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US 6683397 B2 Abstract An electric machine includes a stator and a permanent magnet flux-concentrating rotor. The permanent magnet flux-concentrating rotor has permanent magnets and pole pieces. The permanent magnets are engaged between the pole pieces. The electric machine also has at least one magnetic-field detector that is mounted on the stator. The at least one-magnetic-field detector is mounted on the stator in such a manner as to detect a magnetic field of the permanent magnets in a location that overlaps a peripheral region of the rotor when the machine if observed on the axis of rotation of the rotor.
Claims(13) 1. An electric machine, comprising:
a stator;
a permanent magnet flux-concentrating rotor having permanent magnets and non-magnet pole pieces, the permanent magnets being engaged between pole pieces; and
at least one magnetic-field detector mounted on the stator in such a manner as to detect a magnetic field of the permanent magnets in a location that overlaps a peripheral region of the rotor when the machine is observed along a direction that is parallel to the axis of rotation of said rotor.
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Description The present invention relates to rotary electric machines and more particularly, but not exclusively, to synchronous electric motors having permanent magnets. In machines having permanent magnets, it is known to use magnetic field detectors in order to know the position of the rotor and to control the excitation of the stator in suitable manner. Known detectors include a Hall effect sensor that is capable of detecting the magnetic field resulting from magnets added to the rotor and therefore distinct from the magnets serving to generate the driving or electromotive force. The invention may enable to make it easier to build electric machines having permanent magnets. According to one aspect, the invention provides an electric machine comprising a stator and a permanent magnet flux-concentrating rotor. The rotor may have permanent magnets being engaged between pole pieces. The machine may have at least one magnetic-field detector mounted on the stator in such a manner as to detect the magnetic field of the magnets of the rotor in a location that overlaps a peripheral region of the rotor when the machine is observed on the axis of rotation of the rotor. Thus, in the invention, it is the magnetic field of the magnets for interacting with the stator that may be detected, such that it may not be necessary to add to the rotor magnets that are intended merely to enable the angular orientation of the rotor to be known. This therefore may simplify manufacture of the rotor. When the power supply to the motor is polyphase electricity having n phases, the motor preferably includes n detectors fixed on n teeth of the stator, which teeth are advantageously consecutive teeth, thereby facilitating installation of the detectors, access to the detectors, and removal of the electrical conductors connected to the detectors, since all the detectors can be grouped together facing an opening in the case of the motor. In a particular embodiment, the detectors are fixed on one axial end of the magnetic circuit of the stator and each extends along the axis of a tooth. In a particular embodiment, each detector includes a Hall effect sensor. Still in a preferred embodiment, each tooth receives an individual coil which co-operates with the tooth to leave a gap which receives the detector or electrical conductors connected to the detector. Each individual coil advantageously comprises a bundle of insulated wires, the bundle being substantially flat and wound around a winding axis in such a manner as to form a plurality of superposed turns, the cross-section of the bundle in the superposed turns having a long dimension that extends substantially perpendicularly to the winding axis of the coil. The wires are preferably circular in section, having a diameter that lies in the range 0.3 millimeters (mm) to 2.5 mm, for example. This configuration makes it possible to reduce high frequency losses within the copper at high speeds of rotation of the rotor. The invention applies more particularly to a motor having a flux-concentrating rotor, the permanent magnets being engaged between pole pieces, the rotor including at least one cheek-plate made of a non-magnetic material, the outside radial edge of the cheek-plate extending slightly set-back from the outside radial edges of the magnets and of the pole pieces in such a manner as to provide an annular region in which the magnetic field can be detected by the above-mentioned detector(s). Advantageously, the stator has windings on teeth. In a stator with windings on teeth, each tooth serves as the core of a winding. In addition, the number of teeth nteeth is advantageously a function of the number of pairs of poles npairs and the number of phases nphases in compliance with the relationship nteeth=npairs*nphases. The combination of a flux-concentrating rotor and a stator with windings on teeth makes it possible to have a machine that is powerful in a small volume, thus making it possible in particular to mount the motor in a cantilevered-out position at the end of a shaft, thereby reducing the number of bearings. The number of teeth and of coils is relatively small, thereby contributing to reducing the cost of the machine. In addition to a magnetic field sensor, each detector can also include a temperature sensor and the location of the temperature sensor between the coil and the tooth serves to give a good image of the real temperature of the electrical circuit of the corresponding phase. Other characteristics and advantages of the present invention will appear on reading the following detailed description of non-limiting embodiments of the invention, and on examining the accompanying drawings, which drawings form an integral portion of the description, and in which: FIG. 1 is a diagrammatic perspective view of a synchronous motor constituting an embodiment of the invention; FIG. 2 is a diagrammatic plan view looking along arrow II of FIG. 1; FIG. 3 is a diagrammatic axial section of the motor on III�III of FIG. 2; FIG. 4 is an enlarged view of a detail IV of FIG. 2; FIG. 5 shows the stator in isolation, in perspective, and in diagrammatic manner; FIG. 6 shows a sector of the magnetic circuit of the stator in isolation and in perspective; FIG. 7 shows how the FIG. 6 sector is assembled with an identical sector; FIG. 8 shows an individual coil in isolation and in perspective; FIG. 9 is a section on IX�IX of FIG. 8; FIG. 10 is a diagram showing a set of coils used for making the stator; FIG. 11 is a diagram showing how sets of coils are put into place on the stator during manufacture thereof; FIG. 12 is a view analogous to FIG. 11, in highly diagrammatic and simplified form once all of the sets of coils have been put into place, to show the circular paths followed by the current-feed cables; FIG. 13 is a diagrammatic front view of the rotor; FIG. 14 is an end view of the rotor shaft shown in isolation; FIG. 15 is a diagrammatic axial section on XV�XV of FIG. 14; FIG. 16 is a plan view of a pole piece of the rotor shown in isolation; FIG. 17 shows how pole pieces are assembled on the rotor shaft; FIG. 18 is a diagrammatic cross-section of the rotor shaft after the magnets and the pole pieces have been put into place; and FIG. 19 is a diagram showing one way in which the coils can be electrically interconnected (coils numbered 1 to 12). FIGS. 1 to 4 show a synchronous motor 10 of the invention comprising a stator 100 and a rotor 200. The motor 10 is brushless, it has a flux-concentrating rotor, and its stator has windings on teeth, and it operates on three-phase AC. The stator 100 has a steel case 110 with a lateral opening 111 in particular for passing electrical conductors for powering the stator windings. On the outside, the case is provided with fixing tabs 112 and with a hook 113 for hoisting purposes. In the example shown, the stator 100 has a magnetic circuit that comprises a plurality of identical sectors 120, one of which is shown in isolation, in perspective in FIG. 6. Each sector 120 is constituted by a stack of identical magnetic laminations that are superposed and clipped together so as to constitute a unitary assembly, with clipping being obtained using a conventional technique whereby each lamination is subjected to spot deformation at a plurality of assembly points 121. Using a stack of magnetic laminations serves to limit losses due to induced currents. In a variant, the magnetic circuit of the stator could be formed by superposing laminations, each of generally annular shape, and then cutting out all of the teeth 130 of the stator therefrom. In another variant, each of the sectors could include a plurality of teeth. When assembled together, two adjacent sectors 120 form a tooth 130, which tooth is used for receiving an individual coil 340, as can be seen in FIG. 5 in particular. The number of teeth nteeth in the example described is twelve, and the motor is designed to be powered with three-phase AC and the rotor has 8 poles. Naturally, the number of rotor poles could be different and in particular it could be equal to 12 or 16, for example. Although presenting certain drawbacks as mentioned above, the stator could also have a number of stator teeth that is not associated with the number of rotor pole pairs npairs and the number of phases nphases by the relationship nteeth=npairs*nphases. On its sides 123 a and 123 b for co-operating with adjacent sectors 120, each sector 120 has respective portions in relief 124 a and 124 b. These portions in relief 124 a and 124 b are complementary in shape having a profile that is generally triangular when seen from above, one being recessed and the other projecting, and having two sides that are substantially rectilinear and interconnected by a rounded portion. Co-operation between the portions in relief 124 a and 124 b contributes to positioning the sectors 120 properly relative to one another while assembling the magnetic circuit of the stator. Each sector 120 also has respective grooves 125 a and 125 b in its sides 123 a and 123 b, each groove being of semicircular cross-section and situated in the vicinity of the portions in relief 124 a and 124 b so that two adjacent grooves together form a hole 125 of circular section when the sectors 120 are assembled together. These holes 125 serve for receiving three detectors 190 as described in greater detail below. In FIG. 7, it will be observed that the air-gap E at the interface between two adjacent sectors 120 occupies the middle of the corresponding tooth 130, thereby enabling magnetic losses to be reduced while the machine is in operation since magnetic flux can flow from one-half tooth to the adjacent half-tooth within the same sector 120 without encountering an air-gap. In addition, the sectors can be made with elements that are cut out practically without scrap using cutting tools of relatively small size, i.e. tools capable of high rates of throughput. The sectors 120 are forced as a whole into the cylindrical case 110, and the magnetic circuit formed by the sectors 120 is held together by the radial compression forces exerted by the case 110 on the sectors 120, with the bearing surfaces between sectors being relatively large. Each sector 120 defines a slot 140 whose opposite sides 141 a and 141 b are at an angle i of more than 90� relative to the adjacent regions 142 a and 142 b of the bottom of the slot 140, which regions are themselves perpendicular to radii passing through the line where the corresponding tooth meets the bottom of the slot. In the embodiment shown, the angle i is 90.4�, but this value is merely an example. Each of the sides 123 a and 123 b of the sectors is generally in alignment with a radius, ignoring the portions in relief 124 a, 124 b, 125 a, and 125 b, and the width of each tooth 130 increases slightly on going away from the rotor (ignoring the cutouts 144 a or 144 b formed close to its free end 131 facing the rotor). It will be observed on examining FIG. 7 that in the vicinity of its free end 131 each tooth 130 does not have pole swellings, in contrast to many known stators which present slots that are semi-closed. In the example shown, the end portions 132 a and 132 b of each tooth 130 situated between the free end 131 and the cutouts 144 a or 144 b are in alignment with the sides 141 a and 141 b respectively. The free end 131 is a circularly cylindrical portion on the same axis as the axis of rotation of the rotor, and it is concave towards the rotor. The bottom of each slot includes a middle region 142 c interconnecting the regions 142 a and 142 b and perpendicular to a radius intersecting the slot 140 at half-width, as represented by chain-dotted lines in FIG. 7. As mentioned above, each tooth 130 receives an individual coil 340 occupying substantially half of the volume of each of the slots 140 adjacent to the tooth 130 in question. FIG. 8 shows an individual coil 340 in isolation. This coil is formed by winding a bundle 341 of enameled electric wires 342 around a winding axis W, the bundle being substantially flat in cross-section, as can be seen in FIG. 9. When the bundle 341 is observed in cross-section through the turns, its long dimension extends substantially parallel to the winding axis W. In the example shown, the bundle 341 has ten individual conductors 342, each of circular section. The bundle 341 forms about twenty superposed turns 343. Within the turns, the conductors 342 are electrically insulated from one another by using wire that is enameled. The conductors 342 are stripped at their ends to form electrical connection ends 344 a and 344 b, each of which is curved towards the midplane of the coil perpendicular to the winding axis W so as to form a hook. At the end of the coil manufacturing process, each of these hooks is open towards the body of the coil. FIG. 8 shows that all of the conductors 342 at the end 344 a are curved upwards and then towards the body of the coil, while the end wires 344 b are curved downwards and then towards the body of the coil. The ends 344 a and 344 b do not project significantly beyond the planes of the two end faces of the coil. The turns constituting the coil body can be held in the superposed state by adhesive strips of cloth 345 prior to being impregnated in resin. Sleeves 346 of insulating sheath are engaged on the portions of the bundle 341 that extend between the ends 344 a, 344 b and the body of the coil. The inside section of the coil 340 is generally rectangular in shape, as can be seen in FIG. 10. The coils 340 are wound on formers having two opposite large faces that are plane, making between them the same angle as between the sides 141 a and 141 b of a tooth, such that the width of the inside section of each coil varies perceptibly from one end face to the opposite face. This can be perceived if any attempt is made to mount a coil the wrong way round on a tooth 130 of the stator 100. In FIG. 10, it can be seen that the coils 340 are electrically connected via one or other of the electrical connection ends 344 a or 344 b to partially-stripped sheathed electrical conductors 150 prior to being mounted on the teeth 130 of the stator 100. The hooks formed by the ends 344 a and 344 b are arranged, for example, in such a manner as to fit substantially around the outside diameter of the electrical conductors 150 in the stripped portions 151. These stripped portions can be formed not only at the ends of the electrical conductors 150 but also between them, by removing a limited length of insulating plastics material sheath. In the example described, sets of two coils 340 are made up and subsequently mounted on the corresponding teeth 130, as shown in FIG. 11. Sheets 349 of insulation are interposed between the teeth and the bottoms of the slots and the coils. The ends of these sheets 349 can be seen in FIGS. 5 and 11. As more and more coils 340 are mounted on the teeth 130, pieces of support shim 160 are slid into the cutouts 144 a, 144 b so as to close off the slots 140. As can be seen in FIG. 4, these pieces of shim 160 include partitions 161 extending between the portions of the two coils 340 that are received in the corresponding slot 140. Once all of the coils 340 are in position, the cables 150 extend along substantially circular paths on one side of the magnetic circuit of the stator, being set back from the free ends 131 of the teeth, as shown in FIG. 12, these cables being attached to one another by collars, and then the stator is impregnated with an insulating resin in conventional manner. The particular electrical interconnections between the twelve coils is shown in FIG. 20, but that is merely one example. It will be understood that it is particularly advantageous to use individual coils 340 installed on teeth of non-constant width in the manner described above, since that makes it much easier to replace coils 340. To replace a coil 340, once the rotor 200 has been removed, it suffices to unsolder the ends 344 a and 344 b of a coil from the corresponding stripped portions 151 and to remove the pieces of shim 160 concerned, whereupon the coil 340 can be extracted. A resin-impregnated replacement coil 340 can then be put into place by being engaged on the previously released tooth 130, after which its ends 344 a and 344 b can be soldered to the stripped portions 151. The convergence of the sides 141 a and 141 b of the tooth 130 towards the rotor and the corresponding shape of the inside section of the coil contribute to preventing the coil from moving on the tooth 130. A repair can be performed on site without it being necessary to return the machine to the manufacturer, and without it being necessary to re-impregnate the stator, thus making it possible to shorten repair time. The motor 10 can advantageously be shipped together with one or more replacement coils 340. The rotor 200 is described below with reference to FIGS. 13 to 18. The rotor comprises a non-magnetic shaft 210 shown in isolation in end view in FIG. 15, having a central portion 211 that is generally annular in shape, and at its periphery a plurality of splines 220 serving for securing pole pieces 230, each constituted by a stack of identical magnetic laminations that are superposed and clipped together. The use of superposed magnetic laminations serves to reduce losses due to induced currents. In cross-section, the splines 220 are generally T-shaped. The pole pieces 230 are not magnetically interconnected, since the shaft is made of a non-magnetic material. FIG. 17 shows a pole piece 230 in isolation as seen from above. Each pole piece 230 has a cutout 250 of a shape adapted to engage on a spline 220 by sliding parallel to the axis of rotation of the rotor. The splines 220 are formed integrally with the central portion 211, out of aluminum, by being machined in the present example, but other techniques such as drawing or injection could be used. It will be observed that the pole pieces 230 in the example described are not engaged on anything other than the splines on the shaft. The splines 220 could be replaced by separate bars secured to endpieces, providing the rotor is relatively short and not intended to rotate at high speed. In the embodiment shown, the cutout 250 is symmetrical about a midplane passing through the middle thereof and containing a radius. It has a bottom 251 for coming into contact with the radially outer face 221 of the corresponding spline 220. The bottom 251 connects opposite sides 252 each having a first rounded portion 252 a of radius of curvature Ra, an oblique rectilinear intermediate portion 252 b at a non-zero angle ii with the radius passing through the middle of the bottom 251, and a second rounded portion 252 c of radius of curvature Rc. In the embodiment described, Ra is 3 mm, Rc is 5 mm, and the angle ii is 70�. The cutout 250 has a narrow opening thus engaging on a spline 220. In general, the angle ii depends on the nature of the materials used for making the shaft 210 and the pole pieces 230, and it can be determined by computation using finite elements. The shape of the section of each spline 220 is substantially complementary to that of the cutout 252, excepting the presence of a chamfer 221 a at the edge of the radially outer face 221 of the spline 220. Each side 222 of the spline thus has a rounded portion 222 a having the same radius of curvature Ra as the rounded portion 252 a, a rectilinear portion 222 b parallel to the portion 252 b when the pole piece 230 is in place on the shaft 210, and a rounded portion 222 c having the same radius of curvature Rc as the portion 252 c. The radially inner edges 233 of the pole piece 230 situated on either side of the slot 250 are set back from the regions 213 of the shaft 210 situated between the splines 220, as can be seen in FIGS. 17 and 18, in particular. A gap 260 is thus left between two adjacent splines 220, the pole pieces 230 engaged on the splines, and the shaft 210. Permanent magnets 270 of trapezoidal section are disposed radially, being inserted between the pole pieces 230, as shown in FIG. 18. When observed along the axis of rotation of the rotor, each magnet 270 is slightly wedge-shaped, with its width tapering radially outwards. Each magnet 270 is magnetized transversely and can be formed as a single piece or it can be built up from a plurality of magnetic elements placed end to end. Same-polarity magnetic poles of two adjacent magnets 270 are directed towards the pole piece 230 situated between the magnets 270, as shown in FIG. 19. In the example shown, each magnet 270 is made up of three magnetic elements 270 a, 270 b, and 270 c placed end to end along the axis of rotation X of the rotor, as can be seen in FIG. 3. In the example shown, the magnets 270 extend over practically the entire radial size of the sides 238 of the pole pieces 230 and they are in contact therewith. The magnets present low electrical resistivity, but they are not subjected to heating that runs the risk of demagnetizing them because of the protection provided by the pole pieces against pulsating flux. The angle formed between the opposite plane faces of the magnets 270 that come into contact with the pole pieces 230 is quite small, being a few degrees only. The angle iii between the side 238 of a pole piece 230 and the adjacent edge 233 in the example shown in FIG. 16 is equal to 92.4�. The radially outer side 235 of a pole piece 230 is of circular cross-section, of radius of curvature that is smaller than the maximum radius of the rotor such that each pole piece 230 presents an outside face 235 which forms a slightly outwardly convex lobe, as can be seen in FIG. 18. The bulging shape of the pole pieces 230 makes it possible to reduce torque ripple and also to establish a flow of cooling air. In the example described, the shape of the lobe 235 and the ratio of the radial dimension of the magnets over their width is selected so as to have Lq=Ld so that the motor turns without the reluctance effect. Ld is inductance on the forward axis and Lq is inductance on the quadrature axis (traditional notation). The pole pieces 230 are arranged in such a manner that when the rotor 200 turns at a speed greater than a predetermined speed, the housings formed between said pole pieces 230 and receiving the magnets 270 tend to become wider under the effect of centrifugal force, with such widening tending to diminish when the speed of rotation decreases again. The radial size of the magnets 270 is selected in such a manner that when they are put into place in the corresponding housings in the rotor, their radially outer ends are set back from the radially outer edges of the pole pieces adjacent to the magnets. The magnets 270 are installed so as to engage in the gaps formed by the housings becoming enlarged in the manner described above when the rotor turns at a speed greater than said predetermined speed such that the pole pieces 230 clamp against the magnets 270 when the speed of the rotor drops back below said predetermined speed. The presence of the gaps 260 makes it easier to put the magnets 270 into place. It will be understood that this provides means that are simple and effective for pressing the magnets 270 against the pole pieces 230. To fix the magnets 270, the rotor 200 can be rotated at a speed that is 10% greater than its nominal speed of rotation, for example, or even 20% greater than said nominal speed. The magnets 270 are easily put into place since it is not necessary to insert them initially between the pole pieces 230 with any very great force, the final positioning of the magnets 270 taking place automatically when the rotor 200 is rotated. In addition, by causing the rotor to turn faster or slower, it is possible to obtain greater or lesser displacement of the pole pieces 230 and the magnets 270 and to act to a small extent on the outside diameter of the rotor. This can make it possible to make magnets 270 and pole pieces 230, and also the stator 100, using manufacturing tolerances that are much slacker, since it is possible to adjust the outside diameter of the rotor 200 to a desired value by causing it to rotate at a faster or slower speed. The magnets 270 present low electrical resistivity, but they are not subjected to heating that runs the risk of demagnetizing them because of the protection provided against pulsating flux by the pole pieces 230 at high speeds. The wedge-shape of the magnets 270 allows compression forces to be exerted on the portions of the pole pieces 230 that contain the splines 220 so as to tend to close the cutouts 250 onto the splines 220, with this effect being increased with increasing speed, such that the assembly is self-locking. The above-mentioned compression forces enable the width of the pole pieces on either side of a spline to be reduced, and thus make it possible to benefit from greater width in the connection between the spline and the shaft and thus make it possible for the shaft to be made out a material that is not mechanically as strong as non-magnetic steel, but is much less expensive and much lighter in weight, such as aluminum. The end cheek-plates 280 and 290 are fixed to the shaft 210 at opposite ends thereof to prevent the pole pieces 230 and the magnets 270 from moving axially. The cheek-plates define a stage of the machine. The rotor 200 can have a plurality of stages subdivided by intermediate cheek-plates, and the number of magnets 270 per stage can lie in the range 4 to 64, for example, possibly being equal to 8 as in the example shown for an 8-pole motor. When a plurality of stages are used and are separated by intermediate cheek-plates, the number of cheek-plates is preferably equal to the number of stages plus one. The cheek-plates 280, 290 can be made of aluminum, for example, or out of non-magnetic steel. The cheek-plates are fixed on the shaft 210 by means of bolts 281. Tapped holes 500 are made through the peripheries of the cheek-plates 280, 290 so as to enable balancing screws to be engaged. As can be seen in FIG. 13, in particular, the cheek-plate 280 has a circular radially outer edge 282 which is set back from the radially outer edge 235 of the pole pieces 230 and the radially outer edges of the magnets 270, which lie substantially level with the ends 235 a of the bulging faces. An annular zone A is thus provided around the cheek-plate 280 in which it is possible to read the magnetic field of the magnets 270 of the rotor by means of detectors 190 of the kind shown in FIG. 4. In FIG. 4, it can be seen that the detectors 190 can overlap the rotor 200 to a small extent because the cheek-plate 280 is in a slightly set-back position. In the embodiment described, there are three detectors 190, since the motor is a three-phase motor, with each detector comprising a Hall effect sensor arranged to detect the magnetic field over the peripheral region A of the rotor 200 around the cheek-plate 280. The magnetic field is read along an axis parallel to the axis of rotation of the rotor, the Hall effect sensor overlapping the peripheral region A. The detectors 190 are mounted on three consecutive teeth 130 of respective axes Zu, Zv, and Zw situated in the vicinity of the opening 111. In FIG. 4, it can be seen that the detectors 190 can overlap the rotor 200 to a small extent because the cheek-plate 280 is in a slightly set-back position. Each detector 190 is fixed by a screw 191 on a tooth 130 of the stator, said screw 191 being engaged in a hole 125. As can be seen in FIG. 4, each detector 190 extends along the radial axis Zu, Zv, or Zw of the associated tooth and passes through the coil 340 engaged on that tooth. The coils 340 are provided for this purpose with an inside section of length that is large enough to enable the detector 190 to be passed. The space left between a coil and the corresponding tooth for passing the detector can be about 5 mm, for example, with such a space serving to insulate the coil from the tooth where there is no insulation 349. It is advantageous to read the magnetic field of the permanent magnets 270 directly because that makes it possible to avoid adding special elements to the rotor whose sole purpose is to enable the angular position of the rotor to be read. This simplifies manufacture of the rotor and improves reliability. In addition, mounting detectors 190 in the gap between the coils 340 and the teeth 130 is particularly compact, while nevertheless providing easy access to the detectors 190 in order to replace them, should that be necessary. Each detector 190 is positioned inside a coil 340 of given phase. Each detector 190 makes it possible to detect which polarity of the rotor lies in register with the associated coil (and thus the corresponding phase) at a given instant. Each detector 190 delivers a high signal or a low signal depending on the polarity it detects. Each detector 190 has an electronic circuit for shaping the signals delivered by the Hall effect sensors so as to reduce sensitivity to interference. Depending on the position of the rotor, the various signals delivered by the detectors 190 can take up six possible combinations, each change in the triplet constituted by the states of the detectors 190 corresponds to a determined angular position of the rotor. This makes it possible to determine the angular position of the rotor at precise instants, and to compute the position of the rotor between these instants by interpolation, given knowledge of its speed. The coils can thus be excited in optimum manner with the desired amount of phase shift. The electrical current carried by each coil can thus be reduced to zero and change direction whenever a magnet lies on the axis of the corresponding tooth. Unlike a reluctance motor which operates in attraction only, the above-described motor operates both in attraction and in repulsion, and enables a large amount of torque to be generated. Each detector 190 also has a temperature sensor. Knowing the temperatures of the coils 340 of the various phases makes it possible to detect possible misfunction of the motor. On at least one of its cheek-plates 280 and 290, the rotor 200 has cooling fins 291 which can be seen in FIG. 1, in particular. It will be observed that an additional cooling effect is obtained by the presence of the lobes 235 formed by the pole pieces 230 at the periphery of the rotor, which make it possible to generate a flow of cooling air within the inside of the motor. The motor as described above in detailed manner presents numerous advantages, namely: its particularly compact structure enables it to be mounted in a cantilevered-out position at the end of a shaft, thus making it possible to reduce the number of bearings and to reduce mechanical losses due to friction, and also to reduce problems of lubrication; the rotor can turn at a high speed of rotation without running the risk of magnets becoming detached or of the magnets becoming overheated, since the magnets are little exposed to currents induced on the surface; the individual coils are easy to install and to replace, and there is no need to re-impregnate the stator; the mass of the magnets is quite small, and there is no need for them to be fractioned; the number of teeth and the number of coils is relatively small, thus facilitating manufacture; the heads of the coils are very short, thus making it possible to obtain a structure that is compact axially; the phases are separated electrically without contact and without crossover; the turns of the coils are touching, thereby ensuring that the slots are well filled; and torque ripple can be made negligible. The invention is not limited to a synchronous motor and it is also applicable to manufacturing a generator. The rotor can be internal or external. The electrical power of the machine can lie in the range 1 kilowatt (kW) to 750 kW, for example. The speed of rotation of the rotor can lie in the range 1000 rpm to 10,000 rpm, for example. A machine of the invention can also find applications when speed is below 1000 rpm. The outside diameter of the machine can lie in the range 50 mm to 1 meter (m), for example; in the most widespread applications, the outside diameter can lie in the range 100 mm to 600 mm. The invention is not limited to some particular number of poles nor is it limited to the stator being powered with three-phase AC. Electricity can be polyphase having nphases phases, where nphases is not equal to three. The shaft can be made out of non-magnetic materials other than aluminum, for example aluminum alloys. Although less advantageous, magnets in the form rectangular parallelepipeds or having some other shape could also be used, possibly in combination with magnets that are wedge-shaped. The teeth of the stator can have a face facing the rotor that is of a shape that is not circularly cylindrical about the axis of the rotor. The slots can be half-closed. claims Patent Citations
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According to the latest report from our Wireless Smartphone Strategies (WSS) service, global online channels will make up a significant 19% of all smartphone sales in 2015, of which pure e-retailers will contribute 8% of total global smartphone volume share. China and India lead the pack with the highest e-retailer share.
Jingdong is the largest e-retailer in China. In India, Flipkart remains the largest player.
Wireless Smartphone Strategies (WSS) clients can please click here to access the full report.
Samsung, the world's biggest smartphone vendor by volume, has officially announced a new duo of premium-looking metal smartphones, A3 and A5, at the end of October, 2014 and is planning on hard-launching them in November in select markets, mostly emerging markets, such as China at affordable price-points to address the mounting competition from local vendors. A3 and A5, which are the first two smartphones under the category of the new Galaxy A series, are believed to target the younger and first-time smartphone users in the growing emerging markets, with nice-looking metal unibody design, modest specifications and mid-ranged prices.
In addition to the metal design, it would be worth noting that these mid-priced smartphones are featuring 4G LTE connectivity and 5MP secondary camera, which is better than 3.7MP on more premium Galaxy Note 4. We believe that Samsung is taking on a selective marketing for the younger generation who wants to enjoy the faster data services on the faster 4G network, and spends much time to take the "selfie" photos in developing regions. There has been no words on the more advanced Galaxy A7 model, but will be expected to come with higher display resolution and stronger feature-sets later on.
May you live in interesting times as the old Chinese proverb goes. Well in the information, communication and entertainment industry we certainly do. Some very interesting questions face our industry whether we look at:
Every major technology advancement has lead to a massive disruption in the handset and infrastructure vendor community.
So how will the migration to 4G change the playing field?
I would welcome your thoughts on these key questions. Also don't forget to join our client webinar on Thursday May 27.
As we rapidly close the cover on one of the toughest years the telecommunications, content and internet industries have ever seen, SA takes a look ahead beyond the recession to detail the key megatrends for the mobile industry in 2010.
We see a tough but positive mobile ecosystem outlook with devices recovering stronger than services. More consolidation is likely among network operators, while profits for device vendors will continue to flow away from handset only vendors in favor of device/services integration specialists. Emerging markets will continue to dominate volume with strong 3G rollout competition expected. The global market for services, applications, devices and infrastructure will post modest growth of approximately 3% in 2010.
The total mobile industry revenue including services, infrastructure and devices was flat in 2009. We expect a modest growth of 2.8% in 2010 to $1140B.
· In 2009, only strong growth in data spends by users ensured that total industry revenues did not decline. Data revenues grew 9.5% in 2009 and are expected to grow at a 13% rate in 2010 reaching over $200B.
· Handset market sell through revenue will rebound well in 2010, posting growth of 4% while the infrastructure market will continue to struggle and will decline slightly.
Key issues shaping the 2010 landscape include:


