Analisis Kinerja Sistem Doppler VHF Omnidirectional Range dan Distance Measuring Equipment pada Navigasi Penerbangan

Navigasi udara merupakan kegiatan untuk mengarahkan transportasi udara dari satu tempat ke tempat yang lain agar tidak keluar dari jalurnya. Sistem transmisi sinyal pada Doppler VHF Omnidirectional Range (DVOR) belum sepenuhnya optimal karena persentase sinyal modulasinya sering mengalami peningkatan yang berakibat pada munculnya kondisi sinyal over-modulated. Deteksi sinyal interogasi maupun sinyal balasan pada Distance Measuring Equipment (DME) mengalami hambatan disebabkan oleh waktu tunda dan jarak pulsa yang tidak sesuai. Pada penelitian ini, akan dilakukan analisis kinerja sistem DVOR-DME dengan membandingkan nilai parameter dan nilai kondisi normal. Berdasarkan analisis kinerja sistem, didapatkan bahwa sistem DVOR-DME AirNav Indonesia Distrik Tanjungpinang beroperasi dengan normal. Nilai optimal 30Hz MOD dan 9960Hz MOD pada DVOR berada pada rentang nilai normal yaitu sebesar 30%. Nilai optimal delay dan spacing pada DME berada pada rentang nilai delay normal dan nilai spacing normal yaitu sebesar 50,01 μs dan 12,02 μs

Uji Efikasi Herbisida Glifosat Terhadap Pertumbuhan Dan Produksi Beberapa Varietas Jagung Produk Rekayasa Genetika

The study on the efficacy of glyphosate on the growth and yield of genetically modified corn varieties. The study aims to determine the efficacy of glyphosate on the growth and yield two varieties of genetically modified corn. The study was carried out at “Balai Benih Induk”, Tanjung Selamat, Medan from March to June 2012. Four treatments namely stacked genetically modified corn “X” x genetically modified corn “Y” (sprayed with glyphosate), genetically modified corn “X” (no glyphosate application, manual weeding), genetically modified corn “Y” (sprayed with glyphosate), hybrid DK979 (no glyphosate application, manual weeding). The result showed that glyphosate did not affect genetically modified corn

The cholesterol-raising diterpenes from coffee beans increase serum lipid transfer protein activity levels in humans

Cafestol and kahweol–diterpenes present in unfiltered coffee— strongly raise serum VLDL and LDL cholesterol and slightly reduce HDL cholesterol in humans. The mechanism of action is unknown. We determined whether the coffee diterpenes may affect lipoprotein metabolism via effects on lipid transfer proteins and lecithin:cholesterol acyltransferase in a randomized, double-blind cross-over study with 10 healthy male volunteers. Either cafestol (61–64 mg/day) or a mixture of cafestol (60 mg/day) and kahweol (48–54 mg/day) was given for 28 days. Serum activity levels of cholesterylester transfer protein, phospholipid transfer protein and lecithin:cholesterol acyltransferase were measured using exogenous substrate assays. Relative to baseline values, cafestol raised the mean (±S.D.) activity of cholesterylester transfer protein by 18±12% and of phospholipid transfer protein by 21±14% (both P<0.001). Relative to cafestol alone, kahweol had no significant additional effects. Lecithin:cholesterol acyltransferase activity was reduced by 11±12% by cafestol plus kahweol (P=0.02). It is concluded that the effects of coffee diterpenes on plasma lipoproteins may be connected with changes in serum activity levels of lipid transfer proteins

“When Out Is In”: Community Mobilization through Social Marketing in Nearshore Fisheries in Panabo City, Mindanao Island, Philippines

A pride campaign in Panabo City was implemented from 2012 to 2014 to inspire local fishers to change their behavior so that they will use only the allowed fishing gear, hook and line in buffer zone and fish only outside the no-take zone to reduce the threats and preserve coral cover and fish population in Cagangohan Fish Sanctuary. The Rare’s Theory of Change (TOC), hypothesis and impact assessment framework were used in the study. The analysis involved evaluation of social marketing and barrier removal strategies using quantitative (KAP) and qualitative (Non-KAP) data during pre and post campaign. Thirty five social marketing and 30 barrier removal activities were conducted that were complemented with 30 social marketing materials. The results of the campaign are as follows: increased level of fishers’ knowledge on fish sanctuary location, rules and regulations, and MPA benefits; increased level of fishers’ belief that non-compliance of rules and regulations results in the decline of fish populations and on MPA benefits; increased level of fishers’ interpersonal communication on fish sanctuary location, rules and regulations and MPA benefits; increased MPA management effectiveness from level 0 to level 2; behavior change and decreased intrusion into the no-take-zone, and use of non-allowed fishing gear in buffer zone; and the preservation of coral cover and fish biomass. The increase in desired behavior has reduced the threats to fish sanctuary but did not increase coral cover and fish population as the expected conservation result. However, a strong capacity and constituency was established during the campaign implementation that needs to be sustained in year 3 and beyond

Neutron radioactivity—Lifetime measurements of neutron-unbound states

A new technique to measure the lifetime τ of a neutron-radioactive nucleus that decays in-flight via neutron emission is presented and demonstrated utilizing MonteCarlo simulations. The method is based on the production of the neutron-unbound nucleus in a target, which at the same time slows down the produced nucleus and the residual nucleus after (multi-) neutron emission. The spectrum of the velocity difference of neutron(s) and the residual nucleus has a characteristic shape, that allows to extract the lifetime. If the decay happens outside the target there will be a peak in the spectrum, while events where the decay is in the target show a broad flat distribution due to the continuous slowing down of the residual nucleus. The method itself and the analysis procedure are discussed in detail for the specific candidate 26O. A stack of targets with decreasing target thicknesses can expand the measurable lifetime range and improve the sensitivity by increasing the ratio between decays outside and inside the target. The simulations indicate a lower limit of measurable lifetime τ∼0.2 ps for the given conditions

Development of a Hydrous Ethanol Fuel Feeding Device for Spark-Ignition Engine

While the Philippine Biofuels Act of 2006 mandates the use of anhydrous bioethanol as blend for gasoline, the potential of hydrous ethanol as an alternative fuel for spark-ignition engines has not been fully realized. This study explored the possibility of using hydrous ethanol as fuel for spark-ignition engines with minimal modifications and without the need for gasoline blend. A fuel feeding device was developed to feed hydrous ethanol fuel into the intake manifold of the engine, bypassing the carburetor. By replacing the components that are not compatible with hydrous ethanol and installing a fuel feeding device developed at PhilRice, two spark-ignition engines were able to run solely on 80-95% hydrous ethanol fuel. The fuel economy was found to be a significant issue in the utilization of hydrous ethanol fuel as there is a 75% increase in fuel consumption when using hydrous ethanol. There is potential for hydrous ethanol to be used as fuel if it can be produced locally and sold at half the pump price of gasoline

Efficiency determination of resistive plate chambers for fast quasi-monoenergetic neutrons

Composite detectors made of stainless steel converters and multigap resistive plate chambers have been irradiated with quasi-monoenergetic neutrons with a peak energy of 175MeV. The neutron detection efficiency has been determined using two different methods. The data are in agreement with the output of Monte Carlo simulations. The simulations are then extended to study the response of a hypothetical array made of these detectors to energetic neutrons from a radioactive ion beam experiment.Comment: Submitted to Eur.Phys.J. A; upgraded version correcting some typos and updating ref.