bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental study on heat transfer characteristics of annular flow between vertical concentric pipe
Authors: Tao Z.Y. , Jia G.S. , Meng X.Z. , Zhang L.Y. , Chai J.C. , Jin L.W. 
Published: July 2019

Abstract
Concentric pipe heat exchangers have been utilized extensively in practical project, such as petroleum, chemical, geothermal energy utilization and other fields. The study of annular flow between vertical concentric pipes is dominated by boiling heat transfer, while the study of forced convection heat transfer for single-phase flow is scarce. In this paper, an experimental investigation is carried out to study of the flow and heat transfer characteristics of the annular flow between vertical concentric pipes. The annular in a vertical concentric pipe heat exchanger with 25mm ring gap is tested with different volume flow rates and different constant heat flow densities. The results show that the Nusselt number of annular flow between vertical concentric pipes increases with Reynolds number. The local convective heat transfer coefficients reduce with the distance from the top to the bottom, which lead to a gradually increased trend in the fluid temperature along the flow direction. Based on the experimental data, an empirical equation of the Nusselt number is obtained to evaluate the overall heat transfer performance of vertically concentric pipe heat exchangers.
Low Cost Light Fidelity (Li-Fi) System Employing On-Off Keying Data Modulation in Half-Duplex Asynchronous Transmission Mode
Authors: Gheng Tuck Yong , Chee Yong Lau 
Published: July 2019

Abstract
In recent years, Light Fidelity (LiFi) technology has gained more and more attention due to its ability to transmit large data in a short time, and prevents interference and radiation compared to conventional WiFi communication. Therefore, it is more preferable to be employed in health care related sector. In this paper, a low cost wireless data communication using Li-Fi Technology is presented. This project employed On-Off Keying (OOK) Modulation Technique to encode and decode messages. A pair of prototype transceivers were developed and adapting Half-Duplex Asynchronous Transmission Mode. The overall hardware is employing Arduino Nano and LEDs and hence the price was kept around USD 25. The entire system was being tested on four different aspects and they were data transmission duration, distance between transceivers, the transmission angle of the transceivers and the message capacity. These tests were being evaluated by Word Error Rate (WER) to acquire the accuracy. In short, the transceivers were able to transmit and receive all the alphabets, numbers and symbols on the ASCII computer keyboard. It works optimally with the transceiver angle of ±10° in a distance of 20cm with the minimum delay of 102ms. The data modulation techniques and the hardware selection were believed as the factors to improve the system performance.
Mechanical and Structural Comparison of AZ31 and AZ61 Magnesium Alloys Along with Deep Drawing Capabilities
Authors: Akhtar Maaz , Saeed Atif , Mehdi Murtuza 
Published: July 2019

AbstractIn the world of advance development, rapid growth for any nation, country or individual is a must thing to have. There are several studies and researches that have put forward to us, not only revolutionized the human society but also helped us to live a better life in a better way. This study focusses on a similar track to analyze the characteristics of magnesium alloys; known for its high weight to strength ratio, so that it could replace; at time; extensively used materials i.e. steel and aluminum. The magnesium alloy has several advantages over steel and aluminum i.e. due to its low density, its weight is quite low, which is the reason that it is extensively used in aerospace and outer space application. Studies suggests that Low weight allows system to consume lesser fuel as compare to the normal ones. Along with it, inspite of having lesser density it doesn’t compromises its mechanical strength and provide high weight to strength ratio; which makes it more suitable for structural and automotive applications. However, inspite of having such tremendous advantages, there are some drawbacks which leads to its minimum usage as compare to both the materials. Magnesium alloys have low ductility, however, it can be enhanced to certain level by several methods to make it cope with real world industrial, commercial and residential applications. This study focusses on analyzing the mechanical and structural characteristics of two grades of magnesium alloy i.e. AZ31 and AZ61. The conclusion has been made by carrying out different mechanical tests i.e. tensile testing, Brinell hardness testing, torsion testing and cupping testing. After conducting these tests this was concluded that AZ31 and AZ61 are a good replacement for aluminium as it has a poison’s ration of 0.4 and 0.24 respectively.
Development of analytical solution for thermo-mechanical stresses of multi-layered hollow cylinder for the application of underground hydrogen storage
Authors: Sim L C , Yeo W H , Pubolaksono J , Saw L H , Tey J Y , Ting C H 
Published: July 2019

