Miracle-dz/UniFAR-FTUs huggingface dataset:
Braess's paradox in expanders

Expander graphs are known to facilitate effective routing and most real‐world networks have expansion properties. At the other extreme, it has been shown that in some special graphs, removing certain edges can lead to moreefficient routing. This phenomenon is known as Braess's paradox and is usually regarded as a rare event. In contrast to what one might expect, we show that Braess's paradox is ubiquitous in expander graphs. Specifically, we prove that Braess's paradox occurs in a large class of expander graphs with continuous convex latency functions. Our results extend previous work which held only when the graph was both denser and random and for random linear latency functions. We identify deterministic sufficient conditions for a graph with as few as a linear number of edges, such that Braess's Paradox almost always occurs, with respect to a general family of random latency functions. © 2012 Wiley Periodicals, Inc. Random Struct. Alg. , 2012
Exploring the Symbolic/Subsymbolic Continuum: A case study of RAAM

It is di cult to clearly de ne the symbolic and subsymbolic paradigms; each is usually described by its tendencies rather than any one de nitive property. Symbolic processing is generally characterized by hard-coded, explicit rules operating on discrete, static tokens, while subsymbolic processing is associated with learned, fuzzy constraints a ecting continuous, distributed representations. In addition, programming languages such as Lisp and mechanisms such as Turing machines are typically associated with the symbolic paradigm, while connectionism is frequently associated with the subsymbolic paradigm. Debates contrasting the two paradigms sometimes center on these mechanisms, for example comparing the capabilities of Turing machines with those of connectionist networks (see Adams, Aizawa, and Fuller in this volume). However, connectionist networks can be proven to be computationally equivalent to the abstract notion of Turing machines [Franklin and Garzon, 1990]. Therefore the computational mechanism is not the crucial issue in separating the symbolic and subsymbolic paradigms. What then is the crucial issue? We believe there are three major issues which distinguish the symbolic paradigm from the subsymbolic paradigm: (1) the type of representations; (2) the style of composition; and (3) the functional characteristics. We have summarized the key elements of these di erences between the two paradigms in Table 1. However, most cognitive science and classical arti cial intelligence (AI) models cannot be completely characterized as either purely symbolic or purely subsymbolic using these criteria. Instead, most models fall somewhere in between the two extremes, or in the so-called \Gap. " For this reason, it seems appropriate to view the paradigms as de ning two opposite corners of a three-dimensional continuum as shown in
Synergistic roles of climate warming and human occupation in Patagonian megafaunal extinctions during the Last Deglaciation

Patagonian megafaunal extinctions reveal synergistic roles of climate change and human impacts. The causes of Late Pleistocene megafaunal extinctions (60,000 to 11,650 years ago, hereafter 60 to 11.65 ka) remain contentious, with major phases coinciding with both human arrival and climate change around the world. The Americas provide a unique opportunity to disentangle these factors as human colonization took place over a narrow time frame (~15 to 14.6 ka) but during contrasting temperature trends across each continent. Unfortunately, limited data sets in South America have so far precluded detailed comparison. We analyze genetic and radiocarbon data from 89 and 71 Patagonian megafaunal bones, respectively, more than doubling the high-quality Pleistocene megafaunal radiocarbon data sets from the region. We identify a narrow megafaunal extinction phase 12,280 ± 110 years ago, some 1 to 3 thousand years after initial human presence in the area. Although humans arrived immediately prior to a cold phase, the Antarctic Cold Reversal stadial, megafaunal extinctions did not occur until the stadial finished and the subsequent warming phase commenced some 1 to 3 thousand years later. The increased resolution provided by the Patagonian material reveals that the sequence of climate and extinction events in North and South America were temporally inverted, but in both cases, megafaunal extinctions did not occur until human presence and climate warming coincided. Overall, metapopulation processes involving subpopulation connectivity on a continental scale appear to have been critical for megafaunal species survival of both climate change and human impacts.
A Linear-Programming Approximation of AC Power Flows

