ppxscal/embedding_network huggingface dataset:
On the existence of maximal elements: An impossibility theorem
Authors: Nikolai S. Kukushkin
Venue: Discrete Applied Mathematics (2008)

All sufficient (as well as necessary) conditions for a binary relation on a metric space to admit a maximal element on every nonempty compact subset of its domain that have been found so far in the literature can be expressed as the prohibition of certain ''configurations.'' No condition of this form could be necessary and sufficient simultaneously.
Model Predictive Feedback Control for QoS Assurance in Webservers
Authors: Cheng-Zhong Xu, Bojin Liu, Jianbin Wei
Venue: Computer (2008)

The eQoS framework represents a first step in a systematic approach to provisioning user-perceived page-view response time differentiation and assurance. It deploys a model predictive feedback controller approach to adjust the processing rate allocated to each class of requests dynamically in response to measured performance deviation.
Not just correct, but correct and fast: a look at one of Jim Gray's contributions to database system performance
Authors: David J. DeWitt, Charles Levine
Venue: ACM SIGMOD Record (2008)

This paper examines Jim Gray's role in the specification of the debit/credit benchmark. The publication of this benchmark in a 1985 paper launched a benchmark war among the vendors that resulted in dramatic improvements in database system performance in the years following its publication. It was the genesis of the TPC, an industry consortium which has reshaped the benchmark landscape. Descendents of this benchmark continue to this day to be an important metric of modern transaction processing systems.
Z-transformations on proper and symmetric cones: Z-transformations
Authors: M. Seetharama Gowda, Jiyuan Tao
Venue: Mathematical Programming: Series A and B (2008)

Motivated by the similarities between the properties of Z-matrices on $$R^{n}_+$$ and Lyapunov and Stein transformations on the semidefinite cone $$\mathcal {S}^n_+$$, we introduce and study Z-transformations on proper cones. We show that many properties of Z-matrices extend to Z-transformations. We describe the diagonal stability of such a transformation on a symmetric cone by means of quadratic representations. Finally, we study the equivalence of Q and P properties of Z-transformations on symmetric cones. In particular, we prove such an equivalence on the Lorentz cone.
Distributed situation awareness in an Airborne Warning and Control System: application of novel ergonomics methodology
Authors: Rebecca Stewart, Neville A. Stanton, Don Harris, Chris Baber, Paul Salmon, Mel Mock, Kerry Tatlock, Linda Wells, Alison Kay
Venue: Cognition, Technology and Work (2008)

This paper applies a distributed theory of situation awareness based upon the analysis of interactions between agents (both human and non-human) in an Airborne Warning and Control System (Boeing E3D Sentry). The basic tenet of this approach is that agents within a system each hold their own component(s) of situation awareness, which may be very different from, but compatible with, other agent&#x2019;s view of the situation. However, it is argued that it is not always necessary to have complete sharing of this awareness, as different system agents have different purposes. Situation awareness is regarded as a dynamic and collaborative process that binds agents together on tasks on a moment-by-moment basis. Situation awareness is conceptualised as residing at a system, not an individual level. Data were collected from crew-members in theE3D during a series of simulated air battles. These data pertained to task structure, communications between the crew and the collection and analysis of crew actions at critical decision points. All phases of operations were considered. From these data propositional networks were developed in which key knowledge objects were identified. Analysis of these networks clearly shows how the location and nature of distributed situation awareness changes across agents with regard to the phase of operation/air battle.
Next-generation power-aware design
Authors: Takayasu Sakurai
Venue: Proceeding of the 13th international symposium on Low power electronics and design (2008)

Reducing power is still the main interest in the recent integrated circuit designs. Some of the new low-power design approaches are covered in this talk. Three-dimensional stacking of chips is an effective way to reduce power by decreasing inter-chip communication energy. A low-power yet low-cost interconnection method among stacked chips is wireless communication by L-coupling and C-coupling. The recent advances in these proximity communication approaches are discussed. The other effective approach for achieving low power is to explore operations under ultra-low supply voltage. The effect of variation in the ultra-low operating supply voltage regime is discussed with measurement results. Other point of interest for power-aware systems is the source of energy. The limited access to the power source has been a limiter for the ubiquitous electronics to fly. Wireless transmission of power will offer new application scenes for ubiquitous electronics. The talk also covers an interesting yet exotic integrated circuit made of organic transistors and MEMS switches which acts as a wireless power transmission sheet and may provide a solution to last-meter problem of energy-net.
High performance mobility without agent infrastructure for connection oriented service
Authors: Javed I. Khan, Sandeep Davu, Raid Y. Zaghal
Venue: Pervasive and Mobile Computing (2008)

