A State-Machine Model for Reliability Eliciting over Wireless Sensor and Actuator Networks

AbstractAdvances in communications and embedded systems have led to the proliferation of wireless sensor and actuator networks (WSANs) in a wide variety of application domains. One important key of many such WSAN applications is the needed to meet non-functional requirements (e.g., lifetime, reliability, time guarantees) as well as functional ones (e.g. monitoring, actuation). Some application domains even require that sensor nodes be deployed in harsh environments (e.g., refineries), where they can fail due to communication interference, power problems or other issues. Unfortunately, the node failures can be catastrophic for critical or safety related systems. State machines can offer a promising approach to separate the two concerns – functional and non-functional – bringing forth reliability exception conditions handling, by means of fault handling states. We develop an approach that allows users to define and program typical applications using their platform language, but also adds state machine logic to design, view and handle explicitly other concerns such as reliability. The experimental section shows a working deployment of this concept in an industrial refinery settin

Software-based security approach for networked embedded devices

As the Internet of Things (IoT) continues to expand, data security has become increasingly important for ensuring privacy and safety, especially given the sensitive and, sometimes, critical nature of the data handled by IoT devices. There exist hardware-based trusted execution environments used to protect data, but they are not compatible with low-cost devices that lack hardware-assisted security features. The research in this paper presents software-based protection and encryption mechanisms explicitly designed for embedded devices. The proposed architecture is designed to work with low-cost, low-end devices without requiring the usual changes on the underlying hardware. It protects against hardware attacks and supports runtime updates, enabling devices to write data in protected memory. The proposed solution is an alternative data security approach for low-cost IoT devices without compromising performance or functionality. Our work underscores the importance of developing secure and cost-effective solutions for protecting data in the context of IoT.Comment:

CityMii - An integration and interoperable middleware to manage a Smart City

Modern cities are supported by multiple heterogeneous IT systems deployed and managed by distinct agents. In general, those systems use old, dependent and non-standardized technologies, which make them legacy and incompatible systems. As smart cities are moving toward a fully centralized management approach, the lack of integration among systems raises several problems. Since they are independent, it is not easy to correlate information from different systems and put it together to work in order to achieve application goals. The collaboration among different systems enables an agent to offer new functionalities (services or just information about the city) that cannot be provided by any of these systems working as individual entities. The goal of this paper is to propose an integration middleware to support the management of Smart Cities in a dynamic, transparent and scalable way. The proposed middleware intends to support interoperability among different systems operating in a city.info:eu-repo/semantics/publishedVersio

Denoising Autoencoder-based Defensive Distillation as an Adversarial Robustness Algorithm

Adversarial attacks significantly threaten the robustness of deep neural networks (DNNs). Despite the multiple defensive methods employed, they are nevertheless vulnerable to poison attacks, where attackers meddle with the initial training data. In order to defend DNNs against such adversarial attacks, this work proposes a novel method that combines the defensive distillation mechanism with a denoising autoencoder (DAE). This technique tries to lower the sensitivity of the distilled model to poison attacks by spotting and reconstructing poisonous adversarial inputs in the training data. We added carefully created adversarial samples to the initial training data to assess the proposed method's performance. Our experimental findings demonstrate that our method successfully identified and reconstructed the poisonous inputs while also considering enhancing the DNN's resilience. The proposed approach provides a potent and robust defense mechanism for DNNs in various applications where data poisoning attacks are a concern. Thus, the defensive distillation technique's limitation posed by poisonous adversarial attacks is overcome.Comment: This paper have 4 pages, 3 figures and it is accepted at the Ada User journa

Improving bluetooth beacon-based indoor location and fingerprinting

The complex way radio waves propagate indoors, leads to the derivation of location using fngerprinting techniques. In this cases, location is computed relying on WiFi signals strength mapping. Recent Bluetooth low energy (BLE) provides new opportunities to explore positioning. In this work is studied how BLE beacons radio signals can be used for indoor location scenarios, as well as their precision. Additionally, this paper also introduces a method for beacon-based positioning, based on signal strength measurements at key distances for each beacon. This method allows to use diferent beacon types, brands, and location conditions/constraints. Depending on each situation (i.e., hardware and location) it is possible to adapt the distance measuring curve to minimize errors and support higher distances, while at the same time keeping good precision. Moreover, this paper also presents a comparison with traditional positioning method, using formulas for distance estimation, and the position triangulation. The proposed study is performed inside the campus of Viseu Polytechnic Institute, and tested using a group of students, each with his smart-phone, as proof of concept. Experimental results show that BLE allows having < 1.5 m error approximately 90% of the times, and the experimental results using the proposed location detection method show that the proposed position technique has 13.2% better precision than triangulation, for distances up to 10 m.info:eu-repo/semantics/publishedVersio

Agronomic characteristics of tomato genotypes ('Salad' type) during winter season, in Araguari, Minas Gerais

O trabalho foi desenvolvido em Araguari (MG), na época de inverno, com o objetivo de verificar o desempenho agronômico de genótipos de tomateiro tipo 'Salada'. Utilizou-se o delineamento experimental de blocos casualizados com 18 tratamentos e quatro repetições. As colheitas iniciaram 76 dias após o transplante, de 03/08/1996 a 05/10/1996, para a maioria dos genótipos, sendo feito um total de 18 colheitas. Como resultado os genótipos T-8, T-10, Barão Vermelho AG-561, Carmen, Agora e Olimpo superaram significativamente as demais em produtividade comercial, variando de 125,3 t/ha (Olimpo) a 142,6 t/ha (T-8), sendo portanto recomendáveis para a região, no período de inverno. Mais de 60% dos genótipos tiveram frutos com peso médio superior a 200 g, com destaque para Barão Vermelho AG-561 (259,50 g) e Sunbolt (255,75 g) que apresentaram mais de 30% de frutos do tipo extra AA, sendo superados apenas pelo genótipo Carmen, porém com padrão de fruto bem diferente em tamanho. Com mais de 44% de frutos tipo extra A destacaram-se os genótipos Super Marmande, T-8, Sunbeam e AG-233. O genótipo Agora destacou-se com frutos do tipo primeira (59,70%).A field trial was carried out in Araguari, Brazil, during the winter season, to evaluate the agronomic potential of eighteen tomato genotypes ('Salad' type). A randomized blocks design with four replications was used. A total of 18 harvests were carried out, beginning 76 days after transplanting, from August, 3rd to October, 5th, 1996. In general, the genotypes T-8, T-10, Barão Vermelho AG-561, Carmen, Agora and Olimpo presented higher yields, varying from 125.3 t/ha (Olimpo) to 142.6 t/ha (T-8). These genotypes can be cultivated in this region, during the winter season. More than 60% of the tomato genotypes presented fruits with 200 g, the outstanding one being the Barão Vermelho AG-561 (259,50 g) and Sunbolt (255,75g), with more than 30% of type extra AA. 'Carmen' was superior, indeed the fruits were very irregular in size. Genotypes Super Marmande, T-8, Sunbeam and AG-233 presented more than 44% of extra A fruits. Genotype Agora (59,70%) was outstanding, equal to the first type

Collard greens and chicory intercropping efficiency as a function of chicory (Cichorium intybus) transplant time

