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1
Granados, Juan D. "Complexity yields to simplicity." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1314207325.
Testo completo
2
Widodo. "The Effects of Spacings & Cultivars on Biological Yields, Yields, Component of Yield & Harvest Index of Green Bush Snap Bean (Phaseolus vulgaris L.)." TopSCHOLAR®, 1989. https://digitalcommons.wku.edu/theses/2967.
Testo completoAbstract (sommario):
The effects of cultivars and plant spacings on biological yield, seed yield, seeds per pod, average seed weight, and harvest index of beans (Phaseolus vulgaris L.) were studied in 1987 and 1988. Two cultivars, 'Blue Lake 27' and 'Kentucky Wonder 125' and four plant spacings -- 7, 14, 21, and 28 cm, constituted eight treatments that were arranged in a split-plot with four replications. Each experimental unit or hill consisted of five plants -- four in the corners and one in the center of a square. Spacings treatment were established by varying the distance between the center plant and the four corner plants. Corner plants provided competition; only the center plant was harvested for experimental data. The data were subjected to analysis of variance procedure for a split-plot design, assuming a fixed model.
The cultivars had similar biological yield curves during the 1987 growing season and did not differ significantly for biological yield at the final harvest either year. Kentucky Wonder 125 produced significantly higher average seed weight and harvest index, but fewer seeds per pod, than did Blue Lake 274. In 1987, seed yield per plant was higher for Blue Lake 274 than for Kentucky Wonder 125; however, the cultivars did not differ significantly for seed yield per plant in 1988.
Spacing treatment effects were not significant when expressed through seed yield per plant, seeds per pod, average seed weight, or harvest index. Spacings affected biological yield significantly in 1988, but not in 1987. The linear response of biological yield to spacing was positive and significant both years. The linear effect of spacings on pod yield was significant in 1988, but not in 1987.
Drought conditions in 1987 and 1988 adversely affected bean growth and seed production. The experimental error, as evidenced by large coefficients of variation for treatment means, was unusually high. Consequently, some true cultivar and spacing effects may not have been detected.
3
Graham, Allan Wayne. "Environmental Liabilities and Bond Yields." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/28937.
Testo completoAbstract (sommario):
Environmental remediation liabilities are generated primarily as a result of past actions by a firm. The most important of these liabilities for domestic U.S. firms are related to Superfund sites as designated by the Environmental Protection Agency (EPA). These liabilities are important for domestic firms because of their size, which is estimated to be approximately $300 billion (Congressional Budget Office 1994) and because of public concern for the environment.
This study examines the relation among bond ratings, bond yields, and EPA-based estimates of contingent environmental remediation liabilities to test if the relationships hold as theory implies it would. Extant theory suggests that financial variables, such as environmental remediation liabilities, have incremental explanatory power beyond the information included in bond ratings for bond yield. The purpose of this study is to determine the importance of external estimates of a firm's contingent environmental liabilities for a firm's cost of debt. In addition, the manner in which a firm's contingent environmental liabilities are included in the costs of debt is examined in this study.
The results of this study indicate that external estimates for environmental liabilities are associated with the bond ratings and bond yield for a data set of new bond issues collected from the period 1995 to 1997. Despite that firms are increasing their recognition of environmental liabilities, either due to regulatory pressure or other factors, the measures based on EPA data still have significant explanatory power. The results imply that firms are either still lagging in appropriate recognition or that the external measures proxy for amounts imputed by the capital markets for some probable unspecified future costs. The latter explanation is supported by additional evidence in this study that the largest monetary measure of the liability is the most significantly associated with bond ratings and bond yields. Further, the results indicate that the external estimates are incorporated in bond ratings as part of the firm's default risk and have no direct influence over bond yield beyond that included in the bond ratings. This implies that bond ratings are particularly important for any evaluation of investment in debt securities from firms that have contingent environmental liabilities.<br>Ph. D.
4
Cook, Rebecca. "Chance Meeting Yields Research Bonanza." College of Agriculture, University of Arizona (Tucson, AZ), 1993. http://hdl.handle.net/10150/295741.
Testo completo
5
Badyal, Jasvinder Pal Singh. "Exotic options with stochastic dividend yields." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286311.
Testo completo
6
Shanks, Sarah M. "The Memory Yields: B.F.A. Thesis Exhibition." Ohio University Honors Tutorial College / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1401583720.
Testo completo
7
Gonçalves, Júlia Alves Roque. "Yield gap explaining factors and solutions to improve yields in a maize farm in Portugal." Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/21289.
Testo completoAbstract (sommario):
Mestrado em Engenharia Agronómica / Instituto Superior de Agronomia. Universidade de Lisboa<br>Over the decades, it has been found that agricultural intensification, that is, the increase in production per hectare, is substantially urgent and necessary, justified by the observed and expected population increase and the impossibility of agricultural expansion. One of the methods for achieving this goal is the study and investigation of yield gaps, which may be explained by unfavorable soil and climate conditions, or less adequate input management.
Given the socio-economic importance of maize crop in Portugal and the need for case studies that exemplify agricultural intensification methods, this dissertation aims to discover which are the reducing factors that justify the gap between the maximum and actual yields, known as yield gaps, which were analyzed between plots and years, and how large was the yield gap over the 10 years.
Through a database of irrigation appropriations, nitrogen applications, sowing dates and climate data, collected over 10 years and provided by Milho Amarelo company, located in the Santarem region, other variables were calculated, such as degree-day accumulation, cultural evapotranspiration and intercepted radiation. These data were analyzed annually according to the whole cycle and according to different phenological phases (vegetative and reproductive).
Once all variables were obtained and organized, statistical methods of bivariate and multivariate analysis were performed. The magnitude of yield gap was calculated according to the Approach 2 indicated by FAO 41.
The results show that interaction of sowing dates with climatic conditions are in the nature of this deviation, with gap’s magnitude ranging from 5% to 20%, depending on the climatic conditions of the year<br>N/A
8
Sampson, Helen G. (Helen Grace). "Biomass and protein yields, N2-fixation and N transfer in annual forage legume-barley (Hordeum vulgare L.) cropping systems." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68257.
Testo completoAbstract (sommario):
In this study, six annual legumes and the perennial, red clover (Trifolium pratense L.) were monocropped (MC) and intercropped (IC) with barley in a field study with three N levels, 0, 30 and 60 kg N ha$ sp{-1}$. At O kg N ha$ sp{-1}$, N$ sb2$-fixation and N transfer were estimated by the $ sp{15}$N isotope dilution (ID) method. At 60 kg N ha$ sp{-1}$, a direct $ sp{15}$N labelling method was employed to study N transfer. The hypotheses were that the annual species would be more productive within one growing season than red clover, that increased N levels would increase herbage dry matter (DM) and crude protein (CP), that the proportion of N derived from N$ sb2$-fixation in IC-legumes would be higher than that of MC-legumes and that within intercrops there would be evidence of N transfer. In neither year was the total DM yield of red clover, MC or IC, less than the rest of the legumes. In 1991, the total DM yield of intercrops responded to 30 kg N ha$ sp{-1}$; in neither year did the estimated total CP yield of MC-legumes or intercrops respond to N levels. Only in 1992 was there evidence of N$ sb2$-fixation and the proportion of N derived from fixation by IC-legumes was 145% higher than that of MC-legumes. Only the $ sp{15}$N direct labelling method gave evidence of N transfer, to associated legume and barley plants in 1991, and to associated legume plants in 1992.
9
Smith, Matthew K. "Trend yields and the crop insurance program." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13748.
Testo completoAbstract (sommario):
Master of Agribusiness<br>Department of Agricultural Economics<br>Allen M. Featherstone<br>Multiple Peril Crop Insurance (MPCI) is a federally subsidized crop insurance program designed to mitigate risk for farmers across the United States. Many changes in technology and weather have increased yields in recent years. This has caused some to argue for the crop insurance program to consider yield trends when setting yields for the producer. This thesis evaluates alternative Actual Production History (APH) methods for corn to determine differences in the methods and the resulting APH.
The key issue to be evaluated is that a producer’s APH may not be reflective of their “yield goal.” The thesis examined how the APH can differ under alternative methods of calculating an APH. Some methods examined are currently used by the Risk Management Agency (RMA). Other methods are hypothetical alternatives. This study examines alternative methods on a national, county, and a farm level.
This thesis demonstrates that adjusting APHs for yield trends provides a higher APH than an un-trended APH. The 7 Year Olympic Trended APH provides the highest APH in most cases for all the methods examined. The RMA Un-trended APH proved to provide the least yield on average for all methods examined. This demonstrates the importance of adjusting for yield trends to factor in agricultural technology advancements over time.
10
Mitchell, Hal Lee. "Predicting Pallet Part Yields From Hardwood Cants." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/41288.
Testo completoAbstract (sommario):
Pallet cant quality directly impacts pallet part processing and material costs. By knowing the quality of the cants being processed, pallet manufacturers can predict costs to attain better value from their raw materials and more accurately price their pallets. The study objectives were 1) to develop a procedure for accurately predicting hardwood pallet part yield as a function of raw material geometry and grade, processing equipment, and pallet part geometry, 2) to develop a model for accurately predicting raw material costs for hardwood pallet parts as a function of yield, 3) to examine current pallet industry methods of determining hardwood cant quality, and 4) to develop and evaluate hardwood cant grading rules for use in the pallet industry.
Yield studies were necessary to accurately quantify the relationship between yield and cant quality. Thirty-one yield studies were conducted throughout the Eastern United States at pallet mills producing pallet parts from hardwood cants. 47, 258 board feet of hardwood cants were graded, and the usable pallet part yield and yield losses were determined for each grade.
Yield losses were separated into three components: kerf loss, dimension loss, and defect loss. Kerf and dimension losses are a function of raw material and part geometry and were calculated without regard to cant quality. Defect loss is dependant on cant quality and was calculated for each cant grade as a function of total yield, kerf loss, and dimension loss.
Mathematical models were developed from twenty-eight mill studies to predict each yield loss component as a function of cant dimensions, grade, and orientation, cutting bill parameters, pallet part dimensions, and kerf. Dimension and kerf losses were predicted geometrically. Regression analysis was used to predict defect loss. Results indicated that these models accurately predicted the total yield of usable pallet parts and pallet part material costs as a function of cant quality and price.
Results also indicated that the pallet industry's current method of counting the number of "bad" ends per cant bundle to determine cant quality is not adequate. The
effectiveness of the proposed cant grading rules was determined by grading cants and analyzing the cant grade distributions and corresponding pallet part yields. The grade rules produced statistically different quality divisions between grades. However, a more practical single cant grade based on the minimum quality for the proposed grade 2 rules is recommended.<br>Master of Science
11
Chu, Chang-chi, and Thomas J. Henneberry. "Cotton Yields: Nitrogen and Harvest Aid Effects." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/208638.
Testo completoAbstract (sommario):
The results of field studies with N rates from 0 to 336 kg/ha, in combination with two growth regulators, ethephon (Prep® ɑ-chloroethyl phosphonic acid, Rhone-Poulenc Ag Co., Research Triangle Parr NC) and thidiazuron (Dropp® N- phenyl -N' -1,2,3 -thiadiazol -5ylurea, Nor-Am Ag Prod. Inc., Naperville, IL). Results showed that sidedress applications of N (ammonium nitrate) to cotton did not influence the defoliation effects of ethephon and thidiazuron, or reduce number of immature green bolls at harvest. Under short-season conditions, sidedress N applications did not effect yields. Ethephon and thidiazuron at the rates tested did not affect cotton lint yields. Thidiazuron alone or in combination with ethephon resulted in high percentages of cotton defoliation.
12
Brown, Paul W. "Heat Stress and Cotton Yields in Arizona." College of Agriculture, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/211290.
Testo completoAbstract (sommario):
Yield of upland cotton was related to heat stress in Yuma, LaPaz, Maricopa, and Pinal Counties for the period 1987-1999. Heat stress during the primary fruiting cycle was assessed using heat stress units (HSU) which were derived from mean daily canopy temperatures computed using a canopy temperature model and local AZMET weather data. Mean lint yields were computed for years with low, intermediate and high levels of HSU. Yields in years with low levels of heat stress were always significantly greater than yields in years with high levels of heat stress. Differences in yield between high and low heat stress years ranged from 100 lb/a in Maricopa County to 254 lb/a in Yuma County and averaged 166 lb/a across all counties. Differences in yield between the low and intermediate stress years, and intermediate and high stress years averaged 86 and 80 lb/a, respectively across all counties; however, these differences were not always significant in individual counties.
13
Peterson, Shelley. "Spatial variability of soil nitrogen, crop yields and delta yield in relation to variable rate nitrogen fertilization." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ35922.pdf.
Testo completo
14
Chipungahelo, Grace Mwaijande Samuel. "Intercropping sweet potato (Ipomoea batatas L. Lam.) cowpea (Vigna unguiculata L. Walp) and pineapple (Ananas comosus L. Merr.) under coconut (Cocos nucifera L.) in Tanzania." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299624.
Testo completo
15
Williams, Scott Charles. "Absolute bremsstrahlung yields 53 keV electrons on gold /." Fort Worth, Tex. : Texas Christian University, 2007. http://etd.tcu.edu/etdfiles/available/etd-07022007-104158/unrestricted/williams.pdf.
Testo completo
16
Cook, David. "Pricing Bond Yields in the European Bond Market." Scholarship @ Claremont, 2010. http://scholarship.claremont.edu/cmc_theses/9.
Testo completoAbstract (sommario):
This paper analyzes macroeconomic factors and their effect on 2-year government bonds of 11 countries in the European Monetary Union. I specifically looked at how a simultaneous budget and trade surplus effect a country's bond yield spread relative to Germany's bond yield. My model showed that double surplus countries have a larger yield spread than countries that do not have a double surplus.
17
Ghassemi-Golezani, Kazem. "The effects of seed quality on cereal yields." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306481.
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18
Chan, Shirley. "Survey vs market expectations of Treasury bill yields." Thesis, City University London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269354.
Testo completo
19
Rautenbach, Jeremy Brian. "Improving production yields in bio-pharmaceutical filter media." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111937.
Testo completoAbstract (sommario):
Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, in conjunction with the Leaders for Global Operations Program at MIT, 2017.<br>Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, in conjunction with the Leaders for Global Operations Program at MIT, 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 89-91).<br>This thesis presents methods to identify sources of variation in rolled goods manufacturing by defining the critical input process parameters, and the application of statistical process control. Sources of variation are prioritized according to a process control hierarchy, and reduced or eliminated through iterative cycles of rapid experimentation. This work emphasizes the value of team work, breaking down the organizational barriers between departments, knowledge sharing and the importance of a scientific approach to problem solving. FilterCo manufactures and assembles filter media catering to the ultrafiltration market growing at ~12% over the next five years. In a high growth scenario, production yield variability presents on-time delivery complications while below target yields drive significant scrap value. As FilterCo seeks to improve product lead time for its customers, while reducing WIP inventory, it must seek to maximize OEE with respect to product yield, equipment performance and availability. The variation identification, reduction and process control methodologies presented in this thesis are demonstrated to advance the goal of reducing production yield variation. The impact of the work has been verified on three filter media grades and have shown ~40% reduction in production yield variation, and rolled throughput yield improvements of ~30%. These improvements on the three membrane grades alone have resulted in an annualized saving equivalent to 60% of the total 2015 scrapped membrane value.<br>by Jeremy Brian Rautenbach.<br>S.M.<br>M.B.A.
20
Gardner, B. R., and T. C. Tucker. "Effect of Phosphorus Fertilizer Application on Cotton Yields." College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204087.
Testo completo
21
Rein, B. K., G. W. Thacker, and W. E. Coates. "Energy Consumption and Yields for Cotton Tillage Systems." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/204818.
Testo completoAbstract (sommario):
The energy consumption of 2 alternative tillage systems for continuous cotton production in Arizona were compared to a conventional system. The tests were conducted at the University of Arizona Marana Agricultural Center. Results of the study in a Pima I clay loam soil showed the sundance treatment to have the lowest energy requirement of 39 Hp-hr /ac (73 kW-h/ha); the USM system had the second highest of 58 Hp-hr /ac (107 kW-h/ha). The conventional system required 67 Hp-hr /ac (124 kW- h/ha). Average yields for all 3 systems were not significantly different. A continuation of this study will be conducted to determine long-term effects on energy consumption, yields, and soil compaction.
22
Husman, Stephen H. "Side-dress Temik® Effects on Lint Yields." College of Agriculture, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/210391.
Testo completoAbstract (sommario):
Temik 15G was side-dressed at a rate of 7 lb./acre and 14 lb./acre and compared to an untreated check in 4 experiments in 1996 and 1997 in Buckeye, Az. Treatments were made just prior to early bloom. Lygus counts were taken using a sweep net on weekly intervals for four to six weeks post application. A net positive return on investment (ROI) ranging from $34.79/acre to $48.19/acre was realized in three of the four experiments with the seven lb./acre rate. One experiment resulted in a net economic loss of $24.84. A net positive ROI was experienced in two of the four experiments ranging from $23.31 to $50.11 using the fourteen lb./acre Temik rate. Two of the four experiments resulted in a net loss ranging from $28.28 to $93.27 using the fourteen lb./acre rate. It appears that lint yield increase responses are due in part to a plant response to Temik, not necessarily related to lygus density as evidenced in part by the lack of measured sweep count populations.
23
Husman, S. H., and B. Deeter. "Side-Dress Temik® Effects on Lint Yields." College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/211107.
Testo completoAbstract (sommario):
Temik 15G was side -dressed at a rate of 7 lb./acre and 14 lb./acre and compared to an untreated check in two experiments in Buckeye, Az.. Treatments were made prior to the second in- season irrigation (June 3 and June 5) which was just prior to early bloom. Lygus counts were taken using a sweep net on weekly intervals for six weeks post application. The first experiment resulted in a significant increase of 123 lb. and 1241b. lint in both the 7 and 14 lb. rate treatment respectively over the untreated check. The second experiment resulted in a significant 102 lb. lint increase for the 7 lb. treatment with no significant difference for the 14 lb. treatment to the check.
24
Hoffmann, Ryan Carl. "Electron-Induced Electron Yields of Uncharged Insulating Materials." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/749.
Testo completoAbstract (sommario):
Presented here are electron-induced electron yield measurements from high-resistivity, high-yield materials to support a model for the yield of uncharged insulators. These measurements are made using a low-fluence, pulsed electron beam and charge neutralization to minimize charge accumulation. They show charging induced changes in the total yield, as much as 75%, even for incident electron fluences of <3 fC/mm2, when compared to an uncharged yield. The evolution of the yield as charge accumulates in the material is described in terms of electron recapture, based on the extended Chung and Everhart model of the electron emission spectrum and the dual dynamic layer model for internal charge distribution. This model is used to explain charge-induced total yield modification measured in high-yield ceramics, and to provide a method for determining electron yield of uncharged, highly insulating, high-yield materials. A sequence of materials with progressively greater charge susceptibility is presented. This series starts with low-yield Kapton derivative called CP1, then considers a moderate-yield material, Kapton HN, and ends with a high-yield ceramic, polycrystalline aluminum oxide. Applicability of conductivity (both radiation induced conductivity (RIC) and dark current conductivity) to the yield is addressed. Relevance of these results to spacecraft charging is also discussed.
25
Arpiwi, Ni Luh. "The application of novel methods for increasing the yield of small round seed potatoes (Solanum tuberosum L.) varieties Atlantic and Granola." University of Western Australia. School of Plant Biology, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0020.
Testo completoAbstract (sommario):
Potato (Solanum tuberosum L.) varieties Atlantic and Granola are widely grown in Indonesia. The optimal method of cultivation in the tropics, due to the susceptibility of cut seed for disease, is by small (20 to 55 g) whole seed potatoes. However, the variety Atlantic produces mostly large tubers, which are not suitable for planting as whole seeds. Although Granola produces a reasonable proportion of small tubers it still produces a few in the larger size grades and there is no fresh market in Western Australia for the larger tubers for this variety. The aim of this study was to develop methods to be used in Western Australia that improve the yield of small seed potatoes for export to Indonesia. The influence of seed-potato storage duration (at 4°C) on subsequent stem growth was assessed after 30 days growth in a glasshouse (22°C/18°C, day⁄night). Seed potato storage for 22-28 (Atlantic) and 24-30 (Granola) weeks resulted in development of higher numbers of stems. A series of field experiment were designed to increase yield of small tubers. Apical sprout removal in Granola, but not Atlantic, increased the number of stems (by 27%), yield of 20-55 g potato (by 32%) and total yield (by 17%). Application of herbicide (paraquat + diquat) at low concentration during early tuber initiation decreased total yield in Atlantic (by 14%) and Granola (by 16%). Treating whole seed potatoes with carvone vapor two weeks before planting had no influence on stem or tuber number in both Atlantic and Granola but in Atlantic only, the total yield was reduced by 12%. Spraying plants with paclobutrazol during early tuber initiation inconsistently influenced tuber number and yield between the two varieties and two experiments. The influence of gibberellic acid (GA3) on stem number, total tuber number, yield of 20-55 g tubers and total yield was investigated by dipping seed pieces in a GA3 solution (20 mg⁄L) two days prior to planting. In Atlantic, GA3 treatment increased stem number (by 147%), total tuber number (by 75%) and yield of 20-55 g tubers (by 330%) without influencing total yield. In Granola, GA3 treatment increased stem number (by 50%), total tuber number (by 15%), yield of 20-55 g tubers (by 21%) and total yield (by 10%) The influence of gibberellic acid application (20 mg⁄L) to seed pieces before planting increased the number of small tubers through increased stem number. The shift toward a greater proportion of small tubers, without reducing total yield, had a greater influence in Atlantic than that in Granola. Treatment of GA3 and paclobutrazol together decreased total yield compared to that of GA3 alone
26
Acharya, Umesh. "Can We Increase Crop Yield Adopting Tile Drainage in Fargo Clay Soil?" Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28849.
Testo completoAbstract (sommario):
Subsurface drainage has recently become common for agriculturally productive soils and key to maintain and improve crop production in poorly drained, frigid clay soils. The first study was conducted for four years (2014-17) at Casselton, ND to determine best combination of drainage, tillage and crop rotation for higher corn yield. Our finding suggested corn yield was highest with no drainage, CS and CH combination in years with drought conditions. The second study was conducted for three years (2015-17) to evaluate subsurface drainage spacing (9, 12, and 15m) and depth (0.9 and 1.2m) combination on corn, soybean and sugarbeet yields and residual soil nitrate-nitrogen (NO3-N) contents. Results indicated that 9 m drain spacing produced highest corn and soybean yield when average across three years in contrast with drain depth that has no effect on corn and soybean yield except for sugarbeet where the 1.2m depth yielded higher than the 0.9m depth.<br>North Dakota Corn Council<br>North Dakota Soybean Council<br>North Dakota Water Resources Research Institute
27
Hammond, David. "Human smoking behaviour, cigarette testing protocols, and constituent yields." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/737.
