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A sheet metal forming simulation code has been developed, based on the explicit time integration scheme and Mindlin shell theory. It has been used for the analysis of a number of industrial parts. After recalling some modelling issues, this paper describes an industrial methodology based on the experience of those analyses. The aim of the methodology is to provide, at early design stage, information on the product formability with a workload and lead time adapted to the design delays. Concurrently 2D analyses, critical zones studies and coarse mesh global investigations can be used, with a flexible number of iterations, prior to full refined analyses of the forming process. The application of the methodology on several industrial examples is discussed.

The purpose of this paper is to evaluate the physicochemical properties, fatty acids, tocopherols, and polyphenols of Algerian argan oil.

The argan oil was extracted from the kernel by an organic solvent, the n‐hexane. Several methods and techniques (spectrophotometric, titrimetric, refractometric, and chomrtographic (CPG/high‐performance liquid chromatographic – HPLC) were used to characterise to argan oil.

The argan oil was yellow oil with faintly marked smell and flavour. The physicochemical analysis showed that the oil was pure, fresh, not siccative and rich in C₁₈ medium chain unsaturated fatty acids, particularly the oleic acid. A HPLC and gaseous phase chromatography methods were developed for the quali‐quantitative analysis of α‐tocopherol and fatty acids composition, respectively.

This highlight shows that the composition of argan oil is oleic‐linoleic type rich in α‐tocopherol (20 mg/kg). The phenolic fraction known for its antioxidant properties ranges from 30 to 50 mg/kg. The argan oil is mainly rich in antioxidant compounds such as phenolic compounds and α‐tocopherol. Argan oil is rich in unsaturated fatty acids, tocopherol and phenolic compounds.

Considering its rich composition in antioxidant compounds and essential fatty acid, argan oil has been used for a long time as a food and for body care, prevention and treatment of cardiovascular and some cancers diseases. A deep knowledge of the chemical composition of argan oil will certainly show that is has a high‐nutritional potentiality and is claimed to have favourable medicinal and cosmetic properties.

No such research has been carried out on the argan oil extracted from Argania spinosa (L.) of Algeria. The present work was undertaken to study the physicochemical and nutritional properties of the argan oil.

Academics recently identified a lack of research regarding who should guide interactions in virtual social networks when risks appear. Data shows that organizers are usually less active than other users in this context, which can lead to negative reactions among attendees. This research examines if and how virtual social network communication guided by an official source (vs a nonofficial source vs control group) reduces perceived crime risks and trust before the event, leading to lower ambivalence and higher intention to attend. The study was conducted in Colombia, a country where many individuals face this type of risk.

First-year university students (N = 210) from Colombia were invited to a “Welcome Cocktail”. Two weeks before the cocktail, they were divided into three groups (70 per condition) to receive information. In Group 1, participants were invited to be part of a WhatsApp group administered by one of the organizers. In Group 2, they participated in a WhatsApp group administered by a student. Group 3 was the control (i.e. no virtual communication established before the event). One week after the meeting, they were gathered again and answered a questionnaire, which measured perceived crime risk, trust, ambivalence and intention to attend.

Participants in the WhatsApp group administered by an official source perceived lower risk and higher trust in the organizers, which led to lower ambivalence towards the event and higher intention to attend it. The relationship between ambivalence and intention to attend is moderated by the nationality of the participants (locals vs foreigners), such as, at equal levels of ambivalence, foreigners show lower intention to attend the event.

This is the first study that compares different approaches on a virtual social network to reduce perceived crime risk in event management. The results present new findings on how the presence of an official source can mitigate this risk, and which potential attendees (i.e. locals vs foreigners) are especially benefited from it. The findings are particularly useful for managers in regions where attendees face crime risks every day, and might feel low trust towards public and private institutions, such as in Colombia.

This paper reviews Tunisia's movement to an agricultural export strategy as a method of creating rural economic growth. Having explained the economic logic and pitfalls of agro-export production, it then evaluates the Tunisian effort to develop an agricultural export industry first in general and then using a specific case study of strawberry adoption in Cap Bon. Results show that Tunisia has been successful in increasing agro-export production, though as yet not in using it to create equitable rural growth.

The study analysed the factors influencing real estate firms' (REFs) decision to adopt virtual reality (VR) technology using the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method. This was done to enhance the practice of real estate agency in Nigeria.

Data were elicited from eight real estate experts. These experts were heads of the agency department of firms that had been in existence for a minimum of five years in the Lagos property market. The data analysed in this study were collected with the aid of a questionnaire.

The result revealed that use intention was influenced by performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, price value and UB. Also, facilitating conditions, habit and use intention did not influence use behaviour. Overall, six constructs, which include price value (R_i − C_j value = 0.1284), use behaviour (R_i − C_j value = 0.0666), social influence (R_i − C_j value = 0.0583), facilitating conditions (R_i − C_j value = 0.0323), performance expectancy (R_i − C_j value = 0.0196) and effort expectancy (R_i − C_j value = 0.0116), were significant predictors of the factors influencing the decision of REFs to adopt VR. Of these constructs, the R_i − C_j values indicated that price value had the highest causative influence.

