Deep tillage tool optimization by means of finite element method: Case study for a subsoiler tine

Technologies and computer capacity currently available allow us to employ design software and numerical methods to solve complicated problems in very wide disciplines of engineering. It is also important for researches in agriculture. This study focused on obtaining optimum geometry parameters of a subsoiler tine by using computer aided engineering (CAE) applications. A field experiment was conducted to determine draft force of the subsoiler. The results from the experimental study were used in the finite element analysis (FEA) to simulate stress distributions on the subsoiler tine. The maximum equivalent stress of 432.49 MPa was obtained in the FEA. Visual investigations and FEA results showed that according to the tine’s material yield stress point of 355 MPa, plastic deformation was evident. Based on the FEA results, an optimization study was undertaken to obtain optimum geometry parameters without the occurrence of plastic deformation. According to the optimization study results, the optimum parameters of the tine geometry and maximum equivalent stress of 346.61 MPa were obtained. In addition to this, the total mass of the tine was reduced by about 0.367 kg

A Potential Research Area Under Shadow In Engineering:Agricultural Machinery Design and Manufacturing

As a branch of the global machinery industry, the agricultural (farm) machinery design and manufacturing or agricultural engineering industry has become one of the most important industries to be supported and focussed on in the era of hunger threats foreseen in the World’s future. In order to produce sufficient volumes of food from current limited agricultural land, well-designed machinery and high technology-supported mechanisation of the agricultural production processes is a vital necessity. However, although novel improvements are observed in this area, they are very limited. There is a lack of implementation of advanced engineering design and manufacturing technologies in this industry, therefore agricultural engineering could be considered a potential engineering research area with this in mind. This study aims to highlight the potential, gaps, sector specific challenges and limitations of the agricultural engineering research area at a macro level. Under consideration of the sector-specific indicators, the study revealed a major result: there is an insufficient level of sector-specific research on implementation strategies for up-to-date design and manufacturing technologies

Design and structural optimisation of a tractor mounted telescopic boom crane

In this research, an application algorithm, which can be used in computer-aided design/engineering (CAD/CAE) and structural optimisation-based design studies of agricultural machineries, is introduced. This developed algorithm has been put in practice in a case study for a tractor mounted telescopic boom crane. The algorithm consists of both numerical and experimental methods and it includes material testing, three-dimensional (3D) computer-aided design and finite-element method (FEM)-based analysis procedures, structural optimisation strategy, physical prototyping, physical testing and design validation procedures. Following the visual and physical validation procedures carried out in the case study, the crane’s physical prototype was manufactured and the optimised design was approved for ongoing production. The study provides a unique CAD/CAE and experimentally driven total design pathway for similar products, which contributes to further research into the utilisation of engineering simulation technology for agricultural machinery design, analysis and related manufacturing subjects

Design and Additive Manufacturing of a Medical Face Shield for Healthcare Workers Battling Coronavirus (COVID-19)

During the coronavirus disease-19 pandemic, the demand for specific medical equipment such as personal protective equipment has rapidly exceeded the available supply around the world. Specifically, simple medical equipment such as medical gloves, aprons, goggles, surgery masks, and medical face shields have become highly in demand in the health-care sector in the face of this rapidly developing pandemic. This difficult period strengthens the social solidarity to an extent parallel to the escalation of this pandemic. Education and government institutions, commercial and noncommercial organizations and individual homemakers have produced specific medical equipment by means of additive manufacturing (AM) technology, which is the fastest way to create a product, providing their support for urgent demands within the health-care services. Medical face shields have become a popular item to produce, and many design variations and prototypes have been forthcoming. Although AM technology can be used to produce several types of noncommercial equipment, this rapid manufacturing approach is limited by its longer production time as compared to conventional serial/mass production and the high demand. However, most of the individual designer/maker-based face shields are designed with little appreciation of clinical needs and nonergonomic. They also lack of professional product design and are not designed according to AM (Design for AM [DfAM]) principles. Consequently, the production time of up to 4 – 5 h for some products of these designs is needed. Therefore, a lighter, more ergonomic, single frame medical face shield without extra components to assemble would be useful, especially for individual designers/makers and noncommercial producers to increase productivity in a shorter timeframe. In this study, a medical face shield that is competitively lighter, relatively more ergonomic, easy to use, and can be assembled without extra components (such as elastic bands, softening materials, and clips) was designed. The face shield was produced by AM with a relatively shorter production time. Subsequently, finite element analysis-based structural design verification was performed, and a three-dimensional (3D) prototype was produced by an original equipment manufacturer 3D printer (Fused Deposition Modeling). This study demonstrated that an original face shield design with <10 g material usage per single frame was produced in under 45 min of fabrication time. This research also provides a useful product DfAM of simple medical equipment such as face shields through advanced engineering design, simulation, and AM applications as an essential approach to battling coronavirus-like viral pandemics

