Judul: Prediction Pest and Disease Attacks of Pepper Using the North American Multi-Model Ensemble Prediction Model of Precipitation.
Abstrak: Lada (Piper nigrum L.) merupakan jenis tanaman rempah yang memberikan kontribusi besar dalam kegiatan ekspor di Indonesia. Kontribusi lada sebagai komoditi ekspor tidak lepas dari berbagai ancaman yang memengaruhi proses produksinya seperti serangan hama dan penyakit. Tujuan penelitian ini ialah untuk membangun model prediksi serangan hama penggerek batang dan penyakit busuk pangkal batang memanfaatkan data prediksi curah hujan luaran model North American Multi- Model Ensemble (NMME). Data curah hujan dan data serangan hama dan penyakit (HPT) lada hasil observasi dapat digunakan untuk membangun model prediksi serangan HPT lada melalui persamaan regresi untuk menentukan nilai ambang batas curah hujan. Hasil prediksi tingkat serangan penyakit busuk pangkal batang lada menggunakan data training divalidasi dengan data serangan penyakit observasi menunjukkan hasil yang sesuai sebesar 45%, mendekati 25%, dan tidak sesuai 30%. Sedangkan, prediksi serangan hama penggerek batang menunjukkan hasil yang mendekati sebesar 40%, sesuai 40%, tidak sesuai 20% setelah divalidasi dengan data serangan hama observasi. Hasil prediksi untuk serangan penyakit yang terjadi tahun 2022 adalah rendah/sangat rendah pada triwulan pertama, rendah pada triwulan kedua, tinggi pada triwulan ketiga, dan sangat rendah pada triwulan keempat. Sedangkan untuk serangan hama pada tahun 2022 akan terjadi serangan rendah/tinggi pada triwulan pertama, rendah/tinggi pada triwulan kedua, dan tinggi untuk triwulan ketiga., Pepper (Piper nigrum L.) is a type of spice plant that makes a major contribution to export activities in Indonesia. The contribution of pepper as an export commodity cannot be separated from various threats that affect production process such as pests and diseases. The purpose of this study was to develop pest (stem borer) and disease (stem base rot disease) prediction model using the precipitation data the North American Multi-Model Ensemble (NMME). Precipitation data and pepper pest and disease attack (P&D) data from observations can be used to build a prediction model for pepper P&D attacks through a regression equation to determine the rainfall threshold value. Prediction results of pepper stem base rot disease using training data were validated with observational disease attack data showing the appropriate results of 45%, approach to 25%, and 30% inappropriate. Meanwhile, the prediction of stem borer attacks showed results that were approach to 40%, appropriate at 40%, and inappropriate at 20% after being validated with observation pest attack data. The prediction results show thatdisease attacksthat will occur in 2022 are low/very low for the first quarter, low for the second quarter, high for the third quarter, and verylow forthe fourth quarter. As for pest attacksin 2022, there will be low/high attacksin the first quarter, low/high in the second quarter, and high in the third quarter.
Keyword: ambang batas, hama dan penyakit lada, NMME, prediksi, tanaman lada

Judul: Potensi Sebaran Hama Penggerek Batang dan Penyakit Busuk Pangkal Batang Lada di Kabupaten Lampung Utara
Abstrak: Lada adalah salah satu komoditas ekspor Indonesia di bidang perkebunan mengalami penurunan hasil yang salah satunya dapat disebabkan oleh faktor serangan hama dan penyakit. Pertumbuhan dan perkembangan hama dan penyakit salah satunya dapat dipengaruhi iklim suatu daerah. Penelitian ini bertujuan menganalisis potensi sebaran hama penggerek batang (Lophobaris piperis) dan penyakit busuk pangkal batang lada (Phytophthora capsici) berdasarkan nilai Ecoclimatic Index (EI), serta mengetahui potensi kerugian akibat hama penggerek batang (Lophobaris piperis) dan penyakit busuk pangkal batang lada (Phytophthora capsici) di Kabupaten Lampung Utara. Ecoclimatic Index (EI) merupakan luaran Model Climex berdasarkan karakteristik fisik spesies dan faktor iklim Kabupaten Lampung Utara pada tahun 2009-2018. Nilai EI hama penggerek batang dan penyakit busuk pangkal batang lada tergolong sesuai hingga sangat sesuai. Potensi sebaran tertinggi hama penggerek batang dan penyakit busuk pangkal batang lada berlokasi di Kecamatan Sungkai Jaya. Potensi sebaran terendah hama penggerek batang berlokasi di Kecamatan Kotabumi Selatan dan penyakit busuk pangkal batang lada berlokasi di Kecamatan Kotabumi Selatan dan Abung Tinggi. Secara umum, potensi sebaran bulanan hama penggerek batang dan penyakit busuk pangkal batang lada memiliki pola yang sama, dimana pola fluktuasi bulanan tinggi pada musim hujan. Potensi kerugian hasil lada berbanding lurus dengan luas serangan hama penggerek batang dan penyakit busuk pangkal batang lada. Serangan yang tinggi dapat menyebabkan kerugian hasil yang tinggi., Pepper is one of Indonesia's agricultural export commodities, which has been experiencing a decrease in yield, partly due to factors such as pest and disease attacks. The growth and development of pests and diseases can be influenced by the climate of an area. This study aims to analyse the potential distribution of pepper stem borer pest (Lophobaris piperis) and pepper stem base rot disease (Phytophthora capsici) based on the Ecoclimatic Index (EI) value, and determine the potential losses due to pepper stem borer pest (Lophobaris piperis) and pepper stem base rot disease (Phytophthora capsici) in North Lampung Regency. Ecoclimatic Index (EI) is the output of the Climex Model based on the physical characteristics of species and climatic factors of North Lampung Regency in 2009-2018. The EI values of pepper stem borer pests and pepper stem base rot disease are classified as suitable to highly suitable. The highest potential distribution of pepper stem borer pests and pepper stem base rot disease is located in Sungkai Jaya sub-district. The lowest potential distribution of pepper stem borer pests is located in Kotabumi Selatan sub-district and pepper stem base rot disease is located in Kotabumi Selatan and Abung Tinggi sub-districts. In general, the potential monthly distribution of stem borer pests and pepper stem base rot disease has the same pattern, where the monthly fluctuation pattern is high in the rainy season. The potential yield loss of pepper is directly proportional to the extent of pepper stem borer infestation and pepper stem base rot disease. High infestation can lead to high yield losses.
Keyword: Black Pepper, Climex, Ecoclimatic Index, Lophobaris Piperis, Phytophthora Capsici

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology