Morphology of Street Vegetation along Pedestrian Walkways in Kuala Lumpur City Centre

The Kuala Lumpur City Hall (KLCH) has planted 100,000 trees along the main streets of the city centre through the National Economic Transformation Programme to make the city more liveable. This paper studies the reasons for its different establishments, and it determines the social and physical benefits to the pedestrian walkways through a further investigation regarding the morphological parameters used by the Landscape Department of KLCH. The outcomes indicated that the street vegetation morphology implemented is mainly to improve the social and physical condition of the pedestrian walkways, especially the safety of the pedestrians due to snatching and reckless crossings.Keywords: Street Vegetation; City Centre; Main Street; Pedestrian WalkwayseISSN: 2398-4287 © 2019. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.DOI: https://doi.org/10.21834/e-bpj.v4i12.162

Effect Of Post Processing Parameters Andcompression Behavior On FDM 3D-Printed ABS Lattice-Structures

There is a growing development in lattice structure due to fundamental interest of the industries in producing parts with higher performance albeit with a low energy and cost consumption. Lattice structure is a periodic cellular structure which can serve the purpose of achieving lightweight parts with good mechanical properties. The complexity of manufacturing numerous types of lattice structures can be overcome by additive manufacturing (AM) process which offers better reliability and relatively simple procedure as compared to normal manufacturing. For the past decade, there are many studies on the lattice structure fabrication by AM. However, from literature, it is found that not many studies reported about the investigation on lattice structure by non-metallic, especially the ABS polymer. The use of ABS polymer to produce lattice structure serves as an added value for lightweight applications due to the lightweight characteristics of the ABS itself. The fused deposition modeling (FDM) 3D printed process of lattice structure is rarely reported in previous studies, hence it is difficult to confidently understand the behaviour of produced lattice structure by using combinations of FDM parameters. On top of that, there is limited information regarding the relationships between the pre-set parameters of CubePro’s mid- range FDM printed lattice structure with its mechanical properties. Therefore, this study characterized and examined the manufacturability of lattice structure geometry that was produced by FDM. The effect of process parameters of mid-range FDM 3D printer on the geometry of ABS lattice-structure were then evaluated. Later, the relationships between mechanical properties of ABS FDM 3D printed lattice structure with its geometry were derived by using experimental approach to justify the material as lightweight material. The CubePro 3D printer machine was utilized to fabricate the BCC lattice structure cube specimens with dimension of 20 x 20 x 20 mm3 with strut’s diameter sizes of 1.2 mm, 1.4 mm and 1.6 mm. Optical microscopy was used to characterize the printed lattice structures cube specimens. Theoretical approach was performed to compare the results with previous studies. The lattice structures specimens were tested with quasi-static compression loading to examine its mechanical properties and then the relations between process-properties of FDM 3D printed lattice-structure were derived. The significant process parameters that influenced the mechanical performance as well as the geometrical properties for this particular FDM printer machine was found to be the layer thickness. The best mechanical performance of lattice structure was observed for that produced with 200 µm layer thickness as it gave a good agreement between the theoretical approach and experimental data analysis. With respect to the deformation behavior of the lattice structure in this study, the material is found to be more suitable in energy absorption applications such as in car engine hood or arm parts of the drone due to the bending dominated behavior when subjected to loading

Characterizing Passively Q-switched Fiber Laser in LiDAR Application

A LiDAR system consists of a Q-switched fiber laser that emits light pulses to measure the distance from the target. We have experimentally demonstrated a passively Q-switched erbium-doped fiber laser (EDFL) by employing graphene saturable absorber (SA). The SA was prepared by dipping a polyvinyl alcohol (PVA) thin film into the graphene solution. Once the SA was fabricated, it can be placed in the cavity to perform pulses and it is operating at 1558.92 nm. The shortest pulse received is 3.9 µs and generated at the repetition rate of 115 kHz. The pulses are stable between pump powers of 59.6mW and 127.1 mW. At the maximum pump power value of 127.1 mW, The laser cavity produced pulses with a 1.4mW output power and a 1.1nJ pulse energy

