2,500 research outputs found
Edifying the body while building the edifice
To help congregations more fully address the interface between confessional/theological self-understanding and building programs, a framework is developed that identifies three foci of concern. These call for and shape an \u27Architectural Brief/Educational Agenda\u27 for a congregation\u27s building program. A model/example of a Brief/Agenda within the Lutheran tradition is presented. The article concludes with a framework of activities to be incorporated into the educational dimension of any church building project
Manual control models of industrial management
The industrial engineer is often required to design and implement control systems and organization for manufacturing and service facilities, to optimize quality, delivery, and yield, and minimize cost. Despite progress in computer science most such systems still employ human operators and managers as real-time control elements. Manual control theory should therefore be applicable to at least some aspects of industrial system design and operations. Formulation of adequate model structures is an essential prerequisite to progress in this area; since real-world production systems invariably include multilevel and multiloop control, and are implemented by timeshared human effort. A modular structure incorporating certain new types of functional element, has been developed. This forms the basis for analysis of an industrial process operation. In this case it appears that managerial controllers operate in a discrete predictive mode based on fast time modelling, with sampling interval related to plant dynamics. Successive aggregation causes reduced response bandwidth and hence increased sampling interval as a function of level
Experimental studies on the aerodynamic performance and dynamic response of flow direction sensing vanes
Systematic investigations were performed on a variety of aerodynamic surfaces to obtain their potential for possible application to wind vanes. Among the surfaces tested were: (1) single vanes consisting of flat plates of various planforms having aspect ratios between 0.5 and 5; (2) bi-vanes with aspect ratio 2.5; (3) various cone and box vanes; and (4) various cruciform configurations. The models were subjected to windtunnel tests. In addition to lift and drag force measurements, damping and frequency test were performed under a variety of flow conditions
Replacing farm machinery
In talking of machinery replacement it seems implied that the replacement items of plant are bigger and therefore better than their predecessers. It is also implied that plant replacement is becoming more costly.
Before any decision to replace machinery, the reason for replacement should be carefully considered.
There may be alternatives to the bigger and better solution
Estimation of automobile-driver describing function from highway tests using the double steering wheel
The automobile-driver describing function for lateral position control was estimated for three subjects from frequency response analysis of straight road test results. The measurement procedure employed an instrumented full size sedan with known steering response characteristics, and equipped with a lateral lane position measuring device based on video detection of white stripe lane markings. Forcing functions were inserted through a servo driven double steering wheel coupling the driver to the steering system proper. Random appearing, Gaussian, and transient time functions were used. The quasi-linear models fitted to the random appearing input frequency response characterized the driver as compensating for lateral position error in a proportional, derivative, and integral manner. Similar parameters were fitted to the Gabor transformed frequency response of the driver to transient functions. A fourth term corresponding to response to lateral acceleration was determined by matching the time response histories of the model to the experimental results. The time histories show evidence of pulse-like nonlinear behavior during extended response to step transients which appear as high frequency remnant power
Hygrothermal damage mechanisms in graphite-epoxy composites
T300/5209 and T300/5208 graphite epoxy laminates were studied experimentally and analytically in order to: (1) determine the coupling between applied stress, internal residual stress, and moisture sorption kinetics; (2) examine the microscopic damage mechanisms due to hygrothermal cycling; (3) evaluate the effect of absorbed moisture and hygrothermal cycling on inplane shear response; (4) determine the permanent loss of interfacial bond strength after moisture absorption and drying; and (5) evaluate the three dimensional stress state in laminates under a combination of hygroscopic, thermal, and mechanical loads. Specimens were conditioned to equilibrium moisture content under steady exposure to 55% or 95% RH at 70 C or 93 C. Some specimens were tested subsequent to moisture conditioning and 100 cycles between -54 C and either 70 C or 93 C
Effects of manual and mechanical Ammophila arenaria removal techniques on coastal dune plant communities and dune morphology
The removal of invasive species as part of the restoration process can allow natives organisms to rebound. An ecosystem that incurs damages from invasive species is coastal sand dunes, which are dynamic systems. Some coastal sand dunes on the west coast of the United States have been invaded by Ammophila arenaria. The invasive grass, A. arenaria, is thought to alter and stabilize foredune morphology and reduce populations of native species. The objectives of my research are to examine the effects that manual and mechanical A. arenaria removal techniques have on coastal sand dune morphology and vegetative cover over time. The California State Parks Redwood District manages three coastal sand dune ecosystems where A. arenaria removal efforts have been conducted: Little River State Beach, Gold Bluffs Beach in Prairie Creek Redwoods State Park, and Tolowa Dunes State Park. I surveyed the vegetative cover at each of the three locations in each treatment method, manual and mechanical, and in untreated control plots during the summer and early fall of 2017. In order to measure dune morphology at restored and unrestored sites, I used an Unmanned Aerial Vehicle (UAV) that was flown over the mechanical removal and control areas. I then created a Digital Elevation Model (DEM) from photos taken during the UAV flights using Structure from Motion software. Overall, both mechanical and manual treatments lowered A. arenaria cover. Mechanical removal lowered the foredune elevation compared to control areas and changed the dune morphology in treatment areas into hummocks at Little River. Although mechanical removal was effective at lowering A. arenaria cover, it also lowered native plant diversity compared to manual removal, but was higher than control diversity. With endemic species of concern on coastal sand dunes, manual removal of A. arenaria will afford greater native plant diversity and cover compared to mechanical removal
Automation Laboratory Development With Design Implementation Scheme and Simulation Software
This paper describes the development of the Automation Control Lab in the Mechanical Engineering Technology Program of the Engineering Technology Department at Old Dominion University. The reorganization goal of the development is to help students design, test, and implement their automation designs effectively. Three processes are adopted to achieve this goal: (1) floor-plan design and inventory control of the components, (2) using Automation Studio to dynamically check each design, and (3) using industrial Programmable Logic Controllers (PLC) controllers to download PLC programs
Using Spreadsheet Programs in Teaching Machine Design
This paper presents an approach on using spreadsheets to teach machine design. It also lists detailed procedures on how to implement the teaching scheme. Results show that spreadsheet programs can help students organize their design procedures. By using the characteristics of spreadsheet programs, students do not have to repeat the same calculation and can get the alternate solution of a design almost instantly when given different values on the inputs. When compared to the method taught by using calculators, students can significantly improve their performance on homework problems and tests. From teaching evaluations, their interest in taking such a course increases. In addition, instructors can give more problems to students during tests and therefore can evaluate the students\u27 performance more objectively
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