Judul: Pendekatan Model Fuzzy untuk Pendugaan Bobot Badan Kerbau Lumpur Berdasarkan Lingkar Dada dan Panjang Badan
Abstrak: Body weight of a swamp buffalo can be determined by measuring the buffalo weight directly or indirectly. Measuring the buffalo weight directly is relatively difficult. Measuring the weight indirectly can be performed using a conventional formula or fuzzy model. In this paper, a fuzzy model is used to estimate the body weight of a swamp buffalo, then the result is compared with the result of calculation using four conventional formulas. There are some steps being taken on deriving the fuzzy model, namely fuzzification, application of implication function, composition of rules, and defuzzification. Inputs used in this fuzzy model are the chest circumference and the body length. The output of this model is the body weight. The accuracy of estimation based on conventional formula and fuzzy model is compared by using mean absolute percentage error (MAPE). Based on the value of MAPE, it can be concluded that the fuzzy model is relatively better than the first three of conventional formulas, but it is not better than the fourth formula.
Keyword: MAPE, fuzzy model, swamp buffalo

Judul: Estimasi Bobot Badan berdasarkan Ukuran Tubuh pada Sapi Madura yang Dipelihara secara Intensif
Abstrak: Bobot badan menjadi parameter penting dalam manajemen pembibitan, namun pengukurannya sulit dilakukan karena keterbatasan fasilitas timbangan. Tujuan dari penelitian ini adalah menganalisa hubungan antara variabel antara ukuran linier tubuh dan bobot badan pada sapi madura dengan sistem pemeliharaan intensif. Penelitian ini menggunakan 85 sampel data morfometrik, seperti panjang badan, lingkar dada, tinggi pundak, dan bobot badan yang dikategorikan berdasarkan umur dan jenis kelamin lalu dianalisis dengan metode bivariat Pearson dan regresi linier sederhana. Analisis data dilakukan secara berurutan dari analisis deskriptif hingga uji signifikansi pada taraf 5%. Hasil penelitian menunjukkan bahwa nilai koefisien korelasi dan determinasi tertinggi serta nilai RMSE terendah dari persamaan regresi terdapat pada hubungan variabel lingkar dada dengan bobot badan pada setiap kategori. Salah satu contoh persamaan regresi pada hubungan variabel lingkar dada dengan bobot badan pada sapi madura jantan 205 hari adalah Y=-163,333+2,431X dengan nilai RMSE, R2, dan r masing-masing 2,092, 0,976, dan 0,988, serta memiliki hubungan yang signifikan. Oleh karena itu, variabel lingkar dada dapat digunakan untuk estimasi bobot badan pada sapi madura., Body weight is an important parameter in breeding management, but its measurement is difficult due to limited weighing facilities. This study aims to analyze the correlation between variables between linear body size and body weight in madura cattle cared under intensive rearing system. This study used 85 samples of morphometric data, such as body length, chest girth, wither height, and body weight which categorized based on age and sex, and then analyzed using the Bivariate Pearson method and simple linear regression. The analysis was carried out sequentially from descriptive analysis to significance test at the 5% level. The results showed that the highest correlation and determination coefficient values and the lowest RMSE values from the regression equation were found in the correlation between chest girth and body weight in each category. An example of a regression equation on the correlation between chest girth and body weight in a 205-day-old madura calf is Y=-163,333+2,431X with RMSE, R2, and r values of 2.092, 0.976, and 0.988, and has a significant result. Therefore, the chest girth can be used to estimate body weight in madura cattle.
Keyword: body weight, madura cattle, morphometric, simple linear regression

Judul: Pembuatan Sel Fotoelektrokimia Padat dengan Struktur ITO/CdS/Elektrolit/ITO
Abstrak: photoelectrochemical solid cell in ITO/CdS/Electrolyte/ITO structure has been succesfully composed through this research. The photoelectrochemical cell material is a layer of cadmium sulfide deposited onto an ITO-covering glass substrate. The CdS layer is used as a working electrode of the cell. The solid electrolyte used is a combination of chitosan-PEG-KI/I2. The concentration of KI/I2 was varied from 0.1/0.01 M to 0.5/0.05 M. The current-voltage output of the cell was measured under a light illumination of a tungsten lamp and the sun. The output voltage found increases around 50% when the KI/I2 consentration was raised from 0.1/0.01 M to 0.5/0.05 M. When the radiation intensity increased from 1.074 mW/m2 to 4.147 mW/m2, Voc voltage increased around threefold, Isc current increased around twice, and power efficiency increased around twice at a fixed concentration. The highest efficiency of the solar cells (on singlecell measurements) obtained at the concentrations of 0.5/0.05 M KI/I2. In a circuit consist of 4 solar cells, the highest power eficiency and FF produced by the serial circuit.
Keyword: