Judul: Disain Model Alat pasteurisasi susu Otomatis
Abstrak: Pada umumnya, bahan pangan mempunyai sifat mudah rusak. Kerusakan ini tergantung dari jenis bahan pangannya, dapat berlangsung secara lambat misalnya pada biji-bijian, atau dapat berlangsung secara sangat cepat misalnya pada susu. Salah satu cara pengawetan bahan pangan adalah dengan menggunakan energi panas, misalnya cara pasteurisasi. Pasteurisasi merupakan suatu cara atau langkah dalam pengawetan yang biasa dilakukan pada susu. Pengaruh pasteurisasi susu antara sebagai berikut; air susu lebih lama dapat disimpan, раda suhu rendah malahan dapat disimpan beberapa hari; air su- su tidak lagi mengandung kuman-kuman patogen. Penelitian ini bertujuan untuk merancang suatu model alat pasteurisasi susu dengan memanfaatkan teknologi elektronik pada alat kontrol suhunya. Model alat pasteurisasi susu otomatis yang didisain terdiri dari dua bagian, yaitu alat pasteurisasi susu dan alat pengatur suhu. Bagian alat pasteurisasi terdiri dari tanki pasteurisasi, tanki medium pemanas, pompa dan unit pencatu daya. Sedangkan bagian alat pengatur suhu terdiri dari unit pengindera, unit penguat tegangan, unit penanding (comparator), unit penguat arus, unit kontrol (relai) dan unit pencatu daya. Dari hasil pengujian yang dilakukan terhadap keseragaman suhu, model alat pasteurisasi yang dibuat masih menghasilkan perbedaan suhu selama proses pasteurisasi. Waktu yang dibutuhkan untuk mencapai suhu pasteurisasi (63°C) dengan suhu awal 27, 29 dan 31.10 °C adalah berturut-turut 14.833, 14.733 dan 11.833 menit. Alat pengatur suhu yang dibuat dapat mencakup kisaran pengaturan suhu dari 40 sampai 75 °C, dengan selang kepekaan sebesar 0.003 volt. Penelitian lebih lanjut terhadap konstruksi tanki pasteurisasi dan sistim pengadukkannya perlu dilakukan untuk memperoleh tingkat keseragaman suhu yang lebih baik, begitu juga terhadap bahan pembalut sensor, kestabilan alat pengatur suhu, pengembangan rangkaian unit penanding (comparator) dan unit penguat serta kestabilan tegangan pada setiap unit fungsional alat pengatur suhu diperlukan untuk mempertinggi kualitas dan kemampuannya.
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Judul: Rancang Bangun Alat Pemerah Susu Sapi Otomatis dengan Pulsator Tipe Pegas
Abstrak: Milk is an important commodity for improving people nutrition. The main source of milk production is dairy cow. In Indonesia, milk production is dominated by local dairy herdsmen who are still applying milking manually by hand. Actually local dairy herdsmen can use milking machine which is built simple and appropriate with common components. This study aims at design and build automatic milking machine with spring type pulsator. This milking machine can be used by smallscale dairy herdsmen because it is easy to use and maintaince. By using this milking machine, milk is also expexted to be more hygienic. The main components to make up this milking machine are teat cups, spring type pulsator, DC Motor, AC-DC regulator, vacuum pump, milkcan, and frame. The specific distinction of this milking machine with the modern milking machine is no need a claw to connect 4 milk tubes on teat cups with 4 pulse tubes on pulsator. Claw’s function is not replaced by any component, but the milkcan itself is made as direct vacuum reservoir. Power source to run this milking machine is entirely using electricity. Vacuum pump requires 250 watt power to produce vacuum pressure up to 50 kPa at milkcan as vacuum reservoir. And DC motor requires DC voltage at 3-12 V with current 5A to drive the pulsator. Spring type pulsator can produce pulsation rate 60 cycle per minute with pulse ratio 2.5:1, which means the resting phase on teat cups is 2.5 times longer than massage phase. Testing result revealed that the performance of the machine has not produced milk as expexted. Vacuum flow rate which is produced by pump is less efficient if it works at very short time interval. While the resting phase, the pulsation chamber has just begun to connect with vacuum and the interval 5/7 second is too short to produce enough vacuum in order to open the teat cup liners. It is because the vacuum flow rate is nullified at a moment before, while the massage phase running.
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Judul: Lejeuneaceae Subfamily Ptychanthoideae (Hepaticae) in  West Java
Abstrak: Subfamily Ptychanthoideae of the family Lejeuneaceae (Hepaticae) in West Java is still poorly known. Publications on this subfamily are out of dated and written in the 19th or early of 20th century. The last taxonomic treatment of Ptychanthoideae of West Java was in 1933, many species names have changed since then. Studies on Ptychanthoideae of West Java are urgently needed. Studies on the Ptychanthoideae were based on the specimens collected from West Java. A total number of 361 of specimens deposited in the Herbarium Bogoriense (BO), Herbarium Biotrop (BIOT), Gottingen Herbarium (GOET) and Bangi Herbarium (UKMB) were examined, those are old and several recent specimens collected in West Java. Recent collections were made from Telaga Warna, Ciater, Gunung Halimun Salak National Park, Cibodas Botanical Garden, Bodogol Education Center and Conservation (Gunung Gede Pangrango National Park), University of Indonesia Campus Depok, including several collections from Banten Province. Twenty four species of Lejeuneaceae subfamily Ptychanthoideae are known from West Java, belonging to 8 genera namely Acrolejeunea (Spruce) Schiffn. (2 species), Archilejeunea (Spruce) Schiffn. (1 species), Lopholejeunea (Spruce) Schiffn. (10 species), Mastigolejeunea (Spruce) Schiffn. (3 species), Ptychanthus Nees (1 species), Schiffneriolejeunea Verd. (1 species), Spruceanthus Verd. (2 species) and Thysananthus Lindenb. (4 species). Two new records of Ptychanthoideae: Mastigolejeunea indica Steph. and Thysananthus minor Verdoorn are reported for Java. A determination key to the species is presented including their descriptions and illustrations.
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