bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensing of explosive vapor by hybrid perovskites: Effect of dimensionality
Authors: Harwell J. R. , Glackin J. M. E. , Davis N. J. L. K. , Gillanders R. N. , Credgington D. , Turnbull G. A. , Samuel I. D. W.
Published: July 2020

Lead halide perovskites are very promising materials for many optoelectronic devices. They are low cost, photostable, and strongly photoluminescent materials, but so far have been little studied for sensing. In this article, we explore hybrid perovskites as sensors for explosive vapor. We tune the dimensionality of perovskite films in order to modify their exciton binding energy and film morphology and explore the effect on sensing response. We find that tuning from the 3D to the 0D regime increases the PL quenching response of perovskite films to the vapor of dinitrotoluene (DNT)—a molecule commonly found in landmines. We find that films of 0D perovskite nanocrystals work as sensitive and stable sensors, with strong PL responses to DNT molecules at concentrations in the parts per billion range. The PL quenching response can easily be reversed, making the sensors reusable. We compare the response to several explosive vapors and find that the response is strongest for DNT. These results show that hybrid perovskites have great potential for vapor sensing applications.
Foreign accent, comprehensibility and intelligibility, redux
Authors: Munro Murray J. , Derwing Tracey M.
Published: July 2020

We revisit Munro and Derwing (1995a), providing retrospective
commentary on our original methods and findings. Using what are now well-established assessment techniques, the study examined the
interrelationships among accentedness, comprehensibility, and intelligibility in the speech of second-language learners. The key
finding was that the dimensions at issue are related, but partially independent. Of particular note was our observation that
speech can be heavily accented but highly intelligible. To provide a fresh perspective on the original data we report a few new
analyses, including more up-to-date statistical modeling. Throughout the original text we intersperse insights we have gained over
the past 25 years. We conclude with retrospective interpretations, including thoughts on the relevance of the study to
contemporary second language teaching and especially pronunciation instruction.
Ultra-low permittivity porous silica-cellulose nanocomposite substrates for 6G telecommunication
Authors: Pálvölgyi Petra S , Nelo Mikko , Pitkänen Olli , Peräntie Jani , Liimatainen Henrikki , Myllymäki Sami , Jantunen Heli , Kordas Krisztian
Published: July 2020

The continuously increasing demand for faster data traffic of our telecommunication devices requires new and better materials and devices that operate at higher frequencies than today. In this work, a porous composite of silica nanoshells and cellulose nanofibers is demonstrated as a suitable candidate of dielectric substrates to be used in future 6G frequency bands. The hollow nanospheres of amorphous SiO2 with outstanding electromagnetic properties were obtained by a template-assisted Stöber process, in which a thin shell of silica is grown on polystyrene nanospheres first, and then the polymer core is burned off in a subsequent step. To be able to produce substrates with sufficient mechanical integrity, the nanoshells of SiO2 were reinforced with cellulose nanofibers resulting in a porous composite of very low mass density (0.19 ± 0.02 g cm−3), which is easy to press and mold to form films or slabs. The low relative dielectric permittivity (ε
r = 1.19 ± 0.01 at 300 GHz and ε
r = 1.17 ± 0.01 at 2.0 THz) and corresponding loss tangent (tan δ= 0.011 ± 0.001 at 300 GHz and tan δ = 0.011 ± 0.001 at 2.0 THz) of the composite films are exploited in substrates for radio frequency filter structures designed for 300 GHz operation.
Nanosecond pulsed discharges in distilled water: I. Continuum radiation and plasma ignition
Authors: Grosse K , Schulz-von der Gathen V , von Keudell A
Published: July 2020

Nanosecond plasmas in liquids are an important method to trigger the water chemistry for electrolysis or for biomedical applications in plasma medicine. The understanding of these chemical processes relies on knowing the variation of the temperatures in these dynamic plasmas. This is analyzed by monitoring nanosecond pulsed plasmas that are generated by high voltages at 20 kV and pulse lengths of 15 ns applied to a tungsten tip with 50 μm diameter immersed in water. Plasma emission is analyzed by optical emission spectroscopy ranging from UV wavelengths of 250 nm to visible wavelengths of 850 nm at a high temporal resolution of 2 ns. The spectra are dominated by the black body continuum from the hot tungsten surface and line emissions from the hydrogen Balmer series. Typical temperatures from 6000 K up to 8000 K are reached for the tungsten surface corresponding to the boiling temperature of tungsten at varying tungsten vapor pressures. The analysis of the ignition process and the concurrent spectral features indicate that the plasma is initiated by field ionization of water molecules at the electrode surface. At the end of the pulse, field emission of electrons can occur. During the plasma pulse, it is postulated that the plasma contracts locally at the electrode surface forming a hot spot. This causes a characteristic contribution to the continuum emission at small wavelengths.
Polarization control of radiation and energy flow in dipole-coupled nanorings
Authors: Cremer J , Plankensteiner D , Moreno-Cardoner M , Ostermann L , Ritsch H
Published: July 2020

