Coherent Stranski-Krastanov growth in 1+1 dimensions with anharmonic interactions: An equilibrium study

The formation of coherently strained three-dimensional (3D) islands on top of the wetting layer in the Stranski-Krastanov mode of growth is considered in a model in 1 + 1 dimensions accounting for the anharmonicity and nonconvexity of the real interatomic forces. It is shown that coherent 3D islands can be expected to form in compressed rather than expanded overlayers beyond a critical lattice misfit. In expanded overlayers the classical Stranski-Krastanov growth is expected to occur because the misfit dislocations can become energetically favored at smaller island sizes. The thermodynamic reason for coherent 3D islanding is incomplete wetting owing to the weaker adhesion of the edge atoms. Monolayer height islands with a critical size appear as necessary precursors of the 3D islands. This explains the experimentally observed narrow size distribution of the 3D islands. The 2D-3D transformation takes place by consecutive rearrangements of mono- to bilayer, bi- to trilayer islands, etc., after the corresponding critical sizes have been exceeded. The rearrangements are initiated by nucleation events, each one needing to overcome a lower energetic barrier than the one before. The model is in good qualitative agreement with available experimental observations.

Multifractal dimension of chaotic attractors in a driven semiconductor superlattice

The multifractal dimension of chaotic attractors has been studied in a weakly coupled superlattice driven by an incommensurate sinusoidal voltage as a function of the driving voltage amplitude. The derived multifractal dimension for the observed bifurcation sequence shows different characteristics for chaotic, quasiperiodic, and frequency-locked attractors. In the chaotic regime, strange attractors are observed. Even in the quasiperiodic regime, attractors with a certain degree of strangeness may exist. From the observed multifractal dimensions, the deterministic nature of the chaotic oscillations is clearly identified.

Structural, electrical and electrochemical characterization of high frequency magnetron sputtered spinel oxide cathode films for lithium ion battery applications

The main challenges in the deposition of cathode materials in thin film form are the reproduction of stoichiometry close to the bulk material and attaining higher rates of deposition and excellent crystallinity at comparatively lower annealing temperatures. There are several methods available to develop stoichiometric thin film cathode materials including pulsed laser deposition; plasma enhanced chemical vapor deposition, electron beam evaporation, electrostatic spray deposition and RF magnetron sputtering. Among them the most versatile method is the sputtering technique, owing to its suitability for micro-fabricating the thin film batteries directly on chips in any shape or size, and on flexible substrates, with good capacity and cycle life. The main drawback of the conventional sputtering technique using RF frequency of 13.56MHz is its lower rate of deposition, compared to other deposition techniques A typical cathode layer for a thin film battery requires a thickness around one micron. To deposit such thick layers using convention RF sputtering, longer time of deposition is required, since the deposition rate is very low, which is typically 10-20 Å/min. This makes the conventional RF sputtering technique a less viable option for mass production in an economical way. There exists a host of theoretical and experimental evidences and results that higher excitation frequency can be efficiently used to deposit good quality films at higher deposition rates with glow discharge plasma. The effect of frequencies higher than the conventional one (13.56MHz) on the RF magnetron sputtering process has not been subjected to detailed investigations. Attempts have been made in the present work, to sputter deposit spinel oxide cathode films, using high frequency RF excitation source. Most importantly, the major challenge faced by the thin film battery based on the LiMn2O4 cathode material is the poor capacity retention during charge discharge cycling. The major causes for the capacity fading reported in LiMn2O4cathode materials are due to, Jahn-Teller distortion, Mn2+ dissolution into the electrolyte and oxygen loss in cathode material during cycling. The work discussed in this thesis is an attempt on overcoming the above said challenges and developing a high capacity thin film cathode material.

Environmental Influences on the Frequency and Intensity of North Indian Ocean Tropical Cyclones

Tropical cyclones genesis, movement and intensification are highly dependent on its environment both oceanic and atmospheric. This thesis has made a detailed study on the environmental factors related to tropical cyclones of North Indian Ocean basin. This ocean basin has produced only 6% of the global tropical cyclones annually but it has caused maximum loss of human life associated with the strong winds, heavy rain and particularly storm surges that accompany severe cyclones as they strike the heavily populated coastal areas. Atmospheric factors studied in the thesis are the moisture content of the atmosphere, instability of the atmosphere that produces thunderstorms which are the main source of energy for the tropical cyclone, vertical wind shear to which cyclones are highly sensitive and the Sub-Tropical westerly Jetsteram and its Asian high speed center. The oceanic parameters studied are sea surface temperature and heat storage in the top layer of the ocean. A major portion of the thesis has dealt with the three temporal variabilities of tropical cyclone frequency namely intra-seasonal (mainly the influence of Madden Julian Oscillation), inter- annual (the relation with El Nino Southern Oscillation) and decadal variabilities. Regarding decadal variability, a prominent four decade oscillation in the frequency of both tropical cyclones and monsoon depressions unique to the Indian Ocean basin has been brought out. The thesis consists of 9 chapters.

