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The Role Of Agriculture In South Dakota's Economy : An Approach To Analysis, Mahlon George Lang Mar 1972

The Role Of Agriculture In South Dakota's Economy : An Approach To Analysis, Mahlon George Lang

Electronic Theses and Dissertations

Dependency of the state's economy upon the agricultural sector demands that economic research and public policy with respect to agriculture be based upon a more refined understanding of the magnitude and nature of the relationship between the farm and nonfarm economies. Ideally, the earliest stages of decision-making in government grow out of carefully developed research into the likely outcomes of alternative public policy decisions. At the macroeconomic level, such research requires a firm grasp of the complex chain of events which will occur as a result of changes in policy toward agriculture. At present, this chain of events is only …

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The Scheduling Of Patients In A Physician's Office, Viswanath Gowtham Mar 1972

The Scheduling Of Patients In A Physician's Office, Viswanath Gowtham

Electronic Theses and Dissertations

The objective of this investigation was to design a procedure by which an appointment scheduling system could be developed in which 75 percent of the punctual patients would be seen by the physician within fifteen minutes of their appointment tithes, and to test the system in an actual clinic situation. It was also decided that certain results would be tested for statistical significance. To devise an appointment system that would yield optimum benefits to the patients, to the physicians, and to the clinic as a whole, proper consideration must be given to the type of physician/patient interaction taking place in …

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A Study Of An Innovative Program Designed To Aid In Meeting The Needs Of Disadvantaged Students In Florence, South Carolina, Theodore Howard Gasper, Jr. Mar 1972

A Study Of An Innovative Program Designed To Aid In Meeting The Needs Of Disadvantaged Students In Florence, South Carolina, Theodore Howard Gasper, Jr.

Electronic Theses and Dissertations

In many instances, students fail to adjust to the regular school situation and consequently drop out. To counteract this, Florence Public School District Number One, instituted a program titled "Special Vocational Education”, which is an attempt to meet the needs or what is termed the "disadvantaged students." This study is of utmost importance in that it is an investigation to determine whether or not this special program is keeping the majority of the enrolled disadvantaged students in school. It is also important to know the amount of growth in academic skills and social traits made by the students each year. …

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Operation Of Induction Motor Open-Delta Transformer Banks, Gautam C. Das Mar 1972

Operation Of Induction Motor Open-Delta Transformer Banks, Gautam C. Das

Electronic Theses and Dissertations

Induction motors and transformers are among the earliest electrical equipment to be manufactured. The squirrel-cage induction motor has been studied very widely from the time of Tesla and Ferraris in 1889. The operation of a squirrel-cage induction motor with an unbalanced supply voltage has also been studied in great detail. Yet there is little mention of an induction motor operating on an open-delta or vee-connected transformer bank in textbooks. The open-delta transformer connection is the equivalent of the delta-delta connection with one transformer removed. The vee-connection is equivalent to a star-delta connection with one transformer removed; the primary neutral must …

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Digital Solution Of Power-Flow Problems By Newton's Method Of Using A Hybrid Matrix, Prem K. Bahl Feb 1972

Digital Solution Of Power-Flow Problems By Newton's Method Of Using A Hybrid Matrix, Prem K. Bahl

Electronic Theses and Dissertations

The last decade and a half has witnessed dramatic developments in the application of digital computers for solving power-flow problems. Previously these problems were analyzed on the direct analog computers called a-c calculating boards. With the enormous growth of the interconnected power systems during this period of time, digital computers established a distinct advantage over the analog computers for such reasons as: (a) Their ability to analyze large-size systems (with such features as automatic tap setting, automatic area interchange control, and control of reactive constraints of generators). (b) Elimination of human error in reading data and recording information on the …

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Parameters Of The Super-Beta Transistor, Ho-An Au Feb 1972

