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With the increased use of Internet and information technology all over the world, there is an increased amount of criminal activities that involve computing and digital data. These digital crimes (e-crimes) impose new challenges on prevention, detection, investigation, and prosecution of the corresponding offences. Computer forensics (also known as cyberforensics) is an emerging research area that applies computer investigation and analysis techniques to help detection of these crimes and gathering of digital evidence suitable for presentation in courts. This new area combines the knowledge of information technology, forensics science, and law and gives rise to a number of interesting and challenging problems related to computer security and cryptography that are yet to be solved. In this paper, we present and discuss some of these problems together with two successful cases of computer forensics technology developed in Hong Kong that enable the law enforcement departments to detect and investigate digital crimes more efficiently and effectively. We believe that computer forensics research is an important area in applying security and computer knowledge to build a better society. [ABSTRACT FROM AUTHOR]

This paper is concerned with a multi-resolution tool for analysis of a time series aiming to detect abnormalities in various frequency regions. The task is treated as a kernel based novelty detection applied to a multi-level time series representation obtained from the discrete wavelet transform. Having a priori knowledge that the abnormalities manifest themselves in several frequency regions, a committee of detectors utilizing data dependent aggregation weights is build by combining outputs of detectors operating in those regions. [ABSTRACT FROM AUTHOR]

Amongst several fundamental aspects in multi-agent systems design, the definition of the agent interaction space is of the utmost importance. The specification of the agent interaction has several facets: syntax, semantics, and compliance verification. In an open society, heterogenous agents can participate without showing any credentials. Accessing their internals or their knowledge bases is typically impossible, thus it is impossible to prove a priori that agents will indeed behave according to the society rules. Within the SOCS (Societies Of ComputeeS) project, a language based on abductive semantics has been proposed as a mean to define interactions in open societies. The proposed language allows the designer to define open, extensible and not over-constrained protocols. Beside the definition language, a software tool has been developed with the purpose of verifying at execution time if the agents behave correctly with respect to the defined protocols. This paper provides a tutorial overview of the theory and of the tools the SOCS project provided to design, define and test agent interaction protocols. [ABSTRACT FROM AUTHOR]

This paper is based on the tutorial given as part of the tutorial programme of CLIMA-VI. The tutorial aimed at giving an overview of the various features available in Jason, a multi-agent systems development platform that is based on an interpreter for an extended version of AgentSpeak. The BDI architecture is the best known and most studied architecture for cognitive agents, and AgentSpeak is an elegant, logic-based programming language inspired by the BDI architecture. [ABSTRACT FROM AUTHOR]

One of the simplest protocols for clock synchronization in wireless ad hoc and sensor networks is the converge-to-max protocol, which has the simple logic of adjusting each node's clock to be at least as large as any neighbor's. This paper examines the converge-to-max protocol, showing it to be stabilizing even when node clocks have skew, bounded domains, and dynamic communication links. [ABSTRACT FROM AUTHOR]

All papers have been typed and translated trying to reproduce as much as possible their original aspect. We only used common fonts and the same style for the titles, the abstracts and the bibliography. [ABSTRACT FROM AUTHOR]

Privacy-preserving classification mining is one of the fast-growing sub-areas of data mining. How to perturb original data and then build a decision tree based on perturbed data is the key research challenge. By applying transition probability matrix this paper proposes a novel privacy-preserving classification mining algorithm which suits all data types, arbitrary probability distribution of original data, and perturbing all attributes (including label attribute). Experimental results demonstrate that decision tree built using this algorithm on perturbed data has comparable classifying accuracy to decision tree built using un-privacy-preserving algorithm on original data. [ABSTRACT FROM AUTHOR]

In this paper, an improvement to TCP-Peach+, called TCP-Peach++, is proposed to improve the throughput performance for satellite IP networks with asymmetrical bandwidth and persistent fades. The delayed SACK scheme is adopted to address the problems due to bandwidth asymmetrical satellite links. A new protocol procedure, Hold State, is developed to address the link outages due to persistent fades. The simulation results show that TCP-Peach++ improves the throughput performance during rain fades and addresses the bandwidth asymmetry problems in Satellite IP Networks. [ABSTRACT FROM AUTHOR]

