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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Representing and Reasoning about Skills and Competencies over Time

Fazel-Zarandi, Maryam 09 January 2014 (has links)
To stay competitive within the market, organizations need to accurately understand the skills and competencies of their human resources to better utilize them and more effectively respond to internal and external demands for expertise. This is particularly important for most services organizations which provide a variety of products and services to multiple and changing clients. The ability to accurately locate experts is also important to knowledge workers. From this perspective, finding individuals with appropriate knowledge and skills is important for accomplishing knowledge intensive tasks and solving complex problems. This thesis focuses on the problem of representing and reasoning about skills and competencies over time for more effective human resources management and expert finding. Proper modeling of skills and competencies provides, among other things, a common language for assessments, a foundation for consistent interviewing, a linkage between performance management and learning, and a means for aligning business strategy and skills for driving organizational performance. It also improves knowledge management by making explicit what the organization knows and can perform. In this thesis, we present a framework for profiling human resources over time. In particular, we use first-order logic to represent and reason about expertise, skills and competencies and capture information about sources of skill and competency information. The framework provides: - a formal ontology for skill and competency management which specifies how individuals should be represented and evaluated against a skill, - a technique for inferring and validating skills and competencies over time using different sources of information, - a systematic way of evaluating human resources in order to provide a more efficient, structured, and consistent assessment process, and - techniques for identifying unreliable sources of information and revising trust in these sources. This work enhances the ability of organizations to better utilize their human assets and improves the task of expert finding required for accomplishing knowledge intensive tasks and solving complex problems.
332

Representing and Reasoning about Skills and Competencies over Time

Fazel-Zarandi, Maryam 09 January 2014 (has links)
To stay competitive within the market, organizations need to accurately understand the skills and competencies of their human resources to better utilize them and more effectively respond to internal and external demands for expertise. This is particularly important for most services organizations which provide a variety of products and services to multiple and changing clients. The ability to accurately locate experts is also important to knowledge workers. From this perspective, finding individuals with appropriate knowledge and skills is important for accomplishing knowledge intensive tasks and solving complex problems. This thesis focuses on the problem of representing and reasoning about skills and competencies over time for more effective human resources management and expert finding. Proper modeling of skills and competencies provides, among other things, a common language for assessments, a foundation for consistent interviewing, a linkage between performance management and learning, and a means for aligning business strategy and skills for driving organizational performance. It also improves knowledge management by making explicit what the organization knows and can perform. In this thesis, we present a framework for profiling human resources over time. In particular, we use first-order logic to represent and reason about expertise, skills and competencies and capture information about sources of skill and competency information. The framework provides: - a formal ontology for skill and competency management which specifies how individuals should be represented and evaluated against a skill, - a technique for inferring and validating skills and competencies over time using different sources of information, - a systematic way of evaluating human resources in order to provide a more efficient, structured, and consistent assessment process, and - techniques for identifying unreliable sources of information and revising trust in these sources. This work enhances the ability of organizations to better utilize their human assets and improves the task of expert finding required for accomplishing knowledge intensive tasks and solving complex problems.
333

1H NMR-based Metabolomics for Elucidating the Mode of Action of Ccontaminants in the Earthworm Eisenia Fetida after Sub-lethal Exposure

