Setiawan A.,Malikussaleh University |
Kennedy E.M.,University of Newcastle |
Stockenhuber M.,University of Newcastle
Energy Technology | Year: 2017
Fugitive gas emissions from coal mining are widely known to be significant contributors to the emission of alkanes, mainly methane, to the environment. Utilization of coal-mine ventilation air methane (VAM) is a crucial mission to minimize methane emission in the atmosphere. This paper reviews current technology for mitigation and utilization of methane emissions from coal mining. Challenges and opportunities for each technology are discussed together with their benefits/disadvantages. Catalytic combustion technology is recommended as the best option due to the low and variable concentration of methane in coal-mine ventilation air, as well as its high volumetric flow. Herein, current developments in flameless combustion are discussed in detail with a few highlights on palladium-based catalyst development. The remaining uncertainties and obstacles in the development of palladium-based catalysts for VAM are also discussed. This paper highlights a few important practical aspects that necessitate further detailed investigation, such as catalyst deactivation phenomena, the stability of the catalyst under humid conditions, and the effect of coal dust on catalytic activity and stability. Notably, a pressure decrease, heat recovery/self-sustaining, and long-term deactivation are key for the successful development of VAM catalytic combustors. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Hendriana Y.,Ahmad Dahlan University |
Hardi R.,Malikussaleh University
2016 International Conference on Information Technology Systems and Innovation, ICITSI 2016 - Proceedings | Year: 2016
Remote control technology has been developed by utilizing various transmission media. Some of them are remote control by the media using infrared, radio, internet and telephone line. Remote control system via the telephone line has an advantage in terms of distance range and practicality compared to other media. The presence of mobile phone or mobile phone that has been known and used by many people, who are able to communicate wherever they are, without being limited by space and range of cable lengths could be a solution for the needs of remote objects as described above. One of the most popular mobile phone function is to send and receive SMS. SMS is suitable for the control system of wireless real time because the speed of data delivery, efficiency and breadth of coverage, but the excess mobile phone with SMS facility of its still needs to be connected to a control device to be able to control on / off devices electric remotely. © 2016 IEEE.
Maizuar M.,Malikussaleh University |
Zhang L.,University of Melbourne |
Miramini S.,University of Melbourne |
Mendis P.,University of Melbourne |
Thompson R.G.,University of Melbourne
Structural Control and Health Monitoring | Year: 2017
The process for assessing the condition of a bridge involves continuously monitoring changes to the material properties, support conditions, and system connectivity throughout its life cycle. It is known that the structural integrity of bridges can be monitored by measuring their vibration responses. However, the relationship between frequency changes and structural damage is still not fully understood. This study presents a bridge condition assessment framework which integrates computational modelling and noncontact radar sensor techniques (i.e., IBIS-S) to predict changes in the natural frequencies of a bridge girder as a result of a range of parameters that govern its structural performance (e.g., elastomeric bearing stiffness, concrete compressive stiffness, and crack propagation). Using a prestressed concrete bridge in Australia as a case study, the research outcomes suggest that vibration monitoring using IBIS-S is an efficient way for detecting the degradation of elastomeric bearing stiffness and shear crack propagation in the support areas that can significantly affect the overall structural integrity of a bridge structure. However, frequency measurements have limited capability for detecting the decrease in the material properties of a bridge girder. © 2017 John Wiley & Sons, Ltd.
Reza Mirzaei M.,Iranian Fisheries Research Organization |
Hwai A.T.S.,Universiti Sains Malaysia |
Khalil M.,Malikussaleh University
Journal of Shellfish Research | Year: 2017
A study was conducted on the relationship between the reproductive cycle and shell growth rate of Anadara granosa (Linnaeus, 1758). Gonadal maturity stages, increment width, and environmental factors were examined by means of a field enclosure experiment in Balik Pulau, Penang Island, Malaysia, from December 2011 to November 2012. Histological analysis of gonads showed that gametogenic activity of A. granosa occurred throughout the year, with maximum spawning activity observed from April 2012 to late June 2012 (15%-28%) in males and from March 2012 to late June 2012 (19%-44%) in females. Shell cross-section analysis showed that the increment widths of both sexes in the growing group (indeterminate and developing stages) and the spawning group (ripe and spawning stages) ranged from 35-57 to 8-17 μm, respectively. Seawater temperature and salinity recorded on a daily basis throughout the study period ranged from 22-33°C and 29-31, respectively. A comparison of increment width and gonad development stages in different environmental conditions showed that shell growth in the growing group decreased when seawater temperature and salinity decreased slightly. In contrast, increment widths in the spawning group were much narrower and were influenced by energy consumption during ripe and spawning stages. This study shows spawning breaks in shell structure are considered markers for identifying the period of sexual maturity. Therefore, spawning breaks are suitable proxies for interpretation of the temporal changes in shell microgrowth lines in terms of reproductive cycle of cockle and understanding the number of spawning periods throughout the year.