Recently, the request for multimedia broadband services via satellite has been rapidly increasing. We envisage a group of terminals that have to transmit (uplink) to a Network Control Center (NCC) via a geostationary bent-pipe satellite; the NCC is interconnected to the Internet through a router. Terminals employ the DVB-RCS standard to communicate with the NCC. Due to both the intrinsic propagation delay and the presence of a lossy radio channel, the Transport Control Protocol (TCP) is particularly inefficient in the satellite scenario. Therefore, we propose a novel cross-layer mechanism where resources are allocated by the Medium Access Control (MAC) layer at the NCC depending on the TCP behavior at remote terminals. Moreover, the MAC layer can also intervene on the TPC data injection rate to avoid system congestion. Simulation results show that: (i) our scheme prevents the occurrence of TCP timeouts (due to the satellite network congestion), thus improving the utilization of radio resources; (ii) it reduces the mean file transfer time for ftp applications with respect to a classical allocation scheme. This paper has been carried out within A&TCP research group of the "SatNEx" NoE project (URL: www.satnex.org; contract No. 507052) belonging to the 6-th framework of the European Commission. Index Terms:Satellite Networks, DVB-RCS, TCP. [ABSTRACT FROM AUTHOR]

Given the fact that more than half of the world lacks a wired network infrastructure, satellite networks are seen as an important alternative to achieve global coverage. Since most of the world population lives around the equator or in middle-latitude regions, satellite constellations have to deal with different communication requirements from different regions. The traffic requirements become further unbalanced as the population density varies among urban and rural areas. This results in the congestion of some satellites while others remain underused. The issue of traffic engineering over satellite networks can be resolved by distributing the traffic in a balanced way over underutilized links. This paper proposes an Explicit Load Balancing (ELB) routing protocol which is based on information of traffic load at the next hop on the remainder of the path to the destination. A satellite with high traffic load sends signals to its neighboring satellites requesting them to decrease their sending rates before it gets congested and packets are ultimately dropped. Neighboring satellites should accordingly respond and search for other alternate paths that do not include the satellite in question. The performance of the proposed scheme is evaluated through simulations. From the simulation results, the proposed scheme achieves a more balanced distribution of traffic load, and reduces the number of packet drops and queuing delays. The resulting satellite constellation is a better-utilized and traffic-balanced network. [ABSTRACT FROM AUTHOR]

We developed AirTransNote, a computer-mediated classroom collaboration system. The system enables real-time note-sharing. AirTransNote manages notes written by students on paper and enables the teacher to browse through the notes or show them to the students. AirTransNote can analyze students' answers, helping the teacher better understand their problems. The system is not meant to provide an alternative to the conventional way of instruction; rather, it is designed to enhance class interaction. We conducted a preliminary study using questionnaires and found that this system can be feasible to apply for classroom environment. [ABSTRACT FROM AUTHOR]

Many documents exist in both paper and electronic forms. Paper has many well-known advantages, but electronic texts often contain useful information that is not easily accessible from printed paper versions. SGML texts, in particular, are rich sources of additional information. The Active Alice project shows how a reader can use a paper document to access information from its corresponding electronic version without having to manipulate the electronic version via a separate computer interface. The project makes use of a DigitalDesk. This is an ordinary desk augmented with a video camera and computer-driven projector. The camera captures images of the pages on the desk and detects simple user actions such as pointing to specific words on a page. The images are used to associate the pages with their SGML counterparts. Information from the SGML versions can then be conveyed directly to the reader via information projected onto the page or onto other areas of the desk. The project takes its name from the example text used—a version of Alice's Adventures in Wonderland. [ABSTRACT FROM AUTHOR]

High contents of fillers such as kaolin or calcium carbonate limit the use of waste paper, especially in tissue paper production. In order to determine the effect of flotation reagents on the removal of fillers, adsorption, zeta potential, and particle size measurement,s as well as flotation experiments using model dispersions of calcium carbonate, kaolin, and cellulose fibers were carried out. The adsorption of the cationic polymer starts at low initial concentrations on the negatively charged filler surfaces and cellulose fibers. However, due to the steeper slope of the adsorption isotherm on the fillers, the polymer is preferentially adsorbed on the fillers. Furthermore, the adsorption of the polymer causes an increase in the particle size of the fillers. Anionic surfactants are generally better suited for waste paper systems containing calcium carbonate than for those with kaolin. This is due to the fact that the adsorption onto calcium carbonate occurs at lower concentrations than that onto kaolin. Calcium ions dissolved in the pulp improve the adsorption of anionic surfactant onto kaolin and are necessary for a sufficiently high recovery of the fillers. [ABSTRACT FROM AUTHOR]

