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Research Collection School Of Computing and Information Systems

2000

Articles 1 - 29 of 29

Full-Text Articles in Physical Sciences and Mathematics

Collaborative Model And Algorithms For Supporting Real-Time Distribution Logistics Systems, Hoong Chuin Lau, Qi Zhang Liu Dec 2000

Collaborative Model And Algorithms For Supporting Real-Time Distribution Logistics Systems, Hoong Chuin Lau, Qi Zhang Liu

Research Collection School Of Computing and Information Systems

We study a complex optimization problem that arises due to an emerging trend in distribution logistics. The problem involves the integration of an inventory management problem and the vehicle routing problem with time windows, both of which are known to be NP-hard. We describe a collaborative approach to solve this problem in real-time. The novelty of our approach lies in the tight algorithmic integration between two sub-problems, and suggests an elegant scheme to deal with other integrated optimization problems of the same nature. For first sub-problem, we will present two algorithms: a complete mathematical model integrating integer programming with constraint …

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An Efficient And Practical Scheme For Privacy Protection In E-Commerce Of Digital Goods, Feng Bao, Robert H. Deng, Peirong Feng Dec 2000

An Efficient And Practical Scheme For Privacy Protection In E-Commerce Of Digital Goods, Feng Bao, Robert H. Deng, Peirong Feng

Research Collection School Of Computing and Information Systems

It is commonly acknowledged that customers’ privacy in electronic commerce should be well protected. The solutions may come not only from the ethics education and legislation, but also from cryptographic technologies. In this paper we propose and analyze a privacy protection scheme for e-commerce of digital goods. The scheme takes cryptography as its technical means to realize privacy protection for online customers. It is efficient in both computational cost and communication cost. It is very practical for real e-commerce systems compared with previous solutions. The cryptographic technique presented in this paper is rather simple. But the scheme has great application …

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Generalized Tcp Congestion Avoidance And Its Effect On Bandwidth Sharing And Variability, Archan Misra, John Baras, Teunis Ott Dec 2000

Generalized Tcp Congestion Avoidance And Its Effect On Bandwidth Sharing And Variability, Archan Misra, John Baras, Teunis Ott

Research Collection School Of Computing and Information Systems

To model possible suggested changes in TCP window adaptation in response to randomized feedback, such as ECN (explicit congestion notification), we formulate a generalized version of the TCP congestion avoidance algorithm. We first consider multiple such generalized TCP flows sharing a bottleneck buffer under the assured service model and use a fixed point technique to obtain the mean window sizes and throughputs for the TCP flows, To further study how changes in the adaptation algorithm affect the variability in the throughput, we use an analytical-cum-numerical technique to derive the window distribution (and related statistics) of a single generalized flow under …

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Extensible Mpeg-4 Textual Format (Xmt), Michelle Kim, Steve Wood, Lai-Tee Cheok Nov 2000

Extensible Mpeg-4 Textual Format (Xmt), Michelle Kim, Steve Wood, Lai-Tee Cheok

Research Collection School Of Computing and Information Systems

This paper describes the Extensible MPEG-4 Textual format (XMT), a framework for representing MPEG-4 scene description using a textual syntax. The XMT allows the content authors to exchange their content with other authors, tools or service providers, and facilitates interoperability with both the X3D, developed by the Web3D consortium, and the Synchronized Multimedia Integration Language (SM1L) from the W3C consortium.

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Using 'Drop-Biasing' To Stabilize The Occupancy Of Random-Drop Queues With Tcp Traffic, Archan Misra, Teunis Ott, John Baras Nov 2000

Using 'Drop-Biasing' To Stabilize The Occupancy Of Random-Drop Queues With Tcp Traffic, Archan Misra, Teunis Ott, John Baras

Research Collection School Of Computing and Information Systems

The paper describes how the use of ‘drop-biasing’, a technique to control the distribution of the gap between consecutive packet losses in random drop queues (such as RED) can be used to reduce the variability of the queue occupancy with TCP traffic. Reducing the variance of the queue occupancy reduces delay jitter for buffered packets, as well as decreases the likelihood of buffer underflow. We find that modifying the packet drop probabilities to ensure a minimum separation between consecutive packet drops serves to decrease the variability in the queue occupancy. This is really achieved as a result of the increased …

