371 |
Contribution à l'étude de techniques de siliciuration avancées pour les technologies CMOS décananométriquesBreil, Nicolas 15 May 2009 (has links) (PDF)
Dans le cadre de la réduction des dimensions des technologies CMOS, le module de jonction apparaît comme un point bloquant pour l'amélioration des performances. En particulier, la hauteur de barrière entre le siliciure et le silicium limite le courant passant du transistor. Cette thèse adresse spécifiquement la problématique du contrôle de la hauteur de barrière suivant deux directions. D'une part, nous étudions l'intérêt d'une modification du métal formant le siliciure. D'autre part, nous évaluons le potentiel des techniques de ségrégation de dopants pour la modulation de la hauteur de barrière. Dans un premier temps, nous démontrons les difficultés liées à l'intégration des siliciures de type n (ErSi). Par ailleurs, nous mettons en évidence le fort potentiel du siliciure de platine (PtSi). En effet, ce matériau présente une stabilité thermique supérieure au siliciure de référence (NiSi) et montre une faible barrière à l'injection de trous. De plus, nous montrons que les techniques de ségrégation de dopants permettent d'obtenir de faibles hauteurs de barrières pour l'injection des électrons. Le PtSi apparaît donc comme un candidat à fort potentiel pour les futures technologies CMOS. Après avoir montré les inconvénients majeurs posés par l'intégration auto-alignée du PtSi grâce au procédé standard par eau régale, nous proposons une nouvelle méthode de retrait sélectif basée sur la transformation du métal non réagi en un germaniure facilement retiré par des chimies conventionnelles. En conclusion, nous intégrons le PtSi dans un procédé de fabrication industriel afin de démontrer des performances électriques à l'état de l'art des technologies CMOS les plus avancées.
|
372 |
Bröd vid död i Kalvshälla : Analys av förhistoriskt organiskt grav- och boplatsmaterial från Barkarby i Järfälla socken, UpplandSchierman, Christina January 2006 (has links)
This paper deals with prehistoric charred organic material, interpreted as bread, found in graves and in the underlying settlement at Kalvshälla, Järfälla parish in Uppland. The aim was to categorize the organic material morphologically and with the help of Fourier transformed Infrared spectroscopy (FT-IR) to see whether it was bread or not. Material from 13 graves (dated to Late Roman Iron Age until Viking Age) and 3 finds from the settlement have been analysed. Differences were noted both in shape, porosity and structure. Some of the material has been interpreted as cereal based foodstuff instead of bread due to morphological discrepancies. No clear differences between material from the graves and the settlement can be seen. One find from a posthole can be dated to late Bronze Age, which is unusual. The bread in the graves was intentionally given to both adult females and males maybe as a symbol of their roles as the good householders. Several finds of root tubers of dropwort (Filipendula vulgaris) were identified in female graves from Early Iron Age, but also in two male graves with bread from Vendel period. The FT-IR method does not give a clear answer to whether the organic material can be bread or not. The method requires careful sampling procedures and several samples from each concretion to get good results.
|
373 |
New Developments in Nitridometalates and Cyanamides: Chemical, Structural and Physical Properties / Neue Entwicklungen in Nitridometallaten und Cyanamiden: chemische, strukturelle und physikalische EigenschaftenBendyna, Joanna 30 November 2009 (has links) (PDF)
In the course of these investigations altogether 18 different compounds have been synthesized and their chemical, structural and physical properties were characterized (XRD, XANES, IR, Raman spectrum, magnetic susceptibility, electrical resistivity, low temperature and TG/DTA).
Up to now only nitridonickelates and nitridocuprates were known to exhibit exclusively low oxidation states of the transition metals between 0 and +2. In this work it has been presented that also nitridocobaltates belong to this group. We have proved that “Ca3CoIIIN3” do not exist and the real chemical formula can be regarded as Ca5[CoIN2]2.
In the thesis another seven new nitridocobaltates(I) have been described, these add to four already known structures. Among novel phases only Ba9Ca[Co2N3]3 may indicate higher valency state for cobalt with the [Co2N3]5- complexes. The XANES data supporting CoII state by comparison with other compounds possess this oxidation state. The crystal structure of Ba9Ca[Co2N3]3 is related to the perovskite type structure.
