Judul: Pemodelan Harmonik Tinggi pada Kristal Zincblende (GaAs) untuk Sembarang Polarisasi Masukan Menggunakan Model Ikat Hiperpolarisabilitas
Abstrak: Gallium arsenide (GaAs) merupakan semikonduktor golongan III-V dengan susunan kristal non-centrosymmetric, mengakibatkan kontribusi dipol dari permukaan dan dari dalam bulk pada harmonik tinggi tidak sama dengan nol. Tujuan dari penelitian ini adalah memodelkan respons harmonik tinggi dan membandingkan intensitas radiasi harmonik kedua dan ketiga pada kristal Zincblende (GaAs) untuk sembarang polarisasi masukan. Pemodelan menggunakan model ikat hiperpolarisabilitas dengan mendefinisikan arah ikatan atom yaitu ikatan atom yang arahnya ke atas dan ke bawah. Dirotasi pada sumbu azimuth untuk mendapatkan tensor suseptibilitas. Tensor suseptibilitas didotkan dengan medan listrik masukan dan menghasilkan polarisasi yang selanjutnya didapatkan far-field. Harmonik kedua atau SHG terdapat 4 puncak simetri yang bernilai nol setiap kelipatan 900. Sedangkan pada harmonik ketiga atau THG terdapat perubahan banyak puncak intensitas dari 8 puncak simetri menjadi 4 puncak simetri. Pemodelan memperlihatkan bahwa intensitas radiasi harmonik ketiga lebih kecil dari intensitas harmonik kedua.
Keyword: GaAs, harmonik tinggi, model ikat hiperpolarisabilitas, optika nonlinier

Judul: Pemodelan Harmonik Tinggi pada Kristal Diamond dengan Sembarang Polarisasi Gelombang Masukan
Abstrak: Karakterisasi bahan sentrosimetris menggunakan optika nonlinier memiliki keunggulan. Salah satu keuntungan untuk membangun teori analisis permukaan. Tujuan penelitian ini untuk memodelkan harmonik tinggi pada kristal diamond dengan sembarang polarisasi gelombang masukan menggunakan Simplified Bond Hyperpolarizability Model (SBHM). Interaksi antara bahan dan medan listrik dari luar mengakibatkan muatan akan berosilasi secara anharmonik sepanjang ikatan dan meradiasikan gelombang dipol yang dapat di ukur pada Far Field. Dalam penelitian ini, kita menemukan bahwa intensitas generasi harmonik kedua dan ketiga pada bahan sentrosimetrik seperti Si (111) di simulasikan dengan sembarang polarisasi gelombang masukan menggunakan SBHM. Hasil penelitian ini memperlihatkan bahwa polarisasi s – input,p – output dan p – in, p – out pada penelitian ini sesuai dengan hasil data intensitas eksperimen.
Keyword: optika linier, hiperpolarisabilitas, harmonik tinggi, polarisasi

Judul: Biology and ecology of the buffalo fly, haematobia exigua de meijere (diptera:muscidae)
Abstrak: The life history of the buffalo fly was observed at room temperature of 27°-29.5°C and at a relative humidity of 48-68 percent. The eggs hatched after 17-22 hours, with an average of 18 hours. First instar larvae measured 1.25 + 0.16 mm long and 0.27 + 0.037 mm wide. reach the second larval stage. It took 6-12 hours to the second instar larvae measured 2.676 +0.187 mm long and 0.353 +0.028 mm wide. The second instar took about 12-24 hours to reach the third larval stage. The third instar measured 6.833 + 0.189 mm long and 0.919 + 0.051 mm wide. It took about 2-3 days for the third instar to become pupae. Duration of the pupal stage was about 5-7 days before the adults emerged. Under laboratory condition, the buffalo fly completed its life cycle in 9.5 to 10.5 days, whereas under field condition it took 9-14 days with an average of 10.5 days. The growth ratio which was based on the measurements of the cephalo-pharyngeal skeleton of each instar was 1.797. The preoviposition period was 8-12 days and mating usually occurred on the 6th or 7th day. The longevity of the male was 29 days, whereas it was 32 days in the female. The range of egg production under laboratory condition was between 20-139 per female fly. The belly and hind legs of the carabao were the most preferred habitat either during cloudy and cool dry or shiny and warm day. When the weather was clear and the carabao was in the shade, the flies tended to be more distributed particularly on the shoulder, dewlap, back and horns. The carabaos had relatively fewer Musca sp. and Stomoxys calcitrans than cattle; never the less carabaos had a higher infestation of buffalo fly than cattle. Oviposition occured either during the day or night but the buffalo flies were more active during the night than in the day time. The effect of various lengths of exposure time of manure in relation to the oviposition was profound. observed, the maximum number of the buffalo flies was occurred when the dung was exposed for 30 minutes. With increasing time of exposure the number and variety of insects also increase. It was evident that Sepsidae and psychodidae were the most dominant insects emerging from the dung. The number of buffalo flies also increased with increasing
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