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1

Minimalizacja zjawiska dyspersji kątowej w sieciach komórkowych 5G

Kelner Jan M., Ziółkowski Cezary

Elektronika : konstrukcje, technologie, zastosowania

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2019

|

Vol. 60, nr 2

13--20

PL

Współczesne systemy komórkowe bazują na technologii LTE, czyli standardu czwartej generacji (4G). Obecnie trwają pracę nad zakończeniem standardu definiującego systemy piątej generacji (5G), które będą implementowane w najbliższych latach. Nowa generacja systemów dotyczy już nie tylko sieci komórkowych ale również innych systemów łączności bezprzewodowej, od Internetu rzeczy, przez sieci Wi-Fi, po łączność satelitarną. Technologie 5G zrewolucjonizują całą łączność bezprzewodową zapewniając jednocześnie kompatybilność wsteczną. Jednymi z kluczowych technologii 5G są efektywne technologie antenowa, tzn. massive-MIMO oraz elektroniczne sterowanie wiązką. Ich zastosowanie w przyszłych stacjach bazowych makro-komórek pozwoli na przestrzenne zdywersyfikowanie zasobów radiowych. Technologie te pozwalają na generowanie bardzo wąskich wiązek radiowych, dzięki czemu zapewniają przestrzenną filtrację składowych sygnału emitowanych przez antenę nadawczą oraz docierających do anteny odbiorczej w środowiskach wielodrogowych. W artykule przedstawiono problematykę minimalizacji zjawiska dyspersji kątowej w sieciach 5G na bazie badań symulacyjnych. W tym celu wykorzystano wieloeliptyczny model propagacyjny.

EN

Modern cellular systems are based on the LTE technology, i.e., fourth generation (4G) standard. Currently, works on the standard defining fifth generation (5G) systems is underway, which will be implemented in the coming years. The new system-generation applies not only to cellular networks but also to other wireless communication systems, from the Internet of Things, through Wi-Fi networks, to satellite communications. 5G technologies will revolutionize all wireless connectivity while providing backward compatibility. One of the key 5G technologies are efficient antenna technologies, i.e., massive-MIMO and beamforming. Their use in future macro-cell base stations will allow spatial multiplexing of radio resources. These technologies allow the generation of radio narrow-beams, thus providing spatial filtration of the signal components emitted by the transmitting antenna and reaching the receiving antenna in multipath environments. The paper presents issues of minimizing the angular dispersion in 5G networks based on simulation studies. For this purpose, a multielliptical propagation model is used.

2

On real order passivity

Gallegos J. A., Duarte-Mermoud M. A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 3

445--454

EN

The aim of this paper is to show that a real order generalization of the dissipative concepts is a useful tool to determine the stability (in the Lyapunov and in the input-output sense) and to design control strategies not only for fractional order non-linear systems, but also for systems composed of integer and fractional order subsystems (mixed-order systems). In particular, the fractional control of integer order system (e.g. PI? control) can be formalized. The key point is that the gradations of dissipativeness, passivity and positive realness concepts are related among them. Passivating systems is used as a strategy to stabilize them, which is studied in the non-adaptive as well as in the adaptive case.

3

The Influence of Vegetation Structure on the Composition of the Seed Rain and Seedling Pool in Abandoned Molinion caeruleae Meadows

Kostrakiewicz-Gierałt K.

Polish Journal of Ecology

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2017

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Vol. 65, nr 2

269--284

EN

The investigations of the effect of different habitat conditions on the composition of the seed rain and seedling pool were conducted in the years 2014 and 2015 in abandoned patches of Molinion caeruleae dominated by small-stature meadow taxa (patch I), tall-growing grasses (patch II), as well as shrubs and trees (patch III). Observations showed that along the successional gradient the seed rain and seedling pool diminishes. The prevalence of perennials and native taxa in the seed rain and seedling pool occurred in all the study sites. Moreover, in the propagule and seedling pools of all the patches hemicryptophytes and meadow taxa prevailed but their number decreased in successional sites. Also, the abundance of ruderal and grassland taxa decreased gradually, at expense of number of forest species. Zoochorous species prevailed in the seed rain and seedling pool of all patches. Number of hydrohorous species decreased in successional patches, while the abundance of species with other dispersal modes were similar. Irrespective of patch character, the species producing propagules with medium size dominated in the seed rain and seedling pools, whereas a significant decrease of number of small-seeded species was noticed only in the seedling pool. Despite the diminishing of the seed rain and seedling pool along the successional gradient, the gap creation might be a very effective way of active protection of Molinion caeruleae meadows. However, the gap colonisation requires permanent monitoring to avoid further spreading of undesired taxa.

