Journal of Engineering and Technological Sciences 2021-10-04T21:01:15+07:00 Prof.Dr. Tjandra Setiadi Open Journal Systems <p style="text-align: justify;"><img class="imgdesc" src="" alt="" /><p style="text-align: justify;"><em>Journal of Engineering and Technological Sciences</em> welcomes full research articles in the area of Engineering Sciences from the following subject areas: Aerospace Engineering, Biotechnology, Chemical Engineering, Civil Engineering, Electrical Engineering, Engineering Physics, Environmental Engineering, Industrial Engineering, Information Engineering, Mechanical Engineering, Material Science and Engineering, Manufacturing Processes, Microelectronics, Mining Engineering, Petroleum Engineering, and other application of physical, biological, chemical and mathematical sciences in engineering. Authors are invited to submit articles that have not been published previously and are not under consideration elsewhere.</p><p style="text-align: justify;">Starting from Vol. 35, No. 1, 2003, full articles published are available online at, and indexed by <a href=";tip=sid&amp;clean=0">Scopus (2020:Q3)</a>, <a href=",p24780957,3.html">Index Copernicus</a>, <a href=";hl=id">Google Scholar</a>, <a href="">DOAJ</a>, <a title="Journal of Engineering and Technological Sciences" href=";tip=sid&amp;clean=0" target="_blank" rel="noopener">The Elektronische Zeitschriftenbibliothek EZB by University Library of Regensburg</a>, <a href=";Find=Journal+of+Engineering+and+Technological+Sciences&amp;SearchType=Contains">EBSCO Open Science Directory</a>, <a href="">Ei Compendex</a>, Chemical Abstract Service (CAS), <a href="">Zurich Open Repository and Archive Journal Database</a>, <a href=";Full=*journal%20of%20engineering%20and%20technological%20sciences">Emerging Sources Citation Index</a> and <a href=";mod=viewjournal&amp;journal=7390">Indonesian Publication Index.</a></p><p style="text-align: justify;">The journal has been also accredited for five years based on The Decree of Directorate General of Research and Development Strengthening, Ministry of Research, Technology and Higher Education of the Republic of Indonesia No. 30/E/KPT/2018, for Volume 50 No.1, 2018 until Volume 54 No. 6, 2022.</p><p>ISSN: <a href="">2337-5779</a>, E-ISSN: <a href="">2338-5502</a></p><p style="text-align: justify;">Published by the Institute for Research and Community Services, Institut Teknologi Bandung, in collaboration with <a href="">Indonesian Engineering Association (<em>Persatuan Insinyur Indonesia-PII</em>).</a></p><span style="text-decoration: underline;"><strong>Publication History</strong></span><p><strong>Formerly known as:</strong></p><ul><li>ITB Journal of Engineering Science (2007 - 2012)</li><li>Proceedings ITB on Engineering Science (2003 - 2007)</li><li>Proceedings ITB (1961 - 2002)</li></ul><p>Back issues can be read online at: <a href=""></a></p><p><span style="text-decoration: underline;"><strong>Scimago Journal Ranking</strong></span></p><a title="SCImago Journal &amp; Country Rank" href=";tip=sid&amp;exact=no"><img src=";title=true" alt="SCImago Journal &amp; Country Rank" border="0" /></a><p> Metal-supported SOFC Fabricated by Tape Casting and Its Characterization: A Study of the Co-sintering Process 2021-08-13T10:34:42+07:00 Zaka Ruhma Keiji Yashiro Itaru Oikawa Hitoshi Takamura ‪Tatsuya Kawada <p class="Abstract">Metal-supported SOFC consists of metallic and ceramic multilayers. Since the cell has to be flat, interaction between the layers that results in a flat sintered layer needs to be studied. The method used here was changing the starting materials through several experiments. Here, we highlight the effects of pore former in metal slurry on the sintered half-cell multilayer of a 430L metallic support, an NiO-8YSZ anode, and an 8YSZ electrolyte. The results show that by changing the amount of pore former in the 430L metal slurry changed the sinterability of the metal layer. This change of the sinterability of the metal support affected the final warpage state of the cell. This study aid in explaining the sintering phenomena between layers of metal-supported SOFCs.