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An Analysis of Precision teachingPocock, Trudy Louise January 2006 (has links)
This research examined three components of precision teaching; charting, timed practices, and performance aims. In the first study beginner skaters performed two roller skating skills, forward crosses and back scissors, with the aim of increasing fluency in these skills using precision teaching methods. Skaters were told to perform the skills as fast as they could during 1-min practises, aiming at a set performance aim, or goal. After each timing skaters were told how many repetitions they had performed. One group charted back scissors only and the other forward crosses only. The skaters became faster in both skills and charting did not produce faster rates. The improvement seen may have been a direct result of the performance aims. Therefore the second study, using back crosses, compared a fixed, difficult performance aim (complete 50 per minute) for one group and an easier, flexible performance aim (beat your previous sessions' high score) for a second group. After each timing skaters were told how many back crosses they had performed. Performance rates increased similarly for both groups, thus the different performance aims did not have different effects, contrary to the goal-setting literature. A third study investigated this further. Skaters performed forward crosses and back scissors during a baseline condition, where there were no performance aims or feedback. Increases in performance rates for both skills occurred. In a second condition, a performance aim higher than their number of repetitions in the previous condition was set and feedback was given for one skill only. There was an immediate increase in rate of the targeted skill for 3 of the 4 skaters, suggesting that the goal, when given with feedback, influenced the rate at which the skaters performed the skill. In the fourth study, where the effect of feedback and practice was examined more closely, soccer players dribbled a ball in and out of cones. As expected those who took part in eight to ten sessions that were told to do their best (an easy goal) and not given feedback performed this skill faster than those who completed only two sessions with the same conditions. Unexpectedly, they also performed faster than those set a performance aim of beating their previous highest score (a hard goal) and who were given feedback. Methodological issues that may have been responsible for this latter result were addressed in the fifth study. Skaters completing 10 sessions of forward crosses, with feedback and with a performance aim of completing 60 repetitions in one minute (a hard goal), became faster than skaters completing 10 sessions without feedback who were told to do their best. Skaters told to do their best, who completed only three sessions without feedback, did not get faster. These results support those in the goal-setting literature that, hard goals with feedback have more effect than being told to do your best. Overall these studies show that short, timed practices and hard performance aims, or goals, may be effective components of precision teaching while visual feedback from charting may not. Further, precision teaching methods were effective when applied to sporting skills such as those used by roller skaters and soccer players for building fluency of basic skills.
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Salinity hazard mapping and risk assessment in the Bourke irrigation districtBuchannan, Sam, Faculty of Science, UNSW January 2008 (has links)
At no point in history have we demanded so much from our agricultural land whilst simultaneously leaving so little room for management error. Of the many possible environmental impacts from agriculture, soil and water salinisation has some of the most long-lived and deleterious effects. Despite its importance, however, land managers are often unable to make informed decisions of how to manage the risk of salinisation due to a lack of data. Furthermore, there remains no universally agreed method for salinity risk mapping. This thesis addresses these issues by investigating new methods for producing high-resolution predictions of soil salinity, soil physical properties and groundwater depth using a variety of traditional and emerging ancillary data sources. The results show that the methodologies produce accurate predictions yielding natural resource information at a scale and resolution not previously possible. Further to this, a new methodology using fuzzy logic is developed that exploits this information to produce high-resolution salinity risk maps designed to aid both agricultural and natural resource management decisions. The methodology developed represents a new and effective way of presenting salinity risk and has numerous advantages over conventional risk models. The incorporation of fuzzy logic provides a meaningful continuum of salinity risk and allows for the incorporation of uncertainty. The method also allows salinity risk to be calculated relative to any vegetation community and shows where the risk is coming from (root-zone or groundwater) allowing more appropriate management decisions to be made. The development of this methodology takes us a step closer to closing what some have called our greatest gap in agricultural knowledge. That is, our ability to manage the salinity risk at the subcatchment scale.