4

Modeling of particle radiation interaction in solid fuel combustion with artificial neural networks

Gronarz T., Habermehl M., Kneer R.

Journal of Power Technologies

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2016

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Vol. 96, nr 3

206--211

EN

In the present investigation, artificial neural networks are applied to model scattering and absorption properties occurring in particle radiation interaction for numerical simulation of pulverized coal combustion. To determine averaged scattering and absorption properties, an averaging procedure over spectral incident radiation profile and particle size distribution is applied. These averaged properties then are approximated by means of an artificial neural network. A study to determine a suitable network architecture is performed.

5

Cellular automata model for prediction of crack initiation and propagation in hot forging tools

Rauch L., Chmura A., Gronostajski Z., Polak S., Pietrzyk M.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 3

437--447

EN

The paper presents design and implementation of the cellular automata (CA) model, which predicts damage of forging tools due to fatigue. The transition rules for the model were developed on the basis of known information regarding crack initiation and propagation. The coefficients in the model were determined by the inverse analysis of the thermal fatigue tests performed on the Gleeble 3800 simulator and in the special device with a rotating disc. The CA model was coupled with the conventional abrasive wear model. The layers of cell in the CA space, which are in contact with the workpiece, were removed successively following the abrasive wear of the tool. The CA model was connected with the finite element (FE) programme, which simulates stresses in tools during forging. Since this multiscale approach appeared to be extremely demanding as far as computing times are considered, an efficient implementation of the model on heterogeneous hardware architectures was prepared. Results of simulations were compared with the industrial data and good predictive capabilities of the model were confirmed.

6

Analysis, design and applications of rotational friction dampers for seismic protection

Mualla I., Belev B.

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

|

2015

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z. 62, nr 4

335--346

EN

The paper introduces the basic types of damping devices and summarizes the benefits of implementing supplemental damping systems for seismic protection of buildings and other structures. A novel damper device based on the rotational friction hinge concept invented by the first author is described. The slip capacity of the device and its energy dissipation capacity can be easily increased by adding more layers of steel plates and friction pads. The experimental evaluation of the original damper unit was first carried out in DTU, Denmark under displacement and forcing frequency control. The friction pads were made from advanced material capable of sustaining up to 400 cycles without property degradation. In 2001, an international team including the authors conducted intensive research program on a three-storey building equipped with rotational friction dampers at the large-scale shake-table testing facility of the NCREE, Taiwan. The performance of the damped structure was examined for 14 cases of seismic input with peak ground acceleration (PGA) varying from 0.05g to 0.30g. The testing demonstrated the remarkable efficiency of the damping system for reducing the lateral displacements and interstorey drifts of the test building. Nonlinear time-history analyses were used for predicting the dynamic response of the structure and selecting adequate damper capacities. A few representative applications of RFDs for seismic protection of buildings and facilities in Europe and Japan are given which demonstrate the reliability of the devices and their most typical arrangements within new and existing structures. It is concluded that the displacement-dependent dampers such as friction and metallic are a powerful and nonexpensive engineering tool for solving vibrational problems both in new and existing structures.

