In this paper, the issue of querying databases containing ill-known values is addressed. A new type of queries is introduced, based on criteria applying to the representations of ill-known data. In the regular possibi...
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A knowledge-based approach to retrieve medical images by feature and content with spatial and temporal constructs is developed. Selected objects of interest in a medical image (e.g. x-ray, MR image) are segmented, and...
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ISBN:
(纸本)3540636145
A knowledge-based approach to retrieve medical images by feature and content with spatial and temporal constructs is developed. Selected objects of interest in a medical image (e.g. x-ray, MR image) are segmented, and contours axe generated from these objects. Features (e.g. shape, size, texture) and content (e.g. spatial relationships among objects) are extracted and stored in a feature and content database. Knowledge about image features can be expressed as a hierarchical structure called a Type Abstraction Hierarchy (TAH). the high-level nodes in the TAH represent more general concepts than low-level nodes. thus, traversing along TAH nodes allows approximate matching by feature and content if an exact match is not available. TAHs can be generated automatically by clustering algorithms based on feature values in the databases and hence are scalable to large collections of image features. ~rther~ since TAHs are generated based on user classes and applications, they are context- and user-sensitive. A knowledge-based semantic image model is proposed which consists of four layers (raw data layer, feature and content layer, schema layer, and knowledge layer) to represent the various aspects of an image objects' characteristics. the model provides a mechanism for accessing and processing spatial, evolutionaxy, and temporal queries. A knowledge-based spatial temporal query language (KSTL) has developed which extends ODMG's OQL and supports approximate matching of feature and content, conceptual terms, and temporal logic predicates. Furthe,. a visual query language has been developed that accept pointclick- and-drag visual iconic input on the screen which is then translated into KSTL. User models are introduced to provide default parameter values for specifying query conditions. We have implemented a Knowledge-Based Medical database System (KMeD) at UCLA, and currently under evaluation by the medical staff. the results from this research should be applicable to other mult
Many different parallel languages and paradigms have been developed, each with its own advantages. To benefit from all of them, it should be possible to link together modules written in different parallel languages in...
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Many different parallel languages and paradigms have been developed, each with its own advantages. To benefit from all of them, it should be possible to link together modules written in different parallel languages in a single application. Since the paradigms sometimes differ in fundamental ways, this is difficult to accomplish. this paper describes a framework, Converse, that supports such multi-lingual interoperability. the framework is meant to be inclusive, and has been verified to support the SPMD programming style, message-driven programming, parallel object-oriented programming, and thread-based paradigms. the framework aims at extracting the essential aspects of the runtime support into a set of core components, so that language-specific code does not have to pay overhead for features that it does not need.
Fine-grained concurrent object-oriented programming (COOP) models can simplify the programming of irregular parallel applications but are often perceived as inefficient. In this paper, we study implementation techniqu...
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Fine-grained concurrent object-oriented programming (COOP) models can simplify the programming of irregular parallel applications but are often perceived as inefficient. In this paper, we study implementation techniques to obtain efficient parallel execution of fine-grained COOP languages using a medium-sized protein dynamics program. We found that even with high data locality and good sequential code efficiency, an implementation using only thread-oriented optimizations and software multithreading fails to achieve parallel efficiency. the two major sources of overhead are the lack of processor-level data reuse and fine-grained threads for remote object accesses. Two processor-oriented optimizations, processor-level caching and communication grouping, overcome these inefficiencies and achieve performance comparable to a highly-tuned SPMD program.
In many concurrent programminglanguages programs are difficult to extend and modify. this is because changes in a concurrent program (either through modification or extension) require re-implementation of some or all...
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In many concurrent programminglanguages programs are difficult to extend and modify. this is because changes in a concurrent program (either through modification or extension) require re-implementation of some or all components. this paper presents the design of a concurrent object-oriented programming language based upon separate specifications of computations and interactions of programs. Separate specification of computations and interactions allows each to be separately modified and extended. We show that separation also facilitates extension of other language composition mechanisms such as class, inheritance, and template in order to define concurrent program abstractions. the resulting language supports extensibility and modifiability of concurrent programs as well as reusability of specifications of computations and interactions.
