Cells of a prototype powered wheelchair can be designed in various connections to provide different supply voltages which has impact on the efficiency of other wheelchair drive elements. The impact of cell configuration and resulting battery voltage on overall efficiency of power elements have been studied to determine the optimal configuration and voltage of the pack. A brief description of a battery energy storage system was given, and main requirements and variables were introduced to reveal the flexibility of the battery design. The efficiency versus supply voltage plots of a drive converter and battery charger were presented and discussed to find the optimal battery voltage. The motor design was analyzed from the fill factor perspective. The calculated efficiency parameters of all drive power elements were used to discuss and select an optimal battery cell configuration.

During summer seasons of 1982 and 198S the authors collected observations on rate of soil thawing under and around shallow tundra lakes. Two lakes were studied: A on the terrace 10 m a.s.1. in northern Kafliöyra whereas B at about 40 m a.sJ. in southern margin of Sarsdyra. The lakes indicated considerable variation of water lavels (10—20 m) caused by limited water bodies (to 40—80%) at the end of the observation period. Soil thawing was studied in sections across lake basins and to 20 m around them. A thawing rate was found greater under the lakes than in their surroundings and it was noted to be in the same time the quicker the larger was the lake. Studies of the lake B proved also that increase in the reservoir depth made a greater rate and depth of summer thawing. This process varied also considerably in time. At the beginning of a polar summer the dry soil of elevated tundra thaws sooner while permafrost under water reservoirs gets conserved. Later on (in August) a quick aggradation of active layer in noted under the lake. A heat accumulated in water bodies prolongs the soil thawing as well.

Storia della spiritualit cristiana sotto il aspetto metodologico

Sommario

L’oggetto della storia della spiritualit lo studio dell’esperienza dell’uomo nella sua relazione con Dio come Essere Assoluto, che si attua e sviluppa nel corso dei tempi. la trascendenza a permettere allo spirito umano di mettersi in contatto con l’Assoluto e in tale caso si pu parlare della storia di spiritualit giudaica, musulmana, buddista, induista e ovviamente cristiana. La storia della spiritualit come disciplina scientifica nata agli inizi del XX secolo, la sua importanza incresciuta grazie allo sviluppo delle scienze storiche soprattutto della storia della Chiesa e della teologia. Il suo constante sviluppo attestano molte ricerche scientifiche, periodici, specialistiche edizioni enciclopediche, dizionari. La storia della spiritualit cristiana analizza e cerca di dare la spiegazione della relazione che l’uomo sperimenta nel suo contatto con Dio Uno e Trino, che si rivelato pienamente in Ges Cristo. Essendo di sua natura una disciplina scientifica interdisciplinare usa metodi adatti per arrivare alla verit. La costatazione, la descrizione e l’interpretazione dei fatti, di cui si occupa la storia della spiritualit, ha un valore enorme per la cultura umana.

This paper is dedicated to Voivodship Park of Culture and Recreation in Chorzów (Silesia Park) – one of the biggest of its kind in Poland and in Europe (ca. 600 ha of total area). Construction of the Park had begun in 1954 according to the design under the direction of prof. Władysław Niemirski. After many years it became an example of successful land remediation and re-naturalization of anthropogenic landscape. The whole facility though formally created in socrealism style, actually represents classical modernism’s features inspired probably by American parks with a rich recreation program.