Judul: Sifat Kelistrikan Kayu Pinus (Pinus merkusii Jungh et de Vr.) dan Kayu Puspa (Schima wallichii Korth.)
Abstrak: Electrical properties of wood such as impedance, conductance, conductivy, capasitance, dielectric constant, inductance and resistance of pine (P. merkusii) and puspa (S. wallichii) at the frequency of 103 to 106 Hz have been studied. Wood samples were from basal, middle and top portions of a single stem of each species, while all measurement was conducted on longitudinal, radial and tangential directions. Results showed that at the frequency of 103 to 106 Hz, electrical properties were significantly influenced by wood species, sample location and direction of measurement. Effect of species was more significant. The higher of impedance, resistance and/or inductance resulted in the smaller of conductance, conductivity, capacitance and dielectric constant. In general, puspa wood is more conductive to electricity than pine wood. Both pine and puspa woods are considered as a semiconductor material at the frequency of 106 Hz.
Keyword: Bogor Agricultural University (IPB), electrical properties, Schima wallichii, puspa, Pinus merkusii, pine

Judul: Sifat Mekanis Kayu Pinus (Pinus merkusii Jungh. et de Vriese) Berbagai Strain Asal Sumatera
Abstrak: Pinus (Pinus merkusii) merupakan salah satu jenis kayu yang banyak digunakan oleh industri perkayuan di Indonesia. Berdasarkan sebaran alaminya, pinus berada pada tiga lokasi di wilayah Sumatera, yaitu Aceh, Tapanuli, dan Kerinci. Pengujian sifat mekanis dapat dipengaruhi oleh beberapa faktor seperti teknik silvikultur dan kedalaman kayu dalam satu log. Penelitian ini bertujuan menganalisis sifat mekanis akibat perbedaan teknik silvikultur, bentuk spesimen, serta kedalaman kayu pada tiga strain pinus asal Sumatera. Pengujian sifat mekanis dilakukan menggunakan metode non destruktif dan destruktif. Faktor teknik silvikultur, faktor spesimen uji, faktor posisi transduser, dan kedalaman kayu serta interaksinya tidak memberikan pengaruh terhadap nilai yang dihasilkan pada pengujian non destruktif. Faktor teknik silvikultur dan kedalaman kayu, serta interaksinya tidak berpengaruh nyata terhadap nilai sifat mekanis yang dihasilkan pada pengujian destruktif. Namun demikian pada pengujian lentur statis, faktor kedalaman kayu berpengaruh terhadap nilai yang dihasilkan. Hal itu kemungkinan terjadi karena adanya perbedaan nilai kerapatan dan berat jenis pada sampel uji lentur statis di bagian gubal dan terasnya., Pine (Pinus merkusii) is one type of wood that is widely used by the wood industry in Indonesia. Based on its natural distribution, pine is located in three locations in Sumatra, namely Aceh, Tapanuli, and Kerinci. Mechanical testing can be affected by several factors such as silvicultural techniques and wood depth in one log. This study aimed to analyze the mechanical properties due to difference silvicultural techniques, specimen, and wood depth in three strains from Sumatera. Mechanical properties test is carried out using non-destructive and destructive methods. The silvicultural technique factor, the specimen factor, the transducer position factor, and the depth of the wood and their interactions did not affect the value in the non-destructive test. Silvicultural technique factors and wood depth, as well as their interactions have no significant effect on the value of the mechanical properties in the destructive test. Furthermore, the wood depth factor affects the resulting value on the static bending test. This may be due to differences in the density and specific gravity values of the static bending test samples in the sapwood and heartwood.
Keyword: mechanical properties, pine, silviculture technique, strain

Judul: Query Expansion based on Bilingual Dictionary Using Conditional Probability
Abstrak: Query expansion is a technique that can be used to bridge vocabulary gaps between queries and documents in the collection. With query expansion, user will be helped to formulate queries well so that user will optimize the search result. In this study, the expansion term was resulted from the translation of bilingual dictionary. Subsequently, several terms of expansion were elected based on the closeness of its relationship with the original query. This research showed that conditional probability can be used to select expansion term in bilingual translation method query expansion. The result of 1000 documents was more than 97% relevan document can be retrieved by this system. The more expansion term used, the larger number relevan document was retrieved.
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