The effect of tensile strength and surface roughness by varying oxygen level in 3D printer chamber

The part produced by the fused filament fabrication (FFF) 3D printer in terms of surface roughness, tensile strength, and dimensional accuracy depends mainly on the printing parameters and the environmental printing conditions. In this paper, nitrogen gas had been allowed to flow inside the 3D printer chamber to maintain an inert environment and to remove the rate of concentration oxygen inside the chamber. This paper is devoted to studying the influence of layer thickness and surface roughness on the mechanical properties of 3D-printed parts. Tensile and surface roughness tests were performed on samples of three different layer thicknesses (0.1mm, 0.2mm, and 0.3mm) using an Acrylonitrile Butadiene Styrene (ABS) in (FFF) 3D printing method. Therefore, the results explain the oxygen ambient is 10.295 (MPa) at the 0.1mm layer thickness for the tensile test, which is weaker than nitrogen ambient of 11.767 (MPa). The scanning electron microscope (SEM) observed a strong bonding with microstructure (fewer deficiencies and voids) for 0% oxygen, compared to 10% and 20% with the large void area

Accuracy assessment of TanDEM-X DEM and global geopotential models for geoid modeling in the southern region of peninsular Malaysia

In modeling of geoid model, global digital elevation models (GDEMs) and global geopotential models (GGMs) involve in most part of the geoid computation process. Any errors in GDEMs and GGMs will introduce errors directly in geoid computation. Therefore, this study aims to evaluate the six recent GGMs and new digital elevation model from TanDEM-X, as well as the previously available GDEMs, SRTM GDEMs, over the southern region of Peninsular Malaysia. The evaluation of GDEMs has been performed with the use of high-precision Global Navigation Satellite System (GNSS) and EGM96 as vertical reference consisting of 277 stations. Meanwhile, the evaluation of GGMs is carried out using sixty-two (62) collocated GPS/leveling benchmarks (BMs). Based on the statistical analysis, it is shown that the improvement of DEM from TanDEM-X data is compared to the previously available DEMs, SRTM GDEMs. DEM from TanDEM-X of 30-m arc resolution is much better than TanDEM-X of 12-m arc resolution, as well as SRTM 30m and 90m. Comparison of GGMs with GNSS leveling shows that geoid height from GOCO05c fits well with the local geoid model

MASJID LAMA BATU 6, BATU 6 JALAN GOMBAK, 53100 KUALA LUMPUR, SELANGOR MALAYSIA

The study of Masjid Lama Batu 6 in Gombak takes us back to the early Minang establishments in the area, along with the importance of the Masjid in a community and how it is designed to function as a place of worship, gathering and religious or educational activities. Although built in 1931, talk of an older masjid along the Sungai Gombak still remains to this day. The Masjid, however, is now adjacent to the main road Jalan Gombak and has modern additions to it and plans for future renovations continue. However, many elements, such as the roof structure and the timber column ‘tiang’ or soko guru, have still been kept from the original masjid. The study of Masjid Lama Batu 6 comprises the building’s and its physical site’s evolution throughout history, the surrounding culture of the people as well as its neighbourhood context. The Masjid, to this day, essentially functions as a core part of the community, holding religious as well as social requirements of Muslims, with the space for prayer as well as an adjoining hall to multi-function as an extended prayer space or to provide an educational and/or event space. The first part of the report conveys the analytical studies of Masjid Lama Batu 6, which include: history, chronology, architectural influences, the site context of the masjid, the culture and social aspects along with the migration of the first society with the new society of Batu 6. The second part of the report is a compilation of measured drawings of Masjid Lama Batu 6 Gombak. The report further evaluates the structure of the masjid, how the role of culture and religion in shaping the architecture of masjids in the region and how other factors such as climate, geography and technology can affect a building design. Ultimately, the studies are made to benefit the generations to come on the local masjid and their unique heritage