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Mountain Horse Ladies Rimrock High Rider Winter Boot
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The Mountain Horse Ladies Rimrock High Rider Winter Bootis one of the Products of the Week for March 2013!Listen to this Radio Testimonialbrought to you by Horse Radio Network and Equestrian Collections. Mountain Horse Ladies Rimrock High Rider Winter Boot Mountain Horse Ladies Rimrock High Rider Winter Boot is a twist on an old classic. The boot is faux fur lined and waterproofed foot part that make this wonderful winter boot to keep you warm and dry. The shaft features a wide hook and loop closure that gives you a custom fit. It is made of a water repellent nylon that is soft and flexible. It features a reflective material insert for nighttime visibility. The entire shaft is faux fur lined and the faux fur insole is removable. The foot is a solid waterproof material. The sole has dirt repellent tread zone that helps to enhance your grip in the stirrups. The heel has an IPS shock system that absorbs shock while walking. Mountain Horse Ladies Rimrock High Rider Winter Boot offers:
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West Gunsight and Gunsight... | [ Sizes: Orig | Med | Small | Thumb ] | |||
West Gunsight and Gunsight peaks as seen from Kings Peak to the southwest. The shortcut for the standard route to Kings (the green line on this map), cuts across the south shoulder of West Gunsight. It is only really steep climbing up to the shoulder from Gunsight Pass. After that, it's just a stroll...until you get over to where you have to start climbing up Kings. June 2002. | Image Data
Image ID: 40899 Hits: 1250 Lat/Lon: 40.80320°N / 110.3517°W Object Title: West Gunsight and Gunsight... |


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Policy on Transfers and Plural Standing for Ministers
The requirements for men and women transferring into the Unitarian Universalist (UU) ministry, or applying for plural standing, are essentially the same as for other candidates. While transfer candidates can be assured that a Master of Divinity degree from an accredited theological school will be acceptable as academic background, additional work in the areas of Unitarian Universalist history, polity, traditions and religious education is expected. The core curriculum listed previously outlines the areas of knowledge and competency that are expected.
In addition, a clear demonstration of motivation and commitment to Unitarian Universalism must be expressed through participation in a local congregation and in area UU Ministers Association (UUMA) meetings and/or district meetings. (A minimum of 2 years involvement is expected by the Ministerial Fellowship Committee (MFC).) In many cases, successful completion of a CPE program and an internship or supervised ministry in a Unitarian Universalist congregation is also required. All transfer and plural standing candidates must be approved by a Regional Sub-Committee on Candidacy, complete the required reading list, participate in an approved career assessment program, and must meet with the MFC.
A person will officially be considered a Candidate for transfer or plural standing upon receiving the affirmation of the appropriate regional sub-committee and submitting the required materials to include:
- Initial Inquiry Form (RSCC-1);
- Interview Forms filled out by UU minister. (PDF) (RSCC-2)
- Essay on ministerial aspirations;
- Career assessment report;
- Official record of standing from previous/other denominational affiliation;
- Two letters of reference, one from a minister in good standing with previous denomination, and one from a denominational official attesting to the candidate's good standing (current or at time of termination.)
- Criminal Offense Disclosure Form; (PDF) (RSCC-3)
- Application for Candidate Status; (PDF) (RSCC-5)
- Consent for Release of Information. (PDF) (RSCC-4)
All transfer/plural standing applicants are required to sign a consent form allowing for the release of information from the previous/other denomination. (RSCC-4)
The MFC requires two years active involvement in a congregation. The following represent different ways to address this requirement. The more you can do the better!
- attend our General Assembly each June;
- attend your local Unitarian Universalist Association (UUA) District Assembly;
- develop a mentorship relationship with a UU minister in final fellowship, preferably face to face;
- consider attending a week long intensive at Meadville Lombard Theological School;
- attend a UU summer camp;
- attend a UUA Leadership School week, also often held in the summer;
- contact your local Unitarian Universalist Ministers Association ministerial chapter about possible involvement;
- consider supply preaching;
- lead adult religious education courses at a local UU congregation;
- join CLF, the Church of the Larger Fellowship;
- consider on-line UU coursework;
- consider doing another M. Div. Degree at a UU seminary!
Transfer and plural standing candidates should consult with the Ministerial Credentialing Director regarding specific requirements and paperwork expected by the Ministerial Fellowship Committee.
For more information contact firstname.lastname@example.com.


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Fear Itself: Wolverine #1
Posted on September 6th, 2011 by The Heroic AgeFear Itself: Wolverine #1
Amidst the unstoppable force of FEAR ITSELF tearing through New York City, Wolverine and his girlfriend, Melita Garner, find themselves having to make hard decisions in order to do what they do best. The British intelligence turned mercenary black ops group STRIKE has taken advantage of the chaos and activated sleeper agents for one final, deadly mission. It's up to Wolverine to stop them, but in leaving Melita to report from the ground, will his choice prove fatal?


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| Format | Pages | Price |   |
Hardcopy (shipping and handling) | 8 | $214.00 |   ADD TO CART |
Historical Version(s) - view previous versions of standard
1. Scope
The purpose of this method is to remove hydrogen sulfide and to reduce the mercaptan content in hydrocarbons, which are liquid at room temperature, by extraction with sodium hydroxide under standardized conditions. The treated distillate may be processed further in a pilot plant or tested for properties other than hydrogen sulfide and mercaptan content. Such additional processing or testing is beyond the scope of this method.
The results obtained by this method can also be correlated empirically with results from a commercial extractor as a check for extractor performance. When the characteristics of a given extractor are known in terms of this test, this procedure can be used to estimate results to be expected when extracting a new stock. This type of correlation is also beyond the scope of this method.
Citation Format
ASTM UOP547-13, Laboratory Hydrogen Sulfide and Mercaptan Extraction, ASTM International, West Conshohocken, PA, 2013, www.astm.org
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Keenum starter for Jacksonville game
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Site Contributor
Join Date: Oct 2011
Location: Elkhron, WI
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Re: Keenum starter for Jacksonville game
Originally Posted by
Mr teX
yeah....b/c everyone who watches football wasn't calling Blaine Gabbert trash after only a handful of few presesason & regular season games....Ditto for Geno Smith.
Bias on both sides of the fence around here.
while i agree there is bias around here, can anyone honestly say case has been given a fair shot? even at practice he splits time, so if he cant handle or read the hot route on the blitz its 100% garys fault for not teaching this. there is no reason to give schaub any reps in practice. meaningless wins by schaub in november are meaningless. give case 100% reps and let him try to get wins. the FUTURE of this organization is based on how case plays and improves. thats why gary and his bias should be fired now. he does not have our FUTURE in his current plans and if case is not our qb next year, this off-season is going to be rough. adding a legit qb to the list of needs will be devastating imo.
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Veterans of Foreign Wars Post No. 10281 Commander Butch Ferrell presents a check for $150 to Dodie Maier on behalf of USA Cares. VFW members voted to become a lane sponsor in the USA Cares Stars and Stripes Bowlathon to benefit post 9-11 military and their families through USA Cares programs, which consist of combat injured, jobs assistance, emergency assistance and housing assistance. If you currently subscribe or have subscribed in the past to the The News Enterprise, then simply find your account number on your mailing label and enter it below. Click the question mark below to see where your account ID appears on your mailing label.
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Editors' Note: The "Download Now" link directs you to the Android Market where you must continue the download process. This download may not be available in some countries.
Publisher's Description
+Mobile GPS tracking to locate silently: your family, your employees or your fleet of vehicles.Silently tracks a mobile and you can see where it is by accessing www.whereareyougps.com from your PC web browser. +400.000 tracked devices, now available on ANDROID! Try out our FREE Edition! What people are saying (check on BlackBerry Edition!):"I will never lose my handy again!!!" "Simple, runs silently and then log onto whereareyougps.com and you can see your movements plotted throughout the day and previous days!" This is the best tracker that I have ever downloaded and it is very accurate. Thank you very much."This app doesn't take up much space, doesn't show up unless you go digging for it, and is the perfect way for a parent to keep tabs on their children. It has highlighted deceit and allowed us to rectify the behavior without "appearing" overly invasive in their attempts to gain freedom. The best part about it is that it could help you find your child in an emergency, or if something were to happen.. .That is, until they'll let us inject them with a chip LOL This is by far one of the most useful parenting tools I've found..." "Found app easy to install and simple to track. Just use it people!" "May god bless the software designer... JUST TRY IT FOR FREE!! ***************************************INSTRUCTIONS / HOW TO INSTALLStep 1: Download WAY on the mobile which you want to track.Step 2: You will be asked to set an email and a password in order to register.And that's it! HOW TO TRACK THE DEVICE: Go to http://www.whereareyougps.com/ and enter the email and password you set while registering. View mobile positions on an interactive map. ***************************************GO TO A PREMIUM EDITION or a MULTI-USER EDITION:For Premium Edition (real-time minute capture interval, warning areas, up to 4 weeks location record ) and Multi-user Edition (more than one device, real-time every minute capture interval, warning areas, up to 6 months location record) : Step 1: Install the FREE Edition first Step 2: Go the Web Site www.whereareyougps.com Step 3: Login with the Email and Password you use in the Registration Form when you downloaded the AppStep 4: Click in GO PREMIUM! or GO ENTERPRISE!. If you need help, please contact: email@example.com Keywords:Phone Tracking, Mobile Tracking, Child Locator, Android Tracking, Vehicle Tracking, GPS Tracker, GPS Tracking, Tracker, Family Tracking, Tracking, Family Locator, Child Tracking, Lost Phone, Tracking Phone, Employees Tracking, Employees TrackerContent rating: Low Maturity


