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In this article the author cites the five papers presented in the "Institute of Electrical and Electronics Engineers (IEEE) First International Conference on Biometrics: Theory, Applications, and Systems," or BTAS 07, held in Washington, D.C. on September 27-29, 2009. It states that the papers received positive reviews and were revised for the special section of "IEEE Transactions on Systems, Man, and Cybernetics-Part A." Among these papers were authored by Elaine Newton and P. Jonathan Phillips, and Andreas Humm and colleagues from the University of Fribourg in Switzerland.

Editorial. Comments on the research directions in information technology. Possibility of global connectivity through information; Provision of access to data and communication through computer networks commonly called as cybernetics; Problems associated with information assurance.

Studies buffer management in real-time active database systems. Issues involved in real-time database systems; Executive model for active real-time transactions; Buffer allocation and placement in PAPER, a buffer management scheme; Anticipatory prefetching.

Nonverbal vocal interaction (NVVI) is an input modality by means of which users control the computer by producing sounds other than speech. Previous research in this field has focused mainly on studying isolated instances of NVVI (such as mouse cursor control in computer games) and their performance. This paper presents a study with 36 elderly users in which basic NVVI vocal gestures (commands) were ranked by their perceived fatigue, satisfaction, and efficiency. The results of this study inspired a set of NVVI gesture design guidelines that are also presented in this paper. [ABSTRACT FROM PUBLISHER]

The eight papers in this special section focus on health-care management and optimization, the use of advanced networking and information technologies in health care services, and the provision of high-quality health care to improve medical services. [ABSTRACT FROM PUBLISHER]

In group decision making, consensus models are decision aid tools and help experts modify their individual opinions to reach a closer agreement. Based on the concept of minimum-cost consensus, this paper proposes a novel framework to achieve minimum-cost consensus under aggregation operators. Analytical results indicate that the proposed framework reduces to the consensus model of Ben-Arieh when the selected aggregation operator is the ordered weighted averaging (OWA) operator with weight vector (1/2, \ldots, 0, \ldots, 1/2)^T. Furthermore, this paper closely examines the minimum-cost consensus models with a linear cost function under the common aggregation operators (e.g., the weighted averaging operator and the OWA operator). Linear-programming-based approaches are also developed to solve these models. The results of this paper significantly contribute to efforts to develop the consensus model of Ben-Arieh [ABSTRACT FROM PUBLISHER]

This paper introduces a methodology to extend the capabilities of the dynamic inoperability input-output model (DIIM) to account for perturbations to sectors of the economy that are time varying and probabilistic. The DILM accounts for the interdependent nature of the economy in determining the impact of a disruption on the ability of each economic sector to satisfy the prevailing demand. While the original formulation of the DIIM only allows for a single perturbation vector, this paper extends the DIIM to allow a perturbation matrix to be utilized as inputs to the model. The underlying motivation for this paper is understanding the impact of a pandemic on a regional economy. As such, idiosyncrasies associated with a pandemic are also accounted for in the model formulation. These include translating workforce absenteeism into a measure of sector inoperability and accounting for the impact of long-term absenteeism on a sector's ability to deliver its as-planned production output. [ABSTRACT FROM AUTHOR]

Software-quality data sets tend to fall victim to the class-imbalance problem that plagues so many other application domains. The majority of faults in a software system, particularly high-assurance systems, usually lie in a very small percentage of the software modules. This imbalance between the number of fault-prone (fp) and non-fp (nfp) modules can have a severely negative impact on a data-mining technique's ability to differentiate between the two. This paper addresses the classimbalance problem as it pertains to the domain of software-quality prediction. We present a comprehensive empirical study examining two different methodologies, data sampling and boosting, for improving the performance of decision-tree models designed to identify fp software modules. This paper applies five data-sampling techniques and boosting to 15 software-quality data sets of different sizes and levels of imbalance. Nearly 50000 models were built for the experiments contained in this paper. Our results show that while data-sampling techniques are very effective in improving the performance of such models, boosting almost always outperforms even the best data-sampling techniques. This significant result, which, to our knowledge, has not been previously reported, has important consequences for practitioners developing software-quality classification models. [ABSTRACT FROM AUTHOR]

Conventional humanoid robotic behaviors are directly programmed depending on the programmer's personal experience. With this method, the behaviors usually appear unnatural. It is believed that a humanoid robot can acquire new adaptive behaviors from a human, if the robot has the criteria underlying such behaviors. The aim of this paper is to establish a method of acquiring human behavioral criteria. The advantage of acquiring behavioral criteria is that the humanoid robots can then autonomously produce behaviors for similar tasks with the same behavioral criteria but without transforming data obtained from morphologically different humans every time for every task. In this paper, a manipulator robot learns a model behavior, and another robot is created to perform the model behavior instead of being performed by a person. The model robot is presented some behavioral criteria, but the learning manipulator robot does not know them and tries to infer them. In addition, because of the difference between human and robot bodies, the body sizes of the learning robot and the model robot are also made different. The method of obtaining behavioral criteria is realized by comparing the efficiencies with which the learning robot learns the model behaviors. Results from the simulation have demonstrated that the proposed method is effective for obtaining behavioral criteria. The proposed method, the details regarding the simulation, and the results are presented in this paper. [ABSTRACT FROM AUTHOR]

