Wyniki wyszukiwania - Biblioteka Nauki

1

Nowe możliwości procesów przeróbki plastycznej w warunkach wymuszonej drogi odkształcenia

100%

Grosman F. , Pawlicki J.

Hutnik, Wiadomości Hutnicze

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2005

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tom Vol. 72, nr 5

280-285

PL

Badania nad mechanizmami odkształcenia plastycznego, które bardzo intensywnie prowadzone są w wielu ośrodkach badawczych, pozwoliły na stwierdzenie istnienia takich sposobów odkształcenia, które wywołują istotne obniżenie nacisków niezbędnych do prowadzenia procesów kształtowania plastycznego oraz zwiększenie wielkości odkształceń granicznych. Przeprowadzone próby laboratoryjne ściskania i walcowania wykazały istotne różnice w charakterze przebiegu, rejestrowanych w trakcie prób, parametrów siłowych, w warunkach konwencjonalnych oraz z wymuszoną zmianą drogi odkształcenia. Efekty prowadzonych badań laboratoryjnych w postaci nowych danych na temat mechanicznej i strukturalnej reakcji metali, w warunkach kontrolowanej zmiany schematu obciążenia, są obiecujące i pozwalają na prognozowanie ich wdrożenia w warunkach przemysłowych.

EN

Research on mechanisms of plastic deformation, performed now intensively in many R&D centers, allowed to prove existence of such methods of deformation, which create significant reduction of the force values necessary for execution of metal forming and increasing the values of deformation limit. The laboratory tests made on rolling and compression have revealed some significant differences in the nature of the course of power-energy parameters registered at tests, in conventional conditions and with forced change of deformation path. Effects of executed laboratory examinations in form of the new data concerning mechanical and structural reaction of metals, in conditions of controlled change of loading pattern, are promising and encouraging for continuation of presented research work.

2

Preprocessing and Storing High - Throughput Sequencing Data

100%

Świercz A. , Bosak B. , Chłopkowski M. , Hoffa A. , Kasprzak M. , Kurowski M. , Piontek T. , Błażewicz J.

Computational Methods in Science and Technology

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2014

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tom Vol. 20, No. 1

9--20

EN

DNA sequencing is a process of recognizing DNA sequences of genomes. The process consists in reading short sequences, that are subsequences of a genome, and merging them into longer sequences, preferably the whole genome. In the first phase even billions of short sequences are read at once. To simplify and speed up the second phase, we develop a pipeline of preprocessing the initial set of short sequences that is removing low quality reads and duplicated reads.We also propose a method for preliminary joining overlapping sequences, which resulted in decreasing the cardinality of initial sets to 13.9% and 27.8%. We also examine possible ways to store the huge amount of experimental data. We compare different compression methods, from which the best appeared to be DSRC, developed for special type of text files containing short sequences and their quality. We test the parameters for TCP data transferring to find the best transfer rate.

3

An innovative ecological hybrid refrigeration cycle for high power refrigeration facility

100%

Cyklis P. , Janisz K.

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nr 3

4

Image quality index of the monochrome archival photographs’ compression

100%

Gromaszek M. , Michalik M.

Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica

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2010

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tom Vol. 10, no. 1

69--78

EN

The recent process of digitalizing archives has increased the importance of choosing the best compression method and evaluating the quality of the compressed materials. Our paper focuses on monochrome photographs. We suggest a new image quality index partly based on Human Visual System. We think that, despite its simplicity, it is equal to Mean Subjective Rank. In addition, we intend to ascertain that (the index submitted by us) our index is very easy both to understand and to implement.

5

Compressing sentiment analysis CNN models for efficient hardware processing

100%

Wróbel K. , Karwatowski M. , Wielgosz M. , Pietroń M. , Wiatr K.

Computer Science

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2020

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tom T. 21 (1)

25--41

EN

Convolutional neural networks (CNNs) were created for image classification tasks. Shortly after their creation, they were applied to other domains, including natural language processing (NLP). Nowadays, solutions based on artificial intelligence appear on mobile devices and embedded systems, which places constraints on memory and power consumption, among others. Due to CNN memory and computing requirements, it is necessary to compress them in order to be mapped to the hardware. This paper presents the results of the compression of efficient CNNs for sentiment analysis. The main steps involve pruning and quantization. The process of mapping the compressed network to an FPGA and the results of this implementation are described. The conducted simulations showed that the 5-bit width is enough to ensure no drop in accuracy when compared to the floating-point version of the network. Additionally, the memory footprint was significantly reduced (between 85 and 93% as compared to the original model).