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Development of New Cooling Methods for GrindingNguyen, Thai January 2005 (has links)
Doctor of Philosophy / This research aimed to develop new cooling methods to replace, or at least minimise, the use of currently used grinding coolants which are known to be harmful to the environment. The methods used involved the application of a cold air and vegetable oil mist mixture (CAOM), and the use of liquid nitrogen as cooling media. Allied research focused on the development of a segmented grinding wheel equipped with a coolant chamber. The feasibility of a grinding system using CAOM was assessed on the surface grinding of plain carbon steel 1045. It was found that at low material removal rates, ground surfaces were obtained with a quality comparable to that from grinding with a conventional coolant in association with a reduction of grinding forces. There was no significant difference in the subsurface hardness of the components using CAOM, although the latter method showed a stronger dependence of surface residual stresses on the depth of cut due to the limit in cooling capacity of CAOM. The effects of using liquid nitrogen as a cooling medium on the microstructure of quenchable steel were explored. It was found that a martensite layer was induced on the ground surface. The microstructure featured a dispersion of very fine carbides within the martensite lattice, resulting in a remarkable increase in hardness and high compressive residual stresses within the layer. The topography of the ground surfaces indicated that the material was predominantly removed by brittle fracture. Furthermore surface oxidisation was suppressed. In the interest of coolant minimisation, a segmented wheel equipped with a pressurized coolant chamber was developed. A higher quality ground surface was obtained in conjunction with a coolant saving of up to 70%. In addition, the adhesion of ground chips on the wheel surface largely disappeared. Furthermore, surface tensile residual stresses caused by thermal deformation were minimised. The mechanism of coolant disintegration to form mists using this type of wheel system was studied. The Weber theory for Newtonian jet instability was applied to quantitatively determine the contribution of coolant flow rate to mist and ligament modes. A semi-analytical model was then developed to predict the mist flow rate by taking into account both grinding parameters and coolant properties. The model prediction was in agreement with experimental measurements. Based on the principles of fluid motion and the mechanisms of spin-off and splash, analytical models for both conventional and segmented wheels were established to provide a physical understanding of the mechanisms of coolant penetration into the grinding zone. Coolant minimisation was evident using the segmented wheel where the coolant pumping power into the grinding zone increased with wheel speed, but for the conventional wheel it decreased. A quantitative analysis was developed that accounted for the coolant properties and system design characteristics governing the penetration mechanism revealed by the theory established above. In conjunction with the mist formation analysis, the developed model offers a practical guideline for the optimal use of grinding coolants in achieving a balance between the demands of productivity and care for the environment.
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Extending the utility of machine based height sensors to spatially monitor cotton growthGeiger, David William 30 September 2004 (has links)
The recommended procedures for implementing COTMAN; a cotton management expert system; suggest frequent crop scouting at numerous locations for each field. Machine based height sensors coupled with the ability to spatially record height values make it possible to locate regions of a field that are height representative of the entire field. A machine based height measurement system called HMAP was used to assess plant height in various fields in the 2003 growing season while the same fields were monitored with COTMAN. The plant height data was used to determine an optimal COTMAN sampling scheme for each field consisting of significantly fewer sampling locations than recommended by COTMAN. It was possible to ascertain equivalent information from COTMAN using two sites selected from height data in place of six sites selected per COTMAN recommendations. The HMAP system was extended to monitor rate of growth in real time in addition to plant height by comparing historical plant height data recorded on previous field passes to current height values. The rate of growth capable HMAP system will make it possible to track cotton growth and development with an automated system.
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Mapping in-field cotton fiber quality and relating it to soil moistureGe, Yufeng 15 May 2009 (has links)
The overarching goal of this dissertation project was to address several fundamental aspects of applying site-specific crop management for fiber quality in cotton production. A two-year (2005 and 2006) field study was conducted at the IMPACT Center, a portion of the Texas A&M Research farm near College Station, Texas, to explore the spatial variability of cotton fiber quality and quantify its relationship with in-season soil moisture content. Cotton samples and in-situ soil moisture measurements were taken from the sampling locations in both irrigated and dry areas. It was found that generally low variability (CV < 10%) existed for all of the HVI (High Volume Instrument) fiber parameters under investigation. However, an appreciable level of spatial dependence among fiber parameters was discovered. Contour maps for individual fiber parameters in 2006 exhibited a similar spatial pattern to the soil electrical conductivity map. Significant correlations (highest r = 0.85) were found between most fiber parameters (except for micronaire) and in-season soil moisture in the irrigated areas in 2005 and in the dry area in 2006. In both situations, soil moisture late in the season showed higher correlation with fiber parameters than that in the early-season. While this relationship did not hold for micronaire, a non-linear relationship was apparent for micronaire in 2006. This can be attributed to the boll retention pattern of cotton plants at different soil moisture levels. In addition, a prototype wireless- and GPS-based system was fabricated and developed for automated module-level fiber quality mapping. The system is composed of several subsystems distributed among harvest vehicles, and the main components of the system include a GPS receiver, wireless transceivers, and microcontrollers. Software was developed in C language to achieve GPS signal receiving, wireless communication, and other auxiliary functions. The system was capable of delineating the geographic boundary of each harvested basket and tracking it from the harvester basket to the boll buggy and the module builder. When fiber quality data are available at gins or classing offices, they can be associated with those geographic boundaries to realize fiber quality mapping. Field tests indicated that the prototype system performed as designed. The resultant fiber quality maps can be used to readily differentiate some HVI fiber parameters (micronaire, color, and loan value) at the module level, indicating the competence of the system for fiber quality mapping and its potential for site-specific fiber quality management. Future improvements needed to make system suitable for a full-scale farming operation are suggested.
