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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.
481

Comparison of Variable Rate Prescriptions and Optimum Seeding Rate in Soybean [Glycine max (L.) Merr] and the Impact of Soybean Seeding Rate on Combine Fuel Use and Grain Loss at Harvest

Hamman, William Patrick 26 August 2019 (has links)
No description available.
482

A Comparison of Mixed Integer Programming and a Heuristic Approach for Harvest Blocking in Australia

Taylor, Ronald Gordon 07 May 2016 (has links)
The goal of harvest scheduling is to produce a practical operations schedule that can be implemented in the field by operational foresters and maximizes all values. The resulting harvest units need to represent a close approximation to what will be done operationally and while emulating natural disturbance regimes and topographic boundaries. using flow direction surfaces. Two methods of meeting spatially acceptable harvest units through a heuristic algorithm and a mixed integer programming method. A factor analysis was conducted on both to determine the statistical significance between 3 forest characterizations and mean financial and shape index indicators. Mixed integer programming had higher cash flows and net present values per hectare and the heuristic method had higher net present value per cubic meter at the 95% level of significance.
483

How Hunters’ Harvest Rate Varies in Response to Population Densities of Fallow Deer (Dama dama), Roe Deer (Capreolus capreolus), and Wild Boar (Sus scrofa)

Skorsdal, Felicia January 2022 (has links)
For many species, population size data is difficult to obtain or even unavailable. Therefore, estimations or indirect abundance measures of populations are crucial for ungulate management. Hunting has an important role in wildlife management, and is a partnership between state, landowners, and hunting communities. In ungulate management harvest statistics, as well as ungulate-vehicle collisions (UVCs) and observations, are often used as proxies for population densities and provide detailed information on a spatial and temporal scale. A Bayesian approach was used to model hunters’ response to population densities of fallow deer (Dama dama), roe deer (Capreolus capreolus), and wild boar (Sus scrofa). The results indicate that the variability in number of individuals observed and the non-linearity of both hunters’ harvest and UVCs response varies between roe deer, fallow deer, and wild boar. Both hunters’ harvest and UVC display a sub-linear response to population densities to all three species. Additionally, roe deer show a low variability in the number of individuals observed compared to the other two species. Predictions of population densities by using proxies like harvest statistics and UVC statistics need to be species-specific to be reliable, and by considering a potential sub-linearity and temporal trends for the species of interest more confident and realistic estimates can be developed.
484

Energialstring för drivande av smart enhet utan batterier : Design av ett energialstrande system för smart sko genom piezoelektronik och solceller / Energy harvesting to power smart unit without batteries : Design of an energy harvesting system implementing piezoelectronics and solar cells for a smart shoe

Rudd, Clive January 2019 (has links)
Projektet beskriver ett tillvägagångssätt för att alstra energi genom solceller och piezoelektronik. Ett kretskortsbaserat system designades som utnyttjade superkondensatorer som lagringsenhet. Planen var att integrera systemet i en sko. Genom denna teknik kan man då substituera eller minimera batteriladdningen för smarta enheter eller mindre anordningar. Det önskvärda resultatet med projektet var att se om det gick att koppla detta system till en mikrokontroller som kunde drivas på låg spänning. Rapporten fick ett positivt resultat med en konstant utspänning på 1.8 volt som kunde driva en mikrokontroller. Dock tog det lång tid för superkondensatorerna att laddas upp på grund av den impedans som fanns i systemet. Aktiviteter som utnyttjar detta system kommer att påverka uppladdningens resultat. Detta gör kretsen optimal för aktiviteter som involverar rörelse och sol, såsom hiking. / The past couple of decades gave rise to smartphones, smart watches, and smart homes. Now researchers are looking for ways to make smart clothing. One use case of smart clothing is smart shoes which can give some very useful sensed information especially in the sports industry and healthcare. Such sensed data include temperature, distance and calories, fall detection and many more. This application scenario can be designed to be battery free if we make use of the human motion and solar power. Many research papers exist which present how to exploit swing and shock excitations from the shoes to harvest energy. In this project this energy combined with solar energy will be used to power a low driven MCU. I design a pcb which include solar panels and piezoelectric modules to store the energy in supercapacitors. The goal is to integrate this pcb in a shoe, meaning that it has to have a small size and low power. The results of the project showed that a constant voltage at 1.8 volt could be achieved however recharge time is a factor to take into consideration. The system showed positive results for activities including movements and sun such as hiking.
485

