bluuebunny/crossref_metadata_2025 huggingface dataset:
Individual-Based Simulation for Online Marketplace Diffusion among Batik Small Medium Enterprises (SMEs) in Indonesia
Authors: Saptadi S , Sriyanto  , Pangaribuan B M
Published: September 2019

The number of Batik SMEs and internet users today in Indonesia has increased This condition prompted the government to create a program of 8 million SME program to go online in 2019. But, until 2017 only 45% of the total targeted SMEs go online. This condition raises the need to understand the behaviour of SMEs implementing internet technology. The research focuses on UKM Batik and the online marketplace (OM), where batik is a unique commodity of Semarang City and OM is the implementation of emerging internet technology. The factors of OM adoption are adopted from a comprehensive T-O-E Framework. These factors form the basis for agent-based model development. Agent-based models that describe the behaviour of SMEs individually show the results of this study. Only 6 of 20 factors are used in the simulation model. These factors are the level of SME understanding that OM can increase the number of company sales, the level of SME understanding that OM can expand the company’s marketing and sales area, the cost of implementing OM, the hardware readiness of SMEs, the level of courage of SME trying new things and the experience of SMEs in using OM.
Simulation of Mitsubishi RV-M1 Robotic Arms by Using MATLAB® for High School Teaching
Authors: Prabowo D , Wiannastiti M , Hedwig R
Published: September 2019

Since most of high school students in Jakarta love robots very much, they join Engineering Club at school. Unfortunately, only few high schools have a real robot arm for students to learn in their school labs. The purpose of this research is to create a small simulation program based on MATLAB® and Robotic Toolbox 9.10 which resembles Mitsubishi RV-M1 robotics arm. The simulation is a 3D view and 5 degree of freedom which its end-effectors position is as close as the real one. It is hoped the results of this research study can be used as a base for further development of human controlled robotics arms simulation.
The Identification of Variables of Quality Influence Mobile Location-Based Service (m-LBS) (A Case Study: Go-Food Services in Semarang City)
Authors: Puspitasari N B , Budiawan W , Hurisandi V
Published: September 2019

Mobile Location-Based Service (m-LBS) is a rapid growing increasingly business type in many countries including Indonesia. One of the large companies in m-LBS business is Go-Jek, in which one of the most widely used service features is Go-Food. In its development, there are many competitors of Go-Food, so Go-Food has to improve its service quality in order not to lose the customers. Based on the preliminary studies, they show that the customers are less satisfied with the quality of Go-Food services. The purpose of this study is to determine the variables affecting the quality of Go-Food services as a whole. The data collection is obtained through the distribution of online questionnaires with the respondents of Go-Food customers in Semarang City. The data collected in this study is 306 respondents, in which this data is then processed by Partial Least Square (PLS) by using SmartPLS 2.0 software. The result of this study indicates that the predicted variables affect significantly to the quality as a whole that the customers feel toward Go-Food services in Semarang City, which are Information Quality with the influence of 14.04%, Driver Reliability 11.04%, Assurance 11.93%, Localization 10.57%, and Design Quality 10.53%. The better quality of the variables, so the better quality level of customers feeling toward Go-Food services in Semarang City. Therefore, the variables are analyzed to give the recommendations to improve the quality of Go-Food services in Semarang City.
Starting The Implementation of Risk Management in a Higher Education Institution: The Case of IPB University
Authors: Priyarsono D S , Widhiani A P , Sari D L
Published: September 2019

This paper shares an experience of implementing risk management in a public university in Indonesia. The shared experience is focused on the triggers for starting the implementation, the critical first steps, and the strategy or approach utilized in the implementation. One of the remarkable findings is the importance of human resource development as a necessary step in the implementation. Another important approach is the pilot project, i.e., instead of implementing parts of risk management system in all units of the organization, the approach takes a limited number of organization units to implement the whole risk management system. The findings are then internationally compared with reports of risk management implementation in other universities. Several recommendations concerning risk management implementation and topics for future research are provided in the concluding remarks.
Implementation of PDCA Cycle in Calibration and Testing Laboratory Based on ISO/IEC 17025:2017
Authors: Habibie M H , Kresiani R H
Published: September 2019

ISO/IEC 17025:2017 is aninternational reference standard for calibration and testing laboratories to improve their competence, to promote confidence in the operation of laboratory, and to generate valid results. Implementation of ISO/IEC 17025:2017 is also related to the implementation of ISO 9001:2015 standard which contains a process-based PDCA cycle (Plan-Do-Check-Act). The PDCA cycle is commonly used in terms of improving quality of services that is in line with the objective of the implementation of ISO/IEC 17025:2017. Therefore, this research discusses the concept of PDCA which is used in ISO 9001:2015 based on ISO/IEC 17025:2017’s clause to provide convenience in understanding the implementation of ISO/IEC 17025:2017in the transition period. This research is conducted by reviewing clause by clause on ISO/IEC 17025:2017 standard which is connected with PDCA concept. The result of this research is obtained PDCA model which contains clauses on ISO/IEC 17025:2017 standard accompanied by its implementation in calibration and testing laboratories
Designing of Raw Material Scheduling Supply Multi On Supplier Strategies with Price, Lead time, And Stochastic Demand Variations. Case Study: Electricity Manufacturer
Authors: Amelia P , Ridwan A Y , Santosa B
Published: September 2019

