Preference for thinness in Singapore - A newly industrialised society

Singapore Medical Journal408502-507SIMJ

Voxel-based full-field eigenstrain reconstruction of residual stresses in additive manufacturing parts using height digital image correlation

The formation of residual stresses is inevitable during the additive manufacturing of metallic parts due to thermo-mechanicals effects, but the chaotic nature of printing processes makes it impossible to have a comprehensive understanding about the magnitude and distribution of these residuals. The voxel-based eigenstrain (inherent strain) reconstruction method is capable of the full-field reconstruction of residual stresses in discontinuous processing bodies at a scale that depends on the resolution of experimental data without using simplifying assumptions and regularisation functions. This advanced method firstly maps the distribution of eigenstrains and then quantifies corresponding residual stresses, residual elastic strains, and displacements by a cost-effective linear elastic computational framework. The reliability of this process solely depends on the quality of experimental data and the availability of computational power. The motivation behind this study is the use of the voxel-based eigenstrain reconstruction method for the full-field mapping of complex residual stress fields, that cannot be predicted by regularizing assumptions, in discontinuous processing additive manufacturing parts. The height Digital Image Correlation (hDIC) technique satisfied the need for high-quality experimental data by calculating triaxial displacements, corresponding to the elastic response of CM 247 LC powder bed fusion (PBF) additive manufacturing part after changes in the boundary conditions due to separation from the base, using optical profilometry measurements at a resolution adjusted in a way to reconstruct Type I residual stresses. Three components of displacements calculated by the hDIC were used to map the distribution of three components of eigenstrains for the reconstruction of six residual stress, six residual elastic strain and three displacement components that belong to the before and after separating from the base states. The reliability of calculations has been validated by monochromatic synchrotron X-ray beams in powder diffraction mode from the same surface of optical profilometry measurements and in transmission mode from the sampling volumes

Automated MRI Volumetric Analysis in Patients with Rasmussen Syndrome

Abstract The LIS educators need adequate and accurate knowledge of information to enhance effectiveness as well as productiveness of their teaching profession, most especially as a result of the emergence of ICT in library and information studies. In line with this, knowledge sharing practice for knowledge retention and growth was investigated among the LIS educators in Akanu Ibiam Federal Polytechnic Ebonyi State. A simple random sampling technique was used to select 32 respondents who represented the sample size for the study. Data was obtained through the use of a structured questionnaire. Frequency counts, percentages, means, standard deviations and PPMC were used for data analysis. Findings revealed that 68.8% of the respondents were male and 31.3% female, 59.4% were Senior Lecturers and 65.6% were between ages 40 to 49 years. Majority (87.5%) of the respondents shared professional knowledge and exchange research knowledge and out-put, while 78.2% shared knowledge for career development. On the other hand, 100%, 90.6%, and 59.4% were not sharing knowledge relating to family issues, experiences, methods of teaching and ICT related issues. However, 100% of the respondents realised the importance of knowledge sharing in their department as they shared knowledge during departmental meetings, seminars, workshops, interpersonal interaction and also encouraged their students to share knowledge among themselves. Sharing knowledge with colleagues improved knowledge retention of the respondents (93.8%), and Knowledge sharing built their assimilation skills (78.2%). Furthermore, 87.5% of the respondents were able to apply the knowledge gained from interaction with their colleagues to their professional routine. This built the growth of their information acquisition, confidence and ability to withstand educational related activities, including the respondents’ productivities in teaching and research output (68.7%). Disinterest to get engaged in debate sessions about the specialized fields of Library and Information Science (68.8%) and lacked of cooperation among the faculty members, dissimilarity of the level of knowledge and experience between the faculty members (62.5%) is affecting their knowledge-sharing practice. PPMC revealed that knowledge sharing significantly (