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Abstract. Ikhsan M, Hadi UK, Soviana S. 2020. Diversity and distribution bromeliads plants as breeding habitat for mosquito larvae (Diptera: Culicidae) in Bogor, Indonesia. Biodiversitas 21: 3494-3498. Bromeliads leaf structure can hold water and has potential as the breeding ground for mosquitoes. Information regarding the potential of bromeliads as a habitat for mosquito larvae in Indonesia is limited. This study aims to identify the diversity of bromeliads and their potential as breeding habitat for mosquito larvae in West Bogor Sub-district, Bogor City, West Java, Indonesia. Determination of the sample using purposive sampling method. Larvae collections were carried out on bromeliads that were outside the building in December 2019 to Maret 2020. The collection used a 50 ml syringe that was modified using a small pipe. Total bromeliads collected were 117 consisted of Neoregelia, Cryptanthus, dan Alcantarea from 50 observation points. The percentage of mosquito larvae presence from bromeliads was 74.4%. Total larvae collected were 859 larvae consisting of Aedes albopictus, Aedes aegypti, Aedes spp., Armigeres subalbatus, and Culex quinquefasciatus. The diversity of mosquito larvae found in the bromeliads were low (H'=0.16), while the dominant species of mosquito larvae were Ae. albopictus (61.55%) and confirmed as the second vector of Dengue Fever in Indonesia. The results of this study indicate that bromeliads have potential as a breeding site for mosquito larvae in West Bogor Sub-district, Bogor City.

Abstract. Ikhsan M, Priyambodo S, Nurmansyah A, Hendarjanti H, Sahari B. 2020. Species diversity, abundance and damaged caused by rats in oil palm plantation in West and Central Sulawesi, Indonesia. Biodiversitas 21: 5632-5639. Oil palm is one of the plantation commodities which has an important role in Indonesia’s economy. Indonesia is the largest producer and exporter of oil palm in the world with its export value capable of supplying 55.78% of global consumption. Rats are wild animals that are important pests for human life, both in agriculture plantations and urban areas. Rats can damage crops at various stages of plant growth. This study was aimed to determine the species abundance of rats in oil palm plantations, calculate the severity of crop damage due to rats infestation. Three blocks of mature plants were used in OC and OH plantation blocks were used to calculated, crop damage caused by rats, Identify the species of rats, and estimated rats abundance. The results of these studies showed there were four species of rats found in the oil palm plantation, namely Rattus tiomanicus, R. tanezumi, Rattus sp, and Maxomys hellwaldii. However, only R. tiomanicus and R. tanezumi were dominant species. There were significant differences in the number of, sex, and body weight between R. tiomanicus and R. tanezumi. The OC 12 block had the lowest infestation intensity than the other blocks since it was well maintained. The OH 02 block had the highest infestation intensity, infestation area, and abundance due to a lack of maintenance.

CCTV cameras have an important function in the field of public service, especially for convenience. The objects recorded through CCTV cameras are processed into information to support service satisfaction in the community. This study uses the function of CCTV for people counting from objects recorded by a camera. Currently, the process of detecting and tracking people takes a long time to detect all frames. In this study, the frame selection into keyframes uses the mutual information entropy method. The keyframes processing uses the Histogram of Oriented Gradient (HOG) and Kalman filter methods. The proposed method results F1 value of 0.85, recall of 76 %, and precision of 97 % with winStride parameter (12,12), scale 1.05, and the distance of the human object to CCTV 4 meters.

ABSTRAKTelah dilakukan sintesis magnetit dari biji besi Nagari Surian Kecamatan Pantai Cermin Kabupaten Solok Sumatera Barat dengan metode kopresipitasi. Selanjutnya dari magnetit tersebut disintesis maghemit tanpa dan dengan penambahan PEG melalui oksidasi pada temperatur 400 o C selama 3 jam. Variasi PEG yang digunakan yaitu sampel tanpa penambahan PEG, sampel dengan penambahan PEG-2000, PEG-4000, dan PEG-6000. Maghemit yang dihasilkan dikarakterisasi sifat magnetik menggunakan Vibrating Sample magnetometer (VSM). Karakterisasi sifat magnetik menggunakan VSM menghasilkan nilai koersivitas berturut-turut yaitu 250 Oe, 193 Oe, 203 Oe, 178 Oe. Terlihat bahwa penambahan PEG mengurangi nilai koersivitas maghemit. ABSTRACTSynthesis of magnetite from Nagari Surian Sumatera Barat was performed using coprecipitation method. Then maghemite was syinthesized from that magnetite using oxidation at temperature 400 o C in 3 hour with and without adding PEG. Variations of PEG used are PEG-2000, PEG-4000, and PEG-6000 respectively. Then the maghemite is characterized by its electrical properties and magnetic properties. Characterization of magnetic properties using Vibrating Sample magnetometer (VSM) show that coersivity are 250 Oe, 193 Oe, 203 Oe, 178 Oe respectively. From the result it is seen the addition of PEG reduce the value of coersivity.