This paper presents the experimental aspects of a robotic system used for detection, sorting and grading of paper objects from visual features. The experimental system is used as an automated paper recycling system. The system uses simplified stereo vision to compute position estimate of unknown objects. A vector of geometrical and textural features is used for sorting the paper, according to its grade. The grading process uses additional contact sensors for refining grading from visual features. Supervised learning is used for training the decision system to separate paper from other objects. The experimental aspects of the training process are presented in detail. A special vacuum gripper was designed for gripping paper objects detected by the vision system. The experimental results prove the efficiency of the proposed techniques. [ABSTRACT FROM AUTHOR]

In this paper, we present a study of a novel problem, i.e. topic-based citation recommendation, which involves recommending papers to be referred to. Traditionally, this problem is usually treated as an engineering issue and dealt with using heuristics. This paper gives a formalization of topic-based citation recommendation and proposes a discriminative approach to this problem. Specifically, it proposes a two-layer Restricted Boltzmann Machine model, called RBM-CS, which can discover topic distributions of paper content and citation relationship simultaneously. Experimental results demonstrate that RBM-CS can significantly outperform baseline methods for citation recommendation. [ABSTRACT FROM AUTHOR]

Many methodologies appeared in the latest years to deal with multi-agent systems complexity and special development requirements. Each methodology focuses in certain aspects of multi-agent systems development and use different case studies to prove their effectiveness. In order to compare their characteristics it is necessary to use a single case study that requires a complex and distributed solution. This paper presents the development of a very well-known multi-agent systems case study – the Conference Management System – with the Multi-agent Systems Unified Process (MASUP). [ABSTRACT FROM AUTHOR]

This paper presents a digital signal processing tool developed using MatlabTM, which provides a very low-cost and effective strategy for analog-to-digital conversion of legated paper biomedical maps without requiring dedicated hardware. This software-based approach is particularly helpful for digitalizing biomedical signals acquired from analogical devices equipped with a plottingter. Albeit signals used in biomedical diagnosis are the primary concern, this imaging processing tool is suitable to modernize facilities in a non-expensive way. Legated paper ECG and EEG charts can be fast and efficiently digitalized in order to be added in existing up-to-date medical data banks, improving the follow-up of patients. [ABSTRACT FROM AUTHOR]

We study the problem of predicting the popularity of items in a dynamic environment in which authors post continuously new items and provide feedback on existing items. This problem can be applied to predict popularity of blog posts, rank photographs in a photo-sharing system, or predict the citations of a scientific article using author information and monitoring the items of interest for a short period of time after their creation. As a case study, we show how to estimate the number of citations for an academic paper using information about past articles written by the same author(s) of the paper. If we use only the citation information over a short period of time, we obtain a predicted value that has a correlation of r = 0.57 with the actual value. This is our baseline prediction. Our best-performing system can improve that prediction by adding features extracted from the past publishing history of its authors, increasing the correlation between the actual and the predicted values to r = 0.81. [ABSTRACT FROM AUTHOR]

This paper describes an approach to the use of citation links to improve the scientific paper classification performance. In this approach, we develop two refinement functions, a linear label refinement (LLR) and a probabilistic label refinement (PLR), to model the citation link structures of the scientific papers for refining the class labels of the documents obtained by the content-based Naive Bayes classification method. The approach with the two new refinement models is examined and compared with the content-based Naive Bayes method on a standard paper classification data set with increasing training set sizes. The results suggest that both refinement models can significantly improve the system performance over the content-based method for all the training set sizes and that PLR is better than LLR when the training examples are sufficient. [ABSTRACT FROM AUTHOR]