Currently it is very difficult for connection oriented applications to use a mobile environment. One reason is that Mobile IP requires intermediate software agents to be deployed in the Internet. This infrastructure based mobility scheme offers connectivity to itinerant hosts but incurs significant handoff and tunneling delays along with deployment costs. These delays are particularly harmful for connection oriented applications. In this paper we investigate an alternate mobility scheme which does not require any such infrastructure but only uses an end-point technique and interestingly provides much faster loss-free handoff for connection oriented applications. This End-to-End scheme named Interactive Protocol for Mobile Networks (IPMN) intelligently performs handoff based on information provided by MAC Layer. The network address change is handled by renewing the existing connections by manipulating the TCP/IP stack at the end-points. Also, unlike several other recently proposed end-to-end techniques which require extensive modification of end-protocols, the proposed scheme does not require any functional change in the TCP/IP protocol software. Besides the difference in deployment scenarios, the IPMN offers blazingly fast event based handoff and much faster and simplified transport (no tunneling delay) than MIP. We have implemented IPMN over FreeBSD. In this paper we show the performance advantage of IPMN over MIP with real deployment for three interesting real-time traffic types - www, voice streaming and, steerable/interactive time critical video.
Analysis of k-Neigh Topology Control Protocol for Wireless Networks
Authors: Abbas Nayebi, Hamid Sarbazi-Azad, Kasra Alishahi
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

k-Neigh is a basic neighbor-based topology control protocol based on the construction of k-neighbor graph as logical communication graph. Although k-Neigh is based on a connectivity theory, several topological aspects of the constructed topology are not yet analytically investigated. In this paper, several topological properties of the constructed topology after execution of the protocol, including probability density function of the distance between each node to its ith neighbor, probability of unidirectional links after execution of the first phase of the protocol, average logical degree, and average final transmission range, are investigated analytically. Moreover, an extensive simulation study is performed to validate the analytical results.
GPU Based Acceleration of Telegraph Equation
Authors: Václav imek, Michal Kraus, Jirí Kunovský, Jirí Petrek
Venue: Proceedings of the Tenth International Conference on Computer Modeling and Simulation (2008)

In a matter of just a few years, the programmable graphics processor unit has evolved into an absolute computing workhorse. With multiple cores driven by very high memory bandwidth, today's GPUs offer incredible resources for both graphics and non-graphics processing. An original mathematical method "Modern Taylor Series Method'' (MTSM) which uses the Taylor series method for solving differential equations in a non-traditional way has been developed and implemented in TKSL software. Even though this method is not much preferred in the literature, experimental calculations have shown and theoretical analyses have verified that the accuracy and stability of the Taylor series method exceeds the currently used algorithms for numerically solving differential equations. It is the aim of the paper to illustrate GPU and MTSM for numerical solutions of a telegraph line.
An improved method for steganography on mobile phone
Authors: Mohammad Shirali Shahreza
Venue: Proceedings of the 9th WSEAS International Conference on Systems (2005)

In this paper I introduce an improved method for hiding data in images or steganography. This method is used for secure data transfer from a computer to mobile phones. In this method a message can hide in an image on a PC using a password. The user can download this image from the computer to his mobile phone. The decoder program running on his phone will extract the hidden information by a Java program. The decoder program was installed on a Nokia 6600 mobile phone and tested by posting the students'grades over it.
Geometric discrepancy revisited
Authors: B. Chazelle
Venue: Proceedings of the 1993 IEEE 34th Annual Foundations of Computer Science (1993)

Discrepancy theory addresses the general issue of approximating one measure by another one. Originally an offshoot of diophantine approximation theory, the area has expanded into applied mathematics, and now, computer science. Besides providing the theoretical foundation for sampling, it holds some of the keys to understanding the computational power of randomization. A few applications of discrepancy theory are listed. We give elementary algorithms for estimating the discrepancy between various measures arising in practice. We also present a general technique for proving discrepancy lower bounds.
Autonomous sailboat navigation for short course racing
Authors: Roland Stelzer, Tobias Pröll
Venue: Robotics and Autonomous Systems (2008)

The paper presents a compact method to calculate a suitable route for a sailboat in order to reach any specified target. The calculation is based on the optimisation of the time derivative of the distance between boat and target and features a hysteresis condition, which is of particular importance for beating to windward. The algorithm provides an answer to the perennial question when to tack on upwind courses. Further, it immediately adapts to varying wind conditions. The resulting routes for different conditions are analysed on the basis of a simulation featuring a mathematical boat model. Experiments have been carried out using an unmanned and autonomously controlled sailboat. The navigated route agrees well with the simulation results.
Problem frames and business strategy modelling
Authors: Abdul R. Babar, Didar Zowghi, Karl Cox, Vladimir Tosic, Steven Bleistein, June Verner
Venue: Proceedings of the 3rd international workshop on Applications and advances of problem frames (2008)

