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When individuals are released from prison, they typically enter a period of post confinement community supervision. While under community supervision, their behaviors are subject to special conditions requiring them to report to supervisors and prohibiting certain behaviors such as drug and alcohol use. Many supervisees are returned to prison because they violate those special conditions, or because they commit minor crimes that would not result in prison were they not being supervised. But others are returned to prison for serious new crimes. We distinguish the two as nuisance behaviors (the former) and pernicious behaviors (the latter). Our research applies competing events survival analysis to distinguish a structural model that accounts for nuisance behaviors from a structural model that accounts for pernicious behaviors. We demonstrate that returning offenders to prison for technical violations and minor crimes may reduce the incidence of major crimes because the occurrence of nuisance behaviors and pernicious behaviors are highly correlated. Our findings support the theory that nuisance behaviors signal the likelihood of pernicious behaviors. [ABSTRACT FROM AUTHOR]

Particulate composites are considered here as multiphase composite in which the interfaces are imperfect. When the interface mechanical properties are those of a linear elastic material, the minimum of potential and complementary energy is used in order to obtain bounds of effective elastic modulus of the composite. Test displacements or stress fields are build and characterized using Green’s functions of a comparison homogeneous body, polarization fields and extension of the classical Lippmann–Schwinger equations. Then when spatial distribution of phases are known, in particular for isotropic distribution of phases or patterns, a generalization of Hashin–Shtrikman principle is obtained and lower and upper bounds are proposed.

Multistage mixed-integer distributionally robust optimization (DRO) forms a class of extremely challenging problems since their size grows exponentially with the number of stages. One way to model the uncertainty in multistage DRO is by creating sets of conditional distributions (the so-called conditional ambiguity sets) on a finite scenario tree and requiring that such distributions remain close to nominal conditional distributions according to some measure of similarity/distance (e.g., Φ-divergences or Wasserstein distance). In this paper, new bounding criteria for this class of difficult decision problems are provided through scenario grouping using the ambiguity sets associated with various commonly used Φ-divergences and the Wasserstein distance. Our approach does not require any special problem structure such as linearity, convexity, stagewise independence, and so forth. Therefore, while we focus on multistage mixed-integer DRO, our bounds can be applied to a wide range of DRO problems including two-stage and multistage, with or without integer variables, convex or nonconvex, and nested or nonnested formulations. Numerical results on a multistage mixed-integer production problem show the efficiency of the proposed approach through different choices of partition strategies, ambiguity sets, and levels of robustness. [ABSTRACT FROM AUTHOR]

This paper develops solution strategies for large-scale nonsmooth optimization problems. We transform nonsmooth programs into equivalent mathematical programs with complementarity constraints (MPCCs), and devise NLP-based strategies for their solution. For this purpose, two NLP formulations based on complementarity relaxations are put forward, one of which applies a parameterized formulation and operates with a bounding algorithm, with the aim of taking advantage of the NLP sensitivities in search for the solution; and the other relates closely to the well-studied Lin-Fukushima formulation. Relations between the solutions of these NLPs and of the MPCC is revealed by sensitivity analysis. With appropriate assumptions, the resulting solution of the NLP formulations are proved to be C- and M-stationary for the MPCCs in the limit. Numerical performance of the proposed formulations, and the formulations by Lin & Fukushima and by Scholtes are studied and compared, with selected examples from the MacMPEC collection and two large-scale distillation cases. [ABSTRACT FROM AUTHOR]

Some quadrupeds have evolved the ability of pronking, which consists in leaping by extending the four limbs simultaneously. Pronking is typically observed in some ungulate species inhabiting grassland populated by obstacles such as shrubs, rocks and fallen branches scattered across the environment. Several possible explanations have been proposed for this peculiar behaviour, including the honest signalling of the fitness of the individual to predators or the transmission of a warning alert to conspecifics, but so far none of them has been advocated as conclusive. In this work, we investigate the kinematics of pronking on a two-dimensional landscape populated by randomly scattered obstacles. We show that when the density of obstacles is larger than a critical threshold, pronking becomes the gait that maximizes the probability of trespassing in the shortest possible time all the obstacles distributed across the distance fled, and thus represents an effective escape strategy based on a simple open-loop control. The transition between pronking and more conventional gaits such as trotting and galloping occurs at a threshold obstacle density and is continuous for a non-increasing monotone distribution of the height of obstacles, and discrete when the distribution is peaked at a non-zero height. We discuss the implications of our results for the autonomous robotic exploration on unstructured terrain.

