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An optical signal generator for telecommunication systems, comprising at least a single-frequency active optical fiber laser as an optical signal source at a signal transmission wavelength, at least an active optical fiber optical amplifier operatively connected to said laser and at least one source of pumping optical power at a pumping wavelength, the pumping optical power source being operatively connected to at least one of said active fibers of said laser and amplifier and transfer-means for said pumping optical power being connected to said active fibers of said laser and amplifier, in order to transfer unabsorbed optical power at the pumping wavelength from one of said active fibers to the other of said active fibers.
1. An optical signal generator comprising:
a continuous wave coherent optical signal source and an optical amplifier operatively connected to said source for amplifying optical signals received by said optical amplifier from said source;
said source comprising an optical fiber laser oscillator including a first active optical fiber having a core doped with a fluorescent substance, said fluorescent substance having laser emission at an emission wavelength and light absorption at a pumping wavelength different from said emission wavelength;
said optical amplifier comprising a second active optical fiber having a core doped with a fluorescent substance having laser emission at said emission wavelength and light absorption at said pumping wavelength;
a source of pumping optical power at said pumping wavelength operatively connected to at least one of said first and said second active optical fibers for supplying pumping optical power to said at least one of said first and second active fibers; and
selective transfer means for said pumping optical power, said transfer means being operatively connected to said first and said second active optical fibers to transfer non-absorbed optical power at said pumping wavelength from one of said first and second active optical fibers to the other of said first and second active optical fibers.
2. An optical signal generator according to claim 1 wherein said transfer means comprises:
a first and a second selective dichroic coupler, each coupler having three optical input/output branches, a first one of said branches of said first coupler being operatively connected to an end of said first active optical fiber for conveying signals at said emission wavelength and at said pumping wavelength, and a first one of said branches of said second couplers being operatively connected to an end of the second active optical fiber for conveying signals at said emission wavelength and at said pumping wavelength, a second one of said branches of said first coupler being operatively connected to a second one of said branches of said second coupler for conveying signals at said emission wavelength from said first coupler to said second coupler, and a third one of said branches of said first coupler, being operatively connected to a third one of said branches of said second coupler by optical conduction means for conveying luminous emission at said pumping wavelength between said laser oscillator and said optical amplifier.
3. The optical signal generator according to claim 1, wherein said optical power supply means is connected to said first active optical fiber.
4. The optical signal generator according to claim 1, wherein said optical power supply means is connected to said second active optical fiber.
5. The optical signal generator according to claim 1, wherein said source of pumping optical power is connected to said first active optical fiber, and further comprising a second source of pumping optical power connected to said second active optical fiber.
6. The optical signal generator according to claim 1, wherein said source of pumping optical power is connected to the end of said second active optical fiber farthest from said continuous wave coherent optical signal source.
7. The optical signal generator according to claim 1, wherein said core of said first active optical fiber and said core of said second active optical fiber are doped with at least one fluorescent substance which is the same for both said core of said first optical fiber and said core of said second optical fiber.
8. The optical signal generator according to claim 7, wherein said at least one fluorescent substance is erbium.
9. The optical signal generator according to claim 1, wherein said core of said first active optical fiber and said core of said second active optical fiber are doped with alumina as a refraction index modifier.
10. The optical signal generator according to claim 2, further comprising a width modulation means interposed between said continuous wave coherent optical signal source and said optical amplifier for modulating said optical signals at said emission wavelength received by said optical amplifier from said continuous wave coherent optical signal source.
11. The optical signal generator according to claim 10, further comprising an optical isolator interposed between said continuous wave coherent optical signal source and said width modulation means for allowing light propagation substantially only in one direction from said continuous wave coherent optical signal source to said optical amplifier.
12. The optical signal generator according to claim 1, wherein said optical amplifier has an output for providing amplifier optical signals and further comprising an optical isolator connected to said output for allowing light propagation substantially only in the direction away from said output.
13. The optical signal generator according to claim 8, wherein said emission wavelength is within a band between 1530 and 1550 nm.
14. The optical signal generator according to claim 8, wherein said pumping wavelength is 980 nm.
1. Field of the Invention
The present invention relates to a high-power optical signal generator including at least a laser as the signal source and at least an optical amplifier operatively connected to the laser. The invention is particularly suitable for telecommunication equipment, such as cable television. (CATV) and signal distribution networks.
2. Background and Objects of the Invention
At present, high-power and high-speed transmissions are limited by the maximum power of single-frequency semiconductor lasers of the DFB (distributed feed-back) type used as signal sources. In particular, it is difficult to realize semiconductor lasers which have an output above 2-4 mW and which are reliable. Furthermore, if bias current is commutated or modulated at a high modulation speed in such lasers, the fast current changes cause a change in the frequency of the light emitted by the device. When the signal then propagates in a dispersive means (such as an optical fiber), these frequency changes turn into propagation time variations and the quality of the received signal is degraded.
If the laser operates with continuous wave (CW) and an external width modulator is positioned downstream, however, the frequency noise problem is eliminated. Nevertheless, the width modulator, generally an integrated optics passive device, causes an additional loss due to the coupling losses which take place owing to light transition from an optical fiber to a wave guide of the modulator and vice versa.
These losses involve a power penalization of 3-4 dB, further reducing the available optical power.
The use of an amplifier placed downstream of the modulator in order to increase output power to 20-40 mW is described in PROCEEDINGS ECOC '91, (Post-Deadline Paper), pages 72-75, from P.M. Gabla et al.
In this document an experiment is described using a DFB laser transmitter connected to a Mach-Zender external modulator and an erbium-doped optical fiber postamplifier (EDFA) in order to raise the signal level up to +12 dBm. However, the transmission path of the described device goes through 26 sections, each one including one erbium doped optical fiber amplifier (EDFA) and one fiber coil.
Also, the DFB laser used in the experiment had emission at a wavelength of 1553 nm, while the maximum absorption of the amplifier fiber was at a wavelength of 1533 nm.
Furthermore, in OFC '92, pages 242, 243 (Y.K. Park et al.) a long distance transmission experiment is described in which a DFB laser at 1558 nm wavelength emission was connected to a Mach-Zender external modulator and then to a power amplifier. The described device had a series of two connected erbium doped optical fiber amplifiers (EDFA), each one of them with bidirectional pumping.
In order to obtain the better performances of the amplification stage connected to the laser, and of the line amplifiers, the emission wavelength of the continuous wave laser must be fitted as much as possible to the gain peak wavelength of the amplifier, which, if carried out in a fiber made of silica doped with erbium, has wavelength values of about 1531 or 1536 nm, which is related to the dopant, e.g., germanium or alumina, which is used to modify the refraction index of the fiber core.
In order to satisfy this requirement, it is necessary to use a DBF laser at a selected wavelength but this involves, among other things, manufacturing difficulties and a significant increase in cost.
The known structure also has drawbacks, due, among other things, to the requirement of limiting the noise generated by the amplifier, which is particularly critical for some applications and which requires the maintenance of a high pumping power level along the whole fiber. This condition requires, on the one hand, feeding high pumping power to the fiber, thus reducing the amplifier efficiency, and on the other hand, having high power pumping lasers which have a reduced reliability.
In order to supply such high pumping power, pumping splitting and multi-stage amplifications may also be required, which makes the structure more complex and affects the whole efficiency: for instance, Y. Park et al. in OFC '92 describe the use, as a power amplification unit, of two fiber amplifiers, each of them pumped with two pumping lasers having powers respectively of 15.3 dBm and of 17.3 dBm, for an output power of 16 dBm.
There are also known laser fibers, doped with erbium, as described in PROCEEDINGS ECOC '91, pages 149-152 by G. Grasso et al. Such lasers, nevertheless, require the use of a diode pumping laser, which is commercially available with emission powers which are not optimal for fiber laser operation, so that the fiber laser has limited efficiency, particularly for the aforesaid uses in telecommunications.
It has been found that the combination of a fiber laser and a fiber amplifier, in which the pumping power is shared between the laser and the amplifier, allows the achievement of high efficiency and low noise generation, overcoming the typical limits of the known solutions and of the single components.
An object of the present invention is, therefore, to provide a high power optical signal generator, particularly for telecommunications use, which has high efficiency, reliability and low cost.
Accordingly, the invention relates to an optical signal generator comprising a continuous wave, coherent, optical signal source and an optical amplifier, operatively connected to said source for the amplification of the optical signals, wherein:
said source is constituted by an optical fiber laser oscillator, comprising an active fiber having core doped with a selected fluorescent substance having laser emission at an emission wavelength and light absorption at a pumping wavelength different from said emission wavelength; said amplifier comprising an active optical fibre having core doped with a selected fluorescent substance having emission at said emission wavelength and light absorption at said pumping wavelength; and
a pumping optical power supply means at said pumping wavelength.
characterized in that:
said pumping optical power supply means is operatively connected to at least one of said active fibers of said laser oscillator and said amplifier; and
a selective transfer means for said pumping optical power is operatively connected to said active fibers of said laser oscillator and said amplifier, in order to transfer non-absorbed optical power at the pumping wavelength from one of said active fibers to the other of said active fibers.
According to a preferred embodiment, said transfer means comprises selective dichroic couplers between said emission wavelength and said pumping wavelength, said couplers having three optical input/output branches, including:
a first branch, which jointly carries optical signals at the emission wavelength and at the pumping wavelength, is respectively connected to an end of said active optical fiber of said laser oscillator and of said active fiber of said amplifier;
a second branch, which carries optical signals at the emission wavelength, is operatively connected to conduct between the input and output of said second branch; and
a third branch, which carries optical signals at that pumping wavelength, is connected between the first and second branches through a by-pass optical conduction means and said active fiber amplifier for the luminous emission transfer at said pumping wavelength between said laser oscillator and amplifier.
Advantageously, said active fibers of said laser and amplifier have core doped with at least a same fluorescent substance, namely erbium.
Features and advantages of the invention will be now illustrated with reference to preferred embodiments, represented by way of non-limiting examples, in the accompanying drawings, wherein:
FIG. 1 is a schematic representation of a first embodiment of an optical signal generator;
