http://ejournal.uin-malang.ac.id/index.php/Math/issue/feedCAUCHY2021-11-12T09:02:18+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, <strong>but are not limited</strong> <strong>to</strong>, 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/13954Front-Matter2021-11-12T08:18:43+07:00Front Mattercauchy@uin-malang.ac.id2021-11-12T08:11:41+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13955Back-Matter2021-11-12T08:18:44+07:00Back Mattercauchy@uin-malang.ac.id2021-11-12T08:11:42+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/10337Genetic Algorithm for Variable Selection and Parameter Optimization in SVM and Fuzzy SVM for Colon Cancer Microarray Classification2021-11-12T08:18:44+07:00Irhamah Irhamahirhamah@statistika.its.ac.idElok Faiqahelokfaiqoh212@gmail.comHeri Kuswantoheri_k@statistika.its.ac.idNLP Satyaning Pradnya Paramitasat.pradnyaparamita@gmail.comColon cancer is the second leading cause of cancer-related deaths in the world, hence research on that topic needs to be undertaken with improvement. Recent advanced in microarray technology allows the monitoring of the expression level of a large set of genes simultaneously. Microarray data is a type of high-dimensional data with hundreds or even thousands number of genes (features), while usually the number of patients observed (observations) is much smaller than the number of features. This study uses a colon cancer microarray dataset contains two class of genes, normal and tumor. The aims of this study is to develop a classification model using fuzzy support vector machines (FSVM) hybridized with genetic algorithm (GA) for classifying individuals based on gene expression. Fuzzy memberships was used in SVM in order to deal with the case of imbalanced microarray data. Meanwhile, the role of genetic algorithm is, firstly, to select the relevant genes as the features and, secondly, to optimize the parameter of FSVM as GA is able to handle the problem of nonlinear optimization that has a high dimension, adaptable, and easily combined with other methods. The classification using FCBF selection has a higher accuracy value than the ones without the selection. The results also show that FSVM that has been optimized using GA has the highest accuracy value compared to other classification methods used in this study.2021-11-12T08:11:43+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/11575A Combination of Generalized Linear Mixed Model and LASSO Methods for Estimating Number of Patients Covid 19 in the Intensive Care Units2021-11-12T08:18:44+07:00Alona Dwinataalonadwinata@umrah.ac.idKhairil Anwar Notodiputrokhairil@apps.ipb.ac.idBagus Sartonobagusco@apps.ipb.ac.idGeneralized linear mixed models (GLMM) combined with the L<sub>1</sub> penalty (Least Absolute Shrinkage and Selection Operator/LASSO) is called LASSO GLMM. LASSO GLMM reduces overfitting and selects predictor variables in modeling. The aim of this study is to evaluate the model's performance for predicting Covid-19 patients with certain congenital disease that require ICU based on the results of blood tests laboratory and patient’s vital signs. This study used binary response variables, 1 if the patient was admitted to the ICU and 0 if the patient was not admitted to the ICU. The fixed effect predictor variables are the results of blood tests laboratory and patient’s vital signs. The random effect predictor variable is patient's congenital disease. The result showed that the average of accuracy and AUC from LASSO GLMM is more than the average of accuracy and AUC from LASSO GLM by using 5% level of significance. Respiratory rate and Lactate show a significance effect to predict the ICU needs of Covid-19 patients. The random effects patient's congenital disease has significance effect at 5% level of significance. It means that the ICU needs for Covid-19 patients varies among patient's congenital disease. We can conclude that GLMM LASSO with the random effect of patient’s congenital diseases has better modeling performance to predict the ICU needs of Covid-19 patients based on the results of blood tests laboratory and patient’s vital signs. The results of this modeling can quickly detect Covid-19 patients who need the ICU and can help medical staff use ICU resources optimally2021-11-12T08:11:52+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12141Inclusion Properties of The Homogeneous Herz-Morrey Spaces With Variable Exponent2021-11-12T08:18:44+07:00Hairur Rahmanhairur@mat.uin-malang.ac.idIn this paper, we have discussed about the inclusion properties of the homogeneous Herz-Morrey spaces with variable exponent and the weak homogeneous spaces with variable exponent. We also studied the inclusion relation between those spaces.2021-11-12T08:11:54+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12488Sentiment Analysis on Government Performance in Tourism During The COVID-19 Pandemic Period With Lexicon Based2021-11-12T08:18:45+07:00Adri Priadanaadripriadana3202@gmail.comAhmad Ashril Rizalashril.rizal@gmail.comThe COVID-19 pandemic impact has affected all industries in Indonesia and even the world, including the tourism industry. Researchers have a role in researching to answer the needs of the tourism industry, especially in making tourism and business destination management programs and carrying out activities oriented to meet the needs of the tourism industry. Meanwhile, the government has a role in making policies, especially in the roadmap, for developing the tourism industry. This study aims to track trending topics in social media Instagram since COVID-19 hit. The results of trending topics will be classified by sentiment analysis using a Lexicon-based and Naive Bayes Classifier. Based on Instagram data taken since January 2020, it shows the five highest topics in the tourism sector, namely health protocols, hotels, homes, streets, and beaches. Of the five topics, sentiment analysis was carried out with the Lexicon-based and Naive Bayes classifier, showing that beaches get an incredibly positive sentiment, namely 80.87%, and hotels provide the highest negative sentiment 57.89%. The accuracy of the Confusion matrix's sentiment results shows that the accuracy, precision, and recall are 82.53%, 86.99%, and 83.43%, respectively.2021-11-12T08:11:56+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12634Optimal Prevention and Treatment Control on SVEIR Type Model Spread of COVID-192021-11-12T08:18:45+07:00Jonner Nainggolanjonner2766@gmail.com<p>COVID-19 pandemic has disrupted the world's health and economy and has resulted in many deaths since the first case occurred in China at the end of 2019. Moreover, The COVID-19 disease spread throughout the world, including Indonesia on March 2, 2020. Coronavirus quickly spreads through droplets of phlegm through the throat to the lungs. Researchers in the medical field and the exact science are jointly examined the spread, prevention, and optimal control of COVID-19 disease. Due to the prevention of COVID-19, a vaccine has been found in early 2021, which at the time, the vaccination process was carried out worldwide against COVID-19. This paper examines the spread model of SVEIR-type COVID-19 by considering the vaccination subpopulation. In this study, control of prevention efforts ( and ) and healing efforts are given and being analyzed with the fourth-order Runge-Kutta approach. Based on numerical simulations, it can be seen that using the controls and can reduce the number of infected individuals in the subpopulation compared to those without control. The control can increase the number of recovered individual subpopulations.</p><div><p class="Keywords"><strong>Keywords</strong>: COVID-19; <em>SVEIR</em> model; optimal control; treatment; vaccination.</p></div>2021-11-12T08:11:57+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12772Analysis of Landing Airplane Queue Systems at Juanda International Airport Surabaya2021-11-12T08:18:45+07:00Yuniar Faridayuniar_farida@uinsby.ac.idFadilah Akbarfadilakbar783@gmail.comMoh. Hafiyusholehhafiyusholeh@gmail.comMoh. Hartonomoh.hartono@polinema.ac.id<p class="Abstract"><span lang="EN-US">Juanda International Airport is currently preparing to realize the construction of terminal 3. This construction project impression that Juanda Airport is experiencing an overload, including in the airplane queue. This study aims to analyze the current queuing system at the Juanda International Airport apron, whether effective, quite effective, or less effective in serving the number of existing flights with two terminals. An analysis of the queuing system was conducted in several scenarios. They are in normal/regular condition, a scenario if there is an increase in flight frequency, and a scenario if there is a reduction in aprons’ number because of certain exceptional situations. To analyze the airplane’s landing queue at Juanda airport apron, the queuing model (M/M/51) : (FCFS/∞/∞) is used. From this model, the results show that in normal conditions, the estimated waiting time for each airplane in the system is 0.18 hours with a queue of 2 up to 3 planes/hour, categorized as effective. In one apron reduction scenario, each airplane’s estimated waiting time in the system is 0.7 hours, with a queue of 6 up to 7 planes categorized as less effective. In the scenario of additional flights, only 9 other flights are allowed every day to keep the service performance still quite effective. By obtaining this results analysis, the decision of PT. Angkasa Pura 1 (Persero) to build terminal 3 is suitable to reduce queuing time and improve Juanda International Airport services to be more effective.