OJS UNPATTI Publication Center (Universitas Pattimura)
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MODELING GENDER DEVELOPMENT INDEX IN SOUTHEAST SULAWESI PROVINCE USING SEMIPARAMETRIC KERNEL REGRESSION
Full text linkThe issue of gender equality in Southeast Sulawesi still needs further attention, as indicated by the uneven value of the Gender Development Index (GDI) in each district/city in the region. Therefore, an in-depth analysis is needed to identify factors that affect the GDI. One method that can be used is semiparametric regression with the Nadaraya-Watson estimator, which allows modeling the relationship between variables with more flexibility. This study aims to build a semiparametric regression model to identify factors that contribute to HDI in Southeast Sulawesi Province. The results of the analysis showed that the optimal bandwidth values obtained were h1= 1.57, h2=0.49, h3=2.50 and h4=4.61. The resulting model has an R2 and MSE values of 99.8% and 0.14% respectively, indicating that the model has high accuracy in explaining the overall variation in GDI
ANALYSIS OF THREE SERVERS CLOSED SERIES QUEUING NETWORK WITH DELAY TIME USING MAX-PLUS ALGEBRA
Full text linkMax-Plus Algebra, which is the union of the set of all real numbers with an infinite singleton, equipped with maximum (max) and plus (+) operations, can be used to model and analyze algebraically the dynamics of a closed queuing network. This study aims to analyze the effect of delays in the start time of service activities on a closed series queuing network with three servers. This study is a study based on literature studies, mathematical model studies and simulations assisted by the Scilab computer program. The results show that the max-plus eigenvalue of a closed series queuing network with 3 servers, which is also the periodicity of network dynamics, is the largest service time of the server in the network. Delays in servers with the largest service time will continue to propagate for subsequent schedules. Delays in servers whose service time is not the maximum can still be tolerated, as long as the delay does not exceed the size of the element in the initial max-plus eigenvector, which corresponds to its largest service time. In this case, the system will be able to return to normal according to the original schedule, after undergoing a maximum of 4 stages of the service process since the beginning of the delay. Meanwhile, delays that exceed this will cause network scheduling to be late and will continue to spread to subsequent services
A MODEL ON MARKET EQUILIBRIUM USING A DIFFERENTIAL EQUATION WITH TIME DELAYS
Full text linkIn this paper, a model on market equilibrium is proposed using a delay differential equation with discrete delays as a modified version of the one proposed by Kobayashi (1996). The price of a commodity is determined using the equation involving weighted supply and demand functions. Both supply and demand functions are considered at the current time and sometimes in the past. The delays are chosen by considering the seasonal behavior of the market. We use data on some main commodities in Indonesia from 2018 to 2024 to validate the model. We found that the implementation of our modified Kobayashi model improves the estimation given by the original one. The implementation of the method also shows some characteristics of delay equations, that is longer delay time may include more dynamics, and more fluctuation, although that means it is more prone to instabilities. However, the problem of optimal delay time is yet to be resolved
MODELING THE IDX30 STOCK INDEX USING STEP FUNCTION INTERVENTION ANALYSIS
Full text linkThe significant decline in the IDX30 stock index occurred due to an intervention, namely the COVID-19 pandemic, which affected market stability and investment decisions. This study aims to model and forecast the IDX30 stock index using intervention analysis with a step function, which is very suitable for capturing long-term external shocks. The methodology used includes the ARIMA (AutoRegressive Integrated Moving Average) model combined with step function intervention analysis to account for structural changes due to external disturbances. The data used is sourced from investing.com, consisting of weekly IDX30 stock index prices from January 2019 to December 2023. The results show that the COVID-19 pandemic significantly impacted the IDX30 index, causing a drastic decline. The best model identified is ARIMA (1,2,1) with intervention parameters b = 0, s = 0, and r = 1. The forecasting results range from Rp. 488 to Rp. 505, with a Mean Absolute Percentage Error (MAPE) of 1.9404%, which shows the forecasting results are very good, indicating high forecasting accuracy. These findings highlight the effectiveness of intervention analysis in modeling financial time series data affected by external disturbances
