Miracle-dz/UniFAR-FTUs huggingface dataset:
Tele-Impedance: Preliminary results on measuring and replicating human arm impedance in tele operated robots

This work introduces the concept of Tele-Impedance as a method for controlling/teleoperating a robotic arm in contact with the environment. Opposite to bilateral force-reflecting teleoperation control approach, which uses a position/velocity command combined with force feedback from the robot side, Tele-Impedance enriches the command sent to the slave robot by combining the position reference with a stiffness (or full impedance) reference. The desired stiffness profile is directly estimated from the arm of the human operating the remote robotic arm. We preliminarily investigate the effectiveness of this method while teleoperating a slave robotic arm to execute simple tasks. The KUKA light weight robotic arm is used as the slave manipulator. The endpoint (wrist) position of the human arm is monitored by an optical tracking system while the stiffness of the human arm is estimated from the electromyography (EMGs) signal measurements of four flexor-extensor muscle pairs, in realtime. The performance of Tele-Impedance control method is assessed by comparing the results obtained while executing a peg-in-hole task, with the slave arm under i) constant low stiffness, ii) constant high stiffness or iii) under Tele-Impedance control. The experimental results demonstrate the effectiveness of the Tele-Impedance control method and highlight its potential use to safely execute tasks with uncertain environment constraints which may result in large deviations from the commanded position trajectories.
Wearable computing and the geographies of urban childhood: working with children to explore the potential of new technology

This paper describes a workshop run as part of 'A New Sense of Place? ' an initiative exploring and developing the interface between children and new mobile 'wearable' ICTs. This initiative is one part of 'Mobile Bristol', a wider project developing wearable devices, their applications and understandings of their potential in social terms. 'A New Sense of Place? ' is particularly interested in considering how these new technologies might integrate with childhood and how they might be applied to help children to reengage with urban spaces. The paper establishes the rationale for this work and describes a two day exploratory workshop with 10 children held in April 2002. The workshop was designed to introduce children to the technology and explore whether, from the children's point of view, the technology might hold enough potential for their use in the urban environment for the work to develop.
Possible earthquake precursors revealed by LF radio signals

Abstract. Among radio signals, low frequency (LF) radio signals lie in the band between 30–300 kHz. Monitoring equipment with the ability to measure the electric strength of such signals at field sites, were designed and assembled in Italy. From 1993 onwards, the electric field strength of the MCO (216 kHz, France) broadcasting station has been collecting measurements at two sites in central Italy that were chosen according to very low noise levels. At the end of 1996, radio signals from the CLT (189 kHz, Italy) and CZE (270 kHz, Czech Republic) broadcasting stations were included in the measurements. Meteorological data from central Italy were also collected over the same time period in order to study the influence of weather conditions on the experimental measurements. During the monitoring period, we observed some evident attenuation of the electric field strength in some of the radio signals at some of the receivers. The duration of the attenuation observed was several days, so it could possibly be related to particular meteorological conditions. On the other hand, this phenomenon might represent precursors of moderate (3.0 M 3.5) earthquakes that occurred near the receivers (within 50 km) along the transmitter-receiver path. In this case, it is possible that the pre-seismic processes could have produced irregularities in the troposphere, such as ducts, reflecting layers and scattering zones, so that some local troposphere defocusing of the radio signals might have occurred. These observations were related only to moderate earthquakes and in these cases, suitable meteorological conditions were probably needed to observe the effect. Between February – March 1998, we observed at one measuring site, a significant increase in the CZE electric field strength. Unfortunately, we could not use the data of the other receiver in this case, due to frequent interruptions in the data set. The increase might have been a precursor of the strong seismic sequence (M = 5.0–6.0) that occurred during March – May 1998 in Slovenia at a location over 400 km from the receiver, but lying in the middle of the transmitter-receiver path. In this case, it is possible that an ionospheric disturbance, produced by the pre-seismic processes, might have occurred.
Stimulating Creative Partnerships in Human-Agent Musical Interaction

Musical duets are a type of creative partnership with a long history of artistic practice. What can they tell us about creative partnerships between a human and a computer? To explore this question, we implemented an activity-based model of duet interaction in software designed to support musical metacreation and investigated the experience of performing with it. The activity-based model allowed for the application of reflexive interactive processes, previously used in dialogic interaction, to a synchronous musical performance context. The experience of improvising with the computational agent was evaluated by expert musicians, who reported that interactions were fun, engaging, and challenging, despite some obvious limitations in the musical sophistication of the software. These findings reinforce the idea that even simple metacreative systems can stimulate creative partnerships and, further, that creative human-machine duet partnerships may well produce, like human-human duet partnerships, more than the sum of their parts.
A Migration Framework for Ubiquitous Computing Applied in Mobile Applications

