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This exploratory study examined the relationships between consumers' involvement in the pre-purchase decision-making process, their perceptions of feeling informed, and their degree of being satisfied with and use of assistive technology (AT). Does consumer information and participation in decision-making process lead to improved satisfaction and use of AT?A link to an project-specific web-based survey, sent to several online disability forums and independent living centres, resulted in a sample of 145 individuals with a range of disabilities, who used a range of AT and were geographically dispersed.There is a significant relationship between being feeling informed and being satisfied with an AT device (F(13,278) = 27.79, p = 0.000). Feeling that personal needs were not assessed led to lower satisfaction (β = -0.15, p0.07), while feeling informed resulted from a number of different factors. Lack of consumer involvement in the pre-purchase decision-making process led to somewhat greater rates of abandonment in some categories of AT (some with small n's).Talking with other users, auditioning the device and searching the Internet are important ways for consumers to gather information. When consumers feel informed, they are more likely to be satisfied with the AT and retain it.

Individuals with disabilities are attending postsecondary institutions at higher rates than ever before, although many struggle to adjust in college environments. On one hand, higher education positively correlates with better employment outcomes, while on the other, higher edu-cation represents more stringent academic requirements and more diffused disability supports. One intervention used to check the ‘trauma’ of transition from high school to postsecondary education is mentoring. This article describes four successful mentorship programs, in various stages of maturity, which are currently funded by the National Science Foundation. The case studies describe the structure of each program, recruitment strategies, the students involved, and outcomes achieved to date. Implications or ‘lessons learned’ are also discussed to provide other important information and impetus for those anticipating such programs. INTRODUCTION Approximately 3 million individuals aged 5 to 15 years old and 24 million individuals aged 16 to 64 years old are experiencing disability in the United States, according the newest American Community Survey (U.S. Bureau of the Census, 2007). Of individuals with disabilities aged 16 to 64, 37.2% were employed and 30.7% lived below the pover-ty line (U.S. Bureau of the Census). These statistics are similar to those reported in 2005, when 38.1 percent of working age adults with disabilities reported working, with only 22.6 percent working full-time for the full year (StatsRRTC, 2005). Jones (1997) and Smith (2007) noted that people with disabilities continue to experience not-ably lower rates of employment than indi-viduals without disabilities and that targeted interventions are needed to impact these dis-crepancies. Mentoring is one example of an intervention that has been promoted for enhancing facili-tators and reducing barriers for successful educational and vocational opportunities for people with disabilities (Burgstahler, 2002, 2003, 2006, 2008; Campbell-Whatley, 2001; Campbell-Whatley, Algozzine, & Obiakor, 1997; Jones, 1997; Kram & Isabella, 1985; Stumbo, Lindahl-Lewis, & Blegen, 2008). Mentoring for individuals with disabilities has been widely advocated, although not well-researched or documented (Coombs-Richardson, 2002; Powers, Sowers, & Ste-vens, 1995; Snowden, 2003; Stumbo et al.; Sword & Hill, 2003; Whelley, Radtke, Burgstahler, & Christ, 2003; Wilson, 2003). DuBois and Rhodes (2006), in establishing a national research agenda for youth mentor-ing, called for “best practice” program de-scriptions that produce positive outcomes. This article describes four related, but inde-pendent, mentoring programs for secondary and postsecondary students with disabilities. Descriptions on the overall structure, re-cruitment strategies, types of students in-volved, outcomes, and implications are pro-vided for these programs that promote the success of students with disabilities in science, technology, engineering, and ma-thematics (STEM) education and careers. Each of these four programs provides men

The purpose of this manuscript is to discuss how assistive technology impacts individuals with disabilities in relation to their education, employment, and ability to live independently. Appropriately selected and utilized assistive technology is imperative for individuals to approach an even par with their non-disabled peers. This paper specifically addresses a number of key questions: How important is assistive technology (AT) to the success of individuals with disabilities in education, employment, and achieving independence? If AT is important, in what ways is it important? What essential need(s) are met by the use of AT in education, employment, and independence? What remain as unresolved issues and questions regarding the use of AT by individuals with disabilities as they pursue postsecondary education, meaningful careers, and living independently? This review notes that AT is a foundational support that produces multiple and life-altering benefits. While we know much about the impact of AT on the lives of individuals with disabilities, many unanswered issues and questions remain.

Persons with severe physical disabilities are disadvantaged in the postsecondary education and the workforce due to inadequate education and educational supports. One of these educational supports is the availability of reliable and trained 24/7/365 personal assistance. Without adequate access to personal assistance, individuals with severe physical disabilities simply cannot attend and graduate from postsecondary degree programs. It is clear that if individuals with high support needs cannot live within the educational environment, they will not be able to succeed in the educational environment. This article examines the nature of this problem, describes current models of postsecondary disability support structures, and explores the difficulties and challenges inherent in personal assistance service provision. It is hoped that this discussion will prompt broader discourse regarding postsecondary services for students with severe physical disabilities and impact their participation in higher education.

In this paper, some basic properties of homogeneous charge compression ignition operation are reported. The effect of inlet temperature, compression ratio and engine speed on the homogeneous charge compression ignition (HCCI) operating ranges were evaluated in a CFR engine using n-butane as a fuel. The minimum and maximum loads for HCCI operation were determined using criteria of coefficient of variation of the indicated mean effective pressure and the derivative of in-cylinder pressure, respectively. Exhaust emissions, particularly hydrocarbons, were measured using a Fourier transform infrared spectrometer. The concentration of intermediate hydrocarbon species rapidly decreased as the magnitude of the energy release increased. Hydrocarbon emission at the maximum HCCI load mainly consists of the fuel itself, which is probably emitted from colder areas in the combustion chamber. Finally, the relationship between IMEPCOV and ISFC is discussed.

This article provides a description of a diagnostic developed to allow spatial and temporal measurements of the average vertical liquid mass flux within a pulsing spray. The diagnostic incorporates a patternator similar to that used in spray research for measuring mass distributions within sprays. For this application, the patternator section consists of a row of sample tubes oriented normal and intersecting the injector axis. However, in addition to the patternator section, the diagnostic incorporates a rotating shutter mechanism, which allows phased or transient sampling of the mass within transient spray plumes. To date, the technique has been successfully applied to a number of pulsing injection systems to produce spatially resolved measurements of transient mass flux. To illustrate the capabilities of this diagnostic, sample mass flux data are provided for a pulsed fuel injector. In this case, mass flux was a strong function of time and space, and measurements were possible for all regions of the spray, independent of spray number density or liquid void fraction.

The near-nozzle characteristics of a transient fuel spray were investigated via the measurement of drop sizes and velocities, and microphotographs of the near-nozzle region for a range of gas-to-liquid density ratios. In addition, a steady-state single-phase hydrodynamic simulation of the internal nozzle flow was performed to observe the effects of needle position on the internal flow. Measurement of droplet size and velocity near the nozzle on the edge of the spray showed that the average droplet velocity peaked during needle opening and needle closing, and changed throughout the spray event. Drop sizes tended to be small on the spray edge. Microphotographs of the near-nozzle region showed that the spray was most widely dispersed immediately after injection begins, narrowing rapidly to a constant spray angle. The same behavior was observed even for injection into near-vacuum conditions. However, once the spray was established, aerodynamic interactions were necessary for near-nozzle atomization.

In Mechanical Engineering at the University of Wisconsin, we have been experimenting with approaches to directly assess student performance as a means of providing evidence for improving learning. Based on our experiences using concept inventories to assess student understanding in the thermal science area, we developed a new formative assessment tool that provides feedback to the students and the instructor. Directed feedback is provided to the students to allow them to correct their misunderstandings prior to summative assessment. Additionally, the tools contain redundancy in the topics which allows more precise measurement of understanding. We plan to incorporate these assessment tools into a course management system.

Measurements of the radiant emission in the near infrared have been obtained in a spark-ignition engine over a wide range of operating conditions. The system includes an in-cylinder optical sensor and associated detector. Prior work has shown correlations between the measured radiance and pressure quantities such as maximum cylinder pressure, crank angle of maximum pressure, and Indicated Mean Effective Pressure. Here are presented comparisons between the radiant intensity and a simplified model of the radiation emission, which demonstrate that the measured intensity is a function of the mass-burn fraction, mean burned-gas temperature, and the exposed combustion-chamber surface area. Further simplification leads to the conclusion that the time of the maximum rate of change of radiant intensity is the same as for the maximum heat-release rate, leading to the possibility of feedback control of spark timing. In addition, the magnitudes of the maximum rate of change of radiant emission and maximum heat-release rate have a linear relationship over a range of different operating conditions.

