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An integrated circuit distributed radio frequency oscillator comprises a semiconductor chip which includes a differential input transmission line, a differential output transmission line and, coupled in parallel between these transmission lines at spaced apart portions, a number of differential amplifier cells with adjustable delay. The output end of the output transmission line is coupled back to the input end of the input transmission line by a feedback link with a pair of on-chip capacitors. The delay introduced by the amplifier cells is variable in response to a tuning voltage applied to a differential tuning input, making the oscillator suitable for use as a distributed VCO in, e.g. a phase-locked loop circuit. The layout of the oscillator on a semiconductor chip includes the series-connected arrangement of the differential transmission lines in a rectilinear spiral path.
1. A method of modeling a monolithic distributed VCO to operate at a given frequency of oscillation, the VCO model having a spacing topology defined by an input differential RF transmission line pair series-disposed so as to form a rectilinear spiral relative to an output differential RF transmission line pair spaced a predetermined (X) distance apart and defined by associated conductor widths and spacings Wb, Wc, Sb, Sc and connected at a common end thereof to a pair of MIM capacitors, and a plurality of differential amplifier cells distributed along the rectilinear spiral and separated a first distance lb apart relative to the length of the input differential RF transmission line and a second distance lc apart relative to the length of the output differential RF transmission line, the method comprising:
selecting values for X, Wb, Wc, Sb, Sc, lb, and lc; and
identifying when the selected values cause the VCO model to oscillate at a desired frequency range.
2. The method of
3. The method of
4. An integrated circuit comprising:
a distributed voltage controlled oscillator (VCO), wherein a frequency of oscillation of the VCO is defined by a spacing topology of:
an input differential RF transmission line pair (14) series-disposed so as to form a rectilinear spiral relative to an output differential RF transmission line pair (16) spaced a predetermined distance apart and defined by associated conductor widths and spacings Wb, Wc, Sb, Sb, and connected at a common end thereof to a pair of MIM capacitors, and a plurality of differential amplifier cells (18-1, 18-2, 18-3, 18-4) distributed along the rectilinear spiral and separated a first distance lb apart relative to the length of the input differential RF transmission line and a second distance lc apart relative to the length of the output differential RF transmission line, each differential amplifier cell is a variable delay element and includes a voltage-controlled input to fine tune and adjust the frequency of oscillation in a highly linear manner during operation of the VCO.
5. The integrated circuit of
6. The integrated circuit of
a circuit pair of differential output lines, each coupled to a respective conductor of one of the differential RF transmission lines;
a cross-coupled transistor pair having a pair of output terminals each of which is coupled to a respective one of the differential RF transmission lines; and
a current apportioning circuit to vary the ratio of dc supply currents drawn by the circuit pair and the cross-coupled transistor pair respectively in response to a tuning signal being received at the voltage-controlled input.
7. The integrated circuit of
8. The integrated circuit of
9. A radio frequency communication system, comprising:
a VCO having an operating frequency range in excess of 1 GHz, the frequency of oscillation of which is defined by a spacing topology of:
an input differential RF transmission line pair (14) series-disposed so as to form a rectilinear spiral relative an output differential RF transmission line pair (16) spaced a predetermined distance apart and defined by associated conductor widths and spacings Wb, Wc, Sb, Sc, and connected at a common end thereof to a pair of MIM capacitors, and a plurality of differential amplifier cells (18-1, 18-2, 18-3, 18-4) distributed along the rectilinear spiral separated a first distance lb apart relative to the length of the input differential RF transmission line pair and a second distance lc apart relative to the length of the output differential RF transmission line pair, each differential amplifier cell is a variable delay element and includes a voltage-controlled input to fine-tune adjust the frequency of oscillation in a highly linear manner during operation of the VCO.
This invention relates to an integrated circuit distributed oscillator and, in particular, to a distributed radio frequency (RF) oscillator having differential input and output transmission lines which are interconnected.
Optical telecommunications, satellite telecommunications and microwave wireless links require the use of RF analogue circuits such as lumped amplifier circuits and, especially, voltage-controlled oscillator circuits operating at very high frequencies, e.g. upwards of 1 GHz or 10 GHz. Such circuits form the core of these systems. For the implementation of such circuits, advanced semiconductor technologies using group III/group V semiconductor compound devices or advanced silicon devices are preferred.
Group III/group V semiconductor structures, although achieving high performance with respect to speed and frequency, suffer from high production cost, low yield, and low integration capability. As a result, application costs are high, and development times are long.
Advanced silicon technologies, such as 90 nm RF CMOS or 0.13 μm SiGe BiCMOS offer lower costs and large scale integration, but suffer from poor performance at the high frequencies mentioned above when compared with the corresponding devices using III/V semiconductor compounds. The reasons for this reduced performance are the lower quality of the passive components (inductors, resistors, capacitors) used for the above-mentioned implementations, the lower quality of interconnects, as well as the existence of effects such as substrate coupling. According to ITRS 2005 (International Technology Roadmap for Semiconductors Report 2005) the further shrinking of circuit structures based on silicon technologies, as well as the proposed solutions for the interconnections problem, do not seem capable of bringing the desired improvement in these implementations. Furthermore, the use of nanotechnology is not foreseen to become feasible in economic terms in the near future.
