ppxscal/embedding_network huggingface dataset:
Landscape dynamics risk management in Northern Apennines (Italy)
Authors: F. Bianchi, F. Catani
Venue: Development and application of computer techniques to environmental studies (2002)

The Riomaggiore catchment is a sub-watershed of the Reno river basin, located in the Northern Apennines between Florence and Bologna. The whole area shows complex interactions between the environment and human activities: hillslope processes, mainly soil erosion and landsliding, are very widespread and overlap in many cases with settlements and infrastructures. Under such conditions specialised instruments are needed for a correct management of the environmental sustainability.This paper presents the results of the application of an environmental accounting model for the choice of the optimal management strategy at a local government level. The accounting model is in turn made up of three different components, i) a soil erosion prediction scheme based on a distributed version of the Universal Soil Loss Erosion USLE, ii) a landsliding assessment module in which the relative probability of movement depends on a series of physical parameters weighted by an artificial neural network and iii) a simple economic model taking into account value and production losses expected as a consequence of surface processes.The different output of the simulation phase, generated with varying parameters and conditions, represent in average the whole spectrum of the possible risk scenarios. These last constitute the input of the environmental accounting model that can be used to validate hypotheses, rank the different scenarios and guide the decision makers toward the best prevention measures in the territorial planning phase. The same approach can be used for the real-time management of emergency situations concerning natural hazards.
The Solo operating system: a concurrent Pascal program
Authors: Per Brinch Hansen
Venue: The origin of concurrent programming: from semaphores to remote procedure calls (2002)

This is a description of the single-user operating system Solo written in the programming language Concurrent Pascal. It supports the development of Sequential and Concurrent Pascal programs for the PDP 11/45 computer. Input/output are handled by concurrent processes. Pascal programs can call one another recursively and pass arbitrary parameters among themselves. This makes it possible to use Pascal as a job control language. Solo is the first major example of a hierarchical concurrent program implemented in terms of abstract data types (classes, monitors and processes) with compile-time control of most access rights. It is described here from the user's point of view as an introduction to another paper describing its internal structure.
Agent-based modelling and the environmental complexity thesis
Authors: Anil K. Seth
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

A variation of Godfrey-Smith's 'environmental complexity thesis' is described which draws together two broad themes; the relation of functional properties of behaviour to environmental structure, and the distinction between behavioural and mechanistic levels of description. The specific idea defended here is that behavioural and/or mechanistic complexity can be understood in terms of mediating well-adapted responses to environmental variability. Particular attention is paid to the value of agent-based modelling within this framework.
The next revolution: vehicle user-interfaces and the global rider/driver experience
Authors: Deborah A. Boehm-Davis, Aaron Marcus, Paul Allan Green, Hideki Hada, David Wheatley
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

The driver/rider experience is a major development in mobile user-interface (UI) design worldwide, similar in scale to the first introduction of personal computers to the desktop. Most automobile manufacturers seeking to develop smart cars have relatively little experience with advanced software-based UIs and information visualization (IV). This panel introduces essential issues of vehicle UI design to the CHI community and offers competing views about the most important issues affecting usability, safety, appeal, functionality, information, and entertainment.
Chiral effects on optical solitons
Authors: H. Torres-Silva, M. Zamorano
Venue: Mathematics and Computers in Simulation (2003)

A basic equation, describing the temporal evolution of fields in a chiral medium with Kerr non-linearity is used to study the effects resulting from the combined action of chirality and non-linearity on optical solitons. The spatial chirality effect is characterized through the Born-Fedorov formalism. Simulations are based in the split-step Fourier method and the numerical results show the chiral effects on solitons with circular and mixed polarization.
An improved method for Dodin's approach to approximate the distribution functions in stochastic networks
Authors: S. M. T. Fatemi Ghomi, E. Teimouri
Venue: Iranian Journal of Science and Technology (2001)

In this paper, Dodin's approach to approximate the distribution function in stochastic networks is improved. For this purpose, an algorithm is presented which has benefits of both approximation and simulation approaches. The method has much reduced the errors due to the assumption of independency of activities completion times in the internal nodes of the network, and produces excellent results very close to the real values. Numerical examples provided for different size of networks, prove the high efficiency and has sufficient applicability even for large networks.
Mobile processes: a commented bibliography
Authors: Silvano Dal Zilio
Venue: Modeling and verification of parallel processes (2001)