FIG. 2 is a schematic representation of a second embodiment of an optical signal generator;
FIG. 3 is a combined schematic representation of the generator of the invention and the variation of partial and total pumping powers along the optical signal generator.
FIG. 1 illustrates a high power signal optical generator 1 including a single-frequency continuous wave (CW) laser oscillator 2, which constitutes an optical signal source at emission wavelength, and an amplifier 3.
Reference numeral 4 designates a connection line between said generator 1 and said amplifier 3 and includes an optical fiber 7, an optical isolator 5 and a width modulator 6 of the generator signals, for example, a Mach-Zender modulator.
An optical isolator 8 disposed downstream of the amplifier 3 and an optical output fiber 9 from the generator 1, connect, through an optical fiber 10, to a receiver 11 of the output signals from generator 1.
The laser generator 2 active means is constituted by an active optical fiber 12 including a refraction index modifier, preferably, alumina, germanium or alumina and germanium, and having core doped with at least a selected, fluorescent substance, preferably, erbium.
The active fiber 12 has an upstream end 13 connected to an output 14 of a dichroic coupler 15 having an input 16 connected to a pump laser 17, able to supply pumping power at pumping wavelength. An input 18 of said coupler 15 is connected to an output 19 of a directional coupler 20, which is connected to the ends of a wide-band reflector 21, which, in the described embodiment, is a reflection ring 29 able to reflect the whole emission spectrum of the active fiber 12, or at least its part of interest for the transmission.
In another version, the wide-band reflector 21 could be a metal coating (plating) of the terminal surface of the fiber 12, or even by a wide-band Bragg grating reflector.
The active fiber 12 has a downstream end 22 connected to an input 23 of a dichronic coupler, or multiplexer, 24 with three optical input/output branches, the output 25 of which is connected to a narrow-band, selective reflector 27, able to reflect a band of a width which is less than 0.5 nm and preferably, less than 0.1 nm of the active fiber 12 emission spectrum, and which is, preferably, a Bragg grating optical fiber reflector, or a Fabry-Perot interferometer with "GRIN" lens (abbreviation for "graded index", or gradually variable refraction index), acting as a narrow-band reflector. The reflector 27 is connected to the line 4, an output 26 of the coupler 24 is connected to a branching off fiber 28, at the pumping wave-length, a longitudinal single-mode (monomodal) "by-pass" fiber, in parallel to said connection line 4.
A fiber laser using a grating reflector is, for example, described in "Electronics Letters", vol. 24, Nr. 1, 7 Jan. 1988.
A fiber laser operating at longitudinal single-mode, by means of a Fabry-Perot interferometer with "GRIN" lens is described in "PROCEEDINGS ECOC 1991", pages 149-152.
A Fabry-Perot interferometer is commercially available. The structure of an interferometer with GRIN lens, known in itself, is described in particular in the aforesaid article.
The Bragg grating reflector is constituted by an optical fiber whose cladding and core are partly removed for a length, forming a surface on which, by means of a photochemical process, several parallel lines are realized having pitch Λ which is related to the reflected wavelength by the relation l=2 ne Λ, wherein ne is the effective mode refraction index of said fiber. Therefore, the grating pitch is related to the emission bandwidth of the laser 2.
The Bragg reflector features are not further described in detail because it is known and commercially available.
The amplifier 3 comprises an optical active fiber 30, including a refraction index modifier, preferably, constituted by alumina, germanium or alumina and germanium, and having core doped with at least a selected fluorescent substance, also preferably, erbium.
Preferably, the amplifier active fiber is a fiber having the same features as the laser oscillator active fiber. In particular, it is favorable that the fluorescent dopant and the one or more index modifier dopants are the same, or are anyway chosen so that the laser emission spectrum is as much as possible equal to that of the amplifier (within the band of considered wavelengths), so as to have the laser emission at the wavelength of maximum gain for the amplifier, thus obtaining the best system efficiency.
The active fiber 30 has an upstream end 31 connected to an output 32 of a dichroic coupler, or multiplexer, 33, the inputs of which, 34 and 35, are respectively connected to the line 4 and to the by-pass fiber 28.
A downstream end 36 of the active fiber 30 is connected to an input 37 of a dichroic coupler 38, the outputs of which, 39 and 40, are respectively connected to said optical isolator 8 and to a pump laser 41, able to supply pumping power at the aforesaid pumping wavelength, supplying the active fiber 30 from its downstream end, counter-current with respect to the direction of the path of the optical signal within the amplifier 3.
The optical general 1 works as follows:
The active fiber 12 of the laser 1 receives pumping energy at the pumping wavelength, which is therein absorbed giving rise to a laser transition with light emission at the emission wavelength, which is amplified in consequence of reflections due to reflectors placed at the ends of the fiber itself, giving rise to a coherent light emission. Such emission is sent through the optical isolator 5, to the modulator 6 and then, to the amplifier 3.
The modular 6 converts the continuous emission of the laser 2 into a modulated optical signal.
The amplifier 3, the active fiber of which is maintained in a population inversion state (namely, excited at a laser emission level) by the pumping power therein absorbed, amplifies the signal, up to a power level which is enough to be fed into the output optical fiber 9 and to reach the receiver 11 through the fiber 10 maintaining a power level which is large enough to be useful, even after the attenuation introduced by the fiber 10 itself, which in the practical application may have a considerable length, for example dozens or hundreds of kilometers. The pump laser 17 of the laser oscillator 2 is selected to generate optical power in excess of that absorbed by the active fiber 12 for reasons which will be hereafter illustrated. The unabsorbed residual optical pump power at the end 22 of the fiber 12 itself is transferred to the active fiber 30 of the amplifier 3 by means of the couplers 24, 33 and the by-pass fiber 28.
Similarly, the pump laser 41 of the amplifier 3 is selected to generate optical power in excess of that absorbed by the active fiber 12. The residual excess of pumping power at the end 31 of the active fiber 30 of the amplifier 3 is transferred to the active fiber 12 through the same couplers 24, 33 and the same by-pass fiber 28.
In accordance with the invention, an optical generator according to the illustration in FIG. 1., has been made and had the following features.
Laser 2 in the described example had an active fiber 12 having core doped with erbium and has the following features:
______________________________________fiber length 5 mfiber type Si/Alnumerical aperture NA = 0.19cut off wavelength lc = 900 nmerbium content in the core Nt = 5.8 � 1024 ions/m3pumping section sp = 2.8 � 10-25 m2______________________________________
The pump lasers 17 and 41 were lasers of a type known as "Strained Quantum Well" with the following features:
______________________________________emission wavelength lp = 980 nmoutput power Pu = 80 mW______________________________________
Lasers of the specified type are, for instance, produced by David Sarnoff Research Center, Washington Rd., Princeton, N.J. (USA).
The reflection ring 21 was formed with about 50 cm of monomodal optical fiber at the signal wavelength.
The directional coupler 20 has power division ratio of 50/50 and is of commercial kind, as, for instance, model 1550 POH 50/50 2�2 produced by Gould Inc., Fiber Optic Division, Baymeadow Drive, Glem Burnie, Md. (USA).
Dichroic couplers 15 and 24 which were used, were melted fiber couplers consisting of two monomodal fibers at 980 nm and 1531 nm wavelength, with variation of output optical power as a function of the polarization, lower than 0.2 dB, so as to avoid emission instability, in the presence of thermal variations or mechanical stresses which cause a variation in the emission polarization of the pump laser 17.
Dichroic couplers of the indicated kind are produced, for instance, by Gould Inc., Fiber Optic Division, Baymeadow Drive, Glem Burnie, Md. (USA), and by Sifam Ltd., Fibre Optic Division, Woodland Road, Torquay, Devon (GB).
The output fiber 25 of the coupler 24 is traversed by light at 1531 nm wavelength, while the by-pass fiber 28 is traversed by light at 980 nm wavelength.
The Bragg grating selective reflector 27 used had the following features:
______________________________________reflectivity 35%reflected bandwidth l = 1531 nmband width 0.7 nm______________________________________
Reflectors of this kind are marketed by United-Technologies Photonics, Silver Lane, East Hartford, USA.
The modulator 6 is an intensity modulator based on a wave guide version of a Mach-Zender interferometer, of a commercial kind, with a band width in linear field of 3 GHz, with minimal extinction ratio of 22 dB and suitable for working within the wavelength band of 1530-1550 nm. The modulator used was model MZ315P produced by Crystal Technology, Inc., 1060 East Meadow Circle, Palo Alto, Calif., USA.
The active fibers 30 of the amplifier 3 with the core doped with erbium had the following features:
______________________________________fiber length 12 mfiber kind Si/Alnumerical aperture NA = 0,19cut off wavelength lc = 900 nmerbium content in the core Nt = 5.8 � 1024 ions/m3pumping section sp = 2.8 � 10-25 m2.ls1______________________________________
The described generator had the following features:
______________________________________total pumping optical power 160 mWlaser pumping optical power 80 mWamplifier pumping optical power 80 mWresidual pumping power in the laser 20 mWresidual pumping power in the amplifier 15 mWsignal power at the laser output 3 mW (5 dBm)signal power after modulation about 1 mW (0 dBm)signal power after amplification 45 mW (16 dBm)______________________________________
The laser 2 illustrated in FIG. 1 is provided with a steady wave resonant cavity, but other cavity architectures may be used. For instance, a ring cavity incorporating a reflection grid, as in the optical generator of FIG. 2.
In the version of the optical generator shown in FIG. 2, the elements common with those of FIG. 1 are indicated with the same reference numbers. The optical signal generator 50, includes a single-frequency continuous wave laser 51 and an amplifier 3.
The laser 51 is constituted by an active fiber 12, for instance, of the same kind as the fiber in FIG. 1, by a dichroic coupler 15 connected through an optical fiber 16 to a pumping laser 17, and by a reflecting optical fiber 56 provided with an optical isolator 57. The reflecting fiber 56 is connected to a directional coupler 58 to which is connected an optical fiber 59 which, in turn, is connected to a dichroic coupler 24. The coupler 24 is connected to the active fiber 12 and to the by-pass optical fiber 28. An output 61 of the directional coupler 58 is connected to the selective grid reflector 27.
In the FIG. 2 embodiment, the light emission at 1531 nm generated by the fiber laser 51 propagates through the optical isolator 5 and the width modulator 6, entering the fiber amplifier 3, pumped by way of a coupler 33, and is then transmitted to the receiver 11, as in the optical generator 1 of FIG. 1.
Likewise, the excessive pump power of one or of the other pump laser 17, 41 is transferred either to the active fiber 30 or to the active fiber 12.
The directional coupler 58 has a division ratio of 50/50 and shares, with this ratio, between the fibers 56 and 59, the light beam power reflected by the selective reflector 27.
In the aforedescribed optical generators 1 and 50, the laser resonant cavity is deliminated by the ring of the reflection fiber 21 or by the reflection fiber 56 (or by another wide band equivalent mirror) acting as high laser reflector, and by a grid reflector 27 acting as an output coupler with an extremely narrow reflection band.
The pumping energy generated by the pump laser 17 is fed through the respective coupler 15 to the erbium doped fiber 12, which constitutes the active means of the laser source.
Within the laser cavity is present a dichroic coupler 24 able to convey to the active fiber 12, the pump energy coming from the amplification stage 3 through the pump by-pass 28.
The single-frequency laser 2 or 51 with erbium doped active fiber 12 is connected with an amplification stage 3 with an ermium doped active fiber 30. The fiber laser emission coincides with the gain peak of the amplifier fiber. This assures the most efficient amplification of the light produced by the fiber laser.
The laser single-frequency operation is obtained with the use of the grid reflector 27 with narrow-width band, typically less than or equal to 0.1 nm, using the spectral selectivity of the periodical structure of the reflector grid and the mode competition due to the different reflection efficiency at the different frequencies within the reflector reflection band, which penalizes the wavelength modes different from that of maximum reflection within the band, and which are subjected to higher losses and do not reach the laser operating threshold.
