Advanced Materials Research Vols. 383-390

Abstract: In this article service-oriented architecture is implemented in crisis environments (such as in a place on fire). Our purpose is to use wireless sensor networks and multi-agent systems in crisis environments to gather information from the environment. This information is received by sensor nodes, it is then processed in the expert system, the deductions concerning the environment from which information has been gather are sent to the central controller, and then the central controller sends the messages to the human agent who becomes aware of the situation in the environment in order to carry out the prescribed duties.

Abstract: In this paper, based on the modified slab method theory, an analytical solution for ring rolling process is presented. The non-uniformity of the normal and shear stresses across the section of the deforming material are considered. The friction factor multiplied by the shear yield strength is used to present friction between the main roll and the ring. Complete expressions for the ring rolling pressure, force and torque are obtained and the position of neutral point is predicted. The influence of the process parameters such as friction factor, main roll rotational speed, feed speed, and others was investigated. Analytical results obtained from the present formulation were compared to previous experimental works and good agreement and improvements were observed.

Abstract: This study seeks a model for Knowledge Management in project based firms. The work process in these firms is getting on a contract with a client over a project which is to be delivered in a certain period of time and with a certain amount of budget. Depending on the type and specification of the project, the firm achieves or creates some knowledge which is almost tacit. The concern here is that this tacit knowledge is lost by the end of the project, whether due to time limitations and rush for delivering the project which makes it impossible for the firm to turn this knowledge into explicit; or it goes away with the workers since they are generally project-loyal not company-loyal. Based on the literature this study reveals that KM can act as powerful instrument for increasing project-based firms’ performance and hence raise their chances for absorbing more projects. However this is a two-sided fact; clients have more faith in those firms with loaded with high-level experiences while the chances are higher for satisfying clients in those firms which manage their knowledge gained from earlier projects.

Abstract: With the compact nature and the high electrical-connection density, flexible printed circuits (FPC) can achieve considerable weight, space and cost savings over the use of traditional rigid printed circuit boards. In recent years, it becomes impossible without flexible printed circuit technology in electronic products especially for Flip mobile phones. Whereas, its application is not always satisfied the engineering of assembly and reliability due to the existing of mechanical stress in soldering process and service environment. In this paper, through analyzing the common failures in mass production including via interconnection, trace crack and black pad, some preventions were suggested to improve the quality and reliability at the aspect of manufacture, process, mechanical design and dynamic stress distribution philosophy.

Abstract: Since the use of computers in business world, data collection has become one of the most important issues due to the available knowledge in the data; such data has been stored in database. Database system was developed which led to the evolvement of hierarchical and relational database followed by Standard Query Language (SQL). As data size increases, the need for more control and information retrieval increase. These increases lead to the development of data mining systems and data warehouses. This paper focuses on the use of data warehouse as a supporting tool in decision making. We to study the effectiveness of data warehouse techniques in the sense of time and flexibility in our case study (Manpower Employment). The study will conclude with a comparison of traditional relational database and the use of data warehouse. The fundamental role of data warehouse is to provide data for supporting decision-making process. Data in data warehouse environment is multidimensional data store. We can simply say that data warehouse is a process not a product, for assembling and managing data from various sources for the purpose of gaining a single detailed view of part or all an establishment. The data warehouse concept has changed the nature of decision support system, by adding new benefits for improving and expanding the scope, accuracy, and accessibility of data. The warehouse is the link between the application and raw data, which is scattered in separate database but now is unified. The objectives of this work are to study the impact of using data warehouse on Manpower Employment Decision Support System, in the sense as far as the data quality concern. We will focus on the benefits gained from using data warehouse, and why it is more powerful than the use of traditional databases in decision making. The case study will be the Libyan national manpower employment agency. The data warehouse will collect database scattered from different sources in Libya in order to compare the performance and time.

Abstract: In this article, it is tried to study the role of IT powerful tools to change in identity of procedure in developmental project management from traditional space to virtual space (conversion of project traditional management to project electronic project) and also it is studied how to enforce electronic methods in managing projects and it’s effect on expense/time and quality factors with modeling a developmental project as a pilot project to exiting systems and procedures in projects. Since in accordance to PMBOK [6] viewpoint, project management process can be defined as management on multiple domains such as Communication, Provisions, Cost, Quality and time. Therefore, in this article, some suggestive algorithms will be introduced to show the feasibility of virtual making and web-based management of one of the domains of project management. (Cost domain)

Abstract: Gas Tungsten Arc Welding (GTAW) is one of the most widely used welding process in industry. The input parameters play a very significant role in determining the quality of a welded joint (geometry of weld bead). The joint quality can be evaluated by studying the features of weld bead geometry (output parameters) such as Bead Width (BW), Bead Height (BH) and Depth of Penetration (DP). Present study focused on welding of austenitic stainless steel sheets using GTAW process with 316L material. The output variables are determined according to gas flow rate, travel speed and current. Grey relational analysis is applied to optimize the input parameters simultaneously considering the multiple output variables. Finally, confirmation experiment has been conducted to validate the optimized parameters and found to be correlated.

Abstract: Welding is one of the major processes used in the manufacturing industry. The base materials, welding consumable materials and physical and chemical phenomena, which are connected with high temperature and UV radiation, are emission source of welding fumes. The particulate solid dust and various gases are included in welding fumes. This paper addresses the experimental investigation made to study the process parameters on formation and composition of fumes during shielded Metal Arc welding (SMAW) of stainless steel. The process variables include electrode diameter and welding current. It was observed that, the welding current and electrode diameter have a positive effect on the fume formation that is, increase in welding current and electrode diameter caused an increase in the concentration. All the metallic constituents attached to it also exhibited the same behavior.

Abstract: In the present work hot corrosion studies were carried out on electron beam welded AISI 304 and AISI 4140 dissimilar weldment in molten salt (K₂SO₄-60% NaCl) environment at 800 °C for 50 cycles. The weight gain follows parabolic law in all the cases. It is observed that the scale formation was maximum on 4140 side as compared on 304 side. Moreover higher content of Fe₂O₃ and Cr₂O₃ on scale over weld zone may be due to enrichment of this zone with Fe and Cr. This could be attributed to diffusion of chromium towards AISI 4140 from the AISI 304 and diffusion of iron from AISI 4140 side towards AISI 304. Furthermore weld interface suffered accelerated corrosion behavior in the chloride and sulfate mixed molten salt environment in the form of intense spalling and sputtering of its scale. The cracking of oxide scale on the weldment might be attributed to different composition of base metals, weld metal and oxide formed.

Abstract: This study aims to investigate the influence of intermetallics morphological modification on mechanical properties of iron-containing Al-Si-Mg casting alloys. The modification of the intermetallics was performed by using melt-shearing treatment prior to commercial high pressure die casting. The process parameters of the melt-shearing treatment were controlled and optimized based on the theoretical consideration of the intermetallics formation behavior. It was found that the mechanical properties of low-iron containing Al-Si-Mg alloy was improved due to the modification of primary α-Al from dendritic to globular form by the melt-shearing. Regarding to high-iron containing Al-Si-Mg alloy, harmful morphology of intermetallics was successfully modified by the melt-shearing at semi-solid region, which results in the improvement of mechanical properties such as elongation.