Several continuous manufacturing processes use stochastic texture images for quality control and monitoring. Large amounts of pictorial data are acquired, providing important information about both the materials produced and the manufacturing processes involved. However, it is often difficult to measure objectively the similarity among industrial stochastic images or to discriminate between texture images of stochastic materials with distinct properties. Nowadays, the degree of discrimination required by industrial processes often goes beyond the limits of human visual perception. This paper proposes to model this specific class of textures as colored noise and presents a new approach for multiresolution stochastic texture representation and discrimination in industry (e.g., nonwoven textiles and paper). The wavelet transform is used to represent stochastic texture images in multiple resolutions and to describe them using local orientation and density variability as features. Based on this representation, a multiresolution distance measure for stochastic textures is proposed, and industrial applications of the method and experimental results are reported. The conclusions include ideas for future work. [ABSTRACT FROM AUTHOR]

Although there has been a pickup in the growth of business-to-consumer electronic commerce (EC) recently, the overall growth appears to have failed to live up to the various forecasts. Notwithstanding the concerns of security and privacy, this paper posits that for complex products and services offered on the web, existing EC interfaces (ECIs) lack the necessary "richness' to overcome the virtual nature that consumers face compared with a physical store. We empirically validate a conceptual framework that exists in the literature to address these issues of ECI design by drawing on insights from contingency research in information system (IS) design arid media choice behavior. This paper finds that a fit or congruence between the product type and the ECI richness (in product information representation, and product-related interaction and communication between the consumer and. vendor) leads to superior outcomes. Specifically, buying a complex product (e.g., digital camera) on the Web requires a greater ECI richness in the form of experiencing higher social presence and/or higher product presence. On the other hand, a lean ECI is sufficient for a simple product (e.g., diskette). The role of tolerance for ambiguity (TA), which is an individual difference variable, in this relationship is also examined. A significant three- way fit of TA with ECI richness and product types on consumer behavior is found. A number of implications and future research extensions are discussed. [ABSTRACT FROM AUTHOR]

The article focuses on deadlocks in operating systems. Deadlocks constitute an important issue in the design and operation of various computer-integrated systems. These systems range from automated production system and transportation system to computer operating systems, concurrent software systems, computer networks and distributed database systems. Many of these systems include human in a loop. A deadlock arises when two or more processes in the system, each holding some resources, request the resources occupied by one another such that a circular wait is formed. In the presence of deadlocks, the system loses its partial or total operational functionality and may increase its operational cost.

This paper addresses the problem of optimizing logistic processes that can be modeled as a birth-and-death process. A fuzzy decision making algorithm is proposed to assign components to orders, which is a common task in a large number of logistic processes. The dynamic assignment of components to orders is the key issue in optimizing logistic processes. This paper proposes several criteria for this optimization. These criteria are combined using weighted fuzzy aggregation in a fuzzy decision making environment. First, a simple but illustrative example shows that the proposed techniques can be applied with good results to this type of processes. Then, the proposed method is applied to a real-world logistic process at Fujitsu-Siemens Computers. [ABSTRACT FROM AUTHOR]

The article discusses various papers published within the issue including one by Jia Shen and colleagues on collaborative online examinations and another one by John R. Voit and Colin G. Drury on vicarious learning with collaborative lessons learned programs.

There is increasing need for agencies to coordinate their interdependent risk assessment, risk management, and risk communication activities in compliance with risk program guidelines. In particular, there is a challenge to measure risk program compliance and maturity to guidelines such as the U.S. Office of Management and Budget (OMB) memorandum “Updated Principles for Risk Analysis” among others. This paper demonstrates a systemic approach to evaluate large-scale risk program maturity with utilization of business process modeling and self-assessment methods. This approach will be helpful to agencies implementing risk guidelines such as those of the OMB, the U.S. Government Accountability Office, the U.S. Department of Homeland Security, the U.S. Department of Defense, and others. This paper will be of interest to risk managers, agencies, and risk and safety analysts engaged in the conception, implementation, and evaluation of risk and safety programs. [ABSTRACT FROM PUBLISHER]

