Dynamics of gyrostat satellite subject to gravitational torque: Investigation of equilibria

Dynamics of gyrostat satellite moving along a circular orbit in the central Newtonian gravitational field is investigated. A symbolic-numerical method for determining all equilibrium orientations of gyrostat satellite in the orbital coordinate system with given gyrostatic torque and given principal central moments of inertia is proposed. Conditions of equilibriums existence are obtained depending on four dimensionless parameters of the system. All bifurcational values of parameters at which there is a change of numbers of equilibrium orientations are determined. Evolution of domains in the space of parameters which correspond to various numbers of equilibria are carried out in detail. Relationship with axisymmetrical cases of satellite gyrostat is considered. It is shown that the number of equilibria of the gyrostat satellite in general case not be less than 8 and not more than 24.Исследована динамика спутника-гиростата, движущегося в центральном ньютоновом силовом поле по круговой орбите. Предложен метод определения всех положений равновесия спутника-гиростата в орбитальной системе координат при заданных значениях вектора гиростатического момента и главных центральных моментов инерции и получены условия их существования в зависимости от четырех безразмерных параметров системы. Найдены бифуркационные значения параметров, при которых изменяется число положений равновесия. Проведен детальный численный анализ эволюции областей существования различного числа равновесий в пространстве безразмерных параметров. Рассмотрена взаимосвязь полученных областей существования с областями существования равновесий осесимметричного спутника. Показано, что число положений равновесия спутника-гиростата в общем случае не превышает 24 и не может бытьменьше 8.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio

Hotel Green Implementation for Future

The online hotel management system was designed for the client hotel green, colombo, sri lanka. Currently, the client uses a manual system for management purposes where employees handle large amounts of data manually. The proposed system allows users to store and manipulated all the data in their database making their data handling process very effective. The proposed system is developed to cover the process of the hotel such as employee management, resource management, food management, rooms management, and user account management. The admin adds and updates the available rooms and foods, and customers can check the available rooms and order foods through the system. Admin adds, updates, and deletes employee details. Admin can mark the attendance of the employees. Admin can search relevant details. Admin can view details of all customers. The customers register and log in to the system.  Customers can update and delete their accounts. A web application was developed to ensure that the customers of the hotel can make orders and reservations online. The system reduces data manipulation errors in the current process, resulting in considerable development in human resource utilization. It improves the client's relationship with their customers gaining profit for the business. The system is user-friendly, reliable, and efficient and its statistics all the customer requirements

Bolivianos Em São Paulo: Entre O Sonho E A Realidade

This paper aims to analyze the settlement of Bolivian immigrants in São Paulo, focusing on the difficulties they face in their trajectories in the city, as well as on their strategies for economic mobility and social recognition, which are developed in an adverse environment characterized by lack of proper documentation and by racial and social discrimination. © 2006 Instituto de Estudos Avançados da Universidade de São Paulo.2057157170Harvey, D., (1992) Condição Pós-moderna, , São Paulo: LoyolaFrugoli Jr., H., (1995) São Paulo: Espaços Públicos E Integração Social, , São Paulo: Marco ZeroLe Goff, J., (1994) O Imaginário Medieval, , Lisboa: EstampaMagnani, J.G.C., Torres, L.deL., (1996) Na Metrópole, , (Org.) São Paulo: EduspPóvoa Neto, H., A criminalização das migrações na nova ordem internacional (2005) Cruzando Fronteiras Disciplinares. Um Panorama Dos Estudos Migratórios, pp. 297-309. , In: PÓVOA NETO, H.FERREIRA, A. P. (Org.) Rio de Janeiro: RevanSales, T., (1999) Brasileiros Longe De Casa, , São Paulo: CortezSayad, A., (1998) A Imigração Ou Os Paradoxos Da Alteridade, , São Paulo: EduspSayad, A., O retorno: Elemento constitutivo da condição do imigrante (2000), Travessia - Revista do Migrante, São Paulo, Centro de Estudos Migratórios, n.1, especial, janeiroSilva, S., A Costurando sonhos. Trajetória de um grupo de imigrantes bolivianos em São Paulo (1997), São Paulo: PaulinasSilva, S., Virgem/Mãe/Terra. Festas e tradições bolivianas na metrópole (2003), São Paulo: Hucitec, FapespSilva, S., Bolivianos. A presença da cultura andina (2005), São Paulo: LazuliSilva, S., A praça é nossa. Faces do preconceito num bairro paulistano (2005) Travessia - Revista Do Migrante, São Paulo, Centro De Estudos Migratórios, (51)Ugarte, A.S., Margens míticas: A Amazônia no imaginário europeu do século XVI (2003) Os Senhores Dos Rios, , In: DEL PRIORY, M.GOMES, F. (Org.) Rio de Janeiro: Campu

Effect of replacing wheat bran with spineless cactus plus urea in sugarcane-based diets for sheep

In times of drought, the availability of feed is reduced, and the use of concentrate ingredients, such as wheat bran, becomes costly for animal production. Thus, the use of spineless cactus emerges as a potential solution to the shortage of feed and water during prolonged drought periods. The objective of this study was to evaluate the effects of replacing wheat bran with spineless cactus plus urea (0%, 25%, 50%, 75%, and 100%) in sugarcane-based diets for sheep on nutrient intake, feeding behaviour, nitrogen balance and microbial protein synthesis. Five male Santa Ines sheep with average initial bodyweight of 34.0 ± 3.6 kg were used in a 5 × 5 Latin square. The maximum intakes of dry matter (DM) (1414 g/day), organic matter (OM) (1281 g/day), crude protein (CP) (204 g/day), neutral detergent fibre corrected for ash and protein (NDFap) (425 g/day), and total digestible nutrients (TDN) (890 g/day) were estimated with replacement levels of 80.2%, 75.3%, 88.6%, 50.5%, and 79.3% respectively. Feeding behaviour was not altered by replacing wheat bran with spineless cactus plus urea. Nitrogen retention increased by 0.10 g/day, while plasmatic urea nitrogen increased by 0.20 mg/day for every 1% level of replacement. The maximum production of microbial nitrogen (15.9 g/day) and microbial protein synthesis (99.4 g/day) were estimated with replacement levels of 45.8 and 45.7%, respectively. It is concluded that up to 80% wheat bran could be replaced with spineless cactus plus urea in sugarcane-based diets for sheep.Keywords: Alternative feed, drought, feeding behaviour, intake, microbial protei

Effects of low intensity ultrasound on the germination of corn seeds (Zea mays L.) under different water availabilities

The effects of low intensity ultrasound on the performance of corn seeds (Zea mays L.), were investigated at two intensity levels, 230 and 175 mW/m². This study analysed the ultrasound effects on the germination under different water availabilities. The emergence and development of embryonic structures do react proportionally to the water availability and the treatment with ultrasound has no pronounced influency on the phenomena related to seed germination. However, a tendency of positive interference of this treatment in the seedling development in hidrie deficiency situations is detectable.Foram estudados os efeitos do ultra-som de baixa intensidade (230 e 1750 W/m²) sobre o desempenho de sementes de milho (Zea mays L.) utilizando situações variáveis quanto à disponibilidade hídrica. A emergência e o desenvolvimento de estruturas embrionárias reagem proporcionalmente à disponibilidade de água, não havendo influência marcante do tratamento com ultra-som nos fenômenos envolvidos na germinação das sementes. Contudo, são detectáveis tendências indicadoras de interferência positiva desse tratamento no desenvolvimento das plántulas em situações de deficiência hídrica

Highly conductive p-type nanocrystalline silicon films deposited by RF-PECVD using silane and trimethylboron mixtures at high pressure

In this paper we present a study of boron-doped nc-Si:H films prepared by PECVD at high depositionpressure (>4 mbar), high plasma power and low substrate temperature (7 (U cm)1) andhigh optical band gap (>1.7 eV). Modeling of ellipsometry spectra reveals that the film growth mechanismshould proceed through a sub-surface layer mechanism that leads to silicon crystallization.The obtained films are very good candidates for application in amorphous and nanocrystalline siliconsolar cells as a p-type window layer.Peer reviewe

Spin separation in digital ferromagnetic heterostructures

In a study of the ferromagnetic phase of a multilayer digital ferromagnetic semiconductor in the mean-field and effective-mass approximations, we find the exchange interaction to have the dominant energy scale of the problem, effectively controlling the spatial distribution of the carrier spins in the digital ferromagnetic heterostructures. In the ferromagnetic phase, the majority and minority carriers tend to be in different regions of the space (spin separation). Hence, the charge distribution of carriers also changes noticeably from the ferromagnetic to the paramagnetic phase. An example of a design to exploit these phenomena is given.Comment: 4 pages, 3 figures. Submitted to Phys. Rev.