</span></p>2021-11-12T08:12:00+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12796On Rainbow Vertex Antimagic Coloring of Graphs: A New Notion2021-11-12T08:18:45+07:00Marsidi Marsidimarsidiarin@gmail.comIka Hesti Agustinikahesti.fmipa@unej.ac.idDafik Dafikikahesti.fmipa@unej.ac.idElsa Yuli Kurniawatielsayuli@unej.ac.id<p>All graph in this paper are simple, finite, and connected. Let be a labeling of a graph . The function is called antimagic rainbow edge labeling if for any two vertices and , all internal vertices in path have different weight, where the weight of vertex is the sum of its incident edges label. The vertex weight denoted by for every . If G has a antimagic rainbow edge labeling, then is a antimagic rainbow vertex connection, where the every vertex is assigned with the color . The antimagic rainbow vertex connection number of , denoted by , is the minimum colors taken over all rainbow vertex connection induced by antimagic rainbow edge labeling of . In this paper, we determined the exact value of the antimagic rainbow vertex connection number of path ( ), wheel ( ), friendship ( ), and fan ( ).</p>2021-11-12T08:12:02+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12848The Confidence Interval of the Estimator of the Periodic Intensity Function in the Presence of Power Function Trend on the Nonhomogeneous Poisson Process2021-11-12T08:18:45+07:00Ikhsan Maulidiikhsanmaulidi@rocketmail.comBonno Andri Wibowobonno1818@gmail.comNina Valentikadosen02339@unpam.ac.idMuhammad Syazalimuhamad.syazali@idu.ac.idVina Aprilianivina.apriliani@ar-raniry.ac.id<p class="Abstract">The nonhomogeneous Poisson process is one of the most widely applied stochastic processes. In this article, we provide a confidence interval of the intensity estimator in the presence of a periodic multiplied by trend power function. This estimator's confidence interval is an application of the formulation of the estimator asymptotic distribution that has been given in previous studies. In addition, constructive proof of the convergent in probability has been provided for all power functions.</p>2021-11-12T08:12:04+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12934On the Modification of Newton-Secant Method in Solving Nonlinear Equations for Multiple Zeros of Trigonometric Function2021-11-12T08:18:46+07:00Juhari Juharimuhammadroziqinlina@gmail.comThis study discusses the analysis of the modification of Newton-Secant method and solving nonlinear equations having a multiplicity of by using a modified Newton-Secant method. A nonlinear equation that has a multiplicity is an equation that has more than one root. The first step is to analyze the modification of the Newton-Secant method, namely to construct a mathematical model of the Newton-Secant method using the concept of the Newton method and the concept of the Secant method. The second step is to construct a modified mathematical model of the Newton-Secant method by adding the parameter . After obtaining the modified formula for the Newton-Secant method, then applying the method to solve a nonlinear equations that have a multiplicity . In this case, it is applied to the nonlinear equation which has a multiplicity of . The solution is done by selecting two different initial values, namely and . Furthermore, to determine the effectivity of this method, the researcher compared the result with the Newton-Raphson method, the Secant method, and the Newton-Secant method that has not been modified. The obtained results from the analysis of modification of Newton-Secant method is an iteration formula of the modified Newton-Secant method. And for the result of using a modified Newton-Secant method with two different initial values, the root of is obtained approximately, namely with less than iterations. whereas when using the Newton-Raphson method, the Secant method, and the Newton-Secant method, the root is also approximated, namely with more than iterations. Based on the problem to find the root of the nonlinear equation it can be concluded that the modified Newton-Secant method is more effective than the Newton-Raphson method, the Secant method, and the Newton-Secant method that has not been modified2021-11-12T08:12:05+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12944Supplier