Judul: Sifat-sifat dasar kayu panggal buaya (Zanthoxylum rhetsa (Roxb.) D.C) asal Bali dan potensi penggunaannya
Abstrak: Penelitian ini dilaksanakan dalam rangka memaksimalkan pemanfaatan kayu Panggal Buaya (Z. Rhetsa) asal Bali agar tidak hanya digunakan sebagai bahan baku produk ukiran. Hasil penelitian memperlihatkan bahwa kayu ini berpotensi menggantikan peran kayu Jati dan juga Sungkai sebagai bahan baku mebel karena bercorak dekoratif. Kayu agak keras, masuk ke dalam Kelas Kuat III (BJ rata-rata 0.60), kestabilan dimensi cukup baik (T/R-ratio = 2.02), bagian terasnya kuning kecoklatan, gubalnya putih coklat terang keabuan, bertekstur halus merata dan berserat lurus, dengan permukaan yang mengkilap, licin tetapi tidak berlilin. Lingkaran tumbuhnya jelas. Pori-porinya semi tata lingkar, didominasi oleh sel-sel yang bergabung radial 2-3 sel, bidang perforasi sederhana, dan berisi endapan putih. Parenkimnya tipe marjinal yang membatasi riap tumbuh, sedangkan jari-jarinya dua ukuran tidak jelas, homoseluler dan berisi damar. Saluran antar sel tidak terlihat. Kayu Panggal Buaya tidak direkomendasikan sebagai bahan baku pulp dan kertas.
Keyword: Anatomical structure, Panggal buaya, Physical-mechanical properties, Zanthoxylum rhetsa, Forestry, Sungkai wood, Furniture manufacturing

Judul: Struktur Anatomi dan Sifat Fisis serta Alternatif Tujuan Penggunaan Tiga Jenis Kayu Asal Kalimantan
Abstrak: Wood is a product of living organism that has special characteristic and appearance. Every single species has its own character. Indonesia has about 4000 species of woody plants, but only 95 species have been studied comprehensively. Therefore, study on wood properties is very important not only for determining their proper utilization, but also for better processing and further treatments. Among thousands of existing wood species in Kalimantan, utilization of Belangeran (Shorea Balangeran (Korth.) Buck), Bungur (Lagerstroemia speciosa Pers.) and Medang (Cinnamomum spp.) woods is still limited and has not optimize yet. Through well understanding of their wood characteristics and properties, utilization of these three wood species become more optimize. It was hope that these three woods could be utilized as the alternative to replace the conventional species which tended to decrease year by year. The main material used is a small piece of wood (a disc 5 cm thick) extracted from tree stem at 1.3 meters above the ground from each species. From each disc, wood sample for every measurement was taken representatively following procedural standard. Macroscopic characteristics consist of wood color, figure, texture, grain, lustre, odor and hardness, while microscopic characteristics consist of pore (its arrangement and distribution, perforation plate, pitting structure on the cell wall and contain); ray parenchym (its size, composition and contain); type of axial parenchym and fiber morphology. Microscopic observation was conducted through the maceration specimens of Schlutze and the microtome specimens of Sass. Physical properties of wood consist of moisture content as well as density and specific gravity. The result showed that wood color of three species studied varied: reddish brown in Belangeran, pale brown to reddish in Bungur and yellowish brown in Medang. Heartwood and sapwood demarcation is clearly distinguished only in Belangeran wood, while growth ring is clearly only in Bungur wood. Diffuse pattern of pore was found in Belangeran and Medang woods, while ring porous pattern in Bungur wood. Generally, their vessels are solitary and radially multiple 2-4 cells. Vestured pit, tilosis and axial intercellular channels are the specific characters of Belangeran wood, while Bungur wood are vestured pit and prismatic crystal. Specific characters of Medang wood is yellowish white of amorphous material and oil cell (laticifer). Regarding to pulp and paper raw material, fiber quality of three wood species studied belong to Class III. In term of strengthness, these three wood species are suitable for structural purposes: Belangeran is for Strength Class II, while Medang and Bungur Strength Class III. Belangeran and Bungur woods are also potential as raw material of meubel and furniture.
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Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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