Spelling suggestions: "subject:"communmunication ciences"" "subject:"communmunication csciences""
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Linking process quality with performance: an empirical study of New Zealand manufacturing plantsSluti, Donald George January 1992 (has links)
This study was conducted to assess the impacts of quality on operational and business performance in manufacturing firms. Data were provided by 184 diversified New Zealand manufacturing plants- Quality is defined as the degree of conformance to specifications. The first phase of the research was the construction of a theoretical model to incorporate the impacts of quality on manufacturing performance, manufacturing productivity and business performance. The relationships of the model are based on the quality management literature. The second phase of the research was the design and administration of a survey instrument for the collection of empirical performance data. The data were then used to evaluate the relationships represented in the model. The final phase of the research used structural equations modelling in order to evaluate the relationships of the model. Quality was found to have significant and positive impacts on operational performance measures for process utilization, process output, production costs, work-in-process inventory levels and on-time delivery rate. The analysis found that change in quality level was most strongly associated with change in process utilization. The findings for the impacts of quality on operational performance were compatible with the quality management literature. The impacts of quality on business performance given by structural equations analysis were significant and positive for productivity-induced improvements of quality. Generally, the support for the impacts of quality on business performance which occur through other aspects of, operational performance was not significant. The limitations of the study were specified. The implications of the findings of the study for manufacturers were reviewed, along with the directions for future research.
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The Design and Verification of a Cryptographic Security ArchitectureGutmann, Peter January 2000 (has links)
A cryptographic security architecture constitutes the collection of hardware and software which protects and controls the use of encryption keys and similar cryptovariables. This thesis presents a design for a portable, flexible high-security architecture based on a traditional computer security model. Behind the API it consists of a kernel implementing a reference monitor which controls access to security-relevant objects and attributes based on a configurable security policy. Layered over the kernel are various objects which abstract core functionality such as encryption and digital signature capabilities, certificate management and secure sessions and data enveloping (email encryption). The kernel itself uses a novel design which bases its security policy on a collection of filter rules enforcing a cryptographic module-specific security policy. Since the enforcement mechanism (&e kernel) is completely independent of the policy database (the filter rules), it is possible to change the behaviour of the architecture by updating the policy database without having to make any changes to the kernel itself. This clear separation of policy and mechanism contrasts with current cryptographic security architecture approaches which, if they enforce controls at all, hardcode them into the implementation, making it difficult to either change the controls to meet application-specific requirements or to assess and verify them. To provide assurance of the correctness of the implementation, this thesis presents a design and implementation process which has been selected to allow the implementation to be verified in a manner which can reassure an outsider that it does indeed function as required. In addition to producing verification evidence which is understandable to the average user, the verification process for an implementation needs to be fully automated and capable of being taken down to the level of running code, an approach which is currently impossible with traditional methods. The approach presented here makes it possible to perform verification at this level, something which had previously been classed as "beyond Al" (that is, not achievable using any known technology). The versatility of the architecture presented here has been proven through its use in implementations ranging from l6-bit microcontrollers through to supercomputers, as well as a number of unusual areas such as security modules in ATMs and cryptographic coprocessors for general-purpose computers. / Note: Updated version of the thesis now published as Gutmann, P (2004). Cryptographic security architecture: design and verification. New York: Springer. ISBN 9780387953876.
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Digital surface curvatureRugis, John January 2008 (has links)
The theoretical basis for this thesis can be found in the subject of differential geometry where both line and surface curvature is a core feature. We begin with a review of curvature basics, establish notational conventions, and contribute new results (on n-cuts) which are of importance for this thesis. A new scale invariant curvature measure is presented. Even though curvature of continuous smooth lines and surfaces is a well-defined property, when working with digital surfaces, curvature can only be estimated. We review the nature of digitized surfaces and present a number of curvature estimators, one of which (the 3-cut mean estimator) is new. We also develop an estimator for our new scale invariant curvature measure, and apply it to digital surfaces. Surface curvature maps are defined and examples are presented. A number of curvature visualization examples are provided. In practical applications, the noise present in digital surfaces usually precludes the possibility of direct curvature calculation. We address this noise problem with solutions including a new 2.5D filter. Combining techniques, we introduce a data processing pipeline designed to generate surface registration markers which can be used to identify correspondences between multiple surfaces. We present a method (projecting curvature maps) in which high resolution detail is merged with a simplified mesh model for visualization purposes. Finally, we present the results of experiments (using texture projection merging and image processing assisted physical measurement) in which we have identified, characterized, and produced visualizations of selected fine surface detail from a digitization of Michelangelo’s David statue.
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Multiple textual and graphical views for interactive software development environmentsGrundy, John (John Collis) January 1993 (has links)
Diagram construction can be used to visually analyse and design a complex software system using natural, graphical representations describing high-level structure and semantics. Textual programming can specify detailed documentation and functionality not well expressed at a visual level. Integrating multiple textual and graphical views of software development allows programmers to utilise both representations as appropriate. Consistency management between these views must be automatically maintained by the development environment. MViews, a model for such software development environments, has been developed. MViews supports integrated textual and graphical views of software development with consistency management. MViews provides flexible program and view representation using a novel object dependency graph approach. Multiple views of a program may contain common information and are stored as graphs with textual or graphical renderings and editing. Change propagation between program components and views is supported using a novel update record mechanism. Different editing tools are integrated as views of a common program repository and new program representations and editors can be integrated without affecting existing views. A specification language for program and view state and manipulation semantics, and a visual specification language for view appearance and editing semantics, have been developed. An object-oriented architecture based on MViews abstractions allows environment specifications to be translated into a design for implementing environments. Environment designs are implemented by specialising a framework of object-oriented language classes based on the MViews architecture. A new language is described which provides object-oriented extensions to Prolog. An integrated software development environment for this language is discussed and the specification, design and implementation of this environment using MViews are described. MViews has also been reused to produce a graphical entity-relationship/textual relational database schema modeller, a dialogue painter with a graphical editing view and textual constraints view, and various program visualisation systems.
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Enhancements to an object-oriented programming languageMugridge, Warwick Bruce January 1990 (has links)
The objective of this thesis has been to explore the value and limitations of Class, an object-oriented programming language, in order to further the development of the language. The pivot for this thesis is WallBrace, a code-checking system. The development of the WallBrace system is the basis of a critique of Class, and leads to a number of language extensions being proposed. An important aim in this work has been the careful integration of these enhancements with the rest of the language, avoiding unnecessary additions. A number of functional and object-oriented extensions to the language are proposed. Discrimination functions, which may be higher-order and polymorphic, add considerable functional power. Generic classes allow for abstract data types, such as sets and lists, to be defined within the language. The forms interface proposed will greatly enhance the quality of user interfaces to Class programs. An external interface will allow Class programs to communicate with files, databases, and specialist user-interface programs, such as for plan entry.
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Linking process quality with performance: an empirical study of New Zealand manufacturing plantsSluti, Donald George January 1992 (has links)
This study was conducted to assess the impacts of quality on operational and business performance in manufacturing firms. Data were provided by 184 diversified New Zealand manufacturing plants- Quality is defined as the degree of conformance to specifications. The first phase of the research was the construction of a theoretical model to incorporate the impacts of quality on manufacturing performance, manufacturing productivity and business performance. The relationships of the model are based on the quality management literature. The second phase of the research was the design and administration of a survey instrument for the collection of empirical performance data. The data were then used to evaluate the relationships represented in the model. The final phase of the research used structural equations modelling in order to evaluate the relationships of the model. Quality was found to have significant and positive impacts on operational performance measures for process utilization, process output, production costs, work-in-process inventory levels and on-time delivery rate. The analysis found that change in quality level was most strongly associated with change in process utilization. The findings for the impacts of quality on operational performance were compatible with the quality management literature. The impacts of quality on business performance given by structural equations analysis were significant and positive for productivity-induced improvements of quality. Generally, the support for the impacts of quality on business performance which occur through other aspects of, operational performance was not significant. The limitations of the study were specified. The implications of the findings of the study for manufacturers were reviewed, along with the directions for future research.
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The Design and Verification of a Cryptographic Security ArchitectureGutmann, Peter January 2000 (has links)
A cryptographic security architecture constitutes the collection of hardware and software which protects and controls the use of encryption keys and similar cryptovariables. This thesis presents a design for a portable, flexible high-security architecture based on a traditional computer security model. Behind the API it consists of a kernel implementing a reference monitor which controls access to security-relevant objects and attributes based on a configurable security policy. Layered over the kernel are various objects which abstract core functionality such as encryption and digital signature capabilities, certificate management and secure sessions and data enveloping (email encryption). The kernel itself uses a novel design which bases its security policy on a collection of filter rules enforcing a cryptographic module-specific security policy. Since the enforcement mechanism (&e kernel) is completely independent of the policy database (the filter rules), it is possible to change the behaviour of the architecture by updating the policy database without having to make any changes to the kernel itself. This clear separation of policy and mechanism contrasts with current cryptographic security architecture approaches which, if they enforce controls at all, hardcode them into the implementation, making it difficult to either change the controls to meet application-specific requirements or to assess and verify them. To provide assurance of the correctness of the implementation, this thesis presents a design and implementation process which has been selected to allow the implementation to be verified in a manner which can reassure an outsider that it does indeed function as required. In addition to producing verification evidence which is understandable to the average user, the verification process for an implementation needs to be fully automated and capable of being taken down to the level of running code, an approach which is currently impossible with traditional methods. The approach presented here makes it possible to perform verification at this level, something which had previously been classed as "beyond Al" (that is, not achievable using any known technology). The versatility of the architecture presented here has been proven through its use in implementations ranging from l6-bit microcontrollers through to supercomputers, as well as a number of unusual areas such as security modules in ATMs and cryptographic coprocessors for general-purpose computers. / Note: Updated version of the thesis now published as Gutmann, P (2004). Cryptographic security architecture: design and verification. New York: Springer. ISBN 9780387953876.
