bluuebunny/crossref_metadata_2025 huggingface dataset:
Using decision rule in calibration of long gauge block on the conformity assessment scheme
Authors: Habibie M H , Hedrony O
Published: December 2019

Conformity assessment is a process commonly used in calibration activities to ensure the validity of the results of measurements or calibrations which is compared with specific requirements or standards. In this research the use of conformity assessment was carried out on long gauge block calibration activities in National Metrology Institute of Indonesia by determining objective criterion called decision rule. Decision rules are made by referred to JCGM 106:2012 standard that using two-sided acceptance method. In the two-sided acceptance method is used the acceptance/rejection limits such as: tolerance interval, acceptance interval and guard band. Conformity assessment result is stated as “accepted” if the calibration results are within the criteria of the decision rule, and vice versa. From this research, it was found that in the calibration process of long gauge block, the guard band value is obtained from the expanded uncertainty (U) value of the long gauge block (UUT). The conformity assessment results will be “accepted” if the reduced tolerance value (t
e
reduced) is greater than the measured deviation value (lx).
Impact of road rehabilitation zone on travel time to road user cost
Authors: Kalimanto D , Hadiwardoyo S P
Published: December 2019

Traffic movements in the city of Jakarta are linked to the Jakarta Outer Ring Road (JORR) Toll Road. This road network has a high traffic volume because it is integrated with other toll roads that connect other cities to Jakarta. The heavy traffic volume during the road rehabilitation will cause travel obstacles such as the increasing travel time to the long delay in traffic flow at the window time. The travel delay causes losses to road users. Road management must draw attention to the impact of the road rehabilitation zone to losses time by road users, especially on toll roads. This study analyzes the impact of speed changes in the work zone with two work areas. Traffic surveys have been carried out on the Jakarta Outer Ring Road (JORR) Toll Road section S using the roadpod metrocount tool. The results of this study show the increase vehicle operation costs by 169% to 206% due to a decrease in speed due to work zone. The results of this study are expected to be the consideration of road operators in determining the time in choosing of rehabilitation by minimizing the losses of time from the road users.
Reduces blade shaft deflection with improved mount design to increase vertical hybrid wind turbine performance
Authors: Erwin E , Soemardi T P , N Ikhsan M Y , Nugraha K
Published: December 2019

In a vertical hybrid turbine with a shaft bearing holder on one side, it has a shaft deflection problem that interferes with turbine performance. This study aims to improve the design of the turbine holder. The methodology used in this study is to analyse the deflection behaviour of the turbine when rotating. Next in the turbine design review, and the result is to increase the distance of the shaft holder bearings and increase the bearing diameter in the triangular frame. Deflection testing with the help of tracker software that’s able to measure deflection distance in one field when the shaft rotates. The results of the deflection comparison before and after the design improvement show a significant deflection reduction.
Investigation of mechanical properties on composite materials by several of severe plastic deformation (SPD) methods
Authors: Pramono A , Dhoska K , Alhamidi A , Trenggono A , Milandia A
Published: December 2019

The technology of severe plastic deformation (SPD) is the process on forming metals of large plastic strain that is used for mass production in order to make ultrafine-grained (UFG). Through research on the characterization of aluminium-based composite materials with several SPD methods, the ideal variable will be obtained in producing high-strength materials. The development of a new SPD method driven by requirements simplifies the process, so that it can be applied for mass production, some of the development of SPD technology is able to produce high plastic strain. The market for nanostructured materials produced by SPD technology is in sectors where superior traits such as specific strength is needed. This research is focused on a comparison of several SPD methods; APB, MAF, ECAP-PC and RPRF, in the scope of mechanical characterization on aluminium based composites. Result of mechanical properties obtained, the RPRF method is the best that is able to produce higher mechanical characteristics than other methods. That produces 75.9 VH10 hardness on RPRF, while APB 45.82 VH10, ECAP-PC 66.12 and MAF of 42.9 VH10
Study on the making of corrosion resistant steel (ASTM A36 Steel) coatings from a mix of graphene oxide + waterborne paint
Authors: Tjahjanti P H , Hidayat A R , Firdaus R , Iswanto  , Nurcahyo R , Fitri G A N
Published: December 2019

Steel coating as long as including ASTM A36 steel is generally carried out by galvanizing or coating to provide corrosion resistance. However, the problems that occur with the commonly used layer will break and peel off when the steel is removed. The purpose of this study is to make of corrosion resistant steel coatings especially for ASTM A36 steel from a mix of graphene oxide + waterborne paint. Weight loss method for calculate Corrosion Penetration Rate (CPR). Corrosion testing by immersing ASTM A36 steel samples in seawater (NaCl), and corrosion test for room temperature and 500°C. Final results showed that CPR values for ASTM A36 steel samples with graphene oxide + waterborne paint coating obtained CPR value that did not exceeded the allowable standard rate (0.5 mm/yr).
The study on mechanical properties of pack carburized low carbon steel using BaCO3as energizer
Authors: Negara D N K P , Widiyarta I M
Published: December 2019

