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Demographics of Adjacent Blanding\u27s Turtle (Emydoidea Blandingii) Populations in Central Michigan
No full textMany species of turtle are facing serious declines from multiple anthropogenic causes. One such turtle native to the United States, the Blanding’s Turtle (Emydoidea blandingii), has faced declines in nearly every sector of their range, yet few populations have known recorded demographics, such as abundance, density, sex ratio, and body sizes. To inform managers of these crucial demographic measures of three spatially adjacent populations on Camp Grayling, MI, I implemented a capturemark-recapture study from 2021 to 2022. I calculated Lincoln-Petersen Index and ran constant, time-varying, and behavioral response models for both full and conditional likelihoods in Program MARK. All best fit models estimated populations ≥30. The three populations sampled at Camp Grayling were low in abundance, densities, and biomass compared to some more well-known populations. Adult body weight means were 1456 g and 1223 g for males and females, respectively. Mean carapace lengths for males was 22.42 cm and females were 20.11 cm. The males of these populations were significantly larger than the mean found across the Blanding’ Turtles range. There is evidence of recruitment within these populations. A long-term research plan should be implemented and focus on investigating connectedness of these populations, as well as building data for population viability analyses. Additionally, immediate conservation action should take place to protect this vulnerable species
An Improved Out-Of-band 90° Branch-Line Coupler Design with Application to Butler Beamforming Network
No full textThis thesis introduces a 2.4 GHz hybrid 3-dB coupler with improved out-of-band rejection by incorporating a setup of transverse transmission lines, extensions, and open-circuit stubs at each of the coupler branches. To achieve matching at the design frequency, the ABCDmatrix of the above-mentioned setup is calculated and associated to that of a 90° transmission line, leading to exact analytical equations for the impedances and electrical lengths. Simulated coupler design shows a return loss and isolation better than –27 dB as well as an in-band and out-of-band transmission losses better than –4 dB and –25 dB, respectively.The resulting design is applied to a 4×4 Butler matrix, which consists of other components; namely, crossovers, phase shifters and phase matchers. After designing and validating each of these components, they are integrated in the Butler matrix. To validate the radiation (i.e., beamforming) patterns, a microstrip patch antenna array is also designed and verified. The overall network (i.e., Butler matrix, antenna array) is simulated and parameters including phase-differences and 2D and 3D radiation patterns are validated. These electrical parameters are also measured for the fabricated Butler matrix. Based on the 2D and 3D radiation patterns, beamforming is obtained at ±10° and ±30°.Beamforming has applications in many different areas. Some applications like tracking and localization, satellite communication, high power beam-steering, and harmonic radar are also referenced in this thesis.Finally, appendices are provided with further technical details of the simulations and measurements of the different components used in this work
Impact of lubricant in the performance of variable speed heat pumps working with R290
Get PDFModulating the speed of the compressors and adapting its capacity to the required load has led to a decrease in the annual energy consumption in many applications. However, in the compressor, having adequate lubrication at low speeds usually implies discharging too much lubricant at higher speeds. Although necessary for compressor operation, lubricating oil acts as a contaminant in the rest of the system. Consequently, manufacturers have to consider the oil circulation rate (OCR), as it limits the speed range of the compressor. In a previous study, a compressor was tested over its speed range (30 – 110 Hz), working with R290 and POE68 as a lubricant. Experimental data confirm the increase of OCR with speed and suggests that working with R290-POE68 could imply higher OCR values compared to other refrigerant-oil mixtures. In this study, the impact of the OCR in the performance of a R290 heat pump was theoretically assessed. Three contributions were studied: The heat transfer coefficient (HTC) reduction in the evaporator, the effect of refrigerant being solved in oil and finally, and the impact of oil in the compressor. It was found that OCR values of 5% could decrease the coefficient of performance (COP) by more than 20%
SPIRaL: Student Partners for Information Research and Literacy Undergraduate Research Program
Get PDFThrown into the World, Attached to Love: On the Forms of World-Sharing and Mourning in Heidegger
Get PDFHow can we understand the phenomena of loss and mourning in the Heideggerian framework? There is no established interpretation of Heidegger that gives an elaborate account of the phenomena of loss and mourning, let alone gauges its importance for our understanding and assessment of authentic existence in Heidegger. This paper attempts to do both. First, I give a detailed exposition of Heidegger’s analysis of the phenomena of mourning and loss and show that Heidegger’s analysis of mourning in his early and late work is strikingly in line with his collectivist understanding of Being-with. This demonstrates, contrary to what some of his proponents argue, that Heidegger does not follow the kind of dynamic understanding of Being-with that places the other within fine-grained spaces of possibility. Second, with reference to Heidegger’s existential philosophy, I construct a phenomenology of mourning and grief. Though Heidegger himself fails to explain the relationships in which one mourns after a close other, we can develop a unique phenomenology of mourning with reference to Heidegger, which shows that each loss is singular and can be equiprimordial with one’s own death in opening one to the possibility of an authentic existence. In this new understanding of authenticity, loss is regarded as a powerful force, akin to death, in leading one toward their self-owned existence
