• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 94
  • 40
  • 17
  • 17
  • 14
  • 12
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 244
  • 41
  • 39
  • 31
  • 29
  • 26
  • 23
  • 23
  • 18
  • 16
  • 15
  • 14
  • 14
  • 14
  • 14
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Process Management and Fast Context Switch for MinixARM

Gu, Jin-Hua 27 June 2007 (has links)
MINIX is a tiny OS kernel originally for teaching purpose. The well known presently popular OS, Linux, is extended from right this OS kernel of MINIX. The most valuable one of MINIX feature is the application for embedded system. Nowadays the development of SOC is full of vitality and it might someday integrate the MINIX with creative application. SOC is shorten from System On Chip. It implies that hardware cannot hold without a system so studying, developing and broadcasting the design of a fine and simple system is as important as designing a mature hardware. MINIX has well designed architecture and can be elastically extended for any application if anything is wanted to carry out. But orginal MINIX is only designed for INTEL x86 CPU. It should be more extensively extended to more environments. ARM is nowadays popular CPU on the world and this gives our a worthy studying to port MINIX to ARM. Surely during and after porting we found a lot of circumstances that can help and give other evelopers useful information and methods to carry on farther studying and improvement.
2

Kliniska riktlinjer i teori och praktik : En studie vid Sahlgrenska Universitetssjukhuset

Grönvall, Emma January 2011 (has links)
No description available.
3

Introducing integrated performance measurement into small and medium sized enterprises

Hudson, Melanie January 2001 (has links)
The thesis extends current knowledge and understanding of integrated performance measurement (PM) development into the context of small and medium sized enterprises (SMEs). The research builds on existing knowledge of integrated PM development approaches and identifies the context-specific factors which affect its introduction into SMEs. These are used to design, develop and validate a new, continuous improvement based approach for the development of integrated PM systems, which is specifically designed for use in SMEs. First, a conceptual model of criteria for integrated PM development is synthesised from the literature and the characteristics of SMEs are established. An evaluation of current approaches for the development of integrated PM is undertaken and an approach which conforms to the conceptual model is selected for an empirical study in a SME. Along with a set of interviews examining the state of PM in SMEs, this study identifies several factors which affect integrated PM introduction in this environment. These factors enhance the conceptual model and indicate the need for a more effective development approach for SMEs. Design theory is used to inform and structure the design of the new approach, which is developed and refined for practical use through a SME case study. Two further cases are carried out to validate the new approach, in which cross-case comparisons are made. The results indicate the validity of both the new approach and the enhanced conceptual model. The formulation of an enhanced conceptual model of integrated PM development, detailing the context specific criteria for effective in use in SMEs, together with the validation of a new, continuous improvement based, approach for integrated PM system development in SMEs that conforms to the conceptual model, represents a significant contribution to both theory and practice from this research.
4

Evaluation of Airborne Particles at a Local High School

Klender, Stephanie 20 August 2014 (has links)
No description available.
5

Performance Analysis of CPSK Transimission through Nonlinear Channels

Hetrakul, Priti 03 1900 (has links)
<p>Virtually all satellite repeaters use a traveling-wave tube (TWT) as their main power amplifier. Because on-board power is a limited commodity, it is highly desirable that the TWT be operated as efficiently as possible, namely in or near saturation where it is highly nonlinear. These nonlinear effects manifest themselves as an amplitude compression (AM/AM conversion) effect and an amplitude dependent phase modulation (AM/PM conversion) effect. In this thesis a number of investigations have been made in relation to the TWT nonlinearities and their effect on the performance of communication systems.</p> <p>A novel quadrature model of the TWT has been developed. This model is most useful in that it is analytic and requires the choice of only four parameters to obtain an excellent fit to the TWT characteristics.</p> <p>An optimal bandpass nonlinear transfer characteristic that maximizes its output signal to interference power ratio has also been derived. By making use of this optimal transfer characteristic and the quadrature model of the tube, a computer-aided design procedure has been described for obtaining a predistortion compensation network for the TWT. This network consists of a simple arrangement of attenuators and power-law devices and has been shown, by computer simulation, to yield about 1 dB improvement in system performance for the case when only a single carrier is present in the TWT.</p> <p>In the case when a single sample detection and majority logic decision circuit is assumed at the receiver, it has been possible to derive analytical expression for the probability of error of M-ary CPSK signals transmitted through a piecewise-linear envelope limiting repeater. An infinite series expression for the bit error rate of binary CPSK transmission through an actual TWT channel has also been derived.</p> <p>A performance analysis of a correlation receiver with a linear integrate and dump circuit has been carried out for the case of binary CPSK transmission through a bandpass nonlinearity exhibiting AM/PM conversion.</p> <p>For the case of purely amplitude-limiting channels, an optimal (maximum-likelihood) receiver structure and its approximate performance has also been investigated.</p> / Thesis / Doctor of Philosophy (PhD)
6

