Dissertations / Theses: 'Knowledge partitioning and distribution'

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De, Oliveira Joffrey. "Gestion de graphes de connaissances dans l'informatique en périphérie : gestion de flux, autonomie et adaptabilité." Electronic Thesis or Diss., Université Gustave Eiffel, 2023. http://www.theses.fr/2023UEFL2069.

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Les travaux de recherche menés dans le cadre de cette thèse de doctorat se situent à l'interface du Web sémantique, des bases de données et de l'informatique en périphérie (généralement dénotée Edge computing). En effet, notre objectif est de concevoir, développer et évaluer un système de gestion de bases de données (SGBD) basé sur le modèle de données Resource Description Framework (RDF) du W3C, qui doit être adapté aux terminaux que l'on trouve dans l'informatique périphérique. Les applications possibles d'un tel système sont nombreuses et couvrent un large éventail de secteurs tels que l'industrie, la finance et la médecine, pour n'en citer que quelques-uns. Pour preuve, le sujet de cette thèse a été défini avec l'équipe du laboratoire d'informatique et d'intelligence artificielle (CSAI) du ENGIE Lab CRIGEN. Ce dernier est le centre de recherche et de développement d'ENGIE dédié aux gaz verts (hydrogène, biogaz et gaz liquéfiés), aux nouveaux usages de l'énergie dans les villes et les bâtiments, à l'industrie et aux technologies émergentes (numérique et intelligence artificielle, drones et robots, nanotechnologies et capteurs). Le CSAI a financé cette thèse dans le cadre d'une collaboration de type CIFRE. Les fonctionnalités d'un système satisfaisant ces caractéristiques doivent permettre de détecter de manière pertinente et efficace des anomalies et des situations exceptionnelles depuis des mesures provenant de capteurs et/ou actuateurs. Dans un contexte industriel, cela peut correspondre à la détection de mesures, par exemple de pression ou de débit sur un réseau de distribution de gaz, trop élevées qui pourraient potentiellement compromettre des infrastructures ou même la sécurité des individus. Le mode opératoire de cette détection doit se faire au travers d'une approche conviviale pour permettre au plus grand nombre d'utilisateurs, y compris les non-programmeurs, de décrire les situations à risque. L'approche doit donc être déclarative, et non procédurale, et doit donc s'appuyer sur un langage de requêtes, par exemple SPARQL. Nous estimons que l'apport des technologies du Web sémantique peut être prépondérant dans un tel contexte. En effet, la capacité à inférer des conséquences implicites depuis des données et connaissances explicites constitue un moyen de créer de nouveaux services qui se distinguent par leur aptitude à s'ajuster aux circonstances rencontrées et à prendre des décisions de manière autonome. Cela peut se traduire par la génération de nouvelles requêtes dans certaines situations alarmantes ou bien en définissant un sous-graphe minimal de connaissances dont une instance de notre SGBD a besoin pour répondre à l'ensemble de ses requêtes. La conception d'un tel SGBD doit également prendre en compte les contraintes inhérentes de l'informatique en périphérie, c'est-à-dire les limites en terme de capacité de calcul, de stockage, de bande passante et parfois énergétique (lorsque le terminal est alimenté par un panneau solaire ou bien une batterie). Il convient donc de faire des choix architecturaux et technologiques satisfaisant ces limitations. Concernant la représentation des données et connaissances, notre choix de conception s'est porté sur les structures de données succinctes (SDS) qui offrent, entre autres, les avantages d'être très compactes et ne nécessitant pas de décompression lors du requêtage. De même, il a été nécessaire d'intégrer la gestion de flux de données au sein de notre SGBD, par exemple avec le support du fenêtrage dans des requêtes SPARQL continues, et des différents services supportés par notre système. Enfin, la détection d'anomalies étant un domaine où les connaissances peuvent évoluer, nous avons intégré le support des modifications au niveau des graphes de connaissances stockés sur les instances des clients de notre SGBD. Ce support se traduit par une extension de certaines structures SDS utilisées dans notre prototype
The research work carried out as part of this PhD thesis lies at the interface between the Semantic Web, databases and edge computing. Indeed, our objective is to design, develop and evaluate a database management system (DBMS) based on the W3C Resource Description Framework (RDF) data model, which must be adapted to the terminals found in Edge computing.The possible applications of such a system are numerous and cover a wide range of sectors such as industry, finance and medicine, to name but a few. As proof of this, the subject of this thesis was defined with the team from the Computer Science and Artificial Intelligence Laboratory (CSAI) at ENGIE Lab CRIGEN. The latter is ENGIE's research and development centre dedicated to green gases (hydrogen, biogas and liquefied gases), new uses of energy in cities and buildings, industry and emerging technologies (digital and artificial intelligence, drones and robots, nanotechnologies and sensors). CSAI financed this thesis as part of a CIFRE-type collaboration.The functionalities of a system satisfying these characteristics must enable anomalies and exceptional situations to be detected in a relevant and effective way from measurements taken by sensors and/or actuators. In an industrial context, this could mean detecting excessively high measurements, for example of pressure or flow rate in a gas distribution network, which could potentially compromise infrastructure or even the safety of individuals. This detection must be carried out using a user-friendly approach to enable as many users as possible, including non-programmers, to describe risk situations. The approach must therefore be declarative, not procedural, and must be based on a query language, such as SPARQL.We believe that Semantic Web technologies can make a major contribution in this context. Indeed, the ability to infer implicit consequences from explicit data and knowledge is a means of creating new services that are distinguished by their ability to adjust to the circumstances encountered and to make autonomous decisions. This can be achieved by generating new queries in certain alarming situations, or by defining a minimal sub-graph of knowledge that an instance of our DBMS needs in order to respond to all of its queries.The design of such a DBMS must also take into account the inherent constraints of Edge computing, i.e. the limits in terms of computing capacity, storage, bandwidth and sometimes energy (when the terminal is powered by a solar panel or a battery). Architectural and technological choices must therefore be made to meet these limitations. With regard to the representation of data and knowledge, our design choice fell on succinct data structures (SDS), which offer, among other advantages, the fact that they are very compact and do not require decompression during querying. Similarly, it was necessary to integrate data flow management within our DBMS, for example with support for windowing in continuous SPARQL queries, and for the various services supported by our system. Finally, as anomaly detection is an area where knowledge can evolve, we have integrated support for modifications to the knowledge graphs stored on the client instances of our DBMS. This support translates into an extension of certain SDS structures used in our prototype

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Yang, Lee-Xieng. "Knowledge partitioning in categorization." University of Western Australia. School of Psychology, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0016.

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Schilhard, Petra. "Distribution of IMUNES System graph partitioning." Saarbrücken VDM Verlag Dr. Müller, 2008. http://d-nb.info/98890893X/04.

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Kaviani, Nima. "Partitioning and distribution of web applications to the hybrid cloud." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50017.

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Hybrid cloud deployment is an effective strategy in deploying software services across public cloud and private infrastructure. It allows deployed software systems to benefit from cost savings and scalability offerings of the cloud while keeping control over privacy- or security-sensitive code and data entities. However, the complexity of determining which code and data entities should reside on-premises, and which can be migrated to the cloud is daunting. Researchers have attempted to address this complexity by using partitioning algorithms to optimize distribution and deployment of code entities across public cloud and private infrastructure. However, we have identified the following shortfalls with the existing research work: Current research does not provide enough flexibility in placement of software function execution and data entities between public/private hosts. In particular it does not allow for replication or optimized separation of code and data entities in relation to one another. Current research on partitioning of software systems does not explicitly consider the dynamics of a hybrid cloud deployment when making decisions about public cloud and private infrastructure. Particularly, current research lacks support for making explicit tradeoff s between monetary cost and improved performance in hybrid cloud software systems. The dynamics of the cloud require partitioning algorithms to be tailored towards features inherent to a hybrid cloud deployment. This includes encoding data dependency models and component dependency models of a software system collectively into one unique mathematical optimization model. There is no existing algorithm that allows for combined code and data dependency requirements to be modelled under one optimization formula. This thesis presents my work on implementing algorithms and tools that address the shortcomings of the previous research as discussed above. These algorithms and tools are put together under a partitioning and distribution framework named Manticore. Manticore has been used to drive partitioning and deployment decisions on several open source software systems. The experiment results show an estimate of up to 54% reduction in monetary costs compared to a premises only deployment and 56% improvement in performance compared to a na ive separation of code entities from data entities in a hybrid cloud deployment.
Science, Faculty of
Computer Science, Department of
Graduate

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MacLeod, Colin D. "Niche partitioning, distribution and competition in North Atlantic beaked whales." Thesis, Aberdeen : University of Aberdeen, 2005. http://www.marineconnection.org/docs/MacLeod_PhD_Thesis.pdf.

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Vicente, de Bobes Joana. "Distribution and partitioning of organic pollutants and effects in coastal birds." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/134824.