Lankadurai, Brian 08 August 2013 (has links)
There is a growing need to develop rapid and cost-effective ecotoxicological tools for risk assessment because traditional methods examine endpoints such as mortality, which do not provide any insight into the mode of action (MOA) of the chemical. Research presented within this thesis illustrates the potential of 1H NMR-based metabolomics as a rapid and routine ecotoxicological tool that can elucidate a chemical’s MOA and also aid in the identification of metabolites of exposure. Metabolomics involves measuring the fluctuations in the endogenous metabolites of an organism within a cell, tissue, bio-fluid or whole organism in response to an external stressor. We focused on the model polycyclic aromatic hydrocarbon (PAH) phenanthrene, and the perfluoroalkyl acids (PFAAs) perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), due to their recalcitrant nature and widespread prevalence in soil environments. 1H NMR-based metabolomics analysis of the exposure of Eisenia fetida earthworms to sub-lethal phenanthrene exposure via filter paper contact tests revealed a concentration-dependent two-phased MOA: a linear correlation between the metabolic response and exposure concentration at low concentrations followed by a plateau in the responses at high concentrations. Alanine, glutamate, maltose, cholesterol and phosphatidylcholine emerged as potential indicators of phenanthrene exposure. An increased energy demand and an interruption in the conversion of succinate to fumarate in the Krebs cycle were observed due to phenanthrene exposure. Sub-lethal PFOA and PFOS exposure to E. fetida via contact tests for two days revealed heightened responses with higher PFOA and PFOS concentrations. Leucine, arginine, glutamate, maltose, and ATP were identified as potential indicators of PFOA or PFOS exposure. E. fetida responses were then investigated after exposure for two, seven and fourteen days to an artificial soil that was spiked with sub-lethal PFOS concentrations. An exposure time-dependent operation of two separate MOAs were identified. Both the contact tests and artificial soil exposure studies identified an elevation in fatty acid oxidation, a disruption in energy metabolism and biological membrane structure, and also an interruption of ATP synthesis following PFOA and PFOS exposure. This thesis illustrates the promise of NMR-based metabolomics as a routine tool for ecotoxicological assessment of contaminated sites.
334

INTEGRATED GEOPHYSICAL INVESTIGATION OF KARST FEATURES – INNER BLUEGRASS REGION OF KENTUCKY

Frommel, Jamin C. 01 January 2012 (has links)
High-resolution electrical-resistivity, seismic-refraction, and seismic-reflection surveys were performed at three locations in the Inner Bluegrass Region of Kentucky along coincident survey lines in order to correlate results and determine which method is most effective at locating karst features in this area. The first two survey locations at Slack’s Cave and the Kentucky Horse Park were chosen in order to investigate known karst features. High and low electrical-resistivity anomalies were correlated to air- and water-filled karst voids, respectively. Seismic velocity anomalies, including parabolic time suppressions, amplitude terminations, and surface-wave backscatters, were also observed and correlated to these karst voids. These findings were applied to a third location along Berea Road in order to investigate undiscovered karst voids. Three seismic targets were selected based on backscatter anomaly locations and were aligned in a northwest trend following the general bedrock dip, joint orientations, and suspected conduit orientation. Overall, the seismic-reflection method provided the highest resolution and least ambiguous results; however, integration of multiple methods was determined to help decrease ambiguities in interpretation created by the inherent non-uniqueness found in the results of each method.
335

階層的可視化手法を用いたアソシエーション分析によるプロファイリング

MITSUMATSU, Sawako, FURUHASHI, Takeshi, YOSHIKAWA, Tomohiro, ITO, Akira, 光松, 佐和子, 古橋, 武, 吉川, 大弘, 伊藤, 晃 12 1900 (has links)
No description available.
336

Användarfokuserad utveckling av en mellanmålsdryck för skolelever / User-centric developments of a snack drink for school children

