Comparative study on Leaf disease identification using Yolo v4 and Yolo v7 algorithm

Agriculture is the primary occupation of nearly all nations that feed the world's population. The population growth and rising demand for food require farmers to increase food production to meet the requirements. On the other hand, farming is not regarded as a lucrative occupation, as farmers incur significant losses due to pests and diseases that reduce the quality and quantity of farm produce. Consequently, predicting plant diseases using modern technologies will aid producers in making well-informed decisions early on. This study employs and compares the results of two important computer vision algorithms, YOLOv4 and YOLOv7, for classifying leaf diseases from images of leaves from various plant species. The models are trained with images of individual leaves captured in various environments, imparting resilience and adaptability. Both models annotate and predict leaf diseases with high confidence for each class. Other classification metrics, such as Precision, F1-score, Mean Average Precision, and recall, also demonstrate competitive performance. However, YOLOv7 performs better because its flexible labeling mechanism dynamically learns the class labels. In addition, the work can be expanded to utilize recommendation strategies to predict the extent of injury.Wang Xinming (Dr, professor, Ph.D., Department of Mechanical and Manufacturing Engineering), Tang Sai Hong (Dr professor, Ph.D., Department of Mechanical and Manufacturing Engineering), Mohd Khairol Anuar b. Mohd Ariffin (Dr, professor, Ph.D., Department of Mechanical and Manufacturing Engineering), Mohd Idris Shah b. Ismail (Dr, professor, Ph.D., Department of Mechanical and Manufacturing Engineering)Includes bibliographical references

Generic framework for conceptual design using concurrent engineering strategy. A case study: advanced material application - product development of metal matrix composite component

One of the keys to success for product competition in the market depends on the effectiveness of its product development. This article presents a generic framework of product development which focuses on the conceptual design. The framework is developed with concurrent engineering strategy where it takes into account the product life cycle considerations within the early phases of the conceptual design. The proposed framework starts from product investigation, product specification and conceptual design. Implementation of the framework is illustrated on a case study of metal matrix composite brake disc rotor design, where there is an avenue for conceptual research since the progress of metal matrix composite utilisation in the automotive industry is limited due to their high cost in comparison with conventional alloy. The possible outcome for product investigation, product specification and conceptual design of metal matrix composite brake disc rotor are presented as part of the selection of best conceptual design. Moreover, the proposed framework is an aid to help engineers and designers to make an effective and systematic product development through a sound conceptual design decision from possible product concept alternatives

New technique for conceptual selection of manufacturing process and material, case study: metal matrix composite component

This article introduces a new technique involving concurrent engineering (CE) strategy and analytical network process (ANP) technique to form a ranking methodology as a part of the conceptual design selection (CS). The proposed method is referred as concurrent network (CN). The objective of this study is to simultaneously consider of all features of product elements by implementing CE strategy. Furthermore, CN enables interdependence and interrelationship analysis between product elements by application of ANP. In this study, CN is utilized for a conceptual design of metal matrix composite (MMC) component. The results show that by using CN, all important product parameters can be considered simultaneously during the CDS and the importance weights of manufacturing process parameters and material parameters which are related to MMC component performance are attained

Recent developments of kenaf fibre reinforced thermoset composites: review

Kenaf fibres are recently upcoming reinforcement material to be used in composites. This is due to its low density, commercially viability, no health risk, high specific strength and modulus and renewability. It can also be cultivated in a variety of soil and is easily cultivable in some countries. Although traditionally it has been used for products such as rope, twine, bagging and rugs, recently, interests have grown for uses in other applications such as fibre reinforced composites. This paper reviews the recent developments in the use of kenaf fibre as a reinforcement material in thermoset composites. This paper also discusses the multiple types of kenaf fibres itself that are currently available in the market. The processes of kenaf cultivation and pretreatment have also been reviewed. The properties of various kenaf reinforced thermoset polymer composites, interface between kenaf fibre and matrix, and multitude of current manufacturing processes have also been discussed and presented. Recommendations for further research and development have also been given in this paper

Process parameters for cylindrical deep drawing components

Sheet metal forming is one of the most important manufacturing processes in today’s industries, either to produce semi-finished or finished products. The demand for rapid, low-cost die fabrication and modification technology is greater than ever in sheet metal forming industry. Therefore, a great need for the development of both theoretical and experimental engineering methods which enables the problems to be tackled effectively; this is necessary to reduce production cost and to reduce the lead time between design and production. Due to recent development in numerical method technology, finite-element analysis has become one of the important tools in predicting the result of product deformation. With the intention to study the product failure which is the thinning effect, an experimental method has been developed to monitor the metal flow behaviour during the process. With this experiment, the actual product has been drawn with different draw depths, punch and die corner radii on mild steel and aluminium materials. Finally, the product wall thickness and diameter have been measured and data gained were interpreted into graph to visualise the influences of the process parameters such as draw depth, punch and die corner radius on the thinning effect. The results would give tool maker and tool designer guidance for selecting the best punch and die radius size in order to minimise the thinning effect on the drawn product

Computational analysis of the groove effect to reduce the cavitation in ball valves

Cavitation is a phenomenon that frequently creates fear within the engineering industry as the violent and critical attacks by cavitation can cause a lot of damage to ball valves. This paper is presented to reduce the risk of cavitation attack due to dramatic pressure drop and to demonstrate the ball valve performance. The ball valve with grooves was simulated and compared with current method under same boundary conditions as with existing experimental of ball valves. The proposed device can be operated in aircraft to isolate the fuel system and the engine fuel system after engine shutdown or emergency. The proposed implementation has successfully shown to eliminate the dramatic pressure drop effects to the ball valve. In the case study, at a closing angle of 40° at which violent cavitation occurs, the ball valve showed increasing cavitation intensity performance to 0.3 or 30%. The average performance of the cavitation index for all cases also increased to 24%

An experimental validation and optimisation tool path strategy for thin walled structure

This work was carried out with the aim to optimise the tool path by simulating the removal of material in a finite element environment which is controlled by a genetic algorithm (GA). To simulate the physical removal of material during machining, a finite element model was designed to represent a thin walled workpiece. The target was to develop models which mimic the actual cutting process using the finite element method (FEM), to validate the developed tool path strategy algorithm with the actual machining process and to programme the developed algorithm into the software. The workpiece was to be modelled using the CAD (ABAQUS CAE) software to create a basic geometry co-ordinate system which could then be used to create the finite element method and necessary requirement by ABAQUS, such as the boundary condition, the material type, and the element type

The effect of bentonite clay on green compression strength for tailing sands from old tin mines in Perak state, Malaysia for making green sand casting mould

Clay has an important role in making green sand casting mould beside water. Clay acts as binders, holding the sand grains together. Water is needed to activate the clay bond. Without the addition of water on clay, no strength would be achieved on sand mould, as the sand and clay would be just two dry materials. Bentonite clay was used in this study. Adequate clay content with suitable moisture in moulding sand is important for optimum strength and casting quality. Too little or too much clay will not give proper strength. Green compression strength is one of the mechanical properties to be considered for making green sand casting mould. The green compression strength of foundry sand is the maximum compressive strength that a mixture is capable of sustaining when prepared, rammed and tested according to standard procedure. For this study, test is conducted according to Foundry Sand Testing Equipment Operating Instructions from Ridsdale and Dietert. Result from this study indicates that tailing sand has potential for making green sand casting mould in term of green compression strength. Other factors that must be considered are permeability and shatter index

Green compression strength of tin mine tailing sand for green sand casting mould

Tailing sand is the residue mineral from tin extraction that contains between 94% and 99.5% silica, which can be used as moulding sand. It is found in abundance in the Kinta Valley in the state of Perak, Malaysia. Adequate water content and clay in moulding sand are important factors for better strength and casting quality of products made from tailing sand. Samples of tailing sand were investigated according to the American Foundrymen Society (AFS) standard. Cylindrical test pieces of Ø50 mm×50 mm in height from various sand-water ratios were compacted by applying three ramming blows of 6666g each using a Ridsdale-Dietert metric standard rammer. The specimens were tested for green compression strength using a Ridsdale-Dietert universal sand strength machine. Before the tests were conducted, moisture content of the tailing sand was measured using a moisture analyser. A mixture bonded with 8% clay possesses higher green compression strength compared to samples bonded with 4% clay. The results also show that in order to achieve maximum green compression strength, the optimum allowable moisture content for mixtures bonded with 8% clay is ranged between 3.75 and 6.5% and for mixtures bonded with 4% clay is 3-5.5%

Effect of moisture content on the permeability of tailing sand samples gathered from ex tin mines in Perak state Malaysia

Tailing sand is one of the residue minerals obtained after tin extraction. It contains silica in between 94% and 99.5% and available in abundance at the Kinta Valley, Perak State, Malaysia. Permeability is one of the important molding sand properties and considered much in the sand casting mold preparation. This molding sand property plays a vital role in the sand casting process and helps to remove the gases during the casting processing. In this research work, samples of tailing sands were gathered from four identified ex tin mines located at the Perak State, Malaysia. They were investigated by the standard sand testing procedures prescribed by the American Foundrymen Society (AFS). Sand specimens of size Ø50 mm×50 mm in height from various sand–water ratios bonded with 4% and 8% clay were compacted on applying three ramming blows of 6666 g each by using a Ridsdale-Dietert metric standard rammer. The specimens were tested for permeability number with the aid of a Ridsdale-Dietert permeability meter. Before the tests were conducted, the moisture content was measured by using a moisture analyzer. The results were compared with the properties of the molding sand samples collected from RCS Manufacturing Sdn. Bhd., the company supplying sand to the Proton Casting unit car manufacturing company. The molding sand sample sample bonded with 8% clay was found to have maximum permeability with an optimum allowable moisture content range of 3.5-6.0% and for the sand mixture bonded with 4% clay at 3.0-3.5% moisture