The remarkable structural features of Sr2[CoN2]0.72[CN2]0.28 ≈ Sr6[CoN2]2[CN2] nitridocobaltates [CoIN2]5- ions partially substituted by carbodiimides [N=C=N]2- ions. Up to now in the crystal structure no indications for a homogeneity range could be observed.
Both crystal structures of (Sr6N)[CoN2][CN2]2 and Sr6[CoN2]2[CN2] encompass nitridocobaltate [CoN2]5- and carbodiimide [N=C=N]2- ions. In the structures distorted rocksalt motif based on Sr-N partial structure can be distinguished.
Up to now in the system AE-Fe-N-(C) only four crystal structures were reported and in the thesis three new were refined Sr8[FeIIIN3]2[FeIIN2], Sr3[FeN3] and (Sr6N)[FeN2][CN2]2 and their physical properties were characterized. The system AE-Mn-N-(C) via this work was extended by Sr8[MnN3]3 and Sr4[MnN3][CN2].
Up to date the only nitridometalate containing different transition elements is Ba[Ni1-xCuxN]. In this work one more mixed nitridometalate has been described Sr8[MnIIIN3]2[FeIIN2].
The crystal structure of Sr4[MnN3][CN2] revealed some weak diffuse scattering lines. The general formula of Sr4[MnN3][CN2] can be written as Sr4[Mn0.96N2.90][C0.96N2] to emphasize possible homogeneity range. Any explanation of the phenomena and establishment of possible homogeneity range are still a challenge.
The structures of Sr8[MIIIN3]2[FeIIN2] (M = Mn, Fe) are related to Sr8[MnIVN3]2[MnIIIN3]. All these compounds are first mixed-valency compounds for respective systems and exhibit close relation to crystal structures of Sr3[MN3] (M = Mn, Fe). From the XANES data alike behaviour of all structures containing Mn was observed.
Due to some possible degree of Mn/Fe mixing in the crystal structure of Sr8[MIIIN3]2[FeIIN2] the chemical formula might be written as Sr8[MnN3]2-x[FeN3]x[FeN2]. This needs to be investigate in details.
Up to now in the literature the only crystallographic data of nitridometalates contain [NCN]2- ions include two compounds. In this work four novel nitridometalate carbodiimides and cyanamides Sr4[MnN3][CN2], (Sr6N)[MN2][CN2]2 (M = Co, Fe) and Sr6[CoN2]2[CN2] have been synthesized.
Predominant magnetic properties in the investigated nitridometalates are connected to some antiferromagnetic M-M interactions supported by AFM ordering. The electrical resistivity often shows at some semi-conducting character of these compounds. XANES spectroscopy provided many useful data about valency states of the transition elements, coordination environment around absorbing atoms and electronic structure. The influence of different parameters on the transition metals K-edges was studied in details. IR and Raman give general data about [NCN]2- ions.
