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This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90 wt/wt%). Microstructural analysis of the porous hydroxyapatite/starch composites was carried out by using scanning electron microscopy. It shows that the formation of hierarchical porous microstructures with high porosity is more significant at a high starch proportion. The complex modulus and complex impedance analysis were conducted to investigate the electrical conduction mechanism of the hydroxyapatite/starch composites via dielectric spectroscopy within a frequency range from 5 MHz to 12 GHz. The electrical responses of the hydroxyapatite/starch composites are highly dependent on the frequency, material proportion, and microstructures. High starch proportion and highly porous hierarchical microstructures enhance the electrical responses of the hydroxyapatite/starch composite. The material proportion and microstructure features of the hydroxyapatite/starch composites can be indirectly reflected by the simulated electrical parameters of the equivalent electrical circuit models.

A packaging material that is environment-friendly with excellent mechanical and physicochemical properties, biodegradable and ultraviolet (UV) protection and thermal stability was prepared to reduce plastic waste. Six different concentrations of Pennisetum purpureum/Napier cellulose nanowhiskers (NWCs) (i.e. 0, 0.5, 1.0, 1.5, 2.0, and 3.0 wt%) were used to reinforce polylactic acid (PLA) by a solvent casting method. The resulting bionanocomposite film samples were characterised in terms of their morphology, chemical structure, crystallinity, thermal degradation and stability, light transmittance, water absorption, biodegradability, and physical and mechanical properties. Field-emission scanning electron microscopy showed the excellent dispersion of NWC in the PLA matrix occurred with NWC concentrations of 0.5–1.5 wt%. All the bionanocomposite film samples exhibited good thermal stability at approximately 343–359 °C. The highest water absorption was 1.94%. The lowest transparency at λ800 was 16.16% for the PLA/3.0% NWC bionanocomposite film, which also has the lowest UVA and UVB transmittance of 7.49% and 4.02%, respectively, making it suitable for packaging materials. The PLA/1.0% NWC film exhibited the highest crystallinity of 50.09% and high tensile strength and tensile modulus of 21.22 MPa and 11.35 MPa, respectively.

Herein, the influence of distilled water and alkaline solution on the scratch resistance properties of Napier fibre filled epoxy (NFFE) composites were investigated. The particulate Napier fibre form was mixed with epoxy resin to fabricate 5, 10, and 15 wt.% NFFE composites. Moisture exposure tests using distilled water and alkaline solutions were conducted to determine the critical time conditions of the composites. Scratch tests were performed to investigate the scratch resistance properties of the NFFE composites, such as critical normal load, coefficient of friction, penetration depth, fracture toughness and tearing extent. The results showed that with the increasing fibre content of the composites, the scratch resistance properties increased after exposure to distilled water and an alkaline solution. The 10 wt.% NFFE composites had the highest critical normal load and fracture toughness after exposure to distilled water and alkaline solution. Morphological observations showed that severe tearing occurred for all NFFE composites after exposure to the alkaline solution compared to distilled water.

This paper presents the correlation between the morphological characteristics and the diffuse reflectance (optical properties) of the porous hydroxyapatite/cornstarch (HAp/Cs) composites with various starch proportions (30, 40, 50, 60, 70, 80 and 90 wt%). The porous composites were measured via SEM and enhanced by image processing to find the average pore size, strut width, and average surface roughness. The average porosity of the porous composites was measured using liquid displacement method. The diffuse reflectance spectroscopy was implemented to investigate the diffuse reflectance and the corresponding optical band gap energy of the porous composites in the 500–900 nm range. A relationship between morphological characteristics and diffuse reflectance properties were established using Pearson's correlation coefficient. The findings of the study depict that a strong correlation can be noticed between optical band gap energy with porosity, pore sizes and surface roughness of the porous composites. Meanwhile, the strong correlations between the diffuse reflectance spectral gradient with surface roughness can be observed. The moderate correlations can be observed between the diffuse reflectance spectral gradient with pore sizes and strut width of the porous composites.