Requirements engineering describes how an IT implementation will support business functions. Most IT systems are operational in nature and typical requirements engineering techniques and methods are usually adequate in capturing and documenting the requirements for such systems. Jackson's problem frames is a technique that is suitable for straightforward IT systems descriptions. However, when an organization deploys an IT system that must deliver upon its competitive business strategy, then an appropriate technique or method needs to be used to capture that business strategy in order to connect it to business-critical IT requirements. Here we provide an overview of the use and adaptation of problem frames to connect requirements to business strategy. We found that a simplification of the problem frames notation was necessary and that to be really effective, we had to integrate problem fames with goal modelling and Map, a method that helps describe the evolution of IT over time.
An introduction to problem equivalence with combinatorics
Authors: Manuel Rubio-Sánchez
Venue: ACM SIGCSE Bulletin (2008)

This paper proposes the use of several classes of simple combinatorial problems that share the same solution for teaching problem equivalence and recursion. Our focus is on counting problems that involve Fibonacci numbers. While these problems have simple recursive solutions, we propose that - for teaching purposes - they can also be solved by finding other isomorphic problems for which the solution is known.
Flexible Offline-Visualization for Mobile Wireless Networks
Authors: Johannes Lessmann, Tales Heimfarth
Venue: Proceedings of the Tenth International Conference on Computer Modeling and Simulation (2008)

For the evaluation of wireless network protocols, simulation has established itself as a good compromise between cost and complexity, on the one hand, and accuracy of results, on the other hand. In order to assess and debug the simulated protocols, visualization both in the form of textual console messages and graphical representations can be of great help. In this paper, we present a network visualizer which was written for the wireless network simulator ShoX. Aside from nodes, links, movements and data packets, our visualizer allows to graphically display arbitrary node and link states in an intuitive and flexible way. As opposed to other visualization tools, it provides the possibility to change the way in which such inner states are displayed without running the simulation again. This can significantly improve the designer's productivity especially in complex network scenarios. Further, our visualizer allows to display textual debug messages together with the graphical animation in a synchronized form, thus combining the strengths of textual and graphical informations.
Nonconforming cell boundary element methods for elliptic problems on triangular mesh
Authors: Youngmok Jeon, Eun-Jae Park
Venue: Applied Numerical Mathematics (2008)

The nonconforming cell boundary element (CBE) methods are proposed. The methods are designed in such a way that they enjoy the mass conservation at the element level and the normal component of fluxes at inter-element boundaries are continuous for unstructured triangular meshes. Normal flux continuity and the optimal order error estimates in a broken H^1 norm for the P"1 method are established, which are completion of authors' earlier works [Y. Jeon, D. Sheen, Analysis of a cell boundary element method, Adv. Comput. Math. 22 (3) (2005) 201-222; Y. Jeon, E.-J. Park, D. Sheen, A cell boundary element method for elliptic problems, Numer. Methods Partial Differential Equations 21 (3) (2005) 496-511]. Moreover, two second order methods (the P"2^* and modified P"2^* methods) and a multiscale CBE method are constructed and numerical experiments are performed. Numerical results show feasibility and effectiveness of the CBE methods.
Insulin Producing Cells Derived from Human Marrow Stromal Cells
Authors: Min Zhao, Stephanie A. Amiel, Mohamed Rela, Nigel Heaton, Guo Cai Huang
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 01 (2008)

Background. Pluri-potent bone marrow stromal cells (MSCs) are an excellent cell source for unlimited surrogate insulin-producing cells for the treatment of diabetes. We explored this potential of human MSCs (hMSCs) through a non-viral genetic reprogramming approach. Methods, materials and Results. Two hMSC lines were transfected with IPF1, NeuroD1 and Ngn3, followed by differentiation induction in vitro and transplantation into diabetic mice. Human MSCs expressed insulin in vitro, but were not glucose responsive. Following transplantation, hMSCs differentiated further and >12% grafted cells expressed insulin and seemed to be glucose responsive. Diabetic mice transplanted with manipulated hMSCs showed reduced blood glucose levels (7.63mM). Most mice became normoglycaemic (6.9+/-0.64mM). Conclusions. Our data confirm that hMSCs can be induced to express insulin sufficient to reverse diabetes in a mouse model. Our triple gene approach has created cells that seem less glucose responsive in vitro but which become more efficient after transplantation.
Scratching the surface of advanced topics in software engineering: a workshop module for middle school students
Authors: Paolo A. G. Sivilotti, Stacey A. Laugel
Venue: Proceedings of the 39th SIGCSE technical symposium on Computer science education (2008)

