ppxscal/embedding_network huggingface dataset:
Morphological segmentation of physiographic features from DEM
Authors: D. Sathymoorthy, R. Palanikumar, B. S. D. Sagar
Venue: International Journal of Remote Sensing (2007)

A terrain can be segmented into three predominant physiographic features; mountains, basins and piedmont slopes. The objective of this paper is to develop a mathematical morphological based algorithm to segment the terrain of a digital elevation model (DEM) into the three predominant physiographic features. Ultimate erosion is used to extract the peaks and pits of the DEM. Conditional dilation is performed on the peaks and pits of the DEM to extract the mountain and basin pixels, respectively. The unclassified pixels are assigned as piedmont slope pixels. The combination of the mountain, basin and piedmont slope regions form the physiographically segmented DEM. The effectiveness of the proposed physiographic segmentation algorithm is tested by implementing it on the Global Digital Elevation Model (GTOPO30) of the Great Basin, Nevada, USA.
On exploiting diversity and spatial reuse in relay-enabled wireless networks
Authors: Karthikeyan Sundaresan, Sampath Rangarajan
Venue: Proceedings of the 9th ACM international symposium on Mobile ad hoc networking and computing (2008)

Relay-enabled wireless networks (eg. WIMAX 802.16j) represent an emerging trend for the incorporation of multi-hop networking solutions for last-mile broadband access in next generation wireless networks. The adoption of more sophisticated access technologies such as OFDM (orthogonal frequency division multiplexing) coupled with the relay-induced two-hop nature, provides two key benefits to these networks in the form of diversity and spatial reuse gains. However, leveraging these benefits calls for more sophisticated solutions, among which, user scheduling forms a key component. We consider the specific problem of scheduling users with finite buffers on the multiple OFDM carriers (channels over the two hops of the relay-enabled network. We propose scheduling algorithms that help leverage diversity and spatial reuse gains from these networks. We show that even the scheduling problem to exploit diversity gains alone is NP-hard and provide both theoretically and practically efficient polynomial-time algorithms with approximation guarantees. Building on the diversity solutions, we also propose an efficient polynomial-time scheduling algorithm for exploiting both spatial reuse as well as diversity. The proposed solutions are evaluated to highlight the relative significance of diversity and spatial reuse gains with respect to varying network conditions.
Large atmospheric computation on the earth simulator: The LACES project
Authors: Michel Desgagné, Ron McTaggart-Cowan, Wataru Ohfuchi, Gilbert Brunet, Peter Yau, John Gyakum, Yuki Furukawa, Michel Valin
Venue: Scientific Programming (2006)

The Large Atmospheric Computation on the Earth Simulator (LACES) project is a joint initiative between Canadian and Japanese meteorological services and academic institutions that focuses on the high resolution simulation of Hurricane Earl (1998). The unique aspect of this effort is the extent of the computational domain, which covers all of North America and Europe with a grid spacing of 1 km. The Canadian Mesoscale Compressible Community (MC2) model is shown to parallelize effectively on the Japanese Earth Simulator (ES) supercomputer; however, even using the extensive computing resources of the ES Center (ESC), the full simulation for the majority of Hurricane Earl's lifecycle takes over eight days to perform and produces over 5.2 TB of raw data. Preliminary diagnostics show that the results of the LACES simulation for the tropical stage of Hurricane Earl's lifecycle compare well with available observations for the storm. Further studies involving advanced diagnostics have commenced, taking advantage of the uniquely large spatial extent of the high resolution LACES simulation to investigate multiscale interactions in the hurricane and its environment. It is hoped that these studies will enhance our understanding of processes occurring within the hurricane and between the hurricane and its planetary-scale environment.
A comparison of model transformation tools: Application for Transforming GRAI Extended Actigrams into UML Activity Diagrams
Authors: Ramzi Ben Salem, Reyes Grangel, Jean-Pierre Bourey
Venue: Computers in Industry (2008)

Integration of information and manufacturing systems is one of the great achievements of Enterprise Modelling. However, new factors, such as the fast evolution of Information and Communication Technologies (ICT) or the need to set up alliances among different types of enterprises quickly in order to benefit from market opportunities, are causing new types of problems, like interoperability, to appear in the Enterprise Modelling context. This paper shows how a model-driven approach can be useful to solve interoperability problems using model transformations. In particular, the transformation of GRAI Extended Actigrams into UML Activity Diagrams is explored using three different model transformation tools.
Formal datapath representation and manipulation for implementing DSP transforms
Authors: Peter A. Milder, Franz Franchetti, James C. Hoe, Markus Püschel
Venue: Proceedings of the 45th annual Design Automation Conference (2008)

