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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.
101

Nutrient diagnosis of orange crops applying compositional data analysis and machine learning techniques / Diagnóstico de nutrientes na cultura da laranjeira aplicando análise composicional dos dados e técnicas de inteligência artificial

Yamane, Danilo Ricardo [UNESP] 29 November 2018 (has links)
Submitted by Danilo Ricardo Yamane (danilo_yamane@yahoo.com.br) on 2019-01-28T17:15:40Z No. of bitstreams: 1 Tese Yamane (2018).pdf: 2814108 bytes, checksum: f2e102e5809427e8d3d26d0a59971542 (MD5) / Approved for entry into archive by Tatiana Camila Gricio (tatiana.gricio@unesp.br) on 2019-01-28T17:32:17Z (GMT) No. of bitstreams: 1 yamane_dr_dr_jabo.pdf: 2814108 bytes, checksum: f2e102e5809427e8d3d26d0a59971542 (MD5) / Made available in DSpace on 2019-01-28T17:32:17Z (GMT). No. of bitstreams: 1 yamane_dr_dr_jabo.pdf: 2814108 bytes, checksum: f2e102e5809427e8d3d26d0a59971542 (MD5) Previous issue date: 2018-11-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O manejo eficiente de nutrientes é crucial para atingir alta produtividade de frutos. Resultados da análise do tecido são comumente interpretados usando faixas críticas de concentração de nutrientes (CNCR) e Sistema Integrado de Diagnose e Recomendação (DRIS) em culturas de laranja. No entanto, ambos os métodos ignoram as propriedades inerentes à classe dos dados composicionais, não considerando adequadamente as interações de nutrientes e a influência varietal na composição nutricional da planta. Portanto, ferramentas eficazes de modelagem são necessárias para corrigir vieses e incorporar efeitos genéticos na avaliação do estado nutricional. O objetivo deste estudo foi desenvolver uma abordagem diagnóstica precisa para avaliar o estado nutricional de variedades de copa de laranjeira (Citrus sinensis), usando a análise composicional dos dados e algoritmos de inteligência artificial. Foram coletadas 716 amostras foliares de ramos frutíferos em pomares comerciais de laranjeiras não irrigadas (“Valência”, “Hamlin”, “Pera”, “Natal”, “Valencia Americana” e “Westin”) distribuídos pelo estado de São Paulo (Brasil), analisadas as concentrações de N, S, P, K, Ca, Mg, B, Cu, Zn, Mn e Fe, e avaliadas as produções de frutos. Balanços de nutrientes foram computados como relações-log isométricas (ilr). Análises discriminantes dos valores de ilr diferenciaram os perfis de nutrientes das variedades de copa, indicando composições nutricionais específicas. A acurácia diagnóstica dos balanços de nutrientes atingiu 88% com a produtividade de corte correspondente a 60 t ha-1, utilizando-se ilrs e o algoritmo de classificação knn, o que possibilitou o desenvolvimento de padrões nutricionais confiáveis para a obtenção de elevado nível de produtividade de frutos. Os citricultores do estado de São Paulo devem adotar o conceito de balanços de nutrientes, onde grupos de nutrientes estão equilibrados de maneira ideal. Fornecer mais Ca através de calcário ou gesso, reduzir as aplicações de fertilizantes P e K, e aumentar a fertilização de B via solo pode reequilibrar os balanços [Mg | Ca], [Ca, Mg | K], [P | N, S], [K, Ca, Mg | N, S, P] e [B | N, S, P, K, Ca, Mg] em pomares de laranjas com produtividade inferior a 60 t ha-1. O software “CND-Citros” pode auxiliar os citricultores, engenheiros agrônomos e técnicos a diagnosticar o estado nutricional das lavouras de laranja com base no método proposto, utilizando os resultados da análise química das folhas. / Efficient nutrient management is crucial to attain high fruit productivity. Results of tissue analysis are commonly interpreted using critical nutrient concentration ranges (CNCR) and Diagnosis and Recommendation Integrated System (DRIS) on orange crops. Nevertheless, both methods ignore the inherent properties of compositional data class, not accounting adequately for nutrient interactions and varietal influence on plant ionome. Therefore, effective modeling tools are needed to rectify biases and incorporate genetic effects on nutrient composition. The objective of this study was to develop an accurate diagnostic approach to evaluate the nutritional status across orange (Citrus sinensis) canopy varieties using compositional data analysis and machine learning algorithms. We collected 716 foliar samples from fruit-bearing shoots in plots of non-irrigated commercial orange orchards (“Valencia”, “Hamlin”, “Pera”, “Natal”, “Valencia Americana” and “Westin”) distributed across São Paulo state (Brazil), analyzed N, S, P, K, Ca, Mg, B, Cu, Zn, Mn and Fe, and measured fruit yields. Sound nutrient balances were computed as isometric log-ratios (ilr). Discriminant analysis of ilr values differentiated the nutrient profiles of canopy varieties, indicating plant-specific ionomes. Diagnostic accuracy of nutrient balances reached 88% about cutoff yield of 60 Mg ha-1 using ilrs and a k-nearest neighbors classification, allowing the development of reliable nutritional standards at high fruit yield level. Citrus growers from São Paulo state should adopt the concept of yield-limiting nutrient balances, where groups of nutrients are optimally balanced. Supplying more Ca as lime or gypsum materials, reducing the P and K fertilizer applications and enhancing soil B fertilization could re-establish the [Mg | Ca], [Ca, Mg | K], [P | N, S], [K, Ca, Mg | N, S, P] and [B | N, S, P, K, Ca, Mg] balances in orange orchards yielding less than 60 Mg ha-1. The software “CND-Citros” can assist citrus growers, agronomy engineers and technicians to diagnose the nutrient status of orange crops based on the proposed method, using the results of leaf chemical analysis.
102

