7 research outputs found

    A Review of MRI Acute Ischemic Stroke Lesion Segmentation

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    Immediate treatment of a stroke can minimize long-term effects and even help reduce death risk. In the ischemic stroke cases, there are two zones of injury which are ischemic core and ischemic penumbra zone. The ischemic penumbra indicates the part that is located around the infarct core that is at risk of developing a brain infarction. Recently, various segmentation methods of infarct lesion from the MRI input images were developed and these methods gave a high accuracy in the extraction and detection of the infarct core. However, only some limited works have been reported to isolate the penumbra tissues and infarct core separately. The challenges exist in ischemic core identification are traditional approach prone to error, time-consuming and tedious for medical expert which could delay the treatment. In this paper, we study and analyse the segmentation algorithms for brain MRI ischemic of different categories. The focus of the review is mainly on the segmentation algorithms of infarct core with penumbra and infarct core only. We highlight the advantages and limitations alongside the discussion of the capabilities of these segmentation algorithms and its key challenges. The paper also devised a generic structure for automated stroke lesion segmentation. The performance of these algorithms was investigated by comparing different parameters of the surveyed algorithms. In addition, a new structure of the segmentation process for segmentation of penumbra is proposed by considering the challenges remains. The best accuracy for segmentation of infarct core and penumbra tissues is 82.1% whereas 99.1% for segmentation infarct core only. Meanwhile, the shortest average computational time recorded was 3.42 seconds for segmenting 10 slices of MR images. This paper presents an inclusive analysis of the discussed papers based on different categories of the segmentation algorithm. The proposed structure is important to enable a more robust and accurate assessment in clinical practice. This could be an opportunity for the medical and engineering sector to work together in designing a complete end-to-end automatic framework in detecting stroke lesion and penumbra

    Performance of CFRP retrofitted two way RC slabs with modified epoxy

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    &nbsp;The research is focused in improving the performance of two-way reinforced concrete slabs retrofitted with CFRP using modified epoxy. The work concluded the advantages of the new epoxy over the conventional epoxy, the structural behaviour of two way reinforced concrete slabs strengthened with CFRP was improved.<br /

    A Review on Strength and Durability Properties of Wooden Ash Based Concrete

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    The partial replacement of cement in concrete with other building materials has come to light because of research on industrial waste and sustainable building practices. Concrete is made more affordable by using such components, and it also helps to ease disposal worries. Ash made by burning wood and other wood products is one example of such a substance. Many researchers focused on the utilization of wooden ash (WA) as a construction material. However, information is scattered, and no one can easily judge the impact of WA on concrete properties which restrict its use. Therefore, a details review is required which collect the past and current progress on WA as a construction material. relevant information. This review aims to collect all the relevant information including the general back of WA, physical and chemical aspects of WA, the impact of WA on concrete fresh properties, strength properties, and durability aspects in addition to microstructure analysis. The results indicate the WA decreased the slump and increased the setting time. Strength and durability properties improved with the substitution of WA due to pozzolanic reaction and micro-filling effects. However, the optimum dose is important. Different research recommends different optimum doses depending on source mix design etc. However, the majority of researcher suggests a 10% optimum substitution of WA. The review also concludes that, although WA has the potential to be used as a concrete ingredient but less researchers focused on WA as compared to other waste materials such as fly ash and silica fume etc

    Basalt Fibers Reinforced Concrete: Strength and Failure Modes

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    The low tensile capacity of concrete often results in brittle failure without any warning. One way to cope with this issue is to add fibers and essentially improve the tensile strength (TS) behavior of concrete and offset its undesirable brittle failure. In recent investigations, basalt fibers (BFs), as compared to a variety of other kinds of fiber, have attracted the attention of researchers. In that respect, BFs exhibit several benefits, such as excellent elastic properties, great strength, high elastic modulus, higher thermal stability, and decent chemical stability. Although many researchers have reported that BFs can be embedded in concrete to improve the tensile capacity, a more profound understanding of its contribution is still needed. However, the information is scattered and it is difficult for the reader to identify the benefits of BFs. Therefore, a detailed assessment is essential to summarize all relevant information and provide an easy path for the reader. This review (part â… ) summarizes all the relevant information, including flow properties, strength properties, and failure modes. Results reveal that BFs can greatly enhance the strength properties and change the brittle nature of concrete to one of ductility. However, it unfavorably impacts the flowability of concrete. Furthermore, the optimal proportion is shown to be important as a higher dose can adversely affect the strength of concrete, due to a deficiency of flowability. The typical range of the ideal incorporation of BFs varies from 0.5 to 1.5%. Finally, the review also indicates the research gap for future research studies that must be cautiously explored before being used in the real world