This paper aims to investigate the dielectric properties, i.e., dielectric constant (ε′), dielectric loss factor (ε″), dielectric tangent loss (tan δ), electrical conductivity (σ), and penetration depth (Dp), of the porous nanohydroxyapatite/starch composites in the function of starch proportion, pore size, and porosity over a broad band frequency range of 5 MHz–12 GHz. The porous nanohydroxyapatite/starch composites were fabricated using different starch proportions ranging from 30 to 90 wt%. The results reveal that the dielectric properties and the microstructural features of the porous nanohydroxyapatite/starch composites can be enhanced by the increment in the starch proportion. Nevertheless, the composite with 80 wt% of starch proportion exhibit low dielectric properties (ε′, ε″, tan δ, and σ) and a high penetration depth because of its highly interconnected porous microstructures. The dielectric properties of the porous nanohydroxyapatite/starch composites are highly dependent on starch proportion, average pore size, and porosity. The regression models are developed to express the dielectric properties of the porous nanohydroxyapatite/starch composites (R2 > 0.96) in the function of starch proportion, pore size, and porosity from 1 to 11 GHz. This dielectric study can facilitate the assessment of bone scaffold design in bone tissue engineering applications.

Mechanistic studies of the interaction of electromagnetic (EM) fields with biomaterials has motivated a growing need for accurate models to describe the EM behavior of biomaterials exposed to these fields. In this paper, biodegradable bone scaffolds were fabricated using Wangi rice starch and nano-hydroxyapatite (nHA). The effects of porosity and composition on the fabricated scaffold were discussed via electrical impedance spectroscopy analysis. The fabricated scaffold was subjected to an electromagnetic field within the X-band and Ku-band (microwave spectrum) during impedance/dielectric measurement. The impedance spectra were analyzed with lumped-element models. The impedance spectra of the scaffold can be embodied in equivalent circuit models composed of passive components of the circuit, i.e., resistors, inductors and capacitors. It represents the morphological, structural and chemical characteristics of the bone scaffold. The developed models describe the impedance characteristics of plant tissue. In this study, it was found that the ε′ and ε″ of scaffold composites exhibited up and down trends over frequencies for both X-band and Ku-band. The circuit models presented the lowest mean percentage errors of Z′ and Z″, i.e., 3.60% and 13.80%, respectively.

This paper presents the development of user-friendly MATLAB-based computer-aided design (CAD) tool for microwave hybrid branch-line coupler design. The CAD is capable of predicting the characteristic impedance and the dimensions of the branch lines. In addition, the CAD also shows the output results in graph of S-parameters versus operating frequencies. The CAD can be used to design three kinds of branch-line couplers, namely single, double, and three sections branch-line couplers. The important analytical formulations which are implemented in this CAD are briefly described. Those formulations are derived using ABCD matrix, transmission line principle, and even–odd mode decomposition techniques. Hence, this CAD has simple guide user interface (GUI) display and fast program running time compared to iterative solution or numerical-based CAD. The accuracy of the CAD output results is validated by comparing to measurement and simulation results obtained from commercial simulator.

Hydroxyapatite (HA) has been widely used as a scaffold in tissue engineering. HA possesses high mechanical stress and exhibits particularly excellent biocompatibility owing to its similarity to natural bone. Nonetheless, this ceramic scaffold has limited applications due to its apparent brittleness. Therefore, this had presented some difficulties when shaping implants out of HA and for sustaining a high mechanical load. Fortunately, these drawbacks can be improved by combining HA with other biomaterials. Starch was heavily considered for biomedical device applications in favor of its low cost, wide availability, and biocompatibility properties that complement HA. This review provides an insight into starch/HA composites used in the fabrication of bone tissue scaffolds and numerous factors that influence the scaffold properties. Moreover, an alternative characterization of scaffolds via dielectric and free space measurement as a potential contactless and nondestructive measurement method is also highlighted.

