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1

Sandford, Jonathan M. "Detecting changes in network performance from low level measurements." Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/12878.

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The Internet and associated network technologies are an increasingly integral part of modem day working practices. With this increase in use comes an increase in dependence. For some time commentators have noted that given the level of reliance on data networks, there is a paucity of monitoring tools and techniques to support them. As this area is addressed, more data regarding network perfonnance becomes available. However, a need to automatically analyse and interpret this perfonnance data now becomes imperative. This thesis takes one-way latency as an example perfonnance metric. The tenn 'Data Exception' is then employed to describe delay data that is unusual or unexpected due to some fundamental change in the underlying network perfonnance. Data Exceptions can be used to assess the effect of network modifications and failures and can also help in the diagnosis of network faults and perfonnance trends. The thesis outlines how Data Exceptions can be identified by the use of a two-stage approach. The Kolmogorov-Smirnov test can initially be applied to detect general changes in the delay distribution, and where such a change has taken place, a neural network can then be used to categorise the change. This approach is evaluated using both a network simulation and a test network to generate a range of delay Data Exceptions.
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Nitsche, H., J. Fietz, and S. Niese. "LOWRAD 96, Methods and Applications of Low-Level Radioactivity Measurements." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-30206.

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3

Nitsche, H., J. Fietz, and S. Niese. "LOWRAD 96, Methods and Applications of Low-Level Radioactivity Measurements." Forschungszentrum Rossendorf, 1997. https://hzdr.qucosa.de/id/qucosa%3A21847.

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4

Lee, Briony Kate. "Electrochemical measurements of low level metal release from stainless steel into low chloride solutions." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410603.

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5

Montarou, Carole C. "Low-level birefringence methods applied to the characterization of optical fibers and interconnects." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6993.

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Birefringence measurements are of great importance in a plethora of applications spanning from biology to optical communications. Birefringence measurements of nerve-fiber layers have emerged as an important diagnostic technique for early detection of glaucoma. Stress-induced birefringence in optical devices affects their performances by causing Polarization-Mode Dispersion (PMD) and Polarization-Dependent Loss (PDL). Stress-relaxation constitutes a key phenomenon governing the fabrication of some optical devices such as Long-Period Fiber Gratings (LPFGs). This drives the need to develop accurate optical instrumentation techniques to evaluate form and stress-induced birefringence. This thesis deals with the development of new high-accuracy techniques for the characterization of stress-induced birefringence in optical devices. The new Two-Waveplate Compensator (TWC) technique is presented for single-point retardation measurements. It is extensively compared theoretically and experimentally to existing techniques including the Snarmont and Brace-Khler techniques. The Phase-Stepping Two-Waveplate Retarder (PSTWR) is also presented for high-accuracy measurements of retardation magnitude and orientation. The Colorimetry-Based Retardation Method (CBRM) is presented to measure retardation using white-light interference colors. The technique is implemented using a polarization microscope and a spectrophotometer. The TWC and the Brace-Khler methods are implemented for full-field retardation measurements using a polarization microscope. Their accuracies are quantified over the entire field-of-view for small retardations. They are applied to the stress-induced birefringence imaging of LPFGs and polymer pillar waveguides. The TWC technique achieves an accuracy of 0.06 nm and a sensitivity of 0.07 nm. The Brace- Khler technique achieves an accuracy of 0.04 nm and a sensitivity of 0.09 nm. The spatial resolution of both techniques is 0.45 and #61549;m. A Fourier-based algorithm is presented to compute the inverse Abel transform relating the retardation to the axial residual stress profile in optical fibers. It is used to calculate the residual stress profiles of single-mode fibers from full-field retardation measurements with the TWC and Brace- Khler techniques. The stress profiles computed in this work are in very good agreement with previously reported results in the literature. The TWC technique produces the most accurate stress measurements. The TWC technique is used to investigate the stress-relaxation phenomena in LPFGs fabricated using CO2 laser irradiations.
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Nitsche, Heino, and Siegfried Niese. "LOWRAD 96; Methods and Applications of Low-Level Radioactivity Measurements; Proceedings of a Workshop Rossendorf/Dresden, 7-8 November 1996." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31092.

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7

Nitsche, Heino, and Siegfried Niese. "LOWRAD 96; Methods and Applications of Low-Level Radioactivity Measurements; Proceedings of a Workshop Rossendorf/Dresden, 7-8 November 1996." Forschungszentrum Rossendorf, 1997. https://hzdr.qucosa.de/id/qucosa%3A21936.

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8

Mott, J. E. "Search for double beta decay of 82Se with the NEMO-3 detector and development of apparatus for low-level radon measurements for the SuperNEMO experiment." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1418838/.

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The 2νββ half-life of 82Se has been measured as (9.93 ± 0.14 (stat) ± 0.72 (syst)) × 10^19 yr using a 932 g sample measured for a total of 5.25 years in the NEMO-3 detector. The corresponding nuclear matrix element is found to be 0.0484 ± 0.0018. In addition, a search for 0νββ in the same isotope has been conducted and no evidence for a signal has been observed. The resulting half-life limit of > 2.18 × 10^23 yr (90% CL) for the neutrino mass mechanism corresponds to an effective Majorana neutrino mass of < 1.0 - 2.8 eV (90% CL). Furthermore, constraints on lepton number violating parameters for other 0νββ mechanisms, such as right-handed current and Majoron emission modes, have been set. SuperNEMO is the successor to NEMO-3 and will be one of the next generation of 0νββ experiments. It aims to measure 82Se with an half-life sensitivity of 10^26 yr corresponding to < 50 - 100 meV. Radon can be one of the most problematic backgrounds to any 0vBB search due to the high Q value of its daughter isotope, 214Bi. In order to achieve the target sensitivity, the radon concentration inside the tracking volume of SuperNEMO must be less than 150 μBq/m3. This low level of radon is not measurable with standard radon detectors, so a “radon concentration line” has been designed and developed. This apparatus has a sensitivity to radon concentration in the SuperNEMO tracker at the level of 40 μBq/m3, and has performed the first measurements of the radon level inside a sub-section of SuperNEMO, which is under construction. It has also been used to measure the radon content of nitrogen and helium gas cylinders, which are found to be in the ranges 70 - 120 μBq/m3 and 370 - 960 μBq/m3, respectively.
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9

Zdražil, Lukáš. "Návrh a optimalizace speciálního nízkoúrovňového zesilovače pro měření vzdušných iontů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-433468.

