Summary
To provide reliable data storage and retrieval services to the end users, the cloud service provider implements secure data storage, sharing, and retrieval mechanisms. However, the aforesaid ...services provided by cloud have certain pitfalls, such as decision latency and real‐time data computation. To address these aforementioned problems, fog computing was introduced for the purpose of providing cloud services at the network's edge. While this migration of the cloud services to the network's edge raises various security concerns, such as trust, authentication, mobility, intrusion, network security, and secure data computation. Among these concerns, the most critical issues that need immediate attention of researchers and practitioners are of privacy and access control in fog computing which are in direct relation to secure data storage and retrieval purposes. So, in order to highlight their importance for research community, this survey embodies to discuss, explain, and compare various privacy preserving and access control schemes in the context of fog computing for classifying and analyzing similarities and variances with respect to other researchers. Moreover, upon classification and analysis of these schemes, various open issues and future directions are also presented for researchers and practitioners for the purpose of enhancing security algorithms to address privacy and access control issues in fog computing.
This paper has surveyed state‐of‐the‐art privacy and access control schemes for fog computing.
It has proposed a thematic taxonomy to classify the literature based on set of parameters.
It has put forward numerous key research problems in this field of research to strengthen privacy and access control schemes.
Retrieval constitutes a highly regulated and dynamic phase in memory processing. Its rapid temporal scales require a coordinated molecular chain of events at the synaptic level that support transient ...memory trace reactivation. AMPA receptors (AMPAR) drive the majority of excitatory transmission in the brain and its dynamic features match the singular fast timescales of memory retrieval. Here we provide a review on AMPAR contribution to memory retrieval regarding its dynamic movements along the synaptic compartments, its changes in receptor number and subunit composition that take place in activity dependent processes associated with retrieval. We highlight on the differential regulations exerted by AMPAR subunits in plasticity processes and its impact on memory recall.
Several suggestions for a class of theories of recognition memory have been proposed during the past decade. These models address predictions about judgments of prior occurrence of an event, not the ...identification of what it is. The history and current status of one of these models is discussed. The model postulates the detection of familiarity and the utilization of retrieval mechanisms as additive and separate processes. The phenomenal experience of familiarity is assigned to intraevent organizational integrative processes; retrieval depends on interevent elaborative processes. Other current theoretical options are described, and relevant supportive data from the literature are reviewed. New tests of the model involving both free recall and word pair paradigms are presented. The dual process model is extended to the word frequency effect and to the recognition difficulties of amnesic patients. (68 ref)
Frontal Lobe Damage and Memory Millichap, J Gordon
Pediatric neurology briefs,
06/1998, Volume:
12, Issue:
6
Journal Article
Peer reviewed
Open access
Skin conductance responses (SCRs) were recorded in a patient with frontal lobe damage and in normal control subjects while attempting recognition of famous and unfamiliar faces.
Computers provide exciting possibilities for enhancing children's dietary recording. Class discussions were conducted with 20 third- through fifth-grade classes (n = 337 students) to identify ...preferred computer game formats, assess student ability to quantify and record portion sizes, and collect information on recall of eating habits. Receiving immediate gratification (e.g., challenging, fun) was the most frequent reason for playing computer games. Quantifying food amounts was difficult. Most students preferred selecting “mounds” (not measuring cups) to record amount eaten. Although most students could identify type of milk consumed, they were less sure of margarine/butter or mayonnaise type.
Though soil is widely known as one of the most valuable resources for the world, its quality is going to be lower because of unsustainable economic development and social progress. Therefore, it is ...important for us to monitor and evaluate the quality of soil, especially its heavy metal contents which is too scarce to identify in soil spectra easily but poisonous enough to affect human health in a long run. Most of the existing estimation methods have based the characteristic bands on statistical analysis to a large extent, which is hard to accurately explain the retrieval mechanism. In this paper, the absorption characteristics of heavy metal are studied based on the soil spectra, and the distribution pattern is mapped in a large-scale continuous space, for environmental monitoring and further decision support. Taking Yitong County, China as the study area. After spectra continuum removal, the heavy metal contents were estimated by 11 features including the absorption depth, absorption area, and band ratio around 2200 nm, which showed the best performance. For arsenic (As), the best model yields Rp2 value of 0.8474, and the RMSEP value is 36.1542 (mg/kg). It is concluded that As is adsorbed by organic matter, clay minerals, and iron/manganese oxides in soil, and the adsorption of As by first two components is greater than that of the last. For airborne spectra after continuum removal, combining the spectral absorption characteristic parameters and the highly correlated bands is more accurate than using the spectral absorption characteristic parameters or bands alone. AdaBoost is presented for the heavy metal estimation, and the fitting ability of the method is found to be stronger than that of the traditional classical methods, with the Rp2 values of 0.6242 and the RMSEP value of 43.6481 (mg/kg). In summary, these results will provide a prospective basis for the rapid estimation of soil heavy metals, the risk assessment of soil heavy metals and soil environmental monitoring in a large scale.
