bluuebunny/crossref_metadata_2025 huggingface dataset:
Revisiting Supply Chain System with Deteriorating Items and Transportation Cost
Authors: Huang C V , Huang Y D , Wee H M
Published: September 2019

Supply chain system with deteriorating items and transportation cost with environmental consideration has recently become a popular research stream. This study revisits a supply chain system with deteriorating items and transportation cost. Processing the defective items, which increases cost, affects supply chain decisions. We present an integrated inventory model involving a three-stage supply chain and defective items with no shortage. We then derive the minimal total cost considering supply chain integration and deteriorating items. Numerical examples are provided to illustrate how these models can be applied in practice. Sensitivity analysis is performed to gain more insight on changing parameters in the numerical studies.
A Simple Butterfly Lifecycle Algorithm for Measuring Company’s Growth Performance
Authors: Utama D N , Mitchell A , Fieri B , Richard H
Published: September 2019

Five states of butterfly metamorphoses in its lifecycle naturally inspire algorithm creation. A simple butterfly lifecycle algorithm (BLCA) was successfully created by imitating a real butterfly lifecycle in five stages study; preliminary analysis, literature review, input-process-output analysis, logic analysis, and algorithm construction. The algorithm was represented thru activity diagram, pseudo-code, and class diagram. The dummy case of measuring company growth performance used to experimentally test the algorithm.
Assessing The Efficiency of Small and Medium Industry: An Application of Data Envelopment Analysis
Authors: Pramono S N W , Ulkhaq M M , Pujotomo D , Ardhini M A
Published: September 2019

The educational toy business is one of the businesses with a good prospect and is expected to continuously grow. The estimated spending of educational toys in Central Java is 757,257 units per year. However, the local manufacturers can only fulfil 27% of the total needs, while the rest are filled by other manufacturers from Daerah Istimewa Yogyakarta or even from China. This is due to the high selling price, so it is less competitive compared to other competitors—according to the Chairman of “Asosiasi Penggiat Mainan Edukatif dan Tradisional Indonesia”. This high selling price is affected by high manufacturing cost caused by waste in resources usage; or in other words, low efficiency. This paper aims to investigate the relative efficiency of manufacturers’ education toys by employing the data envelopment analysis approach. Results show that three manufacturers are categorized as inefficient. Recommendations would be given so that the manufacturers could improve their efficiencies.
Integrating House of Risk Method with PESTLE and CIMOSA for Risk Assessment of Java-Bali I Power Plant Construction Project
Authors: Muntoha A , Sudiarno A
Published: September 2019

Java-Bali I Combined Cycle Power Plant Project is part of 35,000 MW electrical generating development program. To fulfil the project construction objectives, a risk assessment is needed. It is started with risk identification using PESTLE analysis and CIMOSA approach. It can be identified that there are 18 risk events for external factor, 22 risk events for internal factor and 54 risk agents that will be analysed using House of Risk (HOR) stage 1 method. Focus Group Discussion (FGD) is held for assessing severity of each risk events and occurrence of risk agents, also the correlation between them. Using HOR stage 1 is obtained Aggregate Risk Potential (ARP) value for each risk agents. Using pareto analysis, 11 risk agents is chosen as priority and will be evaluated using HOR stage 2. Using HOR stage 2 method, 7 preventive actions (PA) are identified to prevent risk agents occur. As final result, using Cost Benefit Analysis (CBA), 7 recommendations is suggested in order to make project successful according to the target specified.
Determining The Importance Factors of Financial Technology Adoption in Hospital Using Fuzzy Analytical Network Process (FANP)
Authors: Dachyar M. , Ilahiyyah E N , Farizal
Published: September 2019

Electronic money transactions in Indonesia have grown rapidly with an average 66% from 2012 to 2018. Unfortunately, according to Jakpat Survey in 2018 said that until 2018, there’s still no adoption of financial technology in health services. This paper aimed to determine the important factors of financial technology adoption by hospital clustering with Fuzzy Analytical Network Process (FANP) method. This paper used the questionnaire from 35 hospital experts as the respondents from all around Indonesia. Scope data in this paper came from outpatient unit administration payment in Hospital. Fuzzy Analytical Network Process (ANP) were used to find the most significant factor from Technology, Organization, Environment, Human (TOEH) framework. This paper found that the most important factor and sub-factor for the hospitals in cluster 1 were technology and compatibility. Meanwhile, for the hospitals in the cluster 2, the most important factor was environment and the most important sub-factor was government pressure.
The Prediction of Logistic Needs of Emergency Response for Victims of Merapi Volcano Eruption in Regency Sleman, Yogyakarta
Authors: Handayani N U , Rinawati D I , Sari D P , Rifa’i P M
Published: September 2019