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Heheh, couldn't pass up the chance to use this.
Now, here's to hoping I manage to remember/make time to come up with something for the Calendar of Tales challenge! >_<;;
Like what you see? Feeling generous towards less-fortunate people? Have points you don't know what to do with? XDDD Please donate and help me raise 8000 points for a 12-month premium membership, so that I can sell prints, which in turn will help me pay my rent, feed myself and maybe buy other people's prints, too.. oh, and also to help me buy that really nifty digital artist bag from the DA shop. Ehehehe... ; Yeah, I'm totally pushing it. :3 BUT ENOUGH TALK. I SHALL CHARM YOU WITH MY AWKWARDNESS. <3 Please? Pretty please? <3 |


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Exercise in valvular heart disease: risks and benefits. | |
MedLine Citation:
PMID: 21545930 Owner: NLM Status: MEDLINE |
Valvular heart disease (VHD) carries documented risks for active individuals. At the same time, many individuals with intermediate degrees of valve disease can safely exercise and even participate in competitive athletics. Unfortunately for clinicians caring for these patients, data are scarce. Understanding the pathophysiology and natural history of VHD is key to applying consensus guidelines and making recommendations to individual patients. Careful physical examination and appropriate imaging studies will identify patients at risk; most will require serial evaluation but can exercise and participate in sports as desired. When symptoms develop, prompt treatment of severe, symptomatic disease and intensive cardiac rehabilitation as well as continued surveillance after surgical treatment will maximize the functional ability of active individuals with VHD. |
Matthew W Parker; Paul D Thompson |
Publication Detail:
Type: Journal Article; Review |
Journal Detail:
Title: Progress in cardiovascular diseases Volume: 53 ISSN: 1873-1740 ISO Abbreviation: Prog Cardiovasc Dis Publication Date: 2011 May-Jun |
Date Detail:
Created Date: 2011-05-06 Completed Date: 2011-07-19 Revised Date: 2013-05-02 |
Medline Journal Info:
Nlm Unique ID: 0376442 Medline TA: Prog Cardiovasc Dis Country: United States |
Other Details:
Languages: eng Pagination: 437-46 Citation Subset: AIM; IM |
Copyright Information:
Copyright © 2011. Published by Elsevier Inc. |
Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA. |
Export Citation:
APA/MLA Format Download EndNote Download BibTex |
MeSH Terms | |
Disease Progression Exercise / physiology* Exercise Therapy / methods* Heart Valve Diseases* / epidemiology, physiopathology, rehabilitation Humans Morbidity / trends Risk Factors United States / epidemiology |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Exercise therapy for cardiac transplant recipients.
Next Document: Benefits of exercise therapy in peripheral arterial disease.


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Enter Tobkio Rya Dojo. Your Journey to the Budokan begins here. Are you willing to endure the hard training it takes to be called a master?
Tobiko Sensei observes your every action. Go to him for words on tactics, strategy, and guidance. Put your philosophy into action.
Say hello to Goro-san. If you survive him, eleven others are prepared to teach you the zen of defeat. If you don't, it's konban-noa (goodnight!).
Do you fast attack for quick points or store up your ki (energy) for the devastating blow? Better decide before his Yari answers for you.
� Extensively researched and developed by qualified martial artists.
� Unique player interface allows for over 25 moves per style.
� Twelve authentic martial arts styles, including Yari, Tonfa, Kusari-gama and Naginata.
� Train and spar with the computer or a friend - but remember, you face the challange of the Budokan alone.
� Authentic digitized sound effects.


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Finite mathematics on-line topic: linear and exponential regression |
Note: The mathematics in this page has been typeset using jsMath. To see the jsMath typesetting at its best you should install the jsMath TeX fonts. Click on the jsMath button at the bottom right corner of this page for more details.
We have seen how to find a linear model given two data points: We find the equation of the line that passes through them. (See the Topic Summary of Functions for some examples.) However, we often have more than two data points, and they will rarely all lie on a single straight line, but may often come close to doing so. The problem is to find the line coming closest to passing through all of the points.
We start with an attempt to construct a linear demand function. Suppose that your market research of real estate investments reveals the following sales figures for new homes of different prices over the past year.
Price (Thousands of $) | 160 | 180 | 200 | 220 | 240 | 260 | 280 |
Sales of New Homes This Year | 126 | 103 | 82 | 75 | 82 | 40 | 20 |
We would like to use these data to construct a demand function for the real estate market. (Recall that a demand function gives demand y, measured here by annual sales, as a function of unit price, x.) Here is a plot of y versus x.
The data definitely suggest a straight line, more-or-less, and hence a linear relationship between y and x. Here are several possible "straight line fits:"
Q Which line best fits the data?
A We would like the sales predicted by the best-fit line (predicted values) to be as close to the actual sales (observed values) as possible. The differences between the predicted values and the observed values, called the residual errors (or just residuals) appear as the vertical distances shown in the figure below.
Q So how do we do that?
A We add up all the squares of the residual errors to get a single error, called the sum of squares error (SSE) and we choose the line that gives the smallest SSE. This line is called the best fit line, regression line, or least squares line associated with the given data.
So, for the line y = -x + 300
SSE | = | Sum of squares of residuals |
= | - 14 - 17 - 18 - 5 + 22 + 0 + 0 | |
= | -32 |
Q So that is to calculate SSE for a given line. How do we obtain the equation of the best fit line; the line that gives the lowest value of SSE?
A Following is the formula for the best fit straight line. To justify it requires some calculus. Consult the chapter on several variables in Applied calculus for a detailed explanation.
Regression (Best Fit) Line
The best fit line associated with the n points (x_1,y_1), (x_2,y_2), \dots ,(x_n,y_n) has the form
\text{Slope} = m = \frac{n\sum xy - \big(\sum x\big)\big(\sum y\big)}{n\sum (x^2) - \big(\sum x\big)^2}
\text{Intercept} = b = \frac{\sum y - m\big(\sum x\big) }{n}
Here, \Sigma means "the sum of." Thus \begin{align*}&\sum xy = \text{ sum of products }= x_1y_1+x_2y_2 + \dots + x_ny_n\\
&\sum x = \text{ sum of values of }x = x_1+x_2+\dots +x_n\\
&\sum y = \text{ sum of values of }y = y_1+y_2+\dots +y_n\\
&\sum x^2 = \text{ sum of values of }x^2 = x_1^2+x_2^2+\dots +x_n^2\\
Using the formula above is easy, as the following example shows.
\pmb x | 1 | 2 | 3 | 4 |
\pmb y | 1.5 | 1.6 | 2.1 | 3.0 |
Solution In order to apply the formula, it is best to organize the data in a table as shown. (When you have filled in the values of xy and x^2 correctly, press "Sums" to obtain the sum of each column.)
Substituting the correct values from the above table into the formula gives
Thus our least squares line is
Before we go on... Here is a plot the data points and the least squares line:
Notice that the line doesn't pass through even one of the points, and yet it is the straight line that best approximates them.
Let us now return to the data on demand for real estate with which we began this topic.
Find a linear demand equation that best fits the following data, and use it to predict annual sales of homes priced at $140,000.
Price (Thousands of $) | 160 | 180 | 200 | 220 | 240 | 260 | 280 |
Sales of New Homes This Year | 126 | 103 | 82 | 75 | 82 | 40 | 20 |
Solution Here is a table like the one we used above to organize the calculations.
\pmb x | \pmb y | \pmb {xy} | \pmb {x^2} |
160 | 126 | 20,160 | 25,600 |
180 | 103 | 18,540 | 32,400 |
200 | 82 | 16,400 | 40,000 |
220 | 75 | 16,500 | 48,400 |
240 | 82 | 19,680 | 57,600 |
260 | 40 | 10,400 | 67,600 |
280 | 20 | 5,600 | 78,400 |
\sum x = 1540 | \sum y = 528 | \sum xy = 107,280 | \sum x^2 = 350,000 |
Substituting these values in the formula gives (n = 7)
Notice that we used the most accurate value, m \approx -0.7928571429, that we could obtain on our calculator in the formula for b rather than the rounded value of -0.7929. This illustrates the following important general guideline:
Thus the regression line is
We can now use this equation to predict the annual sales of homes priced at $140,000:
Before we go on... Here is the original data, together with the least squares line.
Q If the given data points all happen to lie on a straight line, is this the line we get by the best fit method?
A Yes. If gte given points all lie on a line, then the smallest possible value of SSE is zero, attained by the line that passes through all the points. This has the following implication: you can use linear regression on a graphing calculator or the regression tool on this web site to check your calculations of the equation of a straight line passing through two specified points.
Q If the given points do not lie on a straight line, is there a way we can tell how far off they are from lying on a straight line?
A There is a way of measuring the "goodness of fit" of the least squares line, called the coefficient of correlation. This is a number r between -1 and 1. the closer it is to -1 or 1, the better the fit. For an exact fit, we would have r = -1 for a negative slope line or r = 1 for a positive slope line. For a bad fit, we would have r close to 0. The figure below shows several collections of data points with their regression lines and corresponding values of r.
The correlation coefficient can be calculated with the following formula. (To justify this formula requires a fair knowledge of statistics, so we shall not attempt do so here.)
Coefficient of Correlation
\text{Coefficient of Correlation }
= r = \frac{n\bigl(\sum xy\bigr) - \bigl(\sum x\bigr)\bigl(\sum y\bigr)}{\sqrt{n\bigl(\sum x^2\bigr) - \bigl(\sum x\bigr)^2}\cdot \sqrt{n\bigl(\sum y^2\bigr) - \bigl(\sum y\bigr)^2}}
Q Now we know how to fit a straight line to given data. What about an exponential curve of the form
Start with the exponential function
and take the logarithm of both sides:
The properties of logarithms give
This expresses \log y as a linear function of x, with
Therefore, if we find the best-fit line using \log y as a function of x, the slope and intercept will be given as above, and so we can obtain the coefficients r and A by
To summarize,
Exponential Regression
To obtain a best-fit exponential curve of the form y = Ar^x
Revenues from sales of Compaq computers (a brand now extinct) are shown in the following table, where t represents time in years since 1990.* Obtain an exponential regression model for the data.
\pmb t = Year (1990 = 0) | 0 | 2 | 4 | 7 |
\pmb R = Revenue ($ billion) | 3 | 4 | 11 | 25 |
Data are rounded. Source: Company Reports/The New York Times, January 27, 1998, p. D1.
Solution Since we need to model \log R as a linear function of t, we first make a table with x = t and y = \log( R, and then calculate the regression line, y = mx + b.
\pmb{x\ (= t)} | 0 | 2 | 4 | 7 |
\pmb{y\ (= \log R)} | 0.477121 | 0.602060 | 1.04139 | 1.39794 |
Instead of doing this calculation by hand as we did in the above examples, you can do it automatically using the on-line regression utility on this site. Just enter the x- and y-values in the table, and press the "y = mx+b" button. (Yes, that utility does exponential regression as well, but we would like you to know how it works!)
The linear regression model we obtain is
Thus, the desired exponential model is
This gives our revenue model as
Before we go on... Go to the on-line regression utility, enter the original data (before you took the logarithms) and press the "y = a(b^x)" button. What do you find?
Note: Since we have taken logarithms before doing the linear regression, it follows that the exponential regression curve does not minimize SSE for the original data; instead, it minimizes SSE for the transformed data --- that is, for the data (x, \log y). Thus, the exponential regression curve is not the best-fit curve in the "strict" sense. See the texbook "Applied Calculus" by Waner & Costenoble for a method to obtain such a best-fit curve.
On the TI-83/84, you will find all of these, as well as the following:
Last Updated: January 2008
Copyright © 2008 Stefan Waner


