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41.
CoMem: collaborative memory management for real-time operation within reactive sensor/actor networks
Marcel Baunach 《Real-Time Systems》2012,48(1):75-100
Increasing complexity and modularity of today??s WSAN applications impose demanding challenges on the system design. This especially affects real-time operation, resource sharing and dynamic memory management. Preemptive task systems are one way to retain good reactivity within dynamic environments. Yet, since memory is often too rare for static assignment, this rapidly leads to severe compositional problems among tasks with interfering and even varying requirements. We present our novel CoMem approach for maintaining high reactivity and efficient memory usage in such systems. With respect to task priorities and the typically limited resources of sensor nodes, we facilitate compositional software design by providing independently developed tasks with runtime information for yet collaborative and self-reflective memory sharing. Thereby, we require no special hardware-support like MMUs but operate entirely software-based. 相似文献
42.
43.
John F. Elliott David C. Lynch Tracy B. Braun 《Metallurgical and Materials Transactions B》1975,6(4):495-501
The analysis by Flood and Grjotheim1 of the equilibria between a metal and a fused slag utilizes the ionic behavior of the slag or salt, and it employs a reversible thermodynamic cycle. However, in the original analysis there appears to be an error in the use of free energy. A corrected treatment has been developed which involves a modest change and simplification in the original formulation. The revised analysis shows the importance of the thermodynamic behavior of ionic species in the slag, which may be nonideal. Data from the literature on slag-metal equilibria, for example: $$\left[ {Fe^{2 + } } \right] + \underline {Mn} = Fe\left( l \right) + \left[ {Mn^{2 + } } \right]$$ , are analyzed by the new formulation to obtain expressions for ratios of activity coefficients such as (γS2?/γO2?), (γMn2+/γFe2+) and [(γPO 4 3? )2/(γO2?)3] in terms of slag composition, the last two having been found to depend strongly on the oxygen-ion content of the slag. 相似文献
44.
Urinary amino acid excretion was determined in 31 leukemic patients and 29 normal individuals by rapid gas chromatographic analysis of 16 amino acids as their N-acetyl-n-propyl esters. The leukemic patients were concurrently undergoing, or had recently completed, chemotherapy. It was found that aspartic acid, threonine, and serine were of significance in distinguishing between patients "on" therapy and those "off" therapy. Patients with advanced disease have the greatest aminoaciduria, although both the normal and leukemic populations have wide individual ranges. Within both populations, men excrete a greater variety and quantity of amino acids than women. It is concluded that analysis of urinary amino acids represents a history of complex metabolic events, which is potentially useful for evaluating patient response to chemotherapy in leukemia. 相似文献
45.
The behavior of 24 children, aged 3-6 years, was recorded on video-tape. Simultaneously the ECG was recorded telemetrically. These observations were made during two pre-school educational programs lasting 90 minutes each: "Didactic games" and "Elementary music and movement program". For each child a scale was developed to show the correlation of mean heart-rate and well defined motor-activity. It was evident that the mean heart-rate was higher during the music program than during the didactic program, corresponding to the higher motor-activity. But it was found that in the didactic program the variation of the heart-rate within short intervals was higher due to the more frequent occurrence of respiratory arrhythmias. It was also seen that during the music program the children showed no signs of exertion as they did towards the end of the didactic program. Respiratory arrhythmias were not seen in children who according to the Schellong-test were classified as stable in their cardiovascular system. The arrhythmias occurred mainly when the children showed signs of fatigue. 相似文献
46.
Kammerer J.-B. Hebrard L. Hehn M. Braun F. Alnot P. Schuhl A. 《IEEE sensors journal》2004,4(3):313-321
Based on a qualitative study of the Stoner-Wohlfarth model, we point out that driving a magnetic tunnel junction (MTJ) with an alternative two-dimensional magnetic field allows to measure simultaneously two components of an external magnetic field. Only one single MTJ without a pinning layer is needed to measure both components of a magnetic field parallel to the junction plane. The response of the magnetometer does not depend on the resistance of the junction or the amplitude of its variations. A prototype has been manufactured and encouraging experimental results are presented. Sensitivities higher than 500 V/T and a noise level of 2 /spl mu/T//spl radic/Hz are reported. 相似文献
47.