This research aims to predict the logistic needs for natural disaster victims of Merapi Volcano in Regency Sleman. Merapi volcano is chosen as the object of the research since it has been the most active volcano in Indonesia. The effort to maintain the logistic in times of emergency response by the authority has still been in responsive mode. It causes its ineffectiveness in maintaining the logistic for disaster. Frequently, there have been oversupply for a certain item, however, other items could not meet the demand. This research view in detail the needs of the victim based on the category of age and gender where there are 6 categories namely age of 0-2 years old, male aged 3-5 years old, female aged 3-5 years old, male aged 6-59 years old, female aged 6-59 years old and elderly aged >60 years old. The prediction is done in each refugee camp established in Regency Sleman. The result of the prediction logistic support for victims of Merapi eruption could become a facility of information for the government as well as for the community within the affected area so that the handling of logistic support for disaster at the time of emergency response could be maintained effectively and efficiently.
Strategy for minimizing risk of electronic waste management using the Analytical Hierarchy Process (AHP)
Authors: Rimantho D , Noor E , Eriyatno  , Effendi H
Published: September 2019

Electronic waste management is one problem that has the potential to pose a risk to the environment and human health. The strategy to minimize the impact level on e-waste management has been extensively carried out in almost all countries. This paper aims to analyse strategies for minimizing the risk of e-waste management. The AHP method was used in this study. The assessment used a paired comparison questionnaire by five experts such as academics, governments and NGO. Studies show the first priority strategy is improving regulation and monitoring with a weight around 0.493. In addition, the sub-criteria chosen by experts are legal compliance with a weight of approximately 0.629 and the criteria that are the top priority are regulations with a weight of around 0.525. The assessment by experts also shows the value of the consistency ratio of around 0.07. This research can be a strategy by policy makers to manage sustainable e-waste. It is considered necessary to conduct further research related to other criteria and sub-criteria that may be different in the management of e-waste in other regions.
Manufacturing Efficiency Improvement Through Lean Manufacturing Approach: A Case Study in A Steel Processing Industry
Authors: Indrawati S , Azzam A , Ramdani A C
Published: September 2019

The idle and delay time in an industry is categorized as production waste that will cause problems such as production quantity below the target. In addition, the waste also leads to cost losses and eliminate opportunities for the industry to gain profit. The need of waste analysis to optimize the costs incurred due to the idle and delay time. Lean manufacturing approach can be used to minimize that production waste. Value stream mapping (VSM) is one of lean tools that can be used to identify all production activity for an industry. This study is conducted in a steel processing industry. The result shows that the dominant production waste is delay time. There are seven factors causing the main production waste, i.e. operation, mechanic, adjustment, electric, computer, instrument, and utility. These factors are the cause of production waste and production activities that do not add value to product. A maintenance improvement program is developed to reduce the production waste. Manufacturing cycle efficiency in actual condition is 68,08% while efficiency value in the future condition is 71,3% so from proposed improvement plan that can increase manufacturing cycle efficiency equal to 3,75%.
Product Segmentation of Wooden Handicraft Micro, Small and Medium Enterprises (MSMEs) in Indonesia
Authors: Christine M G F , Dachyar M , Nurcahyo R
Published: September 2019

The intense competition between wooden handicraft Micro, Small and Medium Enterprises (MSMEs) in Indonesia has encouraged business owners to generate creative innovation in order to maintain the sustainability of the company. This study aims to develop the new product development strategy based on the product segment characteristics from wooden handicraft MSMEs in the Special Region of Yogyakarta, Indonesia. The segmentation of products was done by applying the combination of K-Means Algorithm and Frequency, Monetary, Customer Variety (FMC) variables to the customer transaction data. The results showed five different types of product sales characteristics in three wooden handicraft MSMEs. It will encourage business owners to gain valuable insights about useful product sales characteristics for building business strategies to face increasingly fierce competition in this era.
Supplier Selection Model Based on Risk in an Indonesian Healthcare Service Industry
Authors: Indrawati S , ‘Azzam A , Cahaya H I
Published: September 2019

In Indonesia, healthcare services are a priority industry sector. In the last few periods, every health care provider began to evaluate and make a performance improvement of the entire supply chain. Supplier selection is one of supply chain business process that have some risks. Therefore, this research is conducted to identify and reduce various risks in supplier selection process. The method used is Fuzzy Failure Mode and Effect Analysis (FFMEA) with three main stages, i.e. fuzification, rule evaluation and difuzification. The result show that there are four criteria, i.e. price, communication, quality and delivery time used for supplier selection in an Indonesian healthcare industry. Each criterion has some supplier performance risks with a total of 10 failure modes. The integration of risk factors in supplier selection model have been successfully done with one best suppliers based on the lowest risk score.
Comprehensive Framework of E-commerce Adoption in Indonesian SMEs
Authors: Hayati I , Andrawina L
Published: September 2019

