Роль фахових кафедр в організації науково-дослідної діяльності студентів вищих навчальних закладів мистецького спрямування

У статті порушуються питання організації та надання консультативної допомоги щодо виконання кваліфікаційних робіт студентами і магістрантами вищих навчальних закладів мистецького спрямування. Пріоритет надається індивідуальній роботі наукового керівника зі студентом щодо змісту кваліфікаційної роботи, вибору методів і методик, запровадженню організаційно-педагогічних умов спрямованих на підвищення ефективності наукового дослідження

On Frequency-Domain Implementation of Digital FIR Filters Using Overlap-Add and Overlap-Save Techniques

In this paper, new insights in frequency-domain implementations of digital finite-length impulse response filtering (linear convolution) using overlap-add and overlap-save techniques are provided. It is shown that, in practical finite-wordlength implementations, the overall system corresponds to a time-varying system that can be represented in essentially two different ways. One way is to represent the system with a distortion function and aliasing functions, which in this paper is derived from multirate filter bank representations. The other way is to use a periodically time-varying impulse-response representation or, equivalently, a set of time-invariant impulse responses and the corresponding frequency responses. The paper provides systematic derivations and analyses of these representations along with filter impulse response properties and design examples. The representations are particularly useful when analyzing the effect of coefficient quantizations as well as the use of shorter DFT lengths than theoretically required. A comprehensive computational-complexity analysis is also provided, and accurate formulas for estimating the optimal DFT lengths for given filter lengths are derived. Using optimal DFT lengths, it is shown that the frequency-domain implementations have lower computational complexities (multiplication rates) than the corresponding time-domain implementations for filter lengths that are shorter than those reported earlier in the literature. In particular, for general (unsymmetric) filters, the frequency-domain implementations are shown to be more efficient for all filter lengths. This opens up for new considerations when comparing complexities of different filter implementations.Comment: 13 pages, 26 figure

Integer Linear Programming Modeling of Addition Sequences With Additional Constraints for Evaluation of Power Terms

In this work, an integer linear programming (ILP) based model is proposed for the computation of a minimal cost addition sequence for a given set of integers. Since exponents are additive under multiplication, the minimal length addition sequence will provide an economical solution for the evaluation of a requested set of power terms. This is turn, finds application in, e.g., window-based exponentiation for cryptography and polynomial evaluation. Not only is an optimal model proposed, the model is extended to consider different costs for multipliers and squarers as well as controlling the depth of the resulting addition sequence.Comment: This manuscript was written in 2012, and, hence, lacks more recent reference

Stochastic Analysis of LMS Algorithm with Delayed Block Coefficient Adaptation

In high sample-rate applications of the least-mean-square (LMS) adaptive filtering algorithm, pipelining or/and block processing is required. In this paper, a stochastic analysis of the delayed block LMS algorithm is presented. As opposed to earlier work, pipelining and block processing are jointly considered and extensively examined. Different analyses for the steady and transient states to estimate the step-size bound, adaptation accuracy and adaptation speed based on the recursive relation of delayed block excess mean square error (MSE) are presented. The effect of different amounts of pipelining delays and block sizes on the adaptation accuracy and speed of the adaptive filter with different filter taps and speed-ups are studied. It is concluded that for a constant speed-up, a large delay and small block size lead to a slower convergence rate compared to a small delay and large block size with almost the same steady-state MSE. Monte Carlo simulations indicate a fairly good agreement with the proposed estimates for Gaussian inputs.Comment: 13 pages, 8 figure

Особливості вживання часових форм у текстах художнього стилю (на матеріалі німецької мови)

(UA) У статті розглядається вживання часових форм дієслова як стилістичних засобів; розкриваються особливості реалізації та функціонування категорії часу з точки зору лінгвістики тексту.(EN) The article views the usage of the tense forms of the verb as stylistic devices in belles-lettres texts; it highlights the peculiarities of realization and functioning of the category “Time” from the point of view of linguistics of the text

