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Chicken feather particles reinforced rubber seed oil based polyurethane composites were produced and the physico-mechanical and microstructural analyses were studied. Casting method was used to produce the composites with varied weights of Chicken feather particles from 5 to 25wt% in steps of 5 wt%. The composites produced were analyzed for hardness, impact strength, tensile strength, density and water absorption properties according to ASTM standards. The density and impact strength were observed to decrease with increase in percentage weight of the chicken feather particles and this was attributed to the fact that the feathers have lower density than RSO-Polyurethane. Tensile strength and hardness of the composites were found to decrease at the intial stage (0 to 10 wt%) and later started to increase with percentage increase(15 to 25 wt%) of reinforment added. The microstructure reveals that there was a reasonable uniform distribution and bonding of chicken feather particles in the RSO-Polyurethane matrix.

The effects of electrode types on the mechanical properties of weldments produced from three steel samples made locally in Nigeria have been investigated. Oerlikon, Santan, Power Master and Magnum electrode samples were separately used to join Homus, Universal and Spanish steel samples. The chemical compositions of the steel samples, electrodes core and coating were obtained using spectrometer before using them for the research. Mechanical properties of the weldment produced were determined and compared to the unwelded samples. This was done in order to provide information on which combination of steel and electrode type will produce weldment with optimum mechanical properties. Oerlikon electrode produces weldments with optimum tensile strength of 508.25 N/mm² and impact energy of 152.76J for Homus Steel, it also produced highest tensile strength of 449.92 N/mm² and impact energy of 103.042J for Spanish Steels while Power Master Electrode produced weldment with highest tensile strength of 482.96N/mm² and impact energy of 137.033J for Universal Steel. The results show that single electrode type cannot produce weldment with highest properties for all the selected steel samples.

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake friction material (BFM).

Taguchi method was applied to design an experiment using three different discs of gray cast iron with different surface roughness, which is measured using optical profilometer. These discs were subjected to sliding against pins prepared with the developed non-asbestos BFM, using pin on disc friction and wear monitor.

The experimental results shows that the disc 2 (Ra = 3.77 µm) gives wear of 22.78 µm and coefficient of friction of 0.462, which is recommended for extreme brake performance. Analysis of Taguchi design revealed that the disc surface was most significant parameter among the parameters under study.

During braking, continuous sliding between the BFM and brake disc or drum not only results into wear of BFM but also changes the surface finish of the brake drum or disc. This leads to variation in surface topography of the drum or disc surface with application of brakes, which further affects the characteristics of the BFM.

The tribological performance of BFM depends upon the topography of the surface on which it was sliding. To get best performance of the non-asbestos friction materials, disc having moderate surface finish is recommended. Scanning electron microscope micrographs had shown the different plateaus formed and energy-dispersive X-ray spectroscopy spectra identified presence of different chemical elements prior to sliding of the pins surface over different discs surface topography.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0120/

The global construction industry has a history of poor project success, with evident and frequent overruns in cost and schedule. This industry is a highly interconnected and complex system in which the components, i.e. suppliers, contractors, end-users, and stakeholders, are delicately linked to each other, the community, and the environment. Therefore, defining and measuring project success can be challenging for sponsors, contractors, and the public. To address this issue, this study develops and analyzes a more comprehensive set of success criteria for medium and large construction projects.

After reviewing the existing literature, this study identified 19 success criteria for medium and large construction projects, which were categorized into five groups. The fuzzy decision-making trial and evaluation laboratory (fuzzy DEMATEL) method was used to gain further insight into the interrelationships between these categories and explain the cause-and-effect relationships among them. Next, this study applied the modified logarithmic least squares method to determine the importance weight of these criteria using the fuzzy analytic hierarchy process.

28 project managers working in the construction industries in Australia and New Zealand participated in this study. Results suggest that “project efficiency” and “impacts on the project team” are cause criteria that affect “business success,” “impacts on stakeholders,” and “impacts on end-users.” Effective risk management emerged as the most crucial criterion in project efficiency, while customer satisfaction and return on investment are top criteria in “impacts on end-users” and “business success.”

Although numerous studies have been conducted on project success criteria, multicriteria analyses of success criteria are rare. This paper presents a comprehensive set of success criteria tailored to medium and large construction projects. The aim is to analyze their interrelationships and prioritize them thoroughly, which will aid practitioners in focusing on the most important criteria for achieving higher success rates.

Low nickel austenitic stainless steel (ASS) has attracted much attention worldwide because of its economical price. This study aims to investigate the effect of different corrosive environments on the corrosion behavior of chrome-manganese (Cr-Mn) ASS. The tests were carried out as a function of H₂SO₄ concentrations, temperature and addition of ammonium thiocyanate (NH₄SCN) (0.01 M). Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were used to study the corrosion behavior of Cr-Mn ASS. It was observed that with increasing H₂SO₄ concentration, temperature and with the addition of NH₄SCN solution, icorr, icrit and ipassive values increased. EIS data show decreasing charge transfer resistance value with increasing concentration and temperature. Higher corrosion rate with increasing temperature and concentration of H₂SO₄ is related to the anions (SO₄²⁻), which is responsible for reducing the stability of passive films. With the presence of 0.01 M NH₄SCN thiocyanate (SCN⁻ anion), there is a higher dilution of the passive film resulting in a higher corrosion rate. Energy-dispersive spectroscopy (EDS) analysis reveals the adsorption of sulfur on the surface in NH₄SCN containing a solution. The significant presence of counter ions and the adsorbed sulfur species on the steel surface play a vital role in corrosion behavior.

All the experiments were performed on a 3 mm thick sheet of Cr-Mn ASS (202 ASS) in hot rolled condition. The samples were then annealed at 1,050°C for 1 h, followed by water quenching. For microstructural examination, they were electrochemically etched in 10 Wt.% oxalic acid solution at 1 amp for 90 s. A computer-controlled Potentiostat (Biologic VMP-300) was used. After the cell was set up, the working electrode (WE) was electrostatically cleaned at −1 V vs saturated calomel electrode (SCE) for 30 s to remove the air-formed film. Then, WE were allowed to attain stable open circuit potential (OCP) for 1 h, following by the EIS test and potentiodynamic polarization test. The polarization test was started from a cathodic potential (−1.2 V vs SCE) and continued up to an anodic potential (1.6 V vs SCE) a scan rate of 0.1667 mV/s. EIS experiment was conducted on the same instrument by using a sinusoidal AC signal of 10 mV in a frequency range of 1,000,000 to 0.01 Hz at OCP.

Potentiodynamic polarization graph shows that with the increase in sulphuric acid concentration. Increasing temperature from 20°C to 80°C in 0.5 M H₂SO₄ solution increases the corrosion rate (icorr) of Cr-Mn ASS. On the addition of 0.01 M NH₄SCN to the sulfuric acid solution (0.1, 0.5 and 1 M) the corrosion rate increases drastically almost four to five times. EDS and XRD analysis shows the presence of sulfur over the oxide film and preferential site for dissolution of Cr and Mn at the steel surface when NH₄SCN is added to the sulfuric acid solution.

A study on the corrosion behavior of Cr-Mn ASS is scanty according to the author’s knowledge. Therefore, the present study will investigate the corrosion behavior of Cr-Mn ASS on SO₄⁻² anions, temperature and the addition of SCN⁻ ion in sulfuric acid.

The present research aims to investigate how lean project management (LPM) and agile project management (APM) affect project performance outcomes in the construction sector in Jordan. This study focuses on six key project performance outcomes, namely cost, time, quality, client satisfaction, innovation and responsiveness.

The present study employed a quantitative approach to achieve the research objectives. Accordingly, a multi-item survey questionnaire was prepared to gather data from 392 project managers from construction companies in Jordan. The study’s model showed acceptable levels regarding reliability, validity, fit indices and discriminant validity. In order to test the hypotheses of this study, path analysis was employed using Amos 24.0 software.

LPM demonstrated a remarkably high positive impact on cost performance. It also positively affected quality performance and client satisfaction. However, LPM insignificantly affected time, innovation and responsiveness performance measures. On the other hand, APM showed a notably high positive impact on innovation and responsiveness. The findings also revealed that APM positively impacted quality performance and client satisfaction. In addition, APM negatively impacted cost performance and insignificantly impacted time performance.

This study is one of the first comprehensive studies to empirically examine the impact of both LPM and APM on various project performance outcomes in the construction industry in the context of a developing country. It reveals some similarities and differences between LPM and APM with regard to their impacts on project management outcomes. The findings are expected to guide managers in selecting the appropriate project management approach based on the desired performance outcomes. Accordingly, it offers important implications for project managers in construction companies.

Inefficiency dilemmas in project governance are caused by various risks arising from the characteristic of construction supply chain projects, such as poor project performance, conflicts between stakeholders and cost overrun. This research aims to establish a fuzzy synthetic evaluation (FSE) model to analyze construction supply chain risk factors. Corresponding risk mitigation strategies are provided to facilitate the improvement performance of ongoing construction supply chain projects.

A literature review is utilized to reveal the deficiencies of construction supply chain risk management. Thus, a total of five hundred (500) questionnaires are distributed to construction professionals, and four hundred and thirty-five (435) questionnaires are recovered to obtain the evaluation data of construction professionals on critical risk factors. Additionally, the FSE is used to analyze and rank the significance of critical risk factors. Finally, this research discusses nine critical risk factors with high weight in the model, and explains the reason for the significance of critical risk factors in the construction supply chain.

