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Is Fatimah
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Faculty of Mathematics and Natural Sciences Universitas Islam Indonesia Jl. Kaliurang Km 14, Ngaglik, Sleman, Yogyakarta, 55584
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INDONESIA
EKSAKTA: Journal of Sciences and Data Analysis
Published by Universitas Islam Indonesia
ISSN : 27160459     EISSN : 27209326     DOI : 10.20885
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Earth & Planetary Sciences Materials Science & Nanotechnology
Ekstakta is an interdisciplinary journal with the scope of mathematics and natural sciences that is published by Fakultas MIPA Universitas Islam Indonesia. All submitted papers should describe original, innovatory research, and modelling research indicating their basic idea for potential applications. The Journal particularly welcomes submissions that focus on the progress in the field of mathematics, statistics, chemistry, physics, biology and pharmaceutical sciences.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 196 Documents
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Visitor Behavior in the Library of Syiah Kuala University based on Their Visiting Time Duration Samsul Anwar; Afriyani Afriyani; Putri Shalihatul Ula; Isra Safriana; Ida Fajri; Reza Ariska
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 17, ISSUE 2, August 2017
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol17.iss2.art4

Abstract

The main requirements in the application of survival analysis are the starting time and the ending time of an event. Thus, the duration of visiting time in the Library of Syiah Kuala University (Unsyiah) Banda Aceh could be analyzed by using survival analysis. This study obtained primary data through an interview with the visitors of Unsyiah’s library. Total Samples were 105 visitors collected from three different floors of the library that is 35 visitors from each floor. The analysis was divided into two main steps. The first step was estimating the probability distribution of the visit time duration data through graphical analysis. The second step was calculating the probability density function (PDF), cumulative density function (CDF), survival, and hazard function of the data based on the appropriate distribution in the first step.
Model Analysis of Motorcycle Suspension System Using the Fourth Order of Runge-Kutta Method Umi Nurofi’atin; Agus Maman Abadi
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 18, ISSUE 2, August 2018
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol18.iss2.art3

Abstract

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 shockbreaker motorcycle suspension system that working without outside force using passive suspension system. The data used are from damper tester experiment, then model analyzed using analytical method and the fourth order of numerical Runge-Kutta method. This research use shockbreaker observation datas that is the measurment data of spring constant and damping constant by performing damper tester using 4 different loads. The process model analysis using Matlab R2013a. Input variables are spring constant, damping constant, and the mass of the load. Methods of analysis using analytical method and the fourth order of Runge-Kutta method. While the resulting outputs are 2 spring constants, change the length of the spring, damping ratio, the optimal damping of the suspension, and the spring deflection chart against time. This model motorcycle suspension system uses solution of differential equations for the under damped suspension condition, that is the suspension system will be insulated a few moments before reaching the equilibrium position. Therefore, the resulting damping rate of the motorcycle is not optimal yet. This study found the optimal damping for each model of the suspension system. The level of accuracy of the fourth order of runge-kutta method for model analysis of the suspension system is quite high with error <0.1 and the timing of analysis is faster than the analytic method. Future research may use other methods or other input variables for more accurate analysis results.
Diagnosing Heart Disease using Wavelet Transformation and Adaptive Neuro Fuzzy Inference System (ANFIS) Based on Electrocardiagram (ECG) Indah Puspita; Agus Maman Abadi
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 19, ISSUE 1, February 2019
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol19.iss1.art7