It is known to use distributed circuits in the frequency regions referred to above. The ability of these circuits to absorb the parasitic capacitances of input and output stages, along with the linear signal superposition effect, are characteristics that allow the specific distributed circuits to offer a higher gain-bandwidth product compared to lumped implementations, see A. Hajimiri, "Distributed Integrated Circuits: An Alternative Approach to High-Frequency Design," Invited Paper, IEEE Communications Magazine, vol. 40, no. 2, pp. 168-173, February 2002.
The first distributed circuit and the associated theory was presented by W. S. Percival in 1937, see British Patent No. 460,562. This disclosed a microwave amplifier based on vacuum tubes or valves. Such valve circuits were widely used in CW radars after World War II, and were the forerunners of existing distributed circuit RF front-ends for microwave links and satellite systems, and laser drivers.
The majority of such systems have been implemented either with printed circuit boards or with advanced III/V semiconductor structures. The cost of the circuits is high and in, the case of semiconductor structure, occupies significant chip area with respect to the operation performed. Since the mid 1990s a number of research groups, universities and companies have developed distributed circuits (amplifiers and oscillators) in silicon technologies, targeting cost and monolithic implementation. It is worth noting that these implementations are mostly of a proof-of-concept nature rather than being real products in an integrated form.
In the case of distributed amplifiers, several implementations have been proposed in the literature, with the most representatives ones being those of Yves Baeyens, Nils Weimann et al. "High gain-bandwidth differential distributed InP D-HBT driver amplifiers with large (11.3Vpp) output swing at 40 Gb/s", IEEE Journal of Solid-State Circuits, vol. 39, pp. 1697-1705, October 2004, and Hee-Tae Ann and Allstot "A 0.5-8.5 GHz fully differential CMOS distributed amplifier", IEEE Journal of Solid-State Circuits, vol. 37, pp. 985-993, August 2002. The former publication teaches a laser driver for 40 Gbits/sec optical communications using GaAs—InP HBTs (D-HBTs), while the latter describes a fully distributed differential amplifier with constant group delay in a bandwidth of 8.5 GHz with the use of 0.6 μm CMOS technology.
As far as distributed oscillators are concerned, there are minimal examples in the literature. The most representative ones include that described by H. Wu and A. Hajimiri, "Silicon-Based Distributed Voltage-Controlled Oscillators", IEEE J. Solid State Circ., 36 (2001) pp. 493-502. This analyses the design of a distributed oscillator with single-ended architecture in CMOS and BiCMOS technologies. Furthermore, a frequency tuning technique is presented and analyzed, known as "current steering" tuning. This mechanism is based on adjusting round trip delay to produce a corresponding frequency change. Specifically, two approaches to frequency tuning are presented: changing phase velocity in a loaded transmission line and changing the effective lengths of the transmission lines. The oscillation frequency is 12 GHz using BJT technology and 10 GHz using CMOS technology. This oscillator has a large coupling capacitance between the input terminals and output of the circuit.
In D. Guckenberger and K. T. Kornegay, "Design of a differential distributed amplifier and oscillator using close-packed interleaved transmission lines", IEEE J. Solid-State Circuits, vol. 40, pp. 1997-2007, October 2005, a differential distributed oscillator is described using 0.13 μm SiGe BiCMOS technology. This circuit has a connection between its input and output of the circuit using bond wires. The oscillation frequency is 9.2 GHz and the proposed frequency tuning technique is that of "current starvation" whereby the delay that an amplification cell contributes to the overall open-loop delay is changed. A disadvantage of this technique is that it gives rise to variations of the output power with respect to oscillator control voltage.
The use of a cross-coupled transistor pair in a differential amplifier to vary delay in a CMOS ring oscillator is known from B. Razavi "Design of Analog CMOS Integrated Circuits" McGraw-Hill, International Edition, 2001, pages 515 to 518.
The disclosure of each of the above references is specifically incorporated in this application by their citation. The present invention, according to a first aspect, provides an integrated circuit distributed radio frequency (RF) oscillator comprising a semiconductor chip which includes: first and second differential RF transmission lines; coupled in parallel between the first and second transmission lines at spaced-apart positions along the transmission lines, a plurality of differential amplifier cells with adjustable delay; an oscillation feedback link between the first and second transmission lines; and an output buffer connected to one of the first and second transmission lines.
The feedback link typically comprises a pair of metal-insulator-metal (MIM) capacitors forming part of the chip, the first and second differential transmission lines being arranged in series but, also, side-by-side and bent into a loop so that an input end of one of the transmission lines lies adjacent an output end of the other. The capacitors are located between these adjacent ends to interconnect the ends.
It will be understood that, typically, with the transmission lines forming loops, if they are formed in the same layer of the semiconductor chip and lie alongside each other, one transmission line has a longer physical length than the other. In this instance, the transmission lines are constructed such that they have different wave propagation velocities in order that their electrical lengths are substantially equal.
In the preferred oscillator, the series-connected first and second differential transmission lines form a spiral path having neighboring input and output portions arranged side-by-side with one portion inside the other, the amplifier cells being distributed around the spiral and each having a differential input connected to the input portion and a differential output connected to the output portion. In the example described hereinafter, the output portion is inside the input portion, but it is also possible for the reverse to apply. The amplifier cells are arranged such that they constitute substantially radially oriented signal paths which are angularly spaced apart around the spiral. Although the spiral may be curved, it is preferred that the input and output portions each form a respective rectilinear portion of the spiral, each such rectilinear portion having a plurality of sides, typically four sides, with the amplifier cells each being connected to a respective one of the sides of each rectilinear portion. Thus, each side of each rectilinear spiral portion may be at right angles to at least one consecutive side of that rectilinear portion and, with the intermediate sides of the rectilinear spiral portion being at right angles to consecutive sides at either end. Each rectilinear spiral portion side may then run alongside and parallel to a respective side of the other rectilinear spiral portion.
The differential transmission lines, the amplifier cells and the feedback link form an oscillator core with each of the amplifier cells having a differential input coupled to the first transmission line and a differential output coupled to the second transmission line. It is preferred that the output end of the first transmission line, in this case, forms an output of the oscillator core. Such an output may feed an on-chip output buffer having a differential input.
Different transmission line configurations may be used for the differential transmission lines, depending, particularly, on the frequency band in which the oscillator operates. In the preferred embodiment of the invention, each differential transmission line comprises a pair of parallel metal microstrip tracks in a single metal layer of the chip, or the metal layer beneath the substrate. The requirement for balanced variations between high values of odd mode impedances in the transmission lines and low losses at the operation frequency or frequencies affects the choice of structure for the transmission lines. Thus, the backplate may be omitted and the transmission line may be microstrip over substrate. Typically, the transmission line is capacitively loaded by a backplate close to the microstrip tracks in order to lower the propagation velocity and, thereby, to achieve the required phase shift along the transmission lines within a compact structure.
With regard to the capacitive feedback link, this may comprise at least one pair of capacitors, each pair comprising a first pair capacitor interconnecting a first track of one of the differential transmission lines and a first track of the other differential transmission line, and a second capacitor adjacent the first capacitor and interconnecting a second track of the one differential transmission line and a second track of the other differential transmission line. Preferably, the capacitor is isolated from the chip substrate.
The preferred oscillator is a voltage-controlled variable frequency oscillator. Frequency variation is produced by arranging for each of the amplifier cells to constitute a variable delay element, each having a control input for receiving a tuning signal, the delay of the amplifier cell being dependent on a parameter of the tuning signal, e.g. its voltage. It is preferred that each of the differential amplifier cells has a differential control input and a positive feedback circuit for varying the delay. The positive feedback circuit applies a negative resistance load to the amplifier output and, depending on the level of positive feedback, the delay is varied. It is possible to achieve delay variation by apportioning a fixed total d.c. supply current variably between the differential amplifier circuit and a cross-coupled transistor pair as a positive feedback circuit of the amplifier cell, variation in the apportionment being in response to variation of a differential control voltage input. In the preferred embodiment, all of the amplifier cells of the oscillator core are tuned in unison by a single differential voltage control signal.
In order to maintain synchronization of the signals propagating along the differential transmission lines, the d.c. supply current for the differential amplifier circuit of each amplifier cell may consist of a fixed part and a variable part, the fixed part being several times bigger than the sum of the variable supply currents for the differential amplifier circuit and the cross-coupled pair.
The semiconductor chip preferably uses bipolar transistors, e.g. formed using SiGe BiCMOS technology. This technology combines high performance hetero junction bipolar transistors (HBTs) with CMOS digital circuitry. As an alternative, MOSFET transistors using CMOS technology may be used.
Other aspects of the invention, including a method for designing an integrated circuit distributed oscillator, are set out in the claims.
The invention will now be described by way of example with reference to the drawings in which:—
Referring to
The differential base line has an input end 14I and an output end 14O. Likewise, the differential collector line 16 has an input end 16I and an output end 16O. The spacing between each amplifier cell input connection to the differential base line 14 is lb along the line 14, with the outermost cells 18-1, 18-4 each being connected to the differential base line 14 at a distance lb/2 from the input end 14I and the output end 14O respectively. Similarly, the separation distances between the connections of the outputs of the amplifier cells to the differential collector line 16 are lc, along the line 16, with the output connections of the outermost amplifier cells 18-1, 18-4 being at a distance lc/2 from the input and output ends 16I, 16O respectively. In practice, although the physical lengths lb and lc are different; their electrical lengths are equal, as will be described below.
It will be understood that a differential RF signal at the input end 14I of the differential baseline 14 propagates along the line at a velocity dependent on the characteristics of the line. At each tapping point represented by the connection of the differential input of an amplifier cell 18-1, 18-2, 18-3, 18-4 to the baseline 14, the signal is amplified by the respective amplifier cell and a corresponding output is fed to a respective feed point on the differential collector line 16, the amplified signal then being propagated along the collector line. Each amplifier cell introduces a small delay between its input and its output. The spacing of the cells along the differential base and collector lines is such that, at a required frequency of operation, the output signal of each amplifier cell reinforces the other output signals traveling along the differential collector line 16 from the other amplifier cells. In other words, at the frequency of operation the signals in each transmission line are synchronized. Each line 14, 16, is terminated at a predetermined distance from the amplifier connection nearest the respective end in order that a signal at the amplifier connection is reflected back to that connection with a phase that reinforces the incident signal, i.e. by arranging for the separation of the outermost amplifier cell connections from the respective transmission line ends to be half the separation between consecutive amplifier cell connections on the line.
Each differential transmission line 14, 16 is terminated at one of its ends by a differential pair of resistances Zb, Zc respectively, each termination also serving to bias the transistors of the amplifier cells 18-1 to 18-4 by their connection to respective voltage sources VBB, VCC.
Thus far, the structure described is that of a differential distributed amplifier. In order for the circuit to operate as an oscillator, the differential feedback loop 20 interconnects the output end 16O of the differential collector line 16 to the input end 14I of the differential base line. Incorporated in the feedback line 20 is a pair of two coupling capacitances 22A, 22B, each connected in series in the respective differential conductor 20A, 20B of the feedback line 20. For diagrammatic simplicity, the feedback line 20 is shown in
The feedback link provides positive feedback, leading to oscillation at a frequency at which the signals along the differential transmission lines 14, 16 are synchronized in the manner described above.
The output from the oscillator core is produced at the output end 14O of the differential baseline 14 which is connected to the input of a high-speed differential output buffer 24 which, in turn, has a buffered differential output 26 coupled to output pins (not shown in
The capacitors 22A, 22B are MIM capacitors formed on the chip. These are, in relation to the frequency of operation, large AC capacitors, isolated from the substrate and each having a value in the region of 0.7 to 1.0 pF.
The output buffer provides a standard 50 ohm output impedance, and input characteristic impedance equal to the odd-mode impedance of the differential baseline 14 being other than 50 ohms. The output buffer 24 isolates the main oscillator core 10 from succeeding stages of the equipment to which the integrated circuit is connected or from succeeding stages following the output buffer within the integrated circuit (in the case that such stages are embodied in the chip). It is also possible to adjust the output amplitude of the oscillator by adjusting the gain of the output buffer 24 using a gain control input 28.
The frequency of oscillation of the distributed oscillator depends on the round-trip delay produced by the differential transmission lines 14, 16, the amplifier cells 18-1 to 18-4 and the feedback link 20. It follows that the frequency of the oscillator 20 can be tuned by altering the delay component introduced by the amplifier cells, each of which has a differential control input connected to a differential tuning input 30 on two pins of the integrated circuit, the connection being made by control lines 32A, 32B running between each amplifier cell and the tuning input 30. The manner in which the delay of the amplifier cells is varied will be described below.
As explained above, the positioning of the oscillator components in the diagram of
It will be understood that this looped spiral configuration of the differential transmission lines 14, 16 allows the output end of the differential collector line 16 to lie immediately adjacent the input end 14I of the differential baseline 14 in order that they can be directly interconnected by the capacitors 22A, 22B without intermediate lines. Since the two transmission lines 14, 16 lie respectively one inside the other, their physical lengths are different. However, their electrical lengths are substantially identical. For this reason, the tracks of the respective lines 14, 16 are differently dimensioned. In this example, the characteristic impedance of the differential collector line 16 is approximately 10 ohms lower than that of the differential baseline 14. The lines are low loss lines in order to achieve high oscillation amplitudes and, as stated above, are formed as differential microstrip transmission lines with the backplate of the chip forming a ground reference. Losses are controllable via the spacing of the signal lines. Low odd-mode characteristic impedances are exhibited by the transmission lines owing to a short vertical distance between comparatively wide signal lines and the backplate (approximately 2.5 μm). It will be noted that consecutive sides of the rectilinear portions of the spiral are at 90° to each other. The transmission line bending does not substantially affect wave propagation since the dimensions of the discontinuities that they represent are negligible compared to the operating wavelength on the chip. One result of the spiral routing of the transmission lines is that their inner and outer tracks are imbalanced. This imbalance is compensated by 90° bending of the inner tracks at each corner between the rectilinear sides and a dual 45° bending of the outer tracks at the corners.
With regard to the terminating resistors Zc at the input end 16I of the differential collector line 16 (which are in the reverse direction with respect to signal flow in the line 16), emphasis is put on their connection with the power supply.
The first metal layer of the chip is used for minimizing the coupling capacitance between this metal layer and the differential transmission line.
On the basis that a central region 40 of the spiral can be identified, the four amplifier cells 18-1-18-4 represent substantially radially oriented signal paths extending between the input and output portions (the differential base line 14 and the differential collector line 16) of the spiral path. They are uniformly spaced along the lines 14, 16 and, therefore, angularly spaced apart around the spiral path. Each cell is located at an intermediate position along a respective side of the four-sided rectilinear portion of the spiral path. The first and the last amplifier cells 18-1, 18-4 are connected to the base transmission line 14 at a distance of lb/2 along the line from, respectively, adjacent end 14I and the output end 14O where it is connected to the output buffer 24. The separation between each amplifier cell and the adjacent corners of the differential baseline 14 is the same distance, lb/2 in each case, as shown in
In order to minimize unwanted coupling and interference, connections 42 to the amplifier cells 18-1-18-4 are also oriented radially with respect to the spiral central region. In particular, they are oriented perpendicularly to the respective sides of the spiraled transmission lines 14, 16, running outwardly away from the spiral path. This applies particularly to the control lines 32A, 32B (see
Frequency tuning of the oscillator is performed by varying the overall delay of the equivalent open-loop circuit, which in turn leads to a change of the oscillation frequency. In the preferred embodiment of the invention, this variation is achieved using delay variation by positive feedback. More particularly, in the preferred oscillator the overall delay is adjusted by changing the delay that the amplifier cells 18-1-18-4 contribute.