Nyman, Jesper, Yin, Niklas January 2014 (has links)
Examensarbetets syfte var att undersöka preferenser för olika mellanmålsdrycker, avsedda för skolbarn och som enbart var tillverkad av skånska vegetabilier. Ett ytterligare syfte var att studera lärares uppfattningar av elevernas koncentrationsförmåga under lektionstiden innan lunch. Som ett första led i att utse tre mellanmålsdrycker till ett preferenstest bland skolelever utfördes två konsensusprofileringar. Första profileringen utfördes med experter inom produktutvecklingsområdet där fyra dryckesprototyper profilerades och den andra profileringen utfördes med en studentpanel där 3 vidareutvecklade prototyper profilerades. Preferenstestet utfördes med barn som deltagare för att utse vilken av de tre prototypdryckerna som barnen ansåg som favorit. Favoriten skulle användas till ett projekt vid namn Skolskjutsen. För att ta reda på lärares uppfattning kring elevernas koncentrationsförmåga innan lunch utfördes en kvalitativ mailundersökning med sex deltagande lärare. Resultatet från profileringarna visade att prototyperna skiljde sig från varandra i fråga om egenskaperna utseende, doft, smak och konsistens. De två utvalda mellanmålsdryckerna från profilering 1 var båda söta och mindre sura, den nya framtagna prototypen som profilerades i profilering 2 ansågs både vara för sur och mindre söt i smaken. Preferenstestet visade att barnen signifikant föredrog svartvinbärsdrycken framför mixdrycken i smak, utseende och i helhet. Svartvinbärsdrycken var mer söt och mindre sur i smaken jämfört med mixdrycken. Det var endast ett fåtal av barnen som föredrog mixdrycken som var minst söt och mest sur i smaken.     Slutsatsen av preferenstestet är att majoriteten av barnen i studien föredrog drycker som smakar sött och inte allt för surt. För majoriteten av barnen är det smaken som är den avgörande faktorn. Lärarna anser att barnen är mest koncentrerade på skoldagens start och är minst koncentrerade sent på eftermiddagen. Lärarna som deltog i studien anser även att barnen är hungriga och mindre koncentrerade timmen innan lunch. De undviker att ha mer krävande lektioner som matte och svenska timmen innan lunchen. / The thesis aimed to examine preferences for different snack drinks for school children, and that alone was made from Scania vegetables. A further aim was to study teacher’s perceptions of students' ability to concentrate during class time before lunch. As a first step to appoint three snacks drinks to a preference test among school students were two consensus profiling conducted. First profiling was conducted with experts in the field where four beverage prototypes were profiled and the other profiling was performed with a student panel where three further developed prototypes were profiled. The preference test was conducted with children as participants to select which of the three prototype drinks the children considered favorites. The favorite would be used for a project called Skolskjutsen. To find out the teachers 'perception of students' ability to concentrate before lunch was performed a qualitative email survey with six participating teachers. The results from the profiling have showed that the prototype differed from each other in terms of characteristics appearance, aroma, flavor and texture. The two snack drinks from profiling one was both sweet and less sour, but the new developed prototype which was profiled in profiling 2 considered being too acidic and less sweet in taste. The preference test showed that children significantly preferred the black currant drink before the mix drink in taste, appearance and in full. Blackcurrant drink was sweeter and less acidic in flavor compared to the mix drink. There were only a few of the children who preferred the mix drink that was least sweet and most acidic in taste. The conclusion of the preference test is that the majority of children in the study preferred the beverages that taste sweet and not too acid. For the majority of children, it is the taste that is the determining factor. The teacher’s view that children are most concentrated on the start of the school day and is least concentrated in the late afternoon. The teachers who participated in the study also consider that the kids are hungry and less concentrated the hour before lunch. They avoid having more demanding classes as math and Swedish before lunch. / Skolskjutsen
337

The validation of an assessment battery for sales representatives in a telecommunication company / Antoinette Charlene Smith

Smith, Antoinette Charlene January 2006 (has links)
Globalisation yields numerous challenges and continuous changes in the economic environment, rapid technological advancements, and an increased emphasis on organisational competitiveness. The existing practice in the Telecommunications company relied on conventional recruitment-on-vacancy and training. In 1997, a customer contact research programme was launched to review the specific competencies underlying the full range of customer contact roles, in order to understand the constructs which would underlie effective assessment of people for the role of sales and marketing. The aim of this research was to evaluate the effectiveness of an assessment battery in a telecommunications company. The assessment battery measures the participants' essential skills, behaviour and performance to bring about critical development action. The Work Profiling System (WPS) and Subject Matter Experts in the Sales Division identified the fifteen competencies. The assessment battery consisted of Ability Tests: Verbal Evaluation (VCC3) and Numerical Evaluation (NCC4), and a personality questionnaire: Customer Contact Styles Questionnaire (CCSQ7.2). The Customer Contact Competency Inventory (CCCI) was electronically administered to the sales representatives' respective managers in 2006, to give objective 360" feedback. The study population (n=97) consisted of sales representatives working in a Telecommunication company. The objectives for this research were to validate the chosen selection battery for the sales representatives, and determine its relation to manager-rated performance. Descriptive and inferential statistics were used to analyse the data. Stepwise multiple regression analyses were carried out to determine whether the independent variables (CCSQ7.2 and Ability Tests) hold any predictive value regarding the dependent variable (CCCI). The results of the regression analyses showed that Verbal Evaluation (VCC3) was a significant predictor of: Convincing, Communicating Orally, Results Driven. Problem Solving and Organisation. Modest (R4) was a significant predictor of Convincing. Participative (R5) was a significant predictor of Problem Solving and Organisation. Overall, it can be stated that there is a significant relationship between the test battery and job performance. The results in this study reflect that correlations between personality, ability and performance were small to moderate. This is lower than expected and what is found in similar international research. This is probably due to the flawed criterion. The results should be used with caution to prevent making a Type I1 error. Recommendations for future research are made. vii / Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.
338

