Investigation of linearity between mechanical properties of wood using graphical method

Some basic requirements are set for small clear specimen data to incorporate Malaysian timbers into equivalent European timber strength classes. In general, the correlation between structural and small clear specimen test results must be established for every timber group regardless of origin. This paper introduces a sort-plot technique for analysing the correlation of some mechanical properties of timber in selecting appropriate parametric model. Bending test was conducted on mixed species hardwoods for the determination of strength and stiffness values of both structural and small size specimens. The results showed that the sort-plot diagrams demonstrate an obvious linearity pattern between timber properties despite having poor regression values. The technique verified that properties of timber in structural and small size specimens correlated linearly

Elderly care monitoring system with IoT application

Falls among elderly can pose serious consequences such as injury or even fatal ones. Therefore, it is essential that fall are detected early and away to that is by using IoT platform. The authors have been developing a wearable device for elderly monitoring system utilizing accelerometer. The data from accelerometer is connected to an Internet-of-Things (IoT) platform called ThingSpeakTM. Based on IoT platform, elderly patients can be remotely monitored as long as the care providers have good internet access. The paper presents the experimental results of determining the sensitivity and specificity of the accelerometer used in the proposed system. This is the first step for developing an accurate data acquisition for monitoring purposes. Based on the experimental results, the average percentage for sensitivity obtained for this device is 73.3%, while the average for specificity obtained is 89.3%. Both sensitivity and specificity tests shows promising results which indicates that the device only has a fail rate of 26.7% and error rate of 10.7%

Occupational risk assessment: review of wooden scaffold board application in Malaysian oil and gas industry

Timber scaffold boards have been widely utilised in the offshore construction industry. However, technical specifications and inspection procedure for the application of scaffold boards from a wood material were inadequate. In the development of the standard requirements, evaluation of actual engineering practices could indicate the level of workplace safety. A study was conducted to identify risk and safety measures concerning the use of timber scaffold boards in construction. This article discusses on the occupational risks and ergonomics issues of the scaffolding application based on the physical and mechanical conditions of tropical timber scaffold boards extracted from offshore oil and gas rigs. The boards were exposed to a seasonal climate of East Coast monsoon of South China Sea between November and February. The scaffolding application extended up to 20 m directly above the ocean surface and some boards were completely immersed below the ocean surface particularly during elevated tidal waves. Some of the boards were installed as the on-deck platforms. Forty scaffold boards fabricated from tropical timber species were evaluated. Physical characteristics of the boards were described by natural and man-made factors. A three-point bending test was conducted to determine the maximum load capacity of each board and the mode of fracture was evaluated. Timber identification test was conducted to identify the groups of the timber being used. The microscopic observation confirmed the presence of hyphae which indicated the biological deterioration has happened in some of the boards. Occupational risks were summarised based on the results of the physical and mechanical assessments

Combined effect of neolamarckia cadamba leaves and electroporation method on hela cell anti- proliferation process

This study suggests that natural sources may become an important tool in treating cancer. Neolamarckia cadamba (NC) leaves also well-known as “Anthocephalus Cadamba”, is a precious plant in Ayurvedic medicine. HeLa cells are one of the examples of eukaryotic cells type. It is derived from human cervical cancer cells. This experiment is conducted in different concentrations of NC Leaves (1μg/ml, 5μg/ml, 10μg/ml, 20μg/ml, 30μg/ml, 40μg/ml, 50μg/ml, 60μg/ml, 70μg/ml, 80μg/ml, 90μg/ml and 100μg/ml) for 48 hours. This experiment’s result proves that the anti-cancer properties of the extract of NC leaves are by increasing the concentration of extract, the numbers of cell viability will decrease. For contribution, the process of NC leaves extract will be combined with the electroporation process to investigate the effect on HeLa cell. Electroporation parameters used for this study were (voltage 600v/cm, pulse duration 5ms, single pulse)

Development of a Mobile Robot with Camera-based Target Tracking and Obstacle Avoidance Systems

This work describes the preliminary design and development of a mobile robot called CREC (Camera-Based Mobile Robot for Elderly Care). The robot uses a low-cost HC-SR04 ultrasonic sensor to avoid obstacle, and a Pixy CMUcam5 camera as the vision-based sensor to track the target. This camera uses colour marker tag to follow and monitor the target. CREC uses an Arduino UNO microcontroller to fuse data conveyed by the ultrasonic sensor and camera so that the robot can follow the target and avoid obstacles simultaneously. In this work, the hardware design of CREC is described. Furthermore, preliminary experiments to characterize the ultrasonic sensor and Pixy camera are demonstrated to verify the usefulness of the selected sensors for the mobile robot