Characterizing Passively Q-switched Fiber Laser in LiDAR Application

A LiDAR system consists of a Q-switched fiber laser that emits light pulses to measure the distance from the target. We have experimentally demonstrated a passively Q-switched erbium-doped fiber laser (EDFL) by employing graphene saturable absorber (SA). The SA was prepared by dipping a polyvinyl alcohol (PVA) thin film into the graphene solution. Once the SA was fabricated, it can be placed in the cavity to perform pulses and it is operating at 1558.92 nm. The shortest pulse received is 3.9 µs and generated at the repetition rate of 115 kHz. The pulses are stable between pump powers of 59.6mW and 127.1 mW. At the maximum pump power value of 127.1 mW, The laser cavity produced pulses with a 1.4mW output power and a 1.1nJ pulse energy

Failure Behaviour Of 3D-Printed ABS Lattice Structure Under Compression

Lattice structure is a lightweight material that can be produced using the cutting edge additive layer manufacturing process or also known as 3D printing. Lattice structure material is a periodic cellular structure material that can be utilized in various applications especially as core material in sandwich structure configuration, where the ultimate aim is to be a lightweight material with load bearing capability. Researches are yet to be done to fully understand the behavior of lattice structure materials under several loading conditions such as tensile, bending and compression. The objective of this paper is to discuss the behavior of acrylonitrile-butadiene-styrene (ABS) lattice structure material that was produced using the layer by layer manufacturing, subjected to compressive load. Lattice structure specimens with dimension 20x20x20 mm3 were designed with body centered cubic (BCC) unit cells for three sets of strut diameter size. The specimens were produced using fused deposition modelling (FDM) Cubepro 3D printer, with varying default parameters of layer thickness, print strength and print pattern. All specimens were subjected to compressive load until densification stage and the stress-strain curves of the material were plotted. The compressed specimens were observed under an optical digital microscope and a common failure behavior of 3D-printed ABS lattice structure material was highlighted. It was shown that the failure of compressed lattice structure was initiated at joint node areas due to bending tensile stress. It can be concluded that this polymer material showed hybrid between stretch and bending-dominated characteristics. This is a good indicator for lightweight material with load absorbing capability. An understanding in the failure behavior of ABS lattice structure material is enriching the knowledge on this material under stress-strain condition

Integrated optics europium aluminum polymer optical waveguide with graded index circular core

A Europium Aluminum Benzyl Methacrylate (Eu-Al/BzMA) integrated optical waveguide with 50 μm graded-index multimode circular core is fabricated by applying the Mosquito method for the potential application of optical interconnect. The parabolic index profile of the waveguide core is measured to confirm the profile exhibited by the waveguide. A preliminary experiment of the signal transmission is performed at 26 Gb/s to evaluate its capability in high dense and speed optical interconnections. According to the results, the waveguide successfully demonstrated free bit-error-rate through 5 cm waveguide transmission

Static And Dynamic Analysis Of FDM Printed Lattice Structures For Sustainable Lightweight Material Application

This study investigated the effect of strut diameter size of fused deposition modelling (FDM) printed lattice structure on compressive performance and its relation to dynamic behaviour of the lattice structure using vibration analysis.The lattice structure samples were fabricated using FDM 3D printing/additive manufacturing (AM) technique with three sizes of strut diameters:1.2 mm,1.4 mm and 1.6 mm.Findings from compression test showed that increased in size of strut diameter would increase the compressive strength performance as well as better energy absorptions.Similar increased trend was shown in the vibration analysis as the strut diameter size increased.This study provides information that lattice structure is suitable for use in dynamic load bearing applications

Investigation On Process-Properties Relationship With Load-Bearing Performance Of Lattice-Structured Cellular Material For Lightweight Applications

Lattice structure is a periodic cellular structure which can become lightweight materials with good mechanical properties. This study characterized and examined the manufacturability of lattice structure geometry that was produced by FDM CubePro 3D-printer. The effect of process parameters on ABS lattice-structure's geometry were evaluated and their relationships were derived by using experimental approach. Dynamic behaviour of the material was explored for a better understanding of the material in real applications. The BCC lattice structure specimens were subjected with quasi-static compression and dynamic vibration loadings. Significant process parameter that influenced mechanical performance and geometrical properties for the FDM printer machine was found to be the layer thickness at 200 pm. Vibration test results show that the material's natural frequency was greatly affected by strut diameter sizes due to increase in stiffness as the strut diameter increases. The natural frequency values increase as induced damage location became farthest from clamped edge. With respect to both compression deformation and vibration behaviours of the lattice structure in this study, the material is found to be more suitable in energy absorption applications such as in car engine hood or arm parts of drone due to its bending dominated behaviour when subjected to loading