Objectives. The purpose of this study is to determine the associations between horizontal jump and sprint acceleration, as well as maximal speed performance. Methods. A systematic literature search was performed using PubMed, MEDLINE (EBSCOhost), and Web of Science. The studies that were included in this review must meet the following criteria: (1) well-trained individuals over the age of 18 years old; (2) Pearson's correlation coefficients between sprint time and horizontal jump distance were provided; (3) the sprint distance was limited to 0-100 m. The quality of the studies was assessed using a modified version of the Downs and Black Quality Index test. A random-effects model was used to determine the effect sizes, and heterogeneity between studies was examined using the Q statistic and I2. Results. From the identified 2,815 studies, 27 studies were included in this study (two from reference lists). The sprint time of the sprint acceleration phase was moderately and negatively correlated with the standing long jump (r D -0:45, z D 7:48, p < 0:001), single leg standing long jump (r D-0:48, z D3:49, p<0:001) and horizontal drop jump distance (r D-0:48, z D3:49, p<0:001), and was largely and negatively correlated with multiple jump distance (r D-0:69, z D6:02, p<0:001). Out of five studies assessed the standing triple jump, three studies reported significant positive association with the sprint acceleration performance. The sprint time of maximal speed phase was very largely and negatively associated with standing long jump distance (r D -0:73, z D 4:44, p < 0:001) and multiple jump distance (r D -0:76, z D 6:86, p<0:001). Conclusions. This review indicates the moderate to very large associations between horizontal jump and sprint acceleration and maximal speed performance, and the highest magnitude of associations between them is found in the multiple jump. Moreover, compared to the sprint acceleration performance, there are greater associations between maximal speed performance and standing long jump and multiple jump distance. [ABSTRACT FROM AUTHOR]

This study examines the effect of plyometric training on anaerobic capacities in skateboarding athletes. A total of 28 skateboarding athletes, 14 in the experimental group and 14 in the control group, between the ages of 14-18 participated in the research. As the experimental and control groups continued to practice skateboarding regularly, the experimental group had an extra 8 weeks and two days of plyometric training. Two measurements were taken before and after the workout (pretest). The data were obtained using the SPSS26 statistical package program. Since the number of participants is 28, the Data did not show a normal distribution. Wilkoxcan Test was used in the comparison of preliminary and final test in the group. The Man Whitney U test was used to compare the data between the groups and was accepted as a level of 0.05. The result was statistically compared between the test group and the control group, and it was determined that there was no significant difference between the vertical jump and anaerobic power parameters (p>0.05). When we compare the intra-group data of the experimental group and the control group, there is a statistically significant difference in the mean of vertical spatter and anaerobic power (p<0.05). As a result, a positive increase in vertical jump and anaerobic power parameters was determined after 8 weeks of plyometric training of the experimental group.It can be said that regularly planned and programmed 8-week plyometric training can contribute to the development of parameters such as vertical jump, anaerobic power, explosive strength in athletes. [ABSTRACT FROM AUTHOR]

We introduce a class of proper posets which is preserved under countable support iterations, includes ω ω -bounding, Cohen, Miller, and Mathias posets associated to filters with the Hurewicz covering properties, and has the property that the ground model reals remain splitting and unbounded in corresponding extensions. Our results may be considered as a possible path towards solving variations of the famous Roitman problem. [ABSTRACT FROM AUTHOR]

In this study, Hölder Exponent (HE), Variance (var) and densely populated range are measured to extract meaningful features from the high resolution (HR) images. These extracted features are considered here as the reduced representation of high resolution (HR) images. Five-layer simplified artificial neural network (ANN) architecture configured and trained using the reduced representation for building detection and counting in HR images. The scale and orientation of the movable window are changed to find an optimum bounding box of the buildings. The method is validated by applying on World View-2 pan-sharpened multispectral images having spatial resolution 0.46 m. In comparison with CNN and ResNet-18, the accuracy assessment result is quite promising (92%) with proposed method for detecting buildings in HR images. The proposed method, distinctly identified scale variant buildings and detected individual buildings even if they are in close proximity. [ABSTRACT FROM AUTHOR]

