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Employee scheduling is an activity plan for time sharing that contains a schedule for carrying out planned activities in the form of a table. This study aims to create an employee schedule model using a Genetic Algorithm, which is a heuristic method inspired by the process of natural selection, the strong will survive and reproduce, the stages of the Genetic Algorithm are population initialization, fitness value, selection, crossover, and mutation. The study results show an optimal model consisting of at most two shifts with a maximum of two holidays a week and not consecutively.

This study constructs an SVIR-type COVID-19 spread model into a model with control variables or optimum control problems. In the formulation of the model with controls, we set four control variables, namely vaccination strategy, quarantine, reduction of vaccine shrinkage, and treatment. Pontryagin 's maximum principle is applied in the model as a sufficient condition to achieve optimum conditions for minimizing the objective function . This study uses a numerical solution to describe the theoretical results. The results showed that the control model could accelerate the decrease in the number of individuals in the infected population class. We found that vaccination is a top priority that needs to be done to reduce the number of cases of COVID-19 infection. In addition, the implementation of quarantine can also be considered to accelerate the decrease in the number of individuals infected with COVID-19.

The increasingly rapid development of the business world requires companies engaged in industry, trade, and services to continue to optimize their business activities to win the market competition. Mikaila Bakery is one of the businesses producing birthday cakes in Gorontalo Province. In the birthday cake business at Mikaila Bakery, so far, the amount of production is only determined by estimates, so profits do not reach optimal profits. This study aimed to determine the optimal profit obtained in the production of birthday cakes at Mikaila bakery using the branch and bound method and to determine the results of sensitivity analysis to changes in the objective function coefficients and constraint functions in the branch and bound method. The analysis results show that using the branch and bound method, Mikaila Bakery's cake shop gets an optimal profit of Rp. 38,433,000 per month or an increase of Rp. 3.4% of the previous profit. The results of the sensitivity analysis show that profits will remain in optimal conditions if the birthday cake business at Mikaila Bakery follows the changes that occur in the coefficient of the objective function and the constraint function based on the upper bound and lower bound according to the output. Which has been generated using POM-QM software.

In certain cases, the response variable has an excess zero that causes overdispersion. Therefore, to overcome overdispersion because excess zero Zero-inflated negative binomial regression can be used. The purpose of this study is to apply Zero inflated negative binomial regression to model the case of severe pneumonia in Bone Bolango and on the city of Gorontalo. Based on the result of ZINB Regression, it was found that there are 3 (three) factors that are significant that is ASI, Vitamin A, and low birth weight.

Math is applicable in many fields, including financial computing and discussing options. Options are contracts between two parties. The first part acts as a buyer with non-obligatory rights to buy or sell from the second party, who act as the seller with particular assets of predetermined time and price. This research aims to compare the monte Carlo-Antithetic Variate and monte Carlo-Control Variate in determining the purchase price of the Asian option. This study uses data from the closing price of the daily stock of PT Adhi Karya Tbk from October 1st, 2018 – to November 27th, 2019. The findings revealed varying option prices and different error standards. The Antithetic Variate simulation produces option price Rp. 246,6821 and error standard 0,071495 in 10000000th simulation and the Control Variate simulation produce option price Rp. 183,2139 and error standard 0,09716 in the 5000th simulation. The result was that the Control Variate was considered better at determining Asian option purchase price because of the smaller option and faster error standard in approaching zero.

This article discusses the survey research aims to find out the Correlation between self-regulated learning and students’ mathematics learning outcomes in the topic of trigonometry in SMA Negeri 1 Gorontalo. This study focuses on 32 eleventh-grade students in the site area during the academic year of 2018/2019. Moreover, a multiple-choice test was used to collect the data on mathematics learning outcomes, as well as a questionnaire to collect data on self-regulated learning. The hypothesis was tested using the regression and correlational analysis test. The result indicates that self-regulated learning positively correlates with students’ mathematics learning outcomes with the correlational and determination coefficient values of 0.6311 and 40%, respectively. In other words, such a learning model contributes 40% to mathematics learning outcomes; the remaining 60% is influenced by other factors excluded in this research.

