Miracle-dz/UniFAR-FTUs huggingface dataset:
Towards reliable communication in low-power wireless body area networks

There is a growing belief that wearable computers and sensors will enable new applications in areas such as healthcare, personal fitness or augmented reality. The devices are attached to a person and connected through a Wireless Body Area Network (WBAN), which replaces the wires of traditional monitoring systems by wireless communication. This comes, however, at the cost of turning a reliable communication channel into an unreliable one. The wireless channel is typically a rather unstable medium for communication and the conditions under which WBANs have to operate are particularly harsh: not only is the channel strongly influenced by the movements of the person, but WBANs also often operate in unlicensed frequency bands and may therefore be exposed to a significant amount of interference from other wireless devices. Yet, many envisioned WBAN applications require reliable data transmission. The goals of this thesis are twofold: first, we aim at establishing a better understanding of how the specific WBAN operating conditions, such as node placement on the human body surface and user mobility, impact intra-WBAN communication. We show that during periodic activities like walking the received signal strength on an on-body communication link fluctuates strongly, but signal strength peaks often follow a regular pattern. Furthermore, we find that in comparison to the effects of fading 2.4 GHz Radio Frequency (RF) interference causes relatively little packet loss — however, urban 2.4 GHz RF noise is bursty (correlated in time), which may be problematic for applications with low latency bounds. The second goal of this thesis is to analyze how communication reliability in WBANs can be improved without sacrificing a significant amount of additional energy. To this end, we first explore the trade-off between communication latency and communication reliability. This analysis is based on a novel packet scheduling algorithm, which makes use of an accelerometer to couple WBAN communication with the movement patterns of the user. The analysis shows that unreliable links can often be made reliable if packets are transmitted at predicted signal strength peaks. In addition, we analyze to what extent two mechanisms can improve robustness against 2.4 GHz RF interference when adopted in a WBAN context: we analyze the benefits of channel hopping, and we examine how the packet retransmission process can be made more efficient by using a novel packet combining algorithm that allows to repair packets corrupted by RF interference. One of the conclusions is that while frequency agility may decrease “burstiness” of errors the static selection of a channel at the upper end of the 2.4 GHz band often already represents a good remedy against RF interference.
High-performance 802.11a wireless LAN via carrier-interferometry orthogonal frequency division multiplexing at 5 GHz

WLAN (wireless local area networks) have emerged as a powerful architecture capable of meeting the needs of next generation broadband wireless communications. The IEEE 802.11a 5 GHz WLAN standard employs OFDM in its physical layer. This paper demonstrates that small changes in this OFDM scheme lead to notable improvements in probability of error performances. Calling the modified WLAN system carrier-interferometry WLAN (or CI-WLAN), we show that in office buildings, at a bit error rate of 10/sup -3/, CI-WLAN offers a 3 dB performance gain over the 802.11a 5 GHz WLAN.
Delta-Polygon Autotransformer Based 24-Pulse Rectifier for Switching Mode Power Supply

In medium and high power capacity switching mode power supply (SMPS), power quality at the AC side is often severely distorted. In this paper, a small magnetic rating delta-polygon autotransformer based 24-pulse rectifier feeding SMPS is designed, constructed, and simulated for harmonic mitigation. Various auto-wound transformers for the 24-pulse AC-DC converter are discussed and compared in terms of magnetic rating and power quality indices, in order that the optimal autotransformer structure can be chosen. The effect of load variation on the proposed 24-pulse rectifier is also analyzed. Moreover, performance of the 6-, 12-, and 18-pulse rectifiers based on delta-polygon autotransformer are studied through comparison. Results demonstrate that the total harmonic distortion of utility current is lower than 6.10% and unity power factor is achieved under varying load.
An integrated approach to the teaching of operations management in a business school

ABSTRACT The authors discuss a curriculum integration effort that a school of business piloted recently. This effort was aimed at integrating the core functions (finance, marketing, management, and operations) so that undergraduate students would better appreciate the full impact of functional decisions on each other and in achieving the corporation's business objectives. The authors deployed a webbed integration model in which a business case was used to highlight the impact of a functional decision on the other three functions. The focus of the article is on how this model was implemented in the context of a required introductory course in operations management. The authors also discuss the results of this effort, lessons learned, and the path forward.
Automatic path control based on integrated steering and external yaw-moment control

