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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.
51

Soil-microbe-volatile organic compound (SMVOC) analysis and authentic science inquiry into gas chromatography for a general chemistry laboratory class

Ruhs, Christopher Vincent 06 August 2011 (has links)
Sound research and effective teaching are both essential to the progress of science. This thesis encompasses two studies to address the two needs: a multi-scale soil study designed to validate a novel soil biological characterization method; and a pilot pedagogical study designed to test the efficacy of authentic science inquiry into gas chromatography. The soil study relies on a comparison of six soils taken from the Bahamas and Michigan. The novel method, using soil-derived VOCs analyzed via gas chromatography-mass spectrometry (GC-MS), proved effective for resolving soils, as hypothesized, and may prove useful for analyzing soil biology rapidly and non-destructively in future studies. The pilot pedagogical study compares traditional recipe-style instruction with authentic science inquiry in an undergraduate chemistry laboratory class. Pre- and post-assessments of students’ conceptual understanding, retention of terms, and attitude revealed the hypothesized superior efficacy of authentic science inquiry over traditional recipe-style instruction.
52

The Economic Significance Study on the Volleyball Hall of Fame and Its Charitable Impressions

Xu, Feng 01 January 2012 (has links) (PDF)
Events and attractions can bring visitors and have economic impact and significance in the local areas. The measure and estimate of the economic impact and significance becomes a big concern for the organizers, governments and local residents. This study assessed the economic significance and impact of the Volleyball Hall of Fame and its related events in October 2009, and furthermore it examined its charitable impressions. The study first examined the demographic background of the visitors, and then followed the basic economic impact and significance assessment process proposed by Crompton and Stynes. The locals, casuals and time-switchers were identified, and then the study assessed the economic contributions in two dimensions: (1) the economic significance assessment including all the visitors, and (2) the typical economic impact assessment excluding the locals, casuals and time-switchers, and applied a conservative multiplier. Group sizes and the lengths of the stay were also examined to determine how they may also relate to the economic significance and impact assessment. Additionally the study assessed the charitable impressions by the visitors through a set of Likert scaled statements. The study found that, although the Volleyball Hall of Fame is a small-scale attraction, it did generate an economic contribution to the local community. Furthermore visitors had strong awareness of, and supported the Volleyball Hall of Fame’s participation in the non-profit charitable events, and the charitable impressions were identified as possible means to promote visitors' willingness to donate to the Volleyball Hall of Fame.
53

Fame and Latter-Day Saint Youth: Value Conflicts and the Interpretive Audience

Frey, Shellie M. 01 January 2001 (has links) (PDF)
Fame is a paradoxical issue: a phenomenon that is both embraced and shunned simultaneously in American culture and particularly within many religious institutions. Leaders of the Church of Jesus Christ of Latter-day Saints (LDS), for instance, discourage its members (particularly the youth) from seeking out fame as well as famous individuals as role models. Yet they also incorporate positive rhetoric about fame as well in terms of famous LDS people, landmarks or groups. Furthermore, various aspects of the LDS Church (worldwide televised conferences, widely distributed books written by Church leaders, etc.) are highly mediated, thus, integrated with a public venue that is heavily associated with establishing or perpetuating fame. Therefore, leaders themselves may also be considered famous.In light of the complex view of fame both in and out of the Church, this study explores the relationship between fame and religiosity of LDS (Mormon) youth and how they define and resolve value conflicts therein. The study uncovers themes about how LDS youth define fame, how they talk about it, how they tie religiosity into those conversations, and whom they consider famous and why. The research also explores both the positive and negative uses of fame in the lives of LDS youth, including what they are learning and emulating from those who are famous, as well as how they see the role of fame playing out in the Church.Through qualitative research incorporating a series of triads, in-depth one-on-one interviews and nonparticipant observation, results of this study revealed an active audience that not only reads against the media, but recognizes and acknowledges the media manipulation that can be found in fame. While these LDS youth both embrace and reject various aspects of fame as it relates to their individual lives, LDS religious fundamentals clearly lay a foundation upon which these youth establish their ideals about fame and whom they choose as role models. When these religious ideals collide with the realities of mediated fame, internal conflict arises. Religiosity then becomes the strategy these youth incorporate to resolve these conflicts. Conversely, the closer fame merges with the religious values of these individuals, the more justified fame becomes in their minds. Furthermore, the data demonstrate a strong tendency toward gendered views about fame and religiosity, particularly within the value conflicts and resolutions, although additional research is needed to determine its conclusiveness. Overall, the religiosity of these LDS youth was found to supercede the influence of fame as the guiding force in their lives.
54

