1,720,995 research outputs found
Broad-band continuously tunable all-fibre DFB lasers
No full textUp to 27-nm continuous tuning is demonstrated from Er/Yb all-fiber distributed-feedback (DFB) lasers using a simple tuning technique for axial extension and compression. The demonstrated devices operate with powers up to 10 dBm and remain operating in single mode over the full tuning range. Our results represents the broadest tuning-range previously reported in any DFB laser configuration and demonstrate that uniform compression tuning of long Bragg gratings is possible with high reliability
Simple broadrange tuning of fibre-DFB lasers
No full textAll-fibre distributed feedback (DFB) lasers providing continuous tuning over 27nm are demonstrated for the first time. Extended wavelength coverage of the lasers is obtained using a simple bend-tuning technique which delivers undistorted outputs over the full tuning-range
A General Introduction to International Bioenergy Trade
No full textThe development of functional international markets for bioenergy has become an essential driver to develop bioenergy potentials, which are currently under-utilised in many regions of the world. Technical potential of bioenergy may be as large as 500 EJ/yr by 2050. However, large uncertainty exists about important factors such as market and policy conditions that affect this potential. Potential deployment levels by 2050 could lay in the range of 100–300 EJ/yr. Realizing this potential represents a major challenge but would substantially contribute to the world’s primary energy demand in 2050. The possibilities to export biomassderived commodities for the world’s energy market can create important socioeconomic development incentives for rural communities. But bioenergy markets are still immature, relying on policy objectives and incentives, that prove to be erratic in many cases. Further improvement is needed to develop both supply and demand in a balanced way and avoid distortions and instability that can threaten investments. Furthermore, it is necessary to develop and exploit biomass resources in a sustainable way and to understand what this means in different settings. In some markets, prices of biomass resources are volatile, including indirect effects on price of raw material prices for e.g. the forest industry as well as on food. Sustainability demands serve as a starting point for policies supporting bioenergy in many countries. The proliferation of initiatives registered worldwide to develop and implement sustainability frameworks and certifi cation systems for bioenergy, can lead to a fragmentation of efforts. This asks for harmonization and for international collaboration
Fibre Bragg grating compression-tuned over 110nm
No full textA fibre Bragg grating with a tuning range covering beyond the C- and L-bands has been realised, which represents the broadest tuning range reported of any Bragg grating. The device exhibits constant spectral response and polarisation mode dispersion within these bands
Over 70nm wideband tuning of fiber Bragg gratings using a compressive bending technique
No full textWe demonstrate, for the first time, a silica-based fiber Bragg grating (FBG) with a wavelength tuning range over 70 nm, using compressive bending given by a simple tuning package. The wide tuning range of the device (from 1614 nm to 1544 nm), covers the entire L-band and a half of the C-band. Its polarization-mode dispersion (PMD) and polarization-dependent loss (PDL) remain low over the full operating regime
Widely tunable fibre Bragg grating filters
No full textTo enhance the flexibility of deployed metro-networks, dynamically re-configurable systems might become necessary. A device that can meet the tough demands to one aspect in these, that is dynamic optical add-drop filtering, is the fibre Bragg grating (FBG). This is because it can be designed to provide sharp spectral band-edge roll-off and controlled phase performance, such that channels can be filtered with far better cross-talk suppression compared to any other current competing technology
Wavelength tuning of fiber Bragg gratings over 90nm using a simple tuning package
No full textWe demonstrate a silica-based tunable fiber Bragg grating filter with a wavelength tuning range over 90 nm. A bend-tuning technique in a simple tuning package is employed to obtain a wide wavelength tuning range from 1634 to 1544 nm, covering the entire L-band and a half of the C-band. The polarization-mode dispersion and polarization-dependent loss of the device show little variations over the whole operating region
Wideband compression-tuned all-fibre DFB laser: analysis and characterisation
No full textThe optical output from an all-fibre DFB-laser compression tuned over most of the C-band is analysed and characterised. The single-polarisation and line-width performance of the device is maintained across the full tuning range
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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