Collective optical excitations in dipole-coupled nanorings of sub-wavelength spaced quantum emitters exhibit extreme sub-radiance and field confinement facilitating an efficient and low-loss ring-to-ring energy transfer. We show that energy shifts, radiative lifetimes, and emission patterns of excitons and biexcitons in such rings can be tailored via the orientation of the individual dipoles. Tilting the polarization from perpendicular to tangential to the ring dramatically changes the lifetime of the symmetric exciton state from superradiance to subradiance with the radiated field acquiring orbital angular momentum. At a magic tilt angle all excitons are degenerate and the transport fidelity between two rings exhibits a minimum. Further simulations suggest that, for certain parameters, the decay decreases double-exponentially with the emitter’s density. Disorder in the rings’ structure can even enhance radiative lifetimes. The transport efficiency strongly depends on polarization and size, which we demonstrate by simulating a bio-inspired example of two rings with 9 and 16 dipoles as found in biological light harvesting complexes (LHC). The field distribution in the most superradiant state in a full LHC multi-ring structure shows tight sub-wavelength field confinement in the central ring, while long-lived subradiant states store energy in the outer rings.
Contact engineering for two-dimensional semiconductors
Authors: Zhang Peng , Zhang Yiwei , Wei Yi , Jiang Huaning , Wang Xingguo , Gong Yongji
Published: July 2020

Two-dimensional (2D) layered materials, including graphene, black phosphorus (BP) and transition metal dichalcogenide (TMD) such as molybdenum disulfide (MoS2), tungsten diselenide (WSe2), have attracted increasing attention for the application in electronic and optoelectronic devices. Contacts, which are the communication links between these 2D materials and external circuitry, have significant effects on the performance of electronic and optoelectronic devices. However, the performance of devices based on 2D semiconductors (SCs) is often limited by the contacts. Here, we provide a comprehensive overview of the basic physics and role of contacts in 2D SCs, elucidating Schottky barrier nature and Fermi level pinning effect at metal/2D SCs contact interface. The progress of contact engineering, including traditional metals contacts and metallic 2D materials contacts, for improving the performance of 2D SCs based devices is presented. Traditional metal contacts, named 3D top and edge contacts, are discussed briefly. Meanwhile, methods of building 2D materials contacts (2D top contact and 2D edge contact) are discussed in detail, such as chemical vapor deposition (CVD) growth of 2D metallic material contacts, phase engineered metallic phase contacts and intercalation induced metallic state contacts. Finally, the challenges and opportunities of contact engineering for 2D SCs are outlined.
Exploration Sustainable Base Material for Activated Carbon Production Using Agriculture Waste as Raw Materials: A Review
Authors: Muzarpar M S , Leman A M , Rahman K A , Shayfull Z , Irfan A R
Published: July 2020

Activated carbon can be call as “material of the future” due to its versatility usage from medical aspect, water and air treatment and a very good adsorbent characteristic. Process involved in the production of activated carbon were carbonization of raw material and activation of the charcoal to be a carbonized material. Basically the activation can be either physical or chemical activation or a combination of it. This paper is to review the potential of agricultural waste and introduce the potential base material that can be utilized as raw material for activated carbon. The process and the material selected on agricultural waste is coconut shell, palm kernel shell and rubber seed shell. The downstream industry of agricultural waste could look into material for the product development in the near future.
Improving the Sonocatalytic Degradation of Caffeine by Organic Acids Treatment for Surface Modification of Ag/CeO2
Authors: Nur Fadzeelah A K , Abdullah A Z , Azha N A
Published: July 2020

In this work, the surface of Ag/CeO2 which was prepared using hydrothermal method was modified using three types of organic acid such as ascorbic acid, citric acid and oxalic acid as the post treatment of as-synthesized Ag/CeO2 catalyst. The modified catalyst was further characterized using energy dispersive X-ray (EDX) for its elemental composition and BET surface area. The sonocatalytic degradation of caffeine under ultrasonic irradiation was examined to investigate the effect of these organic acids on the modification of Ag/CeO2 catalyst. The result showed that ascorbic acid demonstrated the highest sonocatalytic degradation of caffeine compared to citric and oxalic acids. Meanwhile, the degradation of caffeine was improved from 72.8% to 78.9% for modified Ag/CeO2 catalyst using ascorbic acid as the surface modifier. Thus, this result indicates that this kind of organic acid might have potential to modify Ag/CeO2 catalyst surface and improve the sonocatalytic degradation of caffeine.
Effect of Sythesis Conditions of Cr-Ti Mixed Oxides on FAME and Catalyst Characteristics
Authors: Samin M.S. , Wan Zuraida , Yazid N. , Ali Bashah N.A. , Hassan H. , Nur Fadzeelah A.K. , Jamaludin S.K. , Sabrina Mohd Sukri Siti
Published: July 2020