Napier grass fibre was utilized for the development of biocomposite through nanocrystalline cellulose (NCC). NCC was generated by 64 wt% sulphuric acid in the hydrolysis cycle with 60 min time reaction. Biocomposite in film form has been prepared by mixing Poly (lactic acid) (PLA) and NCC using a method of solvent casting. In manufacturing of biocomposite films, NCC with different composition (0, 3, and 6 wt%) was used. The result of XRD analysis displayed an increase of crystallinity for PLA/NCC film compared to pure PLA film. However, PLA/NCC film with 6 wt% content of NCC (PLA/NCC-6) exhibited the highest percentage of crystallinity (69%). The chemical interaction of the structure between the NCC filler and the polymer matrix was studied using FTIR which confirmed by the presence of hydrogen bonding and the same trend of spectra was observed due to existence of PLA. PLA/NCC-3 demonstrated the lowest water absorption (0.37%) compared to pure PLA and PLA/NCC-6 film.

An investigation on relationship among the physicochemical, optical and dielectric properties of the hydroxyapatite/cornstarch (HA/Cs) composites with the starch proportion of 30, 40, 50, 60, 70, 80 and 90 wt% is presented in this work. The HA/Cs composites have been characterized via FTIR, XRD, DRS and impedance analyzer. This work depicts that the strong interaction is exhibited between the hydroxyapatite nanoparticles and starch as the starch proportion increases. This increment trend results in the higher crystallinity of the HA/Cs composites. The highly crystallized HA/Cs with hydroxyapatite nucleation center presents low optical properties (diffuse reflectance and optical band gap energy). The HA/Cs composite with 80 wt% starch proportion (H2C8) show higher dielectric properties (dielectric constant, loss factor and conductivity) due to the stronger interfacial interaction and close-packed HA/Cs crystalline structure. The relationship among the physicochemical, optical and dielectric properties of the HA/Cs composite is studied in this work for potential of instrumentation design.

Noise from the vehicles is one of the noise pollution to the environment. The noises emitted by the vehicles have to obey the requirement of regulation of maximum sound pressure level permitted for respective vehicles. In this study, the aim is to reduce the noise emitted from the motorcycle muffler. The noise emitted from the motorcycle muffler is analyzed and measured using a sound level meter. The average sound pressure level of the motorcycle muffler is determined in certain conditions. The sound pressure level is obtained from original motorcycle muffler, when it is under constant speed (10 km/hr, 20 km/hr, 30 km/hr) and under acceleration (in the scope of 0 km/hr to 30 km/hr). The study is continued by using a modified motorcycle muffler which contains sound absorptive materials. The absorptive materials chosen are glass wool, cotton and Styrofoam and they are taking turn to be placed into the motorcycle muffler to reduce the sound pressure level. Then the experiment is repeated. It is found that Styrofoam does not perform significantly in absorbing sound or noise in this study. Glass wool demonstrates relatively better sound energy absorption compared with cotton. In general, soft and porous materials are considered good performance in sound absorption. Denser materials are better at soundproofing or sound blocking. Therefore, glass wool with relatively higher density among the investigated absorptive materials in this study has the greatest sound absorption performance.

The aim of this study is to investigate the morphological, functional group, crystallinity and mechanical properties of a three-dimensional porous cornstarch/n-HAp (nano-hydroxyapatite) biocomposite scaffold. In this study, cornstarch/n-HAp scaffolds were fabricated using the solvent casting and particulate leaching technique. The porous cornstarch/n-HAp composites with various cornstarch contents (30, 40, 50, 60, 70, 80 and 90 wt%) were prepared and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometer and compression test. The morphology of the scaffolds possessed macropores (200–600 μm) and micropores (50–100 μm) with a high interconnectivity. The porosity of the porous cornstarch/n-HAp scaffolds varied between 53 and 70% with compressive strength and compressive modulus of 2.03 and 8.27 MPa, respectively. The results suggested that highly porous cornstarch/n-HAp scaffold properties with adequate mechanical properties can be obtained for applications in bone tissue engineering.