PL

W artykule przedstawiono podstawowe typy urządzeń tłumiących i podsumowano korzyści z zastosowania dodatkowych systemów tłumiących w celu sejsmicznej ochrony budynków i innych konstrukcji. Opisano nowatorskie urządzenie tłumiące, wymyślonego przez pierwszego autora, bazujące na koncepcji tarcia obrotowego w przegubie. Zdolność do poślizgu urządzenia i jego zdolność do dyssypacji energetycznej może być łatwo zwiększana przez dodawanie kolejnych warstw blach stalowych i podkładek ciernych. Doświadczalna ocena prototypu urządzenia tłumiącego, pod kątem przemieszczeń i częstości drgań wymuszonych, została przeprowadzona w DTU, w Danii. Podkładki cierne zostały wykonane z zaawansowanego technologicznie materiału zdolnego wytrzymać do 400 cykli obciążenia bez degradacji swoich właściwości. W 2001 roku międzynarodowy zespół, w skład którego wchodzili również autorzy, przeprowadził intensywny program badawczy na trzykondygnacyjnym budynku, wyposażonym w tłumiki obrotowo cierne na stole wibracyjnym dużej skali obiekcie testowym NCREE, na Tajwanie. Przygotowaną Konstrukcję z tłumikami badano dla 14 przypadków obciążeń sejsmicznych ze szczytowymi wartościami przyśpieszenie ziemi (PGA) w granicach 0.05 g do 0.30 g. Badania wykazały niezwykłą efektywność systemu tłumiącego w redukcji giętnych przemieszczeń i przesunięć międzykondygnacyjnych w badanym budynku. Do określenia odpowiedzi dynamicznej konstrukcji i dobrania odpowiedniej mocy tłumika zostały użyte nieliniowe analizy przebiegów czasowych. Zaprezentowano kilka przykładowych zastosowań RFDs w celu sejsmicznego zabezpieczenia budynków i obiektów w Europie i Japonii, wykazując niezawodność urządzeń i ich najbardziej typowe układy wewnątrz nowych i istniejących budynków. Na koniec stwierdzono, że tłumiki związane z przemieszczeniami takimi jak tarcie są potężnym i niedrogim narzędziem inżynierii dla rozwiązywania problemów drgań zarówno w nowych jak i istniejących konstrukcjach.

7

Badanie chropowatości powierzchni gładkich za pomocą skaterometru kątowego. Cz. 1, Metoda pomiaru : przyrząd pomiarowy

Pawlata A.

Biuletyn Wojskowej Akademii Technicznej

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2015

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Vol. 64, nr 1

47-58

PL

W artykule opisano podstawowe parametry chropowatości powierzchni. Przedstawiono metodę obliczenia tych parametrów dla powierzchni gładkich na podstawie pomiaru funkcji BSDF charakteryzującej rozproszenie z badanej powierzchni. Opisano zbudowany w IOE WAT zautomatyzowany skaterometr kątowy służący do pomiaru powyższych parametrów.

EN

The basic parameters of surface roughness are described in this article. The method of calculation of these parameters from measurement of BSDF function characterizing scatter from surface is shown. Automated angle scatterometer, built at the Institute of Optoelectronics of the Military University of Technology (IOE MUT), used for measurements of above parameters is described.

8

Badanie chropowatości powierzchni gładkich za pomocą skaterometru kątowego. Cz. 2, Metodyka pomiaru : wyniki pomiarowe wybranych powierzchni

Pawlata A.

Biuletyn Wojskowej Akademii Technicznej

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2015

|

Vol. 64, nr 1

59-78

PL

W artykule opisano metodykę pomiaru parametrów chropowatości powierzchni za pomocą zbudowanego w IOE WAT zautomatyzowanego skaterometru kątowego. Zaprezentowano wyniki pomiarowe dla trzech wybranych polerowanych powierzchni: z krzemu, z germanu oraz ze stali nierdzewnej. Przedstawiono badania porównawcze wykonane za pomocą scatteroscope SCAT-4. Oszacowano powtarzalność pomiaru i zakres pomiarowy dla skaterometru kątowego.

EN

The experimental procedure for measurements of smooth surface roughness parameters using automated angle scatterometer, built at the Institute of Optoelectronics (IOE), is described. The results of measurements and their analysis for three chosen polished surfaces: silicon, germanium, and stainless steel are presented. The comparative investigations using scatteroscope SCAT-4 are performed. The repeatability and measurement range for built at IOEangle scatterometer is estimated.

9

Are Deschampsia caespitosa (L.) Beauv. tussocks safe for seedling recruitment in the succession of wet meadows?

