MIGRATION TO 4G- ìUBIQUITOUS BROADBANDî ECONOMIC MODELING OF WI-FI WITH WIMAX

Abstract: There are several ways by which a WISP (Wireless Internet Service Provider) can deliver broadband service. However, the service offered should be affordable to all classes of the society. There are numerous broadband business models proposed. It is necessary to figure out the profitable business case that best fit the WISP. We have no hesitation to say that Wi-Fi with WiMAX can be called as migration path to 4G when both are viewed as complementary to one another. It also has the potential to compete on a cost-per-megabyte level with both cable and DSL, and offer a cost effective solution. If engineering and economics is rightfully applied, a Wi-Fi network can be built around an entire city, instead of providing limited coverage at the hotspots. This paper focuses on the economic modeling of how to fit Wi-Fi hot zones into WiMAX infrastructure mesh and also addresses Voice over Wi-Fi (VoWi-Fi).
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Vinoth Gunasekaran, Dr. Fotios C. Harmantzis, Stevens Institute of Technology Telecommunications Management Castle Point on Hudson Hoboken, NJ 07030, USA {vgunasek, fharmant} @stevens.edu

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Interoperability in Future Wireless Communications Systems: A Roadmap to 4G

Abstract – Future generation communication systems will provide transparent and seamless user roaming with end-to-end QoS guarantees. As a result, the interoperability of various communicating platforms emerges as a crucial necessity. This paper gives an overview of the major 4G features and explains the significance of the network interoperability aspect and its role in the development towards the 4G paradigm.
Keywords – Interoperability, Reconfigurability, Wireless Systems, 4G.
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Liljana M. Gavrilovska and Vladimir M. Atanasovski are with the Faculty of Electrical Engineering and Information Technologies, University “Ss Cyril and Methodius”, Karpos 2 bb, 1000 Skopje, Macedonia, E-mail: liljana@feit.ukim.edu.mk, vladimir@feit.ukim.edu.mk

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4G MC-CDMA Multi Antenna System on Chip for Radio Enhancements (4MORE)

ABSTRACT
The IST project 4MORE will research and develop an innovative architecture suitable for the advanced signal processing techniques involved in MC-CDMA and employing multiple antennas. To achieve its target in terms of broadband capabilities, the design will include a specific RF front-end. It will implement advanced signal processing techniques such as space-time coding, array processing, multi-user detection, interference cancellation, synchronization, etc. to fully exploit the potentialities of Multiple Transmission Multiple Reception (MTMR) technology. In addition, it will develop enhanced L2 schemes for truly optimizing the bandwidth usage. Finally, the project will advance one step towards the feasibility of a 4G terminal, by integrating these new technologies in a cost effective, low power and integrated system-on-chip solution. 4MORE is an IST STREP project involving 11 partners. It started in January 2004, for a duration of 30 months.
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1German Aerospace Center (DLR), Germany, 2CEA/LETI, France, 3Institute of Electronics and Telecommunications of Rennes (IETR), France, 4Mitsubishi Electric ITE-TCL, France, 5Inst. Telecom. / Univ. Aveiro, Portugal, 6CCSR/ Univ. of Surrey, United Kingdom, 7ACORDE, Spain, 8STMicroelectronics, Switzerland, 9NOKIA, Germany, 10France Telecom R&D, France, 11Universidad Politecnica de Madrid, Spain www.ist-4more.org

