An improved theoretical formulation is proposed here to predict the moment field induced in laterally loaded RC rectangular stiffened plates including the effect of strength and stiffness of the internal stiffening beams. Design charts are also presented for their quick proportioning. The study reveals the effect of strength and stiffness of the internal beams on the moment field induced in the plate-system which was not considered, currently, by various methods prescribed by different design codes. The use of stiffened-plates becomes mandatory in buildings to accomodate some architectural constraints as well as for satisfying the serviceability criterion of design codes. This type of a structural system is efficient, economical and readily constructible in most of common materials. Moreover, it can be built as a monolithic unit or as a composite system comprising a plate cast in concrete and beams constructed in prestressed concrete, fabricated sections in steel, and so forth. A working example is presented to demonstrate the validity and efficiency of the simplified approach in comparison to finite element based design and other code prescribed methods. and Obsahuje seznam literatury a Appendix A
This paper presents closed form solution for unsteady flow equation corresponding to the transient hydraulic head, flow rate and volumetric exchange of a confined aquifer which is in contact with a constant piezometric head at one end and a stream whose water level is rising at a constant rate at the other end. The aquifer is also subjected to receive constant inflow due to rain infiltration. The unsteady groundwater flow equation is solved using Laplace transform to get analytical expressions for the transient hydraulic head and flow rate at the left and right interfaces and the net volumetric exchange of water at the aquifer-stream interface. The analytical results presented here show the effect of recharge due to rain infiltration on the net volumetric exchange and reveal the conditions for which net inflow in the aquifer could be positive, negative or zero. The results obtained have the capability to determine transient hydraulic head for two extreme scenarios: (i) very slow rise and (ii) very fast rise in the stream water. Analytical result show that the net volumetric exchange could be positive, zero or negative depending on the surface infiltration and stream water rise rate. and Príspevok obsahuje analytické riešenie rovnice neustáleného prúdenia vzhľadom na neustálenú hydraulickú výšku, rýchlosť prúdenia a objemové toky vo zvodnenom kolektore s napätou hladinou, ktorý je v kontakte s konštantnou piezometrickou výškou na jednej strane a s tokom s konštantne sa zvyšujúcou hladinou vody na strane druhej. Zvodnený kolektor je tiež napájaný konštantnou rýchlosťou infiltrovanou vodou zo zrážok. Rovnica neustáleného prúdenia podzemnej vody je riešená s použitím Laplaceovej transformácie, aby sme získali neustálenú tlakovú výšku na ľavej aj pravej strane a objemový prítok vody na rozhraní zvodnený kolektor - tok. Výsledky analytického riešenia, ktoré predkladáme, ukazujú vplyv infiltrácie zrážok na doplňovanie podzemnej vody a odhaľujú podmienky, za ktorých prítok do zvodneného kolektora môže byť kladný, negatívny, alebo nulový. Získané výsledky umožňujú určiť neustálené hydraulické výšky pre dva extrémne scenáre: (i) veľmi pomalé a (ii) veľmi rýchle zvýšenie hladiny vody v toku. Analytické riešenie ukazuje, že objem vody, ktorou je zvodnený kolektor doplňovaný, môže byť kladný, záporný, alebo nulový, v závislosti na intenzite infiltrácie a rýchlosti zvyšovania sa hladiny vody v toku.
The paper deals with a new manner of obtaining a closed-form analytical solution of the problem of bending of a beam on an elastic foundation. The basic equations are obtained by a variational formulation based on the minimum of the total potential energy functional. The basic methods for solving the governing equations are considered and their advantages and disadvantages are analyzed. The author proposes a felicitous approach for solving the equilibrium equation and applying the boundary conditions by transformation of the loading using singularity functions. This approach, combined with the resources of the modern computational algebra systems, allows a reliable and effective analysis of beams on an elastic foundation. The numerical examples show the applicability and efficiency of the approach for the solution of classical problems of soil-structure interaction. and Obsahuje seznam literatury
An analytical solution for the two-dimensional tension leg platform (TLP) interacting with ocean wave is presented. The legs of TLP are considered as elastic springs. The flow is assumed to be irrotational and single-valued velocity potentials are defined. The effects of radiation and scattering are considered in the boundary value problem. Because of linear behavior of legs during wave excitation, ignoring coupling effects with other degrees of freedom, the analytical solution of heave response has good agreement with the real behavior of the structure. and Práce uvádí analytické řešení působení vln na dvoudimenzionální pevně ukotvenou plošinu (TLP). Úchyty plošiny jsou uvažovány jako elastické pružiny. Předpokládá se nevírový tok a je definováno jednoznačné rychlostní pole. Okrajové podmínky zahrnují vlivy radiace a rozptylu. Předpoklad lineárního chování úchytů při excitaci mořskými vlnami i zanedbání některých dalších efektů v analytickém řešení odezvy TLP na vznášení ukázaly, že existuje soulad mezi naším řešením a skutečným chováním konstrukce.
The article presents an analytical solution to deterministic problems of infinite fatigue life (determining the safety factor, predicting tha carrying capacity and proposing the cross-section dimensions) of machine parts subjected to arbitrary pure harmonic loading. Presented mathematical models do not require to construct any fatigue strength diagram adopting it only as a basis of graphical solving. Finally, these models may serve as a starring point formulating analytical solution to deterministic problems of infinite fatigue life of machine parts under combined harmonic loading. and Obsahuje seznam literatury
A new analytical formula of the velocity profile for both the laminar and turbulent flow in a tube with a circular cross-section will be introduced in his article. This formula is rather simple and easy to use. The advantage of this velocity profile is that one formula can be used for laminar and turbulent flow. This new formula will be compared with power law velocity profile and with the law of the wall also called as the log-law. and Obsahuje seznam názvosloví
Cílem Rortyho článku „Analytická a konverzační filosofie“ je nahrazení distinkce mezi analytickou a kontinentální filosofií rozlišením mezi filosofií analytickou a filosofií konverzační. Tím dojde při nahlížení rozdílu mezi oběma typy filosofie k odstranění geografického hlediska, které, ač samo o sobě poskytuje určitou možnost rozlišit jednotlivé typy filosofů, není dle Rortyho ve skutečnosti určující. Tento rozdíl spočívá především v odlišném náhledu filosofie na sebe samotnou, na smysl a cíle své práce. Spočívá v odpovědi na otázku, zda filosofie může něco poznávat takové, jaké to doopravdy je, či nikoli a zda se může vydat po cestě vědy, či by měla naopak vnímat sebe sama spíše jako konverzaci a rozvíjení kulturního uvažování., The aim of Rorty’s article Analytic and conversational philosophy is to replace the distinction between analytic and continental philosophy with a distinction between analytic and conversational philosophy. This is achieved through a perception of the difference between the two types of philosophy that rejects the geographical viewpoint which, though it may provide a certain possibility of distinguishing the specific types of philosophy, is not in Rorty’s view really decisive. The difference consists above all in the distinctive view of philosophy of itself, and of the sense and aim of its endeavour. It consists in the response to the question of whether philosophy can or cannot know something as it really is; whether it can follow the path of science; or whether it should rather perceive itself as a conversation and an opening up of cultural reflection., and Richard Rorty.