<b>Measurements for TEG based Energy Harvesting for </b><b>EQS-HBC Body Nodes and </b><b>EM Emanations for Hardware Security</b>

Yi Xie (17683731) 20 December 2023 (has links)
<p dir="ltr">Sensing and communication circuits and systems are crucial components in various electronic devices and technologies. These systems are designed to acquire information from the surrounding environment through sensors, process that information, and facilitate communication between different devices or systems. It plays a vital role in modern electronic devices, enabling them to collect, process, and exchange information to perform various functions in applications such as IoB (Internet of Body), healthcare, hardware security, industrial automation, and more.</p><p dir="ltr">This work focuses on innovations in sensing and communication circuits spanning two independent application areas – human body communication and hardware emanations security.</p><p dir="ltr">First, an ultra-low power ECG monitoring system is implemented to perpetually power itself using Thermoelectric Generator (TEG) to harvest body energy while securely transmitting sensed data through on-body communication, achieving closed-loop operation without external charging or batteries. Custom circuits allow demonstrated feasibility of self-sustaining wearables leveraging Human Body Communication’s advantages.</p><p dir="ltr">Second, investigations reveal vulnerabilities introduced when repairing broken cables, with unintended monopole antennas boosting electromagnetic emissions containing signal correlations. Experiments characterize long-range detection regimes post-repair across USB keyboard cables. Further circuit and structural innovations provide localized shielding at repair points as a potential mitigation. Advancements offer contributions in understanding hardware emission security risks to inform protection strategies.</p><p dir="ltr">The two separate research work demonstrate specialized circuits advancing the state-of-the-art in sensing and communication for wearable body-based systems and hardware security through greater awareness of vulnerabilities from unintended emissions.</p><p><br></p>
486

Movements, relatedness and modeled genetic manipulation of white-tailed deer

Webb, Stephen Lance 11 December 2009 (has links)
White-tailed deer (Odocoileus virginianus) have been intensively studied across their range. However, many aspects of the white-tailed deer’s ecology have not been studied or are difficult to study. The advent of global positioning system (GPS) collar technology and molecular genetics techniques now allows researchers to collect fine-scale and cryptic phenomena. In addition, selective harvest of male white-tailed deer, based on antler size, has not been critically evaluated. Thus, development and use of quantitative genetics models will be useful for elucidating the effects of selective harvest on mean population antler size. I used GPS collar technology to further understand white-tailed deer movement ecology. First, I determined the efficacy and influence of a high-tensile electric fence (HTEF) on deer movements. The HTEF controlled deer movements when properly maintained and had little influence on deer spatial dynamics, making it a safe and cost-effective alternative to traditional fencing. Second, I studied fine-scale deer movements using GPS collars collecting locations every 15 minutes. Hourly deer movements were greatest in the morning and evening. Parturition and rut influenced movements of females and males, respectively whereas weather and moon phase had minimal influence on movements. Molecular genetics techniques are becoming more widespread and accessible, which may allow insight into the link between genetics and antler size. I found deer in 3 diverse populations from Mississippi, Oklahoma and Texas were relatively heterozygous and unrelated. Groups of deer with similar antler characteristics did not appear to be inbred or share common ancestors. In addition, there was not a strong link between individual multi-locus heterozygosity and antler points or score. Selective harvest has been implicated in causing negative evolutionary and biological responses in several ungulate species. To better determine how selective harvest (i.e., culling; the removal of deer with inferior antlers) affects white-tailed deer antler size, I used quantitative genetic models to simulate response of deer antlers to selection. In simulated controlled breeding situations response to selection was rapid, resulting in improvement in antler size. In simulated free-ranging populations response of antler size to selection was slow and only resulted in minimal increases in antler points after 20 years.
487

POPULATION LOSS OF GOLDENSEAL, HYDRASTIS CANADENSIS L., (RANUNCULACEAE), IN OHIO

Mulligan, Margaret R. 17 October 2003 (has links)
No description available.
488

Spatial Analyses of Northern Bobwhite Occupancy and White-tailed Deer Hunter Distribution and Success in Ohio