Currently, the problem of environmental hygiene caused by the accumulation of garbage becomes a serious problem for every community. In addressing this problem, an efficient waste transport process is required. This study aims to find the shortest route of garbage transportation in Gorontalo city by using Floyd Warshall Algorithm by finding the smallest weight between each point (Vertex). In this study, the weights used in the Floyd Warshall Iteration Algorithm were Alternative weights obtained by the Multi-Attribute Decision-Making approach (MADM). The criteria for determining weights in MADM use three indicators that affect the efficiency of garbage transportation, namely Distance, time, and congestion. The route used in this study is the dump truck route with 17 garbage transportation points. After obtaining the Alternate weight and iteration using Floyd Warshall algorithm obtained the shortest route with the smallest trajectory weight of 110.845.

Achmad DS, Gani S, Ardiansyah W, Mokoginta MM, Nurdin MS, Jompa J, Indrianti MA, Achmad N. 2022. Population dynamics of reef fish in the Kwandang Bay, Sulawesi Sea, Indonesia. Biodiversitas 23: 5217-5226. The grouper stocks in Kwandang Bay, Sulawesi Sea, Indonesia, are dominated by orange-spotted grouper (Epinephelus coioides) and coral trout (Plectropomus leopardus). However, the Kwandang Bay grouper fishery is currently experiencing serious challenges due to population decline resulting in a decline in both the average size of fish caught and the production volume. This study was conducted in Kwandang Bay, Sulawesi Sea, from January to December 2021. The population dynamics parameters estimated were growth, recruitment, mortality, exploitation rate and yield per recruit. The results showed that the total length (TL) of E. coioides and P. leopardus ranged from 16.50-101 cm and 17.90-60 cm, respectively, with Von Bertalanffy K-coefficients of 0.38 and 0.69, respectively. Recruitment occurred during most of the year, with respective recruitment value ranges of 0.99-17.11% and 0.08-19.22%. Natural and fishing mortality was 0.69/year-1 and 0.87/year-1 for E. coioides, 1.16/year-1 and 1.47/year-1 for P. leopardus. Beverton and Holt yield per recruit analysis indicated recruitment overfishing of both E. coioides and P. leopardus. Fishing regulations are needed to maintain a sustainable grouper fishery, including a 25% reduction in fishing vessels and gear, to enable the groupers of Kwandang Bay to spawn at least once during their life cycle.

This study aims to describe the difficulties of online learning in mathematics subjects in the midst of the Covid-19 pandemic. This research is a descriptive research with a quantitative approach. The subjects in this study were students of class VIII 3 and VIII 4 at SMP Negeri 4 Gorontalo. Data collection was obtained from data from questionnaires and student interviews. To see student responses in online learning on mathematics subjects in the midst of the Covid-19 pandemic, a questionnaire was given with indicators, namely: (1) Difficulty in accessing the internet network and operating online media during learning, and (2) Difficulty in understanding objects, facts, concepts, principles and mathematical operations. Based on the data obtained from 61 students, there were 8 students in the high category, 41 students in the moderate category and 12 students in the low category. This means that the difficulty level of online learning in mathematics subjects in the midst of the Covid-19 pandemic in class VIII of SMP Negeri 4 Gorontalo is in the Medium category.

This research was conducted with the aim of knowing the quality of teacher-made tests, this study was conducted at SMP Negeri 4 Gorontalo in the 2020/2021 school year. Subjects in the study in the form of odd semester final exam tests of mathematics subjects given to students along with the answers/responses of students to the tests given. The student in question is a class VIII student with a total of 266 students. The quality of the teacher's math tests is analyzed based on the difficulty level, differentiating power, and function of the extractor. The results showed that the quality of mathematics tests made by teachers in State Junior High School 4 Gorontalo as many as 25 items with objective forms can be categorized as less good. This is indicated by the three indicators used to fall into the category of less good.

This study was aimed at discussing survival analysis in Pulmonary Tuberculosis patients in Aloei Saboe using Weibull regression to find out the factors that influence the patient’s recovery rate. To analyze the survival time, the Kaplan-Meier curve is used then the process continues into Log-Rank Test to see the differences between groups in a curve. Weibull Regression is used to determine the significant factors based on a log-rank test in the rate of recovery of Pulmonary Tuberculosis patients. The results of the study concluded age, shortness of breath, fever, cough, history of illness and smoking habits are factors that significantly influence the rate of recovery of Pulmonary Tuberculosis patients.

