526 research outputs found
Penggunaan Limbah Ikan Leubiem (Chanthidermis maculatus) dalam Ransum terhadap Kelayakan Usaha Itik Petelur Fase Starter
Pakan merupakan faktor yang memengaruhi biaya produksi itik petelur, biaya pakan mencapai 70% dari total biaya produksi, untuk itu diperlukan pakan alternatif yang dapat mengurangi biaya produksi, salah satunya adalah limbah ikan leubiem (Chanthidermis maculatus). Penelitian bertujuan untuk mengevaluasi penggunaan limbah ikan leubiem dalam ransum terhadap kelayakan usaha itik petelur fase starter. Materi penelitian yang digunakan 500 ekor itik petelur umur 1 hari (DOD). Perlakuan ransum yang digunakan: P1 (ransum kontrol/tanpa limbah ikan leubiem), P2 (ransum mengandung 10% kulit ikan leubiem), P3 (ransum mengandung 10% kepala ikan leubiem), P4 (ransum mengandung 10% tulang ikan leubiem) dan P5 (ransum mengandung 10% kombinasi limbah ikan leubiem). Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) yang terdiri 5 perlakuan dan 4 ulangan. Variabel yang diamati adalah: harga ransum, biaya produksi, IOFC, penerimaan (hasil penjualan), keuntungan dan kelayakan usaha. Data yang diperoleh ditabulasi dan dikalkulasi sesuai dengan variabel penelitian. Hasil penelitian menunjukkan bahwa harga ransum itik petelur fase starter berkisar antara Rp. 4.081,- 5.205,-/kg. Total biaya produksi terendah terdapat pada perlakuan ransum P5 yaitu Rp. 26.270,-/ekor. Penerimaan diperoleh dari hasil penjualan itik petelur fase starter berdasarkan bobot hidup Rp. 40.000/kg. IOFC dan keuntungan tertinggi diperoleh pada perlakuan ransum P5 yaitu Rp. 17.318,-/ekor. Kelayakan usaha berdasarkan nilai BC dan RC ratio dari semua perlakuan ransum menunjukkan nilai yang diperoleh lebih besar dari 0 dan 1. Hal ini menunjukkan bahwa usaha itik petelur menguntungkan dan layak diusahakan. Disimpulkan bahwa usaha peternakan itik petelur fase starter dengan penggunaan limbah ikan leubiem dalam ransum layak untuk diteruskan dan menguntungkan
Estimation of temperature and electron density in stainless steel plasma using laser induced breakdown spectroscopy
LIBS plasma produced by a 1064 nm Q-switched Nd:YAG laser in an atmospheric pressure was studied for the stainless steel sample. The laser output energy 150 mJ with pulse duration of 6 ns. The plasma emission spectrum was recorded by the LR1 Spectrometer connected to the fibre optic. The plasma temperature and electron density of each element were estimated by time-resolved spectroscopy of neutral atom and ion line emission. The plasma temperature was obtained from the Boltzmann plot method and their electron density was determined by using Saha-Boltzmann equation method. The preliminary qualitative LIBS analysis shows that several elements contained in the stainless steel. The element detected was Cu, Fe, Mn, Ni, and Cr. The results shows that Mn and Fe has the highest plasma temperature of 1.2 eV, but the electron density of Mn was the highest with value 4.6x1020 cm-3, while the Cu has the lowest temperature that is 0.73 eV with the electron density 2.8x1017 cm-3. The results are discussed
Plasma splashing from Al and Cu materials induced by and Nd : YAG pulsed laser
Plasma splashing from Al and Cu target materials and the growth of thin films on Cu and Al, respectively, has been studied using a Q-switched Nd:YAG laser with a 1064-nm, 80-mJ, 8-ns pulse width as the source of ablation. The target kept rotating and the substrate, Cu for Al and vice versa, was placed at an angle of 15° with respect to the beam axis. During the laser-matter interaction, the targets absorbed thermal energy within the thermal region depth of 4.7 (1.1) nm, yielding an ablated skin depth of 6.7 (4.2) nm. The surface morphology of the exposed targets was studied by analyzing SEM micrographs obtained using a ZEISS SUPRA 35 VP. The obtained results are explained on the basis of different sputtering/ablation mechanisms. Comparatively severe damage forming a bigger crater is seen on the Al target surface in contrast to the crater on the Cu surface. This observation is correlated with the blustering effect and/or debris formation. Energy dispersive spectroscopy (EDX) of the substrates yielded the deposition of micrometric grain-size particle
Analisis Kelayakan USAha Agroindustri Tempe
Penelitian ini bertujuan untuk mengetahui: (1) besarnya biaya, penerimaan, dan pendapatan agroindustri tempe di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis; (2) kelayakan USAha agroindustri tempe di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis. Penelitian dilaksanakan di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis dengan menggunakan metode survai. Sampel lokasi ditentukan secara sengaja (purposive) dengan pertimbangan bahwa Desa Pawindan merupakan sentra agroindustri tempe di Kecamatan Ciamis. Teknik penarikan responden dilakukan secara sensus. Hasil penelitian menunjukkan bahwa: Rata-rata biaya total sebesar Rp 1.274.208,90, yang dihasilkan dari penjumlahan biaya tetap rata-rata sebesar Rp 17.427,24, dengan biaya variable rata-rata sebesar Rp 1.256.781,70. Pendapatan rata-rata yang diperoleh sebesar Rp 644.791,09, dari penerimaan rata-rata sebesar Rp 1.919.000,00,- dikurangi biaya total rata-rata sebesar Rp 1.274.208,90. Analisis Kelayakan yang digunakan yaitu analisis kelayakan USAha yang membandingkan antara penerimaan dan biaya total. Rata-rata penerimaan yang diperoleh sebesar Rp 1.919.000,00,- dan biaya total rata-rata yang dikeluarkan sebesar Rp 1.274.208,90. Dengan demikian diperoleh R/C sebesar 1,50 artinya berarti bahwa USAha agroindustri tempe layak untuk dijalankan
Competing risks for reliability analysis using Cox’s model
Purpose – Cox’s model with Weibull distribution and Cox’s with exponential distribution are the most important models in reliability analysis. This paper seeks to show that, with a large sample size based on expectation maximization (EM) algorithm, both models give similar results.
