bluuebunny/crossref_metadata_2025 huggingface dataset:
Zooplankton study in Bukit Merah Reservoir, Malaysia: a preliminary biodiversity assessment
Authors: Ismail A H , Aziz N S , Zainal Z F , Abdullahi Z H , Haziqah M T F , Wan Maznah W O
Published: March 2021

Anthropogenic activities including uncontrolled development and agricultural intensification in the catchments area accelerate the sedimentation rate in lake and reservoir. Bukit Merah Reservoir is one of the freshwater ecosystems facing sedimentation issue and a major threat to its water quality from anthropogenic activities. These activities lead to invariably changing in water quality parameters and become the primary cause of variations to aquatic biodiversity such as zooplankton. This study investigated the biodiversity of zooplankton as a preliminary assessment in Bukit Merah Reservoir, the oldest artificial reservoir in Malaysia. Water and zooplankton samples were collected from six sampling stations which cover the littoral, limnetic and pelagic zones of the reservoir. Zooplankton analysis showed the presence of 49 taxa belonging to the three main groups of freshwater zooplankton dominated by Keratella cochlearis, Trichocerca sp., Polyarthra sp., Bosminopsis deitersi and Diaphanosoma sp. Analysis of variance revealed a significant difference was found (P<0.05) between the sampling stations during the study period. Zooplankton biodiversity reflects the water quality condition at the time of sampling that indicates the health of aquatic water body in the study site.
Role of plant genetic resources in encountering climate change challenge
Authors: Ichsan C N , Darusman  , Sulaiman M I , Andini R
Published: March 2021

The world is encountering a global threat: climate change. It is estimated that the average air temperature will raise 3.7 - 7.8 °C by 2100. The possible impacts will vary, however, agriculture will be adversely affected marked with yield loss of staple crops such as rice and maize and altered post-harvest quality of horticulture products. On the other hand, the world Food and Agriculture Organization (UN-FAO) has set a target ‘zero hunger’ by 2030’, despite the five big challenges ahead: i) protracted conflict, ii) growing inequality, iii) rapid urbanization, iv) economic challenges, v) drought and natural disasters. The existing plant genetic resources, particularly the wild, neglected, and underutilized species has a great role and bears big potential to be exploited and targetted to achieve food and nutrition security, esp. in the densely populated regions with malnutrition problem e.g. in Asia and sub-Saharan regions. However, a key to future and sustainable crop production lies in the collection of crop and their wild relatives stored in ex-situ, or in-situ. This paper aims to explain the importance of plant genetic resources as well as the potential of some underutilized crops closely attributed with drought resistence, such as sorghum (Sorghum bicolor L. Moench), amaranth (Amaranthus sp.). These crops bear potential to support national food security program.
Determination of insecticides diagnostic doses in susceptible Culex quinquefasciatus (Diptera: Culicidae)
Authors: Bukar A , Hamzah S N
Published: March 2021

Despite Mass Drug Administration cases of Lymphatic filariasis still exist in several developing countries such as, China, India, Indonesia, Malaysia and several Southeast Asian countries. Culex quinquefasciatus is the major vector that is dominant and widespread mosquito distributed in rural and urban areas. This study aimed at determining the diagnostic doses of LC50 and LC90 (lethal concentrations that causes 50% and 90% mortality respectively) of commonly used insecticides in Malaysia for dengue vector control by Malaysian Ministry of Health. The diagnostic LC50 of the Malathion, Pirimiphos methyl, Temephos and Deltamethrin insecticides were determined at 0.019mg/L, 0.0060 mg/L, 0.0011 mg/L and 0.0032 mg/L as well as LC90 0.033 mg/L, 0.012 mg/L, 0.0033 mg/L and 0.0010 mg/ml respectively. It is concluded that various LC50 and LC90 diagnostic doses of these insecticides were effective against the susceptible population of Cx. quinquefasciatus that also carries infective third instar larvae (L3) microfilariae. We recommend the use of these doses for effective control of Cx. quinquefasciatus population and constant monitoring of its susceptibility status will provide more information on the possible resistance that may affect the effort in the elimination of Lymphatic filariasis in affected countries.
A current perspective on antibacterial and antibiofilm properties of waru (Hibiscus tiliaceus L.)
Authors: Husnah M , Suhartono S , Ismail Y S
Published: March 2021

During the long course of evolution, disease-causing pathogenic bacteria have developed a variety of virulence mechanisms that help them establish and maintain infections. Among these mechanisms are the production of biofilm protecting the bacteria from undesirable environmental conditions and contributing to the development of new multi-drug-resistance bacterial strains. Hence, biofilm has become an attracted target for the development of a novel strategy in fighting against biofilm-forming pathogens. There has been much work to look for novel antibacterial and antibiofilm agents, including the use of plant-derived materials.Hibiscus tiliaceusis one of the widely known medicinal plant with antibacterial and antibiofilm properties. This review focuses on antibacterial and antibiofilm properties ofH. tiliaceusas well as the major phytochemical constituents that might contribute to these activities.
Decreased of calcium oxalate levels in the purple taro flour (Colocasia esculenta) from Aceh Province, Indonesia using three immersion methods
Authors: Rozali Z F , Zulmalisa Z , Sulaiman I , Lubis Y M , Noviasari S , Eriani K , Asrizal C W
Published: March 2021

Cocoyam (Araceae family) tuber, like purple taro, traditionally are used as sources of non-rice carbohydrates in Aceh Province, Indonesia. But it contain high calcium oxalate, which contributes to kidney stones formation. Immersion in strong acid (HCl) solution can reduce calcium oxalate. However, it will cause a very strong taste and aroma in cocoyam flour. So, it is necessary to use other immersion methods. This research aimed to examine the effect of the immersion method to reduce calcium oxalate in purple taro flour. The immersion methods used in this research are weak acids (CH3COOH), salt (NaCl), and alkaline salt (NaHCO3). Calcium oxalate, moisture, and ash content were the parameters observed in this study. The result showed that all immersion methods can reduce calcium oxalate levels in purple taro flour. The lowest oxalate content (42.64 mg/100 g) was obtained by the NaHCO3 immersion method. The NaHCO3 had a significant effect to decrease calcium oxalate content in purple flour
Potential of betacyanin as inhibitor of SARS-CoV-2 revealed by molecular docking study
Authors: Tallei T E , Tumilaar S G , Lombogia L T , Adam A A , Sakib S A , Emran T B , Idroes R
Published: March 2021

Covid-19 is a global pandemic where an effective drug has yet to be found. A new coronavirus species, SARS-CoV-2 causes this disease. Several studies have been conducted on medicinal plant-based lead compounds to find antidotes for this virus. One of the fruits that with a high betacyanin content is super red dragon fruit produced by plant Hylocereus costaricensis. Betacyanin, besides having anti-inflammatory and immunomodulatory activities, also has antiviral activity. Therefore, this study aimed to evaluate betacyanin’s interaction with several SARS-CoV-2 receptors by observing its binding affinity and compared it with the nelfinavir and hydroxychloroquine sulfate that have been recommended for treating COVID-19. This research was an in silico study using computer software to assess binding affinity simulations based on molecular docking. The results of this study indicated that betacyanin had a good affinity with several receptors so that it has the potential to be developed as a lead compound to overcome COVID-19. Based on its binding affinity value, betacyanin’s ability was comparable to nelfinavir and hydroxychloroquine sulfate recommended by WHO as a therapeutic agent for COVID-19.
Assessment of water quality index of Puah Reservoir, Hulu Terengganu, Malaysia
Authors: Abubakar M K , Ruddin M S A S , Filza E A , Ahmad Nazri S , Shahril M S
Published: March 2021

Puah dam is located 50 km from Bandar Gua Musang – Hulu Terengganu roadway, and about 65km west of Kuala Terengganu. Puah Reservoir is used for macro-hydro power plant (capacity 250MW). The purpose of this study was to determine the water quality status of the reservoir. Based on water quality index grading, the reservoir water has been classified as poor according to WHO WQI rating with a calculated range of 11.52 – 485.71. Although, the result for the mean WQI for all the stations/locations (48.04 – 154.36) revealed that the water is fit for drinking purpose through any form of treatment. However, it’s relatively good for swimming, bathing, laundry, irrigation and industrial purposes. This condition showed that the activities of Tambat and Puah hydro-power generation had no negative effect on the water quality of upper and lower parts of Puah Reservoir respectively.
Deformation and dynamic stability of asphalt concrete by using granite dust as filler
Authors: Oesman M , Sundara A , Endawati J , Virnawan D
Published: March 2021

Asphalt Concrete – Wearing Course (AC-WC) is a surface layer of flexible pavement which have direct contact with vehicle wheel. One of the surface layer damage categories is the wheel track (rutting). In this research, the experiment was done by using industrial waste of granite stone production in the form of dust as filler in the AC-WC mixture. The variation of filler content used are 3%, 4.5%, 6%, 7.5% and 9% with cement filler as comparator. The test was conducted by using wheel tracking machine on temperature of 60˚C, 45˚C and 30˚C. The test result shows that the optimum filler content using granite dust in the AC-WC mixture is 3%. Meanwhile the optimum filler content on the asphalt concrete using cement filler is 7.5%. Thus, it shows that the higher temperature cause the ability of maintaining the wheel track decreased. Furthermore, if looking at the relation between dynamical stability, deformation depth and deformation velocity on filler concentration is not linear.
Innovative products of concrete steel bone testing tools in the field of civil engineering building
Authors: Hadi T , Pamungkas N S , Wahjoedi W , Mulyono T
Published: March 2021

