Miracle-dz/UniFAR-FTUs huggingface dataset:
Semiorthogonal decompositions of derived categories of equivariant coherent sheaves

Let be an algebraic variety with an action of an algebraic group . Suppose that has a full exceptional collection of sheaves and these sheaves are invariant under the action of the group. We construct a semiorthogonal decomposition of the bounded derived category of -equivariant coherent sheaves on into components that are equivalent to the derived categories of twisted representations of . If the group is finite or reductive over an algebraically closed field of characteristic 0, this gives a full exceptional collection in the derived equivariant category. We apply our results to particular varieties such as projective spaces, quadrics, Grassmannians and del Pezzo surfaces.
Evolving turbulence and magnetic fields in galaxy clusters

We discuss, using simple analytical models and magnetohydrodynamic (MHD) simulations, the origin and parameters of turbulence and magnetic fields in galaxy clusters. Any pre-existing tangled magnetic field must decay in a few hundred million years by generating gas motions even if the electric conductivity of the intracluster gas is high. We argue that turbulent motions can be maintained in the intracluster gas and its dynamo action can prevent such a decay and amplify a random seed magnetic field by a net factor of typically 104 in 5 Gyr. Three physically distinct regimes can be identified in the evolution of turbulence and magnetic field in galaxy clusters. First, the fluctuation dynamo will produce microgauss (μG)-strong, random magnetic fields during the epoch of cluster formation and major mergers. At this stage pervasive turbulent flows with rms velocity of about 300 km s -1 can be maintained at scales of 100-200 kpc. The magnetic field is intermittent, has a smaller scale of 20-30 kpc and average strength of 2 μG. Secondly, turbulence will decay after the end of the major merger epoch; we discuss the dynamics of the decaying turbulence and the behaviour of magnetic field in it. Magnetic field and turbulent speed undergo a power-law decay, decreasing by a factor of 2 during this stage, whereas their scales increase by about the same factor. Thirdly, smaller-mass subclusters and cluster galaxies will produce turbulent wakes where magnetic fields will be generated as well. Although the wakes plausibly occupy only a small fraction of the cluster volume, we show that their area-covering factor can be close to unity, and thus they can produce some of the signatures of turbulence along virtually all lines of sight. The latter could potentially allow one to reconcile the possibility of turbulence with ordered filamentary gas structures, as in the Perseus cluster. The turbulent speeds and magnetic fields in the wakes are estimated to be of the order of 300 km s -1 and 2 μG, respectively, whereas the turbulent scales are of the order of 200 kpc for wakes behind subclusters of a mass 3 x 10 13 M ⊙ and about 10 kpc in the galactic wakes. Magnetic field in the wakes is intermittent and has the scale of about 30 and 1 kpc in the subcluster and galactic wakes, respectively. Random Faraday rotation measure is estimated to be typically 100-200 rad m -2 , in agreement with observations. We predict detectable polarization of synchrotron emission from cluster radio haloes at wavelengths 3-6 cm, if observed at sufficiently high resolution.
A Study on Water-line Performance Improvement based on OFDM System for Underwater Communication

To overcome the poor communication environment between the underwater acoustic signal transmitter and receiver, previous research applied underwater acoustic OFDM communication system which had efficient bandwidth capacity and could mitigate multi-path delay spread effect via guard interval. Concurrently with this OFDM signal, additional data could be transmitted through spread spreading technique, which was called water-line technique. However, this decreased the performance of the OFDM modulation because the water-line signal degraded OFDM signal. In this paper, we studied the efficient method to minimize signal interference by water-line signal so that we applied convolution error correction code on water-line to minimize signal level.
Modeling ELF radio atmospheric propagation and extracting lightning currents from ELF observations

Observations of extremely low frequency (ELF) radio atmospherics (sferics), the transient electromagnetic fields radiated by lightning discharges, are used to determine the current moment waveforms of vertical lightning discharges. In order to extract this information the propagation of radio atmospherics from source to receiver must be modeled accurately, especially in view of the important role played by the D and E regions of the ionosphere at these long (> 200 km) wavelengths. We model broadband ELF sferic waveforms by adapting a single‐frequency ELF propagation code to calculate an ELF propagation impulse response under the assumption of horizontal ionospheric homogeneity, with which we extract the source lightning current waveform from an observed ELF sferic waveform using a deconvolution method based on linear regularization. Tests on modeled sferics indicate that the method is accurate and relatively insensitive to noise, and we demonstrate the application of the technique with a sprite‐associated sferic. Since ELF sferics can often be observed many thousands of kilometers from the source discharge, the technique developed here represents a powerful new method of remotely sensing lightning current waveforms.
Telemanipulation enhancement through user's motion intention recognition and fixture assistance