6

Overflows of elastic traffic

100%

Głąbowski M. , Kmiecik D.

Image Processing & Communications

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2017

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tom Vol. 22, no. 1

13--26

EN

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 tere 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 bloking probabilisty In The sample elastic trafﬁcoverﬂow 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.

7

Homomorphisms Between Covering Approximation Spaces

100%

Lang G. , Li Q. , Guo L.

Fundamenta Informaticae

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2015

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tom Vol. 138, nr 3

351--371

EN

The introduction of information system homomorphisms has made a substantial contribution to attribute reduction. However, the efforts made on homomorphisms are far from sufficient. This paper further investigates homomorphisms between covering approximation spaces. First, we introduce the concepts of upper and lower homomorphisms as well as homomorphisms in order to study the relationship between covering approximation spaces. Then we present the notions of covering approximation subspaces and product spaces. We also compress covering approximation spaces and covering information systems with the aim of attribute reduction. Afterwards, by utilizing the compressions of the original spaces and systems we compress the dynamic covering approximation spaces and dynamic covering information systems. Several illustrative examples are employed to demonstrate that the homomorphisms provide an effective approach for compressing covering approximation spaces and covering information systems.

8

Numerical Modeling of Laboratory Test of Plain Concrete Under Uniaxial Impact Compression

100%

Adamczyk R. , Łodygowski T.

Engineering Transactions

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2003

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tom Vol. 51, iss.4

381-398

EN

The aim of this study is to compare experimental results of the behavior of concrete specimen, dynamically loaded in compression, carried out by P.H. Bischoff and S.H. Perry [8], with the results obtained in numerical simulation. The intention of the investigation, reported in this paper, is to create the constitutive relation for concrete that depends on impact rates. The specimen was loaded in static as well as in dynamic tests. New constitutive relation of concrete dependent on impact rate has been proposed. Accuracy of the model was studied and compared with the experiment in simple characteristics. Two cases of concrete strength 30 and 50 MPa and three initial impact rates were considered. After verification in a simple uniaxial test, the new constitutive relation has been applied in complex engineering problem. Numerical impact analysis was carried out for impact tests in the environment of the ABAQUS/Explicit finite element code, and ABAQUS/Standard for static tests [1].

9

Numeryczny sposób określenia temperatury czynnika chłodniczego po procesie sprężenia

100%

Kołoła R.

Chłodnictwo : organ Naczelnej Organizacji Technicznej

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2012

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tom R. 47, nr 5

6-8

PL

Temperatura czynnika chłodniczego po sprężeniu jest istotna wielkością w pracy układu chłodniczego. Określa ona maksymalną wartość ciśnienia możliwą do uzyskania na jednym stopniu sprężania. Ponadto określa typy możliwych do wykorzystania sprężarek, a także konieczność ich chłodzenia. Podczas prac nad symulacjami układów chłodniczych niezbędny jest sposób jej wyliczenia. W pracy zaprezentowano autorską metodą określenia temperatury na króćcu tłocznym sprężarki. Umożliwia ona stosunkowo prostą implementację do kodów numerycznych.

EN

The temperature of the refrigerant after compression is important in the size of the cooling system. It specifies the maximum pressure that can be obtained at one stage of compression. In addition, specify the types of possible use of compressors and the need of cooling. While working on simulations of cooling systems is necessary method of its calculation. The paper presents an original method for the determination of temperature on the discharge stub. It allows relatively simple implementations of numerical codes.

10

Influence of moisture content on elastic constants of Scots pine wood subjected to compression

100%

Güntekin E. , Akar S.

Drewno : prace naukowe, doniesienia, komunikaty

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2019

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tom vol. 62, nr 204

41--53

EN

Moisture content is the environmental factor that has the greatest influence on the physical and mechanical properties of wood materials. This research aimed to quantify the effect of moisture content on the elastic constants of Scots pine wood grown in Turkey under different humidity regimes. The elastic properties investigated include EL, ER, ET, GLR, GLT, GRT, ʋLR, ʋLT, ʋRL, ʋRT, ʋTL and ʋTR under compression. The compression strength in all principal directions was also studied. Specimens were cut from sapwood of pine logs and sorted into four matched MC groups. Clear wood samples were conditioned at 21°C and 45%, 65%, 85%, 95% RH, and subjected to compression tests. A biaxial extensometer was used to measure active and passive strain during loading. Young’s modulus, shear modulus, Poisson’s ratios and compression strength were calculated and compared for all orthotropic directions. The results indicate that the elastic and strength properties are significantly different in the principal directions. The Young’s modulus, shear modulus and compression strength of the tested samples were strongly affected by moisture content. These properties exhibit a linear decrease with increasing moisture content. Poisson’s ratios are not sensitive to MC changes.

