Judul: Optimasi penyemprotan cairan di bagian pengabut pada mesin pengabut gendong bermotor (Mist Blower)
Abstrak: Kinerja mist blower dinilai berdasarkan efektivitas dan efisiensi, yaitu ukuran diameter droplet, keseragaman, dan lebar penyemprotan efektif (LPE). Tujuan penelitian ini adalah untuk melakukan uji penyemprotan mist blower pada berbagai perlakuan di dalam ruangan dan di lahan agar diperoleh kombinasi perlakuan terbaik. Penelitian di laboratorium menggunakan perlakuan kecepatan angin lingkungan 0 m/s dan 2.13 m/s, sedangkan penelitian di lahan menggunakan perlakuan kecepatan angin lingkungan alami yang terukur sebesar 0.5 m/s. Tuas blower maksimum dan debit minimum (B4D2) adalah kombinasi perlakuan terbaik. Penyemprotan menggunakan kombinasi ini menunjukkan hasil paling efektif dan efisien, yaitu menghasilkan ukuran diameter droplet paling kecil sebesar 100 μm dan LPE paling tinggi sebesar 68 cm. Corong pengarah bersudut 46.42° (lebih besar dari sudut nosel) menghasilkan penyemprotan paling seragam.
Keyword: Corong, Nosel, Debit penyemprotan, Distribusi penyemprotan

Judul: Optimasi sistem penyemprotan cairan pada sistem bagian pengabut mesin sprayer gendong bermotor (knapsack power sprayer)
Abstrak: Kinerja sprayer ditentukan oleh efektivitas dan efisiensinya yaitu, ukuran diameter droplet, keseragaman, debit, dan lebar penyemprotan efektif. Tujuan penelitian ini adalah melakukan optimasi penyemprotan pada bagian pengabut sprayer gendong bermotor (knapsack power sprayer). Penelitian ini menggunakan fan dan corong pengarah pada batang nosel. Sistem optimasi ditempuh dengan empat perlakuan, yaitu bukaan gas (throttle), bukaan kran (katup buka/tutup), kecepatan udara dari fan penghembus dan dimensi corong pengarah dengan melibatkan dua kondisi kecepatan angin di dalam laboratorium yaitu 0 m/s dan 1.7 m/s. Hasil rancangan fan dan corong pengarah mampu meningkatkan lebar penyemprotan efektif dan memperkecil diameter droplet. Setting sprayer yang menghasilkan kinerja optimum terdapat pada perlakuan bukaan gas sedang dan bukaan kran sedang. Kinerja sprayer optimum tersebut menghasilkan tekanan 24 kgf/cm2, debit 0.724 liter/menit, lebar penyemprotan efektif 80 cm, dan diameter droplet 326.65 μm.
Keyword: droplet, spraying width, spayer

Judul: Studies on growth spurt and aging in higher primates
Abstrak: single measurement that best defines the health and nutritional status of children, just as it provides an indirect measurement of the quality of life of an entire population. The pattern of human growth reflects the biocultural evolution of our species. The human pattern of growth and development (ontogeny) appears to differ markedly from patterns of ontogeny in other primate species. Three studies are reported here which deal to the growth and development of human and chimpanzee (Pan troglodytes). These three studies allow us to contrast the phenomena of adolescence growth spurt and female elderly bone loss in chimpanzee and human as chimpanzee is the closest species to humans within extant nonhuman primates. In the first, a cross-sectional study of growth of the body size and somatotype of 363 Javanese girls and 299 Javanese boys aged 4 to 20 years from Magelang Regency, Indonesia was described. In the second, cross-sectional and longitudinal studies in the growth of chimpanzee second metacarpal bone linear dimensions from individuals aged 0 to 43.6 years were used for comparison. While in the third, cross-sectional and longitudinal studies in the growth of chimpanzee body size (body mass and anterior trunk length) and second metacarpal bone mineral content were derived. In measuring the second metacarpal dimensions and mineral content, a total of 568 radiographs of chimpanzee's proximodistal left hands were used. They were taken from 68 females and 49 males aged 0 to 43.62 years old. We applied an image analysis system, Scion Image Release Alpha 4.0.3.2 software for Windows to measure bone linear dimensions and bone mineral content. Humans present complex and sinuous growth curves for both body weight and height. A clear growth spurt could be demonstrated by cross-sectional analysis in our girl subjects at around aged 11.5 years and in our boy subjects at around aged 12.5 years. In longitudinal series, not in cross-sectional, several representative chimpanzees of both sexes showed a pre-adult growth spurt on the body sizes, bone dimensions and bone mineral content. They ranged at age 4.5 to 8.5 years. This underscore the fact that adolescent growth spurt in linear dimension was not a universal feature of anthropoid primate ontogeny. Bone loss is a well established characteristic of human female aging. Based on crosssectional analyses the sequential decline of bone mass in female chimpanzee may be said to be genuine. On the other hand, we found in adulthood through elderly, male chimpanzees show a longer plateau than female chimpanzee, that is, bone mineral content is maintained in male.
Keyword: Javanese children, growth spurt, chimpanzee, second metacarpal bone, bone loss, Higher Primates