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Coastal areas are very susceptible to contamination due to the interaction of marine and anthropogenic processes. Persistent Organic Pollutants (POPs) are organic compounds very resistent to photolysis and chemical and biological degradation. According to its physicochemical characteristics, POPs are worldwide distributed. These contaminants tend to bioaccumulate through the food webs, so that predators are more sensitive to this contamination. Seabirds are highly exposed to organic pollutants due to their feeding habits and its relatively long life. In this thesis, it has been studied the accumulation of various families of organic pollutants in two species of gulls breeding in the Iberian Peninsula, the yellow-legged gull (Larus michahellis) and Audouin's gull (L. audouinii). Yellow-legged gull is a large gull very common in the Iberian Peninsula. It is an omnivorous and opportunistic species. Audouin's gull is endemic of the Mediterranean region. Few years ago it was endangered but the great population growth made to be considered now as "nearly threatened" species. It is a piscivorous species but it is increasingly exploiting more fishery discards and continental preys. In the first study there are determined 6 families of organic pollutants considered by the Stockholm Convention (PCDD/Fs, PBDEs, PCBs, OCs, PFASs and SCCP) in eggs of the two gull species from the Ebro Delta Natural Park. In the following studies, the analyses are based on the study of PFASs in eggs and blood of both gull species and from different colonies of the Iberian Peninsula (Ebro Delta, Medes Islands, Columbretes Islands, Dragonera Island, Grosa Island, Chafarinas Islands, Atlantic Islands of Galicia and Berlengas Islands). From PFASs levels found in the different matrices the effect of these pollutants on physical (biometric parameters of egg, shell thickness and desiccation index) and hormonal level (through the analysis of the steroid hormones: testosterone and 17ß-estradiol) is studied. It is also assessed the accumulation of these pollutants from the diet of both species (analyzing their own food and through the study of the stable isotopes d13C and d15N, as dietary tracers) and it is estimated the PFASs depuration in blood and its transfer from females to eggs. The results indicate that organic pollutants are present in the populations of yellow-legged and Audouin's gull breeding in the Iberian Peninsula colonies, being OCs and PCBs the families of compounds with higher concentrations. Among PFASs, the main compound detected in all samples was PFOS. The transfer of organic contaminants from mother to offspring is demonstrated with the levels found in eggs of both species. Analysis of PFASs in blood of males and females shows that females discharge a fraction of the compounds accumulated to the eggs, thus females had lower blood PFASs levels than males. However, the study of hormonal level allows the comparison between the levels in both gull species and with other studies and to discuss the influence of the different diet. The analysis of PFASs in albumen and egg suggests that these compounds have more affinity for egg-yolk lipids because they are not detected in albumen. The decreasing concentration of PFOS along the egg sequence shows that females PFOS transfer is higher in the first egg but there is also a good correlation between the levels of PFOS among the 3 eggs from the same clutch. The higher concentrations of some PFASs in 3rd eggs (c), comparing with 1st (a) and 2nd (b), and the differences in d13C values between the a-b and b-c eggs are attributed to the "mother effect". This thesis permits increase the knowledge about the accumulation of POPs in yellow-legged and Audouin's gull from the Iberian Peninsula, to evaluate the differences between the two species and determine the geographical distribution of POPs using eggs as a biomarker of environmental contamination and to study the processes of accumulation and transfer of PFAS
Les zones costaneres són unes àrees molt sensibles a la contaminació degut a la interacció entre els processos marins i antropogènics. Els emissaris submarins, les desembocadures dels rius, les activitats portuàries, l’abocament de residus, l’aqüicultura, etc. Són algunes de les activitats que poden produir la contaminació de les zones costaneres. Entre d’altres tipus de contaminants, es troben els contaminants orgànics persistents (COPs), aquells compostos orgànics que, en diferent grau, presenten resistència a la fotòlisis, la degradació química i la biològica. Degut a les seves característiques fisico-químiques, els COPs estan distribuïts per tot el món, podent trobar-se fins i tot en zones prístines molt allunyades de la seva font d’emissió original. Aquests contaminants tendeixen a bioacumular-se al llarg de les cadenes tròfiques, de manera que els grans depredadors són més sensibles a aquesta contaminació. Les aus marines estan molt exposades als contaminants orgànics degut als seus hàbits alimentaris i a la seva esperança de vida relativament llarga. En aquesta tesi s’ha estudiat l’acumulació de vàries famílies de contaminants orgànics en dues espècies de gavina de la Península Ibèrica, el gavià argentat (Larus michahellis) i la gavina corsa (L. audouinii). El gavià argentat és una gavina de grans dimensions molt comuna a la Península Ibèrica. És una espècie omnívora i oportunista. S’alimenta tant de recursos marins, com terrestres, com depredant sobre altres aus i també freqüenta abocadors i descarts pesquers. La gavina corsa és una gavina de dimensions mitjanes, endèmica de la regió mediterrània. Fa uns anys estava en situació de risc però el fort creixement poblacional de les últimes dècades l’ha deixat fora de perill sent considerada actualment a nivell internacional com a “quasi amenaçada”. És una espècie piscívora però cada vegada explota més descarts pesquers. En el primer estudi s’analitzen 6 famílies de contaminants orgànics inclosos o sota consideració pel Conveni d’Estocolm (els PCDD/Fs, PBDEs, PCBs, OCs, PFASs i SCCPs) en els ous de les dues espècies de gavina de les respectives colònies del Parc Natural del Delta de l’Ebre. A partir d’aquí els següents treballs es basen en l’estudi de la família dels PFASs en sang i ous d’ambdues espècies i pertanyents a diferents colònies de la Península Ibèrica (Delta de l’Ebre, Illes Medes, Illes Columbretes, Illa de Sa Dragonera, Illa Grosa, Illes Chafarinas, Illes Atlàntiques de Galicia i Ilhas Berlengas), totes en zones d’alt interès ecològic i sota alguna protecció ambiental (parcs naturals, nacionals, reserves marines, reserva de la biosfera, etc.). A partir dels nivells de PFASs trobats en les diferents matrius (primers ous de la posta, clara i rovell d’ou dels 3 ous de la posta i sang d’exemplars adults) s’estudia l’efecte d’aquests contaminants a nivell físic (paràmetres biomètrics de l’ou, gruix de la closca i índex de dessecació) i hormonal (via l’anàlisi de les hormones esteroidees 17β-estadiol i testosterona). S’estudia també l’acumulació d’aquests contaminants a partir de la dieta (analitzant el seu propi aliment i a partir de l’estudi dels isòtops estables de carboni i nitrogen (δ13C i δ15N), indicadors del règim alimentari) i es fa una estima de la depuració dels PFASs en sang i de la seva transferència de femelles a ous. Els resultats indiquen que els contaminants orgànics són presents en les poblacions de gavià argentat i gavina corsa de la Península Ibèrica, sent els OCs i els PCBs les famílies de compostos amb concentracions més elevades. Entre els PFASs, el compost majoritari és el PFOS. La transferència de contaminants orgànics de mares a cries queda demostrada amb els nivells trobats en els ous d’ambdues espècies. De l’anàlisi de PFASs en sang de mascles i femelles de les dues espècies de gavina s’observa que les femelles descarreguen part dels compostos acumulats als ous presentant així nivells en sang inferior que els mascles. No es troba cap relació entre els nivells de PFASs i els paràmetres biomètrics, com tampoc amb els nivells d’esteroides. Tanmateix, l’estudi de les hormones permet comparar els nivells en ambdues espècies amb altres estudis i discutir la influència de la dieta. L’anàlisi de PFASs en clara i rovell d’ou per separat dels 3 ous de les postes de gavina corsa demostren que aquests compostos tenen més afinitat pels lípids del rovell ja que no es detecten en les clares. La concentració decreixent de PFOS al llarg de la seqüència de posta demostra que les femelles descarreguen la majoria de contaminant en el primer ou però que existeix una bona correlació dels nivells de PFOS entre els 3 ous d’un mateix niu. L’augment de les concentracions d’alguns PFASs en el 3r ou i les diferències en els valors de δ13C entre el 1r-3r i 2n-3r ou s’atribueixen a l’anomenat “efecte mare” (possible ús de reserves endògenes per a la formació de l’últim ou enlloc de l’energia aportada per la dieta prèvia a la posta). Aquesta tesi permet augmentar el coneixement sobre l’acumulació de COPs en el gavià argentat i la gavina corsa de la Península Ibèrica, avaluar les diferències entre ambdues espècies i associar-ho a la seva biologia, determinar la distribució geogràfica de COPs utilitzant els ous com a bioindicador de contaminació ambiental i estudiar els processos d’acumulació i transferència de PFASs.

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Sundström, Maria. "Radiosynthesis of Perfluoroalkyl Substances : Chemical analysis, uptake, distribution, and partitioning studies." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-81061.

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Perfluoroalkyl substances (PFASs) are widely utilized manmade chemicals. Their properties have made them highly appreciated in a variety of industrial and consumer product applications, including fire-fighting foams, hydraulic fluids, as well as in cookware and food contact papers. However, some of the PFASs are highly persistent in the environment and their toxicological profiles are of concern. Voluntary and regulatory efforts have been taken to reduce the environmental levels of PFASs. These actions have resulted in a reduction of PFASs in human milk from Stockholm as presented in this thesis. The radiosyntheses of 35S-PFOS, 35S-PFBS, and 14C-PFOA presented herein were applied for distribution studies in mice but also for solubility and adhesion experiments of common laboratory solvents and buffers. The radiosynthesis employed reactive Grignard reagents, perfluoroalkyliodides, and 35S-sulfur dioxide or 14C-carbon dioxide. The distribution studies were performed with 35S-PFOS on both pregnant mice and their offspring as well as on male mice. The mice were subjected to whole-body autoradiography and the tissues were analyzed by liquid scintillation counting. Liver and lungs were the target organs for 35S-PFOS in the dams. The fetuses and pups had remarkable high levels of 35S-PFOS in their lungs as well as in the brain. The male mice were given a high dose and a more environmental relevant dose of 35S-PFOS. PFOS was transferred from the blood to the tissues as the dose increased. In another study the distribution pattern of the shorter homologue PFBS was compared to PFOS. 35S-PFBS was utilized and demonstrated a 5-40 fold lower tissue levels in comparison to PFOS. The pharmacokinetic parameters determined for PFHxS in mice, rats, and monkeys will provide valuable insight in establishing a proper risk assessment for this compound. The study confirms the common species differences in serum elimination half-life that are associated with PFASs.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 6: Manuscript.

