14 research outputs found
Exploiting the reciprocal channel for discrete jamming to secure wireless communications against multiple-antenna eavesdropper
The purpose of this paper is to advance the current state of physical layer security through
the design and analysis of a discrete jamming scheme that exploits the reciprocal characteristic of the
wireless channel with the aim to create equivocation to a passive multiple-antenna eavesdropper. Closed form
solutions of the secrecy capacity for different configurations of the jamming component were obtained and
successfully compare with the simulation results. Furthermore, the secrecy level provided by the developed
scheme is analyzed taking into account the number of bits extracted from the channel. The asymptotic study
of the proposed secrecy technique allowed to conclude that in the high-power regime, full secrecy is obtained
even considering that the eavesdropper is equipped with an unlimited number of antennas.publishe
Effectiveness of the European Natura 2000 network at protecting Western Europe’s agro-steppes
Assessing progress towards achieving conservation targets is a requirement for all countries committed to the Convention on Biological Diversity. The Natura 2000 network is the largest protected area network in the world and was created to protect Europe’s threatened species and habitats, often requiring active management. This study assesses the effectiveness of areas classified under the EU Birds Directive at protecting Western Europe’s agro-steppes, the last remnants of suitable habitat for several endangered bird species. We quantify agro-steppe habitat change in the last 10 years using high-resolution aerial images of 21 Special Protection Areas and surrounding areas. The selected SPAs hold one third of the global population of great bustards Otis tarda , a flagship conservation species. Agro-steppe area losses occurred across all sites surveyed but were 45% lower inside Natura 2000 compared to non-protected areas. Natura 2000 sites still lost over 35 000 ha of agro-steppe habitat in 10 years, an area that could hold approximately 500 great bustards. These low yield farmlands are being converted predominately to permanent and irrigated crops. At the current rate of habitat conversion, agro-steppes could be reduced to 50% of the present area during the next century. Moreover, the greater conversions outside protected sites may transform the remaining agro-steppes into isolated “islands” with low population connectivity. Our study on agro-steppes illustrates the relevant contribution of Natura 2000 at protecting Europe’s key habitats, but also highlights crucial insufficiencies that still need to be addressed to achieve the CBD conservation targets and halt biodiversity loss
Assessment of nutritional status of oncology patients at hospital admission : A Portuguese real-world study
BackgroundNutritional status in patients with cancer has a determining role in the evolution of the disease and tolerance to treatments. Severity of undernutrition impacts morbidity and mortality in cancer patients and can limit patient response to the optimal therapies if nutritional issues are not appropriately addressed and managed. Despite the importance of malnutrition for the clinical evolution of oncology patients, there is not yet a universally accepted standard method for evaluating malnutrition in such patients. The aim of this study was to stratify the nutritional status of inpatients at an Oncology Department. MethodsThis is an observational study with 561 cancer patients, assessed at admission to a Medical Oncology Department from November 2016 to February 2020. All patients were considered eligible. Non-compliant and/or comatose patients were excluded. Nutritional status was assessed using the PG-SGA, BMI classified with the WHO criteria, and calculation of the percentage of weight loss in the previous 3-6 months. ResultsA total of 561 patients (303 F: 258 M; mean age 65 +/- 13 years) were included. One-third of the patients, n=191/561 (34%), lost 6% of their weight in the month prior to admission and 297/561 (53%) patients lost 10.2% of weight in the previous 6 months. Mean BMI was 24.1 +/- 5.8 kg/m(2); N = 280/561 (50%) patients had regular BMI according to the WHO criteria. N = 331/561 (59%) patients reported eating less in the month prior to admission. N = 303/561 (54%) had moderate/severe deficits of muscle and adipose compartments. The PG-SGA identified 499/561 (89%) patients as moderately/severely malnourished, of which 466/561 (83%) patients scored >= 9 points, meeting criteria for a critical need for nutritional support. Fifteen percent of patients scored >4 points, indicating a need for directed therapy for symptom control and only 1% scoredPeer reviewe
LusĂmetro Digital de medida em percentagem
Este lusĂmetro, tal como outros circuitos de laboratĂłrio, foi elaborado
inicialmente para os antigos dias da UBI (1997-2011).