Bending test is one type of material testing conducted to determine the mechanical properties of a technical material. In designing this bending test required a standard design method that uses standard machine elements as well as commonly found in the market. In practice in the field, there are only a few materials testing practitioners who pay attention to aspects and effects of variations in the dimensions of the test specimen on the data from the test results. The test is carried out with the intention to obtain information about fulfilling the quality requirements and the feasibility of the material to be used as construction material for buildings, bridges and other physical buildings. As for one application that can be done is to look at aspects of the problems that are around that are associated with practicum activities in the laboratory and in the work industry. Therefore it is necessary to adjust between making the final report with the needs needed in the industrial world. For this reason, the bending test is made to study the effect of dimensional variations on test specimens in arcing testing. For this reason, this study with the title “Innovative Products for Concrete Reinforcement Steel Curved Test Equipment in the Field of Building Materials in the Department of Civil Engineering” is very important to do. The research was conducted to improve the performance of tools in the building materials laboratory. The final results of the study are expected to function optimally and easily used for laboratory work.
Monitoring rainfall intensity and moisture water content using soil column experiment
Authors: Mukhlisin M , Yunanto B , Suharjono A , Martono M , Apriantoro R , Kusumawardani R
Published: March 2021

Indonesia is a tropical country that has two seasons, rainy season and dry season. The wetting and drying of soil due to changing of the seasons caused change on soil properties such as moisture soil water content, effective soil porosity, soil suction etc. During rainy season, rainfall infiltration caused increasing of moisture soil water content in a soil slope, tends to reduce soil shear strength and followed by slope instability. In this soil column experiment was set up with rain gauge station and YL-69 sensor and capacitive soil moisture sensor to monitor rainfall infiltration and soil moisture water content in red clay soil. A wireless sensor network with low power wide area network technology integrated with the cloud to observe rainfall intensity and soil water content in soil column with realtime monitoring. The focused on improving the accuracy of rainfall intensity and soil water content sensors readings using regression methods. The experiment results showed that rainfall intensity was observed accurately while for the YL-69 sensor, the error reading was 5.15% and the error reading capacitive soil moisture sensor was 2.99%.
Emission comparison of short lived climate forcers over long term greenhouse gases from domestic and transport sector in Semarang city
Authors: Huboyo H , Samadiku B , Manullang O
Published: March 2021

Short-lived climate forcers (SLCF) controls are important because of their shorter impact and more immediate benefits in the short term than carbon dioxide controls that have a 100-year time horizon. In this study, we estimated the emission of SLCF from domestic and transport sector in Semarang city using emission factor from IPCC and CORINAIR. We also predicted the emission dispersion using AEMOD View. The total consumption of LPG domestic sector in Semarang city is 48,532 tons in 2017 and produces total SCLF emissions 0.537 tons/year and 11,538 tons/year for BC and CH4 respectively. This corresponds to CO2 emissions of 145,611 tons/year and 230.76 tons/year of N2O emissions. While from transport sector, the motorcycle has the largest VKT i.e 18.282.061.600 km/year in 2017. The emission, based on VKT data combined with active vehicles data, reach 178.23 tons/year, 802.52 tons/year for BC and CH4 respectively. Transport sector produces total CO2 emissions almost 15 times to that of domestic sector. Based on emission model, the emission distribution was concentrated in the districts located in the city center. The pollutant was accumulated in the Northwest, city center and Southeast of the city.
Electronic system of rubber belt electro-mechanical continuously variable transmission for motorcycle applications
Authors: Supriyo B , Ariyono S , Sihono S
Published: March 2021

This paper deals with the design of electronic system for changing the transmission ratio of a rubber belt electro-mechanical continuously variable transmission (CVT) for motorcycle applications. In this CVT, the rubber belt is used as a medium to transfer both the speed and torque from the input pulley to the output pulley based on contact friction force existed between the belt and both pulley surfaces. Each pulley set consists of one fixed and one sliding pulley sheaves. The axial position of the input sliding pulley sheave is detected using a two channel incremental rotary encoder and controlled by an electro-mechanical shifter system utilizing DC motor, actuator gear set and cam mechanism. The sliding sheave of the output pulley is axially pushed by contra spring to provide sufficient belt compression for preventing belt slip. The CVT ratio is changed by varying the input and output belt-pulley contact radii. It can be done by controlling the axial position of sliding input pulley sheave, the angular speeds of input and output pulleys are sensed using one channel incremental rotary encoders. By knowing these two speed values, the CVT ratio can be computed. The microcontroller system of Arduino is programmed to detect and control the axial position of the input sliding pulley sheave to regulate the CVT ratio. The experimental results show that the electronic system can perform the CVT ratio changes adequately.
Prediction effective capacity battery of cellular BTS for an effective maintenance
Authors: Harijadi M B , Andromeda T , Somantri M
Published: March 2021

