Judul: Pertumbuhan tanaman pokok Jati (Tectona grandis Linn F.) pada Hutan Rakyat di Kecamatan Conggeang, Kabupaten Sumedang
Abstrak: The need for teak wood processing in Indonesia is still high both for domestic demand and export wood demand. But the shortage of teak wood demand can give opportunities for people to cultivate teak on their privately land. The purpose of this research is to examine the main plant growth of teak (Tectona grandis Linn F.) in small scale private forest and compare it with teak’s growth from monoculture forest at Perum Perhutani KPH Sumedang in same ages. The main data of plant dimensional were taken with census method from teak plants in each of the selected land such as height, canopy diameter and canopy projection. In this research, soil parameter observed consist of physical and chemical content of soil samples from each selected land then analyzed in laboratory. Crown closure data taken by using a spiracle densiometer. The history of land management known by interview with farmers in each selected land. Those data were analyzed descriptively. The results showed that the observed forest have 3 (three) different age classes of teak plantation. They are teak plant with class age of 3 years, 6 years, and 12 years whom the growth of teak are different in those parameter such as diameter, height, crown closure and basal area. Growth of teak plantation in the village of Babakan Asem is a plant with the best teak growth among the other villages. Their growth maybe influenced by several factors, that is the condition of the site or soil condition factors and cultivation activities. The result of crown closure show that the majority of sunlight blocked by the crop canopy of teak, so less than 40% of sunlight can reach the soil surface. That condition maybe affected by size crop of teak and the distance between teak plantation it self. The result of soil analysis indicatedthat physical and chemical soil content in Conggeang District are impactonteak growth which bulk density, water storage, KTK, pH, and other chemical substance are related to teak diameter’s growth. Growth of teak plantation between small scale private forest and Perum Perhutani were significantly different in class ages of 3 and 12 years and didn’t different at class ages of 6 years in diameter. The difference in teak growth between small scale private forest and Perum Perhutani are caused by a factor of using teak seed and the forest management.
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Judul: Karakteristik Biometrik Pohon Jati (Tectona grandis L.f.) Studi Kasus di Bagian Hutan Bancar KPH Jatirogo, Perum Perhutani Unit II, Jawa Timur
Abstrak: One of each wood species what have most popular and to increase staple plant in forest management at work district Perum Perhutani, especially Unit I Cntral Java and Unit II East Java is teak wood (Tectona grandis L.f.). Teak wood inclusive of wood which have preserved class II and strength class II, so that’s fitting for any kind build construction. In the division from planning of forestry knowledge, one of problem research what have been develop is about biometric characteris tic from some trees. Biometric technic is some method to identification some of individual based on phisically character or from behaviour. Physical data achieved trough tree dimension measurements is needed in the process. The objective of this research is to describe teak tree (Tectona grandis L.f.) biometric characteristics in various age level and relationship from this character what have consistently property and unique. Hopefull, this research will enrich science trough information on teak tree biometric characteristics. Beside that, result of this research hopefully can useful include to tarif or tabel local volume from teak trees after which advance, can useful in planning forestry knowledge and to increase a dendology knowledge. The research was conducted at forest division Bancar KPH Jatirogo Perum Perhutani Unit II East Java in March until April 2008. The research object were 40 teak trees samples at various age level and bonita which the trees has diameter breast height minimum 20 cn and chosen by purposive sampling. Tools used were phiband, haga Hypsometer, Spiegel Relascop Bieterlich type wide scale, rope, tally sheet, camera, and write tools. Dimension measured were foot diameter (Dp), diameter breast high (Dbh), clear length bole diameter (Dbc), diameter each section, crown diameter (Dtk), tall stem which 2 meters for each section, total height (Tt), crown height (Ttk) and clear length bole height (Tbc) of each tree samples. Tree volume was measured using by Smalian formula. Form factor measured were breast high form factor and absolute form factor. Form quotients measured were normal form quotients and absolute form quotients. Data analysis was done by statistically describe tree dimension, measured the ratio between each dimension, analyzed the correlation between each tree dimension, between tree dimension and actual volume, stem form factors value and form quotients value, and analyzed the correlation between form factor and actual volume with diameter ratio. Regression equation model was made using all the related correlations. The data were analyzed using sotware Microsoft Excel and Minitab version 14. The result were as follows range of diameter breast height : 21,02 - 84,08 cm; foot diameter : 24,84 - 102,87 cm; clear length bole diameter : 10,00 - 60,00 cm; crown diameter : 7,75 - 21,50 cm; total height : 12,50 - 31,50 cm; clear length bole height : 7,50 - 20,50 cm; and crown height : 4,50 - 21,00 cm. Mean ratio between dimension : Dp/Dbh = 1,242 ; Dp/Dtk = 0,043 ; Dbc/Dtk = 0,019 ; Dbc/Dp = 0,461 ; Dbc/Dbh = 0,571 ; Dbh/Dtk = 0,034 ; Tbc/Tt = 0,553 ; Ttk/Tt = 0,447 ; Tbc/Ttk = 1,352. Teak stem coeficient is
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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