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The design and development of a proto-type ceramic manual kick-wheel for the production of ceramic wares is the focus of this investigation. The problem of this study was how to improve on the manual kick-wheel usually characterized by wobbling as often prevalent among the locally produced ones. The general objective of this study was to develop a simple, easy to operate, maintain and above all cheaper to produce for cottage ceramic industries and for effective classroom teaching and learning where ceramics are being taught. To this effect, specific design standard, design considerations, design theories and calculations were generated and carried out. Initial design on paper was made as a working guide and was later developed using computer-Aided Design (CAD). The concern of the study was also to explore the possibility of using metal scraps from the junk yards for cost reduction and converting possible waste to wealth for the designing and fabricating a proto-type ceramic manual kick-wheel. For effective result achievement, material selections ranging from mild still, iron pipe, metal shaft, bearings, angle iron, cast aluminum disk, and so on were sourced for. Metal beneficiation was carried out for a rust free certification and spraying method was adopted using auto-car paint. The flywheel weight was a determinant factor for the high power rotation for effective clay centering and pulling resulting in less stress and convenience during operation. Raw materials such as Kaolin and Secondary Clays were also sourced for and beneficiated. Plywood was sourced for and used for the casting of moulds using Plaster of Paris (POP). The moulds were used for clay storage after its beneficiation and other treatments. From the result of the ceramic wares produced on the designed machine, it was established that the kick-wheel machine performed excellently well without wobbling, all the works thrown on the design machine were beautiful.

In the event of a failure of one of MAP's three reaction wheel assemblies (RWAs), it is not possible to achieve three-axis, full-state attitude control using the remaining two wheels. Hence, two of the attitude control algorithms implemented on the MAP spacecraft will no longer be usable in their current forms: Inertial Mode, used for slewing to and holding inertial attitudes, and Observing Mode, which implements the nominal dual-spin science mode. This paper describes the effort to create a complete strategy for using software algorithms to cope with a RWA failure. The discussion of the design process will be divided into three main subtopics: performing orbit maneuvers to reach and maintain an orbit about the second Earth-Sun libration point in the event of a RWA failure, completing the mission using a momentum-bias two-wheel science mode, and developing a new thruster-based mode for adjusting the inertially fixed momentum bias. In this summary, the philosophies used in designing these changes is shown; the full paper will supplement these with algorithm descriptions and testing results.

On-board the Mars Pathfinder spacecraft, launched in December of 1996, is a small roving vehicle named Sojourner. On Sojourner is an experiment to determine the abrasive characteristics of the Martian surface, called the Wheel Abrasion Experiment (WAE). The experiment works as follows: one of the wheels of the rover has a strip of black anodized aluminum bonded to the tread. The aluminum strip has thin coatings of aluminum, nickel and platinum deposited in patches. There are five (5) patches or samples of each metal, and the patches range in thickness from 200 A to 1000 A. The different metals were chosen for their differing hardness and their environmental stability. As the wheel is spun in the Martian soil, the thin patches of metal are abraded away, exposing the black anodization. The abrasion is monitored by measuring the amount of light reflected off of the samples. A photodetector was developed for this purpose, and that is the subject of this paper.

The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms. Sponsored and organized by the Mechanisms Education Association, responsibility for hosting the AMS is shared by the National Aeronautics and Space Administration and Lockheed Martin Space Systems Company (LMSSC). Now in its 43rd symposium, the AMS continues to be well attended, attracting participants from both the U.S. and abroad. The 43rd AMS was held in Santa Clara, California on May 4, 5 and 6, 2016. During these three days, 42 papers were presented. Topics included payload and positioning mechanisms, components such as hinges and motors, CubeSats, tribology, and mechanism testing. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components. The high quality of this symposium is a result of the work of many people, and their efforts are gratefully acknowledged. This extends to the voluntary members of the symposium organizing committee representing the eight NASA field centers, LMSSC, and the European Space Agency. Appreciation is also extended to the session chairs, the authors, and particularly the personnel at ARC responsible for the symposium arrangements and the publication of these proceedings. A sincere thank you also goes to the symposium executive committee who is responsible for the year-to-year management of the AMS, including paper processing and preparation of the program. The use of trade names of manufacturers in this publication does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the National Aeronautics and Space Administration.