Referring to
It will be seen that the tail current of the differential amplifier long-tailed pair Q1, Q2 is the sum of the fixed current IBIAS of a first constant current source and a variable component of the fixed current ITUNE of a second constant current source. The remainder of the current ITUNE is drawn by the cross-coupled pair Q3, Q4, the sharing of the current ITUNE of the second constant current source being controlled by a differential pair of transistors Q5, Q6 having their emitter connections linked together and to the second constant current source, and their base connections forming a differential control input 44. This control input 44 of each amplifier cell is coupled to a common differential tuning input 30 of the oscillator (
Regarding the ratio between the tail currents ITUNE and IBIAS of the constant current sources, it should be noted that a large ratio value IBIAS/ITUNE results in a wide tuning frequency range, but care is needed to avoid a significant deviation of the differential amplifier operating point. Such deviation can result in line synchronization errors that can lead to imperfect superposition of the propagating waves on the differential collector line or to deviations with respect to the odd mode characteristics of the loaded differential collector line. Such effects lead, in turn, to an increase in phase noise due to impedance mismatching between the terminating resistors and the transmission lines, and may cause lack of oscillation. For this reason, the ratio IBIAS/ITUNE is chosen so that it allows tolerable line synchronization errors. Line synchronization is also affected by the length of the emitters of the cross-coupled transistor pair Q3, Q4. These lengths are kept small, the ratio of the emitter lengths of the differential amplifier transistor pair Q1, Q2 with respect to those of the cross-coupled pair Q3, Q4 being at least 5:1, and typically in the region of 7.5:1. In the specific implementation of the oscillator (in 0.35 μm SiGe BiCMOS technology) the emitter lengths are given by: Le1,2/Le3,4=6 μm/0.8 μm and the biasing and tuning currents are given by IBIAS/ITUNE=2.3 mA/0.3 mA, i.e. also with a ratio in the region of 7.5:1.
Depriving a differential amplifier long-tailed pair of current to alter the delay of the amplifier, a technique known as current starvation, has, in the past, resulted in a large output power deviation across the operating frequency range. This is due to the fact that the tail current of a long-tailed pair differential amplifier varies the control voltage having as a consequence, that the differential voltage swing is not constant. The positive feedback technique, applied to each of the amplifier cells 18-1-18-4 (
Referring to
The resistors used at the collectors of the differential amplifiers of the oscillator should be selected in such a way that the output buffer amplifies and limits the signal amplitude.
The current sources 46 of the buffer differential amplifiers are implemented with HBT transistors and a polysilicon resistor (not shown) connected between emitter and ground in each case. The base voltage of this HBT transistor may be controlled by an adjustable voltage reference circuit structure via the buffer control input 28 (
The complete layout of the preferred integrated circuit oscillator in accordance with the inventive is shown in
The design of the integrated differential distributed VCO requires the consideration of a number of physical constraints that layout restrictions, full integration into the same silicon device, and the electromagnetic behavior of the interconnections and the transmission lines, impose. These restrictions are associated with the corresponding circuit parameters to specify the range of their possible values and, indeed, to define them accurately. If these are not taken into account at the circuit design level of the oscillator, it is possible that a non-feasible solution is reached. To determine appropriate values in required implementations, an analytical design methodology may be used. This methodology is described below for an implementation based on BJTs, but the process is similar for implementations based on MOSFETs. More specifically, the parameters that need to be taken into consideration are the following:
The values of the preceding parameters are limited by the design rules of the specific technology employed, as well as by its electrical performance in the worst case. For example, regarding the physical parameters, the conductor widths and spacings Wc, Wb, Sc, Sb of the transmission lines 14, 16, their minimum values are defined by the specific technology used for the oscillator implementation and their maximum values are calculated by taking into consideration the lowest value of the odd mode characteristic impedance that the "unloaded" transmission lines can have (e.g. 50 ohms). The methodology that is followed for a specified set of design parameters is now described with reference to in
Referring to
This procedure is performed by the designer for a specific current ratio IBIAS/ITUNE. If, after the harmonic balance step, no oscillation is achieved in the desired frequency range, the ratio is increased according to the considerations presented above in the description of the amplifier cell, and the whole procedure is repeated until a valid solution is reached.
In conclusion, the integrated differential distributed oscillator differentiates and exhibits certain advantages over the existing relevant distributed designs and implementations in the following points:
The center oscillation frequency of the preferred integrated circuit oscillator is 14.25 GHz, as shown in
Referring to
The tuning range of the oscillation frequency of the preferred oscillator using the amplifier cell delay variation described above is 420 MHz, with the oscillation frequency ranging between 13.95 GHz-14.37 GHz, (i.e. in the region of three percent of the center frequency) as shown in
The circuit has been designed in such a way that the feedback loop closes with the use of on-chip MIM capacitors, allowing for reduction of the oscillator pins as well as for reduced coupling noise with off-chip elements. It employs a frequency tuning technique which ensures linear frequency variation and constant output voltage with respect to the differential control voltage, a fact which allows for a significant degree of isolation of the oscillator from external interference, and achieves higher operation frequency as well as lower noise levels compared with lumped oscillator circuits implemented in the same silicon technology processes. This oscillator is used in complex integrated circuits for communication applications.
