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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

An Economic Evaluation of the Health and Environmental Benefits of the Integrated Pest Management Program (IPM CRSP) in the Philippines

Cuyno, Leah Marquez 08 June 1999 (has links)
Concern about externalities associated with pesticide use in developing countries has motivated the development of integrated pest management (IPM) programs in these areas. In the Philippines, the IPM Collaborative Research Support Program (IPM CRSP) was established to specifically address the widespread misuse of pesticides in the rice-vegetable systems of Nueva Ecija, one of the major rice and onion producing regions in the country. IPM CRSP initiatives include research on the optimal use of pesticides, complementary weed control strategies, and alternative cultural and biological controls. If successful, the program should generate benefits that can be measured in economic terms. These benefits include improvements in water quality, food safety, pesticide applicator safety, and long run sustainability of pest management systems. This study was designed to measure the health and environmental benefits of the IPM CRSP in the Philippines. A survey questionnaire was administered to 176 onion farmers in five villages in Nueva Ecija to identify farm and farmer characteristics, pesticide usage, pest management practices, perceptions about pesticide hazards, awareness of IPM strategies, and willingness to adopt specific technologies being developed under the IPM CRSP. In addition, a contingent valuation survey was used to elicit farmers' willingness-to-pay to avoid risks posed by pesticides to different environmental categories. A comprehensive economic measure of the benefits of IPM CRSP was derived by 1) assessing the hazards associated with pesticide usage, 2) providing an ex ante measure of program impacts on pesticide usage, 3) predicting IPM adoption rates, and 4) estimating society's willingness-to-pay to avoid the health and environmental risks from pesticides under Philippine conditions. A measure of the amount of risks avoided as a result of IPM CRSP adoption was combined with farmers' willingness to pay bids for risk avoidance to derive a monetary value of the program benefits. The estimated economic benefits of the IPM CRSP to farmer residents in 5 villages in Nueva Ecija amount to 230,912.00 pesos for one onion season. / Ph. D.
22

Assessing Farm-Level and Aggregate Economic Impacts of Olive Integrated Pest Management Programs in Albania: an Ex-Ante Analysis

Daku, Lefter S. 25 April 2002 (has links)
Concerns about the harmful effects of pesticides on the environment, human health, and wildlife have led to research and promotion of integrated pest management (IPM) strategies. Recently, an IPM program was introduced in the Albanian olive sector through the USAID-funded global IPM-CRSP project to develop improved olive IPM technologies. This study develops and applies a protocol for integrated economic impact assessment of olive pest management strategies designed by the IPM-CRSP project in Albania. The main components of the integrated approach for economic impact assessment of olive IPM include (i) net return analysis for measuring farm level impacts; (ii) economic surplus modeling for measuring market-level impacts; and (iii) modeling of IPM adoption under output uncertainty. The economic surplus equilibrium displacement model developed for the Albanian olive market with no international trade accounts for IPM research-induced supply shifts, increased demand due to quality improvement, and research-induced spillovers to non-target zones. The main sources of data for performing partial budgeting and economic surplus analysis were: (i) an expert survey; (ii) partial budgets compiled based on a farmer survey and expenditure records from field-level experiments; and (iii) data collected at the market level. The data used to estimate the dichotomous logit model came from a 1999 survey of 200 growers and a survey of 120 growers carried out in 2000 in the Vlora district of Albania. The net return analysis indicates that compared to conventional practices, the proposed olive IPM packages generally promise higher yields, improved quality of olive products, lower pesticide use, and higher net returns to producers. However, adoption of some of the IPM practices implied higher production costs. Based on the simulation results, the Albanian olive industry has the potential to derive a net IPM research benefit between $39 million (assuming that farmers move directly from minimum spraying to IPM) and $52 million (assuming that farmers move from full pesticide program to IPM) over the next 30 years. Farmers' reliance on pesticide use on olives and other crops does not seem to hinder IPM adoption. Grower perceptions and the process of expectation formation significantly influence adoption decisions. Addressing the process of expectation formation and changing these perceptions by educational programs and better access to information will encourage IPM adoption. / Ph. D.
23