From a cognitive‑semantic perspective, two important conceptual schemas underlie determiner use and the count/mass distinction in languages such as English and French, namely bounding and definiteness. This paper investigates to what extent these concepts are related to noun phrase marking in Guianese French Creole (GFC). The corpus‑based analysis shows that GFC uses bare nouns not only with unbounded entities and in non‑referential and generic contexts, but also for representing singular and plural indefinite and definite referents. At the same time, GFC shows a clear count/mass distinction and also has definite and indefinite determiners. However, in contrast to article languages such as English and French, bounding and definiteness need to be examined alongside semantic‑pragmatic and discourse‑informational criteria in order to explain the use of determiners and bare nouns in GFC. Thus, determiner use as a grammatical individuation strategy clearly has a different weight in GFC, which does not fit into cross‑linguistic typologies of articleless and article languages (e.g. Chierchia 1998). The comparative results on GFC, French and English also serve to evaluate two recent typological claims: while they confirm Le Bruyn et al.’s (2017) hypothesis on a correlation between the richness of the article system and the freedom of bare noun use, Abraham et al.’s (2007) claim of a universally complementary distribution of articles and grammatical aspect distinctions in the verb phrase is not supported by the data.

This paper provides an analysis of the aspectual properties of deictic-presentative constructions headed by It. ecco and Fr. voici/voilà. It will be shown that even though deictic pointing elements do not constitute verbs, they exhibit verb-like characteristics in some regards. As is the case with certain tense forms, the use of these elements anchors the situation pointed out at the moment of speech and at the same time imposes a perspective of simultaneity, which presents it as temporally unbounded and thus imperfective. Furthermore, it will be demonstrated that, based on this temporal-aspectual profile, the different types of subconstructions headed by ecco and voilà also impose aspectual readings that go beyond this internal perspective by highlighting events such as resultative states or inchoative events.

We consider a Markovian multiserver queueing system with two customer classes, preemptive priorities, and reneging. We formulate this system as an infinite level-dependent quasi-birth-death process (LDQBD). We introduce an algorithm that endogenously truncates the level and calculates lower and upper bounds on stationary probabilities of this LDQBD such that the gap between the bounds can be any desired amount. Our algorithm can be applied to any LDQBD for which the rate matrices become elementwise nonincreasing above some level. This appears to be the first algorithm that provides bounds on stationary probabilities for an infinite-level LDQBD. To obtain these bounds, the algorithm first obtains lower and upper bounds on the rate matrices of the LDQBD using a novel method, which can be applied to any LDQBD. We then extend this algorithm to approximate performance measures of the system of interest and calculate exact lower and upper bounds for those that can be expressed as probabilities, such as the probability that an incoming low-priority customer will wait. We generate a wide range of instances with up to 100 servers and compare the solution times and accuracy of our algorithm with two existing algorithms. These numerical experiments indicate that our algorithm is faster than the other two algorithms for a given accuracy requirement. We investigate the impact of changing service rates on the proportion of low-priority customers served and their wait time, and we demonstrate how ignoring one of these measures can possibly mislead decision makers. Summary of Contribution: We contribute to operations research by modeling a practically important queueing system and developing an algorithm to accurately compute performance measures for that system. We also contribute to computer science by providing error and complexity analysis for the algorithm to solve a broad class of two-dimensional Markov chains with infinite state space. [ABSTRACT FROM AUTHOR]

Statisticians have developed propensity score methods to improve generalizations from studies that do not employ random sampling. However, these methods rely on assumptions whose plausibility may be questionable. We introduce and discuss bounding, an approach that is based on alternative assumptions that may be more plausible. The bounding framework nonparametrically estimates population parameters using a range of plausible values. We illustrate how to tighten bounds using three approaches: imposing a monotonicity assumption, redefining the population of inference, and using propensity score stratification. Using two simulation studies, we examine the conditions under which bounds are tightened. We conclude with an application of bounding to SimCalc, a cluster randomized trial that evaluated the effectiveness of a technology aid on mathematics achievement. [ABSTRACT FROM AUTHOR]