Deux points de vue sur les variétés de Fano : géométrie du diviseur anticanonique et classification des surfaces à singularités 1/3(1,1) / Two viewpoints on Fano varieties : geometry of the anticanonical divisor and classification of surfaces with 1/3(1,1) singularities

Heuberger, Liana 23 June 2016 (has links)
Cette thèse concerne l'étude des variétés de Fano, qui sont des objets centraux de la classification des variétés algébriques. La première question abordée concerne les variétés de Fano lisses de dimension quatre. On cherche a étudier les potentielles singularités d'un diviseur anticanonique de sorte qu'on puisse les écrire sous une forme locale explicite. En tant qu'étape intermédiaire, on démontre aussi que ces points sont au plus des singularités terminales, c'est-à-dire les singularités les plus proches du cas lisse du point de vue de la géométrie birationnelle. On montre ensuite que ce dernier résultat se généralise en dimension arbitraire en admettant une conjecture de non-annulation de Kawamata.De façon complémentaire, on s¿intéresse à des variétés de Fano de dimension plus petite, mais admettant des singularités. Il s¿agit des surfaces de del Pezzo ayant des singularités de type 1/3(1,1). Ceci est l'exemple le plus simple de singularité rigide, c'est-à-dire qui reste inchangée à une déformation Q-Gorenstein près. On classifie entièrement ces objets en trouvant 29 familles. On obtient ainsi un tableau contenant des modèles de ces surfaces, qui pour la plupart sont des intersections complètes dans des variétés toriques. Ce travail s'inscrit dans un contexte plus large, qui a pour cible de calculer leur cohomologie quantique pour ensuite vérifier si deux conjectures en symmetrie miroir. / This thesis concerns Fano varieties, which are central objects within the classification of algebraic varieties.The first problem we discuss involves smooth Fano varieties of dimension four. We study the potential singularities of an anticanonical divisor and determine their explicit local expression. As an intermediate step, we show that they are terminal points, that is the singularities which are closest to the smooth case from the point of view of birational geometry. We then show that the latter result generalizes in arbitrary dimension if we suppose that a nonvanishing conjecture of Kawamata holds.The second approach is to examine Fano varieties of smaller dimensions which admit singularities. The objects we consider are log del Pezzo surfaces with 1/3(1,1) points. This is the simplest example of a rigid singularity, that is it remains unchanged under Q-Gorenstein deformations. We give a complete classification of these surfaces, finding 29 families. We also provide a table describing almost all of them as complete intersections in toric varieties. This work belongs to an overarching project that aims at studying mirror symmetry for del Pezzo surfaces with cyclic quotient singularities.
103

