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This paper presents the results of a heading estimation method for a remotely operated vehicle (ROV). The output rate of commercially available underwater compasses is typically in the order of a few Hz. Heading frequencies of at least 1 KHz are desirable for navigation and control purposes.

The estimation was performed by fusioning the signals of three inertial sensors: the ROV’s own underwater compass (which operates roughly at 10 Hz or less), the ROV’s embedded gyro and an additional angular rate sensor that provides readings from 1 to 3 KHz. The output signal of the additional angular rate sensor is not part of the proposed Kalman filter. Nonetheless a five-point Newton-Cotes closed integration of such signal is fed into the Kalman filter implementation that performs the required heading estimation at 1 KHz or more.

The proposed Kalman filter implementation is a suitable approach to estimate heading position even though the original compass signal rate is significantly slower than the signal required for both assisted and autonomous control.

The estimated heading yield good results in both simulation and experimental environments.

The method was embedded in a dedicated 16-bit DSP that handles both the acquisition of the three signals and the heading estimation, hence resulting in a very low-cost solution. The embedded solution was tested in the developed submarine and the obtained high-rate heading parameter is now used by the control system of the ROV.

This study aims to investigate the effects of nozzle momentum flux distribution on the flow field characteristics.

The nozzle configuration consists of a central nozzle surrounded by four nozzles. All nozzles have the same diameter and constant separation between nozzles. OpenFOAM® is used for simulating the jet flow. Reynolds-averaged Navier-Stokes (RANS) equations are solved iteratively with a first-order closure for turbulence. Pitot-static tube with differential pressure transducer is used for mean velocity measurements. The comparison of computed results with experimental data shows similar trend and acceptable validation.

According to the results, the momentum flux distribution significantly alters the near field of multiple turbulent round jets. Highly non-linear decay region in the near field is found for the cases having higher momentum in the outer jets. As a result of merging, increased positive pressure is found in the mixing region. Higher secondary flows and wider mixing region are reported as a result of momentum transfer from axial to lateral directions by Reynolds stresses.

The present study is limited to isothermal flow of air jet in air medium.

Optimum momentum flux distribution in multijet injector of a combustor can reap better mixing leading to better efficiency and lesser environmental pollution.

As summary, the contributions of this paper in the field of turbulent jets are following: simulations for various momentum distribution cases have been performed. In all the cases, the flow at the nozzle exit is subsonic along with constant velocity profile. To simulate proper flow field, a large cylinder-type domain with structured grid is used with refinements toward the nozzle exit and jet axis. The results show that the non-linearity increases with increase in momentum of outer jets. Longer merging zones are reported for cases with higher momentum in outer nozzles using area-averaged turbulent kinetic energy. Similarly, wider mixing regions are reported using secondary flow parameter and visualizations.

The purpose of this paper is to demonstrate, to construction professionals, the client benefits of archaeological building analysis.

The principles of the technique are summarised, followed by a summary of the academic and legal contexts in which such analyses are conducted. Three short case studies are presented, followed by methodological conclusions.

The paper finds that after c100 years of methodological development, client interests are not represented in any technical or professional guidance; and that historic buildings are structurally and cosmetically more complex than received architectural histories would have one believe and that much decorative detail is likely to be of relatively recent installation, information that can be of benefit to clients wishing to modify listed and other historic buildings.

While the introductions and legal and academic summaries are international in scope, the case studies are limited to its own work. Nonetheless, the principles established are applicable to all forms of historic buildings and refurbishment projects.

The paper posits that a hitherto regulatory burden can be applied in the clients' interests with only a slight adjustment in approach to well established survey techniques.

While the survey techniques described are well established in archaeological circles, the client‐oriented approach advocated here is not. Construction professionals dealing with historic buildings will find the approach of immediate practical benefit.

In recent years, fire accidents in engineering structures have often been reported worldwide, leading to a severe risk to life and property safety. The present study is carried out to evaluate the performance of Ground Granulated Blast Furnace Slag (GGBS) and fly ash–blended laterized mortars at elevated temperatures.

This test program includes the replacement of natural river sand with lateritic fine aggregates (lateritic FA) in terms of 0, 50 and 100%. Also, the ordinary Portland cement (OPC) was replaced with fly ash and GGBS in terms of 10, 20, 30% and 20, 40 and 60%, respectively, for producing blended mortars.

This paper presents results related to the determination of residual compressive strengths of lateritic fine aggregates-based cement mortars with part replacement of cement by fly ash and GGBS exposed to elevated temperatures. The effect of elevated temperatures on the physical and mechanical properties was evaluated with the help of microstructure studies and the quantification of hydration products.

A sustainable cement mortar was produced by replacing natural river sand with lateritic fine aggregates. The thermal strength deterioration features were assessed by exposing the control specimens and lateritic fine aggregates-based cement mortars to elevated temperatures. Changes in the mechanical properties were evaluated through a quantitative microstructure study using scanning electron microscopy (SEM) images. The phase change of hydration products after exposure to elevated temperatures was qualitatively analyzed by greyscale thresholding of SEM images using Image J software.

