481 research outputs found

    El Iris del pueblo, òrgan del republicanisme federal a Mallorca (1869-1873)

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    With this paper we analyze the federal republicanism in Majorca through their official organ, El Iris del Pueblo, which was published daily in Palma between 1869 and 1873. We start with the idea that Republicans actively contribute to the modernization process of Mallorca with his performances in various fields: politics, economy, education and culture. The great debates that emerge from reading the paper that we work here will give us an idea of the ideological characterization of the republicans of Majorca.Amb aquest treball pretenem analitzar el republicanisme federal a Mallorca a través del seu òrgan oficial, El Iris del Pueblo, diari que es va publicar a Palma entre 1869 i 1873. Partim de la idea que els republicans contribuïren activament al procés de modernització de Mallorca amb les seves actuacions en diferents àmbits: la política, l’economia, l’educació i la cultura. Els grans debats que es desprenen de la lectura de la publicació que aquí treballam ens podran donar una idea de la caracterització ideològica del republicanisme mallorquíCon este trabajo pretendemos analizar el republicanismo federal en Mallorca a través de su órgano oficial, El Iris del Pueblo, diario que se publicó en Palma entre 1869 y 1873. Partimos de la idea de que los republicanos contribuyeron activamente al proceso de modernización de Mallorca con sus actuaciones en diferentes ámbitos: la política, la economía, la educación y la cultura. Los grandes debates que se desprenden de la lectura de la publicación que aquí trabajamos nos podrán dar una idea de la caracterización ideológica del republicanismo mallorquín

    A Single-Loop DC Motor Control System Design with a Desired Aperiodic Degree of Stability

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    The application of the original analytical approach for Pi-controller synthesis of a stable second-order plant is considered. This approach allows finding controller parameters without any intensive computing by using the direct expressions. The plant model is obtained on the basis of identification, which is based on the automated real-interpolation method. The results of natural experiments are given

    Series-Parallel and Parallel Identification Schemes for a Class of Continuous Nonlinear Systems

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    Fig. 4(a) shows the parameter estimates under the existence of the measmable disturbance (di = 5, a\ = 0) with the parameter estimates under the ideal condition (di = a\ = 0) overlaid. Since the inserted DDR's remove the disturbance from the inputoutput relation, the disturbance does not slow down the identification speed. Fig. 4(6) shows the parameter estimates under the existence of the unmeasurable disturbance (di = 0, d 2 = 1) with the parameter estimates under the ideal condition (di = di = 0) overlaid. There exists no difference between the two cases as far as the identification speed is concerned. In the simulation, the step disturbances, di and d 2 , were injected to the plant at k = 0. Thus, strictly speaking, at k = 0, di(k) and d 2 (fc) did not satisfy equation V Conclusions Adverse effects of deterministic disturbances in linear identification have been pointed out, and a method to remove such effects has been presented. This method works for measurable and unmeasurable disturbances which can be regarded as the outputs of free systems with known dynamics. The unmeasurable disturbance must always be removed to achieve successful identification. When the disturbance is measurable, however, it does not have to be removed if it can provide a positive contribution to identification. A constant disturbance was shown to slow down the identification speed. The best results will be obtained if one selects a DDR which removes only undesirable disturbances. In this technical brief, discrete series-parallel and parallel identification schemes for single-input, single-output systems were considered. The same principle, however, can be extended to other situations including the continuous time case and multi-input, and multi-output case. References 1 Astrom, K. J., and Eykhoff, P., "System Identification -A Survey," Automatica, Vol. 7, 1971, pp. 123-16

    Ball on a beam: stabilization under saturated input control with large basin of attraction

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    This article is devoted to the stabilization of two underactuated planar systems, the well-known straight beam-and-ball system and an original circular beam-and-ball system. The feedback control for each system is designed, using the Jordan form of its model, linearized near the unstable equilibrium. The limits on the voltage, fed to the motor, are taken into account explicitly. The straight beam-and-ball system has one unstable mode in the motion near the equilibrium point. The proposed control law ensures that the basin of attraction coincides with the controllability domain. The circular beam-and-ball system has two unstable modes near the equilibrium point. Therefore, this device, never considered in the past, is much more difficult to control than the straight beam-and-ball system. The main contribution is to propose a simple new control law, which ensures by adjusting its gain parameters that the basin of attraction arbitrarily can approach the controllability domain for the linear case. For both nonlinear systems, simulation results are presented to illustrate the efficiency of the designed nonlinear control laws and to determine the basin of attraction

    Identification of single-input–single-output quantum linear systems

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    The purpose of this paper is to investigate system identification for single-input–single-output general (active or passive) quantum linear systems. For a given input we address the following questions: (1) Which parameters can be identified by measuring the output? (2) How can we construct a system realization from sufficient input-output data? We show that for time-dependent inputs, the systems which cannot be distinguished are related by symplectic transformations acting on the space of system modes. This complements a previous result of Guţă and Yamamoto [IEEE Trans. Autom. Control 61, 921 (2016)] for passive linear systems. In the regime of stationary quantum noise input, the output is completely determined by the power spectrum. We define the notion of global minimality for a given power spectrum, and characterize globally minimal systems as those with a fully mixed stationary state. We show that in the case of systems with a cascade realization, the power spectrum completely fixes the transfer function, so the system can be identified up to a symplectic transformation. We give a method for constructing a globally minimal subsystem direct from the power spectrum. Restricting to passive systems the analysis simplifies so that identifiability may be completely understood from the eigenvalues of a particular system matrix

    Applicability of an abbreviated version of the Child-OIDP inventory among primary schoolchildren in Tanzania

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    Background: There is a need for studies evaluating oral health related quality of life (OHRQoL) of children in developing countries. Aim: to assess the psychometric properties, prevalence and perceived causes of the child version of oral impact on daily performance inventory (Child- OIDP) among school children in two socio-demographically different districts of Tanzania. Socio-behavioral and clinical correlates of children's OHRQoL were also investigated.Method: One thousand six hundred and one children ( mean age 13 yr, 60.5% girls) attending 16 ( urban and rural) primary schools in Kinondoni and Temeke districts completed a survey instrument in face to face interviews and participated in a full mouth clinical examination. The survey instrument was designed to measure a Kiswahili translated and culturally adapted Child-OIDP frequency score, global oral health indicators and socio-demographic factors. Results: The Kiswahili version of the Child- OIDP inventory preserved the overall concept of the original English version and revealed good reliability in terms of Cronbach's alpha coefficient of 0.77 ( Kinondoni: 0.62, Temeke: 0.76). Weighted Kappa scores from a test-retest were 1.0 and 0.8 in Kinondoni and Temeke, respectively. Validity was supported in that the OIDP scores varied systematically and in the expected direction with self-reported oral health measures and socio-behavioral indicators. Confirmatory factor analyses, CFA, confirmed three dimensions identified initially by Principle Component Analysis within the OIDP item pool. A total of 28.6% of the participants had at least one oral impact. The area specific rates for Kinondoni and Temeke were 18.5% and 45.5%. The most frequently reported impacts were problems eating and cleaning teeth, and the most frequently reported cause of impacts were toothache, ulcer in mouth and position of teeth. Conclusion: This study showed that the Kiswahili version of the Child- OIDP was applicable for use among schoolchildren in Tanzania

    Frequency Locking of an Optical Cavity using LQG Integral Control

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    This paper considers the application of integral Linear Quadratic Gaussian (LQG) optimal control theory to a problem of cavity locking in quantum optics. The cavity locking problem involves controlling the error between the laser frequency and the resonant frequency of the cavity. A model for the cavity system, which comprises a piezo-electric actuator and an optical cavity is experimentally determined using a subspace identification method. An LQG controller which includes integral action is synthesized to stabilize the frequency of the cavity to the laser frequency and to reject low frequency noise. The controller is successfully implemented in the laboratory using a dSpace DSP board.Comment: 18 pages, 9 figure

    Prevalence and Socio-behavioral Influence of Early Childhood Caries, ECC, and Feeding Habits among 6-36 Months Old Children in Uganda and Tanzania.

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    Early childhood caries (ECC) is a serious problem that has remained unexplored in sub-Saharan Africa. This study aimed to identify possible socio-behavioral correlates of ECC focusing 6-36 months old children and their caretakers.\ud Cross sectional studies were conducted in a high fluoride rural area, Manyara, Tanzania and a low fluoride urban area, Kampala, Uganda. Totals of 1221 and 816 child - caretaker pairs attending health care facilities for growth monitoring were recruited in Manyara and Kampala, respectively. All caretakers completed face to face interviews at the health care facility. Children underwent oral clinical examination whereby ECC and Enamel hypoplasia were recorded using the dmft (WHO 1997) and the DDE index (FDI 1992). The prevalence of ECC was 3.7% in Manyara and 17.6% in Kampala. According to multiple logistic regression analyses, received oral health information from health worker was the strongest determinant of ECC in Manyara, adjusted OR 0.3, 95% CI 0.09 - 0.93. In Kampala, visible plaque, high sugar intake and presence of enamel hypoplasia associated with ECC, adjusted ORs 2.8 (95% CI 1.61- 4.95), 3.0 (95% CI 1.39 - 6.34) and 2.3 (95% CI 1.36 - 3.95). Oral health education aimed at caretakers of 6-36 months, including health care workers' information regarding the detrimental consequences for oral health of frequent sugar consumption and poor oral hygiene is important for prevention of ECC in Tanzania and Uganda

    Gene expression and matrix turnover in overused and damaged tendons

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    Chronic, painful conditions affecting tendons, frequently known as tendinopathy, are very common types of sporting injury. The tendon extracellular matrix is substantially altered in tendinopathy, and these changes are thought to precede and underlie the clinical condition. The tendon cell response to repeated minor injuries or “overuse” is thought to be a major factor in the development of tendinopathy. Changes in matrix turnover may also be effected by the cellular response to physical load, altering the balance of matrix turnover and changing the structure and composition of the tendon. Matrix turnover is relatively high in tendons exposed to high mechanical demands, such as the supraspinatus and Achilles, and this is thought to represent either a repair or tissue maintenance function. Metalloproteinases are a large family of enzymes capable of degrading all of the tendon matrix components, and these are thought to play a major role in the degradation of matrix during development, adaptation and repair. It is proposed that some metalloproteinase enzymes are required for the health of the tendon, and others may be damaging, leading to degeneration of the tissue. Further research is required to investigate how these enzyme activities are regulated in tendon and altered in tendinopathy. A profile of all the metalloproteinases expressed and active in healthy and degenerate tendon is required and may lead to the development of new drug therapies for these common and debilitating sports injuries
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