Khalil M.,Malikussaleh University |
Yasin Z.,Universiti Sains Malaysia |
Hwai T.S.,Universiti Sains Malaysia
Ocean Science Journal | Year: 2017
A study on the reproductive cycle of the blood cockle Anadara granosa (Bivalvia: Arcidae) was conducted at three different areas in the northern region of the Strait of Malacca. A total of 1,920 samples of adult A. granosa (38–71 mm length) were collected from June 2009 until September 2010. Qualitative techniques (gonadal microscopic fresh smear test and histology analysis) as well as quantitative techniques (analysis of condition index and gonadal index) were used to predict monthly gonadal development stages of A. granosa. The gonadal index of A. granosa from Banda Aceh (Indonesia) (r = 0.469, P > 0.05) and Pulau Pinang (Malaysia) (r = 0.123, P > 0.05) did not show any correlation to their condition index, whereas the gonadal index of A. granosa from Lhokseumawe (Indonesia) (r = 0.609, P < 0.05) showed moderate positive correlation to the condition index. During the 16 month sampling period, four reproductive cycles were observed: each from three to six months. The process of releasing gametes is termed dribble spawning, and is the same in all populations. The principle component analysis (PCA) indicated that A. granosa reproduction was affected by interaction between internal physiological factors and indigenous environmental factors. In all sampling areas, phytoplankton density played a key role in the reproductive cycle in A. granosa. Information on the reproductive biology of this species is essential for species management and to improve the sustainability practices of the fisheries industry. These findings will provide basic information on the biology of the blood cockle A. granosa for stock management in the region. © 2017 Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht
Ula M.,Malikussaleh University |
Fuadi W.,Malikussaleh University
Journal of Physics: Conference Series | Year: 2017
As modern banking increasingly relies on the internet and computer technologies to operate their businesses and market interactions, the threats and security breaches have highly increased in recent years. Insider and outsider attacks have caused global businesses lost trillions of Dollars a year. Therefore, that is a need for a proper framework to govern the information security in the banking system. The aim of this research is to propose and design an enhanced method to evaluate information security governance (ISG) implementation in banking environment. This research examines and compares the elements from the commonly used information security governance frameworks, standards and best practices. Their strength and weakness are considered in its approaches. The initial framework for governing the information security in banking system was constructed from document review. The framework was categorized into three levels which are Governance level, Managerial level, and technical level. The study further conducts an online survey for banking security professionals to get their professional judgment about the ISG most critical components and the importance for each ISG component that should be implemented in banking environment. Data from the survey was used to construct a mathematical model for ISG evaluation, component importance data used as weighting coefficient for the related component in the mathematical model. The research further develops a method for evaluating ISG implementation in banking based on the mathematical model. The proposed method was tested through real bank case study in an Indonesian local bank. The study evidently proves that the proposed method has sufficient coverage of ISG in banking environment and effectively evaluates the ISG implementation in banking environment. © Published under licence by IOP Publishing Ltd.
Sari R.,National University of Malaysia |
Yaakob Z.,National University of Malaysia |
Ismail M.,National University of Malaysia |
Daud W.R.W.,National University of Malaysia |
And 2 more authors.
Ceramics International | Year: 2013
In this work, the performance of a novel coating of palladium over an alumina ceramic membrane was studied to enhance the hydrogen selectivity produced by an ethanol steam reforming reaction. Preparation of the palladium coated ceramic alumina membrane tube was performed using a combined sol-gel process and an electroless plating technique. Characterisation of the membrane was conducted using SEM and AFM. The palladium-alumina membrane was housed in the module membrane, and then packed with CuO-ZnO commercial catalyst to carry out the ethanol steam reforming reaction in a solid-gas phase. The reaction temperature and H2O/ C2H5OH feed molar ratio of the feed reactants were maintained at 573 K and 13:1, respectively. The reactions were then conducted at various reaction pressures in the range of 1.08-1.38 bar and WHSV of either 37 or 74 h-1. Their effects upon ethanol conversion, hydrogen recovery, hydrogen yield and hydrogen selectivity were investigated. At 1.38 bar with WHSV 37 h-1, the maximum of ethanol conversion (61.5%), hydrogen recovery (42.82%), hydrogen yield (26.75%) and hydrogen selectivity (92.6%) have been measured. © 2012 Elsevier Ltd and Techna Group S.r.l.
