Average sampling of band-limited stochastic processes

We consider the problem of reconstructing a wide sense stationary band-limited process from its local averages taken either at the Nyquist rate or above. As a result, we obtain a sufficient condition under which average sampling expansions hold in mean square and for almost all sample functions. Truncation and aliasing errors of the expansion are also discussed

Principled methods for mixtures processing

This document is my thesis for getting the habilitation à diriger des recherches, which is the french diploma that is required to fully supervise Ph.D. students. It summarizes the research I did in the last 15 years and also provides the short­term research directions and applications I want to investigate. Regarding my past research, I first describe the work I did on probabilistic audio modeling, including the separation of Gaussian and α­stable stochastic processes. Then, I mention my work on deep learning applied to audio, which rapidly turned into a large effort for community service. Finally, I present my contributions in machine learning, with some works on hardware compressed sensing and probabilistic generative models.My research programme involves a theoretical part that revolves around probabilistic machine learning, and an applied part that concerns the processing of time series arising in both audio and life sciences

Uusien vaatimusten vaikutus Pohjoismaisten sähkömarkkinoiden taseselvitykseen

In December 2017 EU commission established a guideline on electricity balancing in order to develop and harmonize European electricity markets. It includes many new requirements and harmonizable subjects for Nordic imbalance settlement model. The objective of this study is to identify the impacts on Nordic imbalance settlement. This is done by studying the current imbalance settlement model, EU commission guideline and proposals and decisions of different working groups. The influence on different functions of Nordic imbalance settlement model is then evaluated. The major changes concern the imbalance settlement period, the calculation of imbalance and the pricing of imbalance. The imbalance settlement period will change from hour to 15 minutes. It will affect all messages and views which include time series as well as the calculation of imbalances which will be made for every 15-minute period in the future. The imbalance calculation will change in a way that there won’t be a separate production and consumption imbalances. The two imbalances are replaced by a single imbalance which is the combination of the two. Currently the production imbalance has different prices for positive and negative imbalance while the consumption imbalance has same price for both. The new pricing model will have same price for positive and negative imbalances during normal situation, but in specific conditions a dual pricing may be applied. The new requirements will simplify the model and they should financially encourage the market participants to balance the electricity grid. It should also be possible to perform the changes to the imbalance settlement system. However, in case some data can only be metered with hourly resolution it may cause some imbalances. There is also a risk that the financial incentives don’t support the balance of the grid or that there will be unexpected increases or decreases in the imbalances. As a whole, with great changes there is always an increased risk that something goes wrong, so a lot of planning and preparation is needed in order to go through with the changes.Joulukuussa 2017 EU-komissio laati asetuksen sähköjärjestelmän tasehallintaa koskevista suuntaviivoista Euroopan sähkömarkkinoiden kehittämiseksi ja harmonisoimiseksi. Se käsittää lukuisia uusia vaatimuksia ja harmonisoitavia osa-alueita myös Pohjoismaisen taseselvitysmallin osalta. Tämän työn tarkoitus on tunnistaa Pohjoismaiseen taseselvitykseen kohdistuvat vaikutukset. Vaikutuksia on selvitetty perehtymällä nykyiseen taseselvitysmalliin, EU-komission asetukseen sekä eri työryhmien ehdotuksiin ja päätöksiin. Niiden perusteella on arvioitu vaikutuksia Pohjoismaisen taseselvitysmallin eri osa-alueisiin. Suurimmat muutokset koskevat taseselvitysjakson pituutta, tasepoikkeaman laskentaa ja tasepoikkeaman hinnoittelua. Taseselvitysjakson pituus lyhenee tunnista 15 minuuttiin. Se vaikuttaa kaikkiin sanomiin ja näyttöihin, jotka sisältävät aikasarjoja, sekä tasepoikkeaman laskentaan, joka tehdään jokaiselle 15 minuutin jaksolle tulevaisuudessa. Tasepoikkeaman laskenta muuttuu siten, ettei jatkossa ole enää erillistä tuotanto- ja kulutustasetta. Kahden tasepoikkeaman tilalle tulee yksi tasepoikkeama, joka on näiden yhdistelmä. Nykyisessä hinnoittelussa tuotantotaseella on eri hinta positiiviselle ja negatiiviselle tasepoikkeamalle ja kulutustaseella positiivisen ja negatiivisen tasepoikkeaman hinta on sama. Uudessa hinnoittelumallissa positiivisen ja negatiivisen tasepoikkeaman hinta on normaalisti sama, mutta tietyissä olosuhteissa voidaan soveltaa kahta eri hintaa. Uudet vaatimukset yksinkertaistavat mallia ja niiden pitäisi antaa markkinaosapuolille taloudellinen kannustin sähköverkon tasapainottamiseen. Taseselvitysjärjestelmän pitäisi myös kyetä käsittelemään tarvittavat muutokset. Kuitenkin siinä tapauksessa, että osa aikasarjoista voidaan mitata vain tuntitasolla, voi siitä muodostua tasepoikkeamia. On myös olemassa riski siitä, että taloudelliset kannustimet eivät tuekaan sähköverkon tasapainoa tai että tasepoikkeamien volyymit odottamattomasti nousevat tai laskevat. Kokonaisuutena, suurien muutosten myötä kasvaa riski siitä, että jotain menee pieleen. Siksi muutosten läpivienti vaatii huolellista suunnittelua ja valmistautumista