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This Master thesis deals with low-current measurement in order of picoamps up to a few tens of femtoamps. Such low currents measuring is necessary for determination of air ions concentration. Disturbances, which are otherwise negligible for ordinary measurements must be considered. For example, leakage currents and noise generated in measuring device circuit. The choice of a precise operation amplifier with low input bias current is as important as the selection of low noise passive components. The aim of the thesis is to design and implement a precise low-level amplifier for the purposes of air ions concentration measurements.
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10

Palai-Dany, Tomáš. "Dielektrická spektroskopie karboxymetylcelulózy v časové oblasti." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-233477.

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The dissertation deals with the time-domain dielectric relaxation spectroscopy of carboxymethylcellulose. The main attention was paid to the experimental part of research, mainly to the design and subsequent development of an experimental setup for the measurement of discharge currents and for their processing and analysis. The subject of the measurement is carboxymethylcellulose (CMC), which is a simple polysaccharide used in wide range of applications, among else also in biomedical engineering. The study of CMC properties has required the development of a new experimental set-up of original design, which includes the equilibration (short-circuiting) of a sample before the measurement, charging and discharging at defined time intervals, switching between these two modes, recording of measurement, adjustments and processing of measured signals up to Fourier transformation into the frequency domain and, finally, calculation of complex permittivity of the sample. The frequency dependence of complex permittivity or its imaginary part, obtained by Fourier transformation of discharge current in time domain, is then referred to as the dielectric spectrum. In view of the fact that current measurements were done at very low levels of measured signal (below 10-12 A) the whole measurement was no easy matter. The framework of the work also necessitated studies and subsequent resolution of problems associated with shielding, grounding, presence of noise and sensitivity to various ambient influences. The research work focused on a reliable and trustworthy measurement of very low discharge currents and, subsequently, mathematical processing of noise present in them, i.e., operations with the original, experimentally established signal in time domain, leading in principle to a digital filtration of measured dielectric data. A further pursued objective is the explanation of dielectric parameters of tested carboxymethylcellulose sample in the widest possible frequency spectrum. The integral part of the research was the selection and application of the method for the transformation of the adjusted signal to the frequency domain. The experimental works, including data processing, were carried out in the Department of Physics, Brno FEEC BUT. Measurements were done with Keithley 617 Electrometer, HP4284A Frequency Analyzer and Janis CCS-400-204 cryogenic system. The results were completed with results obtained at the V Department of Experimental Physics, Centre for Electronic Correlations and Magnetism, University of Augsburg, Germany.
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11

Cích, Augustín. "Nízkoúrovňového měření ELF magnetických polí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442410.

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This Master's thesis deals with design of sensor network for synchronised low-level recording of changes in magnetic part of Earth's field in ELF band in multiple places. The goal is acquisition of changes due to solar storm activity, while taking into account, that in research of geomagnetic effects connected with solar events is spectrum of interest broader and reach up to VLF, where a solution is often made of combination of receivers in ELF and VLF, a decision was made, after consulting with thesis supervisor and researchers, that device will be designed for ELF, but can be easily modified, by changing preamplifier, for using in higher frequency bands, creating a solid founding for further measurements and research in this field.
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12

Štefánek, Martin. "Nízkoúrovňová magnetická měření ULF frekvence 0-30 Hz." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242034.

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The work assesses progress in the design of measuring workplace for measuring low level magnetic fields of low frequencies. The thesis describes the basic method of spreading of electromagnetic waves in free losslees ambience. Further is described effect with low level of ultra-low-frequency magnetic fields in the frequency band from 0.01 to 30 Hz for an individual or group of people and also the draft measuring methods for indicating or measuring changes in magnetic fields. Thesis deals with individual blocks of measuring workstation.
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13

Chiu, Yu-yeung, and 趙汝揚. "Environmental radiation monitoring at the low level radioactive waste storage facility in Siu A Chau and development of a particledispersion model in marine environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38573611.

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14

Niese, Siegfried. "Messung geringer Radioaktivitäten in Untertagelaboratorien mit Hilfe mehrdimensionaler Spektrometrie." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-93726.

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In dem Bericht werden Strahlungsquelle aufgeführt, die den Untergrund bei der Messung geringer Radioaktivitäten verursachen und dargestellt wie zur Unterdrückung der kosmischen Strahlung Laboratorien untertägig eingerichtet werden und wie durch Koinzidenz und Antikoinzidenzverfahren der verbleibende Untergrund weiter reduziert werden kann
The radiation sources are described, which causes the background at the measurement of low radioactivities. To reduce the influence of cosmic rays counting devises are installed in underground laboratories. The remaining background may be further reduced by coincidence and anti-coincidence methods
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15

Niese, Siegfried. "Messung geringer Radioaktivitäten in Untertagelaboratorien mit Hilfe mehrdimensionaler Spektrometrie." Verein für Kernverfahrenstechnik und Analytik e.V, 2008. https://slub.qucosa.de/id/qucosa%3A2473.

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In dem Bericht werden Strahlungsquelle aufgeführt, die den Untergrund bei der Messung geringer Radioaktivitäten verursachen und dargestellt wie zur Unterdrückung der kosmischen Strahlung Laboratorien untertägig eingerichtet werden und wie durch Koinzidenz und Antikoinzidenzverfahren der verbleibende Untergrund weiter reduziert werden kann.
The radiation sources are described, which causes the background at the measurement of low radioactivities. To reduce the influence of cosmic rays counting devises are installed in underground laboratories. The remaining background may be further reduced by coincidence and anti-coincidence methods.
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16

Roubal, Zdeněk. "Nízkoúrovňová měření." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-234612.