|
374 |
Ultrastructure of the Primary Cell Wall of Softwood Fibres Studied using Dynamic FT-IR SpectroscopyStevanic Srndovic, Jasna January 2008 (has links)
<p>The primary cell wall is a complex multipolymer system whose composite structure has been mostly determined from chemical and biochemical studies. Although the primary cell wall serves a central role, with regard to the connective properties of fibres, knowledge about the interactions among the polymers, when it comes to the mechanical properties, is very limited. The physical properties of the polymers, i.e. their elastic and viscous deformations, as well as the ultrastructure of the polymers, i.e. the interactions among the polymers in the outer fibre wall layers that lead to this behaviour, are still not fully understood.</p><p>The aim of this study was to examine how the different wood polymers, viz. lignin, protein, pectin, xyloglucan and cellulose, interact in the outer fibre wall layers of the spruce wood tracheid. The initial objective was to separate an enriched primary cell wall material from a first stage TMP, by means of screening and centri-cleaning. From this material, consisting of the primary cell wall (P) and outer secondary cell wall (S1) materials, thin sheets were prepared and analysed using a number of different analytical methods. The major measuring technique used was dynamic Fourier transform infra-red (FT-IR) spectroscopy in combination with dynamic 2D FT-IR spectroscopy. This technique is based on the detection of small changes in molecular absorption that occur when a sinusoidally stretched sample undergoes low strain. The molecular groups affected by the stretching respond in a specific way, depending on their environment, while the unaffected molecular groups provide no response to the dynamic spectra, by producing no elastic or viscous signals. Moreover, the dynamic 2D FT-IR spectroscopy provides useful information about various intermolecular and intramolecular interactions, which influence the reorientability of functional groups in a polymer material.</p><p>Measurements of the primary cell wall material, using dynamic FT-IR spectroscopy, indicated that strong interactions exist among lignin, protein and pectin, as well as among cellulose, xyloglucan and pectin in this particular layer. This was in contrast to the secondary cell wall, where interactions of cellulose with glucomannan and of xylan with lignin were dominant. It was also indicated that the most abundant crystalline cellulose in the primary cell wall of spruce wood fibres is the cellulose Iβ allomorph, which was also in contrast to the secondary cell wall, where the cellulose Iα allomorph is more dominant. The presence of strong interactions among the polymers in the primary cell wall and, especially, the relatively high content of pectin and protein, showed that there is a very good possibility of selectively attacking these polymers in the primary cell wall. The first selective reaction chosen was a low degree of sulphonation, applied by an impregnation pretreatment of chips with a very low charge of sodium sulfite (Na2SO3). This selective reaction caused some structural modification of the lignin, a weakening of the interactions between lignin;pectin, lignin;protein and pectin;protein, as well as an increased softening of the sulphonated primary cell wall material, when compared to the unsulphonated primary cell wall material. All this resulted in an increased swelling ability of the material.</p>
|
375 |
The sorption of uranium(VI) and neptunium(V) onto surfaces of selected metal oxides and alumosilicates studied by in situ vibrational spectroscopyMüller, Katharina 11 November 2010 (has links) (PDF)
The migration behavior of actinides and other radioactive contaminants in the environment is controlled by prominent molecular phenomena such as hydrolysis and complexation reactions in aqueous solutions as well as the diffusion and sorption onto minerals present along groundwater flow paths. These reactions significantly influence the mobility and bioavailability of the metal ions in the environment, in particular at liquid-solid interfaces. Hence, for the assessment of migration processes the knowledge of the mechanisms occurring at interfaces is crucial. The required structural information can be obtained using various spectroscopic techniques.
In the present study, the speciation of uranium(VI) and neptunium(V) at environmentally relevant mineral – water interfaces of oxides of titania, alumina, silica, zinc, and alumosilicates has been investigated by the application of attenuated total reflection Fourier-transform infrared (ATR FT-IR) spectroscopy. Moreover, the distribution of the hydrolysis products in micromolar aqueous solutions of U(VI) and Np(V/VI) at ambient atmosphere has been characterized for the first time, by a combination of ATR FT-IR spectroscopy, near infrared (NIR) absorption spectroscopy, and speciation modeling applying updated thermodynamic databases.
From the infrared spectra, a significant change of the U(VI) speciation is derived upon lowering the U(VI) concentration from the milli- to the micromolar range, strongly suggesting the dominance of monomeric U(VI) hydrolysis products in the micromolar solutions. In contradiction to the predicted speciation, monomeric hydroxo species are already present at pH ≥ 2.5 and become dominant at pH 3. At higher pH levels (> 6), a complex speciation is evidenced including carbonate containing complexes.
For the first time, spectroscopic results of Np(VI) hydrolysis reactions are provided in the submillimolar concentration range and at pH values up to 5.3, and they are comparatively discussed with U(VI). For both actinides, the formation of similar species is suggested at pH ≤ 4, whereas at higher pH, the infrared spectra evidence structurally different species. At pH 5, the formation of a carbonate-containing dimeric complex, that is (NpO2)2CO3(OH)3−, is strongly suggested, whereas carbonate complexation occurs only under more alkaline conditions in the U(VI) system.
