Newcomers’ Barriers. . . Is That All? An Analysis of Mentors’ and Newcomers’ Barriers in OSS Projects

Newcomers’ seamless onboarding is important for open collaboration communities, particularly those that leverage outsiders’ contributions to remain sustainable. Nevertheless, previous work shows that OSS newcomers often face several barriers to contribute, which lead them to lose motivation and even give up on contributing. A well-known way to help newcomers overcome initial contribution barriers is mentoring. This strategy has proven effective in offline and online communities, and to some extent has been employed in OSS projects. Studying mentors’ perspectives on the barriers that newcomers face play a vital role in improving onboarding processes; yet, OSS mentors face their own barriers, which hinder the effectiveness of the strategy. Since little is known about the barriers mentors face, in this paper, we investigate the barriers that affect mentors and their newcomer mentees. We interviewed mentors from OSS projects and qualitatively analyzed their answers. We found 44 barriers: 19 that affect mentors; and 34 that affect newcomers (9 affect both newcomers and mentors). Interestingly, most of the barriers we identified (66%) have a social nature. Additionally, we identified 10 strategies that mentors indicated to potentially alleviate some of the barriers. Since gender-related challenges emerged in our analysis, we conducted nine follow-up structured interviews to further explore this perspective. The contributions of this paper include: identifying the barriers mentors face; bringing the unique perspective of mentors on barriers faced by newcomers; unveiling strategies that can be used by mentors to support newcomers; and investigating gender-specific challenges in OSS mentorship. Mentors, newcomers, online communities, and educators can leverage this knowledge to foster new contributors to OSS projects.     

Preparation of Ag-Al₂O₃ nano structures by combustion method and investigation of photocatalytic activity

In this research, Ag-Al₂O₃ nanostructures have been prepared via combustion synthesis and ammonium acetate and urea have been applied as fuels. The prepared Ag-Al₂O₃ nanostructures were characterized by DTA, XRD, SEM, TEM, and BET spectroscopy. The effect of different ratios of silver to alumina and fuel percentage on morphology and particle size of prepared products were investigated. The results showed that using ammonium acetate fuel led to the production of Ag-γ-Al₂O₃ nanocompounds, while using urea produced Ag-α-Al₂O₃. Also, the photocatalytic activity of Ag-Al₂O₃ nanostructures for Congo red degradation was evaluated by UV-Vis diffuse reflectance spectroscopy. The photocatalytic activity of Ag-Al₂O₃ was examined under UV-Vis irradiation and showed significant photocatalytic efficiency.     

Crystallization and photo‐curing kinetics of biodegradable poly(butylene succinate‐co‐butylene fumarate) short‐segmented block copolyester

Short‐segmented block copolymers of poly(butylene succinate‐co‐butylene fumarate) were synthesized and their crystallinity and crosslinking behavior were investigated. ¹H NMR was used to characterize the microstructure and composition of the copolyesters. Molecular weight determination was performed using gel permeation chromatography. Based on the DSC results all copolyesters were crystalline and the degree of crystallinity of the copolymers did not change with butylene fumarate mole fraction due to co‐crystallization of the butylene succinate and butylene fumarate groups. Crosslinked copolyesters showed a lower crystallization rate and degree of crystallinity while the crystallization temperature shifted to higher temperatures compared with uncrosslinked copolyesters due to the formation of nucleating agents by crosslinkages. Photo‐DSC was used to investigate the crosslinking kinetics for UV‐initiated photo‐curing. Three kinetics parameters including the rate constant (k) and the orders of the initiation and propagation reactions (m and n, respectively) were determined for the quenched and unquenched copolymers. © 2016 Society of Chemical Industry     

A two-dimensional finite element recursion relation for the transport equation using nine-diagonal solvers

Abstract

A Galerkin-based finite element recursion relation is used to solve the heat transport equation in two-dimensions. The finite element method (FEM) is a powerful technique that is commonly used for solving complex engineering problems. However, the implementation of the FEM in multi-dimensional problems can be computationally expensive. A finite element recursion algorithm based on bilinear triangular, bilinear quadrilateral and quadratic Lagrangian approximations are employed to discretize the 2-D advection-diffusion equation. This algorithm is an extension of the 1-D Chapeau (linear element) technique, which employed a tridiagonal recursion expression common to the classical central finite-difference approach. The global matrix is nine-diagonal (for 2-D) and is solved using a modified strongly implicit procedure and a left-to-right sweep method.