</p> 2021-11-18T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Effect of Dissolution Temperature on Purity of LaNi5 Powder Synthesized with the Combustion-Reduction Method 2021-08-13T10:52:56+07:00 Ade Utami Hapsari Retna Deca Pravitasari Hanif Yuliani Damisih Damisih Deni Shidqi Khaerudini Aghni Ulma Saudi Jarot Raharjo <p class="Abstract">The LaNi<sub>5</sub> intermetallic phase has been extensively investigated because of its excellent properties, such as attractive hydrogen storage, medium plateau pressure, and easy activation. LaNi<sub>5</sub> phase is generally produced by a complicated method, which involves several steps, i.e. melting, alloying, casting, softening and making them into powder. This study aimed to develop a new LaNi<sub>5</sub> synthesis process by modifying the combustion-reduction method. In this method it is very important to produce La<sub>2</sub>NiO<sub>4</sub>, because LaNi<sub>5</sub> is formed from the process of reducing this phase. The precursor powders La(NO<sub>3</sub>)<sub>3</sub>.6H<sub>2</sub>O and Ni(NO<sub>3</sub>)<sub>2</sub>.6H<sub>2</sub>O were reacted with distilled water as a solvent medium and mixed using magnetic stirring. The synthesis process was carried out at room temperature, 60 °C, 70 °C, and 80 °C for 10 minutes until the solution became transparent green. The solution was then dried for 2 hours at 100 °C to form a transparent green gel. The gel was calcined at a temperature of 500 °C for 2 hours, producing a black powder. The optimal black powder was then reduced using CO gas at 600 °C for 2 hours. The powder samples were characterized using XRD, FTIR, and SEM-EDX. The analysis revealed that synthesis at room temperature was the most optimal method for the reduction process because it produced the most La<sub>2</sub>NiO<sub>4</sub>, at 12.135 wt%.</p> 2021-11-18T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Tensile Characteristics of Bio-Composite Material Reinforced with Corn Skin 2021-08-13T11:39:27+07:00 Jefri Bale Yeremias Pell Kristomus Boimau Boy Bistolen Dion Rihi <p>The main focus of the present work was to study corn skin as reinforcement of polyester bio-composite (CSPCs). The effect of reinforcement type, i.e. short fibers and discontinuous chips, on the tensile properties was studied. The corn skin materials were chemically treated with NaOH and added as reinforcement of polyester bio-composite using the hand lay-up fabrication method. Tensile tests were carried out according to ASTM D3039. The tensile strength characteristics of stress and modulus showed a different behavior between the two types of reinforcement due to a slight difference in specimen thickness, which affected the calculated stress and modulus values. Furthermore, from a physical properties point of view, the larger surface area of CSC compared to CSF, which still contains a lignin layer after the treatment with NaOH, could decrease the interfacial bonding between polyester as the matrix and CSC as the reinforcement. The tensile damage characteristics showed brittle behavior, propagataing perpendicular to the loading direction. Matrix cracking and interfacial debonding were identified as the main two damage modes of the CSF bio-composite and the CSC bio-composite, where the final failure was dominated by fiber pull out and chip fracture.</p> 2021-11-22T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Correlation between Phase Behavior and Interfacial Tension for Mixtures of Amphoteric and Nonionic Surfactant with Waxy Oil 2021-03-09T13:16:35+07:00 Rani Kurnia Deana Wahyuningrum Doddy Abdassah Taufan Marhaendrajana <p>Phase behavior tests in the surfactant screening process for EOR applications remain one of the relatively convenient ways to design an optimum surfactant formulation. However, phase behavior studies are unable to provide quantitative data for interfacial tension, which is one of the parameters that must be considered when selecting surfactants for EOR. Several studies related to the prediction of interfacial tension through phase behavior testing have been carried out. In this paper, the Huh correlation was used to estimate the interfacial tension value based on phase behavior tests. It was found that the current form of the Huh correlation may be applied for the below-to-optimum salinity condition. Furthermore, the constants of the equation vary depending on the surfactant type and mixtures. </p> 2021-10-04T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Membrane Oxygenator for Extracorporeal Blood Oxygenation 2021-04-20T13:06:01+07:00 Enny Ratnaningsih Putu T.P. Aryanti Nurul F. Himma Anita K. Wardani K. Khoiruddin Grandprix T.M. Kadja Nicholaus Prasetya I Gede Wenten <p>Extracorporeal blood