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The doctoral thesis presents methods for low-level measurements, which are exemplified by the general measurement of air ion concentration. Within the first section, the author progressively identifies certain critical effects influencing the concentration of air ions, and these effects are to be considered in evaluating the uncertainty of the measured concentrations. Thus, the thesis aims to provide a systematic description of the procedures and requirements related to low-level measurements; the proposed description then involves a discussion of the process reliability requirements, namely the factors of repeatability, elimination of errors, and definition and describability of measurement uncertainties. Such methodology facilitates, among other activities, the long-term monitoring of air ion concentration in extreme environments, including caves or spaces characterized by high temperatures and humidity. The use of common methods for determining the air ion mobility spectrum is accompanied by a number of disturbing effects, such as spurious fluctuation in the concentration of air ions in time. The experimental section of the thesis describes the testing of different configurations of the measuring device (a collecting electrode and a polarization capacitor); at this stage, we seek the most advantageous distribution of the electrostatic field in the sensor – a Gerdien tube. The systematic suppression of the influence of spurious fluctuations in air ion concentration during the measurement of saturation characteristics is carried out with the least-squares numerical method (as a supporting element), a hybrid technique to describe and evaluate the experimental model. In the second part of the thesis, the methodology of low-level measurement is complemented with procedures for the measurement of freezing potential. This latter domain, as an overall experimental approach applicable during phase changes of the sample, has hitherto not been sufficiently characterized from the metrological perspective, in an up-to-date manner; several subregions of the said domain remain somewhat obscured and deserve significantly more attention. In the given context, this thesis systematically considers a problem where comparable measurement results produced by multiple authors are not available. The measuring methodology proposed herein was utilized in applied research to facilitate the fabrication of an apparatus for the experimental measurement of freezing potential in pre-defined samples; the obtained results then lead us to conclusions with respect to the evaluation of effects that cause differences in the measured data, and the results can be further compared with those obtained by other researchers investigating the given segment of the problem.
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17

Baba, Djara Monita Jean. "Performance measurement of district level hospitals in low income countries: participatory development of an instrument to assess inputs, processes, and outputs for evidence-based management and quality improvement." Thesis, Boston University, 2014. https://hdl.handle.net/2144/10935.

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Thesis (Dr.P.H.)--Boston University
BACKGROUND: The potential of hospital performance measurement (HPM) to contribute to improved quality of care and patient outcomes is underrepresented in the health system strengthening literature and no standardized HPM instrument exists for hospitals in developing countries. The problem centered Participatory Action Research (PAR) approach is particularly suited to addressing complex organizational problems in low resource settings and is gaining acceptance as an applied research method in healthcare settings. METHODS: This quasi-experimental study using the PAR approach was carried out in 4 hospitals in Cameroon. Quantitative (415 surveys) and qualitative (129 interviews and 77 observations) methods examined how participating in the design of a HPM instrument influences health personnel's knowledge, attitude, interest, and intention to continue use of performance measurement for quality improvement. Changes in scores for the above outcomes from before and after implementation of the performance indicators were compared to scores from a non-participating control hospital at the same time points. RESULTS: Personnel designed and pilot tested performance measurement indicators in all hospital services. Hospitals that actively participated in instrument design showed a statistically significant increase in HPM knowledge and attitude, and were more likely to report intention to continue using HPM as compared to the non-participating hospital. Hospital personnel participating in the design process were more aware of the workload barriers to implementing HPM but nonetheless were more motivated to continue the HPM effort. In addition, the PAR approach fostered ownership, increased skills, raised awareness of performance gaps, and led to a contextually appropriate tool. CONCLUSIONS: The results of this study demonstrate the feasibility of designing and implementing an HPM instrument in a low-resource health care system and highlight the positive benefits of the PAR approach. Further research is needed to determine the effect of regular HPM on quality of care and its sustainability over time in resource constrained settings.
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Winkler, Anderson M. "Widening the applicability of permutation inference." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:ce166876-0aa3-449e-8496-f28bf189960c.

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This thesis is divided into three main parts. In the first, we discuss that, although permutation tests can provide exact control of false positives under the reasonable assumption of exchangeability, there are common examples in which global exchangeability does not hold, such as in experiments with repeated measurements or tests in which subjects are related to each other. To allow permutation inference in such cases, we propose an extension of the well known concept of exchangeability blocks, allowing these to be nested in a hierarchical, multi-level definition. This definition allows permutations that retain the original joint distribution unaltered, thus preserving exchangeability. The null hypothesis is tested using only a subset of all otherwise possible permutations. We do not need to explicitly model the degree of dependence between observations; rather the use of such permutation scheme leaves any dependence intact. The strategy is compatible with heteroscedasticity and can be used with permutations, sign flippings, or both combined. In the second part, we exploit properties of test statistics to obtain accelerations irrespective of generic software or hardware improvements. We compare six different approaches using synthetic and real data, assessing the methods in terms of their error rates, power, agreement with a reference result, and the risk of taking a different decision regarding the rejection of the null hypotheses (known as the resampling risk). In the third part, we investigate and compare the different methods for assessment of cortical volume and area from magnetic resonance images using surface-based methods. Using data from young adults born with very low birth weight and coetaneous controls, we show that instead of volume, the permutation-based non-parametric combination (NPC) of thickness and area is a more sensitive option for studying joint effects on these two quantities, giving equal weight to variation in both, and allowing a better characterisation of biological processes that can affect brain morphology.
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19

Hanzelka, Michael. "Nízkoúrovňová měření a vyhodnocení vlivu magnetických polí na lidský organismus, jeho chování a rozhodování." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-295646.

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Presents results of research in the field of low-level electromagnetic fields interacting with the higher organisms, in the frequency band from 0,01 to 30 Hz effect on the individual or social group. Provides a description of the methodology of measuring and evaluating the impact of workplace assembled measuring low-level electromagnetic fields, extremely low frequency (ELF) on a sample of respondents. It was proposed measuring device for monitoring and evaluating how respondents' reactions to changes in the geomagnetic or external - external magnetic / electromagnetic field and to work for the measurement and evaluation of changes in external magnetic fields very low levels (ELF). This work is designed to process and evaluate implemented within experimental research into the influence of low-level magnetic fields in the Earth's resonator psychophysiological parameters of human organism and its behavior and decision-making. The work confirmed the influence of low-level magnetic fields on the psychophysiological parameters of the organism to be simultaneously confirmed the hypothesis established in accordance with the objectives of work.
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Predrag, Filipov. "Fizikalna terapija primenom lasera male snage u subakutnom lumbalnom bolnom sindromu." Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110579&source=NDLTD&language=en.

