Leaf micro-morphological characteristics of selected Vatica species (Dipterocarpaceae) from Kubah National Park, Sarawak

Genus Vatica L. is one of the largest groups in the family Dipterocarpaceae with 71 species have been botanically described, distributed from India, Sri Lanka to Myanmar, Indochina, Sumatra, Borneo and the Philippines. Borneo with 35 species has the largest representative. In Sarawak, 32 species have been recorded, occurring especially in mixed and upper dipterocarp forests and also non-saline habitats from sea level up to about 1,800 m altitude. Kubah National Park is among the richest site for genus Vatica in Sarawak with 11 species recorded. The Vatica species are distinguished from other genera of Dipterocarpaceae by the absence of looped intra-marginal nerves on leaf, winged fruits encloses less than half of the nut, glabrous anthers and stout style. However, in term of inter species within its genus, Vatica is the most difficult dipterocarp to be identified, which explains why this common genus so poorly known. This study was conducted to examine leaves characteristics particularly its micro morphology to differentiate some selected Vatica species from Kubah National Park. Leaves samples were observed via Scanning Electronic Microscope (SEM). The characteristics and indumentums were compared between each species and noted. Results show that leaf micro morphology characteristics are significantly useful to differentiate the species level and intra-specific level

A revision of genus Vatica L. (Dipterocarpaceae) in Borneo I:Taxa in Sabah and Sarawak

A taxonomic revision of the genus Vatica L. (Dipterocarpaceae) in Borneo focusing on taxa Sabah and Sarawak is presented herein. A total of 46 taxa from 40 species is recognised and grouped into three sections. The sections are sect. Vatica 17 taxa (12 species), sect. Sunaptea 22 taxa (21 species), sect. Pachynocarpa with four species, and Vatica pentandra which has five stamens is not placed in any section due to lack of information of the fruit calyx characteristics. Full descriptions of species are excluded as they are presented elsewhere

3D Numerical modelling on the thermal performance of reinforced concrete encased wide-flanged steel column

This paper presents the development and verification of a three-dimensional (3D) numerical modelling to predict the thermal performance of reinforced concrete encased wideflanged steel (RCEWFS) column. The numerical model was developed using finite element software, ABAQUS. Then, the verified model was used to determine the suitable value for heat transfer conductance, time step and mesh size that provide the most reliable prediction against the experimental results. The parametric studies were also conducted to study the effect of rising time of fire exposure, section size, and flange width of I-section on the thermal performance of the RCEWFS column. From this study, it can be concluded that the predictions by the 3D numerical model are reliable and accurate. The study on the contour of the model shows that the thermal behaviour of concrete is non-linear

A training monitoring system for cyclist based on wireless sensor networks

This paper presents a training monitoring system for cyclist that is based on the technology of wireless sensor networks (WSNs). A stable and reliable wireless cyclist monitoring system is vital to establish a smart and efficient sports management program. A training monitoring system has been developed and tested in a real cyclist training environment in a velodrome. The system is designed is such a way that the packet loss rate is minimum. Using TelG mote as the basis, customized sensor nodes that function as a forwarder node and the relay nodes are developed to form the WSN. This WSN is linked to the cloud network on the Internet. The cloud network is then established and end users application for data accessing is designed. Several experiments have been conducted in a real scenario in a velodrome to measure the reliability of the system architecture. It is shown from the experiments that the proposed system is reliable even when the cyclist is moving at a high speed. The packet loss is less than 2% which does not give a huge impact to the data transmission

Titanium dioxide-based picoseconds pulsed fiber laser performances comparison in the 1.5-micron region

We demonstrated and compared picoseconds pulsed fiber lasers based on Titanium dioxide based saturable absorbers (SAs); 20 cm long Titanium dioxide-doped fiber (TiO2DF) and Titanium dioxide PVA film (TiO2PF) in the 1.5-micron region. The laser cavity utilized 2.4 m long Erbium-doped fiber (EDF) as the gain medium. A self-starting pulsed laser with a consistent repetition rate of ∼1 MHz emerged stably with the incorporation of TiO2 based SAs. The TiO2DF SA produced 9.74 ps pulsed laser at a central wavelength of 1553 nm within a pump power range of 106-142 mW. The fiber SA promoted slightly higher slope efficiency and maximum pulse energy of 13.17 and 8.56 nJ, respectively in comparison with the film SA. On the other hand, the TiO2PF SA generated stable 3.89 ps pulsed laser at an operating wavelength of 1560 nm within 86-142 mW pump power range. The film SA also produced slightly greater maximum output power of 12.17 mW and maximum peak power of 3.43 kW, respectively at the maximum pump power. The results confirmed that both TiO2 SAs can be good alternative pulse modulator in the 1.5-micron region

Adaptive FEC error control scheme for wireless video transmission

Transmission errors have detrimental impact on video quality in wireless network. Hence, this requires highly efficient error correction scheme to significantly improve the quality of the media content. Deploying error correction technique alone would not strategically eradicate the problem unless some adaptation mechanism has been included in order to make efficient decision while adding more redundant information base on the channel condition. Adapting with channel condition can significantly enhance the network performance and video quality as well. In this paper, we paper presents an approach using forward error correction and cross layer mechanism which dynamically adapts with the channel condition to recover the loss packets in order to enhance the perceived video quality. The scheme has been developed and tested on NS-2 simulator and it shows more dramatic improvement in video quality

Iot-based intelligent irrigation management and monitoring system using arduino

Plants, flowers and crops are living things around us that makes our earth more productive and beautiful. In order to growth healthy, they need water, light and nutrition from the soil in order to effect cleaning air naturally and produce oxygen to the world. Therefore, a technology that manage to brilliantly control plants watering rate according to its soil moisture and user requirement is proposed in this paper. The developed system included an Internet of Things (IoT) in Wireless Sensor Network (WSN) environment where it manages and monitors the irrigation system either manually or automatically, depending on the user requirement. This proposed system applied Arduino technology and NRF24L01 as the microprocessor and transceiver for the communication channel, respectively. Smart agriculture and smart lifestyle can be developed by implementing this technology for the future work. It will save the budget for hiring employees and prevent from water wastage in daily necessities