The James Webb Space Telescope is an infrared-optimized space telescope scheduled for launch in 201 3. Its 6.5-m diameter primary mirror will collect light from some of the first galaxies formed after the big bang. The Near Infrared camera (NIRCam) will detect the first light from these galaxies, provide the necessary tools for studying the formation of stars, aid in discovering planets around other stars, and adjust the wave front error on the primary mirror (Fig. 1). The instrument and its complement of mechanisms and optics will operate at a cryogenic temperature of 35 K. This paper describes tests and test results of the NIRCam Filter Wheel assembly prototype.

A co-creation study, where intended beneficiaries and third sector representatives will contribute to the development of a novel healthy eating toolkit for adults experiencing food insecurity. This toolkit will be informed by stakeholder input, the Behaviour Change Wheel guide and previous research conducted by the PhD student.

The views of thirty corporate executives were examined and analyzed on the role and usefulness of various types of formal, informal, and continuing educational experiences as preparation for successful careers in business management. Personal interviews were conducted with each executive, with similarities of attitudes and recommendations statistically summarized in the data analysis. The lack of meaningful correlative indices among the variables which related educational background and experience to senior executive achievement lent support to the premise that there is not necessarily a predictable cause/effect relationship. As a group, the respondents favored an undergraduate liberal arts orientation for executive career preparation. Respondents from scientific or technically oriented companies tended to advise those interested in a specific technology to pursue that course, and then add a Master's degree in Business Administration, and broaden their education later. However, educational background was clearly not held to be an important factor in the evaluation of candidates for top management. What appeared to count most at that level was the person's over-all ability, work record, future promise, and the extent to which they are sensitive toward, and can work with and through other people. (TA)

This article is from BMC Research Notes , volume 6 . Abstract Background: Improving postgraduate medical training is one important step to attract more medical students into general practice. Keeping pace with international developments moving to competence-based curricula for general practice training, the aim of this project was to develop and implement such a curriculum in Germany. Methods: A five-step, peer-based method was used for the curriculum development process including panel testing and a “test version” of the curriculum for the pilot implementation phase. The CanMEDS framework served as a basis for a new German competence-based curriculum in general practice training. Four curricula from European countries and Canada were reviewed and, following required cultural adaptions, key strengths from these were integrated. For the CanMEDS “medical expertise” element of the curriculum, the WONCA ICPC-2 classification of patient’s “reason for encounters” was also integrated. Results: Altogether, 37 participants were involved in the development process representing 12 different federal states in Germany, and including an expert advisor from Denmark. An official “test version” of the curriculum consisting of three parts: medical expertise, additional competencies and medical procedures was established. A system of self-assessment for trainees was integrated into the curriculum using a traffic light scale. Since March 2012, the curriculum has been made freely available online as a “test version”. In 2014, an evaluation is planned using feedback from users of the test model as a further stage of the implementation process. Conclusions: The first German competence-based curriculum for general practice training has been developed using a pragmatic peer controlled approach and implementation is being trialed with a “test version” of the curriculum. This model project and its peer-based methodology may support competence-based curriculum development for other medical specialties both inside and outside Germany.

When the AiResearch Manufacturing Company of Arizona began to experience widespread premature failure of the two-piece turbine wheel in one of their radial inflow gas turbine engines, it was decided to develop a cast monoform (one piece) wheel of advanced aerodynamic shape to replace the two-piece assembly in existing ass well as future production units. This was accomplished using advanced casting techniques. This case study is part of the American Society for Engineering Education (ASEE) Engineering Case Library (ECL), which can be downloaded in full as a 300mb zip file . The Engineering Case Program originated at Stanford University in 1964 with the support of the National Science Foundation. It continues under the sponsorship of the ASEE.