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Side Collision Warning System For Transit Buses, Sue Mcneil, David Duggins, Christoph Mertz, Arne Suppe, Chuck Thorpe Oct 2000

Side Collision Warning System For Transit Buses, Sue Mcneil, David Duggins, Christoph Mertz, Arne Suppe, Chuck Thorpe

Research Collection School Of Computing and Information Systems

Transit buses are involved in many more accidents than other vehicles. Collision warning systems (CWS) are therefore placed most efficiently on these buses. In our project, we investigate their operating environment and available technologies to develop performance specifications for such CWS. The paper discusses our findings of transit buses driving through very cluttered surroundings and being involved in many different types of accidents where currently available CWS no not work effectively. One of the focuses of our work is pedestrians around the bus and their detection.

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Motion-Based Video Representation For Scene Change Detection, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang, Roland T. Chin Sep 2000

Motion-Based Video Representation For Scene Change Detection, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang, Roland T. Chin

Research Collection School Of Computing and Information Systems

We present a new ly developed scheme for automatical ly partitioning videos into scenes. A scene is general ly referred to as a group of shots taken place in the same site. In this paper, we first propose a motion annotation algorithm based on the analysis of spatiotemporal image volumes. The algorithm characterizes the motions within shots by extracting and analyzing the motion trajectories encoded in the temporal slices of image volumes. A motion-based keyframe computing and selection strategy is thus proposed to compactly represent the content of shots. With these techniques, we further present a scene change detection algorithm …

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Telemip: Telecommunications-Enhanced Mobile Ip Architecture For Fast Intradomain Mobility, Subir Das, Archan Misra, Prathima Agrawal, Sajal K. Das Aug 2000

Telemip: Telecommunications-Enhanced Mobile Ip Architecture For Fast Intradomain Mobility, Subir Das, Archan Misra, Prathima Agrawal, Sajal K. Das

Research Collection School Of Computing and Information Systems

This article first surveys existing protocols for supporting IP mobility and then proposes an extension to the mobile IP architecture, called TeleMIP. Our architecture attempts to achieve smaller handoff latency by localizing the scope of most location update messages within an administrative domain or a geographical region. TeleMIP is intended for use in evolving third-generation wireless networks, and introduces a new logical entity, called the mobility agent, which provides a mobile node with a stable point of attachment in a foreign network. While the MA is functionally similar to conventional foreign agents, it is located at a higher level in …

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Cryptanalysis Of The M-Permutation Protection Schemes, Hongjun Wu, Feng Bao, Dingfeng Ye, Robert H. Deng Jul 2000

Cryptanalysis Of The M-Permutation Protection Schemes, Hongjun Wu, Feng Bao, Dingfeng Ye, Robert H. Deng

Research Collection School Of Computing and Information Systems

Anderson and Kuhn have proposed the EEPROM modification attack to recover the secret key stored in the EEPROM. At ACISP ’98, Fung and Gray proposed an m-permutation protection scheme against the EEPROM modification attack. At ACISP ’99, Fung and Gray pointed out that in their original scheme, a secret key with too small or too large Hamming weight could be recovered easily. Then they proposed a revised m- permutation protection scheme and claimed that their revised scheme does not leak any information of the secret key. In this paper, we break completely both the original and the revised …

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Multicast Internet Protocol, X. K. Wang, Robert H. Deng, Feng Bao Jun 2000

Multicast Internet Protocol, X. K. Wang, Robert H. Deng, Feng Bao

Research Collection School Of Computing and Information Systems

In this paper, we first review the existing IPv4 based multicast protocols and identify their shortcomings. We then proposed a new multicast protocol, called Multicast Internet Protocol (MIP), which is both scalable and flexible. The design principle of MIP is fundamentally different from the existing IPv4 based multicast protocols. The issues related to MIP routing and implementations are also studied in this paper.

