7,149 research outputs found
Predicting Human Lifespan Limits
Recent discoveries show steady improvements in life expectancy during modern
decades. Does this support that humans continue to live longer in future? We
recently put forward the maximum survival tendency, as found in survival curves
of industrialized countries, which is described by extended Weibull model with
age-dependent stretched exponent. The maximum survival tendency suggests that
human survival dynamics may possess its intrinsic limit, beyond which survival
is inevitably forbidden. Based on such tendency, we develop the model and
explore the patterns in the maximum lifespan limits from industrialized
countries during recent three decades. This analysis strategy is simple and
useful to interpret the complicated human survival dynamics.Comment: 11 pages, 3 figures, 2 tables; Natural Science (in press
Decompositions of factor codes and embeddings between shift spaces with unequal entropies
Given a factor code between sofic shifts X and Y, there is a family of
decompositions of the original code into factor codes such that the entropies
of the intermediate subshifts arising from the decompositions are dense in the
interval from the entropy of Y to that of X. Furthermore, if X is of finite
type, we can choose those intermediate subshifts as shifts of finite type. In
the second part of the paper, given an embedding from a shift space to an
irreducible sofic shift, we characterize the set of the entropies of the
intermediate subshifts arising from the decompositions of the given embedding
into embeddings.Comment: 14pages, 2 figures; v2) minor revision. to appear in Ergodic Theory
Dynamical System
Beyond the Hashtags and Slogans: The Role of AAPIs in Police Reform
This report explores the responsibility AAPI communities have to participate in meaningful police reform. Je Yon Jung, a civil rights attorney with an extensive background in police misconduct cases, authored the brief. It delves into the history of policing, its roots in slavery and how systemic discrimination impacts the criminal justice system, from what happens in courtrooms to police practices and oversized law enforcement budgets. Grounded in data, facts, and stories, Jung examines police shooting fatalities, demystifies the "defund the police" movement, and provides examples of how AAPIs are not immune to police violence
Centroidal Momentum Analysis for Defining a Stability Index for Human-Exoskeleton Interactive Walking : Perturbation Detection in Human Gait
Recently, exoskeletons have been in the spotlight as many studies demonstrated the effectiveness of the exoskeletons as a means that enables to not only resolve long-standing issues such as increase of societal burden for the care of ageing populations but also augments productivity in several fields, such as rehabilitation and industrial fields. In particular, lower limb exoskeletons have attracted the medical field, especially related to the ageing society due to its impact on augmentation and recovery of walking capability which is one of the core determinants of independent daily living. For practical use of the lower limb exoskeletons in real environments, however, there are still several issues to be resolved. One of them is how to manage balance of human walking supported by the exoskeleton, in other words, how to monitor walking stability of a system combined with human and exoskeleton and maintain (or recover) the system balance when the user meets unpredicted disturbances, and thus to avoid falls.
The former is a rationale of the study and this paper deals with a ‘stability index’, referred to as a kind of measure to monitor the actual (in)stability state during walking. The proposed stability index is based on the Centroidal Momentum (CM) that consists of linear and angular momenta at the Center of Mass (CoM). CM is a fundamental parameter used to describe physical motion of a system in classical mechanics, and it has been studied widely in biomechanics and bipedal robot fields over the last decade as it, specifically angular momentum-based analysis, offers important clues on how humans maintain balance during walking as well as facilitates postural balance control of humanoid robots in standing.
As an extension of this context, in our previous work, we analyzed CM behavior during human walking under perturbations, specifically lateral perturbations applied to the pelvis. As a continuation of the study, in this paper, we examine whether CM could be used as the stability index to detect the perturbations as well as an initial loss of balance. In other words, a perturbation detection method on the basis of calculation of CM while waking is presented. In the method, variation of CM patterns between unperturbed and perturbed walking plays a crucial role in detecting perturbations. The method has been evaluated with experimental data of human walking and results show that the method is capable of detecting moderate and strong perturbations determined by combination of diverse durations and magnitudes of disturbance force. Average detection time obtained was about 334 msec.
This study was carried out in the context of the EU FP7 project BALANCE that aims at supporting the function of maintaining postural balance directly through a leg exoskeleton. For this purpose CM-based stability index to be developed and related findings will be extended to the exoskeleton cooperating with a human and assessed on performance inEuropean Commission FP
Some Grüss' Type Inequalities in 2-Inner Product Spaces and Applications for Determinantal Integral Inequalities
Some new Grüss type inequalities in 2-inner product spaces are given. Using this framework, some determinantal integral inequalities for synchronous functions are also derived
Single inorganic–organic hybrid nanowires with ambipolar photoresponse
We report for the first time single nanowires (NWs) with ambipolar (positive/negative) photoresponse that changes sign depending on the illumination wavelength. The single NWs were grown by the meniscus-guided method using inorganic (ZnO nanoparticles)–organic (PEDOT:PSS) hybrid materials. The ambipolar photoresponse of the single NWs enabled us to develop an unprecedented spectrum-discriminating NW photodetector array
Natural Language Processing with Assemblies of Neurons
The Assembly Calculus is a novel framework intended to bridge the gap between the level of neuron and synapses, and that of cognition. The Assembly Calculus is a computational system entailing a basic data item called an assembly, a stable set of neurons explained below; a set of operations that create and manipulate assemblies; and an execution model which is squarely based on basic tenets of neuroscience. Importantly, it allows the creation of biologically plausible, flexible and interpretable programs, enabling one to develop tangible hypotheses on how specific brain functions may work. Here, to help lay groundwork for the creation of algorithms in this framework, we present a natural language processing algorithm to solve the analogy task. Further, to facilitate such experimentation, we present here a tool which in real-time allows the simulation, modification and visualisation of this computational system, including several prepared examples. Lastly, we also present empirical analysis of the capabilities of the assembly calculus to store information in brain areas.Undergraduat
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