•Potential of airborne hyperspectral image for heavy metal estimation was explored.•The spectral absorption characteristics can be used to build the As estimation model.•AdaBoost outperformed other methods for As estimation in a large-scale.
It is generally believed that an osmotically generated pressure gradient drives the phloem mass flow. So far, this widely accepted Münch theory has required remarkably few adaptations, but the debate ...on alternative and additional hypotheses is still ongoing. Recently, a possible shortcoming of the Münch theory has been pointed out, suggesting that the Münch pressure flow is more suitable for herbs than for trees. Estimation of the phloem resistance indicates that a point might be reached in long sieve tubes where the pressure required to drive the Münch flow cannot be generated. Therefore, the relay hypothesis regained belief as it implies that the sieve tubes are shorter then the plant’s axial axis. In the source phloem, three different loading strategies exist which probably result from evolutionary advantages. Passive diffusion seems to be the most primitive one, whereas active loading strategies substantially increase the growth potential. Along the transport phloem, a leakage-retrieval mechanism is observed. Appreciable amounts of carbohydrates are lost from the sieve tubes to feed the lateral sinks, while a part of these lost carbohydrates is subsequently reloaded into the sieve tubes. This mechanism is probably involved to buffer short-term irregularities in phloem turgor and gradient. In the long term, the mechanism controls the replenishment and remobilization of lateral stem storage tissues. As phloem of higher plants has multiple functions in plant development, reproduction, signalling, and growth, the fundamental understanding of the mechanisms behind phloem transport should be elucidated to increase our ability to influence plant growth and development.
The retrieval mechanisms associated with the recall of autobiographical memories (AMs) may differ according to the cueing method used to elicit AMs. In the present study, we provide a systematic ...comparison between word-cued and important AMs in terms of two recall order effects, namely a temporal and an emotional order effect. The sample comprised 104 adults aged between 59 and 90 years. On two measurement occasions, participants recalled up to 20 word-cued and 15 important AMs. For each memory, participants provided their age at the time when the event occurred (age-at-event) and rated its emotionality. Order effects were analysed based on multivariate multilevel model with autoregressive effects for emotionality and age-at-event, respectively. Whereas word-cued AMs showed a stronger emotional order effect, important AMs were recalled temporarily ordered. Individuals differed in the extent to which they ordered AMs along a temporal or emotional dimension. These differences could partly be explained by personality traits. For instance, higher scores on neuroticism were associated with a stronger emotional order effect in both memory types. Findings are discussed in terms of the retrieval mechanisms that are involved in the recall of word-cued and important memory recall and how they may be affected by personality.
Human motion retrieval from motion capture data forms the fundamental basis for computer animation. In this paper, the authors propose an efficient human motion retrieval approach via temporal ...adjacent bag of words (TA-BoW) and discriminative neighborhood preserving dictionary learning (DNP-DL). The retrieval process includes two phases: offline training and online retrieval. In the first phase, the original skeleton model is first simplified and then pairwise joint distances are computed to characterize each motion frame. Then, a novel motion descriptor, namely TABoW, is proposed to discriminatively code the motion appearances, through which the articulated complexity and spatiotemporal dimensionality can be greatly reduced. Subsequently, by considering the neighborhood relationships of intraclass structure and the advantage of Fisher criterion, a DNP-DL method is exploited through which each human action can be discriminatively and sparsely represented by a linear combination of such dictionary atoms. In the second phase, a hierarchical retrieval mechanism is used by incorporating the sparse classification and chi-square ranking, whereby the searching range is significantly reduced. The experimental results show that the proposed human motion retrieval approach performs better than the state-of-the-art competing approaches.
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