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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.
21

Enhanced dissolved organic matter recovery from saltwater samples with coupled electrodialysis and solid phase extraction

Chambers, Luke Russell 07 January 2016 (has links)
Complexities associated with dissolved organic matter (DOM) isolation from seawater have hampered compositional characterization of this key component of global carbon and nutrient cycles. Two techniques, Electrodialysis (ED) and Solid Phase Extraction (SPE), were combined to more effectively isolate DOM from salt-containing waters. Sample recovery was optimized and evaluated on a range of samples including coastal ocean seawater, open ocean seawater, artificial seawater from cultures of marine phytoplankton, and artificial seawater samples containing standard compounds of different molecular sizes and charge. ED was performed with a system optimized for processing 2 to 10 L sample volumes and SPE was performed using Bond Elut PPL exchange resin. With the combination of ED and PPL techniques an average recovery of 76.7 ± 2.6% was obtained for natural coastal seawater. Comparison of C/N ratios and fluorescence excitation emission matrices (EEMs) taken at the beginning and end of the recovery process indicated that the final recovered material was representative of the DOM present in the original samples.
22

The role of collective action in the provision of agri-environmental public goods: theoretical development through case studies in Italy

Vanni, Francesco <1976> 24 July 2012 (has links)
The thesis aims at analysing the role of collective action as a viable alternative to the traditional forms of intervention in agriculture in order to encourage the provision of agri-environmental public goods. Which are the main benefits of collective action, in terms of effectiveness and efficiency, compared to traditional market or public intervention policies? What are the drivers that encourage farmers to participate into collective action? To what extent it is possible to incorporate collective aspects into policies aimed at providing agri-environmental public goods? With the objective of addressing these research questions, the thesis is articulated in two levels: a theoretical analysis on the role of collective action in the provision of public goods and a specific investigation of two local initiative,s were an approach collective management of agro-environmental resources was successfully implemented. The first case study concerns a project named “Custodians of the Territory”, developed by the local agency in Tuscany “Comunità Montana Media Valle del Serchio”, which settled for an agreement with local farmers for a collective provision of environmental services related to the hydro-geological management of the district. The second case study is related to the territorial agri-environmental agreement experimented in Valdaso (Marche), where local farmers have adopted integrated pest management practices collectively with the aim of reducing the environmental impact of their farming practices. The analysis of these initiatives, carried out through participatory methods (Rapid Rural Appraisal), allowed developing a theoretical discussion on the role of innovative tools (such as co-production and co-management) in the provision of agri-environmental public goods. The case studies also provided some recommendations on the government intervention and policies needed to promote successful collective action for the provision of agri-environmental public goods. / La tesi si pone l’obiettivo di valutare il ruolo delle azioni collettive come una valida alternativa alle classiche forme di intervento in agricoltura, in particolare quelle volte ad incentivare la fornitura di beni pubblici ambientali. Quali sono i vantaggi delle azioni collettive, in termini di efficacia ed efficienza, rispetto alle classiche misure pubbliche o agli incentivi di mercato? Quali sono i drivers che spingono gli agricoltori a partecipare a progetti collettivi legati ai beni pubblici agro-ambientali? Attraverso quali strumenti di policy e quali assetti istituzionali è possibile favorire lo sviluppo di azioni collettive? Con l’obiettivo di rispondere a queste domande di ricerca, la tesi si articola su due livelli: un’analisi teorica sul ruolo delle azioni collettive nella fornitura dei beni pubblici e un’indagine specifica di due iniziative locali, dove si è sperimentato un approccio collettivo alla gestione delle risorse agro-ambientali. Il primo caso di studio riguarda il progetto denominato “Custodia del territorio”, sviluppato dall’ente gestore del comprensorio di Bonifica Media Valle del Serchio (Toscana), che prevede un accordo tra questo ente pubblico e gli agricoltori locali per la gestione idro-geologica del territorio in cui operano. Il secondo caso riguarda l’accordo agroambientale della Valdaso (Marche), dove gli agricoltori locali hanno adottato collettivamente pratiche di lotta integrata avanzata con l’obiettivo di ridurre l’impatto delle loro pratiche agricole sull’ambiente. L’analisi di queste iniziative, svolta attraverso metodologie partecipative (Rapid Rural Appraisal), ha permesso di sviluppate una riflessione teorica sul ruolo di strumenti innovativi (come co-produzione e co-gestione) alla gestione delle risorse agro-ambientali e di fornire raccomandazioni sul design e l’implementazione di politiche che possano favorire azioni collettive associate ai beni pubblici agro-ambientali.
23

Assessing Household Food Waste in Italy: A Methodology for Detecting Drivers and Quantities