We propose a short bibliographic survey of calculi for mobile processes. Contrasting with other similar exercises, we consider two related, but distinct, notions of mobile processes, namely labile processes, which can exhibit dynamic changes in their interaction structure, as modelled in the π-calculus of Milner, Parrow and Walker for example, and motile processes, which can exhibit motion, as modelled in the ambient calculus of Cardelli and Gordon. A common characteristic of the algebraic frameworks presented in this paper is the use of names as first class values and the support for the dynamic generation of new, fresh names.
Visual cluster validity for prototype generator clustering models
Authors: Richard J. Hathaway, James C. Bezdek
Venue: Pattern Recognition Letters (2003)

Conventional cluster validity techniques usually represent all the validity information available about a particular clustering by a single number. The display method introduced here uses images generated from the results of any prototype generator clustering algorithm to do cluster validation.
Combined dynamic voltage scaling and adaptive body biasing for lower power microprocessors under dynamic workloads
Authors: Steven M. Martin, Krisztian Flautner, Trevor Mudge, David Blaauw
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Dynamic voltage scaling (DVS) reduces the power consumption of processors when peak performance is unnecessary. However, the achievable power savings by DVS alone is becoming limited as leakage power increases. In this paper, we show how the simultaneous use of adaptive body biasing (ABB) and DVS can be used to reduce power in high-performance processors. Analytical models of the leakage current, dynamic power, and frequency as functions of supply voltage and body bias are derived and verified with SPICE simulation. We then show how to determine the correct trade-off between supply voltage and body bias for a given clock frequency and duration of operation. The usefulness of our approach is evaluated on real workloads obtained using real-time monitoring of processor utilization for four applications. The results demonstrate that application of simultaneous DVS and ABB results in an average energy reduction of 48% over DVS alone.
Behaviour selection on a mobile robot using W-learning
Authors: A. O. Martin Hallerdal, John C. T. Hallam
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

A common approach in complex reinforcement learning tasks is to divide the problem into functional parts, or behaviours, and then to assign a sub-agent to solve each task. The action selection problem then becomes to negotiate between sub-agents with conflicting desires. W-learning is a method whereby agents build up W-values in each state that indicate how important that state is for that agent. These values are then used as basis for selecting agents. In this paper we present the first results, as far as we know, of applying W-learning on a mobile robot in solving a task in the real world. Results from the experiments are presented and the suitability of W-learning for real world robot tasks is discussed.
A simulation and design of experiments modeling approach to minimize building maintenance costs
Authors: Yasser M. Dessouky, Adam Bayer
Venue: Computers and Industrial Engineering (2002)

In this paper, a methodology is presented to integrate maintenance policy selection into the design and construction process. A simulation model identifies the quality attributes for the maintenance process to determine the funds to be allocated to maintenance in the building's design and construction phases in order to minimize maintenance costs. The output of the simulation model is a value of excess labor hours above a specified level. The simulation output is used in a 24 factorial experimental design to identify the quality attributes that have the greatest impact on costs. A Taguchi loss function based on the minimized quantity of excess labor hours and historical expenditures provides the tool to relate maintenance priorities to design and construction. Quality characteristics for maintenance are modified in the feedback process and result in a more maintainable building.
Enticing online consumers: an extended technology acceptance perspective
Authors: Lei-da Chen, Mark L. Gillenson, Daniel L. Sherrell
Venue: Information and Management (2002)

The business-to-consumer aspect of electronic commerce (EC) is the most visible business use of the World Wide Web (www). A virtual store allows companies to provide product information and offer direct sales to their customers through an electronic channel. The fundamental problem motivating this study is that: in order for a virtual store to compete effectively with both physical stores and other online retailers, there is an urgent need to understand the factors that entice consumers to use it. This research attempted to provide both theoretical and empirical analyses to explain consumers' use of a virtual store and its antecedents.By applying the technology acceptance model (TAM) and innovation diffusion theory (IDT), this research took an extended perspective to examine consumer behavior in the virtual store context. The data from a survey of online consumers was used empirically to test the proposed research model. Confirmatory factor analysis (CFA) was performed to examine the reliability and validity of the measurement model, and the structural equation modeling (SEM) technique was used to evaluate the causal model. The implication of the work to both researchers and practitioners is discussed.
Theoretical and practical validation of combined BEM/FEM substrate resistance modeling
Authors: E. Schrik, P. M. Dewilde, N. P. van der Meijs
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