Socio-Economic Dimensions of Health Care Development Among Tribals in Kerala: A Study of Tribal Communities in Wynad

The contemporary explanations and discussions of the relationship between medicine and health, and society centre around assumptions that can be broadly classified into three setsl. The first set considers health and illness as predominantly ‘biological’ and therefore, having nothing to do with the social and economic environment in which it occurs. The struggle to combat illness therefore, lies entirely within the purview of modern medicine which is neutral to economic or social change. The second considers practice of medicine as a natural science. It allows the doctor to separate himself from his subject matter, the patient, in the samelway as the natural scientist is assumed to separate himself from his subject matter, the natural world. As a 'science' and with the scientific method, it can produce unchallengable and autonomous body of knowledge which is free from the wider social and economic context. The third, different from the above, recognises the relationship between health, medicine and society. Social and environmental aspects as determinants of illness or of health comes to sharp focus here and it assigns to medicine the status of a mediator, the only viable mediator, between people and diseases. In this scheme of things the usefulness of medicine is unquestionable but the problem lies in not having enough of it to go arounds.

Dose/frequency: A critical factor in the administration of glucan as immunostimulant to Indian white shrimp Fenneropenaeus indicus

The immunostimulatory effect of an alkali insoluble glucan extracted from marine yeast isolate Candida sake S165 was tested in Fenneropenaeus indicus. Post larvae (PL) of F. indicus, fed glucan incorporated diet at varying concentrations (0.05, 0.1, 0.2, 0.3, 0.4 g glucan/100 g feed) for 21 days were challenged orally with white spot syndrome virus (WSSV). Maximum survival was observed in PL fed the 0.2% glucan incorporated diet. Subsequently the feed incorporated with 0.2% glucan was fed to F. indicus post larvae at different feeding intervals, i.e. daily, once every two days, once every five days, once every seven days and once every ten days. After 40 days, the prawns were challenged orally with WSSV and post challenge survival was recorded. Shrimp feed containing 0.2% glucan when administered once every seven days gave maximum survival. This was supported by haematological data obtained from adult F. indicus, i.e. total haemocyte count, phenoloxidase activity and nitroblue tetrazolium reduction (NBT). The present observation confirms the importance of dose and frequency of administration of immunostimulants in shrimp health management

Frequency Coded Chipless RFID Tag using Spurline Resonators

A novel compact chipless RFID tag using spurline resonators is discussed in this paper. The detection of the tag's ID is using the spectral signature of a spurline resonator circuit. The tag has a data capacity of 8-bits in the range 2.38 to 4.04 GHz. The tag consists of a spurline multiresonating circuit and two cross polarized antennas. The prototype of the tag is fabricated on a substrate CMET/ LK4.3 of dielectric constant 4.3 and loss tangent 0.0018. The measured results show that group delay response can also be used to decode the tag’s identity

Determination of charge carrier transport in radio frequency plasma polymerized aniline thin films

The carrier transport mechanism of polyaniline (PA) thin films prepared by radio frequency plasma polymerization is described in this paper. The mechanism of electrical conduction and carrier mobility of PA thin films for different temperatures were examined using the aluminium–PA–aluminium (Al–PA–Al) structure. It is found that the mechanism of carrier transport in these thin films is space charge limited conduction. J –V studies on an asymmetric electrode configuration using indium tin oxide (ITO) as the base electrode and Al as the upper electrode (ITO–PA–Al structure) show a diode-like behaviour with a considerable rectification ratio

Comments on Simple and Accurate Formula for the Resonant Frequency of the Equilateral Triangular Microstrip Patch Antenna

Antennas and Propagation, IEEE Transactions on,VOL 48,issue 4,pp 636

SUBKAVYA: KATHYA KE VIBHINNA AYAM (POETRY OF SURDAS-DIFFERENT DIMENSIONS OF POETIC CONTENT)

HINDI

THE CHANGING DIMENSIONS or SOCIAL c0NsI0usNEss IN THE REPRESENTATIVE NOVELS or SEVENTIES

Hindi

DIMENSIONS OF CULTURAL CRISIS IN CONTEMPORARY HINDI POETRY

Hindi

Influence of Frequent Flyer Programme and Airline Service Quality on Re-buy Intentions of Airline Frequent Passengers

The growth potential of service sector, especially the aviation sector in the Indian economy is splendid. Therefore, it is crucial for the airline service providers to realize their customers, design offers and deliver the desired value to their customers. This study reveals the effect of airline passenger satisfactions particularly on re-buy intentions derived from the attributes-level performance dimensions of both service aspects and loyalty programme of an airline. The mediation effect of satisfaction and other selected antecedents on the re-buy intention of a passenger is hypothesized in this study. Critical areas affecting buying intentions such as core service quality and loyalty attribute-level performances, effect of frequent flyer programme and service quality satisfaction, passenger trust on airline, brand image and moderating effects of perceived value, frequent programme status and travel frequency of airline passengers are linked in a structural model to assess the strength of each facet in affecting re-buy intentions. Implications to the airlines were made based on the finding that re-buy intentions cannot be attributed solely to the impacts of frequent flyer programme, rather affected through the mediation effect of airline service quality satisfaction, which is very much valid for the higher FFP status category of frequent travelers. The effects of moderation caused by perceived value, FFP status and flying experience were also found to be significant in making re-buy intentions.