A THREE-TERM CONJUGATE GRADIENT METHOD FOR LARGE-SCALE MINIMIZATION IN ARTIFICIAL NEURAL NETWORKS
Full text linkConjugate Gradient (CG) methods are widely used for solving unconstrained optimization problems due to their efficiency and low memory requirements. However, standard CG methods may not always guarantee sufficient descent condition, which can impact their robustness and convergence behavior. Additionally, their effectiveness in training artificial neural networks (ANNs) remains an area of interest. In response, this paper presents a three-term conjugate gradient (CG) method for unconstrained optimization problems. The new parameter is formulated so that the search direction satisfies the sufficient descent condition. The global convergence result of the new algorithm is discussed under suitable assumptions. To evaluate the performance of the new method we considered some standard test problems for unconstrained optimization and applied the proposed method to train different ANNs on some benchmark data sets contained in the NN toolbox. The experimental results show that performance is encouraging for both unconstrained minimization test problems and in training neural networks
IMPLEMENTASI MODEL PEMBELAJARAN PROBLEM SOLVING UNTUK MENINGKATKAN PENGUASAAN MATERI GERAK DAN GAYA
Full text linkModel Problem Solving adalah model pembelajaran yang memberi peluang peserta didik untuk memecahkan masalah yang diberikan secara mandiri sehingga mampu memperoleh konsep dan kemudian mampu menerapkan konsep yang telah diperolehnya untuk memecahkan masalah dalam bentuk lainnya. Penilitian ini bertujuan untuk mengetahui peningkatan penguasaan materi gerak dan gaya dalam pembelajaran IPA pada peserta didik kelas Vll SMP Negeri 22 Ambon yang diajarkan dengan menerapkan model pembelajaran Problem Solving. Tipe penilitian ini adalah one-Group Pretest-postest Design, dengan 19 peserta didik sebagai sampel penilitian yang diperoleh dengan menggunakan teknik acak (secara undi). Data penilitian ini dihimpun melalui instrument tes dan non tes, instrument tes berupa tes awal dan akhir, sedangkan instrumen non tes berupa Lembar Kerja Peserta Didik (LKPD). Hasil penilitian menujukkan penguasaan materi awal, 100% peserta didik berada pada kualifikasi gagal dengan rerata nilai adalah 29. Hasil analisis selama proses pembelajaran berlangsung menunjukan rerata skor pencapaian peserta didik 81,7 berada pada kualifikasi baik. Rerata skor pencapaian skor akhir peserta didik mencapai 81,8 dengan kualifikasi sangat baik. Untuk hasil Uji N-Gain diperoleh rerata skor peserta didik 0,74 berada pada kualifikasi tinggi. Dengan demikin dapat disimpulkan bahwa penerapan model pembelajaran Problem Sovling dapat meningkatkan penguasaan materi gerak dan gaya dalam pembelajaran IPA pada peserta didik kelas Vll SMP Negeri 22 Ambon
BILANGAN TERHUBUNG PELANGI LOKASI PADA GRAF KEMUDI DAN GRAF JARING
Full text linkKonsep bilangan terhubung pelangi lokasi pada graf merupakan salah satu inovasi dalam teori pewarnaan graf yang menggabungkan konsep pewarnaan titik pelangi dan dimensi partisi pada graf. Konsep ini bertujuan untuk menentukan bilangan bulat positif terkecil sehingga terdapat pewarnaan- pelangi lokasi pada graf yang memungkinkan setiap titik memiliki kode pelangi yang unik. Dalam penelitian ini, kami mengkaji bilangan terhubung pelangi lokasi pada graf kemudi dan graf jaring. Hasil dari kedua graf menunjukkan bahwa jumlah titik pemotong berbanding lurus dengan bilangan terhubung pelangi lokasi pada graf kemudi dan graf jarring
Factor Analysis on Poverty in Kalimantan Island with Geographically Weighted Negative Binomial Regression
Full text linkPoverty is one of the problems still faced by Indonesia. The problem of poverty is a development priority because poverty is a complex and multidimensional problem. Therefore, to reduce poverty, it is necessary to know the factors that influence the number of people living in poverty. The influencing factors in each region are different due to the effects of spatial heterogeneity between regions such as geographical, economic, and socio-cultural conditions. This research considers spatial factors by using the Geographically Weighted Negative Binomial Regression (GWNBR) method on poverty-based regions in Kalimantan Island. This research uses eleven independent variables. The weighting function used is the Adaptive gaussian kernel because the adaptive kernel can produce the number of weights that adjust to the distribution of observations. The stage starts with descriptive statistics and checking multicollinearity. Then proceed with the formation of Poisson Regression, because the data used is enumerated data. Then check for overdispersion. If overdispersion is detected where the variance is bigger than the mean, then Negative Binomial Regression is continued. After that, it is tested for the presence or absence of spatial heterogeneity. If there is, proceed to find the bandwidth and Euclidean distance. After that, the graphical weighting matrix is searched. Then proceed with GWNBR modeling. The results of the analysis show that there are seven significant variables, including the percentage of households with the main source of lighting is non-state electricity company (PLN), average monthly net income of informal workers, population density for every square kilometer, monthly per capita expense on food and non-food essentials, percentage of people who have a health complaint and do not treat it because there is no money and percentage of population 15 years and above who do not have a diploma. Based on the categories of significant variables, six groups were formed in 56 districts/cities in Kalimantan Island
Analysis of Potassium and Iron (Fe) Contents of Red Salak Fruit (Salacca edulis Reinw) Seram Regency, Western Part of Maluku Province
Full text linkThe snake fruit plant called red snake fruit can be found throughout Maluku, especially in Taniwel District in West Seram Regency (SBB). The flesh of the fruit is thick and dark yellow with a red tinge. The cultivation centers of red snake fruit in Riring Village and Buria Village are at different altitudes, which allows for differences in the content of primary metabolites, especially potassium content, in red snake fruit plants. The focus of the study was the potassium and iron (Fe) content of red snake fruit in the highlands (Riring Village) and lowlands (Buria Village). The first step in conducting potassium content analysis is the process of preparing red snake fruit, where the skin and flesh are peeled and separated. After that, the grass is dried for six times twenty-four hours in an oven. After that, the grass is ground into powder. The potassium content test stage uses the atomic absorption spectrophotometry (AAS) technique. Here, this step produces a solution that is used to calculate the levels of potassium and iron (Fe). The results showed that red snake fruit was positive for potassium in two different locations at different altitudes. Negeri Buria has the highest potassium content of 2.21715% and Negeri Riring has the lowest potassium content of 1.9121%. Riring Village has an iron (Fe) content of 0.0143mg/L, while Buria Village has an iron content of 0.0157mg/L. Negeri Riring has the highest potassium content of 2.21715% and Negeri Riring has the lowest potassium content of 1.9121%
Dampak Perubahan Iklim dan Hubungan Unsur Iklim Dengan Produktivitas Pala di Pulau Hatta
Full text linkDampak perubahan iklim berpengaruh terhadap produktivitas tanaman pala. Penelitian ini bertujuan melihat dampak perubahan iklim dan hubungan unsur iklim dengan produtivitas tanaman pala. Penelitian ini merupakan penelitian survei menggunakan teknik random sampling, pengambilan sampel yang diambil sebanyak 30 sampel petani. Analisis yang dilakukan yaitu analisis curah hujan pada kondisi ekstrem menggunakan data curah hujan 30 tahun terakhir Periode (1994-2023) serta analisis hubungan unsur-unsur iklim dengan produktivitas tanaman pala. Pengujian unsur-unsur iklim dengan produktivitas tanaman pala menggunakan analisis regresi yang ada pada aplikasi minitab. Hasil penelitian menunjukkan bahwa adanya dampak perubahan iklim yang ditandai dengan kejadian El Nino dan La Nina. Dimana terjadi penurunan jumlah curah hujan sebesar 50% pada tahun 2015 dan peningkatan curah hujan sebesar sebesar 67% pada tahun 2017 serta ditemukan adanya hubungan unsur iklim yang berpengaruh terhadap produktivitas tanaman pala yaitu lama penyinaran matahari