The use of Internet has been growing rapidly in the last decade. One of the popular uses of Internet is e-commerce which gives changes in the market and forces companies to adapt to survive, including small-medium enterprises (SMEs). As one of developing country, e-commerce adoption among Indonesian SMEs is still low with only 8\% of SMEs has adopted e-commerce. Despite many researches regarding e-commerce adoption, the topic still needs a comprehensive study on internal and external factors affecting e-commerce adoption. This study aims to fill these gaps by developing a comprehensive framework on e-commerce adoption among Indonesian SMEs. The originality of this study resides in managerial demography and company’s knowledge management as additional factors to the model proposed by previous studies. This study concludes four external dimensions and five internal dimensions affecting e-commerce adoption. The external dimensions are institutional environment, economic environment, socio-cultural environment and technology environment. While the internal dimensions consist of managerial demography, company’s size, company’s capabilities, corporate strategy and company’s knowledge management.
An Analysis of Variables Affecting the Implementation of Patient Safety in Budi Sehat Hospital Purworejo using Partial Least Square
Authors: Buwono R I , Suhardi B , Pujiyanto E
Published: September 2019

Budi Sehat Hospital Purworejo is a healthcare facility whose status recently changed from general inpatient clinic. During the process of this status change, the hospital faced several obstacles related to patient safety. Near-miss cases include wrong diet for a patient, a near case of injection mix-up, wrong drug administration, wrong drug dose, a prescription error and one adverse event case of phlebitis. This study aims to minimize patient safety incidents by identifying variables that affect the implementation of patient safety in Budi Sehat Hospital Purworejo. Variables used in this study include teamwork climate (X1), safety climate (X2), job satisfaction (X3), stress recognition(X4), perceptions of management(X5), working conditions(X6), motivation (X7), supervision (X8), leadership style(X9), communication (X10), turnover intention(X11) and frequency of patient safety events reported (Y1). The method used in this study was the Partial Least Square (PLS). Results showed that the most influential variable was working conditions (X6) with p-value of 0,01 and R-squared of 0,393.
Analysis of Changing Working Patterns on an Overhaul Activity in a Power Plant Industry using Lean Manufacturing Concept
Authors: Fattah A A , Sudiarno A
Published: September 2019

East Region Maintenance Service Unit (UPHT) has three main targets to implement maintenance activities, namely on quality, on cost, and on time. These three targets are a form of UPHT commitment in maintaining customer confidence on work result. PT PJB (Bali Java Generation) wants UPHT to optimize the duration of overhaul time. The possible strategy could be applied consists of detailing working breakdown structure (WBS), working in two shifts, roll in - roll out spare parts, and the establishment of a competent quality control team. In this research, value added, non-value added, necessary non-value added, and workload activities were analyzed to optimize quality, duration, profit and minimize budget on project management overhaul gas turbine units. The instrument used in this study were Yamazumi Chart and NASA-Task Load Index (NASA-TLX). The results showed the percentage of value added activity was 38%, necessary non-value added was 51% and non-value added was 11% of the total overhaul. There is the potential to shorten the duration of the major overhaul changes in work schedules from those originally scheduled for 32 days, to only 18 days by using the two-shift pattern. The profit earned from shortening the duration of the overhaul is IDR 2,500,975,763.74.
Health State Indicator-Based Vibration Signature for Gearbox Condition Monitoring and Maintenance
Authors: Widodo A , Satrijo Dj , Prahasto T , Haryanto I
Published: September 2019

Gearbox is a device used to transmit the power of rotating machinery from the prime mover to the equipment with or without change in rotational speed. The working condition of gearbox is usually experienced in heavy load, suffering high friction when contacted with pinion and running in high speed rotation. Therefore, the condition of gearbox must be reliable to ensure the functional operation. The present study deals with development of health state indicator derived from vibration signature for gearbox condition monitoring and maintenance. Vibration technique is still the best way to machine condition monitoring including gearbox. However, wear detection of gearbox is still under study due to the difficulties of capturing best signature of wear by means of vibration signal. In this study, health state indicator is proposed based on vibration signature to monitor wear progress in gearbox thru averaged and moving-averaged logarithmic ratio from filtered vibration signal. The results show that averaged logarithmic ratio is increased as well as the increasing of wear based on experimental work. Moving-averaged logarithmic ratio is also investigated in present work and both method has potential to be indicators for wear monitoring and detection.
Productivity Evaluation Through American Productivity Center Approach at PT Sejahtera Furnindo
Authors: Ahmudi  , Mahachandra M , Handayani N U
Published: September 2019