The invention has particular application in the areas of high speed communication, such as optical communications and microwave links where the use of oscillators operating at very high frequencies is required. Indicatively, such an oscillator may be used in a PLL (Phase Locked Loop) e.g. forming part of a Serializer/Deserializer device for optical communication applications with 10 GHz line rate.
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Syracuse guard Michael Carter-Williams is a stud. The 6'6" sophomore is projected to go 11th in NBADraft.Net's latest mock draft, and he gave us a pretty idea of why in No. 3 Syracuse's 57-55 victory over No. 21 Cincinnati on Monday. Carter-Williams had 16 points, seven assists, and five rebounds in the win. Two of his points came in fancy fashion on this spectacular dunk: Oh, and
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How to: Experience Fort Worth's Two Sides in Two Days
November 21st 2014
By Karen Gardiner Dion
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The BeetlePaperback Tales of Mystery & the Supernatural
Free delivery worldwide
Dispatched in 1 business day
When will my order arrive?
Additional formats available
- Format
- Hardback $25.16
- Publisher: Wordsworth Editions Ltd
- Format: Paperback | 288 pages
- Dimensions: 124mm x 196mm x 20mm | 159g
- Publication date: 5 March 2007
- Publication City/Country: Herts
- Sales rank: 70,524
Product description
I saw him take a different shape before my eyes. His loose draperies fell about him...and there issued out of them a monstrous creature of the beetle tribe...' From out of the dark and mystic Egypt comes The Beetle, a creature of horror, 'born of neither God nor man', which can change its form at will. It is bent on revenge for a crime committed against the devotees of an ancient religion. At large in London, it pursues its victims without mercy and no one, it seems, is safe from its gruesome clutches. Richard Marsh's weird, compelling and highly original novel, which once outsold Dracula, is both a horror masterpiece and a fin de siecle melodrama embracing the fears and concerns of late Victorian society. Long out of print, The Beetle is now available in this Wordsworth edition, ready to chill you to the marrow and give you nightmares.
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Jimmy Toscano
2mComments (1)The Patriots' defense saves the day, as a last-minute Vince Wilfork interception bails out the punchless offense in a 16-9 victory over the winless Raiders.
2mComments (2)Steven Wright's career was stalled when he took up the knuckleball in 2010. Now he's with the Red Sox and it's taking off.
2mStevan Ridley rushes for 101 yards and a touchdown on Sunday, his sixth career 100-yard game.
2mJulian Edelman catches 6 passes for 80 yards and a touchdown on Sunday while the rest of Tom Brady's wideouts are ignored.
2mComments (3)Tom Brady's glum demeanor makes it clear: He didn't think the offense pulled its weight in the Patriots' 30-7 victory.
2mThe Patriots turn in their finest defensive effort in many a day as they rout the Vikings, 30-7, for their first victory of 2014.
2mMookie Betts will get playing time at second base again, the position he played up until this season.


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Welcome To GMTruckClub.com!
The #1 Chevy Truck Forum Online
Online since 2004, we're the #1 Chevy Truck & SUV user community. If you have any questions about your Chevy or GMC Truck, SUV or Crossover, or just want to connect with other GM owners and enthusiasts around the world, you've found the best place on the internet to do that.
Join Today ~ It's Free
Registering is Free and Easy! Do it today and we'll see you on the forums soon!
Labor Day Sales & Coupon Codes - Good time to get stuff for your truck
Discussion in 'General Classifieds' started by ChevyFan, Sep 1, 2011.


text:
Celebs seen at hot spots all over town
They're going out
Former WWE star Bill Goldberg had dinner with his mother and siblings Friday night at Town Kitchen and Bar in South Miami. Former New York Yankee great turned Los Angeles Dodgers manager Don Mattingly had lunch Wednesday with former Yankees bat boy Shawn DeRosa at Perricone's Marketplace & Cafe before his team took the field with the Miami Marlins. Newly signed Miami Heat center Greg Oden dined with New York Times best-selling author Ian Halperin (Unmasked: The Final Years of Michael Jackson) and two women Saturday night at Catch Miami. After dinner, they went to SL Miami for drinks. On Friday night, Erik Spoelstra was seen eating dinner there with and his girlfriend and two friends.
On Our Radar
On Our Radar
- Gloria Estefan to lead Q&A
- CSI Miami star Omar Miller talks Weekend Fix
- Dwyane Wade getting ready for A Night on the Runwade
- Mr. Olympia Phil Heath gives diet and exercise tips before the holidays
- Pharrell can't sell his Miami condo
- Supermodel Elle Macpherson at opening of Stripsteak
- Eric Trump marries in Palm Beach
- Miami actor Carlos Ponce stays busy
- Jersey Belle star Jaime Sullivan in Miami
- Shireen Sandoval named 'Deco Drive' cohost


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Originally written on Pro Sports Daily | Last updated 11/19/14
NEW YORK -- Carmelo Anthony already had been ejected with his second technical foul about midway through the fourth quarter when the Knicks star forward prepared to walk toward a hallway outside the team's locker room. That's when he saw his coach, Mike Woodson, making his own exit from the court. The pair would soon be joined by center Tyson Chandler, who was ejected along with Chicago Bulls center Joakim Noah for "fighting" in the waning moments of Chicago's 110-106 win at Madison Square Garden on Friday night. "I walked in the hallway and Woody was walking back," Anthony said of his coach. Soon after, Anthony exited the shower and saw Chandler. "Once I saw that," Anthony added with a smile, "I knew that's how the night was going." It did not go well for the Knicks (19-6), who dropped their second game in their last three at the Garden, where they had started the season 10-0. Chicago (15-10) dominated throughout and w...
