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Maragos, Spyridon A. (Spyriodon Apostolos). "Yield management for the maritime industry." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/12031.
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Mak, Chung Yu. "Revenue impacts of airline yield management." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/26838.
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Sa, Joao. "Reservations forecasting in airline yield management." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14906.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1987.MICROFICHE COPY AVAILABLE IN ARCHIVES AND AERO.
Bibliography: leaves 116-117.
by Joao Sa.
M.S.
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Abrahams, Michael (Michael G. ). "Estimating yield curve noise." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118001.
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Thesis: S.M. in Management Research, Massachusetts Institute of Technology, Sloan School of Management, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 27-29).
In this paper, I explore methods for estimating noise in the yield curve. I evaluate optimization methods for fitting yield curves using the Nelson-Siegel model where recommendations in the literature remain unclear. I provide open source code on Github including contributions to the QuantLib C++ financial library.
by Michael Abrahams.
S.M. in Management Research
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Schumpf, Etienne. "Preisgerechtigkeit Grenzen des Yield Management bei Airlines /." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/05603220001/$FILE/05603220001.pdf.
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Aizikovitz, Jacob. "Yield protection as a risk management strategy." Thesis, Kansas State University, 2018. http://hdl.handle.net/2097/38662.
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Master of AgribusinessDepartment of Agricultural Economics
Christine Wilson
Risk management is critical in crop production as the challenges farmers face on a year to year basis are quite variable due to Mother Nature. There are many tools a farmer can utilize to help manage risk such as crop insurance and forward contracting or hedging. In recent years with lower prices, these tools have been more heavily used than they were a few years ago when corn and soybean prices were $8 and $15 per bushel, respectively. Margins in crop production are tight when market prices are low and input prices are high relative to market prices, and due to land cost. In order for farmers to produce greater profit, they must find ways to lower expenses or produce more bushels to increase their revenue. As margins tighten, farmers typically try to lower expenses to be more profitable rather than trying to increase bushels that would ultimately increase their revenue. When farmers try to reduce expenses, agricultural retailers experience lower revenues holding all else equal; distributors have lower revenues because the retailer is not selling as much, and the manufacturers experience lower revenues because the retailer and distributor are not moving the inventory compared to when farmer margins are larger. This thesis examines how yield protection for grain corn can be utilized as a risk management tool for crop production farmers. This thesis explores how increasing bushels and ultimately increasing revenue by protecting the bushels the crop is physically able to produce, can help manage producer risk. This thesis uses yield protection as a tool alongside crop insurance and marketing, rather than as a tool to replace crop insurance or marketing. Data used for yield protection is replicated fungicide, fungicide with an adjuvant, and fungicide with insecticide, that were evaluated against the untreated check over multiple locations and years across the Midwestern United States. Fungicide data were chosen because it is truly the definition of yield protection, protecting the crop against disease. Fungicides are usually the first products cut from a farmer’s crop production program to help reduce expenses and maintain profitability as margins tighten. The results found in this study are consistent with work conducted at Iowa State University. Results exhibited an increase in corn yield, but were not consistently statistical significant across treatments and location. In conclusion, the average yield increase was not enough over multiple years to pay for itself, and it lacked sufficient evidence. Yield protection does not fit a risk management strategy annually. However, yield protection should be utilized when specific thresholds on disease or insects are present to warrant this strategy.
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Cooney, Mackenzie C. "Yield-Curve Momentum." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/cmc_theses/2244.
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It has been twelve years since the last time the yield curve was inverted. Since 2017, the yield curve has been continuing to flatten and has almost entered an inverted state. The last five recessions have been preceded by the inversion of the yield curve. I examine momentum trading strategy’s ability to outperform during an inverted yield curve state. The yield curve can enter the momentum portfolio strategy through the portfolio’s formation and holding period. I document the increased performance of the momentum strategy’s total portfolio return in an inverted state. These results have implications on the timing a momentum trading strategy might be implemented.
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He, Yuanjie. "Tradeoffs and Random Yield in Supply Chain Management." online version, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1121438339.
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McGill, Jeffrey I. "Optimization and estimation problems in airline yield management." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/30652.
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This thesis addresses problems of optimization and estimation encountered in the process
of airline yield management, also called airline seat inventory control. Optimality conditions are given for the problem of setting booking limits for multiple, stochastically independent demand classes that are booked in a nested fashion into a fixed pool of airline seats. These optimality conditions are compared with the approximations given by the EMSR method. Additional conditions are given for two stochastically dependent fare classes, and extensions are made that allow for incorporation of passenger goodwill and upgrades of passengers between fare classes. The model developed for the dependent
demand case is also applied to the problem of determining an optimal overbooking limit in a single fare class. Finally, a methodology is developed for using multivariate multiple regression in conjunction with the EM method to estimate the parameters of demand distributions on the basis of historical demand data that have been censored by the presence of booking limits.Business, Sauder School of
Operations and Logistics (OPLOG), Division of
Graduate
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Hodge, D. J. "Problems of stochastic optimal control and yield management." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604120.