Abstract

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 of diagnosing heart disease through ECG using wavelet transformation and Adaptive Neuro Fuzzy Inference System (ANFIS).The process of diagnosing heart disease begins with cutting ECG signal consisting of 9-11 waves into one ECG wave, then decomposition and extraction are performed using wavelet transformation to obtain 6 parameters. The parameters will be used as input in ANFIS model. Data obtained from ECG extraction are divided into 70% training data and 30% testing data The output from the ANFIS model is a diagnosis of heart diseases, such as left bundle branch block (LBBB),  right bundle branch block (RBBB), and normal. ANFIS learning is divided into 6 stages, namely clustering data with Fuzzy C-Means method, computing the degree of membership of each data, determining fixed neurons, looking for normalized firing strength, calculating the consequent parameter values, and determining network output.The results of the study obtained the best ANFIS model with 10 clusters. The level of accuracy, specificity, and sensitivity for training data is 100%, 100%, and 100%, respectively and for the testing data, the level of accuracy, specificity, and sensitivity is 100%, 100%, and 100%, respectively.
Adsorption Competition between H+ and Cd2+ Ions Toward Active Sites on Ionic Imprinted Mercapto-Silica Hybrid Buhani Buhani
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 12, ISSUE 1, February 2011
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Adsorption process on Cd2+ionic  imprinted mercapto-silica hybrid material  (Cd(II)-IIP HMS) has been carried out with studying an adsorption competition between ion H+ and Cd2+ ion upon active sites of Cd(II)-IIP HMS material.  Characterization of surface material was based on specific surface area, total volume, and porous diameter.  Cd(II)-IIP HMS material with template ionic concentration of each 0.107; 0.214; 0.429; 0.658 mmol g-1 shows  that adsorption model  is relatively similar, the higher of H+ ion competed,  the  lower of adsorption capacity of Cd(II)-IIP HMS material upon Cd2+ ion.  Keywords: adsorption, active site, mercapto-silica hybrid, ionic imprinted
Characterization of Newcastle Disease Virus in Southeast Asia and East Asia: Fusion Protein Gene Arif Nur Muhammad Ansori; Viol Dhea Kharisma
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 1, ISSUE 1, February 2020
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/EKSAKTA.vol1.iss1.art3

Abstract

The aim of this study was to generate the bioinformatics analysis of the circulating NDVs in Southeast Asia, East Asia, and the vaccine virus strains through a database of isolates stored in GenBank® (National Center for Biotechnology Information, USA). The used isolates were AJ629062.1 (La Sota), AF309418.1 (B1), EF201805.1 (Mukteswar), KT445901.1 (Komarov), JX524203.1 (V4), AY935499.2 (I-2), KC987036.1 (F), KF767104.1 (Indonesia), KF767105.1 (Indonesia), KF767106.1 (Indonesia), HQ697255.1 (Indonesia), HQ697256.1 (Indonesia), HQ697261.1 (Indonesia), JX012096.2 (Malaysia), GU332646.1 (Vietnam), AF358786.1 (Taiwan), AF358788.1 (China), KT380032.1 (Republic of Korea), and KC503416.1 (Japan). As the results, this study have revealed the data of homology, pathotype, genetic distance, B cell epitope prediction, and molecular phylogenetic analysis of circulating NDVs in Southeast Asia and East Asia and vaccine virus strains. Thus, the results of this study can be used as a reference for vaccine design studies in the applications of poultry vaccine industryReceived: 28 August 2019; Accepted: 31 December 2019; Published: 11 January 2020.
Optimasi dan evaluasi rutin ICP QMS untuk analisis multi-unsur Noor Fitri
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 12, ISSUE 2, August 2011
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Telah dilakukan optimasi dan evaluasi rutin alat Inductively Coupled Plasma Quadrupole Mass Spectrometer (ICP-QMS) untuk menganalisis multi unsur. Fokus optimasi adalah mendapatkan kondisi parameter yang memberikan intesitas sinyal optimum pada rentang analisis skala ppm hingga ppt. Evaluasi rutin bertujuan untuk mengetahui efektivitas optimasi harian dan bulanan alat ICP QMS agar mendapatkan kinerja alat yang unggul dengan akurasi dan presisi tinggi terutama untuk analisis multi-unsur dalam material biologis.Kata kunci: Optimasi, ICP QMS, multi-unsur
Studi Simulasi Model Nested Logit dan Paired Combinatorial Logit pada Respon Multinomial Jaka Nugraha
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 13, ISSUE 1-2, August 2013
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol13.iss1-2.art8

Abstract

Multinomial logit model (MNL) is based on independent irrelevant alternatives assumption. If there was a correlation, MNL would result bias estimator. Correlation among of choices could be accommodated by Nested logit Model (NL) and Paired Combinatorial Logit Model (PCL). This research discuss how NL and PCL model can be used for estimating parameters (regression coefficient and correlation) and comparing to MNL in discrete choice model. Correlation structure is tested nesting correlation and correlation overlap. Paramaters in the models are estimated using maximum likelihood method. Simulated data generated using software R.3.0.1. Based on simulations data with nested correlation, NL model more appropriate than do MNL. But on data with overlapping correlation, the maximum likelihood estimator is not unique.Keywords : Multinomial logit, Nested logit, Paired Combinatorial Logit, maximum likelihood
Identifikasi Morfologi dan Uji Aktivitas Antimikroba Terhadap Bakteri Escherichia coli Dari Fermentasi Buah Markisa (Passiflora sp.) Habibi Hidayat
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 15, ISSUE 1-2, 2015
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol15.iss1-2.art8

Abstract

Telah dilakukan studi identifikasi bakteri dari buah Markisa dan uji aktivitas antimikroba terhadap bakteri Escerichia coli. Sampel yang digunakan dalam penelitian ini berasal dari buah Markisa, dimana penelitian ini bertujuan untuk mengidentifikasi morfologi bakteri yang tumbuh dalam proses fermentasi buah markisasecara mikroskopik, dan uji aktivitas antimikroba dari hasil fermentasi Markisa (Passiflora Sp.) terhadap bakteri Escerichia coli. Identifikasi morfologi yang dilakukan dengan metode pewarnaan Gram dan uji aktivitas antimikroba dengan menggunakan metode cakram. Hasil yang diperoleh dari terhadap kedua isolat yaitu S1 berbentuk basil dan S2 berbentuk basil dan kokus. Perhitungan jumlah koloni pada pengenceran 10-7 diperoleh S1 sebanyak 16.107 cfu/ml dan S2 sebanyak 30.107 cfu/ml. Uji aktivitas antimikroba terhadap bakteri patogen Escerichia coli selama 1 x 72 jam yaitu isolat S1 diperoleh zona hambat pertumbuhan bakteri sebesar 11 mm, 13 mm dan 15 mm dan isolat S2 sebesar 13 mm, 14 mm dan 16 mm.
Synthesis and Characterization of 2,3,4-Trihydroxy-5-methyl Xanthone as Antimalarial Compound Dhina Fitriastuti; Jumina Jumina; Priatmoko Priatmoko
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art4

Abstract

Synthesis of xanthone derivatives had been conducted to obtain new antimalaria active compounds. The characterization of the synthesized xanthones was also conducted. Synthesis of xanthone was conducted from the raw material of hydroxybenzoic acid and phenol derivatives using Eaton's reagent via acylation-dehydration reaction by modified Grover, Shah and Shah (GSS) method. The synthesis of 2,3,4-trihydroxy-5-methyl xanthone was carried out using gallic acid, o-cresol and Eaton's reagent.The mixture was heated for 3 h at 80 °C to yield 2,3,4-trihydroxy-5-methyl xanthone in 43% yield as dark red viscous liquid. The results of IR, 1H-NMR and 13C-NMR analysis of sampleshowed that the compound2,3,4-trihydroxy-5-methyl xanthonehas successfully synthesized.
Synthesis of Metal and Metal Oxide Nanoparticles Using Plant Extract: a Review Is Fatimah
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 17, ISSUE 1, February 2017
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol17.iss1.art7

Abstract

Nanotechnology is an emerging technology and it is related to various applications. Related to nanotechnology development, the use of green chemistry concept, low cost technology and sustainability is a must. Synthesis of nanoparticles using plant extract is a developing technique within the scheme. In this paper, study on metal/metal oxide synthesis and its aspects is presented for describing the potency of natural resources for nanoparticle synthesis within green chemistry approach.

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