This paper presents a novel concept of modeling biological systems by means of preserving the natural rules governing the system's dynamics, i.e., their intrinsic fractal (recurrent) structure. The purpose of this paper is to illustrate the capability of recurrent ladder networks to capture the intrinsic recurrent anatomy of neural networks and to provide a dynamic model which shows typical neuronal phenomena, such as the phase constancy. As an illustrating example, the simplified model for a neural network consisting of motor neurons is used in simulation of a recurrent ladder network. Starting from a generalized approach, it is shown that, in the steady state, the result converges to a constant-phase behavior. The outcome of this paper indicates that the proposed model is a suitable tool for specific neural models in various neuroscience applications, being able to capture their fractal structure and the corresponding fractal dynamic behavior. A link to the dynamics of EEG activity is suggested. By studying specific neural populations by means of the ladder network model presented in this paper, one might be able to understand the changes observed in the EEG with normal aging or with neurodegenerative disorders. [ABSTRACT FROM PUBLISHER]

An ensemble empirical mode decomposition (EEMD)-based approach was developed to extract steady-state visual evoked potentials (SSVEPs) for wireless handling of a small robot car. Three visual stimuli, flickering at 13, 14, and 15 Hz, were displayed on a liquid crystal display monitor to induce user's SSVEPs. The induced SSVEPs were used to control three movement functions (forward, left, and right) of the small robot car. Users gazed at one chosen visual stimulus at one time, and the induced SSVEP was recognized to activate the desired movement function. In this paper, all subjects were requested to handle the small robot car to complete an S-shaped course four times. The proposed system utilized only one electroencephalography (EEG) channel placed at the Oz position. The acquired EEG signals were first segmented into 1-s epochs, and each epoch was then decomposed by EEMD into a series of oscillation components, denoted as intrinsic oscillatory functions (IOFs), representing multiscale features of the recorded signal. The SSVEP-related IOFs were then recognized using a matched filter detector (MFD), including a matched filter demodulator and an amplitude detector. The visual stimulus, which contributed maximum power to the MFD, was recognized as the gazed target. In this paper, all subjects could actuate the small robot car using the proposed EEMD-based brain computer interface system to complete an S-shaped course four times; the mean execution time, number of valid detections, and command transfer interval over the 11 subjects were 84.5 s, 51.13 commands, and 1.65 s/command, respectively. [ABSTRACT FROM PUBLISHER]

The end-of-life (EOL) disassembly sequencing problem (DSP) has become increasingly important in the process of handling EOL products. This paper proposes a solution procedure for the “EOL DSP”; the procedure is based on a novel soft-computing algorithm that utilizes modified “simplified swarm optimization,” and the procedure combines the precedence preservative operator, feasible solution generator, self-adaptive parameter control, and repetitive pairwise exchange procedures. By taking into consideration the non-deterministic polynomial time (NP)-complete nature of the problem, the proposed algorithm efficiently seeks the optimal disassembly sequence with a novel approach; this approach involves reducing the initial solution space and using a combination of soft-computing algorithms for achieving higher computational efficiency and solution quality. The results presented in this paper show that the proposed algorithm outperforms the existing algorithms in terms of solution quality achieved in a limited computation time. [ABSTRACT FROM PUBLISHER]

In new widespread peer-to-peer (P2P) systems, peers are exposed to great risk due to frequent trading with unfamiliar peers. Therefore, trust and reputation mechanisms become important issues. For computational efficiency, this paper focuses on localized information trust/reputation mechanisms. Previous studies have not paid much attention to the overall distribution of peer interactions. Based on the scale-free feature of real-world networks, we introduce a power-law distribution of the number of neighbors in P2P trust and reputation systems. To rigorously distinguish the effects of the overall considerations introduced herein, we compare the model proposed in this paper with models in previous studies under the same set of parameters. Simulation results show that the proposed model can discern a small difference between real quality of service (QoS) and other peers' feedback while distinguishing the malicious peers, even when the exaggeration coefficient is high. When one or a group of peers change their QoS, the model exhibits a quick reaction to this change. This response is demonstrated by a rapid decrease in reliability when the QoS change is downward and a slow increase when the change is upward. A slow reaction to the upward QoS change may exclude those peers who frequently change their QoS and encourage consistent reliable service providers. [ABSTRACT FROM PUBLISHER]

Text summarization techniques have been found to be effective with regard to helping users find relevant information faster. The effectiveness and efficiency of a user's performance in an information-seeking task can greatly be improved if he/she needs to only look at a summary that includes the relevant information presented in his/her preferred manner. On the other hand, if the main idea is misrepresented and/or omitted altogether from a summary, it may take users more time to solve a target problem or, even worse, lead users to make incorrect decisions. There is an important need to design a personalized text summarization system that takes into account both what a user is currently interested in and how a user perceives information. The latter factor is referred to as a user's cognitive styles. Although there are some existing approaches that have employed a user's interests to help in the design of a personalized text summarization system, there has been inadequate focus on exploring cognitive styles. This paper aims at studying the impact of a user's cognitive styles when assessing multidocument summaries. In particular, we choose two dimensions of a user's cognitive style—the analytic/wholist and verbal/imagery dimensions—and study their impacts on how a user assesses a summary that was generated from a set of documents. In particular, the type of a document set refers to whether the set's content is loosely or closely related. We use a document set type to explore if there are any differences in the users' assessments of summaries that were generated from sets of different types. The results of this paper show that different users have different assessments with regard to information coverage and the way that information is presented in both loosely and closely related document sets. In addition, we found that the coherency ratings that were given to summaries from the two types of document sets were significantly different between the analytic and wholist groups. This result leads us to investigate the impact of a user's cognitive styles and the following two factors that directly relate to the coherence of a summary: 1) graph entropy and 2) the percentage of stand-alone concepts. We found that these two factors and a user's cognitive styles affect a user's ratings on the coherency of a summary. [ABSTRACT FROM PUBLISHER]

