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Articles 286861 - 286890 of 303246

Full-Text Articles in Physical Sciences and Mathematics

Periodic Solutions Of Nonlinear Boundary Value Problems, V. Lakshmikantham, R. Kannan Apr 1980

Periodic Solutions Of Nonlinear Boundary Value Problems, V. Lakshmikantham, R. Kannan

Mathematics Technical Papers

One of the well known techniques in the theory of nonlinear boundary value problems (BVP) is the method of differential inequalities or the method of upper and lower solutions. The method of "Alternative Problems", a global variant of the Lyapunov-Schmidt method, has been used in the study of problems at resonance. The investigation of periodic BVP's forms an important subclass of problems at resonance. Our aim is to combine the two approaches to discuss nonlinear problems at resonance. We restrict ourselves in this paper to the discussion of periodic boundary value problems. In Section 1, we shall indicate the method …


Developing Crab Creek : Fifteen Points Of View On Economy And Ecology In An Estuary : A Simulation For Advanced Students Exploring Coastal Resource Management Decisions In Virginia, Frances Lee Lawrence Apr 1980

Developing Crab Creek : Fifteen Points Of View On Economy And Ecology In An Estuary : A Simulation For Advanced Students Exploring Coastal Resource Management Decisions In Virginia, Frances Lee Lawrence

Reports

Crab Creek County is a hypothetical small Virginia county on. the Chesapeake Bay. This· simulation explores the coastal management issues involved in developing a point of land in Crab Creek County fronting on the Chesapeake Bay to the North, and Crab Creek to the South. The game is based on key Virginia and federal laws and agencies affecting coastal resources, and provides insights into the human and technical interactions involved in the "permitting" processes. Players fill fifteen roles representative of private interests as well as local, state, and federal activities. more...


Simultaneous Transport Of Water And 3hoh In Water, H. D. Scott Apr 1980

Simultaneous Transport Of Water And 3hoh In Water, H. D. Scott

Arkansas Water Resources Center Technical Reports

Dispersion of 3HOH was studied at flow velocities less than 14 cm/day in a Captina silt loam using the half-cell technique. Two directions of transport were studied: movement of 3HOH in the same direction as water, and movement of 3HOH in the opposite direction to that of water. Results indicated that the dispersion coefficients were velocity dependent for equilibration times ranging to 21 hours. As the average pore flow velocity increased, the length of time needed for the dispersion coefficients to become independent of the flow velocity increased. When considering transport of 3HOH in the same …


Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb Apr 1980

Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb

OES Theses and Dissertations

Laboratory grazing and assimilation experiments were conducted on the mysid shrimp Neomysis americana in an attempt to assess the suitability of three potential food sources. It was hypothesized that the smaller size classes were primarily herbivores, not becoming omnivorous until attaining lengths of approximately 5-6 mm. Four size classes of mysids from the summer generation, juveniles, immature, adult males, and adult ovigerous females were each fed three concentrations of Artemia salina nauplii, the rotifer Brachionus plicatilis, and the diatom Coscinodiscus lineatus. The mean lengths of the size classes utilized, plus or minus one standard deviation, were 2.5 …


Influence Of Nonequilibrium Radiation And Shape Change On The Flowfield Of A Jupiter Probe With Ablation And Mass Injection, Sundaresa Venkata Subramanian Apr 1980

Influence Of Nonequilibrium Radiation And Shape Change On The Flowfield Of A Jupiter Probe With Ablation And Mass Injection, Sundaresa Venkata Subramanian

Mechanical & Aerospace Engineering Theses & Dissertations

The influence of nonequilibrium radiative energy transfer and the effect of probe configuration changes on the flow phenomena around a Jovian entry body is investigated. The radiating shock-layer flow is assumed to be axisymmetric, viscous, laminar and in chemical equilibrium. The radiative transfer equations are derived under nonequilibrium conditions which include multi-level energy transitions. The equilibrium radiative transfer is calculated with an existing nongray radiation model which accounts for molecular band, atomic line and continuum transitions. The nonequilibrium results are obtained with and without ablation injection in the shock layer. The nonequilibrium results are found to be influenced greatly by …


Surface Circulation And Horizontal Diffusion Processes Of The Lower Chesapeake Bay, Frederick A. Hilder Apr 1980

Surface Circulation And Horizontal Diffusion Processes Of The Lower Chesapeake Bay, Frederick A. Hilder

