Observer design for position and velocity bias estimation from a single direction output

This paper addresses the problem of estimating the position of an object moving in $R^n$ from direction and velocity measurements. After addressing observability issues associated with this problem, a nonlinear observer is designed so as to encompass the case where the measured velocity is corrupted by a constant bias. Global exponential convergence of the estimation error is proved under a condition of persistent excitation upon the direction measurements. Simulation results illustrate the performance of the observer.Comment: 6 pages, 6 figure

Tropical Cyclone Movement Forecasts Based on Observations from Satellites

The article of record as published may be found at http://dx.doi.org/10.1175/1520-0450(1975)0142.0.CO;2A method to predict 24 h movement of tropical cyclones using consecutive daily satellite views is described. The method is based on the observation that changes in the location of major structural features of the storm are correlated with changes in the direction of movement of the storm centers. Major structural features appear to retain the same relative location with respect to the direction of movement of the storm center. The rotation of features noted in comparing satellite views over a 24 h period is frequently found to approximate in sense and value the further deflection the storm will.take in its track during the following 24 h. A test evaluation of the method was conducted by seven individuals using 31 separate data sets of satellite data. For the purposes of the test only direction of movement forecasts were made and storm center displacement was neglected. The results on a post-analysis, nonreal- time, basis compared favorably with official 24 h forecasts

Sex in Penicillium series Roqueforti

Various fungi were isolated during the course of a survey in a cold-store of apples in the Netherlands. One of these fungi belongs to the genus Penicillium and produces cleistothecia at 9 and 15 °C. A detailed study using a combination of phenotypic characters, sequences and extrolite patterns showed that these isolates belong to a new species within the series Roqueforti. The formation of cleistothecia at low temperatures and the inability to produce roquefortine C, together with a unique phylogenetic placement, make these isolates a novel entity in the Roqueforti series. The name Penicillium psychrosexualis sp. nov. (CBS 128137T) is proposed here for these isolates

Polyphasic taxonomy of Aspergillus section Sparsi

Aspergillus section Sparsi includes species which have large globose conidial heads with colours ranging from light grey to olive-buff. In this study, we examined isolates of species tentatively assigned to section Sparsi using a polyphasic approach. The characters examined include sequence analysis of partial β-tubulin, calmodulin and ITS sequences of the isolates, morphological and physiological tests, and examination of the extrolite profiles. Our data indicate that the revised section Sparsi includes 10 species: A. anthodesmis, A. biplanus, A. conjunctus, A. diversus, A. funiculosus, A. implicatus, A. panamensis, A. quitensis, A. sparsus, and the new taxon A. haitiensis. The recently described A. quitensis and A. ecuadorensis are synonyms of A. amazonicus based on both molecular and physiological data. The white-spored species A. implicatus has also been found to belong to this section. Aspergillus haitiensis sp. nov. is characterised by whitish colonies becoming reddish brown due to the production of conidial heads, and dark coloured smooth stipes. The taxon produces gregatins, siderin and several unknown but characteristic metabolites

A stochastic framework for modeling the population dynamics of convective clouds

A stochastic prognostic framework for modeling the population dynamics of convective clouds and representing them in climate models is proposed. The framework follows the non-equilibrium statistical mechanical approach to constructing a master equation for representing the evolution of the number of convective cells of a specific size and their associated cloud-base mass flux, given a large-scale forcing. In this framework, referred to as STOchastic framework for Modeling Population dynamics of convective clouds (STOMP), the evolution of convective cell size is predicted from three key characteristics of convective cells: (i) the probability of growth, (ii) the probability of decay, and (iii) the cloud-base mass flux. STOMP models are constructed and evaluated against CPOL radar observations at Darwin and convection permitting model (CPM) simulations. Multiple models are constructed under various assumptions regarding these three key parameters and the realisms of these models are evaluated. It is shown that in a model where convective plumes prefer to aggregate spatially and the cloud-base mass flux is a non-linear function of convective cell area, then the mass flux manifests a recharge-discharge behavior under steady forcing. Such a model also produces observed behavior of convective cell populations and CPM simulated cloud-base mass flux variability under diurnally varying forcing. In addition to its use in developing understanding of convection processes and the controls on convective cell size distributions, this modeling framework is also designed to be capable of serving as a non-equilibrium closure formulations for spectral mass flux parameterizations

The cost of discipleship and the reward of righteousness

CHAPTER ONE. In the Old Testament we meet with the problem of suffering and reward, and the attempts made to resolve it. It becomes the one great problem after the time of the Exile. Most commentators are agreed that it grew to hold that place in relation to the increase of importance of the individual in Hebrew thinking. While certain aspects of the problem are presented in Jeremiah, Ezekiel, Isaiah, and Psalm 73, the most important contributions are made by the Deuteronomist and the poet who wrote the Book of Job. The Deuteronomist theory presents the belief that there is a rigid correspondence between the sins of the individual and his suffering. The reply in Job makes it clear that this is not so. Job himself passes through the desperate situation of feeling deserted by God to a certain faith that whatever happens to him, God is faithful. CHAPTER TWO. Jesus' teaching on "discipleship". Basically Jesus's teaching centres around Mark 8 : 34, "Whosoever will come after me, let him deny himself and take up his cross, and follow me". The cost of discipleship from this point of view means, then, that even as Jesus Himself bears the cross for the salvation of the world, so the disciple is called upon to bear that cross in association with his Lord. Jesus offers the reward of both a present foretaste and a future consummation of eternal life, as the disciple shares in His resurrection. St. Paul's teaching of "Life in Christ". The central teaching of Paul is found in Romans 6 : 11, "Likewise reckon ye also yourselves to be dead indeed unto sin, but alive unto God through Jesus Christ our Lord." The cost of discipleship is death, the death of self- will. It means being crucified with Christ. The reward of the righteous man is both a present and future participation in the risen life of Christ. CHAPTER THREE The need of man. Because man is a sinner, being estranged from God in whose image he was created, he stands in need of being reconciled to God. This he cannot do himself because, to his sin, he is not able to make the full sacrifice of his self-will. "Man requires to be put right with God because as a matter of fact he is not right." The Christ. Only in the person of the God-man is God able to effect man's resolution. Jesus, the Christ, who alone of all men did not participate in the sinfulness of man, is this God-man, realising in Himself the fact that salvation can only be wrought by one who is both God and man. The necessity of the Cross. The death of the Christ is seen to be necessary both from the side of man and from that of God. It was essential that the Christ should give His life for man; everything for His purpose of salvation turns on the will to die. He must give himself to reconcile man to God. The sacrifice of the Cross. Seen in the context of the Old Testament sacrificial system, what is important about the sacrifice of the Christ is that on the cross He offered up His life for man. The sacrifice of the Christ is both in the category of divine revelation and that of human response. It is the love of God in its utter self-offering making a way whereby the sinner might be reconciled to Him. The use of the Ransom Theory of the atonement is regarded as inadequate for expressing this cost. Basically it is a costly sacrifice because it is the self-offering of the Son of God upon the cross. CHAPTER FOUR The New Testament picture. A closer analysis is made of the New Testament teaching of discipleship, where it is seen that it is required of men that he should make, like the Christ, the costly sacrifice of himself. Soren Kierkegaard. This existential thinker felt the need of awakening men to a full recognition of the costliness of life. Despair. Man, due to his state of sinfulness is in despair, for "sin can be defined as despair at not willing to be oneself or not willing to be oneself before God." It is necessary to make the leap of faith to pass from this despair. The Three Stages. These are the aesthetical, ethical and religious stages. The individual must enter the last by making the leap of faith out of his despair; and this leap means the costly commitment of the self to the Christ. "Purify your hearts." In this book, Kierkegaard analyses man's double-mindedness. He comes to two conclusions. "If anybody would will the Good truly, then he must with knowledge of himself be ready to renounce all double-mindedness. If anybody would will the Good truly, then he must be ready to do all for the Good, and suffer for for the Good." His teaching on the cost of discipleship could be summed up thus : "The negating of one's finite self, or the negating of one's finitude means for him nothing less than the conscious sacrifice of all that is finite." Paul Tillich. Tillich deals with the ultimate problem of being and non-being, and in the "Courage to be" he develops the reactions of the individual when he is faced with the possibility of his non-being. The individual can either lose himself in his world by the courage to be as a part, or lose his world in himself by the courage to be as himself. These two forms of courage are transcended by the courage to accept acceptance, which is the ultimate courage to be, in which the individual accepts the fact that though he is sinful, yet God accepts him. This courage is the outcome of faith, which is found in an encounter with the New Being, in which the self is lost in the Christ, being found also in the Christ. The disciple surrenders himself that he may be made more truly himself. CHAPTER FIVE In this chapter an attempt is made to analyse the reward of righteousness. This reward is firstly seen to be the outcome of the life of discipleship and not its motive. Basically it is found in the new quality of life which is called eternal life. It is a reward both in the future and in the present. In the future it is the fullness of life in communion, peace and joy in the presence of God. In the present it is a foretaste of that life which is to come, a present possession in the midst of finitude of communion, peace and joy with God. Ultimately this means participation in the resurrection of the Christ. CHAPTER SIX We can conclude from this thesis, then, that Jesus the Christ is the prototype of the Christian. Discipleship is costly because it means participation in His utter self-offering of Himself; and the righteous man, who is the one who by faith commits himself to and in the Christ, is rewarded with the new quality of eternal life. The death and resurrection of Jesus the Christ are the criteria of the cost of discipleship and the reward of the righteous man

Creating A ‘Tax Paying Informal Traders’ Culture in Zimbabwe: Can This Be Achievable?

This paper attempted to give reasons why it is difficult for Zimbabwe and other developing countries tax the informal sector. This study adopted both a desk and library research approaches. This paper has established that there are many well researched practical recommendations in the literature on how to tax the informal sector and governments have failed to implement these practical strategies. However this paper recommended that a three factor audit trail framework must be developed in order to improve informal sector tax revenue. Keywords: Taxation, Informal Traders, Culture, Zimbabwe, Myth, Realit