Parameters Of The Super-Beta Transistor, Ho-An Au

Electronic Theses and Dissertations

Transistors with current gains of 1,000 to 10,000 at collector current levels as low as 1 µA can now be made in discrete and in monolithic form. These devices are generally called super-beta or super-gain transistors. It is well-known that a narrow base width results in a high-beta transistor. As the emitter is diffused more deeply into the base, reducing the base width, the current gain will increase. But there is a trade-off between breakdown voltage and current gain. When the emitter is deeply diffused, the depletion region of the collector-base junction may penetrate the base and reach through to …

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An Arab Perspective On The Rubaiyyat Of Omar Khayyam, Elias Agel Feb 1972

An Arab Perspective On The Rubaiyyat Of Omar Khayyam, Elias Agel

Electronic Theses and Dissertations

Since this study is concerned with a comparative study of the Rubaiyyat in both Arabic and English poetry, and since the main purpose is to arrive at some understanding of the Rubaiyyat through a knowledge of the Islamic literature, it is essential here to give a short introductory note of some technical terms and facts about the Arabic language and Arabic poetry in particular. In general, there is a great difference between the structure of Semitic languages and Indo-European languages, and hence between English and Arabic. The most characteristic feature of the Arabic language is that the great majority of …

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Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa Jan 1972

Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa

Electronic Theses and Dissertations

The use of Waterfowl Production Areas (WPA) by American coots (Fulica americana) and ducks was studied during 1970 and 1971 in east-central South Dakota The Eriksrud WPA, a type IV wetland with 55 acres of water area and 35 acres of upland, contained 188 coot nests during the 2-year study. Of the 188 coot nests, 178 hatched for a success rate of 95 percent. Average clutch size of 130 completed clutches was 8.4. Average size of 21 coot broods from 4 to 6 weeks of age was 6.1. Coot production on the Eriksrud area was estimated at 543 young per …

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Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson Jan 1972

Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson

Electronic Theses and Dissertations

Sudan Red IV, Sudan Black B, and demethylchlortetracycline (DMCT) were tested as physiological markers in baits for raccoon (Procyon lotor). DMCT was readily detected in the jawbone of raccoons given 50 mg when examined under an ultraviolet light at period of 7, 30, 75, and 450 days following treatment. Seven days after administering 75 mg of Sudan Red IV, it could not be detected in fat deposits. Sudan Black B, administered in similar dosage, could not be detected at 30 days. A total of 1826 chicken eggs containing 50 mg DMCT was distributed on a 25 square-mile study area between …

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Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys Jan 1972

Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys

Electronic Theses and Dissertations

The food habits of young-of-the-year, subadult and adult black bullheads were studied in Lake Poinsett, South Dakota, from March, 1970, to April, 1971. Two hundred twenty young-of-the-year (37-87 mm total length) fed primarily on limnetic cladocerans and copepods. Leptodora and Diaphanosoma comprised 86.5% of the total food volume. Chironomid larvae and pupae made up 5.6% of the total. Other benthic organisms and littoral cladocerans together contributed less than 1%. Stomach contents of 608 subadult and adult black bullhead (143-304 mm total length) indicated significant seasonal vairaiton in diet. Daphnia pulex and chronomid larvae were important food items in winter. Bullheads …

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Influence Of Weather On Movement And Habitat Use Of Hen Pheasants During Brood Rearing, James M. Ruth Jan 1972

Influence Of Weather On Movement And Habitat Use Of Hen Pheasants During Brood Rearing, James M. Ruth

Electronic Theses and Dissertations

Pheasants survive in a wide range of yearly weather extremes but can be limited by certain short-term weather factors (Graham and Hosterburg 1948). Study of short-term weather conditions can therefore be important in understanding pheasant survival. Many studies have been done on yearly and seasonal effects of weather on pheasant production and survival. Bemitt and Terril (1940) reported on possible temperature factors in pheasant management in the north central area of the United States. Effects of weather on pheasant reproduction were studied by Buss and Swanson (1950) and Kozieky et al. (1955). MacKullan and Eherhardt (1953) studied the tolerance of …

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Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke Jan 1972

Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke

Electronic Theses and Dissertations

Food habits of yellow perch, bluegill, and black crappie were studied during 1970 and 1971 in Abbey Pond, South Dakota. Aquatic insects, zooplankton, mollusks, and fish were the most frequently consumed food items by the three species. Yellow perch led primarily on aquatic insects, zooplankton, and mollusks. Aquatic insects were dominant (by volume) in 40.0 and 61.5 percent of the samples respectively for the two years. Zooplankton, mollusks, aquatic insects, and bryozoans were the dominant food items by volume of adult bluegills. On an annual basis aquatic insects were the most important food item in the diet. Adult black crappies …

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Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler Jan 1972

Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler

Electronic Theses and Dissertations

A study of waterfowl production was conducted on two study areas in the James River Valley of South Dakota in 1971 and 1972. Its objectives were to measure rates of reproductive success and to determine the effect of land use and other influences on duck production. The five most abundant species of nesting ducks were blue-winged teal (Anas discors), mallard (platyrhvnchos), gadwall (A. strepera), shoveler (clypeata), and pintail (acuta). Seventy-two percent of the wetland habitat on the study areas consisted of temporary (Type l and Type 3) water areas. Only 3.9 percent of the wetlands represented semi-permanent (Type 4) and …

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Experimental Study On Viscoelastic Properties And Fracture Characteristics In Polymers, Debaranjan Mohanty Jan 1972

Experimental Study On Viscoelastic Properties And Fracture Characteristics In Polymers, Debaranjan Mohanty

Electronic Theses and Dissertations

The research reported in this thesis is undertaken with the following objectives:
1. To determine the viscoelastic properties of polymers on creep test under constant load;
2. To determine the internal friction (loss factor) of polymers under periodic loading condition;
3. To determine the delayed time or life time on fracture of the polymer under constant loading ; and
4. To verify the relationship, theoretically predicted, between the time to fracture and the material characteristics of the polymer with experimental observations.

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One Way Of Stabilizing A Bipedal Walking Machine, Gerald Paul Berger Jan 1972

One Way Of Stabilizing A Bipedal Walking Machine, Gerald Paul Berger

Electronic Theses and Dissertations

A feedback control system for a bipedal walking machine model given in previous study is presented and analyzed. The bipedal model is first simplified and then equations of motion are derived. Criteria for stability are chosen and different control systems are briefly considered. In the survey of control systems available, it is shown that the sampled-data control system with a large sampling period has some advantages in the practical realization. Such a sampled-data feedback control is analyzed in some detail to determine its control potential. The sampled-data control system analyzed uses a predictive analog control algorithm. The analysis of the …

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Similitude Study Of Airflow Characteristics And Evaluation Of Ridge Vent Design For An Open Front Confinement Beef Barn, Ivar R. Dybwad Jan 1972

Similitude Study Of Airflow Characteristics And Evaluation Of Ridge Vent Design For An Open Front Confinement Beef Barn, Ivar R. Dybwad

Electronic Theses and Dissertations

Predictions for the future indicate that beef cattle production will continue to increase. The U. S. Department of Agriculture has estimated that the demand for red meat would increase by over 60 per cent between 1958 and 1975. Beef consumption in the United States is 80 to 85 pounds per capita per year. However, some light meat, turkey and chicken will be substituted for red meat, but due to the continuing increase in human population, the production of beef will have to increase to meet the domestic need. Following the trend of the last few years, more beef cattle production …

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A Study Of Selected Factors Associated With Environmental Attitudes Of Big Stone Lake Area Residents, Bradford George Perry Jan 1972

A Study Of Selected Factors Associated With Environmental Attitudes Of Big Stone Lake Area Residents, Bradford George Perry

Electronic Theses and Dissertations

A study of Big Stone Lake area residents was accomplished to aid in determining the following: (1) The existing attitudinal orientations of area residents relative to an incoming electrical generating facility (the Big Stone Power Plant); (2) The degree of association between selected variables and respondents' environmental attitudes; (3) The capability of the areas existing institutions to accommodate the local population, and possible effects of plant construction and operation; (4) The potential reference groups utilized for behavioral orientation. The unit of analysis consisted of Big Stone Lake area residents within a three county universe of discourse. Primary emphasis in sampling …