A Comparative Analysis of the Ingestion and Storage Performance of Log Aggregation Solutions: Elastic Stack & SigNoz

Duras, Robert January 2024 (has links)
As infrastructures and software grow in complexity the need to keep track of things becomes important. It is the job of log aggregation solutions to condense log data into a form that is easier to search, visualize, and analyze. There are many log aggregation solutions out there today with various pros and cons to fit the various types of data and architectures. This makes the choice of selecting a log aggregation solution an important one. This thesis analyzes two full-stack log aggregation solutions, Elastic stack and SigNoz, with the goal of evaluating how the ingestion and storage components of the two stacks perform with smaller and larger amounts of data. The evaluation of these solutions was done by ingesting log files of varying sizes into them while tracking their performance. These performance metrics were then analyzed to find similarities and differences. The thesis found that SigNoz featured a higher CPU usage on average, faster processing times, and lower memory usage. Elastic stack was found to do more processing and indexing on the data, requiring more memory and storage space to allow for more detailed searchability of the ingested data. This also meant that there was a larger storage space requirement for Elastic stack than SigNoz to store the ingested logs. The hope of this thesis is that these findings can be used to provide insight into the area and aid those choosing between the two solutions in making a more informed decision.
104

An Analysis of Mark-Recapture Data from Coded Wire Tagging of Hatchery Raised Salmon Using Log-Linear Models and Graphics / An Analysis of Mark-Recapture Data

Green, Philip 09 1900 (has links)
In this report mark-recapture data are analyzed with the use of weighted log-linear models, mosaics, and computer drawings of fish. The data are from salmon hatcheries, subsequent returns to the hatcheries and commercial catches of salmon. The log-linear models were used to study the effects of several variables on catches and returns. It is shown that these variables may have opposite effects depending on the brood year of the fish, that hatchery returns and commercial catches do not respond in the same way to the variables, and that more research is needed to determine the causes of the brood year differences. The mosaics and fish drawings were used to study the migration of the salmon in the ocean. The results confirm that chinook salmon decrease their food intake during the return trip to the hatchery, and they are consistent with theories of ocean migration of other species of salmon. / Thesis / Master of Science (MSc)
105

An Analysis on the Coverage Distance of LDPC-Coded Free-Space Optical Links

Luna, Ricardo, Tapse, Hrishikesh 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / We design irregular Low-Density Parity-Check (LDPC) codes for free-space optical (FSO) channels for different transmitter-receiver link distances and analyze the error performance for different atmospheric conditions. The design considers atmospheric absorption, laser beam divergence, and random intensity fluctuations due to atmospheric turbulence. It is found that, for the same transmit power, a system using the designed codes works over much longer link distances than a system that employs regular LDPC codes. Our analysis is particularly useful for portable optical transceivers and mobile links.
106