The results from the experiments of the sorption processes clearly demonstrate the formation of stable U(VI) surface complexes at all investigated mineral phases. This includes several metal oxides, namely TiO2, Al2O3, and SiO2, serving as model systems for the elucidation of more complex mineral systems, and several alumosilicates, such as kaolinite, muscovite and biotite. From a multiplicity of in situ experiments, the impact of sorbent characteristics and variations in the aqueous U(VI) system on the sorption processes was considered.
A preferential formation of an inner-sphere complex is derived from the spectra of the TiO2 and SiO2 phases. In addition, since the in situ FT-IR experiments provide an online monitoring of the absorption changes of the sorption processes, the course of the formation of the U(VI) surface complexes can be observed spectroscopically. It is shown that after prolonged sorption time on TiO2, resulting in a highly covered surface, outer-sphere complexation predominates the sorption processes. The prevailing crystallographic modification, namely anatase and rutile, does not significantly contribute to the spectra, whereas surface specific parameters, e.g. surface area or porosity are important.
A significant different surface complexation is observed for Al2O3. The formation of inner-spheric species is assumed at low U(VI) surface coverage which is fostered at low pH, high ionic strength and short contact times. At proceeded sorption the surface complexation changes. From the spectra, an outer-spheric coordination followed by surface precipitation or polymerization is deduced. Moreover, in contrast to TiO2, the appearance of ternary U(VI) carbonate complexes on the γ-Al2O3 surface is suggested.
The first results of the surface reactions on more complex, naturally occurring minerals (kaolinite, muscovite and biotite) show the formation of U(VI) inner-sphere sorption complexes. These findings are supported by the spectral information of the metal oxide surfaces.
In this work, first spectroscopic results from sorption of aqueous Np(V) on solid mineral phases are provided. It is shown that stable inner-sphere surface species of NpO2+ are formed on TiO2. Outer-sphere complexation is found to play a minor role due to the pH independence of the sorption species throughout the pH range 4 – 7.6. The comparative spectroscopic experiments of Np(V) sorption onto TiO2, SiO2, and ZnO indicate structurally similar bidentate surface complexes.
The multiplicity of IR spectroscopic experiments carried out within this study yields a profound collection of spectroscopic data which will be used as references for future investigations of more complex sorption systems in aqueous solution. Furthermore, from a methodological point of view, this study comprehensively extends the application of ATR FT-IR spectroscopic experiments to a wide range in the field of radioecology.
The results obtained in this work contribute to a better understanding of the geochemical interactions of actinides, in particular U(VI) and Np(V/VI), in the environment. Consequently, more reliable predictions of actinides migration which are essential for the safety assessment of nuclear waste repositories can be performed. / Das Migrationsverhalten von Aktiniden und anderen radioaktiven Schadstoffen in der Umwelt wird von wichtigen molekularen Prozessen entlang der Grundwasserfließwege reguliert. Dazu gehören sowohl die Hydrolyse und Komplexierung in wässrigen Lösungen als auch Diffusion und Sorption der Schwermetalle an Mineralen. Diese Reaktionen beeinflussen entscheidend die Mobilität und Bioverfügbarkeit der Metallionen in der Umwelt, insbesondere an den fest-flüssig Grenzflächen. Genaue Kenntnisse über die an diesen Grenzflächen stattfindenden Mechanismen sind somit entscheidend, um Migrationsprozesse verlässlich abschätzen zu können. Die benötigten strukturellen Informationen können mit verschiedenen spektroskopischen Techniken ermittelt werden.
Das Ziel der vorliegenden Arbeit war die Untersuchung der Speziation von Uran(VI) und Neptunium(V) an umweltrelevanten Grenzflächen von Oxiden des Titans, Aluminiums, Siliziums und Zinks und von Alumosilikaten mittels ATR FT-IR Spektroskopie. Des Weiteren wurde die Verteilung aquatischer Spezies in mikromolaren Lösungen des U(VI) und Np(V/VI) unter Normalbedingungen charakterisiert. Diese erstmalige Untersuchung wurde mit einer Kombination aus Speziationsmodellierung unter Anwendung aktueller thermodynamischer Daten und ATR FT-IR und NIR Absorptionsspektroskopie realisiert.