PT Sejahtera Furnindo, a well-established export furniture company in Central Java, currently only considering the profit level to study its performance. With this approach, company usually pays only a little attention to its resources usage efficiency, that makes it requires a large cost to carry out company activities. For finding a more comprehensive approach, this research offers an evaluation of company productivity measurement using American Productivity Approach (APC). Results of this study showed that total factor productivity during the measurement periods indicate a positive growth level. This illustrates its success in managing labor input and collective capital owned. However, the total productivity revealed a changing level of growth, which illustrated that company had not been able to manage the overall input successfully during the measurement periods. Efforts are needed to increase the profitability for the coming period, along with efforts to increase productivity that focus on increasing material productivity and capital productivity as input factors that were also significantly influenced its profitability.
Traffic Accident Severity Prediction Using Naive Bayes Algorithm - A Case Study of Semarang Toll Road
Authors: Budiawan W , Saptadi S , Sriyanto  , Tjioe C , Phommachak T
Published: September 2019

A traffic accident was one of the leading cause of death in Indonesia. Toll Road is one of the places where traffic accidents occur. In 2007-2017 there were 501 accidents at Semarang Toll Road. Accident in Semarang Toll Road has a variety of severity. The most severe case is death. A traffic accident can lead to death. One of the ways to decrease the number of the accident was decreased the severity of the accident. This achieved by making a prediction model. The prediction model can predict the severity of the accident based on the attribute affecting the severity of the accident. In this research, Days, Type of Road, Weather, Condition of Road, Time of the accident, Sex of Driver, and Type of Vehicle were chosen as attributes to make prediction model of accident severity. Naive Bayes algorithm was used to make the model which can predict accident severity. The result was an accident prediction model with an accuracy of 39.49% to predict accident severity and the probability of an accident.
Descriptive Relationship Analysis Between the Program for Pollution Control Evaluation and Rating (PROPER) and ISO 14001
Authors: Nurkhaeriyah F R , Nurcahyo R , Dachyar M
Published: September 2019

In the last decade, the program for pollution control evaluation and rating (PROPER) in environmental management and ISO 14001 has been used by companies to reduce industrial pollution in Indonesia. Both programs are important for companies to handle environmental problems. ISO 14001 certified company will get pressure to develop their environmental performance systems in measuring and evaluating the effectiveness of programs related to environmental management. PROPER may be effective for ISO 14001 certified companies to reduce industrial pollution and be used to measure the company’s environmental performance. This study aims to investigate the relationship between PROPER and ISO 14001 in controlling, managing and monitoring the environment. Descriptive analysis method is used in this study. The results of this study indicate that there is a relationship between ISO 14001 and PROPER, where the implementation of ISO 14001 helps or effectively for companies to get a better PROPER award and PROPER can be used as an environmental performance to measure the effectiveness of ISO 14001.
Location Selection Analysis for New Shipyard Using Integration of DEMATEL and ANP: A Case Study (PT IKI)
Authors: Sukisno  , Singgih M L
Published: September 2019

A shipyard is a manufacturing industry that has a capital-intensive character with very high investment value to build the production facilities, requiring serious planning, handling, and management to survive and grow as a healthy industry. PT IKI headquartered in Makassar is planning to expand its business to one of three alternate areas (Ambon, Sorong, and Timika). Determining the location of the new shipyard from existing alternatives need to be done carefully using advance method due to the complexity of the factors and the interrelationship between factors, by first identifying factors that influence (dispatcher) and are influenced (receiver) in selecting shipyard locations and identifying their respective weights factors, will result in the selection of the most strategic location with comprehensive consideration. The influencing factors (dispatchers) and influenced (receivers) in the selection of shipyard locations were obtained by the DEMATEL method, the weight of each factor was analyzed using the DANP method with the results of raw material costs being a priority factor with scores value 13.73%, then the from AHP method obtained the most strategic alternative location is Ambon as the location of the new shipyard with a score value of 40.94%.
Modified Double Sampling Control Chart for Monitoring The Coefficient of Variation
Authors: Rozi F , Pasaribu U S , Mukhaiyar U , Irianto D
Published: September 2019

Monitoring the coefficient of variation (CV) has received wide attention in quality control, mainly used when the process mean and standard deviation are not constant. This work proposes a modified Double Sampling (DS) chart for monitoring the CV, denoted DS-G chart, in order to improve the sensitivity of previous DS chart for monitoring the CV, denoted DS-γ chart. Some numerical results for statistical properties of the proposed chart and performance comparisons are provided in the form of tables. Based on the average number of observation to signal (ANOS) performance, the proposed DS-G chart outperforms the DS-γ chart.
Critical Success Factors Evaluation of the ISO 50001 Energy Management System Implementation (Case study: PT. APAC INTI CORPORA, Bawen, Semarang Indonesia)
Authors: Purwanggono B , Ferastra K , Bachtiar A
Published: September 2019