Konstruktion av "log strike"-testrigg för utombordsmotorer

Helgesson, Fredrik January 2016 (has links)
Projektet, som har utförts på uppdrag av Cimco Marine AB i Ängelholm, har haft som huvudmål att ta fram en testrigg för att ”log stirke”-testa utombordsmotorer. Cimco Marine AB har utvecklat en dieseldriven utombordsmotor för främst professionellt bruk. Dieselmotorn som används är en motor från bilindustrin som marinkonverterats och monterats på ett egenutvecklat underhus, där kraften från motorn överförs till propellern via två kuggremmar. ”Log strike” är när en utombordsmotor försedd båt kör över en stock som flyter i vattenytan. När detta händer uppstår en kollision mellan den del av utombordaren som sticker ner i vattnet och stocken. Om detta sker i hög hastighet induceras stora krafter i utombordaren och båten. För att säkerställa att Cimco Marine AB:s utombordsmotor klarar de påfrestningar som detta innebär vill de kunna testa detta i en testrigg. Man kan likna detta test med de krocktester som utförs inom bilindustrin. Den inledande fasen i projektet var att undersöka tillgänglig information om liknande tester. Det bestämdes sedan att riggen skulle bestå av en vagn som sköts mot utombordarens underhus och att vagnen således motsvarade stocken. Utifrån detta delades konstruktionen upp i olika enheter och varje enhet behandlades var för sig innan de sattes samman till en helhet. Konstruktionsarbetet har följt Fredy Olssons konstruktionsmetoder, princip- och primär konstruktion. Resultatet av projektet är en konceptkonstruktion på en ”log strike”-testrigg anpassad efter Cimco Marine AB:s krav och önskemål. / The goal for this project, carried out with directions from Cimco Marine AB, has been to design a concept construction for a “log strike” testrig for outboard motors. Cimco Marine AB has developed a diesel powered outboard motor mainly for professional use. The diesel engine used is an engine from the automotive industry that has been converted for marine use. The engine is located on a gearbox and underhouse that transfer the power via two belts down to the propeller. A “log strike” occurs when a boat with an outboard motor runs over a log floating in the surface of the water. When this happens a collision between the part of the outboard motor under the waterline and the log is a fact. To ensure that the outboard motor manufactured by Cimco Marine AB manage the loads a high speed log strike produces, they want a test rig to test this. One can compare this test with the crash tests performed in the vehicle industry. In the beginning of the project, time was spent on research and information gathering. It was then decided that the rig should consist of a sled that is propelled against the underhouse of the outboard motor. After this, the project was split in smaller units and every unit was considered separately before they were put together again as a whole. The construction project has followed the design method developed by Fredy Olsson. The end result is a concept design of a “log strike”- test rig, adapted to the requirements set up by Cimco Marine AB.
107

USING PACKET TELEMETRY (CCSDS) FOR MISSILE PROGRAM TO ACHIEVE FLEXIBILITY AND COST REDUCTIONS

Askeland, Arvid, Haukeli, Tom Rune 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / New Norwegian anti-ship missile program (NSM) has evaluated both the fixed format and the packet telemetry for its log/telemetry system. It is important that the NSM log system is easy to reconfigure, since the system shall be used during debugging, lab testing, system testing, test firings, and later on for operational evaluation firings. The packet telemetry standard has been selected because the packet telemetry provides dynamics and flexibility for changes, which are not easy to achieve with fixed format. Test results and system experience will be available before October and a summary will be presented at the ITC 2000 conference.
108

Spatial regression-based model specifications for exogenous and endogenous spatial interaction

LeSage, James P., Fischer, Manfred M. 03 September 2014 (has links) (PDF)
Spatial interaction models represent a class of models that are used for modeling origin destination flow data. The interest in such models is motivated by the need to understand and explain the flows of tangible entities such as persons or commodities or intangible ones such as capital, information or knowledge between regions. The focus here is on the log-normal version of the model. In this context, we consider spatial econometric specifications that can be used to accommodate two types of dependence scenarios, one involving endogenous interaction and the other exogenous interaction. These model specifications replace the conventional assumption of independence between origin-destination-flows with formal approaches that allow for two different types of spatial dependence in flow magnitudes. (authors' abstract) / Series: Working Papers in Regional Science
109

The effect of the number of log sorts on mechanised log processing productivity and value recovery in landing-based cable yarder harvesting operations