A cellular base transceiver station (BTS) systems must be operated continuously in transmitting signals to the mobile stations. Reliability operation must be performed by this BTS to serve users without any interruptions. In several cases the BTS are found failed due to several disturbances that occurred during operation. One of the disturbances is caused by electrical energy supply interruptions. Although the cellular BTS power supply system is usually equipped by battery as a secondary power supply, the reliability can be influenced by the health of the battery. The health of battery is inclined by instability of main electricity supply, temperature fluctuation of the battery environment, increment of battery aging, the number of charging and discharging cycles (CDC), and the number depth of discharging conditions (DOD) that occurred. The impact of these factors will affect to the strength of battery. This paper proposes an investigation method to the battery health to ensure the performance of BTS. The method is applied by considering the charging and discharging characteristics of the battery. Since the characteristic signals are not linear, the calculation is performed using fuzzy method. Early results show that this prediction method can be applied to support maintenance work. The proposed method gives an overview of the battery health that can be followed up by technician to ensure the reliability of the BTS.
Web-based rule-based system for early detection of anemia among pregnant mothers
Authors: Veronica S Y , Widyawati M N , Suryono S
Published: March 2021

Anemia among pregnant mothers is a serious issue that may cause pregnancy complications, premature birth that can lead to mortality, and low birth weight (BBLR). Monitoring for anemia among pregnant mothers is quite a phenomenon for midwives and health professionals due to time constraint as it takes time to establish a proper diagnosis. Late diagnosis establishment results in late treatment. Therefore, this paper proposes a web-based rule-based information system using the rule-based algorithm to ease monitoring and detection of anemia among high risk pregnant mothers. The method employed is online rule-based information system to diagnose anemia among pregnant mothers. Respondents input data of symptoms that will then be processed by the information system to generate diagnoses. Resulting diagnoses are displayed as they are. The rule-based method in the information system validates data of symptoms and diagnoses with experts in the field to serve as reference in providing health care information. This is a pre-experimental research with one posttest group. The intervention group (N=10) was given treatment using the information system, while the control group (N=10) was given treatment manually. Interventions were conducted for 20 days, and measurements were carried out on the 21st day using the Technology Acceptance Model (TAM). The anemia detection system for pregnant mothers developed here is proven to be effective in helping anemia detection and has been validated by experts (midwives) and hence, been declared valid. With effectiveness score of 90 %, this web-based rule-based information system is effective in detecting, monitoring, and reporting anemia among pregnant mothers.
Study method accordance for presstool design learning between POLINES and PT Mekar Armada Jaya in the framework of link & match
Authors: Wattimena R M , Ardjo A S , Hartono H , Alfauzi A S
Published: March 2021

PT Mekar Armada Jaya, located in Cibitung, Bekasi, West Java, is a national-scale industry engaged in manufacturing various vehicle parts, especially those made of steel sheets. The process of making various parts of this vehicle requires a press tool. This company designs, makes, studies, and develops all the required press tools, therefore human resources (HR) are needed who have the competency to design and make presstools. Based on this, PT Mekar Armada Jaya held a partnership to produce the intended HR needs, namely graduates of the D3 Mechanical Engineering study program who were ready to work both at this company and at other similar companies. Along with the link between the Semarang State Polytechnic and PT Mekar Armada Jaya above, it is necessary to study the alignment of methods and learning strategies for the presstool design. The results of this study are in the form of design learning methods that will be carried out in the D3 Mechanical Engineering study program and learning handouts for the topic of presstool design.
Analysis of vibration due to misalignment in the clutch cluster installation of centrifugal pump
Authors: Widodo I G , Khoryanton A , Pramono A
Published: March 2021

Knowledge of vibration and the resulting data is very important for maintenance and troubleshooting where this ability can help companies reduce the occurrence of downtime and can increase profits both in terms of production and from a longer machine life. One of the causes of high vibrations is a misalignment in a centrifugal pump installation that is driven by an electric motor and connected by a fixed clutch. The method used is to do differences in height in the horizontal, vertical and angular directions by providing variations in the rotation of the electric motor and pump, then checking at four bearing positions on the electric motor and pump. The results showed an increase in vibration at each addition of the sim on the electric motor fastener bolts, the greatest vibration occurred in the MOV (indoor motor axiall) with the addition of a 1.5mm sim of 3.01 mm / sec an average increase of 29% and at the largest pump vibration in POA (outdoor axial pump) with the addition of a 1.5mm sim of 9.88mm / sec, increased by an average of 58%.
Model for identification of rice type using combination of shape and color features
Authors: Jumi J , Zaenuddin A , Mulyono T
Published: March 2021

