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Analiza, modelowanie oraz prognozowanie stanu i rozwoju kryzysowej sytuacji socjalno-politycznej : pewne rozważania wstępne

Kurbanowicz-Ramazanow S., Stemplewska L.

Studia i Materiały / Europejska Uczelnia Informatyczno-Ekonomiczna w Warszawie

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2014

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Nr 2(8)

77--100

PL

W pracy po raz pierwszy przedstawiono pewne rozważania wstępne dotyczące analizy i modelowania stanu socjalno-politycznego głębokiego kryzysu na podstawie supersystemu typu „Majdan”. Pokazano możliwość stosowania podejścia entropii i zaprezentowano jedno ogólne podejście budowy integralnego nieliniowego dynamicznego modelu interakcji w złożonym systemie o wielu agentach typu „Majdan” na podstawie równania logistycznego oraz jego szczególne przykłady.

EN

This paper presents some preliminary considerations on the analysis and modeling of socio-political state of deep crisis based on “Maidan” supersystem. The possibility of using entropy approach is shown and a general approach of building an integral nonlinear dynamic model of interaction in a complex system with multiple agents of “Maidan” type based on the logistic equation is presented as well as its specific examples.

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Stratigraphy and sedimentology of the Niger Delta

Reijers T. J. A.

Geologos

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2011

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Vol. 17, No. 3

133--162

EN

During the Cenozoic, until the Middle Miocene, the Niger Delta grew through pulses of sedimentation over an oceanward-dipping continental basement into the Gulf of Guinea; thereafter progradation took place over a landward-dipping oceanic basement. A 12,000 m thick succession of overall regressive, of flapping sediments resulted that is composed of three diachronous siliciclastic units: the deep-marine pro-delta Akata Group, the shallow-marine delta-front Agbada Group and the continental, delta-top Benin Group. Regionally, sediment dispersal was controlled by marine transgressive/regressive cycles related to eustatic sea-level changes with varying duration. Differential subsidence locally influenced sediment accumulation. Collectively, these controls resulted in eleven chronostratigraphically confined delta-wide megasequences with considerable internal lithological variation. The various sea-level cycles were in or out of phase with each other and with local subsidence, and interfered with each other and thus influenced the depositional processes. At the high inflection points of the long-term eustatic sea-level curve, floodings took place that resulted in delta-wide shale markers. At the low inflection points, erosional channels were formed that are often associated, downdip, with turbidites in low-stand sediments (LSTs). The megasequences contain regional transgressive claystone units (TST) followed by a range of heterogeneous fine-to-coarse progradational or aggradational siliciclastic (para)sequence sets formed during sea-level high-stand (HST). An updated biostratigraphic scheme for the Niger Delta is presented. It also updates a sedimentation model that takes into consideration local and delta-wide effects of sea-level cyclicity and delta tectonics. Megasequences were formed over time intervals of ~5 Ma within individual accurate megastructures that laterally linked into depobelts. The megasequences form the time-stratigraphic frame of the delta and are the backbone for the new delta-wide lithostratigraphy proposed here. Such a new lithostratigraphy is badly needed, in particular because of the vigorous new activity in the offshore part of the Niger Delta (not covered in this contribution). There, as well as in the onshore part of the delta, the traditional lithostratigraphic subdivision of the Cenozoic Niger Delta section into three formations is insufficient for optimum stratigraphic application; moreover, the various informal subdivisions that have been proposed over time are inconsistent.

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Efekt umocnienia drewna buka w warunkach wolnozmiennych cyklicznych obciążeń

Czachor G.

Inżynieria Rolnicza

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2002

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R. 6, nr 5, cz. 1

261--269

PL

Analizowano efekt zmian wartości cech mechanicznych drewna buka jako skutek realizacji testu histerezy odkształceń. Zmianę wartości wytrzymałości na ściskanie σc, granicy sprężystości σspr, oraz modułu sprężystości Ec, w przedziale wilgotności w od O do 100% opisano ogólną formułą matematyczną: y = a + b*exp(-c*w). Przyrost wartości σspr, σc oraz Ec, wyznaczono dla testu 10 i 60 cyklowego. Stwierdzono, że wolnozmienne cykliczne obciążenia powodują wzrost wartości granicy sprężystości σspr, i modułu sprężystości Ec, zaś wartość naprężeń niszczących σc nie ulega zmianie.

EN

The influence of hysteresis on some changes in mechanical properties of beech wood was analyzed. The tension strength σc values, elastic σspr limit and elastic modulus Ec, of 0-100% moisture were characterized by mathematic formula: y = a + b*exp (-c*w). An increase in σspr, σc and Ec values in 10 and 60 hysteresis loops was determined. It was found that cyclic bad increased elastic σspr limit and elastic Ec, modulus, however tension strength σc values remained unhanged.