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In one of her first forays into the public eye since the fallout over her husband's love child scandal, Maria Shriver took to her blog on Friday.
A member of the International Board of Special Olympics, Shriver, 55, wrote about how she can relate to the athletes participating in the Special Olympics World Games, which kick off Saturday in Athens.
"My friend, Special Olympian Eddie Barbanell, wrote me a beautiful note before I traveled to Athens that made me feel so good," she blogged. "He said that he knew I was going through a rough time but he wanted me to know that I 'will never be left out.'"
"Special Olympians, and people with intellectual disabilities in general, have experienced the feeling of being left out over and over again," Shriver wrote. "This makes them wise teachers on this topic. I thought it was poignant that Eddie was the one who delivered this message to me."
"Thousands of people – family, friends, neighbors, colleagues and many people I've never met – have reached out to me recently with loving, uplifting, hopeful and kind messages," she continued. "But he was the only one who wrote, 'You will never be left out.'
Looking forward to Saturday night's Opening Ceremony and the parade of 7,000-some athletes, Shriver added that being in Athens, "There is an incredibly strong spirit of unity here. My brother, Tim, talks often about launching a 'Dignity Revolution' throughout the world and you can definitely feel that in the air."
Maria Shriver: How I Relate to Special Olympians
Ian Lawrence/Splash News Online


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EOS Berry Blossom Everyday Hand Lotion Review
If you follow me on Twitter you know I preach the good word of Sheppard (More Romo, more Romo!) to anyone who will listen. Hell, I preach it to @BBCAmerica and remind them daily how much I appreciate his voice over work for the channel.
Thank you BBCAmerican Gods for gifting us with the divine vocal voice over work of Mark Sheppard, praise Jebus, thank Gawd, Amen! P.S. Please ask the Supernatural Gods to not let Bobbi die, k, thanks.
I came across a rather brilliant T-Shirt on RedBubble last month and instantly had to add it to my fandom palace. Behold SuperWho fangurls:
I know SuperWho fangurls like myself are out there so this one is for you! You NEED this shirt.
Speaking of fangirls…I happen to be a fangirl of EOS as well as Who and Supernatural.
The first time I tried EOS Everyday Hand Lotion I fell in love but I quickly wanted to re-adjust the product to better suit my needs….as in I wanted a Summer Fruit or Mint version of this gorgeous hand lotion or even a Lemon version!
The fragrance selection was limited to a mere two scents that included cucumber or fresh scent. Blah!
I need variety in my beauty loving life.
The EOS Gods have responded and thus Berry Blossom Everyday Hand Lotion came to be.
EOS Everyday Hand Lotion is a super product to tuck into your purse or have on your desk for quickie hydrating as it contains a blend of skin loving ingredients like shea butter and aloe.
There are alot of awesome things about this little hand cream. The portable size, the cute squeeze tube that distributes just the right amount of hand cream out, the soft, moisturizing formula which never leaves hands feeling greasy, sticky, or oily and absorbs in a snap leaving my hands touchable and smooth and now we have a new Berry scent to really make things awesome.
Or not…
I'm not particularly keen on the Berry Blossom scent so I think I'll stick to the Fresh and Cucumber versions. This is a strong scent that wouldn't necessarily bother me if I liked it but since I'm not really loving the smell I find it gives me a little bit of a headache. If you're sensitive to fragrance in your skincare products or just sensitive to fragrance on a whole be aware as this is a bit of a stronger scent.
There's definitely berry in the mix but they combine it with floral which is when it goes wrong for my nose. I feel like it smells like some sort of shampoo but not in a pleasant way.
Scent is a deeply personal thing and it'll vary from person to person so you might just love Berry Blossom but as for me, no likey!
Please EOS consider a Summer Fruit, Mint, or Lemon version of your hand lotion! I'll buy!
Anyone try?
Do share!
This review contains a sample product sent for consideration by PR.
Read my full disclosure statement here.
12/9/11 11:32 InTheClouds:
I bought one too thinking a fun berry scented lotion and I too was not a huge fan of the smell. At first the scent is not terrible, it's alright. But then it just lingers and lingers forcing me at one point to wash my hands. I was somewhat disappointed with this one.
12/9/11 11:33 the Muse:
agreed…it kinda smells like a shampoo!? but not a pleasant type of scent…just a bit overpowering…!
12/9/11 11:51 Kimryan8:
Hi Muse!
OMG I adore your mix of nerdery with cosmetics! You always make me laugh!
12/9/11 11:54 the Muse:
haha kim are you a superwho? ;D!
12/9/11 12:29 Kimryan8:
No, my husband (the nerd) is. I just know about it because he loves Dr. Who. He and his friends are tyring to get me to watch it all the time.
12/9/11 12:31 the Muse:
you need to watch it! go watch it! come back tell me whatcha think! Start with the Tom Baker years ;D!
12/9/11 12:34 Kimryan8:
I use most of my spare time making cards for my Etsy shop – I get annoyed when he tries to get me hooked on another series because I always end up liking them. The last one I refused and caved on was Battlestar Gallactica and we were obsessed.
12/9/11 12:37 the Muse:
you have to tell me more about your etsy shop! what kind of cards!? BG is MY FAV evahzzzzzzzz!
12/9/11 12:47 Kimryan8:
Well now I can match your nerdery – my brother in law has the BG boardgame. We set up a whole day where we get 8 people together and drink beer & eat appetizers and play. It takes like 8 hours to play! Its so much fun! I am a terrible Cylon
I make stamped and letterpress cards and use lots of glitter. I do special orders & invites too. If you get a minute, check out my shop – its nothing cosmetics oriented though so I didn't respond when you were asking for the Etsy shops a few weeks ago.
12/9/11 12:55 the Muse:
ha that's brilliant can I come over? We do old style D&D parties every few months, yes, I am that dorky.
I love cards/stationary! I'm going to go visit now brilliant ;D!
12/9/11 12:55 the Muse:
ps looking now these are stunning!
12/9/11 13:01 Kimryan8:
Wow, thanks Muse. You always brighten my day. You can come over for BSG board game day anytime! You'll have to fly to Chicago tho…
12/9/11 13:04 the Muse:
chi-town! my fav city ;-D I'll be RIGHT over! I'm looking at your cards still! loving the pooh! ;-D!
12/9/11 13:05 Kimryan8:
We got our first dusting of snow last night. I am sure NYC will be next!
12/9/11 13:09 the Muse:
I HOPEEEEEEEEEEEEE! but dude it's way colder over yonder! You get some major wind!
12/9/11 13:11 Kimryan8:
Sadly, the weather does suck.
12/9/11 13:16 the Muse:
doesn't feel like Christmas at all here a little snow would be nice!
12/9/11 13:18 Kimryan8:
Ok – slow day for me (obviously) I'm in the insurance biz like you. My hubby wants to know if you've collected all the riddler trophies
12/9/11 13:23 the Muse:
that's brilliant! what type of insurance? we specialize in commercial liability ;-D no way there are over 400! some of them are in stealthy azz locations too! I was trying to void the online guide, g4 has a cool guide for discovering them but I wanted to be surprised…but that's complete shat as I'll never be able to discover them all without the use of the guide ;-D!
12/9/11 13:30 Kimryan8:
Commercial insurance too- I work at an agency. We mostly handle contractors.
12/9/11 13:35 the Muse:
that's pretty cool to meet someone in ins. too! I do a few contractors but it's a bit slow with the economy. We work with individual self employed contractors, paints, etc…nothing major!
12/9/11 13:42 Kimryan8:
There is a huge roadbuilders assoc. Christmas party/awards party that is held every year and it was last night. HUGE deal in our industry in Chicago – that could account for the slow day since everyone is, ahem, sleepy…
12/9/11 13:56 the Muse:
parteeee! and lots of hangovers! at least the weekend looms ahead! Do you guys work with American Country/Atlas ? They are located in Illinois. About…mmm 30 mins from Chicago.
12/9/11 14:01 Kimryan8:
No, not that I am aware of. I specifically do surety/bonds so I am not so in tune to the property and casualty carriers anymore. I love surety so much more than the frustrations of insurance!
12/9/11 14:24 the Muse:
god I wish I did surety only. They are such a joy! ha be funny if I did a bond with you. I normally do them with Bernard Fleisher and Sons or Thompson Agency.
12/9/11 14:31 Kimryan8:
That would! We have a few large national contractors that need bonds all over, but rarely do we enter New York. Tough market… Legal environment is severe! I'll remember to contact you if I get into a countersignature situation. It is harder and harder to find agent's who will do that. Most states have repealed the requirements but if the contract still requires it, we have to do it!
Hey – I have an actual makeup question for you, I love UD 24/7 liners, but lining the inner rim of my eye gets my contacts all sticky and blurry. Do you have any contact lens friendly eyeliners for waterline? What have other people said?
12/9/11 14:49 le:
I personally don't like EOS lip balms, but this hand lotion has a very cool design and is convenient to carry along. Do you think I might enjoy it?
Like the way you start your review, so interesting-
12/9/11 14:55 the Muse:
hi le I'm not sure hun depends on how you feel about the scent. I personally like the cucumber and fresh one, this one I didn't enjoy.
12/9/11 15:38 Littlecreek:
Hello le! The lotion is great. As she said, it absorbs quickly and doesn't leave your hands feeling slick. And at the low price it's worth trying.
12/9/11 19:42 Marty Pauline:
WooHoo for SuperWho! Will have to give EOS a try.
12/13/11 9:56 the Muse:
LOL Marty are you a Superwho?
12/13/11 8:34 Renee:
The cucumber smell great, along with the original. I recently bought the full-size bottle for the original 8D~
12/13/11 13:43 Karina A.:
I agree with you about the scents. Yes berry please!
It's so great to meet another SuperWho who also loves makeup!
I need Cas and Bobby to come back.
P.s. Can Mark Sheppard adopt me, please?-
12/13/11 13:45 the Muse:
lol and when he adopts you maybe you can sleep in the same bed as him yes please…yes please..LOL
I heard a rumor that Cas might come back! ;-D Bobbi awww I hope they don't kill him off, those boys need a father figure in their lives!


