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This study aimed to investigate the chemical constituents from Alphonsea cylindrica as well as their cytotoxic and xanthine oxidase inhibitory activities. The chemical compounds were isolated and purified by various chromatographic techniques and their structures were elucidated via modern spectroscopic techniques including NMR, MS, IR, UV and comparison with literature. A study on the barks of A. cylindrica has found eleven known compounds were identified as stigmasterol (1), isoursuline (2), cyathocaline (3), kinabaline (4), muniranine (5), isooncodine (6), iraqiine (7), Omethylmoschatoline (8), kareemine (9), atherospermidine (10) and N-methylouregidione (11). The cytotoxic effect of hexane, DCM and methanol of bark of A. cylindrica as well as the isolated compounds; 1, 2, 3, 4, 5, 7, 8, 9 and 10 were estimated on MCF-7 human breast cancer cells and isoursuline possessed the most potent inhibitory activity with IC value of 33 µg/ml. Eight compounds 1, 3, 4, 5, 6, 8, 10 and 11 displayed moderate inhibitory activity effect with IC < 100 μM against xanthine oxidase. As a conclusion, eleven compounds have been isolated from the bark of A. cylindrica King. Some of the compounds also showed potential against cytotoxicity and xanthine oxidase inhibitory activities. The findings of this study can enhance the understanding of the chemotaxonomy aspect of the A. cylindrica as well as its potential in traditional and modern medicine.

Over recent years, there has been an explosive growth of interest in Electroencephalogram (EEG) based-Brain Computer Interface (BCI). Technically any architecture of a BCI is designed to have the ability of extracting out a set of features from brain signal. This paper demonstrated the extraction process based on Probability Density Function (PDF).A shared control scheme was developed between a mobile robot and subject. In general, subjects were required to synchronously imagine a star rotating and mind relaxation at specific time and direction. The imagination of a star would trigger a mobile robot suggesting that there is an object at certain direction. The mobile robot was then looking for a target based on probability value assigned to it. The result shows that 95% of theta activity was concentrated at target’s direction (during star imagination) and reduced when there is no target (during mind relaxation).

Planting seeds may be trivial and can be done manually. However, on a large scale, it will inevitably become time-consuming and labor intensive. The use of robot can be an alternative solution to improve the efficiency of this agricultural-related work so that farmers can focus more on the decision making perspective rather than the labor-intensive works. This study aims to develop a prototype of a task-oriented seed-planter robot that can be used to assist farmers. The robot has three wheels: two motorized wheels and one free-wheel for its stability. It is equipped and programmed with line follower sensors and algorithm to simplify its navigation procedure, by assuming that the field is already marked before plantation process. The main contribution of this study is the design of the actuators of the robot prototype which enables the robot prototype to dig a hole, plant the seed and then close the hole again.

Saat ini sistem kendali yang populer digunakan pada quadcopter adalah kendali proportional, integral, derivate (PID) karena algoritme tersebut sederhana. Namun pada implementasinya, PID membutuhkan penyetelan parameter yang memakan waktu dan rentan terhadap kesalahan. Oleh karena itu, sistem kendali jaringan saraf tiruan propagasi balik untuk quadcopter saat ini mulai banyak dikembangkan karena menawarkan stabilisasi yang lebih baik dari faktor-faktor yang tidak diketahui dan data sensor yang mengandung noise. Akan tetapi, sistem kendali jaringan saraf tiruan propagasi balik memerlukan data latih yang akurat dan dapat mewakili seluruh kemungkinan kondisi terbang quadcopter. Penelitian ini bertujuan untuk memperoleh data terbang quadcopter dari data log sensor dan aktuator yang ada di quadcopter, yaitu giroskop, akselerometer, magnetometer, barometer, GPS, dan pulse width modulation output. Pengambilan data dilakukan dengan menerbangkan quadcopter secara otomatis dengan koordinat awal dan akhir yang telah ditentukan untuk mengisi data log terbang. Data log terbang diambil menggunakan perangkat lunak Mission Planner. Data log akan dipraproses untuk kemudian dilakukan sinkronisasi time sampling. Sinkronisasi dilakukan dengan mengikuti data sensor yang time sampling-nya paling besar. Hasil dari penelitian ini adalah data terbang dari sensor dan pulse width modulation output quadcopter yang telah disinkronisasi untuk menjadi data latih jaringan saraf tiruan propagasi balik. Kata Kunci: data terbang quadcopter, jaringan saraf tiruan propagasi balik, quadcopter, sistem kendali