Effect of the amount of gravel and overturning on the rutting on gravel roads

Nybyggnation och underhåll av skogsbilvägar medför stora kostnader för skogsbruket. Georadar (GPR) är en teknik som kan användas för att läsa av en vägs struktur vilket ger ett möjligt tillvägagångssätt för att reducera kostnader vid upprustning av vägar. Detta genom att endast partier med sämre bärighet rustas upp och därmed läggs rätt mängd material på rätt ställe längs vägen. Alternativet är dagens subjektiva bedömning av åtgärdsbehov och godtycklig placering av grusmängd. Syftet med denna studie var att kvantifiera skillnader i spårbildning mellan 100 %, 75 % samt 50 % påförd materialmängd i överbyggnaden av total rekommenderad materialmängd för att uppnå bärighet motsvarande vägklass 3B, samt hur spårbildning i vägkroppen påverkas av vältning. Grusmängden för överbyggnaden dimensionerades med ledning från data insamlade med GPR och fallviktsmätare. Analysen grundade sig på inventering av sex block med vardera tre sträckor (50 meter långa) samt en referenssträcka (30 meter lång), för vilka materielmängd samt behandling skiljde sig åt. Vägytan mättes dagligen inom blocken under en fem-dagarsperiod då vägen belastades av virkestransporter. Den skogsbilväg studien genomfördes på hade en undergrund av normalmorän. Ingen signifikant skillnad mellan vältade eller ovältade sträckor uppvisades. Inga signifikanta skillnader uppvisades heller mellan sträckorna med olika materialnivåer. Det maximala spårdjupet som registrerades uppgick till 87 mm, medelvärdet för spårbildningen var 23 mm. Dessa resultat tyder på att den materialmängd som påförs överbyggnaden vid upprustning av en väg kan reduceras, om vägen har en undergrund av normalmorän, utan att spårbildning vid trafikering blir besvärande vid förhållanden liknande de för denna studie. Detta innebär en stor teoretisk besparingspotential för SCA Skog, då den rådande rekommendationen för materialmängd för att uppnå B-bärighet är 1630 ton/km, vilket innebär en materialkostnad om ca 100 000 kr/km. Ytterligare studier krävs för att fastställa möjligheterna till och nivåerna för en materialreducering, då denna studie inte uppvisat besvärande spårbildning behövs studier med lägre materialmängder.Construction and maintenance of forest roads are costly for the forest industry. Ground Penetrating Radar (GPR) is a technique for reading the road structure, which is a possible approach to reduce the cost of road upgrades. This by simply placing gravel on stretches with lower bearing capacity, and thereby adding the right amount of material in the right place along the way. The alternative is today's subjective assessment of the need for action and arbitrary placement of gravel lot. The purpose of this study was to quantify differences in rutting between 100 %, 75 % and 50 % applied gravel amount on the superstructure. These amounts were based on the total recommended amount of material to achieve buoyancy corresponding to road bearing class 3B, and how rutting in the road structure is affected by overturning. Gravel amount for the superstructure was designed with guidance from the data collected with the GPR and a falling weight deflect meter. The analysis was based on the inventory of six blocks, each with three sections (50 meters long) and a reference section (30 meters long), where the road surface was measured daily for five days of timber load transport. The study was conducted on a subgrade of normal moraine No significant difference between overturned or not overturned distances where exhibited. Neither was significant differences demonstrated between sections with different material amounts. The maximum rut depth recorded was 87 mm; the mean of rutting was 23 mm. These results suggest that the amount of material applied to the superstructure at the improvement of a road can be reduced if the road has a subgrade of normal moraine, rutting was not troublesome for traffic on any section. This is a significant theoretical savings potential for SCA Skog, since the current recommendation for the amount of material to achieve the B-bearing capacity is 1630 tons / km, which means a material cost of approximately 100.000 SEK / km. Further studies are required to determine the possibilities and levels of a material reduction, since this study haven’t shown troubling degrees of rutting studies with lower material amounts are required