Approach to Problem Solving and Use of Intuition by Engineering Technology Students
Get PDFEngineering technology students often forgo a methodical approach of solving or answering questions on assignments or exams in favor of an intuition-based approach, emphasizing educated guessing (Broberg et al., 2008). Faculty observations have noted these student solutions often provide explanations, usually sans calculations, to support answers the students believe to be reasonable when in reality deviated from the correct answer. An extensive study was developed to assess several distinctions between student intuition and use of cognition in problem solving, as related to a generalized student population. The study was comprised of a survey and interview. The survey utilized two instruments, the Types of Intuition Scale (TIntS) and the Cognitive-Experiential Self Theory (CEST). The interview element was comprised of questions related to the student’s background and personal experience with math phobia. Data provided by study participants responding to specific questions from the TIntS and CEST instruments allowed researchers to determine how likely students are to use intuition rather than analytical processes. The results of the study found these students prefer to approach problems using logic but tend to rely upon their intuition when problem solving, especially in unfamiliar and high-pressure scenarios. Furthermore, this paper is intended to enlighten educators and other related groups regarding the degree to which intuition is used as a means of solving problems, and the types of intuition generally involved, especially for engineering technology students. Thus, providing practitioners and administrators with a better idea of what these students may provide in response to homework or other problem-solving situations
On the design and power output response of hydraulic wind turbines
No full textStandard horizontal axis wind turbines typically use gearboxes for large-scale applications and direct coupling for small-scale designs to connect the rotor to the generator. However, gearboxes pose challenges due to their weight, cost, and exposure to dynamic loads and vibrations within the nacelle. A promising alternative is replacing mechanical transmission with a hydrostatic counterpart, offering advantages such as reduced nacelle mass, generator placement at the tower base, and elimination of the gearbox. It can potentially lead to cost savings of up to 20% in the levelized cost of electricity for offshore wind turbines. This study compares regulated hydrostatic transmission with unregulated transmission and damping components under different wind conditions, including atmospheric boundary layer and low-level jet inputs. Dynamic simulations of a horizontal axis wind turbine incorporating a hydrostatic transmission are conducted to evaluate its response to wind fluctuations caused by prevailing wind velocity profiles, atmospheric boundary layer, and low-level jet velocity profiles. Addressing torque fluctuations and power impact on power quality and mechanical components is crucial in wind turbine operation. The proposed hydrostatic transmission includes primary and secondary proportional controllers for adaptability to varying wind speeds, along with integrated accumulators in the high and low-pressure lines. The main findings indicate that the regulated hydrostatic transmission achieves an efficiency range of 69%–75% across various wind velocity profiles, surpassing the unregulated counterpart. It reduces torque fluctuation amplitude by 35% and improves efficiency by nearly 20% compared to the basic transmission. Torque and power fluctuations are also reduced by 35% and 40%. These improvements are attributed to the damping capabilities of the hydrostatic transmission and the actions of the proportional controller. Implementing the regulated hydrostatic transmission offers several technical and economic advantages, including relocating the generator to ground level and achieving continuous hydraulic variable transmissions without the need for a gearbox. The methodology is applicable to a range of wind turbine sizes
Quantitative Methods for Analyzing Second Language Lexical Tone Production
No full textThe production of L2 lexical tone has proven difficult for learners of tonal languages, leading to the testing of different tone training techniques. To test the validity of these techniques, it is first necessary to capture the differences between L1 and L2 tone datasets. The current study explores three analyses designed to compare L1 and L2 tone: (1) using a single deviation score, (2) using deviation score calculations for specific regions of tone productions, and (3) applying a complexity-invariant distance measure to the two time series datasets. These three analyses were tested using datasets sampled from a previous study testing the effects of a visual feedback paradigm on the production of L2 Mandarin tone. Results suggest the first two analyses, although useful for providing an overall evaluation of how L2 speakers’ pretest versus posttest productions compare to L1 speakers, lose critical information about tone, namely pitch height, contour, and the timing of the production. The third analysis, applying the complexity-invariant distance measure to the datasets, can provide the pertinent information lost from the first two analyses in a more robust manner
Strawberry Production in an Elevated Bench Growing System inside a High Tunnel in Southern Indiana
Get PDFObjective of this study is to evaluate the performance of eight strawberry cultivars grown in an elevated bench system. Yield and quality parameters were measured. This report also includes a discussion on production challenges and economic considerations of this production system