Giordano, Claudia <1986> January 1900 (has links)
It has been estimated that one third of edible food destined for human consumption is lost or wasted along the food supply chain globally. Much of the waste comes from Global North, where consumers are considered as the bigger contributors. Different studies tried to analyze and estimate the Household Food Waste (HFW), especially in UK and Northern Europe. The result is that accurate studies at national level exist only in UK, Finland and Norway while no such studies are available in Italy, except for survey- based researches. Though, there is a widespread awareness that such methods might be not able to estimate Food Waste. Results emerging from literature clearly suggest that survey estimate inferior amounts of Food Waste as a result, if compared to waste sorting and weighting analysis or to diary studies. The hypothesis that household food waste is under-estimated when gathered through questionnaires has been enquired into. First, a literature review of behavioral economics and heuristics has been proposed; then, a literature review of the sector listing the existing methodologies to gather national data on Household Food Waste has been illustrated. Finally, a pilot experiment to test a mixed methodology is proposed. While literature suggests that four specific cognitive biases might be able to affect the reliability of answers in questionnaires, results of the present experiment clearly indicate that there is a relevant difference between how much the individual thinks to waste and he/she actually does. The result is a mixed methodology based on questionnaire, diary and waste sorting, able to overcome the cons of each single method.
24

Development of New Methodologies for Prediction of Performances of Asphalt Mixtures

Lamperti, Riccardo <1986> 27 May 2016 (has links)
This thesis proposes the use of new methodologies for prediction of performances of asphalt mixtures. Recent improvements in technology make it possible to adopt new methods of investigation with the dual objective of improving the performance in the survey of the parameters and investigate new properties so far not analyzed. In particular, the image analysis and the tyre/surface interaction belong to an innovative framework, which is next to flank, if not replace, the classic measurements so far employed. The thesis deals with the use of these technologies for the analysis of three rubberized stone mastic asphalts, which were laid on a stretch of road close to Bologna, Italy. Three different surveys were carried out on site during the first year of service. The surveys included the change in texture and skid resistance due to the traffic, along with the acoustic properties of the pavement. Local as well as dynamic continuous measurements were carried out, involving the use of a profilometer and a skiddometer. A second phase involved the prediction of the surface parameters with different stages of simulated trafficking on Road Test Machine. At each stage change in macrotexture, skid resistance, adhesion between bitumen and aggregates, contact pressures and areas were assessed. The image analysis is used for the assessment of the adhesion between the bitumen and the aggregate. The images are then processed in order to create 3D models of the asphalt specimens and investigate the surface and volume properties. The tyre/pavement interaction is another fundamental phenomena that received little considerations from the research, given its importance. A final discussion summarizes these investigations by separately review three different simulated periods, i.e. the early life, the in-service equilibrium and the end of life. In order to accelerate the distress, one slab was subjected to Immersion Wheel Track test.
25

Food Supply Chains and Eva.CAN Model: a Network Analytic Approach

Clemente, Flavia <1970> 12 May 2016 (has links)
The research work leading to the drafting of this PhD thesis approaches the analysis of supply chains of products of animal origin from various productive species by using network analytic methods. In the studied analysis six supply chains are embedded in a single model which highlights all the interconnections that have little evidence in traditional models. This new model that we called Eva.CAN (Evaluation of Complex Agri-food Network Model) is a new concept model, the first complex network model for the agri-food production, the first to allow the application of Network Theory analysis methods. The initial hypothesis is that the various supply chains of products of animal origin have to be interpreted and analyzed as a whole, as a single complex system. The complex network is studied analyzing the adjacency matrix that constitutes the network with algorithms and methods extensively tested and validated. This analytical approach has already been applied with positive results in many research areas such as social networks, transport networks, the stylistic of writers and musicians, proteomics, pharmacology, medicine, biology, and many others. We apply this methodology to supply chains of products of animal origin and show a series of preliminary results. This method of study of food supply chains could be useful for an observatory, bringing to light slightly evident relations and becoming a strong support for policy-makers. It can also provide useful advices to individual actors on how to optimize their own supply chains. Finally, through an effective enumeration and evaluation of the relationships, a network model could be helpful in design of tracking and traceability systems.
26

Evaluation of Ecosystem Services production under different Agricultural Policy Scenarios