Machine components such as crankshaft and gear require hard surface and ductile core characteristics. One method to obtained such characteristics is pack carburizing. This research concern to compare the mechanical properties of carburized low carbon steel under different carburizers; GBC (80% goat bone charcoal + 20% BaCO3) and BC (80% bamboo charcoal + 20% BaCO3) and derived from reference. Pack carburizing was carried out by heating up to a temperature of 950°C, holding for 4 hours and quenching in the oil. The results showed that hardness, yield strength, tensile strength and modulus elasticity of carburized steels increased significantly, however, there was a decrease in elongation. The closer to the core the lower of hardness obtained until reach a total case depth of 1.5 mm and 2 mm for carburized using BC and GBC, respectively. The use of carburizer GBC produces carburized steel with a higher yield strength (51.75 kg.mm−2), tensile strength (74.58 kg.mm−2), and elongation (5.78 %) than carburizer BC but lower in hardness (558.13 HV1), modulus elasticity (256.79 GPa), and effective case depth (0.33 mm). The mechanical properties of carburized low carbon steels have fulfilled requirements as the material of gear or shaft.
Forging process on gamelan bar tin bronze Cu-25wt.%Sn post casting deformation to changes in microstructure, density, hardness, and acoustic properties
Authors: Slamet S , Kusumaningtyas I , Suyitno
Published: December 2019

Casting and forging are a method of formation to produce gamelan instruments. This study aims to determine the effect of forging deformation on the as-cast gamelan bar to changes in the microstructure, hardness, density, porosity, and acoustical properties of the gamelan instrument. The research material was tin bronze Cu-25wt.%Sn. The casting process uses a sand casting method with a pouring temperature of 1100 °C. The forging deformation process was done by reheating the as-cast gamelan bar at a temperature of 600 °C. The thickness of the as-cast gamelan bar is reduced by 30% after the forging deformation process. The observations on the as-cast gamelan bar show coarse microstructure with large grains, inclusions, and increased porosity. The forged gamelan bar shows finer microstructure, elongated grain, α lamellar, α phase like a plate, and decreased porosity. The hardness of forged gamelan bar increased by an average of 30.3% VHN, density increased by 9,56% and porosity decreased by 95% compared to the as-cast gamelan bar. Acoustic properties show an increase in the natural frequency between the as-cast gamelan bar and the forged gamelan bar are 712.5 Hz and 1058 Hz.
Optimization of flotation columns to provide added value of local sphalerite ore
Authors: Oediyani S , Haryono D , Suwandana R F
Published: December 2019

Sphalerite is the most important mineral in the formation of zinc metal. According to regulation of Ministry ESDM No.5/2017 stated that the minimum grade of zinc concentrates to be exported is 51%. Therefore, it is necessary to do a beneficiation process for sphalerite ore to fulfil the requirements. Sphalerite is hydrophobic mineral, therefore it is the best way to processed sphalerite by flotation. Flotation is the process of concentrating valuable minerals from impurities based on the nature of the mineral surface. Column flotation is a flotation technology without an agitator as a producer of air bubbles like conventional flotation machines. Recovery is the most important factor in flotation and it shows the rate of acquisition of the flotation process. The purpose of this research was to determine the effect of air flow rates (2, 2.5, 3, 3.5, and 4 L / min.), percent solid (7.5%, 10%, 12.5%, and 15%), dose of reagent frother (10, 20, 30 and 40 ppm), and particle size of ore (-80 + 100 #, -100 + 140 #, -140 + 200 #, -200 #) on ZnS recovery. The research was carried out by using a laboratory scale flotation column with 4.6 cm in diameter and 150 cm column height. The flotation reagent used was activator (CuSO4), pH regulator (NaCO3), collector (PAX), and frother (dowfroth 1012). The highest recovery (90.29%) was achieved at a flow rate of 4.0 L/min, while on variation of particle size the highest recovery was 85.55% at (-100+140) #. The increase in percent solid or dilution of pulp is not always followed by an increase in recovery and the highest recovery ((71.26%) was achieved at 7.5% solid. In addition, recovery increases with increasing doses of frother, the highest recovery (86.04%) was achieved at 40 ppm doses of frother.
The characteristics of aluminum AC4B composites reinforced by the fraction volume variations of Boron Carbide through the stir casting process
Authors: Lestari A D D , Syahrial A Z
Published: December 2019

Aluminum AC4B composite reinforced with Boron Carbide (B4C) was made by stir casting. The characteristics such as toughness, impact strength, and tensile strength were determined. Aluminum AC4B acts as a matrix in the composite given the fraction volume variation of B4C reinforcing particulate of 1; 3; 5; 7; 10 %Vf followed by the addition of 5 %wt magnesium as a wetting agent, 0.04 wt-% of Strontium as modifier agent, and 0.15 %wt Al-5 Ti-1 B as a grain refinement agent through the stir casting process. The composites produced was charatcterised both microstructure by Optical Microscope (OM), Scanning Electron Microscope (SEM), link to Energy Dispersive Spectroscopy (EDS), and mechanical properties such as characterize each composite material such as tensile, hardness, and impact tests. The phases formed in the composite were α-Al, Eutectic Silicon, primary Mg2Si, binary Mg2Si, ternary Mg2Si, β-Al5FeSi, Al2Cu, Al3BC, dan AlB2. There is an increase in mechanical properties of AC4B/B4C compared to Aluminum AC4B base material, such as its tensile strength which reaches 149.032 MPa and its hardness reaches 49.3 HRB.
Development of biodegradable plastic made from recycling of polypropylene (PP) with corn stalks powder
Authors: Anggono A D , Darmawan A S , Wijianto  , Prasojo C
Published: December 2019

