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Kelimpahan Serangga Air di Sungai Toraut Sulawesi Utara Candra, Yudi; Langoy, Marnix; Koneri, Roni; Singkoh, Marina F. O.
JURNAL MIPA UNSRAT ONLINE Vol 3, No 2 (2014)
Publisher : Sam Ratulangi University

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Abstract

Serangga air merupakan kelompok Arthropoda yang dapat dijumpai hampir pada jenis perairan misalnya pada habitat lentik atau lotik. Seranggan air dalam suatu ekosistem berperan penting dalam rantai makanan selain itu juga serangga air dapat dijadikan sebagai bioindikator terhadap penentuan kualitas suatu perairan. Penelitian ini bertujuan untuk menganalisis kelimpahan serangga air yang terdapat di Sungai Toraut. Lokai penelitian terletak pada Sub DAS dari DAS Dumoga Kabupaten Bolaang Mongondow, Sulawesi Utara. Sungai ini memiliki luas sekitar 249 km2 dan hulunya terletak di Taman Nasional Bogani Nani Wartabone (TNBNW). Penelitian ini menggunakan metode Purposive Random Sampling dengan menggunakan alat surber sampler. Total individu yang didapatkan dari 3 stasiun sebanyak 1497 individu dengan jumlah famili sebanyak 24 yang terdiri dari 27 spesies. Spesies serangga air yang paling banyak ditemukan pada stasiun satu, sedangkan yang sedikit pada stasiun 3. Kelimpahan spesies yang paling banyak ditemukan adalah Hydropsyche sp.Arthropods is a group of aquatic insects that can be found in almost all types of aquatic habitats for example lentic or lotic habitat. In the field of ecology, aquatic insects plays a role in the food chain, moreover the aquatic insects can be used as bioindicator to determine the quality of water. This study aims to analyze the abundance of aquatic insects found in the Toraut River. This study lies in the sub-watershed from the watershed of Dumoga Bolaang Mongondow, North Sulawesi. This river has an area of ​​approximately 249 km2 and its located in the headwaters of Bogani Nani Wartabone  National Park. The method used in this study is purposive random sampling method by using a sampler surber. Total individuals were obtained from 3 stations are 1497 individuals with total 24 families consisting of 27 species. The most commonly species of aquatic insects found at station 1, whereas slightly at station 3. The most commonly species of aquatic insects found is Hydropsyche sp.
ANALISIS KUAT TEKAN BETON TANPA TULANGAN DENGAN MENGGUNAKAN METODE UJI TAK RUSAK BERDASARKAN KECEPATAN GELOMBANG SONIK Candra, Yudi; Syech, Riad; ', Sugianto
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

A research on the testing of concrete elasticity has been done in order to measure concrete compressive strength  using a non destructive test based on sonic wave velocity. An equipment that was used for this research was a Sonic Wave Analyzer (SOWAN). In this research, concrete samples were formed in cylindrical shape with 15 cm diameter and 30 cm length. The compressive strengths of this concrete were 19  , 23    , and 25      ( ⁄ ). After that the time delay of sonic wave was measured. The research results showed that primary and secondary sonic wave velocity, elasticity, and compressive strenght were    = 3525 m/s,    = 1950 m/s,  23240  x N/ , and  24 x    ( ⁄ )  respectively. Based on the data, it was concluded that this non destructive test based on sonic wave velocity can be used to measure the concrete compressive strength, because the values obtained were comparable to the values obtained using the Universal Testing Machine (UTM) which is a destructive test.