Testo completoAbstract (sommario):
The issue of how to test and ultimately regulate tobacco products represents a critical challenge for the public health community. Although the current international testing regime for conventional cigarettes is widely acknowledged to be seriously flawed, there is a lack of data to guide potential alternatives, particularly in the area of human puffing behaviour. The current study sought to: 1) collect naturalistic measures of smoking behaviour, 2) examine the extent to which levels of tar, nicotine, and carbon monoxide from each of five testing protocols were associated with measures of nicotine uptake among smokers, and 3) examine the validity of self-report measures of smoking behaviour. These questions were examined through two different studies. First, a field study of smoking behaviour was conducted with 59 adult smokers, who used a portable device to measure smoking topography over the course of 3 one-week trials. Participants were asked to smoke their usual ?regular-yield? brand through the device for Trial 1 and again, 6 weeks later, at Trial 2. Half the subjects were then randomly assigned to smoke a ?low-yield? brand for Trial 3. The smoke intake and constituent yield of each brand was then tested under five testing protocols: ISO, Massachusetts, Canadian, a Compensatory protocol, and a Human Mimic regime. Participants also completed self-report measures of puffing behaviour at recruitment and immediately following each of the three one-week smoking trials. Several of these self-report measures were subsequently included in the Waves 2 and 3 of the International Tobacco Control Policy Evaluation (ITC) Survey?an international cohort survey of adult smokers from Canada, Australia, the US, and the UK. <br /><br /> The results of the field study indicate a high degree of stability in puffing behaviour within the same smoker over time, but considerable variability between smokers, including those smoking the same brand. Puffing behaviour was strongly associated with cotinine levels, particularly when included in an interaction term with cigarettes per day (<em>Part r</em> = . 50, <em>p</em><. 001). Smokers who were switched to a ?low-yield? cigarette increased their total smoke intake per cigarette by 40% (<em>p</em>=. 007), with no significant change in their in salivary cotinine levels. <br /><br /> The results indicate systematic differences between human puffing behaviour and the puffing regimes used by machine testing protocols. The puffing behaviour observed among participants during the one-week smoking trials was significantly more intense than the puffing parameters of the ISO and Compensatory testing regimes. When cigarette brands were machine tested using participants? actual puffing behaviour, the results suggest that participants ingested two to four times the level of tar, nicotine, and carbon monoxide indicated by the ISO regime, and twice the amounts generated by the Compensatory regime for ?regular-yield? brands. The Canadian and Massachusetts regimes produced yields much closer to the ?Human Mimic? yields, although nowhere near a maximum or intense standard, as they were designed to do. Only the nicotine yields from the Human Mimic regime were correlated with measures of nicotine uptake among smokers, and only moderately so (<em>Part r</em> = . 31, <em>p</em>=. 02). <br /><br /> Self-report measures of puffing behaviour collected during the field study were moderately correlated with physiological measures of puffing and exposure. Self-report measures of puff depth and puff number showed some promise as predictors of salivary cotinine, although the results are characterized by inconsistencies across models. The self-report measures included in the ITC survey were only weakly associated with age and cigarettes per day, with modest between-country differences. <br /><br /> Overall, this research highlights the importance of puffing behaviour as a determinant of smoke exposure, and provides strong evidence of compensatory smoking for ?low-yield? brands. The findings also highlight the variability in human smoking behaviour and the limitations associated with machine testing protocols. Perhaps most important, the findings underscore the immediate need to revise the ISO protocol, which systematically underestimates smoking behaviour among humans and exaggerates differences between cigarette brands.
28
Laprevote, James Arthur, and James Arthur Laprevote. "Suspended sediment yields for selected watersheds in western Montana." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/626812.
Testo completoAbstract (sommario):
Annual suspended sediment yields for 17 watersheds in western Montana in a mild
drought are recalculated. Previous methodology used sporadic to weekly direct
measurements taken only during the annual snowmelt during the drought to estimate
drought period yields. Yield approximations for wet period flows relied on predicted
increases in the means of flow and sediment concentration of the measured values.
This study uses synthetic flow duration curves developed using regional data of a
longer period of record for drought and wet period estimates. These are combined
with log-transformed sediment rating curves which are bias corrected. Mean flows
for the drought average of half previous calculations, sediment yields average 70
percent less. The bias correction averages + 33 percent. Estimates of sediment yield
due to increases in flow are 60 percent less than previous approximations.
29
Xu, Youjie. "Integrated bioprocess to boost cellulosic bioethanol titers and yields." Diss., Kansas State University, 2018. http://hdl.handle.net/2097/38754.
Testo completoAbstract (sommario):
Doctor of Philosophy<br>Department of Biological & Agricultural Engineering<br>Donghai Wang<br>Among potential alternative liquid fuels, bioethanol is the widest utilized transportation fuels and mainly made from grains. Cellulosic biofuels provide environmental benefits not available from grain or sugar-based biofuels and are considered as a solid foundation to meet transportation fuels needs in a low-carbon economy, albeit with electrified vehicles and other technical advances. The objective of this research was to develop and optimize various bioprocessing units to boost cellulosic bioethanol titers and yields in order to accelerate the commercialization of cellulosic bioethanol production.
The results showed high-solids biomass bioconversion (12%, w/v) was inefficient in the laboratory rotary shaker. However, a horizontal reactor with good mixing was effective for high solids loading (20%, w/v), yielding 75 g/L of glucose. To achieve the minimal economical ethanol distillation requirement of 40 g/L, integrated bioprocesses were conducted to boost ethanol titers and yields through co-fermentation of starchy grain and cellulosic biomass. The maximum ethanol concentration (68.7 g/L) was achieved at the corn flour and hydrothermal-treated corn stover ratio of 12:12 using raw starch granular enzyme with the ethanol yield of 86.0%. Co-fermentation of starchy substrate with hydrolysate liquor from saccharified biomass was able to significantly enhance ethanol concentration and reduce energy cost for distillation without sacrificing ethanol yields. These results indicated integration of first and second generation ethanol production could significantly accelerate the commercialization of cellulosic biofuel production. Novel technology, modified simultaneous saccharification and fermentation, was firstly established to enhance ethanol titers and yields, which achieved high ethanol titers of 72.3 g/L at high biomass loadings of 30% (w/v) with 70.0% ethanol yield.
30
Hutcheson, Ryan Mitchell. "Quantitative prediction of dye fluorescence quantum yields in proteins." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/hutcheson/HutchesonR0509.pdf.
Testo completoAbstract (sommario):
The application of a method previously developed by Callis et al. to predict the quantum yields of Trp fluorescence has been successfully applied to the fluorescence of fluorescein and flavins in proteins. The calculated lifetime range of 2 ps - 4 ns is in agreement with experiment. The fluctuations in the electron transfer rate are shown to be dictated by the fluctuations in the density of states. This is evident by the comparison of the fractional deviation of the interaction, density of states and the rate. Here the fluctuations in the density of states is an order of magnitude larger than the fluctuations in the interactions and is nearly the same as that of the kET fluctuations. This demonstrates that the fluorescence lifetime variability is controlled by the electrostatic environment and not the distance dependence of the interaction.
31
Pattison, Charles Andrew Xavier. "Measurement of charged hadron yields for atmospheric neutrino studies." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432564.
Testo completo
32
Reuber, Matthias [Verfasser]. "Stochastic Models for Irradiations and Photovoltaic Yields / Matthias Reuber." München : Verlag Dr. Hut, 2019. http://d-nb.info/1198542659/34.
Testo completo
33
Mattera, Andrea. "Characterization of a Neutron Source for Fission Yields Studies." Licentiate thesis, Uppsala universitet, Tillämpad kärnfysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-238044.
Testo completo
34
Binnie, Robert Cameron. "Factors influencing reproductive sink yields in Phaseolus vulgaris L." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356887.
Testo completo
35
Pickering, Andrew Mark. "Coal liquefaction : prediction of yields and behaviour of blends." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339558.
Testo completo
36
Pander, Banwari Lal. "Genetic studies on test day yields in dairy cattle." Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/12748.
Testo completoAbstract (sommario):
The main aim of this study was to estimate the genetic parameters of test day records of British Holstein-Friesian heifers and to determine how best to use these parameters for generic prediction of lactation performance from test day records. The possibility of reducing the frequency of recording to less often than monthly and procedures for the inclusion of part records in genetic evaluations were also investigated. Estimates of genetic parameters of test day and lactation records were obtained from data on 47736 heifers in 7973 herds, progeny of 40 proven and 707 young sires, using multivariate restricted maximum likelihood methods with a sire model. Average values of heritability estimates for test day records of milk, fat and protein yields and fat and protein contents were 0.36, 0.23, 0.29, 0.36 and 0.36, respectively. Generally, heritability estimates for test day records were lowest at the start and highest in mid and late lactation. Heritability estimates for lactation records of these traits wre 0.49, 0.39, 0.43, 0.63 and 0.47, respectively. Average values of genetic correlations between adjacent TD records of these traits were high (0.92 to 0.97), and the correlations decreased as the interval between tests increased. Genetic correlations of lactation milk yield with fat and protein yields and contents were 0.72, 0.94, -0.56 and -0.53, respectively. Estimates of genetic correlation of test day records with corresponding lactation traits were also high (0.76 to 0.99), being highest in mid lactation.
37
Upton, Kirsty. "Multi-scale modelling of borehole yields in chalk aquifers." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/25403.
Testo completoAbstract (sommario):
A new multi-scale groundwater modelling methodology is presented to simulate pumped water levels in abstraction boreholes accurately within regional groundwater models. This provides a robust tool for assessing the sustainable yield of supply boreholes, thus improving our understanding of groundwater availability during drought. Under UK legislation water companies are required to quantify the reliable, or deployable, output (DO) of all groundwater and surface water sources under drought conditions. However, there is a current lack of appropriate tools for assessing groundwater DO, especially for hydrogeologically complex sources. This is a particular issue for sources in the Chalk aquifer, which is vertically heterogeneous and closely linked with the surface water system. The DO of an abstraction borehole is influenced by processes operating at different scales. The multi-scale model incorporates these processes, providing a new and unique method for simultaneously representing regional groundwater processes, local-scale processes, and features of a borehole. The 3D borehole-scale model solves the Darcy-Forchheimer equation in cylindrical co-ordinates to simulate both linear and non-linear radial flow to a borehole. It represents important features of the borehole itself and incorporates horizontal and vertical aquifer heterogeneity. The radial flow model is embedded within a Cartesian grid using a hybrid radial-Cartesian finite difference method which has not previously been applied in the field of groundwater modelling. A novel methodology is developed to couple this model to a regional groundwater model, ZOOMQ3D, using the OpenMI model linkage software. This provides a flexible and efficient tool for assessing the behaviour of a groundwater source within its regional hydrogeological context during historic droughts and under climate change. The advantages of the new method for calculating the sustainable yield of abstraction boreholes are demonstrated through application to a Chalk supply borehole in the Thames Basin. The multi-scale methodology has many potential applications beyond DO, but provides a valuable tool for water companies to produce a more reliable and robust assessment of groundwater availability, in line with the current water resources planning guidelines.
38
Keller, David Scott. "Factors affecting economic values for yields of milk components /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu148759165817296.
Testo completo
39
LeBlanc, Jeffrey. "Slow Pyrolysis Experiments for High Yields of Solid Carbon." Thesis, The City College of New York, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10256612.
Testo completoAbstract (sommario):
<p> Coal and biomass slow pyrolysis reactions were investigated using thermogravimetric analysis close coupled to gas chromatography (TG-GC). The pyrolysis mass balance via this system was closed to >99 wt. %. Parallel in-situ Diffuse Reflectance Infrared Fourier-Transform Spectroscopy pyrolysis experiments were used to explain the mechanistic relationship between functional groups and volatile products. Gas and tar evolution profiles correspond to the loss of surface oxygenated functional groups and increases in char aromaticity during pyrolysis. Various pyrolysis conditions including heating rates, particle size, and reaction confinements were investigated secondary pyrolysis reactions via TG-GC. The investigation demonstrated that increasing the residence time of tar in the solid-gas interface by 0.23-0.31 seconds results in a 2.1-2.5 wt. % decrease in tar production with a commensurate 0.6-5.7 wt. % increase in solid product, a 40 wt. % increase in CH<sub>4</sub>, and a 10-30 wt. % increase in H<sub> 2</sub> between 510 and 575 °C. Matrix-assisted laser desorption/ionization-time-of-flight mass spectroscopy (MALDI-TOF) measured the molecular weight distribution (MWD) of the pyrolysis tar product to be between 200 and 550 amu. Gas chromatographic-mass spectroscopy (GC-MS) was used to identify 120 distinct species in pyrolysis tar. Tar products of the different reaction conditions show that extended residence time of pyrolysis tars in the solid-gas interface decreased the average MWD, decreased the H/C ratio, and resulted in a more expansive speciation of nitrogen and sulfur species in the tar. Further investigations of tar show that coal tar vaporizes by 1000 ºC without producing secondary gas products or coke. Biomass was found to produce a 40 wt. % char product plus CO<sub> 2</sub>, CO, CH<sub>4</sub>, C<sub>2</sub>H<sub>4</sub>, C<sub>2</sub>H<sub> 6</sub>, and H<sub>2</sub>. The experimentally measured mass closure insists that the product distributions and profiles from slow pyrolysis are absolute and the error may be directly calculated. These are used to estimate the rates, kinetic parameters and number of reactions during pyrolysis.</p>
40
Murray, Eric Charles. "Guidelines for assessing single borehole yields in secondary aquifers." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1005512.