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We present a collection of results in the broad area of stochastic optimization. Our basic model is that of dynamic resource allocation via customer acceptance control. We begin by modelling optimal acceptance to a discrete-capacity service-on-demand system where customers arrive with differing demands and revenues. With strong restrictions on customer types we establish the optimal policy under general arrival processes. With weaker restrictions we establish monotonicity properties under stationary arrivals. We than look at a deterministic demand-curve approach to the same problem; resource allocation over time. We solve the problem of non-overlapping customer demands, for a number of different demand curves. Our main work concerns selling perishable goods via customer acceptance control. We look at the optimal boundary between accepting and declining customers of different types. Existing papers demonstrate this threshold but fail to observe its surprisingly linear nature. We study the problem of finding the best linear threshold and see that, as a heuristic, it performs very well. Our study of linear thresholds educes an interesting problem: sample-path analysis. The problem concerns the evolution of segments of the sample-path in inventory-time space with regions of different downward drift. We succeed in fully characterising the studied sample path segments, finding a remarkable dual use of an interesting identity. In the final chapters, we look at two further problems of stochastic optimization. The first is an innovative approach to modelling future demand, utilizing previous price requests. Using these dynamic demand estimations we demonstrate monotonicity properties of the optimal pricing policy. The second problem is the famous parking problem first introduced by Rényi in the fifties. We study a Markov chain queuing model for the availability of parking spaces. We derive the pay-offs from the class of very natural threshold policies, with respect to an ‘average distance from venue’ objective.
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Chi, Zhihang. "Airline yield management in a dynamic network environment." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11735.
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Zhou, Ning 1970. "Improving line yield at Fab17." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9214.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Also available online at the DSpace at MIT website.
Includes bibliographical references (leaf 77).
Fab 17 was a Digital Equipment Corporation semiconductor manufacturing and development facility. In June of 1998, Intel purchased Fab 17 from Digital. Intel shifted the focus to manufacturing and implemented many Intel operation policies. Intel sold equipment back to Digital and reorganized the manufacturing organization. As a result of Intel's initiatives and increasing demand for Fahl 7 products, Fab 17's profitability was improved. Despite improved profitability, Fab 17 was not meeting line yield performance goals. This thesis examines line yield excursions at Fab 17. Root causes are identified, and recommendations are made. The thesis first analyzes the line-yield loss data at Fahl 7 from a macro perspective. Inexperienced technicians and multitasking are found to be associated with most line yield incidents. The thesis then studies line yield excursions in high leverage functional areas in detail. Two major root causes are identified. First, in the reorganization, many technicians switched to new roles and had to be retrained. The training was rushed. Due to low level of automation, processing wafer at Fab 17 requires experience and proficiency. Fab 17's wafer starts increased in the first two quarters of 1999. Technicians had to rush to process the wafers. This resulted in high stress, which leads to high probability of line yield excursion. The inexperienced technicians are even more prone to line yield excursions under high stress. In addition, Fab 17 lacked a minimum staffing policy. Often an inappropriate number of technicians are present on the manufacturing floor. This necessitates multitasking, which creates higher stress and leads to higher probability of line yield excursions. The thesis recommends operations policies to address these issues and reports the actual implementation and some preliminary results.
by Ning Zhou.
S.M.
M.B.A.
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Xylander, Jadwiga K. "Kapazitätsmanagement bei Reiseveranstaltern : Entscheidungsmodelle zur Kontingentierung im Yield Management /." Wiesbaden : Dt. Univ.-Verl, 2003. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=010634880&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Humair, Salal. "Yield management for telecommunication networks : defining a new landscape." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8787.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2001.Includes bibliographical references (leaves 141-146).
Can airline Yield Management strategies be used to generate additional revenue from spare capacity in telecom networks? Pundits believe "yes", based on several analogies between the industries such as, for instance, perishable inventory and negligible marginal cost of usage. However, no one has yet described how, one of the chief difficulties being the vastly different nature of airlines products and telecom services. Motivated to show how Operations Research can play a role in structuring this area, we: (i) argue that telecom Yield Management should be based on 'innovative' services explicitly designed to use only spare capacity, (ii) propose, borrowing from airlines, a framework to simplify related decision modeling, and (iii) demonstrate both our argument and the framework by articulating several 'innovative' telecom services and modeling them to varying degrees of depth. This thesis focuses only on the decision-making that will be required within a large infrastructure for operating new 'Yield Management' services. For each service, several decision variables can be considered to maximize revenue from available capacity, e.g. pricing, capacity limits and admission control, among others. Incorporating all such decisions in a single model usually leads to complicated formulations. A framework that decouples the decisions from each other to obtain simpler, more insightful models is therefore immensely helpful. We propose using the airlines modeling framework to separate the decisions involved in the operation of each new service. This framework classifies models into forecasting, over-booking, seat-inventory control, pricing and market segmentation to reduce the complexity of the system-wide problem. To make this framework useful for telecom, we provide a detailed interpretation of each category in the telecom context. . Finally, the majority of this thesis is the six service ideas that illustrate our argument and the models that demonstrate how the framework might be used. For each service we propose, we discuss possible markets and practical issues. We then formulate a model for one of the decisions resulting from the framework. These models are analyzed to varying depths to demonstrate the operating rules one can discover for revenue maximization. The contributions of this work are at multiple levels. In addition to our argument and examples of services proposed for telecom Yield Management, it structures the modeling questions in a coherent manner, exploiting more than only the high-level connections between airlines and telecom. Finally, the models themselves are useful and their contributions are at the analytical level. This thesis makes clear several connections between airline and telecom Yield Management that people have found difficult to establish in the past.
by Salal Humair.
Ph.D.
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VISWANATHAN, BALAJI. "YIELD MANAGEMENT IN THE HEALTHCARE INDUSTRY: A CASE STUDY." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin972936713.
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Hanušová, Karolína. "Yield (revenue) management a jeho uplatňování v hotelovém průmyslu." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-12465.
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Tourism trade as well as hotel industry plays an important role in the services sector of the national economy of many countries, including the Czech Republic. The success of the whole branch is significantly influenced by demand fluctuations which usually occur in seasonal terms. Nowadays, however, when the world economy is afflicted by economical crisis, the demand downturns are apparent even in the times of high season. That is why the companies search for methods which would help to soften the impact of the crisis. Yield management appeared in hotel industry more than 20 years ago and is now used in many hotel chains and even small independent hotels. Its goal is to eliminate the demand fluctuation through an effective use of the hotel capacity. In practice it means to ensure that the right rooms are sold to the right customer for the right price. The aim of this thesis is a presentation of an application of Yield management theory in practice, in case of Hilton Prague hotel and to find out the opportunities of the Yield management to reduce the impact of economical crisis. First, we will need to define the base and principals of Yield management. Then we will apply them in practice to the Hilton Prague hotel. Finally, for the use of this hotel, we will examine the methods of smoothing the stroke of the crises.
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Pokorná, Martina. "Yield management a jeho uplatnění ve službách cestovního ruchu." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-161812.
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Tato práce shrnuje dosavadní teoretické poznatky o yield managementu a na jejich základě analyzuje jeho postavení mezi podniky cestovního ruchu v České republice i ve světě. Část práce, která se zaměřuje na Českou republiku, podrobněji hodnotí znalost a využití yield managementu zejména v oblasti hotelnictví. K tomuto vyhodnocení slouží především provedené dotazníkové šetření, které mapuje všeobecné povědomí o yield managementu a zjišťuje do jaké míry jsou jeho nástroje využívány mezi českými hotely.
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Qi, Hao Howard. "Personal taxes, default, liquidity and risky bond yield spread." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2005. http://wwwlib.umi.com/cr/syr/main.
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Salmins, Sandra S. (Sandra Sylvia). "Apple tree growth and yield in alternative ground management systems." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68256.
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Dwarf apple tree growth and yield under several non-herbicidal ground management systems were compared. Six ground cover systems were established in two newly planted orchards. After two growing seasons, trees in the straw mulch and geotextile mulch treatments had larger trunk cross-sectional areas and more shoot growth than trees in the red fescue and insectary plant cover treatments. Growth of trees under the manure mulch and cultivation treatments was intermediate. When four of the systems were established along rows of five-year old trees in an existing orchard, the increase in trunk cross-sectional area over two growing seasons was greatest for trees in the manure mulch and straw mulch followed by tose in geotextile mulch, trees in the red fescue grew least. The use of a mulch, such as straw or geotextile, has a favourable effect on growth and has potential for use in organic orchards.
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MORAIS, LUIZ GUSTAVO ALCURE DE. "YIELD MANAGEMENT IN RIO DE JANEIRO HOTELS: SURVEY AND ANALYSIS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3329@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOComo conseqüência da desregulamentação da indústria aérea americana nos anos 70, Yield Management YM foi criado como uma ferramenta gerencial para maximizar os lucros e manter as vantagens competitivas de empresas do setor. Com o tempo, essa ferramenta passou a ser utilizada por diversas empresas prestadoras de serviço, quando existe uma demanda variável para uma capacidade fixa e elevado custo de ociosidade, ajudando os gerentes a maximizar as receitas das suas operações. Basicamente, YM é o processo de alocação do tipo certo de capacidade, para cada tipo de cliente, ao preço certo, para que se maximizem os lucros. Pode-se ainda dizer que YM é uma forma sistemática de realizar um tipo de preço discriminatório em função de dados de demanda, de ocupação e dos custos marginais de utilização do recurso (avião, hotel, ou outro sistema prestador de serviço). Esta dissertação tem como objetivo verificar como os maiores hotéis turísticos do Rio de Janeiro se utilizam desta ferramenta em suas operações de reservas e vendas. Para atingir tal objetivo, selecionou-se uma amostra de onze hotéis na orla marítima. Entrevistas foram realizadas com os respectivos gerentes responsáveis pelo processo de reservas e/ou vendas, que responderam a um sobre a atual aplicação dos elementos de YM dentro da organização. Os resultados indicaram que o uso de YM é ainda muito pouco difundido entre esses hotéis, sendo reconhecido e de aplicação incipiente apenas em hotéis de maior porte pertencentes a cadeias, sobretudo internacionais. Alguns impedimentos indicados pelos respondentes e inferidos de suas respostas são comentados.
As a consequence of the deregulation of the American airline industry in the 70 s, Yield Management was created as a managerial tool in order to maximize the profits and to keep the competitive advantages of companies of the sector. With time, this tool was adopted by other service companies, where a flexible demand for a fixed capacity and high under utilization costs exist, helping the managers to maximize their operations revenues. Yield Management (YM), or Revenue Management, is the allocation process of the right type of capacity to each type of customer at the proper price to maximize the sales revenues of services, or of highly perishable goods. It can still be said that YM is a systematic form to carry out a type of discriminatory price to meet demand taking into account occupation data and the marginal cost of resource utilization (airplane, hotel, or another service rendering system). The study presented in this thesis aimed at verifying how the main tourist hotels of Rio de Janeiro are taking advantages of this tool within their reservation and sales processes. To accomplish this objective, a sample of eleven hotels was selected amongst the fifteen more important hotels of the main touristic area of Rio de Janeiro City. Interviews were carried out with the managers responsible for the reservation and, or sales, departament, who answered a questionnaire about the current application of YM elements within the organization. The results have indicated that YM is still very little spread out among these hotels, being recognized and of incipient application, only in large hotel chains, mainly, the international ones. Some obstacles pointed out by the respondents and inferred from their responses are commented.
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Silvertooth, J. C., and E. R. Norton. "Evaluation of Irrigation Termination Management on Yield of Upland Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/210969.
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A single field study was conducted in 1996 at the Maricopa Agricultural Center (1,175ft. elevation) to evaluate the effects of two dates of irrigation termination on the yield of a common Upland cotton variety (DPL 5415). Planting date was 11 April (667 HU/Jan 1 86/55° F thresholds. Two dates of irrigation termination (IT1 - IT2) were imposed based upon crop development into cut-out, with IT1 (14 August) being provided such that bolls set at the end of the first fruiting cycle would not be water stressed and could be fully matured The second termination (IT2) date was 10 September, which was staged so that soil moisture would be sufficient for development of bolls set up through the first week of September. Lint yield results revealed no differences between IT1 and IT2.
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Chvojka, Erik, and David Lovén. "Dividend yield strategies in Sweden." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354811.
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Griffin, Robert K. "Critical success factors of lodging yield management systems : an empirical study /." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07102007-142522/.
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Reinholtz, Amanda, and Amanda Reinholtz. "Reforestation, Water Yield, and Management of Micro-Watersheds in Central America." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12531.
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In Central America, two conflicting narratives are used to describe the relationship between forest cover and water availability, with implications for management of water resources throughout the region. Many resource managers believe forests increase dry season water availability, but scientific consensus refutes this perspective. This study analyzes the narratives explaining the relationship between forest cover and dry season water yields in Central America and how they influence resource management. In a case study of the Sasle catchment in Nicaragua, I use a combination of satellite imagery analysis and SWAT hydrologic modeling to investigate land use change over the past 25 years and the potential impact of these changes on the hydrology of the catchment. False perceptions of the role of land cover in hydrology are influencing management practices in sensitive headwater catchments and creating unintended results. A broader perspective on the socio-political and scientific context of these narratives is needed.
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Qaddoum, Kefaya. "Intelligent real-time decision support systems for tomato yield prediction management." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/58333/.
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This thesis describes the research and development of a decision support system for tomato yield prediction. Greenhouse horticulture such as tomato growing offers an interesting test bed for comparing and refining different predictive modelling techniques. The ability to accurately predict future yields, even for as little as days ahead has considerable commercial value to growers. There are several (measurable) causal variables. Some such as temperature are under the grower's control, while others are not. Modern predictive techniques, based on data mining and self-calibrating models, may be able to forecast future yields per unit area of greenhouse better than the biological causal models implicitly now used by growers. Over the past few decades, it has been possible to use the recorded daily environmental conditions in a greenhouse to predict future crop yields. Existing models fail to accurately predict the weekly fluctuations of yield, yet predicting future yields is becoming desperately required especially with weather change. This research project used data collected during seasonal tomato life cycle to develop a decision support system that would assist growers to adjust crops to meet demand, and to alter marketing strategies. The three main objectives are: firstly, to research and utilize intelligent systems techniques for analysing greenhouse environmental variables to identify the variable or variables that most effect yield fluctuations, and Secondly, to research the use of these techniques for predicting tomato yields and produce handy rules for growers to use in decision-making. Finally, to combine some existing techniques to form a hybrid technique that achieves lower prediction errors and more confident results. There are a range of intelligent systems (IS), which are used to process environment data, including artificial neural networks (ANNs), genetic algorithms (GA) and fuzzy logic (FL). A model providing more accurate yield prediction was developed and tested using industrial data from growers. The author develops and investigates the application of an intelligent decision support system for yield management, and to provide an improved prediction model using intelligent systems (IS). Using real-world data, the intelligent system employs a combination of FL, NN and GA. The thesis presents a modified hybrid adaptive neural network with revised adaptive error smoothing, which is based on genetic algorithm to build a learning system for complex problem solving in yield prediction. This system can closely predict weekly yield values of a tomato crop. The proposed learning system is constructed as an intelligent technique and then further optimized. The method is evaluated using real-world data. The results show comparatively good accuracy.Use was made of existing algorithms, such as self-organizing maps (SOMs), and principal component analysis (PCA), to analyse our datasets and identify the critical input variables. The primary conclusion from this thesis is that intelligent systems, such as artificial neural networks, genetic algorithm, and fuzzy inference systems, can be successfully applied to the creation of tomato yield predictions, these predictions were better and hence support growers’ decisions. All of these techniques are benchmarked against published existing models, such as GNMM, and RBF.
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Mueller, Nathan D. "Improving corn and soybean yield through fertility and weed management practices." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/14844.
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Doctor of PhilosophyDepartment of Agronomy
Dorivar Ruiz Diaz
Winter annual weeds (WAW) could affect nitrogen supply for corn production. The objectives of first study were to determine the diversity and abundance of WAW and to evaluate the effect of delaying herbicide applications on nitrogen supply and no-till corn response. Research was conducted in 2010 and 2011 at 14 sites in eastern Kansas. A factorial arrangement of three herbicide application dates (Nov.-Mar., April, and May) and five N rates were used. The three most abundant WAW across sites were henbit, purslane speedwell, and horseweed. Delaying herbicide application until April significantly reduced early corn N uptake by 52 mg N plant-1, chlorophyll meter readings at silking by 3.4%, and grain yield by 0.48 Mg ha-1 across sites. An additional 16 to 17 kg N ha-1 was needed to maintain yield if herbicide application was delayed until April. Starter and foliar micronutrient fertilization can potentially increase corn and soybean yield. The objectives of the second study were to evaluate crop response from combinations of starter and foliar fertilizers that contain N-P-K mixtures with and without a blend of micronutrients at four sites for each crop under irrigated conditions. No early corn growth or yield increase was attributed to application of micronutrients (Fe, Mn, Zn, Cu, and B) beyond what was achieved with N-P-K starter fertilization. There was an increase in soybean height (8 cm) and yield (293 kg ha-1) with starter fertilizer containing N-P-K plus micronutrients over the control. No increase in corn or soybean yield was obtained with foliar fertilization. The objective of the third study was to compare soil mobility and changes in soybean nutrient concentration in the leaf and seed from Mn and Zn sources (EDTA and oxysulfate) at two sites. Zinc sources were more mobile in the soil. Both Zn sources increased seed Zn concentration. Manganese oxysulfate increased seed Mn concentration. However, soybean trifoliolate leaf and seed Mn concentration decreased with soil-applied Na2EDTA and MnEDTA. This response was attributed to formation of FeEDTA and increased Fe supply that reduced root Mn absorption. Manganese EDTA is not recommended for soil application.
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Wang, Guangyao (Sam), Mario Gutierrez, Michael J. Ottman, and Kelly Thorp. "Durum wheat yield prediction at flowering stage for late N management." College of Agriculture, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/203775.
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Managing late N application effectively in durum wheat is important to reach desirable protein content. Yield prediction at anathesis is needed to estimate N requirement for the crop and N application rate. In this project, we use canopy reflectance and image processing, measured at anthesis, to estimate yield at harvest. Our results of the growing season 2009-2010 suggested that the canopy reflectance index ‘NWI-4’ and the spike pixel size obtained from image processing at anthesis are potential approaches to predict durum wheat yield at harvest. The final goal of this research is to find a simple and rapid method to manage late N fertilizer to reach desirable grain protein content.
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Silvertooth, J. C., and E. R. Norton. "Evaluation of Irrigation Termination Management on Yield of Upland Cotton, 1995." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/210752.
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A single field study was conducted in 1995 at the Maricopa Agricultural Center (1100 ft. elevation) to evaluate the effects of three dates of irrigation termination on yield a common Upland cotton variety (DPL 5415). Planting date was 3 April (469 HU /Jan 1 86/55° F thresholds). Following difficult establishment, crop vigor was generally low all season, with a relatively strong level of fruit retention. Three dates of irrigation termination an -1T3) were imposed based upon crop development into cut -out, with IT1 (21 August) set such that bolls set at the end of the first fruiting cycle would not be water stressed and could be fully matured. The third termination (IT3) date was 22 September, which was staged so that soil moisture would be sufficient for development of bolls set up through the first week of September. The second irrigation termination (IT2, 1 September) was intermediate to IT1 and IT3. Lint yield results revealed a 139 lb. lint/acre difference between IT1 and IT3, which was statistically significant (P < 0.05).
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Brand, Howard James Jarrell. "Towards Autonomous Cotton Yield Monitoring." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/72908.
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One important parameter of interest in remote sensing to date is yield variability. Proper understanding of yield variability provides insight on the geo-positional dependences of field yields and insight on zone management strategies. Estimating cotton yield and observing cotton yield variability has proven to be a challenging problem due to the complex fruiting behavior of cotton from reactions to environmental conditions. Current methods require expensive sensory equipment on large manned aircrafts and satellites. Other systems, such as cotton yield monitors, are often subject to error due to the collection of dust/trash on photo sensors. This study was aimed towards the development of a miniature unmanned aerial system that utilized a first-person view (FPV) color camera for measuring cotton yield variability. Outcomes of the study led to the development of a method for estimating cotton yield variability from images of experimental cotton plot field taken at harvest time in 2014. These plots were treated with nitrogen fertilizer at five different rates to insure variations in cotton yield across the field. The cotton yield estimates were based on the cotton unit coverage (CUC) observed as the cotton boll image signal density. The cotton boll signals were extracted via their diffusion potential in the image intensity space. This was robust to gradients in illumination caused by cloud coverage as well as fruiting positions in the field. These estimates were provided at a much higher spatial resolution (9.0 cm2) at comparable correlations (R2=0.74) with current expensive systems. This method could prove useful for the development of low cost automated systems for cotton yield estimation as well as yield estimation systems for other crops.Master of Science
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Frogbrook, Zoe Louise. "Geostatistics as an aid to soil management for precision agriculture." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314311.
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Reis, Amy Lynne. "A study of the performance of high yield bond funds." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/37698.
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Semrádová, Michaela. "Možnosti a bariéry uplatňování yield managementu ve vybraném hotelu." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-162517.
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This thesis deals with the theory of yield management as an effective method of achieving business goals, presenting its application on a particular accommodation facility. As a result of analyzing the existing yield management techniques used in the facility, further solutions are proposed to increase its revenue by means of using yield management techniques of differential pricing, overbooking and demand segmentation.
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Norton, E. R., and J. C. Silvertooth. "Development of a Yield Projection Technique for Arizona Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/197473.
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A series of boll measurements were taken at numerous locations in cotton producing areas across Arizona in 1999 in an attempt to continue to develop a yield prediction model with a project that began in 1993. Results from 1995 showed the strongest relationship between final open boll counts and yield compared to a number of other measurements. Based on these results, data collection on boll counts began in 1996 and has continued in 1997, 1998, and 1999. Boll counts were taken as the number of harvestable bolls per meter. All boll count measurements were made within one week of harvest. Number of bolls per unit area were then correlated to lint yield and an estimate for the number of bolls per area needed to produce a bale of lint was calculated. Estimates using all four years of data combined indicate that approximately 38 bolls per meter are needed to produce one bale of lint per acre.
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Husman, S. H., and J. C. Silvertooth. "Plant Population Effects on Pima S-6 Lint Yield." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/208640.
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A replicated field study was conducted at the Maricopa Agricultural Center in 1991 to investigate the effect of plant population density on Pima S-6 lint yield. Treatments ranged from a low of 10,465 plants per acre to a high of 65,000 plants per acre. There were no significant yield differences observed with populations between 17,000 plants per acre and 65,000 plants per acre. Significant yield decreases occurred when populations were reduced below 17,000 plants per acre.
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Norton, E. R., and J. C. Silvertooth. "Development of a Yield Projection Technique for Arizona Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/210756.
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A series of boll measurements were taken at several locations across the state in 1995 in an attempt to develop a yield prediction model. Measurements were taken out of two strip plot variety trials at the University of Arizona Maricopa Agricultural Center and in the Coolidge area, and also out of two commercial fields in Buckeye and Paloma Ranch over a period of approximately 2 months from peak bloom through cut-out. Data analysis revealed a best fit model that included seedcotton yield as a function of boll count, boll size, boll diameter, and heat units accumulated after planting (HUAP). A series of open boll counts were also taken from over 120 experimental units across the state within one week of harvest. The data revealed strongest relationships between final open boll counts and yield.
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Günther, Dirk. "Airline yield management : optimal bid prices, Markov decision processes and routing considerations." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/30680.
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Kristanto, Paulus. "Analysis of price competition with yield management in the US Airline industry." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/30705.
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Skwarek, Daniel Kew. "Competitive impacts of yield management system components : forecasting and sell-up models." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10172.
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Kerns, David L., and Glenn C. Wright. "Pest Management and Yield Enhancement Qualities of Particle Film Technologies in Citrus." College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/223673.
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Surround WP and Snow were evaluated for their ability to manage citrus thrips populations in lemons on the Yuma Mesa, and their impact on lemon yield, fruit quality, and packout. Both Surround and Snow effectively controlled citrus thrips and prevented fruit scarring, but their ability to manage Yuma spider mite was inconclusive. Preference tests indicated that both Surround and Snow act primarily by repelling the thrips, but also induce some mortality. Surround produced higher yields than Snow at the first harvest (#8 ring), but did not differ from the commercial standard. There were no differences in yield among treatments for the strip harvest, nor were their any differences in total yield. These data suggest that Surround may have some yield or increased fruit earliness enhancement qualities and that Snow may be slightly detrimental. There were no statistical differences among any of the treatments in fruit size frequency or quality for any of the harvests, and there was no apparent benefit from applying an additional application of Surround or Snow post thrips season solely for quality, fruit size, or yield enhancement.
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Mehos, Stephen C. (Stephen Charles). "High yield bond new issues used to finance acquisitions during 1993." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/12088.
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McWilliam, Simon Charles. "Plant establishment, canopy structure and yield formation in oilseed rape." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243684.
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Silvertooth, J. C., A. Galadima, and R. Tronstad. "Irrigation Termination Effects on Cotton Yield and Fiber Quality." College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/198213.
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Field experiments were conducted in 2004 and 2005 at the University of Arizona Maricopa Agricultural Center (1,175ft. elevation) to evaluate the effects of five irrigation termination (IT1, IT2, IT3, IT4, and IT5) dates on yield and fiber micronaire of eleven Upland cotton varieties and one Pima variety. In addition, the economic relationships of IT treatments were also evaluated. The experimental design was a split plot in a randomized complete block design with three replications. The main treatments included the five IT dates and the subunits consisted of 11 Upland varieties and a Pima variety. The first two IT treatments (IT1 and IT2) were imposed with the intention of terminating irrigations very early and pre-maturely at peak bloom. Based upon current UA recommendations for IT to complete a single cycle fruit set, the more optimal date of IT would have included one or two additional irrigations (beyond IT1 and IT2). In this experiment, IT2 was structured to provide an additional (one) irrigation just past peak bloom. For the IT3 plots, the intention was to attempt to time termination in advance of cutout. The 2004 and 2005 IT4 and IT5 were imposed to attempt to complete the primary fruiting cycle development and produce a second cycle fruit set that require irrigations until late August and late September, respectively. In general, lint yield and micronaire results revealed significant differences among the IT treatments and varieties. In a similar fashion to a previous set of IT experiments (2000-2002), lint yield and micronaire values consistently increased with later IT dates. The best combined lint yield and micronaire results were achieved with IT4 date, which received 12 and 18 in. less irrigation water than IT5 in 2004 and 2005, respectively. In 2004 and 2005, the 12 and 18 in. water saved equate to approximately 20% and 30% less water used under the conventional practice, respectively. The average marginal value of water for all eleven Upland varieties in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 for November 2004 prices and low carrying costs is calculated at $320.07, $150.15, $100.54, and -$28.16 per acre-foot of water. If steeper mike discounts (November 1999), a lower base lint price (45¢/lb.), and higher costs (i.e., more costly insecticide and chemical costs) are imputed to extend the crop, the marginal value of an acre-foot of water for all Upland varieties and replications in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 is estimated at $164.04, $48.15, $12.97, and -$94.79. Profitability and the value of water for extending the season varies quite markedly between different varieties and termination dates.
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Opole, Rachel Adoyo. "Effect of environmental stress and management on grain and biomass yield of finger millet (Eleusine coracana (L.) Gaertn.)." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13964.