Linear active-power-only power flow approximations are pervasive in the planning and control of power systems. However, AC power systems are governed by a system of nonlinear nonconvex power flow equations. Existing linear approximations fail to capture key power flow variables, including reactive power and voltage magnitudes, both of which are necessary in many applications that require voltage management and AC power flow feasibility. This paper proposes novel linear-programming models (the LPAC models) that incorporate reactive power and voltage magnitudes in a linear power flow approximation. The LPAC models are built on a polyhedral relaxation of the cosine terms in the AC equations as well as Taylor approximations of the remaining nonlinear terms. Experimental comparisons with AC solutions on a variety of standard IEEE and Matpower benchmarks show that the LPAC models produce accurate values for active and reactive power, phase angles, and voltage magnitudes. The potential benefits of the LPAC model.
Inventory and Functional Characterization of the HAK Potassium Transporters of Rice1

Plants take up large amounts of K+ from the soil solution and distribute it to the cells of all organs, where it fulfills important physiological functions. Transport of K+from the soil solution to its final destination is mediated by channels and transporters. To better understand K+ movements in plants, we intended to characterize the function of the large KT-HAK-KUP family of transporters in rice (Oryza sativacv Nipponbare). By searching in databases and cDNA cloning, we have identified 17 genes (OsHAK1–17) encoding transporters of this family and obtained evidence of the existence of other two genes. Phylogenetic analysis of the encoded transporters reveals a great diversity among them, and three distant transporters, OsHAK1, OsHAK7, and OsHAK10, were expressed in yeast (Saccharomyces cerevisiae) and bacterial mutants to determine their functions. The three transporters mediate K+ influxes or effluxes, depending on the conditions of the experiment. A comparative kinetic analysis of HAK-mediated K+ influx in yeast and in roots of K+-starved rice seedlings demonstrated the involvement of HAK transporters in root K+ uptake. We discuss that all HAK transporters may mediate K+ transport, but probably not only in the plasma membrane. Transient expression of the OsHAK10-green fluorescent protein fusion protein in living onion epidermal cells targeted this protein to the tonoplast.
Computer methods for sampling from the exponential and normal distributions

distributed raw, dora m~m}~. rs into expo~e~ttaRy a=d normally dis~rib~ed q~mntilies~ W. ~e most ef~kien~ ones are compared, i~ terms of memory reqairemenN a~'~d sNeed, wi#~ some ne~' a~gori~bms, A rmmber of pro<edures conver~ Tayk~f seNes expaf~siN~s directly i~to samp|ing ste~, an approach ~hteh may be ~¢~t for sampling from any eor~inum~;s distributiom For the ex~por~{~fial dNtribu~io~ a definite recommemlation ¢a~ ~ made, ~hereas in #~e case of She =ormat d on ~here remaif~s a choice b.etwee+~ slower a+~d shorter NgoriNms and faster b~,¢t space er~mNg meibcv&, This article reports research on generating random samples ~hat are either expone~tiafly or ~ormally dis-{ribmed. Compmadona! experie~ce on an ,BM460 (model 50) compater is givef~. For some of' the algo-rkbms ~imes and core requirements o~ a c~c 64093 are also reporged. Section 2 introduces some general tools. These :are ~he accep{anceeejecdon tec~haiqae for continuous distri-bunions and Marsagha s table method ~. ~r discrete distri-bmions in the form required in the later parts of the article A more general method for sampling from a dis{ribmion wkh polynomial density is added. Section 3 deals with ~i)ar algorithms for sampling from the exponential distrib~tion. The taat one is an adaptation of a method by Marsaglia and Sibuya. This algorithm seems to be decisively better than any previous procedure. The sampling methods %r the normal distribution, W ~ . ~ presented in Section 4, display a ~der variety of ap-~3 proaci~es~ Nc single method can be co,~sidered optimaL Instead there is a choice between slower programs whicIb require li*tle core space and fk~ster rot~i~es ~[~a~ make ~+se of lengthy tables of coestams. The authors' primary conwiba~ion is the rise of polynomiaI sampling (as ex~ p/tiffed in Section 2)to eliminate any dependency on standard&ruction programs. All algorithms are described in the style of Knu~h {9I wb:h the ~ltowif~g two conve~tio~s: l, ~ Ge~'~erate :& (or fL ~ u ~°, etc.) signifies takir~g a sample ,~ from t:he tmiform distribution i~ ~he ope,~ ia~ ~erv~t ~x:~weee 0 a~d i, ~f several s~,~ch q~mn~i~:ies are g:¢f~era~ed the sampks are assumed to be #~depcndem " "Deliver v" always ret~:'rs ~o ~he final sample x from (~e target distrib{~tio. ~. A~'~ iramedia~e exit from ~he algorithm is implied after delivery.
Carbon quantum dots: synthesis, properties and applications