Raw Materials are one of the important things in manufacture. The availability of these items is very important for the production process to take place. The researcher will research an electricity company. The electricity company produces electricity equipment. The four types of electricity equipment are cartridges, thermocouples, tubular and mica heaters. Some of them have stochastic demand. Each of them has three components of the same raw material and used to make the product. However, the company cannot fulfil the demand because raw materials are not available, so consumers are looking for items elsewhere. This delay occurred because of the delay in sending raw materials, so the company has to wait until the ordered items arrive. This problem is being more complicated by the differences in parameters for each supplier such as price differences and lead time of arrival. Therefore, the company must determine the optimum scheduling and safety time by minimizing inventory costs as a result of Mixed Integer Linear Programming (MILP) being used in resolving these problems.
Psychosocial Risk Factors for Musculoskeletal Symptoms of Construction Workers
Authors: Kusmasari W , Yassierli
Published: September 2019

Several previous studies have stated that there are several risk factors that affect musculoskeletal disorders on construction workers. Most of the studies have reported the existence of individual and physical risk factors, but only few studies have focused on psychosocial risk factors. The present study included 45 construction workers of a building construction project. A self-reported measurement questionnaire was used to determine the prevalence of musculoskeletal symptoms. The results showed that shoulder pain was most felt by workers during the last seven days and the last 12 months. Regarding to the prevalence felt during the last seven days, factor of reward was significantly associated with knee pain (OR: 0.09; 95% CI: 0.01-0.99). Regarding to the prevalence felt during the last 12 months, factor of weight was significantly associated with upper back (OR: 1.11; 95% CI: 1.01-1.22) and shoulder (OR: 1.09; 95% CI: 1.00-1.18). Body mass index was significantly associated with upper back (OR: 1.35; 95% CI: 1.01-1.22) and shoulder (OR: 1.31; 95% CI: 1.01-1.71). Results of this study indicated that psychosocial risk factors have significant roles in developing musculoskeletal disorders.
An Inventory Management Model for Product-Service System in Dual-Channel Supply Chain
Authors: Widodo E , Sitohang E A G , Vanany I
Published: September 2019

This paper proposes a model to study inventory management for product and service bundles under product-service system (PSS) concept. This bundle is offered to customers under the dual-channel supply chain (DCSC) structure. By PSS concept, it is expected that the products sold will increase, then the products or services that are not selling well can be bundled with goods that sell well, so as to reduce overstock or deadstock in the inventory. In terms of distribution, using the DCSC structure, sales can increase by 20% from the previous one. This research will be conducted by combining the PSS concept in the DCSC distribution structure, in terms of inventory management. Model is developed of inventory cost minimization for DCSC-PSS by considering order quantity as a decision variable. Afterwards, the model will represent two scenarios of game theory for decision making practice DCSC-PSS, Stackelberg Leadership and Vertical Nash. The initial result of the numerical experiment was DCSC’s total inventory cost, Stackelberg Leadership scenario is IDR 556,642,465.40 greater than Vertical Nash, IDR 468,614,127.10. Afterwards, sensitivity analysis based on customer acceptance (ρ) and percentage of PSS (φ). At last, it was concluded that Vertical Nash was better than Stackelberg Leadership for decision making in inventory management
Financial Strategy Model for Social Health Insurance in Indonesia using Simulation
Authors: Kurnianingtyas D , Santosa B , Siswanto N
Published: September 2019

Social Health Insurance (SHI) in Indonesia is still facing many obstacles, especially the financial aspects from 2014 to 2017 due to the SHI financial losses that has received more attention from the public and the government in Indonesia. Therefore, this study intends to provide financial strategy recommendations that will get a stability revenue over cost. Dynamic system simulation approaches are used to obtain optimal financial strategies that take into account variable costs and income decisions. The parameter of the load variable is medical costs while the income variable is obtained from the participant premium rate factor. The data come from 2016 and 2017 related data to membership, especially PBPU (Participants Not Wage Recipients). Then, the equation used to find the right strategy is Income ≥ Expenditures. In conducting simulations, scenarios are designed to reduce the level of financial losses that occur in SHI. The scenario of this research is a scenario that changes the parameters of premium rates and benefit costs. The combination of medical cost and premium scenarios is a recommendation from the SHI financial strategy because it gets optimal results so that financial SHI does not occur in a losses. In addition, the results of this study can contribute to the resolution of BPJS Health financial problems in Indonesia which continue to experience a losses.
An Empirical Study of Vehicle Routing Problem for Medical Consumable Materials by Using Clustering Approach: Taking Zueling Pharma Corporate as an Example
Authors: Ouyang W-H , Lin T-Y , Chiou C-C
Published: September 2019