This paper provides a comprehensive analysis of the dielectric and physicochemical properties of the porous hydroxyapatite/cornstarch (HAp/Cs) composites in a new perspective. The porous composites have been characterized via SEM, FTIR, XRD and dielectric spectroscopy. The dielectric permittivity spectra were obtained in Ku-band (12.4–18.0 GHz) and it was correlated with the physicochemical properties of the porous HAp/Cs. Porous HAp/Cs composites exhibits low e′ and negative e″, which influenced by the microstructural morphology, interaction between Hap and Cs, as well as crystalline features due to the various proportion of the HAp/Cs. The physicochemical effect of the composites results in the dielectric polarization and energy loss. This phenomenon indicates the presence of the three obvious relaxation responses in the e′ spectrum (13.2–14.0, 15.2–16.0, and 16.6–17.4 GHz) and the negative behaviours in the e″ spectrum. The relationships between physicochemical and dielectric properties of the porous composite facilitate the development of the non-destructive microwave evaluation test for the porous composite.

This chapter reviews the microwave complex ratio measuring (MCRM) circuits which are used for complex reflection coefficient measurement. This MCRM circuit is relatively simple and cost-effective. There are various structures for the MCRM circuit, such as multi-probe transmission line circuits, five-port ring circuits, six-port hybrid coupler-based circuits, switched-reflector circuits, dual-generator circuits, and Wheatstone bridge-based circuits. Each structure of the circuits has its own advantages and disadvantages. In this chapter, the MCRM circuit calibration process has been described in detail.

Hydroxyapatite (HA) which is a group of calcium phosphate (CaP) is used as a medical devices coating due to its ability to increase the bioactivity and biocompatibility of the device surface. The attraction of using waste seashells products is interesting due to its sustainability and low cost solution especially in biomedical application. Polymesoda expansa or locally known as Lokan is potentially rich with calcium carbonate (CaCO3). Here, the synthesis of HA was done via precipitation method by utilizing the Polymesoda expansa (Lokan) shells as the resource of calcium precursors. Hydroxyapatite synthesized from Polymesoda expansa was carried out with different pH solution (pH 9 and 13) in alkaline environment. The effects of pH on the morphological and chemical composition properties as well as the Ca/P ratio of HA powders were analyzed through Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Energy Dispersive X-ray Spectrometry (EDS). The finding demonstrates as the pH increases, the calcium apatite reduced and this had increases the Ca/P ratio.

In this paper, a microwave transmission line sensor is investigated and used for bulk liquid permittivity measurement. A microstrip type transmission line is designed and analysed for a frequency range of 150 kHz to 8 GHz. The transmission coefficient magnitude of the microstrip line covered with different liquid samples is calculated numerically and compared with the measurement results. The calculated transmission coefficient magnitudes show good agreement with the normalized measurement results for the sample with a dielectric constant of less than 30 and a frequency range up to 6 GHz. A specific focus of the work is to study the transmission response of the microstrip line sensor when it is implemented on a curved substrate instead of the traditional planar substrate. A semi-flexible microstrip line is designed using a semi-rigid substrate for different curvature and its transmission coefficient is calculated numerically. The curved microstrip line sensor shows good agreement between the calculated and the measured results with minimum effect on the curvature. Furthermore, dielectric constant empirical models are formed and tested for unknown liquid samples. The results show a good match between the microstrip line sensor and the commercial dielectric probe for the determination of dielectric constant at frequency range less than 0.5 GHz and 4 to 8 GHz. The study demonstrated that the empirical models applied for the dielectric constant determination can be developed for low dielectric constant liquid despite of the sensor structure is curved or planar.

In this paper, a low-cost portable microwave reflectometer is designed and developed to measure glucose content in aqueous solution. The proposed microwave measurement system is constructed by using microwave circuit with a non-invasive open-ended coaxial probe sensor. Reflection method is used due to its simplicity and suitability of detecting the glucose concentration. The reflected microwave signal is detected by coaxial probe sensor and converted into voltage signal using power detector. Empirical models between the reflection coefficient and the glucose concentration from 10% to 60% have been developed. The reflectometer measurements are compared with Vector Network Analyser, and validated using different batch of samples. The proposed reflectometer demonstrates reasonable accuracy with an error of less than 4.5%.