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Doctor of PhilosophyDepartment of Agronomy
P.V. Vara Prasad
Productivity of grain crops is highly sensitive to changing climates and crop management practices. Response of finger millet [Eleusine coracana (L.) Gaertn.] to high temperature stress, and intensive management practices such as increased seeding rates and fertilizer application are not clearly understood. The objectives of this research were to determine the effects of (a) season-long, and short episodes of high temperature stress on growth and yield traits of finger millet, (b) seeding rates and nitrogen fertilizer application rates on grain and biomass yield, and (c) to evaluate the finger millet minicore collection for high grain and biomass yield. Controlled environment studies were conducted to determine the effects of high temperature stress on physiological, growth and yield traits. Field studies were conducted in Manhattan and Hays (Kansas) and Alupe (Kenya) to determine the effects of seeding and nitrogen fertilizer rates on growth and yield traits. Finger millet minicore collection was evaluated under field conditions in India, for phenology, growth and yield traits. Season long high temperature stress of 36/26 or 38/28°C compared to 32/22°C decreased panicle emergence, number of seeds per panicle, grain yield and harvest index. Finger millet was most sensitive to short episodes (10 d) of high temperature (40/30°C) during booting, panicle emergence and flowering stages, resulting in lower number of seeds, and grain yield. Finger millet responded to the interaction between environmental (locations) and temporal (years) factors. In general, locations with higher rainfall had greater grain and biomass yield than those with low rainfall. There was no influence of seeding rates (3.2 or 6.0 kg ha[superscript]-1) at Hays and Alupe. However, in one of the two years in Manhattan, higher seeding rate of 6.0 kg ha[superscript]-1 increased grain yield compared to 3.2 kg ha[superscript]-1. There was no influence of nitrogen rates (0, 30, 60 or 90 kg ha[superscript]-1) on grain or biomass yield at all three locations. However, higher fertilizer rates had greater percentage lodging. The finger millet minicore collection displayed large ranges for most quantitative traits including days to flowering, plant height, number of fingers panicle[superscript]-1, grain yield, biomass yield, and lodging; and had >60% heritability. Some of the genotypes from the minicore collection have the potential to increase grain and biomass yield and abiotic stress tolerance of finger millet.
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Metcalfe, Todd Andrew. "Modeling Farm-Level Costs of the Yield Reserve Program." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/44252.
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Nonpoint Source (NPS) pollution, pollution that comes from diffuse sources that are difficult to trace back to a single point such as farm fields, is a major concern affecting America's water ways. Nationally, agriculture is the leading source of water impairment and has also been identified as the largest source of pollution affecting the Chesapeake Bay.
There are proposals now for a program that would pay farmers to use 15 percent less than the extension recommended amount of fertilizer. Known as the Yield Reserve Program, or Enhanced Nutrient Management, this policy could possibly help to reduce the nutrient loads.
The objective of this study was to evaluate the effects of a Yield Reserve Program on farm yields and net revenues. Costs were estimated for different policy implementations for the Virginia Coastal Plain to better understand problems with this type of program. The effects of Yield Reserve on enterprise net returns, yields, and N applications for corn under varying weather and soil conditions were estimated.
Based on experimental trials from North Carolina and Virginia from 2000 to 2004, yield response functions were calculated for corn. The costs of the Yield Reserve Program vary depending on its implementation, but under current proposals these costs were estimated at $113 per hectare, and $10,855,000 for the coastal plain. This proposal is a more costly program than would be necessary to compensate farmers for yield losses based on estimates in this study.Master of Science
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Farr, Charles. "Lint Yield of Planting Pima S-6 at Three Dates." College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/204534.
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Ogola, J. B. Ochanda. "Improving water use efficiency of maize through proper nitrogen management." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340024.
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Cox, Graeme J. "A yield mapping system for sugar cane chopper harvesters." University of Southern Queensland, Faculty of Engineering and Surveying, 2002. http://eprints.usq.edu.au/archive/00004617/.
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[Abstract]: Yield maps provide essential information for the spatial analysis and evaluation of crop production management at a within field level. Technology has been developed to conduct yield mapping in various crops including grain, potatoes and forage, but as yet no technology exists for yield mapping sugar cane. The chopper harvester is the most common form ofmechanical harvester for sugar cane. Therefore, the goal of this research is to develop a yield mapping system for the chopper type sugar cane harvester.After a review, it is proposed that a suitable accuracy goal for the sugar cane mass flow sensor would be ‘less than 5% cumulative measurement error, 95% of the time (2 standard deviations), measured over a 100m2 harvest area’.Existing mass flow sensors for other crops are reviewed.Based on this review four potential techniques are proposed to measure the mass flow rate of sugar cane. These were defined as the chopper power, elevator power and feed roller separation and weigh pad. These weretested simultaneously by placing various sensors on a single harvester and comparing the sensor outputs with the mass flow rate as measured by a weigh truck. In this trial, all techniques offered potential but none produced results close to the accuracy goal. A weighing technique, known as the ‘weigh pad’, offered the most potential for improvement and potential to accurately measure the mass flow rate with a single calibration under all conditions. The weigh pad technique suffered from very small load cell sensitivity to flow rate, drift in baseline readings and susceptibility to mechanical noise/acceleration dynamics.An opportunity arose to install a complete yield mapping system on a harvester within a commercial operation. This opportunity was accepted to assess the potential for applying yield maps to the agronomic management of sugar cane. Because the weigh pad sensor required further development at this stage, chopper and elevator power were used as a measure of mass flow rate. A full yield mapping system was developed. Yield mapping, directed soil sampling and variable rate gypsum application was conducted on a case study field. Economic analysis shows a clear economic benefit when compared with standardmanagement.Analysis is conducted on the weigh pad sensor examining its susceptibility to mechanical noise/acceleration dynamics. Theory is developed to mathematically model the effects of acceleration dynamics on the accuracy of weigh pad sensor. Laboratory bench testing supported the mathematical model. From the theoretical and experimental analysis a number of conclusions are drawn:· The weigh pad should be made as light as possible to minimise the error due todynamic conditions.· Electronic analogue filters should be used to reduce the noise due to externalacceleration.· The weigh pad should be as rigid as possible to maximise its natural frequency.A new weigh pad sensor was designed based on these conclusions. Field trials indicated the effects of external accelerations dynamics were significantly reduced. Baseline drift was then found as the next major factor limiting accuracy. The baseline drift was principally caused by the secondary extractor fan of the harvester inducing a negative pressure on the weighpad. A rubber curtain placed between the weigh pad and the secondary extractor fan reduced the negative force on the weigh pad due to the secondary extractor fan by 74% (from 17 N to 4.4 N). Therefore it is recommended the curtain be used to minimise the impact of the secondary extractor fan on the baseline drift of the weigh pad.A yield mapping system has been developed for the sugar cane chopper harvester incorporating the weigh pad sensor, a ground speed sensor, a DGPS receiver, a yielddisplay/monitor and data logger. Three identical systems have been constructed and installed on three harvesters for the 1998 cane harvest season. The results show sugar cane could be yield mapped using standard yield mapping principles.The level of accuracy being achieved by the yield mapping system is less than 16% error, with 95% confidence, over a measurement area of approximately 1400 m2. Although theaccuracy achieved is not to the desired research goal, yield maps were produced with satisfactory detail to make agronomic management decisions. The reliability of the sugar cane yield mapping system under field condition in a commercial operation was satisfactory. However, two techniques are proposed (“auto-zeroing” and “batch weighing” techniques) to improve the accuracy and reliability of the weigh pad readings during wet or adverseharvesting conditions.After note: At the time of writing the NCEA along with Case Austoft (CNH) were continuing to conduct research and development on the system and are intending to make theyield mapping system available as a standard item on new harvesters and a retrofit unit on existing harvesters in the near future (C. Barret, per. comm. 2001). The proposed “autozeroing” and “batch weighing” techniques are being tested.
