Miracle-dz/UniFAR-FTUs huggingface dataset:
Scalable Methods for Graph-Based Unsupervised and Semi-Supervised Learning

Data often comes in the form of a graph. When it does not, it often makes sense to represent it as a graph for learning tasks that rely on the similarities or relationships between data points. As data size grows, traditional methods for learning on graphs often become computationally intractable in terms of time and space requirements. We describe new methods for graph-based clustering and semi-supervised classification with a focus on scalability. We show how these methods can be efficiently extended to work on non-graph data, and we demonstrate their application and effectiveness on a wide variety of datasets that includes social and citation networks, political blogs, document collections, noun phrase-context co-occurrences, and geolocations.
Experimental comparison of electroosmotic consolidation of wenzhou dredged clay sediment using intermittent current and polarity reversal

ABSTRACT The electroosmosis method is regarded especially suitable for the disposal of dredged clay sediment, but its excessive power consumption and electrode corrosion has limited its widespread application. Thus, intermittent current and polarity reversal are applied to offset its drawbacks. This study aims to examine the consolidation effect and internal relationship between the two approaches and optimize their time settings. Laboratory tests were performed with the same intermittent ratio and different reversal ratios. The test results demonstrated that intermittent current with comparatively greater intermittent times and a higher reversal ratio achieved a better drainage effect during the electroosmosis process and soil uniformity after test and the drainage in the reverse direction was lesser than that in the forward direction. The drainage effect during the power-off mode for 1 h was equivalent to that in the reverse electrifying mode for 0.2–0.25 h. Sharp increases in the current were induced by each intermittent current and polarity reversal. Although the polarity reversal approach improved the drainage effect, it partly increased the energy consumption. Compared with the intermittent current approach, reducing the reverse electrifying period to improve soil consolidation is feasible for application to engineering practice.
Solution of alternating-line processes on modern parallel computers

The aim of this paper is the study of different methods for the solution of alternating-line problems, taking into account the evolution of architectural parameters on modern parallel computers, i.e. processors, memory hierarchy, and interconnection network performance. Three different kinds of solvers are studied: The Pipelined Gaussian Elimination scheme, the Matrix Transposition scheme, and the new one which is presented in this paper: the Mapping Transposition scheme, whose performance clearly betters, in many cases, that obtained by all the other methods, due to its better fitting to the characteristics of modern parallel computers. The experimental results have been obtained on a Cray T3E and on an SGI Origin 2000, up to 512 and 32 processors, respectively.
Effort Prediction in Iterative Software Development Processes -- Incremental Versus Global Prediction Models

Estimation of development effort without imposing overhead on the project and the development team is of paramount importance for any software company. This study proposes a new effort estimation methodology aimed at agile and iterative development environments not suitable for description by traditional prediction methods. We propose a detailed development methodology, discuss a number of architectures of such models (including a wealth of augmented regression models and neural networks) and include a thorough case study of Extreme Programming (XP) in two semi-industrial projects. The results of this research evidence that in the XP environment under study the proposed incremental model outperforms traditional estimation techniques most notably in early phases of development. Moreover, when dealing with new projects, the incremental model can be developed from scratch without resorting itself to historic data.
High‐resolution deep tectonic tremor locations beneath the San Andreas Fault near Cholame, California, using the double‐pair double‐difference location method

We determine high‐precision deep tectonic tremor locations beneath the San Andreas Fault (SAF) near Cholame, California, region by using a newly developed double‐pair double‐difference location method and a new 3‐D Vs model. Compared to the previous results, newly determined tremor locations are more consistent with known low‐frequency earthquake locations and are more concentrated along the SAF. New tremor locations near Cholame show clear contrast in the predominant depth of the tremor activity across the SAF and also show contrasts in the degree of periodic behavior both along and across the SAF. They collectively define a very special tremor generation region (VSTR) near the intersection corner between the SAF and the adjacent San Juan Fault (SJF). In the VSTR, new locations reveal some isolated tremor clusters, which may occur on multiple deep fault patches. For these isolated clusters, some are closer to the SAF and some are closer to the SJF, implying that both the SAF and SJF may extend to the ductile lower crust. Possible interaction between the SAF and SJF in the lower crust beneath the VSTR, combined with the trapped high‐pressure fluids, may explain the strong tremor activity, the isolated tremor clusters, and the characteristic tremor occurrence patterns and depth distributions in this region.
Edge effect and its impact upon the accuracy of 2D and 3D modelling using laser scanning

The edge effect is a measurement error resulting from the reflection of the laser beam on the adjacent walls, or by its breaking on the edges. Coordinates of points in such cases are determined by averaging the measurements in several areas, resulting in their incorrect positioning in space. Corner points are determined with the same accuracy as the other (flat) elements of the scanned object. This effect is frequently mentioned in publications, which typically state the reasons and mechanisms of the error thus occurred. However, there is a lack of specific examples, showing the impact of the edge effect on the quality and accuracy of geodetic and cartographic reports. In this paper, the authors present sample case studies of the 2D and 3D representation of the test object. The selected corner elements, as well as the vector elements fitted into a cloud of points, show the discrepancy between the breaking points in the drawing (model), and the curved surface of the point cloud. On the basis of the known geometry of the building, distances were determined between the corner points and their representatives on the cloud. In this way, we were able to determine the accuracy of corner points’ presentation by means of the cloud of points, and therefore, we were able to determine the size of the edge effect in specific cases.
When Is Free/Open Source Software Development Faster, Better, and Cheaper than Software Engineering?

1. This chapter draws attention to the question of determining the conditions when free/open source software development may represent a significant alternative to modern software engineering techniques for developing large-scale software systems. F/OSSD often entails shorter development times that can produce higher quality systems, and incur lower costs than may be realized through developing systems according SE techniques. Understanding why and how this may arise is the focus of this chapter. It presents, analyzes, and compares data collected from different F/OSSD projects, including an in-depth case study, to help develop such an understanding. The goal of this chapter is to determine the circumstances and conditions when F/OSSD represents a viable alternative to SE for the development of complex software systems. In particular, the chapter seeks to contrast differences observed in the arrangement and tooling of their respective software development practices, production resources, technical regimes, and community practices in which they are embedded. This in turn may then help identify how the practice and principles of SE might be improved.
– Automatic Veriﬁcation and Analysis of Complex Systems

The recently presented constraint solver HySAT tackles the in general undecidable problem of solving mixed Boolean and non-linear arithmetic constraint formulae over the reals involving transcendental functions. The algorithmic core of HySAT is the iSAT algorithm, a tight integration of the Davis-Putnam-Logemann-Loveland algorithm with interval constraint propagation enriched by enhancements like conﬂict-driven clause learning and non-chronological backtracking. However, it was an open question whether HySAT’s conﬂict analysis scheme, an adapted ﬁrst unique implication point technique as applied in most modern SAT solvers, performs favorably compared to other schemes. In this paper, we compare several conﬂict analysis heuristics to answer this question. Furthermore, we consider the integration of restarts into the iSAT algorithm and investigate their impact. For our empirical results we use benchmarks from the hybrid systems domain.
The demography of Tanzania: an analysis of the 1973 National Demographic Survey of Tanzania. Vol 6.

The 1973 National Demographic Survey (NDS) of Tanzania shows that mainland Tanzania has experienced an increase in fertility. Current total fertility rate is 6.3. However although fertility appears to have increased in all selected regions the increase may have been exaggerated by errors of omission of live births birth misplacement and age misreporting. Although marriage is universal in Tanzania marriage instability in the form of polygamy remarriage and divorce is high at relatively early ages. Education of females can cut the proportion of women in unstable marriages in half. In its 1st 5-year plan Tanzania set itself 3 major long-term objectives 1 of which was to raise the expectation of life to 50 years. The NDS data show that in 3 regions (Arusha Kilimanjaro and Tanga) this goal has already been reached. Many other regions are close to the goal with a life expectancy of over 47. Education is found to have an influence on mortality. Infant and child mortality fall with more years of education of the mother. The NDS study gives particular attention to the effect of socioeconomic development on fertility. In the early stages of socioeconomic development fertility tends to rise. Socioeconomic development affects fertility through changes in marital habits. A decline in marriage instability both in the form of polygamy and in the form of divorce and remarriage usually accompanies socioeconomic development in rural areas. Improvements in economic and social conditions in Tanzania in the near future will lead to a drop in mortality and a rise in fertility. Currently the prosperous and healthy zones (e.g. Northeast Highlands) are showing the highest fertility the lowest proportion of childless women and the highest life expectancy while the economically and socially disadvantaged groups are exhibiting low fertility and high mortality. Analysis by mode of life zone by cluster and by household confirms the conclusion that socioeconomic development removes limiting factors in fertility without changing peoples attitude towards family size; this explains why fertility is high in the more economically developed regions than in the less economically developed regions and why fertility is still rising.
Indoor Air Quality and Outdoor Air Requirement for Personal Ventilation System in Office Spaces

The study presented in this paper is a continuation of Abdelmaksoud and Khalil’s [1-2] studies on the occupant's thermal comfort in office spaces. That study was performed using the computational fluid dynamics (CFD) method and recommended the use of modern ventilation system that combines the effect of displacement ventilation and personal ventilation systems. This ventilation system provides an ideal thermal comfort for the occupant in the office. But, the thermal comfort is independent of the indoor air quality, which was not included in Abdelmaksoud and Khalil’s study. Poor indoor air quality can induce health problems and lower the activity level. The carbon dioxide (CO2) is used in the present study as an indicator of the air quality in the space. The CO2 is emitted with human’s respiration and correlates with the human metabolic activity. ASHRAE [3] recommends a maximum limit of 700 ppm differential between indoor and outdoor levels of CO2 concentration. In the present paper, we investigated the CO2 concentration distribution around the occupant location in the office cubicle configuration that was presented in the earlier papers of Abdelmaksoud and Khalil [1-2]. The objectives were to: (1) investigate the CO2 concentration level in the breathing zone of the human, and (2) recommend a minimum amount of outdoor air ventilation rate that maintains the CO2 concentration in the breathing zone below the maximum allowable limit. To achieve these objectives, several CFD cases were studied and their results are presented in this paper.
Buy-at-Bulk Network Design with Protection

We consider approximation algorithms for buy-at-bulk network design, with the additional constraint that demand pairs be protected against edge or node failures in the network. In practice, the most popular model used in high speed telecommunication networks for protection against failures, is the so-called 1+1 model. In this model, two edge or node-disjoint paths are provisioned for each demand pair. We obtain the first non-trivial approximation algorithms for buy-at-bulk network design in the 1+1 model for both edge and node-disjoint protection requirements. Our results are for the single-cable cost model, which is prevalent in optical networks. More specifically, we present a constant-factor approximation for the single-sink case, and an O(log3 n) approximation for the multi-commodity case. These results are of interest for practical applications and also suggest several new challenging theoretical problems.
Structural evidence for two-stage binding of mitochondrial ferredoxin 2 to the core iron-sulfur cluster assembly complex

Iron-sulfur (FeS) clusters are ubiquitous metallocofactors that are essential for life. In eukaryotes, FeS cluster biosynthesis begins with the de novo assembly of a [2Fe-2S] cluster by the core iron-sulfur cluster assembly (ISC) complex in the mitochondrial matrix. This complex comprises the scaffold protein ISCU2, the cysteine desulfurase subcomplex NFS1-ISD11-ACP1, the allosteric activator frataxin (FXN) and the electron donor ferredoxin 2 (FDX2). The interaction of FDX2 with the complex remains unclear. Here, we present cryo-EM structures of the FDX2-bound core ISC complex and show that FDX2 and FXN compete for overlapping binding sites during [2Fe-2S] cluster biosynthesis. FDX2 binds in two conformations; in the ‘distal’ conformation, helix F of FDX2 shows loose electrostatic interaction with an arginine patch of NFS1, while in the ‘proximal’ conformation this interaction tightens and the FDX2-specific C terminus forms contacts with NFS1; in this conformation, the [2Fe-2S] cluster of FDX2 is close enough to the ISCU2 FeS cluster assembly site for rapid electron transfer.
Modeling Neuromotor Adaptation to Pulsed Torque Assistance During Walking

We establish the validity of error-based and usedependent learning models to describe the response of healthy individuals to robot-aided training of propulsion via a robotic exoskeleton, and propose a modified UDL model that accounts for both use-dependent and error-based learning during and after training. We formulated five different state-space models to describe the stride-by-stride evolution of metrics of propulsion mechanics (hip extension – HE - and propulsive impulse - PI) during and immediately after exposure to robot-assisted training, applied by a unilateral hip/knee robotic exoskeleton for 200 consecutive strides. The five state-space models included a single-state model, a two-state model, a two-state fast and slow model, a UDL model, and a modified UDL model requiring 4, 9, 5, 3, and 4 parameters, respectively. The coefficient of determination (R2) and Akaike information criterion (AIC) values are calculated to quantify the goodness of fit of each model during and after exposure to robotic training. Model fit was conducted both at the group level and at the individual participant level, for both outcome measures. At the group level, the modified UDL model shows best goodness-of-fit compared to other motor adaptation models in AIC values in 15/16 conditions. For participant-specific level, both the modified UDL and the complete two-state model have significantly better goodness-of-fit compared to the other models. In summary, the modified UDL model is a simple 4- parameter model that achieves similar goodness-of-fit compared to a complete two-state model requiring 9 parameters. As such, the modified UDL model is a promising model to describe the stride-by-stride response of propulsion mechanics in robotaided gait training.
Incomplete remyelination via endogenous or therapeutically enhanced oligodendrogenesis is sufficient to recover visual cortical function

Myelin loss induces deficits in action potential propagation that result in neural dysfunction and contribute to the pathophysiology of neurodegenerative diseases, injury conditions, and aging. Because remyelination is often incomplete, better understanding endogenous remyelination and developing remyelination therapies that seek to restore neural function are clinical imperatives. Here, we used in vivo two-photon microscopy and electrophysiology to study the dynamics of endogenous and therapeutic-induced cortical remyelination and functional recovery after cuprizone-mediated demyelination in mice. We focused on the visual pathway, which is uniquely positioned to provide insights into structure-function relationships during de/remyelination. We show that endogenous remyelination is driven by recent oligodendrocyte loss and is highly efficacious following mild demyelination, but fails to restore the oligodendrocyte population when high rates of oligodendrocyte loss occur too quickly. Testing a novel thyromimetic compared to clemastine fumarate, we find it better enhances oligodendrocyte gain during remyelination and hastens recovery of neuronal function. Surprisingly, its therapeutic benefit was temporally restricted, and it acted exclusively following moderate to severe demyelination to eliminate endogenous remyelination deficits. However, complete remyelination is unnecessary as partial oligodendrocyte restoration was sufficient to recover visual neuronal function. These findings advance our understanding of remyelination and its impact on functional recovery to inform future therapeutic strategies.
The Stochastic Matching Problem with (Very) Few Queries

Motivated by an application in kidney exchange, we study the following stochastic matching problem: we are given a graph G(V,E) (not necessarily bipartite), where each edge in E is realized with some constant probability p > 0 and the goal is to find a maximum matching in the realized graph. An algorithm in this setting is allowed to make queries to edges in E in order to determine whether or not they are realized. We design an adaptive algorithm for this problem that, for any graph G, computes a (1-ε)-approximate maximum matching in the realized graph Gp with high probability, while making O(log(1/ε p)/ε p queries per vertex, where the edges to query are chosen adaptively in O(log(1/ε p)/ε p rounds. We further present a non-adaptive algorithm that makes O(log(1/ε p)/ε p queries per vertex and computes a (1/2--ε)-approximate maximum matching in Gp with high probability. Both our adaptive and non-adaptive algorithms achieve the same approximation factor a the previous best algorithms of Blum etal (EC 2015) for this problem, while requiring exponentially smaller number of per-vertex queries (and rounds of adaptive queries for the adaptive algorithm). Our results settle an open problem raised by Blum etal by achieving only a polynomial dependency on both ε and p. Moreover, the approximation guarantee of our algorithms is instance-wise as opposed to only being competitive in expectation as is the case for Blum etal. This is of particular relevance to the key application of stochastic matching in kidney exchange. We obtain our results via two main techniques, namely matching-covers and vertex sparsification that may be of independent interest.
De Novo Sensorimotor Skill Learning Through Reuse of Movement Components

Recent theories of sensorimotor control propose that complex movements are constructed by combining simpler output-generating neural processes. Composing together reusable elements allows a rich variety of movements to be generated using a limited set of neural representations, but it may also impose limits on how new sensorimotor skills can be learned. If skill learning requires modification of existing compositional units, then other skills using the same components may be harmed when the new one is learned. Alternatively, if new skills simply reuse existing units, the repertoire of available units may impose limits on what skills can be learned. In this study, we used a myoelectric interface to explore whether learning a novel coordinated control task requires modification of the existing repertoire of output-generating components. Over five sessions on five consecutive days, participants learned to trace a series of trajectories using a computer cursor controlled by coordinated activation of two muscles. The timing of the generated cursor trajectory and its shape relative to the target improved for conditions trained with post-trial visual feedback. Improvements in timing transferred to all untrained conditions, but improvements in shape transferred only to untrained conditions requiring the trained order of muscle activation. Notably, all muscle outputs in the final session could already be generated during the first session. These results suggest that participants learned the new task by independently improving the selection and timing of existing output-generating components. This tendency toward reuse may help to protect existing skills from interference during learning of new skills. Significance Statement Complex movements may be generated by selecting and combining elements from a repertoire of movement-generating neural processes. It remains unclear if these processes are reused or modified when learning entirely new motor skills. In this study, we used a novel human-computer interface task to test this. Over five sessions, participants learned to trace a series of cursor trajectories by coordinating the activation of two muscles. We found that participants tended to reuse the same muscle contractions for different variants of the task, and that performance improvements were attributable to improvements in the choice and timing of muscle contractions. Our results demonstrate that learning of new complex movements does not necessarily require changes to the neural motor repertoire.