Testo completoAbstract (sommario):
The motivation for this research project arose from the realisation that many South African rural water supply schemes fail due to the over abstraction of groundwater from single boreholes. The main reason for this mis-management of groundwater is a result of inappropriate borehole yield recommendation methods. This research project set out to review existing borehole yield assessment methods and establish new methods which take the shortcomings of existing methods into account. The study is concerned with borehole yield assessment methods applicable to secondary aquifers, since these aquifers are by far the most common in South Africa. The yield assessment methods have been grouped into those that are based on aquifer yield analyses, and on the analysis of single borehole test pump data. In order to assess which methods give suitable yield recommendations, it was necessary to compare the yields obtained using the various methods, with established yields from production boreholes. The focus of the aquifer yield component of the study, was to develop a method for estimating the proportion of recharge that can be abstracted from a single borehole located in a relatively small aquifer. The method was developed by computer simulations of aquifers with different hydraulic properties, and by establishing a formula which describes the relationship between recharge and the abstractable proportion of recharge. Under specific hydrogeological conditions, the recharge based method proved to be reliable in relation to established yields from production boreholes. Of the borehole yield assessment methods based on the analysis of test pump data, none of the existing methods proved to be reliable. However, the yields obtained using the two newly developed methods compared favourably to the established yield of existing production boreholes. Both of these methods are based on the application of the Cooper-Jacob approximation of the Theis equation. This study reviews existing methods and presents newly developed methods for recommending borehole abstraction rates in secondary aquifers. While existing borehole yield assessment methods were found to be unreliable, some of the newly developed methods, if correctly applied, give acceptable yield recommendations.
41
Orlowski, Jan Alexander Kazimierz. "The ENSO Cycle and Predictability of US Crop Yields." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17166.
Testo completoAbstract (sommario):
While the impacts of the El Nino Southern Oscillation (ENSO) are well documented on topics ranging from agricultural production to socio-economic factors, a closer consideration of key interaction terms in this complex relationship is pivotal for better understanding of future production impacts and as well as relevant policy implications. In this thesis, the ENSO link to staple crop production in the US is derived through an econometric approach, in particular taking advantage of recent advances in the nonlinear parameterization of climate variables such as temperature. Via the comparison of competing model specifications, across all major Corn and Soybean producing regions in the United States, the findings of the present study suggest the ENSO link with crop yields manifests itself primarily via extreme degree days. Following this conclusion, this study further extends previous literature by examining the effect of ENSO anomalies on agricultural production in an out-of-sample setting. Optimal producer strategies can be a powerful adaptive measure to anticipated/forecasted ENSO outcomes, predominantly planting date and crop mix. Key results prove valuable to such strategies, particularly in those regions where the channel of ENSO influence for production is obvious, and statistically significant in a pseudo-forecasting environment.
42
Hofmann, Wallace C., and David L. Kittock. "The Effect of Low Quality Seed on Lint Yields." College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219730.
Testo completoAbstract (sommario):
The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.<br>Comparison of 23 low quality upland cotton seed lots with high quality lots in 19 tests over 4 years showed consistent lint yield reduction from low quality seed. The low quality seed lots produced an average of 226 pounds less lint/acre than high quality seed. At $0.60/pound of lint that is $135.37/acre. By analysis of covariance, which adjusted lint yield for equal stand, poor stand explained 162 pounds of lint loss ($97.20/acre) and apparent reduced seedling vigor accounted for 64 pounds of lint loss or $38.16/acre.
43
Boninsegna, José A., and Richard L. Holmes. "Fitzroya Cupressoides Yields 1534-Year Long South American Chronology." Tree-Ring Society, 1985. http://hdl.handle.net/10150/261336.
Testo completoAbstract (sommario):
The longest tree-ring chronologies for the Southern Hemisphere published to date go back to A.D. 1011 in central Chile; 1028 in Tasmania, Australia; 1140 in western Argentina; and 1256 on the North Island, New Zealand. For paleoclimatic and other studies longer time series would be very desirable. Here we report on the first successful crossdating and chronology development for Fitzroya cupressoides, a redwood-like conifer in western Argentina, which goes back to 441 and exhibits desirable statistical characteristics.
44
Lloyd, Simon Phillip. "An analysis of monetary policy transmission through bond yields." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/270003.