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Uvod: Lumbalni bolni sindrom (LBS) podrazumeva tegobe u vidu bolova, u lumbalnom ili lumbosakralnom segmentu kičmenog stuba, sa ili bez iradijacije u donje ekstremitete, uz poremećaj funkcije umbosakralnog dela kičmenog stuba, zaštitnu mišićnu reakciju na bol (spazam) uz moguće znake senzitivnog poremećaja. Laser male snage (LMS) ima široku primenu u fizikalnoj medicini i rehabilitaciji zbog analgetskog, antiinflamatornog, antiedematoznog i biostimulativnog dejstva. Cilj rada: Glavni ciljevi su bili da se utvrdi da li fizikalna terapija primenom LMS utiče na smanjenje bola, povećanje pokretljivost lumbalne kičme, smanjenje spazma pravertebralne muskulature, kao i na smanjenje funkcionalne osnesposobljenosti u subakutnom LBS. Materijal i metode: Sprovedena je prospektivna studija na 123 pacijenata (50 muškaraca i 73 žene), različitih profesija, izabranih metodom slučajnog izbora, prosečne životne dobi 32.59±5.67 godina (ispitivana grupa 31.87±5.84, kontrolna grupa 33.31±5.45, raspon od 19-45). U studiju su uključeni ispitanici koji su prvi put doživeli lumbalni bolni sindrom koji su pregledani u Odeljenju za fizikalnu medicinu i rehabilitaciju Doma zdravlja Novi Sad. Ispitivanu grupu je činio 61 ispitanik koji su uključeni u fizikalni tretman, primenom laseroterapije i kineziterapije uz medikamentoznu terapiju. Kontrolnu grupu je činilo 62 ispitanika koji koji su uključeni u fizikalni tretman primenom kineziterapije uz medikamentoznu terapiju. Svim ispitanicima je uzeta anamneza, obavljen klinički pregled, izvršena samoprocena bola i popunjavali su upitnike. Navedeno ispitivanje je sprovedeno na početku tretmana, nakon 6 nedelje i nakon sprovedenog tretmana. Korišćeni su sledeći upitnici: vizuelna analogna skala (VAS), standardizovani upitnici za merenje funkcionalnog ishoda - The Oswestry Disability Index (ODI), The Rolland&Morris Disability Questionnaire (RMDQ) i SF-36 upitnik. Rezultati: Rezultati ukazuju da se intenzitet bola meren VAS skalom u obe ispitivane grupe značajno smanjivao tokom svih posmatranih perioda ispitivanja, pri čemu dobijena razlika između dve grupe nije statistički značajna (p=0.904). Pokretljivost lumbalne kičme u obe ispitivane grupe tokom posmatranog perioda se značajno povećala tokom svih posmatranih perioda ispitivanja, pri čemu dobijena razlika između dve grupe nije statistički značajna (p=0.798). U obe ispitivane grupe spazam paravertebralne muskulature se značajno smanjivao tokom svih posmatranih perioda ispitivanja, dok dobijena razlika između grupa nije statistički značajna (p=0.453). Funkcionalna onesposobljenost pacijenata (procenjivana smanjenjem funkcionalne onesposobljenosti ODI i RMDQ) se značajno smanjivala u obe ispitivane grupe pacijenata tokom svih posmatranih perioda ispitivanja. Dobijena razlika u skorovima procenjivana RMDQ između ispitivanih grupa pacijenata nije statistički značajna (p=0.648), kao i putem ODI skora između ispitivanih grupa (p=0.311). Procena funkcionalne onesposobljenosti putem procene kvaliteta života (SF-36), ukazuje da se kvalitet života značajno povećavao u svim ispitivanim skorovima u obe ispitivane grupe tokom svih posmatranih perioda ispitivanja. Nema razlika u funkcionalnoj onesposobljenost (SF-36), odnosno nema razlike u kvalitetu života u skorovima fizičko funkcionisanje, ograničenje zbog emocionalnih problema, socijalno funkcionisanje, mentalno zdravlje, telesni bol, energija i vitalnost, sumarni skor fizičkog i sumarni skor mentalnog zdravlja između ispitivanih grupa. Dimenzije kvaliteta života u skorovima ograničenje zbog fizičkog zdravlja je značajno bolje u kontrolnoj grupi ispitanika (p=0.028). Dimenzija kvaliteta života u skoru opšte zdravlje je značajno bolje u ispitivanoj grupi pacijenata (p=0.041). Zaključci. Primenom LMS u subakutnom LBS došlo je statistički značajnog smanjenja intenziteta bola, povećanja pokretljivosti lumbalne kičme, smanjenja spazma paravertebralne muskulature, kao i smanjenja funkcionalne onesposobljenosti. S obzirom da ne postoji koncenzus oko primene LMS, kao ni drugih metoda fizikalne terapije u subakutnom stadijumu LBS, navedeni rezultati bi mogli doprineti usvajanju kliničkih smernica, odnosno dijagnostičkih i terapijskih protokola za subakutni LBS.
Introduction: Low back pain syndrome (LBP) implies pain in the lumbar or lumbosacral segment of the spine, with or without irradiation into the lower extremities, with a disorder to the function of the lumbosacral part of the spine, a protective muscular reaction to pain (spasm) and possible signs of a sensory processing disorder. Low-Level Laser Therapy (LLLT) has broad application in physical medicine and rehabilitation due to analgesic, antiinflammatory, anti-edematous and biostimulative effects. Objective: The main objective of this study was to determine whether physical therapy with a LLLT has an effect on reducing pain, increasing mobility in the lumbar spine, reducing spasms of the paravertebral muscle, as well as in reducing functional incapacity in subacute LBP. Material and methods: A prospective study was conducted on 123 patients (50 men and 73 women), of different professions, chosen through random selection, with a mean age of 32.59 ± 5.67 years (examined group 31.87 ± 5.84, control group 33.31 ± 5.45, range 19-45). The study included respondents who had experienced lumbar pain syndrome for the first time and who had been examined in the Department of Physical Medicine and Rehabilitation of the Novi Sad Health Center. The examined group consisted of 61 respondents undergoing physical treatment with the application of LLLT and kinesiotherapy with medication therapy. The control group consisted of 62 respondents undergoing physical treatment with the application of kinesiotherapy with medication therapy. All patients were subject to an anamnesis, a clinical examination, a selfassessment of pain and were required to complete questionnaires. The above study was carried out at the beginning of treatment, after 6 weeks, and after treatment was completed. The following questionnaires were used: Visual Analogue Scale (VAS), standardized questionnaires for assessing functional outcomes – The Oswestry Disability Index (ODI), The Rolland & Morris Disability Questionnaire (RMDQ) and the SF-36 questionnaire. Results: Results indicate that pain intensity assessed using the VAS scale was significantly decreased, in both examined groups, during all observed study periods, where the difference between the two groups was not statistically significant (p = 0.904). Mobility of the lumbar spine was significantly increased, in both examined groups, during all observed study periods, where the obtained difference between the two groups was not statistically significant (p = 0.798). In both examined groups, spasm of the paravertebral musculature significantly decreased during all observed study periods, while the difference between the groups was not statistically significant (p = 0.453). Functional disability of patients (assessed by a reduction of functional disabilities of ODI and RMDQ) significantly decreased in both examined groups of patients during all observed examination periods. The obtained difference in scores assessed via the RMDQ, between the studied patient groups, was not statistically significant (p = 0.648), as well as via the ODI score between the researched groups (p = 0.311). Assessment of functional disability through the assessment of quality of life (SF-36) indicates that the quality of life increased significantly, for all examined scores in both examined groups, during all observed testing periods. There is no difference in functional disability (SF-36), that is, there is no difference in quality of life in score physical functioning, restrictions due to emotional problems, social functioning, emotional wellbeing, bodily pain, energy/vitality, physical and mental health, between the examined groups. The dimensions of quality of life in score role limitations due to physical health problems are significantly better in the control group (p = 0.028). The quality of life dimension in the general health perceptions is significantly better in the examination group (p = 0.041). Conclusions: The application of LLLT in subacute LBP resulted in a statistically significant reduction in pain intensity, increased lumbar spine mobility, decreased spasms of paravertebral musculature, and decreased functional disability. Given that there is no consensus on the use of LLLT, nor any other methods of physical therapy, during the subacute LBP, these results could contribute to the adoption of clinical guidelines, that is, diagnostic and therapeutic protocols for subacute LBP.
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21