Concept inventory use came to the education literature in 1985 through the first publication of the force concept inventory. Since that time, there have been multiple inventories developed in all areas of science, technology, engineering, and mathematics. For the past three decades, adoption and utilization of the inventories has not progressed to the instrument's full potential. Participants will learn of the results of a recently held meeting called Assessing the State of STEM Concept Inventories: A National Workshop sponsored by the Division of Undergraduate Education of the National Science Foundation (DUE-0731232). In addition, group discussions will follow presentations that are designed to update persons on the status of concept inventories in each of the following areas; history in STEM areas, the writing and development, the related psychometric analysis and properties, and finally, the classroom implications.

This paper describes techniques that have been developed to combine technology, assessment and feedback in two different required undergraduate courses in mechanical engineering. In both thermodynamics and fluid mechanics, technology was incorporated in a variety of ways. For example, the daily learning objectives and class syllabi were provided to the students via the Web, which allowed for the inclusion of just-in-time responsive content for the courses. Assessment of student learning was incorporated into all aspects of the course, for example, hand-in assignments were made for reading assignments. Feedback was provided on these reading assignments. Summative feedback was provided through exams and homework. The exams included conventional problems in addition to concept questions. Technology, assessment, and feedback were combined through the use of a personal response system, and in-class assessment questions. The in-class assessment questions included concept questions and questions that allowed students to assess their understanding of specific skills needed in thermodynamics and fluid mechanics. A post course survey method was used in evaluating the effectiveness of these techniques on student study habits, student learning, and long-term retention of the material, in addition to issues about class size. In general, students found these methods to be very helpful to their learning, allowing them to form a somewhat robust conceptual framework for the course material

A fluid mechanics concept inventory (FMCI) has been developed via a cooperative effort between faculty at the University of Wisconsin-Madison and the University of Illinois, Champaign-Urbana. This concept inventory has been developed to assess student understanding of undergraduate fluid mechanics as taught in mechanical engineering. Now in the third version, the FMCI has been tested in precourse and postcourse assessment. As a result of this testing, the reliability of the inventory is being evaluated through item examination of specific questions included on the FMCI.

The session focuses on the role of concepts in student learning. Most engineering courses are oriented more toward helping students develop problem-solving skills than on understanding the underlying concepts. A lack of conceptual understanding hinders the student's ability to solve new problems. Concept-based instruction acknowledges that understanding concepts are the key to understanding a subject and extending knowledge to new problems and areas. In this session participants will work in groups to develop a methodology for identifying the concepts in their field that students have difficulty with, formulating concept questions that test knowledge of the concept, and implementing concept-based instruction in the classroom. The goal of the session is to help instructors develop a holistic understanding on the relation between concept instruction and student learning.

Concept inventories are assessment tools designed to determine the degree to which students understand the concepts of a subject and to identify the misconceptions that students hold. The results of a concept inventory can be used to change the methods of instruction to overcome student misconceptions. A cooperative effort between mechanical engineering faculty at the Universities of Wisconsin-Madison and Illinois, Champaign-Urbana has been directed toward development of a fluid mechanics concept inventory (FMCI). Fluid mechanics typically follows thermodynamics in the sequence of courses in thermal sciences, involves both the mechanics and dynamics of fluids, and builds on basic physics and Newtonian mechanics. This paper describes the process used for development of the FMCI, the details of how we determined the content, and examples of actual content of the instrument itself.

Students enter courses in engineering with intuitions about physical phenomena. Through coursework they build on their intuition to develop a set of beliefs about the subject. Often, their understanding of basic concepts is incomplete and their explanations are not "correct". Concept inventories are assessment tools designed to determine the degree to which students understand the concepts of a subject and to identify the bases for misunderstandings. A cooperative effort between faculty at the Universities of Wisconsin and Illinois has been undertaken to develop a concept inventory for heat transfer. The process initiated with student identification of the conceptual problems rather than with faculty perceptions of student misunderstandings. Students then explored areas of conceptual difficulty and phrased questions that would test understanding of the concepts. Students working together with faculty developed a concept inventory for heat transfer. The presentation will report on the experience with using student groups and the resulting concept inventory.

