935 resultados para PI controller


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Portabilidad del sistema de control domótico OpenDomo a la arquitectura ARM (Raspberry Pi).

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Foram avaliadas as alterações nas características estruturais de ácidos húmicos (AH) decorrentes da adição de matéria orgânica de resíduos urbanos. Os AH foram extraídos da camada superficial (0-20 cm) de um Argissolo Vermelho-Amarelo (Seropédica, RJ) e de um Latossolo Vermelho Amarelo (Piraí, RJ), ambos tratados com o equivalente a 80 t ha-1 (em base seca) de composto de lixo urbano e lodo de estação de tratamento de esgotos. O tempo de incubação em laboratório foi de 24 semanas à temperatura ambiente e umidade mantida na capacidade de campo. Para caracterizar os AH, foram utilizadas a análise elementar, a ressonância magnética nuclear (RMN) de 13C e Pirólise acoplada à cromatografia gasosa e a espectrometria de massas (Pi-CG/EM). A análise de RMN 13C permitiu observar alterações na composição molecular dos AH de forma clara, principalmente, pelo aumento do teor de C mono e di oxigenados (δC 50-110) e pela diminuição dos teores de grupos CH2 e CH3 (δC 50-110). O aumento no teor de carboidratos evidencia a presença de estruturas mais lábeis nos AH com adição dos resíduos. Em adição, a técnica de Pi-CG/EM permitiu verificar diferenças qualitativas significativas nos compostos orgânicos, provenientes da fragmentação térmica dos AH com incorporação de novas estruturas, sobretudo da fração lipídica e de derivados de carboidratos (furanos), nas amostras de solos tratados com ambos os resíduos orgânicos. O uso em conjunto das técnicas analíticas de RMN 13C e de Pi-CG/EM foi eficiente para avaliar as mudanças na composição molecular de ácidos húmicos decorrentes da adição de resíduos orgânicos de origem urbana.

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Estudiem les característiques edàfiques del sòl dels boscos joves de pi negre (Pinus uncinata) de l’estatge subalpí del Parc Nacional d’Aigüestortes i Estany de Sant Maurici corresponents a àrees de reforestació entre els anys 1956 i 2008. Aquest estudi s’ha fet de 29 parcel•les d’aquesta zona situades sobre diferents tipus de substrat, orientació i pendent. S’ha caracteritzat el sòl a partir de l’anàlisi de textura, matèria orgànica, nitrogen total, fòsfor, sodi, potassi, magnesi, calci, capacitat d’intercanvi catiònic, acidesa del sòl, relació C/N. Els resultats confirmen que es tracta de sòls àcids amb un elevat contingut de matèria orgànica a l’horitzó superficial (0-5 cm) i majoritàriament tenen humus de tipus moder. Això fa que aquest tingui valors de nitrogen total elevats. Gràcies al pH àcid i els continguts de potassi, calci i magnesi tindrem una bona fertilitat ja que la solubilitat i assimilació dels nutrients del sòl serà bona. Tots els valors obtinguts disminueixen en profunditat i mostren una gran variabilitat entre les parcel•les estudiades.

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Entrevista con el Dr. Jordi Sabater Pi, presidente honorífico de la Asociación Interuniversitaria para la Defensa de losAnimales (AIUDA) y persona destacada no sólo como científico y pionero en el estudio de los primates superiores sino también por su compromiso en la defensa de los derechos de los animales.

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HIV-1 diagnosis is usually based on the detection of specific antibodies, appearing in a time-determined pattern following the infection. We describe a prolonged HIV-1 seroconversion in an elite controller (defined as having HIV-1 RNA persistently <50copies/ml while untreated). HIV-1 diagnosis was delayed and complicated by this atypical evolution.

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BACKGROUND: Occupational diisocyanate-induced extrinsic allergic alveolitis (EAA) is a rare and probably underestimated diagnosis. Two acute occupational EAA cases have been described in this context, but neither of them concerned hexamethylene diisocyanate (HDI) exposure. AIMS: To investigate the cause of a life-threatening EAA arising at work in a healthy 30-year-old female paint quality controller. METHODS: Occupational medical assessment, workplace evaluation, airborne and biological monitoring and immunodermatological tests. RESULTS: Diagnosis of EAA relied on congruent clinical and radiological information, confirmed occupational HDI exposure and positive IgG antibodies and patch tests. The patient worked in a small laboratory for 7 years, only occasionally using HDI-containing hardeners. While working with HDI for 6 h, she developed breathlessness, rapidly progressing to severe respiratory failure. Workplace HDI airborne exposure values ranged from undetectable levels to 4.25 p.p.b. Biological monitoring of urinary hexamethylene diamine in co-workers ranged from <1.0 to 15.4 μg/g creatinine. Patch tests 8 months later showed delayed skin reaction to HDI at 48 h. Subsequent skin biopsy showed spongiotic dermatitis with infiltration of CD4(+) and CD8(+) T cells. CONCLUSIONS: We believe this is the first reported case of acute life-threatening EAA following exposure to HDI. Low concentrations of airborne HDI and relatively high urinary hexamethylene diamine suggest significant skin absorption of HDI could have significantly contributed to the development of this acute occupational EAA.

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Type 1 diabetic patients depend on external insulin delivery to keep their blood glucose within near-normal ranges. In this work, two robust closed-loop controllers for blood glucose regulation are developed to prevent the life-threatening hypoglycemia, as well as to avoid extended hyperglycemia. The proposed controllers are designed by using the sliding mode control technique in a Smith predictor structure. To improve meal disturbance rejection, a simple feedforward controller is added to inject meal-time insulin bolus. Simulations scenarios were used to test the controllers, and showed the controllers ability to maintain the glucose levels within the safe limits in the presence of errors in measurements, modeling and meal estimation

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This paper presents a control strategy for blood glucose(BG) level regulation in type 1 diabetic patients. To design the controller, model-based predictive control scheme has been applied to a newly developed diabetic patient model. The controller is provided with a feedforward loop to improve meal compensation, a gain-scheduling scheme to account for different BG levels, and an asymmetric cost function to reduce hypoglycemic risk. A simulation environment that has been approved for testing of artificial pancreas control algorithms has been used to test thecontroller. The simulation results show a good controller performance in fasting conditions and meal disturbance rejection, and robustness against model–patient mismatch and errors in mealestimation

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Among the variety of road users and vehicle types that travel on U.S. public roadways, slow moving vehicles (SMVs) present unique safety and operations issues. SMVs include vehicles that do not maintain a constant speed of 25 mph, such as large farm equipment, construction vehicles, or horse-drawn buggies. Though the number of crashes involving SMVs is relatively small, SMV crashes tend to be severe. Additionally, SMVs can be encountered regularly on non-Interstate/non-expressway public roadways, but motorists may not be accustomed to these vehicles. This project was designed to improve transportation safety for SMVs on Iowa’s public roadway system. This report includes a literature review that shows various SMV statistics and laws across the United States, a crash study based on three years of Iowa SMV crash data, and recommendations from the SMV community.