Abstract
Hydrogen fuel has been playing an important role nowadays, it is considered as clean fuel and the hydrogen element is highly abundant. Storage of hydrogen in geological formations has been widely applied particularly for large-scale energy storage that required to meet high energy demand. There are different types of underground hydrogen storage methods, one of the most popular and reliable method is to store the hydrogen in depleted oil and gas wells. The structure of the depleted oil and gas well usually constructed by several layers of different materials such as formations, cement and casing. To ensure the well integrity is maintained, a reliable analytical solution to estimate the development of stress under pressure and thermal loading is required. In this paper, a more effective method to estimate the thermo-mechanical stresses of multi-layered hollow cylinder well is developed. The analytical solution is established by considering the well as generalized plane strain problem. The derivation of the equations and the algorithm to obtain results for four layered gas well were demonstrated. In general, the results obtained from the proposed analytical solution are well in agreement with the numerical results. The variations of results obtained from analytical solution and numerical solution are only less than 0.1%.
Solar Distillation Thermoelectric Power Generation
Authors: Remeli M F , Singh B , Amirah N , Meon M S , Fadilla W N 
Published: July 2019

Abstract
In this paper, a phase change material (PCM) heat storage and thermoelectric cells were integrated into a solar still. This project aim is to store the available solar heat using the PCM for generating power and increasing freshwater production. An experimental test rig of the solar still was designed, built and tested. The solar still consists of a single slope basin container with a PCM storage located at the bottom. The thermoelectric cells were installed beneath the PCM storage. The natural convection cooling method was used to cool the thermoelectric cells. The study showed that the solar still thermoelectric power generation (SSTEG) was able to produce 9.6 ml/m2 of fresh water and at the same time generated peak open circuit voltage of 44mV. The study is hopefully could provide a simple and cheap solar still system that can solve the water and electricity problem in rural areas.
Performance Analysis of a Solar Desalination System with Concentrated Solar Power (CSP)
Authors: Yong Ho Zhi , Bahar Rubina 
Published: July 2019

Abstract
Malaysia, being located around the tropical belt, enjoys ample solar exposure throughout the year. Harnessing solar energy for different application is making progress nationwide. Besides extending research on photovoltaic cells; the solar water heating for different purposes is progressing through the past decades. In this paper, performance of a solar still associated with concentrated solar power facilities is presented. In a typical solar still, the solar heat is used to evaporate waste/brackish/saline water (generally termed as feedwater). A basin of the feedwater covered by an inclined transparent cover is placed under the sun to trap the solar heat. The solar heat evaporates the feedwater and the condensate is collected from the inner surface of the transparent cover. In this study, the incident solar irradiation is optimized to produce freshwater from saline/brackish water in a portable solar collector with concentrated solar power (CSP). Fresnel lens has been used as the CSP apparatus. A flat Fresnel lens of size 400 mm x 300 mm with a focal length of 510 mm and light intensity of 92% was attached to concentrate the incident solar irradiation on the inclined transparent cover. Preliminary experiments showed that addition of the Fresnel lens with an optimum tilt of 45° created a “hotspot” in the basin in a particular time of the day and the average condensate production rate increased by 92% compared to that from a bare transparent cover. The distillate from the solar still had a conductivity of 39 μS (25 ppm) which is well below the range of drinking water standard (500 ppm) of the World Health Organization. This study has been conducted in Kajang, Malaysia during the month of August 2018 with an average daytime temperature of 32°C.
Development of Rainwater Harvesting System for Sekolah Menengah Kebangsaan Iskandar Syah Melaka
Authors: Halim ZA , Din AT , Tokit EM , Rosli MAM 
Published: July 2019