The objectives of the study are to develop biodegradable plastic composite and to investigate the mechanical characteristic and water absorption. It was made from polypropylene (PP) mixed with corn stalks powder. In this study, the weight fraction of polypropylene and powder was varied as 95% : 5%; 90% : 10%; 85% : 15%. For the water absorption test, the specimens were soaked in the water for 1, 7, and 14 days. The highest value of the tensile test was delivered from a specimen of 95% : 5% weight fraction. The tensile test of the soak specimen for 0, 1, 7, 14 days was obtained 17.41 MPa, 16.94 MPa, 16.11 MPa, 13.51 MPa respectively. The strain was 1.07, 1.19, 1.01, and 0.87%. The modulus of elasticity was 1686.74, 1500.42, 1712.1, and 1558.49 MPa. By adding the powder to the plastic, it was able to absorb water. The water absorption after 1, 7, and 14 days of water soak was 0.607, 1.468, and 4.651% respectively. The specimen of biodegradable plastic composites with a 95% : 5% ratio have compatible characteristics with commercial plastics and can be degraded easier than the origin plastic.
The effect of electrolyte concentration and electric current on the quality of surface colouring on anodized aluminium
Authors: Zulaida Y M , Ramadhanisa A H , Partuti T
Published: December 2019

The use of aluminium metal in daily life has widely used colouring techniques to enhance the aesthetic value of the metal. Aluminium anodizing process can produce porous on the metal surface. The formed porous can be used to store and hold the colouring agent to make them more durable. The research intends to observe the colouring characteristics on the aluminium surface influenced by several parameters of the anodizing process, including electrolyte concentration and electric current. In this study the current H2SO4 concentration was used as a variable to improve the quality of staining on anodised aluminium surfaces. The anodization process was carried out on H2SO4 electrolyte solution with variations in concentrations of 10% to 20% and the current density used was 3 A to 5 A. The tests were carried out using micro Vickers to observe the hardness value. The hardness was higher at lower concentration of electrolyte solution due to thinner layer of oxide film, scanning electron microscope to observe the structure and visual observations for anodised colour quality. From the results given, the tendency of the lower current density the size and density of porous lower. With the same condition, the colour was darker than higher current density.
Hardware and User Perspective Assessment on Application of Smart Door Access
Authors: Anshar Muh , Anas Nasri
Published: December 2019

Nowadays, applications of technology in various aspects of human life have been widely adopted. This increasing application relies on the degree of technology involvement, which supports an interconnected communication among resources available in the location. Smart room is a room equipped with technology where electronic devices contained in it can connect and communicate with each other so that it becomes a system that can be controlled thoroughly. One part of the smart room is the door. The door can be accessed using a variety of technologies. some of them are RFID tag technology, PIN code, Fingerprint technology, and Infrared sensor technology. This study discusses the satisfaction of smart room users about the time, distance and technology used. System 1 uses RFID tag technology, and Infrared sensor, and on system 2 uses RFID tag technology, PIN code, Fingerprint technology, and Infrared sensor technology. The time used is 10 seconds on system 1 and 3-6 seconds on system 2 is considered sufficient. The distance of around 3.5 -4.2 is also considered quite good and is also considered to be close. The use of RFID tag technology, PIN code, Fingerprint technology for incoming access and Infrared sensor technology for outgoing access is considered appropriate. Respondent satisfaction in system 1 was around 79% and in system 2 around 74%. System 1 is the most desirable technology, then system 2, then the door with conventional locking.
Influence of Tropical Environment on Electrical Properties of Electrical Insulation Materials
Authors: Manjang S , Kitta I , Gassing  , Sahali I R , Maricar F
Published: December 2019

The development of optimal electrical insulation materials in the tropics continues. One of the development models is to look for fillers that allow it to be mixed with insulating materials (polymers, ceramics, and glass). This study aims to obtain the properties of electrical insulation materials in the form of polymeric materials (silicon rubber) which are filled with fly ash (coal-fired power plant waste) so that it can be used as a high-voltage electrical insulator. The activity that has been carried out was testing the performance of electrical insulating materials filled with fly ash under conditions under high electric fields and tropical environments. The research was conducted at the Electrical Engineering Building, Hasanuddin University, Makassar City, Indonesia. The performance evaluation of electrical insulation materials (silicon rubber plus fly ash) refers to the results of measurements of water diffusion characteristics and relative permittivity characteristics. The results of the study were in the form of information about the feasibility of coal-fired power plants to be used as fillers for electrical insulators in tropical environments. The results of this study are Fly ash added to silicone rubber to improve the electrical properties of the insulating material.
Temperature and Salinity Gradients Analysis for a Solar Pond Prototype
Authors: Muslimin Z , Gunadin I C , Anshar Muh , Siswanto A
Published: December 2019