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Cooperative Services for 4G

Abstract— The progress in communication systems has fostered the need for a pragmatic methodology, centered on a user-centric approach, that leads to a novel vision of the Fourth Generation of Mobile Communication Systems (4G) and the definition of its key features and technological development. Along with this view, 4G will be a convergence platform that will provide clear advantages in terms of bandwidth, coverage, power consumption and spectrum usage, thus also offering a variety of new hetero- geneous services (from pop-up advertisements to location-based and interactive or on-demand ones – so called IP datacasting). Though the core is still cellular, the network architecture will be predominantly extended to short-range communication systems, where the users may cooperate in a completely distributed or cellular-controlled fashion. In this paper, we propose new services derived from this vision of 4G and we give an insight of their potential social impact.
Index Terms—4G, Convergence, Cooperation, Heterogeneity, Power consumption, Services, Short-range communication, Spec- trum efficiency, Unlicensed, User-centric, Wireless communica- tion.
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Simone Frattasi1, Bas ̧ak Can1, Frank Fitzek1, Ramjee Prasad1 1Center for TeleInFrastruktur (CTIF), Aalborg University, Niel Jernes Vej 12, 9220, Aalborg, Denmark {sf |bc|f f |prasad}@kom.aau.dk

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The Unpredictable Future: Personal Networks Paving Towards 4G

In this paper we discuss how the network paradigm Personal Networks will become an evolutionary and revolutionary step for communication technology towards the fourth generation communication (4G). For 4G, not only higher data rates, user capacity, latency and data coverage are parameters of interest, but also technology convergence, personalisation and security play leading roles. In this paper we describe and discuss how Personal Network addresses exactly these issues, for which it will pave the technology development towards the envisioned 4G.
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RAMJEE PRASAD AND RASMUS L. OLSEN

Ramjee Prasad is Director of Center for Tele- infrastruktur (CTIF) at Aalborg University, Denmark

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Mapping the Wireless Technology Migration Path: The Evolution to 4G Systems

Wireless service providers around the world are at a business and technological tipping point. Having made investments in legacy technologies that were designed primarily to support voice traffic they now need to cope with new standards, protocols and business imperatives. In so doing, existing business models and technology platforms will be rendered moot. Consider this:
• While the International Telecommunication Union (ITU)-R M.2072 expects voice traffic to account for the lion’s share of volume through 2015, a shift is already underway for revenue to be driven by rich multimedia entertainment services like video messaging or all forms of mobile commerce.
• This shift will place a premium on technologies that maximize bandwidth and throughput while maximizing spectral efficiency,
• Fourth Generation (4G) wireless architectures are rapidly maturing to address these requirements while leveraging the capabilities of Third Generation (3G) technologies, taking advantage of the features associated with an all-IP network system.
As a result of these trends, service providers are scrambling to assess, purchase and deploy new wireless service delivery technologies that will address emerging demand, while maximizing the revenue generated from traditional sources. Those organizations that most effectively manage the transition from Second Generation (2G), 3G and ultimately 4G infrastructures will be best positioned to grow through the rest of the decade and into the next. To that end, this article puts these overlapping wireless standards (2G, 3G and 4G) into a context that will explain the evolution of the wireless technology infrastructure and provide a basis for optimizing a company’s investment in next generation systems and business models.
Public wireless communications have evolved considerably since the emergence of 2G digital wireless cellular technologies in the early ’90s. In their earliest incarnation, Groupe Spécial Mobile (GSM) and its North American counterpart Code division multiple access cdmaOneTM, primarily were designed for voice services (although they did support some limited data capabilities such as Short Message Service [SMS] and low-speed circuit-switched data).
By the late ’90s, 3G cellular systems emerged, driven by the need for a universal and interoperable technology with greater user performances. While 3G technologies offered an improvement on both fronts, incompatibility between different systems remained. From 2003 to 2006, early 3G technologies like Universal Mobile Telecommunications System (UMTS) and cdma2000® offered two key improvements over 2G:
• Simultaneous use of circuit services (like voice and video calls) and packet services (like web browsing or instant messaging)
• Higher speeds (up to 384 kb/s for data in UMTS Release 99 and a peak value of 2.4 Mb/s for the initial release of cdma2000® Evolution Data Optimized (EV-DO)
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By J.-P. Rissen