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Justifying Electronic Banking Network Expansion Using Real Option Pricing: An Empirical Illustration, Michel Benaroch, Robert J. Kauffman Jun 2000

Justifying Electronic Banking Network Expansion Using Real Option Pricing: An Empirical Illustration, Michel Benaroch, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

The application of real options analysis to information technology investment evaluation problems recently has been proposed in the IS literature (Chalasani et al. 1997; Dos Santos 1991; Kambil et al. 1993; Kumar 1996; Taudes 1998). The research reported on in this paper illustrates the value of applying real options analysis in the context of a case study involving the deployment of point-of-sale (POS) debit services by the Yankee 24 shared electronic banking network of New England. In the course of so doing, the paper also attempts to operationalize real options analysis concepts by examining claimed strengths of this analysis approach …

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Re-Engineering Structures From Web Documents, Moh Chuang Hue, Ee Peng Lim, Wee-Keong Ng Jun 2000

Re-Engineering Structures From Web Documents, Moh Chuang Hue, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

To realize a wide range of applications (including digital libraries) on the Web, a more structured way of accessing the Web is required and such requirement can be facilitated by the use of XML standard. In this paper, we propose a general framework for reverse engineering (or re-engineering) the underlying structures i.e.,the DTD from a collection of similarly structured XML documents when they share some common but unknown DTDs. The essential data structures and algorithms for the DTD generation have been delveloped and experiments on real Web collections have been conducted to demonstrate their feasibilty. In addition, we also proposed …

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Dtd-Miner: A Tool For Mining Dtds From Xml Documents, Moh Chuang Hue, Ee Peng Lim, Wee-Keong Ng Jun 2000

Dtd-Miner: A Tool For Mining Dtds From Xml Documents, Moh Chuang Hue, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

XML documents are semistructured and the structure of the documents is embedded in the tags. Although XML documents can be accompanied by a DTD that defines the structure of the documents, the presence of a DTD is not mandatory. The difficulty in deriving the DTD for XML documents lies in the fact that DTDs are of different syntax as XML and that prior knowledge of the structure of the documents is required. In this paper, we introduce DTD-Miner, an automatic structure-mining tool for XML documents. Using a Web-based interface, the user will be able to submit a set of similarly …

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Motion Characterization By Temporal Slices Analysis, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang, Roland T. Chin Jun 2000

Motion Characterization By Temporal Slices Analysis, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang, Roland T. Chin

Research Collection School Of Computing and Information Systems

This paper describes an approach to characterize camera and object motions based on the analysis of spatio temporal image volumes. In the spatio-temporal slices of image volumes, motion is depicted as oriented patterns. We propose a tensor histogram computation algorithm to represent these oriented patterns. The motion trajectories in a histogram are tracked to describe both the camera and object motions. In addition, we exploit the similarity of the temporal slices in a volume to reliably partition a volume into motion tractable units.

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Decision Support Methods In Diabetic Patient Management By Insulin Administration Neural Network Vs. Induction Methods For Knowledge Classification, B. V. Ambrosiadou, S. Vadera, Venky Shankaraman, D. Goulis, G. Gogou May 2000

Decision Support Methods In Diabetic Patient Management By Insulin Administration Neural Network Vs. Induction Methods For Knowledge Classification, B. V. Ambrosiadou, S. Vadera, Venky Shankaraman, D. Goulis, G. Gogou

Research Collection School Of Computing and Information Systems

Diabetes mellitus is now recognised as a major worldwide public health problem. At present, about 100 million people are registered as diabetic patients. Many clinical, social and economic problems occur as a consequence of insulin-dependent diabetes. Treatment attempts to prevent or delay complications by applying ‘optimal’ glycaemic control. Therefore, there is a continuous need for effective monitoring of the patient. Given the popularity of decision tree learning algorithms as well as neural networks for knowledge classification which is further used for decision support, this paper examines their relative merits by applying one algorithm from each family on a medical problem; …

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Load Sharing In Distributed Multimedia-On-Demand Systems, Y. C. Tay, Hwee Hwa Pang May 2000