In this study, the effects of thermal ageing on the scratch-resistance properties of natural-fibre-reinforced epoxy composites were investigated. Jute, kenaf and hemp-fibre-reinforced epoxy composites were fabricated using the vacuum infusion method. The natural-fibre-reinforced composites were exposed to thermal ageing for 7, 15, and 30 d at 90 °C temperature. Scratch tests were carried out using a CSM Revetest Xpress machine. The scratch resistance properties, such as the critical normal load, coefficient of friction, penetration depth, fracture toughness, scratch hardness, and scratch tearing were determined after thermal ageing. The results demonstrate that the scratch resistance of the composites decreased as the thermal ageing time increased. However, the jute-fibre-reinforced epoxy composites had the highest critical normal load, fracture toughness and scratch hardness compared to those of kenaf and hemp-fibre-reinforced epoxy composites after 30 d of thermal ageing.

Finite difference analysis were applied to study the principle operation of monopole antenna for moisture determination in oil palm fruit at 2 GHz. The electromagnetic field interact with oil palm fruit on the interface between the antenna and oil palm fruit and cause a reflection. The reflection measurement is based on mismatch impedance or dielectric properties between two media. Reflection coefficient is used to quantify the level of reflection. The monopole antenna was made of RG405/U semi-rigid coaxial cable with an inner and outer diameter of 0.45 mm and 1.50 mm, respectively with 2.23 mm length of protruding conductor over 5.66 cm length of monopole antenna. This monopole antenna for moisture detection was compared with induced EMF method in terms of reflection coefficient at 2 GHz. The results show that the complex reflection coefficient measured using monopole antenna provides significant results to predict moisture content in oil palm fruit.

The effect of natural filler loading, multi-walled carbon nanotubes (MWCNTs), and moisture absorption on the dielectric constant of natural filled epoxy composites was investigated. The natural filled epoxy composites were fabricated using a natural filler, MWCNTs and epoxy resin. The natural fillers chosen were Jute, Kenaf, and Napier. Composites were manufactured using a cold-press method, with the loading of the natural fillers being 7, 14, and 21 vol%, respectively, while the MWCNTs were 0 and 2 vol%. Dielectric tests were conducted using an Agilent/Keysight E8363B PNA Network Analyser in dry and wet conditions. The moisture absorption curves indicate that higher vol% natural filler loading increases the moisture content of the composites. The results show that the Napier filled epoxy composite had the lowest dielectric constant between 12.40 GHz and 16.66 GHz. The presence of 2 vol% MWCNTs successfully decreased the dielectric constant for 7 vol% Jute filled epoxy composites.

Sujud (prostration) is one of the main pillars of a Muslim’s prayer. It involves seven limbs as derived from the sayings or the acts of Prophet Muhammad (peace be upon him) or the hadiths. However, the correct way in pertaining to sujud has received different opinions from Muslim scholars. The differences are based on the hadiths and there are two different ways of acts interpreted by Muslim scholars which are: preceding by hands or preceding by knees. Thus, this study investigated the differences in terms of statistical analysis using electromyography signals (EMG) of the lower limbs muscles, specifically the Gastrocnemius and Tibialis Anterior Muscles. Here, it was shown that there was no significant difference between the muscles on these postures of solat, although there are different opinions on the way of pertaining to sujud based on the authenticity of the hadiths and also their interpretation by the scholars.

This paper presents an ultra-wideband (UWB) and off-optimised Five-Port Reflectometer (FPR) configured by power splitters. The proposed non-multi-state FPR is characterised and realised for complex reflection coefficient determinations. The measurement system can be easily setup using commercial power splitters, three detectors and a microwave source. The transmission lines method is used as calibration standard for FPR measurement system. Both the FPR setup and the transmission lines are characterised with a Vector Network Analyser prior to be used for the off-optimised measurement system. The results show good agreement between actual and calculated reflection coefficient for frequency range of 0.1 to 40 GHz. This novel FPR setup provides a simple, cost effective and accurate alternative in measuring broadband complex reflection coefficient.

