Risk reality vs risk perception

Here we explore new tools to improve risk communication within built infrastructure procurement by considering quantitative engineering risk and perceived risk associated with groups of stakeholders. In particular, the perceived risk is assumed to be dependent on motivational values that individuals identify with. The motivational values are evaluated using 40 questions Swartz Portrait Value Questionnaires. Ten hazards are considered in a survey to identify two dimensions, fear and unknown for a specific group of stakeholders. From the outcomes, it was identified that using a hybrid approach to establish the motivational values and risk perceptions for the stakeholder group risk communication could be improved. Furthermore, the outcomes could be used to target information to stakeholders or intervene to ensure that infrastructure performs according to expectation. As a result, it could become possible to revise what are currently inconsistent acceptable risk levels that have been embedded in regulatory documentation

Risk perception vs. risk reality

Here we explore the feasibility of a rationalized approach to risk within construction procurement by considering explicit engineering risk and perceived risk that selective group of stakeholders share. In particular, the perceived risk is assumed to be dependent on motivational values that individuals identify with. The motivational values are evaluated using 40 questions Swartz Portrait Value Questionnaires. 10 selected hazards are considered in a survey to identify measure of fear and unknown that stakeholders recognize and data analysed. From the outcomes it was identified that by using the alternative approach to establish risk perception the priorities for the stakeholder group in terms of risk can be recognized. Furthermore, the outcomes could be used to target information to stakeholders or intervene to ensure that infrastructure performs according to expectation. As a result, it could become possible to revise what are currently inconsistent acceptable risk levels that have been embedded in active regulatory documentation

Stochastic process deterioration modelling for adaptive inspections

In this paper we have considered an option to model deterioration process for infrastructure components using stochastic process representation as an alternative to random variable modelling that is prevalent approach when uncertainty is taken into account. In particular, we have identified that a Gamma process represents a very simple and effective method to establish consistent deterioration models for structures that are subject to inspection. As a result of such approach we see an opportunity to establish adaptive inspection regimes that would account much better for the structure specific deterioration path, site specific environment, in service inspection outcomes, inspection technique effectiveness, etc. An example is presented to demonstrate deterioration modelling and further work is identified

Imperfect inspection characterization for gamma process structural deterioration model

The deterioration of infrastructure facilities such as bridges has raised concerns over objective methodology to quantify the changes in their safety levels during the service life. In this paper the novel modeling of existing reinforced concrete structures likely future deterioration of strength is of interest. It is assumed that inspection outcomes are the source of data about the deterioration process and should provide help with the updating of the deterioration model with respect to the current structural condition. However, the inspection outcomes are associated with uncertainties that need to be taken into account for deterioration modeling. Sample reinforced concrete structure deterioration process is characterized as a time-dependent, non-negative and incremental process. In this paper we follow recent developments and the continuous gamma process has been adopted to represent the mathematical model of the deterioration process. In the current study two data sources were considered, the expert opinion, which is considered to reflect 'perfect inspection' and data obtained through scheduled inspections as 'imperfect inspection'. This paper reports on early development of the model to quantify the measurement error as inspection uncertainty and to establish continuous gamma process parameters for future deterioration prediction

An adaptive methodology for risk classification of small homogeneous earthfill embankment dams integrating climate change projections

This paper presents the application of the advanced probabilistic slope stability model with precipitation effects developed to assess the performance of small homogeneous earthfill embankment dam slopes, when exposed to future seasonal precipitation scenarios. Here, the UK's latest probabilistic climate model known as UKCP09 is applied. To reflect the critical conditions conducive to slope failure, a benchmark has been developed to identify the change, if any, in the risk classification of the slope's performance level due to precipitation. Thus, enabling the reassessment of the dam's risk classification, as categorised by the Flood and Water Management Act 2010. Such an approach could therefore be well placed to support and enhance the decision-making process, its impact on the public, especially in relation to future climate effects