A laser of this kind is described, for instance, in the aforesaid article "Electronics Letters", pages 24-26, vol. 24, N. 1, 7 Jan. 1988.
The presence of residual pumping power at the end of the laser 2 active fiber and of the amplifier 3 is related to the particular kind of fluorescent dopant therein used, preferably, erbium.
In fact erbium, present as a dopant in the fiber core in the form of Er3+ ions, forms a so-called "three levels" emission system, wherein the pumping energy fed in the fiber is absorbed and excites Er3+ ions from the base level to an energy band, a so-called "pumping band", from where they fall, in not a radiative way, to an excited level, a so-called "higher laser level", where they can rest for a certain time before spontaneously falling again to the base level.
The photon passage at the same wavelength corresponding to said laser level causes a transition of the erbium ion to the base level, followed by the emission of a new photon, coherent with the first and having the same wavelength.
Such phenomenon allows the generation of a signal due to spontaneous emission and its coherent amplification, caused by multiple reflections in a laser oscillator, like the laser 2, and the amplification of an output signal which is fed to the fiber amplifier 3.
In the presence of erbium ions at a base level, on the contrary, a photon at the wavelength corresponding to the aforesaid laser emission level is absorbed, exciting a corresponding erbium ion at the laser level, and hence, causing a signal attenuation.
Therefore, in order to have a signal emission or amplification, it is necessary that along the whole active fiber length, the pumping power is higher than a certain level, or "threshold level", at which erbium ions at the higher laser level are of the same number than the ones at the base level, so that the amplification effect due to erbium ions excited at laser level compensates the attenuation effect due to erbium ions at base level, in this way realizing the so-called fiber "transparency".
In an active fiber, the threshold power value depends on the dopant (erbium) content therein. By way of example, in the active fiber of the example of FIG. 1, the threshold power is 5 mW.
For various reasons, in addition, it is preferable to maintain even at the active fiber end, opposite to that of pumping energy input, a residual pump power value not only equal, but even higher by a certain value than the aforesaid threshold value. In this way, at the end of the active fiber opposite from the pump power input end, there still remains an amount of pumping optical power, at least equal to the aforesaid "threshold" value.
The need to maintain a high pump power level even at the extreme end section of the active fiber is particularly important in the amplifier, wherein it has been observed that the "noise" due to the same amplifier rises considerably when pumping power has a minimum value in the fiber close to the "threshold" power, with respect to a situation in which the minimum value of the pumping power in the fiber is enough greater than the "threshold" power.
The "noise" is in fact proportional to the atomic population in the higher laser level and decreases less rapidly than the gain along the fiber with the pumping power decreasing within the fiber itself.
FIG. 3 shows the variation of the pumping power Pp supplied in the respective active fibers 12 and 30 of the laser and of the amplifier, as a function of the length 1f of the fibers themselves. The broken line P1 indicates the pump power due only to the pump laser 17, and the dotted line P2 indicates the pump power due only to the pump laser 41.
The continuous line P shows the whole pump power in the fibers, due to the contribution of both the pump lasers.
As shown by the previously related experimental data, without "by-pass", the pump power supplied by the pump laser 17, not absorbed by the doped fiber 12 and present at its end 22, has a considerable magnitude, equal to 20 mW in the example given. In the amplifier, in its turn, the residual pumping power at the end 31 of the fiber 30 has a value equal to about 15 mW.
In the amplifier, especially, such residual power level would be excessively low, such as to cause an unacceptable high noise level in the emitted signal. A minimal acceptable value of residual pump power in the amplifier fiber is higher than 25-30 mW.
With 15 mW of residual minimum pump power in the amplifier fiber, one can estimate a noise figure, defined as (S/N)i /(S/N)o, higher than 4.8 dB where (S/N)i is the ratio between the signal power and the noise power at input in the amplifier and (S/N)o is the ratio between the signal power and the noise power at output from the amplifier.
Therefore, the residual pump power transfer from the one to the other of the active fibers allows as is shown by FIG. 3 (which schematically represents the phenomenon) to retain, particularly in the amplifier 3, a pump power level never less than 35 mW, which provides particularly low noise values. In the described experiment, a noise figure equal to about 3.8 dB was obtained.
Such performance, without pump power transfer, would require much higher power values of the laser 41, for example, about 100 mW, as shown in FIG. 3 by broken line P3, which can be obtained with a laser much more expensive and less reliable due to the high power required.
The structure according to the invention, in addition, prevents any dissipation of residual pump power, which has not been absorbed in the active fiber of the laser 2, for which it would not be practical to use a pump laser of an excessively low power which would be suitable only for the requirements of the laser 2 itself.
Modulator 6, which as it has been said, is preferably a Mach-Zender modulator, in LiNbO3, is placed upstream of the amplifier 3, in order to avoid "photorefractive" damaging risks of the wave guide of said modulator, due to the high power involved (more than 10 mW), that would arise if it were disposed to modulate an already amplified signal. High optical signal powers may generate the formation of coupled electron-holes in the wave guide structure, which would change the light propagation.
In the example illustrated, the generator 1 includes the pump lasers 17 and 41, but a generator according to the invention may be equipped either only with the pump laser 17 or only with the pump laser 41, because the by-pass optical fiber 28 allows the transfer of the excess pump power, in the first case, to the active fiber 30 of the amplifier 3, and in the second case, to the active fiber 12 of the laser 2.
Preferably, there are used two equal pump lasers, thereby to obtain higher reliability of the unit, because of the more limited power required from each of them, avoiding the use of high power lasers, that is, it is preferable to resort to use multi-stage or multi-pump structures, without, with this, affecting the system performance.
The pump signal by-pass 28 solution allows a drastic simplification of the architecture of the optical generator, optimizing the use of the available pump power.
In the aforedescribed experimental examples, the amplifier 3 is pumped by a source of pump power 41, through the coupler 38 and the pumping energy propagates counter-current to the laser signal.
Part of the residual pump power not used in the amplifying section of the signal power (amplifier 3) is fed to the laser 2 through the wavelength multiplexer couplers 33, 24, thus contributing to the population inversion of the active section of said laser.
Hence, the excess or residual pump power, not absorbed by the fiber 30 is deviated from the signal path (line 4) by the coupler 33 and is fed back to laser 2 or 51 through the coupler 24.
This solution allows an optimized use of the pump power and a maximization of the total conversion efficiency (pump power with respect to modulated signal power at 1531 nm).
The pump energy by-pass solution may be used even if the pump laser 17 is a high power source and the length of the active fiber 12 is so small that very little pumping power is absorbed therein.
In this case, almost the whole pump power reaches the coupler 24 and is transmitted to the active fiber 30 of the amplifier 3 through the coupler 33.
For some applications, for instance cable television (CATV) and the like, it is particularly important that the laser 2 operation is very steady and without mode jumps.
To this end it is convenient to make use of a cavity-laser of small dimensions, that is to use an active fiber as short as possible, and make the laser 2 operate at rather low signal emission optical power levels, approximately less than 3 mW (5 dBm), and preferably less than 1.5 mW, with the aim to favor single-longitudinal mode (monomode) operation, in which only one frequency is emitted.
In such a case, adopting standard reflectivity values for the selective reflector 27 of 0.4<Rgr<0.6 where Rgr is defined as the ratio between reflected optical power and incident optical power, the total pump power absorbed by the fiber laser preferably does not exceed 15 mW and is advantageously less than 10 mW.
The laser suited to operate in the aforesaid conditions makes use of an active fiber of limited length, of the order of some dozen centimeters, preferably doped with alumina and with a very high erbium content, of the order of 1000 ppm. Therefore, the pump power values supplied to the laser section and to the amplifier will be selected to provide the desired performance.
In the case in which, instead, a high amplification efficiency is desired, for example, for digital transmissions, it is preferable to obtain in the laser a high enough output power, making use of a fiber of substantial length and of high supply of pumping power, as indicated in the example of FIG. 3.
In the case in which active fibers with high numerical aperture (for instance Na>0.3) are used, these would be obtained, both in the laser section and in the amplification section, a high conversion efficiency, near to theoretical values (Pu/Pp=0.48, where Pu is the output signal power, at 1531 nm, and Pp is the pump power, at 980 nm), and hence, it is possible to make use of pump laser whose power is less than the 80 mW used in the system described in the example, (for instance 60 or 40 mW), together with active fibers of less length and/or with different erbium content.
The designing of the laser section and of the amplification section in terms of length and kind of active fiber, based on the specific requirements of each application of the optical generator according to the invention, will be made empirically by the technician on the basis of knowledge in the field.
Preferably the reflectivity value of the width modulator 6 is less than -40 dB in order to avoid, in the amplifier section, the manifestation of spurious oscillations, interferometric noise or amplification efficiency reduction due to exhaustion of the inversion.
It must be noted that the operating wavelength of the system is defined by the reflection features of the selective reflector used. Therefore, this is conveniently chosen so that the reflected wavelength correspond to an emission peak of the used fiber, or anyway to an emission spectrum region at high emission and amplification efficiency.
For instance, in the case of fibers doped with alumina, as in the example described, it is convenient to make use of a selective reflector at a wavelength of about 1531 nm, corresponding to the emission peak of the fiber doped with erbium and alumina.
Dichroic couplers 24, 33 preferably have a selectivity value greater than 20 dB (at each wavelength, the power addressed toward the "wrong" output must be 1% less than the power directed toward the "right" output), with the object of avoiding that spontaneous amplifier emission may arise in the laser, thus compromising the regular operation, or that a fraction of the signal emitted by the laser, and not modulated, may enter the amplifier, thus constituting a noise.
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This set is useful for holding screws into place during fastening. Fixes all screw profiles and sizes securely to the tool. The screw gripper releases the screw after it has been fastened.
22-12340 - Two Piece Screw Gripper Set - 6.5mm-8.0mm / 4.5mm-6mm
22-12345 - Four Piece Screw Gripper Set with PH1 and PH2 Drivers
22-12370 - 30 Piece Wera Bit Ratchet Set
This durable feature rich ratchet set comes with everything you need for your precise applications. This set comes complete with 28 bits, Rapidapter bit holder for fast bit changes, ¼" hex to 1/4"square adaptor for ¼" sockets, and a Wera bit ratchet. Bit adaptor...
22-12400 - 33 Piece Kraftform Kompakt 62 Screwdriver Bit Set
This bit set comes with a Kraftform bit holding screwdriver, Rapidaptor quick release chuck and bits for both manual and machine use. Allows for rapid tool changes for a wide range of applications. Stored in a compact pouch which is handy for storage and use. C...
28-955 - Double Sided Foam Tape
Thousands of uses Fasten accessories to car dash, etc. 3/4" x 61/2' roll
35-5155 - 10MM Headphones White High Performance Earbud
High Performance Earbud Headphones White
Lightweight, stylish, high performance earbuds give crystal clear sound as well as a comfortable fit. Ideal for use with CD, MP3, MP4 and any other small portable audio players.
80-6875 - VHS Head Cleaner
VCR Head Cleaner safely and effectively cleans tape heads and entire tape path Non-abrasive
Exclusive cleaning material prevents debris from re-depositing on heads
Wet type
Great products, fast service, what more could I want.