T. Dalgleish and M. J. Power (see record 2004-15929-012) suggest that J. A. Lambie and A. J. Marcel's (2002) article implicitly presents a unitary view of self in emotion experience and propose that certain clinical phenomena require multiple selves. This reply summarizes Lambie and Marcel's usages of the term self and examines both Dalgleish and Power's gloss of these and their own usages. This indicates that their own central usage of the term misrepresents Lambie and Marcel and is itself an improper usage. More important, examination of the phenomena claimed to require multiple selves suggests that they do not and that Dalgleish and Power may have misread the relevant clinical literature. Finally, Lambie and Marcel's own conception of dissociative phenomena and multiple selves are outlined, and alternative approaches are sketched. In discussing the usages of the term self and interpretation of cognitive and affective disorders, this reply attempts to clarify certain confusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Marcel BaunachAuthor vitae 《Journal of Systems Architecture》2011,57(9):799-814
The increasing complexity of today’s reactive embedded applications can rapidly result in reduced real-time capabilities of the underlying hard and software. As an example for this paper we’ll refer to the specific and growing demands on the severely resource constrained sensor nodes in sensor/actuator networks (SANet). While preemptive operating systems are one way to retain acceptable reactivity within highly dynamic environments, their concurrency paradigm commonly leads to severe resource management problems, caused by the coexistence of tasks with interfering and even varying requirements. To counteract these problems, we present the novel Dynamic Hinting approach for maintaining good reactivity in typically resource constrained sensor/actuator systems by efficient combination of preemptive task scheduling and collaborative resource allocation. With respect to task priorities, our technique significantly improves classical methods for handling priority inversions (and deadlocks where required) under both short- and long-term resource allocations. Furthermore, we facilitate compositional software design by providing independently developed tasks with runtime information for yet collaborative and reflective resource sharing – e.g. by means of time-utility-functions. In many cases this even allows to reduce blocking delays as otherwise imposed by bounded priority inversion. 相似文献
49.
Hannes M. Findeisen Vivienne C. Voges Laura C. Braun Jannik Sonnenberg Dennis Schwarz Helena Krner Holger Reinecke Yahya Sohrabi 《International journal of molecular sciences》2022,23(11)
Reprogramming of metabolic pathways in monocytes and macrophages can induce a proatherosclerotic inflammatory memory called trained innate immunity. Here, we have analyzed the role of the Liver X receptor (LXR), a crucial regulator of metabolism and inflammation, in oxidized low-density lipoprotein (oxLDL)-induced trained innate immunity. Human monocytes were incubated with LXR agonists, antagonists, and oxLDL for 24 h. After five days of resting time, cells were restimulated with the TLR-2 agonist Pam3cys. OxLDL priming induced the expression of LXRα but not LXRβ. Pharmacologic LXR activation was enhanced, while LXR inhibition prevented the oxLDL-induced inflammatory response. Furthermore, LXR inhibition blocked the metabolic changes necessary for epigenetic reprogramming associated with trained immunity. In fact, enrichment of activating histone marks at the IL-6 and TNFα promotor was reduced following LXR inhibition. Based on the differential expression of the LXR isoforms, we inhibited LXRα and LXRβ genes using siRNA in THP1 cells. As expected, siRNA-mediated knock-down of LXRα blocked the oxLDL-induced inflammatory response, while knock-down of LXRβ had no effect. We demonstrate a specific and novel role of the LXRα isoform in the regulation of oxLDL-induced trained immunity. Our data reveal important aspects of LXR signaling in innate immunity with relevance to atherosclerosis formation. 相似文献
50.
Paola C. Bello-Medina Karina Corona-Cervantes Norma Gabriela Zavala Torres Antonio Gonzlez Marcel Prez-Morales Diego A. Gonzlez-Franco Astrid Gmez Jaime García-Mena Sofía Díaz-Cintra Gustavo Pacheco-Lpez 《International journal of molecular sciences》2022,23(15)
Alzheimer’s disease (AD) is a multifactorial pathology characterized by β-amyloid (Aβ) deposits, Tau hyperphosphorylation, neuroinflammatory response, and cognitive deficit. Changes in the bacterial gut microbiota (BGM) have been reported as a possible etiological factor of AD. We assessed in offspring (F1) 3xTg, the effect of BGM dysbiosisdysbiosis in mothers (F0) at gestation and F1 from lactation up to the age of 5 months on Aβ and Tau levels in the hippocampus, as well as on spatial memory at the early symptomatic stage of AD. We found that BGM dysbiosisdysbiosis with antibiotics (Abx) treatment in F0 was vertically transferred to their F1 3xTg mice, as observed on postnatal day (PD) 30 and 150. On PD150, we observed a delay in spatial memory impairment and Aβ deposits, but not in Tau and pTau protein in the hippocampus at the early symptomatic stage of AD. These effects are correlated with relative abundance of bacteria and alpha diversity, and are specific to bacterial consortia. Our results suggest that this specific BGM could reduce neuroinflammatory responses related to cerebral amyloidosis and cognitive deficit and activate metabolic pathways associated with the biosynthesis of triggering or protective molecules for AD. 相似文献