oxygenation has become an alternative to supply O<sub>2</sub> and remove CO<sub>2</sub> from the bloodstream, especially when mechanical ventilation provides insufficient oxygenation. The use of a membrane oxygenator offers the advantage of lower airway pressure than a mechanical ventilator to deliver oxygen to the patient’s blood. However, research and development are still needed to find appropriate membrane materials, module configuration, and to optimize hydrodynamic conditions for achieving high efficient gas transfer and excellent biocompatibility of the membrane oxygenator. This review aims to provide a comprehensive description of the basic principle of the membrane oxygenator and its development. It also discusses the role and challenges in the use of membrane oxygenators for extracorporeal oxygenation on respiratory and cardiac failure patients.</p> 2021-10-04T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Evaluation of Lateral and Axial Deformation for Earth Pressure Balance (EPB) Tunnel Construction Using 3 Dimension Finite Element Method 2021-03-16T11:16:30+07:00 Fahmi Aldiamar Masyhur Irsyam Bigman Hutapea Endra Susila Ramli Nazir <p>Mass Rapid Transit Jakarta (MRTJ) phase 1 tunnel construction using the earth pressure balance method has been completed and surface settlement and lateral displacement data according to elevation and inclinometer readings has been collected to evaluate the effect of tunnel’s construction on surrounding infrastructure. Soil stratification along the research area, defined according to boring logs and soil parameters for the hardening soil model (HSM) and the soft soil model (SSM), was determined by optimization of stress-strain curve fitting between CU triaxial test, consolidation test and soil test models in the Plaxis 3D software. Evaluation of the result of surface settlement measurements using an automatic digital level combined with geodetic GPS for elevation and position control points showed that the displacement behavior was affected by vehicle load and stiffness of the pavement. Lateral displacement measurements using inclinometers give a more accurate result since they are placed on the soil and external influences are smaller than surface settlement measurement. The result of 3D finite element modeling showed that surface settlement and lateral displacement during TBM construction can be predicted using HSM with 2% contraction. SSM and the closed-form solutions of Loganathan and Poulos are unable to provide a good result compared to the actual displacement from measurements.</p> 2021-10-22T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Characteristics of Rainfall-Induced Slope Instability in Cisokan Region, Indonesia 2021-02-23T15:15:01+07:00 Sugeng Krisnanto Harianto Rahardjo <p>A 25.5 km long access road has been constructed in a hilly area in Cisokan region. Several slope instabilities occurred during the rainy season, particularly at the end of heavy rainfall. A comprehensive study was performed to understand the characteristics of rainfall-induced slope instability. The study consisted of field observation, analyses of field and laboratory test data, and numerical analyses. The study revealed that in general there were two categories of slopes with instability characteristics: (i) slopes with a significant groundwater level increase during rainfall; (ii) slopes with an insignificant groundwater level increase during rainfall. In the first category, the slope instability was caused by a loss of matric suction and eventually the pore-water pressure, <em>u<sub>w</sub></em> became positive as indicated by an increase of the groundwater level. In the second category, the slope instability was caused by a loss of matric suction without a rise in pore-water pressure, <em>u<sub>w</sub></em>, to a positive magnitude. Two empirical curves of slope stability were developed as a preliminary guidance to assess slope stability during rainfall in the region.