Rapid growth makes the industrial sectors contribute as a significant greenhouse gasses producer. According to the Indonesian Ministry of Industry data, the industrial sectors dominate energy consumption with a share of 49.4% of total national energy consumption. These energy needs tend to increase along with economic growth and global population rise. Based on this problem, development of standards related to energy management system is needed for the industrial sector. PT. APAC INTI CORPORA (AIC) is a textile company, located in Bawen, Semarang Indonesia. PT. AIC has implemented ISO 50001 since 2014 as an energy management system to improve the company’s service quality and financial benefit. In this study, Critical Success Factors from the application of ISO 50001 at PT. AIC will be evaluated to assist companies in implementing a more optimal energy management system. A critical success factor is an area in the form of indicators that identify the success of an organization’s performance. Data processing resulted in 8 improvement strategy points based on importance weights (AHP Method) and performance values (Performance Rating) for each subfactor. Through the Delphi method, the improvement strategies is adjusted to the company’s conditions and reduced to 6 strategy points.
Loyalty Improvement of Indonesian Local Brand Fashion Customer Based on Customer Lifetime Value (CLV) Segmentation
Authors: Dachyar M , Esperanca F M , Nurcahyo R
Published: September 2019

There has been a significant growth of internet users over the past decade in Indonesia. The growth of internet users is followed by the growth of digital buyers. Most digital buyers in Indonesia make some transactions to purchase clothing which explains the phenomenon of e-commerce fashion growth. This study aims to identify the loyalty level of an electronic customer based on Customer Lifetime Value (CLV) of the customer segmentation and design the CLV improvement. Customer segmentation performed using the K-means algorithm and RFM analysis. This paper used 3 transaction datasets from 3 different local brand fashion e-commerce in Indonesia. This study found five customer segmentations according to CLV ratings as the best, valuable, potentially valuable, average, and potentially invaluable customer. Maintaining customer convenience while doing the transaction and improving service quality and customer trust are the keys to retaining potentially valuable, average, and potentially invaluable customers
A Simulation-Based Approach to Assess Eco-Process Innovation Performance
Authors: Dahan S M , Yusof S M
Published: September 2019

In the recent decade, eco-process innovation practice has been prioritised over other green strategies to help manufacturing firm becoming more sustainable. This paper evaluates the improvement in production cycle time as an outcome of the eco-process innovation, using the actual data of a manufacturing facility. Discrete event simulation approach was adopted to model and simulate the cycle time of previous state and current state of an eco-innovated production line. Result of cycle time per entity revealed a 6% reduction, thus proving that implementation of eco-process innovation could improve the economic performance of manufacturing firm. The study is a small part of a larger research work of which the authors are developing indicators for measuring eco-process innovation performance at firm level.
Changes in Layout and Handling Method for Raw Materials to Reduce Put Away and Picking Time: A Plastic Packaging Manufacturer Case Study
Authors: Parameswari Z , Pujawan I N
Published: September 2019

This research was conducted at a plastic packaging manufacturer, where the company is required to be able to respond to customer demand from the aspect of raw materials storing process. However, the existing the warehouse is not clear. Improvement plan to reduce the put away and picking time in the raw material warehouse were conducted by changing the layout and handling method. Layout change was designed based on raw material selectivity and consumption rate with two improvement scenarios. Scenario I was designed by ignoring the area for the PET group, while scenario II was designed by determining the area for the PET group. The handling method which was originally using porters was changed to using a forklift. In the put away process, the layout change by determining the area for the PET group could decrease the travel distance of 6.96%, and the handling method change could decrease the travel time of 79.34% and total put away time of 68.84%. In the picking process, layout change by ignoring the area for the PET group could decrease in travel distance of 1.81%, and handling method change could decrease in travel time by 86.92% and total picking time of 65.86%. Based on these results, the handling method change could give better result on the decrease of put away and picking time than the layout change. By implementing this recommendation, the company could save their operational cost by the estimation of 24.03%.
Power loss estimation of polymeric housing surge arrester using leakage current and temperature approach
Authors: Novizon  , Malek Z A , Ahmad M H , Waldi E P , Aulia  , Laksono H D , Riska N
Published: September 2019

The good operation of metal oxide surge arresters depends on the increment of temperature. If the arresters cannot quickly disperse the absorbed energy into the ambient, arresters temperature may exceed its operating temperature limit. Consequently, thermal runaway occurs and results in power loss. In this paper, thermal characteristics and thermal stability based on power loss calculation were investigated. Applied voltages, leakage current, and temperature were the main parameters consideration. The power loss calculated by the electrical model is the input to the thermal model. The electro-thermal model is used to determine the two intersection points (stable operating point and the thermal instability point) of the power input and heat loss curves. The results show that irrespective of the different magnitude voltages applied to the arrester and different energy ratings for the elements, the power loss occurs at the certain applied voltage.
PWM speed control of dc permanent magnet motor using a PIC18F4550 microcontroller
Authors: Fatma M W , Hamid M I
Published: September 2019