subset: commoncrawl


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The transaction is expected to close in the fourth quarter of 2012.
Syngenta is one of the world's leading companies with more than 26,000 employees in over 90 countries dedicated to our purpose: Bringing plant potential to life. Through world-class science, global reach and commitment to our customers we help to increase crop productivity, protect the environment and improve health and quality of life. For more information about us please go to www.syngenta.com.
Cautionary Statement Regarding Forward-Looking Statements
This document contains forward-looking statements, which can be identified by terminology such as 'expect', 'would', 'will', 'potential', 'plans', 'prospects', 'estimated', 'aiming', 'on track' and similar expressions.Such statements may be subject to risks and uncertainties that could cause the actual results to differ materially from these statements.We refer you to Syngenta's publicly available filings with the U.S. Securities and Exchange Commission for information about these and other risks and uncertainties.Syngenta assumes no obligation to update forward-looking statements to reflect actual results, changed assumptions or other factors.This document does not constitute, or form part of, any offer or invitation to sell or issue, or any solicitation of any offer, to purchase or subscribe for any ordinary shares in Syngenta AG, or Syngenta ADSs, nor shall it form the basis of, or be relied on in connection with, any contract therefor.
Syngenta International AG
Media Office
CH-4002 Basel
|SOURCE Syngenta
Copyright©2012 PR Newswire.
All rights reserved


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New Video: Chris Brown 'Crawl' – Plus Interview With Wendy Williams
Here is the World Premiere of Chris Brown's new video for Crawl featuring Cassie. Hmmmm…Maybe Cassie sent the text message. I'm just kidding, but I do want to know who sent that text. I don't know why Chris Brown and Rihanna is protecting the privacy of the infamous texter.
Anyway, check out the new video for Crawl…
[Video Credit: Rap Radar]Read More
Rihanna In London Train Station, 50 Cent New Fragrance 'Power'
Rihanna was spotted at St. Pancras International Train Station in London sans makeup, and rocking her shades. I'm not sure why so many people are mad at Rihanna, not sure how getting beat makes you a bad person, but if you read the comments on twitter, you would swear she was a terrorist. (Just because you don't believe her side of the story doesn't mean she wasn't assaulted).
If you weren't on twitter today, then you missed the leak of Rihanna's entire album. I would post the link, but I'm not trying to get shut down.
Also, 50 Cent Launches "Power" Fragrance at Macy's in the Lakewood Mall in Lakewood, CA. Anyone interested in the cologne? I'm scared my husband will start acting like 50 Cent. I am having fun with his new Bill Bixby look, I feel like the Hulk will bust out any moment now…J/K
Read More
Kanye West & Amber Rose In Italy With Matching Clothes
Just when everyone is asking where is Kanye West, he appears with his girlfriend Amber Rose. Are they dressed a like? How cute is that? I guess matching clothes and similar kicks means they are together, at least it does in PR terms. In all honestly, I think they have been on the low so that they can get their privacy back. Kanye West was having a hard time with the paparazzi all in his grill and all in his girl's grill.
Judge To Gucci Mane Go Straight To Jail For 12 Months
I don't know what Gucci Mane has done, all I know is that it violated his probation, and the kind judge sentenced him to 12 months in jail because of his actions. Poor Gucci Mane, he's on every track like Lil Wayne was last year, and now he and Lil Wayne will be serving time. I wonder what the violation was, obviously this story will continued as more information comes in. But for now, MTV reports that Gucci Mane is going to jail for probation violation:
Gucci Mane was sentenced to 12 months in jail on Thursday (November 12) for probation violation and taken away in handcuffs, according to his lawyer.Mane pleaded guilty to assault in 2005 for attacking a nightclub promoter, and last September, he was sentenced to a year in jail for failing to fulfill his court-ordered 600 hours of community service in that case. He went to jail and served until March. Upon his release, Gucci went straight to the studio and recorded five songs.


