http://ejournal.uin-malang.ac.id/index.php/Math/issue/feedCAUCHY: Jurnal Matematika Murni dan Aplikasi2022-08-04T01:42:36+07:00Juhari, M.Sicauchy@uin-malang.ac.idOpen Journal Systems<h3>CAUCHY: Jurnal Matematika Murni dan Aplikasi</h3><p><span lang="id"><span class="hps"><strong>p-ISSN: <a href="http://u.lipi.go.id/1255061534" target="_blank">2086-0382</a> | e-ISSN: <a href="http://u.lipi.go.id/1447468580" target="_blank">2477-3344</a></strong></span></span><strong></strong></p><p><strong><span lang="id"><span class="hps"><br /></span></span></strong><span id="result_box" lang="en"> <strong>CAUCHY: Jurnal Matematika Murni dan Aplikasi</strong> <span>is a</span> <span>mathematical international journal</span> <span>published</span> <span>twice a year</span> <span>in May</span> <span>and</span> <span>November</span> <span>by</span> <span>the Mathematics</span> Department, F<span>aculty of</span> <span>Science</span> <span>and</span> T<span>echnology, </span><span>Universitas Islam Negeri Maulana Malik Ibrahim Malang</span></span></p><p><span id="result_box" lang="en"><strong>CAUCHY: Jurnal Matematika Murni dan Aplikasi </strong><span><strong>has been accredited Second Grade " SINTA 2" Ministry of Research and Technology/National Agency for Research and Innovation, Republic of Indonesia</strong></span><strong> (<a title="SK Akreditasi Jurnal 2020" href="https://drive.google.com/open?id=1v2Hrnf5azymhkZJRR4Jdqy_CoNTjtyjS" target="_blank">SK: 85/M/KPT/2020) since April 1, 2020</a>.</strong></span></p><p><span lang="en">We welcome authors for original articles (research), review articles, interesting case reports, special articles illustrations that focus on the <strong>Pure and Applied <strong>Mathematics.</strong></strong></span></p><p>Subjects suitable for publication include, the following fields of:</p><ul><li>Fuzzy Systems and its Applications</li><li>Geometry Theories and its Applications</li><li>Graph Theories and its Applications</li><li>Real Analysis and its Applications </li><li>Operation Research and its Applications</li><li>Statistical Theories and its Applications</li><li>Dinamical Systems and its Applications</li><li>Mathematical Modeling and its Applications</li><li>Discrete Mathematics and its Applications</li><li>Computer Mathematics and its Applications</li><li>Actuarial Mathematics and its Applications</li></ul><p><span lang="en"><span><strong>Journal History</strong><br />CAUCHY: Jurnal Matematika Murni dan Aplikasi has several changes and updates in its history as follows: 1). On 2009-2012, the cover color was changed from yellow to purple; 2). On 2013-2015, it used two-column system for the layout; 3). From 2016, it uses one-column layout and each article submitted to CAUCHY has to be written in English.</span></span></p><strong><span lang="en"><span id="result_box" lang="en"><span id="result_box" lang="en"><span> <a href="http://s1153.photobucket.com/user/joehari1/media/new1.gif.html" target="_blank"><img src="http://i1153.photobucket.com/albums/p503/joehari1/new1.gif" alt=" photo new1.gif" border="0" /></a> </span></span></span><span id="result_box" lang="en"><span id="result_box" lang="en"><span>Starting from Vol</span><span>.</span> <span>4 No.</span> <span>2</span> <span>(2016)</span> <span>CAUCHY: Jurnal Matematika Murni dan Aplikasi</span> <span>use a new layout template</span></span><br /></span></span></strong><p>Registration and article submission guidelines can be downloaded <a href="https://goo.gl/crrzlC" target="_blank">here</a>.</p><p><span lang="id"><span class="hps"><br /></span></span></p>http://ejournal.uin-malang.ac.id/index.php/Math/article/view/16019Front-Matter2022-05-12T02:51:11+07:00Front Mattercauchy@uin-malang.ac.id2022-05-01T00:00:00+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/16020Back-Matter2022-05-12T02:52:37+07:00Back Mattercauchy@uin-malang.ac.id2022-05-01T00:00:00+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12938A Note on Generalized Strongly p-Convex Functions of Higher Order2022-08-04T01:35:43+07:00Corina Karimco_mathub@ub.ac.idEkadion Maulanarm.ekadion.m@gmail.com<p class="Abstract">Generalized strongly -convex functions of higher order is a new concept of convex functions which introduced by Saleem <em>et al.