Judul: Horizontal Turbulence Intensity and Fluctuation Analysis Pollutant Concentration (SO2, PM10) (Case Study: Baranangsiang and Puncak Bogor)
Abstrak: Intensitas turbulensi merupakan fungsi dari kecepatan angin, baik untuk zonal, meridional dan vertikal. Turbulensi dapat menyebabkan tinggi rendahnya fluktuasi konsentrasi polutan. Penelitian ini bertujuan menganalisis bagaimana pengaruh intensitas turbulensi secara horizontal terhadap konsentrasi polutan, diantaranya adalah SO2 dan PM10 tahun 2018 di sekitar Baranangsiang dan Puncak, Bogor. Intensitas turbulensi didapatkan dengan menghitung nilai rata-rata kecepatan angin dan simpangan nilai rata-rata kecepatan angin. Intensitas turbulensi di daerah Puncak Bogor lebih fluktuatif dibandingkan daerah Baranangsiang. Konsentrasi SO2 maksimum terjadi pada siang hari sebesar 3,3 μg/m3 di Baranangsiang dan 4,2 μg/m3 di Puncak, sementara itu nilai minimum terjadi pada pagi hari sebesar 0,9 μg/m3 di Baranangsiang dan 0,5 μg/m3 di Puncak. Konsentrasi PM10 maksimum terjadi pada sore hari sebesar 63 μg/m3 di Baranangsiang dan 56 μg/m3 di Puncak, sementara itu nilai minimum terjadi pada pagi hari sebesar 45 μg/m3 di Baranangsiang dan 20 μg/m3 di Puncak. Pola mingguan SO2 dan PM10 terbesar di Baranangsiang pada awal minggu, sedangkan di Puncak terdapat pada penghujung minggu. Intensitas turbulensi berbanding lurus dengan konsentrasi polutan pada siang hari di Baranangsiang sedangkan di Puncak saat turbulensi turun polutan terus meningkat. Pada malam hari intensitas turbulensi menurun bersamaan dengan konsentrasi polutan di kedua wilayah., Turbulence intensity is a function of wind speed for zonal, meridional and vertical winds. Turbulence can cause high and low fluctuations in pollutant concentrations. This study aims to analyze how the horizontal turbulence intensity affects the concentration of pollutants, including SO2 and PM10 in 2018 around Baranangsiang and Puncak, Bogor. Turbulence intensity is obtained by calculating the mean value of wind speed and the deviation of the mean value of wind speed. Turbulence intensity in the Puncak area of Bogor fluctuates more than the Baranangsiang area. The maximum SO2 concentration occurred in the afternoon at 3.3 μg/m3 in Baranangsiang and 4.2 μg/m3 in Puncak, while the minimum value occurred in the morning at 0.9 μg/m3 in Baranangsiang and 0.5 μg/m3 in Puncak. The maximum PM10 concentration occurred in the afternoon at 63 μg/m3 in Baranangsiang and 56 μg/m3 in Puncak, while the minimum value occurred in the morning at 45 μg/m3 in Baranangsiang and 20 μg/m3 in Puncak. The weekly pattern of SO2 and PM10was greatest in Baranangsiang at the beginning of the week, while in Puncak at the end of the week. Turbulence intensity is directly proportional to pollutant concentrations during the day in Baranangsiang while in Puncak when turbulence drops pollutants continue to increase. At night the turbulence intensity decreases along with the pollutant concentration in both regions.
