Deformations of Gabor Frames

The quantum mechanical harmonic oscillator Hamiltonian generates a one-parameter unitary group W(\theta) in L^2(R) which rotates the time-frequency plane. In particular, W(\pi/2) is the Fourier transform. When W(\theta) is applied to any frame of Gabor wavelets, the result is another such frame with identical frame bounds. Thus each Gabor frame gives rise to a one-parameter family of frames, which we call a deformation of the original. For example, beginning with the usual tight frame F of Gabor wavelets generated by a compactly supported window g(t) and parameterized by a regular lattice in the time-frequency plane, one obtains a family of frames F_\theta generated by the non-compactly supported windows g_\theta=W(theta)g, parameterized by rotated versions of the original lattice. This gives a method for constructing tight frames of Gabor wavelets for which neither the window nor its Fourier transform have compact support. When \theta=\pi/2, we obtain the well-known Gabor frame generated by a window with compactly supported Fourier transform. The family F_\theta therefore interpolates these two familiar examples.Comment: 8 pages in Plain Te

Evaluation of information technology product in the company Chipolo

In today’s world information technology is becoming more and more present, as we find it in all the areas of the society. Companies that want their products or services to compete in the emerging markets of IT products or services, need high-quality IT solutions. Therefore, the evaluation and improvement of performance of information technology products is an important area for both individual companies and wider society. As part of this thesis, a model for evaluation of features of the information technology product was designed and presented. The model is designed on the basis of existing methodologies and tools used to evaluate the successful performance of products. The model was tested in one of Slovenian companies in the context of a case study, which showed that the use of a model for evaluation helped the company in improving their information technology product. Because the model proved to be successful it can be applied to other companies or other products in the future

The Protection of Karst Aquifers: the Example of the Bistrica Karst Spring (SW Slovenia)

Kraški izviri predstavljajo pomemben vir pitne vode tako v Sloveniji kot v svetu. Zaradi specifične zgradbe so kraški vodonosniki v večini zelo občutljivi na onesnaženje. Avtor na primeru kraškega izvira Bistrica izpostavi problematiko varovanja kraške podtalnice ter predstavi glavne pomanjkljivosti ter slabosti sedanje zakonodaje in uveljavljene prakse na področju varovanja kraških vodonosnikov v Sloveniji. Kljub relativno ugodnim razmeram za varovanje (redka poseljenost, manj intenzivno kmetijstvo,…) v primerjavi s kraškimi območji drugod po svetu je veliko pomembnih kraških izvirov slabo zavarovanih. Vodovarstveni režimi so največkrat slabo definirani, nadzor nad izvajanjem zaščitnih ukrepov pa neučinkovit.Karst springs are important drinking water sources both in Slovenia and elsewhere in the world. Due to their specific structure, karst aquifers are in most cases highly vulnerable to pollution. Through the example of the Bistrica karst spring, the author highlights the problems of karst groundwater protection and presents the main shortcomings and weaknesses of the relevant legislation in force and of established practices in the field of the protection of karst aquifers in Slovenia. Despite relatively favourable conditions for water protection (scarce population, less intensive agricultural activities etc.) as compared with karst areas elsewhere in the world, many important karst springs in Slovenia are improperly protected. Water protection regimes are often established inappropriately and control over the implementation of protective measures is inefficient

Hydrogeological study of the Malenščica karst spring (SW Slovenia) by means of a time series analysis

Time series analyses are often used for the investigation of karst aquifers, but are only rarely employed in a way of using a large number of spatially distributed time series. Furthermore, only a small number of applications employ other types of hydrologi­cal data apart from rainfall, water level and discharge. The pre­sented study of the Malenščica karst spring aquifer underlines the usefulness of the simultaneous auto- and cross-correlation analysis of daily and hourly hydrological data sets, including discharge, water level, temperature, electrical conductivity and rainfall on a regional scale. The results of the autocorre­lation analysis show that the storage capacity of the spring is moderate, but this does not indicate that the system, whichis characterized by prevailing conduit porosity, is less intensively karstified. This suggests that well-karstified systems of a more complex structure can have higher memory effects than less complex systems. The results of the cross-correlation analysis show that karst springs and watercourses in the investigated area react instantly and simultaneously to rather homogeneous precipitation, yet withdifferent intensity. In suchcases a cross-correlation analysis between rainfall or ponors as inputs and springs as outputs does not provide sufficient information on the hydrogeological functioning of the system, whereas the results of a cross-correlation analysis of electrical conductivity data sets provide valuable information on its functioning and can be easily compared to those obtained by tracer tests. On the other hand, the applicability of a temperature time series in suchcomplex karst systems is limited. A comparative analysis of the results of the time series analyses performed in succes­sive hydrological years has proven that the selection of the hy­drological year can have strong effects on the results of a time series analysis

Sediment production in flysch badlands: A case study from Slovenian Istria

This article deals with the results of seven years of measurements of sediment release from the flysch badlands in the Rokava River headwaters. Measurements of sediment production were carried out in erosion plots, and measurements of cliff (or rockwall) retreat using erosion pins. Selected meteorological time series from the Portorož Airport meteorological station were included in the analysis. The calculation showed that from 2008 to 2015 (149 measurements) sediment production was 36 kg/m² per year and the flysch cliff retreated by 146 mm or 21 mm per year. The amount of sediment produced is moderately positively correlated with the number of days between successive measurements (r = 0.51), with a recorded daily transition of air temperature over/below 0 °C (r = 0.56) and slightly more weakly correlated with the precipitation amount (r = 0.45). On the other hand, the amount of sediment produced has a low negative correlation with average air temperature (r = −0.29) and average minimum air temperature (r = −0.30). However, no statistically significant correlation was calculated between the amount of sediment produced and average wind speed

