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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Dry-Farming in the Arid Southwest

Clothier, R. W. 01 February 1913 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
232

ミャンマー、ドライゾーンにおける作付体系動態の解析 / Analysis of Dynamics of Cropping Systems in the Dry Zone, Myanmar

Moe, Swe Yee 23 March 2015 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(農学) / 甲第19044号 / 農博第2122号 / 新制||農||1032 / 31995 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 白岩 立彦 / 学位規則第4条第1項該当
233

The production economics of red deer husbandry for commercial venison

Paluchowski, T. January 1977 (has links)
The thesis is concerned with the study of the economics of venison production in Scotland. It examines the various production systems utilised at present both in the wild and on an intensive farm and analyses the factors affecting productivity and their relative importance in each system. The evolution of the red deer in Scotland and more recent developments in the market for venison are examined in the early chapters. In addition, the production system in the wild is analysed and a production function is developed. In order to study the population dynamics of the red deer, a mathematical model is constructed. This is used in conjunction with the production function developed previously to illustrate the interaction between the ecological and economic factors which govern the productivity of red deer populations. In the light of this analysis, a number of recommendations are made for the improvement of productivity in the wild. The limitations of this production system, however, pose a problem for the practical implementation of such proposals. To some extent, these may be overcome by the adoption of a more intensive production system, although this in turn creates its own problems. The second part of this thesis is thus concerned with the study of the intensive system. The experimental deer farm at Glensaugh forms the basis f~ the investigation of this system. The data thus obtained are used in conjunction with a modified version of the mathematical model previously developed. This is incorporated in a linear programming format so that the farming system may be analysed and the operating strategies compared. The objective of the analysis is to determine which factors exert the greatest influence upon the operating strategies in terms of operating profit. Once these critical areas are identified, research effort may be directed more effectively to improve the system performance. The above analysis leads to a number of recommendations regarding' the operating strategies on a deer farm. The financial aspects of such an operation are examined and provide some basis against which the future viability of the farming operation might be assessed. No attempt is made to define levels of acceptable returns on investment. The intention is rather to determine the effects which changes in the economic and environmental conditions have upon investment potential. Although this study provides some tentative solutions as to how improvements in productivity may be obtained these should not be regarded as final. As knowledge of the production system improves, the solutions to the problems will change as will the problems themselves.
234

When the well runs dry : groundwater management in Texas

Reel, Jennifer Lynne 30 November 2010 (has links)
Managing and protecting our water resources is one of the most pressing long-term issues facing Texas. In addition to population growth, Texas' vulnerability to drought makes long-term water planning both challenging and imperative. As competing interests vie for this limited natural resource, the State struggles to reach solutions that can provide sustainable water for everyone. This report, and the accompanying video, Tecolote, examine the management of Texas groundwater and the impact it has on Tecolote Farms. / text
235

Βιολογική καλλιέργεια γλυκού σόργου [Sorghum bicolor (L.) Moench] για παραγωγή βιομάζας : επίδραση της έλλειψης νερού στην εδαφική υγρασία σε φυσιολογικές παραμέτρους και στις αποδόσεις της καλλιέργειας

