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The purpose of this study is to understand the functional power of frequency from-to chart (FFTC) as an independent solution-key for generation optimal (exact) facilities sequences with an equal distance of straight-line flow patterns. The paper will propose a bi-objective function model based on the Torque Method then will turn it into a computer-based technique with a permutative manner using the full enumeration method. This model aims to figure out if there is a difference between the moment minimization and backtracking treatment. Furthermore, the proposed technique will measure the performance of related works from literature to numerically highlight their limitations.

The literature of related works provided two-principles assumed mastering material flow sequences. The researchers gathered and analyzed the three methods – used FFTC as an independent technique – mentioned in the literature then measured their performance with the proposed technique. The proposed technique is based on the computation of torque value using an enhancement of bi-objective function model then application a permutative approach with full enumeration methodology. The bi-objective function model used once to mimic the grand moment value of FFTC and again to study the reflection of minimizing the congestion of backtracking movements on the minimization of total transportation cost.

Based on the analysis of literature and comparative results of its three case studies using the proposed technique, it is found that: there are optimum facilities sequences with rich opportunities of exact pathway selection. Reduction methodology is an inefficient way to generate exact results. There is a gap between combining the minimization of the grand moment and the treatment of the backtracking problem.

This study is one of the first contributions that discusses the assumption of integration between optimization moment value and its relation to treatment backtracking problem. Also, the illness of reduction methodology to reach optimal solutions. The further direction of this research will highlight the conjecture of searching the exact results for small size problems, analyzing the given data and its logical dimensions, developing logical rules for solving and verifying large size problems based on the exact results (The conjecture of P = NP).

This paper provides a detailed numerical analysis of the most common problems generally faced facility layout problems through understanding the lack of integration between moment minimization and backtracking minimization. Also, the inefficiency of reliance on reduction methodology either in scores of frequencies between facilities with weak relation or the number of permutations. Based on those findings, further study will search the logical philosophy exactly optimizing FFTC manually or without having to deal with a permutative approach for large size problems – which considered non-deterministic polynomial-time problem.

Claims are increasingly becoming a norm in construction projects and thus an area that is attracting interventions through researches. This paper aims to establish causes–effects relationship of claims in construction projects.

This is correlation study type of study that attempts to establish causes–effects relationship of claims in construction projects. Significant causes and effects of construction claims were determined using one-sample t-test. To establish the relationship, the significant causes and effects of construction claims were correlated using bivariate correlation analysis.

Among the significant causes, variations, change of scope of the project and delay in completion of works have high level of significant positive relationship with five to six other causes and positive relationship with multiple effects ranging from five to six. Besides, among significant effects, delay in completion and delivering of construction projects, poor contractual relationship among parties and extension of time have significant positive relationship with multiple causes.

The findings of this study are limited to causes-causes relationship and causes–effects relationship of claims in construction projects. This means effects–effects relationship was not covered that could be an important area to investigate as some of causes and effects are at times termed interchangeably.

With reference to previous studies which have focused on determining the causes and effects of construction claims, the findings of the current study have specific contribution on claims management as it divulges the causes of constructions claims that have multiplier effects to the project as a result of their linkage.

The paper unveils causes of claims with multiplier effects to construction projects for project participants to devise strategies to minimize and consequently eliminate them.

During the past few years, only a limited number of construction projects in Palestine were completed on time; indeed many of these projects had been delayed for reasons believed to be outside the control of both the contractors and owners. Such delays have given rise to many claims and conflicts. The aim of this paper is to investigate this widespread phenomenon, and its associated problems, from the perspective of the local contractors.

The paper reports on a questionnaire‐based research investigation targeting local contractors with a focus on critical problems associated with the process of claim management, starting with claim identification, through to claim notification, examination, documentation, presentation, and negotiation.

The paper presents the survey results and main findings which indicate that: lack of site staff awareness to proactively detect claims, inaccessibility or unavailability of relevant documents, and conflicts arising during owner/contractor negotiation are all critical problems associated with the process of claim management.

The outcome of this research will assist local contractors in understanding the critical problems associated with the process of claim management; thus minimizing the number of, and cost associated with, claims and conflicts.

Support at the organizational and managerial levels defines the degree to which construction workplaces can accommodate disabled and injured workers. There is little empirical evidence about the indicators and practices that can be used by construction organizations to evaluate disability management (DM). This paper aims to develop and validate key indicators and practices of disability/injury management within construction.

To achieve this, the research used a two-phase sequential exploratory review of literature, followed by a quantitative phase, using analytic hierarchy process. The analytical hierarchy process (AHP) involved recruiting eight health and safety and DM experts to conduct pairwise comparisons of these indicators.

The results found return-to-work and disability and injury management practices to be the most important indicators and physical accessibility and claims management practices to be the least important.

The development of these indicators should help construction organizations develop DM programs that better meet their needs, and benchmark and improve related performance.

The results could also be useful for all stakeholders in general and decision makers in particular involved within construction.

Such prioritization helps organizations to prioritize their DM practices thereby optimizing performance.

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound [N-(3-(dimethyl octyl ammonio) propyl) palmitamide bromide] (DMDPP), which is prepared through a simple and applicable method.

Weight loss was inspected at five different temperatures of 25°C, 30°C, 40°C, 50°C and 60°C Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation were used at room temperature. Density functional theory was used to study the relation between the molecular structure and inhibition theoretically.