Rice is an agricultural commodity that is a staple food in Indonesia with hundreds of types of rice that have different characteristics. The type of rice can be distinguished from color and shape. The main feature that is dominant and can distinguish each type of rice is the color and shape. This feature is the main key in identifying types of rice. Identification is done by comparing the similarity of rice images using the value of color and shape features. The similarity can be determined through the difference in feature values between the query image and the database image. The closer the difference is to zero, the higher the level of similarity. The degree of similarity will affect the accuracy of image recognition at the time of identification. In this study, an analysis of the accuracy of image identification and measurement of computation time was carried out. Improved identification accuracy using the weighting of color and shape feature values. Extraction of the two value features using the invariant moment and color moment. Preprocessing before extraction using Grayscale, resize, edge Enhancement, Histogram Equalization. Clustering of rice image data using K-Means clustering. The results showed that the accuracy of identification with 400 rice image test data, reached more than 95% in the weighting scheme Ws (weighted Shape) = 40% and Wc (weighted color) = 60% with an average computing time of 5 milliseconds at 10 the cluster.
Design models of automatic humidity control system in flash off painting line room to reduce defect products at PT. Kubota Indonesia
Authors: Khoryanton A , Giyanto G , Satito A , Harmanto S , Haryanto H , Tegar T
Published: March 2021

The main challenge often faced by PT. Kubota Indonesia in connection with the quality of production is still a lot of level of disability in the production process, especially in the painting process. The process of painting is highly required according to the standard of both the process and condition of the room so that the results of the painting do not occur defects. Based on production data in the period from October 2018 to January 2019 there were 80% defective products with blistering defects of the total defective products, this needs a deeper analysis of the causes of product defects. Blistering defects in the form of bubbles on the surface of the painting result occur because the standard of air humidity is not achieved when the flash off process is caused because there is no tool to condition the air in the flash off the chamber. The purpose of this research is to design an automatic humidity control system model that can be used as an alternative to PT. Kubota Indonesia as a method for reducing humidity so that it can reduce the potential causes of blistering defects. Research methods include problem identification, literature study, design, and manufacture of models and testing. Problem identification is done by using the 5M + 1E method to find the root of the problem. The process of designing and making models is divided into 3 important activities namely designing 3D design concepts using solid works software, designing a control system software with Arduino Uno and designing hardware models. Tool testing is done by testing the automatic humidity control system model on the prepared test chamber model. The results obtained from this study are models of automatic humidity control systems that can condition the humidity in the test room and maintain the humidity according to the setpoint.
Effect of Vibrating Fluidized Bed (VFBD) and continuous microwave drying on drying characteristic of green tea
Authors: Handayani S U , Yulianto M E , Sutrisno S , Ariwibowo D , Amalia R , Hartati I
Published: March 2021

In industrial green tea processing, people usually use endless chain pressure (ECP) dryers and fluidized bed dryers. ECP dryers have disadvantages including case hardening, uneven dryness, high energy consumption and long drying time, while fluidized bed dryers still have disadvantages of long drying time and high hot air capacity to ensure tea leaves can be fluidized perfectly. Therefore, another alternative dryer is needed that can overcome the problems in the ECP dryer and fluidized bed dryer. This study aims to determine the comparison of drying characteristics between vibrating fluidized bed dryer (VFBD) that have been developed previously with microwave dryers. Drying condition on both dryer was set at 80oC, the airflow velocity at VFBD was 1.09 m/s. Result shows the time needed by the microwave at temperature to dry 500 grams of tea leaves to reach a constant weight is 24 minutes, whereas if using VFBD it takes 85 minute. In VFBD, the constant rate period takes 25% of total drying time, and the rest is critical and falling rate period. While in microwave drying, around 50% of total drying time is constant rate period and the rest is critical and falling rate period. The falling rate period in VFBD requires longer time, which is up to 75% of the total drying time. Highest drying rate in VFBD dryer was 0.08 gr water/gr solid.min, while microwave dryer was 0.14 gr water/gr solid.min.
Maintenance information system development for Powerhouse Department on diesel engine manufacturer
Authors: Ardjo A S , Wardihani E D , Slamet A , Habiburrahman M H
Published: March 2021

The Powerhouse Department on a diesel engine manufacturer has the role of supplying electricity to all departments, especially the production department. The problem that arises is the recording of all maintenance and repair activities carried out in the logbook. The purpose of this research is to develop a maintenance information system that can record all maintenance and repair activities that can be recorded electronically. The method used is Object-Oriented Development (OOD). The results of the research are data of toolst, parts & spare-parts, maintenance history & engine damage, maintenance scheduling documents, and vendor & supplier data. The system was implemented on this manufacturer.
Design and fabrication of a transmission mechanism arm for rotational molding
Authors: Thi H N , Dang N V , Thu Ha Thai Thi
Published: March 2021

Compared with blow molding and thermoforming technology, rotary die technology has many advantages for manufacturing hollow plastic products. The purpose of this paper is to compute and design the transmission crank mechanism of the rotary die machine. The authors chose a reasonable solution to design the experimental model to produce flower pots with dimensions of 1000 x 400 x 400 mm. The principle diagram and the dynamic diagram of the machine are presented. Computation and design of main clusters and hand fabrication of the rotary die machine are investigated. The model of the transmission crank mechanism is fabricated to verify the validity of the proposed model.
Design investigations on a 2-speed gear reducer for agricultural application
Authors: Luces J L , Manuel M C E
Published: March 2021