11

The Results of Neurolysis In Perinatal Brachial Plexus Lesions Treatment

100%

Gosk J. , Rutowski R. , Wiâcek R. , Urban M. , Wnukiewicz W. , Reichert P.

Polish Journal of Surgery

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2010

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tom 82

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nr 10

543-546

EN

The aim of the study was to evaluate of the results of neurolysis in perinatal brachial plexus lesions treatment.Material and methods. Clinical material comprised 31 children, both sex, in age between 3 and 29 months, who had neurolysis of brachial plexus in period from 1998 to 2005. Treatment results have been evaluated in group of 26 children by commonly accepted scales. The shortest postoperative observation period lasted 4 years.Results. Good and very good function of shoulder after surgical treatment has been noted in 14 cases, good function of elbow has been noted in 21 cases. Advantageous position of forearm has been observed in 19 cases. Useful function of wrist in group of upper-middle and total lesions has been found in 18 examined children. Useful motor and sensory hand function has been observed in 7 from 11 examined children with total lesions.Conclusions. Significant compression of brachial plexus neural elements is an indication for their release (neurolysis) also in lesions which have been classified as a I and II degree in Sunderland's scale. In brachial plexus lesions with preserved macroscopic continuity of neural elements (after exclusion of avulsion lesions), intrafascicular fibrosis may be one of reasons of poor neural function improvement.

12

Biomechanical criterion for selecting cancellous bone screws: arthrodesis in the hindfoot

100%

Reihsner R. , Huber W. O. , Beer R.

Acta of Bioengineering and Biomechanics

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2007

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tom Vol. 9, nr 2

27-33

EN

The aim of the paper was to compare primary biomechanical stability of different arthrodesis screws (7.3 mm AO screw with and without washer, 6.5 mm Herbert screw and 6.5 mm Ideal Compression Screw (I.CO.S)). The work necessary to achieve an adequate compressive force with them was compared to the measurement with the AO screw with washer, because this method is for the time being the most commonly used one and is called the golden standard. Compressive force was measured indirectly, via screw tension measurement, with strain gauges method. From the measurements we calculated the work to reach a limit of 60 N and the ratios corresponding to the value of the golden standard: I.CO.S (35.2%), Herbert (89.0%), AO-screw without washer (116%). The I.CO.S showed superior results. Only in the case of extremely poor bone quality, a clear advantage of I.CO.S could be expected in practice.

13

Directed acylic graph compression of labelled trees

100%

Paries A. , Wendling L.

Machine Graphics and Vision

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1999

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tom Vol. 8, No. 2

169-174

EN

A new algorithm for compressing labelled trees is proposed in the paper. This algorithm allows to obtain a Directed Acyclic Graph (DAG) from a labelled tree in linear time. An experimental study is also given.

14

A new measurement of compressed image quality

100%

Makris P. , Vincent N.

Machine Graphics and Vision

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2000

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tom Vol. 9, No. 1/2

369-378

EN

We intend to point out the interest in using Zipf law in wide field of image analysis. We will show how it is possible to adapt it to image analysis. There are many applications; here we are concerned with the image compression field and we are more particulary focusing on a new definition of a quality measurement of an image obtained after a decompression process. First we will propose a coding mode of an image using some neighborhood of each pixel and the Zipf law will be presented. Then some significant compresions can be achieved between different images. A ststistical study of the patterns present in the image allows a characterization of the information contained in the images so that a measurement of information modification is made possible. We define two quantitative parameters, on indicates the structure of the image whereas the second indicates high content information. The example of the image of a landscape is used to illustrate the influence of the compression rate.

15

Discrete Hartley transforms in processing of medical ultrasonic images

100%

Dulęba I.

Machine Graphics and Vision

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2000

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tom Vol. 9, No. 3

729-740

EN

In this paper discrete Hartley transforms were used to filter and to compress medical ultrasonic images. The transforms are global and resemble discrete Fourier transforms, thus the butterfly algorithm, used in Fast Fourier Transform (FFT), can be utilized for thier computation. Hartley transforms offer some advantages over Fourier transforms especially when computations are performed on general-purpose computers.