The purpose of the paper is aiming to improve the medical supply distribution routing. From the empirical data, we examine four major issues which are multiple replenishments, unidentifiable distribution spot, implementation of wrong information in the system, and matching issues. Repetition, delay, and cross-district sequence of delivery cause extra transportation cost. We proposed a clustering approach to improve the efficiency. We group all the points into several clusters, then routing the path. A distribution centre inside the hive-shaped formation can significantly shorten the distance and reduce the time by allocating to the surrounding individual point separately. Lastly, the objective of logistics is to satisfy the requirements of the end consumers with high quality service, as a special and integrated activity, logistics plays a focal position in modern society, routing optimization is the main focus of VRP. The most significant improvement is the distribution distance reduced from 52 km to 29.4 km, 43.46%. The cost improvement in terms of time decreased from 130 minutes to 61 minutes, 53.08%.
User Centered Design: Design and Development Methodology of Seed Planting Tools
Authors: Purnomo H , Achmadi O , Hasan I , Mardijanto M
Published: September 2019

Gejlek or Galah is a conventional wood-made seed planting tools aid common used by corn farmers. The limited functions and heavy weight of the existing seed planting caused low productivity and long duration in planting activity. The aim of the research is to design and to develop seed planting tools which able to accommodate user needs. User-Centered Design (UCD) methods used to design product focused on customer satisfaction. 15 respondents involved in this research to measure productivity, practicality, reliability and ergonomic. Validity test represent by F-value produce result test in between 0.354 to 0.625 where Ftest > Ftab means reject H0 or seed planting tools design able to fulfil user needs and different from previous design. User test show how work load against pulse measurement improve 26.44% and Nordic Body Map decrease by average 25% which mean there are significant improvement in terms of work load and ergonomics. It helps increase work productivity.
Priority Proposal in Selecting Fresh Fruit Bunch Suppliers Using Analytical Hierarchy Process (AHP) and Weighted Scoring Model
Authors: Alfaris M F , Qurtubi
Published: September 2019

This article discusses the proposed priority in selecting suppliers of fresh fruit bunches in a company engaged in agribusiness that produces crude palm oil (CPO). The problem faced by the company is that the FFB Internal plantation has not been able to supply all the needs of the fresh fruit bunch. In addition, the supply of fresh fruit bunches from farmer groups is not sufficient for processing capacity. In order to overcome this problem the company must determine potential suppliers to meet the processing capacity of the plant. To determine potential suppliers is done by selecting suppliers based on the appropriate criteria. In determining suppliers, the analytical hierarchy process (AHP) and weighted scoring models are used. The AHP method is used to determine the weighting of the quality criteria for fresh fruit bunches, then the weighted scoring model is used to rank suppliers based on the results of the questionnaire provided. Based on the results of the AHP calculation, the criteria for the quality of fresh fruit bunches, namely clean loose, have the highest weight of 0.24. Then based on the weighted scoring model, the supplier sequence is B (83), C (83), D (83), H (83), E (83) G (81.5), J (80.5), L (80.5), F (80), E (79), I (78.5), K (78), and A (71.5).
Water Hyacinth (Eceng Gondok) As Fibre Reinforcement Composite for Prosthetics Socket
Authors: Widhata D , Ismail R , Sulardjaka
Published: September 2019

Based on the study of water hyacinth fibres, the results of tensile tests and compressive flexural tests for water hyacinth fibre composites laminated with methyl methacrylate resin as reinforcing materials for the manufacture of trans femoral socket prosthesis, showed there is no significant difference in strength and flexibility between water hyacinth fibres and nylon glass fibre which is more often using in orthopaedics technology.

Objectives: This study aims to engineer water hyacinth fibre as reinforcing materials for fabricating trans femoral sockets and perform the structural testing.

Study Design: Experimental, bench research.

Result: The availability and renewable natural fibres has the potential to reduce hazards for those involved in manufacturing the artificial limb sockets, without reducing and compromising the strength of sockets and benefiting for the users. Wall thickness, fibre direction and fibre-matrix resin lamination played a significant role in socket strength.

Conclusions: From this limited study we conclude that the resin and water hyacinth fibre composite socket has the potential to replace the standard layup. Further mechanical and biocompatibility testing as well as a full economic analysis is required. Thus, the use of composites with water hyacinth fibres has the potential to be further developed as an alternative material for socket prosthesis in Indonesia.
Leadership Style and Capability on the Formulation of Business Strategy in the State-Owned Enterprises in Indonesia
Authors: Arif B , Sule E T
Published: September 2019

