Physicochemical characteristics of Malaysian honeys influenced by storage time and temperature

Honey is a natural product that produced by honeybees or stingless bees. Consumers always found the best quality of honey by observing the physicochemical properties. However, storage time and temperature can affect the quality of honey. This study aimed to determine the physicochemical properties (moisture content, pH, water activity and turbidity) of Hutan, Kelulut, Gelam, Acacia honeys stored at different temperatures (-20, 4 and 25oC) up to 300 days and to identify the storage conditions suitable to be applied for each type of honey. The results of this study showed that the quality of Malaysian honeys were affected by the storage times and temperatures. Hutan honey was found to be very sensitive to low temperature condition. Thus, it is recommended that Hutan honey should be stored at room temperature to retain its quality.Keywords: physicochemical characteristics; storage; Malaysian honey

Splitting tensile and pullout behavior of synthetic wastes as fiber-reinforced concrete

Plastic bottles and waste wires are the most commonly discarded synthetic wastes that contribute to environmental pollution. Polyethylene terephthalate (PET) bottles act as one of the contributors to environmental pollution. One solution to environmental pollution includes recycling plastic bottle wastes as synthetic fibers and incorporating them into concrete. Therefore, pullout strengths of synthetic fibers in a concrete matrix should be investigated by conducting splitting tensile and pullout tests. Experiments of the present study used fibers from ring-shaped PET bottles with widths of 5 and 10 mm. Irregularly shaped PET bottles with 10–15 mm size, waste wires measuring 55 mm in length, and manufactured synthetic macro-fibers were also used in comparative analysis. Results indicate that an increase in fiber volume improves tensile strength of concrete. Incorporation of high-volume fiber with concrete results in a substantial amount of fibers bridging and crossing fractured sections, thereby activating failure resistance mechanisms. In comparison with irregularly shaped PET and waste wire fibers, ring-shaped fibers performed better as they are mainly designed to activate fiber yielding instead of fiber pullout. The load energy required to debond fibers and the concrete matrix was high when the surface contact area was large in comparison with that when a small surface contact area was considered. Fibers with small surface contact area easily slip under tensile stress. Thus, the surface contact area of fibers with concrete matrix allows good frictional resistance against pullout or tensile loa

MPEG-4 video transmission using distributed TDMA MAC protocol over IEEE 802.15.4 wireless technology

The issues of green technology nowadays give an inspiration to the researcher to make all the future design to be energy efficient. Medium Access Control (MAC) layer is the most effective layer to provide energy efficient due to its ability to control the physical radio directly. One of the important applications in the future is a video transmission that can be transmitted with low-cost and low power consumption. MPEG-4 is one of the international standards for moving video. MPEG-4 provide better compression and primarily design at low bit rate communication. In order to achieve good quality for video application, the design at MAC layer must be strong. Therefore, to increase the performance of the MPEG-4 in IEEE 802.15.4, in this paper we propose a cross layer design between MAC layer and Application layer. A priority queue will be implemented at MAC scheduling depends on the level of frame important in MPEG-4 format frame. A distributed Time division Multiple Access (TDMA) will be used for MAC protocol to provide reliable data transmission for high priority frame

Strength and physical properties of concrete brick at elevated temperature

This paper discusses the strength and physical properties of lightweight concrete brick before and after being exposed to fire. For this study, lightweight concrete brick was made up of cement, sand, expanded polystyrene (EPS) and palm oil fuel ash (POFA). EPS and POFA are replacement materials used as sand and cement replacement respectively. The percentage of replacement materials was varied, which 0%, 20%, 30%, 40% and 50% for EPS and 0%, 10% and 25% for POFA. The strength and physical properties of bricks were observed and tested before and after being exposed to elevated temperature. Fire performance test of bricks was tested using electronic furnace where the temperature of fire was 300oC, 500oC and 700oC with heating rate 10oC/min. The duration of fire test was conducted for 2 hours. Among the physical properties that have been observed are deformation of shape, discolouration and surface cracking of brick samples. Generally, the brick strength were decreased as the percentage of materials replacement increase. The reduction of strength was continued when bricks were exposed to high temperature. However, the strength of the bricks was fluctuated when been exposed to different temperature