Rodrigues, Carolina Almeida. "Efeitos do laser de baixa intensidade em mulheres com disfunção temporomandibular: estudo clínico duplo-cego e randomizado." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/58/58133/tde-17052018-162710/.

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Funções vitais importantes são desempenhadas pelo sistema estomatognático e alterações no equilíbrio que ultrapassem a tolerância fisiológica do sujeito podem gerar um colapso, levando a um distúrbio funcional, conhecido como Desordem Temporomandibular (DTM). A principal característica e o principal motivo pela busca ao tratamento e o sintoma doloroso que afeta negativamente a qualidade de vida do sujeito. O Laser de Baixa Intensidade (LBI) consiste em uma modalidade terapêutica conservadora na redução da dor, porem protocolos eficazes e seus efeitos ainda são controversos na literatura. O objetivo deste estudo foi analisar o efeito do LBI na redução da intensidade e sensibilidade a dor entre as sessões de LBI e durante teste funcional especifico, e avaliar o comportamento eletromiográfico antes e após tratamento. Para tal, 30 mulheres sem sinais e sintomas de DTM foram selecionadas para compor o grupo controle e 59 mulheres diagnosticadas com DTM dolorosa, por meio do Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), passaram por processo de randomização baseado na severidade da DTM que foi obtida através do Índice Temporomandibular, foram designadas aos grupos laser ativo (n=30) e placebo (n=29). Todas as voluntarias passaram inicialmente por um protocolo de avaliação de eletromiografia (EMG), eletrovibratografia (EVG), avaliação de limiar de dor a pressão (LDP) e intensidade de dor (EVA) durante teste funcional especifico, alem da mensuração de abertura bucal. Para os grupos de tratamento, essas analises foram repetidas após o termino do tratamento e com 30 dias de proservação. O tratamento foi realizado com equipamento contendo uma ponta de laser ativo e uma placebo (GaAlAs 780nm) sob protocolos diferentes para ATM (60mW/50segundos 75J/cm2) e para Masseter e Temporal (60mW/20segundos 30J/cm2). Em 8 sessões (2 por semana). Os resultados foram submetidos a analise de variância, posteriormente foi empregado o teste de comparação múltipla de Tukey (nível de significância adotado 5%). Para as analises foi utilizado o procedimento General Linear Models (GLM) do programa computacional lSAS (SAS 9.1, SAS Institute, Cary. NC, USA). Os resultados obtidos mostraram que o LBI ativo e placebo foram capazes de gerar alterações apenas nas variáveis relacionadas diretamente a dor, como a intensidade de dor avaliada entre as sessões, na qual, ambos os grupos apresentaram melhora significante a partir da segunda sessão de tratamento. Alem disso, houve melhora da sensibilidade a dor e da intensidade durante o exercício funcional da mastigação após o tratamento para os dois grupos, porem o grupo laser apresentou maior efetividade na redução destas variáveis. Pode-se concluir que o tratamento com LBI e eficaz para melhora da dor e a diferença entre o tratamento laser ativo e placebo ocorreu apenas nas variáveis de dor mensuradas durante um exercício funcional.
Important vital functions are performed by the stomatognathic system and changes in balance that exceed the physiological tolerance of the subject can lead to a collapse, leading to a functional disorder known as Temporomandibular Disorder (TMD). The main characteristic and the main reason for the search for treatment is the painful symptom that negatively affects the quality of life of the subject. The Low-lever Laser Therapy (LLLT) consists of a conservative therapeutic modality in the reduction of pain, but effective protocols and their effects are still controversial in the literature. The aim of this study was to analyze the effect of LLLT in reducing the intensity and pain sensitivity between sessions of LLLT and during specific functional test, and evaluate the electromyographic behavior before and after treatment. To this end, 30 women with no signs and symptoms of TMD were selected to the control group and 59 women diagnosed with painful TMD, through the Research Diagnostic Criteria for Temporomandibular Disorders (RDC / TMD) underwent randomization process based on severity DTM was obtained by temporomandibular index were assigned to the active laser groups (n = 30) and placebo (n = 29). All volunteers initially underwent electromyography (EMG), electrovibratography (EVG), pressure pain threshold (LDP) and pain intensity (VAS) evaluation during specific functional tests, in addition to the measurement of mouth opening. For treatment groups, these analyzes were repeated after the end of treatment and 30 days of follow up. The treatment was performed with equipment containing an active laser tip and a placebo (GaAlAs - 780nm) under different protocols for ATM (60mW / 50 seconds - 75J / cm2) and for Masseter and Temporal (60mW / 20 seconds - 30J / cm2). In 8 sessions (2 per week). The results were submitted to analysis of variance was later used the multiple comparison test of Tukey (significance level - 5%). For the analysis, the General Linear Models (GLM) procedure of the SAS software (SAS 9.1, SAS Institute, Cary, NC, USA) was used. The results showed that the active LLLT and placebo were able to generate only changes in the variables directly related to pain, such as pain intensity measured between sessions, in which both groups showed significant improvement from the second treatment session. In addition, there was improvement in pain sensitivity and intensity during the functional mastication exercise after treatment for both groups, but the laser group showed greater effectiveness in reducing these variables. It can be concluded that treatment with LLLT is effective for improving pain and the difference between active laser treatment and placebo occurred only in pain variables measured for a functional exercise.
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22