Die Infrarotspektren zeigen eine deutliche Änderung der Speziesverteilung im Konzentrationsverlauf vom millimolaren zum mikromolaren Bereich. Dies verweist auf die Bildung monomerer U(VI) Hydrolyseprodukte. Im Gegensatz zu berechneten Speziationen werden diese monomeren Komplexe schon bei pH ≥ 2,5 gebildet und dominieren die Speziation bei pH 3. Bei höheren pH-Werten (> 6) konnte eine komplexe Speziesverteilung mit Anteilen von Karbonatkomplexen nachgewiesen werden.
Erstmals konnten im Rahmen dieser Arbeit spektroskopische Befunde der Hydrolysereaktionen des Np(VI) im submillimolaren Konzentrationsbereich bis pH 5,3 erhalten werden. Diese wurden im Vergleich mit der U(VI) Speziation diskutiert. Obwohl im sauren Bereich (pH ≤ 4) die Bildung ähnlicher Komplexe nachgewiesen wurde, zeigen die bei höheren pH-Werten erhaltenen Spektren eine unterschiedliche Speziesverteilung. Im Gegensatz zum U(VI) bildet das Np(VI) schon bei pH 5 karbonathaltige aquatische Spezies wie (NpO2)2CO3(OH)3−.
Die Ergebnisse der Sorptionsexperimente von U(VI) zeigen die Bildung stabiler Oberflächenkomplexe an allen untersuchten Mineralphasen. Dies umfasst mehrere als Modellsystem dienende Metalloxide wie TiO2, Al2O3 und SiO2, als auch komplexere Alumosilikate wie Kaolinit, Muskovit und Biotit. Für eine detaillierte Charakterisierung der Oberflächenkomplexe wurde eine Vielzahl von in situ Sorptionsexperimenten durchgeführt, die den Einfluss unterschiedlicher Parameter der mineralischen Phase als auch des wässrigen U(VI) Systems berücksichtigen.
Die bevorzugte Bildung von innersphärischen Komplexen an TiO2 und SiO2 wird aus den spektroskopischen Daten abgeleitet. Da die in situ FT-IR Spektroskopie eine kontinuierliche Registrierung der Absorptionsänderungen während der ablaufenden Sorptionsprozesse erlaubt, kann somit der Verlauf dieser Prozesse quasi in Echtzeit spektroskopisch verfolgt werden. Es konnte gezeigt werden, dass mit fortschreitender Sorptionsdauer, d.h. bei hohen Beladungsdichten, die Bildung einer weiteren außersphärischen Spezies die Sorption dominert. Die vorliegende kristallographische Modifikation, Anatas und Rutil, ist nicht maßgeblich für das Auftreten unterschiedlicher Sorptionsprozesse verantwortlich, obwohl Parameter wie die spezifische Oberfläche und die Porosität für den Sorptionsprozess von Bedeutung sind.
Deutlich verschiedene Oberflächenreaktionen werden für Al2O3 beobachtet. Aus den Spektren kann die Ausbildung einer innersphärischen Spezies bei sehr niedrigen U(VI) Beladungen, niedrigen pH-Werten, hohen Ionenstärken und kurzen Kontaktzeiten abgeleitet werden. Bei fortschreitender Sorption ändert sich die Art der Oberflächenkomplexe. Zunächst bilden sich außersphärische Spezies, während im weiteren Verlauf die Spektren auf eine beginnende Oberflächenausfällung bzw. Polymerisation hinweisen. Weiterhin wird das Auftreten von ternären U(VI) Karbonatkomplexen an γ-Al2O3 aus den spektroskopischen Daten abgeleitet.
Die ersten Ergebnisse der Sorptionsexperimente an komplexeren, natürlich auftretenden Mineralphasen (Kaolinit, Muskovit und Biotit) zeigen eine bevorzugte Ausbildung von innersphärischen U(VI) Komplexen. Diese Resultate werden durch die spektralen Befunde der Experimente der Metalloxide gestützt.