16

Optimised black-and-white contour coding

100%

Turner M. J.

Machine Graphics and Vision

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2000

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tom Vol. 9, No. 1/2

397-402

EN

A hierarchical two-dimensional structural iamge segmentation algorithm based on a contour tree description is presented. This format is compared with more traditional facsimile coding standards (T.4, T.6 and T.82) (as well as other common compression standards) on the standard ITU test set of facsimile images. A detailed study of the coding complexity and choices required to design a general contour coding strategy is carried out. A final choice of parameters is presented and compared against previous work on gray-scale imagery.

17

Organized mesh design applied in the body simulation

100%

Doncescu A.

Machine Graphics and Vision

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2000

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tom Vol. 9, No. 1/2

93-102

EN

The meshing of 3D objects, when the surface of the object is a cloud of points, is realized in general by triangles using the algorithm of Delaunay. Another possibility exists via the dual algorithm, the Voronoi diagram. An alternative to the algorithm of Voronoi is proposed by the utilization of a Voronoi organized meshes. Vertices of valence 3, forming in general "hexagons" and some "plygons" compose by 5,7,8... edges to insure the curvature. An example is the fullerences. Fullerences are symetrical closed convex graphite shells, consisting of 12 pentagons and various numbers of hexagons, for which the gaussian curvature is positive. We prasent in this paper the different algorithms of subdivision and compression applied on this type of surfaces.

18

Tectonic pulse registered between 2013 and 2015 on the eastern margin of the Bohemian Massif

100%

Briestenský M. , Stemberk J. , Littva J. , Vojtko R.

Geological Quarterly

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2021

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tom Vol. 65, No. 1

art. no. 14

EN

A significant period of increased tectonics was monitored between 2013 and 2015 on the eastern margin of the Bohemian Massif along ten faults. Nine of them showed a uniform scheme: dextral strike-slip along generally NW–SE striking faults, sinistral strike-slip along generally NE-SW striking faults and uprising of the southern blocks. The distinguished fault displacements displayed an NNW-SSE striking compressional component of the stress field during this remarkable tectonic episode.

19

Investigation on compressive behavior of Cu-35Ni-15Al alloy at high temperatures

100%

Li C. , Chen J. , Li W. , Hu Y. , Ren Y. , Qiu W. , He J. , Chen J.

Materials Science Poland

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2014

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tom Vol. 32, No. 3

341--349

EN

Microstructures and mechanical properties of Cu–35Ni–15Al alloy in cast and porous states were studied by scanning electron microscopy and compression tests. The influence of porosity, deformation temperature and loading rate on mechanical properties of the two kinds of alloys was investigated. The results show that the as cast alloy and porous alloys have almost the same phase constitution: Cu rich phase, Ni rich phase and K intermetallics. The yield strength of porous alloys increases continuously with decreasing porosity, the relationship between porosity and yield stress follows Gibson-Ashby equation.With decreasing deformation temperature, the yield strength of as cast alloy and porous alloy increase. With the increase of loading rate, the yield strength of these alloys shows an increasing trend. After compression, the microstructure of as cast alloy is more uniform, and porous alloys are more prone to have localized deformations.

20

Efektywna metoda przetwarzania macierzy rzadkich

100%

Jabłoński J. , Turos J.

Pomiary Automatyka Kontrola

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2007

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tom R. 53, nr 5

63-65

PL

Wiele problemów optymalizacyjnych sprowadzanych jest do przetwarzania macierzy rzadkich o bardzo dużych rozmiarach. Tradycyjne metody operacji na macierzach o tak dużych rozmiarach jest czasochłonne dlatego poszukiwane są rozwiązania gwarantujące większą efektywność i krótszy czas przetwarzania. W artykule omówiono wybrane metody i zaproponowano autorską metodę wykorzystania kompresji w poprawie efektywności przetwarzania macierzy rzadkich.

EN

Many optimization problems can be imported to processing of thin matrices about very large sizes. The traditional methods of operation on the matrices about so it is the large sizes time-consuming therefore the guaranteeing the larger efficiency solutions be in the demand and the shorter time of processing. This paper presented the author's method of utilization in improvement of efficiency the compression of processing of sparse matrix in presented study was introduced.