Penelitian ini bertujuan untuk mendeskripsikan Penggunaan media e-learning dalam pembelajaran matematika di masa pandemi (Covid-19). Penelitian ini adalah penelitian deskriptif kuantitatif dengan populasi seluruh peserta didik kelas IX SMP N 4 Kota Gorontalo yang berjumlah 217 peserta didik. Sampel dalam penelitian sebanyak 22 orang. Teknik pengambilan sampel yaitu simple random sampling. Data penelitian diperoleh dari lembar pengamatan guru dan peserta didik terkait penggunaan media e-learning ( Zoom, Whatsapp, Google Classroom), tes hasil belajar angket respon peserta didik serta wawancara guru dan peserta didik tentang penggunaan media e-learning dalam pembelajaran matematika di masa pandemi. Hasil penelitian menunjukan bahwa penggunaan media e-learning dalam pembelajaran matematika di masa pandemi berada pada kategori kurang baik yang ditunjukan dengan Kegiatan Guru memperoleh rata-rata presentase 54,4%, kegiatan Peserta didik memperoleh rata-rata 60%, respon peserta didik memperoleh rata-rata 73,6%, dan tes hasil belajar presentase peserta didik yang tuntas adalah 45.4% dan peserta didik yang tidak tuntas sebesar 54,5%.

This study discusses the spread of measles in a mathematical model. Mathematical modeling is not only limited to the world of mathematics but can also be applied in the health sector. Measles is a disease with a high transmission rate. The spread of measles in this model was modified by adding the treated population and the treatment parameters of the exposed population. In this article, we examine the equilibrium points in the SMEIUR mathematical model and perform stability analysis and numerical simulations. In this study, two equilibrium points were obtained, namely the disease-free and endemic equilibrium point. After getting the equilibrium point, an analysis is carried out to find the stability of the model. Furthermore, the simulation produces a stable disease-free equilibrium point at conditions R01 and a stable endemic equilibrium point at conditions R01. In this study, a numerical simulation was carried out to see population dynamics by varying the parameter values. The simulation results show that to reduce the spread of measles, it is necessary to increase the rate of advanced immunization, the rate of the infected population undergoing treatment, and the proportion of individuals who are treated cured.

Penelitian ini membahas tentang model diskrit eko-epidemiologi. Model eko-epidemiologi adalah gabungan dari ilmu ekologi dan epidemiologi yang membahas tentang interaksi antara predator, prey rentan, dan prey terinfeksi menggunakan fungsi respon Holling tipe I dan pertumbuhan prey rentan mengunakan fungsi logistik untuk membatasi pertumbuhan yang berlebihan pada prey rentan.Model diskrit eko-epidemiologi diperoleh dengan mendiskritisasikan model eko-epidemiologi menggunakan metode Euler. Dari model diskrit tersebut diperoleh 5 titik kesetimbangan, yaitu titik kesetimbangan E0 dimana semua populasi mengalami kepunahan, titik kesetimbangan E1 ketika terjadi kepunahan pada populasi prey terinfeksi dan predator, titik kesetimbangan E2 ketika terjadi kepunahan pada populasi prey terinfeksi, titik kesetimbangan E3 ketika terjadi kepunahan pada populasi predator, dan titik kesetimbangan E4 ketika semua populasi hidup berdampingan. Berdasarkan hasil analisisnya, selalu tidak stabil, hal ini disebabkan oleh nilai eigen yang diperoleh pada persamaan linierisasi model di sekitar titik-titik ekuilibrium tersebut, nilai mutlaknya selalu besar satu. Untuk E1, E2, E3, dan E4 kestabilan titik-titik kesetimbanganditentukan oleh suatau syarat dan kondisi tertentu.

This research discussed the SEIPR mathematical model on the spread of pneumonia among children under five years old. The development of the model was done by considering factors of immunization and treatment factors, in an effort to reduce the rate of spread of pneumonia. In this research, mathematical model construction, stability analysis, and numerical simulation were carried out to see the dynamics of pneumonia cases in the population. The model analysis produces two equilibrium points, which are the equilibrium point without the disease, the endemic equilibrium point, and the basic reproduction number ( ) as the threshold value for disease spread. The point of equilibrium without disease reaches a stable state at the moment , which indicates that pneumonia will disappear from the population, while the endemic equilibrium point reaches a stable state at that time , which indicates that the disease will spread in the population. Furthermore, numerical simulations show that increasing the rate parameters of infected individuals undergoing treatment ( ), the treatment success rate ( ), and the immunization proportion ( ), could suppress the basic reproductive number so that control of the disease spread rate can be accelerated.