Selection Analysis Using Minmax Multi Choice Goal Programming Model2021-11-12T08:18:46+07:00Novi Rustiana Dewinovirustiana@unsri.ac.idEka Susantieka_susanti@mipa.unsri.ac.idBambang Suprihatinbambangs@unsri.ac.idEndro Setyo Cahyonoendrosetyo_c@yahoo.co.idAnggun Permatabambangs@unsri.ac.idNurul Fadhila Yanitabambangs@unsri.ac.id<p class="AbstractTitle">Production control, inventory and distribution is an important factor in trading activities. These three factors are discussed in a system called Supply Chain Management (SCM). Procurement of goods from a company or trading business related to suppliers. In some cases, there are several supplier that can be assessed by considering certain factors. In certain cases, the data from several factors that are considered are uncertainty, so the fuzzy approach can be used. The MINMAX Multi Choice Goal Programming model can be used to solve fuzzy supplier selection problems with linear membership function. It can be applied to selecting supplier of Brastagi Oranges. There are four suppliers, namely Jaya, Mako, Baros. Gina. There are three factor to consider, cost, quality and delivery. The decision maker select the best supplier for ordering 17000 kg Brastagi oranges. The results, the best supplier is Gina with an order quantity of 10000 kg and Mako with a total order of 7000 kg</p>2021-11-12T08:12:06+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12993Spline Nonparametric Regression to Analyze Factors Affecting Gender Empowerment Measure (GEM) in East Java2021-11-12T08:18:46+07:00Luluk Mahfirohmahfirohluluk@gmail.comYuniar Faridayuniar_farida@uinsby.ac.id<p class="Abstract"><span lang="IN">Gender is a multidimensional issue that's </span><span lang="EN-US">not </span><span lang="IN">limited to gender discrimination</span><span lang="EN-US">, but also</span><span lang="EN-US">includes </span><span lang="IN">the economic, educational, and health aspects, </span><span lang="EN-US">which then </span><span lang="IN">become the focus of </span><span lang="EN-US">almost all the </span><span lang="IN">Sustainable Development Goals (SDGs). Evaluation of the development devoted to the perspective of the gender using several indicators, Gender Development Index (GDI) and Gender Empowerment Measure (GEM). GEM describes the role of women in the economic sphere and is measured by equality in political participation. GEM </span><span lang="EN-US">of </span><span lang="IN">East Java </span><span lang="EN-US">for 5 consecutive years (2014 – 2018)</span><span lang="IN"> is lower than the average national GEM. </span><span lang="EN-US">This study aims to identify factors affecting GEM in East Java </span><span lang="IN">using nonparametric regression spline quadratic. The result</span><span lang="EN-US"> of</span><span lang="IN">the regression model shows the factors affecting GEM East Java is the L</span><span lang="EN-US">abor </span><span lang="IN">F</span><span lang="EN-US">orce </span><span lang="IN">P</span><span lang="EN-US">articipation </span><span lang="IN">R</span><span lang="EN-US">ate</span><span lang="EN-US">(</span><span lang="IN">LFPR</span><span lang="EN-US">)</span><span lang="IN"> population of women (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image002.png" alt="" width="9" height="12" /></span><span lang="IN">), School Participation </span><span lang="EN-US">Rate</span><span lang="EN-US">(</span><span lang="IN">SPR</span><span lang="EN-US">)</span><span lang="IN"> high school population of women (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image004.png" alt="" width="10" height="12" /></span><span lang="IN">), Percentage of </span><span lang="EN-US">Population Female that</span><span lang="EN-US">W</span><span lang="IN">orking in the formal sector (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image006.png" alt="" width="10" height="12" /></span><span lang="IN">), sex ratio (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image008.png" alt="" width="10" height="12" /></span><span lang="IN">), Percentage of </span><span lang="EN-US">Population Female that Working as members of People’s Representative Council</span><span lang="IN"> (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image010.png" alt="" width="10" height="12" /></span><span lang="IN">), Percentage of </span><span lang="EN-US">Population Female that </span><span lang="IN">working as </span><span lang="EN-US">C</span><span lang="IN">ivil </span><span lang="EN-US">S</span><span lang="IN">ervants (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image012.png" alt="" width="10" height="12" /></span><span lang="IN">), and rate of women's income donations (</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image014.png" alt="" width="10" height="12" /></span><span lang="IN">). The model generates</span><span><img src="file:////Users/yuniar/Library/Group%20Containers/UBF8T346G9.Office/TemporaryItems/msohtmlclip/clip_image016.png" alt="" width="13" height="12" /></span><span lang="IN"> </span><span lang="EN-US">v</span><span lang="IN">alue of 93.74% and MAPE of 3.22%.