Biodiesel or fatty acid methyl ester (FAME) is one of the best alternative renewable energy source and environmental friendly fuel to replace diesel. Cr-Ti mixed oxides catalysts were synthesized via sol-gel method for the transesterification of cooking palm oil (CPO) to produce FAME. The reactions were conducted in a batch reactor. The effects of calcination time and ethanol solvent volume were studied. The calcination time of the Cr-Ti mixed oxides between 1 h to 5 h and ethanol volume between 20 mL to 60 mL shows effect on the FAME density obtained in the reaction. It was also observed that calcination time affects the catalyst surface area, pore diameter and pore volume. The results shows that the Cr-Ti catalyst prepared at 2 h calcination time with 50 mL ethanol volume has the highest surface area, pore volume and pore diameter among the prepared catalysts and obtained FAME density of 841.5 kg/m3. The FAME density is within the value range of the biodiesel fuel property. Thus, Cr-Ti mixed oxides catalyst shows good potential as heterogenesous catalyst for transesterification of CPO to produce FAME.
Compressive Strength of Fly Ash Geopolymer Concrete by Varying Sodium Hydroxide Molarity and Aggregate to Binder Ratio
Authors: Aida Mohd Mortar Nurul , Kamarudin H. , Rafiza R. A. , Meor T.A.F , Rosnita M
Published: July 2020

The concentration of sodium hydroxide solution increased the reaction rate during geopolymerisation process and thus enhanced the development of early strength of concrete. While the percentage volume of aggregates played a vital role in the strength development due to the better durability then paste alone and also filling and packing ability. The aim of the study is to determine the optimum molarity of sodium hydroxide and aggregate to binder ratio of geopolymer concrete towards high strength performance concrete based on compressive strength. The variable samples investigated include the sodium hydroxide (NaOH) concentration and aggregate to binder ratio at room temperature curing; the ratio of alkali activator solution and solid to liquid ratio remained constant. This resulted the presents work on the development of fly ash based geopolymer concrete having increment on the rate of compressive strength development from 7 to 28 days was found between 61 MPa and 82 MPa, respectively.
Experimental Study on the Lateral Torsional Buckling Behaviour of the Triangular Web Profile Steel Section
Authors: De’nan Fatimah , Mat Yusof Hassyima , Kaur Amarpreet
Published: July 2020

A triangular web profile (TriWP) section is a structural steel section that is made of two flanges connected to a web plate of triangular profile. Only certain research works have been carried out to study the characteristic, behaviour and the advantages offered by this section compared to the normal flat web (I-beam). An area that is not given full attention is the capability of this section to resist the lateral torsional buckling moment capacity compared to that of the normal flat web. The objectives of this thesis are to study the lateral torsional buckling behaviour of Triangular Web Profile (TriWP) steel section and compare to that of the flat web by experimental and to find the value of Mb, moment buckling resistance for TriWP. The scope of study covered the experimental work and theoretical investigation of triangular web profile steel section subjected to lateral torsional buckling moment resistance. The effect of the shape of the triangular web profile beam compared to that of the flat web beam was also be studied. For the buckling moment resistance, several factors were taken into account such as buckling parameter, torsional index, warping constant and torsional constant. All these factors are related to the second moment of area with respect to minor axis. The lateral torsional buckling test includes 8 specimens (4 flat webs and 4 TriWP). Each specimen was tested in two different sizes which is 200x100x6x3 and 180x75x5x3. Findings from the lateral torsional buckling tests were compared to the manual calculation using BS 5950: Part 1:2000. The lateral torsional buckling test shows that the moment buckling resistance of the triangular web profile steel beam section is better than that of the flat web in smaller size while in bigger size flat web beam has better moment resistance than that of triangular web profile steel beam. The section properties such as width (B), depth (D), thickness of flange (tf) and thickness of web (tw) affect the buckling moment resistance, Mb of the steel section
Critical Saturation Function Based Sliding Mode Control for Path Tracking of Mobile Robot
Authors: Ning Hong-Bin , Deng Xiao-Fei , Zhu Jun-Wei , Zhou Kai-Qing
Published: July 2020

This paper proposes a new sliding mode controller, as to enhance the performance of path tracking of three-wheeled mobile robot system. To begin with, backstepping design is used to construct a new sliding mode control law for better dynamic response and robustness. Next, in order to reduce chattering, the symbolic function is replaced with the critical saturation function in the conventional reaching law. At last, the simulation results show that backstepping design combined with saturation function can not only improve the response rate and robustness of the system, but also effectively reduce the chattering.
Predictive Modelling for Hospital Readmission Risk in the Philippines
Authors: Landicho J , Esichaikul V , Sasil R
Published: July 2020

Predictive models have been developed over the years to identify patients at risk of readmission. The goal of this study is to identify the risk factors associated to a patient’s readmission within one year in the cohort study including acute myocardial infarction (AMI), Heart Failure (HF), Chronic Obstructive Pulmonary Disease (COPD) and Pneumonia (PN) in a reputed Philippine hospital. Four predictive models were used and evaluated using performance metrics. The study found Logistic Regression as the most performing model in most of the cohort studies. There are 6 to 8 variables significantly associated with the readmission of high-risk patients.
Divide Large Scale Fuzzy Petri Net into Equivalent Sub-FPNs using Reachability Tree
Authors: Liu Bi-Yu , Zhou Kai-Qing , Zarith Rahmah Syed Ahmad Sharifah
Published: July 2020