Sforza, Stephanie A. 22 July 2022 (has links)
No description available.
489

Chemical Compositions of Edamame Beans and Valorization of Edamame Shells

Yu, Dajun 23 January 2023 (has links)
Edamame is becoming more popular in the U.S. due to its high nutritional value and potential health benefits. However, more than 70% of edamame is imported from outside of the U.S. Therefore, developing elite edamame genotypes is critically desirable to increase the domestic production of edamame in the U.S. Genotype, planting location, and harvest time play essential roles in the chemical composition of edamame, which further decide edamame's nutritional value and sensory characteristics. Therefore, the first goal of this study is to comprehensively evaluate the chemical composition of edamame genotypes grown in different locations. Ten selected edamame genotypes were grown in three locations in the U.S. - Whitethorne, Virginia (VA), Little Rock, Arkansas (AR) and Painter, VA. Sugars, alanine, protein, oil, neutral detergent fiber (NDF), starch, ash, and moisture contents, were comprehensively analyzed. The results showed that location had significant effects on all chemical components of edamame with p < 0.05. Compared to Painter and Little Rock, genotypes planted in Whitethorne had higher averaged free sucrose, fructose, glucose, raffinose, stachyose, and starch contents and total sweetness. The highest crude protein and oil contents were found on edamame planted in Painter, while Little Rock produced edamame with the highest free alanine, ash, and moisture contents. Genotype significantly affected chemical compositions except for NDF and raffinose. Therefore, planting location and edamame genotype should be considered when producing elite edamame for the U.S. market. Chemical composition changes with the development of edamame; therefore, harvest time is essential for harvesting high-quality edamame. The second objective of this study is to quantify the changes in both physical and chemical properties of edamame over bean development and apply a combined spectroscopy and machine learning (ML) technique to help determine the optimal harvest time. Physical and chemical properties were analyzed for edamame harvested at R5 (beginning seed), R6 (full seed), and R7 (beginning maturity) growth stages, and the spectral reflectance (360 – 740 nm) of edamame pods was measured using a handheld spectrophotometer. The samples harvested at different stages were labeled as 'early,' 'ready,' and 'late.' At R6, pod/bean weight and pod thickness reached the peak and then stayed stable, while sugar, alanine, starch, and glycine also peaked at R6 but declined afterward. The spectra-based ML method had high accuracy (0.95) when classifying 'early' and 'late' edamame, and the accuracy was 0.87 for classifying 'early' and 'ready' edamame. These results indicated that this spectra-based ML method could determine the optimal harvest time of edamame. Food waste and loss not only lead to economic loss but also significant greenhouse gas emissions. With edamame food/snack production increasing, edamame shells, the low-value byproduct from this processing, will potentially threaten the environment. Similar to other food processing byproducts, edamame shell is rich in dietary fiber (DF). However, the high concentration of insoluble dietary fiber (IDF) limits its application as a food additive. Therefore, extraction/modification processes are needed to convert IDF to soluble dietary fiber (SDF) and improve the properties of edamame shell-derived DF. Ball milling is one of the most efficient techniques to break down biomaterials into sub-micro-level particles. Citric acid, as a natural and safe food additive, can help break down cell walls and improve the dissolution of SDF by ionizing the hydrogen ions with carboxyl groups. Therefore, the third objective of this study is to develop a process that combines ball milling and citric acid treatments to produce SDF from edamame shells. We investigated different treatment parameters, including different citric acid concentrations, treatment temperatures and time, and the application of ball milling. To determine if the combined treatment can potentially improve the properties of the produced SDFs, we characterized the physicochemical, morphological, structural, rheological, thermal, and functional properties of SDFs produced at different conditions. The results showed that the highest SDF yield (19.5%) was found when the edamame shells were pretreated by a ball mill. In addition, the combined citric acid and ball milling treatment altered several properties of the produced SDFs, including particle size, morphology, and crystallinity. Moreover, ball milling treatment led to a higher exothermic temperature peak of SDF indicating better thermal stability. All produced SDFs significantly elevated the production of short-chain fatty acids during in vitro fermentation (compared to the control fermentation) which indicated their potential benefits of promoting gut health. Overall, we demonstrated that ball-milling-assisted citric acid processing can be an effective green technique to produce SDF from edamame shells. The SDF produced from edamame shells can be regarded as a promising and novel ingredient with great potential to be used in foods. / Doctor of Philosophy / Edamame is becoming increasingly popular among consumers in the U.S. because it is nutritious and good for health. However, more than 70% of edamame in the U.S. market is imported from other countries. Therefore, having more edamame genotypes that adapt to the growing environment in the U.S. will help increase the domestic production of edamame. Genotype and planting location are essential in deciding edamame's nutritional value and taste. Therefore, the first objective of this study is to comprehensively understand the nutritional value of different edamame genotypes grown in three planting locations. The results showed that both location and genotype affected the nutritional values of edamame, indicating that planting location and edamame genotype should be considered when developing better edamame for the U.S. market. Nutritional value and sweetness change with the growth of edamame beans. Therefore, harvest time is crucial for harvesting edamame with better nutrition and taste. This study's second objective is to observe edamame's nutritional factors and sweetness over bean development and develop a method using a handheld colorimeter to help determine the optimal harvest time. The results showed that the edamame harvested at the full seed stage (called R6) is the sweetest compared to the other two stages. In addition, the handheld colorimeter combined with the machine learning technique showed high accuracy in separating 'early' and 'late' harvested edamame and 'early' and 'ready' harvested samples. These results indicated that the combination of colorimeter and machine learning could help determine the optimal harvest time of edamame. Food waste and loss not only lead to economic loss but also significant greenhouse gas emissions. Edamame shells, the low-value byproduct from edamame snack/food processing, will potentially threaten the environment if edamame consumption keeps increasing. Like other food waste, edamame shell is rich in dietary fiber (DF). Therefore, it is vital to find a way to recover the DF in edamame for other applications. Ball milling is a green technology that can efficiently break down big particles. Citric acid is a natural and safe food additive and can help break down insoluble cell walls. Therefore, this study aims to produce soluble dietary fiber (SDF) from edamame shells using ball milling and citric acid. We proved that ball-milling assisted acid processing can be an environmentally friendly method to produce edamame shell SDF which can potentially be used as a suitable food ingredient.
490