Domagk, Max. "Identifikation und Quantifizierung korrelativer Zusammenhänge zwischen elektrischer sowie klimatischer Umgebung und Elektroenergiequalität." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-211866.

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Eine angemessene Qualität der Elektroenergie ist Grundvoraussetzung für den störungsfreien Betrieb aller angeschlossenen Geräte und Anlagen und spielt in den Verteilungsnetzen moderner Industriegesellschaften wie Deutschland eine zentrale Rolle. Die Elektroenergiequalität (EEQ) wird in Strom- und Spannungsqualität unterteilt. Während die Stromqualität maßgeblich im Verantwortungsbereich der Hersteller von Geräten und Anlagen liegt, sind für die Sicherung einer angemessenen Spannungsqualität im Wesentlichen die Netzbetreiber verantwortlich. Durch die technische Weiterentwicklung bspw. neuer Gerätetechnologien und die zunehmende Integration dezentraler Erzeugungsanlagen wie Photovoltaikanlagen ist zu erwarten, dass die EEQ auch künftig weiter an Bedeutung gewinnt. Die EEQ im Niederspannungsverteilungsnetz ist abhängig von Ort und Zeit und wird durch verschiedene Qualitätskenngrößen beschrieben. Die örtliche und zeitliche Abhängigkeit resultieren aus einer Vielzahl verschiedener Einflussfaktoren, welche sich entweder der elektrischen oder der nicht-elektrischen Umgebung des betrachteten Verteilungsnetzes zuordnen lassen. Die elektrische Umgebung wird durch die Art und Anzahl angeschlossener Verbraucher bzw. Erzeuger (Abnehmer- bzw. Erzeugerstruktur) sowie Struktur und technische Parameter des Verteilungsnetzes (Netzstruktur) bestimmt. Die nicht-elektrische Umgebung umfasst u.a. Einflüsse der klimatischen Umgebung wie bspw. Temperatur oder Globalstrahlung. Ziel dieser Arbeit ist die systematische Identifikation korrelativer Zusammenhänge zwischen den genannten Umgebungseinflüssen und der EEQ sowie deren Quantifizierung auf Basis geeigneter Indizes und Kenngrößen. Die Ergebnisse der Arbeit helfen grundlegende Prinzipien der Ausprägung der Elektroenergiequalität im öffentlichen Verteilungsnetz besser zu verstehen sowie die Verteilungsnetze im Hinblick auf die Elektroenergiequalität zu charakterisieren und zu klassifizieren. Analog zu den Standard-Lastprofilen erfolgt die Definition von Standard-Qualitätsprofilen
Power quality levels in public low voltage grids are influenced by many factors which can either be assigned to the electrical environment (connected consumers, connected genera-tion, network characteristics) or to the non-electrical environment (e.g. climatic conditions) at the measurement site. Type and amount of connected consumers (consumer topology) are expected to have a very high impact on power quality (PQ) levels. The generation topology is characterized by number and kind of equipment and generating installations like photovoltaic systems which are connected to the LV grid. The electrical parameters of the grid define the network topology. The parameters which are most suitable to describe each of the three topologies and the climatic environment will be identified. Voltage and current quality in public low voltage (LV) grids vary depending on location and time. They are quantified by a set of different parameters which either belong to events (e.g. dips) or to variations (e.g. harmonics). This thesis exclusively addresses continuous parameters describing variations. Continuous phenomena like harmonics are closely linked to an one-day-cycle which implies a more or less periodic behavior of the continuous power quality parameters. Consumer topologies such as office buildings or residential areas differ in their use of equipment. Time series analysis is used to distinguish between different consumer topologies and to identify characteristic weeks. The clustering of one-day time series is applied to identify characteristic days within the weeks of certain topologies. Based on the results, emission profiles for certain current quality parameters of different consumer topologies will be defined. Due to the characteristic harmonic current emission of certain consumer topologies which represents the typical user behaviour a classification system is developed. It is used to automatically classify the emission profiles of harmonic currents for unknown measurements and to estimate a likely consumer topology. A classification measure is introduced in order to identify unusual or false classified emission profiles. The usage behaviour of equipment by customers usually varies over the year. Subsequently, the levels of PQ parameters like harmonics may show seasonal variations which are identified by using newly defined parameters. The introduction of new device technologies on a large scale like the transition from incandescent to LED lamps might result in long-term changes to the levels of PQ parameters (e.g. harmonics). The analysis of the long-term behavior (trend) will be applied in order to quantify global trends (looking on the measurement duration as a whole) and local trends (looking on individual segments of the whole time series)
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23

Peixotto, David. "Low-Level Haskell Code: Measurements and Optimization Techniques." Thesis, 2012. http://hdl.handle.net/1911/64648.