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Burton, Edward D., and n/a. "Distribution and Partitioning of Trace Metals and Tributyltin in Estuarine Sediments." Griffith University. School of Environmental Engineering, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050830.161359.

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An improved understanding of the geochemical partitioning of trace metals and tributyltin (TBT) in sediments is of great importance in risk assessment and remedial investigation. The aim of this thesis was to examine the distribution and partitioning behaviour of trace metals and TBT in benthic, estuarine sediments. This was achieved by a series of field- and laboratory-based studies investigating factors controlling the geochemical behaviour of trace metals and TBT in sediments from south-east Queensland, Australia. The distribution and enrichment of selected trace metals in benthic sediments of the Southport Broadwater (a semi-enclosed coastal body of water adjacent to the Gold Coast city, south-eastern Queensland, Australia) was studied. Sediment contamination for Cd, Cr, Cu, Ni, Pb, Sn and Zn was assessed by (1) comparison with Australian sediment quality guidelines, (2) calculation of the index of geoaccumulation based on regional background values, and (3) geochemical noi-malisation against Al (i.e. the abundance of alumino-silicate clay minerals). Based on this approach, several sites were found to be strongly enriched with Cu, Pb, Sn and Zn, arising from sources related to either urban runoff or vessel maintenance activities. The geochemical partitioning of Cu, Pb and Zn was examined in sediments collected from three of these sites of sediment contamination. Total Cu, Pb and Zn concentrations in coarse-textured (65 to 90 % sand sized particles), sub-oxic sediments (Eh + 120 to +260 mV) ranged from 8.3 to 194 mg/kg for Cu, 16.3 to 74.8 mg/kg for Pb and 30.1 to 220 mg/kg for Zn, and were related to vertical trends in sediment texture. The association of Cu, Pb and Zn with amorphous oxides, crystalline oxides and organic matter was linearly dependent on the abundance of each phase. For retention by amorphous oxide minerals, the trace metal retention ranged from 5.2 to 23.7 mgcjgFe oxide as Fe for Cu, 1 2.8 to 21 .5 mgpb/gFe oxide as Fe for Pb, and 23. I to 85.7 mgm/gFe oxide as Fe for Zn. Corresponding values for association with crystalline oxides were an order of magnitude less than those for amorphous oxides, indicating a weaker affinity of trace metals for crystalline oxides. The relationships describing association with organic matter ranged from 17.6 to 54.0 mgcu/gorg c for Cu, 6.1 to 9.6 mgpb/gorg c for Pb and 6.4 to 16.4 mgzn/gorg c for Zn. The in-situ solid/pore-water partitioning of TBT and the degradation products, dibutyltin (DBT) and monobutyltin (MBT), was determined for an estuarine sediment profile with previously identified elevated Sn concentrations. Total butyltin levels were (depending on depth) 220 to 8750 jig/kg for TBT, 150 to 5450 jig/kg for DBT and 130 to 4250 jig/kg for MBT. Pore-water butyltin concentrations ranged from 0.05 to 2.35 jig/L for TBT, 0.07 to 3.25 jiglL for DBT, and 0.05 to 0.53 J.tgIL for MBT. The organic carbon normalised distribution ratios (Doc) were similar for TBT, DBT and MBT, and were io to 106 L/kg. Values for the Butyltin Degradation Index (BDI) were larger than I at depths greater than 10 cm below the sediment/water-column interface, indicating that substantial TBT degradation has occurred in the sediments. This suggests that natural attenuation may be a viable sediment remediation strategy. Factors controlling the partitioning behaviour of Cu, Pb and Zn in nonsulfidic, estuarine sediments were examined in controlled laboratory-based studies with the use of combined sorption curve - sequential extraction analysis. This allowed determination of sorption parameters for Cu, Pb and Zn partitioning to individual geochemical fractions. Partitioning behaviour in sulfidic sediments was also determined by sequentially extracting Cu, Pb and Zn from synthetic sulfide minerals, and from natural sediment and pure quartz sand after spiking with acid-volatile sulfide (AVS). Trace metal sorption to the 'carbonate' fraction (pH 5, NaOAc extraction) increased with metal loading due to saturation of sorption sites associated with the 'Fe-oxide' (NH2OH.HCI extraction) and 'organic' (H202 extraction) fractions in non-sulfidic sediments. Freundlich isotherm parameters describing sorption to the 'Fe-oxide' and 'organic' fractions were dependent on the sediment Fe-oxide and organic carbon content, respectively. Sequential extraction of Cu from pure CuS, AVS-spiked sediment and AVS-spiked quartz sand showed that AVS-bound Cu was quantitatively recovered in association with the 'organic' fraction. However, some AVS-bound Pb and Zn were recovered by the NH2OH.HCI step (which has been previously interpreted as 'Fe-oxide' bound metals) in the sequential extraction procedure used in this study. This indicates that the sequential extraction of Pb and Zn in sulfidic sediments may lead to AVS-bound metals being mistaken as Fe-oxide bound species. Caution should therefore be exercised when interpreting sequential extraction results for Pb and Zn in anoxic sediments. Tributyltin (TBT) sorption to four natural sediment samples in artificial seawater was also examined under a range of modified pH and salinity conditions in controlled laboratory-based studies. Three of the sediment samples were relatively pristine with regard to TBT contamination, but the fourth was a TBT-contaminated sediment from a commercial marina. Sorption of TBT was described well by linear sorption isotherms, with distribution coefficients ranging from 6.1 to 5210 L/kg depending on pH and salinity. Sediment organic C content and particle size distribution were important determinants of sorption behaviour. The presence of resident TBT in the contaminated marina sediment caused a substantial reduction in TBT sorption due to satuaration of high selectivity sites. Desorption of TBT from the marina sediment was described by relatively large observed distribution coefficients ranging from 5100 to 9400 L/kg, suggesting that aging effects may reduce sorption reversibility. Increased artificial seawater salinity generally reduced TBT sorption at pH 4 and pH 6, but enhanced TBT sorption at pH 8. Regardless of salinity, maximum sorption of TBT was observed at pH 6, which is attributed to an optimal balance between abundance of the cationic TBT species and deprotonated surface ligands. Consideration of aqueous TBT speciation along with octanol-water partitioning behaviour suggest that hydrophobic partitioning of TBTCI to non-polar organic matter was important for pH (up to) 6, whilst partitioning of TBTOH was important at higher pH. The effect of aging on the solid/pore-water partitioning and desorption behaviour of TBT in sediments was examined. Three sediment samples with contrasting physical and chemical properties were spiked with 10 mg/kg TBT and aged under sterile conditions for periods of time ranging from I to 84 days. Aging had a negligible effect in a sandy sample with very low organic carbon content (0.2 % w/w). In contrast, for samples with larger amounts of organic carbon (2.6 and 4.8 % w/w), the effect of aging on the solid/pore-water partitioning behaviour was significant. For these samples, the apparent distribution coefficients (Ks) obtained from sequential two hour desorption experiments exhibited a two-fold increase between spiked sediments subjected to aging for 1 day and 84 days. This study demonstrates that aging effects may be an important aspect of TBT fate in contaminated sediments. Overall, the results described in this thesis demonstrate that environmental factors (i.e. pH, salinity, Eh, aging) and sediment composition (i.e. abundance of fine alumino-silicate minerals, organic matter, Fe-oxides, reactive sulfides) exert substantial effects on trace metal and TBT partitioning. The current reliance on measurement of total trace metal and TBT concentrations in contaminated sediment management may consequently lead to inaccurate estimates of environmental risk and inappropriate remediation measures if other factors regulating contaminant distribution and partitioning are ignored.

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Burton, Edward. "Distribution and Partitioning of Trace Metals and Tributyltin in Estuarine Sediments." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/366133.