Economic Impact Assessment of IPM CRSP Activities in Bangladesh and Uganda: A GIS Application

Debass, Thomas 19 October 2001 (has links)
The purpose of this study is to assist planners and scientists in assessing the economic implications of the USAID-funded Integrated Pest Management-Collaborative Research Support Program (IPM CRSP) research activities. The study presents a framework and a set of procedures for documenting, evaluating and communicating aggregate economic impacts of IPM technologies within targeted areas and across agro-ecological regions. Performing an economic impact assessment involves consideration of many factors, from the adoption patterns of IPM technologies to the level of benefits and costs producers and consumers can reap from their adoption. Adopting the framework and procedures outlined in this study will help ensure that economic benefits of IPM CRSP activities are consistently and comprehensively evaluated and documented. The assessment process involves identifying and defining alternative pest management strategies, data and information collection, and analytical procedures. Two case studies are carried out to demonstrate the functionality and practical nature of the framework. Partial budgeting and ex-ante economic surplus analysis are employed to estimate the aggregate benefits of IPM CRSP strategies in Bangladesh and Uganda. In Bangladesh, an altered schedule of hand weeding in cabbage production and Neem leaf powder as an insecticide for eggplants were selected for assessment. In Uganda, the maize variety Longe-1 and seed dressing with Endosulfan for management of bean fly and root rot on beans, are evaluated. Also, a Geographic Information System (GIS) is used to project the transferability of IPM CRSP strategies beyond the primary sites. Data on production, consumption, prices, price elasticities for demand and supply, and experiment costs are gathered and refined to derive aggregate benefits for each country. Expert questionnaires were developed to determine adoption rates, and to elicit information about yield and cost changes due to the adoption of these technologies. Agro-ecological and socio-economic data were collected to facilitate the spatial framework and examine adoption rate patterns. The GIS analysis gives insight into the spatial dimension of economic analysis and complements the effort of the IPM CRSP to globalize its activities. The research findings show that the IPM practices investigated gave a substantial amount of benefits discounted over thirty years to both consumers and producers. This study has shown that IPM CRSP-induced pest management practices in Bangladesh and Uganda are viable and more profitable production practices than existing farmer practices. Efforts to promote the adoption of these technologies will likely result in more efficient production and greater economic rewards for the farmers, consumers, and in turn for the country as a whole. Finally, the study presents recommendations for further research relating to gender and cross-border trade issues to strengthen the functionality of the framework. / Master of Science
24

Cross-commodity Guidelines for Neonicotinoid Insecticides in Arizona

Palumbo, John C., Ellsworth, Peter C., Dennehy, Timothy J. 05 1900 (has links)
4 pp. / Arizona enjoys a sustained recovery from the devastating whitefly outbreaks of the early 1990's. This success is built on an IPM strategy that includes the use of selective and effective chemistry. Admire has been a key soil insecticide protecting vegetables and produce throughout Arizona and is the first member of a burgeoning class of chemistry known as the neonicotinoids. New members of this valuable, reduced-risk, class of chemistry are now available to agricultural producers, placing a burden on users of these compounds to adopt rational plans for sustaining their efficacy. This consensus document represents our best guess efforts to limit and share this chemistry among different agricultural interests. Our goal is to preserve the long-term efficacy of the neonicotinoids and protect growers' interests in sustainable and economical whitefly management. Through identification of crop communities (i.e., "multi-crop", "cotton-intensive", and "cotton/melon") common to Arizona agriculture, we have sculpted sensible plans of use that should allow access to this valuable chemistry for everyone, while protecting it from resistance.
25

Improvement of the in-cycle speed fluctuation and system efficiency of an auxiliary power unit