Muhammad,University Putra Malaysia |
Muhammad,Malikussaleh University |
Choong T.S.Y.,University Putra Malaysia |
Chuah T.G.,University Putra Malaysia |
And 2 more authors.
Chemical Engineering Journal | Year: 2010
Mesoporous carbon coated monolith prepared from furfuryl alcohol by the dip-coating method was utilized as an adsorbent for adsorption of β-carotene from crude palm oil. The effect of temperature on the adsorption was investigated by batch adsorption experiments. The adsorption quantity increased with increasing temperature. The adsorption was performed using two different solvents, isopropyl alcohol and n-hexane. The maximum adsorption capacity of β-carotene was 62.118. mg/g for isopropyl alcohol at 50 °C. The experimental results were fitted using the Langmuir and Freundlich isotherms. The Langmuir described the adsorption process better. The negative values of Gibbs free energy change suggested that the adsorption was a spontaneous process. The positive values of heat of enthalpy and entropy change confirmed the endothermic nature of the adsorption. © 2010 Elsevier B.V.
Sofyan A.,Malikussaleh University
Procedia Engineering | Year: 2015
Environmental and operational variables and their impact on structural responses have been acknowledged as one of the most important challenges for the application of the ambient vibration-based damage identification in structures. The damage detection procedures may yield poor results, if the impacts of loading and environmental conditions of the structures are not considered. The reference-surface-based method, which is proposed in this paper, is addressed to overcome this problem. In the proposed method, meta-models are used to take into account significant effects of the environmental and operational variables. The use of the approximation models, allows the proposed method to simply handle multiple non-damaged variable effects simultaneously, which for other methods seems to be very complex. The inputs of the meta-model are the multiple non-damaged variables while the output is a damage indicator. The reference-surface-based method diminishes the effect of the non-damaged variables to the vibration based damage detection results. Hence, the structure condition that is assessed by using ambient vibration data at any time would be more reliable. Immediate reliable information regarding the structure condition is required to quickly respond to the event, by means to take necessary actions concerning the future use or further investigation of the structures, for instance shortly after extreme events such as earthquakes. The proposed damage identification method is applied to a numerical finite element model, which is a concrete filled beam bridge that is excited by an ICE train series. The train speed and ambient temperature are chosen as environmental and operational variables respectively. In addition to the natural frequencies, wavelet energy damage indicator is used. The results of the numerical study show that the proposed damage identification method is able to discriminate the damaged and undamaged scenarios of the bridge model. The results also show that the wavelet energy damage indicator is sensitive to small change of structure. However, it does not always have a monotonic trend with respect to damage severity. © 2015 The Authors. Published by Elsevier Ltd. Published by Elsevier Ltd.
Hosseini S.,University Putra Malaysia |
Choong T.S.Y.,University Putra Malaysia |
Hamid M.,University Putra Malaysia |
Hamid M.,Malikussaleh University
Desalination and Water Treatment | Year: 2012
A carbon-based honeycomb monolith was prepared using dip-coating method. The carbon-based monolith was then used to remove a cationic dye (methylene blue [MB]) from aqueous solution. Surface chemistry studies demonstrated that acidic functionality (0.567 mmol g -1) dominated as compared to basic functionality (0.019 mmol g -1). N2 adsorption/desorption revealed a mesoporous structure. The Brunauer-Emmett-Teller surface area was approximately 352 m-2 g -1 and the mesoporous volume devoted about 67% the total pore volume. The effects of different parameters (such as initial pH, initial dye concentration, temperature, and contact time) on MB removal were investigated in batch mode. The maximum adsorption capacity is around 121.3 mg g -1 at optimum pH = 10. An increase in adsorption capacity was observed via increasing MB concentration, with equilibration time ranged between 3,200 and 4,000 min. Both the Langmuir and the Redlich-Peterson models were found to describe well the equilibrium data. Kinetic studies showed better fitting for the pseudo-second-order model. The intraparticle diffusion model showed multilinearity, indicating two or more steps were involved to describe the adsorption process. Regeneration studies showed that the adsorption capacity of the adsorbent was reduced by about 20% after six cycles. © 2012 Desalination Publications. All rights reserved.