As real systems become larger and complicated, the number of nodes of fuzzy Petri net (FPN) also increases rapidly, it further indicated that the algorithm complexity of related application using FPN grows up sharply. To solve this state-explosion issue, a decomposition algorithm using reachability tree is proposed to divide a large-scale FPN model into a series of sub-FPNs in this paper. Comparison experiments show that all obtained sub-FPNs do not destroy internal reasoning paths of the original large-scale FPN and represent a complete reasoning path from input place(s) to the output place.
An Improved Harmony Search Algorithm with Segmented Search
Authors: Kang Di-Wen , Mo Li-Ping , Zhou Kai-Qing
Published: July 2020

Harmony search (HS) algorithm has received widely attention in various fields because of simple operation and outstanding performance. However, there exists some bottlenecks which hinders the further development of HS algorithm, such as easy trapping into local optimum and slow convergence velocity.This paper proposes an improvement HS algorithm by using segmented search strategy (SHS) to overcome these drawbacks. Comparative experiments reveal the proposed SHS algorithm has perfect performance, especially in high dimensions.
Application of Particle Filter in Video Moving Target Tracking
Authors: Biao-Li  , Deng Xiao-Fei , Fang-Chen  , Rui-Yan  , Zhao Si-Qi , Zhou Kai-Qing
Published: July 2020

Aiming at solving the problem of large tracking error in the tracking process of video moving targets with the unscented Kalman filtering method, a particle filter algorithm is proposed to track video moving targets to improve the tracking effect. Particle filtering is the minimum variance estimation of the system state through the posterior probability distribution. The applications of particle filtering and unscented Kalman filtering in tracking video moving target are compared by using Matlab simulation software. The results show that the particle filter has higher accuracy and better tracking performance than the unscented Kalman filter in tracking video moving target.
IoT-based Production Output Monitoring System for Plastic Packaging Manufacturing Process
Authors: Yun Yee Wong , Chang Choon Chew , Chee Siong Teo , Ambar Radzi , Helmy Abd Wahab Mohd
Published: July 2020

This paper discusses about the development of an IoT-based production output monitoring system in the production line of Chiga Light Industries Sdn. Bhd. which is a plastic packaging manufacturing company. Although the existing company Enterprise Resource Planning (ERP) system provides a platform for production manager and officers to monitor as well as collect the length of plastic film produced on a printing machine, only the total amount of finished goods in kilograms (kg) is recorded. However, the total length of plastic produced, and time taken to finish one tubing are needed for machine analysis and production planning. Therefore, a length encoder is used to detect the length of plastic film produced and connected to a counter meter to display the present value of plastic produced as well as the setting value for one roll of plastic. Besides, an Arduino board is used to read data from the counter meter while an ESP8266-01 Wi-Fi module is used to send the data to ThingSpeakTM cloud for storing. ThingSpeakTM analysed and visualised the collected present and setting values of the counter meter on a private channel. The duration for uploading a data is set to one hour. From the developed monitoring system, production manager and officers could monitor machine performance, operators working performance and collect the length of plastic produced on a printing machine. Besides, the total length of plastic in a roll could also be detected to ensure customer requirement is achieved.
IOT Real-Time People Counting Using Raspberry PI (IOT-RepCO)
Authors: Mat Din M , Nordin N N , Md Siraj M , Kadir R.
Published: July 2020

IOT - RepCO is a People Counting System that allows tracking and verification activities to be systematically carried out. This web-based system ensures that the accuracy and reliability of the information sent by the service provider company by changing the manual way to the online system. In addition, this system also allows information to be stored in digital form which indirectly creates a “paperless” environment. Security features are also enhanced by using IOT - RepCO. Python and OpenCV languages are used in the development of this system. While “ubidots” are used for data storage in “cloud”. The requirement for this solution were carried out in Datasonic Corporation Sdn. Bhd. whereby it also provides a testing ground and verification of the system. The diversity of users in this system requires user-friendly interface design as well as minimal navigation and low fidelity concept as an appeal for all users who will use the IOT -RepCO system. It is hoped that the construction of the IOT - RepCO system will assist the companies as well as other parties such as fire department during the emergency evacuation such that it indirectly improve the quality of service to the customers as well as providing an important information during evacuation process.
Combining Deep Neural Network and Fourier Series for Tourist Arrivals Forecasting
Authors: Shabri Ani , Samsudin Ruhaidah , Yusoff Yusliza
Published: July 2020

Accurate tourist arrivals forecasting is essential for governments and the private sector to formulate policies and allocate funds more effectively. In this paper, the modeling of tourist arrivals time series data was introduced in a hybrid modeling that combines the deep neural network (DNN) with the Fourier series method. The proposed model approach applies the DNN to get the forecasted value and then employs the Fourier series to fit the residual error produced by the DNN. To verify the accurate prediction of the proposed model, different single models such as ARIMA, ANN and DNN, and modified ARIMA and ANN models using Fourier series are investigated. Historical data on monthly tourist arrivals to Langkawi Island with high trend and strong seasonality is used to compare the efficiency of the proposed model. A series of studies demonstrates that the performance of the single model can be further improved by taking into account the residual modification by Fourier series. The result shows that the proposed model is capable of forecasting tourist arrival series with higher reliability than other models used.
Effects of Mixture Biochar-Fertilizer With and Without Tableting on The Soil Chemical Characteristics
Authors: Yit Leng Lee , Haruna Ahmed Osumanu , Abdul Wahid Samsuri , AB Aziz Zakry Fitri
Published: July 2020