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by Jonathan Berr | January 6, 2012 7:30 am
When describing his plan to jump-start the U.S. economy, the website of GOP presidential[1] candidate Rick Santorum waxes poetic when it speaks of his vision "to restore America's greatness through promotion of freedom and opportunity for all." Unfortunately, many experts argue it won't do anything of the sort.
Like the other Republican candidates, the former Pennsylvania senator, whose strong second-place showing in Iowa[2] rocked the party's political Establishment, believes taxes are too high and government is too big. Santorum is calling for two-tiered tax rate system on personal income taxes and wants to slash the corporate tax rate from 35% to 17.5%, to make U.S. business more competitive globally.
Other highlights of his plan include eliminating the corporate income tax for manufacturers. In addition, he calls for ending the so-called marriage penalty and for tripling the personal deduction for each child. The fact that Santorum is a father of seven and a foe of abortion might explain that unusual proposal.
"In Rick Santorum's world, married couples with a gaggle of children will rule. It's as if Santorum wants to turn back the clock 40 or so years by using economic policies to encourage Americans (heterosexual Americans, that is) to marry and produce children," writes Nancy Cook at the National Journal.[3]
During his 16-year career in the U.S. Congress, Santorum generally earned kudos for his stance on fiscal issues from conservative groups such as the Club for Growth and the National Taxpayers Union, which rated him above average compared with other Republicans. He consistently "supported broad-based tax cuts and opposed tax increases," according to the Club For Growth's website[4].
Still, the organization's take on Santorum is hardly enthusiastic, calling his spending record "mixed." "As president, Santorum would most likely lead the country in a pro-growth direction, but his record contains more than a few weak spots that make us question if he would resist political expediency when it comes to economic issues," the group says.
His current policies aren't winning Santorum friends among fiscal conservatives.
Santorum's plan is generous to a fault, light on specifics and needs to pare his tax breaks with corresponding spending cuts, according to Will McBride, an economist with the Tax Foundation[5], which gave the candidate's plan a "D+" — the lowest grade of any of the GOP presidential contenders.
"It would result in much lower revenues," McBride says, adding that not having the spending cuts would make Santorum's plan "not fiscally conservative or responsible. His tax cuts don't clearly lead to economic growth."
According to McBride, Santorum hasn't elaborated on which taxpayers in what brackets would pay for the 10% and 28% rates under his plan. His proposal to eliminate corporate taxes for manufacturers will lead to large number of businesses in divergent industries claiming to be manufacturers, potentially depriving the U.S. Treasury of hundreds of billions revenue.
"This is unprecedented, and we don't know what would happen," McBride says.
Howard Gleckman of the Tax Policy Center argues that Santorum's proposal to slash federal spending by $5 trillion over five years would harm many of the same families who would benefit from his tax breaks because of the cuts Santorum's plan would make to domestic programs such as Medicaid and food stamps.
"Interestingly, by using tax expenditures to support these families, Santorum would likely add significantly to the number of households that pay no income tax," he writes in a blog post[6]."If he somehow gets the nomination, he'll still have to explain the huge hole he'd blow in the budget."
In an interview, Gleckman says he can't provide more specifics about Santorum's plan because it lacks sufficient data. An email to the Santorum campaign wasn't immediately returned.
Source URL: http://investorplace.com/investorpolitics/rick-santorum-tax-plan-gop-presidential-campaign/
Short URL: http://investorplace.com/?p=87964
Copyright ©2015 InvestorPlace Media, LLC. All rights reserved. 700 Indian Springs Drive, Lancaster, PA 17601.


text:
Went to Mall-mart and got some makeups
FollowWent to Mall-mart and got some makeups
I got this mini dry shampoo in my violet voxbox! I'm excited to try it out! :)
Look what finally came in the mail! 💕
My sister and I got matching tattoos 💕
My sister went to the thrift store today and found three brand new beauty blenders for 50 cents! 50 CENTS FOR ALL OF THEM! She was nice enough to give me one too! :)
Edited this because it looks weird without it, anyways. I get two new perfumes! :)
Did my own acrylics today, I'd say it was a win 💅
My sister got me this super cute necklace!! :)
I had to post this! This is my bestfriend and this is her makeup for Halloween!!
Went to VS yesterday and thought this was cute sooo yeah


text:
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Thanks for the answers....I thinK? lol
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The Squire
Got Wood.
Join Date: 03-01-07
Location: Smithtown, NY
Thanks MR.Mike
Wow, so you dont use a lot of Propane. That would suck though if you lower the heat and the flame goes out for all those hours..lol.
Yea, the fellas mentioned a metal smoker box and fill it with damp Mesquite chips. The whole slow and low deal I believe definately has to be a whole day thing. Watching the cooking like the guys in KC and down south, ya know?
What foods could you do the whole Mesquite chip thing with?
I would think steaks wouldn't go well with that smoker?
Stuff like Braut and Kilbassie and stuff?
I would like to try it this summer, but do a Mesquite smoking for like 2 to 3 hours tops...is it possible?
With wet chips in tinfoil and holes punched in them.
Seriously guys, what would be a good starting food for a beginner with the smoker technique and a good recipe you recommend.
Thanks for all the help.
The Squire
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text:
Will this film cutout around the home button area cover the detection ring on the 5s, thus interfering with the finger print recognition?
- Asked by Edwin K from Markham
Belkin Anti-Glare Screen Overlay for iPhone 5
Product No Longer Available
1 Answer from the Community
I can confirm I have fitted this film to a 5s with no interference to the Touch ID.
- Answered by Stephen T


