Stock prices are dynamic and changing frequently whenever the financial markets are opened. Many people aspire to know where prices are likely to be at future times. One of the basic problems, connected with stock valuation is to create an appropriate model of stock prices dynamics. This paper deals with the stock valuation models, such as binomial, additive, multiplicative, Brownian motion and etc. These models appeals to hypothesis, declaring that returns of stock follows by normal distribution and stock prices by lognormal one. The aim of this work is to test these hypothesis. The research of this paper discloses the basic tendency, announcing that stock is not applicable for a real adaptability of methods in Lithuanian companies because the returns of stock do not follow by the normal distribution. Disputed situation is opposite in companies of the USA. The returns of stocks are calculated by the following ways. They are numbered in the area of MS Excel. In order to review the conditions of normality, the SAS software was chosen. Finally, Delphi 10 programming language was selected for realization of the binomial tree.

This paper concentrates on valuation of interest rate. Changes in the short rate captured in a stochastic model which generates a term structure of interest rates. Leading interest rate models are Vasicek model, Cox, Ingersoll & Ross model and Heath, Jarrow and Morton model. First two model are called mean reversion of the short rate, that is, a tendency for the short rate to drift back to some underlying rate. Both models assume that the process for the short rate r is stochastic with one source of uncertainty. The two models differ in the handling of volatility. The last one model describes the forward rate evolution. The dynamics of interest rate of Lithuania has changed apace in these latter years. This can be explained by spontaneous process of resurgent economics. Because Vasicek and Cox, Ingersoll & Ross models are similar in essence, dynamics of interest rate is also similar according to these models. The received results using separate algorithms fit laws of fluctuation in interest rates of Republic of Lithuania. Problem is realized with programme equipment Microsoft Visual Basic 6.3.

Mūsų klimato sąlygomis topinambai gerai auga, tačiau mažai žinoma, koks auginimo būdas yra tinkamiausias, kad pasiektume kuo didesnį derlių. Šio darbo tikslas buvo išanalizuoti, kuris žemės dirbimo būdas yra tinkamiausias auginti topinambus, kad pasiektume kuo didesnį derlių ir galėtume atlikti topinambų auginimo dinamikos tyrimus. Atlikus tyrimus nustatyta, kad topinambams nereikia daug priežiūros, jie labai gerai auga net ir netręšti. Nustatėme, kad iš pirmųjų metų laukelyje kuris buvo vieną kartą kauptas derlius buvo didžiausias , gumbų - 29,8 t/ha, antžeminės dalies - 15,9 t/ha. Taip pat nustatytas drėgmės kiekis topinambuose, sausosios medžiagos, cheminė sudėtis, apskaičiuotas galimas etanolio kiekis ir jo šilumingumas . Nustatyta, kad dvejus metus nenukasti topinambų neapsimoka. / Climate conditions in our Jerusalem artichokes grow well, but little is known, what is the most appropriate way of cultivation in order to achieve maximum yield. This work was to analyze which tillage is the best way to grow Jerusalem artichokes, in order to achieve maximum yield and can make artichoke growing dynamics research. Studies show that Jerusalem artichokes do not need a lot of care, they are very well grow even fertilization. We found that the first year of the field that was once wasted but yields were highest tuber - 29.8 t / ha of ground - 15.9 t / ha. Also, the moisture content of Jerusalem artichoke, the dry matter, chemical composition, calculated the potential of ethanol and its calorific value. It was found that two years thou diggedst Jerusalem artichoke is not profitable.

The dissertation is dedicated to the detailed numerical modelling of generation dynamics of actively and/or passively Q-switched diode laser longitudinally pumped solid-state lasers, characterization of spatial and temporal laser properties and for the demonstration of application possibility of created minilasers. A detailed theoretical model for the description of generation dynamics using travelling wave approach is presented. In this model more parameters of active laser medium, pump sources and resonator architecture are taken into account. In this thesis the results which show the principal difference between results obtained using the laser travelling wave model and point laser model are presented. Using point laser model the problems of generated pulse timing jitter in passively Q-switched lasers are described and its lowering possibilities using different pumping methods are suggested. In this thesis new, based by the second order moment, laser beam characterisation by knife-edge method is presented. Also laser pulse compression possibilities in tetrachloride CCL4 medium are described. It is showed that using seed signal it is possible to obtain shorter (< 60 ps) and more stable optical pulses. In this thesis application possibilities of created minilasers are presented: the experimental results of the Z-scan measurements obtained using pulses with different pulse shapes for fused silica are presented; also experiments, in which, created minilasers for paper cleaning... [to full text] / Disertacija skirta diodais kaupinamų kietojo kūno lazerių su aktyviąja ir pasyviąja kokybės moduliacija generacijos dinamikos detalesnei skaitmeninei analizei, lazerio impulsų laikinių ir erdvinių parametrų charakterizavimui ir sukurtų minilazerių panaudojimo galimybių demonstracijai. Generacijos dinamikos detalesniai skaitmeniniai analizei, darbe pristatomas sukurtas bėgančiųjų bangų modelis, kuriame atsižvelgiama ne tik į daugelį procesų vykstančių lazerio aktyviajame elemente, bet ir į rezonatoriaus konfigūraciją bei kaupinimo šaltino parametrus. Pateikiami skaitinio modeliavimo rezultatai demonstruojantys šio modelio privalumus lyginant su dažniausiai naudojamu taškiniu lazerio modeliu. Naudojant taškinį lazerio modelį yra nagrinėjama generuojamų impulsų laikinio tirtėjimo problema pasyvios kokybės moduliacijos lazeriuose ir pasiūlyti mažinimo būdai naudojant skirtingus kaupinimo būdus. Darbe taip pat pateiktas naujas, antraisiais momentais pagrįstas, pluošto charakterizavimo judančiu peiliu metodas. Nagrinėjamos lazerių impulsų spūdos galimybės tetrachlorido CCL4 skystyje ir pademonstruota, kad naudojant užkrato signalą galima gauti trumpesnius (< 60 ps) ir stabilesnius optinius impulsus. Darbe pademonstruotos sukurtų minilazerių pritaikymo galimybės: aprašomas netiesinio lūžio rodiklio kvarciniame stikle matavimas Z-skenavimo metodu ir gautų duomenų apdorojimo procedūra įskaitant naudojamų impulsų erdvinę ir laikinę formą; aprašomi eksperimentai, kuriuose sukurti... [toliau žr. visą tekstą]