1,326 research outputs found
A Design Environment for Product Knowledge Management and Data Exchange
This paper reports on a distributed design environment under development for product knowledge management and information exchange. The system is able to use the company’s existing base of knowledge and to push the manufacturing knowledge higher up into the design chain to reduce the need for costly and time consuming reworks and engineering changes. The design environment uses a knowledge based system Protégé and enables data/knowledge exchange through International Standards for Product Model Exchange (ISO STEP) and the Resource Description Framework
A Pedagogical Application Framework for Synchronous Collaboration
Designing successful collaborative learning activities is a new focus of research within the E-Learning community. The social dimension inside the traditional face-to-face collaborative learning is important and must be included in the online learning designs. In this thesis, we introduce the concept of Pedagogical Application Frameworks, and describe Beehive, a pedagogical application framework for synchronous collaborative learning. Beehive guides teachers in reusing online collaborative learning activities based on well-known pedagogical designs, to accomplish their educational objectives within a certain educational setting, and also simplifies the development of new pedagogical collaboration designs. Beehive’s conceptual model has four abstraction layers: Pedagogical Techniques, Collaboration Task patterns, CSCL Components, and CSCL script. By following the framework’s guidelines and specifications, developers will place the control of designing pedagogical collaboration tools in the teacher’s hand rather than in the software designer’s
A Touch of Evil: High-Assurance Cryptographic Hardware from Untrusted Components
The semiconductor industry is fully globalized and integrated circuits (ICs)
are commonly defined, designed and fabricated in different premises across the
world. This reduces production costs, but also exposes ICs to supply chain
attacks, where insiders introduce malicious circuitry into the final products.
Additionally, despite extensive post-fabrication testing, it is not uncommon
for ICs with subtle fabrication errors to make it into production systems.
While many systems may be able to tolerate a few byzantine components, this is
not the case for cryptographic hardware, storing and computing on confidential
data. For this reason, many error and backdoor detection techniques have been
proposed over the years. So far all attempts have been either quickly
circumvented, or come with unrealistically high manufacturing costs and
complexity.
This paper proposes Myst, a practical high-assurance architecture, that uses
commercial off-the-shelf (COTS) hardware, and provides strong security
guarantees, even in the presence of multiple malicious or faulty components.
The key idea is to combine protective-redundancy with modern threshold
cryptographic techniques to build a system tolerant to hardware trojans and
errors. To evaluate our design, we build a Hardware Security Module that
provides the highest level of assurance possible with COTS components.
Specifically, we employ more than a hundred COTS secure crypto-coprocessors,
verified to FIPS140-2 Level 4 tamper-resistance standards, and use them to
realize high-confidentiality random number generation, key derivation, public
key decryption and signing. Our experiments show a reasonable computational
overhead (less than 1% for both Decryption and Signing) and an exponential
increase in backdoor-tolerance as more ICs are added
Reusability in manufacturing, supported by value net and patterns approaches
The concept of manufacturing and the need or desire to create artefacts or products is
very, very old, yet it is still an essential component of all modem economies. Indeed,
manufacturing is one of the few ways that wealth is created. The creation or
identification of good quality, sustainable product designs is fundamental to the
success of any manufacturing enterprise. Increasingly, there is also a requirement for
the manufacturing system which will be used to manufacture the product, to be
designed (or redesigned) in parallel with the product design. Many different types of
manufacturing knowledge and information will contribute to these designs. A key
question therefore for manufacturing companies to address is how to make the very
best use of their existing, valuable, knowledge resources.
[…] The research reported in this thesis examines ways of reusing existing manufacturing
knowledge of many types, particularly in the area of manufacturing systems design.
The successes and failures of reported reuse programmes are examined, and lessons
learnt from their experiences. This research is therefore focused on identifying
solutions that address both technical and non-technical requirements simultaneously,
to determine ways to facilitate and increase the reuse of manufacturing knowledge in
manufacturing system design. [Continues.
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