Does media coverage of mass shootings contribute to copycats? : A systematic literature review

Ayele, Ida January 2021 (has links)
This thesis provides a systematic literature review in order to accumulate and analyze previous research concerning the role of mass media's coverage of mass shootings in regards to copycats. Previous research indicates mass shootings are crimes where perpetrators take inspiration from one another and subsequently imitate each other. The purpose of this study is to review previous research on this contagion phenomenon to distinguish if there is a correlation between media coverage of mass shooters and copycats based on empirical data. In order to obtain scientifically accurate conclusions to the research questions and the purpose of this thesis, a systematic literature review method has been implemented. The result shows that previous research indicates that there is a correlation between the mass media's coverage of mass shootings and acts of copycats. There are studies presented in this thesis that conclude that some mass shooters openly confess to seeking fame by carrying out a mass shooting and that they receive as much or more media coverage than household celebrities at the time of the shootings. This thesis also concludes that there is evidence to support that after the occurrence of a mass shooting there is an average increase in the probability that another mass shooting takes place within the following 12 days. These findings support identified statistical trends in previous research in the field.  In conclusion, it is of most importance that the media reports responsibly on mass shootings since the implications of the detailed description of events, modus operandi, the firearm used and the amount of news coverage of mass shootings contribute to copycat mass shootings. Keywords: mass shootings, contagion, imitation, copycat, media coverage, fame seeking, mass media
55

A sustainability assessment for public buses : A multi-criteria approach / En hållbarhetsbedömning för offentliga bussar : En mulikriteriemetod

Magorrian, Eamon January 2018 (has links)
Many city planners, regional authorities and transport providers are tasked with the challenging job of selecting which type of public buses are suited to their location and priorities. The challenges of which are multidimensional in nature due to different policies to adhere to as well as economic, environmental and technical tradeoffs between options. The aim of this report was to provide decision support in the choice of powertrains and energy sources for buses in public transport systems. The methodology used was a multi-criteria analysis. The assessed transportation options include buses running on diesel, biogas, fatty acid methyl esters (FAME), hydro-treated vegetable oils (HVO), bioethanol as well as battery electric vehicles (BEVs) assessed separately as opportunity and overnight charging. Suitable bus solutions were broken into six key areas to be considered when selecting fleets. These involved economic, technical, reliability, infrastructure, environmental and social issues. The economic considerations highlighted: the cost of ownership and the market share of vehicles. Vehicle performance considerations included: the range/refuel time of a vehicle. Considerations involved in delivery reliability were: national energy security, whether there was a short-term backup fuel as well as current and future policy support. Another consideration regarding infrastructure was: the required level of change required. Regarding environment and energy, considerations of merit involved: well-to-wheel greenhouse gas reductions, air pollution in relation vehicle regulations, noise levels, nutrient recyclability as well as associated resource impacts. The social considerations were determined as: public opinion and job creation. From the compiled results assessing each criterion the grading matrix suggested it was biogas buses followed closely by HVO buses that scored the best. Weighted results were also conducted, emphasizing the most important criteria according to surveyed stakeholders which resulted in HVO and Biogas again performing the best. / Många stadsplanerare, regionala myndigheter och transportleverantörer har uppgift att utföra det utmanande arbetet med att välja vilken typ av offentliga bussar som passar deras läge och prioriteringar. Utmaningarna är multidimensionella på grund av olika politikområden för att följa såväl ekonomiska, miljömässiga som tekniska avvägningar mellan alternativ. Syftet med denna rapport var att ge beslutsstöd när det gäller val av elmotorer och energikällor för bussar i kollektivtrafiksystemen. Metoden som använts var en analys av flera kriterier. De bedömda transportalternativen inkluderar bussar som körs på diesel, biogas, fettsyrametylestrar (FAME), vattenbehandlade vegetabiliska oljor (HVO), bioetanol samt batteridrivna fordon (BEV) som bedömts separat som möjlighet och över natten laddning. Lämpliga busslösningar delades upp i sex nyckelområden som ska beaktas vid val av flottor. Dessa involverade ekonomiska, tekniska, tillförlitliga, infrastrukturella, miljömässiga och sociala frågor. Ekonomiska överväganden framhävs: ägandekostnader och marknadsandelar för fordon. Fordonets prestanda överväganden inkluderade: fordonets räckvidd / tankningstid. Överväganden som berörs av leveranssäkerhet var: nationell energisäkerhet, om det fanns ett kortsiktigt backupbränsle samt nuvarande och framtida politiskt stöd. En annan hänsyn till infrastrukturen var: den nödvändiga förändringsnivån. När det gäller miljö och energi var överväganden om meriter involverade: bränslesänkningar på vägen mot växthus, luftförorening i förhållande till fordonsbestämmelser, bullernivån, återvinningsförmåga för näringsämnen samt tillhörande resurskonsekvenser. De sociala övervägandena bestämdes som: allmän åsikt och skapande av arbetstillfällen. Från de sammanställda resultaten som bedömde varje kriterium noterades att biogasbussar, som följdes noggrant av HVO-bussar, gjorde det bästa enligt graderingsskalmatrisen. Viktiga resultat genomfördes också, med betoning på de viktigaste kriterierna enligt de undersökta intressenterna, vilket resulterade i att HVO och Biogas återigen utför de bästa.
56

