Introduction of Fracture
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The document discusses different modes of fracture in materials including ductile fracture, brittle fracture, and the transition between ductile and brittle. It examines fracture initiation and propagation at the microstructural level, including mechanisms such as void nucleation, growth, and coalescence in ductile materials. Factors that influence fracture such as grain structure, inclusions, and impurities are also explored.
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In view of Fatigue & Fracture Mechanics, the slides give a insight off the effects of the Creep and Fatigue Crack growth.
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原件一模一样【微信：bwp0011】《(Humboldt毕业证书)柏林大学毕业证学位证》【微信：bwp0011】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
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Null Bangalore | Pentesters Approach to AWS IAM
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
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- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
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Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
BRAIN TUMOR DETECTION for seminar ppt.pdf
BRAIN TUMOR DETECTION
AND CLASSIFICATION USING
ARTIFICIAL INTELLIGENCE
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Introduction of Fracture
- 1. Fracture: Microstructural Aspects Assignment Material Science and Enginering
- 3. Materials with Different Degrees of Brittleness
- 4. Ductile Fracture (a) Failure by shear (glide) in a pure metal. (Reprinted with permission from D. Broek, Elementary Engineering Fracture Mechanics, 3rd ed. (The Hague, Netherlands: Martinus Nijhoff, 1982), p. 33.) (b) A point fracture in a soft single-crystal sample of copper. (Courtesy of J. D. Embury.)
- 6. Crack Nucleation in HCP Metals a. Lattice rotation due to bend planes, b. Lattice rotation due to twinning, c. Crack nucleation in Zn due to lattice rotation caused by bend planes. (Courtesy of J.J. Gilman.)
- 7. Microcrack Formation at Twins Initiation of failure by microcrack formation in tungsten deformed at approximately 104 s−1 at room temperature. (a) Twin steps. (b) Twin steps and twin–twin intersection. (From T. Dümmer, J. C. LaSalvia, M. A. Meyers, and G. Ravichandran, Acta Mater., 46 (1998) 959.)
- 8. W-Type Cavitation w-type cavitation at a grain-boundary triple point.
- 9. r-Type Cavitation r-type cavitation at a grain boundary
- 10. Nucleation of a Cavity at a Second-Phase Particle Nucleation of a cavity at a second-phase particle in a ductile material. (Adapted with permission from B. R. Lawn and T. R. Wilshaw, Fracture of Brittle Solids (Cambridge: Cambridge University Press, 1975), p. 40.)
- 11. Dimple Fracture Dimple fracture resulting from the nucleation, growth, and coalescence of microcavities. SEM. Note the inclusion, which served as the microcavity nucleation site.
- 12. Cup and Cone Fracture
- 13. Cup and Cone Fracture
- 14. Ductile Fracture by Void Nucleation, Growth, and Coalescence
- 15. Ductile Fracture Progression: TEM In-situ Results
- 16. Ductility vs. Volume Fraction of Second Phase Ductility vs. volume fraction of second phase, f, for copper containing various second phase particles. The dashed line represents the prediction from the law of mixtures, assuming zero ductility for the second-phase particles. (From B. I. Edelson and W. J. Baldwin, Jr., Trans. ASM, 55 (1962) 230.)
- 17. Initiation of Void Growth by Dislocation Emission Prismatic Loops Shear Loops
- 18. Ductile-Brittle Transition Ductile–brittle transition in steel and the effect of loading rate.
- 19. Propagation of Transgranular Cleavage Propagation of transgranular cleavage. (Adapted from J. R. Low, in Madrid Colloquium on Deformation and Flow of Solids (Berlin: Springer-Verlag, 1956), p. 60.)
- 20. Cleavage Facets
- 21. Formation of Cleavage Steps
- 23. Intergranular Fracture in Steel
- 24. Sources of Flaws in Ceramics
- 25. Brittle Failure by Axial Splitting Compressive failure of a brittle material by axial splitting.