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An improved understanding of the geochemical partitioning of trace metals and tributyltin (TBT) in sediments is of great importance in risk assessment and remedial investigation. The aim of this thesis was to examine the distribution and partitioning behaviour of trace metals and TBT in benthic, estuarine sediments. This was achieved by a series of field- and laboratory-based studies investigating factors controlling the geochemical behaviour of trace metals and TBT in sediments from south-east Queensland, Australia. The distribution and enrichment of selected trace metals in benthic sediments of the Southport Broadwater (a semi-enclosed coastal body of water adjacent to the Gold Coast city, south-eastern Queensland, Australia) was studied. Sediment contamination for Cd, Cr, Cu, Ni, Pb, Sn and Zn was assessed by (1) comparison with Australian sediment quality guidelines, (2) calculation of the index of geoaccumulation based on regional background values, and (3) geochemical noi-malisation against Al (i.e. the abundance of alumino-silicate clay minerals). Based on this approach, several sites were found to be strongly enriched with Cu, Pb, Sn and Zn, arising from sources related to either urban runoff or vessel maintenance activities. The geochemical partitioning of Cu, Pb and Zn was examined in sediments collected from three of these sites of sediment contamination. Total Cu, Pb and Zn concentrations in coarse-textured (65 to 90 % sand sized particles), sub-oxic sediments (Eh + 120 to +260 mV) ranged from 8.3 to 194 mg/kg for Cu, 16.3 to 74.8 mg/kg for Pb and 30.1 to 220 mg/kg for Zn, and were related to vertical trends in sediment texture. The association of Cu, Pb and Zn with amorphous oxides, crystalline oxides and organic matter was linearly dependent on the abundance of each phase. For retention by amorphous oxide minerals, the trace metal retention ranged from 5.2 to 23.7 mgcjgFe oxide as Fe for Cu, 1 2.8 to 21 .5 mgpb/gFe oxide as Fe for Pb, and 23. I to 85.7 mgm/gFe oxide as Fe for Zn. Corresponding values for association with crystalline oxides were an order of magnitude less than those for amorphous oxides, indicating a weaker affinity of trace metals for crystalline oxides. The relationships describing association with organic matter ranged from 17.6 to 54.0 mgcu/gorg c for Cu, 6.1 to 9.6 mgpb/gorg c for Pb and 6.4 to 16.4 mgzn/gorg c for Zn. The in-situ solid/pore-water partitioning of TBT and the degradation products, dibutyltin (DBT) and monobutyltin (MBT), was determined for an estuarine sediment profile with previously identified elevated Sn concentrations. Total butyltin levels were (depending on depth) 220 to 8750 jig/kg for TBT, 150 to 5450 jig/kg for DBT and 130 to 4250 jig/kg for MBT. Pore-water butyltin concentrations ranged from 0.05 to 2.35 jig/L for TBT, 0.07 to 3.25 jiglL for DBT, and 0.05 to 0.53 J.tgIL for MBT. The organic carbon normalised distribution ratios (Doc) were similar for TBT, DBT and MBT, and were io to 106 L/kg. Values for the Butyltin Degradation Index (BDI) were larger than I at depths greater than 10 cm below the sediment/water-column interface, indicating that substantial TBT degradation has occurred in the sediments. This suggests that natural attenuation may be a viable sediment remediation strategy. Factors controlling the partitioning behaviour of Cu, Pb and Zn in nonsulfidic, estuarine sediments were examined in controlled laboratory-based studies with the use of combined sorption curve - sequential extraction analysis. This allowed determination of sorption parameters for Cu, Pb and Zn partitioning to individual geochemical fractions. Partitioning behaviour in sulfidic sediments was also determined by sequentially extracting Cu, Pb and Zn from synthetic sulfide minerals, and from natural sediment and pure quartz sand after spiking with acid-volatile sulfide (AVS). Trace metal sorption to the 'carbonate' fraction (pH 5, NaOAc extraction) increased with metal loading due to saturation of sorption sites associated with the 'Fe-oxide' (NH2OH.HCI extraction) and 'organic' (H202 extraction) fractions in non-sulfidic sediments. Freundlich isotherm parameters describing sorption to the 'Fe-oxide' and 'organic' fractions were dependent on the sediment Fe-oxide and organic carbon content, respectively. Sequential extraction of Cu from pure CuS, AVS-spiked sediment and AVS-spiked quartz sand showed that AVS-bound Cu was quantitatively recovered in association with the 'organic' fraction. However, some AVS-bound Pb and Zn were recovered by the NH2OH.HCI step (which has been previously interpreted as 'Fe-oxide' bound metals) in the sequential extraction procedure used in this study. This indicates that the sequential extraction of Pb and Zn in sulfidic sediments may lead to AVS-bound metals being mistaken as Fe-oxide bound species. Caution should therefore be exercised when interpreting sequential extraction results for Pb and Zn in anoxic sediments. Tributyltin (TBT) sorption to four natural sediment samples in artificial seawater was also examined under a range of modified pH and salinity conditions in controlled laboratory-based studies. Three of the sediment samples were relatively pristine with regard to TBT contamination, but the fourth was a TBT-contaminated sediment from a commercial marina. Sorption of TBT was described well by linear sorption isotherms, with distribution coefficients ranging from 6.1 to 5210 L/kg depending on pH and salinity. Sediment organic C content and particle size distribution were important determinants of sorption behaviour. The presence of resident TBT in the contaminated marina sediment caused a substantial reduction in TBT sorption due to satuaration of high selectivity sites. Desorption of TBT from the marina sediment was described by relatively large observed distribution coefficients ranging from 5100 to 9400 L/kg, suggesting that aging effects may reduce sorption reversibility. Increased artificial seawater salinity generally reduced TBT sorption at pH 4 and pH 6, but enhanced TBT sorption at pH 8. Regardless of salinity, maximum sorption of TBT was observed at pH 6, which is attributed to an optimal balance between abundance of the cationic TBT species and deprotonated surface ligands. Consideration of aqueous TBT speciation along with octanol-water partitioning behaviour suggest that hydrophobic partitioning of TBTCI to non-polar organic matter was important for pH (up to) 6, whilst partitioning of TBTOH was important at higher pH. The effect of aging on the solid/pore-water partitioning and desorption behaviour of TBT in sediments was examined. Three sediment samples with contrasting physical and chemical properties were spiked with 10 mg/kg TBT and aged under sterile conditions for periods of time ranging from I to 84 days. Aging had a negligible effect in a sandy sample with very low organic carbon content (0.2 % w/w). In contrast, for samples with larger amounts of organic carbon (2.6 and 4.8 % w/w), the effect of aging on the solid/pore-water partitioning behaviour was significant. For these samples, the apparent distribution coefficients (Ks) obtained from sequential two hour desorption experiments exhibited a two-fold increase between spiked sediments subjected to aging for 1 day and 84 days. This study demonstrates that aging effects may be an important aspect of TBT fate in contaminated sediments. Overall, the results described in this thesis demonstrate that environmental factors (i.e. pH, salinity, Eh, aging) and sediment composition (i.e. abundance of fine alumino-silicate minerals, organic matter, Fe-oxides, reactive sulfides) exert substantial effects on trace metal and TBT partitioning. The current reliance on measurement of total trace metal and TBT concentrations in contaminated sediment management may consequently lead to inaccurate estimates of environmental risk and inappropriate remediation measures if other factors regulating contaminant distribution and partitioning are ignored.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental Engineering
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10

HE, AIJING. "UNSUPERVISED DATA MINING BY RECURSIVE PARTITIONING." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1026406153.

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Bohman, Helena. "Trade, Knowledge and Income Distribution." Doctoral thesis, Jönköping : Jönköping International Business School, Jönköping University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-6687.

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Haimovich, Mordecai, and Thomas L. Magnanti. "Extremum Properties of Hexagonal Partitioning and the Uniform Distribution in Euclidean Location." Massachusetts Institute of Technology, Operations Research Center, 1985. http://hdl.handle.net/1721.1/5369.

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13

Guizol, Léa. "Partitioning semantics for entity resolution and link repairs in bibliographic knowledge bases." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20188/document.

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Nous proposons une approche qualitative pour la résolution d'entités et la réparation de liens dans une base de connaissances bibliographiques. Notre question de recherche est : "Comment détecter et réparer les liens erronés dans une base de connaissances bibliographiques en utilisant des méthodes qualitatives ?". L'approche proposée se décompose en deux grandes parties. La première contribution est une sémantique de partitionnement utilisant des critères symboliques et servant à détecter les liens erronés. La seconde contribution est un algorithme réparant les liens erronés. Nous avons implémenté notre approche et proposé une évaluation qualitative et quantitative pour la sémantique de partitionnement ainsi que prouvé les propriétés des algorithmes utilisés pour la réparation de liens
We propose a qualitative entity resolution approach to repair links in a bibliographicknowledge base. Our research question is: "How to detect and repair erroneouslinks in a bibliographic knowledge base using qualitative methods?" Theproposed approach is decomposed into two major parts. The first contributionconsists in a partitioning semantics using symbolic criteria used in order to detecterroneous links. The second one consists in a repair algorithm restoring link quality.We implemented our approach and proposed qualitative and quantitative evaluationfor the partitioning semantics as well as proving certain properties for the repairalgorithms

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Reid, Miriam Katherine. "An Investigation of the Spatial Distribution and Partitioning of Metals in Estuarine Sediments." Thesis, Queen Mary, University of London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499283.

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Hor, Ching Lai. "Knowledge extraction in transmission and distribution substations." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411335.

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Roth, Andrew E. "Knowledge Sharing Intentions in Wholesale Distribution Organizations." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/1930.

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Millions of American employees are eligible to retire through 2026, which may contribute to lowered organizational performance stemming from the resultant void in knowledge. Increasing knowledge sharing (KS) among organizational members may improve employee efficiency and company performance, and therefore may be of value to wholesale distribution leaders. Although researchers have suggested that sense of self-worth, subjective norms, and attitudes influence employees' inclinations to share knowledge, researchers have not analyzed the relationships between a subset of predictor variables and KS intentions in wholesale distribution organizations. The purpose of this correlational study, grounded in the theory of planned behavior, was to assess the relationship between employees' sense of self-worth, subjective norms, attitudes, and personal intentions to share knowledge with other organizational members. A purposive sample of 82 employees from Northeastern United States wholesale distribution organizations involved in enterprise resource planning implementations completed a survey to examine the propensity for KS. The analysis of the data using multiple linear regression indicated the model was adequate to predict employees' KS intentions. The results of the study further indicated that subjective norms and attitudes were significantly related to personal inclinations to share knowledge. These findings may hold positive social change implications as astute knowledge management can provide for greater employee job security and a more financially secure community. These findings may also be of value to leaders in proactively implementing KS strategies of retiring and other employees in the quest for continued business growth and performance.

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Granchie, Robert C. "Distribution of Partitioning of Lead Related to Soil Characteristics in a Former Gun Range." Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1464795738.

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MacFarlane, Bryan Matthew. "The partitioning and distribution of Zn, Ni, Cr, and Cu in western Lake Erie sediments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0012/MQ52473.pdf.

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Seed, Kevin J. "Chemometric strategies for determining the geochemical association & solid-phase partitioning of selenium : application to soils of the East Midlands." Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270908.