We present a domain-specific approach to representing datapaths for hardware implementations of linear signal transform algorithms. We extend the tensor structure for describing linear transform algorithms, adding the ability to explicitly characterize two important dimensions of datapath architecture. This representation allows both algorithm and datapath to be specified within a single formula and gives the designer the ability to easily consider a wide space of possible datapaths at a high level of abstraction. We have constructed a formula manipulation system based on this representation and have written a compiler that can translate a formula into a hardware implementation. This enables an automatic "push button" compilation flow that produces a register transfer level hardware description from high-level datapath directives and an algorithm (written as a formula). In our experimental results, we demonstrate that this approach yields efficient designs over a large tradeoff space.
Efficient NC algorithms for set cover with applications to learning and geometry
Authors: B. Berger, J. Rompel
Venue: Proceedings of the 30th Annual Symposium on Foundations of Computer Science (1989)

NC approximation algorithms are given for the unweighted and weighted set cover problems. The algorithms use a linear number of processors and give a cover that has at most log n times the optimal size/weight, thus matching the performance of the best sequential algorithms. The set cover algorithm is applied to learning theory, providing an NC algorithm for learning the concept class obtained by taking the closure under finite union or finite intersection of any concept class of finite VC dimension which has an NC hypothesis finder. In addition, a linear-processor NC algorithm is given for a variant of the set cover problem and used to obtain NC algorithms for several problems in computational geometry.
Hardware/software partitioning and simulation with SystemC
Authors: Richard Gallery, Deepesh M. Shakya
Venue: Proceedings of the 2nd WSEAS International Conference on Electronics, Control and Signal Processing (2003)

This paper gives an overview of how the speed of simulation of Video/Graphics subsystem can be increased with SystemC [1][5][6]. Also, an idea of partitioning hardware and software at instruction level and the simulation framework to support this partitioning has been introduced. The simulation of each design space is conducted at the transaction level and the partitioning decision, which is effectively a selection of suitable design space, is made on the basis of the number of instructions, resource wastage factor and the hardware cost involved in the design space.
A probabilistic trust model for semantic peer to peer systems
Authors: G. H. Nguyen, P. Chatalic, M. C. Rousset
Venue: Proceedings of the 2008 international workshop on Data management in peer-to-peer systems (2008)

Semantic peer to peer (P2P) systems are fully decentralized overlay networks of people or machines (called peers) sharing and searching varied resources (documents, videos, photos, data, services) based on their semantic annotations using ontologies. They provide a support for the emergence of open and decentralized electronic social networks, in which no central or external authority can control the reliability of the peers participating to the network. This lack of control may however cause some of the results provided by some peers to be unsatisfactory, because of inadequate or obsolete annotations. In this paper, we propose a probabilistic model to handle trust in a P2P setting. It supports a local computation and a simple form of propagation of the trust of peers into classes of other peers. We claim that it is well appropriate to the dynamics of P2P networks and to the freedom of each peer within the network to have different viewpoints towards the peers with which it interacts.
Adaptive load sharing for network processors
Authors: Lukas Kencl, Jean-Yves Le Boudec
Venue: IEEE/ACM Transactions on Networking (TON) (2008)

A novel scheme for processing packets in a router is presented that provides load sharing among multiple network processors distributed within the router. It is complemented by a feedback control mechanism designed to prevent processor overload. Incoming traffic is scheduled to multiple processors based on a deterministic mapping. The mapping formula is derived from the robust hash routing (also known as the highest random weight--HRW) scheme, introduced in K. W. Ross, IEEE Network, 11(6), 1997, and D. G. Thaler et al., IEEE Trans. Networking, 6(1), 1998. No state information on individual flow mapping has to be stored, but for each packet, a mapping function is computed over an identifier vector, a predefined set of fields in the packet. An adaptive extension to the HRW scheme is provided to cope with biased traffic patterns. We prove that our adaptation possesses the minimal disruption property with respect to the mapping and exploit that property to minimize the probability of flow reordering. Simulation results indicate that the scheme achieves significant improvements in processor utilization. A higher number of router interfaces can thus be supported with the same amount of processing power.
Computability of the Spectrum of Self-Adjoint Operators and the Computable Operational Calculus
Authors: Ruth Dillhage
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2008)

Self-adjoint operators and their spectra play a crucial role in analysis and physics. Therefore, it is a natural question whether the spectrum of a self-adjoint operator and its eigenvalues can be computed from a description of the operator. We prove that given a ''program'' of the operator one can obtain positive information on the spectrum as a compact set in the sense that a dense subset of the spectrum can be enumerated and a bound on the set can be computed. This generalizes some non-uniform results obtained by Pour-El and Richards, which imply that the spectrum of any computable self-adjoint operator is a recursively enumerable compact set. Additionally, we show that the eigenvalues of self-adjoint operators can be computed in the sense that we can compute a list of indices such that those elements of the already computed dense subset of the spectrum, whose indices are not enumerated in this list, form the set of eigenvalues. Beside these main results we prove some computability results about the operational calculus, which we need in our proofs.
Model-based behavioral attestation
Authors: Masoom Alam, Xinwen Zhang, Mohammad Nauman, Tamleek Ali, Jean-Pierre Seifert
Venue: Proceedings of the 13th ACM symposium on Access control models and technologies (2008)

