Spatial Centering of a Quadcopter in an Underground Coal Mine

The recent proliferation of smaller and more affordable sensing and computing has contributed to an increased availability of unmanned aerial vehicles, UAV\u27s. Specifically, quadrotor platforms have become popular due to their low cost, versatility, and relative ease of operation. There are a variety of applications for this type of aerial vehicle, ranging from hobbyist photography to search and rescue operations. This thesis documents the feasibility of using a quadrotor UAV within the confined space of an underground coal mine during an emergency. Additionally, this paper notes in the Appendix an experiment to remotely operate a quadcopter that is located underground. This work specifies the equipment used to operate down an eight inch borehole in terms of radios, fiber optic cables, and video hardware. The operator and quadcopter were located 50 feet apart in the experiment.;One of the most significant challenges of operating a quadcopter in an underground coal mine is collision avoidance. The automation of basic spatial centering in the underground coal mine would lessen the burden on the operator and help prevent collisions. Many spatially aware quadcopter systems already exist, but widely rely on GPS signals as a way to determine position. GPS signals are very weak radio signals that cannot penetrate into the earth. The below-ground nature of an underground coal mine precludes the use of GPS for positioning the craft. Due to this limitation, it became necessary to explore unique sensing solutions that would allow for the spatial centering of the quadcopter while operating in an underground environment.;The ability for the craft to maintain a distance from its surroundings through the use of a light-based sensor was analyzed. Sensors were placed on the bottom and side of the quadcopter, and the performance of the control system was observed. Altitude was maintained with a steady state error of 4%, and the response to a step change in ground height resulted in a 10% lower overshoot than simulation. Simultaneously, distance was maintained from the side with a steady state error of 7.8%. The work presented in this document serves as validation for the basic spatial awareness and crash avoidance capability of a quadcopter operating without GPS in an underground coal mine while controlled remotely down an eight inch borehole

Bacterial utilization and sequence determination of peptides

Preliminary experiments were performed to investigate the possibility of combining chemical blocking with microbiological assays in a method for determining terminal amino acids in peptides;A subtractive chromatographic procedure for determination of terminal amino acid residues in peptides is presented. Results are given for a total of nine dipeptides and one tripeptide. By employing selective cleavage of the treated tripeptide with dioxane-HCl the sequence of residues could be determined;The benzoyl derivatives of nine amino acids essential for L. arabinosus, of twelve amino acids essential for L. brevis , and one of ten amino acids essential for Strep. faecalis were tested for utilization by these micro-organisms. It was found that, under the conditions of the experiment, L. arabinosus could utilise only benzoyl-DL-leucine with efficiency, whereas activity so slight as to be questionable was noted for dibenzyol-L-leucine with efficiency, whereas activity so slight as to be questionable was noted for dibenzoyl-L-cystine. Only benzoyl-DL-methionine was available for Strep. faecalis. L. brevis used hippuric acid efficiently, while results for dibenzoyl-L-cystine were equivocal for this organism also. It should be noted, however, that only one strain of each species of bacteria was used, and the results obtained may apply only to these strains;Twelve benzoylated dipeptides and one benzoylated tripeptide containing leucine, phenylalanine, and valine residues were tested for availability to L. arabinosus. Only two, hippuryl-DL-leucine and benzoyl-DL-alanyl-DL-leucine were utilized, the microorganism seeming to show a requirement for leucine at the carboxyl end of the compound used. One other such compound, however benzoyl-DL-leucyl-DL-leucine A, gave little or no growth response;Three peptides were essayed for availability to L. arabinosus. One of these, DL-valyl-DL-leucine, was found to support growth in a leucine-free medium but not free medium. A possible explanation is presented

Developing dairy heifers

"March, 1962.