Microstructure and mechanical properties of sintered (2-4)Mn-(0·6-0·8)C steels

Cias, A., Mitchell, Stephen C., Watts, Andrew, Wronski, Andrew S. January 1999 (has links)
Yes / Mechanical properties of 2-4% manganese PM steels were determined in tension and in bending following laboratory sintering in dry, hydrogen rich atmospheres. Young's modulus determined by an extensometric technique was about 115 GPa; when measured by an ultrasonic method it was about 153 GPa, in accordance with the 'law of mixtures'. The microstructures, significantly devoid of oxide networks, were predominantly pearlitic, but frequently with variability for specimens similarly processed, resulting in appreciable variations in the stresses for macroscopic yielding and fracture. The majority of the experiments were conducted on 3 and 4Mn-0·6C alloys and for these R0·1 was in the range 275-500 MPa, tensile strength (TS) 300-600 MPa, and (apparent) transverse rupture strength (TRS) 640-1260 MPa. Statistical techniques were employed to analyse the data. When careful control of processing was maintained, the Weibull modulus was highest, at about 17, for TS of furnace cooled specimens, and lowest, about 6, for TRS of the rapidly cooled specimens. In order to interpret the significant differences between the TRS and the TS values, both apparently measuring the critical stress for cracking after strains of up to 7%, a two stage normalising technique for TRS was adopted. By taking account of the plastic strains preceding failure, the elastic 'strength of materials' formula was modified to allow true fracture stresses to be calculated. It was also postulated that failure was initiated from a population of flaws of variable size and then the 'normalised' bend strengths, smaller than TRSs, were shown to correspond well with TSs. It is suggested that this combined plasticity correction and Weibull analysis approach, which has a sound scientific basis, should be employed to interpret bend test data in preference to empirical correlations between TS and TRS.
7

"The home and the world" : representations of English and bhashas in contemporary Indian culture

Cowaloosur, Vedita January 2013 (has links)
Although they have cohabited in India for centuries, critical analyses of contemporary Indian literature and culture often seem to draw a distinction between the "world" of the English language and that of the bhashas (or Indian regional languages) — as though the two are sealed off from each other with no conceivable overlaps. Even sixty-six years after independence, the debate over the contested linguistic terrains of "home" and "world" - and whether these seeming dichotomies are mappable as "Indian"/"non-Indian” or "provincial"/"cosmopolitan" — continue. Through a study of contemporary and modern Indian literary and cultural discourses, I analyse the historical and ideological roles played by English language — the ways in which it has interacted with bhashas, and the importance of the literary representation of English and bhashas in the politics of Indian cultural and linguistic nationalism(s). Along with canonical Indian English writing (such as the works of Vikram Seth, Amitav Ghosh and Salman Rushdie) I analyse bhasha literature (especially Hindi, Bengali and Urdu) as well as Indian literature in translation as my primary texts. My study includes fiction, as well as political documents and life writing (notably those by M. K. Gandhi and Jawaharlal Nehru). The analysis of Hindi cinema, ranging from films like Mughal-e-Azam (1960) to Ra.One (2011) remains a running thread throughout, for this popular medium encapsulates the Indian linguistic debates in a way that is sometimes complementary and at other times a foil to the literary cultural discourse. In each of my chapters I analyse the mobilisation of language(s) in relation to one of the categories that, in India’s charged socio-political setting, become associated with the question of one’s communal, cultural and/or territorial “identity” — namely nation, religion, and caste and class. Though this is a thesis about language and its cultural representation in postcolonial India, I often flit to events in pre-1947 India in the course of my discussions. This is because some of the cultural moments from the colonial past are either historical precedents to, or prove to be momentous departures from, the events that I focus on in contemporary India. Their significance can therefore not be ignored in any comprehensible analysis of the roles that language has played in India after independence.
8

Investigating effects of hypertonic saline solutions on lipid monolayers at the air-water interface

