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Carbon nanotube field effect transistor (CNFET) is one of the promising technologies as a replacement for current CMOS technology due to its excellent electronic properties. CNFETs can be fabricated in regular structures, making them ideal for creating the repetitive architectures found in field programmable gate arrays (FPGAs). However, CNFETs face some fabrication challenges. The unwanted metallic carbon nanotubes (CNTs) are one of the major challenges in using CNFET technology for FPGAs. In this paper, we take the advantage of FPGAs programmability allowing reconfiguration around the metallic CNTs to tolerate this defect. We demonstrate a multi-stage solution to the metallic CNT problem in CNFET-based FPGAs that does not require any metallic nanotube removal of any kind. The proposed methodology consists of four consecutive stages in logic mapping process: (i) reordering of input variables, (ii) inputs complementing, (iii) adding inputs redundancy to basic logic element (BLE) and (iv) BLE lookup table (LUT) splitting. A fault simulation tool is designed to work closely with VPR, an academic FPGA CAD tool, to provide the investigation of metallic CNTs effects on CNFET-based FPGAs. Experimental results show that the proposed method can successfully map all logical nets at a cost of $4.5\times$ area overhead if the fraction of metallic CNTs is reduced to 30%.

Providing dynamic resources is based on the virtualization features of the cloud environment. Cloud computing as an emerging technology uses a high availability of services at any time, in any place and independent of the hardware. However, fault tolerance is one of the main problems and challenges in cloud computing. This subject has an important effect on cloud computing, but, as far as we know, there is not a comprehensive and systematic study in this field. Accordingly, in this paper, the existing methods and mechanisms are discussed in different groups, such as proactive and reactive, types of fault detection, etc. Various fault tolerance techniques are provided and discussed. The advantages and disadvantages of these techniques are shown on the basis of the technology that they have used. Generally, the contributions of this research provide a summary of the available challenges associated with fault tolerance, a description of several important fault tolerance methods in the cloud computing and the key regions for the betterment of fault tolerance techniques in the future works. The advantages and disadvantages of the selected articles in each category are also highlighted and their significant challenges are discussed to provide the research lines for further studies.

Most complex systems today contain software, and systems failures activated by software faults can provide lessons for software development practices and software quality assurance. This paper presents an analysis of software-related failures of medical devices that caused no death or injury but led to recalls by the manufacturers. The analysis categorizes the failures by their symptoms and faults, and discusses methods of preventing and detecting faults in each category. The nature of the faults provides lessons about the value of generally accepted quality practices for prevention and detection methods applied prior to system release. It also provides some insight into the need for formal requirements specification and for improved testing of complex hardware-software systems.

It took centuries for scientists to come to the plate tectonic theory, so as our generation understands that a tectonic earthquake is generated by the fault movement. However, it is not always easy to discover an active fault before its rupture during a large earthquake in our life-span, for it is buried underneath the recent sediment. A single 3-component seismometer proposes a simple way yet robust to expose subsurface geological structures. A single station HVSR method alone has successfully unearthed the buried faults zone of Palu Koro which is crossing Palu City. The buried faults lie beneath the soil of Greater Jakarta, the largest economic growth area, such as Cisadane, Kali Bekasi, and as well Baribis that crossing Semarang City. were convincingly portrayed. Although their activity rate could not be carried out by using this method, the research area for an advanced technique was localized. Having shear-wave velocity profile enabling us to map thickness of soft sediment in Semarang city. It allows us to delineate subsidence potential area, are having sediment thickness 8 m or more increases the subsidence potential in this city.

According to the characteristics of acoustic fault sources of underwater vehicles, a novel sources detection model using radial basis function (RBF) neural network based on fuzzy clustering algorithm is proposed. The extended fuzzy c-means (FCM) clustering algorithm is utilized to determine the number of hidden neurons, especially, the output layer neurons can be modified on-line so that the network has the capability of incremental learning. An example of diagnosis indicates that the proposed neural network diagnosis system can detect and recognize new faults, and can learn incrementally.

Twin substructures of Fe-Mn TWIP steel at different annealing temperatures and after tensile deformation were examined by transmission electron microscope. The results show that when annealing temperature is at 780°C, fault and twin coexist in austenite microstructure. When annealing temperature is at 820~850°C, a large number of annealing twin substructures in the austenite colony are formed and the twin lamella thickness ranges from 50nm to 150nm. During tensile deformation process, a large amount of deformation twins are generated, TWIP effect happens, twin substructure density increases, and the twin spacing and slice thickness of about 50nm decreases.