</em> in 2020. The Schur type inequality for generalized strongly -convex functions of higher order also studied by them. This paper aims to revise Schur type inequality for generalized strongly -convex functions of higher order in their paper. In order to revise it, we show that the contradiction was true. This paper showed that Schur type inequality for generalized strongly -convex functions of higher order previously<em> </em>is not valid and we give the correct Schur type inequality for generalized strongly -convex functions of higher order</p>2022-03-11T01:42:39+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13097The Generalized STAR Modeling with Heteroscedastic Effects2022-08-04T01:42:36+07:00Utriweni Mukhaiyarutriweni@math.itb.ac.idSyahri Ramadhaniririramadhani2@gmail.com<p class="Abstract">In general, the Generalized Space Time Autoregressive (GSTAR) model of space-time assumes constant error variance. In this study, a GSTAR model was built with an error variance that was not constant or had a heteroscedasticity effect, namely the combination of GSTAR–Autoregressive Conditional Heteroskedasticity (ARCH). The parameters of the GSTAR–ARCH model were estimated using the Generalized Least Square (GLS) method to obtain an efficient parameter estimation. As a case study, the GSTAR–ARCH model was applied to the daily mean wind speed data of New Orleans, Florida and Mississippi to predict the occurrence of Hurricane Katrina that occurred in 2005. The results obtained show that the GSTAR model (3;0,0,1)–ARCH(1) predicts Hurricane Katrina very well.</p>2022-03-11T01:42:41+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13184Optimal Control and Cost-Effectiveness Analysis in An Epidemic Model with Viral Mutation and Vaccine Intervention2022-03-11T01:48:32+07:00Yudi Ari Adiyudi.adi@math.uad.ac.idNursyiva Irsalindanursyiva.irsalinda@math.uad.ac.idMeksianis Z Ndiimeksianis.ndii@staf.undana.ac.id<p class="Abstract">This paper introduces an optimal control problem in a two-strain SIR epidemic model with viral mutation and vaccine administration. The purpose of this study was to investigate the efficacy and cost-effectiveness of two disease prevention strategies, namely restriction of community mobility to prevent disease transmission and vaccine intervention. We consider the time-dependent control case, and we use Pontryagin’s Maximum Principle to derive necessary conditions for the optimal control of the disease. We also calculate the Average Cost-Effectiveness Ratio (ACER) and the Incremental Cost-Effectiveness Ratio (ICER) to investigate the cost-effectiveness of all possible strategies of the control measures. The results of this study indicate that the most cost-effective disease control strategy is a combination of mobility restriction and vaccination.</p>2022-03-11T01:42:42+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13266An Application of Geographically Weighted Regression for Assessing Water Polution in Pontianak, Indonesia2022-03-11T01:48:32+07:00Naomi Nessyana Debatarajanaominessyana@math.untan.ac.idDadan Kusnandardkusnand@untan.ac.idRossie Wiedya Nusantararwiedyanusantara@gmail.comGeographically weighted regression (GWR) is an exploratory analytical tool that creates a set of location-specific parameter estimates. The estimates can be analysed and represented on a map to provide information on spatial relationships between the dependent and the independent variables. A problem that is faced by the GWR users is how best to map these parameter estimates. This paper introduces a simple mapping technique that plots local t-values of the parameters on one map. This study employed GWR to evaluate chemical parameters of water in Pontianak City. The chemical oxygen demand (COD) was used as the dependent variable as an indicator of water polution. Factors used for assessing water pollution were pH (X1), iron (X2), fluoride (X3), water hardness (X4), nitrate (X5), nitrite (X6), detergents (X7) and dissolved oxygen, DO, (X8). Samples were taken from 42 locations. Chemical properties were measured in the laboratory. The parameters of the GWR model from each site were estimated and transformed using Geographic Information Systems (GIS). The results of the analysis show that X1, X2, X3, X5, and X7 influence the amount of COD in water. The resulting map can assist the exploration and interpretation of data.2022-03-11T01:42:43+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13323Richards Curve Implementation For Prediction of Covid-19 Spread in Maluku Province2022-03-11T01:48:33+07:00Nanang Ondinoemail@gmail.comFrancis Yunito Rumlawangrumlawang@yahoo.comYopi Andry Lesnussayopi_a_lesnussa@yahoo.comCOVID-19 (Coronavirus Disease 2019) was first reported in Wuhan city, China at the end of December 2019 and spread to Indonesia specifically in Maluku Province at