Judul: Analisis dan Prediksi Pertumbuhan Jumlah Kasus COVID-19 di Pulau Jawa Menggunakan Metode Linear Regression dengan ARIMA Error
Abstrak: Coronavirus Disease 2019 (COVID-19) merupakan penyakit menular yang menyebabkan gangguan pada pernapasan dan radang paru-paru. COVID-19 ditetapkan sebagai pandemi pada 11 Maret 2020. Pulau Jawa merupakan pulau yang memiliki kasus terkonfirmasi positif COVID-19 terbanyak di Indonesia. Jumlah kasus terkonfirmasi positif COVID-19 di Pulau Jawa dapat disebabkan oleh beberapa faktor, salah satunya adalah mobilitas masyarakat. Penelitian ini melakukan analisis terkait dampak kebijakan yang diterapkan oleh pemerintah dalam menekan mobilitas masyarakat, yaitu Kebijakan Pemberlakuan Pembatasan Kegiatan Masyarakat (PPKM). Selain itu, fokus utama pada penelitian ini adalah melakukan analisis prediktif jumlah kasus terkonfirmasi positif COVID-19 menggunakan Linear Regression dengan ARIMA error. Dengan menggunakan Linear Regression dengan ARIMA error dan prediktor berupa data mobilitas didapatkan nilai MAPE pada model yang buat berkisar antara 10,90% hingga 22,93% tiap provinsinya kecuali Jawa Tengah yang memiliki nilai MAPE sebesar 47,02%., Coronavirus Disease 2019 (COVID-19) is an infectious disease that causes respiratory problems and inflammation of the lungs. COVID-19 was declared a pandemic on March 11, 2020. The island of Java is the island that has the most positive confirmed cases of COVID-19 in Indonesia. The number of positive confirmed cases of COVID-19 in Java can be caused by several factors, one of which is community mobility. This study analyzes the impact of policies implemented by the government in suppressing community mobility, namely the Policy for the Enforcement of Restrictions on Community Activities (PPKM). In addition, the main focus of this study is to carry out a predictive analysis of the number of positive confirmed cases of COVID-19 using Linear Regression with ARIMA error. By using linear regression with ARIMA error and employing the mobility predictors, we obtained a MAPE value within the range of 10,90% to 22,93% for each province, with the exception of Jawa Tengah which had a MAPE of 47,02%.
Keyword: ARIMA error, COVID-19, linear regression, PPKM

Judul: Prediction Model Number of COVID-19 Cases and Analysis Based on Demography, Social and Economy Using Long Short Term Memory (Case Study: East Java Province)
Abstrak: Coronavirus Disease 2019 atau (COVID-19) disebabkan oleh jenis virus corona baru yang dapat menimbulkan penyakit pernapasan. Penyakit ini ditemukan pertama kali di Wuhan, China, pada bulan Desember 2019. Virus ini ditularkan melalui cairan atau kontak langsung dan menginfeksi saluran pernapasan yang mengakibatkan pneumonia di sebagian besar kasus. Faktor demografi, sosial dan ekonomi merupakan faktor-faktor yang mendorong penyebaran penyakit menular. Antisipasi dan pengukuran dari berbagai faktor yang terlibat dalam penyakit menular dapat dimodelkan secara matematis dengan pemodelan matematika. Penelitian ini melakukan pemodelan prediksi kasus COVID-19 di Jawa Timur menggunakan Long Short Term Memory (LSTM). Berdasarkan hasil penelitian, kabupaten/kota di Jawa Timur terbagi menjadi lima cluster sesuai karakteristik demografi, sosial dan ekonominya. Jumlah kasus positif COVID-19 yang tinggi terdapat di cluster dengan PDRB yang tinggi. Hasil analisis regresi menunjukan bahwa atribut PDRB merupakan atribut yang berpengaruh signifikan terhadap jumlah terkonfirmasi COVID-19 di Jawa Timur. Penelitian ini memperkirakan jumlah terkonfirmasi positif COVID-19 masih terus naik hingga akhir Juli 2021., Coronavirus Disease 2019 or (COVID-19) is caused by a new type of coronavirus that can cause respiratory disease. This disease was first discovered in Wuhan, China, in December 2019. This virus is transmitted through fluids or direct contact and infects the respiratory tract resulting in pneumonia in most cases . Demographic, social and economic factors are factors that encourage the spread of infectious diseases. The anticipation and measurement of various factors involved in infectious diseases can be modeled mathematically. This research conducts predictive modeling of COVID-19 cases in East Java using Long Short Term Memory (LSTM). Based on the research results, districts/cities in East Java are divided into five clusters according to their demographic, social and economic characteristics. Many positive cases of COVID-19 are found in clusters with a high value of Gross Regional Domestic Product (GDP regional). The results of the regression analysis indicate that GDP regional attribute is an attribute that has a significant effect on the number of positive confirmed cases of COVID-19 in East Java. This study estimates that the addition of the positive number of COVID-19 will continue to rise until the end of July 2021.
Keyword: COVID-19, demographic, economic, long short term memory, prediction modeling, social

Judul: Elektrodeposisi Film Tipis Semikonduktor Cu2ZnSnS4 (CZTS) pada Substrat Kaca ITO
Abstrak: Semiconductor Cu2ZnSnS4 (CZTS) thin film that can be used as absorber layers on solar cell module was made via electrodeposition method. CZTS thin film was electrodeposited on the surface of a silicate glass coated with a thin layer of indium tin oxide (ITO). Deposition process was done using potentiostatic mode at room temperature with a potential of 1.05 V for 30, 45, and 60 minutes, followed with annealing the film at 2 different temperatures, 500 ºC using furnace and 180 ºC using hot plate, both treatments for 45 minutes in N2/H2S atmosphere. The X-ray difractograms were analyzed using Match 2 program and showed that the CZTS thin films had kesterit crystalline structure, with a low percentage of CZTS phase. The thin film also contained secondary phases such as Cu2S, ZnS, and SnS. The obtained CZTS thin films had a thickness between 1.039 and 1.676 μm. Absorption study showed that the band gap energy of CZTS thin films which was annealed using furnace ranged from 1.50 to 1.52 eV, whereas that annealed using the hot plate was not observed. The band gap energy value showed that CZTS thin films can be used as sunlight absorber layers on solar cell. The formation of CZTS crystal film on this investigation was effectively performed using furnace annealing process at a temperature of 500 ºC with deposition time of 45 minutes.
Keyword: Thin film, Electrodeposition, Cu2ZnSnS4