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This study aims to determine the maximum extent of damage in the threat zones, the result of a catastrophic failure in one liquefied petroleum gas storage sphere, located in storage and transfer center in Hassi R’Mel city, Algeria.

To reach the desired results, we relied on ALOHA® v. 5.4.7 software (Areal Locations of Hazardous Atmospheres) for accidents simulation, and on Google Earth as an output tool to show results on the city map.

The results prove that the city of Hassi R’Mel is almost completely threatened by thermal effects resulting from a boiling liquid expanding vapor explosion phenomenon, which can reach a distance of 3.9 km.

Determining the extent to which the damages resulting from an industrial accident may reach is of great importance in preventing industrial hazards, as well as in decision-making in the field of urbanization.

The risk control is an unavoidable step in the risk management process. It is materialized by concrete actions of risks reduction in order to decrease their likelihood and/or their severity and also to preserve the environment. The paper aims to discuss this issue.

The main goal of the proposed methodology is to define the safety barriers (SB) that can be realized and their contribution to reduce major accidents scenarios that may occur in high-risk establishments.

In the proposed methodology, the authors present a combination of methods to prove the effectiveness of SB in an industrial installation.

The proposed methodology is a valuable help to industrialists to secure their industrial activities and preserve the environment at the same time.

The retained methods are often used separately for audit purposes or risk assessments of high-risk industrial facilities. In this paper, three methods have been selected and articulated in an approach for a better evaluation of risk control level.

This study aims to improve the reliability of emergency safety barriers by using the subjective safety analysis based on evidential reasoning theory in order to develop on a framework for optimizing the reliability of emergency safety barriers.

The emergency event tree analysis is combined with an interval type-2 fuzzy-set and analytic hierarchy process (AHP) method. In order to the quantitative data is not available, this study based on interval type2 fuzzy set theory, trapezoidal fuzzy numbers describe the expert's imprecise uncertainty about the fuzzy failure probability of emergency safety barriers related to the liquefied petroleum gas storage prevent. Fuzzy fault tree analysis and fuzzy ordered weighted average aggregation are used to address uncertainties in emergency safety barrier reliability assessment. In addition, a critical analysis and some corrective actions are suggested to identify weak points in emergency safety barriers. Therefore, a framework decisions are proposed to optimize and improve safety barrier reliability. Decision-making in this framework uses evidential reasoning theory to identify corrective actions that can optimize reliability based on subjective safety analysis.

A real case study of a liquefied petroleum gas storage in Algeria is presented to demonstrate the effectiveness of the proposed methodology. The results show that the proposed methodology provides the possibility to evaluate the values of the fuzzy failure probability of emergency safety barriers. In addition, the fuzzy failure probabilities using the fuzzy type-2 AHP method are the most reliable and accurate. As a result, the improved fault tree analysis can estimate uncertain expert opinion weights, identify and evaluate failure probability values for critical basic event. Therefore, suggestions for corrective measures to reduce the failure probability of the fire-fighting system are provided. The obtained results show that of the ten proposed corrective actions, the corrective action “use of periodic maintenance tests” prioritizes reliability, optimization and improvement of safety procedures.

This study helps to determine the safest and most reliable corrective measures to improve the reliability of safety barriers. In addition, it also helps to protect people inside and outside the company from all kinds of major industrial accidents. Among the limitations of this study is that the cost of corrective actions is not taken into account.

Our contribution is to propose an integrated approach that uses interval type-2 fuzzy sets and AHP method and emergency event tree analysis to handle uncertainty in the failure probability assessment of emergency safety barriers. In addition, the integration of fault tree analysis and fuzzy ordered averaging aggregation helps to improve the reliability of the fire-fighting system and optimize the corrective actions that can improve the safety practices in liquefied petroleum gas storage tanks.

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H₂S storage tanks carried out in a heavy water plant, in order to characterize point type defects observed during earlier ultrasonic inspection and to ensure that these defects are not growing during hydrotesting of the tanks.

Using multiple AE sensors and AE source location methodology, the entire tank could be covered to detect and locate any dynamic sources of AE associated with local plastic deformation and/or growing discontinuities from any part of the tank during the hydrotest. For confirmation of the results obtained by AE, ultrasonic inspection on the tanks and on virgin plates from which the tanks were manufactured, were carried out.