Original Story: http://www.prosportsdaily.com/article...
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LX-UCV taxing to Rwy 27R for departure to LAX as CLX751.
CV789 returning from an air-test, credits to Andre Giam for the edit!
Painted in the new colours and returning from an air-test as CV789.
'City of Differdange', the first Cargolux -400 freighter to carry the new livery returning from a 3 hour air-test as CV789.
Taxiing for departure off 07 Right.
Holding short of 15L while an Atlas 747 lands on 15R


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Founded in 1997, the mission of the Evanston Dance Ensemble is to deepen the exposure to, and appreciation of, dance for highly talented and committed young performers and diverse audiences in the greater Chicago area.
In residence at Dance Center Evanston, the Ensemble performs several productions each year. EDE is known for its inventive treatment of stories and themes and collaborating with top professionals in the field to create original productions.
The Ensemble also extends its involvement into the community with its second company, ede2, which tours its own original shows to schools, libraries, and senior centers throughout the North Shore.
Béa Rashid, Artistic Director and Founder
Christina Ernst, Artistic Director
Allison Kurtz Volkers, ede2 Director
Upcoming Events
The Lion, the Witch and the Wardrobe
December 5-7, preview December 4
Tickets through the Louis Theater box office
At the Barber Theater – 30 Arts Circle Drive
By phone: 847.491.7282
Online right here
ede2 dances with the Evanston Symphony Orchestra
December 7 at 3:00 pm
Evanston Township High School


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|Fishing from Kayaks and Canoes
|New Topic
|Printer Friendly Version
Hey plbytx
Posted by: pirateoverforty on Feb-09-11 4:26 PM (EST)
I store my boats outside in 100+ and haven't had a problem. You do have to keep them out of the sun. If your garage is not air conditioned it's probably hotter in there than ouside. I built a storage rack out of PVC pipe. You can also store it upside down instead of on it's side.
Paddler's Truck Rack
Free Standing Boat Racks
2-3 Canoe/Kayak Trailer
EZ-Dock modular docks
Dry Tops
|Table of Contents


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Is your resume in need of a little disruption?
Startups are all about
making things work better.
Our resume writing service is all about doing that for your CV.
StartUpHire is the place to find Principal-Security-Engineer jobs in and near . Review the list below of Principal-Security-Engineer jobs. These Principal-Security-Engineer jobs represent some of the most rewarding careers available. You can refine your job search for Principal-Security-Engineer jobs in by adding a job title, company name, or keyword to the search box above … or click the "Advanced Search" link for more options. Don't see the employment opportunity you're looking for? Check back soon for more Principal-Security-Engineer jobs in , or sign up for an email alert (link in upper left) to receive periodic updates on new Principal-Security-Engineer jobs in , .
The Principal Systems Engineer provides high-level support of the corporate and production LAN/WAN infrastructure. In addition, the Principal Systems Engineer manages and monitors the security of the PHT Corporate Infrastructure. Position Responsibilities:10/1/2014 Boston, MA Save This Job
Description Worldwide Leader in state-of-the-art Enterprise Software Platform development, Good Technology delivers first-in-class mobile productivity solutions with the highest security certification across iOS, Android and Windows mobile devices. We lead the industry in secure10/22/2014 Sunnyvale, CA Save This Job
Job Number:14-01-4665149SF Job Title:Principal Consultant ?Cyber Security Engineer - NERC Compliance Posting Date:08/08/14 Location:San Francisco, CA Business Unit:Utility Services Relocation Offered?:No Nexant, founded on January 1, 2000, is an independent provider of9/29/2014 San Francisco, CA Save This Job
Vormetric is making the world a better place by enabling organizations around the world ? including 17 of the Fortune 25 ? to both reduce their risk and lower their costs as they protect what matters: their sensitive data. The threats to our customers? valuable data are ever9/29/2014 San Jose, CA Save This Job
Company Overview Ruckus Wireless is a pioneer in the wireless infrastructure market, enabling carriers and enterprises to stay ahead of the exploding demand for high-bandwidth applications and services. The Ruckus Smart Wi-Fi technology redefines what?s possible in wireless11/12/2014 Sunnyvale, CA Save This Job
More information about this job Overview DataDirect Networks (DDN), with a global employee base of 450+, is the world?s largest, privately-held, data storage infrastructure provider. DDN maximizes the value of all information everywhere. They make the challenge of providing10/21/2014 Chatsworth, CA Save This Job
Ruckus Wireless RKUS, a Wi-Fi industry leader in technical innovation, revenue growth, and market share, is seeking a network security expert to fill a key position as a member of the technical staff. Reporting to the Director of System Architecture, the successful candidate will10/13/2014 Sunnyvale, CA Save This Job
OPPORTUNITY OVERVIEW We are looking for a seasoned engineer who can design highly complex scalable products, crank up quality code, and ensure customer experience as one of the main pillars of development. This role will require being a heavy influencer in the organization,9/29/2014 San Jose, CA Save This Job