Effect of market-driven minigrids on the frequency stabilization process of isolated middle-sized power grids

Neueste Entwicklungen in Technologien für dezentrale Energieversorgungsstrukturen, erneuerbare Energien, Großhandelsenergiemarkt, Mini- und Mikronetze, verteilte Intelligenz, sowie Informations- und Datenübertragungstechnologien werden die zukünftige Energiewelt maßgeblich bestimmen. Die derzeitigen Forschungsbemühungen zur Vernutzung aller dieser Technologien bilden die Voraussetzungen für ein zukünftiges, intelligentes Stromnetz. Dieses neue Konzept gründet sich auf die folgenden Säulen: Die Versorgung erfolgt durch dezentrale Erzeugungsanlagen und nicht mehr durch große zentrale Erzeuger; die Steuerung beeinflusst nicht mehr allein die Versorgung sondern ermöglich eine auch aktive Führung des Bedarf; die Eingabeparameter des Systems sind nicht mehr nur mechanische oder elektrische Kenngrößen sondern auch Preissignale; die erneuerbaren Energieträger sind nicht mehr nur angeschlossen, sondern voll ins Energienetz integriert. Die vorgelegte Arbeit fügt sich in dieses neue Konzept des intelligenten Stromnetz ein. Da das zukünftige Stromnetz dezentral konfiguriert sein wird, ist eine Übergangsphase notwendig. Dieser Übergang benötigt Technologien, die alle diese neue Konzepte in die derzeitigen Stromnetze integrieren können. Diese Arbeit beweist, dass ein Mininetz in einem Netzabschnitt mittlerer Größe als netzschützende Element wirken kann. Hierfür wurde ein neues Energiemanagementsystem für Mininetze – das CMS (englisch: Cluster Management System) – entwickelt. Diese CMS funktioniert als eine von ökonomischorientierte Betriebsoptimierung und wirkt wie eine intelligente Last auf das System ein, reagierend auf Preissignale. Sobald wird durch eine Frequenzsenkung eine Überlastung des Systems bemerkt, ändert das Mininetz sein Verhalten und regelt seine Belastung, um die Stabilisierung des Hauptnetzes zu unterstützen. Die Wirksamkeit und die Realisierbarkeit des einwickelten Konzept wurde mit Hilfe von Simulationen und erfolgreichen Laborversuchen bewiesen.

Kompetenzraster aus dem schweizerischen Institut Beatenberg - eine Option für berufliche Schulen in Deutschland?

Der Name einer kleinen Internatsschule im Berner Oberland taucht zunehmend in den Diskussionen über die Gestaltung von selbst organisiertem Lernen auf: Institut Beatenberg. Der Direktor des Instituts, Andreas Müller, und seine Mitarbeiter sind gefragte Referenten auf Veranstaltungen über die Einführung einer Lehr-Lernkultur, die den Lernenden und seine Lernprozesse in den Mittelpunkt der pädagogischen Arbeit stellt. Zudem finden ihre Publikationen zunehmendes Interesse im gesamten deutschsprachigen Raum. Ein Schlüsselinstrument wurde dabei zum Schlagwort: Kompetenzraster. Doch die stellen nur eines der Instrumente dar, die den ‚Wirkungskreislauf des Lernerfolgs’ in Beatenberg stützen. Berufliche Schulen in Hessen und Hamburg haben im Rahmen von Modellprojekten mit der Erarbeitung von Kompetenzrastern nach den Vorbildern in Beatenberg begonnen und versprechen sich damit eine neue, auf selbst organisiertem Lernen aufbauende kompetenzorientierte berufliche Bildung. In dem Beitrag werden die Arbeit mit Kompetenzrastern und den dahinter liegenden ‚Lernlandschaften’ sowie der ‚Wirkungskreislauf den Lernerfolgs’ in Beatenberg kompetenzorientiert dargestellt. Die Dimensionen Definition, Beschreibung, Ordnung, Erwerb, Messung und Anerkennung von Kompetenzen werden herausgearbeitet und die Möglichkeiten von Kompetenzrastern in der beruflichen Bildung kritisch gewürdigt. Der Beitrag ist entlang der genannten Dimensionen gegliedert.