Kostrakiewicz-Gierałt K.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

707--721

EN

In stressful and harsh environments, safe sites for seedling recruitment may be created by nurse plants, which accumulate propagules and subsequently facilitate the establishment of individuals. The main goal of the presented studies focused on observations of seedling recruitment in small and large tussocks of Deschampsia caespitosa derived from patches of unmanaged Molinietum caeruleae meadows situated along the successional gradient and dominated by small meadow species (Patch I), by macroforbs (Patch II), or overgrown by trees and shrubs (Patch III). The studies showed that, irrespective of patch character, Serratula tinctoria, Selinum carvifolia, Lysimachia vulgaris and Filipendula ulmaria are among the best colonizers of Deschampsia caespitosa tussocks. The gradual decrease in number of species and offspring abundance along the successional gradient may be connected with a prolonged period of water stagnation accelerating the development of fungal pathogens, a major cause of mortality for buried diaspores. The growing frequency of species present in standing vegetation and the gradually rising contribution of swamp and forest taxa in consecutive patches may be due to the production of non-persistent diaspores by early successional species, as well as reduced seed immigration from neighboring sites. The obtained results included evidence that, regardless of patch character, the percentage of seedlings representing species present in and absent from existing vegetation as well as taxa with various vegetation types is similar in small and large tussocks. Furthermore, in small tussocks, regardless of patch character, anemochorous and hydrochorous taxa dominated, the frequency of endo- and epizoochorous taxa was much lower, while the percentage of species characterized by other modes of diaspore dispersal attained the lowest rates. In large tussocks, anemochorous and epizoochorous species prevailed, the share of endozoochorous and hydrochorous taxa was lower, and the contribution of species characterized by other modes of dissemination was very scarce. On the basis of these studies it might be concluded that, despite the successive decrease of species and seedling abundance, and along with the increase in the recruitment of taxa resident in standing vegetation, especially woody species, the tussocks of Deschampsia caespitosa are reservoirs of meadow species even in advanced successional stages and may play a significant role in the process of long-term species turnover.

10

Plasticity in dynamics and hygrochastic persistence in Anastatica hierochuntica (Brassicaceae) populations under simulated rainfall treatments

Hegazy A. K., Kabiel H. F., Alatar A. A., Lovett-Doust J.

Polish Journal of Ecology

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2013

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Vol. 61, nr 3

493--504

EN

Anastatica hierochuntica is a monocarpic desert annual whose dry skeletons, enclosing mature fruits, often persist for a number of years. The aerial seed bank in these hygrochastic ‘resurrection plants’ therefore persists too. Life tables and fecundity schedules were constructed for A. hierochuntica populations raised under four water treatments, equivalent to 100, 200, 500 and 1000 mm rainfall. Seedling survivorship showed a Deevey type III curve for 100 mm, and a type II curve for 200 mm, while 500 and 1000 mm treatments produced Deevey type I curves. Fewer seeds germinated and seedling survivorship was lower in the low water treatments. The stage-specific mortality rate reached 0.75 under the 100 mm treatment in the seed germination stage, compared to 0.08 under the 1000 mm treatment. Increased water availability resulted in greater plant growth and reproductive output, in terms of both number of seeds per individual and reproductive value. In field studies, aerial seed banks of small plant size-classes (from 1 to 32 cm3) were depleted within 3-to-7 years. For the large size-classes, > 32 cm3, only a portion (79.7-44.4%) of the seeds produced were dispersed during the observational experiment (the rest remaining within the tumbleweed ball, available for subsequent germination). The projected seed bank life-time for populations raised under different water treatments increased more than fivefold (from 3 to 17 years) for the 100 mm compared to the 1000 mm rainfall treatments. Local persistence of populations was thus likely to be reduced by water stress. Populations of A. hierochuntica characterized by weak plant growth and a preponderance of small size-classes will be more vulnerable to extinction due to their low reproductive output and reduced aerial seed bank reserve.

11

Effect of chemical reaction and radiation on double diffusive flow of a viscous, dissipative fluid through porous medium in a rectangular cavity with heat sources

Raju T. L., Muralidhar P.