This study aims to describe students' mathematics learning outcomes through online learning for the 2019/2020 academic year on the subject of flat-sided space geometry. This descriptive study was conducted at SMP Negeri 5 Paguyaman involving 28 students of class VIII as a sample selected using the purposive sampling technique. Data collection techniques in this study were tests in the form of multiple-choice questions and student response questionnaires. The results of the research that refer to the cognitive domain of the revised Bloom taxonomy by Anderson and Krathwohl show that the C1 cognitive domain is remembering, the ability of students to remember, recognize or know a concept of the material being asked in the questions given an average of 77.36% is in a good category. C2 cognitive domain is understanding; students' ability to understand the material on average 35.75% is in the poor category. C3 cognitive realm applies, on this indicator, students' ability to apply the formula to the questions given an average of 17.85% is in the poor category. C4 cognitive domain analyzes students' ability to analyze the average question is 39.70% who are in the poor category. With the average percentage of all cognitive domains, namely 45.71%, students' mathematics learning outcomes through online learning on the subject of flat-side space geometry is still in the low category, and learning using Facebook Messenger has not provided maximum results.

This article discusses about mathematical model of Limboto lake silting with water hyacinth cleaning solution. Modelling begins with constructing a model based on the factors that affect silting which is then formed into a system of first order differential equations. Furthermore, the model is analyzed by looking for equilibrium and stability. To see the condition of lake silting based on the stability condition, a numerical simulation was performed. The simulation results show that with water hyacinth cleaning, the lake will maintain its existence, which is indicated by an increase the Limboto lake volume, although there is still a decrease in volume due to the presence of sediment and nutrients from the river.

This paper discusses the mathematical model of drug users with education. Optimal control theory was used on this model with education as a control to achieve the goal of minimizing the number of drug users. The optimal control problem was analyzed using Pontryagin’s minimum principle and performed numerical simulation by using a 4th-order Runge-Kutta method. Based on the numerical simulation, there was a change in the number in each population which caused the population with education to increase, and control with education resulted in the reduced number of drug users. Keywords: Optimal control; mathematical model; drug users; education ABSTRAK Artikel ini membahas tentang model matematika penyebaran pengguna narkoba dengan faktor edukasi. Teori kontrol optimal diterapkan pada model ini dengan pemberian kontrol berupa edukasi dengan tujuan untuk meminimumkan jumlah pengguna narkoba. Kontrol optimal dianalisis menggunakan Prinsip Minimum Pontryagin dan dilakukan simulasi numerik dengan menggunakan metode Runge-Kutta orde 4. Berdasarkan simulasi diperoleh bahwa terjadi perubahan jumlah di tiap populasi dan mengakibatkan jumlah populasi dengan edukasi bertambah, serta pemberian kontrol dengan edukasi mengakibatkan jumlah pengguna narkoba berkurang. Kata kunci : Kontrol optimal; model matematika; pengguna narkoba; edukasi

Limboto lake is one of assets of Province of Gorontalo that provides many benefits to the surrounding society. The main problem of Limboto lake is the silting of the lake due to sedimentation caused by forest erosion, household waste, water hyacinth, and fish farming which is not environmentally friendly. In this article, a mathematical approach is used to modeling the Limboto lake siltation by including the revitalization solution namely the lake dredging. Mathematical modeling begins by building and limiting assumptions, constructing variables and parameters in mathematical symbols, and forming them into a first order differential equation system deterministically. Furthermore, we study the dynamics of the model such as identifying the existence of equilibrium points and their stability conditions. We also give a numerical simulations to show the conditions based on the stability requirements in previous analytical results.

