Miracle-dz/UniFAR-FTUs huggingface dataset:
Low-delay center-bridged and distributed combining schemes for multipoint videoconferencing

Multipoint videoconferencing is a natural evolution of two-point videoconferencing and can increase its value to users. Currently, ITU-T's SG8 and SG15 are working on multipoint control related issues; ANSI's T1A1.5 is also working in this area. The video coding and related communication standards of the upcoming MPEG4 and H.26P will all include multipoint communication capability. This paper investigates transport structures and the associated combining schemes that can be used to support multipoint videoconferencing. Since low delay is a major issue for multipoint interactive communications, a distributed structure which renders the lowest delay with many other system advantages is especially investigated. We first analyze the insertion delay of a QCIF combiner bridge which have been proposing for multipoint videoconferencing. Partial input-output pipelining has been used to reduce the delay. To reduce the insertion delay caused by unevenly distributed inputs, a parallel parsing scheme is proposed. This parallel parsing scheme allows low complexity inputs not to be held up by high complexity inputs and can reduce insertion delay significantly. An efficient delay- reduction algorithm using intraslice coding was also cited in a previous proposal. As a comparison, we describe low delay pel-domain transcoding schemes which have similar delay performance with coded-domain combining but have much higher complexities. We also describe a recent proposal which eliminates most of the insertion delay but which require major changes to existing standards and encoder and decoder implementations. The performance of a distributed transport structure in providing multipoint video services is then investigated. Using the face that bandwidth usage is an important factor in estimating network complexity, it is shown that a distributed transport structure saves 40 to 62.5% bandwidth for a 4-point conferencing and also renders the shortest delay when compared with other center- bridged structures. We then discuss multipoint control and decoder implementations using the distributed transport structure. It is shown that a parallel decoding structure can be used to combine multiple inputs to realize a short delay which is identical to the delay of a two-point conference. The complexity of this special decoder, though, is larger than a regular decoder. A cascaded combiner-decoder at the user site is then shown to make a good compromise between implementation complexity, bandwidth efficiency and delay performance.
Technology-Enhanced Language Learning: Construction of Knowledge and Template-Based Learning in the Foreign Language Classroom

When discussing the current state of the art with regard to the use of new technologies in the foreign language classroom, two issues tend to come up again and again. On the one hand, it cannot be denied that even today, in the so-called post-communicative era, the effects of traditional instructivist theories of language learning with their transmission-based modes of learning are still somewhat dominant, in particular at the grassroots level. This is all the more surprising, as a discussion of constructivism as an appropriate platform for new approaches to language learning and acquisition seems to have dominated the debate at least on a theoretical level in recent years. On the other hand, it is becoming more and more apparent that the available offline and online software tools offer exciting opportunities for the language classroom that cannot be adequately attended to without calling the paradigm of instruction into question. This paper is an attempt to contribute to the ongoing debate on this crucial issue by offering some key principles that move the discussion further in the direction of constructivist learning theories. A few of the theoretical issues discussed in Germany in the context of CALL and TELL are presented. New information and communication technologies will be touched upon, but the main focus will be an assessment of constructivism as the appropriate paradigm for language learning in the new millennium. In addition, the paper considers using Papert's term constructionism as a basis for putting theory into practice and in order to keep separate the theoretical platform of such an approach and its practical implementation in the knowledge society. On a methodological level, construction of knowledge and information processing are regarded as key activities in language learning. In conclusion, template-based learning is discussed as a possible metaphor for the design of technology-enhanced learning materials for the next millennium aimed at providing learners with constructionist learning scenarios.
Technology-Rich Ethnography for Examining the Transition to Authentic Problem-Solving in a High School Computer Programming Class

This study utilized elements of technology-rich ethnography to create a rich description of a multi-user virtual environment in a high school computer programming class. Of particular interest was the transition that took place in classroom culture from one characterized by a well-defined problem solving approach to one more indicative of open learning environment. Using technology, high school students created learning activities and resources for use by younger students in the virtual environment. Evidence supported that high school students initially benefitted from the new open environment; however, some immutable elements of the classroom environment presented barriers to peer collaboration and motivation for high-level, creative work. Our findings lend support to the argument that teachers in high school computer programming classes should incorporate the following features in their curricula: open-ended problem solving, real-world clients, group work, student autonomy and ample opportunities for student creative expression.
Comparison of FBRM® and PIA for investigating the precipitation of Kraft lignin from aqueous solutions: Influence of salt type, concentration, temperature and pH

In this work, precipitation of softwood Kraft lignin was studied. Two methods for measuring the particle size distribution were used and compared to each other. The first method has been successfully used in other studies and is called FBRM® (focused beam reflectance measurement), which is a laser-based light technique. The other is a new optical measuring method referred to as particle size analyzer or PIA. The experimental parameters in this study was temperature, pH, lignin concentration, salt type and concentration. FBRM® measurements were done in situ in order to gain further understanding of the precipitation. The effect of salt addition beyond the amount needed for onset of precipitation has also been studied. The study has been focused on commissioning the PIA-equipment, development of the PIAs experimental method and analysis of its performance. Analyzing the PIA was done by comparing the volume based particle size distribution from it with a calculated volume based particle size distribution from the FBRM® results. The chord length distribution from the FBRM® was extremely consistent in between all the experiments with the only truly deviating result coming from a single experiment. The deviating result came from an experiment at room temperature where the solution underwent gelation. Adding additional salt increased the chord counts but did not change the chord distribution. The PIA’s results were poor and inconsistent to begin with, but semi-decent results were obtained after developing the methodology. The total counts registered by the PIA in a single trial proved to be an indicator of the results. Good results came from total counts above 1 000 000. The PIA’s video display was another useful tool for developing the experimental method. The methodology developed for the PIA worked by initially lowering the lignin concentration. Then the lignin was dosed or sampled in by turning off selected pumps which led to consistent results. Further improvements are still needed if the PIA is to be used in laboratory or industrial settings.
Preserving location privacy for a group of users

Location privacy is an interesting problem that has been receiving considerable attention. This problem has been widely discussed from the individual point of view; however, there exist only a few works that support location privacy for a group of users. In this paper we consider the problem of supporting location privacy for a group of users during the use of location-based services (LBSs). We assume a group of users who want to benet from a LBS and nd the nearest meeting place that minimizes their aggregate distance. Each user in this scenario wants to protect his or her location from the LBS, outside attackers, and other group members. We show that individual solutions for location privacy cannot be directly applied to the group location privacy problem and a special solution must be developed. We identify the privacy issues for this group scenario and propose a resource-aware solution in order to satisfy these group privacy issues. Our solution is based on secure multiparty computation and the anonymous veto network protocol. The proposed protocol decreases the number of group queries to a large extent, as it only sends a single query to the LBS. Consequently, the LBS overhead to evaluate the query and the size of the LBS result are signicantly decreased. The proposed protocol also protects the LBS from the excessive disclosure of points of interest and the LBS provider only needs to apply an existing private nearest neighbor (NN) query algorithm instead of an aggregate NN query algorithm. The performance and security analysis show that the protocol is secure against a partial collusion attack and a denial- of-service attack in a malicious model.
Review of metadata formats

Increasing use of the Internet has heightened awareness among the information community of the need to provide user friendly searching and navigation tools that lead to quality information. An essential part of gaining effective access to Internet resources is to provide an index of available items in order to save users time and network overload. Discussions on metadata are focused on the format of the record used as the basis for the index. Control of the vast number of resources of the Internet requires an appropriate record format (or formats) which will enable the resource to be adequately described and easily located; records must be compatible with an appropriate search engine which in turn would ideally be compatible with a search and retrieval Internet protocol and all components should conform to international standards. At present there are a number of formats which meet at least some of these criteria, each of which has its own strengths.
The Kinematics and Dynamics of the Globular Clusters and Planetary Nebulae of NGC 5128