The use of data mining techniques in crime trend analysis and offender profiling

Adderley, Richard January 2007 (has links)
The aim of this project is to ascertain whether the data in existing Police recording systems can be used by existing mature data mining techniques in an efficient manner to achieve results that are more accurate than those achieved by Police specialists when analysing crime. The Police Service has no formalised methodology of recording and analysing crime data and it is incumbent on each Force to train and develop appropriate personnel to provide operational analysis. Police data is inconsistent and, frequently, incomplete making the task of formal analysis far more difficult and current analytical practices are semi-manual and time consuming producing results of limited accuracy. These analytical processes would benefit from using data mining techniques within a structured approach as discussed within this thesis. The usage of supervised and unsupervised learning techniques within a structured methodology to mining Police data is evaluated. The research demonstrates that data mining techniques can be successfully used in operational policing. High volume crimes such as burglary that have been committed by one or more known offenders can be classified and the model used to attribute currently undetected crimes to one or more of those known offenders. Burglary crimes that previously had no overt relationship and the identity of the offender is unknown can be clustered with the ability to suggest one or more offenders who may be responsible for committing the crime. The same techniques used in analysing high volume crime can be used to link low volume major crimes such as serious sexual assaults. The recognised benefits include an improvement in the accuracy of results over current semi-manual processes and a reduction in the time taken to achieve those results.
339

Interpreting the human transcriptome

Werne Solnestam, Beata January 2015 (has links)
The human body is made of billions of cells and nearly all have the same genome. However, there is a high diversity of cells, resulted from what part of the genome the cells use, i.e. which RNA molecules are expressed. Rapid advances within the field of sequencing allow us to determine the RNA molecules expressed in a specific cell at a certain time. The use of the new technologies has expanded our view of the human transcriptome and increased our understanding of when, where, and how each RNA molecule is expressed. The work presented in this thesis focuses on analysis of the human transcriptome. In Paper I, we describe an automated approach for sample preparation. This protocol was compared with the standard manual protocol, and we demonstrated that the automated version outperformed the manual process in terms of sample throughput while maintaining high reproducibility. Paper II addresses the impact of nuclear transcripts on gene expression. We compared total RNA from whole cells and from cytoplasm, showing that transcripts with long, structured 3’- and 5’-untranslated regions and transcripts with long protein coding sequences tended to be retained in the nucleus. This resulted in increased complexity of the total RNA fraction and fewer reads per unique transcript. Papers III and IV describe dynamics of the human muscle transcriptome. For Paper III, we systematically investigated the transcriptome and found remarkably high tissue homogeneity, however a large number of genes and isoforms were differentially expressed between genders. Paper IV describes transcriptome differences in response to repeated training. No transcriptome-based memory was observed, however a large number of isoforms and genes were affected by training. Paper V describes a transcript profiling protocol based on the method Reverse Transcriptase Multiplex Ligation-dependent Probe Amplification. We designed the method for a few selected transcripts whose expression patterns are important for detecting breast cancer cells, and optimized the method for single cell analysis. We successfully detected cells in human blood samples and applied the method to single cells, confirming the heterogeneity of a cell population. / Människokroppen är uppbyggd av miljarder celler och nästan alla innehåller samma arvsmassa. Trots detta finns det många olika celler med olika funktioner vilket är en följd av vilken del av arvsmassan som cellerna använder, dvs vilka RNA-molekyler som finns i varje cell. Den snabba utvecklingen av sekvenseringstekniker har gjort det möjligt att studera när, var och hur varje RNA-molekyl är uttryckt och att få en djupare förståelse för hur människans celler fungerar. Arbetet som presenteras i denna avhandling fokuserar på analys av RNA-molekyler i människans celler. I artikel I beskriver vi en automatiserad metod för att förbereda cellprov för RNA-sekvensering. Det automatiserade protokollet jämfördes med det manuella protokollet, och vi visade att det automatiserade protokollet överträffade det manuella när det gällde provkapacitet samtidigt som en höga reproducerbarheten behölls. I artikel II undersökte vi effekterna som RNA-molekyler från en del av cellen (cellkärnan) har på den totala mängden uttryckta RNA-molekyler. Vi jämförde RNA från hela cellen och från en del av cellen (cytoplasman) och visade att RNA-molekyler med långa och strukturerade 3'- och 5'-otranslaterade regioner och RNA-molekyler med långa proteinkodande sekvenser tenderade att hållas kvar i cellkärnan till en högre grad. Detta resulterade i en ökad komplexitet av RNA-molekylerna i hela cellen, medan vi i cytoplasma-fraktionen lättare kunde hitta de korta och svagt uttryckta RNA-molekyler. I Artikel III och IV studerar vi RNA-molekyler i människans skelettmuskler. I artikel III visar vi att andelen RNA-molekyler uttryckta i skelettmuskler är väldigt lika mellan muskler och mellan olika personer, men att ett stort antal RNA-molekyler var uttryckta i olika nivåer hos kvinnor och män. Artikel IV beskriver RNA-nivåer som svar på upprepade perioder av uthållighetsträning. Artikel V beskriver en metod för att studera ett fåtal utvalda RNA-molekyler. Vi valde RNA-molekyler vars uttryck är viktigt vid analys av bröstcancerceller, och optimerade metoden för analys av enskilda celler. Vi analyserade cancerceller från blodprov och använde metoden för att titta på RNA-nivåer i enskilda celler från en grupp av celler och visade på skillnader i RNA-nivåer inom gruppen. / <p>QC 20150115</p>
340

