Identification of the class of initial data for the insensitizing control of the heat equation

This paper is devoted to analyze the class of initial data that can be insensitized for the heat equation. This issue has been extensively addressed in the literature both in the case of complete and approximate insensitization (see[19] and[1], respectively). But in the context of pure insensitization there are very few results identifying the class of initial data that can be insensitized. This is a delicate issue which is related to the fact that insensitization turns out to be equivalent to suitable observability estimates for a coupled system of heat equations, one being forward and the other one backward in time. The existing Carleman inequalities techniques can be applied but they only give interior information of the solutions, which hardly allows identifying the initial data because of the strong irreversibility of the equations involved in the system, one of them being an obstruction at the initial time t = 0 and the other one at the final one t = T. In this article we consider different geometric configurations in which the subdomains to be insensitized and the one in which the external control acts play a key role. We show that, under rather restrictive geometric restrictions, initial data in a class that can be characterized in terms of a summability condition of their Fourier coefficients with suitable weights, can be insensitized. But, the main result of the paper, which might seem surprising, shows that this fails to be true in general, so that even the first eigenfunction of the system can not be insensitized. This result is similar to those obtained in the context of the null controllability of the heat equation in unbounded domains in[14] where it is shown that smooth and compactly supported initial data may not be controlled. Our proofs combine the existing observability results for heat equations obtained by means of Carleman inequalities, energy and gaussian estimates and Fourier expansions

A hardware library for sensors/actuators interfaces in sensor networks

Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. J. Portilla, J. L. Buron, T. Riesgo, and A. de Castro, "A hardware library for sensors/actuators interfaces in sensor networks", and 13th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2006, Nice (France), 2006, pp. 1244 - 1247.Sensor networks have reached a great relevance during the last years. The idea is to use a high number of nodes measuring different physical parameters in several environments, which implies different research challenges (low power consumption, communication protocols, platform hardware design, etc). There is a tendency to use modular hardware nodes in order to make easier rapid prototyping as well as to be able to redesign faster and reuse part of the hardware modules. One of the main obstacles for rapid prototyping is that sensors present heterogeneous interfaces. In this paper, a VHDL library for sensors/actuators interfaces is proposed in order to have a set of different sensor interfaces that include the most common in the sensors/actuators world, enabling a rapid connection to a new sensor/actuator

Interior comfort regulation with gypsum plasters

In this work, the performance of a manually applied thin layer of a multilayer gypsum plaster system, for interior lining of walls and ceilings, incorporating phase change materials (PCM), is investigated. The study aims the development of a passive solar storage system that can be combined with both active heating and cooling storage systems and equipments. Mechanical and thermal tests were carried in laboratory, in two test cells and in residential buildings. Results so far showed that the gypsum plaster with 20%-wt. PCM reduces up to 45-50% flexural and compressive strengths, but the specifications of the European standard for these materials are fulfil. On what concerns thermal properties, the use of gypsum-PCM plaster reduces the maximum room temperature up to 5 ºC with a time delay of 3 hours and increases the minimum room temperature up to 1.5 ºC with a time delay of 2 hours. Besides, it also reduces room relative humidity up to 10%. Power savings of 0.44 W/m2wall.m2floor were estimated, with higher potential for lower temperatures, according to tests carried in a Passy’s test cell during the cooling season.Agência de Inovação (ADI

Properties of gypsum-PCM based mortars for interior plastering of construction systems

Incorporating phase change materials (PCM) in plasters is an effective solution both for more efficient use of energy and its consumption reduction, because it allows the use of free energy in the environment, by latent heat storage. As PCM has not binder properties, it is expected to decrease mechanical properties of the final mortar. Also the density of the mortar decreases due to PCM lighter specific weight. In order to be used as a final coat for wall plastering, it must verify the requirements of the respective European Standard. This paper presents the results of the composition development and mechanical properties (flexural, compressive and adhesive strengths) testing and validation of three different gypsum mortars, in order to select the appropriate one for thermal testing in test cells. The results show that the effective decrease in the studied characteristics of the mortar does not inhibit the use for plastering, as requirements are achieved by the three studied compositions.Agência de Inovação (ADI

Ejercicio físico y estilo de vida sedentario: consecuencias para la salud

Perhaps the greatest barriers for achieving major advances in public health in the twenty-first century result from the paralysis of the pandemic paradigm or from the widespread inability to envision alternative or new models of thought. Human movement represents a complex behavior that is influenced by personal motivation, health and mobility problems, genetic factors, and social and physical environments in which people live. These factors influence the propensity to engage in sedentary behaviors or in physical activity. However, the biological, social, and environmental pathways leading to sedentary behavior versus physical activity may be different. In addition, the health effects associated with sedentary behavior and physical activity may be the result of different biological mechanisms. Thus, our objective was to discuss the importance of physical exercise on health-related outcomes and the consequences of sedentary lifestyles. Research on sedentary behavior has been growing;however, the evidence for its determinants is relatively sparse. More studies are needed to obtain more conclusive results because it is fundamental to understand these complex relationships related to the practice and the acquisition of active and healthy lifestyles as opposed to a sedentary lifestyle.info:eu-repo/semantics/publishedVersio

Benefits and difficulties of the national service training program in Rizal Technological University

The primary purpose of this study is to ascertain the benefits of the National Service Training Program (NSTP) implementation and to identify the problems encountered by its implementers. Results showed that the benefits derived from the program were topped by enhancement of skills on basic leadership with emphases on the ability to listen and ability to communicate which were rated very important and very much benefited among other training aspects of the program. Results also revealed that students are aware of the importance of physical, mental and social health as well as the observance of proper hygiene for overall sense of well-being. Although recreation is one aspect that the respondents find important, appreciation of it underscores the need to have more time for assignments and projects as most of the respondents are enrolled in their respective courses with 29 units, making them unable to appreciate the perks of involving themselves into various recreational activities. Problems in the implementation showed lack of provision of materials and equipment and of budgetary allocation which rendered full implementation weak as students and faculty involved in the community immersion have to rely on their own resources, in addition to the indifference and passivity of the local government officials. Based on the findings, the researchers recommended that: the school administrators need to allocate adequate budget for materials and equipment; periodic faculty development trainings and; to look into the passive attitude of the local officials to ensure that implementation NSTP projects will benefit both clients and implementers

Inferring resilience to fragmentation-induced changes in plant communities in a semi-arid Mediterranean ecosystem

Predicting the capacity of ecosystems to absorb impacts from disturbance events (resilience), including land-use intensification and landscape fragmentation, is challenging in the face of global change. Little is known about the impacts of fragmentation on ecosystem functioning from a multi-dimensional perspective (multiple traits). This study used 58 500-m linear transects to quantify changes in the functional composition and resilience of vascular plant communities in response to an increase in landscape fragmentation in 18 natural scrubland fragments embedded within a matrix of abandoned crop fields in Cabo de Gata-Níjar Natural Park, Almería, Spain. Changes in functional community composition were measured using functional diversity indices (functional richness and functional dispersion) that were based on 12 plant traits. Resilience was evaluated using the functional redundancy and response diversity from the perspective of plant dispersal, which is important, particularly, in fragmented landscapes. Scrubland fragmentation was measured using the Integral Index of Connectivity (IIC). The functional richness of the plant communities was higher in the most fragmented scrubland. Conversely, the functional dispersion (i.e., spread) of trait values among species in the functional trait space was lower at the most fragmented sites; consequently, the ecological tolerance of the vegetation to scrubland fragmentation decreased. Classifying the plant species into four functional groups indicated that fragmentation favoured an increase in functional redundancy in the 'short basal annual forbs and perennial forbs' group, most of which are species adapted to degraded soils. An assessment based on the traits associated with plant dispersal indicated that the resilience of 'woody plants ', an important component in the Mediterranean scrubland, and habitat fragmentation were negatively correlated; however, the correlation was positive in the 'short basal annual forbs and perennial forbs ' and the 'grasses' groups. © 2015 de Frutos et al.We are grateful to Beatriz Bueno, Elena Lahoz, Benjamin Komac, and Virginia Pascual for assisting with the collection of field data. We thank Luis Villar for his help in translating the biological types. María Felipe, Maite Gartzia, Bruce MacWhirter, and two referees provided critical comments and helpful suggestions on the manuscript.Peer Reviewe