The AE signals generated during first pressurisation are attributed to the micro yielding of the material of the tanks. A few scattered AE events were observed at a few locations during the hydrotesting of the tanks and these are due to structural and rubbing noise. During hold periods and repressurising cycle of the hydrotesting, no detectable AE events were observed and this confirmed the absence of any growing discontinuity in the tanks during the hydrotesting. Ultrasonic inspection on the tanks and on virgin plates confirmed that the point type defects detected are manufacturing defects and not formed during service life.

The combined results from AE and ultrasonic techniques confirmed the structural integrity of the tanks and ensured their healthiness for continued operation.

The paper brings out the use of AE and ultrasonic techniques for monitoring hydrotesting of storage tanks of a heavy water plant. The storage tanks where point type defect indications were reported during previous ultrasonic inspection and whether these defects are growing during hydrotesting of the tanks or not, were required to be known before the tanks are put in to further service. AE signals collected during pressurising and repressurising cycles of the hydrotest and subsequent inspection by ultrasonic confirmed the vessels to be free from growing defects during the hydrotest and provided baseline data for future inspection.

The aim of this study was to evaluate the performance of fuel flow processes in a network of eight gas stations, located in the mesoregion of Alto Paranaíba and Triângulo Mineiro.

Two multi-criteria decision support methods were applied, respectively, of a statistical and mathematical nature, namely, Principal Component Analysis (PCA) and Data Envelopment Analysis (DEA). The research method used was quantitative, with a brief complement of qualitative research, and descriptive in purpose, supported by the inductive method. The data collection stage took place with the support of interviews, with the application of a structured questionnaire, and non-probabilistic sampling, for convenience.

It was possible to verify that the gas station that stood out the most was station 2 (GS2), which achieved maximum efficiency, a fact that can be justified by the analysis resulting from the application of PCA, as for the product purchase variable (PP), the GS2 is the one that buys the most fuel, and is also the one with the largest storage capacity (C), and the highest volume of product sales (PS), which suggests signs of balance between supply and demand for this station, justifying its prominence.

The limitations of the study were related to the DEA technique, which requires a number of variables/indicators three times smaller than the number of DMUs considered, and the difficulty in obtaining financial data on the DMUs analyzed. Considering the security and anonymity of the gas station network, it was not possible to use this data.

The performance assessment of fuel flow processes carried out in this study promotes the efficient use of available resources as well as identifying efficient DMUs that represent benchmarks for improving management processes and performance of inefficient DMUs.

From a social perspective, this study promotes the improvement of the quality of flow processes and effective management of the fuel supply chain, ensuring the safe storage and transportation of fuels to customer supply. Performance management in this sector moves other sectors of the economy, since an efficient unit represents a balance between supply and demand, and consequently, boosts the regional economy, promoting economic growth of the population. Hiring qualified labor for this purpose also represents one of the implications of the study. From an environmental perspective, optimizing flow processes generates a reduction in greenhouse gas emissions and encourages the formulation of public policies aimed at consolidating sustainable practices.

Performance management applied to the context of the fuel supply chain is a relevant topic that has been little explored in scientific research, with a low level of information detail. This study using the inductive method allows the generalization and replication of this management pattern in other organizations in the sector in order to increase the efficiency of the fuel distribution system, with the perspective of maximizing outputs and reducing input consumption. In this aspect, the study introduces possibilities for advancement in social and environmental perspectives based on the effective management of fuel logistics.

This paper aims to present an underwater climbing robot for wiping off marine life from steel pipes (e.g. jackets of oil platforms). The self-adaption mechanism that consists of a passive roll joint and combined magnet adhesion units provides the robot with better mobility and stability.

Adhesion requirements are achieved by analyses of falling and slipping. The movement status on pipes is analyzed to design the passive roll joint. The optimized structure parameters of the combined magnet adhesion unit are achieved by simulations. An approximation method is established to simplify the simulations conditions, and the simulations are conducted in two steps to save time effectively.

The self-adaption mechanism has expected performance that the robot can travel on pipes in different directions with high mobility. Meanwhile, the robot can clean continuous region of underwater pipes’ surface of offshore platforms.

The proposed underwater robot is needed by offshore oil platforms as their jackets require to be cleaned periodically. Compared with traditional maintenance by divers, it is more efficient, economic and safety.

Due to the specific self-adaption mechanism, the robot has good mobility and stability in any directions on pipes with different diameters. The good performance of striping attachments from pipes makes the underwater robot be a novel solution to clean steel pipes.