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4G: A USER-CENTRIC SYSTEM

Abstract—The exponential growth of user demands and the limitations of Third Generation of Mobile Communication Sys- tems (3G) have brought researchers to start reflecting on the Fourth Generation (4G). Many prophetic visions have appeared in literature presenting the future generation as the ultimate boundary of the wireless mobile communication without any limit in its potential, but practically not giving any designing rules and thus any definition of it. In this paper we hence propose a new framework — the user centric system — that, through a satellite hierarchical vision, presents the key features of 4G and points out the various level of interdependency among them. This leads to the identification of the designing rules and therefore to a more pragmatic definition of 4G.
Index Terms— 4G, Heterogeneity, Integration, Personalisation, Reconfigurability, Services, User-centric, Wireless Communica- tion.
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Simone Frattasi1, Hanane Fathi1, Frank Fitzek1, Kiho Chung2, Ramjee Prasad1 1Center for TeleInFrastruktur (CTIF), Aalborg University, Niels Jernes Vej 12, 9220 Aalborg, Denmark {sf |hf |f f |prasad}@kom.aau.dk 2Samsung Electronics, Co., LTD. {khchung}@samsung.com

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4G Features

INTRODUCTION
The approaching 4G (fourth generation) mobile commu- nication systems are projected to solve still-remaining problems of 3G (third generation) systems and to provide a wide variety of new services, from high-quality voice to high-definition video to high-data-rate wireless channels. The term 4G is used broadly to include several types of broadband wireless access communication systems, not only cellular telephone systems. One of the terms used to describe 4G is MAGIC—Mobile multimedia, Anytime any- where, Global mobility support, Integrated wireless solu- tion, and Customized personal service. As a promise for the future, 4G systems, that is, cellular broadband wire- less access systems, have been attracting much interest in the mobile communication arena. The 4G systems not only will support the next generation of mobile service, but also will support the fixed wireless networks.
This paper presents an overall vision of the 4G fea- tures, framework, and integration of mobile communica- tion. The features of 4G systems might be summarized with one word—integration. The 4G systems are about seamlessly integrating terminals, networks, and applica- tions to satisfy increasing user demands.
The continuous expansion of mobile communication and wireless networks shows evidence of exceptional growth in the areas of mobile subscriber, wireless net- work access, mobile services, and applications. An esti- mate of 1 billion users by the end of 2003 justifies the study and research for 4G systems.


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Jawad Ibrahim

jaibrahi@bechtel.com

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A Hybrid Logical Framework

Abstract

The logical framework LF is a constructive type theory of dependent func- tions that can elegantly encode many other logical systems. Prior work has studied the benefits of extending it to the linear logical framework LLF, for the incorporation linear logic features into the type theory affords good representa- tions of state change. We describe and argue for the usefulness of an extension of LF by features inspired by hybrid logic, which has several benefits. For one, it shows how linear logic features can be decomposed into primitive operations manipulating abstract resource labels. More importantly, it makes it possible to realize a metalogical framework capable of reasoning about stateful deduc- tive systems encoded in the style familiar from prior work with LLF, taking advantage of familiar methodologies used for metatheoretic reasoning in LF.

Acknowledgments

From the very first computer science course I took at CMU, Frank Pfenning has been an exceptional teacher and mentor. For his patience, breadth of knowledge, and mathematical good taste I am extremely thankful. No less do I owe to the other two major contributors to my programming languages education, Bob Harper and Karl Crary.

Thanks to all the other students, without which grad school wouldn’t be a tenth as fun. Anything I’ve accomplished here is a footnote to time spent over lunches or at the whiteboards with Kevin, Brigitte, Aleks, Kaustuv, Tom, Donna, Spoons, Deepak, William, Chris, Neel, D, Noam, and Dan. Thanks to all of you!

This work is dedicated to my parents — most surely of all I wouldn’t be where I am today without their support and encouragement.