The James Webb Space Telescope (JWST) will carry four scientific instruments, one of which is the Tunable Filter Imager (TFI), which is an instrument within the Fine Guidance Sensor. The Dual Wheel (DW) mechanism is being designed, built and tested by COM DEV Ltd. under contract from the Canadian Space Agency. The DW mechanism includes a pupil wheel (PW) holding seven coronagraphic masks and two calibration elements and a filter wheel (FW) holding nine blocking filters. The DW mechanism must operate at both room temperature and at 35K. Successful operation at 35K comprises positioning each optical element with the required repeatability, for several thousand occasions over the five year mission. The paper discusses the results of testing geared motors and bearings at the cryogenic temperature. In particular bearing retainer design and PGM-HT material, the effects of temperature gradients across bearings and the problems associated with cooling mechanisms down to cryogenic temperatures. The results of additional bearing tests are described that were employed to investigate an abnormally high initial torque experienced at cryogenic temperatures. The findings of these tests, was that the bearing retainer and the ball/race system could be adversely affected by the large temperature change from room temperature to cryogenic temperature and also the temperature gradient across the bearing. The DW mechanism is now performing successfully at both room temperature and at cryogenic temperature. The life testing of the mechanism is expected to be completed in the first quarter of 2010.

The James Webb Space Telescope is an infrared-optimized space telescope scheduled for launch in 201 3. Its 6.5-m diameter primary mirror will collect light from some of the first galaxies formed after the big bang. The Near Infrared camera (NIRCam) will detect the first light from these galaxies, provide the necessary tools for studying the formation of stars, aid in discovering planets around other stars, and adjust the wave front error on the primary mirror (Fig. 1). The instrument and its complement of mechanisms and optics will operate at a cryogenic temperature of 35 K. This paper describes tests and test results of the NIRCam Filter Wheel assembly prototype.

A pressure gauge which employs a relatively new pressure measuring concept and which can be permanently attached to an aircraft wheel was developed. The environmental and reliability testing demonstrated the ability of the system to withstand the extreme shock and accelerations associated with aircraft wheels without loss in accuracy. The development contract was also concerned with adapting the inflation measuring system to the standard KC-135 wheel. This required the design of a separable housing which replaced the valve stem of the tubeless tire and accommodated the pressure gauge. For future applications, it is suggested the gauge housing be made integral with the wheel rim casting rather than attached as a separate part.

A pressure gauge which employs a relatively new pressure measuring concept and which can be permanently attached to an aircraft wheel was developed. The environmental and reliability testing demonstrated the ability of the system to withstand the extreme shock and accelerations associated with aircraft wheels without loss in accuracy. The development contract was also concerned with adapting the inflation measuring system to the standard KC-135 wheel. This required the design of a separable housing which replaced the valve stem of the tubeless tire and accommodated the pressure gauge. For future applications, it is suggested the gauge housing be made integral with the wheel rim casting rather than attached as a separate part.

The Microwave Anisotropy Probe (MAP) is a follow-on mission to the Cosmic Background Explorer (COBE), and is currently collecting data from its orbit near the second Sun-Earth libration point. Due to limited mass, power, and financial resources, a traditional reliability concept including fully redundant components was not feasible for MAP. Instead, the MAP design employs selective hardware redundancy in tandem with contingency software modes and algorithms to improve the odds of mission success. One direction for such improvement has been the development of a two-wheel backup control strategy. This strategy would allow MAP to position itself for maneuvers and collect science data should one of its three reaction wheels fail. Along with operational considerations, the strategy includes three new control algorithms. These algorithms would use the remaining attitude control actuators-thrusters and two reaction wheels-in ways that achieve control goals while minimizing adverse impacts on the functionality of other subsystems and software.