Load Sharing In Distributed Multimedia-On-Demand Systems, Y. C. Tay, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

Service providers have begun to offer multimedia-on-demand services to residential estates by installing isolated, small-scale multimedia servers at individual estates. Such an arrangement allows the service providers to operate without relying on a highspeed, large-capacity metropolitan area network, which is still not available in many countries. Unfortunately, installing isolated servers can incur very high server costs, as each server requires spare bandwidth to cope with fluctuations in user demand. The authors explore the feasibility of linking up several small multimedia servers to a (limited-capacity) network, and allowing servers with idle retrieval bandwidth to help out servers that are temporarily overloaded; …

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Predictive Adaptive Resonance Theory And Knowledge Discovery In Databases, Ah-Hwee Tan, Hui-Shin Vivien Soon May 2000

Predictive Adaptive Resonance Theory And Knowledge Discovery In Databases, Ah-Hwee Tan, Hui-Shin Vivien Soon

Research Collection School Of Computing and Information Systems

This paper investigates the scalability of predictive Adaptive Resonance Theory (ART) networks for knowledge discovery in very large databases. Although predictive ART performs fast and incremental learning, the number of recognition categories or rules that it creates during learning may become substantially large and cause the learning speed to slow down. To tackle this problem, we introduce an on-line algorithm for evaluating and pruning categories during learning. Benchmark experiments on a large scale data set show that on-line pruning has been effective in reducing the number of the recognition categories and the time for convergence. Interestingly, the pruned networks also …

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Jotmail: A Voicemail Interface That Enables You To See What Was Said, Steve Whittaker, Richard C. Davis, Julia Hirschberg, Urs Muller Apr 2000

Jotmail: A Voicemail Interface That Enables You To See What Was Said, Steve Whittaker, Richard C. Davis, Julia Hirschberg, Urs Muller

Research Collection School Of Computing and Information Systems

Voicemail is a pervasive, but under-researched tool for workplace communication. Despite potential advantages of voicemail over email, current phone-based voicemail UIs are highly problematic for users. We present a novel, Web-based, voicemail interface, Jotmail. The design was based on data from several studies of voicemail tasks and user strategies. The GUI has two main elements: (a) personal annotations that serve as a visual analogue to underlying speech; (b) automatically derived message header information. We evaluated Jotmail in an 8-week field trial, where people used it as their only means for accessing voicemail. Jotmail was successful in supporting most key voicemail …

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A Framework For Acquiring Domain Semantics And Knowledge For Database Integration, Roger Hsiang-Li Chiang, Ee Peng Lim, Veda C. Storey Mar 2000

A Framework For Acquiring Domain Semantics And Knowledge For Database Integration, Roger Hsiang-Li Chiang, Ee Peng Lim, Veda C. Storey

Research Collection School Of Computing and Information Systems

Database integration research has traditionally focused on understanding integration issues from the schema and instance perspectives. As a result, database integration approaches tend to rely on a direct comparison of schema and instance elements. However, when the integration of heterogeneous databases is performed without considering the domain semantics and knowledge of local databases such as context information and requirement specifications, an incorrect integrated database may be produced. In this research, a framework for carrying out database integration tasks using the above knowledge is proposed. The framework provides a thorough foundation to: 1. analyze database integration issues from a broad scope, …

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Solving A Supply Chain Optimization Problem Collaboratively, Hoong Chuin Lau, A. L. C. Lim, Q Liu Jan 2000

Solving A Supply Chain Optimization Problem Collaboratively, Hoong Chuin Lau, A. L. C. Lim, Q Liu

Research Collection School Of Computing and Information Systems

We propose a novel algorithmic framework to solve an integrated planning and scheduling problem in supply chain management. This problem involves the integration of an inventory management problem and the vehicle routing problem with time windows, both of which are known to be NP-hard. Under this framework, algorithms that solve the underlying sub-problems collaborate rigorously yet in a computationally efficient manner to arrive at a good solution. We will then present two algorithms to solve the inventory management problem: a complete mathematical model integrating integer programming with constraint programming, and an incomplete algorithm based on tabu search. We present experimental …