The purpose of this design is to study the advantages of controlling the DC motor speed by adjusting the permanent magnet of DC motors. This had been done by applying the PWM method with relay using PIC18F4550 micro-controller. The output signal from each controllers were compared with the control system and describe the output value and data related to the system. The result shows that the PWM method was able to maintain the motor speed better than the continuous voltage method.
Partial discharge characteristics of nanosilica biopolymer under AC voltage
Authors: Aulia  , Waldi E P , Darwison  , Anggaravidya M , Novizon  , Setiawan M H , Nugraha Y , Abdurrahman  , Hafizi M A , Jambak I
Published: September 2019

The dielectric properties of LDPE-NR biopolymeric insulating materials can be improved by adding the silica nanoparticles in a certain percentage of weight into the composite. In the present study, four types of bionanopolymeric samples were prepared. To each sample, the nanosilica particles with a weight percentage of 1.5%, 3%, 4.5% and 6% a were added. To see the electrical characteristics, the four samples were placed under the AC high voltage for 1 hour and the partial discharge (PD) signals were recorded continouesly in that period of time. The results show that the number of positive and negative PD pulses for each silica sample after 60 minutes of testing was not the same for all samples. The that samples with a higher percentage of nano silica had fewer PD pulses. This indicates that nanosilica particles can improve the PD resistance of LDPE-NR insulation materials.
Analysis of the unbalanced harmonic propagation in a three-phase power system using a parallel program
Authors: Yunus S , Dinata U G S , Nazir R , Aulia
Published: September 2019

Operation of non-linear in an unbalance condition can cause harmonic problems in the power system. There are two parts in the use of computing time in harmonic load flow, the first in the construction of harmonic admittance matrix and the second is the iteration scheme for solving systems of linear equations. The solution technique of the harmonic admittance was developed as a parallel application, and a direct algorithm to calculate the admittance matrix elements. The three-phase power flow program is devided into three independent subproblems, namely: positive, negative, and zero sequence network. Positive sequence network had been been solved by using the Newton Raphson method without modifying their formulation. Negative and zero sequence networks had been solved using nodal voltage equation. All three sequence networks have been modeled by three independent circuits and solved simultaneously using multi-core processors in parallel programming. The results showed that the parallel three-phase load flow speed is higher than the sequential.
Morphological characteristics of preliminary breakdown pulses of hybrid intra cloud–negative cloud-to-ground lightning at low lattitude
Authors: Emeraldi P , Hamid M I , Hazmi A
Published: September 2019

Preliminary breakdown (PB) pulses can represent the propagation path of lightning initiation and can be used to model the charge structure of a thundercloud. The characteristics of PB pulses from the lightning initiation process depend on the charge structure of the lightning cloud. This study presents the PB pulse morphology and charge structure of thunderclouds from hybrid intracloud–negative cloud-to-ground (hybrid IC-NCG) lightning in Padang, Indonesia. PB pulses were obtained from lightning radiation electric field observation. A total of 41 PB pulse waveforms of hybrid IC-NGC flashes were analyzed. Three types of PB pulse characteristics occurred in association with three different types of hybrid IC-NCG lightning morphologies. Hybrid IC-NCG lightning can be initiated from the main negative cloud charge to the upper positive cloud charge or vice-versa. The propagation direction of the initial PB pulse train of hybrid IC-NCG flashes is either upward or downward.
Increasing the quality and power capacity of HERIC PV-Inverter through multilevel topology implementation
Authors: Hamid M I , Ardiansyah D
Published: September 2019

In photovoltaic generation applications, high efficiency and good output power quality inverter are very important. The most common way to improve the quality of the inverter output voltage is to increase the switching frequency. However, at the same time, this method will increase power losses. This paper introduces a new topology inverter: HERIC multilevel, as an inverter that has good voltage quality (low THD) with a low switching frequency. This topology was tested and analyzed by performing simulations to compare it with the conventional HERIC and cascaded H-Bridge inverters. The results prove that the multilevel HERIC inverter has a lower THD compared to the two inverters. At the switching frequency of 2500Hz; Multilevel HERIC inverters have THD, 1.23%, cascaded H-bridge has 1.34% THD, and conventional HERIC THD 11.4%.
Partial discharge signal denoising by using hard threshold and soft threshold methods and wavelet transformation
Authors: Zaeni A , Kasnalestari T , Khayam U
Published: September 2019

The important thing to do after we detect the existence of partial discharges inside an isolation system is signal processing. One form of signal processing that needs to be carried out on the generated waveform is denoising or noise removal from the wave obtained. In this study, an experiment will be conducted to denounce partial discharge waves using Wavelet and Threshold transformations. Wavelet transformation is applied in various levels then we compare the best denomination while denoisation using Threshold is applied using Soft Threshold and Hard Threshold.
Preliminary results on the development of monoester type insulating oil from coconut oil
Authors: Rajab A , Putra F E , Ramadhani J S , Silitonga M S I , Kurniawan R , Qibran K , Latif M , Hamid M I
Published: September 2019

