Absorbed dose distributions in lineal energy for neutrons and gamma rays were measured by using both a tissue-equivalent walled counter (TEPC) and a graphite-walled low pressure proportional counter (GPC) in the Am-Be neutron source facility at UOIT. A series of measurements were performed with the counters filled with propane-based TE gas (55.1% C3H8, 39.5% CO2 and 5.4% N2) at operating gas pressures corresponding to tissue spheres 2.0 , 4.0 and 8.0 μm in diameter. The results of these measurements indicated satisfactory performance of counters to measure microdosimetric spectra extending down to event-sizes that cover the gamma component of a mixed field. The spectra and the related mean values ̅y F and ̅y D are compared with other similar work but with monoenergetic neutrons of different energy range, the agreement between them is good. An assessment of the performance of different size TEPC has been done. An excellent agreement between their event size spectra was found and the proton edge appears at the same position on the lineal energy scale and differences in microdosimetric parameters ̅ and ̅ is not exceeding 3%, which is in the region of counting statistics. In Am-Be neutron field, the efficiency of the TEPCs was measured to have an average value of 250 counts per μSv or equivalently about 4.17 counts per minutes per μSv/hr. This efficiency is reasonable for dose equivalent measurements but needs a long integration period. The measurements showed that the dose equivalent which depends on the measurement of energy deposition by the secondary charged particles was originated mainly from elastic collisions of the incident neutrons with hydrogen atoms. Moreover the number of events in the sensitive gas is dominated by proton recoils. A non- negligible fraction of the dose equivalent resulted from gamma interactions, alpha and recoil nuclei. The energy deposition patterns in these micro-scale targets are strongly dependent on radiation quality, so differences of linear energy transfer (LET) of the components in a mixed radiation field are significant. Accordingly, in a radiation field with an unknown gamma ray energy spectrum, absorbed dose for neutrons can be obtained by the separation of neutron induced events from gamma events using their distribution in lineal energy. To separate neutron dose from gamma dose a simple lineal energy threshold technique has been used in addition to a more sophisticated methods using γ-fitting and the graphite-walled counter measurements. The results of this study will establish the degree of error introduced by using a lineal energy threshold, which is likely to be used in any hand-held neutron monitor based on TEPCs. / UOIT

The general objective of the present work is to contribute to the knowledge of the physics of Be Stars. In particular, we are interested in studying and characterizing their pulsational properties. A very suitable tool to reach this goal is the study and analysis of photometric time series with the maximum time baseline, density and photometric accuracy.The space mission COROT scheduled to be launched in December 2006, will provide ultra high precision, relative stellar photometry for very long continuous observing runs. Up to ten stars will be observed in the seismology fields with a photometric accuracy of a few 10-4 and color information during 150 days.The observations of Be stars with COROT will provide photometric time series with unprecedented quality. Their analysis will allow us to qualitatively improve our knowledge and understanding of the pulsational characteristics of Be stars. In consequence, we have started a research project aimed at observing Be stars both in the seismology and exoplanet fields of COROT.In this thesis we present the first step of this project, which is the preparation and study of the sample of Be stars that will be observed by COROT. We have performed photometric analysis of all Be stars located in the seismology fields (Chap. 2). Special emphasis has been given to two stars (NW Ser and V1446 Aql) in which we have detected multiperiodic variability and these variations have been modeled in terms of stellar pulsations (Chap. 3). We have also performed an in-depth spectroscopic study of NW Ser and identified the non-radial pulsating modes taking into account the rotational effects (Chap. 4). A technique to search for faint Be stars based on CCD photometry has been developed and is presented in Chap. 5. We also present a list of faint Be stars located in the exoplanet fields of COROT detected with this technique and which we propose as targets for COROT. In addition, we have proven that our period-analysis techniques are suitable to detect multiperiodicity in large temporal baseline data. In particular, we have detected non-radial pulsations in some Be stars in the low-metallicity galaxy Small Magellanic Clouds (Chap. 6). The current theoretical models do not predict the presence of pulsational instabilities in such low-metallicity environment, and therefore, our results point towards the necessity of new and improved models.