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Measurement Of The Z Resonance Parameters At Lep, R. Barate, M. Thulasidas Jan 2000

Measurement Of The Z Resonance Parameters At Lep, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The properties of the Z resonance are measured from the analysis of 4.5 million Z decays into fermion pairs collected with the ALEPH detector at LEP. The data are consistent with lepton universality. The resonance parameters are measured to be MZ=(91.1885±0.0031)GeV/c2MZ=(91.1885±0.0031)GeV/c2, ΓZ=(2.4951±0.0043)ΓZ=(2.4951±0.0043) GeV, σ0had=(41.559±0.058)σhad0=(41.559±0.058) nb and, combining the three lepton flavours, Rℓ=20.725±0.039Rℓ=20.725±0.039. The corresponding number of light neutrino species is Nν=2.983±0.013Nν=2.983±0.013 and the strong coupling constant is αs(MZ)=0.114±0.004±0.002QCD+0.005log10[MH150GeV/c2]αs(MZ)=0.114±0.004±0.002QCD+0.005log10⁡[MH150GeV/c2]. The lepton pair forward-backward asymmetry is measured to be A0,ℓFB=0.0173±0.0016AFB0,ℓ=0.0173±0.0016 from which the effective weak mixing angle is derived: sin2θlepteff=0.23089±0.00089sin2⁡θefflept=0.23089±0.00089. The measurement of the leptonic width Γℓℓ=84.02±0.15Γℓℓ=84.02±0.15 MeV leads to a determination …

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Some Remarks On Fair Exchange Protocol, Jianying Zhou, Robert H. Deng, Feng Bao Jan 2000

Some Remarks On Fair Exchange Protocol, Jianying Zhou, Robert H. Deng, Feng Bao

Research Collection School Of Computing and Information Systems

Fair exchange turns out to be an increasingly important topic due to the rapid growth of electronic commerce. An exchange is deemed to be fair if at the end of exchange, either each party receives the expected item or neither party receives any useful information about the other’s item. Several protocols for fair exchange have been proposed in recent years. In this paper, we first examine a newly published fair exchange protocol and point out its flaws and weaknesses. We then put forward a more efficient and secure protocol and give an informal analysis.

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Study Of Charm Production In Z Decays, R. Barate, M. Thulasidas Jan 2000

Study Of Charm Production In Z Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The production rates of D∗±D∗±, D∗±sDs∗±, D±D±, D0/D¯0D0/D¯0, D±sDs±, and Λ+c/Λ¯−cΛc+/Λ¯c− in Z→cc¯Z→cc¯ decays are measured using the LEP I data sample recorded by the ALEPH detector. The fractional energy spectrum of the D∗±D∗± is well described as the sum of three contributions: charm hadronisation, b hadron decays and gluon splitting into a pair of heavy quarks. The probability for a c quark to hadronise into a D∗+D∗+ is found to be f(c→D∗+)=0.233±0.010(stat.)±0.011(syst.)f(c→D∗+)=0.233±0.010(stat.)±0.011(syst.). The average fraction of the beam energy carried by D∗±D∗± mesons in Z→cc¯Z→cc¯ events is measured to be ⟨XE(D∗±)⟩cc¯=0.4878±0.0046(stat.)±0.0061(syst.).⟨XE(D∗±)⟩cc¯=0.4878±0.0046(stat.)±0.0061(syst.). The D∗±D∗± energy and the hemisphere mass imbalance …

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Inclusive Production Of Π0, Η, Η′ (958), Kg0s And Λ In Two- And Three-Jet Events From Hadronic Z Decays, R. Barate, M. Thulasidas Jan 2000

Inclusive Production Of Π0, Η, Η′ (958), Kg0s And Λ In Two- And Three-Jet Events From Hadronic Z Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The production rates and the inclusive cross sections of the isovector meson π0π0, the isoscalar mesons ηη and η′(958)η′(958), the strange meson K0SKS0 and the ΛΛ baryon have been measured as functions of scaled energy in hadronic events, two-jet events and each jet of three-jet events from hadronic Z decays and compared to Monte Carlo models. The analysis is based on 3.7 million hadronic events collected with the ALEPH detector at LEP at a centre-of-mass energy of s√=91.2s=91.2 GeV. The JETSET modelling of the gluon fragmentation into isoscalar mesons is found to be in agreement with the experimental results. HERWIG …

