In this paper is proposed a proposed control system for optimising the transmission power in cellular phones. As the mobile station moves toward the edge of a cell, the cell's base station notes that the signal st...
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In this paper is proposed a proposed control system for optimising the transmission power in cellular phones. As the mobile station moves toward the edge of a cell, the cell's base station notes that the signal strength is diminishing. Meanwhile, the base station in the cell the mobile station is moving toward (which is listening and measuring signal strength on all frequencies, not just its own one) sees the phone's signal strength increasing. The two base stations coordinate with each other, and at some point, the phone gets a signal on a control channel telling it to change frequencies. This hand off switches the phone to a different cell, which receives the signal with a bigger intensity, so the next decrement of the transmission power will be the lower possible without risking the quality of the transmission. Nowadays the central cellular controls the transmission power on the mobile station, on intervals of 4 dbs to increase or decrease it, so the final power always is above or under the required power.
Personalized hypermedia and Web systems are confronted with the challenge of inferring complex user traits like knowledge or preferences from very basic data like the 'clickstream' or ordinal-scale ratings. In...
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Personalized hypermedia and Web systems are confronted with the challenge of inferring complex user traits like knowledge or preferences from very basic data like the 'clickstream' or ordinal-scale ratings. In consequence, the resulting user models are only approximations that must be subject to continuous revision. Nonetheless, knowledge revision procedures are rarely made explicit in existing adaptive systems and models. In this paper, we sketch a frame-work for user modeling structured around revision and refutation of provisional conjectures drawn from basic data. This model can be used as a reference framework for the evaluation of the adequacy of the inferences carried out by existing adaptive hypermedia systems. Additionally, a number of existing adaptive systems is reviewed according to the core concepts of this model. It is also argued that Possibility Theory can be used to generalize different forms of uncertainty that are not precisely justified in existing applications.
By increasing the velocity of flow in coarse grain materials, local turbulences are often imposed to the flow. As a result, the flow regime through rockfill structures deviates from linear Darcy law; and nonlinear or ...
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By increasing the velocity of flow in coarse grain materials, local turbulences are often imposed to the flow. As a result, the flow regime through rockfill structures deviates from linear Darcy law; and nonlinear or non-Darcy flow equations will be applicable. Even though the structures of these nonlinear equations have some physical justifications, they still need empirical studies to estimate parameters of these equations. Hence there is a great deal of uncertainty as an inherent part of the estimation process. In this paper we investigate fuzzy systems paradigm to combine three of the most commonly validated and utilized empirical solutions in the current literature. In this way, the results of the three empirical equations serve as inputs, and the combination framework serve as fusion algorithm. The results show that when learning injected to fuzzy logic based models, the system provides a powerful solution with a strong ability to track reality. Specifically, this paper concludes that ANFIS provide accurate combination framework with greatest performance among the considered conventional alternatives as well as Mamdani structures.
Cooperative learning in multi-agent systems is generally expected to improve both quality and speed of learning. This is particularly true when agents are able to recognize expert agents amongst themselves and integra...
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Cooperative learning in multi-agent systems is generally expected to improve both quality and speed of learning. This is particularly true when agents are able to recognize expert agents amongst themselves and integrate their knowledge properly. Additionally, the process of learning can be improved when the reinforcement learning signals in each agent can balance between searching behavior of the unknown knowledge (exploration) and learning behavior of the obtained knowledge (exploitation). In this paper, a fuzzy dynamic cooperative learning method, based on weighted strategy sharing (WSS), is introduced which draws a balance between exploitation and exploration behaviors. In the weighed strategy sharing method, agents share their learned knowledge by a measure of their expertness. The strategy, when applied to the classic herding problem, shows further improvement in quality and speed of learning when parameters of the learning algorithm are dynamically determined by a fuzzy routine.
We present a swarm intelligence approach to data clustering. Data is clustered without initial knowledge of the number of clusters. Ant based clustering is used to initially create raw clusters and then these clusters...