In mixed-signal designs, substrate noise originating from the digital part can seriously influence the functionality of the analog part. As such, accurately modeling the properties of the substrate as a noise-propagator is becoming ever more important. A model can be obtained through the Finite Element Method (FEM) or the Boundary Element Method (BEM). The FEM performs a full 3D discretization of the substrate, which makes this method very accurate and flexible but also slow. The BEM only discretizes the contact areas on the boundary of the substrate, which makes it less flexible, but significantly faster. A combination between BEM and FEM can be efficient when we need flexibility and speed at the same time. This paper briefly describes the BEM and the FEM and their combination, but mainly concentrates on the theoretical validation of the combined method and the experimental verification through implementation in the SPACE layout to circuit extractor and comparison with commercial BEM and FEM tools.
Optimal Load Balancing on Distributed Homogeneous Unreliable Processors
Authors: Zhen Liu, Rhonda Righter
Venue: Operations Research (1998)

We consider optimal load balancing in a distributed computing environment consisting of homogeneous unreliable processors. Each processor receives its own sequence of tasks from outside users, some of which can be redirected to the other processors. Processing times are independent and identically distributed with an arbitrary distribution. The arrival sequence of outside tasks to each processor may be arbitrary as long as it is independent of the state of the system. Processors may fail, with arbitrary failure and repair processes that are also independent of the state of the system. The only information available to a processor is the history of its decisions for routing work to other processors, and the arrival times of its own arrival sequence. We prove the optimality of the round-robin policy, in which each processor sends all the tasks that can be redirected to each of the other processors in turn. We show that, among all policies that balance workload, round robin stochastically minimizes the nth task completion time for all n, and minimizes response times and queue lengths in a separable increasing convex sense for the entire system. We also show that if there is a single centralized controller, round-robin is the optimal policy, and a single controller using round-robin routing is better than the optimal distributed system in which each processor routes its own arrivals. Again "optimal" and "better" are in the sense of stochastically minimizing task completion times, and minimizing response time and queue lengths in the separable increasing convex sense.
A novel generic graph model for traffic grooming in heterogeneous WDM mesh networks
Authors: Hongyue Zhu, Hui Zang, Keyao Zhu, Biswanath Mukherjee
Venue: IEEE/ACM Transactions on Networking (TON) (2003)

As the operation of our fiber-optic backbone networks migrates from interconnected SONET rings to arbitrary mesh topology, traffic grooming on wavelength-division multiplexing (WDM) mesh networks becomes an extremely important research problem. To address this problem, we propose a new generic graph model for traffic grooming in heterogeneous WDM mesh networks. The novelty of our model is that, by only manipulating the edges of the auxiliary graph created by our model and the weights of these edges, our model can achieve various objectives using different grooming policies, while taking into account various constraints such as transceivers, wavelengths, wavelength-conversion capabilities, and grooming capabilities. Based on the auxiliary graph, we develop an integrated traffic-grooming algorithm (IGABAG) and an integrated grooming procedure (INGPROC) which jointly solve several traffic-grooming subproblems by simply applying the shortest-path computation method. Different grooming policies can be represented by different weight-assignment functions, and the performance of these grooming policies are compared under both nonblocking scenario and blocking scenario. The IGABAG can be applied to both static and dynamic traffic grooming. In static grooming, the traffic-selection scheme is key to achieving good network performance. We propose several traffic-selection schemes based on this model and we evaluate their performance for different network topologies.
Performance Analysis and Optimization of Assemble-to-Order Systems with Random Lead Times
Authors: Jing-Sheng Song, David D. Yao
Venue: Operations Research (2002)

We study a single-product assembly system in which the final product is assembled to order whereas the components (subassemblies) are built to stock. Customer demand follows a Poisson process, and replenishment lead times for each component are independent and identically distributed random variables. For any given base-stock policy, the exact performance analysis reduces to the evaluation of a set ofM/ G/8 queues with a common arrival stream. We show that unlike the standardM/ G/8 queueing system, lead time (service time) variability degrades performance in this assembly system. We also show that it is desirable to keep higher base-stock levels for components with longer mean lead times (and lower unit costs). We derive easy-to-compute performance bounds and use them as surrogates for the performance measures in several optimization problems that seek the best trade-off between inventory and customer service. Greedy-type algorithms are developed to solve the surrogate problems. Numerical examples indicate that these algorithms provide efficient solutions and valuable insights to the optimal inventory/service trade-off in the original problems.
Fleet dynamics and information exchange simulation modeling with artificial neural networks
Authors: Michel Dreyfus-Leon, Daniel Gaertner
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

