Agus Maman Abadi

Universitas Negeri Yogyakarta | UNY · Department of Mathematics Education

An earthquake is a big disaster that might cause a large amount of loss. Various ways had been proposed to overcome this situation, including the usage of catastrophe bonds. In this study, we propose an earthquake catastrophe bond in which both the coupon payment and principal payment are affected by the occurrence of earthquakes during the period....

Generalization of “DKN Fuzzy Simpleks” application program was developed to solve trapezoidal fuzzy linear program (FLP) with an objective function to maximize. The method used in this application is fuzzy simplex. The research stage begins by examining the classical simplex method and fuzzy simplex. Both methods are adopted to arrange the algorith...

In this paper we construct one type of de bruijn sequence. First, we modify the prefer-one and prefer-zero algorithm to build one cycle. The other cycles are constructed by modified pure circulating register. Finally, we use cycle joining method to get the full length of the sequence.

Macronutrients consist of energy, carbohydrates, proteins, and fats. Macro substances are nutrients containing calories or energy and are needed in large quantities. They serve to maintain body functions and run daily activities. Meanwhile, micronutrients are needed in small quantities. The group of micronutrients is vitamins such as vitamins A, B,...

This research was aimed to determine a ranking function of generalized trapezoidal fuzzy number and the optimum solution of a generalized trapezoidal fuzzy numbers linear programming problem using generalized fuzzy simplex method. The results of this research: we have defined a ranking function of thegeneralized trapezoidal fuzzy numbers Ä = (a, b,...

Transformer's efficiency is essential and significantly affects the transformer's performance in delivering power. The efficiency is affected by copper losses, of which value is not constant. To improve a state-owned electricity company in Indonesia (PLN) in increasing the optimization of transformer loading, a more accurate calculation of transfor...

This study aims to obtain a mapping of seismic hazard vulnerability of Special Region of Yogyakarta (DIY) using the Fuzzy Simple Additive Weighting (FSAW) method. This mapping is serves as an act of mitigation for earthquake disasters to reduce the risk of earthquake disasters and minimize fatalities or losses in earthquake-prone areas. The factors...

Cardiovascular disease is the leading cause of death in the world, so early detection of heart conditions is very important. Detection related to cardiovascular disease can be conducted through the detection of heart signals interference, one of which is called phonocardiography. This study aims to classify heart disease based on phonocardiogram (P...

This study aims to determine the drought risk of Kulon Progo Regency using fuzzy logic and study the characteristics. The input variables used in this study are the drought level, exposed population, and vulnerable population. The Mamdani method used in the fuzzy inference to obtain the output variable, that is, the Drought Risk Index (DRI). Then,...

This article deals with problems of detecting abrupt changes in time series ba Change Point Model (CPM) framework. We propose a fuzzification in a Fuzzy Time Series (FTS) model to eliminate a trend in a contaminated dependent series. The independent residuals are then inputed on the CPM method. In simulating an abrupt change, an ARIMA(1,1,1) and va...

Water saturation is one important factor in determining the hydrocarbon content in a rock where the less water content in the rock affects the greater the number of hydrocarbons. The purpose of this study is to determine water saturation at various depths in drilling using fuzzy logic. Input variables used are depth, effective porosity, effective p...

The agricultural sub-sector that has the potential to develop is the plantation sub-sector. The plantation sub-sector contributes around 3.57% in GDP. Plantation sub-sector commodities whose growth is very rapid are oil palm which is the basic ingredient in making palm oil (CPO). The world need for oil and vegetable fats which continues to increase...

Choosing the type of airline tickets is determined by several factors, including types of direct or transit flights, ticket prices, facility and travel time. The purpose of this research is to determine the decision to purchase the direct and transit type airline tickets. In this research, the data were collected from Yogyakarta-Jakarta (Round Trip...

Unemployment is a very common problem in developing countries such as Indonesia. One of the government’s efforts to overcome the problem is having skill training. However, the labor often faced difficulties in classifying unemployment in Indonesia. Therefore, the utilization of fuzzy logic is considered as an appropriate way to examine the state’s...

Universitas Negeri Yogyakarta is one of the state universities in Indonesia that assigned Student’s Single Tuition Fee (UKT) policy. UKT is an Indonesian government policy of tuition fees charged to every student with nominal based on the student’s financial capabilities. Although the implementation of UKT nominal has been arranged in such ways, th...

This study aims to analyze the difficulty of VIIIth grade junior high school students in circle material reviewed from mathematical connection ability. The method used in this research is descriptive qualitative with a case study approach. The subjects in this study were 23 eight grade in one of the junior high schools in Temanggung. Data collectio...

The traffic control system is a system that functions to regulate and control traffic flow at crossroads, pedestrian crossings (zebra crossing) and other traffic flows. A good traffic control system is a system that is able to adjust the duration of the traffic lights with the density of traffic flow automatically. In big cities like Yogyakarta, tr...

The presidential and vice presidential elections held every five years is a benchmark for democracy in Indonesia. However, the expected level of participation cannot be achieved. Election socialization as an effort to increase the level of participation in each province is different because the level of participation in each province is also varied...

This study aimed to find out the difficulties of proof experienced by undergraduate students. The type of research used was descriptive case studies. This research was conducted on 12 junior undergraduate students of the Mathematics Education Department at one of the universities in Yogyakarta. Data in this study were obtained through diagnostic te...

Discoveries related to information and communication technologies change the viewpoints of humans against the world including the world of education. The role of technology supports many activities, especially learning activities, and it also can support the learning process. Education systems in the globalization era show the transformation which...

The growth of manufacturing and waste disposal in the Gajahwong River watershed has resulted in decreasing river water quality. Therefore this study aims to develop a fuzzy logic system in classifying water quality status in Gajahwong River. There are 11 parameters used for classifying water quality status, namely temperature, potential hydrogen (p...

Penelitian ini bertujuan untuk mengestimasi atau memprediksi harga nikel menggunakan sistem fuzzy metode Mamdani dan mendeskripsikan tingkat keakuratan sistem yang dibentuk. Data yang digunakan data harga nikel dunia 4 tahun terakhir yaitu data mulai Januari 2014 sampai Desember 2017. Sistem Fuzzy Mamdani diawali dengan pembagian data menjadi train...

Heart disease is the leading cause of death in the world. Heart disease is called the silent killer, because it often occcurs suddenly. Therefore, periodic cardiac examination is very necessary to reduce cases of death from heart disease.Heart disease can be known through electrocardiogram (ECG) examination. This study aims to explain the process o...

[English]: This article aims to elucidate the effectiveness of Missouri mathematics project-problem solving learning (MMP-PS) toward mathematical reasoning ability and self-efficacy. We conducted quasi-experiment research which involves 132 lower secondary school students (age 14-15 years old) as the population. Of the population, 25 students respe...

Penelitian ini bertujuan untuk mendeskripsikan mana yang lebih efektif antara PBL setting kolaboratif kelompok dan berpasangan ditinjau dari prestasi belajar aljabar, kemampuan berpikir kritis, dan kecemasan siswa. Penelitian ini adalah penelitian quasi eksperimen dengan desain pretest-postest nonequivalent comparison-group design. Populasi dalam p...

The suspension system is part of motorcycle that serves to absorb vibration and shocks of the road surface so as to improve the safety and comfort while driving. Motorcycle typically use double shockbreaker system which analogous to a two-spring system arranged in parallel. The aim of this researh is to analyze the model of the model of double shoc...

This study aims at describing mathematical literacy skill, mathematical reasoning skill, self esteem and the relationship of them. Participants of the research were 37 tenth-grade students randomly selected from a public high school. Data collected through mathematical literacy skill test, mathematical reasoning skill test, and self esteem question...

The study aims to investigate the most optimum rules of fuzzy inference systems to forecast the white sugar price in the international market. The fuzzy rules are optimized by using a table look-up method. As a comparison, we also employ fuzzy time series methods that developed by Chen, Singh, and Heuristic. The main differences among the four meth...

This research aimed at determining student errors in completing abstract algebra tasks. This study can be catagorized as descriptive research involving 31 college students of mathematics education program as research participant, Riau Kepulauan University, Batam. The research instrument used 4 essays of abstract algebra tests. The students' errors...

Fuzzy inference system is a soft computing model which has been widely applied to build a prediction model. This model applied the fuzzy sets theory and believed providing high accuracy for prediction. This study aims to construct the fuzzy inference model to predict the percentage of poor population in Indonesia based on unemployment rate and Gini...

This study aims to determine the development of mathematic learning device with metacognitive approach which is oriented to the ability of mathematical literacy and mathematical attitude that is valid, practical and effective. Learning device development model refers to the Plomp Model which has 3 steps: preliminary stage, development or prototypin...

This research aimed to describe mathematical communication ability of students viewed from self-efficacy. This research was descriptive qualitative research. Subjects in this research were students of eight grade SMP Negeri 1 Marioriawa Kabupaten Soppeng Sulawesi Selatan. The data were collected by a test, questionnaire, and interview. Data analysi...

Nutrition is a major health problem and concern for parents when it is relating with their toddler. The nutritional status is an expression of the state caused by the status of the balance between the number of intake of nutrients and the amount needed by the body for a variety of biological functions. The indicators that often used to determine th...

Seismic data is usually modelled using autoregressive processes. The aim of this paper is to find the arrival times of the seismic waves of Mt. Rinjani in Indonesia. Kitagawa algorithm’s is used to detect the seismic P and S-wave. Householder transformation used in the algorithm made it effectively finding the number of change points and parameters...

Hydrocarbon prospective zone is a certain layer in a reservoir which is estimated producing oil. The geologists use the qualitative analysis method to find the prospect layers. The research used five variables modeled by three fuzzy membership functions and eight rules of fuzzy logic. The rules cause insensitiveness in the working system. This stud...

The Increasing need of storing large amounts of data presents a new challenge. One way to address this challenge is to use distributed data storage system. One of the strategies implemented in the distributed data storage system is using the technique of regenerating code. The code used in this technique is based on the algebraic structure of field...

The purpose of this research was to produce instructional package in 7 th grade on the 2 nd semester with POGIL that consisted of lesson plans and student worksheets, which hadgood quality. The quality was determined based on Nieveen criteria, including validity, practicality, and effectiveness. This study was a development research. The developing...

The increasing need in techniques of storing big data presents a new challenge. One way to address this challenge is the use of distributed storage systems. One strategy that implemented in distributed data storage systems is the use of Erasure Code which applied to network coding. The code used in this technique is based on the algebraic structure...

Penelitian ini bertujuan untuk mendeskripsikan: (1) keefektifan model pembelajaran kooperatif tipe Jigsaw ditinjau dari kemampuan penalaran dan sikap belajar matematika, (2) keefektifan model pembelajaran kooperatif tipe TAI ditinjau dari kemampuan penalaran dan sikap belajar matematika, (3) model pembelajaran yang lebih efektif antara tipe Jigsaw...

Penelitian ini bertujuan untuk mendeskripsikan keefektifan pendekatan pembelajaran (problem solving dengan setting kooperatif dan problem posing dengan setting kooperatif) dan membandingkan keefektifan pendekatan problem posing dengan setting kooperatif dan pendekatan problem solving dengan setting kooperatif pada pembelajaran matematika ditinjau d...

The neuro fuzzy model is a model that combines fuzzy and neural network, which has been applied to time series forecasting. A singular value decomposition method can be utilized for optimization of the neuro-fuzzy model based on the singular values of the matrix. This research aims to forecast the number of train passengers of PT Kereta Api Indones...

Penelitian ini bertujuan untuk mendeskripsikan keefektifan pembelajaran cooperative learning (type student team achiement division dan type think-pair-share) dan keefektifan pembelajaran coope-rative learning type student team achiement division dibandingkan dengan pembelajaran cooperative lerning type think-pair-share ditinjau dari aspek ketercapa...

Tujuan dari penelitian ini adalah untuk mengetahui: (1) pengaruh motivasi, self-efficacy, dan latar belakang pendidikan terhadap prestasi matematika mahasiswa PGSD dan PGMI. (2) perbedaan pengaruh motivasi, self-efficacy, dan latar belakang pendidikan terhadap prestasi matematika maha-siswa PGSD dan PGMI. Jenis penelitian ini adalah penelitian surv...

Recently, many researchers in the field of writing about the prediction of stock price forecasting, electricity load demand and academic enrollment using fuzzy methods. However, in general, modeling does not consider the model position to actual data yet where it means that error is not been handled optimally. The error that is not managed well can...

Many scientists have been studied time series modeling using fuzzy method. Fuzzy method has an advantage in time series modeling because it permits linguistic variable as an input, namely economists' experiences. This paper discusses model transformation in the extent of median error. Sliding the model in the extent of median error directing to zer...

The aims of this research are to construct a new method for modeling fuzzy time series data and to apply the method for forecasting Indonesian inflation rate. The procedure of this research is done by the following steps: (1) determine fuzzy relations using table lookup scheme, (2) Apply the singular value decomposition to reduce the unimportant fu...

Tujuan penulisan artikel ini adalah untuk mendapatkan rancangan kendali logika fuzzy guna menggantikan kendali proportional integral derivative power system stabilizer pada sistem eksitasi.

Tujuan penulisan ini adalah untuk memperkirakan tingkat inflasi di Indonesia. Jika data-data tentang nilai tukar rupiah dan pendapatan nasional dipandang sebagai input data, kemudian tingkat inflasi di Indonesia dipandang sebagai output data, maka akan dibuat suatu model untuk output data berdasarkan input data tersebut dengan menggunakan sistem fu...

In fuzzy modelling, Wang's method is a simple method that can be used to overcome the conflicting rule by determining each rule degree. The weakness of fuzzy model based on the method is that the fuzzy relations may not be complete so the fuzzy relations can not cover all values in the domain. Generalization of the Wang's method has been developed...

A time series is a realization or sample function from a certain stochastic process. The main goals of the analysis of time series are forecasting, modeling and characterizing. Conventional time series models i.e. autoregressive (AR), moving average (MA), hybrid AR and MA (ARMA) models, assume that the time series is stationary. The other methods t...

Abstrak Tujuan penulisan ini adalah untuk memprediksi tingkat inflasi di Indonesia dengan menggunakan model neuro fuzzy, yaitu ANFIS (adaptive neuro fuzzy inference system). Pada penelitian ini, data inflasi sebelumnya dan faktor-faktor yang mempengaruhi inflasi yaitu nilai tukar rupiah (kurs) dan tingkat suku bunga (BI rate) dipandang sebagai inpu...

In fuzzy modeling, table lookup scheme (Wang's method) is a simple method that can be used to overcome the conflicting rule by determining each rule degree. The weakness of fuzzy model based on the method is that the fuzzy rules may not be complete so the fuzzy rules can not cover all values in the domain. Generalization of the Wang's method has be...

Inflation rate is one of some indicators that could be used to taking policy for government. If the inflation rate is not controlled, then it could cause the instability of Indonesian economy. The aim in this paper is to estimate the inflation rate using fuzzy system. Interest rate, exchange rate of rupiah to US dollar, gross national product and m...