The questionnaire results show that the thirty-one (31) identified critical risk factors are verified by related practitioners (government departments, universities and research institutions, owners, construction units, financial institutions, design units, consulting firms). Thirty-one (31) identified critical risk factors are divided into common risks, risks from contractors and risks from owners. The most significant factors in the three categories, respectively, are “political risks,” “owner's unprofessional” approach and “cash flow.” Managing these risks can facilitate the development of the construction supply chain.

This paper expands the research perspective of construction supply chain risk management and complements the risks in the construction supply chain. For practitioners, the research result provides some corresponding measures to deal with these risks. For researchers, the research result provides the direction of construction supply chain risk treatment.

The purpose of this paper is to develop strategies for potential environmental impacts as a result of institutional arrangement and development of oil palm downstream industry both regionally and nationally.

The research location is in the areas potential for oil palm plantation development, either by plasma through BUMN and BUMS or self-supporting by the society. The research location will be divided into two parts, namely, the land area and the coastal area. The Riau land areas are Regency of Kampar, Rokan Hulu, and Kuantan Singingi, while Riau coastal areas are Regency of Pelalawan, Siak, Bengkalis, Indragiri Hilir, Indragiri Hulu and Rokan Hilir. Both research areas have different productivity due to the different soil fertility levels. The sustainability level of oil palm plantation from the socio-economic and environmental aspects is analyzed using the multi-dimensional scaling approach modified into Rapid Appraisal-Index Sustainability of Palm Oil Management.

In Riau Province, the development of oil palm is quite rapid. This is reasonable for several reasons which include the following supporting factors: the geographical condition of the Riau region is very supportive; the high demand for palm oil derivative products; the existence of market guarantee for oil palm farmers; the higher income oil palm generates than other plantation crops; and the relatively flat area. Most of the problems faced by oil palm farmers are the use of less good seeds, the length of the fruit laying at the location of the plantation, the inadequate production road, the relatively far distance to palm oil mill (POM) (National Agency of Drug and Food Control), the tendency of determining the unilateral revenue of the POM, the collectively measurement of revenue and the general revenue information. The development of oil palm plantations has created an entrepreneurial capability for farmers who are able to capture business opportunities in the agricultural sector, especially the plantation sub-sector.

The originality of this paper shows the comprehensively control strategy, potential of environmental impact and palm oil plantation. The method used for data collection was rapid rural appraisal method because accurate information is needed in a limited time as it relates to decisions related to village development that must be taken immediately. The study area was conducted in Riau Province because Riau Province is one of the biggest palm oil producers in Indonesia. The study sites will be divided into two, namely, the land area and the coastal area.

The Hausawas are the largest ethnic group in sub-Saharan Africa, and significantly influence trade and development in the region (Limbs & Fort, 2000; Sabiu & Sarwar, 2019). They are highly entrepreneurial and have participated in international trade for centuries, particularly along the trans-Sahara. Historically, the Hausas have been considered one of Africa’s major trading powers. As of the twelfth century ad, their trading prowess was only rivalled by that of the Mali Empire and the Kanem-Bornu Empire (Sabiu, Zainol, & Abdullah, 2019).

Much can be learnt from indigenous Hausa culture of responsible management. Unfortunately, due to its multiple acculturative history, many aspects of this culture have not been properly preserved. Using historical sources, proverbs, and folktales, the author reclaims key cultural practices, values, and attitudes of the Hausa people that promote responsible management. Prominent amongst these values are kirki, respect for human dignity, spirit of work, being responsible, and honesty.

This study aims to determine the factors and dynamic systems behaviour of essential medicine stockout in public health-care supply chains. The authors examine the constraints and effects of mental models on medicine stockout to develop a dynamic theory of medicine availability towards saving patients’ lives.

This study uses a mixed-method approach. Starting with a survey method, followed by in-depth interviews with stakeholders within five health-care supply chains to determine the dynamic feedback leading to stockout and conclude by developing a network mental model for medicines availability.

The authors identified five constraints and developed five case mental models. The authors develop a dynamic theory of medicine availability across cases and identify feedback loops and variables leading to medicine availability.

The need to include mental models of stakeholders like manufacturers and distributors of medicines to understand the system completely. Group surveys are prone to power dynamics and bias from group thinking. This survey’s quantitative output could minimize the bias.

This study uniquely uses a mixed-method of survey method and in-depth interviews of experts to assess the essential medicine stockout in Nigeria. To improve medicine availability, the authors develop a dynamic network mental model to understand the system structure, feedback and behaviour driving stockouts. This research will benefit public policymakers and hospital managers in designing policies that reduce medicine stockout.