A dual-speed gear reducer was designed to offer a broader application to the common single-speed reducers. However, in order to provide additional value to the design, an investigation was made to determine the effects of varying the normal module, center distance, and facewidth on the gear components of the dual-speed gear reducer. KISSsoft gear simulation software was used to perform the computation for each variation in the mentioned parameters. The optimized values were based on the calculated parameters of gears with the root and flank safeties of not less than one or greater than 3000 hours service life as minimum standard for designing gears used for agricultural application. Based on the investigations made the increase in normal module, center distance, and facewidth also increases the flank and root safeties of both drive and driven gears. However, increasing further the normal module decreases the flank safeties of both gears. Nevertheless, increase in normal module with corresponding increase in center distance considerably increases both the root and flank safeties of gears. Finally, a dual-speed gear reducer was fabricated that proved the data generated using KISSsoft was useful for efficient manufacturing and assembly of the gears and gearbox, respectively.
Design, fabrication, and testing of an automated machine for the processing of dried water hyacinth stalks for handicrafts.
Authors: Amante K , Ho L , Lay A , Tungol J , Maglaya A , Fernando A
Published: March 2021

In this paper a portable machine that is capable of pressing and cutting dried water hyacinth stalks was designed, fabricated and tested. This prototype will help automate the laborious manual cutting of the water hyacinth dried stalks. The machine will flatten the dried stalks and cut stalks into three different widths of 0.5in, 0.25in, and 0.75in. This machine might improve the consistency and quality of the pre-cut stalks. This will also help workers focus on other handicraft processes such as weaving thus improving productivity and helping the local handicraft industry by providing a low-cost alternative equipment.
Performance evaluation and characterization of a locally designed water pump
Authors: Pascual A S , Fajardo A L , Zubia O F , R A Luyun Jr R A
Published: March 2021

Voltron, a locally designed water pump, is widely used among farmers in Central Luzon of the Philippines. The study aimed to evaluate the performance of the Voltron water pump. Voltron was tested at different pump shaft speed settings of 450, 600, and 700 rpm and with different blade (impeller vanes) numbers of 6, 8, 9, and 10 using V-belts and B-section pulleys transmission. The highest pump efficiency of 62.5% was observed using an 8-vane impeller under a 700-rpm setting. Currently, farmers utilized the 8-vane impeller under a 600-rpm setting. Statistical analysis showed that there is no significant difference between the pump efficiencies on the set pump shaft speeds, but there is a significant difference in the set number of vanes. On the other hand, the effects of pump shaft speed, the head, discharge, and fuel consumption increased as rotational speed was increased. The difference is around Php 17.61 per ha per day of operation favoring the usual setting upon the computation of the fuel cost. However, the 8-vane impeller under a 700-rpm setting will be more economical in the long run as it is determined to be more efficient than the normal setting being used by the farmers.
Reliability based design of shaft for gearbox
Authors: Loc N H
Published: March 2021

In this article, the author presents research on the reliability-based design methods of mechanical systems, includes 3 stages: the first, the fault tree analysis (FTA) method is utilized for reliability analysis of single and double reducer into the logic diagram; the second that apply the probabilistic design methods, including moment matching method (MMM), first-order reliability method (FORM), and Monte Carlo simulation (MCS) for reliability-based design and to analyze the components of the mechanical transmission systems, and the last sensitivity analysis is performed in the post-design stage after a design solution is identified. The study also aims to set up RADME (Reliability-based analysis and design of the mechanical systems) computer programs applying the aforementioned methods. The reliability design problem was surveyed as reliability-based design optimization with one design variable.
An innovative control system of a hybrid tankless water heaters using LabVIEW
Authors: Garcia R F , Chua A
Published: March 2021

This paper presents an innovative control system of a hybrid tankless water heater that provides a rapid response to deliver hot water within a desired temperature range at lower energy consumption. The proposed tankless water heater provides a hybrid heating process that composes of a gas fired heater as primary heater and an electric heating system as secondary heater. LabVIEW designing software was used in designing the control system. A controller was designed using a PID controller which response with respect to given input parameter such as changes in water flow and the inlet temperature. Through alteration of heat source, this efficiently reduces the power consumption of the tankless water heater during low water demand, and eliminate overshoots. Simulation results demonstrated that the proposed system has performed efficiently in a range of water flow and temperature demand while reducing power consumption for about 30%.
Analysis of the effects of geometry on the press fit application in automotive power modules
Authors: Ubando A T , Gonzaga J , Arriola E , Moran R L , Lim N R E , Mercado J P , Conversion A , Belarmino D
Published: March 2021