Nowadays improving safety is an indispensable part of research issues in the automotive industry. Due to increased travelling time, accident potentials and also traffic congestions, automated vehicles are seen as a way to increase freeway capacity and vehicle speed while reducing accidents resulted from human errors. In order to guide a vehicle automatically, vehicle lateral motion should be controlled, active steering control (ASC) and direct yaw-moment control (DYC) are two common methods to control the vehicle lateral dynamic, automatically. For higher vehicle lateral acceleration, where the tyres will not be capable of producing enough lateral forces (yaw-moment), ASC could not be useful. In such situation, the advantages of DYC can be clearly observed. Indent In this paper, a novel optimal control law is proposed to control the vehicle path, automatically. The control law uses the vehicle dynamic variables such as the yaw and lateral velocities, lateral offset, and the heading error as well as the road-related variables. These are the road curvature and the lateral offset between the desired path and the vehicle as the feedback/feed-forward signals to produce both the front steering angle and the external yaw-moment signals as the control efforts. Simulation results illustrate the dominant power of the front steering/DYC in the control of the vehicle lateral motion.
Standardization of JPEG quantization table for medical ultrasonic echo images

Storing digital medical images is standardized by the DICOM report. Lossy pulse-echo ultrasonic image compression by a JPEG baseline system is permitted by it. The purpose of this paper is to reduce the data volume and to achieve a low bit rate in the digital representation of pulse-echo ultrasonic images without perceived loss of image quality. In image compression with a JPEG baseline system, it is possible to control the compression ratio and image quality by controlling quantization values. This paper attempts standardizing JPEG quantization table for medical ultrasonic echo images by a statistical method. Results reveal that the proposed method achieves a lower bit rate compared with the JPEG standard under the same image quality.
Soft Rhizomes 2.0: A Softvideography Essay

Abstract Softvideo is a term applied by the author to video works which treat the computer as the means of production, distribution and consumption of video works. In these contexts video develops novel affordances or possibilities that problematize traditional uses and understandings of video as time based media. In this essay, which consists of a printed essay and an accompanying interactive academic QuickTime project, a critical and reflective analysis of a series of softvideo templates – the “rhizome templates” – is undertaken. These templates are publicly available and allow video bloggers and others to experiment with softvideo forms. The essay documents the use of the templates and situates them within a critical view of traditional video practice from the point of view of softvideo and video editing as a rhizomatic practice.
Review of PSTD methods for transient electromagnetics

In this paper we review the recent development in pseudospectral time‐domain (PSTD) methods for broadband electromagnetics. Starting from the basic ideas for high‐order approximation of spatial derivatives in periodic and non‐periodic domains, we will discuss the pseudospectral time‐domain methods for Maxwell's equations. Furthermore, some recent time integration schemes for the PSTD methods will be also presented. We will demonstrate these efficient methods with some new results for large scale problems. Copyright © 2004 John Wiley & Sons, Ltd.
Bluetooth-based mobile ad hoc networks: opportunities and challenges for a telecommunications operator

We present results of our initial investigations on Bluetooth-based mobile ad hoc networks (MAN). By building a simple demonstrator of a Bluetooth-based MAN, we find that current implementations of the Bluetooth stack have many shortcomings limiting the practical use of MANs. In particular, protocols for setting up the MAN and establishing routing paths for data packets should be tightly integrated with the lower layers of the stack. Once these issues are solved however, Bluetooth-based MANs may prove a very powerful concept for enabling cheap peer-to-peer communications.
Control Strategies for Flexible Joint Manipulators

Lightweight space robotic systems are known to exhibit elastic effects in their gearboxes, which contribute greatly to the motion of their end-effector. When accurate end-effector positioning is required, such flexible joint vibrations must be taken into account in both the modeling and control of space manipulators. This paper presents an analysis and a comparative numerical simulation study of previous studies on advanced control schemes for flexible joint robots. More specifically, a linear PD control, a rigid-based indirect adaptive control, an indirect adaptive composite control, a nonlinear backstepping control, a transpose Jacobian composite control, and a direct adaptive composite control methodologies are considered. The performance of the controllers is illustrated in a 12.6 × 12.6 m square trajectory tracking scenario by a two-link flexible joint space manipulator.
Neural Network Based Partial Parallel Interference Cancellation Multiuser Detection Using Hebb Learning Rule

- In CDMA communication systems, in order to decrease the influence on reception performance resulted from incorrect decision of the interference users’ information bits in parallel interference cancellation (PIC) process, a recurrent neural network based on Hebb learning rule is designed and applied to adjusting interference cancellation factors (ICF) in partial parallel interference cancellation (PPIC) multiuser detection. Simulatio Hebb-PPIC detection has strong anti improved on the basis of conventional PIC in both conditions of ideal power control and “near scenario.
Telescopic Units: Increasing The Average Throughput Pipelined Designs By Adaptive Latency Control

This paper presents a technique, alternative to performance-drivensynthesis, that allows to drastically increase the averagethroughput of combinational logic blocks by transforming fixed-latencyunits into variable-latency ones that run with a fasterclock cycle.The transformation is fully automatic and can beused in conjunction with traditional design techniques, such aspipelining, to improve the overall performance of speed-criticalsystems.Results, obtained on a large set of benchmark circuits,are very promising.
The structure of tail-biting trellises: minimality and basic principles