We present a framework for generating paper-cutting effects on mesh models. Our system involves the construction of model defined paper-cutting patterns, extraction of the medial axis (MA) from the mesh models and position location for patterns on the mesh surface based on MA. Patch sets for placing patterns on the mesh surface are determined by the region growing algorithm. After patch sets parameterization, patterns are drawn on the parameterized domain and mapped onto the mesh surface by inverse sampling. [ABSTRACT FROM AUTHOR]

Since its discovery in 1981, human immunodeficiency virus type 1 (HIV-1) has rapidly emerged as one of the most devastating infectious pathogens of this century (1-3). The World Health Organization (WHO) estimates that, as of 1995, there were at least 15 million HIV- infected men, women, and children worldwide, with the vast majority of infections occurring in developing countries and isolated rural regions where specimen collection, preparation and shipment are difficult (4). Simple and improved sampling methods that can be widely applied under difficult field conditions are needed to effectively monitor the changing dynamics of the HIV-1/AIDS pandemic, track the spread of HIV-1 variants among different population groups, and ensure that research and interventive activities are directed against biologically important variants of the virus. To date, at least eight major HIV-1 subtypes, designated A through H, have been identified (5,6). More recently, a ninth subtype, I, has been detected (7), as well as several highly divergent, or "outlying" variants of HIV-1 that have been tentatively classified as group O (8,9). This subtyping is based on a relatively small number of specimens collected from a few geographic areas and the full range and distribution of HIV-1 variants remains to be established. The collection of whole blood on filter paper provides an innovative and powerful approach for the systematic and unbiased collection of large numbers of field specimens for diagnostic and surveillance purposes (10-19). [ABSTRACT FROM AUTHOR]

This paper focuses on the precise recommendation of scientific papers in academic networks where users' social structure, items' content and attributes exist and have to be profoundly exploited. Different from conventional collaborative filtering cases with only a user-item utility matrix, we study the standard latent factor model and extend it to a heterogeneous one, which models the interaction of different kinds of information. This latent model is called ˵Content + Attributes″, which incorporates latent topics and descriptive attributes using probabilistic matrix factorization and topic modeling to figure out the final recommendation results in heterogeneous scenarios. Moreover, we further propose a solution to handle the cold start problem of new users by adopting social structures. We conduct extensive experiments on the DBLP dataset and the experimental results show that our proposed model outperforms the baseline methods. [ABSTRACT FROM AUTHOR]

Biotechnology for Solving Slime Problems in the Pulp and Paper Industry includes the following topics: biofilms, glycocalyx; microbial extracellular polysaccharides; organisms within the slime; slime control, biocides, cleaning; surface-active agents in slime control, synthetic surfactants, biosurfactants, alternative biocide-free growth control methods, enzymatic slime deposit control, bacteriophages, introduction of competing micro-organisms; biological equilibrium; and biodispersants. [ABSTRACT FROM AUTHOR]

Pitch problems in pulp mills are often caused by the resinous materials (pitch) in wood which comprise approximately 2-8% of total composition depending upon the species and time of year. Traditional methods to control pitch problems include natural seasoning of wood before pulping and/or adsorption and dispersion of the pitch particles with chemicals in the pulping and papermaking processes, accomplished by adding fine talc, dispersants and other kinds of chemicals. Within the last five years, two new and different methods of combatting pitch, both of which are biotechnological in basis, have been developed independently and are now used industrially. Hata and colleagues of Nippon Paper Industries developed a pitch control method using the enzyme lipase, which catalyzes the hydrolysis of triglycerides. Farrell and colleagues of Sandoz Chemicals Biotech (now known as Clariant) developed a method of pitch control and biocontrol using a fungus developed in the laboratory from the same type of organisms which cause natural aging, the Ascomycetes. This fungus is non-colored and prevents the staining and decrease of brightness normally associated with aged wood. [ABSTRACT FROM AUTHOR]

Electrophoresis and chromatography on paper have proved extremely useful techniques for the separation of small peptides prior to amino acid sequencing. Polarity determines the rate of migration of a peptide during chromatography, whereas both charge and size are the main determinants during electrophoresis. The two techniques therefore are complimentary, and when used in conjunction can resolve most peptide mixtures into their pure components. [ABSTRACT FROM AUTHOR]