Miracle-dz/UniFAR-FTUs huggingface dataset:
Coding for Wireless Broadcast and Network Secrecy

In the first part of this thesis, we exploit wireless broadcast across different layers in wireless networks. The wireless channel is distinguished by its broadcast nature. Wireless broadcast provides a fertile ground to improve the efficiency of existing wireless networks and design new ones. Specifically, we first consider relaying strategies for memoryless two-way relay channels at the physical layer. We generalize networking layer network coding operating on a finite field to physical layer network coding, which is a mapping from the relay's received signal to its transmitted signal. We analyze the symbol-error performance of several relay strategies, and optimize the relay function via functional analysis. Our results indicate that the interference caused by wireless broadcast can be exploited to improve the spectrum efficiency. We then develop a cross-layer framework with wireless broadcast, which integrates rate control, network coding and scheduling in transport, network and link layers. Under the primary interference model, we show that the link scheduling problem is the maximum weighted hypergraph matching problem, which is NP-complete. We propose several distributed approximation algorithms and bound their worst case performance. Next, we describe a new class of medium access control (MAC) protocol, which uses successive interference cancelation to resolve packet collision due to wireless broadcast. Each user is allowed to transmit at different data rates chosen randomly from an appropriately determined set of rates. We characterize the throughput of the proposed protocol compared to that with a centralized controller. A game-theoretic framework along with the dynamic algorithms is proposed to achieve the desired throughput optimal equilibrium, which provides a valuable perspective to understand existing MAC protocols and a general framework to design new ones to improve the system performance. In the second part of this thesis, we consider the problem of secure transmission in the presence of a wiretapper. Due to wireless broadcast, wireless signals are particularly easy to jam and intercept. We derive the secrecy capacity region for the case when the location of the wiretapped links is known and propose several achievable strategies for the case when such information is unknown. We give an example to show that the secrecy capacities of the two cases are generally unequal and show that in both cases computing the secrecy capacity is NP-complete.
Analysis of Parametric Adaptive Signal Detection with Applications to Radars and Hyperspectral Imaging

Abstract : New parametric space-time adaptive processing (STAP) based detectors are introduced and examined. Unlike conventional techniques that estimate the characteristics of the disturbance from only the secondary data, the proposed detectors obtain such knowledge jointly from the primary and secondary data. When the number of pulses within a coherent processing interval is sufficiently large, the proposed detectors can function even without any secondary data, making them strong candidates for detection in non-homogeneous environments. The proposed detectors are investigated by both theoretical analysis and numerical study using simulated and real radar data. Extensive comparison with conventional STAP methods shows that the proposed detectors can better deal with training-limited scenarios while being computationally simpler. The proposed techniques are also extended for target detection in hyperspectral imaging (HSI).
Computer-based fluency training with the terminology of behavior analysis

This study examined the effects of computer-based fluency training on the learning of behavior-analysis terminology. Sixty-nine undergraduates studied the definitions of half a set of behavior-analysis terms using a computer program Think Fast (Parsons, 1989), and half using their regular methods. Think Fast training items consisted of typing the words missing from definitions. On seven out of nine post-training quizzes, students were better able to define terms previously studied with the computer program. In a related experiment, volunteers studied half a new set of terms using the computer, either typing or saying the answers. Students mastered the definitions better when they typed the answers. There were no differences in the presentation order of the concepts so neither a primacy nor a recency effect was supported. Even though the amount of time allowed to study the definitions was the same for both methods, Think Fast training with the typing mode was still superior. This suggests that in both experiments, the superiority of typing the answers using Think Fast was a result of the training method used and not the amount of time devoted to practice with the definitions. Fluency training using Think Fast with the typing mode helps students achieve competency with behavior-analysis terminology.
Differential chaos shift keying : A robust coding for chaotic communication

The statistical attributes of the received chaotic signal are evaluated in the noncoherent chaos shift keying (CSK) modulation scheme in order to perform the demodulation. This approach offers a very simple circuit configuration, but like the other solutions proposed before, it is sensitive to the channel noise and imperfections. In the differential chaos shift keying (DCSK) approach every incoming information bit is encoded into two bits. The first signal serves as a reference, while the second one carries the information. If the binary information to be transmitted is ”1” then first the reference signal is transmitted and after it that signal is repeated. For a ”0”, the inverted version of the reference signal is transmitted. The receiver has a storage capability and the demodulation is performed by evaluating the cross-correlation of the two signals. The effect of noise is reduced by averaging and proper design of the channel filter. The effect of channel imperfections is also reduced, because both the signal and its reference are sent via the same channel. The DCSK approach offers a very robust solution for the chaos communication and it can be implemented with very simple circuitry even in the microwave frequency region.
Consciousness - Raising Tasks Versus Deductive Approach Two Form Focused Instruction Types in Teaching Grammar to Iranian High School EFL Learners