Erstmalig werden in dieser Arbeit spektroskopische Ergebnisse der Sorptionsprozesse von wässrigen Np(V) an verschiedenen Mineralphasen präsentiert. Wie U(VI) bildet Np(V) stabile innersphärische Oberflächenkomplexe an TiO2. Die Speziesverteilung an der TiO2 Oberfläche ist im pH Bereich 4 – 7,6 konstant. Daher ist zu erwarten, dass eine außersphärische Komplexierung hier nur eine untergeordnete Rolle spielt. Der Vergleich von Spektren der Np(V) Sorptionskomplexe an TiO2, SiO2 und ZnO weist auf die Bildung strukturell ähnlicher bidentater Komplexe hin.
Die Vielzahl der hier vorgestellten infrarotspektroskopischen Experimente bietet eine fundierte Sammlung spektroskopischer Daten, die für zukünftige Untersuchungen komplexer aquatischer und mineralischer Systeme unerlässlich ist. Gleichzeitig wurde der Anwendungsbereich der ATR FT-IR Technik auf dem Gebiet der Radioökologie umfassend erweitert.
Die im Rahmen dieser Arbeit gewonnenen Ergebnisse tragen zu einem besseren Verständnis der geochemischen Wechselwirkungen von Aktiniden, im Speziellen von U(VI) und Np(V) in der Umwelt bei. Damit unterstützen sie den Aufklärungsprozess der Migration von radioaktiven Kontaminationen und dienen als Grundlage für zuverlässige Prognosen für die Sicherheitsbewertung von Endlagern für nukleare Abfälle.
|
376 |
Ikimokyklinio ugdymo programų kūrimą sąlygojantys veiksniai / Factors influencing creation of preschool child curriculumŽaliukienė, Dalitė 24 September 2008 (has links)
Nuolat besikeičiančioje ir tobulinamoje Lietuvos švietimo sistemoje daug dėmesio skiriama kokybiško ugdymo klausimams, todėl aktualus tapo ir ikimokyklinio ugdymo programų atnaujinimo procesas. Magistro baigiamajame darbe nagrinėjami ikimokyklinio ugdymo programų kūrimą sąlygojantys veiksniai: Lietuvoje vykdoma švietimo reforma, ikimokyklinio ugdymo įstaigų bendruomenės (pedagogų, tėvų, vaikų) poreikiai, pedagogų kompetencija, pedagogų motyvacija, laiko veiksnys ir kt. Magistro baigiamajame darbe tiriama pedagogų ir tėvų nuomonė apie ikimokyklinio ugdymo programų kūrimą įtakojusius veiksnius. Šio darbo tikslas: išnagrinėti ikimokyklinio ugdymo programų kūrimą įtakojusius veiksnius. / In today’s changing and constantly improved Lithuanian system of education a significant part of attention is being devoted to the quality of child development, and therefore importance of the process of creation of preschool curriculum arose. This Master thesis analyses factors influencing creation of preschool child curriculum: Lithuanian education reform, needs of preschool development institutions’ societies (pedagogues, parents, children), pedagogues competence, motivation of pedagogues, time factor and other. Master thesis emphasises the opinion of pedagogues, parents with regards to the factors influencing creation of preschool child curriculum. The aim of this master paper: to analyse main factors influencing creation of preschool child curriculum.
|
377 |
Istorijos ir geografijos modifikuotų bei adaptuotų programų rengimas dirbant su specialiųjų ugdymosi poreikių turinčiais mokiniais / Preparing of Modified and Adaptive Educational Programmes of History and Geopgraphy for the Special Needs StudentsLelėnienė, Laima 26 September 2008 (has links)
Darbe atlikta teorinė specialiojo ugdymo sampratos probleminių klausimų, individualizuoto ir diferencijuoto ugdymo aspektų bendrojo lavinimo mokykloje analizė. Profesinių žinių, rengiant istorijos ir geografijos modifikuotas ir adaptuotas programas, modifikuotų ir adaptuotų programų privalumų ir trūkumų analizė.
Iškelta hipotezė: istorijos ir geografijos modifikuotų ir adaptuotų programų rengimą, jų privalumus ir trūkumus lemia pedagogų didaktinis ir psichologinis pasirengimas.
