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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.

Ganzheitliches Time-to-market-Management Planung und Umsetzung von Produktinnovationen unter besonderer Berücksichtigung des Wettbewerbsfaktors Zeit

Labriola, Fabio January 2006 (has links)
Zugl.: Freiberg (Sachsen), Techn. Univ., Diss., 2006

The engineering development of power transmission belts based on thermoplastic polyurethane elastomers

Knox, John Graeme January 2003 (has links)
No description available.

Optimisation of area traffic control for equilibrium network flows

Chiou, Suh-Wen January 1998 (has links)
No description available.

The role of pH in human sperm function

Brook, Philip Francis January 1996 (has links)
No description available.

Married Couples’ Understandings of Family Planning and their Communication Processes

Chitavi, Salome Omuyoma 14 November 2006 (has links)
Faculty of Arts 9803428v / This dissertation examines husbands and wives’ understandings of family planning and communication processes. It examines family planning approval, knowledge of contraceptives and motivations for contraceptive use by husbands and wives. The study provides insights into these variables as held by husbands and wives and implications for contraceptive use. The dissertation also provides insights into the nature of communication processes while relating this to couples’ inconsistencies noted from quantitative data, their marital and reproductive history, and contraceptive use implications. The study uses KDHS 1998 survey Western Province couples’ data set that includes 176 married couples. The study further uses data from Focus Group Discussions conducted amongst husbands and wives in Vihiga District of Western Kenya. The study notes that variables such as contraceptive knowledge, approval of family planning and spousal family planning communication continue to have inconsistent and unclear relationship with contraceptive use. The study argues that these variables are not simply related to contraceptive use and need further examination using qualitative methodologies. The culture and political-economy of fertility conceptual framework and its various aspects of levels, process, causality, time and methodology is applied in the examination of husbands and wives’ understandings of family planning and contraceptive use communication between spouses. The findings of this study reveal that family planning understandings by husbands and wives including knowledge, attitudes and motivations for contraceptive use and spousal family planning communication are related to contraceptive use yet the relationship remains complex and can be understood through examining how different contextual levels and processes enhance varied notions of these factors as held by husbands and wives in relation to contraceptive use; the timing in terms of couples’ marital and reproductive history; the various socio-cultural and politicaleconomic processes surrounding the couples and the individual agency of the husband and wife in pursuing their fertility goals. While none of these factors adequately predicts contraceptive use on their own, an examination of husbands and wives within such a framework provides a better linkage to potential for contraceptive use or lack of it at married couple level. Thus while knowledge or approval of family planning perse fails to provide a clear or consistent link to contraceptive use, the study highlights the various notions of knowledge including individual husbands’ and wives’ perceptions about own knowledge of family planning; and differences in approval ranging from widespread general approval in line with community perceptions, twin perceptions of approval and disapproval common at individual level and disapproval of family planning and the fact that these may change across reproductive histories are factors within the concepts of family planning knowledge and approval that provide better understanding for potential for contraceptive use. The study therefore provides further insights regarding how husbands and wives understand variables commonly related to family planning and varied implications for contraceptive use. With regards to communication, the study underlines that spousal family planning communication is not simply linked to contraceptive use. Instead spousal family planning communication is a complex process informed partly by husbands’ and wives’ understandings of family planning; their perceptions of own knowledge regarding contraceptive methods; their various motivations for family planning involvement and their gender based relationship and perceptions of dominance. The study highlights various forms of spousal family planning communication processes and implications for contraceptive use. This study further argues that the potential of spousal family planning communication’ complex relationship with contraceptive use is related to the nature, timing, content of the communication processes and the agency of the individual husband and wife in influencing spousal family planning communication and decision making. The thesis ends with conclusions and provides recommendations for family planning programs and future studies while highlighting limitations of this study.

A Novel Timing Estimation Method for OFDM Systems

Chen, Ping-chu 24 August 2007 (has links)
In this thesis, a novel training sequence is proposed for timing offset estimation in orthogonal frequency division multiplexing (OFDM) systems. The proposed training sequence and the derived timing offset estimator are proved to outperform traditional schemes. In timing estimation of OFDM systems, the scheme proposed by Schmidl [4,5] is perhaps the most well-known one. However, Schmidl¡¦s scheme has a plateau in timing metric, which substantially degrades system performance. In this thesis, simulation experiments are conducted to evaluate the performance of the proposed timing offset estimator and the mean square error (MSE) is adopted as the performance measure. Simulation results demonstrate that the performance of the proposed scheme not only improves Schmidl¡¦s scheme, but also outperforms Minn¡¦s [9] and Park¡¦s [10] schemes.

A Novel Timing Offset Estimation Method for OFDM Systems

Lin, Chih-yu 29 June 2005 (has links)
Orthogonal frequency division multiplexing systems are much more sensitive to timing and frequency error, therefore there were several methods to estimate time and frequency offset. In the thesis, a novel timing offset estimation method for OFDM systems is proposed, it transmits a specific training symbol in the time domain at transmitter. At the receiver, it estimate the timing offset by using a specific timing metric. The proposed scheme isn¡¦t affected by the frequency offset compare with Zhang¡¦s method, and it can estimate timing offset more accurately than Schmidl¡¦s method and Minn¡¦s method. We will analyze the statistical characteristic of the timing metric we proposed at correct time. According to the analysis and simulation result, it can show the accuracy of our analysis. Finally from the simulation result, it demonstrates that the proposed scheme has better performance.