International Journal of Applied Mechanics and Engineering

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2013

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Vol. 18, no. 4

1115--1150

EN

In this paper, an attempt is made to discuss the combined influence of radiation and dissipation on the convective heat and mass transfer flow of a viscous fluid through a porous medium in a rectangular cavity using the Darcy model. Making use of the incompressibility, the governing non-linear coupled equations for the momentum, energy and diffusion are derived in terms of the non-dimensional stream function, temperature and concentration. The Galerkin finite element analysis with linear triangular elements is used to obtain the global stiffness matrices for the values of stream function, temperature and concentration. These coupled matrices are solved using an iterative procedure and expressions for the stream function, temperature and concentration are obtained as linear combinations of the shape functions. The behavior of temperature, concentration, the Nusselt number and Sherwood number is discussed computationally for different values of the governing parameters, such as the Rayleigh Number (Ra), heat source parameter (α), Eckert number (Ec), Schmidt Number (Sc), Soret parameter (S0), buoyancy ratio (N).

12

Object oriented distribution in MUTDOD

Koszela J., Karpiński M.

Studia Informatica

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2011

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Vol. 32, nr 3B

65-76

EN

The paper contains overall description of distribution in object-oriented database created at Military University of Technology. This paper describes overall information about possible distribution's architectures and the ones provided in MUTDOD. The article contains information about distributed data storing, data processing and architecture of synchronization and replication units. Details about solutions provided in MUTDOD are also presented.

PL

Artykuł zawiera ogólny opis architektury rozproszenia w obiektowej bazie danych MUTDOD, która jest tworzona w Wojskowej Akademii Technicznej. Artykuł opisuje możliwe rozwiązania architektoniczne wraz z rozwiązaniami przewidzianymi w MUTDOD. Artykuł zawiera informacje o modułach synchronizacji i replikacji oraz rozwiązaniach zastosowanych przy rozproszonym przechowywaniu i przetwarzaniu danych.

13

Problem rozproszenia zabudowy w krajobrazie wiejskim, na przykładzie gminy Ogrodzieniec

Cygankiewicz I.

Przestrzeń i Forma

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2011

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nr 15

323-334

PL

Głównym czynnikiem kształtującym architekturę krajobrazu stał się żywiołowy rozwój zabudowy nie zintegrowany z otoczeniem. Zaburzenia wiejskiego układu krajobrazowego powodują nie tylko elementarne jego części jak dom z zagrodą i zadrzewieniem, ale również tło w postaci pól uprawnych, łąk, lasów, sieci dróg.

EN

The impulsive building development, non being a part and parcel of surroundings become a main landscape-architecture-forming factor. The rural-landscape violation is not only caused by definite units e.g. house, plus form plus a forestation, but also due to the pattern of fields grass lands, timberlands and roads.

14

Seed dispersal by the Rook (Corvus frugilegus L.) in agricultural landscape - mechanisms and ecological importance

Czarnecka J., Kitowski I.

Polish Journal of Ecology

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2010

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Vol. 58, nr 3

511-523

EN

The study aimed to evaluate the role of the Rook Corvus frugilegus in the long-distance seed dispersal in agricultural landscape. According to the literature, Rooks feed in the distance 0.3-1 km from the breeding colonies and 10-40 km from winter communal roosts, and these can be also the potential seed dispersal distances. We concentrated on the dispersal of diaspores of ornitochorous species and weeds (called non-ornitochorous) taken probably incidentally during foraging for other edible plant material. The contents of 528 pellets was analysed, 304 were collected at six sites of breeding colonies located in five rural parks and in one park on the city outskirts, and 224 under three winter roosts in the cities. Seeds representing 45 taxa were found, the most important groups among them are: ornitochorous species (10 taxa), non-ornitochorous (27 taxa, mainly weeds and ruderal species) and cereals (4 species). The mean number of seeds varied between 221 and 442 seeds per 100 pellets in the case of breeding colonies, and between 102 and 347 for wintering roosts. Fruits of ornitochorous species are an important element of the diet of the Rook: Cerasus avium and Fragaria sp. during breeding season and Vitis sp., Sorbus aucuparia and Sambucus nigra during winter. Nonornitochorous species are present in pellets in lower numbers and frequencies than ornitochorous ones and they can be divided into two groups: those transported during breeding season (mainly Stellaria media) and those during winter (Setaria sp. and Echinochloa crus-galli). We estimated that the number of non-ornitochorous seeds transported by birds from the biggest observed winter roosts can exceed 400 thousands seeds per month. The value is much lower in the case of the biggest breeding colony: approximately 16 thousands of propagules. We also checked if species found in pellets can germinate in natural conditions under the studied colonies. Viable individuals of 15 nonornitochorous and of one ornitochorous species were found there, and it was observed that disturbances of soil surface promote germination of some analysed species. @eng

15

Demography of a common butterfly on humid grasslands : Argynnis aglaja (Lepidoptera: Nymphalidae) studied by mark-recapture

Zimmermann K., Konvicka M., Fric Z., Cihakova V.