As a form of purchased goods from other state’s imports have impacts both positive and negative to the states’s condition; therefore, prediction is required. Employing Autoregressive Integrated Moving Average (ARIMA) and Holt’s Double Exponential Smoothing (DES) methods, this study intends to identify which of the methods is the most accurate to predict Indonesia’s import value. The ARIMA method stage involved: data ploting, data stasioneriation, temporary model identification, parameter estimation, test residual assumption, and prediction. Moreover, the Holt’s DES method involved: data plotting, initial value determination, optimal parameter identification, Level Lt and Trend Tt value quantification, andprediction. The result shows that ARIMA method is the most accurate method to predict Indonesia’s import value.

Melalui tahapan pengembangan model ADDIE peneliti merancang suatu media pembelajaran menggunakan software Articulate Storyline pada materi Statistika dan Peluang. Kelayakan media dilihat oleh dua aspek yaitu aspek kevalidan dan kepraktisan. Hasil analisis menunjukkan validasi ahli media dan ahli materi memperoleh rata-rata persentase berturut-turut 86,25% dan 92,27% yang dikategorikan “sangat valid”. Selanjutnya dari hasil uji coba diperoleh respon positif dari guru dan siswa dengan rata-rata persentase sebesar 79,35% dan 93,20% yang dikategorikan “praktis dan sangat praktis”. Rata-rata persentase untuk kedua aspek ini sebesar 87,77% yakni kategori sangat efektif, sehingga media pembelajaran matematika ini layak untuk diimplementasikan di kelas.

In this paper, the influence of additive Allee effect in prey and periodic harvesting in predator to the dynamics of the Leslie-Gower predator-prey model is proposed. We first simplify the model to the non-dimensional system by scaling the variable and transform the model into an autonomous system. If the effect Allee is weak, we have at most two equilibrium points, else if the Allee effect is strong, at most four equilibrium points may exist. Furthermore, the behavior of the system around equilibrium points is investigated. In the end, we give numerical simulations to support theoretical results.

The present work discusses a mathematical model of diphtheria transmission. Diphtheria is an infection of the throat and upper respiratory tract that is caused by bacteria called corynebacterium. The model was developed by adding latent population and death parameter resulted from this infection. The purpose of this study was to construct a mathematical model, analyze the stability of the equilibrium point, and interpret the simulation of the SEIQR mathematical model in the trasnsmission of diphteria. From the constructed model, there were bacis reproduction number () and two equilibrium points, namely disease-free and endemic equilibrium point would be stable if and , respectively. Moreover, a nunerical simulation was carried out to determine the dynamics of the diphteria transmission. The simulation results showed that if the rates of vaccinated propotion and individual are increased, the infaction woud grandually go away from the population. In short, diphteria transmission be prevented by increasing the rate of vaccnation.Keywords: Basic reproduction number, Diphtheria, Equilibrium point, Mathematical model, Numerical simulationMSC2020: 37A99, 37A10, 37C10

Penelitian ini membahas tentang model predator-prey dengan asumsi pemberian racun pada predator. Interaksi antara predator-prey menggunakan fungsi respons Holling tipe II. Pertumbuhan predator-prey menggunakan fungsi logistik. Dinamika model di sekitar titik kesetimbangan dipengaruhi oleh kestabilan dari titik kesetimbangan. Dari model tersebut diperoleh dua titik kesetimbangan model, yaitu titik kesetimbangan kepunahan predator dan titik kesetimbangan interior. Titik kesetimbangan kepunahan pada predator selalu tidak stabil dalam kondisi apapun, sedangkan titik kesetimbangan interior dapat mencapai kondisi stabil dengan beberapa syarat. Pada bagian akhir, diberikan simulasi numerik untuk menunjukkan parameter efektivitas pemberian racun pada predator.

Penjadwalan karyawan termasuk masalah yang sering dihadapi pada suatu perusahaan. Makalah ini membahas tentang masalah penjadwalan karyawan menggunakan Integer Linear Programming (ILP) dengan fungsi objektif linear, fungsi kendala linear, dan variabel berupa bilangan bulat. Data pnelitian diperoleh dari data primer suatu perusahaan yg terdiri dari jumlah karyawan, jumlah jenis karyawan, dan pembagian shift kerja. Hasil yang diperoleh berupa jadwal karyawan yang menunjukkan efisiensi waktu dan biaya. Capaian ini diperoleh tanpa melewati batas waktu yang ditetapkan dan meminimumkan biaya pengeluaran.