4,765 research outputs found
Electronic transport in a Cantor stub waveguide network
We investigate theoretically, the character of electronic eigenstates and
transmission properties of a one dimensional array of stubs with Cantor
geometry. Within the framework of real space re-normalization group (RSRG) and
transfer matrix methods we analyze the resonant transmission and extended
wave-functions in a Cantor array of stubs, which lack translational order.
Apart from resonant states with high transmittance we unravel a whole family of
wave-functions supported by such an array clamped between two-infinite ordered
leads, which have an extended character in the RSRG scheme, but, for such
states the transmission coefficient across the lead-sample-lead structure
decays following a power-law as the system grows in size. This feature is
explained from renormalization group ideas and may lead to the possibility of
trapping of electronic, optical or acoustic waves in such hierarchical
geometries
Factors Affecting Farmer Motivation in Requesting Duck Farm Credit: a Case Study in Cirebon, West Java, Indonesia
Objectives of study was to observe and to analyze the farmer motivation in requesting farmer credit(bank loan) for duck, based on farmer characteristics and communication behavior. Sample was chosenamong duck farmers in Kroya village, Cirebon. Characteristic factors were: age, part-timer farmer, farmsize, experience, education, and income. While the communication behavior factors werecommunicating with extension worker or credit officer, and participating in social problems. Farmermotivation to apply credit impacted by their characteristics, such as educational level, income and age.Communication behavior, such as participating in extension activities and social organization,were moreimpacted to apply credit, than farmer characteristics. Communication activities can be used to persuadefarmer to apply credit
The performance of modified jatropha-based nanofluid during turning process
The industry's extensive use of petroleum-based metalworking fluid (MWF) harms the environment
and humans. The production of bio-based MWF, especially from crude jatropha oil (CJO), has therefore taken
numerous initiatives. This aimed to formulate newly modified jatropha oil (MJO) with the addition of 0.05wt.%
hBN and 0.05wt.% MoS2 as the nanofluid for MWF. The performance of the nanofluids was determined
through the turning process in terms of cutting temperature, workpiece surface roughness, tool life and tool
wear of the tool lubricated by the nanofluids. The performance of the nanofluid samples was compared with
the synthetic ester (SE). From the results, after conducted 100mm axial cutting length MJO+hBN+MoS2
recorded the lowest in cutting temperature and surface roughness compared to all samples. The result shows
that MJO+hBN+MoS2 has longer tool life (6500mm) compared to SE (6000mm). Abrasion and adhesion were
observed as the dominant tool wear mechanism. In conclusion, MJO+hBN+MoS2 shows better machining
performance and has the potential to be an environmentally friendly metalworking fluid
Detection of quantum light in the presence of noise
Detection of quantum light in the presence of dark counts and background
radiation noise is considered. The corresponding positive operator-valued
measure is obtained and photocounts statistics of quantum light in the presence
of noise is studied.Comment: 4 pages, 1 figure; misprints correcte
Efficient graphene-based photodetector with two cavities
We present an efficient graphene-based photodetector with two Fabri-P\'erot
cavities. It is shown that the absorption can reach almost 100% around a given
frequency, which is determined by the two-cavity lengths. It is also shown that
hysteresis in the absorbance is possible, with the transmittance amplitude of
the mirrors working as an external driving field. The role of non-linear
contributions to the optical susceptibility of graphene is discussed.Comment: 10 pages, 8 figures. published version: minor revisio
IR optical fiber-based noncontact pyrometer for drop tube instrumentation
The design of a two color pyrometer with infrared optical fiber bundles for collection of the infrared radiation is described. The pyrometer design is engineered to facilitate its use for measurement of the temperature of small, falling samples in a microgravity materials processing experiment using a 100 meter long drop tube. Because the samples are small and move rapidly through the field of view of the pyrometer, the optical power budget of the detection system is severly limited. Strategies for overcoming this limitation are discussed
Entangled-Photon Imaging of a Pure Phase Object
We demonstrate experimentally and theoretically that a coherent image of a
pure phase object may be obtained by use of a spatially incoherent illumination
beam. This is accomplished by employing a two-beam source of entangled photons
generated by spontaneous parametric down-conversion. Though each of the beams
is, in and of itself, spatially incoherent, the pair of beams exhibits
higher-order inter-beam coherence. One of the beams probes the phase object
while the other is scanned. The image is recorded by measuring the photon
coincidence rate using a photon-counting detector in each beam. Using a
reflection configuration, we successfully imaged a phase object implemented by
a MEMS micro-mirror array. The experimental results are in accord with
theoretical predictions.Comment: 11 pages, 3 figures, submittedto Phys. Rev. Let
Perbandingan Efektivitas Media Cetak (Folder dan Poster-Kalender) dan Penyajian Tanaman Zodia terhadap Peningkatan Pengetahuan Masyarakat
Objectives of research were to determine the combination treatment of printed material (folder media and calendarposter)combined with Zodia plant toward increasing community knowledge in North Bogor sub-district. Design ofresearch was a quasi-experimental design. Sample was chosen in the endemic area of dengue disease (DBD).Sampling design was a separate sample pretest-posttest control group design. Experimental design was a 2x3factorial design. Respondents were totally 90 housewives, divided into six groups. Research result was: (1)effectiveness of printed media can be increased toward phisical media USAge; (2) increasing knowledge was veryeffective toward media combination; (3) folder combined with Zodia plant was more effective to increase communityknowledge; Community knowledge was emphasis on utilizing Zodia plant to prevent mosquito as an agent of denguedisease; (4) several characteristic factors were increase community knowledge effectively, (5) innovation factorswere also effectively increase community knowledge. It was concluded that folder media combined with Zodia wasthe most effective media to deliver a message of Zodia plant to increase community knowledge
Food composition and feeding ecology of the Red Fox Vulpes vulpes (Linnaeus, 1758) in Egypt
Food composition of the Red Fox Vulpes vulpes populations in different habitats in Egypt is investigated based on the analysis of stomach contents. The analysis of 70 stomach contents demonstrates that the food of Red Fox is highly diverse and includes rodents, birds, reptiles,fishes, insects and other arthropods, fruits and other vegetable material. Certain individuals seem to also feed on carrion. Diet composition shows seasonal and geographical variations that are apparently associated with changes in the availability of different food items. The results clearlyshow that the Red Fox is an opportunistic omnivore, capable of adapting to a great variety of dietary compositions
Two-dimensional Nanolithography Using Atom Interferometry
We propose a novel scheme for the lithography of arbitrary, two-dimensional
nanostructures via matter-wave interference. The required quantum control is
provided by a pi/2-pi-pi/2 atom interferometer with an integrated atom lens
system. The lens system is developed such that it allows simultaneous control
over atomic wave-packet spatial extent, trajectory, and phase signature. We
demonstrate arbitrary pattern formations with two-dimensional 87Rb wavepackets
through numerical simulations of the scheme in a practical parameter space.
Prospects for experimental realizations of the lithography scheme are also
discussed.Comment: 36 pages, 4 figure
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