</p> 2021-10-22T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Improved Modified Symbiosis Organisms Search (IMSOS): A New and Adaptive Approach for Determining Model Parameters from Geoelectrical Data 2021-05-10T13:28:28+07:00 Sungkono Sungkono Hendra Grandis <p>Symbiotic Organisms Search (SOS) is a global optimization algorithm inspired by the natural synergy between the organisms in an ecosystem. The interactive behavior among organisms in nature simulated in SOS consists of mutualism, commensalism, and parasitism strategies to find the global optimum solution in the search space. The SOS algorithm does not require a tuning parameter, which is usually used to balance explorative and exploitative search by providing posterior sampling of the model parameters. This paper proposes an improvement of the Modified SOS (MSOS) algorithm, called IMSOS, to enhance exploitation along with exploration strategies via a modified parasitism vector. This improves the search efficiency in finding the global minimum of two multimodal testing functions. Furthermore, the algorithm is proposed for solving inversion problems in geophysics. The performance of IMSOS was tested on the inversion of synthetic and field data sets from self-potential (SP) and vertical electrical sounding (VES) measurements. The IMSOS results were comparable to those of other global optimization algorithms, including the Particle Swarm Optimization, the Differential Evolution and the Black Holes Algorithms. IMSOS accurately determined the model parameters and their uncertainties. It can be adapted and can potentially be used to solve the inversion of other geophysical data as well.</p> 2021-11-01T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences New Method of Materials Flow Calculation for Double-String SLCI Type Cement Plant (Part 1: The Whole Clinker Plant) 2021-02-26T09:53:53+07:00 Prihadi Setyo Darmanto Izzan Hakim Muzakki I Made Astina Firman Bagja Juangsa Alfi Amalia Arief Syahlan <p>Materials flow values are instrumental in many industries for controlling and simulating processes, designing new equipment as well as modifying existing plants. They are sometimes impossible to determine by direct measurement in an operating plant due to the very high temperatures. This study attempted to overcome the difficulties associated with this measurement by proposing a new method to calculate materials flow of a double-string suspension preheater type of cement plant with separate line and in-line calciners (SLC-I), with heat balance error less than 1%. This study was divided into two sequential parts, with the first part presented in this paper. The methodology of the first part was to solve the conservation law of the main clinker plant equipment, supported by Bogue’s equation, the heat of calcination, and the thermodynamic properties of the related materials. The least-square method was employed for solving the overdetermined system equations obtained in the second part. The results of the first part were: the ratio of heat formation to specific heat consumption was 52.13% (&gt; 50%), and the gas exhausted from the plant yielded more than 117 MW heat equivalent, which can potentially be recovered for electricity production.</p> 2021-11-02T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Thermal Performance Analysis of a Newly Designed Circular Firewood Boiling Salt Stove 2021-03-31T14:19:23+07:00 Apichart Srichat Weerapol Kaewka Ponthep Vengsungnle Songkran Wiriyasart Paisarn Naphon <p class="Abstract">Different biomass stoves are introduced and distributed among people living in rural and urban areas, especially in developing countries. For salt crystal production in Thailand’s rural north-eastern area, open fire stoves are used in domestic and small productive activities. Their thermal efficiency is very low for converting heat into utilization energy. A new stove with a circular configuration was designed and constructed to consider its thermal efficiency and economics, which were compared with those from a traditional and an improved traditional stove. The obtained thermal efficiency of the newly designed stove was 14.77% higher than that of the improved stove and 81.45% higher than that of the traditional stove. For the same initial saline volume, the final amounts of salt crystals and salt flowers obtained from the newly designed stove was higher compared with those obtained from the improved stove and the traditional stove, respectively, resulting in a 69.25% shorter payback period.