A new kinematic and dynamic study of the halo of the giant elliptical galaxy NGC 5128 is presented. From a spectroscopically confirmed sample of 340 globular clusters and 780 planetary nebulae, the rotation amplitude, rotation axis, velocity dispersion, and total dynamical mass are determined for the halo of NGC 5128. The globular cluster kinematics were searched for both radial dependence and metallicity dependence by subdividing the globular cluster sample into 158 metal-rich ([Fe/H] > -1.0) and 178 metal-poor ([Fe/H] < -1.0) globular clusters. Our results show that the kinematics of the metal-rich and metal-poor subpopulations are quite similar: over a projected radius of 0-50 kpc, the mean rotation amplitudes are 47 ± 15 and 31 ± 14 km s-1 for the metal-rich and metal-poor populations, respectively. There is a indication within 0-5 kpc that the metal-poor clusters have a lower rotation signal than in the outer regions of the galaxy. The rotation axis shows an interesting twist at 5 kpc, agreeing with the zero-velocity curve presented by Peng and coworkers. Within 5 kpc both metal-rich and metal-poor populations have a rotation axis nearly parallel to the north-south direction, which is 0°, while beyond 5 kpc the rotation axis twists ∼180°. The velocity dispersion displays a steady increase with galactocentric radius for both metallicity populations, with means of 111 ± 6 and 117 ± 6 km s-1 within a projected radius of 15 kpc for the metal-rich and metal-poor populations; however, the outermost regions suffer from low number statistics and spatial biases. The planetary nebula kinematics are slightly different. Out to a projected radius of 90 kpc from the center of NGC 5128, the planetary nebulae have a higher rotation amplitude of 76 ± 6 km s-1 and a rotation axis of 170° ± 5° east of north, with no significant radial deviation in either determined quantity. The velocity dispersion decreases with galactocentric distance. The total mass of NGC 5128 is found using the tracer mass estimator, described by Evans et al., to determine the mass supported by internal random motions and the spherical component of the Jeans equation to determine the mass supported by rotation. We find a total mass of (1.0 ± 0.2) × 1012 M⊙ from the planetary nebula data extending to a projected radius of 90 kpc. The similar kinematics of the metal-rich and metal-poor globular clusters allow us to combine the two subpopulations to determine an independent estimate of the total mass, giving (1.3 ± 0.5) × 1012 M⊙ out to a projected radius of 50 kpc. Lastly, we publish a new and homogeneous catalog of known globular clusters in NGC 5128. This catalog combines all previous definitive cluster identifications from radial velocity studies and HST imaging studies, as well as 80 new globular clusters with radial velocities from a study of M. A. Beasley et al. (in preparation).
Delay‐dependent filtering design for time‐delay systems with Markovian jumping parameters

Two filtering problems—H∞ filtering and H2 filtering—for the linear Markovian jump systems with time delay are considered in this paper. The proposed new filtering approach guarantees that the results are less conservative than that obtained by other existing approaches. Numerical example well demonstrates the proposed algorithms. Copyright © 2006 John Wiley & Sons, Ltd.
A methodology to evaluate the effect of video compression on the performance of analytics systems

The Image Library for Intelligent Detection Systems (i-LIDS) provides benchmark surveillance datasets for analytics systems. This paper proposes a methodology to investigate the effect of compression and frame-rate reduction, and to recommend an appropriate suite of degraded datasets for public release. The library consists of six scenarios, including Sterile Zone (SZ) and Parked Vehicle (PV), which are investigated using two different compression algorithms (H.264 and JPEG) and a number of detection systems. PV has higher spatio-temporal complexity than the SZ. Compression performance is dependent on scene content hence PV will require larger bit-streams in comparison with SZ, for any given distortion rate. The study includes both industry standard algorithms (for transmission) and CCTV recorders (for storage). CCTV recorders generally use proprietary formats, which may significantly affect the visual information. Encoding standards such as H.264 and JPEG use the Discrete Cosine Transform (DCT) technique, which introduces blocking artefacts. The H.264 compression algorithm follows a hybrid predictive coding approach to achieve high compression gains, exploiting both spatial and temporal redundancy. The highly predictive approach of H.264 may introduce more artefacts resulting in a greater effect on the performance of analytics systems than JPEG. The paper describes the two main components of the proposed methodology to measure the effect of degradation on analytics performance. Firstly, the standard tests, using the ‘f-measure’ to evaluate the performance on a range of degraded video sets. Secondly, the characterisation of the datasets, using quantification of scene features, defined using image processing techniques. This characterization permits an analysis of the points of failure introduced by the video degradation.
The Implementation Of An Online Mathematics Placement Exam And Its Effects On Student Success In Precalculus And Calculus

Janet Callahan, Boise State University Janet M. Callahan is Associate Dean for Academic Affairs at the College of Engineering at Boise State University and Professor of Materials Science and Engineering Department. She received her Ph.D. in Materials Science, her M.S. in Metallurgy and her B.S. in Chemical Engineering from the University of Connecticut. Her educational research interests include freshmen engineering programs, math success, K-12 STEM curriculum, and recruitment and retention in engineering and STEM fields.
A control process model of code-switching

Code-switching (CS) is central to many bilingual communities and, though linguistic and sociolinguistic research has characterised different types of code-switches (alternations, insertions, dense CS), the cognitive control processes (CPs) that mediate them are not well understood. A key issue is how during CS speakers produce the right words in the right order. In speech, serial order emerges from a speech plan in which items are represented in parallel. We propose that entry into the mechanism for speech planning (a competitive queuing mechanism) is governed by CPs best suited to the particular types of code-switches. Language task schemas external to the language network govern access. In CS, they are coordinated cooperatively and operate in a coupled or in an open control mode. The former permits alternations and insertions whereas the latter is required for dense CS. We explore predictions of this CP model and its implications for CS research.
The four spaces – a new model for the public library