Application of biochar together with fertilizer is a promising strategy to minimize the loss of nutrient through surface runoff and leaching from agricultural field. Biochar has high surface area and can retain nutrients. Despite its advantages, low density of biochar leads to difficult in transporting, handling and mode of application. Our hypothesis is the densification of biochar with fertilizer could reduce transportation and handling costs and minimize loss of nutrient during soil application. Hence, the aim of this study was to determine the effects of mixture biochar-fertilizer with and without tableting on the soil chemical characteristics. There were four fertilization treatments including the control T1 (Soil), T2 (NPK), T3 (Biochar + NPK) and T4 (Biochar tablet embedded with NPK). Mineral clay soils were used and planted with maize. The soil chemical properties were determined for pH, electrical conductivity, total nitrogen, available phosphorus, exchangeable potassium and cation exchange capacity after 53 days planting. The application of biochar tablet embedded fertilizer to soil shows the highest total nitrogen, cation exchange capacity and lower available phosphorus after 53 days planting. The results suggest that the biochar tablet embedded with fertilizer is more efficient to minimize the losses of nutrients in soil.
Proposed Scheme of TCP-Friendly Rate Control (TFRC) for Real-Time Data Application
Authors: Izril Ishak Mohamad , Mahani Abdullah Wan , Maulid Ahmad Ainul , Bi Lynn Ong
Published: July 2020

This project proposes a scheme of TCP-Friendly Rate Control (TFRC) for transmitting real-time data application. Traditionally, real-time data transmission has been accomplished over the user datagram protocol (UDP). The challenging issues of using Transport Control Protocol (TCP) are restrictive bandwidth and lagging. Additionally, it is widely known that TCP is ill-suited to real-time multimedia streaming application. Having known these issues, this project aims to study the possibilities for improvement of real-time data application using TFRC which is designed for long-lived streams. As known, there are many advantages of TFRC, which are congestion control and guaranteeing the required throughput. Therefore, this project explores and proposes the advantages of TFRC in transmitting and receiving real-time data. It is proposed that the investigation of TFRC in real-time data is conducted using simulation technique. During the simulation, the developed model is representing the real-time application for analyzing the performance of modified TFRC. The modified TFRC mechanism is introduced as TFRC proposed scheme and evaluated through the simulation experiment. The simulation study of this project is to analyze and evaluate some parameters of existing TFRC mechanisms. The performance analysis and simulation experiment show that the proposed scheme performs better compared to the other mechanisms involved. Finally, this study has possibilities of the ongoing work to be carried for implementing in wireless environment and IPv6.
Relay Sensors Selection in Wireless Communication: Bit Error Rate Analysis
Authors: Abdulmohsin Hammood Dalal , Alkhayyat Ahmed
Published: July 2020

Cooperative communication system, which make use of the intermediate relays between the transmitter and the receiver, have been employed as an effective technique to combat the channel fading and to enhance system performance. Cooperative systems have some drawbacks such as high latency and diversity order not guaranteed. To alleviate the negative effects of these factors, relay selection protocol is employed in cooperative communication systems to increase overall cooperative system performance. Relay selection in the cooperative systems enables the source to cooperate with the single relay node rather than multiple relay nodes which guaranteed the diversity order.
Defining and Developing Measures of Lean Sustainability for Manufacturing Sector
Authors: Azim Azuan Osman , Abdul Aziz Othman , Rahim Mohd Kamarul Irwan Abdul
Published: July 2020

Toyota Manufacturing Company revival after World War II and its survival during 1973 global oil crisis had inspired many manufacturing organisations around the world to initiate lean transformation. However, due to lack of clear understanding of the lean sustainability concept, many manufacturers are unable to fully transform into a true lean organisation like Toyota. In fact, without a proper measurement, the organisation’s transformation progress will be unknown and the specific gains made from lean improvement cannot be monitored. Hence, it will result in wrong strategy deployment in the lean transformation program. This paper therefore aims to theoretically define Lean Transformation Sustainability and propose set of indicators for measuring this concept. A myriad of literature related to theory and practices of lean manufacturing was studied to better understand this concept. The methodology adopted to better understand Lean Transformation Sustainability concept was based on steps to success in writing literature review by Machi and McEvoy. Apparently, Lean Transformation Sustainability can be measured in three dimensions; (1) lean elements momentum, (2) lean culture adaptation, and (3) enduring success. At the end of this article, the authors recommend several opportunities for future research that can be used for adding literature to lean body of knowledge.
Influence of Filler Loading and in Situ Salicylic Acid Treatment on Corn Husk Fiber Filled Poly(Hydroxybutyrate-Co-Valerate)
Authors: Nuraqmar Syed Mahamud Syarifah , Hikmah Abdullah Nurul , Hanif Mohd Pisal Mohd
Published: July 2020

