Irvine, Joshua Lelemia
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ItemIntegrating an anaerobic Bio-nest and an aerobic EMMC process as pretreatment of dairy wastewater for reuse: a pilot plant study( 2009-04)A large dairy farm located on the island of Oahu, Hawaii was the site for an investigation for the potential integration of the existing facultative lagoon system with a cost effective pretreatment unit process. Based on the results from a laboratory study, a pilot plant was installed with two anaerobic bioreactors (10 m3 each) and one aerobic reactor (3.8 m3 ). Two layers of media ‘‘Bio-nest,’’ providing a void volume of 98%, were placed into each anaerobic bioreactor with 19% space-based on the bioreactor water volume. For better performance and reduction of shock-load, the equalization/settling tank was employed prior to the first anaerobic Bio-nest reactor. The intermediate holding tank settled effluent suspended solids from the Bio-nest reactor and adjusted the loading rate in order to improve the performance of the aerobic EMMC (entrapped mixed microbial cell) bioreactors. Based on the start-up operation of the Bio-nest system at an organic loading rate of about 1.5 g TCOD/l/day, the production rate of biogas from the first and second Bio-nest reactors was 0.64 and 0.15 l/l/day, respectively. This indicates that the anaerobic degradation of organics occurs mainly in the first Bio-nest reactor due to the low loading rate. The removal efficiency from the Bio-nest system shows TCOD removal of about 70%. The EMMC process provided fur- ther treatment to achieve a removal efficiency of TCOD at about 50% and a TN of about 35%. The cost for these pretreatments in order to be integrated with the existing lagoon system is US $1.1 per 1,000 gallons (3.8 m3) for dairy wastewater and $91 for each ton of TCOD removal. This integration system provides a sustainable improvement of environment and agricultural production.
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ItemEMMC technology for treatment/reuse of dilute dairy wastewater( 2009-04-13)A rural dairy farm located on the island of Oahu, Hawaii needed to upgrade current lagoon treatment system for further reuse as floor flushing and crop irrigation. This is a comprehensive bench scale and pilot plant study to evaluate the potential biological treatment and reuse systems. Systems evaluated include: (1) pre-existing lagoon system, (2) integrated anaerobic BIO-NEST/aerobic EMMC (entrapped mixed microbial cell) system, (3) aerobic EMMC reactor only system. Based upon a comprehensive economic evaluation and sensitivity analysis, the EMMC-only system achieved the best effluent quality for simultaneous removal of carbon and nitrogen. The pilot study of the EMMC-only reactor achieved an overall of 78% TCOD, 63% SCOD, 65% TN, and 96% soluble NH3-N removal efficiencies (HRT 12 h, continuous aeration). Implementing this system would cost about $0.25 a cow/ day to remove a ton of organic TCOD ($88.10/cow/year). The information presented provides a model for animal producers to consider in evaluating alternatives to upgrade existing waste management facilities.
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ItemNative Hawaiians in Engineering: A Path the Professoriate(American Society for Engineering Education, 2018-06)In this paper and presentation, a research team of engineers and educators from the University of Hawai‘i at Mānoa will present early findings from a three-phase, mixed-methods study where they sought to understand the gaps in progression of Native Hawaiian students to an academic career in engineering. The study is grounded in Tinto’s integration framework and Bean’s student attrition models, in which authors look at persistence in higher education. Tinto and Bean both suggested that students are more likely to persist in college if they are connected to both the academic as well as social life. Where both Tinto and Bean were primarily studying undergraduates, this study further explores the engineering graduate students' persistence, motivation, and the idea of connection to the Hawaiian culture. Furthermore, the study seeks to extends Bean’s work regarding higher education faculty where he suggested that intrinsic factors such as being true to self and valuing of students were essential characteristics for new faculty. One of the most underrepresented ethnic groups in engineering may be Native Hawaiians (NH). According to the 2011 US Census, the combined working population of NHs, Pacific Islanders, and ‘Other Race’ (grouped by U.S. Census due to small sample size) represents 4.6% of the total U.S. workforce but only 1.4% of science, technology, engineering, and mathematics (STEM) occupations. This makes NHs and Pacific Islanders the most underrepresented ethnic groups in the nation in STEM employment. Additionally, the U.S. Census national data indicates that only 700 single-race NHs or other Pacific Islanders received doctoral degree in science, engineering, and health fields in 2008. First, selected data are shared from a 43-item undergraduate survey administered to engineering students asking about background and preparation to pursue engineering as a major (N=168). Barriers, support systems, financial aid, and self-perception of success between NH students (n=17) and non-NH students (n=151) differences and similarities will be discussed. Second, major themes that emerged from structured interviews with 6 of 8 NH engineering graduate students are presented, including a sense of belonging to their chosen major, past performance in academics, and family support, important factors for degree completion in underrepresented groups such as Hawaiians, Filipinos, African-American and Blacks Hispanics, and women in science, technology, engineering, and mathematics (STEM) fields. Third, a short description of a six-workshop series called A‘o in Engineering and research and teaching opportunities designed to support interested senior and graduate engineering students (N=20) will follow. The authors end with a proposed education model to increase NH career interest in the engineering professoriate.
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ItemStuck on answering dynamics problems( 2015-08-28)Stuck on answering dynamics problems? This handout give a step-by-step method to approach and solve dynamics problems. Trust the process. This method will help one to think it through.
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ItemStudy Tips for Success in Engineering Mechanics( 2015-08-28)The purpose of this handout is to suggest good study habits and tips for success in engineering mechanics II, dynamics. Can be found in a blog post on my personal website: http://rainfarmer.weebly.com/wanderlust/study-tips-for-success-in-engineering-mechanics