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An Incrementally Distributed Mathematical Model Of A Watershed, Charles Arnold Onstad Jan 1972

An Incrementally Distributed Mathematical Model Of A Watershed, Charles Arnold Onstad

Electronic Theses and Dissertations

The utilization of distributed input parameters enables hydrologists to more adequately cope with watershed management problems. A distributed system aids in evaluating alternative solutions designed to alleviate a problem situation. As a result, the objectives of this study were (1) to develop a hydrological framework delineating the surf ace configuration of a watershed to consider parameter distribution; (2) to develop a model of hydrologic performance of a watershed using existing techniques and amenable to the physical framework; and (3) to demonstrate the versatility of the model using hypothetical data. The model versatility was demonstrated by showing the effects of different …

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On The Problem Of An Infinite Number Of Non-Coplanar Parallel Cracks In A Strip With Constrained Edges, Dana F. Peterson Jan 1972

On The Problem Of An Infinite Number Of Non-Coplanar Parallel Cracks In A Strip With Constrained Edges, Dana F. Peterson

Electronic Theses and Dissertations

No abstract provided.

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The Poisson Distribution And Some Of Its Applications, Marshall Glenn Duckworth Jan 1972

The Poisson Distribution And Some Of Its Applications, Marshall Glenn Duckworth

Electronic Theses and Dissertations

No abstract provided.

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Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren Jan 1972

Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren

Electronic Theses and Dissertations

In 1970 and 1971, cock pheasants (Phasianus colchicus) were given single capsules weekly containing 0 and 25 mg polychlorinated biphenyls (PCB), Aroclor 1254, and hens were given O, 12.5, and 50 mg. Egg production was reduced (P<0.01) in the hens given 50 mg PCB both years. Fertility, determined by visual inspection of incubated eggs, was unaffected by PCB. Hatchability was lowest in the group of hens given 50 mg in both years but significantly lower (P<0.01) only in 1971. PCB adversely affected the viability of the embryo both years, as the number of eggs pipped but not hatched in PCB groups was higher (P<0.05). PCB did not affect eggshell thickness. Behavior on the visual cliff shortly after hatching was affected among offspring of hens given 50 mg PCB in 1970 (P,0.01). Offspring of hens given 50 mg chose the visually-deep side of the cliff. No differences in behavior on the visual cliff were evident in 1971. Response to hand catching of offspring was affected in 1970 (P <0.01). The ability of penned pheasants to avoid hand capture was least where both parents received PCB, followed by those where hens only, cocks only and neither parent received PCB. No differences in response to hand capture among groups were found in 1971. Weights of chicks from hens on 50 mg were lower (P<0.01) at 6 weeks of age in 1970. This effect was not seen in 1971. Survival of chicks in brooders to 6 weeks of age was lower (P<0.01) in offspring of hens given 50 mg PCB weekly in 1970. No differences were found among offspring of treatment groups in 1971. Survival from 6 weeks of age to fall was similar in all groups. Overall survival from hatching to fall was less (P<.0.05) in offspring of hens given 50 mg weekly in both years combined. No differential effect was found between sexes for survival. PCB in doses varying front 10 mg to 210 mg daily caused hyper-excitability, weakness, tremoring, lack of appetite, lack of feathers, and a comatose death. Birds 11-weeks old given 10 or 20 mg PCB daily, birds 6 to 9 months old given 50 or 100 mg each 3.5 days, and adult hens given up to 50 mg once a week continued to eat. Eleven-week old birds given 210 mg daily stopped eating or those given 210 mg daily, the heaviest birds lost the greatest percentage of their weight (15 to 31 percent) before death occurred (1.3 to 4.3 days). Birds intentionally starved at the same time lost a greater percentage of weight (27 to 51 percent) before death (2.3 to 8.6 days). Some adult hens were given a single 50-mg capsule and samples of whole body, brain, liver, muscle, eggs, and feces were analyzed to determine patterns of storage and excretion. Levels of PCB were highest at 12 hours after capsule administration. Residues were highest in liver, followed by brain and muscle over 28 days following the single 50-mg capsule. From 94 to 98 percent of the administered dose was absorbed and 40.5 mg of the 50mg were in the body after 28 days. Hens were in a state of low egg production and excreted 4.2 mg in the eggs and 4.0 mg in the feces over 28 days. Excretion in the egg could be an important means of ridding the body of PCB. Four hens from the 1970 breeding experiment, given 17 capsules weekly containing 12.5 mg PCB and killed 1 week following the last capsule, had from 37 to 56 percent of the administered dose in their bodies. Four hens on the 50-mg level in 1970 had from 60 to 82 percent of the dose given. Five hens given 12.5 mg weekly for 16 weeks in 1971 had an average of 23.8 ppm PCB in their bodies 1 week after the last capsule, three hens had an average of 13.6 ppm after 3months on a clean diet, and three others had an average of 20.9 ppm after 6 months. Excretion was variable and slow. An analysis of brain, liver, and muscle tissues from dead and surviving birds fed PCB at various levels showed that brain residue levels from 300 to 400 ppm wet weight were indicative of death from FCB toxicosis. Liver and muscle levels were too variable to be useful in assessing cause of death. Administration of PCB decreased weights of heart and spleen (P <0. 01) at all levels given and increased weights of kidneys and livers in birds given 10- and 20-rng doses daily (P <0. 01) but not in birds given 210 mg daily. Splenic atrophy, where spleens were small, pale-tan color, and had wrinkled capsules resulting from depletion of lymphatic nodules, was characteristic of birds given PCB. PCB and dieldrin were given singly and jointly, and only additive, not synergistic, effects were noted. Livers of wild pheasants from Pennsylvania, Indiana, and South Dakota had no more than 2 ppm PCB. This indicates low-level contamination.