Ubiquitous computing envisions an environment where physical and digital devices are seamlessly integrated. But migration is one of the critical issues of ubiquitous computing across the different applications because of heterogeneous resources. Hence, mobile applications must adapt to changing contexts and resource availabilities as they migrate from one environment to the next. The most of ubiquitous computing works are concentrating on the mobile infrastructure for wireless networking. This system proposes a migration framework for mobile application based ubiquitous computing as well as it provides for mobility. The main goal of our proposed framework is to enable a seamless user-experience when users move around in a ubiquitous computing environment whether the application is in local or global environment. The contribution of this paper is that ontologies are used in this framework to check how similar between different components are. Another contribution is that we use context information to decide how the best to adapt migrating applications to enable a seamless user experience
Collaborative handover mechanism for real-time services

Next generation networks intend to offer pervasive and ubiquitous services to the customers wherever they are and whatever the application they are using. To achieve this goal, service continuity across homogenous and heterogeneous networks must be guaranteed. Although Fast Mobile IPv6 overcomes the long handover latency of Mobile IPv6 and makes this delay acceptable for real-time applications, the long initiation handover delay represents a constraint for fast-moving mobiles which don't have sufficient time to exchange all the FMIPv6 messages before the connection is broken. In this paper we propose an enhanced FMIPv6 protocol using Media Independent Handover services. MIH supplies FMIPv6 with lower layer indications that allow the mobile to make intelligent and optimized handovers. This scheme increases the probability of FMIPv6 predictive mode by reducing the handover initiation delay. Moreover, by using link event indications the mobile will be served until its physical disconnection, and as soon as it connects to the new network, the packets will be forwarded from the new access router without waiting for attachment announcement from FMIPv6. We show through analytic analysis that our scheme reduces handover delay as well as packet loss in both predictive and reactive handovers. In addition, buffer size needed to buffer packets in access routers during the handover is smaller. Finally, the proposed mechanism avoids excessive ping pong events among wireless networks.
Highly Real, Highly Damped, and Other Asymptotic Quasinormal Modes of Schwarzschild-Anti De Sitter Black Holes

We analyze analytically the asymptotic regions of the quasinormal mode frequency spectra with infinitely large overtone numbers for D-dimensional Schwarzschild black holes in anti de Sitter spacetimes. In this limit, we confirm, using different methods, the analytic results obtained previously in the literature. In addition, we show that in certain spacetime dimensions there exist other regions of the asymptotic quasinormal mode spectrum which have not been explored in the literature. Among these is the highly real region of the quasinormal mode spectrum, where the real part of the frequency approaches infinity while the damping rate approaches a finite value. These modes resemble the normal modes in a pure anti de Sitter space. We show that the damping rate of the highly real quasinormal mode frequencies in four spacetime dimensions is less than the damping rate of the lowest overtone quasinormal mode calculated by other authors. This makes the highly real quasinormal modes the most relevant modes in the context of AdS4/CFT3 correspondence. We also argue that the highly real quasinormal modes can serve as a testing ground for the new interpretation of black hole asymptotic quasinormal modes proposed by Maggiore. We also explore the possible connection between other asymptotic regions of the quasinormal mode spectrum and the quantum level spacing of the horizon area spectrum.
Multi-Instance Multilabel Learning with Weak-Label for Predicting Protein Function in Electricigens

Nature often brings several domains together to form multidomain and multifunctional proteins with a vast number of possibilities. In our previous study, we disclosed that the protein function prediction problem is naturally and inherently Multi-Instance Multilabel (MIML) learning tasks. Automated protein function prediction is typically implemented under the assumption that the functions of labeled proteins are complete; that is, there are no missing labels. In contrast, in practice just a subset of the functions of a protein are known, and whether this protein has other functions is unknown. It is evident that protein function prediction tasks suffer from weak-label problem; thus protein function prediction with incomplete annotation matches well with the MIML with weak-label learning framework. In this paper, we have applied the state-of-the-art MIML with weak-label learning algorithm MIMLwel for predicting protein functions in two typical real-world electricigens organisms which have been widely used in microbial fuel cells (MFCs) researches. Our experimental results validate the effectiveness of MIMLwel algorithm in predicting protein functions with incomplete annotation.
Metric-Preserving Reduction of Earth Mover's Distance

