3 resultados para Remedy

em Digital Commons - Michigan Tech


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During my Peace Corps service as a community health liaison in rural Uganda I noticed that many improved water wells in our area had been abandoned. The communities described the water in these wells as being reddish in color, having a foul taste and odor, discoloring clothes and food, and not able to produce lather for washing. Personal investigations and an initial literature search suggested that the primary contaminant was iron. The water in these wells had a low pH and a rusty metallic smell. The water produced early in the morning appeared very red but the water became more transparent as pumping continued. The iron components of many of these wells experienced accelerated corrosion resulting in frequent pump failure. This rapid corrosion coupled with the timing of the onset of iron contamination (months to years after these wells were completed) suggests that the most likely cause of the poor quality water was iron related bacteria and/or sulphate reducing bacteria. This report describes a remedy for iron contamination employed at 5 wells. The remedy involved disinfecting the wells with chlorine and replacing iron pump components with plastic and stainless steel. Iron concentrations in the wells were less than 1 mg/L when the wells were drilled but ranged from 2.5 to 40 mg/L prior to the remedy. After the remedy was applied, the total iron concentrations returned to levels below 1 mg/L. The presence of iron related bacteria was measured in all of these wells using Biological Activity Reaction Tests. Although IRB are still present in all the wells, the dissolved iron concentrations remain less than 1 mg/L. This remedy is practical for rural areas because the work can be performed with only hand tools and costs less than US $850. Because the source of iron contamination is removed in this approach, substantial follow-up maintenance is not necessary.

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In the autumn of 1913, a small, remote Michigan mining community attracted national attention as miners and management found themselves embroiled in a conflict that would prove no easy victory for either side. The strike came as a shock to management, who, with the help of a nearly perfected paternal system, had come to expect a generally docile and compliant workforce. But what was even more shocking was the involvement of the miners’ wives in the strike effort, and the lengths they went to in order to keep men from crossing the picket line. This paper focuses on that effort, arguing that the women of the Michigan copper country developed strike strategies that were derived from their domestic experience, and justified their involvement through maternal arguments. However, these public actions allowed the management to disregard the respect and courtesy generally given to the domestic sphere as police and private agents perpetrated a number of home invasions in an attempt to break the strike. The involvement of women in male dominated labor disputes (mining, steel productions) has been largely ignored in the literature due to their indirect connection to the company as wives and not workers. This paper seeks to remedy this gap, and gain a better understanding of that indirect relationship. Sources include newspaper articles, private correspondence, public investigation records, and oral histories, found largely in the Michigan Tech Archives and Copper Country Historical Collections, Michigan Technological University, Michigan.

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It is remarkable that there are no deployed military hybrid vehicles since battlefield fuel is approximately 100 times the cost of civilian fuel. In the commercial marketplace, where fuel prices are much lower, electric hybrid vehicles have become increasingly common due to their increased fuel efficiency and the associated operating cost benefit. An absence of military hybrid vehicles is not due to a lack of investment in research and development, but rather because applying hybrid vehicle architectures to a military application has unique challenges. These challenges include inconsistent duty cycles for propulsion requirements and the absence of methods to look at vehicle energy in a holistic sense. This dissertation provides a remedy to these challenges by presenting a method to quantify the benefits of a military hybrid vehicle by regarding that vehicle as a microgrid. This innovative concept allowed for the creation of an expandable multiple input numerical optimization method that was implemented for both real-time control and system design optimization. An example of each of these implementations was presented. Optimization in the loop using this new method was compared to a traditional closed loop control system and proved to be more fuel efficient. System design optimization using this method successfully illustrated battery size optimization by iterating through various electric duty cycles. By utilizing this new multiple input numerical optimization method, a holistic view of duty cycle synthesis, vehicle energy use, and vehicle design optimization can be achieved.