13 research outputs found

    Electric Vehicles Lithium-Polymer Ion Battery Dynamic Behaviour Charging Identification and Modelling Scheme

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    Lithium-ion batteries are considered the substantial electrical storage element for electric vehicles (EVs). The battery model is the basis of battery monitoring, efficient charging, and safety management. Non-linear modelling is the key to representing the battery and its dynamic internal parameters and performance. This paper proposes a smart scheme to model the lithium-polymer ion battery while monitoring its present charging current and terminal voltage at various ambient conditions (temperature and relative humidity). Firstly, the suggested framework investigated the impact of temperature and relative humidity on the charging process using the constant current-constant voltage (CC-CV) charging protocol. This will be followed by monitoring the battery at the surrounding operating temperature and relative humidity. Hence, efficient non-linear modelling of the EV battery dynamic behaviour using the Hammerstein-Wiener (H-W) model is implemented. The H-W model is considered a black box model that can represent the battery without any mathematical equivalent circuit model which reduces the computation complexity. Finally, the model beholds the boundaries of the charging process that not affecting on the lifetime of the battery. Several dynamic models are applied and tested experimentally to ensure the effectiveness of the proposed scheme under various ambient conditions where the temperature is fixed at 40°C and the relative humidity (RH) at 35%, 52%, and 70%. The best fit using the H-W model reached 91.83% to describe the dynamic behaviour of the battery with a maximum percentage of error 0.1V which is in good agreement with the literature survey. Besides, the model has been scaled up to represent a real EV and expressed the significance of the proposed H-W model

    Nutritional Habits and Weight Status among Jazan University Students: Eating Patterns and Healthy lifestyle Assessment

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    Objectives The purposes of this study were to assess the prevalence of underweight, overweight, and obesity and to evaluate the nutritional habits, and related factors among the Students of Jazan University. Methods This cross-sectional study was carried out during the academic year 2014/2015 in Jazan University, Gizan, South West Saudi Arabia. A total of 436 students 19–25 y of age were examined. The questionnaires, including items on eating habits, lifestyle, and socio-demographic characteristics, were completed by the students. Data on weight, height were also collected.  The data were analyzed using descriptive statistics and chi-square test. Differences were considered statistically significant at P. value  < 0.05. Results The mean weight for males and females were 67.84 and 54.79 kg respectively, with significant differences between males and females (P. value <0.05). The mean BMI for all study participants was reported as 23.31 (kg/m²), also with significant difference between the males and females groups. About 45% of the students were of normal weight; the rate of obesity and underweight among students was very high (33.6% and 21.1% respectively), and their dietary habits were unhealthy. Regularity of meals was found only among (16.5% and 20.4%) males and females respectively. 83.3% of males and 95.1% of females reported eating snacks during the day. Conclusion The results of this study suggest that the prevalence of overweight and obesity were very high among the studied students. The study showed the need for health education programs on nutritional education in universities in order to increase awareness of students towards healthy eating and lifestyle. &nbsp

    Amamentação ao seio, amamentação com leite de vaca e o diabetes mellitus tipo 1: examinando as evidências Breast- feeding, bottle- feeding and the type 1 diabetes mellitus: examining the evidences

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    A etiologia do diabetes mellitus tipo 1 (DM1) envolve tanto herança genética como a exposição a fatores ambientais. Evidências de estudos epidemiológicos e experimentais sugerem que a dieta pode ser importante na etiopatogenia dessa doença. Em 1984, Borch-Johnsen e col. sugeriram, com base nos resultados de um estudo caso-controle, que o leite materno seria um fator de proteção para o DM1; esse efeito se daria devido às propriedades anti-infecciosas desse tipo de leite, ou pelo fato de que a amamentação ao seio evitaria que as crianças pudessem ser precocemente expostas a outros agentes etiológicos contidos nos substitutos do leite materno. Esses mesmos achados foram poste-riormente encontrados em diversos estudos, mas o papel do leite materno no aparecimento do DM1 ainda permanece controverso. Em 1992, Karjalainen e col., ao compararem os soros de indivíduos com e sem DM1, observaram, entre os diabéticos, altas concentrações de anticorpos anti-albumina bovina. Os autores postularam a hipótese de que a albumina bovina poderia atuar como desencadeadora do processo destrutivo das células ß do pâncreas e, conseqüentemente, do diabetes. Resultados conflitantes foram observados nas publicações que se sucederam a essa. Neste artigo, resumem-se e discutem-se os achados de diferentes pesquisadores que investigaram a importância desses fatores dietéticos para o aparecimento do DM1.<br>The aetiology of type 1 diabetes mellitus (DM1) includes genetic heritage and environmental exposure. Evidence from animal and epidemiological studies suggests that some diet components may play a role in the aetiology of DM1. In 1984, Borch-Johnsen et al. suggested, based on a case-control study, that breast-feeding was a protective factor for DM1, probably due its anti-infectious properties or because breast-feeding delays exposure to other etiologic agents in the diet. Afterwards, the same results were found in several studies but the role of breast milk in the development of DM1, is still subject to controversy. In 1992, Karjalainen et al., compared the blood serum of subjects with and without DM1 and they observed a higher concentration of anti-bovine albumin antibodies among diabetic subjects. The authors suggested that bovine albumin could act as a trigger of the destructive process of the pancreas and, in this way, lead to diabetes; discordant results have been observed in the literature since then. In this paper, we summarise and discuss the results found in different studies on dietary factors and DM1
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