In this study, a solar pond prototype is used to analyze the temperature and salinity gradients of alternative energy source processes. The study used two types of solar pond to investigate the temperature and salinity of gradients from each solar pond. The first solar pond utilizes sunlight as a heat source that emitted directly on the solar pond and the second solar pond utilizes the spotlights as a direct heat source emitted on the solar pond. The first solar pond is made of a cylindrical plastic tank of 1.05 m tall, 0.8 m in diameter placed outdoors in direct sunlight and the second solar pond model is made of a trapezium plastic tank with a height of 0.9m, the upper diameter 0.54m and a bottom diameter of 0.49m placed indoors with floodlights. The gradient temperature salinity and temperature measurement in the fest solar pond are smaller than temperature in the second solar pond however, the T3 temperature in the outdoor solar pond is larger than the indoor solar pond. The observation results show that the first solar pond generates the mean value of temperature and salinity of successive gradients 32 (°C); 30 % and the second solar pond has the average value of temperature and salinity of successive gradients 31 (°C); 28 %.
Insertion of 275 kV Transmission Line for Improving the Voltage Profile and Efficiency of Electrical Power System
Authors: Kitta I , Manjang S , Sahali I R , Maricar F
Published: December 2019

The location of electricity generation generally lies in the centers of renewable energy sources which are generally far from urban centers, such as in the province of South Sulawesi, Indonesia. This condition becomes a separate issue related to the quality of the voltage and the efficiency of the electrical system that uses 150 kV transmission lines to transmitted electrical energy from the power plants. Therefore, to avoid waste and lack of quality electricity, it is necessary to insert a new transmission line from these power plants to the city of Makassar. Where the transmission line built is 275 kV transmission line because it increases the voltage profile and is efficient compared to 150 kV transmission line even though the network is added to the bank’s capacitor. Therefore, this paper shows the reasons why a 275 kV transmission line was chosen for the improvement of voltage and reduction of power losses in South Sulawesi system.
Environmental Sensor Design Prototype for Genset Backups Power at Ground Station and Data Centers Based on Internet of Things Devices
Authors: Hidayat A , Ramadhan P R , Zainuddin  , Zainuddin H
Published: December 2019

Earth station and data center devices require stable backup power. The remote sensing earth station has 2 generators that can operate simultaneously or alternately. This Generator Set has optimal ability to work at room temperature up to 50 degrees Celsius. This environmental sensor prototype consists of three main parts: temperature sensor, ESP wifi module and website to display updated information at any time. The generator set system is only able to work under room temperature 50 degrees Celsius, if the room temperature exceeds 50 degrees Celsius the system will turn off the generator. This sensor system is used to monitor the room temperature so that it is not more than 50 degrees Celsius. All of the above systems can be accessed through the Local Area Network within the Parepare Remote Sensing Earth Station. With this system is expected to natural disturbances that occur in the antenna can be minimized so that the antenna ability to track and data acquisition can be maximized. The end of this prototype sensor is expected to help extend the life of antennas operating in the remote earth station LAPAN Parepare.
Indonesian Sign Language Letter Interpreter Application Using Leap Motion Control based on Naïve Bayes Classifier
Authors: Ridwang  , Syafaruddin  , Ilham A A , Nurtanio I
Published: December 2019

Most deaf children are born into hearing families and the majority do not begin their Sign Language learning before age 3-6 in school. As children learning Sign Language from infancy show higher language proficiency than those who do not, it underlines the importance of hearing parents learning how to sign. The recent innovation in the technology and introduction of new gesture control based devices, like leap motion controller. Technology that can track finger and hand gestures accurately at very low cost. The research method in Naïve Bayes algorithm, in order to classify 26 alphabet letter of Indonesian sign language including letter J and Z which using gesture for describe it. The Leap Motion controller is a consumer gesture sensor aimed to augment a user’s interactive experience with their computer and it was utilized as an interface for hand motion tracking without the need of wearing any external instruments. It use for derive feature data from the deaf children gesture recording to set data in application. The accuracy level of the test result reached 96%.
Cloud Classification Based on Images Texture Features
Authors: Nurtanio I , Zainuddin Z , Setiadi B H
Published: December 2019

An identification of cloud imagery is part of the cloud observation process which is very important to know the potential for weather changes, especially in the Sultan Hasanuddin airport area. The purpose of this research is to build an artificial intelligence model to identify and classify texture patterns of cloud images. The research used 80 clouds images data contained in the Sultan Hasanuddin Airport area. The data consist of four types of clouds, Altocumulus, Cirrus, Cumulonimbus and Cumulus. In this research, a feature extraction process using Gray Level Co-occurrence Matrix (GLCM) algorithm and Support Vector Machine (SVM) is used for the classification process. We used a set of 4 GLCM features. The 4 selected features are contrast, correlation, energy and homogeneity. Training and testing data using cross validation method with three stages validation. The highest level of accuracy is found in the third stage validation with an accuracy value of 85%.
A Study for the Application of Steel Frames on a Traditional Wooden Fishing Boat
Authors: Bochary L , Firmansyah M R , Sitepu G , Asri S
Published: December 2019