Καμπράνης, Αναστάσιος 17 October 2008 (has links)
Η καλλιέργεια του γλυκού σόργου [Sorghum bicolor (L.) Moench] θεωρείται ως μια από τις προτεινόμενες ενεργειακές καλλιέργειες προκειμένου να αξιοποιηθεί για την παραγωγή βιο-αιθανόλης στα Μεσογειακά οικοσυστήματα. Σ΄ αυτά τα συστήματα το νερό αποτελεί φυσικό πόρο υπό έλλειψη και η χρήση του θα πρέπει να γίνεται με σχεδιασμό σύμφωνα με τις ανάγκες των καλλιεργειών. Η καλλιέργεια του γλυκού σόργου στη Δ. Ελλάδα την περίοδο του θέρους συχνά υπόκειται σε υδατική καταπόνηση. Προς τούτο στο αγρόκτημα του Πανεπιστημίου Πατρών τις καλλιεργητικές περιόδους 2003-2004 & 2004-2005 εγκαταστάθηκαν πειράματα πεδίου με στόχο τη μελέτη της επίδρασης δύο χειρισμών της γονιμότητας του εδάφους και διαφορετικών επιπέδων άρδευσης και σε μια σειρά παραμέτρους όπως: Οι αποδόσεις της καλλιέργειας σε βιομάζα και σάκχαρα, στους δείκτες αύξησης, «Ρυθμός Aύξησης της Kαλλιέργειας, CGR», και «Δείκτη φυλλικής επιφάνειας LAI». Επίσης μελετήθηκε η επίδραση των δύο χειρισμών της γονιμότητας του εδάφους στη φωτοσυνθετική δραστηριότητα των φύλλων των φυτών. Υπολογίστηκαν οι ανάγκες της καλλιέργειας σε νερό με βάση τον υπολογισμό της εξατμισοδιαπνοής κατά Pemnan-Monteith (Μοντέλο FAO) και το προταθέν μοντέλο από τους ερευνητές Δέρκα και Λιακάτα στις εδαφοκλιματικές συνθήκες του Πανεπιστημίου Πατρών (Ρίον). Παράλληλα έγινε σύγκριση των δεδομένων με μετρήσεις της διαπνοής με τη μέθοδο της ροής των χυμών. Ο παράγοντας - χειρισμός της γονιμότητας του εδάφους – ορίστηκε ως «συμβατικός» και «βιολογικός» χειρισμός ενώ για κάθε συνδυασμό χειρισμών υπήρχαν τρεις επαναλήψεις. Για την καλλιεργητική περίοδο 2003-2004 και για το επίπεδο άρδευσης Ι1=420 mm (πλήρη άρδευση) οι αποδόσεις σε νωπή βιομάζα ( βλαστοί και φύλλα ) ήταν στο «συμβατικό» χειρισμό του εδάφους 8,71±0,2 Kgm-2 και στον «βιολογικό» χειρισμό του εδάφους 8,6±0,06 Kgm-2 αντίστοιχα. Οι αποδόσεις σε ξηρά βιομάζα ήταν αντίστοιχα για τον «συμβατικό» χειρισμό του εδάφους 2,29±0,055 Kgm-2 και για τον «βιολογικό» χειρισμό του εδάφους 2,4±0,036 Kgm-2 . Για το επίπεδο άρδευσης Ι2=170 mm οι αποδόσεις σε νωπή βιομάζα ( βλαστοί και φύλλα ) ήταν στο «συμβατικό» χειρισμό του εδάφους 8,29±1,2 Kgm-2 και στον «βιολογικό» χειρισμό του εδάφους 6,12±0,5 Kgm-2 αντίστοιχα. Οι αποδόσεις σε ξηρά βιομάζα ήταν αντίστοιχα για τον «συμβατικό» χειρισμό του εδάφους 2,76±0,367 Kgm-2 και για τον «βιολογικό» χειρισμό του εδάφους 2,04±0,18 Kgm-2 Για την καλλιεργητική περίοδο του 2004 - 2005 για το επίπεδο άρδευσης Ι1=515 mm οι αποδόσεις σε νωπή βιομάζα ήταν στο «συμβατικό» χειρισμό του εδάφους 10,63±0,645 Kgm-2 ολικής ΝΒ, 9,47±0,6 Kgm-2 ΝΒ στελεχών (ποσοστό 89,08%) και 3,94±0,17 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 10,6±0,096 Kg m-2, 9,57±0,6 Kg m-2 (ποσοστό 90,28%) και 3,96±0,42 Kg m-2. Για το επίπεδο άρδευσης Ι2=303mm στο «συμβατικό» χειρισμό 7,54±0,452 Kgm-2 ολικής ΝΒ, 6,58±0,38 Kgm-2 ΝΒ στελεχών (ποσοστό 87,26%) και 2,66±0,215 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 9,22±0,447 Kg m-2, 8,3±0,527 Kg m-2 (90,2%) και 3,13±0,209 Kg m-2. Για το επίπεδο άρδευσης Ι3=230mm στο «συμβατικό» χειρισμό 7,67±0,538 Kgm-2 ολικής ΝΒ, 6,78±0,44 Kgm-2 ΝΒ στελεχών (ποσοστό 87,26%) και 2,51±0,23 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 7,89±0,13 Kg m-2, 6,9±0,17 Kg m-2 (90,2%) και 2,76±0,052 Kg m-2. Στατιστική επεξεργασία των αποτελεσμάτων (ANOVA) έδειξε ότι δεν υπάρχουν σημαντικές διαφορές στις αποδόσεις σε βιομάζα μεταξύ των χειρισμών της γονιμότητας του εδάφους. Αντιθέτως διαπιστώθηκαν σημαντικές διαφορές στις αποδόσεις μεταξύ των επιπέδων άρδευσης. Επίσης μελετήθηκε η επίδραση του χρονοδιαγράμματος άρδευσης για