Search results for "anova"
showing 10 items of 95 documents
A depth dependent analytical approach to determine material breaking in SPIF
2007
Formability is a relevant issue in Single Point Incremental Forming (SPIF) process since it is one of the main point of strength together to the possibility to avoid any dedicated die. Several researches agree that, depending on working material and process parameters, in SPIF operations there is a threshold slope of the wall that cannot be overcame without material breaking. If deep Incremental Forming is taken into account, despite the previous statement it is possible to demonstrate that, when the threshold angle is imposed, there is a relation between the actual workpiece depth and the material breaking approaching. In this paper, the latter relationship was investigated and formally de…
Sakārtotu ZnO nanovadu masīva veidošana izmantojot anodizēta alumīnija oksīda matricas
2019
Sakārtotu ZnO nanovadu masīva veidošana, izmantojot anodizēta alumīnija oksīda matricas. Dutovs A., zinātniskais vadītājs Dr. Chem., asoc. prof. Erts D. un pētnieks M.Sc. Biol. Maļinovskis U. Bakalaura darbs, 38 lappuses, 16 attēli, 2 tabulas, 46 literatūras avoti. Latviešu valodā. Cinka oksīds ir plaši pielietojams un viegli iegūstams materiāls ar izteiktām luminiscētām īpašībām. Bakalaura darbā tiek apskatītā pieejamā literatūra par porainā anodētā alumīnija oksīda (PAAO) un cinka oksīda nanostruktūru fotoluminiscenci. Eksperimentāla daļā tika aprakstītas un darba gaitā uz alumīnija pamatnes sintezētās PAAO matricas, uz kurām ar atomsļāņu nogulsnēšanu tika uznests cinka oksīds un, šķīdino…
Al2O3 apvalka ietekme uz ZnO nanovadu morfoloģisko stabilitāti pie paaugstinātas temperatūras ZnO/Al2O3/MoS2 heterostrukturētās kodola-apvalka nanova…
2021
Al2O3 apvalka ietekme uz ZnO nanovadu morfoloģisko stabilitāti pie paaugstinātas temperatūras ZnO/Al2O3/MoS2 heterostrukturētās kodola-apvalka nanovadu sistēmās. Ozols A., darba vadītājs Dr. phys., vadošais pētnieks (LU CFI) Poļakovs B. Bakalaura darbs, 34 lappuses, 42 attēli, 37 literatūras avoti, 1 pielikums. Latviešu valodā. Šajā bakalaura darbā tika pētīts, kā alumīnija oksīda pārklājums ietekmē cinka oksīda nanovadu morfoloģisko stabilitāti pie paaugstinātas temperatūrās, molibdēna trioksīda slāni mēģinot pārvērst par molibdēna disulfīdu sēra tvaikos. Cinka oksīda nanovadu sintēzi veica ar ķīmiskā tvaika transporta reakciju. Alumīnija oksīda pārklājums tika uzklāts uz nanovadiem izmant…
Kadmija sulfīda nanovadu virsmas pasivācija vides apstākļu izraisītas degradācijas samazināšanai
2021
Kadmija sulfīda nanovadu virsmas pasivācija vides apstākļu izraisītas degradācijas samazināšanai. Dipāne L., kursa darba vadītājs Dr. phys. Butanovs E. (LU CFI). Bakalaura darbs, 31 lappuse, 21 attēli, 3 tabulas, 30 literatūras avoti, 1. pielikums. Latviešu valodā. Darbā veikta CdS nanovadu sintēze ar tvaiks-šīdums-cietviela metodi un plānu metālu oksīdu pārklājumu veidošana uz to virsmas ar atomslāņu depozīcijas (ALD) metodi. Iegūtās nanostruktūras tika raksturotas, izmantojot skenējošo elektronu mikroskopu (SEM), transmisijas elektronu mikroskopu (TEM), enerģētiski dispersīvo rentgenstaru spektroskopiju (EDX) un rentgenstru difrakciju (XRD). Tika veikta divkontaktu ierīču izveidošana un v…
Failure of ProTaper rotary Ni-Ti instruments used by undergraduate students
2012
Objective: To evaluate the effect of number of uses, angle and radius of curvature and type of instrument on the fracture of ProTaper rotary instruments when used by undergraduate students. Study Design: Three hundred and seventy-six molars, with a total of 1114 root canals, extracted were instrumented by undergraduate students using ProTaper instruments according to the manufacturer´s recommendations. When fracture occurred, data were collected concerning the number of uses, type of instrument, level of fracture, angle and radius of curvature. ANOVA test were used to determine the influence of type of instrument in the incidence of instrument fracture. Logistic regression model was used to…