The effect of filler loading and in situ salicylic acid treatment on the mechanical properties and morphology of poly(hydroxybutyrate-co-valerate)/corn husk fiber (PHBV/CHF) biocomposites was studied. Both untreated and salicylic acid treated PHBV/CHF biocomposites were prepared by using heated two roll mill followed by compression moulding. It was found that the addition of CHF to PHBV biocomposites increased the tensile strength and Young’s modulus while the elongation at break decreased. Salicylic acid treated PHBV/CHF biocomposite display superior tensile strength and Young’s modulus than untreated PHBV/CHF biocomposite due to the enhanced filler–matrix interaction. The better interfacial adhesion between CHF and PHBV matrix was confirmed through scanning electron microscope (SEM) analysis.
Design and Development of Two-stage Low-noise Amplifier (LNA) using E-pHEMT Technology for C-band Application
Authors: Kamsaini Faaiqah , Shahrazel Razalli Mohammad , Zuraidah Ibrahim Siti , Zaizu Ilyas Mohd
Published: July 2020

The low-noise amplifier (LNA) is a vital part of the radio frequency (RF) transceiver system. It amplifies weak signals with minimal distortion. The LNA performance is mainly determined by its noise figure (NF), gain, and power consumption. In this paper, the design of a 6 GHz low-noise amplifier (LNA) using enhancement-mode pseudomorphic high-electron-mobility transistor (E-pHEMT) technology is presented. In order to attain high gain with low S-parameters losses, a two-stage LNA configuration with single-stub matching is devised. The same bias conditions are applied to both of the LNA stages, V
DS = 2.7 V and I
DS = 10 mA. The LNA design is simulated and optimised by using electromagnetic (EM) software. To further improve the overall LNA performances, high impedance inductors and series resonators are implemented into the circuit. Simulated results of the designed LNA indicate a power gain, S
21 of 25.2 dB and NF of 2.4 dB at 6 GHz with 27 mW dissipation per stage. The circuit layout is fulfilled with an E-pHEMT technology (ATF-55143) on the FR4 substrate. The LNA is powered by a 3 V DC power supply.
A Review of Geopolymer Based Metakaolin Membrane as an Effective Adsorbent for Waste Water Treatment.
Authors: Ibrahim Masdiyana , Mastura Wan Ibrahim Wan , Mustafa Al Bakri Abdullah Mohd , Syauqi Sauffi Ahmad
Published: July 2020

Geopolymer-based products help eco-accommodating sources of materials such as metakaolin, slag or fly ash. This review explores the blend configuration to generate geopolymer-based metakaolin membrane metakaolin and to evaluate the impact of a range of geopolymer-based metakaolin sintering temperatures at a temperature of 50 °C, 60 °C, 70 °C and 80 °C. As the quick development of a modern culture contributes to a large increase in interest in water, adsorption is taken closer to examined waste water extraction of the adsorption and repulsion of a metakaolin membrane geopolymer. Membrane waste water treatment is chosen to explore simple and inorganic membrane preparation techniques that have long help lives and low production costs. Reviews for geopolymer-based metakaolin membrane were therefore synthesized via a suspension that depends on the quick solidification method of high temperature suspension geopolymer slurries that were used as an adsorbent for treating waste water. Porous geopolymeric spheres have developed a homogenous structure with the aid of electron microscopy and Brunauer Emmett Teller (BET) investigations.Since permeable materials are regularly adsorbents, this examination has analyzed the adsorption by membrane geopolymers of heavy metals. This finding will advance the formation of improved wastewater treatment systems and along these lines give an elective answer for ecological harm brought about by substantial metal contaminations. Along these lines, molar (SiO2/Na2O) ratio of metakaolin and sodium silicate are fundamental in assembling a sort of geopolymer-based inorganic membrane which does not require a high temperature sintering process. Adsorption and dismissal consolidated can be utilized for wastewater auxiliary electrical plating forms not exclusively to proficiently wipe out center and low groupings of overwhelming metals in wastewater yet in addition to wipe out little sub-atomic contaminants in wastewater.
Image Segmentation using k-means Clustering and Otsu’s Thresholding with Classification Method for Human Intestinal Parasites
Authors: Ayunie Ahmad Khairudin Norhanis , Shamimi Rohaizad Nurfatin , Salihah Abdul Nasir Aimi , Chee Chin Lim , Jaafar Haryati , Mohamed Zeehaida
Published: July 2020

Helminth is one of the intestinal parasites that may cause harm and death to human. It is very important to have a system that is capable of assisting the technologist in investigating of fecal samples. In this paper, an automatic classification process is proposed to detect the different types of helminth eggs from fecal samples by using image processing technique. 50 samples of Ascaris Lumbricoides Ova (ALO) and Trichuris Trichiura Ova (TTO) are tested. First, these images undergo partial contrast stretching (PCS) technique to enhance the target images. Next, RGB and HSV color model have been compared in order to identify which color component is able to ease the segmentation process. S component shows a good results with high contrast between the target and the unwanted region. Then, Otsu’s thresholding and k-means clustering are compared in order to to select the most suitable image processing method to be used in classification procedure. k-means clustering shows a better results compared to Otsu’s thresholding. In classification process, area and size have been chosen as the feature to extract for the classification. The ratio for successfully detected ALO species is 84% while TTO is 76%.
The effect of the GNP-SDS loadings on the properties of the NRL/GNP-SDS composites
Authors: Che W.M. , Teh P.L. , Jalilah A.J. , Yeoh C.K.
Published: July 2020

