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Single-Step Treatment of 2,4-Dinitrotoluene Via Zero-Valent Metal Reduction and Chemical OxidationThomas, J. Mathew 09 December 2006 (has links)
Many nitroaromatic compounds (NACs) are considered toxic and potential carcinogens. The purpose of this study was to develop an integrated reductive/oxidative process for treating NAC contaminated waters. The process consists of the combination of zero-valent manganese or iron and a hydroxyl radical based treatment technique. Corrosion promoters were added to the contaminated water to minimize passivation of the metallic species. Water contaminated with 2,4-dinitrotoluen (DNT) was treated with the integrated process using a recirculating batch reactor. It was demonstrated that addition of corrosion promoters to the contaminated water enhanced the rate of reaction of 2,4-DNT with zero-valent iron or manganese. Results showed that iron provided greater reduction of 2,4-DNT than manganese. Chemical oxidation was used to mineralize the reduction products. The degree of mineralization was measured analyzing the samples for total organic carbon and nitrates. A proposed reaction and corrosion mechanisms and rate expressions were developed during the course of the study.
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On zeros of cubic L-functionsXia, Honggang 03 August 2006 (has links)
No description available.
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Being Sherlock Holmes Can we sense empathy from a brief sample of behaviourWu, W., Sheppard, E., Mitchell, Peter 04 June 2020 (has links)
Yes / Mentalizing (otherwise known as ‘theory of mind’) involves a special process that is adapted for predicting and explaining the behaviour of others (targets) based on inferences about targets’ beliefs and character. This research investigated how well participants made inferences about an especially apposite aspect of character, empathy. Participants were invited to make inferences of self‐rated empathy after watching or listening to an unfamiliar target for a few seconds telling a scripted joke (or answering questions about him/herself or reading aloud a paragraph of promotional material). Across three studies, participants were good at identifying targets with low and high self‐rated empathy but not good at identifying those who are average. Such inferences, especially of high self‐rated empathy, seemed to be based mainly on clues in the target's behaviour, presented either in a video, a still photograph or in an audio track. However, participants were not as effective in guessing which targets had low or average self‐rated empathy from a still photograph showing a neutral pose or from an audio track. We conclude with discussion of the scope and the adaptive value of this inferential ability.
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Prediction and Measurement of Thermal Exchanges within PyranometersSmith, Amie Michelle 10 November 1999 (has links)
The Eppley Precision Spectral Pyranometer (PSP) is a shortwave radiometer that is widely used in global networks to monitor solar irradiances at the earth's surface. Within the instrument, a blackened surface is in intimate thermal contact with the hot junction of a thermopile. The cold junction of the thermopile communicates thermally with the large thermal capacitance of the instrument body, which acts as a heat sink. Radiation arrives at the blackened surface through one or two hemispherical dome-shaped filters that limit the instrument response to the solar spectrum. The voltage developed by the thermopile is then interpreted in terms of the incident irradiance.
Measurements taken with the pyranometer are compared with results from theoretical models. Discrepancies between model results and measurements are used to isolate inaccuracies in the optical properties of the atmosphere used in the models. As the accuracy of the models increases, the reliability of the measurements must be examined in order to assure that the models keep up with reality. The sources of error in the pyranometer are examined in order to determine the accuracy of the instrument.
Measurements obtained using the pyranometer are known to be influenced by environmental conditions such as ambient temperature, wind, and cloud cover [Bush, et al., 1998]. It is surmised that at least some of the observed environmental variability in these data is due to parasitic thermal exchanges within the instrument [Haeffelin et al., 1999]. Thermal radiation absorbed and emitted by the filters, as well as that reflected and re-reflected among the internal surfaces, influences the net radiation at the detector surface and produces an offset from the signal that would result from the incident shortwave radiation alone. Described is an ongoing effort to model these exchanges and to use experimental results to verify the model.
The ultimate goal of the work described is to provide reliable protocols, based on an appropriate instrument model, for correcting measured shortwave irradiance for a variable thermal radiation environment. / Master of Science
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Charging Forward: The Impact of State Incentives on Electric Vehicle Adoption and Emission Reduction TargetsO'Malley, Eamon January 2024 (has links)
Thesis advisor: John J. Piderit / This paper examines state and county-exclusive incentives on battery electric vehicle (BEV) registration in the United States. Using two main methods, a differences-in-differences method and a sigmoidal growth rate equation, I examine the impact of non-federal incentives on the total amount of electric vehicles between 2017 and 2022, as well as estimate the years that each state will reach its net-zero goals for carbon emissions in the transportation sector. I hope to provide a deeper understanding of the effectiveness of incentive policy, based on differing levels of incentive policy between regions, in order to best increase electric vehicle adoption in a cost-effective method. In addition, I hope that my estimates of net-zero projections will serve as a beneficial comparison to track states’ respective progress towards sustainable energy in vehicles. These findings can be used to assist policymakers in determining appropriate BEV adoption policies based on regional consumer demographics and needs, as well as visualize a timeline for the next century of rapid electric vehicle growth. / Thesis (BA) — Boston College, 2024. / Submitted to: Boston College. Morrissey School of Arts and Sciences. / Discipline: Economics. / Discipline: Departmental Honors.
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Sediment Oxygen Demand KineticsOlinde, Lindsay 24 May 2007 (has links)
Hypolimnetic oxygen diffusers increase sediment oxygen demand (SOD) and, if not accounted for in design, can further exacerbate anoxic conditions. A study using extracted sediment cores, that included both field and laboratory experiments, was performed to investigate SOD kinetics in Carvin's Cove Reservoir, a eutrophic water supply reservoir for Roanoke, Virginia. A bubble-plume diffuser is used in Carvin's Cove to replenish oxygen consumed while the reservoir is thermally stratified. The applicability of zero-order, first-order, and Monod kinetics to describe transient and steady state SOD was modeled using analytical and numerical techniques. Field and laboratory experiments suggested that first-order kinetics characterize Carvin's Cove SOD. SOD calculated from field experiments reflected diffuser flow changes. Laboratory experiments using mini-diffusers to vary dissolved oxygen concentration and turbulence were conducted at 4°C and 20°C. Similar to field observations, the laboratory results followed changes in mini-diffuser flow. Kinetic-temperature relationships were also observed in the laboratory experiments. A definitive conclusion could not be made on the broad applicability of first-order kinetics to Carvin's Cove SOD due to variability within field experiments. However, in situ experiments are underway that should assist in the overall understanding of the reservoir's SOD kinetics. / Master of Science
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Visuo-Haptic recognition of daily-life objects : a contribution to the data scarcity problem / Reconnaissance visio-haptique des objets de la vie quotidienne : à partir de peu de données d'entraînementAbderrahmane, Zineb 29 November 2018 (has links)
Il est important pour les robots de pouvoir reconnaître les objets rencontrés dans la vie quotidienne afin d’assurer leur autonomie. De nos jours, les robots sont équipés de capteurs sophistiqués permettant d’imiter le sens humain du toucher. C’est ce qui permet aux robots interagissant avec les objets de percevoir les propriétés (telles la texture, la rigidité et la matière) nécessaires pour leur reconnaissance. Dans cette thèse, notre but est d’exploiter les données haptiques issues de l’interaction robot-objet afin de reconnaître les objets de la vie quotidienne, et cela en utilisant les algorithmes d’apprentissage automatique. Le problème qui se pose est la difficulté de collecter suffisamment de données haptiques afin d’entraîner les algorithmes d’apprentissage supervisé sur tous les objets que le robot doit reconnaître. En effet, les objets de la vie quotidienne sont nombreux et l’interaction physique entre le robot et chaque objet pour la collection des données prend beaucoup de temps et d’efforts. Pour traiter ce problème, nous développons un système de reconnaissance haptique permettant de reconnaître des objets à partir d'aucune, de une seule, ou de plusieurs données d’entraînement. Enfin, nous intégrons la vision afin d’améliorer la reconnaissance d'objets lorsque le robot est équipé de caméras. / Recognizing surrounding objects is an important skill for the autonomy of robots performing in daily-life. Nowadays robots are equipped with sophisticated sensors imitating the human sense of touch. This allows the recognition of an object based on information ensuing from robot-object physical interaction. Such information can include the object texture, compliance and material. In this thesis, we exploit haptic data to perform haptic recognition of daily life objects using machine learning techniques. The main challenge faced in our work is the difficulty of collecting a fair amount of haptic training data for all daily-life objects. This is due to the continuously growing number of objects and to the effort and time needed by the robot to physically interact with each object for data collection. We solve this problem by developing a haptic recognition framework capable of performing Zero-shot, One-shot and Multi-shot Learning. We also extend our framework by integrating vision to enhance the robot’s recognition performance, whenever such sense is available.
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Förädling av textil- En studie om att skapa mervärde av skänkta kläder och textilier / Refinement of TextileSöderström, Mia, Bumar, Ines January 2011 (has links)
Våren 2011 beslutade Röda Korset i Sverige att sluta skicka skänkta kläder som bistånd till katastrofområden. Röda Korset ställdes nu inför frågan vad de ska göra med de skänkta klä-derna för att omvandla dem till en resurs.Uppdraget var att i samarbete med Zäntrumprojektet och Röda Korsets secondhandbutik Ku-pan förädla de skänkta kläderna på ett miljövänligt sätt. Tanken är att Zäntrumprojektet ska sy om de skänkta kläderna till nya produkter som sedan ska säljas i secondhandbutiken Kupan.Syftet med den här uppsatsen är att finna ett sätt att förädla de skänkta kläderna och skapa nya produkter av dem. Vidare ska de skänkta kläderna skapa bättre resurser till Röda Korset som de kan tillgodogöra sig i sitt välgörenhetsarbete. Produkterna ska vara skapade på ett sådant sätt att de avger minsta möjliga avfallsmängd, främjar hållbar utveckling samt är attraktiva för Röda Korsets secondhandbutiks kunder. Frågeställningarna som den här rapporten följer är vilka produkter tillverkade av skänkta kläder som konsumenter är intresserade av att köpa. Hur arbetsgången och sömnadsbeskrivningen för produkterna bör se ut och hur minsta möjliga avfallsmängd kan uppnås. Hur tillvägagångssättet i en industriell textilproduktion kan ap-pliceras på Röda Korset och Zäntrumprojektets småskaliga produktion.Rapporten resulterade i att tre olika produkter inom kategorin hemtextil togs fram. Valet av produkter baserades på en marknadsundersökning samt en utformad kravspecifikation. De tre produkter som valdes ut var pennfodral, sittdyna och prydnadskudde. Vidare togs tre söm-nadsbeskrivningar fram för produkterna för vägledning vid tillverkning. För att uppnå minsta möjliga avfallsmängd vid tillverkningen av produkterna tillämpades Zero-waste principen. Förslag togs även fram gällande vilka förändringar Zäntrumprojektet skulle behöva utföra för att ta till sig tillvägagångssättet i en industriell produktion.Röda Korset behöver se över samarbetet mellan Zäntrumprojektet och secondhandbutiken Kupan. Båda grupperna har stor potential och möjligheter finns för ett framgångsrikt samarbe-te dem emellan.In the spring of 2011 the Red Cross in Sweden decided to stop sending donated clothing assis-tance to disaster areas. The Red Cross was now faced with the question what to do with the donated clothes, and how to convert them to a resource.The mission was to cooperate with Zäntrumprojektet and the Red Cross secondhand store Ku-pan and refine the donated clothes in an environmentally friendly manner. The idea is that Zäntrumprojektet will sew new products from the donated clothes which will then be sold in the secondhand store Kupan.The purpose of this paper is to find a way to process the donated clothes and create new prod-ucts from them so that they create better facilities to the Red Cross as they can assimilate into its charitable work. Products must be created in such a way that they emit the least possible amount of waste, promoting sustainable development and are attractive to the Red Cross se-condhand stores customers. The questions that this report follows are which type of products made from donated clothes are consumers interested in purchasing. How working time and sewing instructions of the products should look like and how the minimum amount of waste can be achieved. How the approach of an industrial textile production can be applied to the Red Cross and Zäntrumprojektets small-scale production.The report led to that three different products was developed in the category home textiles. The choice of products was based on a market survey and a design specification. The three products selected were pencil case, seat cushions and decorative pillow. Furthermore, three sewing instructions were presented for the products to guide the production. To achieve the smallest possible amount of waste in the manufacture of the products we worked after the Zero-waste principle. Proposals were also submitted regarding the changes Zäntrumprojektet would have to perform in order to embrace the approach in an industrial production.The Red Cross needs to review the cooperation between Zäntrumprojektet and the second-hand store Kupan. Both groups have great potential and opportunities exist for successful co-operation between them. / Program: Textilingenjörsutbildningen
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Finding Torsion-free Groups Which Do Not Have the Unique Product PropertySoelberg, Lindsay Jennae 01 July 2018 (has links)
This thesis discusses the Kaplansky zero divisor conjecture. The conjecture states that a group ring of a torsion-free group over a field has no nonzero zero divisors. There are situations for which this conjecture is known to hold, such as linearly orderable groups, unique product groups, solvable groups, and elementary amenable groups. This paper considers the possibility that the conjecture is false and there is some counterexample in existence. The approach to searching for such a counterexample discussed here is to first find a torsion-free group that has subsets A and B such that AB has no unique product. We do this by exhaustively searching for the subsets A and B with fixed small sizes. When |A| = 1 or 2 and |B| is arbitrary we know that AB contains a unique product, but when |A| is larger, not much was previously known. After an example is found we then verify that the sets are contained in a torsion-free group and further investigate whether the group ring yields a nonzero zero divisor. Together with Dr. Pace P. Nielsen, assistant math professor of Brigham Young University, we created code that was implemented in Magma, a computational algebra system, for the purpose of considering each size of A and B and running through each case. Along the way we check for the possibility of torsion elements and for other conditions that lead to contradictions, such as a decrease in the size of A or B. Our results are the following: If A and B are sets of the sizes below contained in a torsion-free group, then they must contain a unique product. |A| = 3 and |B| ≤ 16; |A| = 4 and |B| ≤ 12; |A| = 5 and |B| ≤ 9; |A| = 6 and |B| ≤ 7. We have continued to run cases of larger size and hope to increase the size of B for each size of A. Additionally, we found a torsion-free group containing sets A and B, both of size 8, where AB has no unique product. Though this group does not yield a counterexample for the Kaplansky zero divisor conjecture, it is the smallest explicit example of a non-uniqueproduct group in terms of the size of A and B.
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Generalized factorization in commutative rings with zero-divisorsMooney, Christopher Park 01 July 2013 (has links)
The study of factorization in integral domains has a long history. Unique factorization domains, like the integers, have been studied extensively for many years. More recently, mathematicians have turned their attention to generalizations of this such as Dedekind domains or other domains which have weaker factorization properties. Many authors have sought to generalize the notion of factorization in domains. One particular method which has encapsulated many of the generalizations into a single study is that of tau-factorization, studied extensively by A. Frazier and D.D. Anderson.
Another generalization comes in the form of studying factorization in rings with zero-divisors. Factorization gets quite complicated when zero-divisors are present due to the existence of several types of associate relations as well as several choices about what to consider the irreducible elements.
In this thesis, we investigate several methods for extending the theory of tau-factorization into rings with zero-divisors. We investigate several methods including: 1) the approach used by A.G. Agargun and D.D. Anderson, S. Chun and S. Valdes-Leon in several papers; 2) the method of U-factorization developed by C.R. Fletcher and extended by M. Axtell, J. Stickles, and N. Baeth and 3) the method of regular factorizations and 4) the method of complete factorizations.
This thesis synthesizes the work done in the theory of generalized factorization and factorization in rings with zero-divisors. Along the way, we encounter several nice applications of the factorization theory. Using tau_z-factorizations, we discover a nice relationship with zero-divisor graphs studied by I. Beck as well as D.D. Anderson, D.F. Anderson, A. Frazier, A. Lauve, and P. Livingston. Using tau-U-factorization, we are able to answer many questions that arise when discussing direct products of rings.
There are several benefits to the regular factorization factorization approach due to the various notions of associate and irreducible coinciding on regular elements greatly simplifying many of the finite factorization property relationships. Complete factorization is a very natural and effective approach taken to studying factorization in rings with zero-divisors. There are several nice results stemming from extending tau-factorization in this way. Lastly, an appendix is provided in which several examples of rings satisfying the various finite factorization properties studied throughout the thesis are given.
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