A common approach for introducing computer science to middle school students is to teach them a simple yet engaging programming language A different approach is to teach them some advanced topic independent of any particular language or syntax We describe a 3-hour workshop module designed to do both This module has been piloted with a group of thirty 8th grade girls. It uses the Scratch programming language to develop the advanced software engineering concepts of specifications, refinement, and composition After this module, students were enthusiastic about continuing to program in Scratch independently and also felt they learned something about computer science as a discipline.
Immunity based genetic algorithm for solving quadratic assignment problem (QAP)
Authors: Chou-Yuan Lee, Zne-Jung Lee, Shun-Feng Su
Venue: Proceedings of the 2nd WSEAS International Conference on Electronics, Control and Signal Processing (2003)

In this paper, immunity based genetic algorithm is proposed to solve quadratic assignment problem (QAP). The QAP problem, known as NP-hard problem, is a combinatorial problem found in the optimal assignment of facilities to allocations. The proposed algorithm is to enhance the performance of genetic algorithms by embedded immune systems so as to have locally optimal offspring, and it is successfully applied to solve QAP. From our simulations for those tested problems, the proposed algorithm has the best performances when compared to other existing search algorithms.
IDEA: A New Intrusion Detection Data Source
Authors: William Mahoney, William Sousan
Venue: Proceedings of the 2008 International Conference on Information Security and Assurance (isa 2008) (2008)

In the context of computer systems, an intrusion is generally considered to be a harmful endeavor to prevent others from legitimate use of that system, to obtain data which is not normally available to the intruder, or to plant data or disrupt data already existent on the machines. Traditionally intrusion detection has relied on two data sources: various log files which record user’s activity, and network traffic which contains potential threats. This research presents a system which we call IDEA; the Intrusion DEtection Automata system. We utilize a third source of data for intrusion detection in the form of an instrumented process. Open source software is recompiled using a modified compiler we have created, and the resulting executable program generates the data as it runs. An external monitoring facility then checks the behavior of the program against known good execution paths. These paths are specified either using a domain specific language and hand-written rules, or by running the software in a learning mode and capturing the normal behavior for later comparison.
Grid Computing: Achievements and Prospects, 1 edition
Authors: Sergei Gorlatch, Paraskevi Fragopoulou, Thierry Priol
Venue:  (2008)

Grid Computing: Achievements and Prospects,the 9thedited volume of the CoreGRID series, includes selected papers from the CoreGRID Integration Workshop, held April 2008 in Heraklion-Crete, Greece. This event brings together representatives of the academic and industrial communities performing Grid research in Europe. The workshop was organized in the context of the CoreGRID Network of Excellence in order to provide a forum for the presentation and exchange of views on the latest developments in grid technology research. Grid Computing: Achievements and Prospects is designed for a professional audience, composed of researchers and practitioners in industry. This volume is also suitable for graduate-level students in computer science.
SIA: Secure information aggregation in sensor networks
Authors: Haowen Chan, Adrian Perrig, Bartosz Przydatek, Dawn Song
Venue: Journal of Computer Security (2007)

In sensor networks, data aggregation is a vital primitive enabling efficient data queries. An on-site aggregator device collects data from sensor nodes and produces a condensed summary which is forwarded to the off-site querier, thus reducing the communication cost of the query. Since the aggregator is on-site, it is vulnerable to physical compromise attacks. A compromised aggregator may report false aggregation results. Hence, it is essential that techniques are available to allow the querier to verify the integrity of the result returned by the aggregator node. We propose a novel framework for secure information aggregation in sensor networks. By constructing efficient random sampling mechanisms and interactive proofs, we enable the querier to verify that the answer given by the aggregator is a good approximation of the true value, even when the aggregator and a fraction of the sensor nodes are corrupted. In particular, we present efficient protocols for secure computation of the median and average of the measurements, for the estimation of the network size, for finding the minimum and maximum sensor reading, and for random sampling and leader election. Our protocols require only sublinear communication between the aggregator and the user.
Retrieving similar code fragments based on identifier similarity for defect detection
Authors: Norihiro Yoshida, Takashi Ishio, Makoto Matsushita, Katsuro Inoue
Venue: Proceedings of the 2008 workshop on Defects in large software systems (2008)

Similar source code fragments, known as code clones, may involve similar defects caused by the same mistake. However, code clone detection tools cannot detect certain code fragments (e.g. modified after copy-and-pasted). To support developers who would like to detect such defects, we propose a method to retrieve similar code fragments in source code based on the similarity of identifiers between a query and a target code fragment. We present two case studies of similar defects in open source systems.
Bio-inspired Algorithms for Mobility Management
Authors: Javid Taheri, Albert Y. Zomaya
Venue: Proceedings of the The International Symposium on Parallel Architectures, Algorithms, and Networks (2008)

This work presents a survey on bio-inspired algorithms formerly used to solve the location management problem in two different network schemes: Paging Cell and Location Area. For a better comparison, two test networks, generated by intelligent algorithms to present real world traffics, are used in this work. Several conclusions were made after comparing their answers. The results provide new insight into the mobility management problem that can influence the design of future networks.