    Feasibility Study on Concrete Made with Substitution of Quarry Dust: A Review

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    Concrete mechanical properties could be improved through adding different materials at the mixing stage. Quarry dust (QD) is the waste produced by manufactured sand machines and comprise approximately 30&ndash;40% of the total quantity of QD generated. When it dries, it transforms into a fine dust that poses a tremendous hazard to the environment by contaminating the soil and water and seriously endangering human health. QD utilization in concrete is one of the best options. Though a lot of scholars focus on imitation of QD in concrete, knowledge is scattered, and a detailed review is required. This review collects the information regarding QD-based concrete, including fresh properties, strength, durability, and microstructure analysis. The results indicate that QD is suitable for concrete to a certain extent, but higher percentages adversely affect properties of concrete due to absence of fluidity. The review also indicates that up to 40&ndash;50% substitution of QD as a fine aggregate can be utilized in concrete with no harmful effects on strength and durability. Furthermore, although QD possesses cementitious properties and can be used as cement substitute to some extent, less research has explored this area

    Feasibility Study on Concrete Made with Substitution of Quarry Dust: A Review

    No full text
    Concrete mechanical properties could be improved through adding different materials at the mixing stage. Quarry dust (QD) is the waste produced by manufactured sand machines and comprise approximately 30–40% of the total quantity of QD generated. When it dries, it transforms into a fine dust that poses a tremendous hazard to the environment by contaminating the soil and water and seriously endangering human health. QD utilization in concrete is one of the best options. Though a lot of scholars focus on imitation of QD in concrete, knowledge is scattered, and a detailed review is required. This review collects the information regarding QD-based concrete, including fresh properties, strength, durability, and microstructure analysis. The results indicate that QD is suitable for concrete to a certain extent, but higher percentages adversely affect properties of concrete due to absence of fluidity. The review also indicates that up to 40–50% substitution of QD as a fine aggregate can be utilized in concrete with no harmful effects on strength and durability. Furthermore, although QD possesses cementitious properties and can be used as cement substitute to some extent, less research has explored this area

    A Review of MRI Acute Ischemic Stroke Lesion Segmentation

    Get PDF
    Immediate treatment of a stroke can minimize long-term effects and even help reduce death risk. In the ischemic stroke cases, there are two zones of injury which are ischemic core and ischemic penumbra zone. The ischemic penumbra indicates the part that is located around the infarct core that is at risk of developing a brain infarction. Recently, various segmentation methods of infarct lesion from the MRI input images were developed and these methods gave a high accuracy in the extraction and detection of the infarct core. However, only some limited works have been reported to isolate the penumbra tissues and infarct core separately. The challenges exist in ischemic core identification are traditional approach prone to error, time-consuming and tedious for medical expert which could delay the treatment. In this paper, we study and analyse the segmentation algorithms for brain MRI ischemic of different categories. The focus of the review is mainly on the segmentation algorithms of infarct core with penumbra and infarct core only. We highlight the advantages and limitations alongside the discussion of the capabilities of these segmentation algorithms and its key challenges. The paper also devised a generic structure for automated stroke lesion segmentation. The performance of these algorithms was investigated by comparing different parameters of the surveyed algorithms. In addition, a new structure of the segmentation process for segmentation of penumbra is proposed by considering the challenges remains. The best accuracy for segmentation of infarct core and penumbra tissues is 82.1% whereas 99.1% for segmentation infarct core only. Meanwhile, the shortest average computational time recorded was 3.42 seconds for segmenting 10 slices of MR images. This paper presents an inclusive analysis of the discussed papers based on different categories of the segmentation algorithm. The proposed structure is important to enable a more robust and accurate assessment in clinical practice. This could be an opportunity for the medical and engineering sector to work together in designing a complete end-to-end automatic framework in detecting stroke lesion and penumbra
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