τα τρία επίπεδα άρδευσης στις μεταβολές της εδαφικής υγρασίας. / The cultivation of sweet sorghum [Sorghum bicolor (L.) Moench] is considered a proposed energy crops in order to be used in the production of bio – ethanol in Mediterranean ecosystems. Water consists a resource in shortage in these ecosystems and its use must be organized according to cultivation needs. Sweet sorghum crops in western Greece during summer frequently undergoes water deprivation therefore, field studies have been conducted in the University of Patras farm during the agricultural periods 2003 – 2004 & 2004 – 2005 aiming the study of the influence of two manipulation of soil fertility and levels of irrigation as well as a Sevier of parameters such as: The crops yields in biomass, sugar and growth rates « Crop Growth Rate », CGR and « Leaf Area Index », LAI. Furthermore the influence of two manipulation of soil fertility on the photosynthetic activity of plant leaves has been studied. The needs of the crop in water have been calculation of evapotranspiration according to Penman-Monteith ( FAO model ) and the proposed model by researchers Derca and Liakata in the soil climatic conditions of Patras University ( Rion ). Simultaneously the data have been compared to measurements of transpiration with the Sap Flow method. The factor – soil fertility manipulation – was determined as «conventional» and «biological» manipulation while for every combination three repetitions were made. For agricultural period 2003-2004 and for an irrigation level Ι1=420 mm «full irrigation» the yields in fresh biomass ( stems and leaves ) were with the «conventional» manipulation of 8,71±0,2 Kgm-2 and with the «biological» manipulation of the soil 8,6±0,06 Kgm-2 respectively. The yields dry biomass were respectively with the «conventional» manipulation of the soil 2,29±0,055 Kgm-2 and with the «biological» manipulation 2,4±0,036 Kgm-2 . For an irrigation level Ι2=170 mm the crop yield in fresh biomass ( stems and leaves ) were with the «conventional» manipulation of 8,29±1,2 Kgm-2 and with the «biological» 6,12±0,5 Kgm-2 respectively. The yields dry biomass were respectively with the «conventional» manipulation of the soil 2,76±0,367 Kgm-2 and with the «biological» 6,12±0,5 Kgm-2 respectively 2,04±0,18 Kgm-2. For the agricultural period 2004 – 2005 and with an irrigation level Ι1=515 mm the crop yields in fresh biomass were with the «conventional» soil 10,63±0,645 Kgm-2 total FB ( fresh biomass ) 9,47±0,6 Kgm-2 FB of stems (89,08%) και 3,94±0,17 Kgm-2 total DB (Dry biomass). Respectively with the «biological» soil manipulation 10,6±0,096 Kg m-2, 9,57±0,6 Kg m-2 (90,28%) and 3,96±0,42 Kg m-2. For irrigation level Ι2=303mm with the «conventional» manipulation 7,54±0,452 Kgm-2 total FB, 6,58±0,38 Kgm-2 FB of stems (87,26%) and 2,66±0,215 Kgm-2 total DB. Respectively with the «biological» manipulation 9,22±0,447 Kg m-2, 8,3±0,527 Kg m-2 (90,2%) and 3,13±0,209 Kg m-2. For irrigation level Ι3=230mm with the «conventional» manipulation 7,67±0,538 Kgm-2 total FB, 6,78±0,44 Kgm-2 FB of stems (87,26%) and 2,51±0,23 Kgm-2 total DB. Respectively with the «biological» manipulation 7,89±0,13 Kg m-2, 6,9±0,17 Kg m-2 (90,2%) and 2,76±0,052 Kg m-2. Statistical processing of the results (ANOVA) showed that there are no significant differences in crops biomass yields between the two soil manipulations on the contrary. Significant differences were established between the different irrigation levels in addition, the influence of the irrigation schedule on the variations of soil moisture were examined for the three irrigation levels.
236

