Innovative honeycomb-based structures have been paid substantial attention in recent years due to their superb mechanical performances and specific functions. The presented study made acomprehensive overview on the development of the innovative honeycomb-based structures in the past two decades, including filled-type, embedded, tandem, hierarchical, auxetics with Negative Poisson's Ratio (NPR), etc. Mechanical performances of these structures were commented with advantages and disadvantages, related on their geometric configurations, mechanical performance and dynamic response, respectively. The challenges as well as future directions were also analyzed. The achievements provide significant guidelines in designing of new generation light-weight honeycomb-based structures.

Recent advances in novel metallic honeycomb structure

This paper reports the effects of annealing and age hardening heat treatments on the microstructural morphology and mechanical properties of 7075 Al alloy. The material was cast in the form of round cylindrical rods inside green sand mould from where some samples were rapidly cooled by early knockout and others gradually cooled to room temperature. From the samples that were gradually cooled some were annealed while others were age hardened. Both the as-cast in each category and heat treated samples were subjected to some mechanical tests and the morphology of the resulting microstructures were characterised by optical microscopy. From the results obtained there is formation of microsegregations of MgZn

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Effect of heat treatment on some mechanical properties of 7075 aluminium alloy

An unforeseen pandemic is facing the world caused by a corona virus known as SARS-CoV-2. Numerous measures are being put in place to try and reduce the spread of this deadly disease, with the most effective response to the outbreak being mass quarantines, a public health technique borrowed from the Middle Ages. The widely accepted main transmission mechanism is through droplet borne pathways. However, many researchers and studies are considering that this virus can also spread via the airborne route and remain for up to three hours in the air. This is leading to questions as to whether enough is being done regarding ventilation to reduce the risk of the spread of this or other diseases that may be air borne. Ventilation and air conditioning systems are the main focus when it comes to the transmission of such deadly pathogens and should be appropriately designed and operated. This paper reviews and critically evaluates the current ventilation strategies used in buildings to assess the state of the art and elaborates if there is room for further development, especially for high occupancy buildings, to reduce or eradicate the risk of pathogen transmission and adapt ventilation measures to new threats posed by pandemics.

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Review of ventilation strategies to reduce the risk of disease transmission in high occupancy buildings

Study of different heat exchange technologies influence on the performance of thermoelectric generators

Arbitrary Lagrangian–Eulerian finite element simulation and experimental investigation of wavy interfacial morphology during high velocity impact welding

The paper presents an experimental study on precipitation of aluminium alloy 6061-T6 to determine the effect of artificial ageing on the hardness of aluminium alloy 6061-T6. The precipitation hardening is a thermal treatment, which consists of a heat treatment, quenching and artificial ageing process. The experimental study is focused on artificial ageing upon which the temperature is varying between 175 o C to 420 o C at different period of time. The Vickers hardness test is to evaluate the hardness of aluminium alloy 6061-T6 before and after ageing process. The optimum ageing time and temperature is determined at the end of this experiment to obtain reduction in energy and total cost. The study leads to the conclusion that the optimum aged was achieved between 175 o C to 195 o C with 2 to 6 hours of ageing time. The contribution of short time ageing is comparable to that of longer ageing time from previous studies.

Effect of Hardness Test on Precipitation Hardening Aluminium Alloy 6061-T6

The degradation kinetics of poly(3-hydroxybutyrate) under non-aqueous and aqueous conditions

Heat spreading and heat transfer coefficient with fin heat sink

Seats are one of the most important components of vehicles and they are the place where professional driver spend most of their time. For example, according to Occupational Outlook Handbook by United State Department of Labor, the truck drivers frequently work 50 or more hours a week. The truck drivers sit while they are driving their 50 hours per week. Assuming four weeks vacation and one more for holidays, which is about 2350 hours driving time per year. Automotive seats, which are in contact with vehicle occupants, play an important role in improving the comfort and work environment of a driver and passengers. The improvement of automotive seating systems, particularly for the driver, has been the subject of intense interest for many years since a driver feels more fatigue than passengers. The paper describes a large variety of studies and up-to-date techniques developed for vehicle seats used by different type of transportation system such as cars, trucks, tractors, trains and aircrafts. The objective of this paper is to review the state of the art of vehicle seat design.

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Vehicle seat design : state of the art and recent development

The fire fighting is a risky work where the fire fighters need to face the fire hazards to save life and properties. Different equipments such as fire extinguisher, axes and cutting equipment are used to fight against fire. Fire fighting vehicle is being used to transport firefighters to the scene as well as transport the fire fighting equipments. The fire fighter is still facing the risk of fire hazard because they still need to go near to fire scene. To reduce the fire fighter risk during fire incident, a fire fighting mobile robot is designed. Fire fighting mobile robot is a remote controlled machine that replace fire fighter to perform fire fighting task. The application of fire fighting mobile robot is able to reduce the direct contact of fire fighter to the fire hazards. The paper reviews a variety of technologies and state-of-the-art technology of fire fighting mobile robot. The paper also describes the first Malaysian designed and built fire fighting mobile robot, namely, MyBOT2000.

Chee Fai Tan

Papers

Effect of Hardness Test on Precipitation Hardening Aluminium Alloy 6061-T6

The degradation kinetics of poly(3-hydroxybutyrate) under non-aqueous and aqueous conditions

Heat spreading and heat transfer coefficient with fin heat sink

Vehicle seat design : state of the art and recent development

Fire Fighting Mobile Robot: State of the Art and Recent Development