Basic structural properties of tail-biting trellises are investigated. We start with rigorous definitions of various types of minimality for such trellises. We then show that biproper tail-biting trellises are not necessarily minimal, even though every minimal tail-biting trellis is biproper. We introduce the notion of linear trellises and prove, by example, that a minimal tail-biting trellis need not have any linearity properties whatsoever. We prove that a trellis is linear if and only if it factors into a product of elementary trellises. Using this result, we show how to construct, for any given linear code C, a tail-biting trellis that minimizes the product of state-space sizes among all possible linear tail-biting trellises. We also prove that every minimal linear tail-biting trellis for C arises from a certain n /spl times/ n characteristic matrix, and show how to compute this matrix in time O(n/sup 2/) from any basis for C.
Improvements in the voice quality of DECtalk/spl reg/

The new version of DECtalk/spl reg/ offers significant improvements in the voice quality of formant-based synthesized voices. The key to the improved voice quality is the incorporation of the HLsyn model; HLsyn is a hybrid articulatory-acoustic model of speech production. The new DECtalk voices sound more natural and can be easily modified to create a variety of different voices. The voices can be tailored to meet the requirements of specific applications and of individual users. The new DECtalk voices are simply better.
LISA-machine description language for cycle-accurate models of programmable DSP architectures

This paper presents the machine description language LISA for the generation of bit- and cycle-accurate models of DSP processors. Based on a behavioral operation description, the architectural details and pipeline operations of modern DSP processors can be covered. Beyond the behavioral model, LISA descriptions include other architecture-related information like the instruction set. The information provided by LISA models enables automatic generation of simulators and assemblers which are essential elements of DSP software development environments. In order to proof the applicability of our approach, a realized model of the Texas Instruments TMS320C6201 DSP is presented and derived LISA code examples are given.
Control of a camera for active vision: foveated vision, smooth tracking and saccade

In an active vision system, the information available for feedback has to be computed from images acquired on real-time. This image processing task can be seen as a degree of freedom that the designer has at hand to maximize the tracking performance, for instance one can define a region of the image where heavy processing is performed - the fovea. Based on control considerations, this paper shows how to compute the optimal size of this fovea, and presents a two-tracking mechanism which is necessary if foveated vision is to be implemented on a real environment.
Efficient 3D elastic full-waveform inversion using wavefield reconstruction methods

ABSTRACTIn reverse time migration (RTM) or full-waveform inversion (FWI), forward and reverse time propagating wavefields are crosscorrelated in time to form either the image condition in RTM or the misfit gradient in FWI. The crosscorrelation condition requires both fields to be available at the same time instants. For large-scale 3D problems, it is not possible, in practice, to store snapshots of the wavefields during forward modeling due to extreme storage requirements. We have developed an approximate wavefield reconstruction method that uses particle velocity field recordings on the boundaries to reconstruct the forward wavefields during the computation of the reverse time wavefields. The method is computationally effective and requires less storage than similar methods. We have compared the reconstruction method to a boundary reconstruction method that uses particle velocity and stress fields at the boundaries and to the optimal checkpointing method. We have tested the methods on a 2D vertical trans.
An approach to biped robot with parallel mechanism

Describes a 3D biped robot where each leg is composed of a 6 DOF parallel mechanism. The proposed mechanism is suited to walking, and the total weight of each leg is expected to be lighter than a serial linked biped robot. This is one of the remarkable features of the proposed mechanism. One side leg consists of three linked arms. Each arm has two active and four passive joints, and is placed in the same direction. There are two kinds of arms where positions of the active joints are different. Thus, the robot can move without interference of each arm. In the paper, theoretical analysis of the biped robot motion with parallel mechanism is shown. Furthermore a 3D dynamic simulator is developed to implement several simulations. To confirm the feasibility of the proposed mechanism, the walking motion is tested by the developed simulator.
A novel algorithm for sensorless motion control of flexible structures

This article demonstrates the validity of using an actuator as a single platform for measurements during a motion control assignment of flexible systems kept free from any kind of measurement. System acceleration level dynamics, parameters and interaction forces with the environment are coupled in an incident reaction torque that naturally rises when a flexible system is subjected to an action imposed by an attached actuator to the system. This work attempts to decouple each of the system parameters out of the incident coupled reaction torque at the interface point of the actuator with the flexible system by way of measurements taken from the actuator, not from the system. The identified parameters, along with the estimated states, are used to achieve sensorless motion control for flexible systems.
Switched-capacitor simulation models for full-chip verification

A description is given of models and techniques used in a switched-capacitor functional model generator. The proposed method is useful for achieving functional verification of chips consisting of clock generating circuitry, switched-capacitor circuits, and other analog or digital blocks. A program, MODGENSC, has been developed which generates the model directly from the circuit description in SWITCAP. With this capability, full-chip mixed digital/analog simulation is achievable and also the simulation time is reduced significantly
Design and Modeling of an Asynchronous Checkpointing System