OES Theses and Dissertations

A Lagrangian method utilizing clusters of four or five buoyed drogues is used to study the surface circulation and horizontal diffusion processes of the lower Chesapeake Bay. The study area encompasses some 160 km2 and includes the area north of Thimble Shoal Channel, southwest of Chesapeake Channel and west of the Chesapeake Bay Bridge and Tunnel. Eleven trials utilizing buoyed drogues were conducted in the time frame February to October, 1979. Four trials were interrupted when buoys entered neighboring channels or dispersed too far for tracking, so that a total of sixteen runs were completed on the eleven trial …


Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston Apr 1980

Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston

OES Theses and Dissertations

Spatial zonation of symbiotic and aposymbiotic forms of the temperate coral Astrangia danae provides evidence that light attenuation is an important factor in the distribution of this animal. At four locations in the lower Chesapeake Bay and adjacent offshore waters, symbiotic colonies were observed only in well illuminated surface waters, while aposymbiotic colonies were observed in less illuminated deeper waters. A transition zone exists in which both colony types are found. Colonies on substrates forming a plane parallel to the sea-surface receive a greater radiant flux than colonies on vertical substrates. This extends the depth range of symbiotic colonies located …


Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne Apr 1980

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …


Isolation And Enumeration Of Enteric Viruses From Primary Wastewater Sludge, Michael Wayne Nath Apr 1980

Isolation And Enumeration Of Enteric Viruses From Primary Wastewater Sludge, Michael Wayne Nath

Biological Sciences Theses & Dissertations

The presence of large numbers of enteric viruses in wastewaters has resulted in concern regarding their significance and consequences for humans. Assessments of relative significance or consequences may most accurately be made following precise measurements of the range of virus types and amounts in wastewaters and sludges and after epidemiological considerations. In this study, results are presented pertaining to enteric virus isolation, concentration, and enumeration from primary wastewater sludges.

As an integral part of a comparison of isolation procedures, several anionic surfactants were examined for extraction of enteric viruses from primary wastewater sludges. Plaquing efficiencies for poliovirus type 2 and …


Variation Of Constants, Vector Lyapunov Functions And Comparison Theorem, A. R. Aftabizadeh Apr 1980

Variation Of Constants, Vector Lyapunov Functions And Comparison Theorem, A. R. Aftabizadeh

Mathematics Technical Papers

In this paper we combine the above ideas to obtain a new comparison result and discuss its relation to known results. A simple application to stability theory is also given to indicate the usefulness of the comparison result. Our result is expected to play a prominent role in the qualitative study of differential equations.


Test 1337: International Hydo 86 Diesel, Nebraska Tractor Test Lab Mar 1980

Test 1337: International Hydo 86 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Test 1336: International 686 Diesel 10-Speed, Nebraska Tractor Test Lab Mar 1980

Test 1336: International 686 Diesel 10-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Test 1338: International 886 Diesel 16-Speed, Nebraska Tractor Test Lab Mar 1980

Test 1338: International 886 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Test 1335: Versatile 895 Diesel 12-Speed, Nebraska Tractor Test Lab Mar 1980

Test 1335: Versatile 895 Diesel 12-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Contribution To Theories Of Repetitive Sampling Strategies., Raghunath Arnab Dr. Mar 1980

Contribution To Theories Of Repetitive Sampling Strategies., Raghunath Arnab Dr.

Doctoral Theses

A common practical problem to whlch a survey - sampler has frequently to address himself 1s one of sampling a given finite population on successive occasions. One of the relevant issues requiring one's attention then 1s to adopt a suitable sampling strategy to estimate the population total of a variate of interest an the current occasion in an optimal manner. Here one has of necessity to take care to utilize the accumalated data on that variate procured in course of the survey along with other auxdliary information on one or more additional variables that may also incidentally be available, Several …


Scs 55: Mc Direct Limits, John R. Isbell Mar 1980

Scs 55: Mc Direct Limits, John R. Isbell

Seminar on Continuity in Semilattices

No abstract provided.


Operational Analysis Based On Minimal Information: A Hypothetical Case Study, Herb Schwetman Mar 1980

Operational Analysis Based On Minimal Information: A Hypothetical Case Study, Herb Schwetman

Department of Computer Science Technical Reports

No abstract provided.


