Judul: Analisis Efisiensi Teknis dan Pendapatan Usahatani Talas di Kecamatan Kemang, Kabupaten Bogor
Abstrak: Kecamatan Kemang merupakan salah satu sentra produksi talas di Kabupaten Bogor, akan tetapi terdapat permasalahan yang dihadapi oleh petani dari sisi input produksi sehingga produksi belum maksimal. Penelitian ini bertujuan untuk 1) mengidentifikasi faktor-faktor yang memengaruhi produktivitas, 2) menganalisis efisiensi teknis, 3) menganalisis pendapatan usahatani talas di Kecamatan Kemang, Kabupaten Bogor. Penelitian ini menggunakan fungsi produksi Frontier Cobb-Douglas dengan metode Maximum Likelihood Estimation (MLE) untuk mengetahui faktor-faktor yang memengaruhi produktivitas, Stochastic Frontier Analysis (SFA) untuk mengetahui efisiensi teknis, dan analisis R/C Ratio untuk mengetahui keuntungan usahatani talas. Hasil penelitian menunjukkan bahwa faktor-faktor yang berpengaruh signifikan terhadap produktivitas usahatani talas adalah pupuk kandang dan tenaga kerja. Rata-rata efisiensi teknis sebesar 0,71 yang artinya usahatani talas sudah efisien. Faktor-faktor yang berpengaruh signifikan terhadap inefisiensi teknis yaitu pengalaman usahatani, dummy status pekerjaan, dan dummy pengelolaan lahan. Nilai R/C Ratio menunjukkan bahwa usahatani talas di Kecamatan Kemang dapat memberikan keuntungan., Kemang District is one of the centers of taro production in Bogor Regency, but there will be problems faced by farmers from the production side so that production is not maximized. This research aims to (1) identify the factors that affect the productivity (2) analyze the technical efficiency, (3) analyze the income of taro farming in Kemang District, Bogor Regency. This research uses the Frontier Cobb-Douglas production function with the Maximum Likelihood Estimation (MLE) method to determine the factors that affect the productivity, Stochastic Frontier Analysis (SFA) to determine the technical efficiency, and analysis of the R/C Ratio to determine the benefits of taro farming. The results showed that the factors that had a significant effect on the productivity of taro farming are manure and labor. The average of the technical efficiency of taro farming is 0.71, which means that taro farming is efficient. Factors that have a significant effect on technical inefficiency are farming experience, employment status dummy, and land management dummy. The R/C Ratio value shows that taro farming in Kemang District can provide benefits.
Keyword: Technical Efficiency, Productivity, R/C Ratio, Stochastic Frontier Analysis

Judul: Analisis preferensi risiko dan efisiensi teknis usahatani talas di Kota Bogor
Abstrak: Risk preferences play an important role in farmer’s decisions on input allocation and hence in output supply. Talas productivity in Bogor City was low that it was influenced by risk preferences of farmer. The objectives of this study were to analyze: (1) technical efficiency of talas farming in Bogor City, (2) talas farming technical inefficiency sources in Bogor City, (3) risk preferences of farmer in the face of talas farming production risk in Bogor City, and (4) the effect of risk preferences of farmer to talas farming technical efficiency in Bogor City. Frontier production function model with heteroskedastic error structure estimated by Maximum Likelihood estimation developed by Kumbhakar was adopted to analyze risk preferences of farmer and technical efficiency of talas farming in Bogor City. Sixty five samples were drawn by simple random sampling method. The results show talas farming are technically efficient, and farmer socio-economic characteristics such as land holding and age influence talas farming technical inefficiency sources in Bogor City. All farmers are risk taker that influences input allocation and technical efficiency. Result shows risk taker farmers used input higher that yield high technical efficiency and high productivity.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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