This paper presents tea leaves moisture monitoring system based on RF reflectometry techniques. The system was divided into two parts which are the sensor and reflectometer parts. The large coaxial probe was used as a sensor of the system. The reflectometer part plays a role as signal generator and also data acquisition. The reflectometer-sensor system was operated with a graphical user interface at 1.529 GHz at room temperature. The system was able to measure the moisture content of tea leaves ranging 0% m.c to 50% m.c on a wet basis. In this study, up to five kinds of tea leaves bulk were tested. The mean of absolute errors in the moisture measurement for tea leaves was ±2.

This paper is to study the dielectric properties, magnetic properties, and dielectric conductivity of Multi-walled carbon nanotubes (MWCNTs) and polyester (PE) composites. The composites with different amount of MWCNTs (5-15%) have been studied in the Ku-Band range (12.4-18 GHz). The rectangular waveguide (WR-62) was used to measure the dielectric properties and magnetic properties of the samples. The results show the dielectric properties and conductivity of MWCNTs/PE composites is increasing with the MWCNTs filler increases. The real part of dielectric properties values increase from 5.5 to 26.6 with increasing the MWCNTs loading from 5 % to 15 %. The increasing of MWCNTs filler in the MWCNTs/PE composites does not effects on magnetic properties, the real part and imaginary part of magnetic properties are approximate to 1 and 0. The highest conductivity of 15 % MWCNTs loading is reach to 11.02 (S/m) at 18 GHz. Keywords: composites, dielectric properties, magnetic properties, conductivity

Six-port reflectometer is well-known for its abil- ity to measure magnitude and phase-shift of microwave signal using four power detectors that perform magnitude- only measurements. This paper presents the development of an innovative symmetric ring junction as four-port re- flectometer for complex reflection coefficient measure- ments. It reduces the number of required detectors to two. Design optimization, new calibration modeling and algo- rithm are discussed in details for this four-port reflectome- ter. The developed four-port reflectometer is compared to five-port reflectometer and vector network analyzer. It is found that the measured magnitude and phase-shift show good performance in comparison with the commercial vector network analyzer and the five-port reflectometer.

Fabrication of an impedance tube for measuring sound absorption coefficient is presented in this paper. Transfer-function method is chosen for the sound absorption analysis. The impedance tube is designed and fabricated in accordance with ISO 10534-2. The tube is made from brass with diameter of 114.3 mm and length of 1.42 m. It is designed for the frequency range 60 Hz to 1800Hz. Three microphone positions are installed to achieve the frequency range with a single tube. The theoretical background of transfer-function method between two microphones is discussed. Initially, impedance tube is characterized by the measurement without testing material in the tube. Micro-perforated panel (MPP) with 50 mm and 100 mm of cavity depth are used for measurement. The sound absorption coefficient measurement of the MPP is compared with theory and good agreement is achieved. Various problems related to design and construction is addressed and the optimal configuration is presented.

Oil palm evacuation are still labour dependent and room for mechanisation may still exist. With the importance of this industry as one of nation’s economic contribution the efforts are still considered viable. In order to reduce, improve and empower labours a new concept design was developed. A mock-up interaction was done in virtual environment in order to assess the ergonomic aspect of the design in order to determine the pros and cons of the concept design. The findings had led to a conclusion for a requirement of a more thorough assessment to assess human machine interaction in terms of biomechanical effects.

