Behavior analysis of factors affecting safety management to reduce incidents in the pelletizing industry using the system dynamics approach

The purpose of this study was to analyze the behavior of effective factors on safety management to reduce incidents in the pelletizing industry using the system dynamics approach. Risk assessment for the Sechahon pelletizing plant was performed using the FMEA method. A total of 625 risks were identified in this complex of which 286 are high risk RPNs and need to be scrutinized. These risks were categorized according to their nature and consequences in five physical categories, exposure to dust, ergonomics, emergencies and psychosocial risks, so that they can be reviewed in detail. The results showed that decreasing the number of incidents in the risk reduction scenario would reduce the incidence earlier, and is initially more than other policies. The scenario of risk reduction is the best scenario in the short term. The technology improvement scenario shows an incremental growth trend, but the scenario of the current situation can better decrease the number of incidents. The human resource management and safety management scenario will initially be on an upward trend and will continue to decline. The human resource management and safety management scenario is a good way to reduce disasters in the long run. Keywords: safety management, system dynamics, incident reduction, pelletizing industry. DOI: 10.7176/IEL/10-1-06 Publication date: February 29th 202

Investigation on proximate composition, fatty acid profile and sensory evaluation of Nile (Oreochromis niloticus) and Hybrid Red Tilapia fillet farmed in brackish ground water of Bafgh, Yzad

The aim of this study was to determine proximate compositions and sensory evaluation of tilapia meat. For this purpose, farmed Nile tilapia and Red tilapia were collected from the Inland Saline Waters Aquaculture Research Center located in Bafgh, Yazd. Fish were transported to Aquatic Fish Processing Research Center. Fatty acid composition, protein, fat, moisture, ash and sensory evaluation in fish meat were analyzed. Results showed that the tilapia meat had 1.30–1.68% fat, 18.70-19.26 protein, 78-79% moisture and 1.34-1.8% ash. Twenty seven fatty acids were identified in the tilapia meat. Saturated fatty acids were found between 24.84–27.12%, mono-unsaturated fatty acids 36.14-39% and poly unsaturated fatty acids 32.38-38.12%. Amount of Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was calculated between 0.50-0.63% and between 6.12-6.19%, respectively. Results of sensory evaluation showed highest score for sensory evaluation parameters (color, odor, texture, test and flavors)

Operational leeway in the work situations: Do ergonomic risk assessment tools consider operational leeway for job analysis?

Our study shows that information on operational leeway is limited in the originator articles of the ergonomic risk assessment tools for prevention of musculoskeletal disorders (MSDs). The tools\u27 underlying theoretical models do not consider the indicators of operational leeway, and they cannot determine the sufficiency of the situational operational leeway in a work situation. Consequently, regulation of the activity, which ensures the performance goals and the individual\u27s health, has been overlooked. The lack of literature on the indicators of situational operational leeway is one of the reasons for this deficit. Defining the indicators for this concept would be an innovation in the approach of MSDs risk prevention. Developing empirically the concept of situational operational leeway in the risk assessment tools would help to progress in the current approach of MSDs prevention. This study therefore proposes the indicators of the situational operational leeway to increase the representativeness and reliability of the risk assessment tools for MSDs

Does Ergonomics Improve Product Quality and Reduce Costs? A Review Article

Competition is an ongoing challenge confronting industrial corporations, particularly automobile manufacturing. Striving to improve product quality and productivity, automotive industries have used different quality management approaches, such as reduced variability, total quality management, and lean management, over recent years. Furthermore, incorporating proactive ergonomics such as physical and organizational ergonomics and psychosocial factors into the structure of a company is considered to be a support for productivity and quality. Several studies have shown the effects of ergonomics on better quality. Application of both quality management approaches and ergonomics in an integrated manner in the manufacturing production system is emphasized because they are similar concepts with the same objectives, that is, to improve efficiency. In this study, a comprehensive review was undertaken and 25 studies were reviewed in order to define how integration of an ergonomic approach in the manufacturing production system can reduce defects and improve quality in the production process

Role of Steroid Therapy after Ischemic Stroke by N-Methyl-D-Aspartate Receptor Gene Regulation