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User Interactions in Social Networks and their Implications

Abstract

Social networks are popular platforms for interaction, com- munication and collaboration between friends. Researchers have recently proposed an emerging class of applications that leverage relationships from social networks to improve security and performance in applications such as email, web browsing and overlay routing. While these applications of- ten cite social network connectivity statistics to support their designs, researchers in psychology and sociology have re- peatedly cast doubt on the practice of inferring meaningful relationships from social network connections alone. This leads to the question: Are social links valid indicators of real user interaction? If not, then how can we quantify these fac- tors to form a more accurate model for evaluating socially- enhanced applications? In this paper, we address this ques- tion through a detailed study of user interactions in the Facebook social network. We propose the use of interaction graphs to impart meaning to online social links by quanti- fying user interactions. We analyze interaction graphs de- rived from Facebook user traces and show that they exhibit significantly lower levels of the “small-world” properties shown in their social graph counterparts. This means that these graphs have fewer “supernodes” with extremely high degree, and overall network diameter increases significantly as a result. To quantify the impact of our observations, we use both types of graphs to validate two well-known social- based applications (RE [Garriss 2006] and SybilGuard [Yu 2006]). The results reveal new insights into both systems, and confirm our hypothesis that studies of social applica- tions should use real indicators of user interactions in lieu of social graphs.

1. Introduction

Social networks are popular infrastructures for communica- tion, interaction, and information sharing on the Internet. Popular social networks such as MySpace and Facebook provide communication, storage and social applications for hundreds of millions of users. Users join, establish social links to friends, and leverage their social links to share con- tent, organize events, and search for specific users or shared resources. These social networks provide platforms for or- ganizing events, user to user communication, and are among the Internet’s most popular destinations.

Recent work has seen the emergence of a class of socially- enhanced applications that leverage relationships from so- cial networks to improve security and performance of net- work applications, including spam email mitigation [Garriss 2006], Internet search [Mislove 2006], and defense against Sybil attacks [Yu 2006]. In each case, meaningful, interac- tive relationships with friends are critical to improving trust and reliability in the system.

Unfortunately, these applications assume that all online social links denote a uniform level of real-world interper- sonal association, an assumption disproven by social sci- ence. Specifically, social psychologists have long observed the prevalence of low-interaction social relationships such as Milgram’s “Familiar Stranger” [Milgram 1977]. Recent research on social computing shows that users of social net- works often use public display of connections to represent status and identity [Donath 2004], further supporting the hy- pothesis that social links often connect acquaintances with no level of mutual trust or shared interests.

This leads to the question: Are social links valid indi- cators of real user interaction? If not, then what can we use to form a more accurate model for evaluating socially- enhanced applications? In this paper, we address this ques- tion through a detailed study of user interaction events in Facebook, the most popular social network in the US with over 110 million active users. We download more than 10 million user profiles from Facebook, and examine records of user interactions to analyze interaction patterns across large user groups. Our results show that user interactions do in fact deviate significantly from social link patterns, in terms of factors such as time in the network, method of interaction, and types of users involved.

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Equivalence Notions and Model Minimization in Markov Decision Processes