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Cooling Load Calculations Of Heat Gain For Buildings, Hai- Chow Chen Jan 1972

Cooling Load Calculations Of Heat Gain For Buildings, Hai- Chow Chen

Electronic Theses and Dissertations

Two recent papers [1,2] obtain formulas for temperature variations caused by the varying flow of solar heat through windows. These two works are used in the present study to develop a computer program for calculating the transient cooling load required to maintain the interior of a building at a given temperature. We assume that the building is standing by itself without surrounding radiating buildings or pavements. The heat gain through semi-transparent single or composite barriers is combined with the accompanying heat gain through the opaque walls; see Figure 1. The analytical solutions given in [1,2] cannot be represented directly as …

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A College Characteristics Instrument Measure Of Absolute Change Between Freshman Expectations And Perceptions Of A College Environment As Related To Grade Point Average And Sex Of The Student, Zdzislaw Piotrowski Jan 1972

A College Characteristics Instrument Measure Of Absolute Change Between Freshman Expectations And Perceptions Of A College Environment As Related To Grade Point Average And Sex Of The Student, Zdzislaw Piotrowski

Electronic Theses and Dissertations

The general thesis underlying this study is that a student's absolute change between expectations and perceptions of a college environment is related to his performance and sex. Two null hypotheses were generated. The hypotheses as related to the methodology and the CCI instrument of the study were: 1. There are no significant differences in the freshman change or C-score on the basis of sex of the student. 2. There are no significant differences in the freshman change or C-score on the basis of grade point average grouping. The population was divided into three groups with male and female subdivided within …

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The Role Of Rainfall Impact And Surface Flow In Soil Detachment And Transport, Robert Alan Young Jan 1972

The Role Of Rainfall Impact And Surface Flow In Soil Detachment And Transport, Robert Alan Young

Electronic Theses and Dissertations

Soil erosion caused by rainfall is a very complex physical process. To evaluate the mechanism of erosion so that an assessment can be made of the extent to which it may be controlled necessarily begins with an understanding of the basic fundamental factors involved. The purpose of this study involves the development of an insight of the relative importance of the roles played by various contributors to the erosion process. Particular emphasis is placed on the contribution of rainfall detached soil to total soil loss. Three soil types, Barnes loam, Crofton silt loam and Central sandy loam, were prepared with …