In telemanipulation systems, assistance of virtual fixture can improve manipulation capability and dexterity. This assistance provides aids not only for path following, but also for reaching target and avoiding obstacles. Conventionally, these assistances are based on the environment information, without knowing user's motion intention. In this paper, user's motion intention is combined with real-time environment information for applying appropriate assistance. If the current task is following a path, a hard virtual fixture orthogonal to the path is applied. Or if the task is to position a target, an attractive force filed is produced. In order to successfully recognize user's motion intention, a hidden Markov model (HMM) is developed to classify human actions, such as following path, positioning target and avoiding obstacles. The algorithm is tested on the simulation platform.
The Colliding Plane Wave and Energy-Momentum Problems in General Relativity and Teleparallel Gravity

This paper has been removed by arXiv administrators because it plagiarizes gr-qc/0603075, 0706.3245, gr-qc/0403097, gr-qc/0404108, gr-qc/0303034, hep-th/0206052, and others. This paper has excessive overlap with the following papers also written by the authors or their collaborators: 0704.0525 and others.
How One Microtask Affects Another

Microtask platforms are becoming commonplace tools for performing human research, producing gold-standard data, and annotating large datasets. These platforms connect requesters (researchers or companies) with large populations (crowds) of workers, who perform small tasks, typically taking less than five minutes each. A topic of ongoing research concerns the design of tasks that elicit high quality annotations. Here we identify a seemingly banal feature of nearly all crowdsourcing workflows that profoundly impacts workers' responses. Microtask assignments typically consist of a sequence of tasks sharing a common format (e.g., circle galaxies in an image). Using image-labeling, a canonical microtask format, we show that earlier tasks can have a strong influence on responses to later tasks, shifting the distribution of future responses by 30-50% (total variational distance). Specifically, prior tasks influence the content that workers focus on, as well as the richness and specialization of responses. We call this phenomenon intertask effects. We compare intertask effects to framing, effected by stating the requester's research interest, and find that intertask effects are on par or stronger. If uncontrolled, intertask effects could be a source of systematic bias, but our results suggest that, with appropriate task design, they might be leveraged to hone worker focus and acuity, helping to elicit reproducible, expert-level judgments. Intertask effects are a crucial aspect of human computation that should be considered in the design of any crowdsourced study.
A New Method of Image Compression Based on Quantum Neural Network

In this paper we combine with quantum neural networks and image compression using Quantum Gates as the basic unit of quantum computing neuron model, and establish a three layer Quantum Back Propagation Network model, then the model is used for realizing image compression and reconstruction. Since the initial weights of neural networks were slow convergence, we use Genetic Algorithm (GA) to optimize the neural network weights, and present a mechanism called clamping to improve the genetic algorithm. Finally, we combined the Genetic Algorithm with quantum neural networks to finish image compression. Through an experiment we can see the superiority of the improved algorithm.
Ant Colony System Algorithm for Real-Time Globally Optimal Path Planning of Mobile Robots

Abstract A novel method for the real-time globally optimal path planning of mobile robots is proposed based on the ant colony system (ACS) algorithm. This method includes three steps: the first step is utilizing the MAKLINK graph theory to establish the free space model of the mobile robot, the second step is utilizing the Dijkstra algorithm to find a sub-optimal collision-free path, and the third step is utilizing the ACS algorithm to optimize the location of the sub-optimal path so as to generate the globally optimal path. The result of computer simulation experiment shows that the proposed method is effective and can be used in the real-time path planning of mobile robots. It has been verified that the proposed method has better performance in convergence speed, solution variation, dynamic convergence behavior, and computational efficiency than the path planning method based on the genetic algorithm with elitist model.
Understanding the prospect of success in professional training: an ethnography into the assessment of problem-based learning

ABSTRACT One of the most fundamental innovations in higher education is the introduction of the method known as problem-based learning (PBL). While literature has largely focused on its learning goals and the transition from lectures to tutorials, little research has problematised why this is a successful methodology and what we consider as students’ success. Drawing upon various ethnographic techniques, the authors analyse PBL as a field of expectations in light of Expectation-Value Theory. Beyond merely showing that PBL is a culturally constructed practice, the article elaborates on how students’ expectations inform practices, performance and evaluation, which is important for assessing the successfulness of the method. By discussing students’ expectations, dynamics and power relations, the present article is a contribution to the research addressing what has come to be known as the ‘black box’ of PBL.
Multimodal speech synthesis

Multimodal speech synthesis ("talking heads") encompasses synthesis of speech from text ("text-to-speech", TTS) plus synthesis of a visual presentation of a face that is lip-synced to the generated audio ("visual TTS", VTTS). Talking heads are now practical because of the ever-increasing computing power and falling prices of computer hardware. This paper highlights recent technological breakthroughs relevant to the two modalities. In addition, it exposes synergies between the audio and visual technology components. Finally, the paper summarizes test results that highlight the impact of multimodal speech synthesis in communications and e-commerce applications.
A Novel Approach for Spatially Correlated Multi-User MIMO Channel Modeling : Impact of Surface Roughness and Directional Scattering