Abstract

Many stochastic planning problems can be represented using Markov Decision Processes (MDPs). A difficulty with using these MDP representations is that the common algorithms for solving them run in time polynomial in the size of the state space, where this size is extremely large for most real-world plan- ning problems of interest. Recent AI research has addressed this problem by representing the MDP in a fac- tored form. Factored MDPs, however, are not amenable to traditional solution methods that call for an ex- plicit enumeration of the state space. One familiar way to solve MDP problems with very large state spaces is to form a reduced (or aggregated) MDP with the same properties as the original MDP by combining “equivalent” states. In this paper, we discuss applying this approach to solving factored MDP problems— we avoid enumerating the state space by describing large blocks of “equivalent” states in factored form, with the block descriptions being inferred directly from the original factored representation. The resulting reduced MDP may have exponentially fewer states than the original factored MDP, and can then be solved using traditional methods. The reduced MDP found depends on the notion of equivalence between states used in the aggregation. The notion of equivalence chosen will be fundamental in designing and analyzing algorithms for reducing MDPs. Optimally, these algorithms will be able to find the smallest possible re- duced MDP for any given input MDP and notion of equivalence (i.e. find the “minimal model” for the in- put MDP). Unfortunately, the classic notion of state equivalence from non-deterministic finite state ma- chines generalized to MDPs does not prove useful. We present here a notion of equivalence that is based upon the notion of bisimulation from the literature on concurrent processes. Our generalization of bisimula- tion to stochastic processes yields a non-trivial notion of state equivalence that guarantees the optimal pol- icy for the reduced model immediately induces a corresponding optimal policy for the original model. With this notion of state equivalence, we design and analyze an algorithm that minimizes arbitrary factored MDPs and compare this method analytically to previous algorithms for solving factored MDPs. We show that previous approaches implicitly derive equivalence relations that we define here.

1 Introduction

Discrete state planning problems can be described semantically by a state- transition graph (or model), where the vertices correspond to the states of the system, and the edges are possible state transitions resulting from actions. These models, while often large, can be efficiently represented, e.g. with factoring, without enumerating the states.

Well-known algorithms have been developed to operate directly on these models, including methods for determining reachability, finding connecting paths, and computing

1optimal policies. Some examples are the algorithms for solving Markov decision proc- esses (MDPs) that are polynomial in the size of the state space [Puterman, 1994]. MDPs provide a formal basis for representing planning problems that involve actions with sto- chastic results [Boutilier et al., 1999]. A planning problem represented as an MDP is given by four objects: (1) a space of possible world states, (2) a space of possible actions that can be performed, (3) a real-valued reward for each action taken in each state, and (4) a transition probability model specifying for each action ˇ and each state p the distri- bution over resulting states for performing action ˇ in state p.

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OPNET Modeler and Ns-2: Comparing the Accuracy Of Network Simulators for Packet-Level Analysis using a Network Testbed

Abstract: - This paper presents a comparative study of two well-known network simulators: OPNET Modeler and Ns- 2. Other studies in this area have generally been confined to just one simulator. The motivation of this paper is to provide a guide to researchers undertaking packet-level network simulations. The simulator outputs were compared to the output from a live network testbed. The experimental comparison consisted of deploying both CBR data traffic, and an FTP session, both on the network testbed and the simulators. CBR data traffic was used due to its simplicity of modeling. A custom analysis tool was employed to examine the behavior of the network in different background traffic scenarios. The same scenarios were then recreated in the simulators in order to ascertain their realism. The results show the necessity of fine-tuning the parameters within a simulator so that it closely tracks the behavior of a real network.

Keywords: network simulator, OPNET Modeler, Ns-2, simulation methodology

1 Introduction

Network simulators have grown in maturity since they first appeared as performance, management and prediction tools. Simulators are normally used as network management tools, for which packet level analysis is not commonly employed. However, more studies are needed to establish guidelines for researchers so that they may select and customise a simulator to suite fine-grained packet level analysis [1][2]. Reference [3] reports `the breach of credibility' that studies based on simulation tools need to tackle; one motivation behind this paper is to address this need. The ease and facility that simulators provide in evaluating “radical” changes to a network environment cannot be discarded. There are a considerable number of simulations tools in the market. The main characteristics that divide them are: accuracy, speed, ease of use, and monetary expense.

This paper concentrates on the accuracy of the simulation in comparison to a real network for packet level analysis. Two of the currently popular network simulators that can perform this type of analysis are Modeler from OPNET1 [4] and Ns-2 from the Virtual Internetwork Testbed project VINT [5]. These are selected because of their popularity within academia, commercial and industrial communities [6].