the end of March 2020. This study aims to predict the spread of COVID-19 cases in Maluku province as well as explore the phases of its spread using the Richards Curve which is an extension of the Logistic Curve. After estimating the parameters of the Richards Function with cumulative case data of COVID-19 in Maluku province from March 23 to November 4, 2020, the results of the spread of COVID-19 cases in Maluku province reached a turning point on October 22, 2020, and ended on May 25, 2023, with a total cumulative case of 9,451 cases2022-03-11T01:42:43+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13351The Properties of Intuitionistic Anti Fuzzy Module t-norm and t-conorm2022-03-11T01:48:33+07:00Ongky Denny Wijayaongkydenny@gmail.comAbdul Rouf Alghofariabdul_rouf@ub.ac.idNoor Hidayatnoorh@ub.ac.idMohamad Muslikhmslk@ub.ac.idZadeh have introduced fuzzy set in 1965 and Atanassov have introduced intuitionistic fuzzy set in 1986 in theirs paper. Now, many of researcher connecting intuitionistic fuzzy set with algebraic structure. We interested to combine some concepts over intuitionistic fuzzy set, module of a ring, t-norm, t-conorm, and intuitionistic anti fuzzy. In this paper, we discusses about intuitionistic anti fuzzy module t-norm and t-conorm (IAFMTC) and their properties with respect to module homomorphism, maps, pre-image, and anti-image from intuitionistic fuzzy sets. We have investigate all properties of IAFMTC.2022-03-11T01:42:44+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13356Analysis of Insurance Customer Factors to Renewal Using Hybrid AHP-FTOPSIS2022-03-11T01:48:33+07:00Kwardiniya Andawaningtyasdina_math@ub.ac.idEvi Ardiyanieviardiyani98@gmail.comCorina Karimcorinaub@gmail.com<p>Human life is full of uncertainty that has enormous risks. Insurance is a one of methods that can help humans reduce those risks. Human needs for insurance causes competition among insurance companies in Indonesia to become very competitive. One factor that makes insurance companies to compete is to have its customers who make insurance renewals. Thesis discusses analysis of factors that influence insurance renewal using<em> Analytical Hierarchy Process </em>(AHP) method and the ranking of customer’s favorite insurance for renewal using the <em>Fuzzy Technique for Order Preference by Similarity to Ideal Solution</em> (FTOPSIS) method. Five criteria have been determined with each criterion having subcriteria in this study. AHP method is used to calculate the weight of criteria and to determine the factors that influence customers the most to do renewal. The FTOPSIS method is used to determine the best alternative. The results of the analysis using these methods conclude was the main factor that influences the customers in conducting renewals is feature with the subcriteria of health protection needs. Meanwhile, the ranking of customer’s favorite insurance in conducting renewal is Takafulink Salam Cendikia with proximity coefficient value of 0,645, Takaful Al-Khairat with value 0,563, Takaful Dana Pendidikan with value 0,552, and Takafulink Salam with value 0,341</p>2022-03-11T01:42:45+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13371Average Based-FTS Markov Chain Based on a Modified Frequency Density Partitioning to Predict COVID-19 in Central Java2022-03-11T01:48:33+07:00Susilo Hariyantosus2_hariyanto@yahoo.co.idZaenurrohman Zaenurrohmanzaenurrohman8.zr@gmail.comTiti Udjiani SRRMudjianititi@yahoo.com<p>COVID-19 is still a pandemic in Indonesia, and Central Java is no exception. New positive cases of COVID-19 in Central Java are being discovered every day. Therefore, researchers try to predict new positive cases in Central Java. Many forecasting methods are currently developing, one of which is fuzzy time series (FTS). FTS has been also developed until now, one of which is a development of the FTS by combining the Markov chain as a defuzzification process. In FTS there is no definite formula to determine the length of the interval, so the researcher uses an average based to determine the length of the interval in the FTS Markov chain. Next, the researcher repartitioned based on the modified frequency density. The results of this study are that forecasting new positive cases of COVID-19 in Central Java using the average based-FTS Markov chain based on a modified frequency density partitioning method has a good level of accuracy, this can be seen from the MAPE value of the method.