Judul: Distribution and genetic diversity of hoya multiflora blume (asclepiadaceae) populations at gunung gede pangrango national park and sukamantri of Gunung Halimun Salak National Park
Abstrak: Hoya multiflora is one of the valuable germplasm in Indonesia that has been utilized as ornamental and medicinal plants. This epiphytic plant faces problems in decreasing habitat. Study on population distribution, habitat and genetic diversity of this species has been conducted at the Gunung Gede Pangrango National Park (GGPNP) and Sukamantri of Gunung Halimun Salak National Park (GHSNP). According to this observation, the populations of this species were found at the Bodogol Research Station of GGPNP and Sukamantri of GHSNP at elevation of 700 - 900 m above sea level (asl). There were also two individual plants observed at Situ Gunung of GGPNP at 1000 m asl and there is no evidence of this species at GGPNP and Sukamantri at above 1000 m asl. The populations showed the clumped type of dispersion (Morisita's lndex = 1.35) indicated environment characterized by patchy resources. According to the type of its parachutes type seed dispersal by wind, the direction and speed of wind coupled with the topography will affect to the distribution of this species. This plant also recorded to evolve association with several species of ants in the location but not in the obligate type. H. multiflora have been utilized various species of trees as phorophyte, especially which have inhabitant by ants. The preference was at the phorophyte provided media i.e. humus dependent. The type of vegetation as habitat was varied at dominant species and density. The habitat condition was varied at canopy cover (30-90 %), light intensity (30-80%), temperature (25-32 oC) and air humidity (70-98 %). Population genetic diversity studies consist of morphological and AFLP-DNA markers from 6 sub populations, 3 sub populations from Bodogol and 3 sub populations from Sukamantri. The data was run on POPGENE 32 software. The population diversity was low based on both morphological characters and AFLP-DNA markers. The genetic differentiation among sub population is moderate to high, therefore it needs conservation. According to cluster analysis based on morphological characters and AFLP-DNA markers, 6 sub populations were classified as five populations, i.e. two population at Bodogol and three populations at Sukamantri.
Keyword: 

Judul: Morphological characterization of Hoya diversifolia Blume growing spontaneously in Bogor Botanical Garden
Abstrak: Hoya diversifolia merupakan tumbuhan epifit yang tumbuh subur pada berbagai inang dengan karakter batang berkulit tebal, kasar, dan retak– retak. Penelitian ini bertujuan untuk mengkarakterisasi tumbuhan H. diversifolia dan menyeleksi tumbuhan H. diversifolia terbaik yang tumbuh spontan di Kebun Raya Bogor untuk dikembangkan sebagai tanaman hias. Karakterisasi dilakukan terhadap karakter kualitatif dan kuantitatif organ vegetatif dan generatif dari 30 individu H. diversifolia. Selanjutnya data ditabulasikan dalam bentuk matrik dan digunakan untuk membangun dendogram dengan index RT (Rogers and Tanimoto) dan metode UPGMA. Hoya diversifolia bervariasi pada warna dan ukuran bunga, daun, dan batang. Berdasarkan karakter kualitatif dan kuantitatif, ditemukan individu H. diversifolia yang berpotensi dikembangkan sebagai tanaman hias. Individu ini memiliki sembilan pedunkel dengan rata- rata 18 pedicel disetiap pedunkel., Hoya diversifolia is an epiphytic plant that thrives on various of host stem with thick-skinned, rough, and cracked character. This study aimed to characterize H. diversifolia plants and selecting the best plants that grow spontaneously in the Bogor Botanical Garden to be developed as an ornamental plant. Morphological characterization of qualitatif and quantitative characters was observed from vegetative and generative organs of 30 individuals of H. diversifolia. Furthermore, the data were tabulated and used to construct a dendogram using index RT (Rogers and Tanimoto) and UPGMA method. H. diversifolia varied in color and size of flowers, leaves, and stems. Based on qualitative and quantitative characters, there was an individual of H. diversifolia potentially to be developed as an ornamental plant. This variant had nice peduncle with 19 pedicel each peduncle. Keywords: Hoya diversifolia Blume, Morphology, Bogor Botanical Garden
Keyword: Hoya diversifolia Blume, morfologi, Kebun Raya Bogor

Judul: Desain Sistem Transfer Energi Nirkabel Berbasiskan Tesla Coil
Abstrak: Tesla coil merupakan alat yang ditemukan oleh Nikola Tesla yang dapat mentransmisikan daya tanpa kabel dengan memanfaatkan prinsip induksi elektromagnetik. Pada penelitian ini dibuat sebuah prototype Tesla Coil dengan menggunakan transistor C1970 dan receiver menggunakan rangkaian LC. Identifikasi alat meliputi pengaruh daya input transmitter terhadap receiver, bentuk signal yang dipancarkan transmitter, pengaruh jarak transmitter dan receiver, nilai efisiensi serta efek alat terhadap perangkat lain. Hasil pengamatan menunjukkan bahwa semakin besar daya input maka semakin besar daya yang dipancarkan oleh transmitter. Bentuk sinyal yang dipancarkan oleh transmitter berupa gelombang listrik AC sinusoidal dengan frekuensi ~2.9 MHz. Semakin jauh jarak receiver terhadap transmitter maka semakin kecil amplitudo gelombang AC yang diterima oleh receiver, menyebabkan semakin kecil daya yang diterima oleh receiver. Adapun nilai efisiensi terbesar penangkapan daya oleh receiver yaitu sebesar 0.00516 % serta terdapat gangguan pada alat-alat tertentu seperti monitor komputer dan radio.
Keyword: rangkaian LC, receiver, tesla coil, transistor C1970, transmitter