Anketinės apklausos metodu buvo atliktas tyrimas, kurio tikslas – išsiaiškinti adaptuotų ir modifikuotų programų privalumus ir trūkumus, kokių žinių, gebėjimų ir praktinių įgūdžių pasigenda pedagogai, ugdydami specialiųjų poreikių vaikus, ar pasiruošęs mokytojas rengti adaptuotas ir modifikuotas programas. Tyrimo duomenys analizuojami statistiniais metodais (aprašomoji statistika, chi- kvadratas, aritmetinis vidurkis).
Tyrime dalyvavo 225 istorijos ir geografijos mokytojai iš Klaipėdos, Šilutės, Šilalės, Pagėgių rajonų ir savivaldybių.
Empirinėje dalyje nagrinėjamos istorijos ir geografijos modifikuotų ir adaptuotų programų sudarymas, jų trūkumai ir privalumai, aptariami mokytojų profesinio bei psichologinio pasirengimo ugdant specialiųjų ugdymo(si) poreikių vaikus, klausimai.
Svarbiausios empirinio tyrimo išvados:
1. Tyrimo duomenys, susiję su antro uždavinio sprendimu atskleidė, kad mokytojai dar ne visiškai pasiruošę rengti istorijos ir geografijos modifikuotas ir adaptuotas programas: daugiau... [toliau žr. visą tekstą] / Theoretically special educational didactical conception of problematically questioning, individual and differential educational aspects at comprehensive school analysis were done at work. Knowledge of career, preparing modified and adaptive programs of History and Geography , modified and adaptive programs, their advantages and disadvantages analysis.
Hypothesis was suggested: all preparations of modified and adaptive programs of History and Geography, their disadvantages and advantages depend on didactic and psychological preparation of pedagogues . Testing was done, which had one main purpose - to find modified and adaptive programs merits and demerits, what kind of knowledge, competence and practical skills are miss pedagogues teaching special need students and if pedagogues are ready to prepare modified and adaptive programs. Statistical methods were used to make testing.
About 225 History and geography pedagogues from Klaipėda, Šilute, Šilalė, Pagėgių districts took part in this testing.
Modified and adaptive programs of History and Geography, their formation, merits and demerits, professional and psychological preparation of pedagogues, teaching special need students, other questions analyses in empirical section.
The most important empirical conclusion:
1. Pedagogues are not ready to prepare modified and adaptive programs of History and Geography, more than half of respondents 67.0 told that they are not ready to prepare these programs , suitable ready are 24.6 and... [to full text]
|
378 |
Koreperių sluoksniuočių glodūs tęsiniai / Co-frame Bundle Smooth ExtensionMarkevičienė, Laura 20 June 2005 (has links)
In this work is analyzed a co-frame bundle first differential extension . Received local co-ordinates transformation law of the space, constructed this space linear connection and linear co-connection. In this work is proved basis space linear connection‘s object inducts objects linear connection and linear co-connection in space. Founded inducted connection curvature tensors.
|
379 |
4 klasės moksleivių elgsenos ir emocijų problemų sklaida / The expression of behavioral and emotional problems in 4 th formersKelpšienė, Inga 18 June 2008 (has links)
Problemos aktualumas:
Jaunesniame mokykliniame amžiuje (I-IV kl.) formuojasi nauji, svarbūs vaiko psichikos bruožai, kurių pagrindu ugdosi labai svarbios savybės ¬ savistaba, s¬ugebėjimas analizuoti savo poelgius ir kt. sudaro sąlygas formuotis valingam dėmesiui. Tačiau pastaruoju metu aktualia problema tampa auganti karta, kurioje yra nemažai vaikų, turinčių emocinių ir elgesio sutrikimų, kurie turi neigiamą reikšmę vaiko tolesnei psichikos raidai. Apžvelgiant kokybinių mokslinių tyrimų publikacijas Lietuvoje pasigendama mokslinių darbų, kuriuose emocijų ir elgesio problemos būtų tirtos taikant objektyvias standartizuotas metodikas. Dažniausiai duomenys renkami taikant anketavimo metodą, kurio autoriai būna patys tyrėjai. Šiuo metu užsienio šalyse emocijų ir elgesio sutrikimams vertinti plačiai naudojama BASC-2 metodika (Behavior Assessment System for Children, Reynolds ir Kamphaus, 2004, 2005), kuria galima nustatyti vaikų asmenų emocijų, jausmų ir elgesio modelių (pozityvaus ir klinikinio) ypatumus.
