tested CPU processor. The source code of the OpenSSL library was adapted for GPGPU, and the resulting code can perform both on the GPU and CPU processors. Additionally, we present the solution how to map a triangular grid into the GPU rectangular grid – the basic dilemma in many problems that concern pair-wise analysis for the set of elements. Also, the comparison of two data caching methods on GPGPU leads to the interesting general conclusions. We present the results of the experiments of the performance analysis of the selected algorithms for the various RSA key length, configurations of GPU grid, and size of the tested key set.
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Abstract

The problem considered in the paper is motivated by production planning in a foundry equipped with a furnace and a casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. However, contrary to the classic approach, we assumed the fuzzy nature of the demand set for a given day. The paper describes a genetic algorithm adapted to take into account the fuzzy parameters of simultaneous grouping and scheduling tasks and presents the results achieved by the algorithm for example test problem.
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Abstract

Transverse effective thermal conductivity of the random unidirectional fibre-reinforced composite was studied. The geometry was circular with random patterns formed using random sequential addition method. Composite geometries for different volume fraction and fibre radii were generated and their effective thermal conductivities (ETC) were calculated. Influence of fibre-matrix conductivity ratio on composite ETC was investigated for high and low values. Patterns were described by a set of coordination numbers (CN) and correlations between ETC and CN were constructed. The correlations were compared with available formulae presented in literature. Additionally, symmetry of the conductivity tensor for the studied geometries of fibres was analysed.
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Abstract

Dynamic Mine disasters can be induced by the instability and failure of a composite structure of rock and coal layers during coal mining. Coal seam contains many native defects, severely affecting the instability and failure of the compound structure. In this study, the effects of coal persistent joint on the strength and failure characteristics of coal-rock composite samples were evaluated using PFC2D software. The results show that with the increase of included angle α between the loading direction and joint plane direction, the uniaxial compressive stress (UCS) and peak strain of composite samples first decrease and then gradually increase. The elastic moduli of composite samples do not change obviously with α. The peak strain at α of 45° is the lowest, and the UCS at α of 30° is the smallest. This is inconsistent with theoretical analysis of lowest UCS at α of 45°. This is because that the local stress concentration caused by the motion inconformity of composite samples may increase the average axial stress of upper wall in PFC2D software. Moreover, the coal persistent joint promotes the transformation from the unstable crack expansion to the macro-instability of composite samples, especially at α of 30° and 45°. The majority of failures for composite samples occur within the coal, and no obvious damage is observed in rock. Their failure modes are shear failure crossing or along the coal persistent joint. The failure of composite sample at α of 30° is a mixed failure, including the shear failure along the persistent joint in coal and tensile failure of rock induced by the propagation of coal persistent joint.
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Abstract

A spinal code is the type of rateless code, which has been proved to be capacity- achieving over both a binary symmetric channel (BSC) and an additive white Gaussian noise (AWGN) channel. Rateless spinal codes employ a hash function as a coding kernel to generate infinite pseudo-random symbols. A good hash function can improve the perfor- mance of spinal codes. In this paper, a lightweight hash function based on sponge structure is designed. A permutation function of registers is a nonlinear function. Feedback shift registers are used to improve randomness and reduce bit error rate (BER). At the same time, a pseudo-random number generator adopts a layered and piecewise combination mode, which further encrypts signals via the layered structure, reduces the correlation between input and output values, and generates the piecewise random numbers to compensate the shortcoming of the mixed linear congruence output with fixed length. Simulation results show that the designed spinal code with the lightweight hash function outperforms the original spinal code in aspects of the BER, encoding time and randomness.
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Abstract

The purpose of this article is to develop a multicriteria group decision making (MCGDM) method in dual hesitant fuzzy (DHF) environment by evaluating the weights of the decision makers from the decision matrices using two newly defined prioritized aggregation operators based on score function to remove the inconsistencies in choosing the best alternative. Prioritized weighted averaging operator and prioritized weighted geometric operator based on Einstein operations are described first for aggregating DHF information. Some of their desirable properties are also investigated in details. A method for finding the rank of alternatives in MCGDM problems with DHF information based on priority levels of decision makers is developed. An illustrative example concerning MCGDM problem is considered to establish the application potentiality of the proposed approach. The method is efficient enough to solve different real life MCGDM problems having DHF information.
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