Adsorption of the prepared DMDPP fits the Langmuir isotherm model. The inhibition efficiency of the prepared DMDPP amphipathic inhibitor is directly proportional to temperature increase. Polarization results reveal that the investigated DMDPP amphipathic compound behaves as a mixed-type inhibitor. EIS spectra produced one individual capacitive loop.

The originality is the preparation of cationic surfactants through a simple method, which can be used as corrosion inhibitors in oil production. The synthesized inhibitors were prepared from low-price materials. The work studied the behavior of the synthesized surfactants in inhibiting the corrosion of the steel in an acidic medium. Electrochemical and theoretical studies were presented, besides gravimetric and surface examination.

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H₂SO₄.

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10⁻³ M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

This work is original with the aim of finding new acid corrosion inhibitors.

In continuation to the previous work on copper (lignin/silica/fatty acids) (Cu-LSF) complex as a natural antioxidant/electrical conductivity agent for nitrile-butadiene rubber (NBR), this study aims to perform further investigations for NBR vulcanizates loaded with different concentrations of Cu-LSF complex, including swelling behavior and hardness properties, as well as evaluating their thermal stability via thermogravimetric analysis.

The behavior of Cu-LSF complex in NBR matrix was compared with that of the standard commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline/N-isopropyl-N′-phenyl-p-phenylenediamine [TMQ/IPPD]).

Results revealed that Cu-LSF complex can act as an effective reinforcing and hardening agent, with exhibiting fluid resistance, even when compared with the commercial antioxidants. In comparison with the previous studies on its Zn and Ca analogues and their behavior in different rubber matrixes, Cu-LSF complex showed higher values of hardness and less susceptibility for swelling, respectively. Moreover, Cu-LSF antioxidant activity becomes in accordance with the previous work.

The new Cu-LSF complex could be used as a green alternative to the commercial antioxidants (TMQ/IPPD) with introducing further advantages to the rubber matrix, such as hardening, fluid resistance and thermal stability.

The purpose of this paper is to present the physical context of the necropolis of Bat, look at its management by the Omani Ministry of Heritage and Culture (MHC), and discusse the challenges it is facing. It will also shed light on how the site of Bat is perceived by the local community and visitors.

The archaeological complex of Bat, al-Khutm, and al-Ayn was listed by the UNESCO as a world heritage site in 1988. Despite this classification, relatively little attention has been given to the management of this site. The author conducted interviews with representatives of the MHC in order to understand how this site is being managed, and the author uploaded an online public questionnaire to learn how the population is being educated about the importance of this heritage.

The results of this investigation revealed a surprisingly high level of public awareness about the importance of this site to the country socially, and economically. In spite of this awareness, the site is not visited frequently because it is not adequately equipped: a situation that was clearly outlined by the respondents. Suggestions were proposed in order to better integrate this site into the local development plans and the socio-economic growth of the whole region.

The originality of this research is that it took the site of investigation an archaeological site listed by the UNESCO for its outstanding universal value and contrary to what is expected, this site was “forgotten” in all development and management plans executed by the local and central government for almost two decades. It is also the first research about a site in Oman to address such issues and use these methods.

The purpose of this paper is to develop an eco-friendly corrosion inhibitor for mild steel in 1 M HCl.

A pharmaceutical drug acetyl G was investigated for its corrosion inhibition efficiency using weight loss method, potentiodynamic polarisation and electrochemical impedance spectroscopy.

The inhibition efficiency increased with increase in inhibitor concentration. Results from polarisation studies revealed mixed type of inhibition. Impedance studies, scanning electron microscopy and Fourier transform spectroscopy confirm the adsorption of inhibitor on the mild steel surface.

The drug acetyl G has sulphur and nitrogen atoms which effectively block the corrosion of mild steel and is non-toxic and has good inhibition efficiency.

This method provides an excellent, non-toxic and cost-effective material as a corrosion inhibitor for mild steel in acid medium.

Application of this drug as a corrosion inhibitor has not been reported yet in the literature. Replacing the organic inhibitors, this green inhibitor shows excellent inhibition efficiency. This is adsorbed excellently on the mild steel surface due to the presence of long chain and hetero atoms. Thus, the drug retards the corrosion reaction.

This study aims to deal with both the development and mechanical investigations of unsaturated polyester matrix (UPR) composites containing recycled polyethylene terephthalate (PET) fibers as new fillers.

UPR/PET fibers composites have been developed as mats by incorporating 5, 8, 13 and 18 parts per hundred of rubber (phr) of 6-, 10- and 15-mm length PET fibers from the recycling of postconsumer bottles. The mechanical and physical properties of the composites were investigated as a function of fiber content and length. A significant increase in stress at break and in ultimate stress (sr) were observed for composites reinforced with 5 and 8 phr of 15-mm length PET fibers. The Izod impact strength of UPR/mat PET fiber composites as a function of fiber rate and length showed that the 5 and 8 phr composites for the 15-mm length PET fiber have the optimal mechanical properties 13.55 and 10.50 Kj/m², respectively. The morphological study showed that the strong adhesion resulting from the affinity of the PET fiber for the UPR matrix. The ductile fracture of materials reinforced with 5 and 8 phr is confirmed by the fiber deformation and fracture surface roughness.

This study concluded that the PET fiber enhances the properties of composites, a good correlation was observed between the results of the mechanical tests and the structural analysis revealing that for the lower concentrations, the PET fibers are well dispersed into the resin, but entanglements are evidenced when the fiber content increases.

It can be shown from scanning electron microscopy micrographs that the fabrication technique produced composites with good interfacial adhesion between PET fibers and UPR matrix.