Structural Strength Analysis of a Rotary Drum Mower in Transportation Position

A rotary drum mower is a tractor-mounted harvester used for harvesting green fodder plants in agricultural fields. During transportation, it experiences significant dynamic road reaction forces that can cause deformation and functional failures. This study focuses on analysing the deformation behaviour of the machine during transportation to test the machine’s failure condition. To conduct the strength analysis, a total work cycle scenario reflecting actual load conditions and design challenges was created. Experimental strain-gauge-based stress analysis and advanced computer-aided engineering (CAE) simulation methods were employed. The study successfully conducted experimental stress analysis, 3D solid modelling, and validated finite element analysis (FEA). A comparison between experimental and simulation results showed an average relative difference of 24.25% with a maximum absolute difference of approximately 5 MPa. No functional failure issues were observed during physical experiments. The study also revealed that the mean dynamic loading value, when compared to the static linkage position, was calculated as 3.65 ± 0.40. Overall, this research provides a valuable approach for future studies on complex stress and deformation evaluations of agricultural machinery and equipment

Determining the instantaneous bruising pattern in a sample potato tuber subjected to pendulum bob impact through finite element analysis

Potato bruising resulting from mechanical impact during production operations including harvest and postharvest is a significant concern within the potato production sector, leading to consumer complaints and economic losses. The detection of instantaneous internal bruising poses a particular challenge as it can progress over time during storage or transportation, making it difficult to identify immediately after external impact. This study aims to investigate the progression of bruising and accurately represent the instantaneous dynamic deformation behavior of potato tubers under four pendulum bob impact cases (pendulum arm angles of 30°, 45°, 60°, and 90°). To analyze the dynamic impact deformation characteristics of the tubers, solid modeling based on a reverse engineering approach and explicit dynamic engineering simulations were employed. The simulation results yielded valuable numerical data and visual representation of the deformation progression. The loading conditions considered in this study indicated that the maximum stress values, reaching 0.818 MPa at a pendulum arm angle of 90°, remained below the bio-yield stress point of the tuber flesh (1.05 MPa) determined through experimental compression tests. Therefore, it was concluded that the impact did not cause permanent deformation (i.e., permanent bruising) in the tuber. However, the numerical analysis clearly demonstrated the sequence of stress occurrences, which is a key contributing factor to potential permanent bruising. In this regard, the bruising energy threshold of 318.314 mJ (R2: 0.96) was extrapolated. The numerical findings presented in this study can aid in evaluating the susceptibility of tuber samples to bruising. By employing nonlinear explicit dynamics simulations, this research contributes to the advancement of understanding complex deformation and bruising in solid agricultural products. Moreover, the application of these techniques holds significant industrial implications for enhancing the handling and transportation of agricultural produce. Practical applications: This research aims to tackle the challenge of accurately representing the immediate internal bruising pattern in potato tubers resulting from mechanical impact. Conventional methods, such as physical or analytical expressions, may not fully capture the distribution of bruising experienced by the tubers. To overcome this limitation, an engineering simulation approach is proposed to provide a more precise depiction of the instantaneous bruising pattern. By advancing the understanding of complex deformation and bruising in solid agricultural products, this research contributes to improving the efficiency and quality of agricultural production in the industry. Additionally, this study offers a step-by-step guide on how to conduct these simulations effectively

Reverse engineering approach for precise measurement of the physical attributes related to the geometric features of agricultural products

The characteristics related to the physical properties of agricultural products can be considered when designing and sizing machinery systems/equipment used in agricultural production. Agricultural products as biological/organic materials have several unique characteristics, which set them apart from conventional engineering materials such as steel and plastic based materials, in the context of inner structure and product geometry/shape. Agricultural materials have heterogeneous inner structures and irregular shapes cultured by nature. Most especially, the irregular shape of most agricultural products complicates their physical and engineering analysis. Therefore, precise description of the irregular product geometry/shape is significant for any related analyses used in both product quality evaluation and design of agricultural machinery systems. This study describes a reverse engineering application procedure for precise description of the physical attributes related to geometric features (size, shape, volume etc.) of the agricultural products under consideration. In the study, a three-dimensional (3D) laser scanner has been utilised and 3D digital model data of the selected sample agricultural product (Pecan) processed in the virtual environment through 3D scanner software and 3D parametric solid modelling design software has been collected. After 3D solid models were created, some of the physical attributes related to geometric features of the agricultural products were measured precisely and realistic virtual 3D computer aided design (CAD) data was provided for deeper rheological investigation such as structural deformation, fluid dynamics (flow) and heat transfer analyses of the products by means of computer aided engineering (CAE) techniques. Finally, a comparative deformation simulation case study was concluded. This study contributes to further research into the development of agricultural machinery and equipment through the utilisation of reverse engineering and CAD tools

Gastric intramucosal pH is stable during titration of positive end-expiratory pressure to improve oxygenation in acute respiratory distress syndrome