Vegetable oils, both in tri-ester and monoester forms have been attractive alternative substitutes for replacing mineral oil as the insulating liquid used in power transformer. An effort to develop a monoester type insulating oil derived from coconut oil has been conducted, and the preliminary results of the development are reported in this paper. Five different samples were prepared from methyl ester of coconut oil based on their melting point. The important properties of oil samples such as viscosity, water content, acidity, and density were tested, and are evaluated based on the standard specification of natural ester used for the transformer. Another fundamental property, i.e., oxidation stability was also tested and is evaluated by comparing the corresponding result of mineral oil. It is found that oil needs further treatment before being able to be used as insulating oil.
A system for improving suppliers evaluation: the case of procurement in educational institution (Case study: Andalas University)
Authors: Farid M , Hadiguna R A , Kamil I
Published: September 2019

Supplier selection is one of the problems in both profit and non-profit organizations that need to be resolved efficiently. One of non-profit organizations is a college. Colleges aim to produce quality graduates. One factor influencing the quality of graduates is the availability of facilities and infrastructure to support the learning process. To obtain good quality facilities and infrastructure, a procurement process is needed by involving the supplier selection process. One way to get a good supplier is to use a Decision Support System (DSS) to help the supplier selection process efficiently. The design is done by integrating databases, mathematical models and information models that are packaged in a user interface (UI). Database design consists of a database of criteria, assessments, inventory data and supplier work lists. Design a mathematical model combines a Likert scale for determining criteria with the TOPSIS method for supplier ranking and Knowledge Management as additional support for supplier assessment. The results obtained are not only fixated on the supplier sorting process, but also display information on supplier data, job list and management of inventory items as supporting decision making and increase the effectiveness and efficiency of supplier selection processes into real time.
An evaluation on Dr. M. Djamil Hospital Padang parking lot capacity
Authors: Alfadhlani  , Yasrin W S F , Afrinaldi F
Published: September 2019

Parking is an element that cannot be separated from a facility, including hospitals. Dr. M. Djamil General Hospital, one of the health facilities located in Padang, should have an adequate parking space according to the standard designed for parking facilities. This research is conducted to evaluate the condition of the hospital parking facilities, started by calculating the existing capacity of the parking facility for motorcycles and cars. The next step is estimating the demand for parking spaces based on a one-week observation. Finally, the capacity is compared to the demand for parking areas. It was found 319 and 551 parking spaces available for cars and motorcycles. While based on the observation, it is also known that the maximum demands are 453 and 1038 spaces for cars and motorcycles, respectively. Furthermore, the current parking layout condition has not met the standard yet. This study proposes two kinds of improvement. First, additional parking lots are required, and it is designed based on the demand-capacity comparison. Second, the management of the hospital is suggested to regulate the number of vehicles that can park in the hospital parking area. The main contribution of this paper is on the parking lot design alternatives provided to the hospital.
Identification criteria and indicators of palm oil industrial solid waste processing technology
Authors: Ishak A , Ali A Y B
Published: September 2019

The palm oil industry continues to grow from year to year — processing of the palm oil industry into Crude Palm Oil (CPO) and Palm Kernel Oil (PKO). The ratio of the amount of oil produced by both products is 30% of the raw material. This means that 70% is palm oil waste. The amount of palm oil waste will increase in line with the development of the palm oil industry. The amount of waste generated by the palm oil industry if it is not handled properly and effectively will contribute significantly to environmental damage. Industrial activities ranging from raw materials to produce products will disrupt the lives of people around the factory. There are many alternative technologies available to process other industries, but problems that often occur are difficult to implement the most appropriate technology. This paper describes an application of multiple criteria analysis (MCA) in assessing criteria and indicators of palm oil industrial solid and liquid waste. These methods were used in a participatory decision-making environment where a team representing various stakeholders and professionals used their expert opinions and judgments in assessing different criteria and indicators (C&I).
Design of ergonomic grated coconut squeezer
Authors: Dewi D C , Novrianti  , Handayani C , Wulandari O , Nurhayati I
Published: September 2019

The use of machines with manual technology is still a mainstay for small industries, especially home industries. One of them is the activity of squeezing grated coconut that still uses hands repeatedly. Users experience musculoskeletal complaints in the hands, body, and neck. The design of grated coconut squeezer has the aim to create a squeezer that provides comfort and does not cause musculoskeletal complaints. This design uses anthropometric theory to produce the product size according to the user. The anthropometric data used in the form of pulse size and standard Nordic Questionnaire (SNQ) filling questionnaire were carried out directly. Data processing was carried out by the sufficiency test, and data uniformity, percentile calculation, fatigue analysis, and statistical tests. The result of this design is an ergonomic grated coconut squeezer. Based on the statistical test Paired Sample t-Test is known the difference in pulse rate before and after using a grated coconut squeezer that illustrates the results of the device being made.
Chili sauce production planning model considering raw material availability: An application of Mixed Integer Linear Programming Method
Authors: Jonrinaldi  , Adi A H B , Novira R
Published: September 2019