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Welcome! You are browsing as a guest
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© purlbuttons
North Shore Pullover
Pattern number GU422
Pattern Description
This smart-looking pullover features five different knit/purl stitch patterns. Knit in DK or worsted weight yarn.
Yarn Requirements
Pattern may be knit in DK or worsted weight yarns.
Materials for worsted weight yarns: 1375-2275 yards worsted weight yarn, US 8 and 6 needles. Gauge 18 st/4 inches.
For more information, see:


text:
(18 quotes found)
"The net effect of that is very difficult to know since we don't know the magnitude of the Saturn cuts. How many jobs that plays out to be in the end, we don't know."
Bill Fox
"Initial reports are that the Saturn failed to stop at a stop sign or just didn't see the truck coming and pulled out in front of it."
Brad Arnold
"Johnson Controls is pleased to be providing electronics to the all-new Saturn Outlook."
Brian Kesseler
"taking advantage of what we put together in that Saturn 5 rocket. If we had chosen to put wings on that Saturn, we might have been on the way. But then the Russians might have got to the moon first."
Buzz Aldrin
"We are already learning new things about the Saturn system. We will fly by Phoebe on June 11th and that's a very interesting moon. We presume that it's a captured object. We don't know what population it represents. Is it an asteroid? Is it a Kuiper Belt Object?"
Candice Hansen
"We've been on the lookout for them since February, 2004. Spokes are one of those Saturn-system phenomena that we are keenly interested in understanding."
Carolyn Porco
"While I was there, Voyager flew by Saturn. I got involved with a person who was a member of the imaging team and started working on data from Saturn, ... With all that data coming in, the imaging team didn't have enough hands or scientists to work on all of it."
"It's been an adventure just getting out to Saturn, ... Saturn is such an alluring photographic target. It's a joy, really, to be able to take our images and composite them in an artful way, which is one of my cardinal working goals. It's about poetry and beauty and science all mixed together."
"Saturn is the most photogenic planet in the solar system."
"Saturn has been a laggard when it comes to new vehicles, so expanding the lineup is a good sign. One of the criticisms is that GM targeted Saturn to fight the Japanese but without expanding the lineup, they've lost buyers."
Catherine Madden


text:
Title: | Synthesis, Spectral Characterization, Structural Studies and Biological Investigations of Transition Metal Complexes of Some Acid Hydrazones |
Author: | Sreeja,P B; Prathapachandra Kurup, M R |
Abstract: | This study concentrates the chemical properties of hydrazones due to its chelating capability and their pharmacological applications. Studies cover the preparation of different acid hydrazones and their structural studies and studies on their antimicrobial activity, synthesis and spectral characterization of different complexes of copper oxovanadium, manganese, nickel etc. Effect of incorporation of heterocyclic bases to the coordination sphere, change in the biological activity of acid hydrazones upon coordination, development of X-ray quality single crystals and its X-ray diffraction studies, studies on the redox behavior of the coordinated metal ions and correlation between the stereochemistry and biological activities. |
URI: | http://dyuthi.cusat.ac.in/purl/18 |
Date: | 2004 |
Files | Size | Format | View | Description |
Dyuthi-T0290.pdf | 2.589Mb |
View/ |


text:
Sunday's game at the Stadio Olimpico was stopped by officials after eight minutes because of a waterlogged pitch, with the score goalless.
The Lega Serie A announced in a statement on Tuesday that the Serie A encounter will take place on April 2 if Roma's city rivals Lazio do not need the stadium for a Europa League game that same day. Otherwise, the encounter will be played on April 9.
Roma are second in the standings, nine points adrift of league leaders Juventus but have a game in hand.
New Sky Bet customers: Free £30 matched bet


text:
Best Answer James B† , 11 March 2014 - 12:57 AM
Any editing to the functions.php which isn't correctly coded will unfortunately bring the site down, you'll need to go in via ftp or cpanel and edit the code out of the file to get it back up and running. Sometimes the plugin author will provide you with the correct code for the wp hook if you state to them what you need etc.
Go to the full post


text:
Mode competition in high power fiber amplifiers |
Optics Express, Vol. 19, Issue 12, pp. 11318-11329 (2011)
Enhanced HTML Acrobat PDF (1097 KB)
Using a beam propagation model of Yb3+ doped, CW fiber amplifiers we show that gain saturation by a strong fundamental mode significantly suppresses the growth of higher order modes with parallel polarization, but enhances the growth of higher order modes with perpendicular polarization. We quantify this effect in straight and bent fibers, with full core or restricted area doping.
OCIS Codes
(140.3280) Lasers and laser optics : Laser amplifiers
(140.3510) Lasers and laser optics : Lasers, fiber
(140.3615) Lasers and laser optics : Lasers, ytterbium
ToC Category:
Lasers and Laser Optics
Original Manuscript: April 11, 2011
Revised Manuscript: May 17, 2011
Manuscript Accepted: May 18, 2011
Published: May 25, 2011
Arlee V. Smith and Jesse J. Smith, "Mode competition in high power fiber amplifiers," Opt. Express 19, 11318-11329 (2011)
Sort: Year | Journal | Reset
- A. V. Smith and J. J. Smith, "Mode instability in high power fiber amplifiers," Opt. Express 19, 10180–10192 (2011). http://www.opticsinfobase.org/abstract.cfm?URI=oe-19-11-10180 . [CrossRef] [PubMed]
- J. B. Spring, T. H. Russell, T. M. Shay, R. W. Berdine, A. D. Sanchez, B. G. Ward, and W. B Roh, "Comparison of stimulated Brillouin scattering thresholds and spectra in nonpolarization-maintaining and polarization-maintaining passive fibers," Proc. SPIE 5709, 147–156 (2005). [CrossRef]
- R. H. Stolen, "Polarization effects in fiber Raman and Brillouin lasers," IEEE J. Quantum Electron. QE-15, 1157–1161 (1979). [CrossRef]
- Z. Jiang and J. R. Marciante, "Impact of transverse spatial-hole burning on beam quality in large-mode-area Yb-doped fibers," J. Opt. Soc. Am. B 25, 247–254 (2008), http://www.opticsinfobase.org/abstract.cfm?URI=josab-25-2-247 . [CrossRef]
- S. Liao, M. Gong, and H. Zhang, "Influence of mode distortion on the transverse mode competition in large-mode-area amplifiers," Opt. Commun. 282, 406–412 (2009), http://linkinghub.elsevier.com/retrieve/pii/S0030401808010067 . [CrossRef]
- J. Marciante, "Gain filtering for single-spatial-mode operation of large-mode-area fiber amplifiers," IEEE J. Sel. Top. Quantum Electron. 15, 30–36 (2009), http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=4773298 . [CrossRef]
- S. Liao, M. Gong, and H. Zhang, "Theoretical calculation of beam quality factor of large-mode-area fiber amplifiers," Laser Phys. 19, 437–444 (2009), http://www.springerlink.com/index/10.1134/S1054660X09030141 . [CrossRef]
- M. Gong, Y. Yuan, C. Li, P. Yan, H. Zhang, and S. Liao, "Numerical modeling of transverse mode competition in strongly pumped multimode fiber lasers and amplifiers," Opt. Express 15, 3236–3246 (2007), http://www.opticsinfobase.org/abstract.cfm?URI=oe-15-6-3236 . [CrossRef] [PubMed]
- T. Bhutta, J. I. Mackenzie, D. P. Shepherd, and R. J. Beach, "Spatial dopant profiles for transverse-mode selection in multi-mode waveguides," J. Opt. Soc. Am. B 19, 1539–1543 (2002), http://www.opticsinfobase.org/abstract.cfm?URI=josab-19-7-1539 . [CrossRef]
- J. Sousa and O. Okhotnikov, "Multimode Er-doped fiber for single-transverse-mode amplification," Appl. Phys. Lett. 74, 1528–1530 (1999). [CrossRef]
- N. Andermahr and C. Fallnich, "Interaction of transverse modes in a single-frequency few-mode fiber amplifier caused by local gain saturation," Opt. Express 16, 8678–8684 (2008), http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-12-8678 . [CrossRef] [PubMed]
- N. Andermahr and C. Fallnich, "Modeling of transverse mode interaction in large-mode-area fiber amplifiers." Opt. Express 16, 20038–20046 (2008), http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-24-20038 . [CrossRef] [PubMed]
- D. Vysotsky and A. Napartovich, "Mode competition in steady-state optical waveguide amplifiers," J. Exp. Theor. Phys. 108, 547–556 (2009). http://dx.doi.org/10.1134/S1063776109040013 . [CrossRef]
- J. W. Nicholson, A. D. Yablon, S. Ramachandran, and S. Gaalmi, "Spatially and spectrally resolved imaging of modal content in large-mode-area fibers," Opt. Express 16, 7233–7243 (2008), http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-10-7233 . [CrossRef] [PubMed]
- T. Eidam, S. Hadrich, F. Jansen, F. Stutzki, J. Rothhardt, H. Carstens, C. Jauregui, J. Limpert, and A. Tunnermann, "Preferential gain photonic-crystal fiber for mode stabilization at high average powers," Opt. Express 19, 8656–8661 (2011). http://www.opticsinfobase.org/abstract.cfm?URI=oe-19-9-8656 . [CrossRef] [PubMed]
- D. Marcuse, Theory of Dielectric Optical Waveguides , 2nd ed. (Academic Press, 1991).
- J. Koplow, D. Kliner, and L. Goldberg, "Single-mode operation of a coiled multimode fiber amplifier," Opt. Lett. 25, 442–444 (2000), http://www.opticsinfobase.org/abstract.cfm?URI=ol-25-7-442 . [CrossRef]
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© Jil Eaton
A great dress up cardigan for ages 2 to adult. solid color with dark trim, add metal buttons for the nordic look. quick knit in garter stitch.