Advanced Anaerobic Suspended Growth Closed Bioreactor (ASGCB) for the Production of Biomethane Gas

Keywords: Anaerobic Degradation Process, Palm Oil Mill Effluent, Biogas Production, Methane Gas, Renewable Energy, Volatile Fatty Acids, 16S rDNA Bacterial Identification.

iTACS - Interactive Training & Assessment For Cataract Surgery

iTACS is a virtual reality cataract surgery simulator, providing an interactive training and assessment platform for ophthalmologists to conduct their surgical practice and rehearsal via computer and a pair of force feedback haptic devices, where surgical performance is evaluated along the training. The cataract surgery simulator is capable of providing selection on every parts of eye anatomy including cornea, iris, lens, sclera and muscle for medical practitioners to study and observe around the inner part of the human eye which can’t be approached on live patients.

Various types of virtual surgical instruments are available in the simulator for users to choose when performing particular surgical procedures. Since two haptic devices are equipped for the surgical simulators, surgeons and medical trainees are able to switch the tools between both hands by referring to the graphical user interface (GUI) that is created in the platform. Visual feedback such as tissue deformation and force reaction movements of human eyeball are implemented into the simulator along with haptic feedback that gives tactile sensation when collision is detected during the simulation. Users are able to sharpen their skills on specific surgical procedures by referring to the performance evaluation system embedded in the simulator. Concerns in phacoemulsification cataract surgery such as position of corneal incision and damage on posterior capsule during phacoemulsification are embedded in the proposed surgical simulator to improve the awareness of ophthalmologists in avoiding surgical trauma and retinal detachment. Besides that, graphical surgical guidance and evaluation in the simulator are able to assist ophthalmologists along their surgical training.

Keywords: Phacoemulsification cataract surgery, Surgical training, Medical simulator, Virtual reality, Haptic device.

Automatic Cooling System Using PIC 18F4550 For Solar Panel

Solar photovoltaic (PV) power generation is an attractive technique to reduce consumption of fossil fuels and as a renewable energy. The temperature of PV panel increases when it absorbs solar radiation, causing a decrease in efficiency. The power and efficiency of PV panel usually falls at the rate of ~0.5 %/˚C and ~0.05 %/˚C respectively as increase of ambient temperature. To actively cool the PV panel, an automatic solar cooling system is design by using DC brushless fan and DC water pump with inlet/outlet manifold. This system is needed for uniform airflow and water flow distribution at the back and front surface of PV panel. Temperature sensors were installed on the PV panel to detect temperature of PV. PIC 18F4550 was used to control the operation of DC brushless fan and water pump depending on temperature PV panel. This controller system is an intelligent system because it will run the DC hybrid cooling system when the temperature of PV panel reaches setting level that detected by temperature sensors automatically and avoid waste electrical energy.

The maximum voltage output, maximum current output and maximum power output and every change temperature on PV panel were shown to compare the performance with and without cooling system. The results showed that the PV panel with cooling system is higher in term of power output compare to without cooling system. The higher efficiency of PV panel, the payback period of the system can be shorted and the lifespan of PV panel can also be longer.

Keywords:PV panel, DC hybrid cooling system, PIC controller, Temperature, Power Output

Mitigating Interference in a Heterogeneous Wireless Network using Channel Selection

 
With the extensive development of heterogeneous wireless communication technology, combined with the advances of data acquisition, emerges a new trend of networked acquisition systems. Among this range of wireless technology, Wireless Sensor Networks (WSNs) has attracted much interest and visibility due to its huge application space. One challenge using the WSN is the short range of the sensor nodes that increases the complexity of transporting the data to a central server. The integration with Wireless Mesh Networks (WMNs) expands the communication range and allows mobility of the device. Thus, WSN can be used for forming the underlying sensing and WMN supports the network infrastructure in pervasive computing environments. However, interference is a problem as these networks share the same 2.4GHz industrial, scientific and medical (ISM) unlicensed band. The impact of the interference on the IEEE 802.11g (WMN) using OFDM modulation and on IEEE 802.15.4 (WSN) using DSSS is investigated in this research. Results from a series of experiments on the AIT wireless mesh campus network under realistic load conditions are presented. Packet retransmission and packets drop rate were measured and based on this knowledge, a channel interference classification (CIC) method is presented to identify the interfering operating channel. The method introduced is based on a technique proposed by Chowdhury et. al. for channel selection based on reference power values. This work modifies the technique to account for differences on channel spectrum characteristic found in tests on the Mesh Campus Network. A channel selection algorithm was then developed for WSN to decide on the operating transmission channel that is not under interference, hence reducing packet losses in the network. This paper will be of interest to network operators and organisations where critical information retrieval over wide area networks is required.

Keywords: Wireless sensor networks (WSNs), IEEE 802.15.4, channel interference, wireless network coexistence.