Miracle-dz/UniFAR-FTUs huggingface dataset:
Robust Stochastic Optimal Control for Multivariable Dynamical Systems Using Expectation Maximization

Trajectory optimization is a fundamental stochastic optimal control problem. This paper deals with a trajectory optimization approach for unknown complicated systems subjected to stochastic sensor noise. The proposed methodology assimilates the benefits of conventional optimal control procedure with the advantages of maximum likelihood approaches to deliver a novel iterative trajectory optimization paradigm to be called as Stochastic Optimal Control - Expectation Maximization (SOC-EM). This trajectory optimization procedure exhibits theoretical results which prove that the optimal policy parameters produced by the maximum likelihood technique produce better performance in terms of reduction of cumulative cost-to-go and less stochasticity in the states and actions. Furthermore, the paper provides empirical results which support the superiority of the new technique when applied to a system in presence of measurement noise, compared to some of widely known and extensively employed methodologies.
A Dual-Source Attention Transformer for Multi-Person Pose Tracking

Multi-person pose tracking is an important element for many applications and requires to estimate the human poses of all persons in a video and to track them over time. The association of poses across frames remains an open research problem, in particular for online tracking meth-ods, due to motion blur, crowded scenes and occlusions. To tackle the association challenge, we propose a Dual-Source Attention Transformer that incorporates three core aspects: i) In order to re-identify persons that have been occluded, we propose a pose-conditioned re-identification network that provides an initial embedding and allows to match persons even if the number of visible joints differs between the frames. ii) We incorporate edge embeddings based on temporal pose similarity and the impact of appearance and pose similarity is automatically adapted. iii) We propose an attention based matching layer for pose-to-track association and duplicate removal. We evaluate our approach on Market1501, PoseTrack 2018 and PoseTrack21.
Better approximation guarantees for the NSGA-II by using the current crowding distance

A recent runtime analysis (Zheng, Liu, Doerr (2022)) has shown that a variant of the NSGA-II algorithm can efficiently compute the full Pareto front of the OneMinMax problem when the population size is by a constant factor larger than the Pareto front, but that this is not possible when the population size is only equal to the Pareto front size. In this work, we analyze how well the NSGA-II with small population size approximates the Pareto front of One-MinMax. We observe experimentally and by mathematical means that already when the population size is half the Pareto front size, relatively large gaps in the Pareto front remain. The reason for this phenomenon is that the NSGA-II in the selection stage computes the crowding distance once and then repeatedly removes individuals with smallest crowding distance without updating the crowding distance after each removal. We propose an eficient way to implement the NSGA-II using the current crowding distance. In our experiments, this algorithm approximates the Pareto front much better than the previous version. We also prove that the gaps in the Pareto front are at most a constant factor larger than the theoretical minimum.
Assessing carbon lability of particulate organic matter from δ13C changes following land-use change from C3 native vegetation to C4 pasture

Land-use change from C3 vegetation (δ13C values, –30‰ to –24‰) to C4 vegetation (δ13C values, –14‰ to –11‰) provides a useful quantitative technique for estimating organic C turnover in soil, even when total organic C changes are negligible. We utilised this technique to estimate C turnover in physically fractionated soil organic matter, particulate organic matter C (POM C >250 μm fraction and POM C 250–53 μm fraction), and the 250 μm fraction changed from –25.5 ± 0.1‰ and –25.5 ± 0.3‰ under native vegetation to –20.1 ± 0.5‰ and –19.4 ± 0.2‰ under pasture. Similar, although smaller, differences were observed for other depths and SOC fractions. The SOC turnover periods (years) were 31 ± 6 for the 0–0.1 m depth, 60 ± 5 for the 0.1–0.2 m depth, 55 ± 15 for the 0.2–0.3 m depth, and 63 ± 20 for the 0.3–0.4 m depth; the corresponding turnover periods for the POM C >250 μm fraction were 13 ± 2, 19 ± 5, 14 ± 4, and 12 ± 5 years. The turnover periods of SOC in the POM C 250–53 μm and 250 μm fraction > POM C 53–250 μm fraction = POM C <53 μm fraction = whole SOC.
Damn or be damned: Arno Peters and the Struggle for the 'New Cartography'