Letter from E. C. Itschner to Senator Langer Regarding Erosion Downstream of the Garrison Dam, May 2, 1955

This letter, dated May 2, 1955, from Brigadier General E. C. Itschner, Assistant Chief of Engineers for Civil Works, United States (US) Army Corps of Engineers to US Senator William Langer, refers to Langer\u27s letter of March 25 and its enclosed letter from a group of farmers concerned about the loss of farmland to erosion due to factors related to the construction of the Garrison Dam. Itschner writes that the lands in question have been inspected by representatives of the US Army Corps of Engineers, and gives some background on the nature of the lands in question and the rates of erosion prior to the construction of the Garrison Dam. Included with this letter is a map of the area in question with markings indicating erosion during prior periods. Itschner explains that, while the reduced peak flows and more stable flows resulting from the near-term operation of the dam may serve to reduce downstream erosion, there are other effects from the reservoir that may tend in the opposite direction, so that it is impossible to say whether the dam will ultimately increase or decrease downstream erosion. In any event, Itschner claims, there is no basis at present to conclude that the operation of Garrison Dam is accelerating downstream erosion rates. He states furthermore that the Corps of Engineers has no authority at present whereby they could expend federal funds for construction of the suggested remedial work, a reference to a suggestion by the downstream farmers that the riverbanks in question be protected by extensive rip rapping. See also: Letter from Nate Olds et al. to Senator Langer Regarding Erosion Along Missouri River Downstream of Garrison Dam, February 1, 1955 Letter from Senator Langer to Samuel D. Sturgis, Jr. Regarding Erosion Downstream of Garrison Dam, March 25, 1955 Letter From Louis L. De Noya to Senator Langer Regarding Erosion Downstream of the Garrison Dam, March 30, 1955https://commons.und.edu/langer-papers/2035/thumbnail.jp

Supper and picnic lunches

At head of title: "University of Missouri, College of Agriculture, Agricultural Extension Service. Published and Distributed in Furtherance of Acts of May 8 and June 30, 1914, Providing for cooperative Extension Work in Agriculture and Home Economics. J. W. Burch, Assistant Director in Charge of the Extension Service.""Prepared by E. T. Itschner, State Club Agent, in Collaboration with T. A. Ewing, Extension Animal Husbandman."Running header: Missouri Agricultural Extension Service.Title from cover.Revised

Raising dairy calves to breeding age

Reprint 3/67/3M.Title from caption

Calf feeding and management cow and calf management

"January, 1938, Reprinted, March 1940.""Prepared by T. A. Ewing, Extension Animal Husbandman, in collaboration with E. T. Itschner, State Club Agent."Appended to end, "Record blank for members in 4-H livestock clubs.

Music appreciation for 4-H clubs : a 4-H club activity

University of Missouri, College of Agriculture and the United States Department of Agriculture cooperating."April, 1941."Title from cover

Entwicklung von Modellen zur speichergestützten Versorgung mit regenerativen Energien in Inselnetzen

1. In dieser Arbeit wird eine Methode zur Auslegung von regenerativ betriebenen Versorgungssystemen als Inselnetz unter Verwendung von Energiespeichern vorgestellt. Basis für die Auslegung sind statistische Modelle der Leistungsprofile von Verbrauchern und Erzeugern sowie Modelle von Netz, Speichern und weiteren Komponenten, beispielsweise Dieselgeneratoren. Die am Versorgungssystem beteiligten Komponenten sind dabei modular und skalierbar gehalten, wirtschaftliche Parameter sind mittels Kostenmodellen hinterlegt. Die Auslegung der Versorgungssysteme wird mithilfe einer Optimierungssoftware umgesetzt, die die Gesamtkosten des Versorgungssystems minimiert. 2. Die Validierung der mit den statistischen Modellen erzeugten Leistungsprofile wurde anhand von Messungen aus zwei realen Versorgungsgebieten vorgenommen. Die Abweichungen der synthetischen Leistungsprofile zu den Messungen fielen dabei gering aus. Die mit der Optimierungssoftware gefundene Auslegung der Systemkomponenten wurde mittels eines dafür geschriebenen Scripts überprüft. Dabei konnten für die untersuchten Systeme eine ausreichend große Dimensionierung der Systemkomponenten festgestellt werden. Der Vergleich der angenommenen Systemkosten vor der Optimierung mit den Kosten der optimierten Systeme zeigt, dass regenerativ betriebene Inselsysteme mit Speichern mit den getroffenen wirtschaftlich sind