The performance of the state-owned enterprises (SOE) in Indonesia seen from the total assets, income, and net income for the period of 2012 to 2016, is still not optimal. Such conditions are related to the formulation of business strategy that are based on capability and leadership style. So this study aims to examine the effect of leadership style and capability on business strategy. This study uses quantitative methods with verification analysis. The unit of analysis is SOEs in Indonesia with the observation unit is the management of the company. Data and information are collected in a cross section / one shoot time horizon. The design of the analysis used to test hypotheses is Partial Least Square (PLS). The results of the study show that leadership style and capability play a role in the formulation of business strategy. Capability has a greater role than leadership style in the formulation of the right business strategy. This results have implications for SOE’s management that the formulation of the right strategy is built by superior capabilities and driven by appropriate leadership styles
Review of Cognitive Ergonomic Measurement Tools
Authors: Fista B , Azis H A , Aprilya T , Saidatul S , Sinaga M K , Pratama J , Syalfinaf F A , Steven  , Amalia S
Published: September 2019

In measurement and evaluation for a cognitive performance carried out on various tasks can use objective and subjective measurement tools. This study aims to review research on measuring instruments and provide its potential to be used in research related to cognitive ergonomics. The method that is used in this study is a review of article literature on studies that are subjective and objective measurement tools. the results of this study indicate that in each study usually does not only use one measuring instrument, to validate measurements, but another measurement tool is also used. And in research usually uses subjective and objective measurement tools for the same task.
Design and Implementation of Microstrip Patch Ultra-wide Band Antenna for Detection of UHF Partial Discharge
Authors: Nawawi Z , Sidik M A B , Jambak M I , Ahmad N , Ahmad M H , Kumar C L G P , Waldi E P , Aulia
Published: September 2019

Partial discharge (PD) is an electrical release or spark that occurs between two conducting electrodes that are not bridging, and it can occur at any points in the insulation system. PDs emit electromagnetic field radiation in the frequency range of 300 MHz to 1.5 GHz. Thus, it is more appropriate to detect and monitor partial discharge using an ultra-wideband antenna which offers more accuracy than the narrowband antenna. This paper proposes the design and implementation of a microstrip patch antenna which has been designed to possess wider detection performance of ultra-high frequency (UHF) PD signal. The PD spectra of the designed UWB antenna and the commercial whip antenna was compared and analyzed. The result shows that the UWB antenna can effectively detect the UHF PD signals that occur between two electrodes. As results, it is implied that PD measurement by using designed UWB antenna is found to suitable to detect the PD signals for online monitoring of high voltage equipment.
Design of poka-yoke system based on fuzzy neural network for rotary-machinery monitoring
Authors: Muharam M , Latif M
Published: September 2019

Early detection of machine failure will improve the performance of the production process. The Poka-Yoke device was developed to monitor the machine. The vibration signal is captured by sensors and inputted in Poka-yoke device for processing. Poka-Yoke device has two components, Fuzzy-Neural Network identification and decision maker. The first component, the time-domain signal is transformed into the frequency domain, magnitude and frequency are treated as Fuzzy membership functions by using the statistical parameters as mechanical harmonic distortion and then are trained by Neural Network. The second component, the decision is in the form of machine condition statements such as normal, alarm, and shutdown. Simulation’s results show that the method can be applied to identify the machine condition in term of bearing faults. Moreover, the Poka-yoke system that developed can be used to monitor machine condition automatically.
Parametric sensitivity analysis of SEL-421 distance relay algorithms used in compensated line
Authors: Rohadi N
Published: September 2019

This paper presents the use of Global Sensitivity Analysis (GSA) methods to analyze the sensitivity level of the performance of the impedance measurement algorithm of SEL-421 distance relay protection when used to perform transmission line protection with compensation circuit. This GSA technique was developed to see the dominance effect of system uncertainty (or factors). Two techniques that might be used for sensitivity analysis using GSA are Quasi-Monte Carlo (QMC) and data sampling with Sobol technique. Experimental is done with DIgSILENT software to do modeling of the power system, simulation, and calculation of impedance and algorithm error. The testing is carried out automatically with the help of the developed algorithm using DPL (DIgSILENT Programming Language). SIMLAB software, in this case, (with Sobol technique) is applied to generate some non-linear factor data and analyze the output of variations in impedance measurement errors.
The real-time condition monitoring system of gapless arrester based on ZigBee protocol and third harmonic leakage current as indicator parameters
Authors: Novizon  , Ulfiah S A , Malek Z A , Syafii  , Riska N , Aulia  , Darwison
Published: September 2019

Monitoring the condition of arrester in service have been presented in the past. Several methods of monitoring the condition of surge arrester were introduced by many researchers. Some and almost all the methods are based on measuring the leakage current. The goal of this study is to design a portable arrester condition monitoring system which is capable of performing arrester health analysis without the need for a voltage source reference — the design based on the previous research which introduces the new method to discriminant the resistive leakage current from total leakage current. The method for diagnosing arrester health is only with the leakage current waveform. The advantage of not needing the voltage reference is that the system can ultimately be used in the field where access a voltage reference about 150 kV is not practical. The design employs a ZigBee wireless protocol as well as a microprocessing based system utilizing an Arduino microcontroller. The ground side current from the arrester is fed through a resistor, which can then be used as a read voltage. The LabVIEW based graphical user interface was prepared to analyze an arrester’s data. The user connects the GUI to the Arduino via ZigBee, samples the waveform from an arrester and then additional data processing is executed. The main part of this processing involves the modified shifted current method on the sampled waveform. Upon conclusion, the user is left with only the resistive component of the arrester leakage current, which is displayed in both the time and frequency domains for analysis.
Condition based monitoring of gapless surge arrester using electrical and thermal parameters
Authors: Novizon  , Malek Z A , Syafii  , Ahmad M H , Aulia  , Ulfiah S A
Published: September 2019