The Problem Of Pika Control In Baluchistan, Pakistan, Abdul Aziz Khan, William R. Smythe Mar 1980

The Problem Of Pika Control In Baluchistan, Pakistan, Abdul Aziz Khan, William R. Smythe

Vertebrate Pest Conference Proceedings: 9th (1980)

The collared pika, Ochotona rufescens has been recorded as a serious pest in apple orchards in the uplands valley of Ziarat in Baluchistan. In the winter, when the natural vegetation is lacking, the pikas debark the apple tree trunks or branches resulting in the killing of the tree and reduced fruit production. In summer, damage to wheat, corn and potatoes is also very severe. It is estimated that pikas cause hundreds of thousands of dollars (US) in annual apple production losses. The apple production in Baluchistan accounts for about 35 percent of the total provincial income through food production. During …


Changes In A Feral Pig Population After Poisoning, James Hone, Henry Pedersen Mar 1980

Changes In A Feral Pig Population After Poisoning, James Hone, Henry Pedersen

Vertebrate Pest Conference Proceedings: 9th (1980)

The changes in a feral pig population associated with 1080 poisoning were examined. There was a 58.1% reduction in population size after poisoning with no age-specific effect. The population size increased over 11.5 months after poisoning at an observed instantaneous rate of increase per year of 0.57. The results are discussed relative to feral pig control.


Recent Developments In Anticoagulant Rodenticide Resistance Studies: Surveillance And Application In The United States, Stephen C. Frantz, Constance M. Padula Mar 1980

Recent Developments In Anticoagulant Rodenticide Resistance Studies: Surveillance And Application In The United States, Stephen C. Frantz, Constance M. Padula

Vertebrate Pest Conference Proceedings: 9th (1980)

Since anticoagulant rodenticide resistance was first discovered in the United States in 1971, it has become apparent that the phenomenon is widespread. In cooperation with the Center for Disease Control, a nationwide surveillance program was initiated in 1977 to obtain statistically valid samples of rats from federally funded projects of the Urban Rat Control Program. A summary is given of the basic sampling, testing, and analysis components of this study. Problems encountered in all aspects of the first three years of the program are discussed along with results from the 40 completed samples. The 16 cities with significant Anticoagulant Resistance …


Opening Comments — Ninth Vertebrate Pest Conference, Jerry P. Clark Mar 1980

Opening Comments — Ninth Vertebrate Pest Conference, Jerry P. Clark

Vertebrate Pest Conference Proceedings: 9th (1980)

Welcoming Statment


Conference Participants Mar 1980

Conference Participants

Vertebrate Pest Conference Proceedings: 9th (1980)

A total of 347 people registered at the Conference. The participants came from 33 states, the District of Columbia, and 20 other countries: Australia, Canada, Colombia, Egypt, England, Ethiopia, Fed. Rep. Germany, India, Iraq, Israel, Italy, Mexico, Nicaragua, Nigeria, Norway, Pakistan, Philippines, Tanzania, Thailand, and Venezuela. The wide representation from the United States and from countries throughout the world contributes to the success of the Conference by providing a highly diversified exchange of ideas and information.


Lithium Chloride Bait Aversion Did Not Influence Prey Killing By Coyotes, Richard J. Burns, Guy E. Connolly Mar 1980

Lithium Chloride Bait Aversion Did Not Influence Prey Killing By Coyotes, Richard J. Burns, Guy E. Connolly

Vertebrate Pest Conference Proceedings: 9th (1980)

Conditioned food or flavor aversion has been proposed as a method to stop coyote predation on sheep. The method entails treating sheep carcasses or meat baits with an emetic, lithium chloride (LiCl), and scattering them on sheep ranges. Theoretically, coyotes eat the baits, become ill, and subsequently desist from killing and eating sheep because they associate sheep flavor with sickness. In recent studies, coyotes have not formed prey aversions. Coyotes avoided baits because of LiCl flavor rather than prey flavor and prey killing aversions were not found. We conducted a study designed to find the best LiCl-prey flesh concentration to …


Hazards To Small Mammals Associated With Underground Strychnine Baiting For Pocket Gophers, Kathleen A. Fagerstone, Victor G. Barnes Jr., R. Michael Anthony, James Evans Mar 1980

Hazards To Small Mammals Associated With Underground Strychnine Baiting For Pocket Gophers, Kathleen A. Fagerstone, Victor G. Barnes Jr., R. Michael Anthony, James Evans

Vertebrate Pest Conference Proceedings: 9th (1980)

Damage to conifer seedlings by pocket gophers (Thomomys spp.) is a major factor limiting reforestation in the western United States. To control gopher populations and reduce damage, the U.S. Forest Service annually treats thousands of hectares with strychnine alkaloid bait. Because an underground application of strychnine bait could pose a threat to other species, we monitored small mammal populations before and after a baiting operation conducted in 1979 on the Targhee National Forest, Idaho. Although two deer mice (Peromyscus maniculatus) recovered within baited areas were killed by strychnine, live-trapping revealed no differences in small mammal populations before and after baiting. …


Deer-Proof Fences For Orchards: A New Look At Economic Feasibility, James W. Caslick Mar 1980

Deer-Proof Fences For Orchards: A New Look At Economic Feasibility, James W. Caslick

Vertebrate Pest Conference Proceedings: 9th (1980)

Woven-wire fences, 2.4-m-high, have proven to be deer-proof and economically feasible for some apple orchards planted to semi-dwarf and dwarf trees, under high-density planting systems. The factors included in a benefit-cost analysis are described, and a formula is given to facilitate a decision about the economic feasibility of investing in a fence of this type.