Background: Stroke is the main cause of cerebrovascular disease mortality. Prolonged stimulation of N-methyl-D-aspartate (NMDA) receptor subtypes by the accumulation of glutamate neurotransmitter in the extracellular space after a stroke could activate cell death pathways. It is reported that progesterone provides different mechanisms of neuroprotection and could be considered as a candidate for stroke treatment. This study aimed to investigate progesterone impact on the expression of NMDA receptor subunits NR1, NR2(A and B), NR3 (A and B) after an experimental model of ischemic stroke which is followed by an in silico analysis. Methods: Progesterone was introduced subcutaneously after transient middle cerebral artery occlusion in male rats. After a period of reperfusion, a set of behavioral tests was performed to evaluate the postischemic neurological deficits. The 2,3,5-triphenyltetrazolium chloride staining method was done for quantification of infarct volume and gene expression analysis was performed in the penumbra region using reverse transcription polymerase chain reaction for NMDA receptor subunits. An AutoDock tool was employed to perform molecular docking analyses for evaluation of progesterone interaction with NMDA receptor. Results: Cerebral ischemia caused a significant downregulation in NR1, NR2A, NR2B and a profound upregulation of NR3B in cortical penumbraregion. Treatment with progesterone resu lted in upregulation of NR1, NR2A, and NR3B which could explain a possible the neuroprotection of steroids via binding to NMDA glutamate receptor. In addition, in silico analysis revealed that progesterone could strongly interact with NR1/NR2B and NR2A. Conclusion: The findings elucidate a new aspect of the neuroprotective mechanism of progesterone via NMDA receptors gene regulation. Keywords: Stroke NMDA receptor Progesterone Gene expressio

Global visualization and quantification of compressible vortex loops

The physics of compressible vortex loops generated due to the rolling up of the shear layer upon the diffraction of a shock wave from a shock tube is far from being understood, especially when shock-vortex interactions are involved. This is mainly due to the lack of global quantitative data available which characterizes the flow. The present study involves the usage of the PIV technique to characterize the velocity and vorticity of compressible vortex loops formed at incident shock Mach numbers ofM=1.54 and1.66. Another perk of the PIV technique over purely qualitative methods, which has been demonstrated in the current study, is that at the same time the results also provide a clear image of the various flow features. Techniques such as schlieren and shadowgraph rely on density gradients present in the flow and fail to capture regions of the flow influenced by the primary flow structure which would have relatively lower pressure and density. Various vortex loops, namely, square, elliptic and circular, were generated using different shape adaptors fitted to the end of the shock tube. The formation of a coaxial vortex loop with opposite circulation along with the generation of a third stronger vortex loop ahead of the primary with same circulation direction are of the interesting findings of the current study

Common-Ground-Type Single-Source High Step-Up Cascaded Multilevel Inverter for Transformerless PV Applications

The cascaded multilevel inverter (CMI) is one type of common inverter in industrial applications. This type of inverter can be synthesized either as a symmetric configuration with several identical H-bridge (HB) cells or as an asymmetric configuration with non-identical HB cells. In photovoltaic (PV) applications with the CMI, the PV modules can be used to replace the isolated dc sources; however, this brings inter-module leakage currents. To tackle the issue, the single-source CMI is preferred. Furthermore, in a grid-tied PV system, the main constraint is the capacitive leakage current. This problem can be addressed by providing a common ground, which is shared by PV modules and the ac grid. This paper thus proposes a topology that fulfills the mentioned requirements and thus, CMI is a promising inverter with wide-ranging industrial uses, such as PV applications. The proposed CMI topology also features high boosting capability, fault current limiting, and a transformerless configuration. To demonstrate the capabilities of this CMI, simulations and experimental results are provided

Development of a Biomechanical Method for Ergonomic Evaluation: Comparison with Observational Methods

A wide variety of observational methods have been developed to evaluate the ergonomic workloads in manufacturing. However, the precision and accuracy of these methods remain a subject of debate. The aims of this study were to develop biomechanical methods to evaluate ergonomic workloads and to compare them with observational methods. Two observational methods, i.e. SCANIA Ergonomic Standard (SES) and Rapid Upper Limb Assessment (RULA), were used to assess ergonomic workloads at two simulated workstations. They included four tasks such as tightening & loosening, attachment of tubes and strapping as well as other actions. Sensors were also used to measure biomechanical data (Inclinometers, Accelerometers, and Goniometers). Our findings showed that in assessment of some risk factors both RULA & SES were in agreement with the results of biomechanical methods. However, there was disagreement on neck and wrist postures. In conclusion, the biomechanical approach was more precise than observational methods, but some risk factors evaluated with observational methods were not measurable with the biomechanical techniques developed