Purpose – The aim of this paper is to present a model for the public library created by the authors.Design/methodology/approach – The paper is divided into three parts. The first part emphasizes considerations regarding today's focus on both the virtual and the physical library. The second part describes the four‐space model, including examples of libraries as illustrations of the different spaces and examples of how the model is being used in the Nordic library‐world. The third part pinpoints some critical questions in relation to the model.Findings – The paper shows how the four‐space model has been used in different ways in the Nordic countries since it was presented for the first time in a Danish report on public libraries in 2010.Practical implications – The four‐space model can be a useful tool in relation to developing, building, designing, arranging and rearranging public libraries. Furthermore the model can be a tool for management and communication in connection with library plans and policy and.
Accuracy Investigation for Structured-light Based Consumer 3D Sensors

This work focuses on the performance investigation of consumer 3D sensors with respect to their repeatability and accuracy. It explores currently available sensors based on the 3D sensing technology developed by PrimeSense and introduced to the market in the form of the Microsoft Kinect. Accuracy and repeatability can be crucial criteria for the use of these sensors outside their intended use for home entertainment. The test strategies for the study are motivated by the VDI/VDE 2634 guideline. At the core of the work is the investigation of several units of the Asus Xtion Pro and the PrimeSense Developer Kit and a comparison of their performance. Altogether eighteen sensor units were tested. The results of the proposed test scenario for the sensor units show excellent repeatability at a few millimetres. However, absolute accuracy is worse and can be up to a few centimetres. Sensor performance varies greatly both for sensors of the same manufacturer and in-between manufacturers.
Coping with the Challenges of the Digital World: The Experience of Nigerian Female Academic Library and Information Professionals (LIP)

In recent years, library and information services have developed from the traditional print based services to technology driven systems engendered by the adoption of Information and Communication Technology (ICT) in library operations and services. These developments have brought about an increase in the responsibility of Library and Information Professionals (LIP) in academic institutions that are exposed to traditional and ICT driven operations as well as research needed for career progression. Furthermore, in some developing countries like Nigeria, female LIP socio-cultural responsibilities differ from their male counterparts. Hence, female LIPs are faced with issues of: coping with the migration to ICT driven operations and services, career progression requirements, and other socio-cultural expectations. This article seeks to determine the coping strategies of female librarians to the challenges of the digital world. A survey was carried out among all female academic LIPs in southern Nigeria. The questionnaire was designed to elicit information on the benefits as well as challenges emanating from operations/services in the library, career progression and societal expectations, in addition to their coping strategies. The outcome of the research reveals the impact of technological progress on female professionals in developing countries and the steps that could be taken to help overcome these challenges.
Writing in the disciplines: research evidence for specificity

Academic writing, much like any other kind of writing, is only effective when writers use conventions that other members of their community find familiar and convincing. Essentially the process of writing involves creating a text that we assume the reader will recognise and expect, and the process of reading involves drawing on assumptions about what the writer is trying to do. It is this writer-reader coordination which enables the co-construction of coherence from a text. Scholars and students alike must therefore attempt to use conventions that other members of their discipline, whether journal editors and reviewers or subject specialist teachers and examiners, will recognise and accept. Because of this discourse analysis has become a central tool for identifying the specific language features of target groups. In this paper I draw on my own work, conducted over several years into research and student genres, to show how some familiar conventions of academic writing are used in different disciplines and what these differences can tell us about the work in the disciplines themselves.
The view from industry: LIS students on placement

Purpose – This paper aims to report on the outcomes of a survey of organisations in Australia and Slovenia hosting undergraduate Library and Information Studies (LIS) students on professional placement to better understand the reasons behind organisations accepting students, the workload implications and their satisfaction with the process. Design/methodology/approach – Hosting organisations were asked to complete a survey on various aspects of the placement process. Findings – For both countries, hosts reported favourably on their experience, and virtually, all felt that while it was a real commitment of time and resources on their part, it was a responsibility they were happy to take on. There was little difference between the two cohorts, suggesting that the findings from this research may be an accurate picture of the situation for LIS placements hosts more generally. The positive view of the placement and the belief in its role in LIS education is further strengthened by this study. Research limitations/implications – The research suggests that hosting students is not seen as an onerous task, but one which brings benefits to both parties. This will be useful in promoting student placements when looking for new host opportunities. Originality/value – This study has added to the limited literature in the LIS field on the experience of host organisations. Obtaining similar results across two countries added to the reliability of the findings which will help inform those planning future student placements.