Liu, Dian January 2016 (has links)
Well reported problems around air quality and climate change, together with the energy crisis resulting from finite fossil fuel resources is motivating all the automotive manufacturers to develop new propulsion systems through electrification and hybridisation. The range extended electric vehicle (REEV) is one of these solutions that seeks a practical compromise between the on-board battery size and the one-charge driving range. The auxiliary power unit (APU) is the key component in a REEV and is designed to maintain the battery charge for long distance trips. Since the APU does not propel the vehicle, it only requires a small capacity engine with low-cylinder-count. This type of engine exhibits severe speed fluctuations due to its low firing frequency. As the engine and the M/G are isolated from the vehicle driving wheels, it is possible to use the electric machine to deliver a counteracting torque to the engine reducing the resultant torque spikes and thus the system speed oscillation but likely to increase the electric losses. This research work aims to minimise the speed fluctuation balanced against the extra losses introduced. A Dynamic Torque Control (DTC) strategy was designed and tested on an APU using a novel approach to achieve this target. The system components were modelled individually regarding to the prototype system specifications, which is developed within a collaborative R&D project. The empirical engine model was calibrated with extensive bench testing data to recreate the in-cycle torque waveforms. The motor/generator was modelled as a novel hybrid between an analytical model and an FEA model which allowed the winding inductance variation due to the current rise to be included in the model. This approach was designed to replicate the electric machine performance with high fidelity whilst keeping the computational time and cost low. With the help from the system model, the DTC torque demand patterns were designed based on detailed analysis of the contribution factors of the speed fluctuation and the electric machine losses. A unique Pareto Curve of the speed fluctuation reduction and the electrical loss was identified during the analysis and allowed the optimal demand pattern to be developed for a given torque capability electric machine. The simulation results showed that the system in-cycle speed fluctuations could be reduced by 16.4% and 19.11% at 2000rpm full load and 4500rpm full load condition respectively while the electric specific fuel consumption (ESFC) rose by 2.26% and 1.35% at the same operation points. The DTC strategy was implemented in the prototype APU and successfully tested on the rig at 2000rpm and 4500rpm. A reduction in the speed oscillation and the ESFC increase consistent with the simulation results were observed. The simulation estimates on ESFC was proved within an error of 2.19%. This research improves the insight into the mechanisms that are responsible for increased losses when dynamic torque control is used and develops an optimisation approach which takes account of these factors. When an electric machine, which does not have the same instantaneous peak torque capability as the engine, is used in an APU, a better compromise between speed fluctuation smoothing and system efficiency can be achieved.
26

Seletividade de inseticidas recomendados para a produção integrada de citros sobre o parasitoide Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) / Selectivity of insecticides recommended for integrated citrus production on the parasitoids Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae)