</p>2022-03-11T01:42:45+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13451Spatial Autoregressive Model of Tuberculosis Cases in Central Java Province 20192022-03-11T01:48:33+07:00Hasrat Ifolala Zebuahasrat20001@mail.unpad.ac.idI Gede Nyoman Mindra Jayamindra@unpad.ac.id<div><p class="Keywords">Tuberculosis is an infectious disease caused by infection with the bacterium Mycobacterium tuberculosis. Central Java is one of the three provinces with the highest tuberculosis cases in Indonesia. Some of the risk factors used in this research are the spatial lag of the number of tuberculosis cases representing the agent component, the morbidity rate representing the host component, population density, proper sanitation, and proper drinking water which represent environmental components. This study uses the Spatial Autoregressive (SAR) model. The SAR model is a regression model where the response variable has a spatial correlation. The estimation method usually used in SAR model is maximum likelihood. The value of Moran's I on the number of tuberculosis cases in Central Java is 0.499 and is significant, which means that there is a positive spatial autocorrelation. The model was chosen based on the LM test and AIC. The best model is the SAR model. The results of the analysis obtained show that the greater the number of tuberculosis cases is influenced by the number of tuberculosis cases in the surrounding area. Proper sanitation has a negative effect, on the contrary, the dense population has a positive effect on the number of tuberculosis cases in the province of Central Java.</p></div>2022-03-11T01:42:46+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13458Goodwin Model with Clustering Workers' Skills in Indonesian Economic Cycle2022-03-11T01:48:34+07:00Sri Lestari Mahmudsri.lestari@ung.ac.idResmawan Resmawanresmawan@ung.ac.idSumarno Ismailsumarnoismail@ung.ac.idNurwan Nurwannurwan@ung.ac.idFebriani Takifbryanitaki@gmail.comThe economic model which deals with the economic cycle is Goodwin's Model. It presents the relationship between the employment rate and wage shares. In this study, the modification model was made, taking into three types of workers, namely high, medium, and low-skilled workers. Studies of the model are conducted by determining the equilibrium point and its stability analysis. Furthermore, a numerical simulation is given to see which model satisfies the ideal of Goodwin‘s model cycle prediction by using Indonesian data from 2000 to 2020. In the end, an investigation into the effects of reducing the wage gap between the three types of workers was conducted. The results showed two equilibrium points, namely The Equilibrium Point without Employment Rate and The Wages Share (T1) and the Existence Equilibrium Point of Employment Rate and Wages Share (T2). T1 achieves a stable node condition when ScQ<d+pi+et while T2 reaches a stable center condition when ScQ>d+pi+et. The simulation showed Goodwin's model of high- and low-skilled workers produced the ideal of Goodwin model cycle predictions, whereas Goodwin's model of medium-skilled workers and the entire economy (capitalist) didn’t produce the ideal of Goodwin model cycle predictions. Eventually, the effects of reducing the wage gap make the economy unstable.2022-03-11T01:42:46+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13462A Left-Symmetric Structure on The Semi-Direct Sum Real Frobenius Lie Algebra of Dimension 82022-03-11T01:48:34+07:00Edi Kurniadiedi.kurniadi@unpad.ac.idNurul Gusrianinurul.gusriani@unpad.ac.idBetty Subartinibetty.subartini@unpad.ac.id<p class="1ABSTRAK">Let be the Lie algebra of the semi-direct sum of the real vector space and the Lie algebra of the sets of all real matrices. In this paper, a Frobenius functional is constructed in order for the Lie algebra to be the real Frobenius Lie algebra of dimension 8. Moreover, a bilinear form corresponding to this Frobenius functional is symplectic. Then the obtained symplectic bilinear form induces the left-symmetric algebra structures on . In other words, the Lie algebra is the left-symmetric algebra. In particular, we give the formulas of its left-symmetric algebra structure explicitely. The left-symmetric algebra structures for case of higher dimension of this Lie algebra type are still an open problem to be investigated.</p>2022-03-11T01:42:47+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13701Forecasting Rice Paddy Production in Aceh Using ARIMA and Exponential Smoothing Models2022-03-11T01:48:34+07:00Nurviana Nurviananurviana@unsam.ac.idAmelia Ameliaameliamat@unsam.ac.idRiezky Purnama Sari Riezky Purnama Saririezkypurnamasari@unsam.ac.idUlya Nabilla Ulya Nabillaulya.nabilla@unsam.ac.idTaufan Talibtaufan.talib@fkip.unpatti.ac.id<p>Indonesia targets Aceh to be one of the paddy production centers and be able to carry out self-sufficient production in paddy and become a national granary. However, in reality, Aceh's paddy production in its province is not consistent from year to year. This province has not been able to meet the food needs of paddy independently, so that it supplies paddy from other regions due to the difficulty of detecting the presence of a surplus of paddy. The purpose of this research is to estimate the results of paddy production in Aceh for the future. The mathematical model that can be used is a time series model namely Autoregressive Integrated Moving Average (ARIMA) and Exponential Smoothing. The results of the estimation of paddy production in the next 5 years using the ARIMA (1,1,3) model are 2000616; 2017549; 1903585; 1944499; and 1929810. While the estimation results using the Winter Exponential Smoothing model are 1625925; 1645196; 1687667; 1605530; and 1555213. ARIMA model (1,1,3) produces an MSE/MAD value of , while the Winter Exponential Smoothing model produces an MSE/MAD value of . Therefore, it can be concluded that the Winter Exponential Smoothing model.</p>2022-03-11T01:42:47+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/14003Multipolar Intuitionistic Fuzzy Ideal in B-Algebras2022-03-11T01:48:34+07:00Royyan Amigoamigo.royyan@yahoo.comNoor Hidayatnoorh61@gmail.comVira Hari Krisnawativirahari@ub.ac.idIn this paper, we study with the definition of B-algebras, commutative B-algebras and fuzzy ideal in B-algebras. We consider the terminology of multipolar intuitionistic fuzzy ideal. We propose about multipolar intuitionistic fuzzy ideal in B-algebras and some related properties. Then, we discuss about theorems and propositions which contain some conditions for a multipolar intuitionistic fuzzy set become a multipolar intuitionistic fuzzy ideal in B-algebras.2022-03-11T01:42:48+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/14136Hybrid Model of Singular Spectrum Analysis and ARIMA for Seasonal Time Series Data2022-03-11T01:48:34+07:00Gumgum Darmawangumgum.darmawan@gmail.ugm.ac.idDedi Rosadidedirosadi@gadjahmada.eduBudi N Ruchjanabudi.nurani@unpad.ac.id<div><p class="Keywords">Hybrid models between Singular Spectrum Analysis (SSA) and Autoregressive Integrated Moving Average (ARIMA) have been developed by several researchers. In the SSA-ARIMA hybrid model, SSA is used in the decomposition and reconstruction process, while forecasting is done through the ARIMA model. In this paper, hybrid SSA-ARIMA uses two auto grouping models. The first model, namely the Alexandrov method and the second method, is alternative auto grouping with a long memory approach. The two-hybrid models were tested for two types of seasonal patterns, multiplicative and additive seasonal time series data. The analysis results using both methods give accurate results; as seen from the MAPE generated the 12 observations for the future, the value is below 5%. The hybrid SSA-ARIMA method with Alexandrov auto grouping is more accurate for an additive seasonal pattern, but the hybrid SSA-ARIMA with alternative auto grouping is more accurate for a multiplicative seasonal pattern.</p></div>2022-03-11T01:42:48+07:00Copyright (c) 2022 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/14407Elliptical Orbits Mode Application for Approximation of Fuel Volume Change2022-03-11T01:48:35+07:00Jovian Dian Pratamajoviandianpratama@yahoo.comRatna Herdianaherdiana.math@gmail.comSusilo Hariyantosus2_hariyanto@yahoo.com<p class="Abstract">This article discusses the Elliptical Orbits Mode (EOM) as a method of approximating the function of changing the volume of fuel in the Underground Yank (UT). This research was conducted at the 45.507.21 Candirejo Tuntang Pertamina Gas Station. The calculation of the approximation method will be applied to the measuring book data from the Semarang Metrology Regency specifically for the Pertalite (Fuel Product of Pertamina) buried tank, because the calculation of the gas station is not smooth, it is necessary for a smoother data fitting by considering Residual Square Error (RSS) and Mean Square Error (MSE). The result of this research is the application of EOM(θ) measuring book with elliptical height control produces smaller RSS and MSE compared to using COM, EOM, Least Square degree two and three.</p>2022-03-11T01:42:49+07:00Copyright (c) 2022 CAUCHY