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For allowable defect analyses, the fracture toughness of materials needs to be accurately predicted. In this regard, a lower fluctuation of fracture toughness can lead to reduction in safety and economic risks. Crack tip opening displacement (CTOD), which is the representative parameter for fracture toughness, can be measured by various methods, such as the δ 5 , the J-conversion method, the single clip gauge method, and the double clip gauge method. When calculating CTOD from test results, the principle of similar triangles, which adopts the plastic hinge model, is influenced by the rotation factor, r p . Therefore, in order to reduce the fluctuation of CTOD, the exact value of r p must be defined. This study investigates various methods to predict fracture toughness in metallic materials, and assess the pros and cons of each method. Moreover, the equation of r p is modified by using a double clip gauge in compact tension (CT) to reduce the fluctuation of CTOD. The r p value is derived from 0.55 to 0.68, using the double clip gauge method. Finite element analysis is used to derive the r p values, which range from 0.50 to 0.66, in order to verify the validity of the derived r p values. This ensures the validity of the r p value derived from the experiment. In addition, the fluctuation of CTOD, based on the modified equation of r p , is lower than that using the single clip gauge method, according to BS 7448. [ABSTRACT FROM AUTHOR]

Naval vessels face significant challenges owing to vibrations and shocks originating from diverse sources. Maintaining high levels of vibration and shock resistance in ship equipment is crucial to prevent damage and ensure proper functionality in demanding environments. This study experimentally and numerically investigates the shock characteristics of an electric switchboard on a naval ship using wire rope isolators (WRIs). Following the MIL-S-901D standard, impact tests were conducted using a test model. A simplified WRI model was constructed based on a previous study using the finite element method. The tests were performed in the vertical and 30° inclined orientations, and the experimental and simulation results were compared. Although an overall agreement was observed between the two, some inconsistencies were noted. These discrepancies were attributed to the inaccurate representation of the WRI. The dynamic stiffness of the WRI derived from the vibration tests conducted in this study may not be suitable for impact tests. Additionally, the modelled WRI in the simulation, as a 1D spring element with different support points, differed from the experimental setup, possibly causing localized effects that influenced the stress distribution. This study emphasizes the importance of refined WRI modelling for accurate shock simulations and offers insights into enhancing the shock resistance of naval ship equipment. [ABSTRACT FROM AUTHOR]

In 2010, the Department of Nuclear Engineering at Khalifa University of Science and Technology (NUCE) established the MSc degree in Nuclear Engineering. This program was established to support the United Arab Emirates (UAE) emerging civil nuclear energy program and produce graduate engineers capable of supporting the safe construction, operation, maintenance and eventual decommissioning of the UAE nuclear reactors. In order to enhance and consolidate classroom teaching, an overseas “Field Trip” module was integrated into the MSc curriculum in order to provide practical exercises, demonstrations and site visits. With respect to the consolidation of reactor physics teaching in particular, the field trips over the past 9 years have utilized mainly the AGN Zero Power reactor at Kyung Hee University (2012-2015) and the Breazeale TRIGA reactor at Penn State University (2017-2018). In both cases students gained “hands-on” supervised experience in classical reactor experiments, shielding measurements, health physics and radiological protection control, and radioanalytical measurement methods, such as neutron activation analysis. At Penn State University, the experiments were extended to surveillance measurements, taking advantage of the facilities specialized modules in nuclear security. This paper provides details of the arrangements made for the field trips and the learning outcomes these practical arrangements helped to satisfy meeting the overall degree outcomes. The case study will also illustrate where a nuclear energy newcomer State can take advantage of international collaborations without the need to invest in a national research reactor.