Earth mover's distance (EMD for short) is a perceptually meaningful dissimilarity measure between histograms. The computation of EMD reduces to a network flow optimization problem; however, it lays a heavy computational burden when the number of locations of histograms is large. In this paper, we address an efficient formulation for computing the exact EMD value. We prove that the EMD problem reduces to a problem with half the number of constraints regardless of the ground distance. We then propose a further reduced formula in which the number of variables is reduced from O(m2) to O(m) for histograms with m locations when the ground distance is derived from a graph with a homogeneous neighborhood structure. Specifically, EMD problems with L1, L∞ and D-norm ground distances can be reduced in this manner. Some experiments show that the reduction helps compute the EMD efficiently.
Needs Oriented Framework for Producing Requirements Decision Material - NORM

The need of understanding and supporting requirements engineering decisions in market-driven product development is motivated by the complexity and economical impact of these decisions. While being a key for success, correct and timely decisions are dependent on the availability and the quality of decision material (requirements, business cases, cost-value estimations etc). This paper presents a needs-oriented framework (NORM) for identifying and assuring the creation of appropriate decision material for RE decisions. NORM is based on analysis of the applied RE process and characteristics of separate RE decisions, focusing mainly on pre-project activities. The framework is developed in close cooperation with industry with the intention to ensure that resources are spent on producing just-the-necessary information at the right time and to be able to monitor and control this production effort.
Is the Mandelbrot set computable?

This work is concerned with the question whether the Mandelbrot set is computable. The computability notions that we consider are studied in computable analysis and will be introduced and discussed. We show that the exterior of the Mandelbrot set, the boundary of the Mandelbrot set, and the hyperbolic components satisfy certain natural computability conditions. We conclude that the two‐sided distance function of the Mandelbrot set is computable if the famous hyperbolicity conjecture is true. We also formulate the question whether the distance function of the Mandelbrot set is computable in terms of the escape time. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of 4-DOFs forceps with force sensing using pneumatic servo system

In the teleoperated minimally invasive surgery systems, measurement and display of sense of force to the operator is a problem. In this paper, we proposed a master-slave system for laparoscopic surgery, which can provide force feedback to the surgeon without using force sensors. Pneumatic cylinders were used as the actuator of the manipulators to achieve this. First, we developed two forceps manipulators to construct a master-slave system which have 4-DOFs at the tip. A bilateral dynamic control system was then designed using a neural network for acquisition of the inverse dynamics. The obtained inverse dynamics was used as a feedforward controller and to estimate the external force from the differential pressure of the cylinders. Experimental results showed that the developed system successfully display the contact force on the slave side to the operator on the master side
Discrete‐time analysis of MAP/PH/1 multiclass general preemptive priority queue

We use the matrix‐geometric method to study the MAP/PH/1 general preemptive priority queue with a multiple class of jobs. A procedure for obtaining the block matrices representing the transition matrix P is presented. We show that the special upper triangular structure of the matrix R obtained by Miller [Computation of steady‐state probabilities for M/M/1 priority queues, Oper Res 29(5) (1981), 945–958] can be extended to an upper triangular block structure. Moreover, the subblock matrices of matrix R also have such a structure. With this special structure, we develop a procedure to compute the matrix R. After obtaining the stationary distribution of the system, we study two primary performance indices, namely, the distributions of the number of jobs of each type in the system and their waiting times. Although most of our analysis is carried out for the case of K = 3, the developed approach is general enough to study the other cases (K ≥ 4). © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 662–682, 2003.
Verification and comparison of four numerical schemes for a 1D viscoelastic blood flow model

A reliable and fast numerical scheme is crucial for the 1D simulation of blood flow in compliant vessels. In this paper, a 1D blood flow model is incorporated with a Kelvin–Voigt viscoelastic arterial wall. This leads to a nonlinear hyperbolic–parabolic system, which is then solved with four numerical schemes, namely: MacCormack, Taylor–Galerkin, monotonic upwind scheme for conservation law and local discontinuous Galerkin. The numerical schemes are tested on a single vessel, a simple bifurcation and a network with 55 arteries. The numerical solutions are checked favorably against analytical, semi-analytical solutions or clinical observations. Among the numerical schemes, comparisons are made in four important aspects: accuracy, ability to capture shock-like phenomena, computational speed and implementation complexity. The suitable conditions for the application of each scheme are discussed.
A method for pitch estimation from noisy speech signals based on a pitch-harmonic extraction

A new method for pitch estimation from noisy speech signals based on a pitch-harmonic extraction is presented in this paper. At first, a variable-length average magnitude difference function (VLAMDF) that is able to alleviate the adverse effects of intrinsic falling minima of the conventional AMDF, has been proposed. We argue that the fast Fourier transform (FFT) power spectrum of the VLAMDF is capable of revealing an estimate of a pitch-harmonic (PH) more accurately even in a heavy noisy scenario. Then, exploiting the extracted PH, a two-fold criterion is developed in the FFT domain to acquire the corresponding harmonic number for the determination of the pitch. The superior efficacy of the proposed pitch estimator relative to some of the existing ones is confirmed through simulation results using the Keele database.
High gain MMW hybrid antenna using SIW technology