Today, most personal computers are equipped with floppy disk drives, but as needs for information storage on computers grow, ‘hard’ disks having larger capacities become more and more popular. The world population of hard disk units is increasing rapidly. About one and a half million of the 5¼″ size drives are expected to be shipped in 1984, and the pace for smaller, 3½″ units is expected to pass two million per year by 1986.

This paper aims to examine the effects of monetary policy and foreign shocks on output, inflation and exchange rate in Egypt.

This paper studies the effects of monetary policy and foreign shocks on output, inflation and exchange rate by using non-recursive SVAR model and quarterly data.

First, the empirical results reveal that monetary policy shocks, through changes in interest rate or money supply, have a significant effect on output, inflation and exchange rate in Egypt. Second, the world oil prices and foreign output have significant impacts on output, inflation and exchange rate in Egypt, while foreign interest rate has a significant effect on domestic output and inflation.

The limitation of the study is examining one country only.

The Central Bank of Egypt (CBE) should adjust interest rate to stabilize inflation, output and exchange rate. By stabilizing inflation, output and exchange rate, the CBE would be able to achieve the ultimate targets of monetary policy, namely, price stability and economic growth.

It is important for the CBE because it shows the significant effect of monetary policy on macroeconomic variables in Egypt. Also, it is important for people because it shows the important role for the CBE.

It is important for the CBE because it examines the effect of monetary policy and foreign shocks on macroeconomic variables.

This study aims to identify the predictors of successful implementations of pay equity plans. Drawing on the perspective of organizational justice, this study highlights the factors that lead to the establishment of perceived fair pay for female-dominated jobs.

Qualitative data were collected from 107 respondents in a Canadian company that implemented a pay equity plan as required by the Quebec Pay Equity Act.

Justice perceptions of employees are based on: uniformity of implementation, bias suppression with respect to the right to fair pay, reliability of information on job content, relevance of job evaluation criteria, qualifications and impartiality of the pay equity committee members and the quality of employees’ representation and process transparency.

This study was conducted at a single workplace and among relatively highly educated respondents. Replicating the study may allow to verify the transferability of the results by considering workers’ demographic characteristics and organizational culture.

The study highlights the cornerstones that may guide the development of an assessment tool of the effectiveness of pay equity processes. These results will additionally help employers to circumvent difficulties which may otherwise thwart the implementation of pay equity plans.

This study highlights how employees construct their perceptions of justice in a specific context. It sheds light on the salient features of the pay equity implementation, the sources of information involved and the justice rules used. This study also highlights the specific forms of the justice rules in this context.

Human–robot collaboration (HRC) is on the rise in a bid for improved flexibility in production cells. In the context of overlapping workspace between a human operator and an industrial robot, the major cause for concern rests on the safety of the former.

In light of recent advances and trends, this paper proposes to implement a monitoring system for the shared workspace HRC, which supplements the robot, to locate the human operator and to ensure that at all times a minimum safe distance is respected by the robot with respect to its human partner. The monitoring system consists of four neural networks, namely, an object detector, two neural networks responsible for assessing the detections and a simple, custom speech recognizer.

It was observed that with due consideration of the production cell, it is possible to create excellent data sets which result in promising performances of the neural networks. Each neural network can be further improved by using its mistakes as examples thrown back in the data set. Thus, the whole monitoring system can achieve a reliable performance.

Success of the proposed framework may lead to any industrial robot being suitable for use in HRC.

This paper proposes a system comprising neural networks in most part, and it looks at a digital representation of the workspace from a different angle. The exclusive use of neural networks is seen as an attempt to propose a system which can be relatively easily deployed in industrial settings as neural networks can be fine-tuned for adjustments.

Spirituality in the workplace is a concept that has been emphasized a lot in recent years. However, the relationship of this concept with gender and discrimination has not been adequately addressed. Individual and organizational positive outcomes of spirituality in the workplace cannot be obtained when discrimination is in question. This is because the concepts of spirituality and discrimination in the workplace are completely opposite to each other. In order to prevent discrimination based on gender, sexual orientation, race, age, religion, disability and to establish spirituality in the workplace, organizations should follow awareness and training programs to eliminate prejudices of their management and employees, give importance to differences, develop an understanding of democracy and justice within the organization and development egalitarian and anti-discrimination policies and application. In this direction, while the differences are managed correctly, spirituality will be established in the workplace.

Although in principle prior information can significantly improve inference, incorporating incorrect prior information will bias the estimates of any inferential analysis. This fact deters many scientists from incorporating prior information into their inferential analyses. In the natural sciences, where experiments are more regularly conducted, and can be combined with other relevant information, prior information is often used in inferential analysis, despite it being sometimes nontrivial to specify what that information is and how to quantify that information. In the social sciences, however, prior information is often hard to come by and very hard to justify or validate. We review a number of ways to construct such information. This information emerges naturally, either from fundamental properties and characteristics of the systems studied or from logical reasoning about the problems being analyzed. Borrowing from concepts and philosophical reasoning used in the natural sciences, and within an info-metrics framework, we discuss three different, yet complimentary, approaches for constructing prior information, with an application to the social sciences.