Beloti, Vitor Hugo 21 January 2014 (has links)
Apesar de o Brasil ser um dos principais produtores de laranja no mundo e o maior exportador de suco concentrado, atualmente a cultura vem sofrendo perdas em razão do ataque de diversas pragas e doenças, sendo a principal o Huanglongbing (HLB), ou Greening, que foi relatada pela primeira vez em 2004 no estado de São Paulo. Essa doença está associada às bactérias do gênero \"Candidatus Liberibacter sp.\", sendo que no Brasil ocorrem as bactérias \"Ca. Liberibacter asiaticus\" e \"Ca. Liberibacter americanus\", tendo como seus vetores o psilídeo Diaphorina citri, praga importante devido a sua distribuição geográfica e características biológicas. Existe registro de cerca de 50 espécies da família Rutaceae, que incluem as espécies do gênero Citrus (laranjas, limões, limas, etc.), que podem hospedar esse inseto, além da murta (Murraya paniculata). Na natureza, D. citri é controlado por uma série de fatores, podendo ser outros insetos, fungos ou até condições climáticas desfavoráveis para seu desenvolvimento. Porém, os resultados de pesquisas indicam que ectoparasitoide Tamarixia radiata é eficiente no controle de D. citri. Entretanto, levantamentos realizados nos últimos anos verificaram que o parasitismo natural vem sendo reduzido consideravelmente, devido, principalmente, à aplicação intensiva de agroquímicos. Dessa forma, a utilização de produtos seletivos, ou seja, que atue contra o psilídeo D. citri e tenha o menor impacto possível sobre o parasitoide T. radiata é imprescindível para o sucesso do manejo integrado de pragas em que se utiliza o controle químico juntamente com a liberação do parasitoide. Assim, objetivou-se com esse trabalho: 1) Estudar o efeito direto e a persistência de inseticidas sobre o parasitoide T. radiata; 2) Estudar o efeito de inseticidas sobre a fase pupal do parasitoide; 3) Determinar a interferência dos inseticidas na capacidade de parasitismo; 4) Avaliar a toxicidade diferencial dos inseticidas para o parasitoide T. radiata e para o psilídeo D. citri. Dos 25 inseticidas testados no efeito direto, 20% foram considerados inócuos (classe 1); 12% levemente nocivo (classe 2); 12% moderadamente nocivo (classe 3); e 56% como nocivo (classe 4). Apesar de vários serem nocivos para adultos do parasitoide, apenas Lorsban® 480 BR e Perfekthion® afetaram a emergência do parasitoide quando pulverizados sobre a sua fase de pupa, sendo que os demais permitiram a emergência e não afetaram a duração, razão sexual e longevidade. No teste de persistência, 25% dos inseticidas testados foram considerados de vida curta (classe 1); 37,5% como levemente persistentes (classe 2); 29,2% moderadamente persistentes (classe 3); e apenas 8,3% persistentes (classe 4). Portanto, para a escolha de um inseticida para controle de pragas dos citros, deve-se levar em consideração seu efeito no adulto, fase imatura e sua persistência biológica na planta. / Although Brazil is one of the major orange producers and largest exporter of juice concentrate in the world, currently the citrus culture suffers losses due to the attack of several pests and diseases. Huanglongbing (HLB), or Greening, is the main disease and it was first reported in 2004 in the State of São Paulo, Brazil. This disease is associated with bacteria of the genus \"Candidatus Liberibacter sp.\", and in Brazil the bacteria \"Ca. Liberibacter asiaticus\" and \"Ca. Liberibacter americanus\" occur, and the psyllid Diaphorina citri is its main vector, an important pest insect because of its geographical distribution and biological characteristics. There is record of about 50 species of the family Rutaceae, including the species of the genus Citrus (oranges, lemons, limes, etc.) that can host this insect, in addition to orange jasmine (Murraya paniculata). In nature, a number of factors control D. citri, namely other insects, fungi or even adverse weather conditions for their development. However, studies show that the ectoparasitoid Tamarixia radiata is efficient in the control of D. citri. However, recent studies indicate that natural parasitism has been reduced considerably, mainly due to the intensive application of pesticides. Thus, the use of selective products, i.e., which act against the psyllid D. citri with the lowest possible impact on the parasitoids T. radiata is indispensable for the success of the integrated pest management that uses chemical control along with the release of parasitoids. Thus, the objectives of this work were: 1) to study the direct effect and the persistence of insecticides on the parasitoid T. radiata; 2) to investigate the effect of insecticides on the pupal stage of the parasitoids; 3) to determine the effect of insecticides on parasitism capacity; 4) to assess the differential toxicity of insecticides to the parasitoid T. radiata and psyllid D. citri. Of the 25 insecticides tested in terms of direct effect, 20% was considered harmless (class 1); 12% slightly harmful (class 2); 12% moderately harmful (class 3); and 56% as harmful (class 4). Although several are harmful to adult of the parasitoid, only Lorsban® 480 BR and Perfekthion® affected the emergence of the parasitoid when sprayed in the pupal stage, and the others allowed the emergence and did not affect the duration, sex ratio and life span. In the test of persistence, 25% of the insecticides were considered short life (class 1); 37.5% slightly persistent (class 2); 29.2% moderately persistent (class 3); and only 8.3% persistent (class 4). Therefore, choosing an insecticide for control of pests of citrus requires consideration of its effect on adults, immature phase and their biological persistence in the plant.
27