A high gain microstrip/substrate integrated waveguide (SIW) antenna operates at 30.5 GHz is proposed. Slot feeding mechanism is employed to excite the dominant mode TM010 in a circular patch radiator which is used to feed a surface mounted circular SIW. A gain enhancement of 3.5 dB has been achieved over the single patch antenna. Parametrical studies have been carried out using both Ansoft HFSS and MWS CST simulators to calculate prototype dimensions with improved performance. The optimized design has an operating frequency range from 29.5 GHZ to 32.1 GHz with a bandwidth of 8.6%. The overall antenna realized gain is around 10 dB over the operating band, which makes it suitable for MMW short range communication or MMW imaging applications.
Robot arm pose estimation by pixel-wise regression of joint angles

To achieve accurate vision-based control with a robotic arm, a good hand-eye coordination is required. However, knowing the current configuration of the arm can be very difficult due to noisy readings from joint encoders or an inaccurate hand-eye calibration. We propose an approach for robot arm pose estimation that uses depth images of the arm as input to directly estimate angular joint positions. This is a frame-by-frame method which does not rely on good initialisation of the solution from the previous frames or knowledge from the joint encoders. For estimation, we employ a random regression forest which is trained on synthetically generated data. We compare different training objectives of the forest and also analyse the influence of prior segmentation of the arms on accuracy. We show that this approach improves previous work both in terms of computational complexity and accuracy. Despite being trained on synthetic data only, we demonstrate that the estimation also works on real depth images.
General purpose computing on low-power embedded GPUs: Has it come of age?

In this paper we evaluate the promise held by low-power GPUs for non-graphic workloads that arise in embedded systems. Towards this, we map and implement 5 benchmarks, that find utility in very different application domains, to an embedded GPU. Our results show that apart from accelerated performance, embedded GPUs are promising also because of their energy efficiency which is an important design goal for battery-driven mobile devices. We show that adopting the same optimization strategies as those used for programming high-end GPUs might lead to worse performance on embedded GPUs. This is due to restricted features of embedded GPUs, such as, limited or no user-defined memory, small instruction-set, limited number of registers, among others. We propose techniques to overcome such challenges, e.g., by distributing the workload between GPUs and multi-core CPUs, similar to the spirit of heterogeneous computation.
Nearby Debris Disk Systems with High Fractional Luminosity Reconsidered

By searching the IRAS and ISO databases, we compiled a list of 60 debris disks that exhibit the highest fractional luminosity values (fd > 10-4) in the vicinity of the Sun (d < 120 pc). Eleven out of these 60 systems are new discoveries. Special care was taken to exclude bogus disks from the sample. We computed the fractional luminosity values using available IRAS, ISO, and Spitzer data and analyzed the Galactic space velocities of the objects. The results revealed that stars with disks of high fractional luminosity often belong to young stellar kinematic groups, providing an opportunity to obtain improved age estimates for these systems. We found that practically all disks with fd > 5 × 10-4 are younger than 100 Myr. The distribution of the disks in the fractional luminosity versus age diagram indicates that (1) the number of old systems with high fd is lower than was claimed before, (2) there exist many relatively young disks of moderate fractional luminosity, and (3) comparing the observations with a current theoretical model of debris disk evolution, a general good agreement could be found.
Tag clouds and keyword clouds: evaluating zero-interaction benefits

Tag clouds are typically presented so that users can actively utilize community-generated metadata to query a collection. This research investigates whether such keyword clouds, and other interactive search metadata, also provide measureable passive support for users who do not directly interact with them. If so, then objective interaction-based measurements may not be the best way to evaluate these kinds of search user interface features. This paper discusses our study design, and the insights provided by a pilot study that led to a series of improvements to our study design.
Temperature performance of sub-1V ultra-low power current sources

This paper presents the temperature performance of two self-biased current sources. We have employed a simple topology to design 4 nA and 900 pA current references implemented in both 0.35 mum and 0.18 mum technologies, respectively. Experimental results showed that the current source implemented in 0.35 mum technology can operate at a supply voltage as low as IV and at 650 mV in 0.18 mum CMOS technology. The temperature performance of the current source is analyzed in this paper. The association of a very simple topology, an efficient design procedure, low voltage cascode transistor and low output conductance trapezoidal transistors has resulted in small area, ultra low power consumption and a line regulation better than 0.2%/V of supply voltage.