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Gilberto Flores Lucio, Marcos Paredes-Farrera, Emmanuel Jammeh, Martin Fleury, Martin J. Reed Electronic Systems Engineering Department University of Essex Colchester, Essex C04 3SQ United Kingdom 

gflore@essex.ac.uk, http://privatewww.essex.ac.uk/~gflore/

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Epidemic Routing for Partially-Connected Ad Hoc Networks

Abstract

Mobile ad hoc routing protocols allow nodes with wireless adaptors to communicate with one an- other without any pre-existing network infrastructure. Existing ad hoc routing protocols, while robust to rapidly changing network topology, assume the presence of a connected path from source to destination. Given power limitations, the advent of short-range wireless networks, and the wide physical conditions over which ad hoc networks must be deployed, in some scenarios it is likely that this assumption is invalid. In this work, we develop techniques to deliver messages in the case where there is never a connected path from source to destination or when a network partition exists at the time a message is originated. To this end, we introduce Epidemic Routing, where random pair-wise exchanges of mes- sages among mobile hosts ensure eventual message delivery. The goals of Epidemic Routing are to: i) maximize message delivery rate, ii) minimize message latency, and iii) minimize the total resources consumed in message delivery. Through an implementation in the Monarch simulator, we show that Epidemic Routing achieves eventual delivery of 100% of messages with reasonable aggregate resource consumption in a number of interesting scenarios.

1 Introduction

The advent of inexpensive wireless networking solutions has enabled a broad range of exciting new applica- tions. Wireless network adaptors in portable computing devices, such as cellular phones, personal digital as- sistants, and laptops, can enable ubiquitous access to global information resources. Challenges to achieving this vision include the need to have a wired base station in range of wireless hosts and the energy/expense of transmitting information across large distances. Ad hoc wireless networking addresses some of these challenges by allowing mobile hosts to communicate with one another with no pre-existing communication infrastructure. In ad hoc networks, arbitrary mobile hosts can be recruited to “fill the gap” by serving as in- termediate routers between two hosts that may otherwise not be in direct transmission range of one another. Recent work investigates route discovery and maintenance [6, 16, 19, 21, 25, 26, 27], minimizing power consumption [2, 32], and maintaining QoS guarantees [23, 30, 33] in ad hoc networks.

The common assumption behind existing ad hoc routing techniques is that there is always a connected path from source to destination. However, the advent of short-range wireless communication environments (e.g., Bluetooth [15] and BlueSky [3]) and the wide physical range and circumstances over which such networks are deployed means that this assumption is not always valid in realistic scenarios. Unfortunately, with current ad hoc routing protocols, packets are not delivered if a network partition exists between the source and the destination when a message is originated. Certain applications, such as real-time, constant bit rate communication may require a connected path for meaningful communication. However, a number of other application classes benefit from the eventual and timely delivery of messages, especially in the casewhere frequent and numerous network partitions would prevent messages from ever being delivered end to end. We describe a few of these applications below:

Mobile Sensor Networks: In this example, sensors with wireless connectivity are deployed over a geographic area [11, 17]. These sensors may be simple, e.g., used to detect motion, chemicals, tem- perature, or they may be more sophisticated, e.g., designed to record audio and video. Ideally, these sensors periodically transmit their findings to a base station, perhaps for analysis or permanent stor- age. These sensors may be small and have limited communication range, implying that they are not always able to establish a connected path (leveraging other sensors as routers) back to base stations. Such sensors may be mobile — for example, under their own power1 or because they are suspended in air/water — implying that individual sensors may periodically come into contact with one another through node mobility.

Smart Dust: Related to the previous example, a recent proposal [20] describes challenges in net- works comprised of Micro-electrical Mechanical Sensors (MEMS). Because of the power restrictions associated with their small size, these sensors might utilize optical connections for communication, requiring line of sight between each hop in a connected optical path from source to destination. Fre- quent physical obstructions may make the presence of such a “connected” line of sight path unlikely in some cases, though eventual pair-wise connectivity among MEMS is more likely if the MEMS are mobile.

