| Penulis | Artikel | Abstrak |
|---|---|---|
| J. Tri Astuti, Lies Sriwuryandari, Retno Yusiasih, and T. Sembiring | GROWTH RESPONSE OF NANNOCHLOROPSIS AT OUTDOOR CULTIVATION IN MEDIUM WITH VARIATION OF NITROGEN CONCENTRATION | Micro-algae are fast-growing unicellular photosynthetic microorganisms that able to fi x CO2 while capturing solar energy. Source and concentration of nitrogen itself affected to the growth character and composition of microalgae. Cultivation with limited of nitrogen resulted great increase in the lipid content. This study was conducted to investigate the infl uence of nitrogen concentration to the growth rate and lipid characteristics of Nannochloropsis sp. In this study, ammonium nitrate (NH4NO3) was added in different concentration, i.e. 0; 30; 70; and 100% based on nitrogen content in f/2 medium, or equivalent to 0; 1.06; 2.47; and 3.53 (10-4 M). All treatment was prepared triplicate, then cultivated at outdoor batch culture systems and aerated continuously with a sterilized of atmospheric air. The algae biomass was harvested at 14th day after inoculated and then analyzed. Data showed that Nannochloropsis sp. could be cultivated in the outdoor batch system, which temperature was in the range of 26.11–37.97oC, with average of 33.44oC. Compared to its initial condition, pH culture increased signifi cantly from 6.92 to 8.54. The highest OD680nm (0.500) and dry cell concentration (458mg.L-1) was obtained by using NH4NO3 at 2.47x10-4 M. The lipid content was 63.58% and 46.59% of dry cell weight when using nitrogen 1.06x 10-4M and 2.47x10-4M, respectively. Composition of fatty acid was not signifi cantly affected by the changing of nitrogen concentration. Palmitic acid (C16:0) was the most of fatty acid in Nannochloropsis sp. (44.47–53.97%), followed by lauric acid (25.78–34.34%), and myrictic acid (19.07–21.19%). The using of N-NH4NO3 at 2.47x10-4M gave the highest lipid content of 213.15mg.L-1. |
| P. Sebayang, Muljadi, Masno Ginting, dan Henry | PEMBUATAN KERAMIK GERABAH BERBASIS LIMBAH PADAT DARI INDUSTRI PULP DAN TANAH LIAT | Telah dilakukan pembuatan keramik gerabah berbasis limbah padat dari industri pulp (sludge) dan tanah liat dengan berbagai variasi komposisi (dalam persentase massa). Preparasi bahan baku dilakukan dengan cara giling menggunakan ball mill selama 24 jam sehingga diperoleh serbuk yang lolos ayakan 100 mesh. Kemudian pada bahan tersebut dicampur dengan perekat Polivinylalcohol (PVA) sebanyak 50 ml, dan diaduk hingga rata. Pembentukan benda uji dengan cara cetak, tekanan sebesar 25 kgf/cm², dan dikeringkan dalam oven pada suhu 60°C selama 24 jam. Proses sintering menggunakan tungku listrik (heating rate sebesar 10°C/menit), saat mencapai suhu 900°C lalu ditahan selama dua jam. Dari hasil pembuatan keramik gerabah diperoleh komposisi optimum adalah 50% limbah padat dari industri pulp (sludge) dan 50% tanah liat dengan suhu sintering 900°C yang ditahan selama dua jam. Pada kondisi ini diperoleh nilai bulk density = 1,37 g/cm³, crystal density = 2,71 g/cm³, porositas = 39,26%, dan kuat tekan = 62,9 kgf/cm2. Hasil analisis XRD menunjukkan bahwa terdapat lima fase, masing-masing silicon oxide (SiO2), calcite (CaCO3), calsium oxide (CaO), magnesium silicate (MgSiO3) dan sillimanete (Al2SiO5). Calcite (CaCO3) merupakan fase dominan dan lainnya merupakan fase minor. Dari pengukuran dengan SEM diketahui bahwa bentuk partikel yang dihasilkan tidak beraturan dengan ukurannya lebih kecil dari 5 μm, dan ukuran pori lebih kecil 1 μm. |