Vegetable intercropping has advantages over single cultivation in terms of less environmental impact. However, to convince farmers to adopt this production system, it is necessary to prove greater efficiency in the production of more food per unit area and therefore an increase in productivity. An experiment was carried out aiming to evaluate the effect of the chicory transplant time in intercrops with collard greens on crop yields and land use efficiency index (LUE). The experimental design was a randomized block, with nine treatments in a 2 × 4 + 1 factorial scheme, and four replications. Crop systems (intercrop and monoculture) and chicory transplant time (0, 14, 28 and 42 days after transplant (DAT) of collard greens) were evaluated. The collard greens yield increased as the chicory transplant time was delayed. The total and per harvest yields of chicory were not influenced by its transplant time. Regardless of chicory transplant time, collard greens and chicory intercropping provided greater LUE than their monocultures and reached the maximum value (52% higher) when the chicory was transplanted 42 days after collard greens. Highlights: The collard green yield increased by 11 kg ha-1 for each day of delay in the chicory transplant (0 to 42 days). The total and per harvest chicory yields were not influenced by its transplant time in relation to collard green transplant. The collard green and chicory intercropping provided 52% higher land use efficiency than their monocultures when the chicory was transplanted 42 days after collard green.Vegetable intercropping has advantages over single cultivation in terms of less environmental impact. However, to convince farmers to adopt this production system, it is necessary to prove greater efficiency in the production of more food per unit area and therefore an increase in productivity. An experiment was carried out aiming to evaluate the effect of the chicory transplant time in intercrops with collard greens on crop yields and land use efficiency index (LUE). The experimental design was a randomized block, with nine treatments in a 2 × 4 + 1 factorial scheme, and four replications. Crop systems (intercrop and monoculture) and chicory transplant time (0, 14, 28 and 42 days after transplant (DAT) of collard greens) were evaluated. The collard greens yield increased as the chicory transplant time was delayed. The total and per harvest yields of chicory were not influenced by its transplant time. Regardless of chicory transplant time, collard greens and chicory intercropping provided greater LUE than their monocultures and reached the maximum value (52% higher) when the chicory was transplanted 42 days after collard greens. Highlights: The collard green yield increased by 11 kg ha-1 for each day of delay in the chicory transplant (0 to 42 days). The total and per harvest chicory yields were not influenced by its transplant time in relation to collard green transplant. The collard green and chicory intercropping provided 52% higher land use efficiency than their monocultures when the chicory was transplanted 42 days after collard green

Nursing diagnoses of elderly patients using multiple drugs

Considerando que os idosos que utilizam múltiplos medicamentos são propensos à maior vulnerabilidade nas condições de saúde, propomo-nos, neste estudo: identificar os diagnósticos de enfermagem, segundo a taxonomia II de NANDA, de um grupo de idosos que utilizam cinco ou mais medicamentos. Foram selecionados 67 idosos, a partir da Avaliação Geriátrica Ampla (AGA) entre 301 residentes na área de abrangência de um Programa de Saúde da Família (PSF). Os 67 idosos apresentaram 16 categorias diagnósticas, em média 5,2 diagnósticos/idoso, sendo os mais frequentes a dor crônica, presente em 59,7% dos idosos; 58,2% têm a mobilidade física prejudicada; 47,7%, nutrição desequilibrada (mais que as necessidades corporais), e 47,7% têm um controle ineficaz do regime terapêutico. Tais diagnósticos revelam a necessidade de medidas envolvendo mudanças no estilo de vida, além do acompanhamento sistemático dessas pessoas.Considerando que los ancianos que utilizan múltiples medicamentos son propensos a una mayor vulnerabilidad en sus condiciones de salud, nos proponemos en este estudio identificar los diagnósticos de enfermería según la taxonomía II de NANDA, de un grupo de ancianos que utilizan cinco o más medicamentos. Fueron seleccionados 67 ancianos, a partir de la Avaliação Geriátrica Ampla (AGA), entre 301 residentes en el área comprendida por un Programa de Salud Familiar (PSF). Los 67 ancianos presentaron 16 categorías diagnósticas, con una media de 5,2 diagnósticos/anciano, siendo los más frecuentes el dolor crónico (afectando a un 59,7%), la movilidad física reducida (58,2%), nutrición desequilibrada -por encima de las necesidades corporales- (47,7%) y control ineficaz del régimen terapéutico (47,7%). Tales diagnósticos determinan la necesidad de medidas que implican cambios sustanciales en el estilo de vida, además del seguimiento médico sistemático de dichas personas.Considering that elderly people using multiple drugs are prone to a higher vulnerability of their health conditions, in this study we proposed to identify nursing diagnoses, according to NANDA´s taxonomy II, in a group of elderly people who use five or more drugs. Sixty-seven elderly people were selected using the Wide Geriatric Evaluation (WGE), out of 301 elderly residents from a Family Health Program (PSF) unit. All of the 67 seniors presented a total 16 diagnostic categories, an average of 5.2 diagnostics/elderly: 59.7% of them having chronic pain; 58.2% with impaired physical mobility; 47.7% with unbalanced nutrition: more than the body needs; and 47.7% have an inefficient control of the therapeutic regimen, among others. These diagnoses reveal the need for measures involving changes in lifestyle, as well as a systematic following of these elderly people

Espectroscopia de próton por ressonância magnética de lobo frontal em esquizofrênicos: revisão crítica da metodologia