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Haskell is a lazy functional language with a strong static type system and excellent support for parallel programming. The language features of Haskell make it easier to write correct and maintainable programs, but execution speed often suffers from the high levels of abstraction. While much past research focuses on high-level optimizations that take advantage of the functional properties of Haskell, relatively little attention has been paid to the optimization opportunities in the low-level imperative code generated during translation to machine code. One problem with current low-level optimizations is that their effectiveness is limited by the obscured control flow caused by Haskell's high-level abstractions. My thesis is that trace-based optimization techniques can be used to improve the effectiveness of low-level optimizations for Haskell programs. I claim three unique contributions in this work. The first contribution is to expose some properties of low-level Haskell codes by looking at the mix of operations performed by the selected benchmark codes and comparing them to the low-level codes coming from traditional programming languages. The low-level measurements reveal that the control flow is obscured by indirect jumps caused by the implementation of lazy evaluation, higher-order functions, and the separately managed stacks used by Haskell programs. My second contribution is a study on the effectiveness of a dynamic binary trace-based optimizer running on Haskell programs. My results show that while viable program traces frequently occur in Haskell programs the overhead associated with maintaing the traces in a dynamic optimization system outweigh the benefits we get from running the traces. To reduce the runtime overheads, I explore a way to find traces in a separate profiling step. My final contribution is to build and evaluate a static trace-based optimizer for Haskell programs. The static optimizer uses profiling data to find traces in a Haskell program and then restructures the code around the traces to increase the scope available to the low-level optimizer. My results show that we can successfully build traces in Haskell programs, and the optimized code yields a speedup over existing low-level optimizers of up to 86% with an average speedup of 5% across 32 benchmarks.
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24

Tseng, Cheng-Fong, and 曾建峰. "Temperature Dependence Hall Measurement and Deep Level Transient Spectroscopy Measurement of Low Temperature MOCVD GaAs." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/87777256483874982059.

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碩士
國立交通大學
電子物理學系
83
We use Temperature Dependence Hall (TDH)measurement and Deep Level Transient Spectroscopy(DLTS) measurement to investigate t- he properties of the low temperature(~500℃) MOCVD GaAs films(LT -GaAs). Using TDH measurement,we can find the concentration and act- ivation energy of the deep level trap。A sample grown at 500℃, using TEGa and TBAs as source precursors ,It is find that the h- igh concentration 3.25×1015 cm-3,trap center located at 0.485 eV below conduction band has a dramatic influence on the electr- ical properties of LT-GaAs samples. In DLTS measurement ,two deep level traps ,peaked at ~0.55 eV and ~0.8 eV below conduction band ,are observed in LT- GaAs s- amples. They are identified as oxygen trap and EL2 trap respect- ively. It is found that the concentration of oxygen trap became larger as the V/III ratio is decreased, no matter of TBAs or As- H3 being used. On the other hand ,the occurrence of EL2 is very sensitive to the growth temperature .The concentration become l- arger at low temperature .We believed that such phenomenon is m- ainly caused by the shortage of reactive Ga atom on the growing surface, resulted from a low temperature growth environment.
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25

Chen, Shin-Hao, and 陳仕豪. "The Measurement of Rat’s Brainwave in vivo by Low Level Laser Stimulation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/63539067113782418337.

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碩士
國立交通大學
光電系統研究所
101
The low level light stimulation has been developed for several decades, but the research on low level light stimulation was always in vitro in the past. There is no record about in vivo low level light stimulation. In this paper, the author designed the home-made laser instrument to study the effect of low level light stimulation in vivo. In order to understand the effect of low level light stimulation in vivo, EEG was used to measure the output. Unlike the conventional EEG analysis used by medical professional, we transferred EEG data by Fast Fourier Transform (FFT) to the frequency-domain signal. Judging the frequency-domain signal intensity, we may able to determine which of the brain wave is responded more rapidly to the LLLS. On the instrumental design, we used 10X optical lens to couple the low level light into the optical fiber. With the flexible fiber, we were able to do the laser stimulation on anesthetized rats in vivo. Of the EEG instru- mentation, we composed the pre-amplifier, Low Pass Filter, Notch Filter and instrumentation amplifier in order to filter out ambient noise and to enhance the brainwave. Finally, we applied a LABVIEW software to do Fast Fourier Transform and analysis of frequency-domain signal. We divided twenty rats into four groups, each group with five rats; two groups were injected with 6-OHDA and the other two groups as blank. Then we separated rats into two different groups to do the light stimulation experiment. We used 1mW power and 840 nm infrared laser stimulation for one minute. The results showed distinct β wave increase trend after light stimulation. The increase trend did wear off after 30 min to one hour. It might be due to the insufficient stimulation’s power or time to make permanent change. In this study, we found that low level light stimulation with our instrument can affect the rat’s brainwave. In the future, we hope to develop the optima stimulation parameters by the corresponding β wave’s intensity. With proper light stimulation parameters and measurable chemical markers, we shall able to learn the change of chemical com- position on rat’s brain specifically. Therefore, we may have a break- through development on the in vivo low level light stimulation therapy.
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Chang, I.-Hung, and 張義鴻. "Brainwave measurement on rats subject to in vivo low‐level light stimulation of substantia nigra at 840 nm wavelength." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/87148742218990767105.