| Lies Sriwuryandari, T. Sembiring | LIQUID BIOFERTILIZER AND COMPOST FROM ORGANIC MARKET WASTE | Liquid biofertilizer and compost from organic market waste were produce by the addition of some functional microorganisms. Azospirrillium sp., Azotobacter sp., Lactobacillus sp., Pseudomonas sp. and Actinomycetes were inoculated into liquid or solid raw materials. The ripe biofertilizer were characterized and meets the Indonesian National standards for biofertilizer. Actinomycetes contained in the liquid fertilizer about 2.95 x 108 cfu/ml, which is meet the standard (≥ 104 cfu/ml) and other functional microorganisms namely Lactobacillus sp., Azospirillium sp., Azotobacter sp., Pseudomonas sp. and phosphate diluters were grown enormously with the population of more than 105 cfu/ml respectively. Qualitative test of the fertilizer shown that the fertilizer are effective for the crops such as Long bean (Vigna unguiculata), Cucumber (Cucumis sativus), Leek (Allium ampeloprassum) and others. Production of biofertilizer using organic market waste support the organic farming and the national policy on the fertilizer |
| Dody Priadi | APLIKASI TEKNIK ENKAPSULASI PADA BENIH SENGON (Paraserianthes falcataria) | Seeds were encapsulated using materials containing nutrients in order to survive on a deforested land after spreading by aeroseeding technique. Sengon (Paraserianthes falcataria) seeds from Bogor, Tasikmalaya and Garut were encapsulated using mixture of soil, rice bran, tapioca fl our with compost made from leaf waste and manure (3:1) as a nutrients source. Seeds with a good appearance were tested for the moisture content and stratifi ed prior to germination test on tissue paper and grassy and sandy soil to determine the initial germination. Results of initial seeds germination showed that the highest germination (61.7%) on grassy soil obtained by the seeds from Cianjur, while the lowest (39.0%) obtained by seeds germinated on sandy soil. Seed stratifi cation prior to germination causes the capsule damage and early germination. Encapsulated seeds failed to germinate in germination chamber although the capsules already broken. The highest germination percentage (24.7%) and plant height (3.9 cm) obtained from the encapsulated seeds containing media G (100 g soil + 100 g compost + 100 g tapioca fl our) with the exception for total compound leaves and roots. Seeds encapsulated using rice bran causes microbial contamination of seed capsules so that failed to germinate. This study showed that the tapioca fl our was absolutely necessary as an adhesive agent within encapsulate components with seeds, while the compost can enhance plant growth. Contrary the rice bran causes microbial contamination on seed capsules. |
| Wuwus Ardiatna, Dwi Mandaris, Dini Andiani, dan R. Harry Arjadi | PENGUKURAN TINGKAT EMISI RADIASI ELEKTROMAGNETIK KERETA REL LISTRIK TERHADAP LINGKUNGANNYA | The amount of voltage that is used to run Electric Drive Train (Kereta Rel Listrik–KRL) system simultaneously resulted on the electromagnetic fi eld radiation (EM). If the level of EM radiation exceeded the threshold of specifi ed standard, it will cause adverse effects to the environment. In this paper, measurements of EM radiation levels emitted by KRL (especially on Serpong-Tanah Abang) have been conducted. System and method of this measurement are based on the standard BS-EN 50121-2:2006. The results showed that the value of EM radiation levels generated by the KRL is below the threshold set by standard. The highest radiation levels occurred at frequency 936 MHz with fi eld strengths of 48.59 dB dBμV/m at horizontal antenna polarization. |