Abstract
This paper presents the development of rainwater harvesting (RWH) system at Sekolah Menengah Kebangsaan Iskandar Syah (SMKIS), Melaka to promote landscape sustainability. The proposed RWH system deployed an elevated tank, a sequential filter, and a storage tank. A fertigation pond and a turbine were installed as part of the RWH system in Taman Herba to promote an ecosystem for freshwater habitat and to generate energy. The RWH system was used as an alternative water supply to the Taman Herba and the fertigation pond as well as water supply for power generation. It was found that the RWH system has successfully reduced the rainwater flowrate in the existing drainage system by 50.9% and effectively reduced the utility bills for the landscape irrigation and the fertigation pond. The turbine generated 26.6 W power which is adequate to light up a scrolling message board at Taman Herba. Both the fertigation pond and the turbine embellished the Taman Herba landscape and are a good platform for experiential learning for the secondary students in SMKIS.
Cleaner production and sustainability: stakeholder pressure and the adoption of pollution prevention measures of industrial hazardous waste in Malaysia
Authors: AuYong HN , Chin YH 
Published: July 2019

Abstract
In Malaysia, related environment laws to comply is mainly Environmental Quality Act 1974. The Cradle to Cradle concept is practiced, where recycling and recovery are considered useful resources. The scheduled waste recycling companies are mostly located in Selangor, Pulau Pinang and Johor. Majority of the license issued is of the type of electronics waste. Regulated industries are expected to implement the environmental safety and health management programme to maintain their competitive edge. Hazard control actions are such as scheduled waste control and emission control. Safety management programmes must be integrated into the company daily activities. Workplace hazard is mandatory to be communicated to those who work with the risk. The employees must be trained to handle hazardous waste. Companies have to prepare emergency and crisis management against potential hazardous waste emergencies. Consequently, the benefits gained through improvement with technological investment offset are the main drivers for environmental management programme. In other words, this programme can improve the environmental aspects and performance using industrial engineering, improve natural resource efficiency, reduce energy costs as well as the costs of handling and disposing of hazardous waste, reuse alternative materials and reduce release of pollutants by recycling of waste. This study looks into the quantity of hazardous waste generated, as well as DOE court cases. The study shows the increasing trend of environmental protection expenditure especially on waste management, even though the chemical industry is generating lesser scheduled waste. DOE court cases are mainly related to licensing and water pollution. Many companies engage the services of scheduled waste facilities are located in Selangor, Johor and Pulau Pinang, though Cenviro operates the first integrated hazardous waste management centre in Malaysia. With the positive relationship between environmental performance and environmental care, the higher level of environmental performance achieved, the better will become the environmental quality. Environment performance of the manufacturing sector could be further improved by promoting environmental management programmes.
Utilization of bottom ash for degraded soil improvement for sustainable technology
Authors: Trung Phan Nghia , Sengsingkham Thidphavanh , Tiyayon Pimsiri , Maneeintr Kreangkrai 
Published: July 2019

Abstract
Bottom ash is one of the main products from coal combustion in coal-fired power plants. It has been applied in many applications such as landfill, cement industry or raw feed for clinker, concrete, etc. Furthermore, it can be used in agriculture to improve soil quality. However, the utilization rate of bottom ash in agriculture is still very low only 0.1% of bottom ash. The properties of bottom ash can adjust the pH in soil and provide some nutrients to improve soil quality. Moreover, the soil degradation is a major problem in agricultural countries. The soil degradation is the decline in soil quality due to the improper land use, agriculture with misuse or excess use of fertilizers and so on. In Thailand, the soil degradation is a serious problem in agriculture in the northern mountainous areas. The mainly causes of soil degradation are from human activities such as overuse of pesticide, herbicide, and fertilizer, deforestation, expansion of cultivated areas. Therefore, the objective of this research is to apply the bottom ash from Mae-Moh power plant to improve soil quality of degraded soil in Nan province, Thailand and to investigate the effects of amount of bottom ash from 0-30% by weight on some parameters such as pH, electrical conductivity (EC), bulk density and soil texture. From the result, it is clear that with higher amount of bottom ash, the quality of degraded soil has been improved especially pH and soil texture. The pH can increase from 5.664 up to 7.408. Soil texture can change from clay to loam or sandy loam. The bulk density of soil decreases at all rates of bottom ash which is favorable for plant growth. This research can be applied for soil amendment and is expected to improve the yield for plant growing. Furthermore, the practical combinations of 10% and 20% of bottom ash are considered to apply in the real field to evaluate the improvement on soil properties in the future.
Synthesis and Evaluation of Novel TiO2-based Self-cleaning Coating Layer for Buildings
Authors: Appasamy J S , Kurnia J C 
Published: July 2019

