Control of sideslip and yaw rate in 4-wheel steering car using partial decoupling and individual channel design

This paper presents a new steering control structure for cars equipped with 4-wheel steering. This control structure is based on a simplified linear model of the lateral dynamics of such cars and aims to decouple the control of sideslip from the control of yaw rate. The control design is based on a linear multivariable plant which incorporates the model of the lateral dynamics mentioned above and whose inputs are linear combinations of the front and rear steering angles. The plant also contains a cross-feedback element. The matrix transfer function of the resulting plant is upper-triangular (partially decoupled). The MIMO design problem can then be recast as two SISO design problems using channel decomposition according to the Individual Channel Design (ICD) paradigm. The proposed control structure has been applied to design sideslip and yaw rate controllers using a more accurate model of the lateral dynamics of 4-wheel steering cars. This model incorporates the tyre force dynamics and the steering actuators. Simulations are used to illustrate the performance and robustness of the designed controllers

Breu “memòria” d’un esforç mai prou aconseguit: la recerca de la dignitat i la justícia. Sobre els drets... i els deures

La Declaració universal dels drets humans (DUDH) és el referent teòric del nostre temps que aspira al seu acompliment. Malgrat això, tal aspiració resta molt lluny de veure’s satisfeta. N’hi ha prou a donar un cop d’ull a ’actualitat mundial per adonar-se que la distància entre la Declaració i la realitat és, gairebé, insuperable per diversos motius, no per la impossibilitat en si mateixa que així sigui. L’article fa un esbós de l’itinerari històric de tal aspiració amb diversitat de formulacions al llarg del temps: des del tercer mil·lenni aC fins avui hom ha manifestat, i ha volgut frenar, la desigualtat social, l’abús, la manipulació... la negació sistemàtica dels drets fonamentals, un viure indigne de qui ho pateix. Qui provoca tal patiment, o el consent, malgrat les aparences, se situa en un nivell infrahumà, es degrada a si mateix i, també, el seu entorn. PARAULES CLAU: drets, deures, procés històric, educació. ABSTRACT: The Universal Declaration of Human Rights (UDHR) is the theoretical reference of our times which aims at being accomplished. Despite this, this aim is far from being achieved. Suffice it to take a look at the world’s current affairs to realize that the gap between the Declaration and reality is almost insurmountable for different reasons, but not because of its impossibility. This article briefly describes the historical itinerary of this aim with different formulations throughout time: from the third millennium BC until today, people have wanted to stop social inequalities, abuse, manipulation… the systematic denial of fundamental rights, an undignified life for those who suffer. Those who produce this suffering, or let it happen, despite appearances, place themselves at an infrahuman level, degrading themselves and their environment. KEYWORDS: rights, duties, historical process, educatio

La salut com a problema. "Sobre l'oblit"

Des del s. XVIII fins a mitjan s. XX s’ha posat més l’accent en la malaltia com a realitat biològica que en la salut com a vivència complaent, harmònica i participativa. Oblidant, sovint, que en la salut intervenen factors socials, psicològics, mediambientals, polítics... i biològics. També s’ha posat més l’accent en la guarició, alleujament, de la malaltia que no pas en la prevenció, promoció i manteniment del benestar, o bé de la salut, si així se’n vol dir. Tampoc se sap ben bé on queden les qualitats essencialment humanes en la consideració de la salut. L’article “recorda”, una vegada més, que la salut s’encarna en el benestar i, aquest, és quan la vida es viu amb un “sentiment” de complaença compartit i participatiu. PARAULES CLAU: persona, factors socials, salut/benestar. ABSTRACT: From the 18th century until mid-20th century, emphasis was laid upon disease as a biological reality rather than upon health as a pleasant, harmonious and participatory experience; overlooking, sometimes, that in health the relevant factors can be social, psychological, environmental, political... and biological. There was also more focus on curing and alleviating the disease rather than on preventing, promoting and keeping well-being, or health, if you like. The role of those essentially human qualities when onsidering health is also uncertain. This article “reminds” us, once again, that health lies in well-being, which is when life is lived with a shared and participatory “feeling” of pleasantness. KEY-WORDS: person, social factors, health/well-being

Is 32,17: "El fruit de la justícia serà la pau". (I). Sobre "shalom".

RESUM: Aquesta primera part vol ser una introducció al tema central: shalom. S’aborden qüestions bàsiques sobre la justícia al ser aquesta lacausa de la tan anomenada pau. Recórrer als textos, a l’esperit, de l’Antic Testament és posar en evidènciala seva actualitat. La Creació ha emmalaltit; ahir, avui i abans-d’ahir. Hi ha una simptomatologia reconeguda en una sola paraula: injustícia, amb un abast significatiu que arriba i s’escampa per arreu essent, sovint, la conseqüència lògica d’una manera de fer pròpia d’un temps i un lloc que es legitima a si mateixa. Els textos bíblics són un clam a fi que hom no s’abandoni ni s’engresqui en estils de vida que no es corresponen amb el cultiu de la bondat original amb què tot va ser creat. D’aquí una breu reflexió sobre l’actualitat del tema que ens porta, tot seguit, cap a alguns textos que no exhaureixen ni de bon tros tots els que es podrien citar.PARAULES CLAU: justícia, pobresa, espiritualitat.Is 32,17: «The fruit of that righteousness will be peace». (I). On ShalomABSTRACT: This first part is aimed as an introduction to the central topic: Shalom. Basic questions around justice are presented, as this is the cause of the so much mentioned peace. Resorting to the texts, to the spirit, of the Old Testament is to show their current value. Creation has become ill: yesterday, today, and the day before yesterday. There are symptoms recognised with one single word: injustice, with a remarkable scope, reaching everywhere, often being the logical consequence of a self-legitimated way of doing things that is particular to a time and place. The biblical texts are a call so that people neither give in to nor enthuse over lifestyles that do not comply with nurturing the original goodness that everything was created with. Then, a brief reflection on the current validity of this topic, which leads us to some texts that are by no means all of those that we could cite.KEYWORDS: justice, poverty, spirituality

A sequential model for older workers’ labor transitions after a health shock

In this work we study older workers’ (50—64) labor force transitions after a health/disability shock. We find that the probability of keeping working decreases with both age and severity of the shock. Moreover, we find strong interactions between age and severity in the 50—64 age range and none in the 30–49 age range. Regarding demographics we find that being female and married reduce the probability of keeping work. On the contrary, being main breadwinner, education and skill levels increase it. Interestingly, the effect of some demographics changes its sign when we look at transitions from inactivity to work. This is the case of being married or having a working spouse. Undoubtedly, leisure complementarities should play a role in the latter case. Since the data we use contains a very detailed information on disabilities, we are able to evaluate the marginal effect of each type of disability either in the probability of keeping working or in returning back to work. Some of these results may have strong policy implications.Health shocks, disability, labor force transitions, older workers, Spain

Història, Sociologia, Teologia. Una mirada complementària. Sobre l'Antic Testament

RESUM: La sociologia és l’explicació i interpretació de la vida social de l’ésser humà, de la seva dimensió cultural i del dinamisme que l’acompanya al llarg de la història. És reflexió crítica. És fonamentació de la realitat social, recerca de la seva causalitat i projecció de futur, qüestionament constant. És compromís actuant a favor del benestar. Les formes socials de l’antic Israel, canvis, influències, representacions... se’ns fan avinents en el marc geogràfic i històric dels textos de la mà de diversitat de disciplines que ajuden a fer-nos una idea, mai definitiva, de com els esdeveniments que s’hi relaten es viuen, o bé s’il·lustren, per part de persones en una determinada situació social i política on es gesten mentalitats, ideologies, creences i interessos. Ni l’exegesi ni l’hermenèutica poden prescindir de la mirada sociològica que ens apropa a les formes i estils de vida dels seus protagonistes, que ho són en diversitat de “formats”.PARAULES CLAU: Antic Testament, Sociologia, TeologiaHistory, Sociology, Theology. A Complementary Vision. On the Old TestamentABSTRACT: Sociology is the explanation and interpretation of the human being’s social life, cultural dimension and dynamism throughout history. It is a critical reflection. It is the basis for social reality, search for its causality and future projection, constant questioning. It is commitment towards well-being. Social forms in Ancient Israel, changes, influences, representations… are made apparent in the geographical and historical framework of these texts thanks to the diversity of disciplines that help us some how understand how those events explained in them are lived or illustrated by people in certain social and political situations where mentalities, ideologies, beliefs and interests are shaped. Neither exegesis nor hermeneutics can disregard the sociological perspective that approaches us to the forms and life styles of their protagonists in their different “formats”.KEYWORDS: Old Testament, Sociology, Theology

La transformació pacífica i efectiva de les persones i llurs societats amb l’objectiu de millora personal i en la convivència. Sobre el “servei”

El servei està desacreditat. Hi ha certa prevenció a utilitzar el terme. Sovint s’entén com una acció de dependència humiliant, indigna de la persona lliure. Però l’article apunta a una altra mirada sobre el servei. Una mirada, i una realitat, tan genuïna com l’altra. No és cap novetat el crèdit i els beneficis que té l’actitud de servei vers els altres i com, aquesta actitud, sorgeix tant de la lliure decisió personal com de les mancances i necessitats particulars i col·lectives com de l’actitud que hom espera, demana i hauria de caracteritzar el servei públic. Si més no. L’article és un apunt. Enceta una reflexió amb la qual vol recordar que el terme té un altre sentit tan genuí com el que vulgarment se li atribueix. I, entre línies, es planteja la pregunta: què determina el servei? PARAULES CLAU: servei, servir, procés, antropologia, espiritualitat. The Peaceful and Effective Transformation of People and Their Societies with the Objective of Personal Improvement and Life Together. On "Service” ABSTRACT: Service is discredited. The use of the term is even avoided. It is often understood as an action of humiliating dependence, improper of a free person. But this article points at another vision about service. A vision, and a reality, as genuine as the other. The credit and benefits of the attitude of service towards others are not a novelty, as well as how this attitude springs both from the free personal decision, the individual and group shortages and needs and from the attitude that we expect from, require and should characterize public service. At least it should. This article is a few notes. It begins a reflection that is aimed at reminding us that the term has another meaning, as genuine as the one that it has commonly been given. And, between the lines, we pose the question: what determines service? KEYWORDS: Service, serving, process, anthropology, spirituality

Award errors and permanent disability benefits in Spain

There is a controversial debate about the effects of permanent disability benefits on labor market behavior. In this paper we estimate equations for deserving and receiving disability benefits to evaluate the award error as the difference in the probability of receiving and deserving using survey data from Spain. Our results indicate that individuals aged between 55 and 59, self-employers or working in an agricultural sector have a probability of receiving a benefit without deserving it significantly higher than the rest of individuals. We also find evidence of gender discrimination since male have a significantly higher probability of receiving a benefit without deserving it. This seems to confirm that disability benefits are being used as an instrument for exiting the labor market for some individuals approaching the early retirement or those who do not have right to retire early. Taking into account that awarding process depends on Social Security Provincial Department, this means that some departments are applying loosely the disability requirements for granting disability benefits.Disability benefits, Award error, Early retirement, Social security

Study of Johnsons Glacier (Livingston Island, Antarctica) by means of shallow ice cores and their tephra and by analysis of 137Cs content

With the aim of monitoring the dynamics of the Livingston Island ice cap, the Departament de Geodinàmica i Geofísica of the Universitat de Barcelona began yearly surveys in the austral summer of 1994-95 on Johnsons Glacier. During this field campaign 10 shallow ice cores were sampled with a manual ve rtical ice-core drilling machine. The objectives were: i) to detect the tephra layer accumulated on the glacier surface, attributed to the 1970 Deception Island pyroclastic eruption, today interstratified; ii) to verify wheter this layer might serve as a reference level; iii) to measure the 137Cs radio-isotope concentration accumulated in the 1965 snow stratum; iv) to use the isochrone layer as a mean of verifying the age of the 1970 tephra layer; and, v) to calculate both the equilibrium line of the glacier and average mass balance over the last 28 years (1965-1993). The stratigraphy of the cores, their cumulative density curves and the isothermal ice temperatures recorded confirm that Johnsons Glacier is a temperate glacier. Wind, solar radiation heating and liquid water are the main agents controlling the ve rtical and horizontal redistribution of the volcanic and cryoclastic particles that are sedimented and remain interstratified within the glacier. It is because of this redistribution that the 1970 tephra layer does not always serve as a very good reference level. The position of the equilibrium line altitude (ELA) in 1993, obtained by the 137Cs spectrometric analysis, varies from about 200 m a.s.l. to 250 m a.s.l. This indicates a rising trend in the equilibrium line altitude from the beginning of the 1970s to the present day. The varying slope orientation of Johnsons Glacier relative to the prevailing NE wind gives rise to large local differences in snow accumulation, which locally modifies the equilibrium line altitude. In the cores studied, 137Cs appears to be associated with the 1970 tephra layer. This indicates an intense ablation episode throughout the sampled area (at least up to 330 m a.s.l), which probably occurred synchronically to the 1970 tephra deposition or later. A rough estimate of the specific mass balance reveals a considerable accumulation gradient related to the increase with altitude

L'antropologia de la salut. Cultura, preocupació social i salut (I)

En aquesta primera part, l'article recorda breument la variant significació del concepte cultura, per abordar el tema de la seva fenomenologia des de les categories de les representacions, els significats i les expectatives, i dibuixar la trajectòria d'un marc teòric des del qual estructurar un tipus de discurs sobre la salut. És en l'apartat de les expectatives on el text s'estén i focalitza l'atenció en la religió, com a expressió social dels valors, i en la lectura que la Constitució Gaudium et spes fa de la cultura, com una aproximació a la realitat social actual. En un darrer pas, s'estableixen lligams de simpatia entre l'anomenada antropologia de l'acció i la construcció de la salut