The result of this study will bring REFs to the consciousness of the factors that could affect their adoption of VR technology. This study will also assist the Nigerian Institution of Estate Surveyors and Valuers in appropriately enlightening REFs on the integration of VR technology into the agency practice especially at this time when all health protocols and guidelines need to be observed to help flatten the curve of the Covid-19 pandemic.

This study is the first to have an insight into the analysis of the factors influencing REFs' decision to adopt VR technology using the DEMATEL method.

Integrated solar combined cycle (ISCC) using parabolic trough collector (PTC) technology is a new power plant that has been installed in few countries to benefit from the use of hybrid solar-gas systems. The purpose of this paper is to investigate the challenges in modeling the thermal output of the hybrid solar-gas power plant and to analyze the factors that influence them.

To validate the proposal, a study was conducted on a test stand in situ and based on the statistical analysis of meteorological data of the year 2017. Such data have been brought from Abener hybrid solar-gas central of Hassi R’mel and used as an input of our model.

The proposal made by the authors has been simulated using MATLAB environment. The simulation results show that the net solar electricity reaches 18 per cent in June, 15 per cent in March and September, while it cannot exceed 8 per cent in December. Moreover, it shows that the power plant responses sensibly to solar energy, where the electricity output increases accordingly to the solar radiation increase. This increase in efficiency results in better economic utilization of the solar PTC equipment in such kind of hybrid solar-gas power plant.

The obtained results would be expected to provide the possibility for designing other power plants in Algeria when such conditions are met (high DNI, low wind speed, water and natural-gas availability).

This paper presents a new model able to predict the thermal solar energy and the net solar-electricity efficiency of such kind solar hybrid power plant.

This research examines factors influencing the adoption of crop and revenue insurance. This is accomplished by estimating a multinomial logit model of insurance choices facing U.S. farmers. Results indicate significant differences in the probabilities of adoption of each insurance plan. The levels of selected explanatory variables, such as operator’s education level, debt‐to‐asset ratio, off‐farm income, soil productivity, participation in production and marketing contracts, and type of farm ownership, appear to be the determinants of the probability of having adopted each insurance plan.

Behavioral intention models are assumed to be universally applicable; however, recent criticisms have questioned their application among non‐Western subjects. It is argued that models that posit constructs that represent and measure the cultural nature of evaluative and normative latent constructs will best model intention formation in a culture. Thus, emic measures of etic latent constructs are required. A review of culturally‐influenced differences in reasoning processes between Chinese and Americans provides a theoretical basis to explore these models with samples from two cultures. Models considered Western, Oriental, and universal were compared with Hong Kong and US subjects. As predicted, the most Western model fit the USA data best and the most Oriental model fit the Hong Kong data best. Also as predicted, the measures of evaluation most representative of emic thought processes were most related to intention formation. Results suggest that the BI framework is applicable across cultures, yet must be operationalized with the distinctive thought processes of each culture in mind.

The purpose of this study is to review the role of knowledge management (KM) in disaster management and crisis. Disaster causes many detrimental impacts on human lives through loss of life and damage to properties. KM has been shown to dampen the impact of the disaster on the utilization of knowledge among agencies involved and the local communities impacted by disasters.

Through a bibliometric methodology (co-citation, bibliographic coupling and co-word analysis), this study presents significant themes in the past, current and future predictions on the role of KM in disaster management. In this review paper, 437 publications were retrieved from the Web of Science and analyzed through VOSviewer software to visualize and explore the knowledge map on the subject domain.

Findings suggest that the significant themes derived are centralized to disaster preparedness during disaster and disaster postrecovery. This review presents a state-of-art bibliometric analysis of the crucial role of KM in building networks and interconnection among relevant players and stakeholders involved in disaster management.

The main implication of this study is how the authorities, stakeholders and local community can integrate the KM system within the three stages of disasters and the crucial role of technologies and social media in facilitating disaster management.

To the best of the authors’ knowledge, this is the first study to present a bibliometric analysis in mapping KM’s past, present and future trends in disaster management.

The purpose of this paper is to develop a partial equilibrium model for the Tunisian dairy sector according to “quantity formulation” and “price formulation” and to show their equivalence under the assumption of perfect competition.

This model incorporates domestic policies, that is, producers' price support and subsidies to milk collection centres and trade policies, that is, TRQ and ad valorem tariffs. The authors illustrate theoretically and numerically how to incorporate the minimum price policy at the farm level for the Tunisian dairy sector according to the price formulation approach.

Two scenarios for the removal of a minimum price policy are analysed and show that producers' surplus loss varies between 78.6 and 127.8 million dinars. The overall welfare implications of removing a minimum price policy are negative and range between 13.3 and 18.2 million dinars.

This study could not include all of the detailed factors in the Tunisian dairy sector.

Based on the numerical results obtained in the study, the authors recommend that public authorities maintain the minimum price policy because it prevents a decrease in raw milk producers' surplus. Moreover, this policy is effective because it generates excess raw milk production, estimated at 28.23% in 2010, that can be used for various homemade dairy products. Under an effective minimum price policy, the formal processing sector absorbs all the excess raw milk only if the public authorities allocate grants to encourage investment in new milk collection centres and in milk drying equipment, especially in disadvantaged rural regions. The latter economic policy coupled with a minimum price policy not only guarantees a higher income for raw milk producers but also may represent a development factor for underprivileged rural areas.