Consciousness-raising (CR) task is a new way of teaching grammar developed in communicative contexts although little has been written on the effectiveness of CR tasks in EFL setting. The present study is an attempt to investigate the impact of CR tasks in Iranian EFL setting by comparing them with deductive, grammar lessons common in the Iranian schools. The subjects of this study were 80 EFL pre-university male students who were randomly assigned to an experimental group and a control one. The control group received three ordinary teacher-fronted, deductive lessons, a common way of teaching methodology in Iran, on three grammatical structures (adverb placement, indirect object placement and the use of relative clause). The experimental group, however, was treated with three ‘consciousness-raising’ (CR) tasks dealing with the same target structures. The results showed that in the short-run, CR tasks were as effective as deductive approach in promoting the learners’ grammatical knowledge while in the long-run, the CR group maintained their gains more effectively than the deductive group. The conclusion is that CR tasks can function more effectively than deductive approach if the following conditions are met: (a) performing the consciousness-raising tasks in learners’ L1; (b) providing the learners with feedback whenever they encounter a problem in solving the tasks; (c) grouping the learners in such a way that at least one learner in each group would be more proficient than the other members to help the less proficient ones understand and discover the rules more effectively.
The Lustre Storage Architecture

This lengthy document often referred to as the "Lustre Book", contains a detailed outline of Lustre file system architecture, as it was created between 2001 and 2005, in accordance with the requirements from various users. Now, in 2019, most features have been implemented, but some only recently, and some along different lines of thought.
Applying Cognitive Linguistics to Learning the Semantics of English to, for and at: an Experimental Investigation

Recent years have witnessed growing interest in cognitive linguistics (CL) and its potential insights for L2 learning. However, few experimental investigations have applied a CL perspective to instructed L2 learning. English prepositions represent a promising target for the application of CL to instructed L2 learning since, contrary to traditional approaches, CL represents the many meanings associated with a single preposition as being systematically related in principled ways. This article lays out the fundamentals of a CL analysis of the semantics of English prepositions and reports on a quasi-experimental study examining the efficacy of applying a CL approach to instructed L2 learning of the semantics of English to, for and at. Comparison of preand post-test results show significant gain scores (p >.0003), indicating that the group of 14 advanced learners who received instruction based on a CL perspective experienced substantial improvement in their understanding of the semantics of the three prepositions.
What does mathematics understanding look like

The concept of mathematical understanding is central to curriculum development, classroom interaction, and the training of mathematics teachers In this paper, some models of the growth of understanding that the literature presents are outlined Some results of a study that documented four primary teachers’ mental models of, and beliefs about, different forms of understanding are reported It is proposed that linear models may restrict ways that these teachers plan lessons Questions for further research are raised
Presteren op vreemde bodem. Een onderzoek naar sociale hulpbronnen en de leeromgeving als studiesuccesfactoren voor niet-westerse allochtone studenten in het Nederlandse hoger onderwijs (1997-2010)

In dit proefschrift is studiesucces van niet-westerse allochtone studenten bestudeerd vanuit verschillende invalshoeken. Analyses van landelijke administratieve bestanden (CBS en IBG) tonen dat de etnische diversiteit van de studentenpopulatie in Nederland sterk is toegenomen in de periode 1997/98-2009/10. Niet-westerse allochtone studenten boeken minder studiesucces dan autochtone studenten: zij vallen vaker uit en behalen lagere rendementen. Achterstanden worden nauwelijks ingelopen. Niet-westerse allochtone groepen verschillen wat betreft studiesucces ook van elkaar. De resultaten kunnen deels worden toegeschreven aan een groter aandeel ‘risico’-studenten binnen niet-westerse allochtone groepen (studenten die met vertraging het hoger onderwijs binnenkomen; (in het hbo) studenten die omzwaaien). Maar ook na het constant houden van (risico-)kenmerken hebben autochtonen een grotere kans op het behalen van studiesucces dan niet-westerse allochtonen. Uit het kwalitatieve onderzoeksmateriaal blijkt het belang van sociaal kapitaal bij een vergelijking tussen blijvers en uitvallers van niet-westerse herkomst. Blijvers beschikken vaker dan uitvallers over een netwerk van sociale hulpbronnen tijdens het studiekeuze- en het studieproces ((school)vrienden, schooldecanen, ouders, overige familie, studiegenoten, docenten, studentbegeleiders). In de leeromgeving speelt de eigen etnische herkomst geen rol voor autochtone informanten, maar wel voor niet-westerse allochtone informanten: regelmatig worden zij in hun contacten met studiegenoten, docenten en studentbegeleiders van (vooral) autochtone afkomst geconfronteerd met hun ‘anders-zijn’. Het studiesucces van autochtone en niet-westerse allochtone studenten blijkt meer gelijk binnen leeromgevingen die via sterke sturing van studenten bij aanvang, een kleinschalige opzet en een betrokken houding van docenten en studentbegeleiders alle studenten de gelegenheid bieden om sociaal kapitaal op te bouwen en in te zetten.
Characterization of Contention in Real Relational Databases

Concurrency control is essential to the correct functioning of a database due to the need for correct, reproducible results. For this reason, and because concurrency control is a well formulated problem, there has developed an enormous body of literature studying the performance of concurrency control algorithms. Most of this literature uses either analytic modeling or random number driven simulation, and explicitly or implicitly makes certain assumptions about the behavior of transactions and the patterns by which they set and unset locks. Because of the di culty of collecting suitable measurements, there have been only a few studies which use trace driven simulation, and still less study directed toward the characterizion of concurrency control behavior of real workloads. In this report, we present a study of three database workloads, all taken from IBM DB2 relational database systems running commercial applications in a production environment. This study considers topics such as frequency of locking and unlocking, deadlock and blocking, duration of locks, types of locks, correlations between applications of lock types, two-phase vs. non-twophase locking, when locks are held and released, etc. In each case, we evaluate the behavior of the workload relative to the assumptions commonly made in the research literature, and discuss the extent to which those assumptions may or may not lead to erroneous conclusions. We also present a simple mathematical model which predicts the frequency of blocking to be expected in these workloads, and compare those predictions to the observed frequency. This document is available as Technical Report No. UCB/CSD 94/801 from Computer Science Division (EECS), 571 Evans Hall, University of California, Berkeley, CA 94720. The authors' research is supported or has been supported in part by the National Science Foundation under grants MIP9116578 and CCR-9117028, by NASA under Grant NCC 2-550, by the State of California under the MICRO program, and by the International Business Machines Corporation, Digital Equipment Corporation, Philips Laboratories/Signetics, Apple Computer Corporation, Mitsubishi Corporation, Sun Microsystems and Intel Corporation.
An integrated approach for searching and browsing in heterogeneous peer-to-peer networks

Peer-to-peer networks have recently gained importance as environments for digital libraries. In this paper, we propose a serviceoriented architecture for supporting two important access modes, searching and browsing, in a hierarchical network. Service-oriented architectures allow for loosely-coupled systems, and the combination of multiple services enables integration of the two paradigms. The services have been designed for optimised reusability and extensibility. E.g., distributed searching and browsing both use the same statistical metadata, and thus the same storage service, for solving their tasks. Browsing services provide an overview over the available content, and interactive exploration of relevant portions of the data space. Resource selection services improve the efficiency of the search process by cost-optimised query routing, and schema mapping services facilitate the integration of data from heterogeneous schemas into one distributed digital library.
Golgi cell mediated inhibition in the cerebellar granule cell layer

The cerebellar cortex integrates multimodal information from mossy fibre (MF) and climbing fibre inputs to perform a variety of computations relating to movement, motor learning and balance. Before MF information can be combined with climbing fibre input in Purkinje cells (PCs) it must pass through the granule cell (GrC) layer wherein it is transformed by the anatomical connectivity and local inhibitory circuit. GrCs receive both tonic and phasic inhibition, the latter arising from the release of gamma aminobutyric acid (GABA) from Golgi cell (GoC) axons. However, the properties of GoC mediated inhibition and its computational significance are not well understood. I have characterised the GoC–GrC synaptic connection using paired whole-cell patch-clamp recordings. My results show that unitary GoC inputs are smaller than previously realised and are frequently mediated purely by spillover from synapses onto adjacent GrCs. I have used the dynamic clamp method to investigate how changes in the frequency and synchrony of spiking in the GoC network can affect GrC computation. I found that changes in GoC firing rate strongly modulate the gain of the GrC input–output (I–O) function, while GoC synchrony can create permissive and non-permissive windows resulting in a patternation of GrC firing that may convey a temporal signal to downstream PCs. GoCs are subject to regulation through the activation of metabotropic glutamate receptors (mGluRs) and nicotinic acetylcholine receptors (nAChRs). I have investigated how these modulatory inputs to GoCs might affect their inhibitory output and show that mGluR activation dramatically reduces GABA release while nAChR activation dramatically increases GABA release from GoCs. My results show that GoCs can exert potent inhibitory control over GrCs that could be relevant to the processing of both temporally coded and rate coded information.
The effect of inquiry-based, hands-on math instruction utilized in combination with web-based, computer-assisted math instruction on 4th-grade students' outcomes