Post-Activation Potentiation (PAP) is a phenomenon which can improve power performance executed after a previous conditioning activity. PAP is usually evoked through heavy resistance or plyometric exercise. It has been suggested to refer to as Postactivation Performance Enhancement (PAPE) when research is field-based on explosive activities. To our best knowledge, no studies have investigated the effects of PAPE on deceleration performance, which is a key factor in sports involving change of directions. Therefore, the aim of this study was to investigate the influence of a plyometric exercise protocol on a subsequent deceleration running performance. University soccer players (n = 18) performed seven deceleration trials and were assessed at baseline and after ~15 s, 2, 4, 8, 12 and 16 min either following a walking control condition (C) or three sets of ten repetitions of alternate-leg bounding (plyometric, P). Results showed no significant differences at any of the trials under the control condition (C) in comparison to the relative baseline. Under the plyometric condition (P), deceleration performance executed two minutes after the plyometric activity resulted in significantly faster results compared to the baseline values (p = 0.042; ES = 0.86, large effect; % of improvement = 4.13 %). The main findings are that plyometric exercise improves a subsequent running deceleration performance, 2 min after its execution. Future investigations should focus on more complex actions such as changes of direction and agility. [ABSTRACT FROM AUTHOR]

In this article I make use of the concept of bounding developed within cognitive grammar, initially devised by Ronald Langacker (1983). I examine how the arrangement of nouns denoting bounded or unbounded entities relates to the imagery of two contrastive worlds in Zuzanna Ginczanka’s poem Dziewictwo (Virginity). The accurate rendition of Ginczanka’s grammatical choices in this regard will be the central criterion for the linguistic evaluation of the Ukrainian translation of the poem.

This article explores the experiences of young Syrian refugees in the UK. It looks at how settlement plays out for two 'types' of Syrian refugees, those resettled by the UK Government and those who claim asylum in the UK. Drawing on new empirical data from 484 Syrian refugees in the UK, the article compares and contrasts the two groups' access to educational provisions, the labour market and general support mechanisms that should, in principle, be equally available to all refugees. This reveals the scale and consequences of the existing two-tier system of international protection based entirely on how refugees come to be in the UK, rather than any objective analysis of their reason for flight. In doing so, the article seeks to contribute to debates about the process and implications of how host states label people, in this case by de facto treating resettled Syrians as the 'good' refugees, while those who arrive of their own volition, regardless of their needs, are viewed as more problematic. [ABSTRACT FROM AUTHOR]

This article examines the problem of balancing modern assembly lines for large-size products typical for the automotive industry. The model of a multimanned assembly line balancing problem is proposed, in which assembly tasks are assigned to specific areas closely related to the place of the performance thereof on the vehicle. The model takes into account additional location restrictions. The proposed approach fits in with current trends aiming at minimizing the space occupied by assembly lines along with reducing the number of stations. A hybrid method is proposed combining modified known heuristics of task assignments to workstations with bounding and backtracking techniques in order to determine the assignment of workers to tasks. [ABSTRACT FROM AUTHOR]

This short paper describes a simple subgradient-based techniques for deriving bounds on the optimal solution value when using the ADMM to solve convex optimization problems. The technique requires a bound on the magnitude of some optimal solution vector, but is otherwise completely general. Some computational examples using LASSO problems demonstrate that the technique can produce steadily converging bounds in situations in which standard Lagrangian bounds yield little or no useful information. A second set of experiments establishes a proof of concept indicating the potential practical usefulness of the bounding technique. [ABSTRACT FROM AUTHOR]

This paper estimates the effects of teenage childbearing on education, working, physical and mental health, and physical activity of young girls in Mexico using two waves of the nationally representative Mexican Family Life Survey. We employ a propensity score matching model that accounts for a rich set of baseline covariates that predict teenage childbearing to attempt to reduce the bias due to confounding variables associated with teenage childbearing. The results demonstrate that teenage childbearing is associated with an increase in the probability of being overweight, and reductions in physical activity and the probability of high school completion. Moreover, the results are consistent when we employ sibling fixed effects to account for unobservable family background. [ABSTRACT FROM AUTHOR]

In this article I make use of the concept of bounding developed within cognitive grammar, initially devised by Ronald Langacker (1983). I examine how the arrangement of nouns denoting bounded or unbounded entities relates to the imagery of two contrastive worlds in Zuzanna Ginczanka's poem Dziewictwo (Virginity). The accurate rendition of Ginczanka's grammatical choices in this regard will be the central criterion for the linguistic evaluation of the Ukrainian translation of the poem. [ABSTRACT FROM AUTHOR]

We continue to investigate the notion of I K ${\mathcal I}^{\mathcal K}$ -convergence (which concerns with the convergence with respect to one ideal along a set which is "big" with respect to another ideal) introduced by M. Mačaj and M. Sleziak [10] with primary focus on sequences of real functions. Our investigation is based on results by R. Filipów and M. Staniszewski [5-6] or M. Staniszewski [11]. [ABSTRACT FROM AUTHOR]

This study was undertaken to compare force-time characteristics, muscle power, and electromyographic (EMG) activities of the leg muscles in maximal sprinting and in selected bounding and jumping exercises. Seven male sprinters performed maximal bounding (MB), maximal stepping (MS), maximal hopping with the right (MHR) and left (MHL) legs, and maximal sprint running (MR). These "horizontal" exercises and running were performed on a force platform. EMG activity was telemetered unilaterally from five leg muscles during each trial. The results indicated significant (p < .001) differences among the studied exercises in velocity, stride length, stride rate, flight time, and contact time. Also, significant differences were noticed in reactive forces (p < .01-.001) and power (p lt; .01) among the performances, whereas only insignificant differences were observed in EMG patterns. The average resultant forces during the braking and propulsion phases in MS, MHR, and MHL were greater (p lt; .001) than in MR and MB. Stepping and hopping are cyclic and sprint-specific and may be used as strength exercises for sprinters because of great strength demand. [ABSTRACT FROM AUTHOR]

Abstract In accordance with the “Liquefaction Experiments and Analysis Projects (LEAP)” guidelines, class-A, B and C predictions are performed for the response of centrifuge tests on a sloped configuration of Ottawa-F65 soil in a rigid container. The objective of this paper is to discuss important aspects on the calibration process of a pressure-dependent bounding surface constitutive model for the simulation of centrifuge experiments. The constitutive model used in this study is based on the theory of Critical State Soil Mechanics that has shown to be suitable to represent the behavior of cohesionless soils. Results of class-A predictions match experiment data reasonably well. An attempt is made to find a single set of material parameters to be used for class-B and class-C prediction of all six centrifuge tests. Highlights • Details of a finite element model used for simulating centrifuge test are given. • Results of class-A, B and C prediction on centrifuge tests are presented and discussed. • Discussion on calibration of a constitutive model is given. • Finding a single set of representative material parameter to be used in simulation of different centrifuge experiments is found to be impractical. [ABSTRACT FROM AUTHOR]

Abstract Animals, including humans, have been shown to maintain a gait during locomotion that minimizes the risk of injury and energetic cost. Despite the importance of understanding the mechanisms of gait regulation, ethical and experimental challenges have prevented full exploration of these. Here we present data on the gait response of mice to rapid, precisely timed, spatially confined mechanical perturbations. Our data elucidate that after the mechanical perturbation, the mouse gait response is anisotropic, preferring deviations away from the trot towards bounding, over those towards other gaits, such as walk or pace. We quantified this shift by projecting the observed gait onto the line between trot and bound, in the space of quadrupedal gaits. We call this projection λ. For λ = 0 , the gait is the ideal trot; for λ = ± π , it is the ideal bound. We found that the substrate perturbation caused a significant shift in λ towards bound during the stride in which the perturbation occurred and the following stride (linear mixed effects model: Δ λ = 0.26 ± 0.07 and Δ λ = 0.21 ± 0.07 , respectively; random effect for animal, p < 0.05 for both strides, n = 8 mice). We hypothesize that this is because the bounding gait is better suited to rapid acceleration or deceleration, and an exploratory analysis of jerk showed that it was significantly correlated with λ (p < 0.05). Understanding how gait is controlled under perturbations can aid in diagnosing gait pathologies and in the design of more agile robots. [ABSTRACT FROM AUTHOR]

Abstract: Intermittent flight through flap‐gliding (alternating flapping phases and gliding phases with spread wings) or bounding (flapping and ballistic phases with wings folded against the body) are strategies to optimize aerial efficiency which are commonly used among small birds today. The broad morphological disparity of Mesozoic birds suggests that a range of aerial strategies could have evolved early in avian evolution. Based on biomechanics and aerodynamic theory, this study reconstructs the flight modes of two small enantiornithines from the Lower Cretaceous fossil site of Las Hoyas (Spain): Concornis lacustris and Eoalulavis hoyasi. Our results show that the short length of their wings in relation to their body masses were suitable for flying through strict flapping and intermittent bounds, but not through facultative glides. Aerodynamic models indicate that the power margins of these birds were sufficient to sustain bounding flight. Our results thus suggest that C. lacustris and E. hoyasi would have increased aerial efficiency through bounding flight, just as many small passerines and woodpeckers do today. Intermittent bounding appears to have evolved early in the evolutionary history of birds, at least 126 million years ago. [ABSTRACT FROM AUTHOR]

In the paper, the authors present an explicit form for a family of inhomoge- neous linear ordinary differential equations, find a more significant expression for all derivatives of a function related to the solution to the family of inhomo- geneous linear ordinary differential equations in terms of the Lerch transcen- dent, establish an explicit formula for computing all derivatives of the solution to the family of inhomogeneous linear ordinary differential equations, acquire the absolute monotonicity, complete monotonicity, the Bernstein function property of several functions related to the solution to the family of inhomo- geneous linear ordinary differential equations, discover a diagonal recurrence relation of the Stirling numbers of the first kind, and derive an inequality for bounding the logarithmic function. [ABSTRACT FROM AUTHOR]

Translation and bend of the spine in the sagittal plane during high-speed quadruped running were investigated. The effect of the two spine motions on slip between the foot and the ground was also explored. First, three simplified sagittal plane models of quadruped mammals were studied in symmetric bounding. The first model’s trunk allowed no relative motion, the second model allowed only trunk bend, and the third model allowed both bend and translation. Next, torque was introduced to equivalently replace spine motion and the possibility of foot slip of the three models was analyzed theoretically. The results indicate that the third model has the least possibility of slip. This conclusion was further confirmed by simulation experiments. Finally, the conclusion was verified by the reductive model crawling robot. [ABSTRACT FROM AUTHOR]

Fall detection for aging people is still a mainstream research focus for the current aging society. Tools that are simple and inexpensive but have high accuracy rates are needed. RGB-D information retrieved from a home entertainment system was used to detect falls using typical bounding boxes techniques. These techniques have limitations. This research introduced the Adaptive Directional Bounding Box that made use of a comprehensive bounding box and a dynamic state machine in a new way to detect falls. The proposed approach offered a way to track and analyze continuous data streams of the visual images to automatically predict a fall event prior to the fall state in a single-phase instead of the typical two-phases. This can significantly affect the survival or severe injury of the elderly. The proposed method can improve accuracy by 25.5% and the response time by 21.31% on average as compared to existing approaches. [ABSTRACT FROM AUTHOR]

Haptics applications such as surgery simulations require collision detections that are more precise than others. An efficient collision detection method based on the clustering of bounding spheres was proposed in our prior study. This paper analyzes and compares the applied effects of the five most common subdivision surface methods on some 3D models for haptic collision detection. The five methods are Butterfly, Catmull-Clark, Mid-point, Loop, and LS3 (Least Squares Subdivision Surface). After performing a number of experiments, we have concluded that LS3 method is the most appropriate for haptic simulations. The more we applied surface subdivision, the more the collision detection results became precise. However, it is observed that the performance becomes better until a certain threshold and degrades afterward. In order to reduce the performance degradation, we adopted our prior work, which was the fast and precise collision detection method based on adaptive clustering. As a result, we obtained a notable improvement of the speed of collision detection. [ABSTRACT FROM AUTHOR]

Many dynamic decision problems involving uncertainty can be appropriately modeled as multistage stochastic programs. However, most practical instances are so large and/or complex that it is impossible to solve them on a single computer, especially due to memory limitations. Extending the work of [B. Sandikci, N. Kong, and A. J. Schaefer, Math. Program., 138 (2013), pp. 253{272] on two-stage stochastic mixed-integer programs, this paper considers general multistage stochastic programs and develops a bounding method based on scenario decomposition. This method is broadly applicable, as it does not assume any problem structure including convexity. Moreover, it naturally fits into a distributed computing environment. Computational experiments with large-scale instances (with up to 100 million scenarios, about 1.5 billion decision variables—85% binary—and 800 million constraints) demonstrate that the proposed method scales nicely with problem size and has immense potential to obtain high-quality solutions to practical instances within a reasonable time frame. [ABSTRACT FROM AUTHOR]

The contribution of the shape information of the underlying distribution in probability bounding problem is investigated and a linear programming based bounding methodology to obtain robust and efficiently computable bounds for the probability that at least k -out-of- n events occur is developed. The dual feasible basis structures of the relaxed versions of linear programs involved are fully described. The bounds for the probability that at least k -out-of- n events occur are obtained in the form of formulas and as the customized algorithmic solutions of the LP’s formulated. An application in finance is presented. [ABSTRACT FROM AUTHOR]

An anisotropic time-dependent bounding surface model for clays is developed by generalizing a previous time-independent model that adopts a flexible bounding surface. It is based on the framework for coupled elastoplasticity-viscoplasticity for clays and Perzyna's overstress theory. Three viscoplastic parameters were introduced and explained in detail. The model was validated against undrained creep tests for both isotropically and anisotropically consolidated clays, undrained and drained stress relaxation tests on some undisturbed clays, and undrained triaxial tests with varying strain rates on natural Hong Kong marine deposit clay. The general agreement between the model simulations and test results was satisfactory. The varying effects of lower-level parameters were discussed on the undrained multistage stress relaxation response for normally consolidated soils which had been ignored in literature. The flexibility of the model in capturing the shear strengths, which is the unique feature of the current model, was shown in the simulations of time-dependent triaxial tests on Taipei silty clay. All the simulations show that the proposed model is a relatively practical model considering both anisotropy and time dependency of clays. [ABSTRACT FROM AUTHOR]

The paper presents a critical state bounding surface constitutive model for describing the behaviour of overconsolidated clays for a wide range of overconsolidation ratios, called the Hardening State Parameter – HASP model. Keeping the simplicity and the same set of the parameters as Modified Cam Clay, the HASP model provides a more realistic description of numerous elements of clay behaviour. With the new state parameter formulation of the hardening rule, elasto-plastic behaviour is enabled from early stages of loading. In undrained conditions, general shape of effective stress paths for various overconsolidation ratios and negative pore pressure is well predicted. In drained conditions, strain hardening, strain softening, as well as smooth transition from contractive to dilatant behaviour before the peak strength is reached are described. Verification is done against published results of drained and undrained tests in triaxial compression and extension, on the samples with various overconsolidation ratios. [ABSTRACT FROM AUTHOR]

This study considered whether faults bounding hydrocarbon-bearing basins could be conduits for methane release to the atmosphere. Five basin bounding faults in the UK were considered: two which bounded potential shale gas basins; two faults that bounded coal basins; and one that bounded a basin with no known hydrocarbon deposits. In each basin, two mobile methane surveys were conducted, one along the surface expression of the basin bounding fault and one along a line of similar length but not intersecting the fault. All survey data was corrected for wind direction, the ambient CH 4 concentration and the distance to the possible source. The survey design allowed for Analysis of Variance and this showed that there was a significant difference between the fault and control survey lines though a significant flux from the fault was not found in all basins and there was no apparent link to the presence, or absence, of hydrocarbons. As such, shale basins did not have a significantly different CH 4 flux to non-shale hydrocarbon basins and non-hydrocarbon basins. These results could have implications for CH 4 emissions from faults both in the UK and globally. Including all the corrected fault data, we estimate faults have an emissions factor of 11.5 ± 6.3 t CH 4 /km/yr, while the most conservative estimate of the flux from faults is 0.7 ± 0.3 t CH 4 /km/yr. The use of isotopes meant that at least one site of thermogenic flux from a fault could be identified. However, the total length of faults that penetrate through-basins and go from the surface to hydrocarbon reservoirs at depth in the UK is not known; as such, the emissions factor could not be multiplied by an activity level to estimate a total UK CH 4 flux. [ABSTRACT FROM AUTHOR]

The article discusses the influence of plyometric training and high velocity movements with rapid succession and lengthening muscle contraction in jump training. It explains that explosive speed training enhances muscle conduction velocity and an indicator of neuromuscular performance linked with sprint speed. It is recommended for team sports like basketball and volleyball that require sequences of short explosive efforts and short sprints.

Investigating the effects of the Equatorial Ionization Anomaly (EIA) ionosphere and space weather on Global Navigation Satellite Systems (GNSS) is very crucial, and a key to successful implementation of a GNSS augmentation system (SBAS) over the equatorial and low-latitude regions. A possible ionospheric vertical delay (GIVD, Grid Ionospheric Vertical Delay) broadcast at a Ionospheric Grid Point (IGP) and its confidence bounds errors (GIVE, Grid Ionospheric Vertical Error) are analyzed and compared with the ionospheric vertical delay estimated at a nearby user location over the West African Sub-Saharan region. Since African sub-Saharan ionosphere falls within the EIA region, which is always characterized by a disturbance in form of irregularities after sunset, and the disturbance is even more during the geomagnetically quiet conditions unlike middle latitudes, the need to have a reliable ionospheric threat model to cater for the nighttime ionospheric plasma irregularities for the future SBAS user is essential. The study was done during the most quiet and disturbed geomagnetic conditions on October 2013. A specific low latitude EGNOS-like algorithm, based on single thin layer model, was engaged to simulate SBAS message in the study. Our preliminary results indicate that, the estimated GIVE detects and protects a potential SBAS user against sampled ionospheric plasma irregularities over the region with a steep increment in GIVE to non-monitored after local sunset to post midnight. This corresponds to the onset of the usual ionospheric plasma irregularities in the region. The results further confirm that the effects of the geomagnetic storms on the ionosphere are not consistent in affecting GNSS applications over the region. Finally, this paper suggests further work to be investigated in order to improve the threat integrity model activity, and thereby enhance the availability of the future SBAS over African sub-Saharan region. [ABSTRACT FROM AUTHOR]

In this paper, we study a project scheduling problem that is called resource constrained project scheduling problem under minimization of total weighted resource tardiness penalty cost (RCPSP-TWRTPC). In this problem, the project is subject to renewable resources, each renewable resource is available for limited time periods during the project life cycle, and keeping the resource for each extra period results in some tardiness penalty cost. We introduce a branch and bound algorithm to solve the problem exactly and use several bounding, fathoming, and dominance rules in our algorithm to shorten the enumeration process. We point out parameters affecting the RCPSP-TWRTPC degree of difficulty, generate extensive sets of sample instances for the problem, and perform comprehensive experimental analysis using the customized algorithm and also CPLEX solver. We analyze the algorithm behavior with respect to the changes in instances degree of difficulty and compare its performance for different cases with the CPLEX solver. The results reveal algorithm efficiency. [ABSTRACT FROM AUTHOR]

For a locally finite set S in the hyperbolic plane, suppose C is a compact, n-edged two-cell of the centered dual complex of S, a coarsening of the Delaunay tessellation introduced in the author's prior work. We describe an effectively computable lower bound for the area of C, given an n-tuple of positive real numbers bounding its side lengths below, and for n ≤ 9 implement an algorithm to compute this bound. For geometrically reasonable side-length bounds, we expect the area bound to be sharp or near-sharp. [ABSTRACT FROM AUTHOR]

Particle breakage has a great influence on stress-strain behaviors of rockfill materials. A new relative breakage was proposed for rockfill materials. A critical state line incorporating particle breakage was termed as a breakage critical state line (BCSL). It was found that the BCSL position of rockfill materials pertained to the relative breakage. An elastoplastic model considering state dependence and particle breakage was proposed for rockfill materials. The effect of particle breakage was incorporated into the proposed state parameter, dilatancy stress ratio, stress dilatancy relation, bounding stress ratio, and plastic modulus in the proposed model. The model considering particle breakage can well predict the stress-strain and particle-breakage behaviors of rockfill materials at various confining pressures. [ABSTRACT FROM AUTHOR]

This paper proposes a constitutive model for cement-admixed soil based on the concept that the effect of cementitious bonding can be accounted for by incorporating a cohesion terminto the Cam-clay flow rule. The cohesion is not a constant; instead, it is allowed to decrease during loading to simulate the loss of bonding. The loss of bonding during loading is assumed to be related to the plastic work done against the structure. In other words, yielding and postyield behavior are mechanistically rather than phenomenologically based. This allows the shape of the yield surface to evolve from a nonelliptical shape to an elliptical shape as cohesion is lost during loading. Comparison with experimental results of undrained triaxial shearing tests over a range of mix proportions and confining pressures shows that the behavior of undrained specimens is well represented. Comparison with experimental results of drained triaxial shearing tests shows that the behavior of drained specimens is well represented up to the peak strength. The gradual yielding up to the defined initial yield point can also be captured by introducing a bounding surface. [ABSTRACT FROM AUTHOR]

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In this article we introduce new possibilities of bounding the stability constants that play a vital role in the reduced basis method. By bounding stability constants over a neighborhood we make it possible to guarantee stability at more than a finite number of points and to do that in the offline stage. We additionally show that Lyapunov stability of dynamical systems can be handled in the same framework. [ABSTRACT FROM AUTHOR]