Judul: Fluctuations PM2,5 Concentration  and its Relationship with Wind Characteristics (Case study: Central Jakarta), Fluctuations PM2,5 Concentration  and its Relationship with Wind Characteristics (Case study: Central Jakarta)
Abstrak: Masalah pencemaran udara merupakan salah satu masalah yang dihadapi oleh beberapa kota besar di dunia, salah satunya adalah Kota Jakarta. Peningkatan jumlah penduduk di Jakarta mengakibatkan peningkatan kegiatan konsumsi energi baik dari sektor transportasi, maupun industri, yang dapat mengakibatkan peningkatan emisi pencemar udara, salah satunya adalah partikulat halus PM2,5. Fluktuasi konsentrasi pencemar, selain dipengaruhi sumber emisi, juga dipengaruhi faktor meteorologi, salah satunya adalah angin. Penelitian ini bertujuan untuk menganalisis fluktuasi konsentrasi PM2,5 dan hubunganya dengan karakteristik angin dengan lokasi penelitian Jakarta Pusat. Data konsentrasi PM2,5 tahun 2019 dan 2020 didapatkan dari hasil pengukuran US Embassy (Jakarta Pusat), data angin menggunakan data ECMWF. Fluktuasi konsentrasi PM2.5 dan hubungannya dengan kecepatan angin dianalisis menggunakan statistik deskriptif, uji-t berpasangan sederhana dan package open air menggunakan metode windrose dan polar plot serta analisis regresi dan korelasi. Hasil penelitian menunjukkan konsentrasi PM2.5 memiliki puncak konsentrasi pada pagi hingga siang hari, menurun saat menuju sore hari dan kembali meningkat pada saat menuju malam hari. Fluktuasi PM2,5 bulanan secara keseluruhan menunjukkan peningkatan dari bulan Januari hingga mencapai puncaknya di bulan Juni, lalu mengalami penurunan hingga bulan Desember. Hubungan kecepatan angin dengan konsentrasi PM2,5 berkorelasi negatif -0,30 pada 2019 dan -0,31 pada 2020. Hubungan komponen zonal (Barat-Timur) dengan PM2,5 korelasi negatif dengan r sebesar -0,26 pada 2019 dan -0.31 pada 2020 dibandingkan dengan komponen meridional (Utara–Selatan) berkorelasi positif dengan r yang sebesar 0.21 dan 0.12. Berdasarkan hasil R2 komponen zonal memiliki pengaruh yang lebih besar terhadap konsentrasi PM2,5¬ dengan R2 sebesar 13,90 % (2019) dan 15,03% pada 2020 dibadingkan dengan hasil R2 komponen meridional yang hanya sebesar 8,62% dan 9,52%, The problem of air pollution is one of the problems faced by several big cities in the world, one of which is the city of Jakarta. An increase in the population in Jakarta has resulted in an increase in energy consumption activities from both the transportation and industrial sectors, which can result in an increase in air pollutant emissions, one of which is PM2.5 fine particulate matter. Fluctuations in pollutant concentrations, apart from being influenced by emission sources, are also influenced by meteorological factors, one of which is wind. This study aims to analyze fluctuations in PM2.5 concentrations and its relationship with the characteristics of the wind with the research location in Central Jakarta. PM2.5 concentration data In 2019 and 2020 obtained from the US Embassy (Central Jakarta) measurement results, wind data uses ECMWF data. PM2.5 concentration fluctuations and its relationship with wind speed were analyzed using descriptive statistics, simple paired t-test and open package air using the windrose method and polar plots as well as regression and correlation analysis. The results showed the concentration of PM2.5 has a peak concentration in the morning until noon, decreases towards the afternoon and increases again towards the evening. PM2.5 fluctuation The monthly as a whole showed an increase from January to reach a peak in June, then decreased until December. Relationship between wind speed and PM2.5 concentration negatively correlated -0.30 in 2019 and -0.31 in 2020. Relationship between the zonal (West-East) component and PM2.5 has negative correlation with r of -0.26 in
Keyword: Fluktuasi konsentrasi, Partikulat (PM2,5), Kecepatan Angin, Angin Zonal, Angin Meridional

Judul: The Phenomenon of Pollution Haze and Its Relationship with PM2.5 Concentration Fluctuations in Urban Areas (Case Study: Jakarta)
Abstrak: Fenomena haze di DKI Jakarta menjadi masalah besar karena berdampak terhadap gangguan jarak pandang dan peningkatan risiko penyakit pernapasan. Pengaruh emisi antropogenik menghasilkan partikel udara kering yang dapat bercampur dengan gas-gas di atmosfer dan membentuk haze atau udara kabur. Penelitian ini bertujuan untuk menganalisis hubungan antara kejadian haze dan tingkat konsentrasi PM2.5, serta ketinggian lapisan inversi sebagai faktor pendukung. Data yang digunakan merupakan data luaran model ECMWF konsentrasi PM2.5, kode SYNOP haze, arah angin, curah hujan, dan tinggi lapisan inversi pada bulan September 2021 sampai Agustus 2023 yang dianalisis melalui visualisasi grafik, korelasi, dan regresi linier serta menggunakan Minitab 20 dan RStudio 4.2.0. Analisis ini menggunakan data pada wilayah Stasiun Meteorologi Soekarno-Hatta dengan asumsi dapat mewakili kondisi wilayah dan studi kasus di DKI Jakarta. Hasil penelitian menunjukkan frekuensi kejadian haze semakin intensif ketika ketinggian lapisan inversi terjadi di bawah 200 m bersamaan dengan tingkat konsentrasi PM2.5 di atas 60 µg/m3. Analisis hubungan keeratan kejadian haze menggunakan regresi linier berganda memiliki koefisien determinasi (R2) sebesar 65%, namun hasil p-value tinggi lapisan inversi tidak signifikan dengan kejadian haze (p-value>0,05), sedangkan konsentrasi PM2.5 signifikan kaitannya dengan kejadian haze (p-value<0,05)., The haze phenomenon in Jakarta has become a major problem due to its impact on visibility disturbances and the increased risk of respiratory diseases. The influence of anthropogenic emissions produces dry air particles that can mix with gases in the atmosphere and form haze. This study aims to analyze the relationship between haze events and PM2.5 concentration levels, as well as the height of the inversion layer as a supporting factor. The data used includes PM2.5 concentration output from the ECMWF model, SYNOP haze code, wind direction, rainfall, and inversion layer height from September 2021 to August 2023, which are analyzed through graphical visualization, correlation, and linear regression using Minitab 20 and RStudio 4.2.0. This analysis uses data from the Soekarno-Hatta Meteorological Station with the assumption that it can represent the conditions in Jakarta. The results show that the frequency of haze events becomes more intensive when the inversion layer height is below 200 m along with PM2.5 concentration levels above 60 µg/m3. The relationship analysis using multiple linear regression has a coefficient of determination (R2) of 65%, but the p-value for the inversion layer height is not significant with haze events (p-value>0.05), whereas the PM2.5 concentration is significantly related to haze events (p-value<0.05).
Keyword: antropogenik, atmosfer, jarak pandang, lapisan inversi, signifikan

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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