In the context of the Next Generation Air Transportation System and Single European Sky ATM Research future airspace programs, this paper describes a concept for an airborne separation assurance display that is designed to aid pilots in their task of self-separation, by visualizing the possibilities for conflict resolution that the airspace provides. This paper is part of an ongoing research toward an ecological design of a separation assistance interface that can present all the relevant properties of the spatiotemporal separation problem. A work-domain analysis is described from which several perspective projections of traffic properties and travel constraints are derived. A display concept is proposed that presents heading and altitude action possibilities in a flight-path angle–track angle action space. Key issues in the current design are discussed, with recommendations for future work. [ABSTRACT FROM PUBLISHER]

Distributed virtual machines can help to build scalable, manageable, and efficient grid infrastructures. The work proposed in this paper focuses on employing virtual machines for grid computing. In order to efficiently run grid applications, virtual machine resource information should be provided. This paper first discusses the system architecture of virtual machine pools and the process of information retrieval from virtual machines. Based on the characterization of the system model, this paper presents the work on how to retrieve resource information from Xen/VMware virtual machines via VMware Common Information Model Software Development Kit and lightweight Java agents. The resource information is integrated into a grid information service. The work is implemented in a test bed with Xen/VMware virtual machines and the Globus Toolkit. With a performance evaluation and discussion on a real test bed, it is declared that the design and implementation of information services for virtual-machine-based grid systems are feasible, efficient, and scalable. [ABSTRACT FROM PUBLISHER]

Large organizations usually have difficulties in dealing with the exponential growth of information. Therefore, there is a high demand for innovative solutions to deal with such growth and to integrate such information. This paper proposes a new approach, called Emergent Ontologies (EOs), toward the generation of a single organizational ontology through which it becomes possible to browse all information of an organization. This proposal considers that, typically, an organization's information is distributed in peers, and that in each peer, this information could be represented through a different ontology. As each peer of an organization needs to exchange information, peer-to-peer mappings are created to bridge these ontologies. Based on these mappings, this paper proposes a set of heuristics, which are used to generate the EO. These heuristics have been incorporated into the OntoEmerge system, a prototype developed to facilitate the creation of an initial organization ontology. In order to evaluate such a system and the heuristics behind it, some experiments have been performed. A quantitative and qualitative analysis of these experiments is also presented in this paper. This approach presents encouraging results, and this fact can be considered as a starting point for the creation of organizational ontologies. [ABSTRACT FROM AUTHOR]

This paper addresses R&D portfolio selection in social institutions, state-owned enterprises, and other nonprofit organizations which periodically launch a call for proposals and distribute funds among accepted projects. A nonlinear discontinuous bicriterion optimization model is developed in order to find a compromise between a portfolio quality measure and the number of projects selected for funding. This model is then transformed into a linear mixed-integer formulation to present the Pareto front. Numerical experiments with up to 25 000 projects competing for funding demonstrate a high computational efficiency of the proposed approach. The acceptance/rejection rules are obtained for a portfolio using the rough set methodology. [ABSTRACT FROM AUTHOR]

A pandemic outbreak is one of the major planning scenarios considered by emergency-preparedness policymakers. The consequences of a pandemic can significantly affect and disrupt a large spectrum of workforce sectors in today's society. This paper, motivated by the impact of a pandemic, extends the formulation of the dynamic inoperability input—output model (DIIM) to account for economic perturbations resulting from such an event, which creates a time-varying and probabilistic inoperability to the workforce. A pandemic is a unique disaster, because the majority of its direct impacts are workforce related and it does not create significant direct impact to infrastructure. In light of this factor, this paper first develops amethod of translating unavailable workforce into a measure of economic-sector inoperability. While previous formulations of the DIIM only allowed for the specification of an initial perturbation, this paper incorporates the fact that a pandemic can cause direct effects to the workforce over the recovery period. Given the uncertainty associated with the impact of a pandemic, this paper develops a simulation framework to account for the possible variations in realizations of the pandemic. The enhancements to the DIIM formulation are incorporated into a MatLab program and then applied to a case study to simulate a pandemic scenario in the Commonwealth of Virginia. [ABSTRACT FROM AUTHOR]

Class imbalance is a problem that is common to many application domains. When examples of one class in a training data set vastly outnumber examples of the other class(es), traditional data mining algorithms tend to create suboptimal classification models. Several techniques have been used to alleviate the problem of class imbalance, including data sampling and boosting. In this paper, we present a new hybrid sampling/boosting algorithm, called RUSBoost, for learning from skewed training data. This algorithm provides a simpler and faster alternative to SMOTEBoost, which is another algorithm that combines boosting and data sampling. This paper evaluates the performances of RUSBoost and SMOTEBoost, as well as their individual components (random undersampling, synthetic minority oversampling technique, and AdaBoost). We conduct experiments using 15 data sets from various application domains, four base learners, and four evaluation metrics. RUSBoost and SMOTEBoost both outperform the other procedures, and RUSBoost performs comparably to (and often better than) SMOTEBoost while being a simpler and faster technique. Given these experimental results, we highly recommend RUSBoost as an attractive alternative for improving the classification performance of learners built using imbalanced data. [ABSTRACT FROM AUTHOR]

This correspondence paper presents the validation of a formation-flight control technique with obstacle avoidance capability based on nonlinear model predictive algorithms. Control architectures for multiagent systems employed in this correspondence paper can be categorized as centralized, sequential-decentralized, and fully decentralized methods. Centralized methods generally have better performance than decentralized methods. However, it is well known that the performance of the centralized methods for formation flight degrades when there exists communication failure among the vehicles, and they require more computation time than the decentralized method. This correspondence paper evaluates the control performance and the computation time reduction of the sequential-decentralized and fully decentralized methods in comparison with the centralized method and shows that the fully decentralized method can be made effective against short-term communication failure. The control inputs for formation flight are computed by nonlinear model predictive control (NMPC). The control input saturation and state constraints are incorporated as inequality constraints using Karush-Kuhn-Tucker conditions in the NMPC framework, and the collision avoidance can be considered in real time. The proposed schemes are validated by numerical simulations, which include the process and measurement noise for more realistic situations. [ABSTRACT FROM AUTHOR]

The human arm exhibits outstanding manipulability in executing various tasks by taking advantage of its intrinsic compliance, force sensation, and tactile contact clues. By examining human strategy in controlling arm impedance, we may be able to understand underlying human motor control and develop control methods for dexterous robotic manipulation. This paper presents a novel method for estimating multijoint stiffness by using electromyogram (EMG) and an artificial neural network model. The artificial network model developed in this paper relates EMG data and joint motion data to joint stiffness. With the proposed method, the multijoint stiffness of the arm was estimated without complex calculation or specialized apparatus. The feasibility of the proposed method was confirmed through experimental and simulation results. [ABSTRACT FROM AUTHOR]

Group consensus is an important method for making business decisions. In this paper, the consensus process is defined as a dynamic and interactive group decision process, which is coordinated by a moderator who helps the experts to gradually move their opinions closer to each other. This paper describes the importance of group consensus and the need to minimize the cost of this process. Furthermore, this paper describes the costs associated with decision making using group consensus and then describes three methods of reaching consensus assuming quadratic costs for a single-criterion decision problem. The first method finds the group opinion (consensus) that yields the minimum cost of reaching throughout the group. The second method finds the opinion with the minimum cost of the consensus provided that all experts must be within a given distance of the group opinion. The last method finds the maximum number of experts that can fit within the consensus, given a specified budget constraint. [ABSTRACT FROM AUTHOR]

Data warehousing (DW) has emerged as one of the most powerful technology innovations in recent years to support organization-wide decision making and has become a key component in the information technology (IT) infrastructure. Proponents of DW claim that its infusion can dramatically enhance the ability of businesses to improve the access, distribution, and sharing of information and provide managerial decision support for complex business questions. DW is also an enabling technology for data mining, customer-relationship management, and other business-intelligence applications. Although data warehouses have been around for quite some time, they have been plagued by high failure rates and limited spread or use. Drawing upon past research on the adoption and diffusion of innovations and on the implementation of information systems (IS), we examine the key organizational and innovation factors that influence the infusion (diffusion) of DW within organizations and also examine if more extensive infusion leads to improved organizational outcomes. In this paper, we conducted a field study, where two senior managers (one from IS and the other from a line function) from 117 companies participated, and developed a structural model to test the research hypotheses. The results indicate that four of the seven variables examined in this paper—organizational support, quality of the project management process, compatibility, and complexity—significantly influence the degree of infusion of DW and that the infusion, in turn, significantly influences organization-level benefits and stakeholder satisfaction. The findings of this paper have interesting implications for both research and practice in IT and DW infusion, as well as in the organization-level impact of the infusion of enterprise-wide infrastructural and decision support technologies such as DW. [ABSTRACT FROM AUTHOR]

Over the past few years, automatic target recognition (ATR) has emerged as an essential image analysis tool to identify objects from temporally and spatially disjoint possibly noisy image data. For many current applications, ATR is performed by unmanned aerial vehicles (UAVs) that fly within a reconnaissance area to collect image data through sensors and upload the data to a central ground control station for analyzing and identifying potential targets. The centralized approach to ATR introduces several problems, including scalability with the number of UAVs, network delays in communicating with the central location, and the susceptibility of the system to malicious attacks on the central location. These challenges can be addressed by using a distributed system for performing ATR. In this paper, we describe a multiagent-based prototype system that uses swarming techniques inspired from insect colonies to perform ATR using UAVs in a distributed manner within simulated scenarios. We assume that UAVs are constrained in the resources available onboard and in their capabilities for performing ATR due to payload limitations. Our focus in this paper is on the coordination aspects between UAVs to efficiently decide how they are to act by using a swarming mechanism. We describe algorithms for the different operations performed by the UAVs in the system and for different swarming strategies, which are embedded within software agents located on the UAVs. We provide empirical simulations of our system within a simulated area of interest to determine its behavior in different scenarios with varying operational constraints. Our experimental results indicate that swarming strategies for distributed ATR perform favorably compared with centralized ATR strategies. [ABSTRACT FROM AUTHOR]

This paper proposes an approach for providing tolerance against faults that may compromise the functionality of a given controller modeled by a Petri net. The method is based on embedding the given Petri net controller into a larger (redundant) Petri net controller that retains the original functionality and properties, and uses additional places, connections, and tokens to impose invariant conditions that allow the systematic detection and identification of faults via linear parity checks. In particular, this paper considers two types of redundant Petri net controllers: 1) nonseparate redundant Petri net controllers have the same functionality as the given Petri net controller and allow for fault detection and identification, but do not necessarily retain the given controller intact; and 2) separate redundant Petri net controllers are a special case of the nonseparate redundant controllers that retain the given Petri net controller intact but enhance it with additional places to enable fault detection and identification. The work in this paper obtains complete characterizations of both types of redundant controllers along with necessary and sufficient conditions for them to be bisimulation equivalent to the given original Petri net controller. In addition, this paper discusses how each type of redundant controllers can be designed to have desirable fault detection and identification capabilities. When the bisimulation equivalence requirement is not directly enforced, nonseparate redundant controllers can potentially have advan- tages over separate ones (e.g., they can use fewer connections to detect and identify the same number of faults). An example of a Petri net controller for a production cell and its fault tolerance capabilities using separate and nonseparate embeddings is used to illustrate the approach. [ABSTRACT FROM AUTHOR]

Flexibility of flexible manufacturing systems (FMSs) has been considered as an effective tool to compete in the present manufacturing environment. Enormous research efforts have been made to harness the benefits of flexibility through superior control strategies. While modeling flexibility and control strategies, researchers have mostly assumed an information system that can provide real-time control. Literature qualitatively reports that the real-time control can be highly capital intensive and difficult to achieve. This paper focuses on FMS operating under review-period (RP)-based control and presents a combined study of routing flexibility (RF), control strategies, and information system under Taguchi's method using simulation. RP-based control for FMS has been compared with real-time control. This paper contributes an approach for the decision maker to study the performance of an FMS operating under RP control and to identify the periodicity (time interval) of RP that will not deteriorate its performance in comparison to real-time control. It also helps the decision maker to reach a tradeoff between RP-based control and real-time control. The results show that RP-based control can be effectively implemented on an FMS having lower RF level. RP-based control can outperform real-time control with a superior control strategy and smaller RP size. The results under Taguchi's method suggest that the RF and control strategy should have maximum relative percentage contributions in FMS performance, whereas contribution of the RP (information system) should be minimum. Increasing the relative percentage contribution of the information system may deteriorate the performance of FMS. The information system is needed as a catalyst to facilitate the the contributions of other factors in improving the FMS performance and not its own contribution. [ABSTRACT FROM AUTHOR]

Online advertising continues to be a significant source of income for many Internet-based organizations. Recent indications of improved economic growth are having an impact on advertisement revenue, with the estimated online advertising revenue in the United States for the fourth quarter of 2003 totaling a record of $2.2 billion. A substantial portion of this income comes from banner advertisements, and efficient scheduling of these advertisements could result in a considerable increase in profits. The problem of scheduling banner advertisements has been observed to be intractable via traditional optimization techniques and has received only limited attention in the literature. In addition, all past attempts to address this problem have been based on an ‘all-or-nothing’ framework, where a customer specifies the exact number of copies of the ad to be displayed over the planning horizon, if it is selected for display by the provider of the advertisement space. This paper extends it to a more realistic setting, where the customer is allowed to specify a set of acceptable display frequencies. The Lagrangian decomposition-based solution approaches presented in this paper are observed to provide good schedules in a reasonable period of time. [ABSTRACT FROM AUTHOR]