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碩士
國立交通大學
照明與能源光電研究所
102
Low-level light stimulation has been studied for several decades. However, most of the previous studies focused on external light stimulation on living bodies or in vitro light stimulation. Studies on in vivo low-level light stimulation are relatively rare. Therefore, we designed a laser stimulation instrument to investigate the effects of in vivo low-level light stimulation. We used a 10× object lens to couple the laser light with an optical fiber. By using a flexible fiber and special separate design, we were able to accurately implement in vivo light stimulation on rats. In addition, in order to filter out the random signals in electroencephalogram, we used a combination of pre-amplifier, lowpass filter, notch filter, and instrumentation amplifier to filter brainwaves. We then used LabVIEW software to conduct fast Fourier transform and frequency-domain signal analysis. The experiment was divided into three groups, namely, the time, energy, and power groups. Different combinations of experimental parameters were used for light stimulation to observe the common EEG phenomenon of these groups. For the time group, an infrared laser with 1 mW power and 840 nm wavelength was used for stimulation at 1, 3, 5, and 10 min. We found that stimulation for 5 min resulted in the most brainwave differences between the before and after light stimulation states. On the basis of this implication, a stimulating energy of 300 mJ was used as the baseline for the energy group. For the energy group, an 840 nm laser with the same stimulating energy but with different time and power combinations was used. We found that stimulation for 5 min had the most apparent brainwave response. Consequently, we proceeded to use a stimulus duration of 5 min for the power group with varied stimulation powers at 0.5, 1, 1.66, 5, and 10 mW. The results showed that 1 mW power induced the most brainwave differences between the before and after light stimulation states in this experiment. Therefore, we found that low-level light stimulation with our instrument could affect rat brainwaves. We then performed cross-experiment analysis in the three groups to obtain fine response parameters. In the future, we could coordinate chemical analysis or other analysis methods to investigate the changes in the chemical composition of rat brains. Finally, through this study, we hope to promote the advancement of low-level light stimulation therapy.
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27

Domagk, Max. "Identifikation und Quantifizierung korrelativer Zusammenhänge zwischen elektrischer sowie klimatischer Umgebung und Elektroenergiequalität." Doctoral thesis, 2015. https://tud.qucosa.de/id/qucosa%3A29896.

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Abstract:
Eine angemessene Qualität der Elektroenergie ist Grundvoraussetzung für den störungsfreien Betrieb aller angeschlossenen Geräte und Anlagen und spielt in den Verteilungsnetzen moderner Industriegesellschaften wie Deutschland eine zentrale Rolle. Die Elektroenergiequalität (EEQ) wird in Strom- und Spannungsqualität unterteilt. Während die Stromqualität maßgeblich im Verantwortungsbereich der Hersteller von Geräten und Anlagen liegt, sind für die Sicherung einer angemessenen Spannungsqualität im Wesentlichen die Netzbetreiber verantwortlich. Durch die technische Weiterentwicklung bspw. neuer Gerätetechnologien und die zunehmende Integration dezentraler Erzeugungsanlagen wie Photovoltaikanlagen ist zu erwarten, dass die EEQ auch künftig weiter an Bedeutung gewinnt. Die EEQ im Niederspannungsverteilungsnetz ist abhängig von Ort und Zeit und wird durch verschiedene Qualitätskenngrößen beschrieben. Die örtliche und zeitliche Abhängigkeit resultieren aus einer Vielzahl verschiedener Einflussfaktoren, welche sich entweder der elektrischen oder der nicht-elektrischen Umgebung des betrachteten Verteilungsnetzes zuordnen lassen. Die elektrische Umgebung wird durch die Art und Anzahl angeschlossener Verbraucher bzw. Erzeuger (Abnehmer- bzw. Erzeugerstruktur) sowie Struktur und technische Parameter des Verteilungsnetzes (Netzstruktur) bestimmt. Die nicht-elektrische Umgebung umfasst u.a. Einflüsse der klimatischen Umgebung wie bspw. Temperatur oder Globalstrahlung. Ziel dieser Arbeit ist die systematische Identifikation korrelativer Zusammenhänge zwischen den genannten Umgebungseinflüssen und der EEQ sowie deren Quantifizierung auf Basis geeigneter Indizes und Kenngrößen. Die Ergebnisse der Arbeit helfen grundlegende Prinzipien der Ausprägung der Elektroenergiequalität im öffentlichen Verteilungsnetz besser zu verstehen sowie die Verteilungsnetze im Hinblick auf die Elektroenergiequalität zu charakterisieren und zu klassifizieren. Analog zu den Standard-Lastprofilen erfolgt die Definition von Standard-Qualitätsprofilen.
Power quality levels in public low voltage grids are influenced by many factors which can either be assigned to the electrical environment (connected consumers, connected genera-tion, network characteristics) or to the non-electrical environment (e.g. climatic conditions) at the measurement site. Type and amount of connected consumers (consumer topology) are expected to have a very high impact on power quality (PQ) levels. The generation topology is characterized by number and kind of equipment and generating installations like photovoltaic systems which are connected to the LV grid. The electrical parameters of the grid define the network topology. The parameters which are most suitable to describe each of the three topologies and the climatic environment will be identified. Voltage and current quality in public low voltage (LV) grids vary depending on location and time. They are quantified by a set of different parameters which either belong to events (e.g. dips) or to variations (e.g. harmonics). This thesis exclusively addresses continuous parameters describing variations. Continuous phenomena like harmonics are closely linked to an one-day-cycle which implies a more or less periodic behavior of the continuous power quality parameters. Consumer topologies such as office buildings or residential areas differ in their use of equipment. Time series analysis is used to distinguish between different consumer topologies and to identify characteristic weeks. The clustering of one-day time series is applied to identify characteristic days within the weeks of certain topologies. Based on the results, emission profiles for certain current quality parameters of different consumer topologies will be defined. Due to the characteristic harmonic current emission of certain consumer topologies which represents the typical user behaviour a classification system is developed. It is used to automatically classify the emission profiles of harmonic currents for unknown measurements and to estimate a likely consumer topology. A classification measure is introduced in order to identify unusual or false classified emission profiles. The usage behaviour of equipment by customers usually varies over the year. Subsequently, the levels of PQ parameters like harmonics may show seasonal variations which are identified by using newly defined parameters. The introduction of new device technologies on a large scale like the transition from incandescent to LED lamps might result in long-term changes to the levels of PQ parameters (e.g. harmonics). The analysis of the long-term behavior (trend) will be applied in order to quantify global trends (looking on the measurement duration as a whole) and local trends (looking on individual segments of the whole time series).
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