BACKGROUND: Optimal positive end-expiratory pressure (PEEP) is an important component of adequate mechanical ventilation in acute lung injury and acute respiratory distress syndrome (ARDS). In the present study we tested the effect on gastric intramucosal pH of incremental increases in PEEP level (i.e. PEEP titration) to improve oxygenation in ARDS. Seventeen consecutive patients with ARDS, as defined by consensus criteria, were included in this clinical, prospective study. All patients were haemodynamically stable, and were not receiving vasopressors. From an initial level of 5 cmH(2)O, PEEP was titrated at 2 cmH(2)O increments until the partial arterial oxygen tension was 300 mmHg or greater, peak airway pressure was 45 cmH(2)O or greater, or mean arterial blood pressure decreased by 20% or more of the baseline value. Optimal PEEP was defined as the level of PEEP that achieved the best oxygenation. The maximum PEEP was the highest PEEP level reached during titration in each patient. RESULTS: Gastric mucosal pH was measured using gastric tonometry at all levels of PEEP. The thermodilution technique was used for measurement of cardiac index. Gastric mucosal pH was similar at baseline and at optimal PEEP levels, but it was slightly reduced at maximum PEEP. Cardiac index and oxygen delivery remained stable at all PEEP levels. CONCLUSION: Incremental titration of PEEP based on improvement in oxygenation does not decrease gastric intramucosal perfusion when cardiac output is preserved in patients with ARDS

Strength-based Design Analysis of a Para-Plow Tillage Tool

In this research, experimental field tests and an advanced computer aided design and engineering (CAD and CAE) based application algorithm was developed and tested. The algorithm was put into practice through a case study on the strength-based structural design analysis of a Para-Plow tillage tool. Para-Plow is an effective tractor attached tillage tool utilised as an alternative to the conventional deep tillage tools used in agricultural tillage operations. During heavy tillage operations, the Para-Plow experiences highly dynamic soil reaction forces which may cause undesired deformations and functional failures on its structural elements. Here, prediction of the deformation behaviour of the tool structure during tillage operation in order to describe optimum structural design parameters for the tool elements and produce a functionally durable tool become an important issue. In the field experiments, draft force and strain-gauge based measurements on the tool were carried out simultaneously. Subsequently, Finite Element Method based stress analysis (FEA) were employed in order to simulate deformation behaviour of the tool under consideration of the maximum loading (worst-case scenario) conditions tested in the field. In the field experiments, average and maximum resultant draft forces were measured as 33,514 N and 51,716 N respectively. The FEA revealed that the maximum deformation value of the tool was 9.768 mm and the maximum stress values impart a change on the most critical structural elements of between 50 and 150 MPa under a worst-case loading scenario. Additionally, a validation study revealed that minimum and maximum relative differences for the equivalent stress values between experimental and simulation results were 5.17% and 30.19% respectively. This indicated that the results obtained from both the experimental and simulation are reasonably in union and there were no signs of plastic deformation on the Para-Plow elements (according to the material yield point) under pre-defined loading conditions and a structural optimisation on some of the structural elements may also be possible. This research provides a useful strategy for informing further research on complicated stress and deformation analyses of related agricultural equipment and machinery through experimental and advanced CAE techniques

Transcriptome analysis of differentially expressed circRNAs miRNAs and mRNAs during the challenge of coccidiosis

Avian coccidiosis is a common enzootic disease caused by infection of Eimeria species parasites. It causes huge economic losses in the global poultry industry. Current control using anticoccidial drugs or vaccination is limited due to drug resistance and the relatively high cost of vaccines. Improving host genetic resistance to Eimeria species is considered an effective strategy for improved control of coccidiosis. Circular RNAs (circRNAs) have been found to function as biomarkers or diagnoses of various kinds of diseases. The molecular biological functions of circRNAs, miRNAs, and mRNAs related to Sasso chicken have not yet been described during Eimeria species challenge. In this study, RNA-seq was used to profile the expression pattern of circRNAs, miRNAs, and mRNAs in spleens from Eimeria tenella-infected and non-infected commercial dual-purpose Sasso T445 breed chickens. Results showed a total of 40 differentially expressed circRNAs (DEcircRNAs), 31 differentially expressed miRNAs (DEmiRNAs), and 820 differentially expressed genes (DEmRNAs) between infected and non-infected chickens. Regulatory networks were constructed between differentially expressed circRNAs, miRNAs, and mRNAs to offer insights into the interaction mechanisms between chickens and Eimeria spp. Functional validation of a significantly differentially expressed circRNA, circMGAT5, revealed that circMGAT5 could sponge miR-132c-5p to promote the expression of the miR-132c-5p target gene monocyte to macrophage differentiation-associated (MMD) during the infection of E. tenella sporozoites or LPS stimulation. Pathologically, knockdown of circMGAT5 significantly upregulated the expression of macrophage surface markers and the macrophage activation marker, F4/80 and MHC-II, which indicated that circMGAT5 might inhibit the activation of macrophage. miR-132c-5p markedly facilitated the expression of F4/80 and MHC-II while circMGAT5 could attenuate the increase of F4/80 and MHC-II induced by miR-132c-5p, indicating that circMGAT5 exhibited function through the circMGAT5-miR-132c-5p-MMD axis. Together, our results indicate that circRNAs exhibit their resistance or susceptive roles during E. tenella infection. Among these, circMGAT5 may inhibit the activation of macrophages through the circMGAT5-miR-132c-5p-MMD axis to participate in the immune response induced by Eimeria infection