Judul: The study potention of emission greenhouse gas reduction in slaughter house (Case Study : Slaughter House Of Pt Elders Indonesia, Bogor)
Abstrak: Slaughter house is one of the livestock industries that generate emissions of greenhouse gases from activities of their production, one of the emission gases is methane gas. Eco-efficiency in the slaughter house is a business strategy in the production of cattle through the use of less energy and reduce livestock methane simultaneously. Reducing greenhouse gas emission its doing by calculate the emissions from activity data and factor emission, with units of carbon dioxide equivalent, and collect the others data that could support the determination of emission reduction options. Greenhouse gas emissions on slaughter house resulted by electricity, generators, and LPG (Liquefied Petroleum Gases), as well as wastewater treatment and solid waste. The percentage of greenhouse gas by slaughter house with capacity ± 900 cattle per month, are 98,2% from waste treatment and 1,8% from energy consumption. The recommended options can be given to reducing greenhouse gas emissions are the use of solid and liquid waste to replace the gas consumption with biogas, the use of solid waste for composting process, efficiency use of lighting, and efficiency use of production machinery. The most potentially option for reduce the greenhouse gas emissions are use of solid and liquid waste for biogas which the reduce percentage amount of ± 69% and use of solid waste for composting process which the reduce percentage amount of ± 80,3%.
Keyword: 

Judul: Pendugaan emisi gas metan dan dinitrogen oksida dari berbagai jenis ternak di Kabupaten Bogor
Abstrak: The aim of these research was to observe the level of emission greenhouse gases from livestock sector in Bogor Regency. Various animal species used in this research were dairy cow, beef cattle, buffalo, swine, horse, and poultry. Data of livestock’s population in Bogor Regency were used for basic calculation. The data were collected from literature and direct observation collection through survey of animal characterization and manure management, inventory equation of emission greenhouse gas based on Intergovernmental Protocol of Climate Change (IPCC). Data were processed by Microsoft Excel. Model of calculation consist of model I and model II. Model I used IPCC default data, meanwhile model II used literature and survey data. Methane and dinitrogen oxide which was produce from livestock converted into carbon dioxide based on value of Global Warming Potential (GWP). The greenhouse gases emission in Bogor Regency were 201.46 Gg CO2 eq by model I and 170.21 Gg CO2 eq by model II. Animal which was produced GHG from the highest to the lowest by (model I and model II) were sheep (33% and 39%), dairy cow (21% and 9%), buffalo (16% and 18%), goat (12% and 17%), beef cattle (10%), poultry (6% and 7%), swine (1% and 0%), and horse (0%). The highest level of greenhouse gases emission was produced by Pamijahan District as many as 17.63 Gg CO2 eq (8.75%) by model I and 12.1 Gg CO2 eq (7.03%) by model II.
Keyword: 

Judul: Analisis Kestabilan Model Virus Komputer dengan Infeksi Tunda dan Pemulihan Tunda.
Abstrak: In this paper, a dynamical model is composed of computer virus model that considers time delay of infection and recovery processes. Stability analysis is performed to both models, i.e. the models with and without time delay. The model without time delay has two fixed points, which one of them is stable and the other is unstable. On the other hand, the model with time delay has fixed points which one of them is spiral stable. If the value of time delay is sufficiently large, then it will imply the stability changes from spiral stable to spiral unstable and subsequently the appearance of limit-cycle and Hopf bifurcation.
Keyword: computer virus model, Hopf bifurcation, time delay