Keyword: correlation, dispersion, PM10, SO2, turbulence intensity

Judul: Fluctuations in SO2 Concentration in the Puncak Area (Bogor) and Their Relation to Average Wind Speeds and its Variations
Abstrak: Fluktuasi konsentrasi polutan dipengaruhi oleh jumlah emisi dan faktor meteorologi, salah satunya adalah angin baik arah maupun kecepatan. Kecepatan angin sangat berfluktuasi, sehingga penelitian ini bertujuan untuk menelaah pengaruh fluktuasi kecepatan angin terhadap fluktuasi konsentrasi polutan SO2. Analisis ini mengambil studi kasus data SO2 di wilayah Cibeureum, Puncak Bogor, yang merupakan data pemantauan kualitas udara milik BMKG bekerjasama dengan NIES Jepang. Lokasi tersebut merupakan wilayah rural, dengan asumsi fluktuasi konsentrasi SO2 di wilayah tersebut tidak banyak dipengaruhi oleh sumber emisi antropogenik. Hubungan fluktuasi tersebut dianalisis secara visual melalui grafik, analisis korelasi dan regresi dengan skala waktu 15 menit tahun 2021. Hasil analisis menunjukkan bahwa di wilayah Puncak Bogor tahun 2021, pengaruh fluktuasi kecepatan angin rata-rata terhadap fluktuasi konsentrasi SO2 lebih besar daripada pengaruh simpangan kecepatan angin. Pengaruh kecepatan angin dan simpangannya terhadap SO2 pada bulan kering lebih besar dibandingkan bulan basah, dengan pengaruh di siang hari lebih besar daripada malam hari. Pengaruh angin yang kuat terjadi pada pukul 07.00 – 12.59 WIB. Koefisien korelasi (r) kecepatan angin dengan konsentrasi SO2 pada bulan kering berkisar antara -0,15 hingga -0,73, sementara korelasi simpangan angin dengan konsentrasi SO2 berkisar antara -0,18 hingga -0,65. Pada dasarnya kecepatan angin berpengaruh negatif terhadap fluktuasi SO2, sehingga peningkatan kecepatan angin akan berpengaruh terhadap penurunan konsentrasi SO2., Pollutant concentrations fluctuate due to emissions and meteorological factors, one of which is wind, both direction and speed. Wind speed fluctuates greatly, so this study aims to examine the effect of wind speed fluctuations on SO2 pollutant concentration fluctuations. This analysis takes a case study of SO2 data in the Cibeureum area, Puncak Bogor, which is BMKG's air quality monitoring data in collaboration with NIES Japan. This location is a rural area, with the assumption that fluctuations in SO2 concentrations in that area are not much influenced by anthropogenic emission sources. The fluctuation relationship is analyzed visually through graphs, correlation analysis and regression with a time scale of 15 minutes in 2021. The results of the analysis show that in the Puncak Bogor area in 2021, the effect of fluctuations in average wind speed on fluctuations in SO2 concentration is greater than the effect of wind speed variations. The effect of wind speed and its variations on SO2 is greater in dry months than in wet months, with a greater effect during the day than at night. The correlation coefficient of wind speed with SO2 concentration in dry months ranges from -0.15 to -0.73, while the correlation of wind speed variations with SO2 concentration ranges from -0.18 to -0.65. Basically, wind speed has a negative effect on SO2 fluctuations, so an increase in wind speed will cause a decrease in SO2 concentration.
Keyword: rural, wind speed, wind speed variations, SO2

Judul: The Exploration of Discrete Logarithm over Finite Field GF(3m)
Abstrak: The security of many public~key algorithms is based on the problem of finding discrete logarithms. The generalized discrete logarithm problem is the following: given a finite cyclic group G of order n, a generator a of G, and an element fl E G, find the integer x, 0 ~ x ~ n - 1, such that 0: = fl. Algorithm for discrete logarithm problem focused on Menezes et al. (1997) that consist of exhaustive search algorithm, the baby-step giant-step algorithm, Pollard's rho algorithm, Pohlig-Hellman algorithm, and index-calculus algorithm. These algorithms are explorated to be used in discrete logarithm problem over finite field GF(3m ). The exploration also produces some algorithms, i.e. naif negative algorithm, baby-step mother-step algorithm, baby-step mother free-step algorithm, and baby-step free-step algorithm. All algorithms implemented using Maple 11. The Pohlig-Hellman and baby-step giant-step algorithms are efficient enough to be used in discrete logarithm problem over finite field GF(3m ) for m < 20.
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