Be stars are rapidly rotating B-type stars that eject large amounts of material into a circumstellar disk. Evidence of the presence of a disk is found through hydrogen emission lines in their spectra, IR excess flux, and linear intrinsic polarization. In this dissertation, we report the first simultaneous interferometric and spectroscopic observations of circumstellar disks around 24 bright Be stars made using the techniques of long baseline interferometry and moderate resolution spectroscopy in the near infrared. The goal of the project is to characterize the fundamental geometrical and physical properties of the emitting regions that are responsible for the IR flux excesses detected in the K-band in our sample stars. This observational work has been conducted with both the Center for High Angular Resolution Astronomy (CHARA) Array at Mount Wilson Observatory, and the Mimir spectrograph at Lowell Observatory. The visibility measurements were interpreted with different geometrical and physical disk models in order to determine the spatial extension of the disk, the inclination angle, the position angle, and the density profile of the disk. We find that the spatial extension of the circumstellar disk in the K-band is only about a few stellar radii, and that the density structure of the disk is consistent with a radially decreasing function with a density exponent that ranges between 2.5 and 3.5. The resulting disk densities are in a good agreement with those derived from the Infrared Astronomical Satellite (IRAS) measurements, and the resulting disk geometries are consistent with previous polarimetric measurements. We find that the K-band sizes of the emitting regions in the disk are smaller by a factor of two than the Hα sizes, and we show that this is due to the lower opacity of the continuum in the disk. By combining recent measurements of the projected rotational velocities with the disk inclination angles derived from interferometry, we were able to estimate the actual equatorial linear rotational velocities of the Be stars in our sample. The obtained linear rotational velocities indicate that Be stars are rapid rotators with an equatorial velocity that is about 0.7 - 0.9 of their critical velocities.

Unlimited retention of personal information on the web may harm individuals: employers can find youthful indiscretions on social media, and incorrectly low credit scores may haunt individuals for a lifetime. Currently, Europe revives the "right to erasure" as a first step towards a forgetting web. Early technologies implementing oblivion suffer from vulnerabilities and narrowly assume that users require information to be erased after a pre-determined time. But little is known about users' actual oblivion needs. A first study shows that users desire control over disclosed personal information to reduce pre-disclosure privacy concerns, and to delete harmful information after disclosure. In the long run, users have a need for dissociating from obsolete information that represents their past identity. A second study analyses whether oblivion-enhancing technologies (OETs) currently deployed in online services satisfy users' needs. While not all services give users assurance that disclosed information can be erased again, most provide users with some active control. But to manage the increasing volume of personal information stored, users would also require "intelligent" support with oblivion. Intelligent agents that keep track of disclosed information long-term could automatically safeguard users from information relating to a past episode in life surfacing unexpectedly. (authors' abstract)

Šiame darbe autorė kėlė tikslą teoriškai ir praktiškai išanalizuoti Lietuvos ir Lenkijos darbo sutarčių nutraukimo nuostatas bei pateikti pasiūlymus siekiant tobulinti darbo sutarties sudarymo, vykdymo ir nutraukimo teisines normas. Darbą sudaro keturios dalys: Įvadas, I, II, III dalys, Išvados bei Pasiūlymai ir literatūros sąrašas. Įvade autorė kalba apie šio darbo keliamus tikslus, pagrindžia būtent šios temos pasirinkimą, pateikia analizės metodus bei naudojamos literatūros aprašymus bei komentarus. Darbe analizuojami tie darbo sutarties nutraukimo atvejai, kai darbo sutartis nutraukiama dėl nepriklau¬sančių nuo darbo sutarties šalių priežasčių, taip pat atvejus, kai darbuotojas šiurkščiai arba sistemingai pažeidžia savo įsipareigojimus pagal darbo sutartį. Pirmoje darbo dalyje kalbama apie darbo sutartį, kaip apie pagrindinį darbo teisės institutą. Apibrėžiami darbo teisės, o konkrečiai darbo sutarties subjektai, pateikiama ir analizuojama jos sąvoka bei ypatumai, analizuojamas darbo sutarties turinys bei pakeitimai, lyginant su ankstesniais darbo įstatymais. Antrojoje dalyje analizuojamos darbo sutarties nutraukimo be įspėjimo, kai darbo sutartis nutraukiama dėl nepriklausančių nuo sutarties šalių valios priežasčių, nuostatos. Trečioje šio darbo dalyje analizuojamas darbo sutarties nutraukimas be įspėjimo kai darbo sutartis nutraukiama dėl darbuotojo kaltų veiksmų. Darbo pabaigoje autorė pateikia išvadas, apibendrinimus bei pasiūlymus. / The main goal of this study is to make the theoric and practice analysis of Labor Code of Lithuanian Republic and of Poland in general, the main attention lay on labour contract ending without notice. This study consists of introductions, parts I, II, III, conclusions and proposals. In the introduction author explains the goal of this study, describes methods of research and special literature. In the first part of this work the author gives a definition of labor contract as a main institution of Labor Law, gives a definition of the subjects of Labor contract, makes an analysis of this institution. The author of this research gives a definition of the content of the contract, compares the Contract law iv force with the old Labor laws. The second part reviews the grounds of termination of employment contract without notification, in case of outrage violation of labour duties, under the Labour Code of Republic of Lithuania. It is still very unclear how it will be applied in practice. Nearly all the rules in labour law are new. Here we found the actuality of this article. It is important to accent that Labour code provides that the employment contract can be terminated only for valid reasons. Only the circumstances, which are related to the qualification, professional skills or conduct of an employee, shall be recognised as valid. Moreover, an employment contract may also be terminated on economic, technological grounds or due to the restructuring of the workplace, as well as... [to full text]