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The Magpie-goose, Anseranas semipalmata, is a waterbird species found in Australia and New Guinea. It is a unique member of the order Anseriformes, and arranged in a family and genus distinct from all other living waterfowl. The Magpie-goose is a resident breeder in northern Australia and in southern New Guinea.
This family is quite old, having apparently diverged before the Cretaceous–Paleogene mass extinction - the relative Vegavis iaai lived some 68-67 million years ago. The fossil record is limited, nonetheless. The enigmatic genus Anatalavis (Hornerstown Late Cretaceous or Early Paleocene of New Jersey, USA - London Clay Early Eocene of Walton-on-the-Naze, England) is sometimes considered to be the earliest known anseranatid. Other Paleogene birds sometimes considered magpie-geese are the genera Geranopsis from the Hordwell Formation Late Eocene to the Early Oligocene of England and Anserpica from the Late Oligocene of Billy-Créchy (France). The Australian distribution of the living species ties in well with the presumed Gondwanan origin of Anseriformes, but Northern Hemisphere fossils are puzzling. Perhaps the magpie-geese were one of the dominant groups of Paleogene waterfowl, only to become largely extinct later.
This species is plentiful across its range. For Australia as a whole, it is not threatened and has a controlled hunting season when numbers are large. However, most of the southern populations were extirpated in the mid-20th century by overhunting and habitat destruction. The species has been subject to reintroduction projects, and populations have again reached a level where it can be regularly utilized by hunters. In Victoria, the Magpie Goose was listed as near threatened on the 2007 advisory list of threatened vertebrate fauna in Victoria. In the December 2007 Flora and Fauna Guarantee Act list of threatened fauna, it is also listed. As of early 2008, an Action Statement for the recovery and future management of this species had not been prepared.


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By now, you've certainly heard more than enough about the Inaugural Canucks Scrabble Battle. If you recall: a couple weeks back, Tanner Glass and PITB came together for an epic charity Scrabble contest. It was great. The most important thing, of course, is that the event raised $9000 for Canuck Place. The second most important [...]Continue Reading —›
Dan Hamhuis's overtime winner was pure wizardous sedinerie. Rejoice, Canucks fans! Last game wasn't just a triumph, it was a return to form, or at least, something close to it. While the Canucks can say their Nashville game was one of their best, I respectfully disagree — the Canucks aren't at their best playing tight-checking [...]Continue Reading —›
Video from outside Staples Center after the Kings game. Looks like a lot of fun. Fun is good. Wow, it was exhilarating to go to the Ducks game. I met Daniel and Harrison, and their wives, and that was pretty amazing. We were also surrounded by Canucks fans. Living in California, I only see the [...]Continue Reading —›
Here is a video from Canucks.com of Raffi Torres doing a postgame interview with Kristin Reid. It's not interesting. For about twelve seconds, that is. And then, a shirtless Ryan Kesler emerges from behind a curtain, chowing down on some za, altogether too pleased with his lingering, nippletastic, pizza-devouring self. First, he just peers. Then he creeps. He gets progressively closer and closer to Raffi as the video goes on. I imagine he's humming the theme from Jaws the whole time.
And then, after standing directly behind Torres for a full minute, he offers Raffi some pizza. Raffi curtly says "No thanks", and half-naked Kesler disappears from the frame.Continue Reading —›
Canucks 3 – 0 Ducks After the highly contentious atmosphere in the Staples Center last night, the Honda Center was downright pleasant. It's not just that the Anaheim fans are generally more congenial (one woman gave us free hot dogs), but the building itself is a little nicer, a little more organic. Whereas the Staples [...]Continue Reading —›
After spending about twenty hours in the Nissan Versa, bickering about music selection, coining new swear words, and fighting off an invisible army of cramps, well, it was some sort of glorious reprieve to finally get to the hockey portion of the road trip. Not that there weren't highlights en route. For example: Bonnie Tyler's Faster Than [...]Continue Reading —›
Every year, the pundits analyze the winners and losers of the NHL trade deadline, reflecting on the moves made and pointing to organizations that got stronger or weaker, as a result. This convention is valuable, to an extent, but it ignores the smaller effects these trades have on individual dressing rooms. Here in Vancouver, for [...]Continue Reading —›
As you may know, PITB is making the California road trip this year, but we'd hate to leave you with nothing new to peruse in our absence. With that in mind, we'd like to welcome to round three of the Raffi Torres bowling ball photoshop gallery. If you're new to this series, I recommend starting [...]Continue Reading —›
Canucks 0 – 3 Predators The Canucks didn't score, so I used this video from a year ago. With Daniel and Harrison out on a road trip in Oregon, enjoying the thrill of having your gas pumped by someone else, it fell to me to cover this game. Like anyone swapping footwear with Sideshow Bob, [...]Continue Reading —›
When Arsenal lost the League Cup Final to Birmingham last Sunday it began to look as though their hopes of a successful season were beginning to fade. Injuries were piling up, they had a tough game against Barcelona on the horizon and Manchester United were four points clear at the top of the table. The [...]Continue Reading —›
So with the trading deadline come and gone, the Canucks can now proceed with the rest of their record breaking season, a campaign that has them on pace for unprecedented regular season success. There is the opportunity to guarantee home ice advantage for not just the first round, but quite plausibly the entire playoffs. Some [...]Continue Reading —›
Back in January, we posted our second annual Canucks Bandwagon Fan Cheat Sheet, a guide to all of the players on the Vancouver Canucks for the recently baptized Canucks fan. It was an excellent introduction to the team for wives of diehard fans, Vancouverites who just noticed that the Canucks are at the top of [...]Continue Reading —›
Are you going on the Canucks' California road trip? We are! We're looking forward to it too, namely because that many consecutive hockey games simply guarantees that we'll see our fair share of Jersey Fouls. With that in mind, we've created the PITB Jersey Foul Bingo Card, so as to double the joy we derive [...]Continue Reading —›
Canucks 2 – 1 Blue Jackets (SO) It's a shame that the Canucks weren't wearing their retro jerseys, because this game was a total throwback. The team played poorly, showing a complete lack of offensive flair and a general disarray throughout, but thankfully, Roberto Luongo stood tall and singlehandedly kept them in the game. You'd [...]Continue Reading —›
Some have voiced concern over Maxim Lapierre's potential effect on the dressing room. He'll be fine. By now, you're probably aware of deadline acquisitions Chris Higgins and Maxim Lapierre, the two forwards the Canucks picked up at yesterday's trade deadline (and also: MacGregor "NC" Sharp, where the NC stands for "Nobody Cares" but, true to [...]Continue Reading —›
Back on June 25th, at the 2010 NHL Entry Draft, the Canucks traded away Michael Grabner, Steve Bernier, and their 1st round pick to the Florida Panthers for defenseman Keith Ballard and forward Victor Oreskovich. The Panthers turned that first round pick into Quinton Howden, waived Grabner out of training camp, then waived Bernier recently [...]Continue Reading —›


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Many national, state and local bar associations and other legal organizations afford students the opportunity to compete for a variety of fellowships and scholarships and in numerous legal writing competitions.
Fellowship programs are often associated with law-related internships that provide students with exceptional practical legal training and important networking opportunities.
Scholarship programs, while helping to defray the cost of law school attendance, offer additional benefits — the prestige of being the only student or one of a small number of students to be selected for the scholarship as well as opportunities to network with the attorneys who are awarding the scholarship.
Essay-writing competitions enable students to hone their legal research, writing and advocacy skills; produce a writing sample for prospective employers; and, possibly, have a published work that can be promoted on a resume.
Be sure to check PSLawNet, the online source for information on public interest careers and opportunities. The site has information and resources on postgraduate fellowships in a variety of practice areas and employers, including those in government, public interest organizations and educational institutions. Their database includes moe than 300 fellowship listings and an application deadline calendar.


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The delayed and much-anticipated Marc Jacobs show closed out New York Fashion Week last night, delivering this final word: pajamas rule. Jacobs was seduced by the bedroom for F/W 2013, filling out his collection with boyish pajama tops, piped pants and high-waisted briefs. The famed designer even took his bow on the catwalk in a debonair foulard number – paired with sneakers, of course. Step aside, Julian Schnabel.
Ooh Mama, More Pajamas!
I love Pyjamas, especially the designs that are emerging now, keep them coming!