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Accuracy and precision of a technique to assess residual limb volume with a measuring-tapeJarl, Gustav January 2003 (has links)
Transtibial stump volume can change dramatically postoperatively and jeopardise prosthetic fitting. Differences between individuals make it hard to give general recommendations of when to fit with a definitive prosthesis. Measuring the stump volume on every patient could solve this, but most methods for volume assessments are too complicated for clinical use. The aim of this study was to evaluate accuracy and intra- and interrater precision of a method to estimate stump volume from circumferential measurements. The method approximates the stump as a number of cut cones and the tip as a sphere segment. Accuracy was evaluated theoretically on six scanned stump models in CAPOD software and manually on six stump models. Precision was evaluated by comparing measurements made by four CPOs on eight stumps. Measuring devices were a wooden rule and a metal circumference rule. The errors were estimated with intraclass correlation coefficient (ICC), where 0,85 was considered acceptable, and a clinical criterion that a volume error of ±5% was acceptable (5% corresponds to one stocking). The method was accurate on all models in theory but accurate on only four models in reality. The ICC was 0,95-1,00 for intrarater precision but only 0,76 for interrater precision. Intra- and interrater precision was unsatisfying when using clinical criteria. Variations between estimated tip heights and circumferences were causing the errors. The method needs to be developed and is not suitable for stumps with narrow ends. Using a longer rule (about 30 cm) with a set square end to assess tip heights is recommended to improve precision. Using a flexible measuring-tape (possible to disinfect) with a spring-loaded handle could improve precision of the circumferential measurements.
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An Instruction Scratchpad Memory Allocation for the Precision Timed ArchitecturePrakash, Aayush 11 December 2012 (has links)
This work presents a static instruction allocation scheme for the precision timed architecture’s (PRET) scratchpad memory. Since PRET provides timing instructions to control the temporal execution of programs, the objective of the allocation scheme is to ensure that the explicitly specified temporal requirements are met. Furthermore, this allocation incorporates instructions from multiple hardware threads of the PRET architecture. We formulate the allocation as an integer-linear programming problem, and we implement a tool that takes binaries, constructs a control-flow graph, performs the allocation, rewrites the binary with the new allocation, and generates an output binary for the PRET architecture. We carry out experiments on a modified version of the Malardalen benchmarks to illustrate that commonly known ACET and WCET based approaches cannot be directly applied to meet explicit timing requirements. We also show the advantage of performing the allocation across multiple threads. We present a real time benchmark controlling an Unmanned Air Vehicle as the case study.
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MAGNETIC RESONANCE IMAGING OF PROXIMAL FEMUR AND SURROUNDING MUSCLES: IN VIVO PRECISION2013 September 1900 (has links)
Background: Hip fractures are a major health problem in Canada, and two main contributors to hip fracture are weak bone strength and fall. Weak muscles also negatively affect bone strength and increase the likelihood of falling. Advanced imaging techniques, such as magnetic resonance imaging (MRI), offer in vivo measurement of bone strength and muscle area at the proximal femur. However, it is not known if MRI-based measurements of bone and muscle properties are repeatable (i.e. precise).
Methods: The femoral neck and shaft of 14 healthy participants were scanned three times, using a 1.5T MRI with repositioning between scans. Boundaries of the femoral neck, shaft and four muscle groups were delineated semi-automatically. Geometrical and strength properties of bone and area of muscle groups were determined based on segmented images. The short-term precision errors (root mean square coefficient of variation; CVrms%) between the repeated measures were calculated accordingly.
Results: MRI-based measures of bone geometry and strength and muscle area at the proximal femur demonstrated in vivo precision errors < 7.6%. The average CVrms% for bone measures and muscle area were less than 4% and 2.5% respectively. Higher CVrms% (e.g. average: 4.8%) was obtained for bone strength properties.
Conclusion: This is the first study to evaluate the in vivo performance of MRI on application to the proximal femur and surrounding muscles. Results demonstrate that MRI is a promising non-ionizing technique that offers precise measures of bone and muscle at the proximal femur.