Nava Ocampo, Maria F. 05 1900 (has links)
More than 70,000 people worldwide suffer from cystic fibrosis, a genetic disease characterized by chronic accumulation of mucus in patients’ lungs provoking bacterial infections, and leading to respiratory failure. An employed age-old treatment to prevent the symptoms of the disease is inhalation of hypertonic saline solution, NaCl at concentrations higher than in the human body (~150 mM). This procedure clears the mucus in the lungs, bringing relief to the patient. However, the biophysical mechanisms underlying this process are not entirely clear. We undertook a new experimental approach to understand the effects of sprayed saline solutions on model lung surfactants towards understanding the mechanisms of the treatment. The surface of lungs contains mainly 1,2-Dipalmitol-sn-glycero-3-phosphocoline (DPPC). As previously assumed by others, we considered that monolayer of DPPC at the air-water interface serves as model system for the lungs surface; we employed a Langmuir-Blodgett (LB) trough and PM-IRRAS to measure surface-specific infrared spectra of the surfactant monolayers and effects on the interfacial tensions. We investigated spraying hyper-saline solutions onto surfactant monolayers at the airwater interface in two parts: (i) validation of our methodology and techniques with stearic acid and (ii) experiments with DPPC monolayers at the air-water interface. Remarkably, when micro-droplets of NaCl were sprayed to the monolayer of stearic acid, we observed enhanced organization of the surfactant, interpreted from the intensities of the CH2 peaks in the surface-specific IR spectra. However, our results with DPPC monolayers didn’t show an effect with the salt added as aerosol, possibly indicating that the experimental methodology proposed is not adequate for the phenomena studied. In parallel, we mimicked respiratory mucous by preparing salt solutions containing 1% (wt%) agar and measured effects on their viscosities. Interestingly, we found that NaCl was much more effective than NaI and NaClO4. This thesis reports structural dynamics of monolayers of stearic acid and DPPC at the airwater interfaces and those of aqueous solutions towards understanding mechanisms underlying the most commonly employed treatment for cystic fibrosis. Our methodology has never been reported before; but requires further modifications to gain deeper insights into the effects of salt sprays on model lung systems.
9

Surface Chemistry and Spectroscopic Studies of the Peptidolipids and Proteins Langmuir Monolayer

Wang, Chengshan 17 April 2008 (has links)
It was found that there was a specific interaction between peptidolipid C18H35O (Stearoyl)-Phe-Trp-Ser-His-Glu and paraoxon. The aromatic residue groups were involved in the recognition between paraoxon and the peptidolipid, because the fluorescence of Trp in the peptidolipid at 351 nm was quenched by paraoxon in the subphase. When paraoxon was dissolved in the subphase, the surface potential-area (delta V-A) isotherm for the peptidolipid A displayed an unusual shape. This was interpreted on the basis of Infrared Reflection-Absorption Spectroscopy (IRRAS) results as being due to the reorientation of the benzene ring of paraoxon, which changed from parallel to the air-water interface in the absence of a monolayer to a tilted orientation upon interacting with the peptidolipid Langmuir monolayer. The secondary structure of oganophosphorus acid anhydrolase (OPAA) Langmuir monolayer in the absence and presence of diisopropylfluorophosphate (DFP) in the subphase was also studied by the IRRAS and Polarization Modulated-IRRAS (PM-IRRAS). The shape of OPAA molecules is supposed to be elliptic and the long axis of OPAA was parallel to the air-water interface in the absence of DFP in the subphase, whereas the long axis became perpendicular in the presence of DFP. This result explains the decrease of the limiting molecular area of OPAA Langmuir monolayer when DFP was dissolved in the subphase. Using the Langmuir monolayer technique, the surface properties of aequorin were studied. The results showed that aequorin formed a stable Langmuir monolayer and the surface pressure-area isotherms were dependent on both pH and ionic strength. At a pH higher or lower than 7.6, the limiting molecular area decreased. The addition of calcium chloride to the Tris/HCl buffer subphase (pH 7.6) caused an increase of the limiting molecular area of the aequorin Langmuir monolayer. The fluorescence spectra of a Langmuir-Blodgett (LB) monolayer of aequorin in the presence of calcium chloride indicated that the aequorin transformed to the apoaequorin. The Langmuir monolayer of aequorin and apoaequorin was studied by IRRAS and PM-IRRAS techniques. The different behavior of aequorin and apoaequorin at the air-water interface was explained by the fact that aequorin formed dimers at air-water interface but apoaequorin was monomer. It was more difficult for a dimer to be tilted by the compression of the Langmuir monolayer.
10

Modeling and Analysis of a Surface Permanent Magnet Machine

Lin, Ming-Han 17 January 2007 (has links)
The objective of this thesis is to provide the systematic design procedure for a high-speed PM motor with portable sizes, along with the detailed mathematical model developments and the thorough operational analysis. The entire scheme is realized by first following an available design reference to estimate the desired machine physical structures. Then, based on the related field theory, recoil line characteristics of permanent magnets, and the magnetic equivalent circuit method, the system mathematical model can be devised. Finally, the system operational behaviors can be investigated by the devised analytical models, and their accuracies will also be confirmed by the reference design tool. It is believed that the proposed design and verification scheme can provide a valuable and reasonable guidance for the related industry application.

Page generated in 0.0145 seconds