Abstract
This research was carried out in order to analyse the potential of novel nitrogen-doped TiO2/SWCNT (N-doped TiO2/SWCNT) photocatalyst nanocomposites for pollutant removal that deposits on surfaces of buildings. In the present work, the procedure to fabricate this nanocomposite follows a simple method which is sol-gel synthesis method using titanium tetraisopropoxide (TTIP) and ammonia as the precursor. Different composition of TiO2 and SWCNT were used to achieve the optimum composition suitable for building surfaces as a self-cleaning coating. The fabricated dried sols were characterized by XRD to ensure TiO2’s anatase nanocrystalline structure was maintained even after doping. The morphology of these novel coatings was observed by FESEM. FESEM showed that uniform dispersion between TiO2 and SWCNT is present which exhibited a vine-like structure. Methylene blue degradation test was conducted to measure the photocatalytic efficiency of each coating. The highest degradation efficiency achieved was 72.43 %. Spin-coating method was used to deposit a thin layer of this coating on the glass substrate to inspect the water contact angle (WCA) of the as-prepared coatings. The coatings displayed a contact angle of 21.3 °proving that the wetting characteristic falls under hydrophilic category in which any sprinkled water is able to remove the dirt that deposits on the surface. Self-cleaning testing was carried out on glass substrates to further evaluate the coating layers. The coated substrates cleaned about 99 % of the dirt that deposited on its surface. These coatings could be utilized in various applications be it indoors or outdoors, for water remediation, energy saving panels and many potential fields.
Wave velocity selection for leakage localization of water pipeline by Variational Mode Decomposition
Authors: Lee W T , Tan A C , Tey J Y , Rahman F A 
Published: July 2019

Abstract
Water pipelines are susceptible to leakage due to deterioration over time, pipe corrosion, water hammer and soil movement. Water leakage results in losses of revenue and can cause devastating consequence to the environment. Water leakage often happens below ground and remains undetected until a sizable crack has been developed on the pipeline. In the event of a leak, water from the pressurized pipeline expels through the crack at high velocity and generates acoustic waves which propagate along the pipeline. These waves can be picked up by acoustic emission (AE) sensors attached on the surface of the pipe without interfering with the operation of the pipeline. To pinpoint the location of a leak, it requires at least two sensors to be placed on each side of the leak along the pipe. The location of the leak can be located by knowing the time delay of arrival (TDOA) of the acoustic waves at both sensors by employing cross-correlation technique. Leak location is commonly calculated using a constant wave velocity which corresponds to the pipe material. However, the localization error is often large because acoustic wave does not travel along the pipeline at a fixed velocity due to wave dispersion phenomena. The velocity of the acoustic wave is dependent on the frequency and mode of the wave. This paper proposes a leak localization method with an innovative wave velocity selection method based on mode separation by Variational Mode Decomposition (VMD). The proposed method is validated by a leak simulation experiment and it achieves an accuracy of within 7.72% in leak localization.
Phosphoric Acid Doped Polybenzimidazole and Sulfonated Polyether Ether Ketone Composite Membrane for Hydrogen Production in High-Temperature Copper Chloride Electrolysis
Authors: Kamaroddin M F A , Sabli N , Abdullah T A T , Abdullah L C , Izhar S , Ripin A , Ahmad A 
Published: July 2019

