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This paper aims to propose a boundary element analysis of two-dimensional linear elasticity problems by a new expanding element interpolation method.

The expanding element is made up based on a traditional discontinuous element by adding virtual nodes along the perimeter of the element. The internal nodes of the original discontinuous element are referred to as source nodes and its shape function as raw shape function. The shape functions of the expanding element constructed on both source nodes and virtual nodes are referred as fine shape functions. Boundary variables are interpolated by the fine shape functions, while the boundary integral equations are collocated on source nodes.

The expanding element inherits the advantages of both the continuous and discontinuous elements while overcomes their disadvantages. The polynomial order of fine shape functions of the expanding elements increases by two compared with their corresponding raw shape functions, while the expanding elements still keep independence to each other as the original discontinuous elements. This feature makes the expanding elements able to naturally and accurately interpolate both continuous and discontinuous fields.

Numerical examples are presented to verify the proposed method. Results have demonstrated that the accuracy, efficiency and convergence rate of the expanding element method.

Molecular dynamics is an emerging simulation technique in the field of machining in recent years. Many researchers have tried to simulate different processing methods of various materials with the theory of molecular dynamics (MD), and some preliminary conclusions have been obtained. However, the application of MD simulation is more limited compared with traditional finite element model (FEM) simulation technique due to the complex modeling approach and long computation time. Therefore, more studies on the MD simulations are required to provide a reliable theoretical basis for the nanoscale interpretation of grinding process. This study investigates the crystal structures, dislocations, force, temperature and subsurface damage (SSD) in the grinding of iron-nickel alloy using MD analysis.

In this study the simulation model is established on the basis of the workpiece and single cubic boron nitride (CBN) grit with embedded atom method and Morse potentials describing the forces and energies between different atoms. The effects of grinding parameters on the material microstructure are studied based on the simulation results.

When CBN grit goes through one of the grains, the arrangement of atoms within the grain will be disordered, but other grains will not be easily deformed due to the protection of the grain boundaries. Higher grinding speed and larger cutting depth can cause greater impact of grit on the atoms, and more body-centered cubic (BCC) structures will be destroyed. The dislocations will appear in grain boundaries due to the rearrangement of atoms in grinding. The increase of grinding speed results in the more transformation from BCC to amorphous structures.

This study is aimed to study the grinding of Fe-Ni alloy (maraging steel) with single grit through MD simulation method, and to reveal the microstructure evolution within the affected range of SSD layer in the workpiece. The simulation model of polycrystalline structure of Fe-Ni maraging steel and grinding process of single CBN grit is constructed based on the Voronoi algorithm. The atomic accumulation, transformation of crystal structures, evolution of dislocations as well as the generation of SSD are discussed according to the simulation results.

The purpose of this study is to develop a Turing machine or a finite automaton, which scans the input data tape in the form of DNA sequences and inspires the basic design of a DNA computer.

This model based on a splicing system can solve fuzzy reasoning autonomously by using DNA sequences and human assisted protocols. Its hardware consists of class IIS restriction enzyme and T4 DNA ligase while the software consists of double stranded DNA sequences and transition molecules which are capable of encoding fuzzy rules. Upon mixing solutions containing these components, the automaton undergoes a cascade of cleaving and splicing cycles to produce the computational result in form of double stranded DNA sequence representing automaton's final state.

In this work, the authors have fused the idea of a splicing system with the automata theory to develop fuzzy molecular automaton in which 1,018 processors can work in parallel, requiring a trillion times less space for information storage, is 105 times faster than the existing super computer and 1,019 power operations can be performed using one Joule of energy.

This paper presents a generalized model for biologically inspired computation in nano scale.

To present the mechanism, on which the first module was successfully designed – the automated installation application system, in the grand automated management and evaluation for community health service (CHS) sector of China.

The automated installation application system is constructed on the platform of Visual FoxPro8.0. The construction consists of five steps. The first is to establish the “item.” The function of “the item” is to trace all procedures, forms, menus, and various databases, such as tabulated data, summary data, and other types of data. The second is to establish the customer log‐in module. This module needs to contain a roll book of authorized customers. The third is to construct the subsystem management interface. This interface includes: entering installation the application, modifying and saving and transferring out the information, searching, printing blank form and statement. The fourth is to establish a roll book of all forms and the database of all the forms. The fifth is to establish the main procedure, connecting all the modules in the working order.

The main advantage of the system is that it is helpful for the characteristics of speedy information importation, clear and straight to the point, as well as the secure and accurate data transfer.

Automated management and evaluation for CHS heavily depends on the initial activation and this initiation is started using the system of installation application.

The purpose of this paper is to employ lessons learned from the industrial accidents in Skikda refinery during the period from 2005 to 2016 as input data for the numerical simulation of risk consequences to identify the exposed areas to the various effects of industrial accidents.

In order to assess how the lessons learned can contribute to modeling the accidents effects in the refining activities, this paper presents a combined statistical/dynamic approach that combines two main tools, namely, lessons learned from petroleum refining in Algeria and Areal Locations of Hazardous Atmospheres software.

The results showed that fire is the most frequent accident at Skikda refinery that is mainly caused by equipment failures with a frequent involvement of crude oil and LNG. The NO₂ toxic effects are unacceptable. This means that in the case of a similar accident, the entire population will be exposed to an intolerable concentration of NO₂. Therefore, people must be relocated to a safer place. The results indicate that the concentration threshold can be met beyond the distance of 1 km.

Due to the economic importance of Skikda refinery and the absence of data related to the accidents in the refineries of Algiers, Arzew and Hassi Messaoud, this study is limited to the statistical analysis of accidents related to Skikda refinery.

This approach makes the risk assessment more practical and effective for the appropriate utilization of safety barriers and for the whole decision-making process.

This work presents a review paper of accidents that occurred in the oil-refining sector in Algeria, whose objective is learning lessons from past accidents history, by identifying their immediate causes and effects on personnel, equipment and environment in order to propose prevention measures. The novelty of this work is highlighted by the fact that this statistical analysis of oil and gas refining accident is realized for the first time in Algeria. This is due to the difficulty of obtaining data on accidents in the Algerian refining sector; for this reason, the authors have limited the study to the Skikda refinery.