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About Jain Samaj
Jain Samaj Directory
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Shree Rishabh Dev Ji
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Shree Chandraprabhu Ji
Shree Pushpadanta Ji
Shree Sheetalnath Ji
Shree Shreyansnath Ji
Shree Vasupujya Ji
Shree Vimalnath Ji
Shree Anantnath Ji
Shree Dharmanath Ji
Shree Shantinath Ji
Shree Kunthunath Ji
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Shree Mallinath Ji
Shree Munisuvrata Ji
Shree Naminath Ji
Shree Neminath Ji
Shree Parshvanath Ji
Shree Mahaveera Ji
Welcome to Jain Samaj India
The values of Jain religion are based on five vows viz.- non-violence, devotion to truth, non-stealing, celibacy and non-possession. The entire life style of the Jain Shravak and the Jain Sadhu emanates from these vows and the foremost is non-violence.
Bhagwan Mahavir said,
"If you kill someone, it is yourself you kill. If you overpower someone, it is yourself you overpower. If you torment some one, it is yourself you torment. If you harm someone, it is yourself you harm."
A wise man knows this and so he does not kill, nor does he overpower or torment anyone.
read more...
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Copyright © 2011-2012 All rights reserved.
Designed & Developed By: Daksh InfoSoft


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For many years, the All-Sports Booster Club has been committed to providing financial aid for all Shawnee Mission East athletic teams and cheerleading by purchasing a wide-variety of equipment. Additionally, the Booster Club helps finance the training and medical coverage for the athletic department. Please help support our many athletic programs by joining the All-Sports Booster Club. As a member, you receive two passes to all East home sporting events.
Advertising options and opportunities coming soon.


text: Info Search results 41 items matching your search terms. Filter the results. Item type Select All/None Page Event File Folder Image Link News Item Collection New items since Yesterday Last week Last month Ever Sort by relevance · date (newest first) · alphabetically Arrested Accusations: Reporting Abortions in Peru, 1890s-1940s Talk by Raul Necochea, Social Science and Humanities Research Council of Canada Postdoctoral Fellow, School of Public Health, University of Toronto Bio-Ancestry and Social Construction of Racial Identity in the Contemporary United States Minority health: Cultural resources and thriving despite lower status Presented by Cleopatra Abdou, PhD, RWJ Health and Society Scholar, University of Michigan Located in Events / 2011 Moral Economies of Medicine, talk: "Gynecological Intervention and Ecuador's Economy of Corporeal Care" "Scars of Nation: Gynecological Intervention and Ecuador's Economy of Corporeal Care," Elizabeth Roberts, PhD Located in Events / 2011 Preventive Medicine Seminar Located in Events / 2011 The First Antidepressant: Amphetamine and the Reinvention of Depression, 1930s - 1950s Presented by Nicolas Rasmussen, MPhil, PhD, MPH, School of History and Philosophy, University of New South Wales Located in Events / 2011 The Historical Context of the Autism Epidemic - Talk The Historical Context of the Autism Epidemic Located in Events / 2011 The HIV Poverty Thesis Re-Examined: Poverty or Inequality as an Underlying Cause of HIV in Sub-Saharan Africa? Presented by Ashley Fox, PhD, Department of Global Health and Population, Harvard Located in Events / 2011 Transplant Education Conference Series (TECS) Seminar: Record-setting Spanish Organ Procurement Model Special Transplant Education Conference Series (TECS) Seminar: "The Record-setting Spanish Organ Procurement Model: Success Factors and Ethical Challenges" Located in Events / 2011 A Colloquium on the Origin of Human Rights with Talal Asad Talal Asad, distinguished professor of anthropology at the CUNY Graduate Center, will participate in a colloquium on the origins of human rights. If you will attend, please read through the three papers linked to in this event entry prior to the colloquium. Next 10 items » [1] 2 3 4 5


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In past summers, Rodney, the fictional Ocean City lifeguard in the resort town's advertising campaign, has ventured to rescue New Yorkers and New Jerseyites from summer boredom.
After Hurricane Sandy, Rodney may have less convincing to do.
While Sandy affected a large swath of the East Coast, it made landfall on the Jersey shore and caused nearly $37 billion in damage to that state, according to recent estimates. In the beach town of Seaside Heights, a roller coaster knocked into the Atlantic Ocean has become a symbol of the destruction wrought by the storm.


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Dia's Gluten Free & Vegan Pumpkin GnocchiPosted by ♦***Admin--Dia***♦ on October 21st, 2009. Filed under: Casein Free, Dairy Free and Vegan, Vegetarian, Wheat and Gluten Free.
I'm very sorry for the almost 2 month long delay in posting a new recipe. I have been really broken hearted over a dear friend of mine passing away, and could barely eat, let alone cook. I hope you can understand.
Last night I was thinking of possible dishes for an all vegan Thanksgiving, and then suddenly remembered Halloween was coming up. I miss Halloween, it isn't something wonderfully celebrated here in the UK…Every year as a kid, my brothers and I weren't allowed to go trick or treating–Instead we went to our church's "Harvest Party". OK, sometimes after the Harvest Party my brothers and I would sneak out to go trick or treating, but no one had any candy left. Sigh. At these HPs we would be given a very small bag of candy, but only after we had spent the night playing sports and praying! Wait. Why do I miss Halloween so much? I guess I just miss the season. I love it when the leaves start changing colors, and well Halloween is really the kick off to the holiday season. I loved going for hay rides, visiting pumpkin patches, smelling the Shoo Fly Pie's in Lancaster, Pennsylvania and most of all spending time with my family and friends.
Anywayyyy, this Pumpkin Gnocchi can be a great treat for your kids before they venture out for candy (or Harvest Partying), or would make a great meal for two adults while waiting for the kids to come home.
It is simple to make, the only real time is spent waiting for the pumpkin to roast.
For the Pumpkin Gnocchi
1 small pumpkin (make sure it's edible…I could tell you stories!!!)
1 sweet potato
1 cup of rice flour (or more as you need it)
For the Sauce
2 tsp cinnamon
2 tsp ginger
2 tablespoons of vegan spread
a sprinkle of unrefined brown sugar* (optional)
Preheat oven to 180°C (356°F)
Peel the pumpkin and chop into chunks.
Place chunks in casserole dish and heat in the oven for 45 minutes or until soft.
At some point while the pumpkin is roasting, heat the sweet potato up in the microwave. It should take about 8 minutes in an 850 w Microwave.
When the sweet potato is done, slice it open and spoon out the insides into a mixing bowl.
Add the roasted pumpkin to the sweet potato and either mash with a potato masher or pour into a food processor. Blend well.
Mix the now pumpkin/sweet potato puree with the 1 cup of rice flour, until it forms a nice dough.
Break the dough into 4 sections. Roll each section into a sort of long sausage.
Slice each of the 4 sausages into gnocchi size pieces.
Next take a fork and press it on top of each piece to give it that pretty gnocchi style.
Bring a pot of water to a boil, and place all gnocchi pieces inside for 3-4 minutes. They will float up to the top when done.
Meanwhile pan fry the sauce which is quick and easy:
take the vegan spread, cinnamon, ginger and optional brown sugar and heat for about 2 minutes or until melted.
Drain gnocchi and pour the cinnamon and ginger sauce on top.


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The House of the Raging Bull has shown the first driveable prototype of the Lamborghini 'Concept S' at the Monterey Concorso Italiano and at the Pebble Beach Concours d'Elegance in the USA.
The Lamborghini 'Concept S' design study premiered at this year's Geneva Motorshow as an extreme and spectacular expression of the Lamborghini brand. It was created at the Centro Stile Lamborghini in Sant'Agata Bolognese by Luc Donckerwolke, who drew inspiration from the classic single-seater racing cars of the past.
The astonishing amount of public interest at the Geneva Motor Show prompted the decision to build a driveable prototype in order to further gauge potential customer demand.
"The 'Concept S' represents everything that Lamborghini stands for. It is extreme, uncompromising and Italian," commented Stephan Winkelmann, President and CEO of Automobili Lamborghini. "A production decision has not yet been made, though we were encouraged by the positive response to the driveable prototype at both Monterey and Pebble Beach."
The driveable 'Concept S' prototype has only changed slightly compared to the original design study. For example, the so-called 'saute-vent' windscreens were re-designed for homologation reasons. The look of the car results even more extreme than the original.
Classic single-seaters did not have a traditional windscreen, but utilised the 'saute-vent' in order to direct air over the head of the driver. In the 'Concept S', these devices divide the cabin into two distinct compartments, giving the car an aggressive and futuristic look.
They also create a space between them that acts as an additional air inlet for the engine, which is positioned behind the seats. And like the Gallardo, which serves as the basis for this stunning supersportscar, the 'Concept S' is equipped with a powerful V10 engine.
The aerodynamics of the 'Concept S' have been optimised thanks to front and rear spoilers and a large rear diffuser. An electronically controlled, retractable central rear view mirror allows the driver to see what is happening behind the car - when required !
A concept design by Slavche Tanevski at the design faculty of the Munich University of Applied Sciences
(added on January 31. 2010)
A new concept based on the sensual looking Lamborghini Miura from the Sixties.
(added on January 5. 2006)
Several concepts and ideas have surfaced for a Jalpa successor, this is yet another one.
(added on October 24. 2000)
Lamborghini SUV Concept confirmed
Apparently someone at Audi has confirmed the speculations about a Lamborghini SUV
(added on February 2. 2012)
Huracan LP610-4 Spyder and LP650-5 Superleggera rendered
With the basic Lamborghini Huracan LP610-4 being unveiled I went to work on creating a Spyder concept, a Superleggera edition and the Super Trofeo race model.
(added on December 22. 2013)
August 25. 2005
Text © Automobili Lamborghini SpA
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Chris Kelly's Mentor Jermaine Dupri: I Wish I Could Have Saved Him
Those close to Kris Kross rapper Chris Kelly, who passed away this week at age 34, are wishing they could have done more to help him.
Famed music producer Jermaine Dupri, who helped discover Kris Kross, wishes he had known about Chris's alleged drug issues, according to Us Weekly.
"If I would have known, I would have tried to put my foot forward to help the situation," Jermaine says.
"I'm hearing about this just like everybody else and I'm not really too believing of all of it, but at the same time, I can't say that I didn't know," he says. "I wasn't there to know about it, and I hate it because I feel like if there were people around and knew about it, then they should have waved the flag."
Police reports have revealed that Chris apparently used cocaine and heroin on the night before his death.
Jermaine founded So So Def Records and was only 18 when he discovered Kris Kross.
"He was just a natural kid, like a person that you want to be around at all times because he would never not want to be doing anything," Jermaine adds.
Other celebs are remembering their time with Chris, including TLC member Rozonda "Chilli" Thomas.
"I used to hang out at his house with his mom and pick him up," she says. "He was like a teenager and just the sweetest thing, just a regular cool teenage boy, so we were really close and then the last time I saw him was last year at a concert."
Our thoughts go out to anyone who was close to Chris.
Source: Us Weekly


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Asus F6A
SpecificationsNotebook: Asus F6A (F6 Series)
Processor: Intel Core 2 Duo P8400
Graphics Adapter: Intel Graphics Media Accelerator (GMA) 4500MHD
Display: 13.3 inch, 16:10, 1280x800 pixels, glossy: yes
Weight: 1.9kg
Price: 900 euro
Average of 1 scores (from 1 reviews)
Reviews for the Asus F6A
Source: PC Praxis - 4/09
Comparison, , Length Unknown, Date: 03/01/2009
Rating: Total score: 87% price: 70%
Intel Graphics Media Accelerator (GMA) 4500MHD: Onboard (shared Memory) GPU built in the GM45, GE45 and GS45 chipset (Montevina). Because of two more shaders and a higher core clock, much faster than the old GMA X3100. Still not advisable for gamers (DirectX 10 games not playable or only with very low settings). The integrated video processor is able to help decode HD videos (AVC/VC-2/MPEG2) , e.g., for a fluent Blu-Ray playback with slow CPUs.
Only some 3D games with very low demands are playable with these cards.
» Further information can be found in our Comparison of Mobile Graphics Cards and the corresponding Benchmark List.
Intel Core 2 Duo: This is the Core Duo and Core Solo successor with a longer pipeline and 5-20% more speed without more power consumption. As an addition to the Core Duo design there exists a fourth decoder, an amplified SSE-unit and an additional arithmetical logical unit (ALU).
The Core 2 Duo for laptops is identical to the desktop Core 2 Duo processors but the notebook-processors work with lower voltages (0.95 to 1188 Volt) and a lower Frontside bus clock (1066 vs 667 MHz). The performance of equally clocked notebooks is 20-25% lower than Desktop PCs because of the lower Frontside bus clock and the slower hard disks.
Middle class dual core CPU with a TDP of 25 Watt. For high end gamer the performance could be not sufficient (for class 1 graphic cards).» Further information can be found in our Comparison of Mobile Processsors.
13.3": This is a common display format for subnotebooks. Netbooks, UMPC and some subnotebooks have tinier displays. Nevertheless, the majority of standard laptops has a higher format. The advantage of a small display is, that the subnotebook can be small dimensioned and can be carried easily. Further the small display needs few energy, which improves the battery runtime and in consequence the mobility. The disadvantage is that the reading of texts is a bit exhausting for the eyes, especially with high resolutions.» To find out how fine a display is, see our DPI List.
1.9 kg: These sub-notebooks weight less than the average of all notebooks, but represent a heavier class of weight among the sub-notebooks. 12 inch displays are normal for this class of weight.
Asus: ASUSTeK Computer Incorporated, a Taiwanese multinational company, produces motherboards, graphics cards, optical drives, PDAs, computer monitors, notebook computers, servers, networking products, mobile phones, computer cases, computer components, and computer cooling systems. The company's 2007 revenues reached US$6.9 billion. ASUS also produces components for other manufacturers. The Eee PC initiated the netbook boom in 2008.
87%: This is a good rating above average. Nevertheless you should not forget, that 10-15% of all notebook-models get a better rating.
» Further information can be found in our Notebook Purchase Guide.


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I have not been around much for a couple of years but I have been lurking every now and then. I kind of got in a depressive funk after losing my parents and starting my own business but the kids have kept me sane and helped me to fight my way out of the depressive hole I was in.
Ok enough of that lets get to the really good news, some of you may remember from when I was on here a lot that my daughter Karissa is a Wrestler and has been since she was 5 well she is now almost 18 and a Senior in HS. Karissa is still Wrestling and has a few Colleges recruiting her.
1. OCU - no offer but they want her
2. Missouri baptist - has offered 1/2 a ride, visiting there Monday the 20th
3. Waldorf - wants her to wrestle and play goalie for there soccer team, going to put together a dual scholarship package. Going to visit March 12th
4. King - no offer yet just called saying they would like her to wrestle for them.
5. Jamestown - no offer yet just called saying they would like her to wrestle for them.
6. Lindinwood - Coach Toccara Montgomery wants Karissa to visit also.
I think she will probably pick Waldorf but Mobap may pull it out, OCU is loaded but doe's not have the scholarship money available to match Waldorf or Mobap.
We will make some visits and she will work out with a few of the teams and I guess we will just wait to see were she feels most comfortable.
Yes I am 1 proud Father!


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While visiting Uganda last week I met with people who took part in the Walk to Work activities last year in April.
Read the Al Jazeera coverage of the Walk to Work here.
Last year I followed the Walk to Work via social media, and hence it was a pleasure to see how the concept of Walk to Work has seeped through into ie. several pieces of art in a gallery, this one titled: 'Sometimes I walk to work', and DVDs with recordings from the actual walks, clashes with police etc. - now placed next to other bestsellers.


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This is one of the best hotel i have stayed in in awhile. The rooms where a nice size, the service was great, and the price was great.
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The rivalry resumes Monday night at Eggleton Field.
A year ago, the Lancaster junior Legion team finished second to Gaffney in the regular-season league race with both holding the same record, but Gaffney won on head-to-head meetings. In the state tournament, P-31 earned some revenge, eliminating Gaffney from the postseason tourney.
Now the two clubs are prepared to meet again in an early showdown in Legion baseball League V junior play.
The Lancaster chapter of the S.C. Junior Golf Association launches its 14th season Monday with its 2009 opener at White Plains Golf Club in Pageland.
The White Plains tournament is the first of six chapter tournaments to be played this season.
"We're real pleased with the response we've had for the junior golf association," said Lancaster chapter director Raymon Chisom.
The Lancaster American Legion Post 31 junior baseball team capped a perfect week with an 8-5 win at Eggleton Field on Thursday night.
P-31, playing its fourth game in as many days, started strong with a four-run first inning and kept the upper hand for the victory.
"We had a great week overall," said Lancaster P-31 junior team coach Josh Pauling. "I am very proud of these boys this week. To win four games in one week is a difficult task at any level, and hats off to these young men for this accomplishment."
Some employees are losing their jobs due to funding cuts in the Lancaster County School District's new budget.
The school board adopted the $65.9 million budget for 2009-10 on Tuesday night. The vote was 5-0.
Board members Peter Barry and Bobby Parker were absent.
The budget calls for the elimination of nearly 38 positions, 25.5 of which are teaching posts.
An assistant principal, two instructional specialists and six counselors will also be cut, said district finance director Tony Walker.
GREAT FALLS - Sunlight sparkling on the flowing waters of Rocky Creek, birds singing in the stately hardwoods and the sound of water splashing over rocks are just a few of the pleasures that visitors will experience along the Rocky Creek Trail.
The Great Falls Home Town Association and the town of Great Falls invite the public to celebrate the opening of the Rocky Creek Trail on Thursday.
The 3-mile trail, funded through a grant from the S.C. Department of Parks, Recreation and Tourism department, represents a small step towards the future Carolina Thread Trail.
A Lancaster man was shot in the buttocks at a local nightclub early Sunday.
According to a Lancaster County Sheriff's Office incident report, deputies responded to Grown Folks on Kershaw Camden Highway about 3:30 a.m. because of a shooting. When deputies arrived, they found the 25-year-old victim on his stomach near the road. The man told deputies that he had been shot by an unknown assailant in a black vehicle.
The role of animals in Native American culture will be the focus of a day-long event this weekend at the University of South Carolina at Lancaster.
Honoring the Animals Day begins at 9 p.m. Saturday and will be held at the Bradley Arts and Sciences Building.
The event will explore the relationship between animals and Native Americans, and the role of certain animals, particularly in Catawba and Cherokee Indian culture.
The event is free and open to the public.
Gathering on the front porch of the Springs House in downtown Lancaster, representatives from several local charitable organizations hoped to get the word out about a new county food initiative.
The heads of the Springs Close Foundation, HOPE (Helping Other People Effectively) in Lancaster, KARE (Kershaw Area Resource Exchange), Christian Services and the Lancaster County Council on Aging were on hand Thursday to discuss their collaborative efforts to eliminate hunger in the county.
No matter what your lifestyle, incorporating fitness into your daily schedule is easier and more natural than yothink. Here are a few suggestions that can help make yofit fitness into your daily routine. However, ask your doctor before engaging in strenuous physical activity
At work
Walk, bike or jog to work once a week.
Past generations turned to low-cost frozen dinners when the money got tight. These days, cutting back means skipping restaurants and cooking at home instead, according to Sloan Trends, which follows changes in eating habits.
According to a recent report in Food Technology, 53 percent of consumers are cooking from scratch more frequently.
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The Lancaster News is your source for local news, sports, events, and information in Lancaster County and Lancaster, South Carolina, and the surrounding area..