Extended Use of Treated Municipal Wastewater by the Buckeye Irrigation Company: A Documentation of Effects

Cluff, C. B., Tucker, T. C., Day, A. D., McFadyen, John A., Sebenik, Paul G. 09 1900 (has links)
Project Completion Report, OWRT Project No. A-050-ARIZ. / Agreement No. 14-31-0001-5003 / Project Dates: July 1974 - June 1976. / The work upon which this publication was based was supported in part by funds provided by the Office of Water Research and Technology (A-050-ARIZ), U.S. Department of the Interior, Washington, D.C., as authorized by the Water Research and Development Act of 1978. / INTRODUCTION: The use of treated sewage effluent by the Buckeye Irrigation Company began with 800 acre -feet in 1962 and had increased to 40,000 a.f. by 1968. The effluent was diverted by the Buckeye Irrigation Company from the Gila River approximately seven miles below the City of Phoenix 91st Avenue treatment plant, as it became available at their diversion point. Natural streamflow, used in earlier years, had virtually stopped due to upstream development except in heavy runoff years such as 1941. The ground water in the district of the Buckeye Irrigation Company is relatively high in dissolved solids. The quality of the treated effluent is better. In 1971 the company signed a 40 -year contract with Phoenix to assure its use of 30,000 a.f. of effluent per year. The effluent is mixed with native ground water to bring the total water applied on the 18,000-acre district up to approximately 90,000 a.f. (Halpenny, 1973). The treated effluent use by the Buckeye Irrigation Company is the largest in the State of Arizona and one of the largest land applications of treated effluent in the United States. It is unique in that it is being utilized by an irrigation district. Most other uses have been by city operated farms or private farms under a single ownership. In spite of its uniqueness the effects of effluent use by the Buckeye Irrigation District had not, prior to this research, been well documented. This documentation was made in order to improve the general knowledge needed to extend this type of use to other areas in the state and nation. "Widespread consideration and utilization of land application cannot be made until such time as adequate information concerning the technique involved is made available. The experience gained by those who have successfully utilized this wastewater management should be used... specific evaluation of established systems in the various climatic zones would appear to be more fruitful than new research installations for determining long term effects on soils, vegetation, ground water and the indigenous ecology..." (Sullivan, et al., 1973). During the two year research period most of the initial objectives were achieved. The original specific objectives were: 1. To identify changes during an extended period of application of treated wastewater to irrigated fields in: a. irrigation practices b. cropping patterns c. fertilization practices d. crop yield response and quality e. quality of irrigation water, and f. soil properties. 2. To make a preliminary evaluation of the effects of the use of effluent on ground-water conditions. 3. To make a preliminary evaluation of changes in water costs and farm profits.
237

Economic factors affecting the long term outlook for irrigated farming in Sulphur Springs Valley, Arizona

Lee, Verren Wilson, 1939- January 1967 (has links)
No description available.
238

Design of an autonomous navigation system for a mobile robot

Paul, André. January 2005 (has links)
An autonomous navigational system for a mobile robot was developed based on a Laser-Range-Finder-based path planning and navigational algorithms. The system was enhanced by incorporating collision avoidance algorithms using data from a sonar sensor array, and further improved by establishing two virtual regions in front of the robot for obstacle detection and avoidance. Several virtual detector bands with varying dimensions were also added to the sides of the robot to check for rotational clearance safety and to determine the direction of rotation. The autonomous navigational system was tested extensively under indoor environment. Test results showed that the system performed satisfactorily in navigating the mobile robot in three structured mazes under indoor conditions. / An artificial landmark localization algorithm was also developed to continuously record the positions of the robot whilst it was moving. The algorithm was tested on a grid layout of 6 m x 6 m. The performance of the artificial landmark localization technique was compared with odometric and inertial measurements obtained using a dead-reckoning method and a gyroscope-corrected dead-reckoning method. The artificial landmark localization method resulted in much smaller root mean square error (0.033 m) of position estimates compared to the other two methods (0.175 m and 0.135 m respectively).
239

Growing Indoors to Promote Food Sovereignty

Hocquard, Carolyn 10 July 2012 (has links)
This thesis proposes a destination restaurant, near Tatamagouche, Nova Scotia, Canada, that serves as an informative showcase of common food plants grown indoors, and allows visitors to experience the food cycle of growing, processing, cooking, eating, and composting, from soil to table. Throughout the building, the line between architecture and agriculture is blurred, as program areas incorporate food plants. The environmentally-conscious design, built primarily of re-used wood and locally sourced sandstone, inspires visitors to start growing food at home by being a living example of a variety of growing methods, most of which could be adopted at home on a smaller scale.
240

Efficiency and productivity of Quebec dairy farms

Shanmugam, Ramaradj. January 1998 (has links)
The analysis of cost and profit efficiencies of a sample of 588 Quebec dairy farms shows significant potential to reduce costs and increase profits. In general, the small farms were more cost efficient while large farms were more profit efficient. Increased use of farm grown feed was associated with higher efficiency while increased use of concentrates was associated with lower efficiency. / The productivity of individual dairy farms were estimated using data envelopment analysis. The average annual growth rate of productivity was 0.70% with a standard deviation of 2.44% for the 1987--93 period. The Spearman's rank correlation coefficient did not show any significant relationship between farm size and growth rate. / The Artificial Neural Networks (ANN) approach, used for the first time to estimate technical efficiency, performed equally as good as the regression models in modeling the technology especially at the higher levels of output. The efficiency values estimated using ANN were higher than that estimated by ordinary least squares method. The results indicate the existence of significant potential for improving the efficiency of resources on Quebec dairy farms.

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