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Precision Marketing Management : probe into way of existence of chinese small and medium-sized enterprises (SMEs) by analyzing parker hannifin (china)LIU, JUN January 2011 (has links)
Purpose/Research questions Aiming at the problem that the management efficiency of many Chinese small and medium-sized enterprises is generally low, the paper is to find the method in the aspect of marketing management to improve the management for the enterprise to meet challenges of globale market competition. According to the thoughts of Kotler(2006, p814), the future marketing shall be in a direction towards holistic marketing from marketing department . The paper discusses whether it is feasible for the Chinese small and medium-sized enterprises to use the precision marketing management method to optimize and integrate the resources and improve enterprises’ capacity. Research design/methodology/Approach The paper discusses the feasibility of the research subject through combination of theoretical research and case discussion. Analyze and discuss on experience of Parker Hannifin(China) to summarize ideas and implementation methods of precision marketing management to provide reference to the management of Chinese small and medium-sized enterprises. Findings Through the analysis and discussion on Parker Hannifin(China) and combination of marketing theory and value chains theory, I find that lean thinking may help the small and medium-sized enterprises inChinato utilize the limited resources in a reasonable way and improve enterprise capacity. Research limitations/implications Starting with marketing management, the paper discusses how to improve the efficiency of value delivery and thus win advantage through changing the extensive management method of enterprises. However, the small and medium-sized enterprises inChinastill have the problems such as brand resources and technological resources, etc., therefore, precision marketing can not generally improve the enterprises’ comprehensive competitive capability. Several competition methods, such as technique introduction, strategy alliance and so on are still needed to improve the enterprise’ comprehensive competitive capability, only in this way can the enterprises may win in the competition. Originality/value of the research Different from other papers, the paper, in the light of the characters of Chinese existing small and medium-sized enterprises, mainly discusses the application of precision marketing management of small and medium-sized enterprises adopting extensive management. Therefore, it has the particularity in marketing cultural environment, such as Chinese policy and customers' preference; its application shall be more specific, and has stronger pertinence.
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Design and Control of a Compact 6-Degree-of-Freedom Precision Positioner with Linux- Based Real-Time ControlYu, Ho 14 January 2010 (has links)
This dissertation presents the design, control, and implementation of a compact highprecision
multidimensional positioner. This precision-positioning system consists of a
novel concentrated-field magnet matrix and a triangular single-moving part that carries
three 3-phase permanent-magnet planar-levitation-motor armatures. Since only a single
levitated moving part, namely the platen, generates all required fine and coarse motions,
this positioning system is reliable and potentially cost-effective. The three planar
levitation motors based on the Lorentz-force law not only produce the vertical force to
levitate the triangular platen but also control the platen's position and orientation in the
horizontal plane. Three laser distance sensors are used to measure vertical, x-, and yrotation
motions. Three 2-axis Hall-effect sensors are used to determine lateral motions
and rotation motion about the z-axis by measuring the magnetic flux density generated by
the magnet matrix.
This positioning system has a total mass of 1.52 kg, which is the minimized mass to
produce better dynamic performance. In order to reduce the mass of the moving platen, it is made of Delrin with a mass density of 1.54 g/cm3 by Computer Numerical Controlled
(CNC) machining. The platen can be regarded a pure mass, and the spring and damping
effects are neglected except for the vertical dynamic. Single-input single-output (SISO)
digital lead-lag controllers and a multivariable Linear Quadratic Gaussian (LQG)
controller were designed and implemented. Real-time control was performed with the
Linux-Ubuntu operating system OS. Real Time Application Interface (RTAI) for Linux
works with Comedi and Comedi libraries and enables closed-loop real-time control.
One of the key advantages of this positioning stage with Hall-effect sensors is the
extended travel range and rotation angle in the horizontal mode. The maximum travel
ranges of 220 mm in x and 200 mm in y were achieved experimentally. Since the magnet
matrix generates periodical sinusoidal flux densities in the x-y plane, the travel range can
be extended by increasing the number of magnet pitches. The rotation angle of 12 degrees was
achieved in rotation around z. The angular velocities of 0.2094 rad/s and 4.74 rad/s were
produced by a 200-mm-diameter circular motion and a 30-mm-diameter spiral motion,
respectively. The maximum velocity of 16.25 mm/s was acquired from over one pitch
motion. The maximum velocity of 17.5 mm/s in a 8-mm scanning motion was achieved
with the acceleration of 72.4 m/s2. Step responses demonstrated a 10-um resolution and
6-um rms position noise in the translational mode. For the vertical mode, step responses
of 5 um in z, 0.001 degrees in roation around x, and 0.001 degrees in rotation around y were achieved.
This compact single-moving-part positioner has potential applications for precisionpositioning
systems in semiconductor- manufacturing.
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