THE EFFECT OF INQUIRY-BASED, HANDS-ON MATH INSTRUCTION UTILIZED IN COMBINATION WITH WEB-BASED, COMPUTER-ASSISTED MATH INSTRUCTION ON 4TH-GRADE STUDENTS' OUTCOMES Jason D. Plourde University of Nebraska Advisor: Dr. John W. Hill Results indicated that 4th-grade students (n = 19) participating in the inquiry-based, hands-on math instruction used in combination with web-based, computerassisted math instruction group and 4th-grade students {n = 19) participating in the inquiry-based, hands-on math instruction alone group did not significantly improve their pretest-posttest Problem Solving/Data Analysis, Concepts/Estimation, Math Total, and Math Computation normreferenced normal curve equivalent achievement test score results. However, 4th-grade students participating in the inquiry-based, hands-on math instruction alone group posttest-posttest scores were statistically significantly greater than students who participated in the combination instruction group across all four subtests. Moreover, all posttest norm-referenced, Normal Curve Equivalent subtest scores for both groups were measured within the average range. On the criterion-referenced math test score
How instructor-developed screencasts benefit college students' learning of maths: insights from an Irish case study.

This qualitative case study explored how students learning Maths at an Irishinstitute of higher education benefited from their instructor’s use of selfdevelopedscreencasts. The screencasts (47 in total) were posted on theinstitute’s Maths Moodle site for students to access. One hundred and thirty-eight(n = 138) students participated in an online open-response survey. Students’commentary was analyzed using thematic content analysis (TCA). Themes thatrepresented different types of screencast benefit to students were generatedfrom the data. Consistent with previous studies, the findings show that a vastmajority of students (88.4%) used the screencasts for many different purposes andviewed the videos as an extremely useful tool that enhanced their Maths learningexperience. Ten primary benefits of screencasts emerged, namely allowingflexible and personalized learning, supplementing lectures and enhancingunderstanding of Maths keyskills, facilitating exam revision and material review,providing multimodal support for Maths learning, helping students to keep trackwith the Maths modules, providing a tighter match with course content, deliveringa vicarious learning experience, serving as a memory aid, filling in gaps in classnotes, and making Maths more enjoyable. The findings support the use ofscreencasts in facilitating and enhancing students’ learning of Maths in highereducation.
Will To Appear

This paper presents an opportunity for the uncertainty that has plagued the novel's criticism to appear as absences in the body of historical knowledge, particularly regarding the notion of life after death. Taking appearance (eg. proof of existence), as opposed to disappearance, as a universally accepted value allows this analysis to interrogate the novel's logic in relation to a variety of conventional systems whose very existence depends on the reproduction of their systems. The ineffectuality of Foucauldian disciplinary institutions in the novel establishes the threat of nonexistence. A significant relationship to Dante's Inferno is rendered, lending the appearance of language an 'enchanted' value through allusions to Dante's intentional invocation of Augustinian corporeal vision. The novel's metalanguage appears enchanted by the body of historical knowledge, particularly as the product of capitalism, discipline and Judeo-Christianity, and programmed by literary precursors William S. Burroughs, Gertrude Stein and Ernest Hemingway. Foregrounded by this complex network, an analysis of the novel’s first chapter demonstrates how an attention to appearance brings the language to life and draws the narrator, equally invested in appearance, into its realm of representation.
The Effect of Word Processing on Writing Achievement.

A study investigated the effect of word processing on the quality of children's writing. Subjects were 32 fifth-graders in a public school in the suburban town of Livingston, New Jersey. One sample had access to computers in their classroom everyday for writing. The other sample group used computers once a week in the lab; their daily writing instruments were a piece of paper and a pencil. Writing samples were taken as a pretest and posttest and scored holistically. Findings supported the hypothesis that there would be no significant difference in the achievement between the samples of students' writing. It should be noted, however, that the difference in the mean scores approached significance. The implication may be that if this study had been conducted over a longer period of time, the experimental sample that used computers may have shown more significant gains over the control group. This study, along with others previously conducted on this subject, does not provide statistical evidence for the advantage of writing on a computer over traditional methods. Nonetheless, as tecanology becomes an integral part of their personal, educational and business lives, students must be prepared for computer litelacy. (Contains 2 tables of data, 25 references, and related research.) (TB) *********************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. ***********************************************************************