As its main material, specific timbers for supporting boat structure are required in the construction of traditional wooden fishing boat in Indonesia. The requirements for the specific timbers are vary such as it must be water resistant for ship skin planking and must be in the specific form for the boat frames in which the curvature will be different according to the specific curvature of each transversal boat section along the boat length. Currently, the required specific form of timbers for the boat frames are becoming difficult to be acquired especially in the midship area of the ship which requires extreme curvature. The difficulty to acquire the specific curvature form of frames as required have threaten the sustainability of wooden boat construction process in Indonesia. Hence, an alternative material for replacing the wooden material for boat frames is needed. The requirements for the alternative material are as follows; it must be easy to be formed according to the boat transversal section form along the boat length and must be strong enough to support the strength of the wooden boat hull. This research is conducted in order to analyse the feasibility of steel frame application for replacing wooden frame in the construction of traditional wooden fishing boat. Some alternatives of different steel frame dimensions with specific profile forms are analysed to determine the appropriate steel frame construction for certain type of wooden fishing boat. In the end, a recommendation of the steel frame dimensions for replacing wooden frame on a certain traditional wooden fishing boat is proposed.
Simulating Torque Converter on a 3 GTs Fishing Vessel using Computational Fluid Dynamics
Authors: Zulkifly  , Baharuddin  , Rivai H , Firmansyah M R , Santoso T M
Published: December 2019

Torque converter is needed to reduce the difference distance on an engine power curve and propeller operating load curve. Torque converter works by removing and cutting the flow of power from engine to transmission shaft automatically in order to adjust with fluctuative propeller load. Torque converter works on a fluid clutch principal hence it has ability to absorb and reduce excessive torque moments. This research aims to determine the effect of impeller distance against dynamic characteristics of torque converter on a 3 GT fishing vessel. Based on the designed torque converter dimension, a simulation using computational fluid dynamics (CFD) in an ANSYS 16.0 simulation software was conducted. The simulation was done on three distances between impellers i.e. 2.5 mm, 5 mm, and 7.5 mm and on five rotations i.e. 600 rpm, 1000 rpm, 1400 rpm, 1800 rpm, and 2200 rpm. Information obtained from the CFD simulation includes: pressure and shear stress distribution on impeller, flow velocity on the torque converter shell, torque value, as well as maximum transmission power of torque converter. The result shows that the ideal impeller gap for the 3 GTs fishing vessel from the dynamic characteristics parameter of torque converter is 7.5 mm.
Investigation on Reflected Wave by Different Geometrical Ramp Shape of Overtopping Break Water for Energy Conversions Using Experimental and Simulation
Authors: Roslan M F , Ahmad M F , Musa M A
Published: December 2019

Innovation trends on the development of breakwater have prolong its functionality from coastal protection to harness wave energy. One of the latest structural being study is the overtopping breakwater for the energy conversion which integrate breakwater with wave energy converter. An impact of linear ramps on reflection of the structural been studied in detail in some previous researches and create opportunity in exploring vast scope of study including the ramp shape. Therefore, intention of this study is to experimentally investigate the effectiveness of various geometrical ramp shapes of the structural toward the reflected wave. In addition, simulation was conducted and compare with the experimental result to ensure the agreement of the outcomes. This study used different wave parameters and effect of relative depth (Hm0/h) to acquire data on the behaviour of the reflected wave that describe the effectiveness of the structure. The findings of this study in the experimental work indicates that the cubic ramp shape precedes the linear ramp with 21.5% more efficient under certain wave conditions. Besides, this study additionally reveals similarities in both methods and conclude that ramp shape has significant influence on the reflection of the wave from the structure and the highest percentage of discrepancy for the CFD is 22.3%. However, the contribution of the different ramp shape is absent at the maximum depth but significantly affect as well as the depth decrease.
Performance Comparison Between Ellipse and Circular Intake Shapes of Propeller Flow Cooling System (PFCS) with Numerical and Experimental Methods
Authors: Mahmuddin F , Ramadhan S , Fitriadhy A , Klara S
Published: December 2019

This research carried out an analysis on the use of high pressure flow behind propeller to cool the ship main engine known as Propeller Flow Cooling System (PFCS). The system is commonly found on relatively small fishing boats at South Sulawesi area of Indonesia. Using the system, the special pump for engine cooling purpose is not needed. The present research conducted an investigation on PFCS intake shape that would be optimal for delivering water to main engine which was arisen from the propeller rotation and to find the difference of water capacity produced from different shapes of intake. The implemented research methods were numerical and experimental methods that analysed the shape of two intake shapes namely, circular and elliptical shapes. In numerical computation, ANSYS CFX software was adopted. The result from numerical computations was an initial prediction to the tendency of the results. In order to verify the results, an experiment in a tank facility known as Circulating Water Channel (CWC) tank was conducted. In the experiment, measurements were performed at 2 (two) different locations which were at the center of propeller and at 0.7R of propeller blade. The results of the research found that the performance of the elliptical intake shape is more optimal compared to the circular one.
Design of Software for Calculation and Analysis Engine Propeller Matching
Authors: Habibi
Published: December 2019