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A Simulation Of Sediment Deposit In Open Channels, Tsan-Wen Wang Jan 1972

A Simulation Of Sediment Deposit In Open Channels, Tsan-Wen Wang

Electronic Theses and Dissertations

In this study, two mathematical models have been developed to simulate sediment deposition in open-channel flow; a model based on three characteristic equations and a model based on two characteristic equations. A set of three partial differential equations for one dimensional transient flow with homogeneous density was provided to explain the mechanics of the phenomenon. By the method of characteristics, three partial differential equations were transformed into a set of three ordinary differential equations or a set of two ordinary differential equations by simplification in which the change of sediment layer thickness with respect to distance was assumed to be …

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The Distribution Of Primitive Roots In Fields Of Order P², Marilyn Sol Gerjets Jan 1972

The Distribution Of Primitive Roots In Fields Of Order P², Marilyn Sol Gerjets

Electronic Theses and Dissertations

Throughout this paper, small case Latin letters, with the exception of i which has its usual mathematical meaning, will denote rational integers where we let Z represent the set of all rational integers. We call µ = a + bi a Gaussian integer iff a and b are rational integers and we denote the set of all Gaussian integers by Z(i). The set of Gaussian integers can be represented geometrically by ·the set of lattice points in a Cartesian coordinate system whose horizontal and vertical grid lines are one unit apart. Since µ = a + bi is a complex …

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An Experimental Study Of No-Screen Bump Exposures For Short Density Range Reflection Copy, Stephen E. Horwood Jan 1972

An Experimental Study Of No-Screen Bump Exposures For Short Density Range Reflection Copy, Stephen E. Horwood

Electronic Theses and Dissertations

The purpose of this thesis, therefore, is to investigate a system of no-screen bump or highlight exposure (so-called because it is the highlight area of the negative that is affected) based on logarithmic densities and opacity tables. The system under investigation used in shooting the copy. R. E. Maurer says that 11 a contact screen is a light modulator that is placed in contact with the halftone emulsion. The small, vignetted dots in the photographic screen absorb the exposing light selectively so that the proper intensity distribution is produced in the halftone emulsion." The second exposure is the flash, which …

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Pheasant Production Using Wild Cocks And Penned Game-Farm Hens, Michael R. Grode Jan 1972

Pheasant Production Using Wild Cocks And Penned Game-Farm Hens, Michael R. Grode

Electronic Theses and Dissertations

Pheasant production using free-flying wild cooks and penned game-farm hens was evaluated during 1971. Hens were placed in 0.5-acre pens to compare production at density levels of 10, 20, and 40 hens per acre. Wild cooks entered the 0.5-acre pens the day following introduction of the game-farm hens. The greatest numbers of cooks were observed in the pens with the highest density of hens. Censusing in mid-March indicated a population of 12 to 15 wild cooks in the vicinity of the study pens. A known mortality of 31 hens occurred and percentage mortality was similar at each density level. Pulling …

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Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag Jan 1972

Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag

Electronic Theses and Dissertations

The ring-necked pheasant (Phasianus colchicus) is an important game bird, and various management techniques have been implemented in its behalf. One of the most common practices has been transplanting or stocking wherein pheasants are introduced into an area with a depleted population in hopes of increasing pheasant production. The effects of such programs are difficult to evaluate since there is no way of knowing if the introduced birds are in any way responsible for production changes which subsequently occur. If the taxonomic characteristics of the native and the introduced populations could be determined, the effect that introduced birds have on …

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Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer Jan 1972

Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer

Electronic Theses and Dissertations

Research was conducted in southwestern South Dakota in 1970 and 1971 to obtain information on the reproductive cycle of the black-tailed prairie dog (Cynomys ludovicianus) and to test effectiveness of diethylstilbestrol as a reproductive inhibitor. Embryo body lengths from 10 pregnant females were compared to body lengths of 14 known day-old young to learn the peak breeding period when an estrogenic chemosterilant would be most effective. Conception dates were obtained for three females by backdating the gestation period. The breeding peak was found to occur in late February and early March in South Dakota. Nine of 11 Prairie dogs were …

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