Posteriormente foram usados nas semanas de promoção e divulgação da UBI
(2012 – 2013).
Ultimamente foram remontados com melhor performance e aspecto, sendo
usados na Academia JĂşnior das CiĂŞncias (2014 - dias de hoje).
Estes circuitos cientĂfico – pedagĂłgicos tĂŞm tambĂ©m sido usados nos Dias da
CiĂŞncia Viva, Semana das CiĂŞncias e Escolas de VerĂŁo.
Estes projectos utilizam uma boa variedade de componentes dos laboratĂłrios de
ElectrĂłnica, Sistemas Digitais e Electromagnetismo, criando protĂłtipos cientĂficopedagĂłgicos
reais à disposição da comunidade (júnior, universitária e sénior).
Este trabalho mostra o lusĂmetro digital de medida em percentagem de 0% a 99%.
Foi aferido de modo a que 0% corresponde ao escuro e 99% Ă luz solar directa.
Este lusĂmetro digital que se mostra na Fig.1, tal como outros aparelhos de
medida, Ă© constituĂdo pelo sensor LDR 5mm, depois o calibrador Ă© o AmpOp
TL081 com ganho ajustado, depois a ADC 0804 converte a intensidade luminosa
analógica, na correspondente digital binário natural. Depois há o conversor
binário natural de 8 bits para BCD de 8 bits, baseado numa PLD22V10. Depois
temos 2 conversores de BCD para 7 segmentos. Depois temos 2 packs de 8
resistĂŞncias de 1k. Depois temos 2 displays de 7 segmentos com ponto decimal.
Este lusĂmetro foi montado no laboratĂłrio de ElectrĂłnica do dep. FĂsica da UBI.
Possui um boa configuração e estabilidade, que é semelhante aos modelos
comerciais.
Este protĂłtipo laboratorial pode ser tomado como referĂŞncia pelos alunos, que
estĂŁo projectando modelos laboratoriais semelhantes.Universidade da Beira Interiorinfo:eu-repo/semantics/publishedVersio
TermĂłmetro Digital de medida em Graus Celsius
Este termĂłmetro digital, tal como muitos outros circuitos montados, foi elaborado
inicialmente para os antigos dias da UBI (1997-2011).
Posteriormente foram usados nas semanas de promoção e divulgação da UBI
(2012 – 2013).
Ultimamente foram remontados com melhor aspecto e performance, sendo
usados na Academia JĂşnior das CiĂŞncias (2014 - dias de hoje).
Estes projectos cientĂfico – pedagĂłgicos tĂŞm tambĂ©m sido usados nos Dias da
CiĂŞncia Viva, Semana das CiĂŞncias e Escolas de VerĂŁo.
Estes projectos proporcionam, que diversos componentes do laboratĂłrio de
Electrónica e Sistemas Digitais criem protótipos reais, à disposição da
comunidade (júnior, universitária e sénior).
Este trabalho mostra o termĂłmetro digital aferido em graus celsius (ÂşC), possui
uma escala de 0ºC a 255ºC e resolução de 1ºC.
Este termĂłmetro digital, que se mostra na Fig.1, tal como outros tipos de
termĂłmetro, Ă© constituĂdo pelo sensor, neste caso o LM35. Depois o calibrador Ă© o
AmpOP TL081 com o ganho ajutado. Depois a ADC0804 converte a tensĂŁo/
temperatura analógica na correspondente digital binário natural de 8bits. Depois
há o conversor binário natural 8 bits para BCD 10 bits (3 displays) baseado na
PLD22V10. Depois temos 3 conversores de BCD para 7 segmentos, 3 packs de 8
resistĂŞncias de 1k e 3 displays de 7 segmentos com ponto decimal.
Este termĂłmetro foi montado no laboratĂłrio de ElectrĂłnica do dep. FĂsica da UBI.
Possui uma boa configuração e estabilidade semelhante aos modelos comerciais.
Este protĂłtipo laboratorial pode ser tomado como referĂŞncia pelos alunos, que
estĂŁo fazendo projectos semelhantes.Universidade da Beira Interiorinfo:eu-repo/semantics/publishedVersio
En quoi « le métabolisme territoriale » permet de repenser l’élevage ?
En quoi « le métabolisme territoriale » permet de repenser l’élevage ? . 23. Rencontres Recherches Ruminant
Intérêts et limites de la méthode du métabolisme territorial pour analyser les flux de matière et d’énergie dans les territoires d’élevage
Aujourd’hui, pour maintenir un niveau élevé de production tout en diminuant les impacts environnementaux, il est essentiel de comprendre finement les interactions entre activités d’élevage et flux de matière à l’échelle des exploitations et des territoires. Pour cela, le métabolisme territorial, méthode d’évaluation systémique et multicritère semble prometteuse. Le métabolisme territorial analyse qualitativement et quantitativement le transfert, le stockage et la transformation de matière au sein d’un territoire. Cet inventaire situé dans l’espace et le temps permet donc d’analyser conjointement des processus naturels et techniques. Enfin, en quantifiant l’exploitation des ressources, la production de biens et de déchets, cette méthode permet de calculer simultanément différentes efficiences productives et d’identifier des leviers d’action (substitution, bouclages de cycle, ...). Le métabolisme de l’élevage français, de 1938 à 2010, est analysé pour illustrer l’approche. Il montre que l’augmentation conjointe de la productivité et de l’efficacité de conversion de l’élevage, s’accompagne d’une perte d’autonomie et d’une augmentation des concurrences homme-animal. Les productions de ruminants offrent des avantages clés en termes d’autonomie protéique et de concurrence entre ressources consommables par l’homme.Today, to maintain a high level of production while decreasing environmental impacts, it is essential to understand the interactions between livestock and material flow across farms and territories. For this, the socio-ecological metabolism (SEM), a method of systemic assessment and multi-criteria seems promising. The SEM analyzes qualitatively and quantitatively the transfer, storage and material processing within a territory. This inventory located in space and time allows a joint assessment of natural and technical processes. By quantifying resource, production of goods and waste, the SEM method calculates simultaneously different production efficiencies and identifies levers of actions (better closing of the nutrient cycle, input substitution, ...). The SEM of the French livestock sector, from 1938 to 2010 was analyzed to illustrate the approach. It revealed an increased productivity and conversion efficiency of livestock, accompanied by a loss of self-sufficiency and increased feed / food competition. Ruminant productions present key advantages in terms of self-sufficiency and feed/food competition
Trends of material flow accounts in the Brazilian livestock sector: insights and prospects for research development
Trends of material flow accounts in the Brazilian livestock sector: insights and prospects for research development. 4. SimpĂłsio de Sustentabilidade & CiĂŞncia Anima
Livestock farming system diversity and resource use efficiency: What the history tells for France?
Livestock farming system diversity and resource use efficiency . What the history tells for France?. 67. Annual meeting of the European Federation of Animal Science EAAP 201
Exploring trade-offs among indicators of performance and environmental impact in livestock areas
Assessing the sustainability of livestock production involves understanding trade-offs among indicators of performance and environmental impact at multiple levels (i.e. animal, farm, regional, global). To date, most studies have focused on animal/farm levels. There is a need to move towards a regional level where several livestock species and plant resources combine, along with biophysical and socioecological characteristics. The objective of this study was (i) to assess the performance and environmental impact across livestock-dominated areas in France and (ii) to identify and explore trade-offs among performance/impact indicators. A set of indicators was derived from an inventory of nitrogen (N) flows computed across 48 French departments. Analysis of indicator relationships revealed trade-offs for which spatial decomposition was mapped. At the level of the 48 departments, gains in livestock N use efficiency and animal source food production often compromised other dimensions: N surplus and N self-sufficiency. These trade-offs suggested how unlikely are simultaneous gains in provision of animal source food and low environmental impact (i.e. decreased N surplus). The spatial decomposition of trade-offs showed that a few areas achieved moderate levels of animal source food at high livestock N use efficiency and high N self-sufficiency, along with low levels of environmental impacts (low N surplus and low N excretion emissions). These findings highlight the importance of areas emphasizing grazing, where livestock transforms human-inedible resources into high-quality animal source food with high production performance and low environmental impact. Our results show that improvement of sustainability requires a solution for the regional level in complement to the farm level