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Lindenmeier, Jörg. "Yield-Management und Kundenzufriedenheit : konzeptionelle Aspekte und empirische Analyse am Beispiel von Fluggesellschaften /." Wiesbaden : Dt. Univ.-Verl, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013052273&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Hwang, Jung Yoon. "Spatial stochastic processes for yield and reliability management with applications to nano electronics." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1500.
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This study uses the spatial features of defects on the wafers to examine the
detection and control of process variation in semiconductor fabrication. It applies
spatial stochastic process to semiconductor yield modeling and the extrinsic reliabil-
ity estimation model. New yield models of integrated circuits based on the spatial
point process are established. The defect density which varies according to location
on the wafer is modeled by the spatial nonhomogeneous Poisson process. And, in
order to capture the variations in defect patterns between wafers, a random coeff-
cient model and model-based clustering are applied. Model-based clustering is also
applied to the fabrication process control for detecting these defect clusters that are
generated by assignable causes. An extrinsic reliability model using defect data and
a statistical defect growth model are developed based on the new yield model.
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Deryng, Delphine. "Simulating the effects of climate and land management practices on global crop yield." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=92347.
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Global warming resulting from increasing greenhouse gas emissions is a threat to global food production. A rise in temperatures along with a shift in precipitation regimes is expected to decrease production in the future. However, farm management, such as the choice of crop cultivar, planting decisions, and irrigation can help farmers to alleviate some of the potential crop yield losses from climate change. In order to estimate the role of climate and agricultural management practices on yield, a new global crop model, PEGASUS 1.0 (Predicting Ecosystem Goods And Services Using Scenarios) has been developed for maize, soybean, and spring wheat. This thesis presents the methods used to develop the model, and its evaluation against present-day data, along with a model sensitivity experiment to a global warming of 2°C. Overall, results for present-day simulations are reasonable. Simulated planting and harvesting dates occur within the range of observations for more than 62% of total crop harvested areas, for each of the three crops. A comparison between simulated and observed crop yields indicates a weighted coefficient of determination, with the weighting based on crop harvested area, of 0.81 for maize, 0.63 for soybean, and 0.45 for spring wheat. The model simulates that an increase in temperature will result in a global decrease in crop yields. Nevertheless, adapting planting dates and cultivar choices to changes in temperature can avoid 6078% of yield losses globally. Overall, the model results suggest that agricultural production in the richest countries, mostly located in the northern high latitudes, could benefit from increase in temperature, while the agriculture in the poorest countries in the tropics are likely to suffer the most.Le réchauffement planétaire lié à l'émission croissante des gaz à effet de serre menace la production alimentaire mondiale. Une augmentation des températures ainsi qu'une modification des régimes de précipitations augmentent les risques de mauvaises récoltes à long terme. Toutefois, certaines pratiques agricoles, comme le choix du type de semence, les dates de semis, et l'irrigation permettent aux agriculteurs de s'adapter au mieux aux variations climatiques. Afin d'évaluer le rôle combiné du climat et des pratiques agricoles sur le rendement des cultures, un nouveau modèle agricole, PEGASUS 1.0 (Predicting Ecosystem Goods And Services Using Scenarios), a été développé. PEGASUS simule le rendement du maïs, du soja, et du blé de printemps à l'échelle mondiale. Cette thèse présente les méthodes utilisées pour développer le modèle, ainsi que son évaluation sur les données agricoles actuelles. Par ailleurs, la sensibilité du modèle à un réchauffement global de 2°C a été estimée. De manière générale, les résultats des simulations correspondant aux conditions climatiques actuelles sont satisfaisants. Ainsi, les dates de semence et de récolte simulées coïncident avec l'éventail des dates observées pour plus de 62% des surfaces cultivées, pour chacune des trois cultures. De plus, l'évaluation du rendement agricole calculé indique un coefficient de détermination, pondéré par la surface récoltée, égale à 0.81 pour le maïs, 0.63 pour le so ja, et 0.45 pour le blé de printemps. Les résultats des simulations correspondant à un réchauffement de la température montrent une réduction générale des rendements agricoles. Cependant, lorsque les dates de plantation et le choix du cultivar sont adaptés à la nouvelle température, les pertes sont réduites de 60 à 78%. Les variations de rendement agricoles ont été comparées par revenus économiques, démontrant que les pays les plus riches pourraient bénéficier$