Predicting Treatment Response and the Role of the ISG15/USP18 Ubiquitin-like Signaling Pathway in Hepatitis C Viral Infection

Chen, Limin 14 February 2011 (has links)
Hepatitis C Virus (HCV) infects 170 million people worldwide. The current treatment regimen, which is combination therapy with pegylated interferon (PegIFN) and Ribavirin (Rib), cures only 50% of the patients infected with the most prevalent HCV genotype. Therefore, there is a pressing need to understand the molecular mechanism of interferon resistance and to develop a prognostic tool to predict who will respond to treatment before initiation of therapy. It has been firmly established that the virus-host interaction plays an important role in determining treatment outcomes. My thesis investigated the host factors that are involved in interferon resistance with an aim to provide insights into the molecular mechanism of IFN resistance. cDNA microarray analysis identified 18 differentially expressed hepatic genes from pretreatment liver tissues of responders (Rs) and non-responders (NRs). Based on the differential expression levels of these 18 genes, a prognostic tool was developed to predict who will respond to therapy, with a positive predicting value (PPV) of 96%. Most of these 18 genes are interferon stimulated genes (ISGs) and they are more highly expressed in NR livers, indicating that preactivation of interferon signaling in the pre-treatment liver tissues contributes to NR. 3 out of the 18 genes are involved in an ubiquitin-like ISG15/USP18 signaling pathway that plays an important role in interferon response. Over-expression of USP18 and ISG15 in the pretreatment liver tissues of NR promotes HCV production and blunts interferon anti-HCV activity. There exists a distinct cell-type specific ISG activation in the pretreatment liver tissues of Rs and NRs. Up-regulation of the two ISGs that I tested (ISG15 and MxA) was found mainly in hepatocytes in NRs while ISG activation was preferentially observed in macrophages in Rs. Taking all these data together, pre-activation of interferon signaling and cell-type specific gene activation in the pretreatment liver tissues of patients infected with HCV are associated with treatment non-response. HCV exploits the host interferon system to favour its persistence by enhanced replication /secretion stimulated by a few ISGs (ISG15, USP18) in response to IFN. The developed prognostic tool can be used to stratify patients for treatment and the novel insights of the molecular mechanism of IFN resistance in HCV patients offer potential drug targets for future development.

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