Co–Ti- and Mn–Ti-substituted barium ferrite for electromagnetic property tuning and enhanced microwave absorption synthesized via mechanical alloying

Substituted barium hexaferrite nanoparticles with nominal composition of BaCo1.0Ti1.0Fe10O19 and BaMn0.8Ti0.8Fe10.4O19 were synthesized by high energy ball milling (HEBM). The effects of Co–Ti and Mn–Ti substitution on their microstructure, electromagnetic properties, and microwave absorptive behavior were analyzed. The samples were structurally characterized by X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray analysis (EDX). The M-H loops of the composites were determined with a vibrating sample magnetometer (VSM), and the interaction with the microwave radiation in the range of 8–18 GHz of the nanocomposites dispersed in epoxy resin was measured with a vector network analyzer (VNA). This study suggests that by controlling the grain size and different elements of substitution would give a decrease in coercivity and enhanced values of complex permittivity in order to improve microwave absorption. The dielectric constant and loss were enhanced in comparison to the permeability constant and loss over the entire frequency range. Finally, microwave measurement showed that the substituted barium hexaferrite sample with Co–Ti and Mn–Ti could be used as an efficient microwave absorption material with an appropriate absorption at −31.27 and −26.73 dB, respectively. The predicted absorption and reflection loss demonstrates that Co–Ti and Mn–Ti substitution gives low reflectivity at microwave frequency and is a good candidate for electromagnetic materials for radar wave applications

An Application of Cuckoo Search Algorithm for Solving Combined Economic and Emission Dispatch Problem

This paper presents the application of Cuckoo Search Algorithm (CSA) in solving the combined economic and emission (CEED) dispatch problem. As been known, CEED can be formulated as a multi-objective optimization problem which is involving two objectives that conflicting each other. The objective is to find the tradeoff between minimizing the costs of fuel as well as minimizing the emission levels simultaneously while satisfying all the constraints. In this paper, this bi-objective function is transformed into a single objective function by introducing the price penalty and weighting factors. In order to show the effectiveness of CSA in solving CEED, two test systems are used: 6-units and 40-units generator systems. The comparison with other recent techniques is also given in this paper

The Property in Islam (Imam Muhammad Abu Zahrah\u27s Perspective)

Based on an observation through many communities, it is obviously that people are very careless on the possession of property, or even merely to get the advantage from it. They used not to think about, but prefer to neglect, the rightness of owning, the rightness of acquiring and the rightness of spending the property. In their mind is whatever they can gain, irrespective to the ethic and moral on the way of reaching and gaining, is totally belong to them, and they are free to do so ever. It is a very liberal concept of property.As a way of life, Islamic order ruled all aspects of life including the ownership of the property. There many verses of Al Qur\u27an as well as the teaching of the prophet Muhammad PBUH about the property. But the problem is there are many muslim scholars who has interpreted Al Qur\u27an on the fact and reality based only, and not due to the core of the mission of Al Qur\u27an. Not to pick the Qur\u27an teaching up to the life, or to build up the life depend on the doctrine of Qur\u27an, as it is ought to.Imam Muhammad Abu Zahrah, the famous and prominent Egyptian muslim scholar in the first twentieth century who has great intention and desire of the implementation of Islamic law was one who has keen interest on the issue of economy, especially on the issue of usury (riba). He has written several articles, papers and a book as well, on the subject of riba. Moreover, he has also written a set of Qur\u27anic Interpretation (Tafsiir) in which he commented on some verses concerning the property and wealth

Influence of the transom immersion to ship resistance components at low and medium speeds

The transom stern offered some advantages over the traditional rounded cruiser stern reducing the resistance of a ship. This can only be achieved if the transom stern is carefully designed with suitable transom immersion ratio. In this study, the influence of different transom area immersion ratios on the resistance components was investigated for a semidisplacement hull and a full displacement hull. The base hull was based on NPL hull form and KCS hull form for a semi-displacement and full-displacement hull respectively. The transom immersion ratios for the NPL hull were varied at a ratio of 0.5, 0.7, 0.8 and 1.0. The resistance of each of the NPL hull form was simulated at Froude number 0.3 up to 0.6. The transom immersion ratios for the KCS hull were varied at a ratio of 0.05, 0.1, 0.15 and 0.3. The resistance of each of the KCS hull form was simulated at Froude number 0.195, 0.23, 0.26 and 0.28. The transoms of both hulls were modified or varied systematically to study the influence of the transom shape or immersion on the total and wave resistance components. The investigation was carried out using a CFD software named SHIPFLOW 6.3 based on RANSE solver. These results on the NPL hull shows that the larger the transom immersion, the higher the resistance will be for a semi-displacement vessel. The increased resistance is contributed by additional frictional and wave resistance components. The results for the KCS hull seems to contradict with the results obtained from the NPL hull. The larger and deeper transom for the case of KCS hull form sometimes can be beneficial at higher Froude number

Occupational Safety and Health in Construction Industry Management (OSHCIM) implementation - academician's perspectives

The high incidents number of injuries and fatality rates in the construction industry are generally due to hazards on site. Early intervention of hazards could lead to safer construction processes. The Safety by Design (SbD) is a process that identifies hazard and assesses risks early in the project design stage, in comparison to during the construction stage. A study in Spain shows that there is still lack of emphasis on the SbD concept in higher education although the concept had been implemented for quite some time. The lack of tertiary education regarding SbD could lead to insufficient knowledge for the effective implementation of SbD by future professionals. As for the Malaysian construction industry, SbD will be soon implemented as the Guidelines on Occupational Safety and Health in Construction Industry (Management) - OSHCIM. Therefore, this paper sought to review the perception of academician regarding OSHCIM implementation. The quantitative strategy is adopted, and a set of questionnaires are distributed among academicians involved in educating architecture, civil engineering, quantity surveying, mechanical and electrical engineering courses in Malaysia's Institute of Higher Learning. The research indicates that most of the academicians appear to agree that sufficient knowledge and the right attitude is essential for the successful implementation of SbD education in university. It seems that all academicians from different background have higher attitude mean score compared to their knowledge mean score. Even though some of the academicians might not be familiar with the concept, most of the academician was not against it and had a positive attitude towards it

Risk assessment of design components of building construction

Lack of designer's knowledge of construction safety risks and HSE personnel's knowledge of structural designs and means and methods of construction have been highlighted as significant barriers to the implementation of design for construction safety. These barriers often result in poor collaboration among designers and HSE personnel in addressing safety issues that lead to accidents and frequent work stoppages. This study explored the ability of HSE officers, engineers and superintendents to recognize and assess risk associated with constructing structural components of a building (foundation, columns, walls, beams and roofs). The objective was to determine how consensus is risk perceived among the three groups of field personnel. The paper used a quantitative methodology that evaluates safety risks related to performing construction activities to supports designers to carry out construction designs using a risk assessment-based approach. The methodology compares cumulative risks of five designs and ranks the severity level of each design. The methodology also compares risk perception among HSE personnel, engineers and superintendent. Using this method of risk assessment will identify significant risks during design stage and highlight them in advance. Thus, a range of risk elimination or mitigation measures will be implemented before and during construction. The study was done with a survey questionnaire, and 40 construction field personnel (12 HSE, 14 superintendents and 12 engineers) were asked to evaluate risk's level of severity and time of exposure for each activity. Data collected were analysed with SPSS Statistics using descriptive statistics, general linear models (Multivariate) and Bivariate correlations (Pearson and Spearman). The results of the analysis showed that roof construction was perceived to have the highest risk followed by beam, foundation, wall and column. The differences in risk perceptions among the respondents were found to be non-significant statistically