The combination of rigidity, light weight, and thorough stabilization of the skins which is achieved by the use of a honeycomb core in sandwich structural components has made it a popular material, and its use is likely to increase. In the case of metal honey‐comb the main limitations are imposed by the difficulty of achieving a good bond between core and skin. To this end an adaptation of the now familiar Redux process has been announced by Aero Research Ltd., of Duxford, Cambridge, who first introduced the original process in 1942. The new variant involves the same materials as the normal process, but the powder is supplied in film form, in rolls, with a protective covering. In application the film is first consolidated on to the pickled skin sheet by heat and vacuum pressure. No priming of the metal surfaces is needed. Pressure can be applied by a rubber blanket, aluminium foil being used to separate it from the film, to prevent adhesion to the rubber. This operation is carried out at 145 deg. C. for ten minutes. The foil is then stripped off, and liquid Redux 120 applied by brush to the film and the honeycomb core. The liquid is dried for 30–60 minutes at 80 deg. C, and the component assembled. The whole is then cured at 145 deg. C. under vacuum pressure. Curing times vary with the proportions of the component, but are of the order of one hour.

The purpose of this paper is to discuss motion planning about crossing obstacles and welding trajectory for a new-model mobile obstacle-crossing welding robot system. The robot can cross the obstacle in this way that one of the three adhesion mobile parts is pulled off the ground in turn. An optimal obstacle-crossing approach needs to be studied to improve the welding efficiency.

According to the characteristics of this mobile welding robot, two methods for crossing obstacles are compared. A special method is used for obstacle-crossing and welding. The kinematic model is established. By the optimization method, the optimum parameters for crossing obstacles are calculated. The welding speed when the robot is crossing the obstacle is very important, so its value must be in a certain range. Finally, the tracks of the wheels when the robot is crossing the obstacle are analyzed in order to observe the obstacle-crossing process.

According to the analysis, the maximum speed of the vehicle in the obstacle-crossing is determined. When crossing the obstacle, the robot can do welding simultaneously. The welding speed cannot exceed a certain value. In the obstacle-crossing process, the tracks of the wheels can reflect the process. According to the obtained conclusion, the obstacle-crossing experiments are successfully completed, and the welding effect is good. The results can prove that the proposed method is feasible.

The speed of obstacle-crossing is not very large. It has some relationships with the lifting speed of the wheels, which is determined by the quality of drive motor. More efficient robot must be developed to meet the needs of industrial robot.

Based on the excellent obstacle-crossing and welding capabilities, the robot with the new mechanism has a widely applying prospect in the field of welding and inspecting large equipment.

The obstacle-crossing approach has certain innovation. The way that the robot can maintain continuous welding when crossing the obstacle is of a great significance.

Solar energy varies with time, intermittent; an accumulator unit is required to attach with collectors to collect energy for use when the sunshine is not available. This paper aims to design a system for storing the solar sensible heat thermal energy.

This paper presents the design and experimental evaluation of sensible heat thermal energy storage (TES) system for its energy storage performance by varying the air flow rate and packing material shape. Heat transfer fluid as air and solid concrete material of high density of different shapes were used for storage.

This paper presents the evaluation of data of number of experimental observations on the system. It was found that charging/discharging was based on the shape of the material and void fraction.

This paper provides the data for designing the TES, considering the concrete as storage material and shape of material for optimizing the system.

This paper aims to explore the dynamics of value co-creation in the context of health care logistics by focusing on the change in the value creation spheres of a logistics service provider and its customer organization.

The development of value co-creation between the two organizations was researched through a qualitative case study that focuses on a situation wherein the hospital’s central warehouse was moved to a more distant location. Data consist of the interviews and focus group discussions of both nursing staff and logistics managers before and after the change. The empirical results are reflected to service and value co-creation literature as well as to existing knowledge about health care logistics.

The new situation compelled the counterparts to plan more structured logistics service procedures, as there was no longer any possibility for nursing staff to pick up urgently needed items from the central warehouse. This strengthened the role of the joint value creation sphere and made it more visible during the change.

The study contributes to the evolving research on health care logistics and connects it to timely service value discussion. This paper proposes that as the physical distance of service facilities increases, the joint co-creation sphere, interestingly, gets widened during the change.

Managerially, the study provides implications for how to develop health-care material logistics to provide more value for both the logistics service providers and their customers.

Understanding value co-creation in health care logistics services supports care organizations in developing their processes toward better care for the patients. Thus, health care logistics research facilitates societies and health-care systems to reach their goals in terms of better service and lower costs.

This study presents an up-to-date example of value co-creation in the scarcely researched context of health care logistics.