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Digital surface curvatureRugis, John January 2008 (has links)
The theoretical basis for this thesis can be found in the subject of differential geometry where both line and surface curvature is a core feature. We begin with a review of curvature basics, establish notational conventions, and contribute new results (on n-cuts) which are of importance for this thesis. A new scale invariant curvature measure is presented. Even though curvature of continuous smooth lines and surfaces is a well-defined property, when working with digital surfaces, curvature can only be estimated. We review the nature of digitized surfaces and present a number of curvature estimators, one of which (the 3-cut mean estimator) is new. We also develop an estimator for our new scale invariant curvature measure, and apply it to digital surfaces. Surface curvature maps are defined and examples are presented. A number of curvature visualization examples are provided. In practical applications, the noise present in digital surfaces usually precludes the possibility of direct curvature calculation. We address this noise problem with solutions including a new 2.5D filter. Combining techniques, we introduce a data processing pipeline designed to generate surface registration markers which can be used to identify correspondences between multiple surfaces. We present a method (projecting curvature maps) in which high resolution detail is merged with a simplified mesh model for visualization purposes. Finally, we present the results of experiments (using texture projection merging and image processing assisted physical measurement) in which we have identified, characterized, and produced visualizations of selected fine surface detail from a digitization of Michelangelo’s David statue.
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Multiple textual and graphical views for interactive software development environmentsGrundy, John (John Collis) January 1993 (has links)
Diagram construction can be used to visually analyse and design a complex software system using natural, graphical representations describing high-level structure and semantics. Textual programming can specify detailed documentation and functionality not well expressed at a visual level. Integrating multiple textual and graphical views of software development allows programmers to utilise both representations as appropriate. Consistency management between these views must be automatically maintained by the development environment. MViews, a model for such software development environments, has been developed. MViews supports integrated textual and graphical views of software development with consistency management. MViews provides flexible program and view representation using a novel object dependency graph approach. Multiple views of a program may contain common information and are stored as graphs with textual or graphical renderings and editing. Change propagation between program components and views is supported using a novel update record mechanism. Different editing tools are integrated as views of a common program repository and new program representations and editors can be integrated without affecting existing views. A specification language for program and view state and manipulation semantics, and a visual specification language for view appearance and editing semantics, have been developed. An object-oriented architecture based on MViews abstractions allows environment specifications to be translated into a design for implementing environments. Environment designs are implemented by specialising a framework of object-oriented language classes based on the MViews architecture. A new language is described which provides object-oriented extensions to Prolog. An integrated software development environment for this language is discussed and the specification, design and implementation of this environment using MViews are described. MViews has also been reused to produce a graphical entity-relationship/textual relational database schema modeller, a dialogue painter with a graphical editing view and textual constraints view, and various program visualisation systems.
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160 |
Enhancements to an object-oriented programming languageMugridge, Warwick Bruce January 1990 (has links)
The objective of this thesis has been to explore the value and limitations of Class, an object-oriented programming language, in order to further the development of the language. The pivot for this thesis is WallBrace, a code-checking system. The development of the WallBrace system is the basis of a critique of Class, and leads to a number of language extensions being proposed. An important aim in this work has been the careful integration of these enhancements with the rest of the language, avoiding unnecessary additions. A number of functional and object-oriented extensions to the language are proposed. Discrimination functions, which may be higher-order and polymorphic, add considerable functional power. Generic classes allow for abstract data types, such as sets and lists, to be defined within the language. The forms interface proposed will greatly enhance the quality of user interfaces to Class programs. An external interface will allow Class programs to communicate with files, databases, and specialist user-interface programs, such as for plan entry.
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