Judul: Perkiraan Biaya Perangkat Lunak dengan Jaringan Saraf Tiruan Propagasi Balik
Abstrak: In line with the advance of technology, human needs for software are also growing. Software is used to help people to lighten their work. This has caused the software becomes increasingly complex and the production cost also become increasingly expensive. No wonder if the software developers need a method of cost estimation that estimates accurately for the efficiency and effectiveness of the company. With this, the company can be protected from loss due to incorrect cost estimates. This study uses data from the COCOMO 81 derived from the Boehm journals in 1981, entitled Software engineering economics. This data group consists of 63 projects each have 17 main attributes, namely, a numerical type of 15 Cost Driver (CD), the size of the project in Kilo Lines of Code (KLOC), and the actual cost of the project in the Person of the Month (PM). Data are grouped into two parts, namely training data and test data in the form of 15 types of Cost Drivers and the size of the project (KLOC), this data is transformed into the range [0.1, 0.9] according to the sigmoid function of range. In this research, the neural network is used to do the software cost estimation. The network architecture used was the multilayer perceptron with a back propagation learning algorithm. The number of neuron in the hidden layer is determined from the optimal architecture which provides a best estimation value. Once found the best architecture which is has the optimal number of neuron, conducted the evaluation. The evaluation method used is the Mean Magnitude Error (MRE) and Pred (l). MRE is the error between the actual and estimated value while Pred (l) is prediction at the level L. Results of research indicate that there are relation between the types of project with the MRE. There is a tendency for this technique provides a high accuracy if the actual value of the test data is big. Poor accuracy obtained at the small value of actual test data. This research resulted in the value of Mean MRE (MMRE) of 76%, Median MRE (MRE Med) of 23% and Pred (0.25) of 52%. On this research, normalization of the target data has not been conducted so that the error generated in the process of evaluation is big.
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Judul: Software development effort estimation using fuzzy – intermediate COCOMO
Abstrak: Memprediksi biaya (atau usaha) pengembangan perangkat lunak adalah bagian yang paling menantang dalam proyek pengembangan perangkat lunak. Keberhasilan proyek dapat diprediksi sebelumnya baik dari perencanaan dan proses penjadwalan. Prediksi diukur dalam istilah person month yang diperlukan untuk mengembangkan proyek. Penelitian ini menggunakan logika fuzzy dan Constructive Cost Model (COCOMO) model dengan tiga variasi fungsi keanggotaan (MF), yaitu trapesium (MF1), berbentuk lonceng (MF2), dan kombinasi trapesium dan berbentuk lonceng (MF3). Data set yang digunakan dikumpulkan dari NASA yang terdiri atas 102 proyek dari tahun 1971 sampai 1990. Beberapa ukuran evaluasi yang digunakan adalah Mean Magnitude of Relative Error (MMRE) dan Magnitude of Relative Error (MRE) untuk mengukur keakuratan prediksi. Percobaan ini menghasilkan MMRE untuk MF1 65,51%, 92,74% MF2, dan MF3 163,36%. Meskipun MF2 memiliki MRE terkecil, yaitu, 0%, MF1 memiliki akurasi terbaik.
Keyword: perkiraan usaha perangkat lunak, COCOMO, logika fuzzy, fungsi keanggotaan

Judul: Isolasi senyawa golongan flavonoid sebagai antioksidan dari daun dandang gendis (Clinacanthus nutans)
Abstrak: The leaves of dandang gendis (Clinacanthus nutans) exhibit antioxidant activity. The objective of this study is to investigate the highest antioxidant activity from flavonoid extract of the leaves. Antioxidant activities were determined by radical scavenging assay using 1,1-diphenyl-1-pycryl-hydrazyl radical. The result showed that ethyl acetate extract had antioxidant activity with IC50 value of 178.40 mg L-1. The ethyl acetate extract was fractionated further using preparative thin layer chromatography with eluent of n-buthanol:acetic acid: water (4:1:5) and produced 3 fractions. The most active fraction was fraction 2 with IC50 value of 52.93 mg L-1, which was lower than that of butylated hydroxy toluene (IC50 16.71 mg L-1). Flavonoid assay of fraction 2 showed that it contained flavonol and flavon. The ultraviolet-visible spectrum of fraction 2 in methanol solvent showed a maximum absorption at 332 in band 1 and 274 nm in band 2. In MeOH+MeONa and MeOH+AlCl3-HCl solvents there was a bathochromic shift, indicated the presence of 4'-OH and 5-OH. The new peak at 326.5 nm showed the presence of 7-OH substituent.
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