Schizophrenic patients undergoing proton magnetic resonance spectroscopy show alterations in N-acetyl aspartate levels in several brain regions, indicating neuronal dysfunction. The present review focuses on the main proton magnetic resonance spectroscopy studies in the frontal lobe of schizophrenics. A MEDLINE search, from 1991 to March 2004, was carried out using the key-words spectroscopy and schizophrenia and proton and frontal. In addition, articles cited in the reference list of the studies obtained through MEDLINE were included. As a result, 27 articles were selected. The results were inconsistent, 19 papers reporting changes in the N-acetyl aspartate levels, while 8 reported no change. Methodological analysis led to the conclusion that the discrepancy may be due the following factors: (i) number of participants; (ii) variation in the clinical and demographic characteristics of the groups; (iii) little standardization of the acquisition parameters of spectroscopy. Overall, studies that fulfill strict methodological criteria show N-acetyl aspartate decrease in the frontal lobe of male schizophrenics.Pacientes esquizofrênicos submetidos à espectroscopia de próton por ressonância magnética demonstram alterações nos níveis de N-acetilaspartato em diversas regiões cerebrais, suportando a hipótese de disfunção neuronal nestas áreas. Objetiva-se apresentar uma revisão da literatura, sobre os principais estudos de espectroscopia de próton por ressonância magnética na região frontal em esquizofrênicos. Utilizou-se o indexador MEDLINE, no período entre 1991 e março de 2004, com o cruzamento dos termos spectroscopy, schizophrenia, proton e frontal. Foram selecionados 27 artigos originais, cujos resultados mostram-se discordantes quanto à alteração nos valores de N-acetilaspartato (19 artigos apresentaram alterações nos níveis de N-acetilaspartato e oito estudos não apresentam alterações). A presente revisão sugere que esta diversidade de resultados pode ser atribuída aos seguintes fatores: 1-número de participantes; 2- variação nas características clínicas e demográficas dos grupos; 3- pouca padronização dos parâmetros de aquisição dos espectros. Os artigos que satisfazem os critérios metodológicos mais rígidos sugerem diminuição de NAA no lobo frontal de esquizofrênicos do sexo masculino

Cork Oak Young and Traumatic Periderms Show PCD Typical Chromatin Patterns but Different Chromatin-Modifying Genes Expression

Plants are subjected to adverse conditions being outer protective tissues fundamental to their survival. Tree stems are enveloped by a periderm made of cork cells, resulting from the activity of the meristem phellogen. DNA methylation and histone modifications have important roles in the regulation of plant cell differentiation. However, studies on its involvement in cork differentiation are scarce despite periderm importance. Cork oak periderm development was used as a model to study the formation and differentiation of secondary protective tissues, and their behavior after traumatic wounding (traumatic periderm). Nuclei structural changes, dynamics of DNA methylation, and posttranslational histone modifications were assessed in young and traumatic periderms, after cork harvesting. Lenticular phellogen producing atypical non-suberized cells that disaggregate and form pores was also studied, due to high impact for cork industrial uses. Immunolocalization of active and repressive marks, transcription analysis of the corresponding genes, and correlations between gene expression and cork porosity were investigated. During young periderm development, a reduction in nuclei area along with high levels of DNA methylation occurred throughout epidermis disruption. As cork cells became more differentiated, whole nuclei progressive chromatin condensation with accumulation in the nuclear periphery and increasing DNA methylation was observed. Lenticular cells nuclei were highly fragmented with faint 5-mC labeling. Phellogen nuclei were less methylated than in cork cells, and in lenticular phellogen were even lower. No significant differences were detected in H3K4me3 and H3K18ac signals between cork cells layers, although an increase in H3K4me3 signals was found from the phellogen to cork cells. Distinct gene expression patterns in young and traumatic periderms suggest that cork differentiation might be under specific silencing regulatory pathways. Significant correlations were found between QsMET1, QsMET2, and QsSUVH4 gene expression and cork porosity. This work evidences that DNA methylation and histone modifications play a role in cork differentiation and epidermis induced tension-stress. It also provides the first insights into chromatin dynamics during cork and lenticular cells differentiation pointing to a distinct type of remodeling associated with cell death