Recent multiple-input-multiple-output (MIMO) research has moved from independent fading channels to correlated fading channels that better fit real wireless environments. For point-to-point MIMO, many spatially correlated statistical or experimental channel models have been presented in the literature. However, correlated multi-user MIMO channels have not yet been studied, which is critical for investigating the wireless network capacity. Moreover, all previous physical ray tracing approaches assume omni-directional scatterers. However, in real environments, scatterers are not necessarily omni-directional. In this paper, a novel approach for modeling multi-user MIMO channels is proposed. The technique is applicable (in our first attempt) to the non-line-of-sight (NLOS) situation. It considers the impact of scatterers roughness which leads to the directionality in propagation. The directionality of the scatterers is described by the Helmholtz-Kirchihoff field integral and random rough surface theory. In urban street environments, the closed form expression of intra-user (point-to-point MIMO) and inter-user (multi-user MIMO) correlation of any pairwise channel gains is derived. Moreover, the coherence region (where inter-user correlation is expected to be high) is quantitatively presented. It is observed that the coherence region tends to be small for smaller roughness, i.e., higher directionality of the scatterers. This result would help to build realistic fading models for the capacity studies in multiuser MIMO systems.
Men as Victims of Domestic Violence some issues to consider

This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission. Requests and inquiries concerning reproduction and rights should be directed to DVIRC. In Australia, the phrase 'domestic violence' is preferred to its equivalent American term, 'battering'. Similarly, Australians are more familiar with describing the person who commits the violence as the 'perpetrator', rather than the 'batterer' or the 'battering partner'; and the person offended against as the 'vic-tim' rather than, say, the 'battered wife'. However some Australian critics prefer terms like 'men who use violence', and many feminists dislike the term 'victim', which they see as dis-empowering and objectifying. In this Discussion Paper, unless discussing US research and theory, I use the term 'perpetrator' or phrases like 'behaved violently'. 'Victim' and 'survivor' are used interchangeably, and sometimes together, to refer to people who are experiencing or have suffered domestic violence. This is in order to convey the sense that domestic violence is a process of victimisation, but that people can also survive it and move on with their lives. The term 'family violence' originated as a concept and approach in the early 1970s in the US In that country, in contrast to the largely feminist-originated concepts of 'domestic violence' or 'wife battering', the stance on 'family violence' (sometimes more recently described as 'intimate violence in families', e.g. Gelles 1997) regards gender as one variable among many, and often refers to 'spousal violence'. Family violence work focuses on violence as a broader problem that happens among many family members and within broader society, and includes child abuse and corporal punishment. American family violence researchers see the family unit as a whole as being the key unit of analysis and the focus of intervention. In Australia, many Aboriginal people and members of other oppressed and/or minority ethnic communities who are concerned about domestic violence, also prefer the term 'family violence'. This interpretation seems different in some ways from that of American family violence researchers.
A Practical Routing and MAC Framework for Maximum Lifetime Sensor Telemetry

The recent progress in sensor and wireless communication technologies has enabled the design and implementation of new applications such as sensor telemetry which is the use of wireless sensors to gather more fine-grained information from products, people and places. In this work, we consider a realistic telemetry application in which a large 2-dimensional area is periodically monitored by a sensor network which gathers data from equally spaced sample points. The objective is to maximize the lifetime of the network by jointly selecting the sensing nodes, the node transmission powers and the route to the base station from each sensing node. We develop an optimization-based algorithm OPT-RE, and a low complexity algorithm SP-RE for this purpose, and analyze their dynamics through extensive numerical studies. Our results indicate that SP-RE is a promising algorithm which has comparable performance to that of the more computationally intensive OPT-RE algorithm. The energy consumption is significantly affected by the channel access method, and in this paper, we also compare the effects of the collision-free TDMA, and contention-based CSMA/CA methods.
Research on calibration technology in rail abrasion detection based on machine vision

When using machine vision system to detect rail abrasion, we need to calibrate camera and light plane in order to obtain geometrical relationship between camera and light plane along with coordinates of points on rail profile in world coordinate system. This paper uses camera calibration based on 2D planar calibration target to realize camera calibration. The experiment indicates that it has many advantages such as high accuracy, simple procedures, et al. Using indirect calibration method to conduct light plane calibration, this approach uses target curve with single-pixel width to get the pixel coordinate of feature points so as to reduce the effect on accuracy caused by the width of light.
d-Allose Catabolism ofEscherichia coli: Involvement of alsI and Regulation of als Regulon Expression by Allose and Ribose

