2 resultados para Application specific instruction-set processor

em DRUM (Digital Repository at the University of Maryland)


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The last two decades have seen many exciting examples of tiny robots from a few cm3 to less than one cm3. Although individually limited, a large group of these robots has the potential to work cooperatively and accomplish complex tasks. Two examples from nature that exhibit this type of cooperation are ant and bee colonies. They have the potential to assist in applications like search and rescue, military scouting, infrastructure and equipment monitoring, nano-manufacture, and possibly medicine. Most of these applications require the high level of autonomy that has been demonstrated by large robotic platforms, such as the iRobot and Honda ASIMO. However, when robot size shrinks down, current approaches to achieve the necessary functions are no longer valid. This work focused on challenges associated with the electronics and fabrication. We addressed three major technical hurdles inherent to current approaches: 1) difficulty of compact integration; 2) need for real-time and power-efficient computations; 3) unavailability of commercial tiny actuators and motion mechanisms. The aim of this work was to provide enabling hardware technologies to achieve autonomy in tiny robots. We proposed a decentralized application-specific integrated circuit (ASIC) where each component is responsible for its own operation and autonomy to the greatest extent possible. The ASIC consists of electronics modules for the fundamental functions required to fulfill the desired autonomy: actuation, control, power supply, and sensing. The actuators and mechanisms could potentially be post-fabricated on the ASIC directly. This design makes for a modular architecture. The following components were shown to work in physical implementations or simulations: 1) a tunable motion controller for ultralow frequency actuation; 2) a nonvolatile memory and programming circuit to achieve automatic and one-time programming; 3) a high-voltage circuit with the highest reported breakdown voltage in standard 0.5 μm CMOS; 4) thermal actuators fabricated using CMOS compatible process; 5) a low-power mixed-signal computational architecture for robotic dynamics simulator; 6) a frequency-boost technique to achieve low jitter in ring oscillators. These contributions will be generally enabling for other systems with strict size and power constraints such as wireless sensor nodes.

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This study examines the organizational structures and decision-making processes used by school districts to recruit and hire school librarians. For students to acquire the information and technology literacy education they need, school libraries must be staffed with qualified individuals who can fulfill the librarian’s role as leader, teacher, instructional partner, information specialist, and program administrator. Principals are typically given decision rights for hiring staff, including school librarians. Research shows that principals have limited knowledge of the skills and abilities of the school librarian or the specific needs and functions of the library program. Research also indicates that those with specific knowledge of school library programs, namely school district library supervisors, are only consulted on recruiting and hiring about half the time. School districts entrust library supervisors with responsibilities such as professional development of school librarians only after they are hired. This study uses a theoretical lens from research on IT governance, which focuses on the use of knowledge-fit in applying decision rights in an organization. This framework is appropriate because of its incorporation of a specialist with a specific knowledge set in determining the placement of input and decision rights in the decision-making processes. The method used in this research was a multiple-case study design using five school districts as cases, varying by the involvement of the supervisors and other individuals in the hiring process. The data collected from each school district were interviews about the district’s recruiting and hiring practices with principals, an individual in HR, library supervisors, and recently hired school librarians. Data analysis was conducted through iterative coding from themes in the research questions, with continuous adjustments as new themes developed. Results from the study indicate that governance framework is applicable to evaluating the decision-making processes used in recruiting and hiring school librarians. However, a district’s use of governance did not consistently use knowledge-fit in the determination of input and decision rights. In the hiring process, governance was more likely to be based on placing decision rights at a certain level of the district hierarchy rather than the location of specific knowledge, most often resulting in site-based governance for decision rights at the school-building level. The governance of the recruiting process was most affected by the shortage or surplus of candidates available to the district to fill positions. Districts struggling with a shortage of candidates typically placed governance for the decision-making process on recruiting at the district level, giving the library supervisor more opportunity for input and collaboration with human resources. In districts that use site-based governance and that place all input and decision rights at the building level, some principals use their autonomy to eliminate the school library position in the allotment phase or hire librarians that, while certified through testing, do not have the same level of expertise as those who achieve certification through LIS programs. The principals in districts who use site-based governance for decision rights but call on the library supervisor for advisement stated how valuable they found the supervisor’s expertise in evaluating candidates for hire. In no district was a principal or school required to involve the library supervisor in the hiring of school librarians. With a better understanding of the tasks involved, the effect of district governance on decision-making, and the use of knowledge to assign input and decision rights, it is possible to look at how all of these factors affect the outcome in the quality of the hire. A next step is to look at the hiring process that school librarians went through and connect those with the measurable outcomes of hiring: school librarian success, retention, and attrition; the quality of school library program services, outreach, and involvement in a school; and the perceptions of the success of the school librarian and the library program as seen from students, teachers, administrators, parents, and other community stakeholders.