Armadillos: Problems And Control, Patricia A. Chamberlain Mar 1980

Armadillos: Problems And Control, Patricia A. Chamberlain

Vertebrate Pest Conference Proceedings: 9th (1980)

The nine-banded armadillo (Dasypus novemcinctus) has been successful in extending its range throughout the southeastern states. It occupies such a diverse range of habitats that its effects on its surroundings depend largely on where it is located. It offers benefits from its burrowing and eating patterns by creating dens for furbearers and destroying large quantities of injurious insects and their larva. Those same activities in urban and suburban areas are now being recognized as a source of considerable nuisance and moderate damage. Damage is most severe from July through early November. They have been recognized in connection with several diseases …


Use Of Toxicants For Coyote Control By Livestock Producers In Alberta, Michael J. Dorrance Mar 1980

Use Of Toxicants For Coyote Control By Livestock Producers In Alberta, Michael J. Dorrance

Vertebrate Pest Conference Proceedings: 9th (1980)

This paper examines and evaluates the use of strychnine baits and cyanide guns for coyote (Canis latrans) control by livestock producers in Alberta. Livestock predation occurred almost exclusively during spring, summer, and fall; livestock predation was negligible during winter. In contrast, use of toxicants was negligible in spring, distributed rather evenly through the summer and fall, and most intense in mid-winter. Forty-eight percent of the producers set toxicants in response to predation, and 1/2 of these apparently resolved their predator problems. Fifty-five percent of the producers set toxicants for preventive control, predominantly during October-February when the effectiveness of control was …


Socioeconomic And Ecological Aspects Of Field Rat Control In Tropical And Subtropical Countries, Hans Kurylas Mar 1980

Socioeconomic And Ecological Aspects Of Field Rat Control In Tropical And Subtropical Countries, Hans Kurylas

Vertebrate Pest Conference Proceedings: 9th (1980)

The vital question, as to the cause of the permanent increase in field rat populations throughout most tropical and subtropical areas, has been the subject of researchers and fieldmen during the past years, in the hope of finding an answer to this problem. Man has made his way through history wherein he was gradually able to renounce nature and establish his own man-made cultural frame. Unlike other mammals, man has no natural instincts to guide him through life. Brain and spirit have to compensate for lack of physical capabilities and instincts. Man was forced to change his natural surroundings in …


Baiting Blackbird And Starling Congregating Areas In Kentucky And Tennessee`, C.E. Knittle, J.L. Guarino, P.C. Nelson, R.W. Dehaven, D.J. Twedt Mar 1980

Baiting Blackbird And Starling Congregating Areas In Kentucky And Tennessee`, C.E. Knittle, J.L. Guarino, P.C. Nelson, R.W. Dehaven, D.J. Twedt

Vertebrate Pest Conference Proceedings: 9th (1980)

Four studies were conducted in January 1977-79 in Kentucky and Tennessee. Two of these studies were to determine the feasibility and effectiveness of selectively reducing starlings from mixed blackbird/starling winter roosts by baiting their congregating areas with Starlicide Complete pellets. The two remaining studies dealt with determining bait preference of starlings and nontarget birds for two formulations of pelleted baits (Layena and corn). Starlicide baitings were fairly selective for starlings, but nontarget hazards were encountered. Starlings showed no significant preference for either type of pelleted bait, but nontargets preferred corn over Layena pellets. Methods are suggested to minimize nontarget hazards …


Mammals And Birds Affecting Food Production And Storage In Nigeria, Oluwadare Funmilayo Mar 1980

Mammals And Birds Affecting Food Production And Storage In Nigeria, Oluwadare Funmilayo

Vertebrate Pest Conference Proceedings: 9th (1980)

The systematic study of the roles of vertebrate pests in agriculture in Nigeria is relatively very young, having spanned only two decades. During this period the species composition of vertebrate pests has been determined in some important crop plants like cocoa (Taylor 1961, Everard 1968), oil palm (Greaves 1964), maize (Everard 1966; Funmilayo 1976) and rice (Funmilayo and Akande 1977). The ecology of a few important pest species has been studied. Because of its devastating destruction of many graminaceous crops in Nigeria and over most parts of Africa, the red-billed quelea (Quelea quelea) has been studied more intensively than other …