In this paper I am concerned essentially with the nature of the competing discourses that the Peters phenomenon engendered within cartographic circles and beyond. My critical review of the Peters phenomena opens with two personal experiences that illustrate the nature of the vociferous debate surrounding Peters’ ideas. These experiences high-light the dangers of the dogmatic attitudes that emerged on both sides:
Improving TCP performance for multihop wireless networks

In this paper, we present a comprehensive performance evaluation of TCP NewReno and TCP Vegas with and without ACK thinning for static multihop wireless IEEE 802.11 networks. Opposed to previous studies, we consider not only IEEE 802.11 operating in ad hoc mode with 2 Mbit/s bandwidth, but also with 5.5 Mbit/s and 11 Mbit/s bandwidths. Simulation results using ns-2 show that TCP Vegas achieves between 15% and 83% more goodput and between 57% and 99% fewer packet retransmissions than TCP NewReno. Considering fairness among multiple TCP flows, we show that using TCP Vegas results in between 21% and 95% fairness improvement compared to TCP NewReno. The reduced amount of packet retransmissions of TCP Vegas also leads to significant savings of energy consumption. The paper gives insight on the particular reasons for such performance advantages of TCP Vegas in comparison to TCP NewReno.
Modeling Learning via Progressive Alignment using Interim Generalizations

There is ample empirical evidence that children can sometimes learn during the course of even a few experimental trials. We propose that one mechanism for this is the use of analogical generalizations constructed in working memory, producing what we call interim generalizations. Prior research suggests that such generalizations can be constructed when there is high similarity between closely spaced items. This paper describes how structure-mapping simulations can be adapted to capture this phenomenon, using automatically encoded stimuli. It is an advance over prior models in that it automatically detects when rerepresentation should be tried and carries it out to improve its performance.
An Examination of Network RTK GPS Services in Great Britain

Abstract As of March 2009, network real-time kinematic (RTK) GPS surveying is available in Great Britain with the aid of two commercial service providers, Leica's “SmartNet” and Trimble's “VRS Now”, both of which rely largely on the Ordnance Survey's “OS Net” network of around 120 continuously operating reference stations. With the aim of testing the performance of Network RTK under both ideal and less-ideal conditions (greater distances and elevation differences from the nearest reference stations, proximity to the edges of OS Net, and increased susceptibility to ocean tide loading effects), we have tested the positional accuracy of both commercial Network RTK systems by comparison with precise coordinates determined using the Bernese scientific GPS processing software, at six representative locations spanning England and Wales. We find that the coordinate quality measures provided by the Network RTK solutions are overall representative of the actual coordinate accuracy, which is typically 10-20 mm in plan and 15-35 mm in height, and can be successfully used to identify outliers. Positional accuracy tends to be poorest outside of the bounds of OS Net and at greater elevation differences from nearby reference stations. Averaging of coordinates over two short windows separated by 20-45 minutes can be used to achieve moderate improvements in coordinate accuracy without the need for single long occupations of sites.
Ecology of desert-dwelling giraffe Giraffa camelopardalis angolensis in northwestern Namibia

The population size and range of giraffe Giraffa camelopardalis have been greatly reduced in Africa in the past century, resulting in geographical isolation of local populations and some herds surviving at the edge of the species’ preferred range. Numerous factors have contributed to these declines, but historical analysis indicates that habitat loss and fragmentation, human encroachment, disease and poaching are the main threatening processes. These processes can be expected to continue to impact on giraffe populations, particularly as human populations grow and needs for land and resources increase. This study used field data and laboratory analyses to investigate the taxonomy, behaviour and ecology of desert-dwelling giraffe Giraffa camelopardalis angolensis in the northern Namib Desert. This population resides at the extreme of the giraffe’s range. My research also complements the community-based natural resource management (CBNRM) program of the Namibian government, and provides baseline data on the current population status and structure of giraffe in the Kunene Region. The field data, genetic, habitat and forage samples used in this study were collected by myself and a number of research assistants over a period of two years (2001 to 2003), following preliminary research that I undertook between 1999 and 2001. Laboratory analysis of genetic samples was conducted by Dr R. Brenneman and his team at Henry Doorly Zoo, Omaha, NB. , as well as by Mr D. Brown at UCLA, CA. Mr W. Gawa! nab and his team at the agricultural laboratory, Ministry of Agriculture, Water and Rural Affairs, Namibia, conducted chemical analyses on plant samples that form part of the giraffe’s diet. The genetic architecture of Namibian giraffe was investigated, including the samples from the desert-dwelling giraffe of the northern Namib Desert and giraffe from Etosha National Park. The results were compared with genetic profiles of giraffe subspecies throughout Africa, but in particular with G. c. giraffa which is the currently-accepted nomenclature of the Namibian giraffe. Results indicated that the Namibian giraffe has five unique haplotypes and is genetically distinct from G. c. giraffa or any other extant subspecies; it is considered here, tentatively, to represent G. c. angolensis. Furthermore, the Namibian
Observational evidence for a cross frontal heat pump in the Southern Ocean

Transient eddies in the Southern Ocean play a central role in the global thermohaline circulation. Meridional exchange of heat and salt is not geographically uniformly distributed, but may be concentrated in a number of specific regions where high levels of mesoscale turbulence are generated. We have identified a powerful example of such a region at the South‐West Indian Ridge in which cross‐ACC heat transport is dependent on eddy shedding. We show that Antarctic eddies are shed across the APF into the Subantarctic at an average of 3 a year and that they have a longevity of 11 months. Furthermore, we calculate the meridional heat and salt deficit of −5.6 ± 1.5 × 1019 J and −8.1 ± 1.5 × 1011 kg relative to the surrounding Subantarctic waters of one such eddy. Despite the importance of this process, eddy heat transport remains one of the most poorly observed quantities in the Southern Ocean.
Privacy Enhancing Technologies: A Review

Organisations handle employees', customers' and third parties' Personally Identifiable Information (PII) in a number of ways and for a variety of reasons; when doing this, it is important that privacy is taken into account. Privacy Enhancing Tech- nologies (PETs) provide a mechanism that helps with this, and can be used in conjunc- tion with higher level policy definition, human processes, training, etc. In this paper we conduct a brief survey of Privacy Enhancing Technologies (PETs) in recent years and show how these may help address different types of privacy harm to employees, customers and, more generally, to the data subjects (Institute, 2009).
Bayesian estimation of basal conditions on Rutford Ice Stream, West Antarctica, from surface data

Abstract The determination of basal properties on ice streams from surface data is formulated as a Bayesian statistical inference problem. The theory is applied to a flowline on Rutford Ice Stream, West Antarctica. Estimates of bed topography and basal slipperiness are updated using measurements of surface topography and the horizontal and vertical components of the surface velocity. The surface topography is allowed to vary within measurement errors. We calculate the transient evolution of the surface until rates of surface elevation change are within limits given by measurements. For our final estimation of basal properties, modelled rates of elevation change are in full agreement with estimates of surface elevation changes. Results are discarded from a section of the flowline where the distribution of surface residuals is not consistent with error estimates. Apart from a general increase in basal slipperiness toward the grounding line, we find no evidence for any spatial variations in basal slipperiness. In particular, we find that short-scale variability (<10 × ice thickness) in surface topography and surface velocities can be reproduced by the model by variations in basal topography only. Assuming steady-state conditions, an almost perfect agreement is found between modelled and measured surface geometry, suggesting that Rutford Ice Stream is currently close to a steady state.
Bearing Capacity of Strip Footing above Void

The bearing capacity behavior of strip footing located above a continuous void in silty clay soil was investigated experimentally and analytically. The experiment was performed in a test tank which contained a compacted silty clay. The analysis was made by using the finite element method in which the test soil was treated as an elastic perfectly plastic material. Results of the study indicate that the bearing capacity of footing above a void can be analyzed successfully by using the finite element method of analysis. For each footing, there exists a critical depth below which the presence of the void has negligible influence on the footing performance. When the void is located above the critical depth, the bearing capacity of the footing varies with various factors, such as the size and location of the void and the depth of foundation. Graphs relating the bearing capacity with the influencing factors investigated are developed. These graphs provide a data base useful for design of continuous footing cente.
Effects of automated transcription quality on non-native speakers' comprehension in real-time computer-mediated communication

Real-time transcription has been shown to be valuable in facilitating non-native speakers' comprehension in real-time communication. Automated speech recognition (ASR) technology is a critical ingredient for its practical deployment. This paper presents a series of studies investigating how the quality of transcripts generated by an ASR system impacts user comprehension and subjective evaluation. Experiments are first presented comparing performance across three different transcription conditions: no transcript, a perfect transcript, and a transcript with Word Error Rate (WER) =20%. We found 20% WER was the most likely critical point for transcripts to be just acceptable and useful. Then we further examined a lower WER of 10% (a lower bound for today's state-of-the-art systems) employing the same experimental design. The results indicated that at 10% WER comprehension performance was significantly improved compared to the no-transcript condition. Finally, implications for further system development and design are discussed.
Geometric bed roughness and the bed state storm cycle

[1] Temporal variation in the geometric roughness of the mobile sandy seabed during wave forcing events is investigated as a function of bed state. The bed states include irregular ripples, cross ripples, linear transition ripples, and flat bed, each appearing repeatedly within a different range of wave energies, as part of the bed state storm cycle. Ripple wavelengths determined from ensemble-averaged roughness spectra indicate that irregular and cross ripples are suborbital, whereas linear transition ripples are anorbital. The observed ripple steepnesses indicate that irregular and linear transition ripples fall slightly below Nielsen's (1981) field data relation, whereas cross ripple steepnesses are anomalously low in comparison. Time series of geometric roughness are coherent across spatial frequency. Abrupt changes in geometric roughness occurred on timescales of ∼3 h on average during both the onset and the waning stages of storm events: i.e., for both decreasing and increasing roughness, respectively. Predicted response times, based on ripple volume and bed load transport rate, are in agreement with the observations when the best fit form of the Meyer-Peter and Muller (1948)-type bed load relation obtained by Ribberink (1998) is used. In contrast, the more standard form of this relation and the associated parameters yield predicted response times much shorter than those observed.
Performance and Benefits of Zero Maintenance Air Induction Systems

Engine air filtration technologies currently used in air induction systems typically utilize pleated paper or felt type air filters. These air filter designs have been used for many years in panels, cylindrical or round (pancake type) type air cleaners. Pleated air filters are specifically designed to be serviceable and hence their performance is inherently limited by vehicle under-hood packaging and manufacturing constraints. Due to these constraints, majority of air cleaner designs are not optimized for engine filtration and air flow management under the hood. Studies show that use of low performing serviceable aftermarket air filters significantly affect the performance and durability of engine air cleaners [9]. High mileage studies confirm that engine durability, service issues, warranty field returns and customer satisfaction was affected by use of aftermarket filter brands. Innovative air cleaner designs are required to maximize filtration performance, improve flow management, extend air cleaner service life and improve engine durability. Filtration characteristics of reticulated porous foams were studied and evaluated as a potential solution. Reticulated foam media has a very open structure, which allows it to have a relatively high dust holding capacity (DHC) and capture efficiency. The potential benefits of reticulated foam filters are longer life, competitive cost and flexibility in packaging. A foam filter model was also developed to predict performances of multi-layer reticulated foam filters. Model predictions for a four layer foam filter design have been presented and discussed. A new Long Life Filtration System was developed for OEM (Original Equipment Manufacturer) applications (2003/2004 Ford Focus Vehicle) and requirements. This new technology uses a unique multi-layered reticulated foam media which does not need servicing or maintenance for the life of the vehicle [150K+ miles]. This technology also provides some unique advantages over the traditional serviceable air induction filters. Accelerated field evaluations are also presented to support the new Visteon technology using Long Life Filtration System. These studies show the viability and flexibility of multi-layer foam designs.
Evaluation of Spatial Distortion in Multichannel Audio

—Despite the recent proliferation of spatial audio technologies, the evaluation of spatial quality continues to rely on subjective listening tests, often requiring expert listeners. Based on the duplex theory of spatial hearing, it is possible to construct a signal model for frequency-independent spatial distortion by accounting for inter-channel time and level differences relative to a reference signal. By using a combination of least-square optimization and heuristics, we propose a signal decomposition method to isolate the spatial error from a processed signal. This allows the computation of simple energy-ratio metrics, providing objective measures of spatial and non-spatial signal qualities, with minimal assumption and no dataset dependency. Experiments demonstrate robustness of the method against common signal degradation as introduced by, e.g., audio compression and music source separation.
A Velocity Field for Some Passive Earth Pressure Problems

Synopsis A simple velocity field is developed for the passive earth pressure problem of the displacement of a rough plane wall into a mass of dry sand. Three modes of wall displacement are considered: wall rotation about the top, wall rotation about the toe and wall translation. The validity of the velocity field for the three cases is discussed. The pattern of the velocity field and the velocity boundary conditions enables predictions to be made of the strain fields associated with the three modes of wall movement and these predictions are compared with experimental observations. The velocity field also predicts the location and sequence of the rupture surfaces that occur in dense sand and leads to an understanding of the differences in the experimentally observed strain fields and wall stress distributions. This Paper follows on from an earlier paper (James and Bransby, 1970) in which the boundary stresses and the predicted principal stress directions in the mass were compared with measured boundary str.
Shallow structure of the Landers Fault Zone from explosion-generated trapped waves

With fault-zone trapped waves generated by near-surface explosions within the fault zone of the 1992 Landers, California, earthquake and recorded by linear seismic arrays deployed along and across the fault, we have delineated the shallow seismic structure near the 30-km-long southern rupture on the Johnson Valley fault. The explosion-excited trapped waves with relatively large amplitude and long-duration wave train after the S waves are similar to those generated by aftershocks [Li et al, 1994a, b] but have lower frequencies and travel more slowly. Coda-normalized amplitude spectra of explosion-excited trapped waves show a maximum at ∼2 Hz, which decreases rapidly with the station offset from the fault trace on the cross-fault profiles. Normalized amplitudes of trapped waves on the along-fault profile also decreased with distance between the explosion and station, giving an apparent Q of ∼18 at 1–2 Hz in the fault zone for the shot near the profile. The dispersion of trapped waves from 0.6 to 2.5 Hz recorded on this along-fault profile implies a shear velocity of ∼1.0 km/s for the fault zone and ∼1.8 km/s for the wall rock, while the data from the farther shot show an increase in velocity and Q with depth. Measured group velocities and Q values were used as constraints in the numerical modeling of trapped waves on cross-fault and along-fault profiles. Results reveal that the shallow Johnson Valley fault is marked by a zone 250 m wide where the shear velocity is 1 km/s and Q is 20. Calculation of finite difference synthetics for a depth-varying fault structure show that these model parameters apply to the depth of ∼1 km, below which the fault zone shear velocity increases to 1.9 km/s and Q increases to 30.