Polish Journal of Ecology

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2009

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Vol. 57, nr 4

715-727

EN

Much of the research into the demography of butterflies conducted in Europe during the last few decades focused on rapidly declining or, on the other hand, expanding species, whereas species with stable trend tend to be neglected by researchers. Argynnis aglaja, a widely distributed inhabitant of semi-natural grasslands, represents a suitable model for studying patterns of landscape persistence of not-yet-threatened grassland insects. Using mark-recapture method conducted for one season on humid meadows in Western Bohemia, Czech Republic, we show that this large-bodied species is capable to form large and dense populations, reaching densities of over 250 individuals per hectare. The adults were relatively long-living, an average female longevity (11.8 d) was over twice as high as an average male longevity (4.6 d), with maxima being 22 (a male) and 30 (a female) days. The prolonged female lifespan is beneficial for a species that do not emerge with fully-matured eggs and oviposits singly over large areas. Modelling mobility, well-approximated by an inverse-power function, predicted that about one individual in a thousand would cross the distance of 1000 meters. We conclude that the satisfactory conservation status of A. aglaja stems from its capability to reach high local densities combined with a good dispersal power.

16

Integracja oraz indeksowanie rozproszonych zasobów danych w technologii "data grid"

Kuliberda K., Kowalski T. M., Wiślicki J., Adamus R., Meina M.

Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

|

2009

|

T. 13, z. 3/2

1563-1570

PL

Problemy integracji rozproszonych zasobów są obecnie jednym z podstawowych zagadnień w dziedzinie gromadzenia danych i uzyskiwania spójnej i wiarygodnej informacji - odpowiedź została zawarta w artykule. Autorzy opisują aspekty przezroczystej integracji rozproszonych danych do obiektowego gridu bazodanowego poprzez technologię p2p z uwzględnieniem niezwykle istotnej kwestii ich indeksowania. Przedstawione rozwiązanie zostało zaimplementowane i zweryfikowane poprzez w pełni funkcjonalny prototyp. Tekst prezentuje podstawy wykorzystania architektury p2p oraz procedury indeksowania danych pochodzących z odległych źródeł, dzięki którym dostęp do nich staje się szybszy o rzędy wielkości, a transport przez sieć ograniczony do niezbędnego minimum.

EN

The problems of integration of distributed resources are currently one of the most substantial issues in the domain of collecting data and retrieving consistent and reliable information - the answer has been included in the following paper. Authors describe aspects of transparent integration of distributed data into an object-oriented data grid with application of the p2p technology and introducing extremely crucial issues of indexing. The presented solution has been implemented and verified in the completely functional prototype. The paper presents basics of application of the p2p architecture and procedures of indexing data originating from remote sources. These procedures accelerate data access by orders of magnitude and data transportation becomes limited to the necessary minimum.

17

Struktura rozproszona

Grodzicki P.

Czasopismo Techniczne. Architektura

|

2008

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R. 105, z. 2-A

217-224

PL

Geometryczna analogia zależności powierzchni wymiany i objętości-masy oraz przepływy energetyczne są dla przebiegu miejskich procesów i samej struktury miasta fundamentalne. Powierzchnie wymiany i przemiany energii pojawiają się we wszystkich miejscach, okolicznościach i zjawiskach, które uznajemy za decydujące i podstawowe dla zdrowego organizmu miasta. Przestrzenie publiczne, miejsca tętniące życiem, miejskie atraktory, wszystko to, co można nazwać "sercem miasta", rośnie na powierzchniach wymiany, miejscach przepływu energii, miejscach styku. Tworzą się na nich i jednocześnie generują nowe powierzchnie.