Disaster Recovery/Military Deployment: In this example, people, in addition to sensors, are deployed over an area with limited wireless coverage (i.e., few, if any, base stations). For disaster recovery, field agents wish to communicate their findings regarding, for example, environmental hazards or survivors to other field agents as well as to a command post. Again, battery concerns and the wide physical dispersement of individual agents make it unlikely that full wireless connectivity can be continuously maintained among all mobile hosts.

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Amin Vahdat and David Becker Department of Computer Science Duke University Durham, NC 27708 (vahdat,becker)@cs.duke.edu

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Using Cognitive Architectures to Improve Robot Control: Integrating Production Systems, Semantic Networks, and Sub-Symbolic Processing

ABSTRACT: In the last several years, a collection of systems have been designed around cognitive psychological principles in an attempt to reproduce the thought patterns of the human mind. These cognitive architectures have made progress in modeling human thought through production system architectures; however, they traditionally have little interaction with the outside world. Additionally, these systems place a heavy burden on the modeler to hand code large memory structures. In this paper, we explore the architecture and capabilities of the Symbolic and Sub-symbolic Robotic Intelligence Control System (SS-RICS) which was inspired by cognitive architectures capable of higher order cognition such as the Adaptive Control of Thought-Rational. SS-RICS integrates production systems, semantic networks, machine learning and sub-symbolic processing to perform real-time mobile robot control. It is our belief that this integration of cognitive psychological techniques and AI techniques will allow mobile robots to have higher order understanding and interaction with the dynamic world in which we live.

Keywords: Cognitive Architectures, Mobile Robots, Semantic Networks, Production Systems, Hybrid Systems

1. Introduction

In the last several years, a collection of systems have been designed around cognitive psychological principles in an attempt to reproduce the thought patterns of the human mind. Such systems include the Adaptive Control of Thought Rational (ACT-R) (Anderson and Lebiere, 1998) and Soar (Newell, 1990). The primary goal of these systems is to model human mental processes, human knowledge, the nature of that knowledge, and how the knowledge is utilized and acquired. Soar and ACT-R have been designed on similar grounds in an attempt to define a unified theory of cognition and merge a number of cognitive phenomena into a single architecture (Newell, 1990). The semantic network Cyc fits into a more general category of knowledge representation systems in that its primary goal is to acquire a vast knowledge base spanning human consensus knowledge to build “programs with common sense” (Lenat, 1990). SS- RICS falls somewhere in the middle of these systems, as it is an attempt to merge large knowledge acquisition systems with cognitive psychological principles while utilizing traditional artificial intelligence (AI) techniques.

The AI community has struggled with the question of

how to reproduce the thought patterns of the human mind for years, resulting in two distinct paradigms (Sun, 2000). The first camp takes a psychological approach utilizing symbolic representations to drive intelligent systems and the second focuses on a mathematical approach utilizing distributed representations constructed with structures such as neural or connected networks. This clash was summarized particularly well by Minsky in an MIT-AI Laboratory Memo written in the early seventies.

“Workers from psychology inherit stronger desires to minimize the variety of assumed mechanisms. I believe this leads to attempts to extract more performance from fewer "basic mechanisms" than is reasonable. Such theories especially neglect mechanisms of procedure control and explicit representations of processes. On the other side, workers in Artificial Intelligence have perhaps focused too sharply on just such questions. Neither have they given enough attention to the structure of knowledge, especially procedural knowledge.” (Minsky 1974)

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*Eric Avery, Troy Kelley, *Dr. Darush Davani

*Department of Computer and Information Sciences Towson State University, Towson, MD 21204 

eavery1@towson.edu, ddavani@ towson.edu

US Army Research Laboratory Human Research and Engineering Directorate Aberdeen Proving Ground, 

Aberdeen, MD 21005 tkelley@arl.army.mil

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