</p> 2021-11-02T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Performance Investigation of MIMO Based CO-OFDM FSO Communication Link for BPSK, QPSK and 16-QAM under the Influence of Reed Solomon Codes 2021-03-31T09:27:55+07:00 Suresh Kumar Payal Payal <p>The MIMO based CO-OFDM FSO communication system is emerging as a promising approach to meet the future bandwidth requirements for seamless communication. The atmosphere being the propagation medium is a major hindrance in wide-scale acceptability of FSO technology. For seamless and error-free transmission and reception of data, a novel concept of MIMO integrated with RS code is proposed in this paper. The system performance of an RS 64 (RS (255,127)) coded MIMO-based CO-OFDM FSO communication link was investigated using BPSK, QPSK and 16-QAM under the combined effects of geometric losses, path losses and atmospheric attenuations at a hitherto un-investigated data rate of 40 Gbps and a link distance of 5 km. The modified gamma-gamma distribution was used for modeling a moderately turbulent channel. With link length varying over a range of 1 to 5 km, error correction was maximum in 16-QAM as compared to BPSK and QPSK, with 150 to 167 corrected errors. In terms of PAPR, PSK was more apt than QAM, but with a compromise in BER. The geometric losses were reduced with link length due to an increase in error correction capability for all three modulation cases, with the least losses occurring in 16-QAM. At the target bit error rate (BER), the signal to noise ratio (SNR) required for BPSK and QPSK was higher by 3.98 dB and 6.14 dB compared to 16-QAM.</p> 2021-11-11T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Reliability Analysis of Metro Door System Based on Fuzzy Multi-State Bayesian Network 2021-07-26T16:58:39+07:00 Zhenliang Fu Na Li Xueyan Tian Yonghua Li Ziqiang Sheng <p>Considering the shortcomings of the fault tree analysis (FTA) method in the reliability analysis of metro door systems, Bayesian network (BN) and fuzzy theory were introduced to establish the failure probability model of a metro door system. A fault tree of the metro door system was established based on the structure of the metro door, the operation data record and the practical experience of relevant engineers. The BN of the metro door system was constructed based on the fault tree. For the problem that the prior probabilities of root nodes with missing data were unavailable, fuzzy theory was introduced to convert the expert language values on these missing data nodes to corresponding prior probabilities, which were substituted into the BN along with the root nodes whose prior probabilities were obtained from the operation fault data to calculate the leaf node probability. Cause analysis of the metro door system was performed with bi-directional reasoning of BN, which provided a way to find the key factors that caused door faults and the metro door system fault probabilities.</p> 2021-11-11T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences Blending Lime with Sugarcane Bagasse Ash for Stabilizing Expansive Clay Soils in Subgrade 2021-05-07T21:59:04+07:00 Zalwango Teddy Bazairwe Annette Safiki Ainomugisha <p>Expansive soils constitute one of the most frequently encountered and challenging soils to geotechnical engineers. This study assessed the possibility of utilizing sugarcane bagasse ash (SCBA) by partially replacing slaked lime to stabilize expansive clay soils. The soil samples were picked from Muduuma area, Mpigi district, Central Uganda. Experimental tests of linear shrinkage (LS), plasticity index (PI), and California Bearing Ratio (CBR) were conducted on both unstabilized soil and SCBA-lime treated samples. The SCBA-lime mixture was prepared by partially replacing 5% lime with SCBA at 2, 4, 6, 8, and 10% by weight. Hence, SCBA was used in proportions of 0.1, 0.2, 0.3, 0.4, and 0.5% by dry weight of the soil. The addition of lime greatly lowered the PI and LS, which later increased with the addition of the SCBA. The maximum dry density was generally lowered with the addition of lime and SCBA, from 1.87 g/cm<sup>3</sup> to 1.58%. The CBR increased with SCBA-lime addition from 12% for unstabilized soil up to 48% at 6% SCBA replacement. The optimum lime replacement was established as 6% SCBA lime replacement based on CBR criteria. At the 6% optimum, the optimum moisture content (OMC) was 1.7 Mg/m<sup>3</sup>, LS was 10%, and PI was 20%. This study demonstrated the potentiality of SCBA as a novel construction material, specifically by partially reducing the usage of the unsustainable, non-environmentally friendly lime. It is also expected to enable using currently unsuitable clays from the region.</p> 2021-11-11T00:00:00+07:00 Copyright (c) 2021 Journal of Engineering and Technological Sciences