The criteria of a good ship are not only could floating in the sea, but it should have a very complex construction development planning. Longitudinal and transversal strengths, stability, flood, bulkhead, ship motion etc. were interrelated criteria that should be calculated for safety and comfort of the ship, passenger and cargo passenger. Matching point is an operating point of main engine same with the load character of propeller. In another word, the operating point of main engine rotation, where absorbed power by propeller is equal by produced power by main engine, and delivery equal speed with planned service speed. One step in ship design evaluating is EPM (“Engine Propeller Matching”). The lack of available software to analyze relationship between characteristics of propeller with main engine and hull, causing the calculation of EPM (Engine Propeller Matching) takes more time. Java is a very popular application, especially for enterprise application. So, that Java applications can be used to build a programming language of Engine Propeller Matching.
An Evaluation of Carrying Capacity of Jack-in Piles with Base Enlargement in Soft Clay
Authors: Aponno G , Sholeh M
Published: December 2019

The enhancement of the carrying capacity of the single pile can be achieved by improving the roughness of the pile shaft and/or enlarging the tip of the pile. This paper presents the results of a laboratory experiment of a modeled steel pipe pile with and without the enlargement of the pile base. The pile base was made separately from the pile shaft and was inserted using jacking pressures into an artificial and homogenous soft clay soils. The soil media used is classified as high plasticity clayey-silt is compacted in the concrete container with 600 mm in diameter and 1000 mm in depth. This study shows that the technique of pile tip enlargement works properly, and the carrying capacity of the pile is higher than a pile without base enlargement by increasing of up to ± 270%.
Optimization of Coagulation-Flocculation Process for Tello River Water Treatment Using Poly Aluminum Chloride and Aluminum Sulfate
Authors: Widiyanti S E
Published: December 2019

Tello River Water was utilized by PT. PLN SULSERABAR as Boiler feed water. Total Suspended Solid (TSS) in river water can be removed by the coagulation-flocculation process. Improved performance of coagulation process can be done by optimizing coagulant concentration and pH on coagulation. This research focused on optimization of pH and percent (%) removal of TSS using Poly Aluminum Chloride (PAC) and Aluminum Sulfate (Alum). The concentration of coagulant was 25% of the initial TSS of the sample for PAC and 35% of the initial TSS of the sample for Alum. The sample used in this research is Tello River Water which has initial TSS concentration of 195 mg/L with rapid mixing (350 rpm) for 1 minute, slow mixing (50 rpm) for 20 minutes and 30 minutes of sedimentation. The coagulation-flocculation process was carried out in the pH range of 4-10 and the TSS concentration was analyzed using the Gravimetric method. The optimum pH on coagulation and percent (%) TSS removal obtained from this study were 7, 99.23% for PAC and 6, 89.48% for Alum. These results indicated that PAC was the perfect coagulant for the removal of TSS because it was able to eliminate TSS nearly 100%.
Tidal Flood in Pekalongan: Utilizing and Operating Open Resources for Modelling
Authors: Pratama M B
Published: December 2019

The open resource materials are used in this research to construct a numerical model and study the tidal flood in Pekalongan City, including the impact of land subsidence. The area of interest is in 6 villages in the north coast of Pekalongan namely, Jeruksari, Pabean, Bandengan, Kandang Panjang, Panjang Baru, and Panjang Wetan. Delft3D, an open ware, is used for numerical modelling. While the input data are obtained from GEBCO for bathymetry, SRTM for topography, and TPXO for tidal constituent. The resulting model shows a decent agreement with field tidal elevation data from Indonesian Navy Tide Tables and GLOSS. After applying the annual land subsidence, compare to flood in May 2018, it is found that the inundation height increases for around 11, 36, and 132 cm in 2019, 2025, and 2050. In 2050, an extreme inundation over 2.5 m is found. Similar with Jakarta flood, to protect the land area, coastal dykes may be proposed. However, for long-term resilience, it is recommended to emphasize efforts in decreasing the land subsidence rate. This study indicates the threat of tidal flood in Pekalongan, thus further studies followed with field survey and more constituents in the modelling are strongly recommended.
Flexural Strength Test For Concrete Beam With Mild Steel and Reinforcing Iron
Authors: Umar M Z , Faslih A
Published: December 2019