Toxicidade e efeito subletal dos principais inseticidas utilizados na cultura da soja para Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) / Toxicity and sublethal effect of the main insecticides used in soybean crop to Trichogramma pretiosum (Hymenoptera: Trichogrammatidae)

Paiva, Ana Clara Ribeiro de 16 February 2016 (has links)
Helicoverpa armigera é uma espécie que até 2013 era considerada praga quarentenária A1 no Brasil. Tratamentos com inseticidas são indispensáveis para o manejo de H. armigera em quase todas as culturas do mundo. Uma alternativa à utilização de inseticidas sintéticos para o controle de pragas é o uso de parasitoides do gênero Trichogramma. Em consideração a grande quantidade de aplicações de agroquímicos no sistema de produção de grãos, torna-se essencial avaliar a seletividade dos inseticidas utilizados, garantindo informações que auxilie na manutenção do T. pretiosum na área, podendo potencializar o controle biológico de H. armigera, sendo isto, importante para o estabelecimento do manejo integrado de pragas nas grandes culturas. Portanto, objetivou-se com esse trabalho: estudar a toxicidade aguda e a persistência de inseticidas sobre o parasitoide; estudar o efeito de inseticidas sobre a fase pupal do parasitoide; determinar a interferência dos inseticidas na capacidade de parasitismo. Dos inseticidas testados em condições laboratoriais, Nomolt®, Avatar®, Belt®, Premio® e Intrepid® foram considerados inócuos para adultos. Lorsban® e Engeo Pleno® são nocivos à fase de pupa, enquanto Acefato®, Pirate® e Belt® apesar de inócuos afetam as gerações seguintes. Pirate®, Lorsban® e Engeo Pleno interferem na capacidade de parasitismo, e Acefato® tem efeito deletério na geração que tem contato com o resíduo. Os inseticidas Nomolt®, Avatar®, Belt®, Acefato®, Premio® e Intrepid® foram classificados como inseticidas de vida curta (classe 1). Lorsban® tem efeito moderadamente persistente (classe 3) e Engeo Pleno® e Pirate® classificados como persistentes (classe 4). Portanto, visando um bom programa de MIP, deve-se optar pelo uso de inseticidas seletivos, ou inseticidas nocivos para adultos do parasitoide podem ser utilizados no campo desde que estes não estejam ocorrendo naturalmente ou que não coincida com épocas de liberação do mesmo. / Helicoverpa armigera is a specie that until 2013 was considered A1 quarantine pest in Brazil. Treatments with insecticides are indispensable for the management of H. armigera in almost every crops in the world. An alternative to the use of synthetic insecticides for pest control is the use of parasitoids of the genus Trichogramma. Considered the large number of agrochemical applications in grain yield, it is essential assess the selectivity of insecticides used, providing informations to assist in the maintenance of T. pretiosum in the area and can enhance the biological control of H. armigera, this being important for the establishment of integrated pest management in field crops. Therefore, the aim of this work was study the acute toxicity and the duration of the harm effects of insecticides on the parasitoid, study the effect of insecticides on the pupal stage of the parasitoid and determine the interference of insecticides on the parasitism capacity. Insecticides tested in laboratory conditions, Nomolt®, Avatar®, Belt®, Premio® and Intrepid® were considered innocuous to the adults. Lorsban® and Engeo Pleno® were harmful to the pupal stage, while Acefato®, Pirate® and Belt® although were considered innocuous they affect the next generations. Pirate®, Lorsban® and Engeo Pleno® interfered on the parasitism capacity, and Acefato® have a deleterious effect on the generation that has contact with the insecticide residue. The insecticides Nomolt®, Avatar®, Belt®, Acefato®, Premio® and Intrepid® were classified as short live (class 1). Lorsban® was moderately persistent (class 3) and Engeo Pleno® and Pirate® were classified as persistent (Class 4). Therefore, for an effective IPM program, it is important to use the selective insecticides. Insecticides that were harmful to the parasitoid adults could be used in the field, provided that the parasitoids do not occur naturally and the chemical applications do not coincide with the parasitoids release.
28