Remote attestation is an important characteristic of trusted computing technology which provides reliable evidence that a trusted environment actually exists. Existing approaches for the realization of remote attestation measure the trustworthiness of a target platform from its binaries, configurations, properties or security policies. All these approaches are low-level attestation techniques only, and none of them define what a trusted behavior actually is and how to specify it. In this paper, we present a novel approach where the trustworthiness of a platform is associated with the behavior of a policy model. In our approach, the behavior of a policy model is attested rather than a software or hardware platform. Thus, the attestation feature is not tied to a specific software or hardware platform, or to a particular remote attestation technique, or to an individual type of security policy. We select usage control (UCON) as our target policy model as it is a comprehensive and exible model. We propose a framework to identify, specify, and attest different behaviors of UCON.
Cooperative packet relaying model for wireless ad hoc networks
Authors: Lu Yan, Stephen Hailes
Venue: Proceeding of the 1st ACM international workshop on Foundations of wireless ad hoc and sensor networking and computing (2008)

In wireless ad hoc networks such as mobile ad hoc networks and sensor networks, most of the functions (routing, mobility management, and security) must rely on cooperation between nodes. Every node in these networks is both end host (it generates its own data and routing traffic) and infrastructure (it forwards traffic for others), but rational nodes have no incentive to cooperatively forward traffic for others, since this kind of forwarding is not costless. Thus, we are motivated to use game theory to analyze cooperative mechanisms, and derive incentive strategies enforcing cooperation in forwarding. Unlike traditional approaches, in this paper, we introduce a novel and interdisciplinary simulation-based analysis scheme to the networking community in game-theoretic settings. Moreover, we investigate noise models and show some counterintuitive simulation results in presence of noise.
A scalable dual-clock FIFO for data transfers between arbitrary and haltable clock domains
Authors: Ryan W. Apperson, Zhiyi Yu, Michael J. Meeuwsen, Tinoosh Mohsenin, Bevan M. Baas
Venue: IEEE Transactions on Very Large Scale Integration (VLSI) Systems (2007)

A robust, scalable, and power efficient dual-clock first-input first-out (FIFO) architecture which is useful for transferring data between modules operating in different clock domains is presented. The architecture supports correct operation in applications where multiple clock cycles of latency exist between the data producer, FIFO, and the data consumer; and with arbitrary clock frequency changes, halting, and restarting in either or both clock domains. The architecture is demonstrated in both a 0.18-µm CMOS full. custom design and a 0.18-µm CMOS standard cell design used in a globally asynchronous locally synchronous array processor. It achieves 580-MHz operation and 10.3-mW power dissipation while performing simultaneous FIFO READ and WRITE operations at 1.8 V.
On Nash---Cournot oligopolistic market equilibrium models with concave cost functions
Authors: Le D. Muu, V. H. Nguyen, N. V. Quy
Venue: Journal of Global Optimization (2008)

We consider Nash---Cournot oligopolistic market equilibrium models with concave cost functions. Concavity implies, in general, that a local equilibrium point is not necessarily a global one. We give conditions for existence of global equilibrium points. We then propose an algorithm for finding a global equilibrium point or for detecting that the problem is unsolvable. Numerical experiments on some randomly generated data show efficiency of the proposed algorithm.
Personal vs non-personal blogs: initial classification experiments
Authors: Erik Elgersma, Maarten de Rijke
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

We address the task of separating personal from non-personal blogs, and report on a set of baseline experiments where we compare the performance on a small set of features across a set of five classifiers. We show that with a limited set of features a performance of up to 90% can be obtained.
Scalable Data Gathering for Real-Time Monitoring Systems on Distributed Computing
Authors: Yoshikazu Kamoshida, Kenjiro Taura
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

Real-time monitoring is increasingly becoming important in various scenes of large scale, multi-site distributed/parallel computing, e.g, understanding behavior of systems, scheduling resources, and debugging applications. Dedicated networks on inter-site communications are rarely available for the monitoring purposes. Therefore, for real-time monitoring systems, reducing communication cost is important to handle a large number of nodes with limited network resources. We implemented a real-time Grid monitoring system called VGXP, with techniques for low cost data gathering. It tries to send only diffs to recent data, and adapts to the requested data freshness and tolerable errors to minimize required communication. We evaluate monitoring overheads of the proposed method on a distributed environment consisting of 8-sites with 500 nodes. In a realistic setting where the sampling interval is set to 0.5 seconds and the tolerable error to 2%, the CPU usage of the server to gather data from all nodes was 0.2% and the transfer rate was less than 5kbps. The transfer rate did not exceed 50kbps even if we gather a detailed per-process statistics.
Impact of Multipath Interference on the Performance of an UWB Fast Acquisition System for Ranging in an Indoor Wireless Channel
Authors: Yassine Salih Alj, Charles Despins, Sofiène Affes
Venue: Proceedings of the Communication Networks and Services Research Conference (2008)

