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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.
21

Area : the big cover-up

McPhail, Diane, University of Western Sydney, College of Arts, School of Education January 2007 (has links)
The research problem reported in this thesis is an investigation of the teaching and learning of area measurement in the early years of school. Research indicates that children confuse the measurement of area and perimeter and also the use of linear and two-dimensional units of measure. The first phase of the study investigated the knowledge and skills which underpin an understanding of the L x B formula for calculating rectangular area. Those factors were used to plan a teaching program of four lessons for Year 1 and Year 2 children, focusing on: establishing the attribute of area; making, describing and drawing the spatial structure of arrays of repeated informal units to measure areas; and methods of counting to determine the total number of units. The effectiveness of the program was evaluated by implementing the lessons in four classes. Lessons planned from the then current syllabus were implemented in another four classes. Comparison of student learning outcomes from all classes indicated that the research lessons were more effective in assisting children to develop an understanding of a grid pattern or array of repeated informal units. The second phase of this study described the researcher’s investigation, design and trial of teacher professional learning strategies which would assist teachers to adopt successful methods of teaching young children to measure area. Seventeen volunteer teachers in seven school teams participated in one of three models of professional learning, based on varying levels of consultancy support. The models were based on the provision of lesson notes and teaching materials, facilitation of team meetings to discuss the implementation, and the provision of additional time to interview individual children following each lesson. Participation in the project assisted all of the participating teachers to develop their content knowledge and to modify their teacher-centred teaching practices. The key strategies and factors which contributed to this success included ongoing school based professional dialogue and support, the provision of a teaching program which emphasised students’ conceptual development within a sequence of activities, the role played by teacher leaders within each team, opportunities to develop questioning techniques and the motivation and disposition of the participating teachers.ABSTRACT / Doctor of Philosophy (PhD)
22

Jämförelse av bonitering enligt övre höjd och ståndortsegenskaper i yngre tallskog

Miekk-oja, Olli January 2010 (has links)
I studien jämfördes bonitering med ståndortsegenskaper och övre höjd i en yngre tallskog i Mellansverige. I jämförelse mellan olika provytor på likvärdig mark och efter olika skötselåtgärder gav de två boniteringsmetoderna samma bonitet, trots variation i antal typarter och olika resultat vad gäller markvegetationstyp. Resultaten kan möjligen vara lokalt representativa men behöver ett större material för att kunna generaliseras på kommunnivå eller större.
23

Developing volume and taper equations for Styrax tonkinensis in Laos

Ounekham, Khamsene January 2009 (has links)
A volume equation for predicting individual tree volume, and a taper function for describing a stem profile were developed for a little known species, Styrax tonkinensis (Siam benzoin) in northern Laos. The species has high potential commercial value and can make an important contribution to the local economy. It can provide two different types of products, a non-wood product (benzoin resin) and timber. In Laos, the most important product is currently resin, and the use of timber for commercial purposes is rare. One reason is that information about the timber is not available. In Vietnam, on the other hand, the species is an import pulpwood species. Data used in this study came from 73 trees. Trees were purposely selected to ensure coverage of a full range of tree sizes. Measurement was undertaken only on over-bark diameters due to some constraints, limitations and problems during the field data collection. However, due to the importance of under-bark volume for this species, a small available dataset was used to build a bark model as an interim guide to the errors associated with using over-bark models for estimating under-bark volumes. From this bark model, errors in estimating under-bark volumes of trees with diameters at breast height between 10cm and 17 cm were approximately 18%. Nineteen individual volume models, and 7 individual taper functions were compared for bias and precision. Collective names for the volume equations tested include single-entry, double-entry, logarithmic, combined variables. Most volume models had similar bias but a few were clearly biased. The models with similar bias were further evaluated by four common statistics including bias, standard error of estimates, standard deviation of residuals and mean absolute deviation. The results showed that a five parameter model was ranked first, and was the most precise model. However, the magnitudes of difference in prediction errors between this model and other models, particularly the three parameter model were not significant. For practical purposes, the simpler model was preferred. Seven taper functions tested here belong to three different groups including single taper equations, compatible taper equations and segmented taper equations. Evaluation of taper equations used the same residual analysis procedures and criteria as those applied with volume equations. Graphical residual analysis showed that most taper models had similar precision with their errors in diameter predictions being similar in range. However, some models showed obvious bias. The most highly ranked taper model was a compatible taper model of polynomial form. It was the least biased model. The second ranked model was a single, simple model. This latter model is relatively simple to apply, but it is not compatible with the volume model, yielding slightly different estimates of volume if it is integrated and rotated around the longitudinal axis of a tree. However, if the sole purpose is to describe tree taper, it is the best model to use.
24