Self-Similar Vector Fields

We propose statistically self-similar and rotation-invariant models for vector fields, study some of the more significant properties of these models, and suggest algorithms and methods for reconstructing vector fields from numerical observations, using the same notions of self-similarity and invariance that give rise to our stochastic models. We illustrate the efficacy of the proposed schemes by applying them to the problems of denoising synthetic flow phantoms and enhancing flow-sensitive magnetic resonance imaging (MRI) of blood flow in the aorta. In constructing our models and devising our applied schemes and algorithms, we rely on two fundamental notions. The first of these, referred to as "innovation modelling" in the thesis, is the principle —applicable both analytically and synthetically— of reducing complex phenomena to combinations of simple independent components or "innovations". The second fundamental idea is that of "invariance", which indicates that in the absence of any distinguishing factor, two equally valid models or solutions should be given equal consideration

Dividing society, dividing estates. Probate and will-making in Hermannstadt, 1720-1800: a social, economic and administrative perspective

Through the course of the present work, will-making in Hermannstadt between 1720 and 1800 has been elevated as a canvass, upon which political, social, and economic trends intersected to leave a myriad of patterns. The present thesis has explored the collective profile of testators, as a group apart, by re-embedding it into a successive series of contextual frames. In Hermannstadt, making a will, like any kind of engagement with authority after the Habsburg takeover at the end of the seventeenth century, indirectly reflected administrative renewal, state-building, as well as the entrenchment of political particularisms. Because will-making sometimes involved the devolution of property, and property rights were one of the essential, if not quintessential arguments in the arsenal of autonomy marshalled by the Transylvanian Saxon nation-estate, will-making was also politically potent. An inquiry into the practices of probate and will-making showed how much variation existed within this field, compared to the rather sparse legislative framework. Because testaments were merely one potential conduit for the devolution of wealth at death, testators were examined as a sub-group of individuals whose estates were probated between 1720-1800. Among its major findings is the fact that 1 in 4 adult individuals of Lutheran or Roman Catholic faith who perished between 1753 and 1800 had their estates undergo probate. Restaments were not heavily used in Hermannstadt, as only a 3% yearly average of deceased disposed of their estate thusly. However, this share also varied significantly, reaching up to 8% in certain years. A series of deeper but less transparent patterns largely determined the who, how, and why of testamentary behaviour: firstly, most testaments were made shortly before death, with one third written no longer than a week prior to an individual’s passing. Secondly, there was a clear class gradient to testation, as well as to probate. The elite group was under-represented among those who underwent probate, while within the testament group, the elite was slightly over-represented compared to the total decedent group. Thirdly, the thesis found that testators were much older than the overall decedent population, with most male testators still married, while most female testators widowed by the time a final disposition had been drafted. Moreover, the share of single women among female testators was nevertheless very high compared to the overall decedent group, signalling the priority of will-making for never-married women. Finally, slightly over 45% of all testaments were made by individuals (or couples) who had no bodily heirs, while only some 5% of testators had minor children. By comparison, among all probate events, only 10.5 % involved individuals without bodily heirs

1995 BRAC Commission

Data Call - Naval Command, Control and Ocean Surveillance Center, Research Development Test Evaluation Division - San Diego, CA. Data Call #5. Box 186, L-118

NASA University program management information system, FY 1993

The University Program Report, Fiscal Year 1993, provides current information and related statistics for 7682 grants/contracts/cooperative agreements active during the report period. NASA field centers and certain Headquarters program offices provide funds for those R&D activities in universities which contribute to the mission needs of that particular NASA element. This annual report is one means of documenting the NASA-university relationship, frequently denoted, collectively, as NASA's University Program