Mild steel in buildings tends to only be used as a roof frame. The phenomenon in the field that lightweight steel roof truss can be combined with mortar mixture. In general this union is found on the walls of the construction of the red stone horses. This phenomenon is captured and applied dynamically, creatively, and innovatively with new idioms. Mild steel can be used as a beam reinforcement. This research is important in order to find alternative reinforcement of beams other than iron and strong beam reinforcement. This study aims to determine the ratio of flexural strength between concrete from mild steel reinforcement and concrete from steel reinforcement. This study uses a concrete flexural strength test and simple test beam method. The test beam is loaded and centered directly. Press testing machine is used as a flexural test device. The machine is equipped with two support beams and one load beam, load construction, and support blocks. Six beams are used as specimens. Test objects are made of different reinforcement. Concrete beams are made from a cross section of 600 mm x 150 mm x 150 mm, used reinforcing iron diameter of 6 mm, and amounting to three (first test object). Concrete beams are made from a cross section of 600 mm x 150 mm x 150 mm, mild steel is used with the profile shape C73.35.10 mm, and there are three pieces (second test object). This study concluded that the test beam was made from a cross section of 600 mm x 150 mm x 150 mm. and mild steel (profile C73.35.10 mm) has twice the maximum flexural strength compared to 600 mm x 150 mm x 150 mm cross section beam and reinforcing iron (6 mm diameter).
Subsurface Investigation of Freshwater-Seawater Interface on Gowa-Takalar Coastal Aquifer, Indonesia
Authors: Ramli M , Purwanto  , Anas A V
Published: December 2019

Gowa-Takalar Coastal Aquifer is an unconfined aquifer located in the southward of Makassar City. The Gowa-Takalar area has a heavy groundwater exploitation particularly on dry season. In this area, the groundwater is utilized to support water need for agriculture activities, marine tourism facilities, and new settlement development. The highly economic activities in this area, it causes an intensive groundwater exploitation. Since this area is located around coastal area, this area has highly susceptibility to suffer from seawater intrusion. In order to maintain the continuity of groundwater supply, a special study is needed on hydrodynamics of fresh-sea water interface as the basis for the formulation of a sustainable management model. This study as an early step of groundwater management research emphasizing on basic of aquifer and groundwater data. The research method consisting of reconnaissance study for geological & hydrogeological mapping, groundwater chemistry laboratory analysis, and geo-electrical investigation. Geological condition of this area is composed of alluvial and coastal deposits, volcanic deposits, and marine sedimentary rocks interbedded with volcanics. These materials form three hydrogeological characteristics: extensive and moderately productive aquifer, locally productive aquifers, and poorly productive aquifers of local importance. The chemical composition of groundwater from dug wells show the chloride concentration vary from 3.55 ppm to 81.65 ppm, with chloride-bicarbonate ratio is 0.008 – 0.035 indicating aquifer without sea water invasion. However, based on vertical electrical sounding, the resistivity layers vary from 0.02 to 62.50 ohm-m indicating the present of seawater intrusion into coastal aquifer.
Chemical Characteristics and Correlation of Heavy Metal Elements in Lumpue Beach, Parepare City
Authors: Sirajuddin H , Tonggiroh A
Published: December 2019

This study aims to analyze heavy metal elements in Lumpue Beach. Characterization of Lumpue Beach sediments in addition to the megaskopis and petrographic observation approach, determination of mineral chemical aspects using ICP-OES analysis was also done. This analysis done on 7 samples of very fine sand obtained from sieving and aimed to determine the level of heavy metal elements on the ppm scale. Based on ternary plotting diagrams, that the dominant Lumpue Beach is composed of sedimentary texture very fine sand - coarse sand. The ratio of Pb elements in the study area has an average level of 41.38 ppm and a trend line R2 = 0.25, Cd has an average level of 1.65 ppm and a trend line R2 = 0.12, Cu elements has an average level of 14.5 ppm and a trend line R2 = 0.02imes and Zn element has an average level of 62.125 ppm and a trend line R2 = 0.0022. They are indicated to exceed normal limits. Based on the use of Pearson method with two paired variables on metals Cu, Fe, Ni, Zn, Pb, Ti and Mn, it is known that Cu metal has a very weak correlation with Fe, Zn, Ni, Pb and Ti, while Fe metal has a strong correlation to Zn., Ti and Mn but have a weak correlation with Ni and Pb. Fe and Al metals are deposited with low values, this occurs in the concentrations of the two metals and follows the sediment fraction controlled by currents and tides.
Local Wisdom that forms of the Bajo Ethnic Settlements in Belopa Village
Authors: Ali M , Ramadhani A M , Ekawati A S
Published: December 2019

In general, the characteristics of the Bajo ethnic (Bajo) settlement are built on the waters. Likewise with the Bajo in Belopa Village, their settlements were formed starting above the waters. But along with the development and increasing population, their settlement pattern increasingly leads to land. So that, the arrangement of the settlements began to differ from its characteristics. This condition is feared to have an impact on local wisdom, which will gradually disappear. This study examines the extent of local wisdom that underlies the formation of Bajo settlements in Belopa Village. The analytical method used are descriptive analysis, comparative analysis, spatial analysis and photo pmpping analysis. The results of the study show that there are several forms of local wisdom that underlie the creation of Bajo, namely governance, value systems, procedures, and special provisions. In addition, it was also found that the condition of the settlement of the Bajo that currently exists has characteristics based on orientation patterns and material and type of building. The condition of the Bajo settlement facilities and infrastructure, some of its associations still cannot serve the needs of the community and its maintenance is still not optimal.
Effects of Work on Shock Absorber and Spiral Springs Against Vertical Loads of Vehicles Burdening the Road Structure
Authors: Ka’ka S , Himran S , Renreng I , Sutresman O
Published: December 2019

