Judul: Sistem Pemetaan Daerah Penangkapan Ikan Cakalang (Katsuwonus pelamis) di Perairan Prigi Jawa Timur
Abstrak: Prigi waters locates in the south of East Java is one of the potential fishing grounds in Indonesia which the main commodities are skipjack and tuna. These waters are a strategic place for trolling fishermen and either local purse seine fishermen nor fishermen who come from the outside of Prigi waters. In 2011, the production volume of tuna in Prigi fishing port is 717189 kg with production value to 6 761 309 850 IDR . In addition, the amount of fishing gear in 2011 is 86 units and purse seine is 159 units. Tuna fishing season is from June to October and peaking in August and September. But the welfare of fishermen, especially for fishermen trolling is under feasible because the benefits are low. The fishermen determine the skipjack fishing area systems with hunting and some have been using FADs and light as a tool to collect hordes. These devices are led to the arrest of a very high operating cost. Suspect in a fishing grounds skipjack in the waters of Indonesia, is already available in the form of map forecasting potential fishing grounds through the Marine Observation and Research Agency (MORA) which can be obtained free of charge on the internet. However, this facility has not been used by fishermen in Prigi because of the information displays is not match with the real conditions of fishing trolling in waters Prigi. Mapping system is a fishing area covers various aspects which increase a result of fisheries catches including tuna. These aspects include aspects of human resources, fish resources, fishing season, fishing gear technology and a fleet of fishing vessels. The objective of this study is to make the fishing grounds mapping system in Prigi Fishing Port, to evaluate the mapping systems that support skipjacks fishing grounds in the waters of Prigi and to make mapping of skipjack fishing ground in Prigi waters. Hopefully, through this research produces fishing grounds mapping system in accordance with the small-scale fisheries that can completes map forecasts that have been made by MORA. The result of the map of skipjack fishing grounds in Prigi waters which analyze with the mapping system will also be applied in other grounds of Indonesia with an adjustment to the character of each region. This study was conducted in three phases. The first phase of this study is field survey which the study was on last January 2012 in Prigi Fishing Port. The second phase is data collection of tuna catches and interviews with the fishermen from July to October 2012. The third stage is downloads the image of sea surface temperature (SST) and chlorophyll-a level 3 on the Aqua MODIS satellite which free from clouds cover and process data from the internet to get information and oceanographic parameters such as SST and chlorophyll-a which began in November 2012 to February 2013 in the Department of Utilization Fisheries Resources, Faculty of Fisheries and Marine Sciences (FFMS) Bogor Agricultural University (BAU). In addition to analyzing the catch, fish size, SST and daily chlorophyll-a, time series analyze was also carried out from January 2007
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Judul: Model of Skipjack Tuna’s (Katsuwonis pelamis) Fishing Area Using Generalized Additive Model (GAM) in Rumpon Area of Palabuhanratu Sea Waters, West Java
Abstrak: Ikan cakalang (Katsuwonis pelamis) menjadi salah satu target tangkapan karena memiliki nilai ekonomis yang tinggi. Nelayan di Palabuhanratu menggunakan rumpon yang dipasang di beberapa titik sehingga nelayan cenderung kembali pada titik yang sama untuk penangkapan. Penelitian bertujuan menganalisis daerah potensial penangkapan ikan cakalang menggunakan Generalized Additive Model (GAM) di lokasi rumpon Perairan Palabuhanratu. Lokasi penelitian di perairan Pelabuhan Ratu dan sekitarnya. Data yang digunakan adalah data tangkapan ikan yang diperoleh dari logbook dan data parameter oseanografi yaitu suhu permukaan laut (SPL) dan konsentrasi klorofil-a (Chl-a) estimasi dari satelit serta data salinitas dari pemodelan. Analisis spasial dengan GAM untuk menganalisis hubungan parameter oseanografi terhadap kelimpahan ikan dalam nilai Catch per Unit Effort (CPUE). Hasil analisis menunjukkan model yang paling baik untuk prediksi zona potensial penangkapan ikan berdasarkan validasi adalah kombinasi parameter SPL, Chl-a, dan salinitas dengan nilai signifikasi (p-value) untuk parameter SPL yaitu 0.0074, parameter Chl-a sebesar 0.3965, dan parameter salinitas sebesar 0.1699. Model memiliki nilai Akaike’s Information Criteria (AIC) sebesar 13.76 dan nilai Deviance Explained (DE) sebesar 60.2 %. Hasil model dan prediksi menunjukkan ikan cakalang cenderung berada pada kisaran nilai SPL sebesar 28 – 28.8 °C, nilai klorofil-a sebesar 0.16 - 0.49 mg/m3 dan nilai salinitas sebesar 33.88 - 34.19 psu., Skipjack tuna (Katsuwonis pelamis) is one of the catch targets because it has high economic value. Fishermen in Palabuhanratu use rumpon installed at several points so that fishermen tend to return to the same point for catching. The aim of the study was to analyze potential skipjack catching areas using the Generalized Additive Model (GAM) in rumpon area, Palabuhanratu Sea Waters. The research location is in the sea waters of Pelabuhan Ratu and its surroundings. The data used are fish catch data obtained from logbooks and oceanographic parameter data, namely sea surface temperature (SST) and chlorophyll-a concentration (Chl-a) estimates from satellites as well as salinity data from modeling. Spatial analysis with GAM to analyze the relationship of oceanographic parameters to the abundance of fish in the value of Catch per Unit Effort (CPUE). The results of the analysis show that the best model for predicting potential fishing zones based on validation is a combination of SST, Chl-a, and salinity parameters with a significance value (p-value) for SST parameters of 0.0074, Chl-a parameter of 0.3965, and salinity parameter of 0.1699. The model has Akaike's Information Criteria (AIC) value of 13.76 and Deviance Explained (DE) value of 60.2%. The results of the model and predictions showed that skipjack tuna tended to be in the range of SST values of 28 – 28.8 °C, chlorophyll-a values of 0.16 - 0.49 mg/m3 and salinity values of 33.88 - 34.19 psu.
Keyword: Generalized additive model, ikan cakalang, klorofil-a, salinitas, suhu permukaan laut, Chlorophyll-a, salinity, sea surface temperature, skipjack tuna

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model