No abstract

In order to identify the strategic topics and the thematic evolution structure of data mining applied to healthcare, in this paper, a bibliometric performance and network analysis (BPNA) was conducted. For this purpose, 6138 articles were sourced from the Web of Science covering the period from 1995 to July 2020 and the SciMAT software was used. Our results present a strategic diagram composed of 19 themes, of which the 8 motor themes (‘NEURAL-NETWORKS’, ‘CANCER’, ‘ELETRONIC-HEALTH-RECORDS’, ‘DIABETES-MELLITUS’, ‘ALZHEIMER’S-DISEASE’, ‘BREAST-CANCER’, ‘DEPRESSION’, and ‘RANDOM-FOREST’) are depicted in a thematic network. An in-depth analysis was carried out in order to find hidden patterns and to provide a general perspective of the field. The thematic network structure is arranged thusly that its subjects are organized into two different areas, i) practices and techniques related to data mining in healthcare, and ii) health concepts and disease supported by data mining, embodying, respectively, the hotspots related to the data mining and medical scopes, hence demonstrating the field’s evolution over time. Such results make it possible to form the basis for future research and facilitate decision-making by researchers and practitioners, institutions, and governments interested in data mining in healthcare.

No abstract

No abstract

No abstract

No abstract

The network on chip (NoC) design process requires an adequate characterization of the application running on it to optimize communication resources utilization and dimensioning. The traffic modeling process is the most essential step for characterizing complex applications. It is possible to identify three methods to model traffic in NoC literature. The first one assumes sources continually send data at a constant rate to the network and it is the most commonly used. The second method employs probabilistic functions to model the traffic behavior for typical applications, as audio and video streams. The accuracy of this method is better, at the extra cost of modeling complexity and simulation time. The third method employs traffic traces to evaluate network performance. Even with small traces, simulation time can be prohibitive. The advantage is accuracy, superior to the previous models. Even if a given application is correctly modeled, other flows interfere on how the application traffic behaves within the network. Results about the mutual interference of different traffic flows in NoCs are scarce. This work has two main objectives: (i) compare NoC performance, in terms of throughput and latency, when different traffic models are used for the same application; (ii) evaluate the impact of network noise traffic on some specific modeled flow. Preliminary results show how far is the real NoC performance for a given application when an oversimplified model is employed. The conclusion is that NoCs must employ internal mechanisms to ensure QoS, since noise traffic makes modeled traffic to depart from its predicted behavior.

Networks on chip (NoCs) are communication infrastructures that offer parallelism and scalability. Most NoC designs employ wormhole packet switching, since this switching mode optimizes the use of NoC resources. However, this mode may introduce jitter, possibly producing packet loss, due to the violation of temporal QoS constraints. One technique to deal with jitter is to introduce a decoupling buffer (D-buffer) on the target IP. This buffer receives data from the NoC with jitter, while the target IP consumes data from this buffer at the application rate, without jitter. Two problems must be solved to implement D-buffers: (i) which size must the buffer have? (ii) how much buffer space should be filled before data consumption starts (threshold)? This work proposes a general method to define D-buffer size and threshold, considering the influence of packaging, arbitration, routing and concurrency between flows. Before presenting the method, the paper extends a previous traffic model for stream applications and characterizes jitter sources in wormhole packet switching. The experimental results obtained with the proposed method showed that simple traffic models employing constant frame sizes result in small D-buffers. On the other hand, employing video frames from application traces (i.e. real application data) increases buffer size and threshold, still suppressing jitter. Application traces highlight the threshold parameter importance.