We propose a simple kinetic model that can be used to improve the coupling coefficient value of a... more We propose a simple kinetic model that can be used to improve the coupling coefficient value of a single mode fiber coupler in the fabrication process. The proposed model is time independent, where the internal and external parametric functions are included. The simulation is integrated over the coupling ratio range for the various fiber separations. The coupling coefficient value of the device is examined by using the coupling ratio range from 1% to 75%. The result obtained is compared with the experimental results, where it is ...
Journal of Engineering, Design and Technology, 2009
Purpose A literature review is presented in the subject of construction plant and equipment man... more Purpose A literature review is presented in the subject of construction plant and equipment management (CPeM) to: delineate the subject; consider its development over recent years; and identify principal themes within it. The paper aims to close the gap in knowledge, by using ...
Incoherent broad-band cavity-enhanced absorption spectroscopy (IBB-CEAS) based on arc lamps has b... more Incoherent broad-band cavity-enhanced absorption spectroscopy (IBB-CEAS) based on arc lamps has been around for a few years, but only two reports exist using light-emitting diodes (LEDs). We present a setup based on a 643-nm LED which is of interest for the simultaneous detection of NO3 and NO2. The latter is chosen for testing as it is stable and available in calibrated diluted samples. A detection limit in the ppbv range is obtained with 2-min averaging (5×10-9 /cm rms baseline noise level), comparable to the best performance of chemiluminescence devices used for pollution monitoring. At 1-s acquisition time, the detection limit is below 10 ppbv. Extrapolation to NO3 yields a detection limit of a few pptv for a few minutes averaging. We also test the retrieval of absolute sample absorption (and concentration) using the cavity mirror reflectivity obtained with a commercial spectrophotometer, and we conclude that a calibration based on a reference sample of known concentration is preferable for accurate concentration measurements with IBB-CEAS. Finally, we present a rigorous frequency-domain derivation of cavity transmission as a function of wavelength for a broad-band spectrally smooth source, which complements the time-domain derivation by Fiedler et al. This derivation exposes an issue with multiple transverse mode excitation inherent to this technique, which may result in slightly distorted spectral profiles.
The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of ele... more The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, that is, by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy-momentum-mass relation, assuming a local energy density. This yields a theory of photon wave mechanics (PWM). The proper Lorentz-invariant single-photon scalar product is found to be non-local in coordinate space, and is shown to correspond to orthogonalization of the Titulaer-Glauber wave-packet modes. The wave functions of PWM and mode functions of QFT are shown to be equivalent, evolving via identical equations of motion, and completely describe photonic states. We generalize PWM to two or more photons, and show how to switch between the PWM and QFT viewpoints. The second-order coherence tensors of classical coherence theory and the two-photon wave functions are shown to propagate equivalently. We give examples of beam-like states, which can be used as photon wave functions in PWM, or modes in QFT. We propose a practical mode converter based on spectral filtering to convert between wave packets and their corresponding biorthogonal dual wave packets.
Coupled fibers are successfully fabricated by injecting hydrogen flow at 1bar and fused slightly ... more Coupled fibers are successfully fabricated by injecting hydrogen flow at 1bar and fused slightly by unstable torch flame in the range of 800-1350 o C. Optical parameters may vary significantly over wide range physical properties. Coupling coefficient and refractive index are estimated from the experimental result of the coupling ratio distribution from 1% to 75%. The change of structural and geometrical fiber affects the normalized frequency (V) even for single mode fibers. Coupling ratio as a function of coupling coefficient and separation of fiber axis changes with respect to V at coupling region. V is derived from radius, wavelength and refractive index parameters. Parametric variations are performed on the left and right hand side of the coupling region. At the center of the coupling region V is assumed constant. A partial power is modeled and derived using V, normalized lateral phase constant (u), and normalized lateral attenuation constant, (w) through the second kind of modified Bessel function of the l order, which obeys the normal mode, LP 01 and normalized propagation constant (b). Total power is maintained constant in order to comply with the energy conservation law. The power is integrated through V, u and w over the pulling length range of 7500-9500µm for 1-D where radial and angle directions are ignored. The core radius of fiber significantly affects V and power partially at coupling region rather than wavelength and refractive index of core and cladding. This model has power phenomena in transmission and reflection for industrial application of coupled fibers.
Ülkelerin ekonomik büyüme ve kalkınma sürecindeki temel prensip ülkenin mevcut kaynak ve imkânlar... more Ülkelerin ekonomik büyüme ve kalkınma sürecindeki temel prensip ülkenin mevcut kaynak ve imkânlarını rasyonel ve verimli biçimde kullanmasına bağlıdır. Kadın işgücü, ülke üretiminin en önemli kaynaklarından ve ülke kalkınmasında lokomotif görevi olan bir faktördür. Kadının işgücüne katılımının artması, hem ekonomik büyümeyi hem de kadının toplum ve aile içindeki statüsünü olumlu yönde etkileyerek toplumun sosyal ve kültürel gelişmesinde önemli katkılar sağlar.
Fiber coupler fabrication used for an optical waveguide requires lossless power for an optimal ap... more Fiber coupler fabrication used for an optical waveguide requires lossless power for an optimal application. The previous research coupled fibers were successfully fabricated by injecting hydrogen flow at 1 bar and fused slightly by unstable torch flame in the range of 800–1350°C. Optical parameters may vary significantly over wide range physical properties. Coupling coefficient and refractive index are estimated from the experimental result of the coupling ratio distribution from 1% to 75%. The change of geometrical fiber affects the normalized frequency V even for single mode fibers. V is derived and some parametric variations are performed on the left and right hand side of the coupling region. A partial power is modelled and derived using V, normalized lateral phase constant u, and normalized lateral attenuation constant, w through the second kind of modified Bessel function of the l order, which obeys the normal mode and normalized propagation constant b. Total power is maintained constant in order to comply with the energy conservation law. The power is integrated through V, u, and w over the pulling length of 7500 µm for 1-D. The core radius of a fiber significantly affects V and power partially at coupling region rather than wavelength and refractive index of core and cladding. This model has power phenomena in transmission and reflection for an optical switch and tunable filter.
Plant breeding for organic agriculture (OA) was stimulated when it came under the European Organi... more Plant breeding for organic agriculture (OA) was stimulated when it came under the European Organic Agriculture Regulation (2092/91) in 2004. In Brittany, the need for specific varieties for organic farming arose early for the Brassica species because of the unsuitability of most of the modern varieties to the principles of OA. Moreover, the private sector of plant breeding finds it economically difficult to satisfy the demands of OA. The aim of the present study is to provide varieties and seed for organic farmers for two vegetable Brassica crops, and to show how genetic resources can contribute to this purpose in the framework of a Participatory Plant Breeding (PPB) programme. The emergence of PPB in Brittany is the result of several concomitant and favourable circumstances: the will of the professionals (represented by IBB, Inter Bio Bretagne), their organization (an experimental station, the PAIS, Plateforme Agrobiologique d’IBB à Suscinio), the research initiative in INRA and the availability of genetic resources. From genetic resource observations, our experience showed several breeding situations: reviving a traditional activity (Roscoff cauliflower and local cabbages), extending tradition (autumn cauliflower), diversifying production by new introductions (coloured cauliflowers), and creating new forms of population varieties (broccoli and coloured cauliflowers). Farmers have taken charge of population breeding by mass selection and the PAIS, with INRA scientific support, has taken up innovative selection and the improvement of varieties completing the farmers’ initiatives. The PAIS remained the central point for information and for providing the seed for trials. Seed production will be managed in a collective way. Until now, the exchange of seed remained an experimental dimension of PPB. French seed legislation represents a limitation on the development of seed exchange by PPB.
A method for making early mode decisions in an H.264 coder is presented. Significant computation ... more A method for making early mode decisions in an H.264 coder is presented. Significant computation savings can be achieved, since the proposed algorithm can estimate whether the coder would choose to skip, that is, transmit minimal information, for the current macroblock without explicitly coding the macroblock. Estimates are based on coding mode statistics gathered from representative sequences, and results show computation savings of 70-85% for low-activity sequences.
Fabrication of single-mode fiber coupler by heating fibers on a flame is very common and popular.... more Fabrication of single-mode fiber coupler by heating fibers on a flame is very common and popular. However, controlling the input and the output power quantities of the fiber coupling process is neither easy nor similar. Power losses occur at the coupling length as the effect of the geometry and structure of fibers during and after fusion. In application, the power losses will affect sensor devices, eg optical switch. This paper proposes power splitting into the second fiber junction as a new model by deriving and integrating the coupling power with ...
We propose a simple kinetic model that can be used to improve the coupling coefficient value of a... more We propose a simple kinetic model that can be used to improve the coupling coefficient value of a single mode fiber coupler in the fabrication process. The proposed model is time independent, where the internal and external parametric functions are included. The simulation is integrated over the coupling ratio range for the various fiber separations. The coupling coefficient value of the device is examined by using the coupling ratio range from 1% to 75%. The result obtained is compared with the experimental results, where it is ...
Journal of Engineering, Design and Technology, 2009
Purpose A literature review is presented in the subject of construction plant and equipment man... more Purpose A literature review is presented in the subject of construction plant and equipment management (CPeM) to: delineate the subject; consider its development over recent years; and identify principal themes within it. The paper aims to close the gap in knowledge, by using ...
Incoherent broad-band cavity-enhanced absorption spectroscopy (IBB-CEAS) based on arc lamps has b... more Incoherent broad-band cavity-enhanced absorption spectroscopy (IBB-CEAS) based on arc lamps has been around for a few years, but only two reports exist using light-emitting diodes (LEDs). We present a setup based on a 643-nm LED which is of interest for the simultaneous detection of NO3 and NO2. The latter is chosen for testing as it is stable and available in calibrated diluted samples. A detection limit in the ppbv range is obtained with 2-min averaging (5×10-9 /cm rms baseline noise level), comparable to the best performance of chemiluminescence devices used for pollution monitoring. At 1-s acquisition time, the detection limit is below 10 ppbv. Extrapolation to NO3 yields a detection limit of a few pptv for a few minutes averaging. We also test the retrieval of absolute sample absorption (and concentration) using the cavity mirror reflectivity obtained with a commercial spectrophotometer, and we conclude that a calibration based on a reference sample of known concentration is preferable for accurate concentration measurements with IBB-CEAS. Finally, we present a rigorous frequency-domain derivation of cavity transmission as a function of wavelength for a broad-band spectrally smooth source, which complements the time-domain derivation by Fiedler et al. This derivation exposes an issue with multiple transverse mode excitation inherent to this technique, which may result in slightly distorted spectral profiles.
The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of ele... more The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, that is, by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy-momentum-mass relation, assuming a local energy density. This yields a theory of photon wave mechanics (PWM). The proper Lorentz-invariant single-photon scalar product is found to be non-local in coordinate space, and is shown to correspond to orthogonalization of the Titulaer-Glauber wave-packet modes. The wave functions of PWM and mode functions of QFT are shown to be equivalent, evolving via identical equations of motion, and completely describe photonic states. We generalize PWM to two or more photons, and show how to switch between the PWM and QFT viewpoints. The second-order coherence tensors of classical coherence theory and the two-photon wave functions are shown to propagate equivalently. We give examples of beam-like states, which can be used as photon wave functions in PWM, or modes in QFT. We propose a practical mode converter based on spectral filtering to convert between wave packets and their corresponding biorthogonal dual wave packets.
Coupled fibers are successfully fabricated by injecting hydrogen flow at 1bar and fused slightly ... more Coupled fibers are successfully fabricated by injecting hydrogen flow at 1bar and fused slightly by unstable torch flame in the range of 800-1350 o C. Optical parameters may vary significantly over wide range physical properties. Coupling coefficient and refractive index are estimated from the experimental result of the coupling ratio distribution from 1% to 75%. The change of structural and geometrical fiber affects the normalized frequency (V) even for single mode fibers. Coupling ratio as a function of coupling coefficient and separation of fiber axis changes with respect to V at coupling region. V is derived from radius, wavelength and refractive index parameters. Parametric variations are performed on the left and right hand side of the coupling region. At the center of the coupling region V is assumed constant. A partial power is modeled and derived using V, normalized lateral phase constant (u), and normalized lateral attenuation constant, (w) through the second kind of modified Bessel function of the l order, which obeys the normal mode, LP 01 and normalized propagation constant (b). Total power is maintained constant in order to comply with the energy conservation law. The power is integrated through V, u and w over the pulling length range of 7500-9500µm for 1-D where radial and angle directions are ignored. The core radius of fiber significantly affects V and power partially at coupling region rather than wavelength and refractive index of core and cladding. This model has power phenomena in transmission and reflection for industrial application of coupled fibers.
Ülkelerin ekonomik büyüme ve kalkınma sürecindeki temel prensip ülkenin mevcut kaynak ve imkânlar... more Ülkelerin ekonomik büyüme ve kalkınma sürecindeki temel prensip ülkenin mevcut kaynak ve imkânlarını rasyonel ve verimli biçimde kullanmasına bağlıdır. Kadın işgücü, ülke üretiminin en önemli kaynaklarından ve ülke kalkınmasında lokomotif görevi olan bir faktördür. Kadının işgücüne katılımının artması, hem ekonomik büyümeyi hem de kadının toplum ve aile içindeki statüsünü olumlu yönde etkileyerek toplumun sosyal ve kültürel gelişmesinde önemli katkılar sağlar.
Fiber coupler fabrication used for an optical waveguide requires lossless power for an optimal ap... more Fiber coupler fabrication used for an optical waveguide requires lossless power for an optimal application. The previous research coupled fibers were successfully fabricated by injecting hydrogen flow at 1 bar and fused slightly by unstable torch flame in the range of 800–1350°C. Optical parameters may vary significantly over wide range physical properties. Coupling coefficient and refractive index are estimated from the experimental result of the coupling ratio distribution from 1% to 75%. The change of geometrical fiber affects the normalized frequency V even for single mode fibers. V is derived and some parametric variations are performed on the left and right hand side of the coupling region. A partial power is modelled and derived using V, normalized lateral phase constant u, and normalized lateral attenuation constant, w through the second kind of modified Bessel function of the l order, which obeys the normal mode and normalized propagation constant b. Total power is maintained constant in order to comply with the energy conservation law. The power is integrated through V, u, and w over the pulling length of 7500 µm for 1-D. The core radius of a fiber significantly affects V and power partially at coupling region rather than wavelength and refractive index of core and cladding. This model has power phenomena in transmission and reflection for an optical switch and tunable filter.
Plant breeding for organic agriculture (OA) was stimulated when it came under the European Organi... more Plant breeding for organic agriculture (OA) was stimulated when it came under the European Organic Agriculture Regulation (2092/91) in 2004. In Brittany, the need for specific varieties for organic farming arose early for the Brassica species because of the unsuitability of most of the modern varieties to the principles of OA. Moreover, the private sector of plant breeding finds it economically difficult to satisfy the demands of OA. The aim of the present study is to provide varieties and seed for organic farmers for two vegetable Brassica crops, and to show how genetic resources can contribute to this purpose in the framework of a Participatory Plant Breeding (PPB) programme. The emergence of PPB in Brittany is the result of several concomitant and favourable circumstances: the will of the professionals (represented by IBB, Inter Bio Bretagne), their organization (an experimental station, the PAIS, Plateforme Agrobiologique d’IBB à Suscinio), the research initiative in INRA and the availability of genetic resources. From genetic resource observations, our experience showed several breeding situations: reviving a traditional activity (Roscoff cauliflower and local cabbages), extending tradition (autumn cauliflower), diversifying production by new introductions (coloured cauliflowers), and creating new forms of population varieties (broccoli and coloured cauliflowers). Farmers have taken charge of population breeding by mass selection and the PAIS, with INRA scientific support, has taken up innovative selection and the improvement of varieties completing the farmers’ initiatives. The PAIS remained the central point for information and for providing the seed for trials. Seed production will be managed in a collective way. Until now, the exchange of seed remained an experimental dimension of PPB. French seed legislation represents a limitation on the development of seed exchange by PPB.
A method for making early mode decisions in an H.264 coder is presented. Significant computation ... more A method for making early mode decisions in an H.264 coder is presented. Significant computation savings can be achieved, since the proposed algorithm can estimate whether the coder would choose to skip, that is, transmit minimal information, for the current macroblock without explicitly coding the macroblock. Estimates are based on coding mode statistics gathered from representative sequences, and results show computation savings of 70-85% for low-activity sequences.
Fabrication of single-mode fiber coupler by heating fibers on a flame is very common and popular.... more Fabrication of single-mode fiber coupler by heating fibers on a flame is very common and popular. However, controlling the input and the output power quantities of the fiber coupling process is neither easy nor similar. Power losses occur at the coupling length as the effect of the geometry and structure of fibers during and after fusion. In application, the power losses will affect sensor devices, eg optical switch. This paper proposes power splitting into the second fiber junction as a new model by deriving and integrating the coupling power with ...
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