Judul: Pengembangan Deskriptor Akustik Plankton di Teluk Ambon Bagian Dalam Menggunakan Echosounder Biosonic DT-X
Abstrak: Plankton is a very important organism in the food chain of the water coloum. The aim of this research is to analyze some of the physical parameters of waters that suspected influenced the acoustic parameters of plankton, to get acoustic parameter values from plankton by using split beam echosounder for quantification and identification plankton and developed an acoustic descriptors to identification and quantification activities community of plankton. The research was carried out in March 2012, located in Inner Ambon Bay waters, Ambon Island, Moluccas province, at the position of 128o12’792” - 128o12’ 792” BT and 3o38’795” - 3o38’874” LS. The depth of the waters at the site of the research are 25,17-27.00 meters with an average depth of 25,93 meters. Water temperature is 28,84 – 30,10oC with average 29,43oC where during the daytime is 29,37oC, and at night is 29,48oC. The salinity average of each measurement range between 33,53-33,62 PSU, where the salinity at the surface of sea water are 31,76- 32,67 PSU and at bottom the waters are 33,80-33,89 PSU. The density of water are 1.019,79-1.019,39 kg.m-3. Average of the waters turbidity every observation are 0,949-0,957 NTU with the highest value is 0,921 and at the lowest is 1,005 NTU. The community of phytoplankton found in research locations are 26 genus consists of 6 classes that are classified in the class Bacillariophyceae (4 genera), Ciliatea (2 genera), Coscinodiscophyceae (10 genera), Cyanophyceae (1 genus), Dynophyceae (6 genera) and Fragilariophyceae (3 genera). The identification of zooplankton samples results, obtained the composition of zooplankton species in research location are 41 types consists of 6 phylum, which was the Arthropod, Chaetognatha, Cnidarians, Echinoderms, Molluscs and Annelids. There were 43 acoustics echogram data has been processed 7038 polygons to get 7 variable descriptors in 3 categories, namely morfometrik (high), bathymetric (depth and relative height) and energetic (Sv, skewness and kurtosis, Sa). K-means Cluster analysis results showed that the variables of Scattering volume and skewness were very influential in form a cluster while another variables. Discriminant analysis has shown that the contribution of 7 descriptors are used to form the descriptors are Sv (> 20%), Sa, depth and kurtosis contributed to 15-20%, and skewness contributed under 10- 14.99%. The discriminant function model is obtained from the results of this research provide the precision for 9 sampling time groups is 26.3% for classification.
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Judul: Nilai Hambur Balik Plankton di Perairan Teluk Palabuhanratu Menggunakan SIMRAD EK-15
Abstrak: Plankton adalah salah satu organisme mikroskopis yang berada di perairan dan membutuhkan sinar matahari untuk melakukan fotosintesis. Kelimpahan plankton dapat dideteksi dengan SIMRAD EK-15 yang merupakan alat akustik echosounder single beam. Penelitian ini bertujuan untuk menganalisis pola sebaran nilai Volume Backscattering strength ( ̅̅̅̅ ), menganalisis kondisi lingkungan dan mengamati spesies plankton yang berada di perairan Teluk Palabuhanratu. Metode yang digunakan untuk mengetahui kelimpahan plankton di Teluk Palabuhanratu adalah metode hidroakustik. Metode hidroakustik adalah metode yang menggunakan gelombang suara untuk mengamati dan menjelajahi sumber daya di perairan. Hasil dari kondisi lingkungan perairan di Teluk Palabuhanratu menghasilkan lima parameter yaitu suhu (28,45°C - 29,24°C), Kecerahan (1,5 m - 6,5 m), salinitas (26,63 psu – 33,18 psu), DO (5,95 mg/L - 6,66 mg/L), dan pH (8 - 8,9). Hasil pengamatan spesies plankton yang ditemukan terdiri dari zooplankton (8 genus) dan fitoplankton (109 genus). Kelas Globothalamea adalah kelas terbanyak yang ditemukan pada zooplankton dan kelas Bacillariophyceae adalah kelas terbanyak yang ditemukan pada fitoplankton. Hasil kelimpahan plankton yang direkam menggunakan alat akustik SIMRAD EK-15 menghasilkan tiga data persebaran kelimpahan plankton. Kelimpahan plankton pada persebaran horizontal dan vertikal memiliki nilai ( ̅̅̅̅) tertinggi banyak ditemukan di tengah lokasi penelitian. Hasil kelimpahan plankton secara temporal tidak terdapat perbedaan signifikan antara pagi dan siang karena dipengaruhi oleh musim peralihan II (Oktober). Hasil penelitian di Teluk Palabuhanratu memberikan informasi tentang distribusi kelimpahan plankton yang dapat digunakan untuk memahami kondisi perairan dan potensi kesuburan perairan di Teluk Palabuhanratu., Plankton is one of the microscopic organisms found in aquatic environments, relying on sunlight for photosynthesis. The abundance of plankton can be detected using the SIMRAD EK-15, which is a single-beam acoustic echosounder device. This research aims to analyze the distribution patterns of Volume Backscattering Strength ( ̅̅̅̅ ), assess environmental conditions, and observe plankton species in the waters of Palabuhanratu Bay. The method used to determine the abundance of plankton in Palabuhanratu Bay is hydroacoustic method. Hydroacoustic method employs sound waves to observe and explore aquatic resources. The results of the environmental conditions in Palabuhanratu Bay produced five parameters: temperature (23°C - 30.3°C), brightness (1.5 m - 6.5 m), salinity (37ppt - 28.5ppt), dissolved oxygen (5.95 mg/L - 6.66 mg/L), and pH (8 - 8.9). The observed plankton species consisted of zooplankton (8 genera) and phytoplankton (109 genera). The class Globothalamea was the most common among zooplankton, while the class Bacillariophyceae was the most common among phytoplankton. The recorded abundance of plankton using the SIMRAD EK-15 acoustic device resulted in three data sets of plankton abundance distribution. Plankton abundance in horizontal and vertical distribution had the highest ( ̅̅̅̅) values commonly found in the central part of the research location. Temporally, there was no significant difference in plankton abundance between morning and afternoon due to the influence of the transitional season II (October). The research in Palabuhanratu Bay provides information about the distribution of plankton abundance that can be used to understand the condition of the water and the potential fertility of the waters in Palabuhanratu Bay.
Keyword: Fitoplankton. Hidroakustik, Plankton, SIMRAD EK-15, Teluk Palabuhanratu, Volume Backscattering strength, Zooplankton

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf