Judul: Penyusunan Kunci Identifikasi pada Anakan Jenis-jenis Anggota Marga Shorea Roxb. ex Gaertner f.
Abstrak: Tingginya keanekaragaman jenis pohon menjadikan manusia sejak lama memanfaatkan sumberdaya hutan tersebut baik untuk keperluan pangan, sandang, maupun papan. Untuk memudahkan kegiatan pemanfaatan tumbuhan, perlu adanya pengetahuan mengenai pengenalan identitas jenis pohon. Jenis-jenis pohon andalan Indonesia salah satunya berasal dari suku Dipterocarpaceae, yaitu kayu meranti dari marga Shorea. Pengelolaan kawasan hutan penghasil kayu meranti perlu dilakukan agar produktivitas kayu tetap terjaga, salah satunya melalui pengelolaan regenerasi alaminya. Identifikasi jenis dalam tingkat anakan menjadi sangat penting agar tidak terjadi kesalahan pemeliharaan jenis yang tidak diinginkan. Penelitian dilakukan dengan mencatat data morfologi dari 43 jenis Shorea spp. pada fase semai dan pancang yang sudah teridentifikasi hingga nama spesiesnya. Penelitian dilaksanakan mulai bulan Januari hingga April 2019 di Persemaian Kantor Pusat Penelitian dan Pengembangan Hutan, Kota Bogor. Selanjutnya data diolah sehingga dihasilkan kunci identifikasi marga Shorea. Ciri morfologi khusus dari anakan marga Shorea yaitu memiliki pertulangan tersier daun tangga (scalariform veination), ditemukannya kelenjar (gland) yang menyebar pada lamina, terdapat stipule atau daun penumpu, dan mayoritas bentuk petiole yang membengkak (swollen) dan melutut (geniculate).
Keyword: anakan, Dipterocarpaceae, kunci identifikasi, morfologi, Shorea

Judul: Identifikasi jenis shorea menggunakan jaringan syaraf tiruan propagasi balik berdasarkan karakteristik morfologi daun
Abstrak: Dipterocarpaceae is a major timber tree of tropical rain forest. Shorea is a genus of the Dipterocarpaceae family which consists of around 194 species. Species diversity may lead to difficulty in distinguishing species of Shorea of one another. It takes knowledge from an expert in the field of Shorea to be able to identify the types of Shorea. Errors in identifying the type of Shorea wood can lead to inappropriate selection for the final usability. Identifying the type of Shorea carried out on five species of Shorea owned Bogor Botanical Gardens on the basis of morphological characteristics of leaves. The identification was carried out using Backpropagation Neural Network. To obtain the values of each leaf morphological characteristics of Shorea, each sample measurement data collected manually. The values are then processed using Backpropagation Neural Network to get the pattern from the training and the accuracy of the test phase. This research used a total of 50 data from five species of Shorea. The data are divided into five subsets. The fifth subset is used in the training and testing phases and conducted five times. The use of methods Backpropagation neural networks in identifying species Shorea produces an average accuracy of 90%.
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Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model