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Collot, Anne-Gaelle. "Co-processing of coal and biomass in a fixed-bed reactor : products distribution and trace elements partitioning." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327030.

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Eberhagen, Niclas. "An investigation of emerging knowledge distribution means and their characterization." Licentiate thesis, Department of Computer and Systems Sciences, Stockholm University, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-8262.

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This work investigates emerging knowledge distribution means through a descriptive study. Despite the amount of attention that processes and structures for knowledge management has received within research during the last decade, little attention has been directed towards the actual means used for the distribution of knowledge by individuals. In this respect it is the aim of the study to contribute with knowledge regarding knowledge distribution means. The study consists of a survey of emerging electronically mediated distribution means followed with a characterization and analysis. For the characterization and analysis a framework for interpretation of the different distribution means was created based on the constructs of organizational learning and the levels of knowledge system interpretation. Within the framework characteristics and concepts were identified and then used for the analysis of the knowledge distribution means. The characterization of the different knowledge distribution means as such may be used as an instrument for evaluation since it generalizable to other means of knowledge distribution. The results of the study show that knowledge distribution is not an isolated event. It takes place in larger context, such as organizational learning, since it touches upon other activities or phenomena such as knowledge acquisition, knowledge interpretation, and organizational memory. The concept of genre of knowledge distribution was found to be a viable concept to base exploration and development of support for knowledge distribution. The investigated distribution means only partly support a model for knowledge representation that captures both the problem-solution as well as an understanding of their relationship. In this respect existing distribution means must be enhanced or new ones developed if we wish to endorse such a representational model.

Licentiate thesis in partial fulfillment of the Licentiate of Philosophy degree in Computer and Systems Sciences, Stockholm University

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Fowler, Michael C. "Intelligent Knowledge Distribution for Multi-Agent Communication, Planning, and Learning." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/97996.

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This dissertation addresses a fundamental question of multi-agent coordination: what infor- mation should be sent to whom and when, with the limited resources available to each agent? Communication requirements for multi-agent systems can be rather high when an accurate picture of the environment and the state of other agents must be maintained. To reduce the impact of multi-agent coordination on networked systems, e.g., power and bandwidth, this dissertation introduces new concepts to enable Intelligent Knowledge Distribution (IKD), including Constrained-action POMDPs (CA-POMDP) and concurrent decentralized (CoDec) POMDPs for an agnostic plug-and-play capability for fully autonomous systems. Each agent runs a CoDec POMDP where all the decision making (motion planning, task allocation, asset monitoring, and communication) are separated into concurrent individual MDPs to reduce the combinatorial explosion of the action and state space while maintaining dependencies between the models. We also introduce the CA-POMDP with action-based constraints on partially observable Markov decision processes, rewards driven by the value of information, and probabilistic constraint satisfaction through discrete optimization and Markov chain Monte Carlo analysis. IKD is adapted real-time through machine learning of the actual environmental impacts on the behavior of the system, including collaboration strategies between autonomous agents, the true value of information between heterogeneous systems, observation probabilities and resource utilization.
Doctor of Philosophy
This dissertation addresses a fundamental question behind when multiple autonomous sys- tems, like drone swarms, in the field need to coordinate and share data: what information should be sent to whom and when, with the limited resources available to each agent? Intelligent Knowledge Distribution is a framework that answers these questions. Communication requirements for multi-agent systems can be rather high when an accurate picture of the environment and the state of other agents must be maintained. To reduce the impact of multi-agent coordination on networked systems, e.g., power and bandwidth, this dissertation introduces new concepts to enable Intelligent Knowledge Distribution (IKD), including Constrained-action POMDPs and concurrent decentralized (CoDec) POMDPs for an agnostic plug-and-play capability for fully autonomous systems. The IKD model was able to demonstrate its validity as a "plug-and-play" library that manages communications between agents that ensures the right information is being transmitted at the right time to the right agent to ensure mission success.

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Frasson, Renato Prata de Moraes. "Understanding the partitioning of rainfall by the maize canopy through computational modelling and physical measurements." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/2702.

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The interception and redirection of rainfall by vegetation has implications for many fields such as remote sensing of soil moisture, satellite observation of rainfall, and the modeling of runoff, climate, and soil erosion. Although the modeling of rainfall partitioning by forests has received attention in the past, partitioning caused by crops has been overlooked. The present work proposes a two front experimental and computational methodology to comprehensively study rainfall interception and partitioning by the maize canopy. In the experimental stage, we deployed two compact weather stations, two optical disdrometers, and five tipping bucket rain gauges. Two of the tipping bucket rain gauges were modified to measure throughfall while two were adapted to measure stemflow. The first optical disdrometer allowed for inspection of the unmodified drop-size and velocity distributions, whereas the second disdrometer measured the corresponding distributions under the canopy. This indicates that the outcome of the interaction between the hydrometeors and the canopy depends on the drop diameter. In the computational stage, we created a model that uses drop-size and velocity distributions as well as a three-dimensional digital canopy to simulate the movement of raindrops on the surfaces of leaves. Our model considers interception, redirection, retention, coalescence, breakup, and re-interception of drops to calculate the stemflow, throughfall, and equivalent height of precipitation stored on plants for a given storm. Moreover, the throughfall results are presented as two-dimensional matrices, where each term corresponds to the accumulated volume of drops that dripped at a given location. This allows insight into the spatial distribution of throughfall beneath the foliage. Finally, we examine the way in which the maize canopy modifies the drop-size distribution by recalculating the drop velocity based on the raindrop's size and detachment height and by storing the counts of drops in diameter-velocity classes that are consistent with the classes used by disdrometers in the experimental study.

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Lohse, Peter A. (Peter Andreas). "Distribution of knowledge production in the chemical sciences in the US." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/65786.

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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 43-44).
A citation analysis was carried out to gain an understanding of the geographical and institutional distribution of highly cited articles in the chemical sciences in the US over the last thirty years. The contribution of US chemistry departments was determined by quantifying the number of highly cited articles published by individual authors or groups of authors from the same department. Articles stemming from collaborative research across schools were not considered. The results show that a dilution in intradepartmental knowledge production has occurred both on a geographical and institutional level. Three chemistry departments have emerged as strong producers of high impact articles over the last thirty years: the University of North Carolina, Texas A&M University and the University of Utah. In terms of aggregate numbers of highly cited articles these three schools are in the top ten of over seventy schools which were evaluated; their chemistry departments are en par in terms of scientific impact with those from Ivy League schools like Stanford University, Harvard University and the California Institute of Technology. While the literature reports increasing concentration for the US research base, the present analysis shows a dilution in chemical knowledge production when collaborative efforts across departments and schools are excluded. This finding suggests that the increase in concentration in the US science base is not a uniform trend when studied on a more granular level.
by Peter A. Lohse.
M.B.A.

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Frisk, Åsa M. "Late Ordovician Faunal Distribution and Ecospace Partitioning in Marine Impact Craters : The Aftermath of the Lockne and Tvären Events." Doctoral thesis, Uppsala universitet, Institutionen för geovetenskaper, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-109605.

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In the Middle to Late Ordovician a boost of marine biodiversity occurred which is regarded as the most rapid diversity in Earth’s history, and termed the Great Ordovician Biodiversification Event. This time is also unique in that at least four marine meteorite craters with a good record of post-impact sediments are preserved in Baltoscandia. Catastrophic impacts can serve as constructive events and produce wide-ranging environments providing new ecological niches for a diverse biota to occupy. Additionally, they generate distinctive patterns of biological destruction and recovery. This, and the study of distribution and ecospace utilisation of Late Ordovician faunas, has been analysed in two almost contemporary (around 455 million years ago) meteorite craters (Lockne and Tvären, Sweden). Within the confined space of the impact craters environments varied from shallow and reef-like to over 200 m in depth and from well oxygenated to hypoxic. These types of environments favored colonization of different individual groups. In Tvären rhynchonelliformean brachiopod assemblages from the shallow crater rim include a range of morphotypes, not established elsewhere in the crater. Within the crater depression rhynchonelliformean brachiopods were not established until the upper third of the remaining crater fill. Colonization of post-impact faunas varies dependent on topography, depth and susbstrate within the impact craters. This is recognised for scolecodonts in Tvären and for gastropod-like mollusks, linguliform and craniiform brachiopods in both of the craters, as they inhabit a wide range of ecospace. A succession of different taxa is observed from the deepest part of each crater and upwards towards inferably more shallow, higher energy, water settings. The development of new community types and narrowly-defined niches in the craters helped further drive both α and β biodiversity during a critical phase of the Great Ordovician Biodiversification Event.

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Pereira-Mendes, Vivaldo M. "Knowledge and increasing returns in recent economic growth." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262718.

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Ghimire, Kabita. "Geographic distribution of malaria in Nepal." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34464.

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Doctor of Philosophy
Department of Geography
Douglas G. Goodin
The malaria burden has decreased in Nepal between 1988 and 2013. However, there are challenges to completely eradicating the disease. Malaria patterns in a few endemic districts have not changed, and higher malaria case rates have been detected within districts which otherwise were categorized as low endemic areas. Underlying biophysical, socioeconomic, and behavioral factors influence malaria transmission and create region-specific patterns. This research employs various concepts, tools, and techniques to understand the geographic distribution of malaria in Nepal. In this research, malaria prevalence patterns were investigated at multiple spatial and temporal scales. The study identifies malaria hot spots, describes their characteristics and examines shifts in malaria hot spots between 1988 and 2013. Within that 26-year time span, 267,121 confirmed malaria cases were recorded. Thirty-nine of 75 districts were identified as malaria hot spots in Nepal. Based on the frequency, persistence and proportion of caseloads each year, the identified hotspots were grouped into five categories; stable, disappearing, emerging, reemerging, and intermittent. The research also investigated the relationship between climatic factors and malaria frequency, and found that temperature and precipitation during the monsoon and non-monsoon seasons played significant roles in determining the absence and presence of malaria and low and high frequency of malaria distribution at the district level. The dissertation also presents the findings of a study that investigated malaria–related knowledge, perceptions and practices among adults in Nepal, specifically knowledge about its signs, symptoms, consequences, and the availability and use of prevention tools. Although a significant portion of respondents had heard of malaria there was wide variation in their knowledge about specific information related to the disease. Locality, age, household size, education, and income were significantly associated with malaria–related knowledge.

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George, Chadrick Hendrik. "Knowledge management infrastructure and knowledge sharing: The case of a large fast moving consumer goods distribution centre in the Western Cape." Thesis, University of the Western Cape, 2014. http://hdl.handle.net/11394/3943.

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Magister Commercii - MCom
The aim of this study is to understand how knowledge is created, shared and used within the fast moving consumer goods distribution centre in the Western Cape (WC). It also aims to understand knowledge sharing between individuals in the organisation. A literature review was conducted, in order to answer the research questions- this covered the background of knowledge management (KM) and KS and its current status with particular reference to SA’s private sector. The study found that technological KM infrastructure, cultural KM infrastructure and organisational KM infrastructure are important enablers of KS. A conceptual model was developed around these concepts. In order to answer the research questions, the study identified a FMCG DC in the WC, where KS is practiced

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Millsaps, Gayle Maree. "Interrelationships between teachers' content knowledge of rational number, their instructional practice, and students' emergent conceptual knowledge of rational number." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1124225634.

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He, Yuqing. "Distribution and Evolution of Actors’ Roles in Knowledge Transfer in Innovation Networks." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39837.

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Collaborative innovation is an important mechanism for firms to exchange and acquire external knowledge. Through collaboration, innovators convene and form networks that, in return, help overcome the boundaries of knowledge transfer. To have a better understanding of actors’ collaborating behaviours in innovation networks, we identify three pairs of roles: 1) do actors make connections or bonds with their partners? 2) do actors exchange their knowledge with internal or external partners? 3) do actors absorb or distribute knowledge? We examine the distribution and evolution of actors’ roles from these three perspectives by using social network analysis. In this thesis, we use thousands of patent data from the United States Patent and Trademark Office, to investigate the actors’ behaviours in the chemical industries of two Canadian regions, i.e. Montreal and Windsor-Sarnia. Based on the results of our analysis, Montreal, acting as a public-dominated region, shows a more complex distribution of roles, while Windsor-Sarnia with a private orientation indicates a simplex pattern. From the evolution perspective, the network of Montreal is more stable and diversified, with key actors being active in the local network for more extended periods. Unlike Montreal, Windsor-Sarnia faces a higher level of mobility and globalization.

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Chaulk, Amanda Holly. "Distribution and partitioning of mercury in the Arctic cryosphere: transport across snow-sea ice-water interfaces in the western Arctic Ocean." ACS Publications, 2011. http://hdl.handle.net/1993/4895.

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The high toxicity and ability to be transported over long distances and biomagnify up food chains have earned Mercury (Hg) recognition as a contaminant of global concern. The Arctic region is particularly vulnerable to Hg with high levels of Hg being detected in marine mammals. The importance of the cryosphere, especially sea ice, has often been neglected in considerations of the extent to which atmospherically derived Hg impinges on the underlying marine system. This thesis reports the first systematic study of Hg transport in the Arctic cryosphere (sea ice, brine, snow, and melt ponds) conducted in the Amundsen Gulf from February to June 2008. Hg concentrations in bulk first-year sea ice were generally low (0.5 – 4 ng L-1), with the highest concentration in the surface granular ice layer. The highest concentrations of Hg were found in sea ice brine (up to 70 ng L-1). Atmospheric mercury depletion events (AMDEs) appear not to be an important factor in determining Hg in sea ice, with the exception of in frost flowers. Evidence of Hg accumulation during melt – refreezing cycles is seen in multi-year ice. Significant impact of AMDEs is observed on Hg concentrations in snow. Rates of deposition of atmospheric Hg ranged from 200 – 784 ng m-2 into the top 1 cm of snow. Although photo reduction and reemission to the atmosphere does occur, a considerable fraction of deposited Hg is retained in the snowpack due to subsequent burial. At one station it is estimated that less than 50% of the deposited Hg is re-emitted to the atmosphere. It is suggested that in the Beaufort Sea, where AMDEs occur frequently due to dynamic nature of the sea ice environment, a larger than suspected portion of atmospherically deposited Hg can be retained in the snowpack and enter the underlying marine system upon melt later in the season.

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Loh, Ai Ning. "Distribution, Partitioning and Fluxes of Dissolved and Particulate Organic Carbon, Nitrogen and Phosphorus in the Eastern North Pacific and Southern Oceans." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539617737.

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33

Kosov, Sergey. "Intelligent pressure control and diagnosis of water distribution networks." Thesis, De Montfort University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391542.

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Little, Daniel R. "Sensitivity to correlation in probabilistic environments." University of Western Australia. School of Psychology, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0013.

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Natural categories seem to be comprised of clustered stimuli that contain a myriad of correlated features; birds, for example, tend to fly, have wings, lay eggs, and make nests. Nonetheless, the evidence that people use these correlations during intentional category learning is overwhelmingly negative (Murphy, 2002). People do, however, show evidence of correlational sensitivity during other types of category learning tasks (e.g., feature prediction). The usual explanation is that intentional category learning tasks promote rule use, which discards the correlated feature information; whereas, other types of category learning tasks promote exemplar storage, which preserves correlated feature information. However, all of the intentional category learning tasks employed to examine correlational sensitivity to date have only used deterministic mappings of stimuli to categories (i.e., each stimulus belongs to only one category). The current thesis is concerned primarily with the effects introducing the probabilistic assignment of stimuli to categories on the acquisition of different types of correlational knowledge. If correlational knowledge depends on whether or not people selectively attend to the correlation then probabilistic reinforcement, which is predicted to increase attention shifting (Kruschke & Johansen, 1999), should lead to increased correlational sensitivity. The first paper of this thesis confirms that selective attention provides a way to explain the presence or absence of correlational knowledge in different tasks. However, selective attention models have been unable to account for tasks in which people use the correlation between a non-relevant cue and regions of the category space to switch between the application of multiple rules. This phenomenon, known as knowledge partitioning, is explored in the second paper of this thesis. This thesis also extends the empirical implications of the first two papers to existing research (see included paper 3) and also provides recommendations of how utilize this conceptualization of knowledge for practitioners in the applied setting (see included paper 4). Finally, in addition to increasing attention shifting, probabilistic feedback is also assumed to result in an attenuation of learning over time (Kruschke & Johansen, 1999); the fifth paper in this thesis provides empirical confirmation that people attenuate learning in response to unavoidable error.

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Fall, Jakob, and Rebecca Klinc. "Efficient information and knowledge distribution in high-tech production units utilizing graphical user interfaces." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188813.

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This study aims to examine potential efficiency gains within a manufacturing unit by implementing processes for knowledge and information distribution. A specialized software tool, implementing processes for knowledge and information distribution, was developed and then examined to see if any efficiency gains could be accomplished. The scientific questions to be addressed were: Will well-defined strategies and processes for information and knowledge management lead to higher efficiency within a manufacturing unit? Is a specialized software a useful tool and how should it be designed to facilitate efficient information and knowledge management? With the help of information management theories, interviews and a field study five main problem areas were found. To counter the problem areas and approach the technical aspect of this study human-computer interactions theories were used to develop three prototypes in an iterative process. The third and final prototype was evaluated by using user testing and interview questions. We found that well-defined strategies and processes for information and knowledge management lead to higher efficiency within a manufacturing unit. By using the specialized software tool it will be easier to facilitate efficient information and knowledge management and that general rules on how to create such a software exists. Due to the result and reactions from the employees our recommendations is for FLIR Systems AB to conduct an implementation study using our software as the frontend.
Denna studies mål är att undersöka eventuella effektivitetsvinster inom en tillverkningsenhet genom att implementera processer för kunskaps- och informationsspridning. Ett specialiserat verktyg, som implementera de processer för kunskap och informationsspridning, har utvecklats och sedan granskas för att se om några effektivitetsvinster kan åstadkommas. De vetenskapliga frågor som skall besvaras är: Kommer väldefinierade strategier och processer för informations- och kunskapsspridning att leda till ökad effektivitet inom en tillverkningsenhet? Är en specialiserad mjukvara ett användbart verktyg och hur ska den designas för att uppmuntra effektiv informations- och kunskapshantering? Fem problemområden identifierade med hjälp av teorier om informationshantering, intervjuer och en fältstudie. För att förbättra de problemområden och närma den tekniska aspekten av denna studie användes människa-datorinteraktionsteorier för att utveckla tre prototyper i en iterativ process. Den tredje och sista prototypen utvärderades med hjälp av användartester och intervjufrågor. Vi fann att väldefinierade strategier och processer för information och kunskapshantering leder till högre effektivitet inom en tillverkningsenhet. Genom att använda ett specialiserat verktyg underlättar det för en effektiv informations- och kunskapshantering. Vi fann även att allmänna regler för hur man designar en sådan mjukvara existerar. Utifrån resultatet och reaktionerna från de anställda är våra rekommendationer för FLIR Systems AB att genomföra en implementationsstudie med hjälp av vår programvara som interface.

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Ho, Hillbun, and Hillbun Ho. "Knowledge Sharing Between Competing Suppliers in the Customer's Supply Chain Network." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/196073.

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Drawing on the marketing, strategic management, and supply management literature, this dissertation develops and empirically tests a theoretical model that delineates knowledge sharing and collaboration between competing suppliers in serving a buying organization. Data were collected through the means of a conjoint-decision study and a survey of suppliers in the optics and the automotive industries. One hundred and forty-six executive MBA students participated in the conjoint-decision study, and one hundred and ten companies participated in the survey. Statistical analysis results from both studies show strong empirical support to the theoretical model. This dissertation advances our understanding of the relative impacts of different factors in promoting or constraining knowledge sharing between competing suppliers when they collaborate with each other to create superior value for the customer. This dissertation demonstrates that a focal supplier's transfer of knowledge to its counterpart hinges not solely on the characteristics of the collaboration. More importantly, knowledge sharing between two competing suppliers is related to different facets of the customer's relationship with the focal supplier. In conclusion, this dissertation provides substantial insights into the role and influences of the customer on competing suppliers' knowledge sharing and collaboration, as well as the value of knowledge sharing to the strategic outcomes of the inter-supplier collaboration.

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Sewell, David K. "Restructuring partitioned knowledge : evidence of strategy retention in category learning." University of Western Australia. Faculty of Life and Physical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0008.

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A recurring theme in the cognitive development literature is the notion that people restructure their task knowledge as they develop increasingly sophisticated strategies. A large body of empirical literature spanning several domains suggests that in some cases, the process of knowledge restructuring is best characterized by a process of sequentially replacing old strategies with newer ones. In other cases, restructuring appears to be better characterized as a process involving changes in the way partial knowledge elements are selectively applied to a task. Critically, the former, but not the latter position, suggests that it may be quite difficult for people to revert to using an old strategy after restructuring has already occurred. The three experiments reported herein suggest that knowledge restructuring observed in experimental settings is aptly characterized by a process of strategy retention. Specifically, people are shown to readily revert to using an old categorization strategy even after demonstrably having restructured their knowledge, suggesting that knowledge is best conceptualized as having a heterogeneous structure. Formal modeling further supports this interpretation of the empirical results, and highlights the important role of selective attention in determining the manifest response strategy. The implications of these findings are discussed in terms of an overarching mixture-of-experts framework of knowledge representation.

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Eisses, Rebecca D. "Comparative analysis of modernization of crop production and knowledge distribution in the West Visayas, Philippines." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ49346.pdf.

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Mohamed, Shamboul Adlan. "Automated document distribution with signature release authority using AI-based workstations and knowledge base servers." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184596.

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Document distribution in a large corporation requires a set of routing procedures for each type of document. Documents may include memorandums, payroll reports, technical reports, external correspondence, and internal mail. Some of these documents may require managerial review and signature release authority to leave the organization. The document must be routed through the different levels of the organization according to the document procedures. The availability of the signers and reviewers becomes a delay factor in the routing of the document. This dissertation describes an approach to a solution to this problem using artificial intelligence and expert system concepts coupled with distributed computer networking to distribute the documents. A prototype system has been demonstrated. A document is originated as an "electronic file" on a user workstation (WS), called the Writer. The document is processed by an inference engine in the WS which also appends the list of Signers and Reviewers. The document is then sent to a Knowledge Base Server (KBS) which adds additional information regarding the distribution of the document. Each document contains headers for the communications network in the organization, distribution control header, and the document text body. The KBS stores the document according to the user profiles in the organizations. Activity of reviewing and signing the documents is originated at the user WS. The document is retrieved from the KBS, reviewed by the user, signed and returned to the KBS for intermediate storage. When the KBS has determined that the document has all the required signatures (Signwords), the document is sent to the final destination. The automated document distribution system summarized above has been demonstrated using a C language implementation on PC workstations and a UNIX-based KBS. The PCs are AT&T 6300 systems and the KBS is an AT&T 3B2/310 system. The communications network is a Sytek LocalNet 20 broadband local area network. Knowledge about document processing and distribution is distributed between local workstations' knowledge bases and the KBS. The second phase of the project involves implementing the system using AI and expert systems tools in the PCs and KBS.

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Mastio, Matthieu. "Modèles de distribution pour la simulation de trafic multi-agent." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1147/document.

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L'analyse et la prévision du comportement des réseaux de transport sont aujourd'hui des éléments cruciaux pour la mise en place de politiques de gestion territoriale. La simulation informatique du trafic routier est un outil puissant permettant de tester des stratégies de gestion avant de les déployer dans un contexte opérationnel. La simulation du trafic à l'échelle d'un ville requiert cependant une puissance de calcul très importante, dépassant les capacité d'un seul ordinateur.Dans cette thèse, nous étudions des méthodes permettant d'effectuer des simulations de trafic multi-agent à large échelle. Nous proposons des solutions permettant de distribuer l'exécution de telles simulations sur un grand nombre de coe urs de calcul. L'une d'elle distribue directement les agents sur les coeurs disponibles, tandis que la seconde découpe l'environnement sur lequel les agents évoluent. Les méthodes de partitionnement de graphes sont étudiées à cet effet, et nous proposons une procédure de partitionnement spécialement adaptée à la simulation de trafic multi-agent. Un algorithme d'équilibrage de charge dynamique est également développé, afin d'optimiser les performances de la distribution de la simulation microscopique.Les solutions proposées ont été éprouvées sur un réseau réel représentant la zone de Paris-Saclay.Ces solutions sont génériques et peuvent être appliquées sur la plupart des simulateurs existants.Les résultats montrent que la distribution des agents améliore grandement les performances de la simulation macroscopique, tandis que le découpage de l'environnement est plus adapté à la simulation microscopique. Notre algorithme d'équilibrage de charge améliore en outre significativement l'efficacité de la distribution de l'environnement
Nowadays, analysis and prediction of transport network behavior are crucial elements for the implementation of territorial management policies. Computer simulation of road traffic is a powerful tool for testing management strategies before deploying them in an operational context. Simulation of city-wide traffic requires significant computing power exceeding the capacity of a single computer.This thesis studies the methods to perform large-scale multi-agent traffic simulations. We propose solutions allowing the distribution of such simulations on a large amount of computing cores.One of them distributes the agents directly on the available cores, while the second splits the environment on which the agents evolve. Graph partitioning methods are studied for this purpose, and we propose a partitioning procedure specially adapted to the multi-agent traffic simulation. A dynamic load balancing algorithm is also developed to optimize the performance of the microscopic simulation distribution.The proposed solutions have been tested on a real network representing the Paris-Saclay area.These solutions are generic and can be applied to most existing simulators.The results show that the distribution of the agents greatly improves the performance of the macroscopic simulation, whereas the environment distribution is more suited to microscopic simulation. Our load balancing algorithm also significantly improves the efficiency of the environment based distribution

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Burga, Mario, Jesus Jimenez, Fernando Sotelo, and Carlos Raymundo. "Operational performance measurement model based on knowledge management to reduce orders returned for a distribution company." Latin American and Caribbean Consortium of Engineering Institutions, 2019. http://hdl.handle.net/10757/656261.

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Small and medium-sized enterprises (SMEs) in Peru present problems such as access to the national market due to limited capital or access to technology compared to large companies. However, they also lack an adequate definition and conceptualization of their processes, as well as a low level of business information transfer, which causes an absence in the measurement, control of processes and low operational performance. Given this situation, we propose the application and implementation of knowledge management tools in a company dedicated to the marketing and distribution of school supplies, which represents an SME in Peru. The tools used as the map of processes and flowcharts of the different processes were used to make the participants of the processes known. Through the realization of training, performance evaluations and internal audit, the learning of the operator is analyzed. As a result, there was a 57.63% decrease in errors in armed orders during picking, as well as a decrease of 7.98% and 8.59% of times in the execution of the processes under study for small orders and larger orders, respectively. Similarly, 96.56% of dispatches generated correctly were obtained.

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Gomes, Tatiana Mateus. "Aplicação de métricas de confiabilidade para avaliação da setorização de sistemas de abastecimento de água." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-18032019-164514/.

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Os avanços observados em Sistemas de Distribuição de Água vêm surgindo da necessidade de aumentar a eficiência, a qualidade e segurança do abastecimento de água aos consumidores. Dois desses avanços recentes que podem ser citados são a setorização e a quantificação da confiabilidade. O processo de setorização de um sistema de distribuição de água favorece a sua gestão, uma vez que possibilita maior controle da vazão distribuída e dos limites de fornecimento do serviço, entretanto pode implicar em restrições no abastecimento durante eventos de falhas ou emergências, sendo necessária a avaliação da confiabilidade. Diversos pesquisadores têm buscado uma metodologia coerente e adequada para quantificar a confiabilidade em sistemas de distribuição de água, muitos deles desenvolvendo métricas alternativas que visam simplificar esta definição. O presente trabalho visou investigar métricas alternativas de confiabilidade, propostas na literatura especializada, aplicando-as a estudos de caso para a rede original e após a setorização. Os resultados sugerem a viabilidade de utilização das métricas de confiabilidade como forma de avaliar diferentes níveis de setorização, no que diz respeito à vulnerabilidade do sistema.
Improvements upon Water Distribution Systems have been made under the urge of increasing efficiency, quality and security of water supply to its customers. A couple of recent breakthroughs on Water Distribution Network are partitioning and reliability. Water network partitioning enhances operational management, once it enables higher control of supplied flow and awareness of boundaries regarding each partition. Nevertheless, it can lead to supply restrictions under emergency and failure events, what may require reliability assessment. Several researchers have pursued consistent approach to quantify reliability of Water Distribution Network, many of them proposed surrogate measures which focused on simplifying its measurement. The aim of this work is to look into surrogate reliability measures proposed in the literature and applying them on case studies for its original layout and after proposed partitioning. The results implies the usage feasibility for the reliability measures as a way of evaluating different stages of partitioning, regarding system\'s vulnerability.

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Saqib, Naeem. "Distribution and chemical association of trace elements in incinerator residues and mining waste from a leaching perspective." Doctoral thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-48933.

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Incineration is a mainstream strategy for solid waste management in Sweden and all over the world. Improved knowledge and understanding about the distribution of trace elements (in ashes) during incineration, and how trace element partitioning respond to the changes in waste composition, are important in terms of combustion process optimization and plant efficiency. Moreover, determination of chemical association of trace elements in ashes are vital for avoiding environmental concerns and to promote possible reuse. In this study, partitioning of trace elements in ashes during incineration as function of input waste fuel and incineration technology was investigated. Further, chemical association of trace elements in resulting ashes was studied. An evaluation was also performed about feasibility of metal extraction from sulfidic mining waste and flotation tailings. Moreover, green liquor dreg (GLD) was tested with respect to stabilization of metals within the sulfidic mining waste. Findings showed that the total input of trace elements and chlorine affects the partitioning and increasing chlorine in the input waste caused increase in transfer of trace elements to fly ash especially for lead and zinc. Vaporization, condensation on fly ash particles and adsorption mechanisms play an important role for metal distribution. Firing mixed waste, especially biofuel mix, in grate or fluidized (CFB) boilers caused increased transfer into fly ash for almost all trace elements particularly lead and zinc. Possible reasons might be either an increased input concentration of respective element in the waste fuel, or a change in volatilization behavior due to the addition of certain waste fractions. Chemical association study for fly ashes indicated that overall, Cd, Pb, Zn, Cu and Sb are presenting major risk in most of the fly ashes, while in bottom ashes, most of elements are associated with stable fraction. Further, fuel type affects the association of elements in ashes. Chemical leaching of mining waste materials showed that sulfuric acid (under different conditions) is the best reagent to recover zinc and copper from sulfidic mining waste and also copper from flotation tailings. GLD indicates potential for metal stabilization in mining waste by reducing the metal mobility. Extraction methods could be applied to treat mining waste in order to meet the regulatory level at a specific mining site.Similarly stabilization/solidification methods might be applied after leaching for recovery of metals.

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Lüthje, Christian, Christopher Lettl, and Cornelius Herstatt. "Knowledge distribution among market experts: A closer look into the efficiency of information gathering for innovation projects." Inderscience, 2003. http://dx.doi.org/10.1504/IJTM.2003.003423.

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Information gathering from sources outside the company plays a critical role in most innovation projects. Particularly, it seems promising to approach external market experts to develop an indepth understanding of current use problems, changing customer needs and trends for new product solutions. When planning expert interviews, firms are confronted with the question whether knowledge is distributed rather homogeneously or heterogeneously ("scattered") among a pool of experts. This issue strongly determines how many experts need to be interviewed in order to develop a comprehensive understanding of a given search field for innovation. In the present paper we analyse expert interviews that were conducted in the context of an innovation project in the field of surgical hygiene products. We find high heterogeneity of expert knowledge: Market experts in our sample vary in terms of market information they provide for the particular product field. We argue that this finding is in alignment with the concept of "bounded rationality" and the theory of "contextual development of knowledge". Our findings have implications for the management of external information gathering and the identification of market experts.(author's abstract)

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Graves, Kathleen. "Understanding language classrooms as social practices : competence, roles and distribution of knowledge in an adult ESL class." Thesis, Lancaster University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420565.

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McDonnell, Janet Theresa. "Supporting engineering design using knowledge based systems technology with a case study in electricity distribution network design." Thesis, Brunel University, 1994. http://bura.brunel.ac.uk/handle/2438/5443.

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This thesis explores the architectural requirements of engineering design support systems based on knowledge based systems technology. The exploration is based on an understanding of the nature of designing as a professional activity and on the extent to which designers' competence can be modelled. Attention is focused on certain salient aspects of designers' competent behaviour. The theoretical study leads to the specification of requirements to be satisfied by a knowledge based system which will support designers in their professional setting and to the proposal of some knowledge based system components which will meet the requirements identified. The theoretical aspect of the thesis is complemented by a case study based on a designer of high voltage electricity distribution networks. The case study illustrates the theoretical component of the thesis and the methodological basis for the work. The practical realizability of the components of the knowledge based systems architecture proposed are demonstrated using the results of the analysis of the knowledge elicited in the case study without prejudicing the general applicability of the ideas. An object-oriented knowledge engineering software development environment is used to demonstrate how some components of the design situation represented can be implemented.

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Meiring, Linda. "A distribution model for the assessment of database systems knowledge and skills among second-year university students." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/44.

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Crow, Frederick W. IV. "The False Appeal of Middle Knowledge: A Critique of Alvin Plantinga’s Commitment to Counterfactuals of Freedom." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou159183292305403.

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Yu, Tiecheng. "Transfer and integration of human resources management knowledge within dynamic supply chains : cases from the automotive aftermarket distribution system in China." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/transfer-and-integration-of-human-resources-management-knowledge-within-dynamic-supply-chains-cases-from-the-automotive-aftermarket-distribution-system-in-china(ddc4b5b2-25a8-47e3-aba8-d96d7a9e256f).html.

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This thesis explores the scope for the transfer and integration of human resources management (HRM) knowledge to provide the basis for the development of more productive and efficient supply chains, in the specific case of the aftermarket distribution channels of multinational companies in the automotive industry in China. Most studies of human resources management, supply chain management, and knowledge transfer have focused on internal transfer within multinational companies and there has been more limited research on the transfer of such knowledge across organisations in the supply chain, particularly in relation to distribution channels. Thus the starting point for the research was to understand the preconditions, mechanisms and effects on the distribution supply chain of the transfer and integration of HRM knowledge. To explore these issues the thesis compares and contrasts a poorly performing supply chain (that is Company J's supply chain) with two more successful supply chains in the automotive aftersales market (that is those of Company M and Company S). The aim was to identify whether the poorly performing supply chain could learn from the other two cases through a detailed exploration of the motivators and mediators that facilitate or hinder processes of HRM transfer and integration, and the outcomes of these processes on the performance of the supply chains and the manufacturers and distributors within the supply chains. A qualitative research approach was utilised. Data was gathered through one-on-one, semi-structured interviews with senior-level management, mid-level management, and frontline staff from the manufacturers and wholesale distributors in the three automotive aftermarket distribution channels and analysed using computer-assisted coding software, NVivo. In line with the extant literature, the thesis findings support the proposition that a relational supply chain network based on trust facilitates HRM knowledge transfer and integration, and provides a basis for competitive advantage in the supply chain. At the same time the findings suggest some important extensions to current knowledge and understanding of the processes and impact of HRM knowledge transfer. Firstly the research found that consideration should be given to recategorising the classic division between tacit and explicit knowledge with respect to HRM into fundamental and differential categories, in order to more clearly differentiate the type of strategic HRM knowledge transfer that could provide the basis for competitive advantage. Likewise the study found that it is not the mechanism of transfer- whether through systems or by inter-person channels- that should be the criteria to categorise knowledge, as a blended approach involving both types of transfer mechanisms was associated with better transfer effectiveness. Third the type of HRM to be transferred needs to fit the specific needs of distributors within the supply chain; in practice the best fit for this part of the supply chain can be considered a mix of paternalistic and transaction HRM, rather than the so-called 'best' practice HRM. Finally although there was potential in principle for the underperforming supply chain to learn from the experiences and practices of the higher performing supply chains, the extent to which Company J was likely to be able to emulate the more successful chains was constrained by significant internal barriers to learning (for example the pressure for short-term gains and the time needed to build trust, the lack of internal HRM expertise and the lack of local decision-making authority). However, an even more major constraint on the learning process came from the dynamic changes in the aftermarket distribution system that had the potential even to disrupt the trust-based partnerships in the exemplar supply chains. Thus the scope for applying the lessons from past practice, which has been the major focus of the comparative investigation of the three supply chains, may be limited by both the variations in internal conditions and by the fact that the key challenges for future development may be different from those faced in the automotive aftersales market in the past.

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Bonett, Johan, Linda Silva, Gino Viacava, and Carlos Raymundo. "Integrated inventory system for forecasts based on knowledge management for the reduction of stock breaks in a distribution SME." Latin American and Caribbean Consortium of Engineering Institutions, 2019. http://hdl.handle.net/10757/656259.

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In the current market, there is a large number of SMEs that have a large margin of economic losses due to lack of stocks, due to the supply process. In other words, the lost sales and the costs of the services generated by not having their products available in their warehouses is a critical scenario in the distribution companies, whose added value lies in maximizing their level of customer service. To solve this problem, we propose a system that integrates the development of the attention and the model of the inventories of the periodic review, the bases based on the framework of the work. The results, after analyzing the demand, their patterns and choosing the best method to use, are antecedents to develop the management of inventories and their policies. Likewise, knowledge management will act as an integrated support. Through the simulation carried out for a distribution of lubricants, results were obtained that indicate a reduction of 93% in losses due to stock-outs and an increase in the service level that goes from 77% to 91%. This is an integrated system of interest to be applied as a solution for SMEs that have high stock-outs and lack this type of tools..

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Dissertations / Theses on the topic 'Knowledge partitioning and distribution'

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