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: Greenhouse Gas Emissions from Beef Cattle  Manure in Semangke Hamlet, Jenu District, Tuban Regency
Abstrak: Emisi gas rumah kaca (GRK) merupakan salah satu penyebab utama perubahan iklim. Peternakan, dengan kontribusi besar terhadap emisi GRK seperti CO2, CH4 dan N2O, turut berperan dalam masalah ini. Penelitian ini fokus pada emisi metana (CH4) yang dihasilkan oleh peternakan sapi potong di Dusun Semangke, Kecamatan Jenu. Menggunakan metode IPCC AFOLU Tier-2, total populasi ternak sebanyak 32,05 satuan ternak di Dusun Semangke diperkirakan dapat menghasilkan emisi GRK sebesar 23,00 Gg CO2-e tahun-1 . Emisi tersebut terdiri dari tiga komponen utama: fermentasi methan fermentasi entirik sebesar 22,31 Gg CO2-e tahun-1 , emisi methane dari pengelolaan ternak sebesar 0,67 Gg CO2-e tahun-1 , dan emisi N2O dari pengelolaan kotoran sebesar 0,02 Gg CO2-e tahun-1 , Meskipun demikian, sektor pertanian di Dusun Semangke memiliki kapasitas penyerapan karbon sebesar 1239,50 Gg CO2-e tahun-1 , yang melebihi emisi yang dihasilkan dari populasi ternaknya. Bersasarkan surplus serapan karbon sebesar 1216,50 Gg CO2-e tahun-1 , dapat disimpulkan bahwa kondisi ini bisa terus ditingkatkan melalui program mitigasi seperti manajemen pakan, pengelolaan kotoran dan penanaman hijauan pakan., Greenhouse gas (GHG) emissions are one of the main drivers of climate change. With significant contributions to GHG emissions such as CO2, CH4, and N2O, livestock play a role in this issue. This study focused on methane (CH4) emissions from beef cattle farming in Semangke Hamlet, Jenu Sub-district. Using the IPCC AFOLU Tier-2 method, the total livestock population of 32,05 livestock units in Semangke Hamlet emitted 23,00 Gg CO2-e year-1 of GHGs. These emissions consisted of three main components: enteric fermentation methane emissions of 22,31 Gg CO2-e year-1 , methane emissions from livestock management of 0,67 Gg CO2-e year-1 , and N2O emissions from manure management of 0,02 Gg CO2-e year-1 . Despite this, the agricultural sector in Semangke Hamlet has a carbon sequestration capacity of 1239,50 Gg CO2-e year-1 , which exceeds the emissions generated by its livestock population. With a carbon sequestration surplus of 1216,50 Gg CO2-e year-1 , it can be concluded that this condition can be further improved through mitigation programs such as feed management, manure management, and forage planting.
Keyword: beef cattle, IPCC, greenhouse gas, Tier 2

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