Design/methodology/approach – The parameters of the models have been estimated by method of maximum likelihood based on EM algorithm. The objective of this analysis is to fit the modification of Cox’s model with Weibull distribution and Cox’s with exponential distribution, examine its
performance and compare their results with Crowder et al.
Findings – A simulation study indicates that the parametric Cox’s model with Weibull distribution gives similar results to Cox’s with exponential distribution, especially for a large sample size. Also, the modification of the two models showed better results compared with Crowder et al., especially for the second causes of failure.
Originality/value – A modification of the two competing risk models has mostly been applied in failure time data and simulation data. The results of the simulation study indicate that the Weibull and exponential are suitable for Cox’s model as they are easy to use and it can achieve even higher accuracy compared with other distribution models
Caffeine as A Natural Corrosion Inhibitor for Mild Steel in Nacl Solution
Corrosion inhibitors are substances that added to the environment in small concentration and can effectively reduce the corrosion rate that of a metal surface. Natural inhibitors are one types of inhibitor being researched as it brings less environmental impact on the environment. This research was focused on the application of caffeine as inhibitor for corrosion of mild steel in seawater condition. The objective of this project was to develop the relationship between caffeine concentration on the corrosion of mild carbon steel in both static and moving solution contained 3.5-wt% NaCl. Three types of solution were prepared, which are NaCl without addition of caffeine, NaCl with 1-wt% of caffeine and NaCl with 2-wt% of caffeine. Corrosion testing was carried out by weight loss measurement. The microstructures of corroded mild steel specimens were observed under optical microscope. The experimental results indicated that by adding caffeine into the environment medium, weight loss of mild steel specimen was reduced. The corrosion rate of specimens was decreased when more caffeine was added to the environment. From optical microscopic observation, caffeine performed its inhibition effect likely by forming a protective layer which acts as barrier to prevent further corrosion of mild steel in NaCl solution
Arc discharge synthesis of CNTs in hydrogen environment in presence of magnetic field
In this study the effect of hydrogen ambient environment on the growth of carbon nanotubes by arc discharge plasma in presence of external magnetic field is investigated. The samples collected from cathode deposit are analyzed by field emission scanning electron microscopy and Raman spectroscopy. Results show an increase in carbon nanotube growth with increase in hydrogen ambient pressure. The magnetic field considerably enhances the growth of carbon nanotube as observed in FESEM micrographs. In Raman spectrum, high intensity of G peak as compared to D peak indicates the presence of high quality nanotubes. Magnetic effect remarkably decreases ID/IG ratio from 1.55 to 0.31 for ambient pressure 10 mbar
Impact damage resistance and post impact tolerance of optimum banana-pseudo stem fiber reinforced epoxy sandwich structures
Banana fiber has a high potential for use in fiber composite structures due to its promise as a polymer reinforcement. However, it has poor bonding characteristics with the matrixes due to hydrophobic-hydrophilic incompatibility, inconsistency in blending weight ratio, and fiber length instability. In this study, the optimal conditions for a banana/epoxy composite as determined previously were used to fabricate a sandwich structure where carbon/Kevlar twill plies acted as the skins. The structure was evaluated based on two experimental tests: low-velocity impact and compression after impact (CAI) tests. Here, the synthetic fiber including Kevlar, carbon, and glass sandwich structures were also tested for comparison purposes. In general, the results showed a low peak load and larger damage area in the optimal banana/epoxy structures. The impact damage area, as characterized by the dye penetration, increased with increasing impact energy. The optimal banana composite and synthetic fiber systems were proven to offer a similar residual strength and normalized strength when higher impact energies were applied. Delamination and fracture behavior were dominant in the optimal banana structures subjected to CAI testing. Finally, optimization of the compounding parameters of the optimal banana fibers improved the impact and CAI properties of the structure, making them comparable to those of synthetic sandwich composites
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