Stretchable conductive polymer composites (CPC) are fabricated by incorporating the conductive particles into the polymer matrix. In this paper, CPC was fabricated by incorporating the sodium dodecyl sulfate (SDS) modified graphene nanoplatelet (GNP) into natural rubber latex (NRL) by varying loading from 0phr to 9phr using a simple mechanical stirring method. The effect of the GNP-SDS loadings on the properties of the composites were study by investigated the crosslink density, tensile properties, morphology of the tensile fracture surface and electrical conductivity. The crosslink density of the composites shows a decreased trend. Then, due to the well dispersed GNP-SDS, the tensile strength increased but decreased at high filler loading caused by the agglomeration issue. The tensile modulus also increased with increasing filler loading due to the intrinsic high modulus of GNP and the reduction of chain mobility. However, the electrical properties of the composites improved as GNP-SDS loading increased and achieved a percolation threshold at 7phr.
Printing Parameter Optimization of Biodegradable PLA Stent Strut Thickness by using Response Surface Methodology (RSM)
Authors: Asyraf Azli Amirul , Muhammad Noorhafiza , Mustafa Abdullah Albakri Mohd , Fathullah Ghazali Mohd , Zamree Abd Rahim Shayfull , Andrei Victor Sandu
Published: July 2020

This work presents printing parameter optimization of 3D printed biodegradable PLA stent. This study is motivated by a gap in current knowledge in 3D printing of stents identified in an extensive literature review. With the demand of coronary artery stents rising every year, the stent production demands a higher quality, lower cost, faster and economical process. Due to its availability relatively low-cost price and adaptability, PLA has been identified for an ideal material for biodegradable stents. Previously, laser micromachining was widely used for processing coronary stent. The emerging of 3D printing process has gained attention for its low cost, high reliability, simple operation and flexibility has shown potential as promising solutions in stents fabrication. The use of 3D printing for stent manufacturing purpose is newly emerge and not widely reported. Up to now, less research has been conducted on 3D printed PLA coronary artery stents. This work therefore, aims to study the relationship of the 3D printing processing parameter towards stents quality. Strut thickness become the key aspects in stents manufacturing. Processing parameter optimization was performed by using Response Surface Methodology (RSM). Nozzle temperature and printing speed were both effecting the strut thickness formations regardless of printing orientations.
The Dielectric Characterization of Tapioca Starch – Ha Tissue Scaffold
Authors: Fazli Mohd Nasir Nashrul , Ee Meng Cheng , Jamal Nurathirah , Riza Mohd Roslan Mohd , Aerina Fitri Mohd Hoři Nur , Chong You Beh , Jusoh Muzammil , Azizan Mokhzaini , Zakimi Zakaria Mohd , Farid Abdul Khalid Mohd
Published: July 2020

Tapioca starch-hydroxyapatite (HA) composites scaffold was fabricated using solvent casting and particulate leaching. The solvent casting involved the casting of polymer while particulate leaching involved the removal of porogen agent. The percentage of tapioca starch used were 50%, 60%, 70%, 80% and 90%, with the percentages of hydroxyapatite (HA) were set as 50%, 40%, 30%, 20% and 10% respectively. Here, sodium chloride was used as a porogen agent. SEM analysis was conducted to determine the micro structural of the scaffold surface. Based on the results, the pore size of composite scaffold is between ranges of 198 µm to 786 µm. For the dielectric study, the dielectric constants (D’) and dielectric loss factor (D”) over frequency range from 12.4 GHz to 18.0 GHz were obtained by transmission line method. Based on the result, both dielectric constant (s’) and dielectric loss factor (s”) was declined with the increment of the frequency.
Dielectric Properties Measurement and pH Analysis for Drinking Water
Authors: Fwen Hoon Wee , Been Seok Yew , Ping Jack Soh , Yeng Seng Lee , Oon Keng Lee
Published: July 2020

Every material has its own dielectric properties and it is also the same for water. In this research, dielectric properties measurement on water will be done to examine the water quality of drinking water whether it is safe to drink or not. Water quality in Malaysia, as well as access to water in general, is a major problem. The primary pollutants present in the water are oils, rubbish, suspended solids, sewage and toxic substances. These are consequences of untreated or only partially treated sewage caused by human activities. Thus, water quality in Malaysia is currently of some concern. The normal drinking water pH range mentioned in World Health Organization (WHO) and National Drinking Water Quality Standards (NDWQS) guidelines is between 6.5 and 8.5. The water may contain some residue even though the pH is in the range of 6 to 7.5 so it does not prove that the water is safe enough for drinking purpose. Thereby, the analysis about the water quality using the specific measuring instruments need to carry out to prove that the water in neutral pH may not be safe to drink as the pH does not prove the content of the water as clearly as dielectric properties. High Temperature Coaxial Probe as the dielectric properties measurement sensor will be used to provide better information compare to pH. The measurement parameters that had been used to determine the water quality is the dielectric constant. The results obtained from both pH and dielectric properties measurement values are been analyzed and compared and it shows that pH value for clean and contaminated water is at almost similar values while dielectric properties results show different for both clean and contaminated water.
Potential of Syntesized Silica Nanoparticles (Si-NPs) using Corn Cob for Arsenic Heavy Metal Removal
Authors: Balasubramaniam Thanaseelan , Bakar A.H.A , Uda M.N.A. , Hashim Uda , Parmin N.A. , Anuar Aminudin , Bakar M.A.A. , Afnan Uda M.N. , Sulaiman M.K
Published: July 2020