A new method to assess the condition of metal-oxide surge arresters is presented. The thermal image and third harmonic leakage current are used as an indicator. The correlation between the leakage current and temperature of the arrester is processed using a neural network. The temperature profile of arrester, ambient temperature and humidity were as input to the neural network and the peak value of the third harmonic resistive current as a target. Results are presented with the training of neural network close to the target and testing result is 98% successfully.
Harmonic analysis in electrical system at Andalas University Hospital
Authors: Afni N , Nazir R , Waldi E P , Pawawoi A
Published: September 2019

In this paper, harmonic distortion in the electrical system at Andalas University Hospital is analyzed. The Total harmonic distortion (THD) was measured by The Fluke 430-II power analyzer for three days from 27th - 29th June 2018. The data were recorded every ten minutes. The THD of the current was from 3.09 % on Thursday at 08.40 (in phase L3) to 9.35 % on Thursday at 23.00 (in phase L1). The values of the THD show that high values of the THD occur at night from 18.00 to 08.00 at morning. The low values for the harmonic distortion of the installation occur during the day from 08.00 to 18.00 that occur for low active power. The harmonic distortion in the electrical system during the day was quite low. The current harmonic distortion was depending on the type of load. The non-sinusoidal current has harmonic content that interacts with the electrical system will create voltage distortion in the electrical system even if the supply is sinusoidal.
Performance analysis of error control coding and diversity in image transmission on wireless channels
Authors: Baharuddin  , Muharam M , Andre H , Angraini R
Published: September 2019

This paper discusses the performance of using error control coding that combines with diversity techniques in the transmission of images on wireless channels to get reliable communication on noise and fading. The performance of the transmission system is not only determined by the effectiveness of channel usage, but it is also determined by the reliability of the communication system that causes noise and fading. Error control coding used in this research is Reed Solomon (RS) code, while the diversity technique used in this research is Maximum ratio combining. RS code is used to correct errors that occur during wireless transmission, while Use of diversity Maximum Ratio techniques Combining expected can affect the number of errors so that the signal transmitted to the wireless channels becomes more robust against interference caused by transmission channels. By using error control coding and diversity, the quality of image transmission at the receiver is increased.
Performance evaluation of image transmission using diversity selection combining technique
Authors: Baharuddin  , Angraini R
Published: September 2019

This paper discussed a simulation of SPIHT image compression transmission on wireless channels by using RS code and diversity selection combining technique in wavelet domain to get better reconstruction image by minimizing errors that caused by fading and noise. RS Code and Diversity Selection Combining Method were used to combat errors during image transmission on wireless channels. When the bit stream data arrived at the receiver, the coding was used to recover the errors in the bitstream. Diversity was used to obtain multiple data streams corresponding to the transmitted image at the receiver. These individual image data streams were combined to form a composite image with the better quality. The results show both methods demonstrated quality improvement of the received image.
Characteristics of acoustic signals from lightning using a microphone array observation system
Authors: Hazmi A , Emeraldi P , Hamid M I
Published: September 2019

The acoustic signals of thunder provide information on the lightning channel, such as frequency, power spectra density, and images. In this study, to analyze the frequency variation in acoustic signals of thunder and to reconstruct the 3D lightning channel imaging, the short time Fourier transform (STFT) and differential time of arrival (DTOA) methods were used. The results showed that the frequency for four microphones varied from 4.88 Hz to 175.78 Hz. Furthermore, the range of power spectra density values for the four microphones was between -0.59 dB/Hz and -28.31 dB/Hz. This system can reconstruct 3D lightning channel imaging.
Robot mobile control based on three EMG signals using an artificial neural network
Authors: Rusydi M I , Aryeni I , Joefrinaldo  , Romadhon Z , Rusydi A
Published: September 2019

The EMG signals can be produced from the human muscle activity. This paper explains the control system of the robot mobile which uses the EMG signal from three muscles contraction such as the jaw muscles, the right arm muscles, and the left arm muscles. The peak values of the EMG signal was used as the input to the ANN system using the Backpropagation algorithm, and it produces the output which has nine target conditions; the forward, then turn right and then turn left where each of them has the variations such as the slow, the medium and the fast. The ANN has been trained with 270 of the training data, and it has been tested with 135 of the testing data from 15 respondents who performed muscle contraction activities. Based on the test result, there are only two unrecognizable data with the rate of the system accuracy is 98.52%. The movements of the robot mobile can be controlled based on the recognized movement patterns with the specified target conditions.
Development of rogowski coil sensor for partial discharge detection
Authors: Waldi E P , Frenzi A Y , Fernandez R , Darmawan  , Darwison  , Laksono H D , Aulia  , Hazmi A , Andre A , Abral H , Arief S , Nawawi Z , Ahmad M H , Hozumi N
Published: September 2019

This paper presents the development of Rogowski coil to detect the partial discharge. Rogowski coil sensor is composed of a ferrite core with a various number of turns which is 5, 10, 20 and 30 turns with a half circle and full circle configuration. The sensors need to be tested based on the number of the turns they have in reading the partial discharge signals. The sensor is connected to a digital measurement device such as a digital oscilloscope which has an input impedance of 50 ohms and 1 Mohm with a time frame duration greater than or equal to 20 ms. The reading comparison is not only between the proposed sensors but also with a commercial partial discharge sensor. The partial discharge signal is generated by a commercial charge calibrator. The measurement result shows that using low impedance lead to decreased noise but the reading is too small compared with using high impedance.
Formulation of optimization model of raw material composition to achieve clinker quality standards (Case study PT Semen Padang Plant IV)
Authors: Rijal S , Indrapriyatna A S , Adi A H B
Published: September 2019

Cement making process required four main raw materials, Lime Stone as a source of CaCO3, Silica Stone as a source of SiO2, Clay as a source of Al2O3 and Iron Sand as a source of Fe2O3. Proportion of raw materials approximately 80% CaCO3, 15% SiO2, 3% Al2O3 and the remaining 2% for Fe2O3. Due to operational constraints in the mine area, Indarung IV plant is experiencing a shortage of SiO2 source material that is Silica Stone, to anticipate this condition selected Pozzolan as alternative raw material because the SiO2 content in Pozzolan is above 60%. This research uses Linear Programming to get formulation model of optimization of raw material composition with Pozzolan as a substitute of Silica stone by minimizing cost. Ash composition factors and calories of fuel are not made into consideration. The results of this study obtained the most optimal raw material composition with minimal cost and meet the standard strength three days clinker min. 200 kg/cm2, by inputting the oxide composition of each raw material and the minimum and maximum constraint into the model formulation. The use of Pozzolan as a substitute raw material for Silica increases raw material costs 265.74 rp/ton.
Analysis of the application of quality management systems in the rubber industry based on ISO 9001:2015
Authors: Fajrah N , Putri N T , Amrina E
Published: September 2019

Increasing competition in the global market and high consumer expectations for quality products, encourage companies to produce quality products of international standards. The rubber industry is part of an industry group that is prioritized in its development in Indonesia. Based on these conditions, companies are always required to develop quality management systems that exist in the production process. The purpose of this study is to analyze the application of the quality management system of the crumb rubber industry to the ISO 9001: 2015 certification standard. The analysis was carried out on case studies and discussions with leaders of crumb rubber companies in Padang City. The success of the implementation is affected by indicators that influencing in ISO 9001: 2015 certification standards. Based on the results of the case study it can be seen that PT B has implemented an integrated quality management system in the company’s business processes. On the other hand, PT A still needs much improvement in implementing an integrated quality management system and integrated with the company’s business processes. It can be concluded that a strong top management commitment is not supported by the application of a quality management system. The implementation of a quality management system has not been optimally demonstrated by the company’s quality control documentation system is still incomplete and the company has not involved all aspects of the company in the implementation of quality management systems.
A framework to improve equipment effectiveness of manufacturing process - a case study of pressing station of crude palm oil production, Indonesia
Authors: Susilawati A , Tasri A , Arief D
Published: September 2019

Overall Equipment Effectiveness (OEE) has been widely used to measure the performance of the production process. A well-performing company is a company that has a high OEE score. Increased the OEE score can be done by minimizing six big losses that greatly affect the score of OEE. In this paper, a framework to determine the actions needed to minimize the six big losses is recommended. The framework was then used to determine the action to minimize the six big losses in palm oil mills. A total of 7 actions were required. The highest ranked action, the most important action, was the improvement of raw material quality while the lowest ranked action was to increase the number of workers.
Effect of pipe diameter changes on the properties of fluid in closed channels using Osborne Reynold Apparatus
Authors: Nur A , Afrianita R , Ramli R D T F
Published: September 2019

The flow profile in the channel will affect the velocity of fluid distribution. One factor that influences the flow profile in a closed channel is its diameter. Therefore, this study aims to analyze the effect of changes in pipe diameter on the nature of fluid flow in closed channels using Osborne Reynold Apparatus. This tool uses a vertical glass pipe with a diameter of 1 cm and 3 cm. The operation of the Osborne Reynolds Apparatus is carried out by flowing the fluid through a channel with a PVC type pipe pumped with a Submersible pump into an acrylic tub, then passing a vertical clear glass pipe. The Reynolds value obtained from each test equipment is 1,323-5,748 with friction factor 0,03-0,04 on Osborne Reynold Apparatus 3 cm diameter and 1,103-4,512 with friction factor value 0,03-0,05 at Osborne Reynold Apparatus 1 cm diameter. It is known that the greater the channel diameter, the greater the Reynolds value will be, while the friction factor will be smaller. Regression and correlation analysis are carried out with the aim to determine the relationship the values obtained and it is obtained that there is a very strong relationship among time, discharge, flow velocity, Reynolds number and friction factor in each test equipment. It is evidenced with the coefficient of determination and the correlation coefficient obtained (R2 = 0.994-1,000 and r = 0.981-1,000).
Synthesis and characterization of calcium precursor for hydroxyapatite synthesis from blood clam shell (Anadara antiquata) using planetary ball mill process
Authors: Gunawarman  , Affi J , Yetri Y , Ilhamdi  , Juliadmi D , Nuswantoro N F , Fajri H , Ahli A , Gundini R , Nur Hadi
Published: September 2019

Calcium precursor for synthesizing of hydroxyapatite can be obtained from natural material like A. antiquata (blood clamshell). Calcium synthesis was carried out through ball mill and calcinations process with high purity residues. Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) were used for characterization. Analysis for blood clam shell powders revealed a reduction of average size from 217μm to 76μm and size of powder crystal is 29,2nm. This powders contained calcium element about 49,67% as the effectiveness of calcination and ball mill process. In morphology, powders have fine needles-like shape but still in agglomerate that can be reduced with extended ball mill process. This powders had a reduction of weight powders from 35,5% to 17,7% and dominated Ca(OH)2 that could be used as calcium precursor in synthesishydroxyapatite.
Production of pig iron nugget from low-grade iron ore and pyrolyzed oil-palm-empty-fruit-bunch composites
Authors: Setiawan A , Suratha R P , Harjanto S , Kusrini E
Published: September 2019

Utilization of low-grade iron ore and pyrolyzed oil palm empty fruit bunch (EFB) is an effective way as the solution to deal with the depletion of iron reserves and administer of empty fruit bunch waste. This study was aimed to analyze the pig iron that is produced by carbothermic reduction of low-grade iron ore with pyrolyzed palm oil EFB as a reductant. The ore from Lampung was reduced at temperature 1400°C and 1450°C for holding time 40 minutes with inert condition (N2 atmosphere). The structures of pig iron were studied by using X-Ray diffraction (XRD), and the microstructures and chemical composition were analyzed by using Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS). It was found that iron nugget that was reduced at 1450°C for 40 minutes that was wholly separated from its slag, with reduction degree 98.5%, metallization degree 99.2%. The microstructure has metallic iron as a base with some pores. On the other hand, the other iron nuggets that are not separated from its slag consist of two prominent phases, metallic iron and lamellar fayalite (Fe2SiO4).
Experimental evaluation of tuned liquid column damper and tuned mass damper in a space structure model
Authors: Son L , Bur M , Andria A D
Published: September 2019

Vibrations in building structure due to external force can be minimalized by absorber installation. One technique in that regard is through the dynamic absorber. Previous reports have developed double dynamic vibration absorber namely Tuned Liquid Column Damper (TLCD) and spring-mass system. However, the conduct has been applied to reduce vibrations occurred on solely one-sided movement. This study investigated the double dynamics absorber utilization of Tuned Liquid Column Damper (TLCD) and spring-mass system that was designed to be capable of vibration reduction caused by interfering forces on two-sided structures hence the implementation can be more applicative.
Atmospheric corrosion map of structural steel in industrial area: a preliminary investigation
Authors: Huzni S , Affandi  , Tanjung I , Fonna S
Published: September 2019

This paper explains the results of the initial stage of investigation of atmospheric corrosion on structural steel in industrial zones. Investigation is carried out on two shape profile of low carbon steel that is widely used for the construction of structures, namely sheet, and elbow. Corrosion rate measurement process and preparation were carried out based on ASTM G-50 and ASTM G-1 standards, with a total exposure time of six months in Medan Deli District, Medan, North Sumatra. The results of this initial stage of the investigation show that the average corrosion rate of low carbon steel for each profile is different, but overall it is still in the “good” category. This investigation will be continued for up to twelve months to obtain more complete data.
Design of solid desiccant air conditioning system
Authors: Saputra D A , Saputra N A , Susanti L , Fithri P , Putra D I
Published: September 2019

Currently, solid desiccant air conditioning system (SDACS) is an alternative to utilize solar energy to resolve environmental and energy issues resulting from the use of conventional vapor compression of air conditioning systems. SDACS can maintain the thermal comfort of a room with optimization of solar thermal energy and minimal use of electrical power. Present work in this paper is to design a solid desiccant air conditioning system of a closed room with 18 m3 of total volume. The desiccant wheel is used to dehumidify air in the room, and evaporative cooling will be decreasing the temperature of the air. The result shows the lower temperature can be reached 24°C.
Numerical analysis of U-shaped hysterisis steel damper with energy absorber for seismic areas
Authors: Satria E , Son L , Bur M , Akbar M D , Haris S
Published: September 2019