Tolan, Alexander Charles January 2014 (has links)
The New Zealand forest industry produces a diverse range of log grades and sorts to meet domestic and export market demands and to maximise returns to the forest grower. An implication for the supply chain is the number of log grades and sorts a harvesting operation is expected to produce from one species, radiata pine (Pinus radiata). The number of log grades and sorts can impact on landing size and layout requirements, value recovery, log-making complexity, machine utilisation and quality control requirements. A study was conducted to investigate if the number of log sorts affects mechanised log processing productivity and value recovery. This would determine if any gross value gains derived from producing a higher number of sorts are offset by losses in log processing productivity. Two landing-based mechanised log processors at cable yarder harvesting operations were studied using different cutting scenarios producing five, nine, twelve and fifteen log sorts. The study collected data from over 26 hours of mechanised processing which included the processing of 578 stems at an average piece size of approximately 1.6 m³. Machine utilisation results showed processors spending 84% of total time on productive tasks and that 49% of total time was spent on the primary productive tasks of log processing. Quadratic regressions were used to model log processing productivity trends which showed piece size and cutting scenario as significant predictor variables (p-value <0.01). There was a significant difference between cutting scenario with five log sorts and the cutting scenarios with twelve and fifteen log sorts (p-values <0.05), as well as a significant difference between the nine and fifteen log sort cutting scenarios (p-value <0.01). There was not enough evidence to suggest productivity was different between cutting scenarios producing five and nine log sorts. Based on this analysis, it was likely that the null hypothesis that the number of log sorts does not affect log processing productivity should be rejected. At a piece size of 2 m³, the productivity model estimated processing productivity was 10% higher producing nine log sorts compared to producing fifteen log sorts. A linear regression model showed a strong relationship between gross value recovery, piece size and cutting scenario (p-value <0.01). Gross value recovery increased as the number of log sorts increased. A significant model suggested it is likely null hypothesis 2, that the number of log sorts does not affect gross value recovery, should be rejected. There were only some differences in variances between cutting scenarios which were statistically significant. Both the average results and regression estimates showed the five log sort cutting scenario recovering 94% of the value of the cutting scenario with fifteen log sorts. Incremental gains in value recovery as the number of log sorts increased were marginal, which appeared to be due to log prices for many major log grades trading in a close range in relation to historic price trends. Regression trends for productivity and gross value recovery indicated that the most optimal cutting scenario, in terms of processing value outturn per productive machine hour, was the cutting scenario producing nine log sorts. This suggests that declines in processor productivity offset gains in gross value recovery when producing twelve and fifteen log sorts. Market sensitivity analysis suggested that differentials in log prices impact on the number of log sorts which optimise the value outturn per productive machine hour from log processing.
110

Validation of a Redwood Sequoia Sempervirens (D. Don) Endl Butt Log Sawing Simulator

Ashford, Sheridan January 2013 (has links)
Redwood (Sequoia sempervirens (D. Don) Endl.) has been identified as a species with considerable potential for plantation forestry in New Zealand. Investment decisions in high value alternate species must be based on accurate wood quality and value predictions. There is an opportunity to extend non-destructive evaluation tools available to redwood growers, and to present the outputs of the growth model by log products and sawn timber. A redwood pruned buttlog sawing simulator has been developed however the simulator had not been tested with real data. Twelve redwood trees from Mangatu estate were selected for a sawing study; these logs were reconstructed and run through the sawing simulator. Computerised log processing was used to produce simulated pruned log sawing outturn from the redwood Buttlog Sawing Simulator, and results were compared to real results from a sawing study. The objective of the study was therefore to determine how well the simulator matched volume and grade out-turn from twelve logs. This study found the many inconsistencies between simulated data and real data; particularly related to log size. While this study was unsuccessful in validation of the redwood sawing simulator, it provides initial insight into the simulators strengths and short comings.

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