This paper examines the temperature profile of a building material and also a
built space. The study directly examines the influence of solar radiation on
building material and the heat it generated and diffuses into the built space.
Two experiments are presented. The first look at a simple technique for
evaluating heat performance of a building material, and the second evaluates
the performance of a cross-ventilated built space with respect to solar radiation.
This paper presents the application of Solid Phase Micro Extraction (SPME) coupled with Gas Chromatography - Mass Spectrometry (GC-MS) and Gas Chromatography - Flame Ionization Detector (GC-FID) in characterizing the agarwood incense. The work involved three types of SPME fibres at 30 minute sampling time. The fibres are 50/30 μm divinylbenzene-carboxen-polydimethysiloxane (DVB-CAR-PDMS), 65 μm polydi methylsiloxane-divinylbenzene (PDMS-DVB) and 85 μm carboxen-polydimethyl siloxane (CAR-PDMS). The results showed that among the many compounds extracted by GC-MS coupled with SPME, six compounds were substantially found in high quality agarwood incense due to their high percentage area (%). They are β-maaliene, α-elemol, β-selinene, 10-epi-γ-eudesmol, agarospirol and caryophellene oxide. The finding offers a new approach for establishing the volatile profile of agarwood incense components as well as for agarwood grading and discrimination.
Clustering in Wireless Sensor Network (WSN) is one of the methods to minimize the energy usage of
sensor network. The design of sensor network itself can prolong the lifetime of network. Cluster head in
each cluster is an important part in clustering to ensure the lifetime of each sensor node can be preserved
as it acts as an intermediary node between the other sensors. Sensor nodes have the limitation of its
battery where the battery is impossible to be replaced once it has been deployed. Thus, this paper
presents an improvement of clustering algorithm for two-tier network as we named it as Multi-Tier
Algorithm (MAP). For the cluster head selection, fuzzy logic approach has been used which it can
minimize the energy usage of sensor nodes hence maximize the network lifetime. MAP clustering
approach used in this paper covers the average of 100Mx100M network and involves three parameters
that worked together in order to select the cluster head which are residual energy, communication cost
and centrality. It is concluded that, MAP dominant the lifetime of WSN compared to LEACH and SEP
protocols. For the future work, the stability of this algorithm can be verified in detailed via different data
and energy.
Agarwood or gaharu, due to its unique scent and quality is considered one of the most expensive wood in the world. This paper uses solvent trap, Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) to establish agarwood quality, and is part of ongoing research. The result showed that monoterpenes hydrocarbon, sesquiterpenes hydrocarbon and oxygenated sesquiterpene contribute to agarwood smoke. Among many compounds extracted, 2-hydrdoxy-benzaldehyde, β-selinene and guaia-1(10),11-dien-15,2-olide were found dominant in monoterpenes hydrocarbon, sesquiterpenes hydrocarbon and oxygenated sesquiterpenes respectively. This finding pointed to the utility of solvent trap in extracting chemical compounds of agarwood smoke. This study is also useful for further research on establishing the grade of agarwood.
Artificial neural network (ANN) was used in this study to determine water turbidity by using back propagation algorithm. Three wavelengths which represent reflectance intensity for eight standard samples were used as training input. The finding from the study shows that the trained network with number of epochs of 250,000 and learning rate of 0.001 gave the lowest sum of squared error (SSE) of 0.04. ANN was able to predict the turbidity of water based on the pattern recognition of the reflectance spectrum. The architecture of optimized ANN used in this study was 3:25:1. The average prediction error was 0.02.
[Jaringan neural tiruan (ANN) dengan lagoritma perambatan balik (BP) telah digunakan dalam kajian ini untuk menentukan kekeruhan air. Tiga panjang gelombang yang mewakili serapan bagi lapan sampel telah dipilih sebagai imput latihan. Hasil kajian menunjukkan bagi jaringan terlatih dengan bilangan ulangan latihan 250,000 dan kadar pembelajaran 0.001 telah memberikan nilai SSE yang terendah iaitu 0.04. Dalam kajian ini jaringan ANN didapati boleh menentu dan meramalkan nilai kekeruhan sample air berdasarkan corak serapan pantulan. Arkitektur yang sesuai bagi kajian ini adalah 3:25:1. Purata ralat ramalan adalah 0.02].
Today, electromagnetic wave theory is commonly used in many engineering devices. However, such devices produce electromagnetic (EM) radiation, damaging people's health and the impact of other electronic device's operation. Therefore, Microwave Absorber has been widely used in anechoic chamber to measure equipment radiation and prevent unwanted radiation and electromagnetic interference. This research investigates the absorption performance of pyramidal absorbers with a slotted method design. This research used rectangular and triangular slotted on the hollow pyramidal absorber. There are six types of slotted: Design 1, Design 2, and Design 3
which have triangular shapes, and Design 4, Design 5, and Design 6, have rectangular shapes. The pyramidal absorber is produced using CST Microwave Studio Suite. Afterward, the fabrication process is performed using cardboard and coated with Powdered Activated Carbon (PAC). Measurement had been done successfully via far-field measurement using an arch method at 1 GHz to 12 GHz. The slotted pyramidal absorber's absorptivity was taken in each frequency band and was tabulated in figure 10. The result is compared with their maximum absorption in each of the four frequency bands. Comparison based on slot design, triangular and rectangular each had its own advantages at a certain frequency. However, small rectangular slot of Design 1 shows consistent absorption performance at all frequency band.