In this paper, the effects of multipath interferences on the performance of a multiuser ultra-wideband (UWB) fast acquisition system operating in an underground indoor fading channel are evaluated and compared. Various pulse shapes are considered with different scenarios of interference and Gaussian noise in extensive Monte-Carlo simulations. The results show the 6th order Gaussian derivative as the most suitable pulse shape for this new UWB fast acquisition system suggested for ranging in a peculiar confined environment, offering very acceptable positioning error range at high levels of noise and interference, while also yielding greatly reduced complexity and acquisition time.
Syntactic segmentation of function graph type of curves
Authors: Marzena Bielecka
Venue: Machine Graphics Vision International Journal (2007)

In this paper structural analysis of patterns being a special type of curves is presented. The recognized objects are segmented according to their structural properties into primitive patterns representing generic shapes. Then, an algebraic formula describing the structure of the analyzed curve is created. The description is unique.
Cooperative production networks: multiagent modeling and planning
Authors: Péter Egri, József Váncza
Venue: Acta Cybernetica (2007)

Consumer goods are mainly produced in multiple steps through a long process. These steps are often done by separate, independent production nodes (enterprises), linked by supply chains. The networks of enterprises-- where members have their own objectives and act in an autonomous, rational way to reach their goals--can be naturally modeled by agent-based methodology. The inner structure of each enterprise is similar in the sense that it contains separated planning functions (e.g., production-, inventory-, capacity planning). While the operation inside an enterprise can be controlled centrally, the interaction between the nodes could be synchronized only by negotiation and coordination. Coordination can be based on protocols which regulate information, material and financial flows alike. In this paper we expose an agent-based organizational model of production networks and suggest some planning algorithms which can handle the uncertainty of demand. In addition, we outline the first results of our ongoing research, an analysis of the asymmetric information case and an appropriate coordination mechanism.
On a new iterative method for solving linear systems and comparison results
Authors: Yan-Fei Jing, Ting-Zhu Huang
Venue: Journal of Computational and Applied Mathematics (2008)

In Ujevic [A new iterative method for solving linear systems, Appl. Math. Comput. 179 (2006) 725-730], the author obtained a new iterative method for solving linear systems, which can be considered as a modification of the Gauss-Seidel method. In this paper, we show that this is a special case from a point of view of projection techniques. And a different approach is established, which is both theoretically and numerically proven to be better than (at least the same as) Ujevic's. As the presented numerical examples show, in most cases, the convergence rate is more than one and a half that of Ujevic.
Digital map restructuring method based on implicit intentions extracted from users' operations
Authors: Daisuke Kitayama, Takahiro Teratani, Kazutoshi Sumiya
Venue: Proceedings of the 2nd international conference on Ubiquitous information management and communication (2008)

In this paper, we propose a method of enhancing digital map interface by reflecting users' intentions by means of automatically restructured maps. Extracted from the sequences of the users' map operations (zooming, centering, and panning), the users' intentions determine the types of objectives based on the sequence patterns or the semantic relation between place's names. We define operation chunk mechanism, which expresses the meaning of the operation sequences, and the semantic relation, which expresses the meaning of the relation between two place's names. We also explain the restructuring function mechanism, by which the users' intentions are described, combining the operation chunks and the semantic relations. We have developed a prototype system based on this method and evaluated the appropriateness of the abovementioned definitions. The experimental results show that the restructuring function mechanism is defined appropriately, and that the automatically restructured map is sufficiently effective.
Exploring agile
Authors: David Gelperin
Venue: Proceedings of the 2008 international workshop on Scrutinizing agile practices or shoot-out at the agile corral (2008)

Bob attempts to figure out exactly what Agile development is and where it works by analyzing the Agile Manifesto and its supporting principles. He proposes changes to some troubling statements.
On the predictability of coupled automata: an allegory about chaos
Authors: S. Buss, C. H. Papadimitriou
Venue: Proceedings of the 31st Annual Symposium on Foundations of Computer Science (1990)

The authors show a sharp dichotomy between systems of identical automata with symmetric global control whose behavior is easy to predict and those whose behavior is hard to predict. The division pertains to whether the global control rule is invariant with respect to permutations of the states of the automaton. It is also shown that testing whether the global control rule has this invariance property is an undecidable problem. It is argued that there is a natural analog between complexity in the present model and chaos in dynamical systems.