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Large amounts of uranium, radium and radium products are redistributed throughout the environment owing to the use of phosphate fertilizers. Potential radiological impacts resulting from direct exposure, inhalation and ingestion of foods grown with fertilizers are discussed. This paper describes a simple method to measure exhalation rate of ²²²RN from phosphate fertilizers, clay and potatoes in a laboratory and in a more economical way. Three Egyptian factories of phosphate fertilizers were selected in this study (Assuit, Abu Zaable and Kafr El Ziat).

To determine the radon emanation rates of common partition materials in Hong Kong.

An initial slope of radon gas growth against time and a mass balance analysis can be used to quantify the magnitude of these rates from different types of partition materials. In particular, the radon‐222 emanations from boards of calcium silicate, gypsum and lightweight concrete were measured experimentally in a small impervious radon chamber.

The radon‐222 emanations from boards of calcium silicate, gypsum and lightweight concrete were measured experimentally in a small impervious radon chamber, and expressed as becquerels per square meter per hour of air (Bq m⁻² hr⁻¹). The rates found were 2.43, 0.22 and 0.46 Bq m⁻² hr⁽¹ respectively. Comparing with the emanation rate and the quantities of radon emitting construction materials in Hong Kong, these three partition materials have a low radon emitting level.

The model parameters used in the study were not exhaustive and were determined from samples of materials used in Hong Kong.

A useful source of reference for determining the radon emanation rates of common partition materials used in building developments. The results can be used to identify the exposure risk of radon in buildings.

This paper proposes a mathematical model of radon emanation rates of common partition materials. The model offers practical helps to professionals planning, designing and managing the selection of building materials in buildings.

Risk management has emerged as a critical issue in operating a supply chain effectively in the presence of uncertainties that result from unexpected variations. Assessing and managing supply chain risks are receiving significant attention from practitioners and academics. At present, the ceramic industry in Bangladesh is growing. Thus, managers in the industry need to properly assess supply chain risks for mitigation purposes. This study aims to identify and analyze various supply chain risks occurring in a ceramic factory in Bangladesh.

A model is proposed based on a fuzzy technique for order preference using similarity to an ideal solution (fuzzy-TOPSIS) for evaluating supply chain risks. For this, 20 supply chain risk factors were identified through an extensive literature review and while consulting with experts from the ceramic factories. Fuzzy-TOPSIS contributed to the analysis and assessment of those risks.

The results of this research indicate that among the identified 20 supply chain risks, lack of operational quality, lack of material quality and damage to inventory were the major risks for the ceramic sector in Bangladesh.

The impact of supply chain risks was not shown in this study and the risks were considered independent. Therefore, research can be continued to address these two factors.

The outcome of this research is expected to assist industrial managers and practitioners in the ceramic sector in taking proactive action to minimize supply chain risks. A sensitivity analysis was performed to determine the relative stability of the risks.

This study uses survey data to analyze and evaluate the major supply chain risks related to the ceramic sector. An original methodology is provided for identifying and evaluating the major supply chain risks in the ceramic sector of Bangladesh.

Radon is responsible for approximately 50 per cent of public exposure to environmental radiation. The purpose of this paper is to quantitatively assess indoor radon levels in Cyprus.

In total, 500 passive radon detectors were used to estimate radon levels in the areas of Nicosia (capital), Paphos, Nisou and Famagusta. A total of 240 different public and private buildings were randomly selected in the above districts and two passive radon detectors were placed inside each building. The detectors were collected on average, three months following placement.

The average radon level from all passive detectors was 53.7 and 49.2 Bq/m3 after excluding the seven highest values. The two highest measurements were observed in Paphos, Tsada-Kili elementary school (429 Bq/m3) and Emba, Paphos district (410 Bq/m3), respectively. Differences were also seen in public buildings compared to private buildings (p=0.058). In addition, rural buildings had higher radon levels compared to urban buildings (p=0.001). Predictive multilevel regression models for logarithmic radon levels were employed and differences were seen on point estimates regarding building- and district-level radon measurements. Most of the random variability observed was due to building-level variation.

Residents from different geographic areas in Cyprus are reassured about the safety of indoor radon levels in public and private buildings.

The estimation of indoor radon levels was done by the optical microscopy technique using a specific mathematical formula. Observed radon levels do not raise concern regarding residents’ radon exposure in Cyprus. Paphos district and Nisou area may require further investigation.

The purpose of this research is to empirically investigate the impact of organizational culture on implementing customer relationship management (CRM) in the hotel industry.

The research is conducted with a quantitative approach and a questionnaire adapted from Denison Organizational Culture Survey, and the Mendoza CRM model is the research instrument. The questionnaire was administered among 346 managers of a chain hotel in the UK. Gathered data were subjected to correlation and multiple regression analyses.

The correlation analysis demonstrates that organizational culture factors of adaptability, consistency, staff involvement and mission have a positive significant impact on CRM implementations. The multiple regression analysis further showed that though CRM implementation is highly correlated with these four factors, its successful implementation is not dependent on all of them.

The research is conducted in the frame of a case study where a UK chain hotel is selected; therefore, the findings cannot be generalized to a larger population. This research is conducted in the context of hotel industry and the result might be different for other industries. Due to the limitation in access to all employees, only managers were selected as the sample of the study and future studies with all staff may show different results.

Organizational culture readiness is one of the most important requirements in CRM implementation initiatives. The results of this study will benefit hotel managers in measuring their organizational culture and improve it toward better CRM outcomes.

Previous studies on organizational culture and CRM with qualitative approaches have tried to highlight the role of organizational culture on CRM implementation or some have attempted to identify the organizational culture factors with potential impact on CRM implementations. However, very few of these studies have empirically investigated the impacts of organizational culture on CRM implementation, and this is the first study that empirically investigates this impact in the context of the hotel industry.