The Relationship Between the Timing Ability and the Characteristics of Funds under the Macro-Information Factors

WEY, Tian-Yuan 12 February 2003 (has links)
Abstract According to the studies about testing the timing abilities of funds, they used only one kind of index as a benchmark to test the timing abilities of funds, but it¡¦s not fair. Each kind of funds form its owned portfolio based on its unique goals. So if we test the timing abilities of funds by using the same benchmark, we will neglect the difference between different kinds of funds. Therefore, I use three rate of return of indices (index of price of small corporations, index of price of electron industry and Y9999) as benchmarks for three kinds of funds (funds investing in small corporations, funds investing in tech-related industries, funds investing other industries). I find that testing the timing abilities of funds by using suitable index as benchmark for different funds can get more funds with significant timing abilities. Since the funds are managed by professional fund-managers, they must know how to analysis macro-information well known in public and get some helpful information to decide when to invest. In this study, I test the timing abilities of funds under macro-information facts, and find that some macro-information facts will significantly affect the performance of funds and the model will be more significant. The timing ability of each fund is different, and there must be something making it different. According to the past studies, there were several characters of funds significantly affecting the performance of the funds. That means the characters of funds may affect the strategies of investments, so they may also affect the timing abilities of funds. In this study, I find that the scale of fund and the age of the fund can affect the timing ability of a fund significantly.

Timing in the cerebellum : a matter of network inhibition

Li, Wenke 12 August 2015 (has links)
The motor functions of an animal require precisely timed and coordinated sequences of movements. The cerebellum is crucial for performing these functions with precision. To investigate cerebellar computations involved in precise motor movements, behavioral paradigms such as delay eyelid conditioning have been used. Delay eyelid conditioning trains an animal to close its eye in response to a previously neutral stimulus. The timing of the eyelid closure responses suggests that the cerebellum is capable of keeping track of the elapsed time since the onset of the stimulus. This dissertation proposes a network mechanism for cerebellar timing based on biologically informed simulations of the cerebellum. In chapter 2, a simulation with over a million cells is described. This simulation approaches the observed cerebellar connectivity in several well studied mammals. Graphics processing units (GPUs) provide the computational power necessary to perform this simulation at a practical speed. This chapter describes simulation algorithms that efficiently utilize GPUs. In chapter 3, the simulation is used to explore cerebellar timing mechanisms. The lateral inhibition among cerebellar Golgi cells is observed to be a potential mechanism for robust timing. Lateral Golgi inhibition enables the simulation to better replicate animal eyelid conditioning behavior for longer inter-stimulus intervals. In chapter 4, the emergent network mechanisms of lateral Golgi inhibition are analyzed by decomposing the network into its individual components. This component analysis demonstrates that nonreciprocal connectivity (where one Golgi cell inhibits another but does not receive inhibition in return) is useful for timing. Specifically, removing nonreciprocal connectivity greatly degrades the simulation's ability to keep track of time. This implies that the aforementioned component analyses are relevant to the emergent timing mechanisms of the network. Finally, in chapter 5, this dissertation discusses the relevance and limitations of the computational approach, biological predictions, and component analysis presented in previous chapters. / text

Timing in the Absence of Supraspinal Input: Effects of Temporally Regular Stimulation on Spinal Plasticity

Lee, Kuan Hsien 16 December 2013 (has links)
Prior work has shown that spinal neurons are capable of discriminating between temporally regular and temporally irregular stimulation. These effects have been observed using an in vivo assay of spinal plasticity based on an instrumental learning task, in which response-contingent leg shock produces an increase in flexion duration. Exposure to temporally regular stimulation (fixed spaced stimulation; FT) promotes learning, and temporally irregular stimulation produces a learning deficit. The experiments in this dissertation were designed to test other properties of fixed spaced shock that promote spinal plasticity and the structure responsible for the FT effect. Experiment 1 focused on the minimum number of stimulations necessary to re-establish the capacity to learn (a component of the “FT effect”), finding that180-360 shocks produced a learning deficit and that additional training (540-900 shocks) allowed learning. Experiment 2 found that shock number, not duration of exposure determined whether the FT effect emerged. Experiment 3 investigated if the FT effect emerges after shock was presented in two sessions separated by 24 hrs, and showed that two bouts of 360 shocks yielded the FT effect. Further, the initial bout of fixed spaced shock had a long-term benefit (Experiment 4). The results of Experiment 5 suggested that omitting shocks from a train of FT stimulation has little effect on the benefit of fixed spaced shock treatment. Experiment 6 replicated this observation, showing that randomly deleting half of the shocks (from a 720 FT shock series) had no effect on learning. Further, this schedule also induces a lasting protective effect, blocking the learning deficit produced by variable spaced shock (Experiment 7). To explore whether a central system or a peripheral filter mediates the FT effect, Experiment 8 challenged spinal neurons by phase shifting the relation between fixed spaced stimulation applied to two dermatomes. The FT effect only emerged when stimuli occurred in an alternating pattern across dermatomes, implying regularity is abstracted by a central system. Experiment 9 surgically isolated central pattern generator (L1-L2) from the portion of the spinal cord that mediates instrumental learning (L4-S2), finding that disrupting the connections between these two regions eliminated the FT effect.

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