Chatzinikolaou, Parthena <1983> 12 May 2016 (has links)
The objective of this study is to test a methodology for the classification of areas according to the provision of ecosystem services (ES) and for the evaluation of the effects of different agricultural policy scenarios on such classification. The framework was applied to the classification of the 26 municipalities of the province of Ferrara, Italy. The case study area can be considered a traditional cultural landscape, characterised by historical-cultural sites, agricultural areas and protected areas of natural importance. The evaluation focuses on the different categories of ES and applies a set of indicators available from secondary data sources assessing different aspects of ES. From the policy perspective, the context was represented by the pre-2014 CAP and represented the Baseline scenario. In the next stage, the model simulated a New CAP scenario, based on the measures of the RDP 2014-2020 that are addressed on restoring and enhancing ecosystems. The classification approach in each of the two scenarios was implemented under two weighting solutions. As a general remark, it is observed that the provision of ES varies greatly from one municipality to the next. All the municipalities offer a significant number of provisioning and cultural services, mainly connected to recreational opportunities. From the experience carried out in this study, we can conclude that the application of the PROMETHEE, in particular with the integration of the weights for the ES indicators, has shown the potential to support the characterisation of agricultural land in terms of the provision of multiple ES. The study presents MCDA as a suitable tool to illustrate the differences in the provision of ES in different case study areas. To some extent, in spite of the limitations of this work, this also applies to analyzing the consequences of different agricultural policy scenarios in the provision of these services.
27

Economics of vector-borne diseases prevention: The case of the Tiger Mosquito control and Chikungunya and Dengue prevention plan in the Emilia-Romagna region (Northern Italy)

Rivas Morales, Stefano <1985> 14 June 2016 (has links)
Aedes albopictus is considered one of the most invasive mosquito species in the world. It has proved capacity for local transmission of Chikungunya and Dengue within Europe. This research evaluated public costs related to the implementation of the plan for Ae. albopictus control and Chikungunya and Dengue prevention set up in Emilia-Romagna region (Northern Italy), where a Chikungunya epidemic outbreak occurred in 2007, with 217 confirmed cases. The management plan started in 2008 by involving more than 280 municipalities and 4.3 million inhabitants within the region, and its activities mainly target the ecological conditions for the multiplication of infestation hotspots in urban areas, to reduce the probability of rapid and uncontrolled disease spreading in case of outbreaks. The study accessed to data on the expenditures supported by all the public institutions involved in the implementation of the management plan. During the 8 year’s life of the management plan, the public authorities of the region spent at least € 37.7 million for the Ae. albopictus control, although the yearly expenditure declined since the € 7.6 million of 2008 to the € 3.1 million of 2015. The assessment of this expenditure revealed a high level of variability of its costs in the various municipalities included in the plan, not easily explainable only by the territorial and environmental differences among the urban areas. The cost for the treatment of a single road drain varied in a range from ≈ € 0.04 to ≈ € 6.1 among the municipalities in the years of existence of the plan. The research also attempted a first evaluation of the expenditures incurred by households to protect themselves from mosquito bites. During the pilot phase of a dedicated project, 57 interviews were realized to a random sample, and the mean expenditure € 18.25 per household.
28

Analysis of the FADN system implementation in the Republic of Serbia

Ivkov, Ivana <1980> 12 May 2016 (has links)
One among many other preconditions in the field of agriculture for Serbia’s accession to the EU is establishment of the Farm Accountancy Data Network (FADN) system. It can improve both on-farm and agricultural policy decision making processes by providing valuable information on physical, structural, economic and financial data. Republic of Serbia does not have farm accounting legal base and therefore the agricultural hold-ers are not obliged to keep records in order to have accurate income calculations. In line with this, Serbian FADN system has been established. As a consequence to aforementioned, this deliverable is an earliest attempt to examine the use-fulness and suitableness of the FADN system implementation in the Republic of Serbia. The applied EU FADN methodology is described, clarifying the basic definitions (universe of agri-cultural holdings, field of observation, sample selection, standard output, etc.). Harmonization and application of this methodology in the Republic of Serbia is described as well. In this research it was observed Serbian FADN life cycle from 2012 to 2015, with the main focus on 2013. Comparative research method was used in a particular areas of this study, which aimed to make comparisons across different FADN organizational infrastructures of certain EU Member States and Republic of Serbia, as well as to make comparisons of the first Serbian FADN results with the same results of a few selected EU Member States. In the pre-conclusion section the emphases is given on SWOT analyses, which gives an assessment of the FADN system implementation in the EU and in the Republic of Serbia. In addition to this, recommendations are given in order to achieve better FADN system implementation in the Repub-lic of Serbia. Research findings indicated that the Serbian FADN system is still under development, faces many challenges, and needs to be further improved and strengthened.
29

Hospital Admission from the Emergency Department for Patients Diagnosed with Heart Failure