According to recent studies, millions of people are suffering from Arsenic (As) toxicity contamination. Arsenic is one of the most toxic and carcinogenic chemical elements and its contamination in paddy field has become a chronic problem. In the agricultural sector, arsenic-contaminated water irrigation has a higher level of arsenic contamination on the top soil, which can affect the quality of crop production such as rice plants. Rice plant requires a considerable amount of water to complete its lifecycle. In Asean countries like Malaysia, Indonesia and Thailand, Arsenic intake from rice is significantly higher, as rice plants have a special ability to take up arsenic from the soil and water used for irrigation. The transfer of arsenic from soil to plant systems is a serious issue that leads to considerable human exposure. Nanotechnology application plays vital role for any field work and research. In this research, the implementation of nanotechnology approach such as silica nanoparticles are able to remove the Arsenic heavy metal contamination. This paper focused on arsenic heavy metal removal using silica nanoparticles analaysed using spectrophotometric method.
The Effect of Multi-staged Swirling Fluidized Bed on Air Flow Distribution
Authors: Nawi M. A. M. , Ikman Ishak Muhammad , Rosli M. U. , Musfirah Musa Nur , Nor Azreen Ahmad Termizi Siti , Khor C. Y. , Faris M. A.
Published: July 2020

Fluidization is characterized as an activity that transforms fine solids into a liquid-state via contact with either a gas or a liquid. Currently, Swirling Fluidized Bed (SFB) is one of the new system that contribute on flow mixing to the beds due to the gas source which impart on the solid particles. Further the fluidized beds system are used mostly in the chemical process industry, mineral processing, processes energy and etc. Based on the current fluidized bed system there are still lacking in reducing high pressure drop and keep the energy consumption at high efficient condition. Due to this tips, the conceptual design of a multi-stages SFB was proposed to improve fluidization quality and minimize elutriation at the same time without requiring any extra facilities. By using the simulation method (Ansys Fluent) the behavior of velocity component via selected configuration of fix blades number (30) and through to variant of blade horizontal inclination angle (10°, 12° & 15°) the multi-stage SFB will be investigate. Aims of this study is to identify the air flow behavior at first and second stage blade distributor. Therefore, effect with less blades number in producing on high uniformity velocity would be acquired. The present study has found that by using blade inclination angle of 10° the high velocity magnitude (more than 60 m/s) at two different level of stage distributor can be reached. Moreover, it clearly be seen at blade inclination angle, 15° the velocity uniformity was sustain at certain width and less superficial velocity value occurred compared to other configurations.
Non-Oriented Electrical Steel Sheet: The Magnetic Properties Losses on Thickness Lamination Using Epstein Tester Frame
Authors: Binti Yahya Yanawati , Khairil Rahmat Mohd , Shariffuddin N. S.
Published: July 2020

Reducing lamination thickness of steel sheets can reduce the overall loss especially in core loss and copper loss. These research paper shows the impact of lamination thickness on the voltage induced of power loss for the Non-Oriented Electrical Steel Sheet. This study was conducted by using Epstein test which is an outflow of flux investigated throughout the measurement of power loss at corner and limb likewise for each thickness. This data shows and is presented based on different frequency such as 45 Hz, 50 Hz and 55 Hz. It indicates that 0.50 mm lamination thickness has a lot of losses instead of 0.35 mm.
Application of images from UAV to create cadastral map in Mekong Delta (VietNam)
Authors: Anh Tai Nguyen , Huu Si Dao , The Thiem Nguyen
Published: July 2020

Research topic: “Application of images from UAV (Unmanned Aerial Vehicle) to create a 1: 2000 cadastral map in Hoa Khanh Tay commune - Duc Hoa district - Long An province”. The project was conducted in Hoa Khanh Tay commune, Duc Hoa district, Long An province from August 2017 to December 2018 with the goal of testing the establishment of 1: 2000 cadastral map from UAV images, with Trimble UX5 HP aircraft and SONY a7R camera; The purpose of the paper is to assess the accuracy when using digital images taken from UAV to create large scale cadastral maps for state management of land. The project carried out through steps: designing flight imagegraphy, measuring grid control coordinates by static GPS technology, processing images, digitizing, drawing pictures, surveying information and additional measurements by total stationary method in the field, editing and perfecting the cadastral map according to current regulations. Based on the results of the project: evaluation of the accuracy and applicability of UAV images in mapping.