Comparison of the accuracy of intraoral digital impression system and conventional impression techniques for multiple implants in the full-arch edent…
2020
Background Several impression techniques, especially in combination with computer-aided design and computer-aided manufacturing (CAD/CAM), are used in increasing the accuracy of dental implantology and decreasing patient discomfort. The study was designed to examine the accuracy of the digital impression (DI) of multiple implants with an intraoral scanner (IOS) and compared with that of a conventional impression (CI). Material and methods Four dental implants were placed in teeth area #33, #36, #43 and 46# of the mandibular full-arch model. The implanted model was replicated by IOS and CI after fitting of scannable abutments over the implant screws. Then, a small hole was made on the scan r…
Perceived barriers to the provision of preventive care among dentists of Udaipur, India
2015
Aim: To investigate the practice-, patient- and dentist related barriers to the provision of preventive dental care as perceived by dentists of Udaipur city, Rajasthan, India. Settings and Design:- A cross sectional descriptive survey was conducted among 120 dentists of Udaipur city, Rajasthan. Material and Methods: Mean Content Validity Ratio (CVR) was calculated as 0.87 based on the opinions expressed by a panel of total six academicians. Cronbach's coefficient was found to be 0.88, which showed a high internal reliability of the questionnaire. The questionnaire consisted of demographic questions and 12 specific research questions. Statistical analysis used:- Student's t-test and ANOVA te…
Establishing the relative importance of sympatric definitive hosts in the transmission of the sealworm, Pseudoterranova decipiens: a host-community a…
2001
The importance of a given host to a particular parasite can be determined according to three different criteria: host preference, host physiological suitability and host contribution to transmission. Most studies on the sealworm Pseudoterranova decipiens have focussed on the latter factor, but few attempts have been made to develop a quantitative transmission model evaluating the relative importance of each host. The purpose of this study was to propose a flow-chart model to study sealworm transmission within a seal community. The model was applied to hypothetical data of four seal species acting as definitive hosts of P. decipiens sensu stricto in eastern Canada: harp seal Phoca groenlandi…
Analysis of fit on implants of chrome cobalt versus titanium frameworks made by cad / cam milling
2020
Background This study analyzed the degree of passive and vertical fit achieved in frameworks using either cobalt-chromium (Co-Cr) or titanium (Ti) implant-supported fixed partial dentures ( FPDs) fabricated with a CAD/CAM milling technique. Material and Methods 33 3-unit FDPs, 17 of Co-Cr metal alloy (test group) and 16 of Ti (control group), were manufactured with two implants by copy milled technology. Optical microscopy was used to measure passive fit (PF) and vertical fit (VF) in all frameworks. The PF was evaluated by using the Single Screw test and the VF with the screws tightened at 20 Ncm. Descriptive and inferential analysis were performed to evaluate statistically significant diff…
Uso secuencial de herramientas de control de calidad en procesos productivos: una aplicación en el sector agroalimentario = Sequential use of quality…
2014
<p>Las diferentes herramientas del Control Estadístico de Calidad proporcionan mejores resultados si su uso se lleva a cabo de manera secuencial, facilitando la detección de los puntos débiles del proceso productivo. Así, en el presente estudio se expone un método de trabajo en el que se utilizan, atendiendo a la necesidad en cada punto de la cadena de producción, algunas de dichas herramientas. Concretamente se propone el uso del diagrama de flujo, gráfico de Pareto, hojas de comprobación, gráficos de control (en este caso gráfico p y gráfico de media-recorrido), así como el análisis de la varianza (ANOVA). El procedimiento se aplica a una empresa del sector agroalimentario, interesa…