Embankment dam probabilistic assessment for climate scenarios

For small earthfill dams exposed to climate scenarios such as those defined in UKCP09, deterministic assessments are insufficient, and more sophisticated models are required. This paper presents a hybrid probabilistic methodology that quantitatively measures the notional reliability index against upstream and downstream slope failure for such dams exposed to variable precipitation. Upstream and downstream slope stability are selected here as representative significant limit states governing the dam's long-term performance. The governing equations for the limit states are defined using the sliding-block method incorporating the effects of infiltration through the embankment. Using standard and sloping Green–Ampt and closed-form van Genuchten methods, the rainfall effects on soils with variable saturation are considered, and the standard first-order second moment method is applied. The probabilistic model encompasses uncertainties associated with soil properties, dam geometry and rainfall parameters. The paper demonstrates notional reliability indices for the dam for selected precipitation scenarios. A benchmark is developed that reflects the critical conditions conducive to slope failure. The paper reflects on the implication of inclusion of probabilistic climate models for associated risks. Therefore the analysis is an effective new management tool for risk assessment of embankment dams as categorised by the Flood and Water Management Act 2010

Stochastic process model for timber-concrete composite beam deterioration

The aim of this paper is to present a new stochastic process model that will capture the true nature of deterioration of timber-concrete composite beams. Composite elements such as timber-concrete composite sections are designed to take advantage of compatibility of materials under sustained loading. Applied sustained load on timber-concrete composite structures causes gradual increase of deformation and deflection. In particular for timber-concrete composite beams, component materials will deteriorate at different pace over the life-cycle. In order to enable efficient management of structures in terms of required maintenance, repair and/or replacement, it is essential to be able to capture the uncertain nature of the deterioration process. We focus on modeling the deterioration of mid-span deflection of the timber-concrete composite beam over long term under sustained load. As the increasing deflection of the timber-concrete composite beam over time is generally uncertain and non-decreasing, it can best be regarded as a continuous gamma process. Examples of continuous gamma process representation have been included

Gamma process model for timber-concrete composite beam deterioration prediction

This paper presents the application of the advanced probabilistic slope stability model with precipitation effects (APSMP) developed to assess the performance of small homogeneous earthfill embankment dam slopes, when exposed to future seasonal precipitation scenarios. Here, the UKs latest probabilistic climate model known as UKCP09 is applied. To reflect the critical conditions conducive to slope failure, a benchmark has been developed to identify the change, if any, in the risk classification of the slope’s performance level due to precipitation. Thus, enabling the reassessment of the dam’s risk classification, as categorized by the Flood and Water Management Act 2010. Such an approach could therefore be well placed to support and enhance the decision making process, its impact on the public, especially in relation to future climate effects

ANALYSIS OF INDIVIDUAL CHARACTERISTICS IN PRODUCTION ON A SHEEP FARM IN THE MUNICIPALITY OF ROGATICA AND FOCA

Analysis was conducted on the territory of Rogatica and Foca. The analysis included 30 randomly selected farms. Twenty sheep farms raising Pramenka different strains (Vlasic and Herzegovinian strain), while the other ten sheep farms raising sheep Württemberg race and crossed Tsigai, Romanovska and Texel sheep breeds. were analyzed by the following characteristics: number of household members, the total number of sheep, the total area of agricultural land, the selling price of 1 kg of lamb and the average weight of lambs during the sale and conducted a descriptive analysis of the results. Depending on the features found numerous smaller or larger variations. The greatest differences were recorded with the characteristics of the soil, bares the herd and the number of household members. The selling price and weight of lambs in the sale of unique values and indicate the possibility of a unique production technology and the natural and market conditions

CORRELATION BETWEEN INDIVIDUAL PRODUCTION AND SLAUGHTER TRAITS OF COBB 500 AND HUBBARD

The aim of this work is to define the correlation between the proportion of breast, thigh and drumstick relative to the weight before slaughter in relation to the weight of dressed grill ready carcass in two broiler hybrids (Hubbard and Cobb 500) at different ages (40 or 42 days). Positive correlation between the carcass prior to slaughtering and share of breasts, thighs and drumsticks, at the age of 40 (Hubbard) and 42 (Cobb 500) days, was monitored in Cobb 500 (except between the carcass before slaughter males and stakes thighs and drumsticks), and in line Hubbard (except between the carcass prior to slaughtering and share of breast in both sexes collectively). Positive correlation between the carcass processed for barbecue and shares breasts, thighs and drumsticks of the genotypes, in Cobb 500 (except between the carcass prior to slaughter men throat and share thighs and drumsticks), and Hubbard (except between the carcass prior to slaughtering and share of breast in both sexes collectively) at the age of 40 (Hubbard) and 42 (Cobb 500) days, was monitored