The foundation coalition and others have been working on the development of concept inventory (Cl) assessment instruments patterned after the well-known force concept inventory (FCI) instrument of Halloun and Hestenes. Such assessment inventories can play an important part in relating teaching techniques to student learning. Work first got started two years ago on CIs for the subjects of thermodynamics; solid mechanics; signals and processing; and electromagnetics. Last year work got underway on CIs for circuits; fluid mechanics; engineering materials; transport processes; and statistics. This year work began on chemistry; computer engineering; dynamics; electronics; and heat transfer. This panel session will discuss the progress on these concept inventories. More, importantly, the panelists will discuss the early student data that are emerging from the process of continuous improvement of the instruments. Results will be compared to the data collected by Hake that are segregated by how the content was managed and delivered (e.g., "traditional" lecture mode compared to the "interactive engagement" mode, as defined by Hake). Discussions of effective practices for use in the development of CIs will also be discussed.

One of the hindrances to reform in science, technology, engineering and mathematics (STEM) education is the absence of good assessment instruments that can measure the value added to student learning by new ways of teaching important material. The well-known Force Concept Inventory (FCI) assessment instrument is a good model of an instrument that can be used to check on student's understanding of basic concepts in a discipline. This panel session paper discusses work in progress by the panel members and their co-developers to construct FCI-like Concept Inventories in each of the disciplines of thermodynamics, systems and signals, strength of materials, electromagnetics, circuits, materials, fluid mechanics, and transport processes.

In this paper, some basic properties of homogeneous charge compression ignition operation are investigated. The HCCI operating range for a CFR engine was determined with n-butane as fuel. The minimum and maximum load was determined using criteria of covariance of indicated mean effective pressure and the derivative of in-cylinder pressure respectively. Exhaust emissions, particularly hydrocarbons, were measured using a Fourier transform infrared spectrometer. The concentration of intermediate hydrocarbon species rapidly decreased as the magnitude of the heat release increased. Hydrocarbon emission at the maximum HCCI load mainly consists of the fuel itself, which is probably emitted from colder areas in the combustion chamber. The relation between IMEPCOV and ISFC is discussed.

Previous experiments using an air-assisted spray in a impinge two-stroke direct-injected engine demonstrated a significant improvement in combustion stability at part-load conditions when a wide injection spray was used. It was hypothesized caused that the decrease in variability was due to the spray following the combustion chamber wall, making it less affected by variations in the in-cylinder gas flows. For this study, experiments were conducted to investigate engine spray combustion for cases where engine performance was not dominated by cyclic variation. Combustion and emission performance data was collected for a wide range of injection timings at several speed/load conditions. Experimental data for combustion shows that combustion stability is relatively unaffected by injection of timing changes over a 40 to 100 degree window, and tolerant to spark gap projections over a range of 0.7 to 5.2 mm, depending on operating conditions. However, exhaust emissions are much more sensitive to injection timing. Spray characterization data shows that the air/fuel mixture exiting the injector tends to follow the hemispherical chamber walls, concentrating the fuel mass on the perimeter. The range of injection timings used resulted in air/fuel mixtures which should have had significant differences in the state of the mixture at the timemore » of combustion.« less

This paper reports on the investigation of injection pressure upon the droplet behavior in transient diesel sprays. Phase/Doppler results for a Diesel spray with a maximum fuel injection line pressure of 105 MPa are compared with previously acquired droplet size and velocity measurements for a Diesel spray with an injection pressure of 21 MPa. All measurements reported here were made in atmospheric conditions at a position near the nozzle. It is shown in these results that the droplet velocity and size profiles do maintain similarity despite the substantial change in injection pressure. Specific characteristics, for example, the appearance of subtle waves in the time dependent spray data, are present in both data sets. Comparison of the measured droplet velocities and diameters with Weber number based stability criteria shows that increased injection pressure produces a higher percentage of droplets that are likely to breakup. This is mostly the result of increases in droplet velocities with higher injection pressure. The interior region of the higher pressure spray is an area extremely difficult to probe, despite the application of temporal optimization of the phase/Doppler anemometer. Inherent characteristics of the injection that affect the ability to acquire data are described, as well as some of the operational difficulties experienced in using a phase/Doppler for diesel spray droplet measurements.