Semiconductors and electronics have been found to have an increasing use in automobile design. One key component of an automobile is the power module, which is a high voltage component that finds itself in extreme operating conditions. Due to this condition, the power module demands for highly effective terminal connections that can withstand the extreme operating condition specifically on the terminals that will connect the power module to the automobile system. Press fit technology has been a solution for cheap and reliable methods of creating interconnections since the 1980s; however, necessary innovations exist for more environmental design, and increase demand in quality and quantity. Press fits are simple, force-fitting connectors that allow permanent bonds without solder or adhesive bonding and a shortened process time. This research presents a unique methodology on the evaluation of the effects of the geometry to the insertion force and retention force using finite element analysis. The result showed that the geometry of the pin in a press fit pin configuration has a significant effect on the insertion force, retention force, as well as in the equivalent stress.
Design, Manufacture, and Testing of a Low-Cost Force Platform with 3-Axis Load Cell
Authors: Ferryanto F , Akbar M M , Wicaksono S , Mahyuddin A I
Published: March 2021

Force platform is an instrument to measure Ground Reaction Force (GRF) and locate Center of Pressure (CoP) in motion analysis. Although it is very useful, the cost of the commercially available force platform is relatively high. Therefore, the objective of this work is to develop a low-cost force platform with 3-axis load cell. The development was initiated with Design Requirement and Objective (DR&O) of the force platform. To measure the force, four 3-axis loadcells were placed in each corner of the force platform to measure a maximum force of 1500 N. The dimension of the aluminum 5058 force platform was 500 x 500 mm. After the manufacturing process, the force platform was calibrated to obtain 12 correction factors for the four loadcells in the three-axes. It was obtained that the RMSE of the correction factors was 0.87% inzdirection and lower than 2% forxandydirection of GRF. The CoP was also tested to ensure the functionality of the developed force platform. The RMSE errors for the CoP were 5 mm and 5.9 mm inxandycoordinates, respectively. With relatively small RMSE, the force platform could be used to obtain GRF and locate the CoP in gait analysis.
Development of a local unmanned aerial vehicle (UAV) pesticide sprayer for rice production system in the Philippines
Authors: De Padua E P , Amongo R C , Quilloy E P , Suministrado D C , Elauria J C
Published: March 2021

Currently, commercially available UAV Pesticide Sprayers in the Philippines are very expensive. Therefore, this study aimed to develop a locally made automated UAV Pesticide Sprayer for rice production system that is much cheaper than the current price in the market. Moreover, the One-liter Capacity UAV Pesticide Sprayer has an autopilot flight control system- allowing the pilot to fly the UAV without directly maneuvering the controls. Pixhawk 2 Cube and Arduino Uno were used as flight and spray controllers, respectively, while Mission Planner 1.3.68 was used as the UAV sprayer’s ground control station. The result from the UAV sprayer’s field performance test revealed that its effective field capacity was 750 m2 per 10 minutes, and its application rate was 3.2 liters per 1,000 m2 of the field. Meanwhile, it was observed that its battery’s life was too short to cover at least a tenth of a hectare. Nonetheless, it was found that relative to the tank capacity and field capacity of the UAV Pesticide Sprayer, the one that was developed in this study was the cheapest, compared to the current price of UAV Sprayers in the market.
Drop test analysis of ball grid array package using finite element method
Authors: Gonzaga J , Ubando A T , Arriola E , Moran R L , Lim N R E , Mercado J P , Conversion A , Belarmino D
Published: March 2021

Proper design of semiconductors is the most essential step in ensuring electronic product reliability during manufacturing. The adoption of design optimization approach enhances the performance and reliability of the semiconductor package, hence, minimizes product failure. Semiconductor reliability especially in the application to automobiles is very crucial. High product failure tolerance in semiconductors in automobiles is required due to problems such as defects and malfunctions that are directly linked to casualty accidents. Such high tolerance requires keen quality control up to the semiconductor solder component level. This study aims to do a sensitivity analysis of the solder balls’ material properties and its effect on the stresses experienced by the semiconductor component with respect to its reliability using drop test. A drop test analysis was simulated wherein a shorter distance of 5 mm between the package and platform was implemented to make the simulation time faster. The density and modulus of elasticity of the solder ball material were identified as the independent factors while the stresses experienced by the BGA package during the drop test is the dependent variable. The results have shown that the maximum stress for all runs was found in the same area in the package. Changing the modulus of elasticity showed greater effect on the impact stress compared to the alteration of material density.
Evaluation of the integration of recycling unit in an iron manufacturing plant
Authors: Arriola E , Gue I H V , Ubando A T , Tan R R
Published: March 2021

Manufacturing of new steel from virgin iron ore is not only an energy intensive process but also generates a considerable amount of annual carbon footprint with respect to the world’s total carbon generation. It is actually considered as the highest carbon footprint generated among the heavy industries. Considering these characteristics of steel making, recycling technologies from scrap metal had been an area of interest in the circular economy framework. Production of new steel from scrap metals only requires as little as 10% of the energy used in the production of steel from virgin materials. This study aims to integrate a scrap metal recycling unit in an existing iron manufacturing plant using an optimization model that evaluates the carbon footprint. LINGO is used for the optimization model. The results have shown that carbon emission was reduced by 10.35% and significantly reduced one of the raw materials, coal, by 35.44%. The total power consumption was also reduced by 15.42%.
Exploring simplification methods in reducing simulation time for drop test analysis
Authors: Ubando A T , Gonzaga J , Lim N R E , Mercado J P , Arriola E , Moran R L , Conversion A , Belarmino D
Published: March 2021