Area the big cover-up /

McPhail, Diane. January 2007 (has links)
Thesis (Ph.D.)--University of Western Sydney, 2007. / "A thesis submitted to the University of Western Sydney, College of Arts, School of Education in fulfilment of the requirements for the degree of Doctor of Philosophy." Includes bibliography.
25

An Assessment of the Utility of a Non-Metric Digital Camera for Measuring Standing Trees

Clark, Neil A. 11 November 1998 (has links)
A method is set forth which makes use of a commercially available, non-metric, solid-state matrix camera to capture spatial and spectral data from an individual tree bole that can be used to measure characteristics about the stem. In this study diameters and heights were measured and used to estimate the volume of 20 red oak (Quercus spp.) stems ranging in diameter at breast height from 16 to over 60 cm and height from 12 to 20 meters. Images were taken from four orthogonal directions around the each stem. Diameter estimates from matching camera to stem distances (3 to 15 meters) of opposite sides were arithmetically averaged. Two arithmetic averages from perpendicular directions were then geometrically averaged. It was found that locating the camera farther from the tree led to more consistent results over the entire stem while locating it closer to the tree provided the most precise estimates provided the inclination angle did not exceed 45 degrees. This method resulted in geometric mean diameter estimates within ± 4 cm for all heights combined when obtained at a distance of 12 m or greater using a 95 % chi-square maximum anticipated error statistic. Error increases with increased stem height from ± 3 cm to ± 7 cm for heights from 1 to 20 meters. In general, the error is equivalent to 3 times the instrument precision, which varies with distance. Two-thirds of the time volume estimates were within 8 percent, which is quite an improvement over the 30 percent interval afforded by an appropriate volume equation. / Master of Science
26

Estimating the marginal productivity of pesticides on irrigated corn and grain sorghum farms in western Kansas

Sleper, James R. January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
27

Root Growth-Rings and Chronology

Schulman, Edmund 07 1900 (has links)
No description available.
28

Estudo do efeito analgÃsico do topiramato em modelos de dor aguda e neuropatia diabÃtica / Study of the analgesic effect of the Topiramate in acute pain and diabetic neuropatic animal models