Water Thermocline Confirms Susceptibility of Tilapia Cultured in Lakes to Streptococcus agalactiae

A study was conducted on water quality profiling to confirm susceptibility of tilapia cultured in lakes to Streptococcus agalactiae infection. A total of 1,010 and 719 tilapias of different sizes were collected from two lakes; the Kenyir and Pedu lakes, respectively. They were randomly sampled for a period of 24 months. Swabs of brain, eye and kidney were streaked directly onto blood agar before S. agalactiae was identified by the API 20 STREP kit, Slidex Strepto-kit and PCR technique. The water temperature (thermocline) and dissolved oxygen profiling were determined at 1 m intervals for up to 20 m deep. Water clarity and flow rate were also recorded using Secchi disk and a current meter. S. agalactiae was successfully isolated from both lakes throughout the year, ranging between 2 and 78%. Isolation was more frequent during the hot and dry months of both years. During this period, the mean water temperature was >29 degrees C for up to 8 m deep due to the significantly (p12 m deep. This and the slow water flow kept the water temperature at 4 m deep where tilapias under the cage culture system were kept to remain high causing stress to tilapia and increases susceptibility to S. agalactiae. Dissolved oxygen profiling, however remained high at >5 mg L-1 for up to 8 m deep and did not give adverse effects to susceptibility of tilapia to S. agalactiae

Water Thermocline Confirms Susceptibility of Tilapia Cultured in Lakes to Streptococcus agalactiae

A study was conducted on water quality profiling to confirm susceptibility of tilapia cultured in lakes to Streptococcus agalactiae infection. A total of 1,010 and 719 tilapias of different sizes were collected from two lakes; the Kenyir and Pedu lakes, respectively. They were randomly sampled for a period of 24 months. Swabs of brain, eye and kidney were streaked directly onto blood agar before S. agalactiae was identified by the API 20 STREP kit, Slidex Strepto-kit and PCR technique. The water temperature (thermocline) and dissolved oxygen profiling were determined at 1 m intervals for up to 20 m deep. Water clarity and flow rate were also recorded using Secchi disk and a current meter. S. agalactiae was successfully isolated from both lakes throughout the year, ranging between 2 and 78%. Isolation was more frequent during the hot and dry months of both years. During this period, the mean water temperature was >29 degrees C for up to 8 m deep due to the significantly (p12 m deep. This and the slow water flow kept the water temperature at 4 m deep where tilapias under the cage culture system were kept to remain high causing stress to tilapia and increases susceptibility to S. agalactiae. Dissolved oxygen profiling, however remained high at >5 mg L-1 for up to 8 m deep and did not give adverse effects to susceptibility of tilapia to S. agalactiae

Data recovery in wireless sensor networks using network coding

Data transportation over resources constraint and noisy channel of wireless sensor network (WSN) is very challenging in term of guaranteeing the data survival along the transmission. However, with the convergence of different research areas such as routing, source and channel coding techniques, the WSN technology has successfully been tremendously developed. This paper proposes an on-the-fly data recovery (ODR) scheme using network coding in order to enhance the robustness of the network against packet loss. Along with the ODR scheme, the packet loss formulation is presented while a network model for a network coding designed is also introduced namely for erasure channel. The data generated by the sources are transferred to the destination through relay nodes via three transmission paths. In ODR process, the lost packet is recovered by a relay node by listening to the transmission of two adjacent nodes and performing the XOR operation on the listened packets. We provide the analytical study on network coding performance and conducting the simulation experiment to verify it. In the simulation studies, we have also compared the performance of the network using network coding with and without packet recovery. The result shows that the number of packet loss has been reduced significantly using the proposed scheme compared to the network with normal network coding