Testo completoAbstract (sommario):
In this thesis, I study the transmission of monetary policy through the term structure of interest rates. This is an important topic because, with short-term nominal interest rates in many advanced economies close to their effective lower bound since 2008-2009, central banks have used `unconventional' monetary policies, such as large-scale asset purchases and forward guidance, to stimulate macroeconomic activity by, inter alia, placing downward pressure on longer-term interest rates. I focus on the mechanisms through which monetary policy influences bond yields, domestically and globally, with reference to a canonical decomposition of longer-term interest rates into expectations of future short-term interest rates, and term premia. After an introduction in chapter 1, chapter 2 appraises the use of overnight indexed swap (OIS) rates as measures of expected future monetary policy. Unlike federal funds futures (FFFs), which have regularly been used to construct measures of US interest rate expectations, OIS rates are available in many countries. I find that US OIS rates provide measures of interest rate expectations that are as good as those from FFFs, and that US, UK, Eurozone and Japanese OIS rates up to a 2-year horizon tend to accurately measure interest rate expectations, providing comparable cross-country measures of monetary policy expectations. In chapter 3, I propose a novel method for estimating interest rate expectations and term premia at short and long-term horizons: a no-arbitrage Gaussian affine dynamic term structure model (GADTSM) augmented with OIS rates. Using 3 to 24-month OIS rates, the OIS-augmented model generates estimates of the expected path of short-term interest rates out to a 10-year horizon that closely correspond to those implied by FFFs rates and survey expectations, outperforming existing GADTSMs. I study the transmission of US unconventional monetary policies in chapter 4. Using the OIS-augmented GADTSM, I carry out an event study to demonstrate that US unconventional monetary policy announcements between November 2008 and April 2013 did significantly reduce US longer-term interest rates by affecting expectations and term premia. As a result of these declines, unconventional monetary policies aided US real economic outcomes. Using a structural vector autoregression, I show that changes in interest rate expectations, linked to monetary policy signalling, had more expansionary effects on US real economic outcomes than changes in term premia, associated with portfolio rebalancing. Chapter 5 assesses the international transmission of monetary policy through the term structure of interest rates between advanced economies. I present a micro-founded, two-country model with endogenous portfolio choice amongst country-specific short and long-term bonds, and equity. Within the model, US monetary policy has sizeable effects on longer-term interest rates in other advanced economies, which are similar to empirical estimates. Using the OIS-augmented GADTSM in an event study, I show that US monetary policy has led to changes in interest rate expectations in other advanced economies that amplify global spillovers, which have been partly mitigated by changes in term premia through portfolio rebalancing.
45
Bulman, Patrick G. M. "Management and cultivar effects on the yield and grain protein of spring barley (Hordeum vulgare L.)." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41104.
Testo completoAbstract (sommario):
Spring barley (Hordeum vulgare L.) is an important cereal crop in Quebec, where it is used as a crop for swine and poultry. Since barley is a better source of energy than protein, a protein supplement must be added to the feed. Consequently, the production of barley with high protein concentration in the grain (GPC) is desirable. Studies on intensive cereal management (ICM) practices in other countries have shown that high yields can be combined with a high GPC. From 1987 to 1990 three field experiments were conducted to evaluate the effects of ICM on the yields and GPC of six-rowed spring barley in Quebec. Our results describe the effects of individual ICM components (N fertilizer application, fungicide, and plant growth regulator) on the development of yield components and on GPC. In general, N had little effect on main stem yield spike$ sp{-1}$ and on tiller spikes m$ sp{-2}$. Possibly, plant density or environmental conditions may have imposed greater limitations on yield rather than N. Nitrogen treatments increased GPC generally by increasing the amount of protein grain$ sp{-1}$. Nitrogen treatments which increased the amount of protein grain$ sp{-1}$ increased the lysine and cyst(e)ine concentrations of the grain but decreased their concentration in the grain protein. The plant growth regulator ethephon increased GPC by increasing the amount of protein grain$ sp{-1}$, by decreasing the nonprotein content grain$ sp{-1}$, or by altering final grain size distribution. Ethephon often had damaging effects on yield. Large genotypic variation was observed for GPC, but could not be related to genotypic differences in N harvest index, total N accumulation, protein yield or post-anthesis N uptake and assimilation. Grain yield was weakly correlated with GPC. Examination of the cultivars grown from 1910 to 1988 showed that increases in grain yield were accompanied by increases in harvest index, total dry matter, and lodging resistance. Plant height was reduced over tim
46
Hem, Inthavong Khamla. "Factors influencing rice production efficiency in Ban Home, Laos." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99183.
Testo completoAbstract (sommario):
Agriculture remains a dominant economic sector in many developing countries. Rice constitutes a staple food for more than half of the world's population and is the main meal of all Lao people (FAO, 2005). However, rice production faces many problems, including the effects of floods, drought and poor soil quality. These challenges combine to reduce rice productivity below what might be possible. However, before new agricultural policies are put in place, it is important to identify the factors associated with rice production efficiency. This thesis analyses technical and socio-economic factors that influence rice production and estimates the level of technical efficiency of individual rice farmers in Ban Home, Laos.<br>Survey data were collected in the region in 2003, for both wet season and dry season rice production. Using these data, a Cobb-Douglas frontier production function was estimated for each season using two approaches, deterministic and stochastic. During the wet season, several factors were statistically significant and positive in their effect on rice yield: area in rice production, level of fertilizer use, total labour, the use of a modern variety, sandy soil and contact with a professional agricultural advisor. During the dry season, only area in rice production and fertilizer were significant. Based on the frontier production functions, it is possible to conclude that the average technical efficiency of farmers is higher during the dry season than the wet season, for both the deterministic and stochastic approaches.<br>However, socio-economic factors were unable to explain the level of technical efficiency among farmers, when evaluated using a standard regression approach. By using a simple t-test to compare the mean level of efficiency of different groups of farmers, some significant differences emerged. Farmers who used credit were found to be more efficient than those who did not. Moreover, experienced farmers were more efficient than less experienced farmers. Also, farmers with less than 7 years of education were more efficient than more educated farmers.
47
Assad, Muhammad Arif. "The influence of altering concentrate dietary energy source on the performance of lactating dairy cows." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366642.
Testo completo
48
Lavorenti, Norberto A. "Fitting models in a bivariate analaysis of intercropping." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266039.
Testo completo
49
Taylor, Victoria Jane. "The growth hormone (GH) and insuling-like growth factor (IGF) axis in relation to fertility in the high yielding dairy cow." Thesis, Royal Veterinary College (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246921.
Testo completo
50
Readman, Russell J. "The physiological basis and consequences for nitrate leaching of novel fertiliser strategies involving foliar fertilisation of wheat." Thesis, Open University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321312.
Testo completo