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  • 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.
11

Systemdynamische Analyse des Serienanlaufs in der Automobilindustrie

Jürging, Jan January 2007 (has links)
Zugl.: Mannheim, Univ., Diss., 2007
12

For the children?: an inquiry into the purpose and evaluation of Head Start

Caruso, Margret January 1994 (has links)
Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02
13

The Effects of Increased Ignition Energy on Cold Start Hydrocarbon Emissions

Slaughter, Raymond L. Jr. 28 September 1998 (has links)
A study on the effects of increased ignition energy on cold start hydrocarbon emissions was conducted. The tests were conducted on a single cylinder ASTM-CFR engine. The engine was outfitted with EFI, exhaust analyzers, and temperature probes. The engine was also modified to produce cold start conditions rapidly after each run. For the experiment the engine was started from 18° C using three increasing ignition energy levels. The first level of ignition energy was the ignition energy produced by the stock CFR engine's ignition system. The second and third increased ignition energy levels were obtained by adding 0.387 joules and 1.187 joules to the stock output through a supplementary ignition system. Startup emissions and the number of cycles until the first successful fire were measured. The results of the tests show a 14% decrease in the average peak hydrocarbon (HC) concentration levels at the highest ignition energy. Overall reduction in HC was less. The variance in the peak HC levels was reduced at the highest ignition energy setting. CO production was increased in response to the increase in HC consumption. The spread in measured number of cycles until first fire was decreased at the highest ignition energy level. Although positive results were obtained, the test apparatus had some problem areas that may have reduced the effectiveness of the high energy ignition system. Based on what was learned recommendations on apparatus refinements and further tests were included. / Master of Science
14

An analysis of changes in ranking equality by Tennessee Head Start staff /

Griesemer, Marilyn Stauf January 1979 (has links)
No description available.
15

Starty sprinterských disciplín spastické atletky a specifika tréninkového procesu / Starts of sprint disciplines performed by spastic athlete and particularities of the training process

Šteklová, Petra January 2016 (has links)
Title: Starts of sprint disciplines performed by spastic athlete and particularities of the training process Aim of work: The aim of this work was analyzing of the specifics of athletic training determined for spastic sprinter class T38 and observation of the long term effect. Methods: This work presents an empiric-theoretical study. Due to the uniqueness of the theme, method of case study has been chosen (intra-individual observation). This method was applied on the particular spastic sprinter by using longitudinal quantitative observation during her top sport career and applying one-off analysis focused on evaluation of different types of starts. This observation had qualitative and quantitative part. The quantitative part was based on the interpretation of 2D video comparing three types of start (low start, mid-low start and low start with a diagonal arm position) with the optimal start position described in the books. Comparison of average time for 10 metre distance was determined as quantitative element. . The observational group consists of the sprinter with Cerebral Palsy at Czech representative level. Results: Our research resulted as follows: The mid-low start was assessed as the best one for the examined sprinter from the quality of start position point of view including the three...
16

Starty sprinterských disciplín spastické atletky a specifika tréninkového procesu / Starts of sprint disciplines performed by spastic athlete and particularities of the training process

Šteklová, Petra January 2016 (has links)
Title: Starts of sprint disciplines performed by spastic athlete and particularities of the training process Aim of work: The aim of this work was analyzing of the specifics of athletic training determined for spastic sprinter class T38 and observation of the long term effect. Methods: This work presents an empiric-theoretical study. Due to the uniqueness of the theme, method of case study has been chosen (intra-individual observation). This method was applied on the particular spastic sprinter by using longitudinal quantitative observation during her top sport career and applying one-off analysis focused on evaluation of different types of starts. This observation had qualitative and quantitative part. The quantitative part was based on the interpretation of 2D video comparing three types of start (low start, mid-low start and low start with a diagonal arm position) with the optimal start position described in the books. Comparison of average time for 10 metre distance was determined as quantitative element. . The observational group consists of the sprinter with Cerebral Palsy at Czech representative level. Results: Our research resulted as follows: The mid-low start was assessed as the best one for the examined sprinter from the quality of start position point of view including the three...
17

A Comparison of Written Compositions of Head-Start Pupils With Non-Head-Start Pupils

Houston, David Ree 08 1900 (has links)
The problem of this study was to compare the written language development of two groups of disadvantaged children at the end of their fourth year of school.
18

The adoption of open innovation in the start-up development process : A narrative inquiry on the mobile services industry in Sweden

Bünte, Frederick Alexander January 2015 (has links)
Start-ups face several issues and challenges in the course of their development as a compa-ny. Open innovation has been discussed in research for more than a decade as a concept, which can bring benefits to a company. Even though most of the research has been focus-ing on large enterprises, some researchers discuss also benefits for small companies like start-ups. Nevertheless, it can be observed that some start-ups decide to adopt the opposite of open innovation, namely closed innovation, through not sharing internal knowledge to the outside world. Hence, start-ups perceive the benefits of open innovation differently and decide accordingly whether to adopt open innovation or not. The purpose of this study is to explore if start-ups decide to actually do the former and what reasons they have to do so. Therefore, this study will further discover at what point in the development of their start-up and with whom they adopt open innovation. As an attractive industry for start-ups, the mobile services industry is selected as a scope for this study. Furthermore, Sweden is selected as the country of study, due to its reputation as one of the most innova-tive countries in the world. A qualitative study has been conducted using in-depth interviews with founders and co-founders of start-ups to retrieve narrative stories about their start-up’s development from the first day of an idea to a scalable business, and their experiences and motivations in re-gards to the application of open innovation practices. The analysis of this study detects pat-terns among the interviewed start-ups and concludes that start-ups in the mobile services industry in Sweden adopt open innovation in each phase of their development process. Furthermore, these patterns include several reasons why the start-ups applied open innova-tion practices and with whom, which are changing over the course of their development.
19