The anthropomorphic biped robot Bip is equipped with sensors for measuring the ground/feet forces in order to localize the center of pressure (CoP) and zero moment point (ZMP). This paper focuses on experimental results regarding the evolution of the ground contact forces, obtained from a human walker wearing the robot feet as shoes. First, one determines the influence of heavy and rigid metallic shoes on the gait of the subject, during experiments carried out on flat ground. Second, the evolution of the contact forces is studied while walking on parallel planes with different elevations (stairs), then one addresses the case where the feet are supported by two nonparallel planes (uneven terrain). The corresponding analysis is founded on the concepts of virtual supporting surface and pseudo-CoP-ZMP introduced in a companion paper, discussing the theoretical aspects of CoP and ZMP (Sardain and Bessonnet, 2004). Beyond the academic contribution, the dab analyzed in this paper could constitute an incitement to design truly anthropomorphic feet, for Bip as well as for other biped robots, because all the current robot feet are functionally rather poor. [ABSTRACT FROM AUTHOR]

A currency crisis is an economic event where a country's fixed exchange rate is under pressure by speculators. In some cases, currency crises are followed by strong recessions (e.g., recent Asian and Argentinean crises), but in other cases they are not. This paper seeks to determine what are the most significant factors in explaining the consequences of currency crises on the economy. This paper collects data on 25 variables for 64 currency crises between 1970 and 1999. This research uses a novel algorithm with support vector machines (SVM) for selecting significant variables. This algorithm works well with datasets characterized by nonlinearity and low variable-observation ratio. Variables of banking size and fragility, international trade, and devaluation were the most significant. Variables of banking supervision, economic development, and IMF intervention were found less significant. The variable selection results of the algorithm were compared with all-best subsets variable selection. The results of our algorithm are more consistent with the economic literature than the results from all-best subsets. [ABSTRACT FROM AUTHOR]

A variety of important Petri net-based methods to prevent deadlocks arising in flexible manufacturing systems (FMS) are to add some control places and related arcs to strict minimal siphons (SMS) such that no siphon can be emptied. Since the number of minimal siphons grows in general exponentially with respect to a Petri net size, their disadvantages lie in that they often add too many additional places to the net, thereby making the resulting net model much more complex than the original one. This paper explores ways to minimize the new additions of places while achieving the same control purpose. It proposes for the first time the concept of elementary siphons that are a special class of siphons. The set of elementary siphons in a Petri net is generally a proper subset of the set of all SMS. Its smaller cardinality becomes evident in large Petri net models. This paper proves that by adding a control place for each elementary siphon to make sure that it is marked, deadlock can be successfully prevented. Compared with the existing methods, the new method requires a much smaller number of control places and, therefore, is suitable for large-scale Petri nets. An FMS example is used to illustrate the proposed concepts and policy, and show the significant advantage over the previous methods. [ABSTRACT FROM AUTHOR]

The paper deals with a multiple attribute decision making methodology when a decision maker (DM) specifies her/his preferences in imprecise ways, which is basically an extended version of Malakooti's prior work. Usually, it is said that the DM is willing, or able, to provide partial information, because of time pressure, lack of domain knowledge, or data and the like. In this paper, we consider two categories of partial preference information. First, partial information is related to holistic preference judgments about some pair of alternatives. Second, in a situation where the characteristics of some attributes considered are abstract, or non-commensurate, it is sometimes difficult to make an exact performance evaluation of alternatives with respect to those attributes. To circumvent this difficulty, we allow the DM to specify partial information on performance evaluations, which is similar to the types of preference judgments on some pairs of alternatives. Prioritizing multiple attribute alternatives under two categories of partial information causes an intractable nonlinear program, which is the first issue we try to resolve in the paper. We further propose a measure of preference strength as a decision rule. With partial information, often the use of strict dominance rule yields a larger number of non-dominated candidates than the DM wants. Assume a situation where the DM is not willing to provide additional information to reduce the number of non-dominated candidates, but she/he wants to have a single optimal candidate or rank ordering of alternatives. It is then necessary to develop a method like one we propose as a preference strength measure. [ABSTRACT FROM AUTHOR]

Assessment of reliability and safety of a complex system with sequential failures is an important issue in industries, since the reliability and safety of a complex system depends, not only upon all failed states of the system components, but also upon the sequence of occurrence of those failures. In this paper, we present an alternative methodology for assessing sequential failures in a complex system. In previous research, the probability of sequential failures is computed based on tracking the markings of Petri net models and it is assumed that the time to failure of basic events follows an exponential distribution. To overcome the limitations of the current methods in applying Petri nets for assessment of sequential failures, the method presented in this paper employs the concept of counters used in Petri net simulation to perform sequential failure analysis and is developed based on evolution equations that describe the dynamics of the system. It is demonstrated with a sequential failure analysis example of an automated machining and assembly system. [ABSTRACT FROM AUTHOR]