PROFILE AND NITROGEN DYNAMICS OF MICROBIAL COMMUNITIES IN AGRICULTURAL INTERCROPPING SHRUB-CROP SYSTEMS OF SENEGAL

LATTIN, ESTHER E. January 2017 (has links)
No description available.
57

Alternativa Drivmedel som Enhetsdrivmedel / Alternative fuel as a single fuel

Schedin, Niclas January 2013 (has links)
Fossila drivmedel står idag för en överlägsen majoritet av den totala användningen av drivmedel som dagligen förburkas. Alternativ till de fossila drivmedlen krävs för att säkerställa tillgång i framtiden. Försvarsmakten har fått uppdrag från regeringen att utforska möjligheten att övergå till att driva sina fordon på förnyelsebara bränslen.Militära organisationer strävar efter ett enhetsdrivmedel, alltså ett gemensamt drivmedel som driver samtliga fordon och enheter. Största anledningen är den förenklade logistik som kan uppnås om endast ett drivmedel används.Detta arbete har sökt efter ett alternativt drivmedel som skulle kunna användas som enhetsdrivmedel inom Försvarsmakten. Detta för att lösa problematiken med att både byta till ett förnyelsebart drivmedel och ett enhetsdrivmedel i samma fas.Slutsatserna som dragit i detta arbete är att FT-bränslen har potential att användas som enhetsdrivmedel ur ett tekniskt perspektiv. Den höga flampunkt som FT-bränslen har skulle kunna innebära att även sjöfarkoster kan använda samma drivmedel som mark- och luftfarkoster. Dock saknas i dagsläget tillräcklig tillgänglighet och framställningen är i utvecklingsfasen. / Fossil fuels currently account for the vast majority of the total amount of fuel that isconsumed globally every day. Alternatives to fossil fuels are needed to ensuresufficient supply in the future. The Swedish Armed Forces have been tasked by theGovernment to investigate and examine the possibility of operating their vehicles onrenewable fuels.Military organizations strive for the use of a single fuel concept. A single fuel conceptmeans that only one kind of fuel is used in all vehicles and machines. The majorreason for this is the simplified logistics that can be achieved if only one fuel is used.This paper has sought an alternative fuel that can also be used as a single fuel in theSwedish Armed Forces. In order to solve the problem of changing to a renewable andto a single fuel in one single step.The main conclusion drawn in this paper is that Fischer-Tropsch fuels have thepotential to be a single fuel from a technical perspective. The high flashpoint ofFischer-Tropsch fuels could mean that they might also be used in navy vessels.However, there is currently insufficient availability and production is in thedevelopment stages.
58

Diagnostika perspektivních elektroizolačních kapalin / Diagnostics of the perspective insulating liquids

Spohner, Milan January 2011 (has links)
This work deals with the classification and diagnosis of electrical insulating liquids. Furthermore, the theoretical part describes the mathematical and physical principles of these liquids. The automated workplace was compiled with development environment VEE Pro for measurement of viskosity and control thermostat medingen and modifiable components for measuring complex permittivity in the frequency range. In the experimental part was carried out measurements of selected material parameters, investigated the effect of difficult conditions and made the mathematical evaluation of physical phenomena.
59

An Investigation of the Donation Willingness of the Donators of the Non-Profit Organizations: A Comparison Between Religious and Non-religious Organizations

Hsin, Jia-chen 22 June 2009 (has links)
Because of the diversity of the society,the contents of the service and production provided by the public department (Government) and the private department (Business) can not fit the present and future needs. Based on the failures of the functions of the society and the government,NPO or NGO is flourishing to make up for the insufficiency of the two departments. There is a vigorous development of NPOs in Taiwan since 921 earthquake,and the numbers of NPOs rise steeply.As to NPOs,it is very critical to understand the donation willingness of the donators on the situation of limited society resources and private donations. The goals of the research are to discuss the donation willingness of the donators of the NPOs including the personalities, motives, religious beliefs of the donators,the fame of NPOs,the extent of expositions of information and the usage of the donation.And then probe the causes of the donation willingness of the donators. The goals of the rsearch are as following: 1.To probe the recognition of the NPOs managers,volunteers and donators to influence the donation willingness of the donators in Kaohsiung district. 2.To analyze the factors that influence the donators of the NPOs in Kaohsiung district. 3.To provide the suggestions to the managers of the NPOs in Kaohsiung district.
60

Autoxidação de ésteres metílicos de ácidos graxos: estudo teórico-experimental / Auto-oxidation of fatty acid methyl esters: theoretical-experimental study

