The nation of Antigua and Barbuda has experienced major degradation of its coral reef ecosystems over the past 40+ years. The primary drivers of this degradation are multiple and are highly linked to anthropogenic influences, including over-exploitation and poor management of marine resources. The effectiveness of management actions in marine protected areas (MPAs) has often been hampered by a lack of data to inform management recommendations. This was emphasized by The Nature Conservancy’s (TNC) Coral Reef Report Card which highlighted not only the lack of data collection in Antigua and Barbuda and other Caribbean nations, but also illustrated how spatially dispersed available datasets are. The government of Antigua and Barbuda recognized the need for a marine data collection program to better inform the designation and management of MPAs as a tool to improve the health of the marine ecosystems. The Atlantic Gulf Rapid Reef Assessment (AGRRA) protocol has been identified as a means to address planning and management for marine areas. Three AGRRA surveys have been conducted in the years following the TNC 2016 report, in previously established managed areas: North East Marine Management Area (NEMMA) in 2017 and Nelson Dockyard National Park (NDNP) in 2019 as well as areas outlined for future management (Redonda in 2018). Our surveys were conducted to provide updated datasets to inform management for the aforementioned areas. While the results of these surveys mirror the underlying poor coral reef-health conditions, which have been shown to exist within the Caribbean region, they also highlight intra-site variation that exists within each survey location. This knowledge can be crucial in guiding management decisions in these marine areas, through zoning and other management prescriptions. Additionally, the marine surveys conducted around Redonda established useful marine baselines to aid in monitoring the island’s recovery following removal of terrestrial invasive species. This article provides an overview of data collected using the AGRRA methodology in marine zones across Antigua and Barbuda which have current or future management prescriptions and provides recommendations to demonstrate the data’s future utilization for marine conservation and management.
This study experimentally measured the efficiency of new generation bicycle hub gears. Since efficiency of bicycle drivetrains can be very close to 100% and vary by small amounts between gears bias errors and measurement accuracy must be identified and controlled. For this study an ergometer frame was altered to support research test equipment. A 1 HP motor and gearbox were used to drive the crankshaft. The hubs were attached directly to the steel flywheel using shortened bicycle spokes, eliminating extra chains or drive components. This setup minimizes measurement uncertainty in the drivetrain. Force-transducers were used to measure the motor and flywheel torque, and two magnetic reed switches were used to measure the speed of the motor and flywheel. Efficiency for each individual gear in each hub was calculated for 14 different power speed combinations. The efficiency of each gear was plotted against flywheel Torque, and an exponential model was fit to the data. This model accounts for known variations in efficiency with power and speed, and provides insight into the torque-speed-efficiency relationship. Four internally-geared hubs were measured and compared with a single speed direct drive train and a belt drive. The internal planetary gear hubs measured were the Shimano Alfine 11, Rohloff 500/14 Speedhub, SRAM Dual-Drive, and the Sturmey Archer X-RK8(W). In addition a single-speed direct chain drive, a single-speed belt drive, and a 7-speed derailleur system were measured. The efficiency of the Shimano Alfine ranged from 90.4% to 96.6%. The efficiency of the Rohloff speed hub ranged from 95.8% to 99.5%. The efficiency of the Sturmey Archer hub ranged from 84.6% to 99.8%. The efficiency of the single speed chain drive was found to be 99.71% and the belt drive 98.0%. The efficiency of the 7-speed derailleur ranged from 97.7% to 99.4%. These values found for efficiency are comparable to other studies.
Grove City College participate in the college-wide business plan competition as one of their Capstone Design requirements. Capstone students work on teams focused on product development -including conception, design, market surveys, manufacturing, and production planning. Interdisciplinary teams include about six engineering students and one or two business students. They work together on the project during both the fall and spring semesters. A formal business plan is developed and submitted to the Annual Business Plan Competition near the middle of the spring semester. The plan is presented to judges from businesses near the end of the semester. Entrepreneurial topics are taught in required coursework, including the fall and spring semester Capstone Design courses and Engineering Economy. Topics specific to writing a business plan are included in the latter course. Many students also take a one-credit course on writing business plans which is offered by the Business Department. Results of the competition indicate the success of the program. In 2004, mechanical engineering teams placed second and third in the competition, although they comprise less than 5% of the student body.Intr oduction: Grove City College's Engineering Entrepreneurship Program is integrally tied with the senior Capstone Design Programs (in the Mechanical and Electrical Engineering departments) and the college-wide Annual Business Plan Competition (sponsored by the Business department.) Figure 1 illustrates the relationship between the three programs. Entrepreneurial topics, including cost estimation and financial performance prediction, were included in the senior design program for many years. The advent of the Business Plan Competition in 2003 provided a new opportunity for engineering students. A cooperative effort between the engineering departments and the Business department led to the creation of the Engineering Entrepreneurship Program. Business students and engineering students work together on cross functional teams to design a product, investigate market opportunities, plan for production, predict financial performance, and write a comprehensive business plan for the competition. Guidance and instruction for the business plan are taught in Engineering Economy (a required senior-level course) and the Business Planning course offered by the business department.
This study experimentally investigated pedal cycle frame loads and verified analytical load cases applied to vehicle design. The experimental results were compared with a Finite Element Analysis (FEA) model. The weight of the rider on the seat, road induced loads and vibrations, and the force the rider exerts on the pedals affect the stress state of the frame. Strain gauges were applied to two different frame models. Four different locations were tested on a monotube long-wheel base (LWB) recumbent frame and six locations on a standard upright Schwinn. The stress state was calculated from the raw strain data. Depending on the gauge being used, the results either indicated the von Mises stress or simply the axial stress. The different loading conditions tested were as follows: static, steady pedaling on smooth, mid-grade, and rough pavement, and hard acceleration on level ground and uphill. The static and hard acceleration cases were directly compared to the FEA model. The experimental results were comparable to the FEA analysis. The complexity of the load case, coupled with unknown actual loads, explains the larger differences between FEA and experimental results. Based on experimental results, the FEA model was refined, improving the agreement between model and experiment. The stress states of a bicycle frame were successfully found experimentally, being confirmed by multiple runs under each loading condition. Based on the agreement between the two methods, the use of FEA load cases to predict stresses in pedal cycle frames was verified.
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