Improving the design of squat machine using motion capture and virtual prototyping

Dynamic squat is one of the most executed fitness exercise. Its use is widespread both for rehabilitation and training purposes. Several typologies of the squat exercise can be performed. The most important are the front squat and the back squat. In the front squat the barbell is held in front of the body across the clavicles and deltoids, while in the back squat exercise the bar is held on the back of the body at the base of the neck. In this paper we will refer to dynamic back squat. The squat exercise can be performed with or without the help of a machine that has the scope of guiding the person during the movement and ensuring his stability and safety. The use of this type of machine is often necessary when the workout is heavy and the risk of incorrect exercise and injuries is high. On the other hand, the rigid structure of this device often overconstrains the lifting movement. From all these observations, the purpose of the paper is to discuss an alternative design of a mechanism able to maintain the advantage to allow a free-body execution and to preserve the safety of the athletes as well. The proposed mechanism has been designed starting from an anthropometric study on the squat movement. This has been performed by using a motion capture system and applying computer-aided engineering techniques. The design activity started from the experimental investigation of the trajectory of the barbell during the natural execution of the unrestricted back squat exercise. The tests have been performed on several subjects with different mass, anthropometry and gender. In a second phase, the data have been processed and analyzed and a specific mechanism, able to reproduce the natural trajectories, has been synthetized. Finally, the design and optimization of the entire structure has been performed through the use of virtual prototyping techniques.     

A philosophical and evolutionary approach to cyber-bullying: social networks and the disruption of sub-moralities

Cyber-bullying, and other issues related to violence being committed online in prosocial environments, are beginning to constitute an emergency worldwide. Institutions are particularly sensitive to the problem especially as far as teenagers are concerned inasmuch as, in cases of inter-teen episodes, the deterrent power of ordinary justice (i.e. threaten to sue) is not as effective as it is between adults. In order to develop the most suitable policies, institution should not be satisfied with statistics and sociological perspectives on the phenomenon, but rather seek a deep ethical understanding—also referring to the biological and evolutionary past of human beings. The aim of this paper is to show a way to fill this theoretical gap, offering some answers (and some questions too) that can illuminate future policy-oriented research and reflection. In order to do so, we will start by connecting our argument to evolutionary studies carried out in the past two decades, focusing on gossip as a tool for social assortment, thus endowed with a dual function: protect the group from free riders, intruders and bullies but also bully the deviant members. In the “Mediating gossip through social networks” section, we will see which aspects of gossip, vital for bullying, are co-opted by social network scenarios. A fundamental trait of human social life, that is the subdivision in smaller coalitions, or sub-groups, will be shown as missing in social networks (SN) dynamics—therefore constituting themselves as structurally violent. The “Why and how do social networks empower bullying?” section will deal with techno-ethical and epistemological concerns regarding how gossip, mediated by SN, manages to empower cyber-bullying. The “Self-gossip and self-mobbing in the light of the disruption of sub-moralities” section will characterize cyber-bullying as often sparked by self-gossip (soon degrading into self-mobbing) in a scenario where familiar sub-groups, which also mediate defense and mutual understanding, are disrupted. The “Discussion and conclusion” section will consist of a philosophical summary, divided in two parts: a pars destruens analyzing whether SN, in their actual configurations, are fit for being used by humans-like-us, and a pars construens examining the broad potential consequences of highly enforced regulation aimed at contrasting cyber-bullying.     

The labour market effects of Alma Mater: Evidence from Italy

We use data from a nationally representative survey of Italian graduates to study whether Alma Mater matters for employment and earnings 3 years after graduation. We find that the attended college matters, and that there are important college-related differences, both among and within regions of the country. These differences, however, do not persist over time and are not large enough to trigger substantial mobility flows from poorly performing to better performing institutions. We also find evidence that going to a private university pays off at least in the early part of a career. Only part of this gain can be explained by the fact that private universities have lower pupil–teacher ratios than public institutions.     

Alternate Media and Cable

William R. Stround's Selected Bibliography on Telecommunications will now be available in an updated format from the Wisconsin Library Association, c/o Madison Public Library, 201 W. Mifflin Street, Madison, Wisc. 53703, for $1.50.

Lorenzo Milam, Sex in Broadcasting: A Handbook on Starting Community Radio Stations (Los Gatos, Calif.: Dildo Press, 1972 – $2.00, paper)

The Radio Times (5 University Ave., Los Gatos, Calif. 950-30, monthly, $20.00)

Alternate Radio Exchange (Box 852, Felton, Ca. 95018, published roughly every three weeks "more or less often as information available permits." $10.00 for a year with free ad service, or $5.00 per five months with no ad service.)     

Ball possession effectiveness in men's and women's elite basketball according to situational variables in different game periods

Abstract

The aim of the present study was to identify the importance of basketball performance indicators in predicting the effectiveness of ball possessions in men's and women's basketball, when controlling for situational variables and game periods. The sample consisted of 7234 ball possessions, corresponding to 40 games from the Spanish professional leagues. The effects of the predictor variables on successful ball possessions according to game period were analysed using binary logistic regressions. Results from men's teams show interactions with number of passes and ending player during the first five minutes, with starting and ending zone, defensive systems, screens used and possession duration during the middle thirty minutes, and there were interactions with passes used, possession duration and players involved during the last five minutes. Results from women's teams show interactions with starting and ending zone, passes used, defensive systems and ending player during the first five minutes, and with starting and ending zone, and screens used during the middle thirty minutes. The results show no interaction with situational variables in men's basketball, while league stage was important during the middle thirty minutes and last five minutes in women's basketball, whereas match status was only important during the last five minutes.     

Above a swamp: A theory of high-quality scientific production

We elaborate a model of the incentives of scientists to perform activities of control and criticism when these activities, just like the production of novel findings, are costly, and we study the strategic interaction between these incentives. We then use the model to assess policies meant to enhance the reliability of scientific knowledge. We show that a certain fraction of low-quality science characterizes all the equilibria in the basic model. In fact, the absence of detected low-quality research can be interpreted as the lack of verification activities and thus as a potential limitation to the reliability of a field. Incentivizing incremental research and verification activities improves the expected quality of research; this effect, however, is contrasted by the incentives to free ride on performing verification if many scientists are involved, and may discourage scientists to undertake new research in the first place. Finally, softening incentives to publish does not enhance quality, although it increases the fraction of detected low-quality papers. We also advance empirical predictions and discuss the insights for firms and investors as they “scout” the scientific landscape.     

A bottlenose dolphin discriminates visual stimuli differing in numerosity

A bottlenose dolphin was trained to discriminate two simultaneously presented stimuli differing in numerosity (defined by the number of constituent elements). After responding correctly to stimuli consisting of three-dimensional objects, the dolphin transferred to two-dimensional stimuli. Initially, a variety of stimulus parameters covaried with the numerosity feature. By systematically controlling for these stimulus parameters, it was demonstrated that some of these attributes, such as element configuration and overall brightness, affected the animal’s discrimination performance. However, after all the confounding parameters were under control, the dolphin was able to discriminate the stimuli exclusively on the basis of the numerosity feature. The animal then achieved a successful transfer to novel numerosities, both intervening numerosities and numerosities outside the former range. These findings provide substantial evidence that the dolphin could base his behavior on the numerosity of a set independently of its other attributes and that he represented ordinal relations among numerosities.     

Integrated and Predictive Systems for Preventive Conservation

ABSTRACT

Forecasting the dynamics of alteration in materials, in particular the timescale of degradation, is relevant to preventive conservation, and great deal of effort has gone into developing new models for the kinetics of physical and chemical phenomena affecting materials. Creating monitoring systems able to assess the evolution of degradation processes that inform intervention programs is necessary to ensure the protection of historical and artistic heritage. The Research Unit for Integrated and Predictive Systems (SIP) is presented: it develops new tools and algorithms to study the alteration of materials using non-invasive techniques and passive monitoring, as well as new mathematical models to predict how the surfaces of materials degrade with time. The paper focuses on the Arch of Augustus and presents initial results from two virtual sensors used to ‘monitor’ environmental conditions outdoors. These systems do not need a permanent, invasive network of sensors in situ. They rely instead on local infrastructure for measuring air quality, and adopt smart information fusion algorithms to predict the environment around the cultural heritage site. Virtual sensors can provide an effective control system that highlights specific conditions linked to specific forms of alteration.