Development of a wrist rehabilitation device with android based game application

Traditional methods of rehabilitation that lacking excitement can contribute to demotivate patients in completing rehabilitation. Thus, interactive and interesting rehabilitation methods are essential to ensure stroke patients continue rehabilitation activity. This project proposes a wireless home based wrist rehabilitation device with an android-based game application (app). The patients will be able to do wrist therapy at home or anywhere with the rehabilitation device. The device is consists of an accelerometer that can measure acceleration in three dimensional space. It is developed in free wrist movement such as roll, pitch and yaw. The accelerometer data is processed by an Arduino Micro, and converted into mouse cursor movement that can be used in an android-based game app for rehabilitation. The game app called “BallGame” is being developed using the MIT App Inventor software. In this work, the hardware development of the rehabilitation device is presented. Furthermore, early development stages of the game app is described where the data from the rehabilitation device is successfully transmitted to the app via Bluetooth communication

Combined effect of Neolamarckia cdamba leaves and electroporation method on HeLa cell anti- proliferation process

This study suggests that natural sources may become an important tool in treating cancer. Neolamarckia cadamba (NC) leaves also well-known as “Anthocephalus Cadamba”, is a precious plant in Ayurvedic medicine. HeLa cells are one of the examples of eukaryotic cells type. It is derived from human cervical cancer cells. This experiment is conducted in different concentrations of NC Leaves (1μg/ml, 5μg/ml, 10μg/ml, 20μg/ml, 30μg/ml, 40μg/ml, 50μg/ml, 60μg/ml, 70μg/ml, 80μg/ml, 90μg/ml and 100μg/ml) for 48 hours. This experiment's result proves that the anti-cancer properties of the extract of NC leaves are by increasing the concentration of extract, the numbers of cell viability will decrease. For contribution, the process of NC leaves extract will be combined with the electroporation process to investigate the effect on HeLa cell. Electroporation parameters used for this study were (voltage 600v/cm, pulse duration 5ms, single pulse)

Strength assessment of structural size Malaysian timbers / Mohd Jamil Abdul Wahab

Existing strength data of Malaysian timbers are based on mechanical tests of small clear specimen. The formal mechanical properties assessment of timber in structural sizes has not been carried out for most tropical species, including Malaysian timbers. The present study is a groundwork testing on some selected commercial timbers to develop correlation factors between structural size and small clear specimens of timber in bending. A total of 120 planks of mixed species of Malaysian hardwoods were cut into standard sizes for structural size bending test as mentioned in EN 408:2003 and small clear specimen of 50 mm by 50 mm (2 inches by 2 inches) size according to ASTM D143 - 52. The ultimate results of MOR and MOE between the two testing methods were evaluated. Weak MOR correlation was observed between small clear and structural specimens. MOE relationship was shown to be consistent even for unconditioned and ungraded specimens. However, the risk of inaccurate deflection measurement is much higher for MOE in structural test. The developed correlation factors are then applicable for the data conversion of timbers in similar strength group where only small clear data exist. A robust statistical technique was introduced to group the Malaysian timbers into similar strength classes. The grouping is intended to simplify the conversion work of the existing strength data to equivalent structural size values

Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be achieved in artificial drying kilns such as conventional kiln, dehumidification kiln, solar kiln, radio frequency-vacuum, etc. The objective of this study was to evaluate the characteristics of 30 mm and 50 mm thick kekatong (Cynometra spp.) timber dried using kiln drying (KD) and radio frequency-vacuum drying (RFV) system. The investigation involved drying time, moisture content (MC) variations between and within boards, drying defects, shrinkage, and drying stress. Drying defects include checks (surface, end, and internal checks) and warping (bowing, cuping, spring, and twisting). The results showed that RFV drying time was reduced to 50% compared to the KD. RFV dried boards demonstrated a more uniform MC between and within boards. Shrinkage in width and thickness, as well as tangential/radial and volumetric shrinkages were substantially less in RFV boards. The amount of cupping, bowing and spring were very low and negligible in all drying runs. There was no twisting observed in all drying methods. The number of stress-free RFV board was higher than KD. With proper procedure, the RFV technology could be used for drying heavy hardwoods which are difficult to dry in conventional kilns due to excessive drying times and degradation

Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be achieved in artificial drying kilns such as conventional kiln, dehumidification kiln, solar kiln, radio frequency-vacuum, etc. The objective of this study was to evaluate the characteristics of 30 mm and 50 mm thick kekatong (Cynometra spp.) timber dried using kiln drying (KD) and radio frequency-vacuum drying (RFV) system. The investigation involved drying time, moisture content (MC) variations between and within boards, drying defects, shrinkage, and drying stress. Drying defects include checks (surface, end, and internal checks) and warping (bowing, cuping, spring, and twisting). The results showed that RFV drying time was reduced to 50% compared to the KD. RFV dried boards demonstrated a more uniform MC between and within boards. Shrinkage in width and thickness, as well as tangential/radial and volumetric shrinkages were substantially less in RFV boards. The amount of cupping, bowing and spring were very low and negligible in all drying runs. There was no twisting observed in all drying methods. The number of stress-free RFV board was higher than KD. With proper procedure, the RFV technology could be used for drying heavy hardwoods which are difficult to dry in conventional kilns due to excessive drying times and degradation