This paper addresses two issues related to a hypothetical division in the Canadian Forces Geomatics Organization, which is devoted to the production of information in support of the U.S. National Imaging and Mapping Agency's (NIMA) Foundation Based Operations. First, the optimal configuration of the division is determined using queueing network and optimization principles. The second issue concerns the examination of the system behavior, given the system configuration. Bounding analysis, in classical queueing theory, is used to acquire insights into the problem. The contribution of the paper lies in the derivation of an alternative geomatics network architecture and the illustration that the L[sup ∞] norms on the expected steady-state waiting times between the two network representations, are equivalent. The objective of the revised architecture is that the theory of product-form solutions can be employed. In addition, the paper proposes a means to transform the nonlinear integer programming internet protocol (IP) problem to a linear IP, using approximation techniques and pre-tabulated probability-related functions. Finally, in anticipation of the surge and volume of geomatics information in support of Joint Vision 2010, this workforce and workflow analysis is of utmost importance. This paper provides a timely contribution toward the resolution of some of these military organizational issues. [ABSTRACT FROM AUTHOR]

This article presents information on various articles published in the November 2003 issue of the journal "IEEE Transactions on Systems, Man, and Cybernetics." The issue includes significant developments in the general area of mobile web services. The advent of wireless technologies, such as palmtops and cell-phones, creates the possibility of providing facilities on the spot, no matter where users are located. This issue includes six papers that were selected among the twenty-nine submissions in response to the journal's call for papers. Given the novelty of this research area, the issue also includes concept and visionary papers that outline key challenges and research directions.

Presents an introduction to the May 2005 issue of the journal "IEEE Transactions on Systems, Man, and Cybernetics."

The article presents information relevant to prospective authors including instructions on submitting a technical paper for publication, the required manuscript and illustrations styles, and details related to possible charges for voluntary and excess pages.

The article offers information related to the periodical "IEEE Transactions on Systems, Man and Cybernetics: Part A: Systems and Humans" including submission process of technical papers, manuscript style, and copyright.

The article offers information on the "IEEE Transactions on Systems, Man and Cybernetics: Part A: Systems & Humans" including the process for technical paper submission, manuscript style, and electronic publishing.

The article presents information for authors about the periodical "IEEE Transactions on Systems, Man and Cybernetics--Part A: Cybernetics," including the process for submission of a technical paper, electronic publishing and copyright.

A siphon-based algorithm for deadlock prevention of Petri nets called Algorithm H2 is proposed in the above paper. However, the illustrative examples for Algorithm H2 are incorrect because of the redundant weighted control (WC) places which control some marked siphons. This correspondence modifies the illustrative examples by removing the redundant control places and getting a maximally permissive control for the original net. As no WC place is presented in the modified examples, the examples cannot well illustrate Algorithm H2. [ABSTRACT FROM AUTHOR]

It was claimed recently in the paper by Li and Zhou that "a polynomial time algorithm for finding the set of elementary siphons in S3PRs is proposed, which avoids complete siphon enumeration." However, this is incorrect because Proposition 1 and Corollary 6 of the aforementioned paper, which lead to the claim, are both incorrect. In this correspondence paper, Proposition 1 and Corollary 6 are disproved. As a consequence, some claims of the aforesaid paper are denied. Two examples are presented to disprove some claims of the previously mentioned paper. [ABSTRACT FROM AUTHOR]

Managing human resources and skills for information technology (IT) presents a challenging task for executives, more so when new ITs are involved. Lack of familiarity with the technology, the learning curve associated with its incorporation, and the relative paucity of skilled personnel serve to alter the strategies for management of human resources and skills. This paper presents a system dynamics approach for examining alternative strategies for skill management and supporting decisions during the implementation of service-oriented architecture (SOA) in an organization. For projects involving SOA, the initial planning and implementation of the underlying architecture entail higher costs and slower delivery of initial SOA applications. The use of appropriate IT human resource management strategies for SOA projects is critical for successful SOA implementation. The complexity associated with the fluctuating demand for IT skills, coupled with the need for highly skilled senior architects and professional developers in SOA projects, as well as inevitable delays in skill acquisition, makes this a challenging task. This paper examines the impact of alternative staffing strategies under various environmental conditions and provides guidance for staffing decisions. Using a design science methodology, it employs system dynamics as a vehicle for allowing human resource managers to examine the impact of alternative staffing strategies under a variety of environmental conditions. [ABSTRACT FROM PUBLISHER]

This paper presents new warranty cost models subject to two types of warranty periods (warranty and postwarranty periods), minimal repairs, and various types of warranty policies including free repair/replacement warranty and prorata warranty for k-out-of-n systems. Two-dimensional warranty is applied to investigate the warranty cost using repair times and failure times. We obtain the long-run expected cost functions per unit time with respect to both the warranty and postwarranty periods by considering the aspects of both the manufacturer and the customer. This paper considers a periodic preventive maintenance (PM) policy with both corrective maintenance and PM and also determines three decision variables including warranty period, repair time limit, and periodical maintenance cycles, which minimize the long-run expected cost. Numerical examples are discussed to demonstrate the applicability of the methodologies, and results including the three optimum decision-variable solution and their corresponding long-run expected cost per unit are derived. [ABSTRACT FROM PUBLISHER]