</span><span lang="EN-US">This research contributes to the implementation of non-parametric spline regression in identifying various factors that influence social phenomena.</span></p>2021-11-12T08:12:09+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/12995Modeling Length of Hospital Stay for Patients With COVID-19 in West Sumatra Using Quantile Regression Approach2021-11-12T09:02:18+07:00Ferra Yanuarferrayanuar@yahoo.co.idAthifa Salsabila Devaathifasalsabila4300@gmail.comMaiyastri Maiyastrimaiyastri@sci.unand.ac.idHazmira Yozzahazmirayozza@sci.unand.ac.idAidinil Zetraaidinil@soc.unand.ac.id<p class="Abstract">This study aims to construct the model for the length of hospital stay for patients with COVID-19 using quantile regression and Bayesian quantile approaches. The quantile regression models the relationship at any point of the conditional distribution of the dependent variable on several independent variables. The Bayesian quantile regression combines the concept of quantile analysis into the Bayesian approach. In the Bayesian approach, the Asymmetric Laplace Distribution (ALD) distribution is used to form the likelihood function as the basis for formulating the posterior distribution. All 688 patients with COVID-19 treated in M. Djamil Hospital and Universitas Andalas Hospital in Padang City between March-July 2020 were used in this study. This study found that the Bayesian quantile regression method results in a smaller 95% confidence interval and higher value than the quantile regression method. It is concluded that the Bayesian quantile regression method tends to yield a better model than the quantile method. Based on the Bayesian quantile regression method, it investigates that the length of hospital stay for patients with COVID-19 in West Sumatra is significantly influenced by Age, Diagnoses status, and Discharge status.</p>2021-11-12T08:12:11+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13001The Ring Homomorphisms of Matrix Rings over Skew Generalized Power Series Rings2021-11-12T08:18:47+07:00Ahmad Faisolahmadfaisol@fmipa.unila.ac.idFitriani Fitrianifitriani.1984@fmipa.unila.ac.idLet M_n (R_1 [[S_1,≤_1,ω_1]]) and M_n (R_2 [[S_2,≤_2,ω_2]]) be a matrix rings over skew generalized power series rings, where R_1,R_2 are commutative rings with an identity element, (S_1,≤_1 ),(S_2,≤_2 ) are strictly ordered monoids, ω_1:S_1→End(R_1 ),〖 ω〗_2:S_2→End(R_2 ) are monoid homomorphisms. In this research, a mapping τ from M_n (R_1 [[S_1,≤_1,ω_1]]) to M_n (R_2 [[S_2,≤_2,ω_2]]) is defined by using a strictly ordered monoid homomorphism δ:(S_1,≤_1 )→(S_2,≤_2 ), and ring homomorphisms μ:R_1→R_2 and σ:R_1 [[S_1,≤_1,ω_1]]→R_2 [[S_2,≤_2,ω_2]]. Furthermore, it is proved that τ is a ring homomorphism, and also the sufficient conditions for τ to be a monomorphism, epimorphism, and isomorphism are given.2021-11-12T08:12:12+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13105Local Hölder Regularity of Weak Solutions for Singular Parabolic Systems of p-Laplacian Type2021-11-12T08:18:47+07:00Khoirunisa Khoirunisakhoir.n97@gmail.comCorina Karimco_mathub@ub.ac.idM. Muslikhmslk@ub.ac.id<p class="Abstract">In this paper, the Hölder regularity of weak solutions for singular parabolic systems of <em>p-</em>Laplacian type is investigated. By the Poincare inequality, we show that its weak solutions within Hölder space.</p>2021-11-12T08:12:13+07:00Copyright (c) 2021 CAUCHYhttp://ejournal.uin-malang.ac.id/index.php/Math/article/view/13642A Study of Count Regression Models for Mortality Rate2021-11-12T08:18:47+07:00Anwar Fitriantoanwarstat@gmail.comThis paper discusses how overdispersed count data to be fit. Poisson regression model, Negative Binomial 1 regression model (NEGBIN 1) and Negative Binomial regression 2 (NEGBIN 2) model were proposed to fit mortality rate data. The method used is comparing the values of Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) to find out which method suits the data the most. The results show that the data indeed display higher variability. Among the three models, the model preferred is NEGBIN 1 model.2021-11-12T08:12:14+07:00Copyright (c) 2021 CAUCHY