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We present a swarm intelligence approach to data clustering. Data is clustered without initial knowledge of the number of clusters. Ant based clustering is used to initially create raw clusters and then these clusters are refined using the Fuzzy C Means algorithm. Initially the ants move the individual objects to form heaps. The centroids of these heaps are taken as the initial cluster centers and the Fuzzy C Means algorithm is used to refine these clusters. In the second stage the objects obtained from the Fuzzy C Means algorithm are hardened according to the maximum membership criteria to form new heaps. These new heaps are then sometimes moved and merged by the ants. The final clusters formed are refined by using the Fuzzy C Means algorithm. Results from three small data sets show that the partitions produced are competitive with those obtained from FCM.
Geospatial databases generally consist of measurements related to points (or pixels in the case of raster data), lines, and polygons. In recent years, the size and complexity of these databases have increased signific...
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Geospatial databases generally consist of measurements related to points (or pixels in the case of raster data), lines, and polygons. In recent years, the size and complexity of these databases have increased significantly and they often contain duplicate records, i.e., two or more close records representing the same measurement result. In this paper, we use fuzzy measures to address the problem of detecting duplicates in a database consisting of point measurements. As a test case, we use a database of measurements of anomalies in the Earth's gravity field that we have compiled. We show that a natural duplicate deletion algorithm requires (in the worst case) quadratic time, and we propose a new asymptotically optimal O(n/spl middot/log(n)) algorithm. These algorithms have been successfully applied to gravity databases. We believe that they will prove to be useful when dealing with many other types of point data.
This paper presents a survey of existing event systems structured as a taxonomy of distributed event-based programming systems. Our taxonomy identifies a set of fundamental properties of event-based programming system...
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ISBN:
(纸本)0769515886
This paper presents a survey of existing event systems structured as a taxonomy of distributed event-based programming systems. Our taxonomy identifies a set of fundamental properties of event-based programming systems and categorizes them according to the event model and event service criteria. The event service is further classified according to its organization and interaction model, as well as other functional and non-functional features.(1).
The Hololanguage (briefly, Holo) is a programming language derived from a new software development paradigm, the Holoparadigm. This paper provides an initial treatment to the problem of supporting the debug process of...
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ISBN:
(纸本)0769518672
The Hololanguage (briefly, Holo) is a programming language derived from a new software development paradigm, the Holoparadigm. This paper provides an initial treatment to the problem of supporting the debug process of Holoprograms. To this end, an extension is proposed to the Holoplatform, the Holo Extension for Debugging (HED). Finally, the Holo Debugger a simple debugger is presented to illustrate the feasibility of the proposed extension.
We focus on an important problem it? the space of ubiquitous computing, namely, programming support for the distributed heterogeneous computing elements that make up this environment. We address the interactive, dynam...
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ISBN:
(纸本)0769515851
We focus on an important problem it? the space of ubiquitous computing, namely, programming support for the distributed heterogeneous computing elements that make up this environment. We address the interactive, dynamic, and stream-oriented nature of this application class and develop appropriate computational abstractions in the D-Stampede distributed programming system. The key features of D-Stampede include indexing data streams temporally, correlating different data streams temporally, performing automatic distributed garbage collection of unnecessary stream data, supporting high performance by exploiting hardware parallelism where available, supporting platform and language heterogeneity, and dealing with application level dynamism. We discuss the features of D-Stampede, the programming ease it affords, and its performance.
Just like Remote Procedure Call (RPC) turned out to be a very effective OS abstraction in building client-server applications over LANs, Type-based Publish-Subscribe (TPS) can be viewed as a high-level candidate abstr...
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ISBN:
(纸本)0769515851
Just like Remote Procedure Call (RPC) turned out to be a very effective OS abstraction in building client-server applications over LANs, Type-based Publish-Subscribe (TPS) can be viewed as a high-level candidate abstraction for building Peer-to-Peer (P2P) applications over WANs. This paper relates our preliminary, though positive, experience of implementing and using TPS over JXTA, which can be viewed as the P2P counterpart to sockets. We show that, at least for P2P applications with the Java type model, TPS provides a high-level programming support that ensures type safety and encapsulation, without hampering the decoupled nature of these applications. Furthermore, the loss of flexibility (inherent to the use of any high level abstraction) and the performance overhead, are negligible with respect to the simplicity gained by using TPS.
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