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Measurements Of The Structure Of Quark And Gluon Jets In Hadronic Z Decays, R. Barate, M. Thulasidas Jan 2000

Measurements Of The Structure Of Quark And Gluon Jets In Hadronic Z Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

An experimental investigation of the structure of identified quark and gluon jets is presented. Observables related to both the global and internal structure of jets are measured; this allows for tests of QCD over a wide range of transverse momentum scales. The observables include distributions of jet-shape variables, the mean and standard deviation of the subjet multiplicity distribution and the fragmentation function for charged particles. The data are compared with predictions of perturbative QCD as well as QCD-based Monte Carlo models. In certain kinematic regions the measurements are sensitive mainly to perturbatively calculable effects, allowing for a test of QCD. …

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The Integration Of Relationship Instances From Heterogeneous Databases, Ee Peng Lim, Roger Hsiang-Li Chiang Jan 2000

The Integration Of Relationship Instances From Heterogeneous Databases, Ee Peng Lim, Roger Hsiang-Li Chiang

Research Collection School Of Computing and Information Systems

In the process of integrating legacy databases, one has to resolve inter-database conflicts at both the schema and instance levels. In this paper, we discuss relationship conflicts as a special type of conflicts to be resolved during the database integration. Relationships are properties that relate real world objects. So far, most inter-database relationship conflicts are addressed at the schema-level by various schema integration techniques. However, instance-level relationship conflicts are largely neglected. This paper therefore investigates the causes of instance-level relationship conflicts and proposes a taxonomy for classifying instance-level relationship conflicts. In addition, we develop a systematic process to resolve instance-level …

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Supervised Adaptive Resonance Theory And Rules, Ah-Hwee Tan Jan 2000

Supervised Adaptive Resonance Theory And Rules, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Supervised Adaptive Resonance Theory is a family of neural networks that performs incremental supervised learning of recognition categories (pattern classes) and multidimensional maps of both binary and analog patterns. This chapter highlights that the supervised ART architecture is compatible with IF-THEN rule-based symbolic representation. Specifi­cally, the knowledge learned by a supervised ART system can be readily translated into rules for interpretation. Similarly, a priori domain knowl­edge in the form of IF-THEN rules can be converted into a supervised ART architecture. Not only does initializing networks with prior knowl­edge improve predictive accuracy and learning efficiency, the inserted symbolic knowledge can also …

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Search For R-Parity Violating Decays Of Supersymmetric Particles In E+E- Collisions At Centre-Of-Mass Energies Near 183 Gev, R. Barate, M. Thulasidas Jan 2000

Search For R-Parity Violating Decays Of Supersymmetric Particles In E+E- Collisions At Centre-Of-Mass Energies Near 183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

Searches for pair-production of supersymmetric particles under the assumption that R-parity is violated via a single dominant LLE¯LLE¯, LQD¯LQD¯ or U¯D¯D¯U¯D¯D¯ coupling are performed using the data collected by the ALEPH collaboration at centre-of-mass energies of 181–184 GeV. The observed candidate events in the data are in agreement with the Standard Model expectations. Upper limits on the production cross-sections and lower limits on the masses of charginos, sleptons, squarks and sneutrinos are derived.

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Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas Jan 2000

Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e−e+e− collisions at centre-of-mass energies from 130 to 183 GeV are presented. Results for e+e−e+e−, μ+μ−μ+μ−, τ+τ−τ+τ−, qq¯qq¯, bb¯bb¯ and cc¯cc¯ production show no significant deviation from the Standard Model predictions. This enables constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z′Z′ bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale ΛΛ of e+e−ff¯e+e−ff¯ contact interactions are typically in the range from 2 to 10 TeV. Limits on R-parity violating sneutrinos reach masses of a few …

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