Albuquerque, Anderson dos Reis 05 September 2010 (has links)
Made available in DSpace on 2015-05-14T13:21:49Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3150509 bytes, checksum: cf7874482452595653f1051a5680bdf0 (MD5) Previous issue date: 2010-09-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, computational chemistry calculations and thermal analysis experiments were performed in order to determine the oxidative stability of four fatty acid methyl esters (stearate, oleate, ricinoleate and linoleate), whose fatty chains may be inserted in oils and biodiesel. In the computational chemistry investigation the sequence of stabilities, based on the dissociation energy of the C-H bond was: C18:2 < C18:1 < C18:1;12-OH < C18:0, for the B3LYP 6-31G(d) and MP2 6-311++G(2d,p); and C18:2 < C18:1;12-OH < C18:1 < C18:0, for the B3LYP 6-311++G(2d,p). The spin density analysis allowed stating that the ricinoleate hydroxyl does not act as a pro-oxidizing, as the radicals formed in C-12 or OH are not stabilized by the unsaturation in C9, showing, thus, the behavior of a secondary alkyl alcohol in relation to these sites, whereas their allylic hydrogen display an energy similar to the oleate hydrogens. In the experimental investigation carried out TG, it was possible to observe the formation of hydroperoxides by means of the mass gain in an oxygen atmosphere for oleate, linoleate and ricinoleate, but only volatilization for the stearate. In this investigation, a small heating rate (2 ºC/min) was utilized. The kinetic calculations based on PDSC, in the dynamic and isothermal modes showed that the oxidation susceptibility is quite dependent of temperature, atmosphere and the method employed, being more critical in relation to the methyl ricinoleate. In the dynamic mode, in an air atmosphere at 110ºC, the relative susceptibility was 1 : 17 : 17 : 226 (C18:0 : C18:1 : C18:1;12-OH : C18:2). In an O2 atmosphere this proportion was 1 : 11 : 1 : 102. In the isothermal mode PDSC, at the same temperature, the proportion was 1 : 1230 : 1585 : 23001 in an air atmosphere, and 1 : 33 : 40 : 445 in an O2 atmosphere. Performing a structure/property relationship, the oxidation temperature determined at a heating rate of 10 ºC/min was shown to be strongly correlated with the BDE (C-H) obtained by DFT and MP2, confirming the relationship between the first exothermic event of PDSC in the dynamic mode and the C-H bond strength. Therefore, PDSC is shown as a accelerated testing technique able to determine the true oxidative stability of lipids, as it supplies information on the rate controlling step of auto-oxidation (L-H + R1● → L● + R1-H), whereas the Rancimat method does not supply such information. Ternary ester blends were made and their oxidative stabilities were assessed by means of PDSC in a synthetic air atmosphere. Four equations were obtained with high linear correlation coefficients (R2 > 0.98). A biodiesel representation model was also developed, expressing its main oxidation sites and molecular descriptors for several physico-chemical properties. This representation is expressed by the molecular formula Ca Hb H*c Hd** He***(O2)f (0H)g and shows as one of its advantages the easy display of biodiesel data, what makes more evident the study of structure/property relationship. Its application for the four FAME s and twenty-three blends allowed determining the oxidation temperature (OT) in an air atmosphere, based on the descriptors for allylic hydrogen (H*) and bis-allylic hydrogens (H**). From such model a program in language C was elaborated, whose input is the FAME mole fraction and whose output is the OT in a synthetic air atmosphere. Keywords: Auto-oxidation, FAME (fatty acid methyl esters), Biodiesel, PDSC, DFT. / Nesse trabalho, cálculos de química computacional e experimentos de análise térmica foram realizados para determinar a estabilidade oxidativa de quatro ésteres metílicos de ácidos graxos (estearato, oleato, ricinoleato e linoleato), cuja cadeia graxa pode estar inserida em óleos e biodiesel. Na investigação por química computacional a seqüência de estabilidade com base na energia de dissociação da ligação C-H foi: C18:2 < C18:1 < C18:1;12-OH < C18:0, para o B3LYP 6-31G(d) e MP2 6-311++G(2d,p); e C18:2 < C18:1;12-OH < C18:1 < C18:0, para o B3LYP 6-311++G(2d,p). A análise da densidade de spin permitiu afirmar que a hidroxila do ricinoleato não age como pró-oxidante, pois os radicais formados no C-12 ou OH não são estabilizados pela insaturação no C9, comportando-se, portanto, como um álcool alquílico secundário em relação a esses sítios, enquanto que seus hidrogênios alílicos possuem energia próxima aos do oleato. Na investigação experimental por TG foi possível observar a formação dos hidroperóxidos através do ganho de massa em atmosfera de oxigênio para o oleato, linoleato e ricinoleato, mas apenas volatilização para o estearato. Para tanto, uma pequena taxa de aquecimento (2 ºC/min) foi utilizada. Os cálculos cinéticos obtidos por PDSC nos modo dinâmico e isotérmico mostraram que a susceptibilidade relativa à oxidação é bastante dependente da temperatura, da atmosfera e do método empregados, sendo mais crítica em relação ao ricinoleato de metila. No modo dinâmico, em atmosfera de ar à 110ºC, a susceptibilidade relativa foi de 1 : 17 : 17 : 226 (C18:0 : C18:1 : C18:1;12-OH : C18:2). Em atmosfera de O2 essa proporção foi de 1 : 11 : 1 : 102. Na PDSC modo isotérmico nessa mesma temperatura a proporção foi de 1 : 1230 : 1585 : 23001 em atmosfera de ar, e 1 : 33 : 40 : 445 em atmosfera de O2. Fazendo uma relação estrutura-propriedade, a temperatura de oxidação na taxa de aquecimento de 10 ºC/min mostrou-se bastante correlacionada com a BDE (C-H) obtidas por DFT e MP2, confirmando a relação entre o primeiro evento exotérmico da PDSC no modo dinâmico e a força da ligação C-H. Nesse sentido, a PDSC apresenta-se como a técnica de ensaio acelerado capaz de determinar a verdadeira estabilidade oxidativa de lipídeos, pois fornece informações sobre a etapa contraladora da velocidade de autoxidação (L-H + R1● → L● + R1-H), enquanto que o método Rancimat não fornece essa informação. Foram realizadas misturas ternárias dos ésteres e verificadas suas estabilidades oxidativas por PDSC em atmosfera de ar sintético. Quatro equações foram obtidas com elevada correlação linear (R2 > 0.98). Foi desenvolvido também um modelo de representação do biodiesel expressando seus principais sítios de oxidação e descritores moleculares para diversas propriedades físico-químicas. Essa representação é dada pela fórmula molecular Ca Hb H*c Hd** He***(O2)f (0H)g e tem como uma das vantagens a simplificação de apresentação dos dados para biodieseis, o que torna mais palpável o estudo de relação estrutura-propriedade. Sua aplicação para os quatro FAMEs e vinte e três misturas permitiu determinar a temperatura de oxidação (OT) em atmosfera de ar com base nos descritores para hidrogênios alílicos (H*) e bis-alílicos (H**). A partir desse modelo foi elaborado um programa em linguagem C, tendo como dados de entrada a fração molar dos FAMEs e como saída a OT em atmosfera de ar sintético.

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