Carbon quantum dots (CQDs, C-dots or CDs), which are generally small carbon nanoparticles (less than 10 nm in size) with various unique properties, have found wide use in more and more fields during the last few years. In this feature article, we describe the recent progress in the field of CQDs, focusing on their synthetic methods, size control, modification strategies, photoelectric properties, luminescent mechanism, and applications in biomedicine, optronics, catalysis and sensor issues.
Extending Polyhedral Techniques towards Parallel Specifications and Approximations. (Extension des Techniques Polyedriques vers les Specifications Parallelles et les Approximations)

Polyhedral techniques enable the application of analysis and code transformations on multi-dimensional structures such as nested loops and arrays. They are usually restricted to sequential programs whose control is both affine and static. This thesis extend them to programs involving for example non-analyzable conditions or expressing parallelism. The first result is the extension of the analysis of live-ranges and memory conflicts, for scalar and arrays, to programs with parallel or approximated specification. In previous work on memory allocation for which this analysis is required, the concept of time provides a total order over the instructions and the existence of this order is an implicit requirement. We showed that it is possible to carry out such analysis on any partial order which match the parallelism of the studied program. The second result is to extend memory folding techniques, based on Euclidean lattices, to automatically find an appropriate basis from the set of memory conflicts. This set is often non convex, case that was inadequately handled by the previous methods. The last result applies both previous analyzes to "pipelined" blocking methods, especially in case of parametric block size. This situation gives rise to non-affine control but can be processed accurately by the choice of suitable approximations. This paves the way for efficient kernel offloading to accelerators such as GPUs, FPGAs or other dedicated circuit.
Tweet Ranking Based on Heterogeneous Networks

Ranking tweets is a fundamental task to make it easier to distill the vast amounts of information shared by users. In this paper, we explore the novel idea of ranking tweets on a topic using heterogeneous networks. We construct heterogeneous networks by harnessing cross-genre linkages between tweets and semantically-related web documents from formal genres, and inferring implicit links between tweets and users. To rank tweets effectively by capturing the semantics and importance of different linkages, we introduce Tri-HITS, a model to iteratively propagate ranking scores across heterogeneous networks. We show that integrating both formal genre and inferred social networks with tweet networks produces a higher-quality ranking than the tweet networks alone. 1 Title and Abstract in Chinese u
In Situ Pu isotopic measurements using electromechanically cooled HPGe detectors at PFPF

A high-resolution gamma ray spectroscopy (HRGS) system has been installed at the Advanced Material Accountancy Glovebox Assay (AMAGB) System so that neutron and gamma ray measurements can occur simultaneously on material transfer containers. This equipment was installed in August 2000 at the Plutonium Fucl Production Facility (PFPF) in Japan. It is anticipated that placing the HRG6 system at the neutron assay station will save a few person-days per IAEA inspection because it will no longer be necessary to take samples from the transfer container for isotopic analysis at another assay station. The HRGS system consists of a 25% relative efficiency coaxial detector with electromechanical cooling and digital signal processing. The digital spectrometer has the benefit of increasing throughput, improving energy resolution, and extending the lifetime of neutron damaged HPGe detectors as compared to analog spectrometers. The gamma-ray system is used to verify the Pu isotopic composition and {sup 241}Am concentration in transfer containers of MOX. The {sup 240}Pu{sub eff} action is calculated from the isotopic data and is used to convert the neutron assay data to total grams plutonium. The results of performance tests and calibration measurements using this system are reported in this paper.
A Mosaic Genetic Screen Reveals Distinct Roles for trithorax and Polycomb Group Genes in Drosophila Eye Development

The wave of differentiation that traverses the Drosophila eye disc requires rapid transitions in gene expression that are controlled by a number of signaling molecules also required in other developmental processes. We have used a mosaic genetic screen to systematically identify autosomal genes required for the normal pattern of photoreceptor differentiation, independent of their requirements for viability. In addition to genes known to be important for eye development and to known and novel components of the Hedgehog, Decapentaplegic, Wingless, Epidermal growth factor receptor, and Notch signaling pathways, we identified several members of the Polycomb and trithorax classes of genes encoding general transcriptional regulators. Mutations in these genes disrupt the transitions between zones along the anterior-posterior axis of the eye disc that express different combinations of transcription factors. Different trithorax group genes have very different mutant phenotypes, indicating that target genes differ in their requirements for chromatin remodeling, histone modification, and coactivation factors.
Improvement in the Corrosion Resistance of Zinc-plated Steel by Electrodeposition of Magnesium from a Molten Salt

Electrodeposition of magnesium on zinc-plated steel from a molten salt electrolyte was investigated in order to improve its corrosion resistance. The 55 mol%LiCl-39 mol%KCl-5 mol%MgCl2-1 mol%CsCl molten salt was used for the electrodeposition of magnesium on zinc-plated steel. The primary crystallization temperature of the salt is 574 K, which is 119 K lower than the melting point of zinc. The molten salt gave homogeneous electrodeposition of magnesium on a zinc-plated steel at 653 K. The magnesium electrodeposited diffused into the zinc layer of the zinc-plated steel during electrolysis. In 5 mass%NaCl aqueous solution at room temperature, the magnesium-deposited zinc-plated steel did not form red rust for 41 days whereas the zinc-plated steel formed red rust after 10 days. The red rust, which was formed at 41 days on the magnesium deposited zinc-plated steel, had localized for further 21 days without expanding. This fact suggests that the magnesium-deposited zinc-plated steel have a self healing ability. Moreover, in a salt spray test at 308 K, the time of generation of red rust for the magnesium-deposited zinc-plated steel was 10 times longer than for the conventional zinc-plated steel.
A Micromechanical Prediction of Initial Yield Surfaces of Unidirectional Composites

For two-phase materials composed of ductile matrices reinforced with plastically nondeformable inclusions, the yield condition that has the same form as Tsai and Wu's phenomenological criterion has been deduced through a micromechanics analysis. Basic assumptions made are that the matrix material obeys the Levy-von Mises flow rule, and that matrix plastic strains are uniform. In general, the shape of the yield surface can be proved to be hyperellipsoidal. A further analysis is devoted to the case where the inclusions can be treated as identical ellipsoids with corresponding axes aligned. Based on the results, numerical computation of yield strength parameters is carried out for unidirectional boron fiber-aluminum composites subjected to uniform temperature changes prior to external loading. It is shown that yielding cannot take place under certain combined triaxial (not hydrostatic) stresses. Some discussion related to the effect of prior temperature changes is also given.
MPSS: Mobile Proactive Secret Sharing

This article describes MPSS, a new way to do proactive secret sharing. MPSS provides mobility: The group of nodes holding the shares of the secret can change at each resharing, which is essential in a long-lived system. MPSS additionally allows the number of tolerated faulty shareholders to change when the secret is moved so that the system can tolerate more (or fewer) corruptions; this allows reconfiguration on-the-fly to accommodate changes in the environment. MPSS includes an efficient protocol that is intended to be used in practice. The protocol is optimized for the common case of no or few failures, but degradation when there are more failures is modest. MPSS contains a step in which nodes accuse proposals made by other nodes; we show a novel way to handle these accusations when their verity cannot be known. We also present a way to produce accusations that can be verified without releasing keys of other nodes; verifiable accusations improve the performance of MPSS, and are a useful primitive independent of MPSS.
Numerical Simulation of aWeakly NonlinearModel for Internal Waves

Internal waves arise in a wide array of oceanographic problems of both theoretical and engineering interest. In this contribution we present a new model, valid in the weakly nonlinear regime, for the propagation of disturbances along the interface between two ideal fluid layers of infinite extent and different densities. Additionally, we present a novel high-order/spectral algorithm for its accurate and stable simulation. Numerical validation results and simulations of wave-packet evolution are provided. AMS subject classifications: 76B07, 76B15, 76B55, 65M70
Sensitivity Analysis and Uncertainty Propagation in a General-Purpose Thermal Analysis Code

Methods are discussed for computing the sensitivity of field variables to changes in material properties and initial/boundary condition parameters for heat transfer problems. The method we focus on is termed the ''Sensitivity Equation Method'' (SEM). It involves deriving field equations for sensitivity coefficients by differentiating the original field equations with respect to the parameters of interest and numerically solving the resulting sensitivity field equations. Uncertainty in the model parameters are then propagated through the computational model using results derived from first-order perturbation theory; this technique is identical to the methodology typically used to propagate experimental uncertainty. Numerical results are presented for the design of an experiment to estimate the thermal conductivity of stainless steel using transient temperature measurements made on prototypical hardware of a companion contact conductance experiment. Comments are made relative to extending the SEM to conjugate heat transfer problems.
Haemodynamic changes in the second half of pregnancy: a longitudinal, noninvasive study with thoracic electrical bioimpedance

Objective Maternal cardiovascular adaptations to pregnancy are necessary for an adequate fetomaternal circulation. However, the time course of physiological haemodynamic changes during the second half of pregnancy remains unclear. Various methods, invasive and noninvasive, are described to measure these changes. The thoracic electrical bioimpedance (TEB) technique is a method which is especially suitable to measure haemodynamic changes over time. The aim of the study was to determine both individual and group trends of haemodynamic changes in healthy pregnant women during the second half of pregnancy by means of TEB. Outcome variables are heart rate (HR), stroke volume (SV), cardiac output (CO) and blood pressure.
Influence of fiber orientation on high stress wear behavior of sisal fiber-reinforced epoxy composites

Sisal fiber-reinforced epoxy composites having three different fiber orientations, namely LL, LT, TT mentioned in the text were prepared and tested for their high stress abrasive wear behavior. Effect of fiber orientation, sliding distance, and load on abrasive wear of sisal–epoxy composites have been determined. Wear data of composites have been compared with the pure epoxy. Incorporation of fibers decreases the wear rate of epoxy resin, which varies with the fiber orientation. Wear rate in case of TT composite is found minimum as compared to other two composites. Wear rate follows the following trend, WTT < WLT < WLL. Owing to minimum exposed area of fiber to the sliding asperities, lowest wear rate occurs in the case of TT composite. Increase of load and sliding distance increases the wear volume in all the composites, because of the progressive loss of material. Wear mechanism has been discussed by using SEM micrographs of the worn surfaces. POLYM. COMPOS. , 28:437–441, 2007. © 2007 Society of Plastics Engineers.
Electrical impedance tomography-based sensing skin for quantitative imaging of damage in concrete

This paper outlines the development of a large-area sensing skin for damage detection in concrete structures. The developed sensing skin consists of a thin layer of electrically conductive copper paint that is applied to the surface of the concrete. Cracking of the concrete substrate results in the rupture of the sensing skin, decreasing its electrical conductivity locally. The decrease in conductivity is detected with electrical impedance tomography (EIT) imaging. In previous works, electrically based sensing skins have provided only qualitative information on the damage on the substrate surface. In this paper, we study whether quantitative imaging of the damage is possible. We utilize application-specific models and computational methods in the image reconstruction, including a total variation (TV) prior model for the damage and an approximate correction of the modeling errors caused by the inhomogeneity of the painted sensing skin. The developed damage detection method is tested experimentally by applying the sensing skin to polymeric substrates and a reinforced concrete beam under four-point bending. In all test cases, the EIT-based sensing skin provides quantitative information on cracks and/or other damages on the substrate surface: featuring a very low conductivity in the damage locations, and a reliable indication of the lengths and shapes of the cracks. The results strongly support the applicability of the painted EIT-based sensing skin for damage detection in reinforced concrete elements and other substrates.