PT Bina Usaha Keluarga Sedep Roso is one of agroindustry located in Padang producing chili and soy sauces. Chili and soy sauces main ingredients are sweet potato and black soybean, respectively. Both chili and soy sauces have a broad market in West Sumatera, Indonesia. The problem often faced by companies is that the demand for chili sauce product cannot be fulfilled because of seasonal and perishable factors of the sweet potato. It became scarce and expensive outside the harvest season otherwise the excessive supply and low price in the harvest season. This paper proposes an application of mixed integer linear programming to manage production planning of chili sauce to minimize total operational cost and increase the service level considering raw material availability and production capacity of chili sauce companies. The mixed integer linear programming method is applied because there are some constraints on the problem. The mathematical model is developed to obtain the optimal solution in allocating the available resources with given constraints regarding raw material availability and production capacity. The numerical example is given to illustrate the model and show results. Sensitivity analysis is performed to see the changes in the optimal solution caused by the changes in the input parameters of the model.
Designing of welding jig for productivity improvement and cost-savings in thresher’s cover assembly: A Case Study on CV Citra Dragon Assembly Plant
Authors: Mulyadi I H , Putri N T , Muhammad F
Published: September 2019

Needs for efficient assembly process has led CV Citra Dragon, a medium-scale manufacturing enterprise of agricultural machinery, to utilize welding jig for assembly one part of thresher component as their high demanding product. That component is thresher’s cover that has the potential for productivity improvement hence cost savings. Due to categorize as a specific work-holding device for particular purpose and conditions, design processes of a welding jig has been carried out. This has resulted in the development of a welding jig for assembly of thresher’s cover. The design of welding jig has been evaluated from possibility to deflect during its operation, and it was identified that deflection magnitude of welding jig construction was relatively low. Thus, it can infer that this welding jig can resist operational loads. Furthermore, the productivity and cost-effectiveness analysis were also conducted to ensure the welding jig having fulfilled the objective of the proposal. The analysis indicated that the assembly process becomes efficient as a welding jig deployed. It was contributed by shortening of assembly cycle times that increase the production rate. Also, affordable cost savings can also be obvious especially for labor cost salary.
Technical characteristics’ determination of crumb rubber product by using quality function deployment (QFD) phase I
Authors: Ginting R , Widodo
Published: September 2019

Products that have the best quality are products that are produced by researching consumer’s need. Product indicators that have the best quality are the linkages between technical characteristics and consumer’s need. PT XYZ is a company engaged in the production of crumb rubber products. However, the products produced are not by the needs of consumers because there are differences between the indicators required and the indicators produced by the company. The purpose of this study is to identify technical characteristics that are by consumer needs. The method that can be used is the Quality Function Deployment (QFD) method. The QFD method is a method that relates the relationship between consumer needs and product characteristics to obtain the products quality. In other words, by using the QFD method, consumer needs can be translated into technical characteristics so that improvements can be made to prioritized technical characteristics. The results obtained from this study are stating that the priority characteristics obtained are the speed of production with a difficulty level is 4, the degree of importance is 21%, and the estimated cost is 18%.
The use of protein binder from shaving waste for leather finishing: Judging from the physical, chemical, and morphological properties of lizard skin leather
Authors: Sutyasmi S , Pahlawan I F , Griyanitasari G
Published: September 2019

Shaving waste is the tanned hides/skins shavings produced by the leather tanning industry. The waste is very polluting the environment because it contains chromium, difficult to degrade, large in volume and light in weight. Therefore it is difficult to handle for the leather tanning industry. The purpose of this study was to deal with the problem of shaving waste which was very polluting the environment and to evaluate the effect of the application of protein binders made from the shaving waste on physical, chemical, and morphological properties of the lizard skin leather. The shaving waste was hydrolysed using NaOH and separated by filtering the results of the hydrolysis. Filter results were tested as protein binder and used for lizard skin leather finishing. The lizard skin leather was then finished with a variation of the protein binder 1:1, 1:3, and 1:5. Then, the leather was tested physically, chemically, and morphologically. The results of the organoleptic test showed that all variations were almost the same and met the requirement of Indonesian Standard on the quality of chrome-tanned snake finished leather (SNI 06-4586-1998). For the physical properties, all parameters met the requirement of SNI, except for elongation. Chemical tests results showed that all of the parameters met the requirement. Morphologically, it showed that the greater the ratio between the protein binder and water, the smoother the morphology of the surface.