Most of Napier grass industry in Malaysia is labored in small and medium scale. Therefore, the harvesting works are done manually by man power using conventional equipment such as sickle and machete. However, there are some efforts made to design the low cost equipment in assisting this Napier grass harvesting works. The aim of this study is to compare the Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA) performance in order to evaluate the certain body parts condition during harvesting works by using conventional equipment and innovation machine assisted. Based on survey, conventional harvesting method might increase the risk of low back pain (LBP) due to repetitive stooping posture. Furthermore, the back biomechanical load and force impact were also not handling wisely. The objective of this study is to prove that the usage of machine during harvesting works might improve the body posture especially on stoop level condition. Based on results, the overall RULA and REBA score are excellently improved as well as trunk position which is depicts the stooped level condition. Hence, the innovation of harvest machine could contribute to the Napier grass industry especially on small and medium entrepreneur.

Inspired by research technology of RFID in flexible substrate, a new era of microwave sensor in more flexible form is indeed an interesting and important research area. One of the most common and suitable microwave sensor that suitable to be transformed into flexible structure is microstrip. In this project, a semi-flexible microstrip sensor was designed and simulated with soft substrate for difference curvature angles. The sensor was investigated and critically analyzed to study the effects of curvature. The designed sensor was fabricated and experimental result are measured by Vector Network Analyzer for frequency range 150 kHz to 8 GHz. The transmission coefficient of curvature sensor that covered with sample of various dielectric values were measured. All the parameters are compared to flat microstrip sensor. The potential and performance of the curvature microstrip sensor are intensively examined.

This study was conducted to investigate the feasibility of microwave dielectric spectroscopic technique in characterizing commercial rice due to different level of moisture content. There are some unethical rice industry runner mixes good qualities of rice which can be sold at high price with low cost and quality of rice to maximize profit. It causes fraudulency in business and great lost in term of money to nation who take rice as staple food. It happens frequently in Asian country which is active in agricultural activities. This technique is implemented using Keysight E8362B network analyzer in conjunction with an Keysight 85070E dielectric probe ranging from 200 MHz to 10 GHz. The samples of study are commercially available at market, namely fragrant rice, white rice, and brown rice, respectively. These are the popular and favorite rice for Malaysian due its delicacy and affordable price. Nutrient level for fragrant rice, white rice, and brown rice in terms of protein, moisture, carbohydrate and fat are different and unique. It leads to various electromagnetic responses toward frequency. Dielectric and reflection measurement were conducted to characterize these rice. The presence of polar and non-polar molecules in nutrient of rice causes variation of dielectric and reflection behavior over the operating frequency range.

This paper presents the modelling of stress strain response of glass fibre reinforced epoxy (GRE) composite pipes subjected to multiaxial loadings at room temperature (RT). This particular modelling work was developed to predict the non-linear stress strain response caused by the fatigue cyclic and static loading in the multiaxial ultimate elastic wall stress (UEWS) tests by considering the effects of matrix cracking within the laminates. The UEWS test, whilst not yet standardized, appears to offer an attractive alternative to existing procedures of qualifying GRE pipes. The ply properties initially expressed as a function of crack density was computed as a function of increasing stress and strain using shear lag approximation. The predictions are found to be in good agreement with the data from multiaxial UEWS tests on ±55° filament wound glassreinforced epoxy pipes.

Ground penetrating radar (GPR) is a non-destructive tool for subsurface investigation becomes an emerging trend in many applications especially in detecting infrastructure utilities. However, interpreting of GPR data in terms of target’s geometry is remained a challenging task due to the existence intra/inter-class variations and subtle changes of hyperbolic signature pattern in GPR data. To addressed this issue, this paper proposes to classify the basic shape (i.e. cubic, cylindrical and disc) of buried object using multilayer perceptron neural network. The GPR raw data firstly is pre-processed based on A-scan and B- scan GPR data. Then, the combined statistical features with gray level co-occurrence matrix (GLCM) and Hu moment invariants are extracted from A-scan and B-scan. The extracted features are then fed as input to multilayer perceptron to classify the shapes (cubic, cylindrical and disc) of buried object. Based on the experiment conducted, the highest recognition rate has been achieved is about 83.3%. Thus, the proposed method of using combined statistical with GLCM and Hu moment invariants features to classify shape of buried object using multilayer perceptron is promising.