This paper investigates one type of metallic dampers used in many large buildings in seismic areas. The previous studies have shown a possibility of the introduced damper to act as a damper as well as energy absorber through yielding on some parts of the damper. However, the occurred yielding caused a plastic deformation after unloading. The study aims to substitute the previous critical area to another part which is considerably uncritical during loading. Therefore, an additional part in the form of a slender column is inserted into the damper. The bottom part of the column is clamped to the base plate of the damper. There is a restoring moment acting on the column which was able to restore a large displacement of the damper to at least a small residual plastic displacement after unloading. A stiffness, strength and energy dissipation of the modified damper is determined by a nonlinear finite element technique which involves both geometrically and materially nonlinearities. The model was subjected by a monotonic increasing load which is applied horizontally through the method of displacement control until one cycle of hysteresis is formed. The final result is in a term of comparison of hysteresis curves between a full model of hysteresis damper with and without a slender column.
Characterization on particle size distribution of reduced lateritic nickel ore using biomass carbon reduction
Authors: Abidin F , Harjanto S , Kawigraha A , Permatasari N V
Published: September 2019

The use of biomass carbon as a reducing agent in lateritic nickel ore reduction is one alternative to substitute dependence on conventional reducing agents such as coal and cokes. The difference in particle size distribution from reduced ore shows differences in characteristics that can be used as a reference in the next step extraction process of lateritic nickel ore. In this study, characterization of lateritic nickel ore reduction at high temperatures using coconut shell charcoal as a biomass carbon reducing agent. Reduction process was carried out at 1200°C and holding for 90 minutes, heating continued until 1500°C and held for 15 minutes. Effect of particle size distribution from lateritic ores reduction was investigated by chemical composition, especially changes in the composition of iron and nickel. Also, mineralogy analysis and microstructure characterization were performed to analyze compounds, morphology and elemental mapping analysis after reduction in each particle size distribution.
The experimental performance of the semi-cylindrical type of solar concentrator collector on the addition of heat storage material
Authors: Harun D , Zulfadhli  , Akhyar
Published: September 2019

The heat absorbability and the efficiency of water heaters are increased by adding phase change material as heat storage in solar water heaters known as cylindrical through collectors type. It used to absorb heat from solar energy and will concentrate towards an absorber pipe containing water, so it can increase the water temperature that flows through the tube. In this study, two absorber copper pipes used with Ø 2.54 and Ø 1.91 cm, respectively. The copper pipes arranged parallel and placed the heat storage materials with different conditions. A drum with a diameter of 55.5 cm and a length of 10 cm is split vertically into two parts which will be used as a cylindrical type of solar collector — the solar intensity measured during the experiment. Results show the highest water out temperature is 65 °C at 13:00 WIB that the position of paraffin inside pipe 2 with a solar intensity is 1195 W/m2 and the efficiency is 13.5%. The water inside of pipe 2 found the water out temperature is 62 °C and the efficiency is 12.31%. The position of air inside of pipe 2 recorded the water out temperature is 60 °C, and the efficiency is 10.21%. It can be concluded that the effect of adding paraffin inside of pipe 2 is better than water and air.
The effect of particle compositions on the activation energy of the pa6/bagasse composite
Authors: Thalib S , Huzni S , Fonna S , Azhari C H , Zakaria S
Published: September 2019

The Activation energy of PA6/Bagasse particles blends was evaluated as a function of particle compositions. The composite was prepared in compositions of weight %PA 6%/weight Bagasse particles, that is 95/5, 90/10 and 87.5/12.5 respectively using a twin screw extruder at 40 rpm and 220 °C blending temperature. The Activation energy is determined based on rheological testing with using a capillary rheometer on constant heating method. In this test, it is obtained the relationship of viscosity and temperature of melting composite. Arrhenius linear plot between viscosity to 1/T. can be obtained the activation energy.
Hardness and impact energy absorbed produced by Q&T steel and DQ&T teel
Authors: Yurianto  , Pratikto  , Rudy S , Wahyono S , Eflita Y , Agus S , Yusuf U
Published: September 2019

Hot rolled plate steel is heat treatable steel made in Indonesia for commercially developed to Quenched and Tempered Steel. This steels made by PT. Krakatau Steel (Persero) Cilegon, Banten, Indonesia. The aim of this study to improve the hardness and energy impact through heat treatment of double quench + temper. The method used is heating up to 900°C (maintained for 30 minutes and cooled by water) for fives specimen hot rolled plate steel and produce the quenched 900 steel (Q900 Steel). Four Q900 steel specimens were heated at 750°C, 800°C, 850°C, and 900°C (maintained for 30 minutes) each. Then five specimens (include Q900 Steel) are tempered at 150°C (maintained for 30 minutes) and produced Q900 & T Steel, Q900+750 & T Steel, Q900+800 & T Steel, Q900+850 & T Steel, Q900+900 & T Steel. Results of the study were changes in microstructure, hardness and impact energy. Hardness and impact energy absorbed of Q900+750&T Steel higher than Q900 &T Steel.