Званични прописи и лични доживљај звоњаве црквених звона

Through the analytical approach of studying official and perception-related discourse on bell ringing I accentuate the complexity of aspects that the sound of church bell presents in contemporary society. I point out the misleading officially defined level of noise nuisance and reveal how, when and why bell ringing is perceived as a positive or negative part of the acoustic environment. The study argues for a holistic approach to the noise nuisance issues, still much underestimated in the official discourse, that co-create our everyday soundscape.Званични прописи и лични доживљај звоњаве црквених звона (Сажетак) У Словенији, након Другог светског рата, убрзана индустријализација у градским и приградским срединама значајно је променила њихово звучање. Појавили су се многи нови звуци, неки су се изгубили или су гурнути у позадину, неки су изгубили своје значење, постали неважни или нежељени. Расправа коју овде презентујем на тему звоњаве црквених звона и њиховог положаја у савременом друштву инспирисала ме на ново промишљање о значењу звоњаве у простору и времену. Ако је звук црквених звона био један од централних звукова акустичног простора и људских живота у прединдустријском добу, ово се у потоњим деценијама значајно променило, посебно када је звук звона постао део дискурса о буци у јавном простору. Промена у доживљају звоњаве црквених звона првобитно је била резултат политичке контроле над звуком. Време за црквену звоњаву било је ограничено, контролисано, или у потпуности забрањено, а власти су путем прописа о реду и миру у јавном простору контролисале сонорност религијске провенијенције. Но, упркос званичним прописима, десакрализација простора била је најочигледнија у урбаним центрима и није у истој мери афектовала руралне средине. У доба социјализма, звоњава је била регулисана на државном нивоу, а жалбе на ниво јачине звука биле су веома ретке и нису биле јавно изражаване, док је у постсоцијалистичком раздобљу приметан пораст тензија, што се рефлектовало и у медијском дискурсу. Постепено је ниво буке проузрокован звоњавом постао значајан проблем. Могуће је пратити бројне дискусије на форумима, блоговима, коментарима испод новинских чланака, затим, такозване „мирне терористичке” акције усмерене ка утишавању звоњаве, окупљања по селима (и за и против звоњаве), пресуду Уставног Суда у корист црквене звоњаве, као и промене у законима који се односе на регулацију буке. Све ово усмерава нас ка фундаменталним проблемима које разматрам у овом чланку, а то су: проблем границе између пријатног звука и буке, продирање религијског звука у секуларни простор, односно, јавног звука у приватни простор. У овом тексту презентујем званични – градски, државни и црквени дискурс о звоњави звона од Другог светског рата до данас, док, са друге стране, наводим поједине примере како људи перципирају звоњаву. Користећи пример звоњаве црквених звона, истичем потребу за холистичким приступом решавању проблема звучног загађења.This article was written for the project City Sonic Ecology — Urban Soundscapes of Bern, Ljubljana and Belgrade, financed by Swiss National Science Foundation within its SCOPES programme (2013–2016)

Pritrkavanje. Nacionalna posebnost ali umišljena tradicija?

Pritrkavanje je že nakaj časa tako v znanosti kot širši javnosti opredeljeno kot 'slovenska posebnost, ki ji ni para zunaj naši etničnih meja'. Tovrstno prepričanje pa je temeljilo na raziskavah, ki niso nikoli presegale geografskih okvirov naše države. Zadošča, da primerjamo opredelitve 'slovenskega pritrkavanja' z nekaterimi drugimi praksami igre na zvonove, in ugotovimo, da je zelo razširjeno tudi v evropskem prostoru. Poudarjanje unikatnosti slovenskega pritrkavanja lahko razlagamo z vidika koncepta umišljene tradicije, kot enim od dejavnikov oblikovanja nacionalne identitete, s katerim narod išče samobitnost, unikatnost, avtentičnost in izvirnost lastne tradicije v primerjavi z drugimi. V prispevku obravnavam izhodišča za nastanek umišljenosti nekaterih aspektov pritrkovalske prakse v slovenskem prostoru, opozarjam na obstoj pritrkavanja v drugih evropskih državah ter na podlagi lastne terenske izkušnje podrobneje predstavljam sorodno prakso pritrkavanja v Nemčiji. *** In the professional and scholarly community, as well as in Slovenian public discourse bell chiming became regarded as a special Slovenian feature unrivalled outside Slovenian ethnic borders. The assumption was based on researches, which never exceeded geographical frames of Slovenian territory. But, only comparing the definitions of ‘Slovenian bell chiming’ to some other European practices of bell playing, one can establish that in Europe, bell chiming is a widespread practice. The case of promoting the uniqueness of Slovenian bell chiming can be explained from the viewpoint of the concept of invented tradition, as one of the factors of shaping national identity that a nation uses to find the character, uniqueness, authenticity, and originality of its own tradition in comparison to others. In this contribution, I discuss the origins for the invention of some aspects of the bell chiming practice, and give arguments for the existence of bell chiming practice in other European countries. Based on the fieldwork experience, I finally present the bell chiming practice in Germany