| Goib Wiranto, I Dewa Putu Hermida | PEMBUATAN SISTEM MONITORING KUALITAS AIR SECARA REAL TIME DAN APLIKASINYA DALAM PENGELOLAAN TAMBAK UDANG | Dalam tulisan ini akan dibahas rancang bangun sebuah sistem monitoring kualitas air yang dapat memberikan informasi secara real time tentang parameter kualitas air yang sedang diukur. Sistem yang dibuat memiliki komponen utama, yaitu sebuah data logger yang memiliki fi tur sms gateway berbasis jaringan GSM, dan dua komponen sensor yang digunakan untuk mengukur parameter DO dan pH. Selain menampilkan hasil pengukuran secara onsite, sistem ini juga mampu memberikan informasi melalui HP bila nilai ambang DO atau pH terlampaui. Sebaliknya, nilai DO dan pH hasil pengukuran bisa juga diketahui setiap saat melalui sms dari HP ke sistem. Sistem ini telah diaplikasikan untuk memantau kualitas air tambak udang di daerah Banyuwangi, Jawa Timur. Selain memberikan informasi secara real time, sistem juga dapat secara otomatis menggerakkan kincir-kincir air di tambak bila nilai DO turun di bawah ambang batas. Dengan begitu, kebutuhan oksigen untuk budi daya udang dapat selalu terjaga. |
| Demi Soetraprawata, Arjon Turnip | NEURAL NETWORK TRAINING USING SEQUENTIAL EXTENDED KALMAN FILTER FOR RELIABLE ROAD FRICTION COEFFICIENT ESTIMATION | The aim of this study is to estimate the vehicle dynamic parameters concerning with road safety (such as, road tire forces, longitudinal and lateral velocities, angular velocity, rolling radius of wheels, side slip, pitch and roll angle, and road friction coeffi cient which are diffi cult to be measured directly in a standard car) using neural network training on the basis of sequential extended Kalman fi lter (SEKF) and the recursive least squares (RLS). For such estimation, a fourteen degree-of-freedom (DOF) nonlinear full-vehicle dynamics model was developed to provide the simulation requirement. The simulation was performed and compared with CarSim (the interpreter for vehicle dynamics) to verify the model, which confi rms the expected results were all the state variables follow the CarSim response well. The simulation results show that the system performs reliably and fastly in estimating the parameters on different road surfaces during various vehicle manoeuvres. |
| Andria Arisal | DISTRIBUTED CONSTRAINTS SATISFACTION FOR MULTI AGENT SYSTEM | Sistem multi agen (multi agent system) biasanya harus menyelesaikan persoalan-persoalan dengan batasan yang spesifi k, yang tidak jarang sangat ketat. Untuk itu, sistem multi agen harus dapat memanfaatkan agen-agen yang ada dengan pengetahuan mereka tentang batasan yang terbatas. Untuk menghadapi persoalan ini, kami menggunakan suatu algoritma untuk persoalan pemenuhan batas antardistribusi, yaitu asynchronous incremental relaxation dalam ranah kasus extreme kitchen. Algoritma ini menggunakan jejak balik multi nilai (multi value backtrack) dengan nilai ambang yang sudah terbukti dapat menyelesaikan persoalan yang sangat ketat, dengan mengusulkan tujuan yang paling sedikit melanggar batasan yang ditetapkan |
Penulis : J. Tri Astuti, Lies Sriwuryandari, Retno Yusiasih, T. Sembiring, P. Sebayang, Muljadi, Masno Ginting, Henry,
Lies Sriwuryandari , Dody Priadi, Wuwus Ardiatna, Dwi Mandaris, Dini Andiani, dan R. Harry Arjadi, Goib Wiranto, I Dewa Putu Hermida, Demi Soetraprawata, Arjon Turnip
Andria Arisal
Dewan redaksi : Tarzan Sembiring, Moch Ichwan, Dyah Hardini, Goib Wiranto, Adiseno, Tigor Nauli, Elan Djaelani, Linar Z Udin, Adrin Tohari, Fauzan A, Fatimah ZS Padmadinata, Masno Ginting, Rudi Subagja, Sarwintyas Prahastuti, Siti Kania Kushadiani, Nanik Supriyanti, Euis Setiawati, Junaedi Mulawardana
ISSN : 0126-1533
Tahun Penerbitan : 2011
Penerbit : LIPI PRESS
