1,998 research outputs found
A grammar of Hamar : a South Omotic language of Ethiopia
No full text
This study is the first-ever attempt at a comprehensive grammatical description of Hamar, a language spoken in South West Ethiopia by approximately 46.500 people. The study is based on 9 months of fieldwork carried out between 2012 and 2014 in Hamar territories. Language data was gathered from 14 native speakers in Hamar villages, and it amounts to 50 texts of varying lengths and genres. The grammar investigates the phonology, the morphology, the syntax and some pragmatic and discourse related features of Hamar and it is organized in 13 chapters followed by three appendices: appendix A and B consist of a selected lexicon of circa 1400 entries, appendix C includes three annotated Hamar texts.
Hamar is a fascinating language and it has revealed unique typological features: the noun classification system of Hamar for instance is a rare example of ʻnon-fixedʼ gender system, i.e. a system in which gender is not an inherent property of nouns, but optional. The grammar is of interests to typologists but also to linguists interested in comparative Afro-Asiatic studies: the grammar offers an overview of the classificatory issue of Hamar and South Omotic languages, and it includes an updated comparative list of South Omotic lexicon.
Labex ASLAN, Université de Lyon (Agence Nationale de la Recherce)Language Use in Past and Presen
Spectral reflectance characteristics of the Hamar Laghdad hydrothermal sequence, Morocco: Implications for the methane origin on Mars
No full textWe analyze and discuss reflectance spectra of carbonate rocks from the Hamar Laghdad area (Morocco), where evidences of interactions with hydrothermal, and, in some cases, methane enriched fluids derived from underlying volcanoclastic rocks, are reported in the literature. Deconvolution of the rock spectra into a sum of Gaussians, using MGM, resolved a number of both vibrational and electronic absorption features, mainly assigned to CO32-, Al-OH, and Fe2+, Fe3+, Cu, CF interaction processes, respectively. The associations of these absorption bands are exhaustive descriptions of the rock spectral properties. A spectral model of the Hamar Laghdad carbonate sequence was therefore delineated, based on the integration of these absorption band associations with XRF and Mössbauer analyses of the rock samples. The model involves: pure limestones and dolostones, limestone with iron carbonates, mixed carbonate and Al-silicate impure limestones, limestones with iron sulfides. The model points out the complexity of the spectral characteristics of rocks that underwent hydrothermal and partly methanogenic processes, but also suggests an alternative geologic scenario plausible for possible methanogenic activity in the Mars geologic past
Spectral reflectance characteristics of the Hamar Laghdad hydrothermal sequence, Morocco: Implications for the methane origin on Mars
No full textWe analyze and discuss reflectance spectra of carbonate rocks from the Hamar Laghdad area (Morocco), where evidences of interactions with hydrothermal, and, in some cases, methane enriched fluids derived from underlying volcanoclastic rocks, are reported in the literature. Deconvolution of the rock spectra into a sum of Gaussians, using MGM, resolved a number of both vibrational and electronic absorption features, mainly assigned to CO32−, Al–OH, and Fe2+, Fe3+, Cu, CF interaction processes, respectively. The associations of these absorption bands are exhaustive descriptions of the rock spectral properties. A spectral model of the Hamar Laghdad carbonate sequence was therefore delineated, based on the integration of these absorption band associations with XRF and Mössbauer analyses of the rock samples. The model involves: pure limestones and dolostones, limestone with iron carbonates, mixed carbonate and Al-silicate impure limestones, limestones with iron sulfides. The model points out the complexity of the spectral characteristics of rocks that underwent hydrothermal and partly methanogenic processes, but also suggests an alternative geologic scenario plausible for possible methanogenic activity in the Mars geologic past
Comparison of Control Algorithms for an Inverted Pendulum
No full textABSTRACT\ud
COMPARISON OF CONTROL ALGORITHMS FOR AN INVERTED\ud
PENDULUM\ud
by\ud
?? Trisha Annie Hamar 2009\ud
Master of Science in Electrical and Computer Engineering\ud
Electronic Engineering Option\ud
California State University, Chico\ud
Fall 2009\ud
A Proportional, Integral and Derivative controller, also known as a PID\ud
controller, was designed for a free-range inverted pendulum. The PID algorithm was\ud
compared to the Linear Quadratic Regulator, or LQR, on the inverted pendulum to\ud
quantify the merits of each algorithm based on performance. This study will present the\ud
controller designs, simulations, code and hardware implementation, as well as the\ud
results.\ud
The PID algorithm is a tuning process where the user adjusts gain values as\ud
needed. The LQR algorithm is a traditional digital control theory that utilizes state\ud
space design and weighting matrices. Simulations were performed on MATLAB and\ud
Simulink. Each algorithm was implemented in C programming into the ARM processor.\ud
Primary comparisons included ease of implementation, the complexity of the code, and\ud
the overall performance of the system.\ud
The PID algorithm performed better in trials and was easier to implement in\ud
the C programming language. The LQR algorithm was based on a linearized system and\ud
was not able to handle nonlinear components such as gear backlash.\ud
The results suggested that if the system were built on a linear guide rail\ud
instead of a free-range vehicle, the inverted pendulum may have exhibited better\ud
performance. A linear rail would greatly reduce any external disturbances or noise.\ud
This report will serve as an informational and instructional guide for future students who\ud
wish to pursue an inverted pendulum design.CSU, Chic
Experimental control strategies reducing the fungicide input at a practical scale
No full textPhytophthora infestans is the most devastating disease in potato cultivation. Chemical control is necessary to ensure a healthy crop. At the same time Dutch governmental policy asks for a reduction of the environmental impact of potato late blight control by 75% in 2012 as compared to 1996-1998. The aim of the experiments was to compare Decision Support Systems with different approaches to blight risk management for their ability to reduce the fungicide input without compromising control efficacy. Considerable savings, up to 81% when compared to weekly, full dose rate, spray schedules, can be achieved by using information on cultivar resistance, length of the critical period and disease pressure to decide whether or not to spray. The subroutine calculating the potential for viable transport of spores is only effective on resistant varieties as the threshold was exceeded with every critical period on less resistant cultivars. Implications of the experimental control strategies for agricultural practise are discusse
Epiphytic diatoms of the Tisza River, Kisköre reservoir and some oxbows of the Tisza River after the cyanide and heavy metal pollution in 2000
No full textThe Tisza River is a large tributary of the Danube River. The largest reservoir of the river is the Kisköre reservoir, and there are furthermore a great number of oxbows in the vicinity of the river. In February and early spring 2000 serious amounts of cyanide and heavy metal pollution were spilled into the Tisza River. The Kisköre Reservoir of the Tisza was less polluted than the river itself. However, the four oxbows investigated were flooded by the Tisza River in April 2000. Epiphytic diatom samples were taken in February and October 2000 along the Tisza River, in November and December 2000 at the Kisköre Reservoir and in May and July 1996, October 2000 and June 2001 at the four Tisza oxbows. The aims of this study were to obtain preliminary data about the species composition of the attached diatoms of these waters, to evaluate the impact of the pollution on epiphytic diatoms and to evaluate the natural protection value of these waters. Epiphyton of the Tisza River was dominated by Achnanthidium minutissimum, Amphora pediculus, Cocconeis placentula, Diatoma moniliformis in February and by Achnanthidium minutissimum and several Nitzschia spp. in October. A number of teratological frustules were observed. In the Kisköre reservoir, Amphora pediculus, Cocconeis pediculus, C. placentula, Cyclotella meneghiniana, Gomphonema angustum, Nitzschia dissipata were dominant. In 1996 Staurosira, Staurosirella and Navicula species dominated in the oxbows, whereas in 2000 Aulacoseira distans, Achanthidium minutissimum and Nitzschia spp. became dominant. Based on results from the literature, we are of the opinion that the characteristic Achnanthidium minutissimum - Nitzschia spp. dominance of the Tisza River and the oxbows is partly due to the heavy metal pollution. A number of endangered species, two new elements for the Hungarian diatom flora - Navicula austrocollegarum and Navicula streckerae - and two probably invasive species, Diadesmis confervacea and Didymosphenia geminata were found
An in situ XAS study of high surface-area IrO2 produced by the polymeric precursor synthesis
No full textIridium oxide powders with a surface area of more than 1 m2 g-1 (4 m2 g-2 from the H-UPD charge) and iridium-oxide crystallites less than 10 nm across were synthesized by heat treating gels formed from citric acid, ethylene glycol and dihydrogen hexachloroiridate(iv) in air. The characteristics of the resulting material was found to be strongly dependent on the heat-treatment step in the synthesis. A single heat-treatment of the gel resulted in a material with a substantial fraction of elemental iridium metal, i.e. iridium in oxidation state zero (Ir0). Post-synthesis modification of the powder by potential cycling resulted in oxidation peaks consistent with the conversion of the metal phase to iridium oxide. Linear combination of the near-edge part of the X-ray absorption data (X-ray absorption near-edge spectroscopy, XANES) collected in situ during potential cycling and an analysis of the extended X-ray fine-structure (EXAFS) part of the spectrum showed that the overall metal fraction was not significantly affected by the cycling. The oxidation of the metal phase is therefore limited to a thin layer of oxide at the metal surface, and a significant part of the iridium is left inactive. A modification of the heat treatment procedure of the sample resulted in iridium oxide containing only insignificant amounts of elemental iridium metal.</p
Sustainability Reporting in the North American Tourism Industry: Research Paper
No full textPeer reviewedGreg McCullu
All'opposto. Due interventi sulle rovine di Hamar (Norvegia)
No full textStarting from the second half of the XXth century, the area located on the Domkirkeodden cape in Norway was the subject of various interventions in order to protect the exposed archaeological remains. The most famous of these interventions is the new museum (1967-1979) designed by Sverre Fehn. Equally interesting but definitely less investigated by the critics are the two pavilions that Fehn designed between 2001 and 2005. The paper focuses on these two pavilions in “opposition” to the later project that, at the end of the ’90, the Norwegian studio Lund & Slaatto has realized to protect the remains of the nearby Medieval cathedral. The relation with history, the materials and the role attributed to the protective roof make these two case studies emblematic to understand the paths that Fehn’s architectural poetry followed
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