EN

Geometrical analogy of the surface of exchange and its relation to volume-mass, as well as energetic flows are fundamental to the course of urban processes and to the city structure itself. The energy exchange and transformation surfaces appear in all places, circumstances, and phenomena, which we consider decisive and basic to the healthy organism of the city. Public areas, places vibrant with life, urban attractors, everything that can be called "the heart of the city", appear on the exchange surfaces, places where energy flows, places of contact. They appear on them and simultaneously create new surfaces.

18

Collembola (Insecta) disperse the arbuscular mycorrhizal fungi in soil: pot experiment

Seres A., Bakonyi G., Posta K.

Polish Journal of Ecology

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2007

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Vol. 55, nr 2

395-399

EN

Collembola often play an important controlling role in the interrelationship between arbuscular mycorrhizal fungi (AMF) and host plants. However there are little data to prove AMF dispersing ability of Collembola. In our experiment Folsomia candida (Willem) did not consume the spores of Glomus mossea (Nicol. and Gerd.) and G. intraradices )Schenck and Smith), but Sinella coeca (Schott) consumed 45% of the G. mossea spores and 71% of G. intraradices spores. Both species were able to disperse mycorrhiza in the soil, but the efficiency of dispersal was different. F. candida carried the infection more effectively than S. coeca, in spite of the fact that F. candida did not consume the spores in the food choice experiment. The total plant biomass was 23% higher in the presence of F. candida and 8.5% higher in the presence of S. coeca then in the control treatment without Collembola. The water content of the plants was also a little higher in the presence of both Collembola species (about 10%) than that of the control plants, but this difference was not statistically significant. Collembola improved the dispersion of the AM fungi, therefore enhanced the nutrient and water uptake of the plant.

19

Dissipation and coupled fields

Kotowski R.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Mechanika

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2004

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Z. 81

71-101

EN

The evolution criterion and the variational formulation of the coupled phenomena in the materials with the inner structure are presented. The evolution criterion, as formulated by Glansdorff and Prigogine, allows to find the kinetic potential descrobing a dissipative process. This paper deals with the construction of the kinetic potential for micropolar media embedded in the dielectric fluid and subjected to the coupled field interactions. Generalization deals with the dissipative mechanical, thermal,and electromagnetic processes occurring in the micropolar medium. The formulated criterion is aplied to obtain the equilibrium conditions for micropolar elastic solids, micropolar electromagnetic fluids, and liquid crystals.The variational principle is constructed for micropolar media in external fields of forces on the example of liguid crystals subjected to the influence of thermal and electromagnetic fields. The problem of the dissipative processes produced in liquid crystals by the exernal end internal fields is considered.

20

Studies on species dispersion in microchannels

Ślusarczyk K.

Mikroelektronika i Informatyka : prace naukowe

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2004

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Z. nr 4

179-188

EN

Lab-on-a-Chip devices begin to play more significant role in everyday life. The variety of implementations influences on devices' dimensions reduction. The side-effect of miniaturization is the necessity of microchannels bending, what is the major source of samples' dispersion during electrokinetic processes. Studies on this phenomenon allow for developing methods which will shorten drastically the Lab-on-a-Chip design path and also to reduce the dispersion itself in microchannels. Results obtained during simulations of basic microchannels structures are presented in this paper.

PL

Systemy MEMS (Micro-Electro-Mechanical Structures) odgrywają coraz bardziej znaczącą rolę we współczesnym świecie, różnorodność ich zastosowań sprawia, że można je spotkać we wszytkich dziedzinach życia, począwszy od czujników przyspieszenia w samochodach, poprzez żyroskopy w rakietach i samolotach, dyszach drukarek, a skończywszy na przenośnych laboratoriach biologiczno-chemicznych. Jednym z przykładowych urządzeń do zastosowań biologiczno-chemicznych jest tzw. Lab-on-a-Chip będący rodzajem przenośnego laboratorium, integrującego w sobie zarówno przetwarzającą sygnały część elektroniczną jak i zestaw kanałów doprowadzających ciecze bądź gazy do odpowienich komór celem ich analizy, syntezy związków, mieszania, detekcji, etc.