: As the capability and component count of high performance computing systems increase, the mean time before failure correspondingly decreases. Typically, applications tolerate failures with checkpoint / restart, where an application writes its state in checkpoints on the parallel ﬁle system (PFS); upon failure the application restarts from the last checkpointed state. While simple, this approach su ﬀ ers from high overhead due to contention for PFS resources. A promising solution to this problem is multi-level checkpointing. However, while multi-level checkpointing is successful on today’s machines, it is not expected to be su ﬃ cient for exa-scale class machines, where the total memory sizes and failure rates are predicted to be orders of magnitude higher. Our solution to this problem is a system that combines the beneﬁts of asynchronous and multi-level checkpointing. In this paper, we present the design of our system and a model describing its performance. Our experiments show that our system can improve e ﬃ ciency by 1.1 to 2.0 (cid:2) on future machines. Additionally, applications using our checkpointing system can achieve high e ﬃ ciency even when using a PFS with lower bandwidth.
A Q-factor enhancement technique for MMIC inductors

An increase of 50% in the peak Q-factor and a wider operating bandwidth for monolithic inductors is achieved by exciting a microstrip structure differentially. Conventional excitation of a 8 nH spiral inductor fabricated in a production silicon IC technology resulted in a peak (measured) Q-factor of 6.6 at 1.6 GHz, while the differential connection showed a maximum Q-factor of 9.7 at 2.5 GHz. These experimental results compared favorably with the behaviour predicted from simulation.
Words, Numbers, and Visual Heuristics in Web Surveys: Is There a Hierarchy of Importance?

Respondents follow simple heuristics in interpreting the visual features of questions. The authors carried out two experiments in two panels to investigate how the effect of visual heuristics affects the answers to survey questions. In the first experiment, the authors varied the distance between scale points in a 5-point scale to investigate whether respondents use the conceptual or visual midpoint of a scale. In the second experiment, the authors used different end point labels of a 5-point scale, by adding different shadings of color and numbers that differed both in sign and value (2 to -2), to study whether options that are similar of appearance are considered conceptually closer than when they are dissimilar in appearance. The authors predicted that there is a hierarchy of features that respondents attend to, with verbal labels taking precedence over numerical labels, and numerical labels taking precedence over visual cues. The results confirmed the hypothesis: the effect of spacing of response options and different end points was only apparent in polar point scales and not in fully labeled scales. In addition, this study on two panels, with one consisting of extremely trained respondents and the other of relatively fresh respondents, shows that trained respondents are affected by the distance between response options whereas relatively new respondents are not. To reduce the effect of visual cues, taking into account the robustness of results, the authors suggest it is better to use fully labeled 5-point scales in survey questions.
A fast state reduction algorithm for incompletely specified finite state machines

This paper proposes a state reduction algorithm for incompletely specified FSMs. The algorithm is based on iterative improvements. When the number of compatibles is likely to be too large to handle explicitly, they are represented by a BDD. Experimental results are given to demonstrate that the algorithm described here is faster and obtains better solutions than conventional methods.
Multi Directional Geographical Traceback with n Directions Generalization

Problem Statement: Denial of Service/Distributed Denial of Service (DoS/DDoS) attacks deny regular, internet services from being accessed by legitimate users, either by blocking the services completely, or by disturbing it completely, so as to cause customer baulking. Approach: Several traceback schemes were available to mitigate these attacks. Directional geographical traceback8 (DGT8), directional geographical trackback scheme, with 8 directions was one of them. Having a limited set of 8 directions, DGT8 may not work for routers with more than 8 interfaces. In this study, we had proposed Multi-DGT (DGT-16), a 16 directional geographical traceback scheme having all the advantages of DGT. The 16 directions, though not having exactly equal interface, had nearly equal measures and were identified using a novel scheme of Segment Direction Ratios (SDR). Results: The scheme of DGT16 SDR in directions D1-D16 in quadrant I-IV and DGT32 SDR in directions D1-D9 in quadrant I were examined. Conclusion: The implementation of DGT16, when a packet arrives at the victim, the geographical location of the attack router can be obtained from the data in the SDR subfields, regardless of the source IP address which may be incorrect or compromised.
A new registration algorithm for of ASAS multi-angle images

A new area-based image registration scheme is proposed in this paper for of ASAS 0/spl deg/ and 30/spl deg/ images. It includes a series preprocessings and a resolution hierarchical relational algorithm, and a fast algorithm is used for pixel matching in every layer. The new method is not the same as the feature-based one the authors used in ASAS 0/spl deg/ and 15/spl deg/ image registration, and makes it possible to improve the accuracy of big angle image registration without losing the speed. <<ETX>>