Summary Conclusions on Computational Experience and the Explanatory Value of Condition Measures for Linear Optimization*

Ordóñez, Fernando, Freund, Robert M. 01 1900 (has links)
The modern theory of condition measures for convex optimization problems was initially developed for convex problems in conic format, and several aspects of the theory have now been extended to handle non-conic formats as well. In this theory, the (Renegar-) condition measure C(d) for a problem instance with data d=(A,b,c) has been shown to be connected to bounds on a wide variety of behavioral and computational characteristics of the problem instance, from sizes of optimal solutions to the complexity of algorithms. Herein we test the practical relevance of the condition measure theory, as applied to linear optimization problems that one might typically encounter in practice. Using the NETLIB suite of linear optimization problems as a test bed, we found that 71% of the NETLIB suite problem instances have infinite condition measure. In order to examine condition measures of the problems that are the actual input to a modern IPM solver, we also computed condition measures for the NETLIB suite problems after pre-preprocessing by CPLEX 7.1. Here we found that 19% of the post-processed problem instances in the NETLIB suite have infinite condition measure, and that log C(d) of the post-processed problems is fairly nicely distributed. Furthermore, there is a positive linear relationship between IPM iterations and log C(d) of the post-processed problem instances (significant at the 95% confidence level), and 42% of the variation in IPM iterations among the NETLIB suite problem instances is accounted for by log C(d) of the post-processed problem instances. / Singapore-MIT Alliance (SMA)
29

Monitoring populations of the flour beetles Tribolium confusum Jacquelin du Val and Tribolium castaneum (Herbst) in flour mills and in laboratory settings

Hawkin, Karen 14 July 2008 (has links)
This thesis reports the effects of disturbance and harbourage on the fitness of Tribolium confusum and T. castaneum, as well as the the efficacy of pheromone monitoring traps for monitoring for populations of Tribolium in laboratory and mill settings. Behavioural studies were also carried out on mill and laboratory-reared beetles and the distributions of both species in a mill were examined. Twenty-four hour sieving disturbance decreased the rates of dispersal for both species, and decreased T. castaneum fecundity. Rolling disturbance decreased T. confusum dispersal rate while shaking disturbance decreased T. castaneum dispersal rate. When undisturbed beetles were given differing amounts of flour in the presence or absence of harbourage, beetles laid more eggs in larger amounts of flour, but harbourage only affected T. castaneum at one level of flour (2 g). Throughout disturbance and harbourage experiments, T. castaneum laid more eggs than T. confusum. Pheromone monitoring traps placed in three Canadian flour mills were not useful in predicting the degree of infestation inside Simons rollstands. Pheromone monitoring traps also showed low efficacy (i.e. caught few beetles) in both mill and laboratory settings, and T. confusum was caught less often than T. castaneum in both mills and in a warehouse. Mill-strain beetles of both species were caught less often than laboratory-strain beetles in a warehouse. In one Canadian flour mill, both T. castaneum and T. confusum were found inside rollstands but the two species were spatially segregated from one another, rarely being found together in the same rollstand. In contrast to this, both species were consistently found together in samples taken from the same mill less than a year beforehand. In behavioural laboratory studies, beetles collected directly from a mill moved slower than beetles collected from a laboratory culture and this response was shown to be phenotypic. Mill-strain and laboratory-strain beetles also differed in burrowing tendencies, with T. confusum from the laboratory strain burrowing less than T. confusum from a mill and T. castaneum from different mills sometimes burrowing more and sometimes less than T. castaneum from the laboratory strain. / October 2008
30

Bats

Gouge, Dawn, Li, Shujuan, Nair, Shaku 07 1900 (has links)
11 pp. / This document provides a general overview of bat biology and behavior with emphasis on urban environments, use of integrated pest management (IPM) techniques that are in keeping with bat conservation guidelines, and disease awareness and prevention efforts.

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