This research aims to examine the effect of vertical dynamic load of vehicles and changes in dimensional barriers on the road surface in its path. Experimentally this fluctuating load is replaced by a pneumatic force change based on the regulation of air pressure on the regulator. The deviations generated by the varying load work are measured by placing a proximity sensor along the spring movement. The amount of vertical load transformation reaches the road surface is measured by using Load cell. Characteristics of vertical dynamic vibration occurring due to several dimensional barriers, U (cm) obtained using mathematical modelling method with 2 DOF suspension system transfer function. The results showed a condition on the body and wheels of vehicles experienced a brief overshot for 0.14 seconds with deviation of 0.178 m. From the graph shows that the rate of deviation that occurs is large enough that Y2d = 1.03 m / s caused by a sudden shock that occurred on the wheels of the vehicle. This condition does not last long that is only duration t = 0.22 s, because the spring reaction force and shock absorber can absorb 45% vibration against the sprung and un-sprung vertical load of the vehicle.
Recent Progresses on the High Molecular Polymer of Lactobacillus Extracellular Polysaccharides
Authors: Xing Yanxia , Zhu He , Chang Guifang , Yu Kexue , Yue Fengli
Published: December 2019

Lactobacillus-extracellular polysaccharides (LAB-EPS) is a natural high molecular polymer with various functional properties, such as improving fermented milk texture and improving human health. Many scholars have carried out extensive and in-depth research on the structure, functional properties and structure-activity relationship of lactic acid bacteria extracellular polysaccharides, yet lacking systematic summary on the relationship among LAB-EPS types, chemical composition, structure and nutritional functions. This paper sorts out the research progress in this field and provides reference for further research and development.
Combination of LMS Algorithm in Adaptive Noise Cancellation System
Authors: Wei He , Shao Lanchun
Published: December 2019

In the adaptive noise cancellation system, the traditional fixed step size LMS algorithm is used to filter the noise signal, but the noise signal cannot be completely cancelled out. In order to realize the two-stage filtering, this paper proposes to combine two fixed step size LMS algorithms and to combine a fixed step size LMS algorithm with a variable step size LMS algorithm based on Bessel function. The combinations of different LMS algorithms are applied to the adaptive noise cancellation system, and the MATLAB simulation experiment is performed on the noisy signal. Theoretical analysis and simulation results show that the two-stage filtering realized by combination of different LMS algorithms is obviously better than the one-stage filtering realized by a single fixed step LMS algorithm, and the performance in terms of fast convergence speed, tracking speed and steady state error is improved.
Research and Development of Embedded Experiment Box Based on PSOC Technology
Authors: Li Ruilin , Li Honghong , Yu Jinhua , Xiong Pingping
Published: December 2019

With the continuous development of science and technology in recent years, chip technology is also developing rapidly. Embedded technology is a new development of computer application technology with a wide range of application fields and development prospects. With the successful development of PSOC chip technology, it can be effective. The improvement of analog-to-digital conversion, digital-to-analog conversion, display, key operation, pin input and output, etc. for overall design and hardware implementation and software implementation, so research and development of a new type of experimental box is also very helpful, the experimental box can effectively improve The function and rate of code decoding and waveform transformation have a significant effect on the teaching of universities.
Application of SPT on SA-335P91 Steel Used For High-Temperature Components of Utility Boiler
Authors: Liu Jie , Ning Bai Bai , Yu Jianming , Qian Gong , Che Chang
Published: December 2019

To further develop the application of SPT in the life assessment for high-temperature components of utility boiler, this paper analyses the microstructure of the common steel of SA-335P91 with the treatment of high temperature aging by OM, SEM, EDS and XRD, tests the normal tensile properties and the mechanical properties from SPT, and studies the relationship of the two kinds of mechanical properties. The results shows, after high temperature aging with 630-640°C×3000h of SA-335P91 steel, the size of precipitate in the microstructure grows from small to big, the number from many to a few, the distribution from grain inner and boundary to only boundary, and the tensile strength and yield strength of materials display the downtrend. More than ever, the experiments demonstrate the SPT is scientific, reasonable and feasible in non-destructive testing and the life assessment of SA-335P91 steel using in utility boiler, and the two fitting formulas are: σ
s=0.5398Py
/t2–49.456; σb
=0.0732P
max/t0
2 +105.59.
Method for Determining Maintenance Interval of Gear Reducer Based on Preventive Sequential Maintenance
Authors: Xiang Nan , Huo Lin , Zhang Yanqiang
Published: December 2019

With the continuous development of society, maintenance work has been paid more and more attention in the production field. As one of the indispensable components of many production equipment, the gear reducer can effectively guarantee the safe operation state and maximize the efficiency of the production process through preventive maintenance. This paper constructs a preventive maintenance strategy for gear reduction gearboxes through the analysis of preventive maintenance decisions. Compare the two methods of regular maintenance and sequential maintenance to determine a more practical method. Then the method is verified by an example and the conclusion is drawn.