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As the Spanish forward moves from Liverpool to Chelsea for a British record of £50 million, we take a whimsical look at what the Blues might otherwise have spent their readies on.
- 2.1 million adult entries into the London Dungeon — equivalent to the population of Vancouver, Kosovo or the Canary Islands. Although maybe they could negotiate a group discount.
- 1000 clean-ups after student protests
- 347.4 more years of Boris Johnson at his current salary
- 31.25 new Routemasters
- 29 years of service from commentator Andy Gray on his former Sky salary
- 28 years of New Year's fireworks
- 2.6 AcelorMittal Orbits
- 2 cross-river cable cars
- 1 Damien Hirst crystal skull
- 1 royal wedding
And, of course, the lion's share of funding cuts to any of London's local councils.
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Make quick work of dispensing tickets, order pickup and route accounting with the CipherLab 8000 Series pocket-size computer. Scan and batch upload in fast, easy steps to speed product ordering and inventory management. Streamline many operations, like shelf labeling. The 8000 Series is small and light enough to keep with you all day long, inconspicuously tucked out of the way in a pocket, yet ready to go to work in an instant.


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Like most galaxies, the Milky Way has a supermassive black hole in its center. For the most part, however, that black hole is dormant – meaning that it isn't emitting large amounts of radiation. That's because that radition, in the form of X-rays, gamma rays, radio waves, is emitted when large objects – like giant gas clouds or stars – are brought into the black hole's gravitational field. Matter falling into the black hole is subjected to exceedingly large gravitational forces, and the result is a blaze of light and radiation that is very visible to telescopes.
However, a team of scientists has uncovered evidence that approximately two million years ago – when humanity's earliest ancestors newly stepped on the world – the supermassive black hole in the center of our galaxy, Sagittarius A*, erupted in an explosion of high-energy radiation called a "Seyfert flare." During that time, the radiation from the black hole was about 100 million times more powerful than it is today. Our ancestors may have even seen the huge burst of light themselves, but this was hundreds of thousands of years before any kind of human was taking notes.
Astronomers have seen signs that there was such a Seyfert flare for the past few years, in the form of antimatter radiation and other clues. However, this new research enables astronomers to closely date when that explosion could have happened.
The key the astronomers found was actually discovered 20 years old, in the form of a strange glow that astronomers had noticed in the Magellanic Stream. The Magellanic Stream is composed of large clouds of gas – mostly hydrogen – that stretch for light years in the wake of the Milky Way's two companion Galaxies, the Large and Small Magellanic Clouds. The Stream is about 2 billion years old.
"We didn't understand the cause. Then suddenly we realised it must be the mark, the fossil record, of a huge outburst of energy from the centre of our Galaxy," remarked researcher Joss Bland-Hawthorn in a press release.
As the radiation traveled from the explosion at the heart of our galaxy, it eventually hit the Magellanic Stream, where the high energy hitting the gas clouds caused them to light up, the same way cosmic radiation causes auroras here on Earth.
Having arrived at that thought, the astronomers then crunched the numbers, using complicated geometries to figure out the direction of a potential eruption. Then they determined how long it would take the radiation to get to the Magellanic Stream, then how long it would take for the light from that explosion to then be visible here on Earth. Based on those calculations, the eruption most likely occurred about 2 million years ago.
The team also considered a number of other alternative sources for the glow, and found that they were far less likely due to the amount of energies involved. Additionally, these findings are consistent with the other signs of an eruption of Sagittarius A* that have been discovered in recent years.
"All this points to a huge explosion at the centre of our Galaxy," said researcher Philip Maloney.
Basically, the glow in the Magellanic Stream is like a fossil record of the black hole's explosion. Think of it as the cosmic equivalent of the iridium anamoly – a large concentration of iridium in the Earth's crust dating back 65 million years, which is most likely the sign of the huge asteroid impact that finished off the dinosaurs.
Although this is a big step to understanding the behavior of supermassive black holes, there's still a lot of work to do. For one, as the researchers note in their paper, "[w]e cannot yet identify the specific event which triggered the burst of Seyfert activity." Solving the riddle of why Sagittarius A* erupted may provide clues as to why these sporadic events occur, and hint to the next time that it will erupt.
But unlike two million years ago, the glorious images of the next eruption will be preserved for our descendants to marvel at.


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Easton wrestled as a sort-of underdog last season, emerging from the No. 4 seed to win the district duals wrestling title. Returning to the role of favorite suited the Red Rovers fine Saturday.
With two sure-fire performances in the semifinals and final, Easton defended its District 11 Class 3A duals title and established itself as the probable favorite for this week's state tournament. After overwhelming Northampton 47-12 in the semis, the Red Rovers defeated Nazareth 33-22 for their 10th overall title in the district duals.
"It's easier, and maybe more fun, to do the chasing than to be the guy with the target on your back, But I thought the kids handled it very well."
Coach Steve Powell, Easton
The Red Rovers (19-1) advanced to next week's PIAA duals for the 10th time since 2000. They will face the winner of the Spring-Ford/Big Spring pigtail match in Thursday's quarterfinal round at the Giant Center in Hershey.
Nazareth (12-4) will wrestle Owen J. Roberts, the third-place team from District One, in a pigtail bout at 7 p.m. Monday at Methacton High. The winner advances to Hershey, where it will wrestle the District 7 champ in the first round.
Easton and Nazareth are on opposite sides of the bracket, meaning a third meeting is possible in Saturday's state final.
For Complete story by: Rob Kandell, The Morning Call
Match Results:
285 – Jalal Paige (Easton) def. Aaron Bradley (Nazareth) – Decision 5-2
103 – Kyle Baker (Easton) def. Tyler Tarsi (Nazareth) – Technical Fall 15-0 @ 4:26
112 – Chase Zemenak (Nazareth) def. Peter Stanley (Easton) – Decision 3-2
119 – Evan Disora (Easton) def. Adam Delgado (Nazareth) – Decision 10-7
125 – Franco Ferraina (Nazareth) def. Robbie Rizzolino (Easton) – Decision 3-1
130 – Zachary Horan (Nazareth) def. Calvin Daly (Easton) – Major Decision 12-3
135 – Gregory Noll (Nazareth) def. Mark Misczenski (Easton) – Decision 6-0
140 – Joey Rizzolino (Easton) def. Ian Stout (Nazareth) – Major Decision 10-2
145 – Anthony Minotti (Easton) def. Hunter Weidner (Nazareth) – Pin 0:32
152 – Mitchell Minotti (Easton) def. Wyatt Miller (Nazareth) – Pin 2:54
160 – Ryan Krecker (Nazareth) def. Solomon Sohn (Easton) – Pin 3:45
171 – Mason McIntyre (Easton) def. Eric Wolak (Nazareth) – Decision 7-6
189 – Ben Bradley (Nazareth) def. Zack Bambary (Easton) – Decision 3-1
215 – Tyler Greene (Easton) def. David Wilke (Nazareth) – Decision 5-2


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Gregg Allman''s first solo album in 14 years was produced by T Bone Burnett and features 11 covers of songs from legendary bluesmen Muddy Waters, Otis Rush, B.B. King, Bobby Bland, Sleepy John Estes, and many more, PLUS an original song written by Gregg and the Allman Brothers'' Warren Haynes called "Just Another Rider." Gregg''s backing band on the album includes Dr. John on piano, Doyle Bramhall II on guitar, and the incomparable rhythm section of bassist Dennis Crouch and drummer Jay Bellerose (from Robert Plant and Alison Krauss''s multiple Grammy-winning `Raising Sand'' album).
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