Abstract
A composite membrane of polybenzimidazole (PBI) and sulfonated polyether ether ketone (SPEEK) based electrolyzer that operates at higher working temperature above 80 °C is advantageous for faster electrochemical kinetics, higher current exchange density and more resistance to fuel impurities. A high-temperature copper chloride-based composite membrane electrolysis is proposed to overcome the issue of fuel diffusivity, membrane’s thermal and mechanical stability in hydrogen production. The phosphoric acid (PA) functionalized composite PBI and SPEEK membranes were synthesized by a standard method followed with immersion in 85 wt% phosphoric acid at different temperatures for 80 minutes. The composite membranes have been characterized for water uptake, tensile strength, thermal stability by thermogravimetric (TGA) analysis, permeability by Cu diffusion cell and ionic exchange capacity (IEC). From the result, the PA doped PBI membrane (100 °C, 80 min) shows significant improvement in tensile strength (92.23 MPa) with PA doped PBI membrane (40 °C, 80 min) exhibited the lowest Cu diffusion at 5.56 x 10−8 cm2 s−1. The composite PBI/ZrP has the advantage of the most thermally stable membrane and excellent ionic exchange capacity at 3.20 x 10−3 mol g−1.
Mechanical and Fatigue Properties of Gravity Die-Cast A356 Aluminium Alloy with Addition of Scandium
Authors: Masita A , Yeo W H , Saw L H , Lim Y P , Lee J W , Ng T C 
Published: July 2019

Abstract
A356 is widely used for the casting of high strength components in automotive, aerospace and other industrial applications. This is due to its high achievable strength, castability, light weight, good thermal and electrical conductivity. However, the as-cast A356 exhibits relative poor mechanical properties due to the presence of coarse acicular eutectic silicon morphology. In this study, Sc-modified-A356 and the effect of heat treatment have been studied and compared with unmodified A356. Various amounts of Sc ranging from 0.2 wt% to 0.6 wt% were added into the mixture of A356 aluminium alloy and the specimens were produced by using gravity die-casting. Next, the ultimate tensile strength, Vickers hardness and fatigue behaviour of the cast samples are examined. The results revealed that by adding 0.4 wt.% of Sc, the heat treated sample is able to achieve ultimate tensile strength of above 300 MPa and Vicker’s hardness of 118 HV. Furthermore, the fatigue properties of the 0.4 wt% Sc-A356 with T6 heat treatment was found to be improved as compared to the unmodified A365 samples.
Experimental Study on the Performance of a Savonius-Darrius Counter-Rotating Vertical Axis Wind Turbine
Authors: Didane D H , Maksud S M , Zulkafli M F , Rosly N , Shamsudin S S , Khalid A 
Published: July 2019

Abstract
This paper describes the study of a small vertical axis wind turbine (VAWT) with a combined design of Darrius and Savonius counter-rotating rotors. The main purpose of this study is to improve the extraction capabilities of a single-rotor VAWT by using two distinct rotor designs while adopting the counter-rotating technique. Given that the conversion capabilities and operational speed of the existing wind turbines are still limited, the current technique is used to enhance the efficiency and expand the operating speed range of the VAWT. The Darrius and Savonius counter-rotating rotors were exposed to a similar upstream wind speed using a centrifugal blower. It was found that the Savonius-Darrius counter-rotating rotor was able to operate effectively particularly at the low-speed wind. By looking at the individual performance of the rotors, it was observed that the conversion efficiency of the H-type rotor increases as the wind speed increases. However, in the case of the S-type rotor, it is higher at lower wind speed and tends to decreases as the operating speed increases. Thus, the maximum efficiency of the S-type rotor was achieved at low-speed, whereas the H-type rotor has achieved its maximum efficiency at the highest operating wind speed. The average efficiency of the present Savonius-Darrius counter-rotating rotor has been improved to reach almost 42% more efficiency in terms of torque.