Judul: Tabel Berat Pohon Tegakan Akasia Mangium (Acacia mangium Willd) (Studi Kasus di IUPHHK-HA PT. Bumi Pratama Usaha Jaya Sumatera Selatan)
Abstrak: The availability of tools in a Comprehensive Forest Inventory Periodic activities (IHMB) are necessary to speed up the activities and minimize the errors that occur in the measurement. The purpose of this research is composing the tree weight table of Acacia mangium (Acacia mangium Willd) species in IUPHHKHA PT. Bumi Pratama Usaha Jaya. Results of the regression analysis were taken into three categories that can indicate good or bad for an equation is the coefficient of determination ( ), standard error (SE) and count. The model validation can be performed using the aggregation deviation test (SA), the average deviation (SR), the RMSE (Root Mean Square Error), the value of the bias and real difference test conducted with the chi-square test between the alleged weight with the weight of fact table. Based on the results obtained, the equation can be used to infer a tree weight with skin and without skin based on the diameter in IUPHHK-HA Acacia mangium plant area of PT. Bumi Pratama Usaha Jaya each have Bdk = 0,4799 D1,9109 equation for tree weight with skin and Btk = 0,2096 D2,0841 equation for tree weight without skin.
Keyword: Bogor Agricultural University (IPB), model validation, regression analysis, tree weight table

Judul: Model persamaan alometrik massa karbon akar dan root to shoot ratio biomassa dan massa karbon pohon Mangium (Acacia mangium Wild): studi kasus di BKPH Parung Panjang, KPH Bogor, Perum Perhutani unit III, Jawa Barat dan Banten
Abstrak: Climate change is one of the current important environmental problems due to global warming which is caused by the increase of green house gasses concentration in the atmosphere. Through the process of photosynthesis, vegetation absorbs carbon and releases the carbon through the process of respiration. In this process, vegetation uses CO2 for the process of photosynthesis and produces O2 and energy. Some energy is stored in form of biomass. Acacia mangium is a tree species that belong to fast growing species and it is estimated to have high capability to absorb carbon. Therefore the planting of A. mangium is an important mitigation effort to reduce CO2 concentration in the atmosphere. This study had objective to obtain the model of allometric equations for the mass of tree roots of A. mangium, root to shoot ratio of biomass and carbon mass of A. mangium trees. Selection of sample trees on each dimater class was carried out by purposive sampling method. Estimation of carbon mass was applied for each part of tree consisting of roots, stems, twigs, branches, and leaves. Laboratory works were conducted for the tree samples to identify carbon content of every part of the trees. The model of allometric equation for A. mangium roots carbon mass to the diameter of trees was CA = 0,0048977D2,56 and the model of allometric equation for A. mangium roots biomass to the diameter of trees was WA = 0,00134896D2,46. The models of allometric equations for carbon mass of A. mangium tree roots to above ground biomass of tree carbon were as follows: root carbon mass to the carbon mass of stem was CA = 0,176197MB1,05, root carbon mass to the carbon mass of branches was CA = 11,74897MC0,418, root carbon mass to the carbon mass of twigs was CA = 1,706082MR1,08, root carbon mass to the carbon mass of leaves was CA = 1,261827MD1,33. Meanwhile, the model of estimation of root carbon mass to the mass of above ground trees was CA = 0,103038MT1,07 Root to shoot ratios of A. mangium tree biomass to the above ground biomass of trees were the followings; (a) root to shoot ratio of tree root biomass to the biomass of tree stem was 0,2934. (b) root to shoot ratio of tree root biomass to the biomass of all tree parts was 0.2080.Root to shoot ratios of carbon mass of A. mangium were as follows: (a) root to shoot ratio of carbon mass of tree root to the carbon mass of tree stem was 0.2437. (b) root to shoot ratio of carbon mass of tree root to the carbon mass of all above ground tree parts was 0.1952.
Keyword: 

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