Luciano da Silva Lopes 24 May 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / No presente estudo, o Topiramato (TP) foi avaliado em modelos de dor aguda e de dor neuropÃtica diabÃtica. Camundongos Swiss machos foram utilizados nos testes de nocicepÃÃo aguda (formalina, placa quente e capsaicina) e ratos Wistar machos no teste de dor neuropÃtica (filamentos de von Frey). No teste da formalina (2 %; 20 ÂL/i.pl.), foi quantificado o tempo que o animal lambia a pata que recebeu o estÃmulo durante 0-10 min (fase 01) e 20-40 min (fase 02). Os resultados mostraram uma reduÃÃo na segunda fase (***p<0,001) nas trÃs doses utilizadas do TP, enquanto que apenas a maior dose mostrou efeito na primeira fase do teste (***p<0,001). O efeito do TP (80 mg/Kg) foi revertido pela naloxona 2 mg/Kg na segunda fase do teste da formalina , mas nÃo pela glibenclamida 3mg/Kg, ciproeptadina 5 mg/Kg e ondansetrona 0,5 mg/Kg quando comparado com o controle em ambas as fases. No teste da placa quente (52Â) foi verificada a reaÃÃo do camundongo ao estÃmulo tÃrmico onde o animal responde tentando pular ou lamber uma de suas patas traseiras. Os animais foram submetidos a placa aos 00, 30, 60, 120 e 240 min apÃs os tratamentos e comparou-se os grupos que receberam TP nas diferentes doses ( 20, 40 e 80 mg/Kg) e o grupo controle. Nesse modelo, TP demonstrou atividade aos 90 e 120min (**p<0,01; ***p<0,001) apenas na maior dose utilizada (80 mg/Kg). Em outro protocolo, os animais receberam capsaicina (20 ÂL, 2 Âg/ i.pl), sendo quantificado o tempo durante 5 min que estes lamberam ou morderam a pata estimulada, com comparaÃÃo posterior entre os grupos NÃo se verificou efeito significativo de TP em todas as doses utilizadas quando comparado com o controle. Para avaliaÃÃo da aÃÃo antinociceptiva em dor neuropÃtica, os animais foram inicialmente induzidos a diabetes com estreptozotocina 40 mg/Kg i.p e apÃs trinta dias foram submetidos ao teste com filamentos de von. NÃo se verificou efeito significativo do TP nas doses utilizadas quando comparado com o controle. O TP nÃo alterou a freqÃÃncia de locomoÃÃo dos animais no teste do campo aberto e no teste do Rota rod e nÃo aumentou o nÃmero de quedas nem diminuiu o tempo de permanÃncia na barra giratÃria, sugerindo que o TP nÃo exerce sua atividade antinociceptiva por aÃÃo depressora ou relaxante muscular. Em conclusÃo, a partir desses resultados podemos sugerir que o TP apresenta efeito antinociceptivo frente a diferentes estÃmulos de dor aguda, mas nÃo na dor neuropÃtica diabÃtica. O efeito analgÃsico nos testes de dor aguda, provavelmente envolve sistema opiÃide, porÃm nÃo os canais de potÃssio sensÃveis ao ATP e sistema serotoninÃrgico / In the present study, Topiramate (TP) was evaluated in acute pain and diabetic neuropathic animal models. Male Swiss mice were used in the tests of acute nocicepcion (formalin, hot plat and capsaicin) e male Wistar rats in the neuropathic pain test (filaments of von Frey). In the formalin test (2%, 20 ÂL/i.pl), it was measured the time spent by the animal licking the left hind paw which received the stimulation during 0-10 min (phase 01) and 20-40 min (phase 02).The results showed a reduction of the second phase (*** p<0.001) in the three doses used of TP while only the biggest dose showed effect in the first stage of test (*** p< 0.001). The TP effect (80 mg/Kg) was reverted by naloxone 2 mg/kg in the second phase of the test of the formalin, but not for glibenclamide 3 mg/kg, cyproeptadine 5 mg/kg and ondansetron 0.5 mg/kg when compared to control in both phases. In the hot plate test (52Â) was analysed the reaction of the mouse to the thermal stimulation where the animal respond tryning to jump or to lick one of its brack legs. The animals had been submitted the plate to 00, 30, 60 and 120 min after the treatments and compared the groups that had received TP in the different doses (20,40 e 80 mg/kg). The results showed, TP demonstrated activity to 90 and 120 min (**p < 0.01; *** p < 0.001) only in the biggest dose used (80mg/kg). In another protocol, the animals received capsaicin (20 ÂL/2Âg/i.pl), but the results ere not significant. For evaluations of the antinociceceptive action in neuropathic pain, the animals had been initially induced diabetes with streptozotocine 40 mg/Kg i.p. and after thirty days had been submitted to the test with filaments of von Frey. No significant effect of TP was observed in all doses used when compared with the controls. TP did not modify the frequency of locomotion of the animals in the open field and presented no effect in the Rota rod test suggesting that the TP does not exert its analgesic effect by depressive actions or relaxant muscular activity. In conclusion, the results may suggest that TP presents antinociceptive effect front the different stimulations of acute pain, but not in diabetic neuropathic pain. The analgesic effect in acute pain, probably involves system opioid, and seems do not involve potassium canals or serotoninergic system
29

Diagnostikos virpesių matavimas / Vibration mensuration

Jakubovskij, Oleg 30 June 2009 (has links)
Vibracijų diagnostika yra pagrindinis metodas, naudojamas įrenginių parametrų stebėjimui, kadangi būtent ši priemonė padeda nustatyti ir įvertinti mechaniniuose įrenginiuose kylančias problemas bei gedimus. Dirbančio pramoninio įrenginio su besisukančiomis dalimis vibracijų lygis yra vienas iš patikimiausių jų mechaninės būklės, surinkimo ir reguliavimo kokybės požymių. Maksimalių leidžiamų eksploatacinių vibracijų lygių nustatymas ir nuolatinė automatinė jų kontrolė leidžia padidinti įrenginių darbo patikimumą, jų aptarnavimo saugumą, sumažinti avarinių prastovų laiką ir sugadintų mechaninių dalių nuostolius. / Vibration refers to mechanical oscillations about an equilibrium point. The oscillations may be periodic such as the motion of a pendulum or random such as the movement of a tire on a gravel road. Vibration is occasionally "desirable". For example the motion of a tuning fork, the reed in a woodwind instrument or harmonica, or the cone of a loudspeaker is desirable vibration, necessary for the correct functioning of the various devices. More often, vibration is undesirable, wasting energy and creating unwanted sound – noise. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically unwanted. Such vibrations can be caused by imbalances in the rotating parts, uneven friction, the meshing of gear teeth, etc. Careful designs usually minimize unwanted vibrations.
30

A mechanism for tracking the effects of requirement changes in enterprise software systems

Datta, Subhajit. Engelen, Robert A. van. January 2006 (has links)
Thesis (M.S.)--Florida State University, 2006. / Advisor: Robert van Engelen, Florida State University, College of Arts and Sciences, Dept. of Computer Science. Title and description from dissertation home page (viewed Sept. 22, 2006). Document formatted into pages; contains ix, 47 pages. Includes bibliographical references.

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