Judul: Identifikasi Toleransi Tanaman Lanskap terhadap Naungan
Abstrak: Light is an important factor in plants photosynthesis process, while photosynthesis is a key of other metabolic processes in plants. Factors of light and plants shade tolerance in a landscape design is an important thing to be consider in order to safeguard the landscape ecosystem, which is able to generate the visually and ecologically suitable and sustainable design product. The method used in this study is a descriptive survey. The output of this identification is a list of shade-tolerant plants. Results of the identification indicate that adaptation of plants to the shade is different, which at leaf organs can be raised through increased chlorophyll pigment (leaves are dark green), in the number of leaves (dense canopy), and increased leaf area (widened). The stability of increase number of leaves, leaf surface area, and good leaf color performance according to the visual features of the plant indicated a high level of plant tolerance to shade.
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Judul: Morphophysiological and Anatomical  Responses of Sun and Shade Plants to Sunlight Intensity Stress
Abstrak: Setiap tumbuhan mempunyai kebutuhan intensitas cahaya tertentu. Apabila tumbuhan menerima intensitas cahaya yang tidak sesuai dengan kebutuhannya, akan menyebabkan pertumbuhan dan perkembangan yang berbeda. Tujuan penelitian ini adalah untuk mengetahui perbedaan ciri morfologi, fisiologi, dan anatomi tanaman suka sinar matahari (Catharanthus roseus) dan suka teduhan (Spathiphyllum sp.) yang ditanam pada berbagai tingkat intensitas cahaya, yakni naungan 0% (sinar matahari penuh), 50% dan 95%. Tanaman dinaungi menggunakan paranet berkerapatan berbeda di Kebun Percobaan Leuwikopo, Kampus Dramaga, IPB University. Analisis fotosintesis dilakukan menggunakan Li-6400 portable photosynthesis system dengan Photosynthetic Photon Flux Density (PPFD) 2000, 800 dan 50 µmol/m/s. Biomassa terbesar terjadi pada naungan 50% untuk kedua jenis tanaman, dan menurun pada naungan yang lebih tinggi pada tapak dara, dan kondisi sinar matahari penuh pada peace lily. Kandungan klorofil, luas, dan sudut daun meningkat seiring dengan penambahan naungan. Perlakuan naungan tidak berpengaruh nyata terhadap kadar air total kedua jenis tanaman. Asimilasi CO2 (Pn) terbaik terukur dengan PPFD 800 dan 2000 µmol/m/s, pada tanaman naungan 50%, meskipun tidak berbeda nyata dengan tanaman naungan 0% dan 95%. Hal ini menunjukkan perlakuan naungan tidak menyebabkan kerusakan perangkat fotosintesis. Struktur jaringan daun terbaik (rapat) dimiliki tapak dara naungan 0% dan peace lily naungan 95%., Plant species have certain requirement for light intensity, therefore if plants receive inappropriate light intensity, it will cause adverse growth and development. The aim of this research was to observe differences in the morphological, physiological, and anatomical characteristics of sun plant periwinkle (Catharanthus roseus) and shade plant Spathiphyllum sp. grown at different levels of light intensity, i.e., 0% shade (full sunlight), 50% shade, and 95% shade. Light intensity treatment was provided by placing the plants under para-net with different density in Leuwikopo Experimental Garden, Dramaga Campus, IPB University. Photosynthesis analysis was carried out using the Li-6400 portable photosynthesis system, with Photosynthetic Photon Flux Density (PPFD) adjusted at 2000, 800 and 50 µmol/m/s. The largest biomass resulted in 50% shade for both types of plants, which decreased significantly by higher shading for periwinkle, while for peace lily it decreased under full sunlight. Chlorophyll content, leaf area and leaf angle increased with the intensed shade density. Shading treatment had no significant effect on total water content of both plant species. The best photosynthetic CO2 assimilation (Pn) measured with PPFD 800 and 2000 µmol/m/s occurred in the plants treated with 50% shading, even though not significantly different with the plants without shading and with 95% shading, suggesting that shading treatments did not cause the damage of photosynthetic apparatus. The most compact anatomical structure was shown by the periwinkle with 0% shading and the peace lily with 95% shading.
Keyword: Catharanthus roseus, chlorophyll, photosynthesis, shade, Spathiphyllum sp

Judul: Model Peramalan Harga Minyak Mentah OPEC Menggunakan ARIMA melalui Ensemble Empirical Mode Decomposition
Abstrak: Harga minyak mentah dunia mengalami fluktuasi setiap harinya. Salah satu sumber minyak mentah yang diperdagangkan pada skala internasional yaitu minyak dari negara-negara pengekspor minyak mentah dunia yang tergabung dalam Organization of the Petroleum Exporting Countries (OPEC). Sekitar empat puluh persen dari total produksi minyak dunia merupakan produksi OPEC. Hal tersebut menjadikan peramalan harga minyak mentah OPEC sangat dibutuhkan untuk menjaga keseimbangan pasar minyak dunia. Data harga minyak yang fluktuatif dibuat lebih sederhana dan mudah diinterpretasikan dengan cara menerapkan metode Ensemble Empirical Mode Decomposition (EEMD). Metode EEMD menguraikan data menjadi sejumlah Intrinsic Mode Function (IMF) dan sisaan IMF. Pada penelitian ini dibandingkan model peramalan ARIMA dengan menggunakan data asli dan hasil dekomposisi berupa komponen IMF dan sisaan IMF. Perbandingan kedua metode dilihat berdasarkan keseluruhan dan rata-rata nilai MAPE hasil peramalan pada lima rentang waktu. Metode EEMD-ARIMA memiliki rata-rata nilai MAPE sebesar 9,09% dan simpangan baku nilai MAPE sebesar 7,39%. Peramalan harga minyak mentah OPEC pada bulan Januari-Agustus 2021 berkisar antara 42,22 sampai 60,6 US dollar per barel. Hasil akhir analisis pada penelitian ini menunjukkan bahwa metode ARIMA dengan data dekomposisi (EEMD-ARIMA) lebih baik dibandingkan metode ARIMA menggunakan data asli., World crude oil prices fluctuate every day. One source of crude oil traded is oil from crude oil exporting countries that are members of the Organization of the Petroleum Exporting Countries (OPEC). In the total of 40% of world crude oil is produced by OPEC. This makes forecasting the price of crude oil OPEC’s policy very necessary in order to maintain world oil market stability. Fluctuating oil price data is made simpler and easier to interpret by applying the Ensemble Empirical Mode Decomposition (EEMD) method. The EEMD method decomposes the data into a number of Intrinsic Mode Functions (IMF) and residual of the IMF. In this study, the ARIMA forecasting model is compared using the original data and the decomposition results in the form of IMF components and IMF residuals. The comparison of the two methods is seen based on the overall and average MAPE value of the forecasting results in five time ranges. The EEMD-ARIMA method has an average MAPE value of 9.09% and standard deviation MAPE value of 7.39%. OPEC crude oil price forecast in January-August 2021 ranges from 42.22 to 60.6 USD per barrel. The final result of the analysis in this study shows that the ARIMA method with decomposition data (EEMD-ARIMA) is better than the ARIMA method using original data.
Keyword: ARIMA, EEMD, EMD, forecast, OPEC crude oil price