Tyrimo objektas – 4 kl. mokinių elgsenos ir emocijų problemos.
Tyrimo tikslas: Ištirti 4 kl. mokinių savo elgsenos ir emocijų problemų vertinimą ir palyginti jį su auklėtojos įvertinimu.
Uždaviniai:
1. Ištirti ir palyginti 4 kl. mokinių internalių ir eksternalių problemų vertinimą mokinių ir mokytojo požiūriu.
2. Išanalizuoti ir palyginti mokinių problemų mokykloje patiriamus sunkumus jų pačių ir mokytojo vertinimu.
3. Ištirti ir palyginti mokinių asmeninio prisitaikymo... [toliau žr. visą tekstą] / Topicality of the problem:
At the primary – school age (I – IV forms) new important formatives of a childs mentality start farming. They are basic for developing such important qualities as self – observation, ability to analyze ones actions and others that help to maintain volitional attention. However a new generation has recently become an urgent problem because there are a lot of children with behavioral and emotional disorders and that has negative influence on the further development of mentality. After surveying the publications of scientific studies in Lithuania it can be stated that there are no studies in which emotional and behavioral problems would be analyzed using objective standardized methods. The data is usually collected using questionnaire method the investigators themselves. At present BASC – 2 methodic (Behavior Assessment System for Children, Reynolds and Kamhaus, 2004, 2005), which makes it possible to establish peculiarities of models (positive and clinical) of childrens emotions, feelings and behavior is being widely used in foreign countries for estimation emotional and behavioral disorders.
The object of the study – emotional and behavioral problems in 4 th formers.
The aim of the study: To examine the 4 th formers estimation of their behavior and emotions and to compare it with the class – teachers estimation.
The tasks:
1. To examine and compare the estimation of the 4 th formers internal and external problems both, in their own and their teacher... [to full text]
|
380 |
Ignalinos AE tikimybinio saugos vertinimo modelio neapibrėžtumo ir jautrumo analizė / Uncertainty and sensitivity analysis of Ignalina NPP probabilistic safety assessment modelBucevičius, Nerijus 19 June 2008 (has links)
Neapibrėžtumo analizė techninių sistemų modeliavimo rezultatams yra ypač aktuali, kai modeliuojamas pavojingų sistemų darbas, saugą užtikrinančių sistemų funkcionavimas, nagrinėjami avarijų scenarijai ar kiti, su rizika susiję klausimai. Tokiais atvejais, ypatingai reaktorių saugos analizės srityje, yra labai svarbu, kad gauti modeliavimo rezultatais būtų robastiški. Šiame darbe yra atliekama Ignalinos AE tikimybinio saugos vertinimo modelio neapibrėžtumo ir jautrumo analizė. Neapibrėžtumo ir jautrumo analizė atlikta naudojantis skirtingais statistinio vertinimo metodais, taikant programų paketą SUSA. Gauti rezultatai palyginti su tikimybinio modeliavimo sistemos Risk Spectrum PSA tyrimo rezultatais. Palyginimas parodė, jog skirtingais metodais ir programiniais paketais parametrų reikšmingumas įvertintas vienodai. Statistinė neapibrėžtumo ir jautrumo analizė, taikant Monte Karlo modeliavimo metodą, leido nustatyti parametrus turėjusius didžiausią įtaką modelio rezultatui. / The uncertainty estimation is the part of full analysis for modelling of safety system functioning in case of the accident, for risk estimation and for making the risk-based decision. In this paper the uncertainty and sensitivity analysis of Ignalina NPP probabilistic safety assessment model was performed using SUSA software package. The results were compared with the results, performed using software package Risk Spectrumm PSA. Statistical analysis of uncertainty and sensitivity allows to estimate the influence of parameters on the calculation results and find those modelling parameters that have the largest impact on the result. Conclusions about for importance of a parameters and sensitivity of the result are obtained using a linear approximation of the model under analysis.
|
Page generated in 0.042 seconds