Existing analytical methods for the evaluation of fire safety of reinforced concrete (RC) structures require extensive knowledge of heat transfer calculations and the finite element method. This paper aims to propose a rational method to predict the axial capacity of RC columns exposed to standard fire.

The average temperature distribution along the section height is first predicted for a specific fire scenario. The corresponding distribution of the reduced concrete strength is then integrated to develop expressions to calculate the axial capacity of RC columns exposed to fire from four faces.

These expressions provide structural engineers with a rational tool to satisfy the objective-based design clauses specified in the National Code of Canada in lieu of the traditional prescriptive methods.

The research is limited to standard fire curves and needs to be extended to cover natural fire curves.

This paper is the first to propose an accurate yet simple method to calculate the axial capacity of columns exposed to standard fire curves. The method can be applied using a simple Excel sheet. It can be further developed to apply to natural fire curves.

The design of buildings for fire events is essential to ensure occupant safety. Supplementary to simple prescriptive methods, performance-based fire design can be applied to achieve a greater level of safety and flexibility in design. To make performance-based fire design more accessible, a time-equivalent method can be used to approximate a given natural fire event using a single standard fire with a specific duration. Doing so allows for natural fire events to be linked to the wealth of existing data from the standard fire scenario. The purpose of this paper is to review and assess the application of an existing time-equivalent method in the performance-based design of reinforced concrete (RC) beams.

The assessment is established by computationally developing the moment-curvature response of RC beam sections during fire exposure. The sectional response due to natural fire and time equivalent fire are compared.

It is shown that the examined time equivalent method is able to predict the sectional response with suitable accuracy for performance-based design purposes.

The research is the first to provide a comprehensive evaluation of the moment-curvature diagram of RC beams using time-equivalent standard fire scenarios that model realistic fire scenarios.

Fire safety is a pivotal requirement in building codes. Prescribed design criteria have been the norm to achieve it, which imposes limitations on engineers, including the inability to accommodate new solutions/materials. The shift towards performance-based design offers the potential to address shortcomings of the prescribed design. However, this shift also significantly increases the workload on structural engineers without a corresponding increase in their engineering fees. Simplified design tools are needed to assist engineers in this transition.

The paper is divided into sections investigating equivalent standard fire duration, thermal deformations, flexural behaviour and shear capacity of flat slabs when exposed to fire. The first section conducts a parametric study correlating equivalent and realistic fire durations using the average internal temperature profile (AITP) method, resulting in statistical equations estimating equivalent fire duration. The second section evaluates thermal deformations and flexural behaviour through a parametric study considering various parameters. This section results in statistical equations estimating thermal deformations and flexural behaviour of flat slab sections during fire exposure. The final section focuses on shear capacity, developing simplified heat transfer formulas and statistical equations predicting compression zone depth reduction. The section presents methodologies predicting flat slab sections' one-way and two-way shear capacities during fire exposure.

Structural engineers can use the proposed methods for daily design work without applying complex heat transfer calculations. When the equivalent standard fire duration is utilized, a flat slab’s thermal deformations, flexural behaviour and shear capacity under an actual fire condition can be calculated. As such, the methods would be highly beneficial in assessing the structural integrity of a building during an active fire incident.

The paper provides engineers with the tools required to evaluate the safety of flat slab sections during fire exposure. The methodologies presented in the paper enable engineers to use performance-based design for slab sections by (1) converting any real fire scenario to a standard fire with an equivalent duration, (2) assessing their thermal behaviour, (3) evaluating their flexural behaviour and (4) evaluating their flexural and shear capacities. The paper concludes with a case study example demonstrating the detailed application of the developed methods.

The recent world refugee crisis has mobilized societies all around the globe and has led to the multiplication of initiatives calling for support to refugees. Given the fact that one-third of the displaced population were children, measures for their immediate integration into schools were taken in most European countries. Although in Greece children with refugee experience first attended schools in 2017, teachers were not adequately prepared to cope with students who had lacked schooling for many years and with whom they couldn’t easily communicate due to language barriers. New teaching methodologies were needed for pre- and in-service teachers to bridge the gap between existing knowledge and the needs of refugee students. In this context, the authors designed a project called “Literacy through Drama” in the reception class of a public school in Volos, Greece involving 12 pre-service teachers. The findings of the study highlight that drama-based informal learning may provide opportunities for pre-service teachers to develop valuable knowledge about learners in authentic settings and pedagogy in practice. Faculties of education could facilitate effective community partnerships with organizations that work with refugee families and children and the school system and propose holistic curricula which include refugee student experiences. Moreover, pre-service teachers could gain skills and knowledge in supporting refugee students, identify refugee students’ needs, communicate in creative ways, and overcome deficit beliefs about refugee students.

For any given customer, his/her profitability for a business enterprise can be estimated by the so-called customer lifetime value (CLV). One specific goal for many enterprises consists in maximizing the aggregated CLV associated with its set of customers. To achieve this goal, a company uses marketing resources (e.g. marketing campaigns), which are usually expensive.

This paper proposes a formal model of the Customer Life Value problem inspired by the uncapacitated facility location problem.

The computational experiments conducted by the authors illustrate the potential of the approach when compared with a standard (non-algorithm-supported) one.

The approach leads up to the economic trade-off between the volume of the employed resources and the aggregated CLV, i.e. the higher the number of resources utilized, but also the higher the cost of achieving this level of lifetime value. Hence, the number of resources to be “activated” has to be decided, and the effect of each of these resources on each CLV will depend upon how “close” the resource is from the corresponding customer (i.e. how large will the impact of the active resource on the customer).