Performance of three start techniques off the OSB11 starting block over 15M

Reagon, lynne Veronique January 2019 (has links)
Doctor Educationis / Background: In swimming, a swimmer’s performance is mostly determined by the time spent on starts, stroking and turning. The start of a swimming races, especially sprint races, can account for almost a quarter of race time. Aim: The aim of this study was to analyse the biomechanics and performance of three start techniques off the OSB11 starting platform over 15-meters to determine which of the three is most effective when looking at the three parts that constitute the start: block time, flight time and underwater time. Methods: A Quasi-experimental cross over trial-based study design was used to determine which of three starting techniques (Grab, Track & Kick) was the most effective off the OSB11 starting block. Ten Swimmers who qualified for junior nationals from Vineyard Swimming Club participated in the study. Each participant acted as their own control and were required to perform each start once. All trials were filmed and analysed on Dartfish pro suite 10. The following variables were analysed: shoulder angle, hip angle, knee angle, reaction time, movement time, total block time, flight distance, flight time, flight velocity, entry angle, underwater time, underwater distance, time to 15-meters.
20

Dynamical evolution of idealised star cluster models

Breen, Philip Gavin January 2013 (has links)
This thesis is concerned with the dynamical evolution of globular star clusters modelled as the classical gravitational N-body problem. The models in this thesis are idealised in order to allow the detailed study of particular dynamical aspects of the cluster evolution. Examples of properties which tend to be omitted are stellar evolution, primordial binaries and the effect of an external tidal gravitational field. The methods used in this thesis are gas models, N-body models and physical arguments. One of the main topics in this thesis is gravothermal oscillations in multicomponent star clusters. The evolution of one-component globular clusters, systems with equal particle masses, is quite well understood. However, the evolution of more realistic globular clusters, with a range of particle masses, is a much more complicated matter. The condition for the on-set of gravothermal oscillations in a one-component system is simply that the number of stars is greater than a certain number ( ≈7000). In a multi-component system the relationship between the number of stars at which the gravothermal oscillations first appear and the stellar mass distribution of a cluster is a complex one. In order to investigate this phenomenon two different types of multi-component systems were studied: two-component systems (the simplest approximation of a mass spectrum, Chapter 2) and ten-component systems (which were realisations of continuous power law IMFs, Chapter 3). In both cases the critical number of stars at which gravothermal oscillations first appear are found empirically for a range of stellar mass distributions. The nature of the oscillations themselves are investigated and it is shown that the oscillations can be understood by focusing on the behaviour of the heavier stars within the cluster. A parameter Nef (de nined Mtot/mmax where Mtot is the total mass and mmax is the maximum stellar mass) acts as an approximate stability boundary for multicomponent systems.The stability boundary was found to be at Nef ~- 12000. In this Chapter 4, globular star clusters which contain a sub-system of stellar-mass black holes (BH) are investigated. This is done by considering two-component models, as these are the simplest approximation of more realistic multi-mass systems, where one component represents the BH population and the other represents all the other stars. These systems are found to undergo a long phase of evolution where the centre of the system is dominated by a BH sub-system. After mass segregation has driven most of the BH into a compact sub-system, the evolution of the BH sub-system is found to be in uenced by the cluster in which it is contained. The BH sub-system evolves in such a way as to satisfy the energy demands of the whole cluster, just as the core of a one component system must satisfies the energy demands of the whole cluster. The BH sub-system is found to exist for a significant amount of time. It takes approximately 10trh;i, where trh;i is the initial half-mass relaxation time, from the formation of the compact BH sub-system up until the time when 90% of the sub-system total mass is lost (which is of order 103 times the half-mass relaxation time of the BH sub-system at its time of formation). Based on theoretical arguments the rate of mass loss from the BH sub-system (M2) is predicted to be (βζM)/(αtrh): where M is the total mass, trh is the half-mass relaxation time, and α, β, ζ are three dimensionless parameters. (see Section 4.3 for details). An interesting consequence of this is that the rate of mass loss from the BH sub-system is approximately independent of the stellar mass ratio (m2/m1) and the total mass ratio (M2/M1) (in the range m2/m1 ≥ 10 and M2/M1 ≈ 10-2, where m1, m2 are the masses of individual low-mass and high-mass particles respectively, and M1, M2 are the corresponding total mass). The theory is found to be in reasonable agreement with most of the results of a series of N-body simulations, and all of the models if the value of ζ is suitable adjusted. Predictions based on theoretical arguments are also made about the structure of BH sub-systems. Other aspects of the evolution are also considered such as the conditions for the onset of gravothermal oscillation. The final chapter (Chapter 5) of the thesis contains some concluding comments as well as a discussion on some possible future projects, for which the results in this thesis would be useful.

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