Young, Tammy 01 January 2019 (has links)
Approximately 25% of those hospitalized with congestive heart failure are readmitted within 30 days after discharge. Because researchers and policy makers consider hospital readmission within 30 days for patients with heart failure to be a quality of care issue, the Centers for Medicare and Medicaid Services has imposed financial penalties of up to 3% of a hospital's Medicare revenue for 1 year for excessive readmissions, potentially impacting the financial sustainability of some organizations. The purpose of the study was to address the research gap regarding the outcome quality measure of hospital admissions from the emergency department (ED) and 2 each process and structure variables. The Donabedian conceptual framework was used to assess quality of care through the triad of structure, process, and outcome. The quantitative study comprised analysis of cross-sectional archival data from the 2015 National Hospital Ambulatory Care Survey using cross-tabulations with chi-square followed by multiple logistic regression analysis. Findings showed that process quality measures of being seen in the ED within 72 hours and total laboratory tests obtained in the ED were predictive of lower likelihood of admission. The structure quality measure of insurance was not predictive; however, being seen by provider type consulting physician was predictive of higher likelihood of admission, whereas being seen by a nurse practitioner was predictive of lower likelihood of hospital admission. The implications of this study for social change are helping hospitals maintain financial stability through avoidance of financial penalties for heart failure readmission, supporting access to care for patients by avoiding hospital closures.
30

Ekologisk dagvattenhantering : - ett anpassat och utarbetat ekologiskt dagvattensystem för kvarteret Limkokaren/Oden, Hässleholm, Hässleholms kommun, Skåne län

Petersson, Sofie January 2013 (has links)
Kvarteret Limkokaren/Oden, Hässleholm, Skåne, skall bebyggas och förtätas. Hässleholms Vatten AB, har ställt kravet att den avrinningsvolym som får komma från området efter byggnation inte får överstiga 1 l/s ha. Hela området är på ca 2 hektar. Genom att bebygga ett område förändras avrinningsvolymen och -hastigheten för dagvattnet. Mer hårgjorda ytor minskar också möjligheten för nederbörden att infiltrera och återgå till grundvattnet. På så sätt förändras den naturliga vattencykeln. Genom att imitera naturen och återskapa naturliga områden i bebyggelse kan ökad nederbördsinfiltrering rekonstrueras och volym- och hastighetsavrinningen reduceras. Ekologisk dagvattenhantering (ED) bygger på att återskapa den naturliga vattencykeln. För området har olika ED komponenter, så som bioretentions- och bevuxna diken, infiltrationsplanteringar och dammar, använts för att framförallt uppnå målet för avrinningsvolymen men även ge en viss rening av dagvattnet samt skapa en omväxlande, behaglig och välkomnande utemiljö. Resultatet utgörs av ett förslag till väl fungerande ED system som klarar de krav som finns och som har byggts upp utifrån situationsplanen för kvarteret och med hänsyn tagna till de naturliga förutsättningar området har. Osäkerheten kring de olika ED komponenternas verkliga kapacitet att reducera stora delar utav ett Q100 regn har ifrågasatts. Det är troligt att den beräknade avrinningen som sker i samband med ett större regn är direkt underskattad. Diskussion om hur ökad avrinningsvolym skall hanteras har framlett till förslag på att ytterligare marköversvämning i parkområden kan vara nödvändigt. Genom att använda ekologisk dagvattenhantering har avrinningsvolymen till kommunalt ledningsnät begränsats samtidigt som området kan användas för rekreation, lek och lärande. Ekologisk dagvattenhantering är ett bra alternativ för kvarteret Limkokaren/Oden men kan även användas i andra områden med andra ändamål än volymreduktion. / The quarter Limkokaren/Oden in the center of Hässleholm, Sweden, is going to be developed and more densely populated. In order to get permission to build on this area there are requirements from the sewage company, Hässleholms Vatten AB. The requirements concern the storm water volume that can be accepted to enter the drainage system. This runoff volume from the area should not exceed 1 l/s and hectare after the construction work has been finished. The whole area is about 2 hectares. The development will result in a change of storm water runoff in both volume and velocity. More paved surfaces will reduce the ability for the storm water to infiltrate and return to the groundwater. In this way the natural water cycle will change. By mimicking nature and build natural runoff and infiltration areas in between the settlements the infiltration of storm water can be increased and in the same time the runoff volume and velocity can be reduced. Ecological storm water management (ED) is based upon the idea to recreate the natural water cycle. In these study bioretention swales, swales, infiltration plantings and dams have been proposed as different ED components that can be used to reach the requirement. Calculations have been made in order to reach the requirements with using the right components for the ED system. These components also give the local environment a pleasant and inviting appearance and at the same time contribute with some cleaning of the storm water. The result should be a good working ED system that manage the requirement for the runoff volume. The system is designed by the situation map and by the natural conditions of the area. But is the ED components ability to reduce the runoff volume in the same order as the calculations? The reduction capacity of the system in case of a smaller rain is probably in the same order as the calculations. For a large rain event the runoff volume will be much larger and in order to handle the bigger volume it is proposed that flooding the green areas in the quarter should be allowed. Ecological storm water management is a good alternative for this area but can also be used in other places with different requirements.

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