A fishery is simulated in which 20 artificial vessels learn through an artificial neural network to make decisions to search for fish among the fishing grounds available. The simulation model keeps several characteristics of a purse seine tuna fishery. Vessels strategies are chosen by the artificial neural network, where the elements considered for decision are: time searching and performance in an area, knowledge of the quality of several fishing grounds, presence of other vessels and trip duration. In particular an analysis of the effects of sharing information between vessels is done. Results show an effect in performance as well as a bias in the fish abundance index estimates calculated from data from the artificial vessels fishing as a group.
A Performance Comparison of Code Acquisition Techniques in DS-CDMA System
Authors: Bub-Joo Kang, Il-Kyoo Lee
Venue: Wireless Personal Communications: An International Journal (2003)

This paper compares parallel acquisition with hybrid acquisition in terms of mean acquisition time in code acquisition system of forward link and reverse link of direct sequence code division multiple access (DS-CDMA) system. The mean acquisition time of the hybrid and parallel acquisitions is derived from the distribution of the multiple correct code-phase offsets. Especially, the mean acquisition time of the hybrid acquisition scheme is derived by considering both case 1 (the correct code-phase offsets are included in one subset) and case 2 (the correct code-phase offsets exist at the boundary of two subsets), which are caused by the distribution of the correct code-phase offsets in the subset. Results are provided for the performance comparison between hybrid acquisition and parallel acquisition under the same hardware complexity in the forward and reverse links. In our performance evaluation of code acquisition in DS-CDMA system, the hybrid acquisition shows a better performance than the parallel acquisition in terms of mean acquisition time of the both links in the frequency-selective Rayleigh fading channel.
Digital promises
Authors: Arun Kumar Tripathi
Venue: Ubiquity (2002)

The prospect of living our lives online may not be so attractive after all
Lower bounds for dynamic transitive closure, planar point location, and parantheses matching
Authors: Thore Husfeldt, Theis Rauhe, Søren Skyum
Venue: Nordic Journal of Computing (1996)

We give a number of new lower bounds in the cell probe model with logarithmic cell size, which entails the same bounds on the random access computer with logarithmic word size and unit cost operations.We study the signed prefix sum problem: given a string of length n of Os and signed ls, compute the sum of its ith prefix during updates. We show a lower bound of Ω(log n/log log n) time per operations, even if the prefix sums are bounded by log n/log log n during all updates. We also show that if the update time is bounded by the product of the worst-case update time and the answer to the query, then the update time must be Ω(√(log n/ log log n)).These results allow us to prove lower bounds for a variety of seemingly unrelated dynamic problems. We give a lower bound for the dynamic planar point location in monotone subdivisions of Ω(log n/ log log n) per operation. We give a lower bound for dynamic transitive closure on upward planar graphs with one source and one sink of Ω(log n/(log log n)2) per operation. We give a lower bound of Ω(√(log n/log logn)) for the dynamic membership problem of any Dyck language with two or more letters. This implies the same lower bound for the dynamic word problem for the free group with k generators. We also give lower bounds for certain range searching variants and for the dynamic prefix majority and prefix equality problems.
One-dimensional Ginzburg-Landau model of superconductivity with pinning effects
Authors: Wanghui Yu
Venue: Nonlinear Analysis: Theory, Methods Applications (2003)

We study one-dimensional Ginzburg-Landau models of superconductivity with normal conductors on the sides of the interval occupied by the superconductor materials. The most interesting features of these problems are pinning phenomena analogous to those of vortex for higher-dimensional problems. We investigate behaviors of the minimizers as the Ginzburg-Landau parameter tends to infinity and prove that, with pinning on one side, the minimizers tend to an asymmetric limit, while, with pinning symmetrically on both sides, the minimizers tend to a symmetric limit.
Basestation collaboration in Bluetooth voice networks
Authors: Jingxin Xue, Terence D. Todd
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2003)

In the near future Bluetooth may be embedded into many different types of mobile and portable devices [IEEE Personal Commun. 7 (1) (2000)]. This connectivity will enable a variety of future picocellular services such as real-time voice and data [Specification of the Bluetooth System 1.0b., Bluetooth Special Interest Group, 1999]. In this paper, we consider several Bluetooth-based telephony access point designs. Since the number of SCO links per Bluetooth node is very limited, the designs consider the use of multiple overlapping Bluetooth basestations or module coverage areas. The first scheme is a direct implementation of the telephony profile where the Bluetooth basestations/modules operate independently, without any coordination. The paper proposes several schemes which use a variety of techniques for reducing the call blocking rate using real-time communication between the basestations or Bluetooth modules. It is shown that significant improvements in blocking performance are possible using this approach. A constraint on the design of high-capacity voice access points is the potential packet loss experienced by overlapping SCO transmissions. The paper includes a worse-case characterization and discussion of Bluetooth's shortcomings in this regard.