Spatial Ecology of Bobcats (Lynx rufus) in the Appalachian Mountains of Western Virginia

McNitt, David C. 27 August 2019 (has links)
Despite the prevalent distribution of bobcats in western Virginia and the broader region of Appalachia, there is a paucity of information on their spatial ecology in this region. Due to the unique ecological conditions of Appalachia, and increasing public interest surrounding the role of bobcats as predators in the region, there is a need for local information on bobcat ecology. I utilized data from 20 GPS collared bobcats (14M, 6F) to investigate bobcat spatial ecology in the mountains of Western Virginia. Average resident male home range size was 33.9 ± 2.6 km^2, nearly 3 times larger than average resident female home range size (12.1 ± 2.4 km^2). Seasonal areas of use did not differ in size among seasons, but exhibited minor shifts in location and shape. Average male movement rates (232.3 ± 12.0 meters/hour) were 1.5 times greater than average female movement rates (154.4 ± 8.9 meters/hour). Male movement rates increased during the dispersal season and female movement rates increased during the denning/kitten-rearing season. Second order resource selection analysis indicates that bobcats of both sexes select home ranges at higher elevations than expected at random, and that selection varies between sexes and among seasons. Third order resource selection analysis indicates that bobcats select for locations near open canopy structure, and avoid forest interior. These findings build upon previous findings regarding bobcat diet and population dynamics to provide a comprehensive understanding of basic bobcat ecology in western Virginia, and will inform further research investigating predator/prey interactions. / Master of Science / Despite the prevalent distribution of bobcats in western Virginia and the broader region of Appalachia, there is a paucity of information on their spatial ecology in this region. Due to the unique ecological conditions of Appalachia, and increasing public interest surrounding the role of bobcats as predators in the region, there is a need for local information on bobcat ecology. I utilized data from 20 GPS collared bobcats (14M, 6F) to investigate bobcat spatial ecology in the mountains of Western Virginia. I found that male bobcats use more space than females, with home ranges nearly 3 times larger and movement rates 1.5 times higher. I found that home ranges do not expand or contract throughout the year, but do shift in shape slightly. I found that bobcats select home ranges at higher elevations, indicating that home ranges are predominantly located on ridges. I found that selection of home ranges differed between sexes and seasons, indicating that shifts in home range shape throughout the year reflect varying habitat selection. Within their home ranges, I found that bobcats select for areas of open canopy resulting from fields, fire, and timber harvest; and avoid areas of forest interior. These findings build upon previous findings regarding bobcat diet and population dynamics to provide a comprehensive understanding of basic bobcat ecology in western Virginia, and will inform further research investigating predator/prey interactions.

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