Most parallel languages provide means to express parallelism, e.g. a parallel-do construct, but no means to terminate the parallel activities spawned by such constructs. We propose three high-level primitives for this...
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Most parallel languages provide means to express parallelism, e.g. a parallel-do construct, but no means to terminate the parallel activities spawned by such constructs. We propose three high-level primitives for this purpose, which are defined by analogies with primitives that break out of sequential iterative constructs. the primitives are pcontinue, which terminates the calling activity, pbreak, which terminates all the activities in the construct that spawned the calling activity, and return, which terminates all the activities created in the current function call. these constructs are especially useful in search problems, where an activity that finds a solution can terminate other activities that are investigating inferior approaches. Given that parallel constructs can be nested, activities form a tree rooted at the original activity that started the program. the main challenge in implementing pbreak and return is identifying the subtree of activities that should be killed. three algorithms were designed and implemented, and experiments show that using these constructs can provide significant performance benefits.
the proceedings contain 36 papers. the topics discussed include: application of domain analysis to object-oriented systems;applying object-oriented software engineering methods to the development of call center softwa...
ISBN:
(纸本)0897917219
the proceedings contain 36 papers. the topics discussed include: application of domain analysis to object-oriented systems;applying object-oriented software engineering methods to the development of call center software: a case study;using objects to manage in-memory data intensive expert systems;the navigation toolkit project revisited;performance of a OODB in a online 7x24x365 manufacturing operation;why C++ is not just an object-oriented programming language;patterns: cult to culture?;OOPSLA'95 doctoral symposium;implementing a real -time, embedded, telecommunication switching system in SmallTalk;object oriented project management;OO process and metrics for effort estimation;semantic integration in complex systems: collective behavior in business rules and software transactions;workshop on design patterns for concurrent, parallel and distributed object-oriented systems;the object engine: foundation for next generation architectures;subjectivity in object-oriented systems workshop summary;objects and relational databases;object database behavior, benchmarks, and performance workshop addendum;workshop on adaptable and adaptive software;and legacy systems and object technology workshop summary.
this paper describes developed computer code AIRA used to calculate the atmospheric transmittance with a low and medium spectral resolution in the visible and IR. three basic factors affecting the radiation attenuatio...
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ISBN:
(纸本)081941011X
this paper describes developed computer code AIRA used to calculate the atmospheric transmittance with a low and medium spectral resolution in the visible and IR. three basic factors affecting the radiation attenuation (molecular absorption, aerosol extinction, molecular scattering) are included. AIRA calculates molecular absorption, using a band model whose parameters are derived from molecular absorption parameters database. AIRA is used both as a traditional band model and a single-line model. the latter was formerly regarded only as a theoretical treatment. However, it provides a satisfactory agreement with experiments for some H2O and CO2 bands.
the authors discuss three different paradigms suitable for querying object-oriented geographic databases. All together, the paradigms presented constitute the basis of a flexible and easy to use querying environment s...
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ISBN:
(纸本)0818621338
the authors discuss three different paradigms suitable for querying object-oriented geographic databases. All together, the paradigms presented constitute the basis of a flexible and easy to use querying environment suitable for different categories of users. the first paradigm, to be adopted by programmer users, is based on the message sending mechanism of object-oriented databaseprogramminglanguages. the second paradigm is a browsing-based technique suitable for not unskilled users who have only a vague idea of the contents of the database. Finally, a frame-based approach is adopted for the third paradigm: this is suitable for non-programmer users who have a specific task to accomplish.
Progress on automated termination detection for logic programs is reported. the prospects for handling a large class of programs completely automatically appear promising, in contrast to the bleak picture for procedur...
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