Vienatvės, vienišumo šaknis turbūt reiktų sieti ne tik su homo sapiens pradžia, bet tam tikra prasme ir su gyvybės atsiradimu apskritai. Vienišumas – tai emocinė individo būsena, o kartu ir sociumo reiškinys, kurį būtų galima įvardinti kaip gana dažną šių dienų elementą. O vienatvė – daugiau fiziologinį atspalvį turintis reiškinys, tai padėtis (situacija), kuomet vienas objektas (šiuo atveju žmogus) yra atskirtas nuo kitų tokių pat objektų (t.y. kitų žmonių). Vienatvė gali būti „padiktuota“ aplinkybių, t.y. priverstinė, taip pat ji gali būti ir pasirinktinė, kuomet tai yra sąmoningas individo sprendimas (pvz. „savęs ieškojimas“, minčių „kristalizacija“, įkvėpimo bei kūrybinio potencialo generacija). Sąvoka vienišumas gali turėti kelis interpretavimo variantus: vienišas individas (žmogus) gali jaustis aplinkinių žmonių atžvilgiu (draugų bei bendraminčių neturėjimas, individualios jo pasaulėžiūros ignoravimas ir pan.); vienišas žmogus gali būti ir vertinant jo egzistavimą pasaulio masteliu (susvetimėjimas, prasmės neturėjimas ir pan.); vienišumas gali būti padiktuotas tam tikrų situacijų (netekus artimųjų, išsiskyrimas su brangiais žmonėmis). Darbe nagrinėjama mokslinę teorinę informaciją apie fizinį ir psichologinį būvį – savarankišką dvasinį stovį, vienišiaus psichinė ir socialinė egzistencija Kurią plačiai nagrinėja mokslininkai, psichologai. Pirmame teorinės dalies skyriuje nagrinėjamos vienišumo sąvokos, susijusios su vienišumo reiškiniu. Plačiau gilinamasi į vienatvės... [toliau žr. visą tekstą] / Solitude, loneliness root probably should be associated not only with homosapiens start, but in a sense, and the origin of life in general. Loneliness - is the emotional state of the individual, and thus the socium phenomenon, which could be described as fairly often these days element. And loneliness - with a shade more physiological phenomenon, this is the position (situation), where one object (in this case the human) is separated from the others of the same object (it is, other people). Loneliness can be "dictated" circumstances, it is enforced as well as it can be custom when it is conscious decision the individual (eg "self-seeking", thoughts "crystallization", inspiration and generation of creative potential). The concept of loneliness can have several versions of interpretation: individual (person) can feel lonely in relation to the surrounding people (friends and like-minded absence, self ignoring his worldview and the like.); lonely man can be also assessing his existence in the world scale (dissociation, meaning absence, etc.); loneliness may be dictated by certain situations (bereavement, separation from loved ones). This work examines the scientific, theoretical information about the physical and psychological state - an independent spiritual condition, single mental and social existence which is widely examined by scientists and psychologists. The first chapter deals with the theoretical part of loneliness concepts related to the phenomenon of loneliness. More... [to full text]

Proefschrift Universiteit van Amsterdam. / Auteursnaam op omslag: John Telting. Met lit. opg. - Met samenvatting in het Nederlands.

Thesis--Lund. / Extra t.p., with thesis statement, inserted, has imprint: Lund, H. Ohlssons boktryckeri, 1948. Bibliography: p. [229]-236.

University, Diss., 2003--Heidelberg.

The special architecture of the Cell BE processor has made scientists revisit the problem of sorting. This paper implements and tests a variant of merge sort where a number of 2-to-1 mergers are connected in a pipelined tree. For large trees there are many more such mergers than processors which means they must be mapped to the processors in some way. Optimized mappings are tested and results show that changing the model used when optimizing might be beneficiary. It is also shown that the small size of the local storages on the co-processors is not limiting the performance.