- Automotive electronics can produce an unprecedented level of passenger comfort and optimized performance of engine and components. However, the increasing intricacy of these electronic devices makes them more susceptible to damage due to thermal loads, mechanical drops, and engine vibrations. While physical handling of automotive components is comparatively rare, the weight and complexity of specific components such as the ECU, power module, and sensor modules, makes any drop functionally fatal. Simulation approach is considered to be essential in solving these problems by minimizing costs and effort. This paper attempts to solve the issue of mechanical drops using an explicit dynamics finite element analysis solver. Moreover, simplification methods are applied to further minimize solution costs.
Influence of solar panel on wing aerodynamic characteristics of HALE UAV
Authors: Maliky Nu’man Amri , Moelyadi Mochammad Agoes , Amalia Ema
Published: March 2021

HALE UAV needs solar energy to maintain its flight in the day and night. The solar panel located on the upper surface may potentially affect aerodynamic characteristics of the HALE wing. The solar panel generates a heat resulted from solar radiation absorption and surface roughness which becomes parameters to be studied. To identify the phenomena of interaction of flow motion and the heat as well as the roughness, dimensionless numbers such as Reynolds Number (Re), Nusselt Number (Nu), and geometry reference (Ks/C) are used. The simulations for flows at the numbers are conducted using CFD method based on the solution of RANS equations. As a result, the heat transfer gives significant change in flow density near the surface which causes buoyancy effect and the change of flow velocity profile, while the roughness influences the flow characteristics disturbing the flow to become turbulent. They increase aerodynamic drag of 2.6 % and aerodynamic efficiency in the amount of 5%.
Object detection for drones on Raspberry Pi potentials and challenges
Authors: Khoi Tran Quang , Quang Nguyen Anh , Hieu Ngo Khanh
Published: March 2021

The paper presents preliminary research results about implementing an object detection program on a Single Board Computer. These results are used later to develop applications for drones. The object identification program is developed in Python using the TensorFlow library. The authors have succeeded in implementing and testing this object identification module using the artificial neural network model SSDMobileNet V2 on the Raspberry Pi 3B+. The results in this paper demonstrate the potential of this module for further development in the future. Based on the simulation and real-world results, the authors showed that a good outcome is achievable with limited resources for the AI module. Along with a high-precision object detection feature, this module can also estimate the distance and velocity of the “human” object with good accuracy. Besides, the paper also proposes several solutions to increase the performance and most importantly, the real-time feature of the developed module.
Velocity analysis of a six wheel modular mobile robot using MATLAB-Simulink
Authors: Fernando A , GanLim L
Published: March 2021

This paper presents the modelling and simulation of a six wheeled three body modular robot in MATLAB Simulink. The modules are modelled as an independent differential drive wheeled mobile robot. Velocity and distance were measured using three different configurations: two wheel, four wheel and six wheel configuration. The simulation result was able to predict the response of the modular body in different configurations in terms of velocity and distance with contact forces acting upon it.
Investigation of solution differences on natural convection in a tall cavity simulated by using the Boussinesq approximation and the real air density equation
Authors: Prasopchingchana Uthai
Published: March 2021

Solution differences of natural convection in a tall cavity filled with air in which the density of the body force term are approximated by using the Boussinesq approximation (BA) and by using the real air density equation (RE) are numerically investigated. The main parameters for the investigation are Nusselt numbers and numbers of cells in the multi-cellular flow. The investigation is carried out for the Rayleigh number of 104, and the cavity aspect ratio equal to 60. The temperature differences of the vertical cavity walls are varied from 1 K to 200 K. These conditions are appropriate to form the multi-cellular flow in the tall cavity obviously, and close to the boundary of the laminar and turbulent flows. Consequently, the differences in both Nusselt numbers and numbers of the cells in the multi-cellular flow can be easily observed. The finite volume method with the Lagrange interpolating polynomial (LIP) scheme are selected to discretize the governing equations of the flow, and the Semi-implicit method for pressure linked equations (SIMPLE) algorithm is used to determine the pressure field of the flow. The maximum difference of the average Nusselt numbers of natural convection in the tall cavity simulated by using BA and RE is 0.436 % for the range of the investigation. This indicates that the difference of heat transfer solutions of natural convection in the tall cavity simulated by using BA and RE is insignificant for practical applications, but there is an obvious difference on the numbers of the cells in the multi-cellular flow, when the temperature difference of the vertical cavity walls is greater than or equal to 120 K.