ABSTRACT Genes involved in allose utilization of Escherichia coli K-12 are organized in at least two operons,alsRBACE and alsI, located next to each other on the chromosome but divergently transcribed. Mutants defective inalsI (allose 6-phosphate isomerase gene) andalsE (allulose 6-phosphate epimerase gene) were Als−. Transcription of the two allose operons, measured as β-galactosidase activity specified byalsI-lacZ+ oralsE-lacZ+ operon fusions, was induced by allose. Ribose also caused derepression of expression of the regulon under conditions in which ribose phosphate catabolism was impaired.
Event Structure , Unaccusativity , and Locative Inversion

This paper attempts to account for why Chinese locative inversion exhibits crosslinguistically peculiar distributional properties. I argue that the attested crosslinguistic differences are attributed to the differences in the way the socalled “state subevent condition” (Nakajima 2001) is satisfied. Specifically, I claim that it is an operation on the event structure that allows certain nonpassivized transitive verbs to meet the condition. The analysis also receives crosslinguistic support from the Japanese -te aru construction.
Rapid Deployment of a New METIS Language Pair: Catalan-English

We show here the viability of a rapid deployment of a new language pair within the METIS architecture. In order to do it, we have benefited from the approach of our existing Spanish-English system, which is particularly generation intensive. Contrarily to other SMT or EBMT systems, the METIS architecture allows us to forgo parallel texts, which for many language pairs, such as Catalan-English are hard to obtain. In this experiment, we have successfully built a Catalan-English prototype by simply plugging a POS tagger for Catalan and a bilingual Catalan-English dictionary to the English generation part of the system already developed for other language pairs.
Improving Bitmap Index Compression by Data Reorganization

The volume of data generated by scientific applications through observations or computer simulations can reach to the order of the petabytes. This brings up the need for effective and compact indexing methods for efficient storage and retrieval of scientific data. Bitmap indexing has been successfully applied in this domain by exploiting the fact that scientific data are mostly read-only and enumerated or numerical. Bitmap indices can be compressed for efficient storage. In this paper, we study how to reorganize bitmap tables for improved compression rates. Our algorithms are used as a preprocessing step, thus there is no need to revise the current indexing techniques and the query processing algorithms. We propose Gray code ordering algorithm for this NP-Complete problem, which is an in-place algorithm, and runs in linear time in the order of the size of the database. We explore the effect of the order in which columns are evaluated in the Gray code ordering, to further improve the query execution time. Our experimental results on real data sets show that the compression ratio can be improved by a factor of 2 to 10 and the query execution times by a factor of 4 to 7.
EDSS Change Relates to Physical HRQoL While Relapse Occurrence Relates to Overall HRQoL in Patients with Multiple Sclerosis Receiving Subcutaneous Interferon β-1a

Objective. To compare patterns of associations of changes in mental and physical health dimensions of health-related quality of life (HRQoL) over time with relapse occurrence and changes in Expanded Disability Status Scale (EDSS) scores in patients with relapsing multiple sclerosis (RMS). Methods. This 24-month, phase IV, observational study enrolled 334 patients with RMS who received interferon β-1a 44 μg or 22 μg subcutaneously three times weekly. At each 6-month visit, patients completed the Multiple Sclerosis Quality of Life-54 (MSQOL-54) and site investigators assessed EDSS and recorded relapse occurrence. A generalized linear model procedure was used for multivariable analyses (per protocol) that explored unique associations of EDSS score change and relapse occurrence with MSQOL-54 physical health composite score (PCS) and mental health composite score (MCS). Results. HRQoL improved over 2 years among those who completed the study. Occurrence of ≥1 relapse was significantly associated with lower MSQOL-54 PCS and MCS. Changes in EDSS score were significantly associated with MSQOL-54 PCS, but not MCS. Conclusions. HRQoL assessments, particularly those that examine mental health, may provide information on the general health status of patients with RMS that would not be recognized using traditional clinician-assessed measures of disease severity and activity. This trial is registered with ClinicalTrials.gov; identifier: NCT01141751.
DiFi: Fast Distance Field Computation using Graphics Hardware

We present a novel algorithm for fast computation of discretized distance ﬁelds using graphics hardware. Given a set of primitives and a distance metric, our algorithm computes the distance ﬁeld along each slice of a uniform spatial grid by rasterizing the distance functions. It uses bounds on the spatial extent of Voronoi regions of each primitive as well as spatial coherence between adjacent slices to cull the primitives. As a result, it can signiﬁcantly reduce the load on the graphics pipeline. We have applied this technique to compute the Voronoi regions of large models composed of tens of thousands of primitives. For a given grid size, the culling efﬁciency increases with the model complexity. To demonstrate this technique, we compute the medial axis transform of a polyhedral model. In practice, we are able to obtain up to one order of magnitude improvement over earlier algorithms that compute the distance ﬁelds using graphics hardware.