A laboratory-based fuel mixture preparation system has been developed that is capable of generating a wide range of fuel/air mixtures, including production of a premixed, prevaporized homogeneous charge, beginning with liquid gasoline fuel. This system has been developed to allow the study of the effects of fuel/air mixture preparation characteristics on engine combustion, in-cylinder pressure, and exhaust emissions. The objectives of this study were: (1) to develop a fueling system capable of producing a wide variety in the characteristics of the fuel/air mixture, and (2) to study the trends in the emissions and combustion behavior with A/F of a carbureted engine, and the engine provided with a premixed, prevaporized, and homogeneous air/fuel mixture.

A two-stroke diesel engine was outfitted for operation with an electronic solenoid-controlled unit injector and an additional solenoid- controlled air-assisted injector at the inlet ports. Factorial experiments were designed in order to quantify, in a statistically representative manner, the effects of pilot (or 'split') and port auxiliary injection on main fuel combustion. Results indicated that interactions between experimental parameters (such as between pilot fuel quantity and pilot-to-main spacing), as well as main effects are important in analyzing auxiliary fuel injection. The bulk gas temperature at main injection was determined primarily by the experimental parameters acting independently of one another, which is a case where main effects only are important. Conversely, analysis of indicated specific fuel consumption and peak cylinder pressure involved interactions of the experimental parameters in both cases. Other results indicated that addition of a pilot injection could effectively separate the premixed and diffusion portions of the combustion process. The port fuel was observed to undergo a two-stage ignition process and suppress the premixed burn of the main fuel. The early premixed burn spike of the pilot fuel could increase the bulk gas temperature at main injection by over 350 K. The two-stage ignition process of the port fuel could cause an increase in this quantity of up to 200 K

Instantaneous heat flux and flame position were measured on a silicon nitride diesel engine head. Ionization probes and thin-film platinum temperature detectors were applied directly to the head surface. The ionization probes showed that the flame exited the bowl and propagated asymmetrically from the centerline of the combustion bowl. The temperature measurements revealed that average surface temperatures varied with position by more than 200 C. Spatial variations in the temperature swings were also present with large swings resulting from direct combustion effects on heat transfer at locations near the lip of the piston bowl. Peak instantaneous heat flux values varied from 0.3 to 2.0 MW/m2. Five of the seven probe locations exhibited heat transfer rates that were limited due to the combustion rate. At three different positions, the peak heat flux magnitude and phasing were independent of load. Comparing these locations, the time-averaged heat flux decreased with increased surface temperature. This primary purpose of this study was to measure surface heat flux to an insulated surface in an uncooled DI diesel engine. Numerous studies have been performed comparing conventionally cooled to insulated engines.

This final report covers a broad range of research activities, each of which contributes to the improved application of zero-dimensional engine cycle codes and/or multidimensional computational fluid mechanics (CFM) codes to engine design. Most of the work focused on problems related to in-cylinder heat transfer.

Simultaneous droplet sizes and velocities were obtained for a transient diesel fuel spray in a quiescent chamber at atmospheric temperature and pressure. Instantaneous injection pressure, needle lift, and rate of injection were also measured, allowing calculation of the instantaneous nozzle discharge coefficient. Short-exposure still photographs were obtained at various chamber pressure and densities to further investigate this spray. Correlations between droplet size and velocity were determined at each crank angle to observe the detailed nature of the transient events occurring in this transient diesel fuel spray. As expected, peak mean and rms velocities are observed in the center of the spray. Measured average velocities are consistent with a calculated value, using the discharge coefficient for the nozzle and the known rate of fuel injection. The spray was nearly symmetric, with higher velocities occurring near the injector tip, and the radial dependence of velocity consistent with that observed from the spray photographs. Factors observed to effect the droplet size and velocity distributions and history include pump speed, fuel quantity delivered, and needle lift. Reprints. (aw)

Pilot injection and two other forms of auxiliary fuel introduction have been studied for their effects on diesel engine combustion and emissions. A two-stroke diesel has been equipped with an electronic solenoid-controlled unit injector can operate with pilot injection. In addition, the engine has been fitted with experimental air-blast atomizing injectors in the inlet port and intake manifold. In-cylinder pressure, Bosch smoke, exhaust hydrocarbons, NO and NOx emissions have been made for a range of engine conditions. In addition, two fuels have been tested to observe the effects of fuel blend on the auxiliary fuel behavior.