Overview: Aerohive Networks?the pioneer in controller-less Wi-Fi?reduces the cost and complexity of today's networks with cloud-enabled Wi-Fi and routing solutions for medium and large enterprise headquarters, branch offices and teleworkers. Aerohive?s award-winning cooperative10/4/2014 Sunnyvale, CA Save This Job
The Principal or Senior SQA Engineer will help advance Security Innovation?s security library and related software for connected-vehicle applications. This work is being driven by the U.S. Department of Transportation, the European Telecommunications Standards Institute (ETSI),10/5/2014 Boston, MA Save This Job
We're looking for a Big Data Principal Engineer that is equally comfortable diving into the nuts and bolts of building a "big data" server application as well as applying computer and network security expertise to shape and drive the pro10/28/2014 Waltham, MA Save This Job
Type: Full Time Virsec is looking for a software engineer with strong background in C/C++. Do you see yourself in a role that will help reshape the world of cyber security? We?re building the future of cyber security, and we?re looking for talented, problem solvers to join11/24/2014 Acton, MA Save This Job
About Apigee, the Platform for Digital Business By 2016, 85% of enterprises will adopt APIs. By 2025, more than 25 trillion connected devices will be communicating with smart phones and each other. This isn?t your grandfather?s enterprise software company! We are an11/17/2014 San Jose, CA Save This Job
Nominum?s software provides Internet access and applications for the largest, most diverse Internet service providers around the world, providing products that range from internet connectivity to providing innovative security solutions and messaging that reaches more than 50011/14/2014 Redwood City, CA Save This Job
PRINCIPAL PURPOSE OF JOB: The Capacity Planning Engineer for infrastructure, works closely with other architects, production support engineers, development leads, customer experience teams, and LOB staff to develop and maintain the technical direction of the iHealth Technologies11/19/2014 Atlanta, GA Save This Job
Company Overview Ruckus Wireless is a pioneer in the wireless infrastructure market, enabling carriers and enterprises to stay ahead of the exploding demand for high-bandwidth applications and services. The Ruckus Smart Wi-Fi technology redefines what?s possible in wireless11/12/2014 Sunnyvale, CA Save This Job
Description With over 1.9 million active enterprise users, Good Technology delivers the only mobile business-class productivity solution with the highest security certification across iOS and Android. The leader in secure enterprise mobility solutions, the Good Collaboration10/22/2014 Sunnyvale, CA Save This Job
About Apigee, the Platform for Digital Business Apigee?s market is comprised of businesses undergoing digital transformation in response to the sudden dominance of mobile end-user computing and related new forms of competition. This is a new style of computing. It cannot be10/18/2014 New York, NY Save This Job
Description With over 1.9 million enterprise users, and half the FORTUNE 100? as our clients, Good Technology is the Worldwide Leader in state-of-the-art Enterprise Mobile Application and Mobile Software Platform development. Here at Good Technology we deliver first-in-class10/22/2014 Sunnyvale, CA Save This Job
Description With over 1.9 million enterprise users, and half the FORTUNE 100? as clients, Good Technology is the worldwide leader in Enterprise Mobile Application and Mobile Software Platform development. At Good Technology we deliver first-in-class mobile productivity10/22/2014 Sunnyvale, CA Save This Job


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The Cast
Past Shows
Contact Us
Friday, December 5,2014 dinner at 6:00 PM
Saturday, December 6,2014 dinner at 6:00 PM
Admission is $25.00 per person
Includes dinner, adult beverages and holiday entertainment
Happy Holidays!
Deadline for reservations and payment is 11/25/14.
To reserve your party of family and friends, contact Carol at 722-5716. OR
Advance Tickets Available At
St. John School Office 607-723-0703
9 Livingston Street
Binghamton, NY 13903
St. John & Andrew Church Hall Handicap Accessible
1263 Vestal Ave
Binghamton, NY 13903
For more information, call 607-723-0703
St. John The Evangelist School Benefit
web site counter


text:
Akumal Villa Rental Photos and Description
Villa, 3 Bedrooms + Convertible bed(s), 3 Baths (Sleeps 10-12)
This 3 bedroom, 3 bath luxury individual villa overlooking the sandy beach section of Half Moon Bay and the Caribbean beyond is the larger of 3 other villas sharing a cenote style pool with cascade. The villa can sleep 10 people comfortably. It has 2 king beds, one queen, and 3 double beds, full kitchen and fantastic beachfront and pool view..
Specially designed for select people who appreciate privacy and the comforts of home in paradise. The villa is unique in design and decor, with high domes and arches in a Moorish Mediterranean style architecture. It has an exquisite views of the pool deck and beach. Lounge beds and hammocks provide comfort and shade for relaxation or sunbathing. The villa has its own private terrace and outdoor grill surrounded by a lush tropical garden and coconut palms.
Villas Flamingo are for those who prefer a lifestyle other than a crowded condominium or hotel. A getaway place to pamper yourself in your own luxury villa. A new approach to enjoy life on the Mexican Caribbean.......
- Suitability:
- Long-term Renters Welcome
- Low Allergen Environment
- Minimum Age Limit for Renters
- children welcome
- pets not allowed
- smoking allowed
- wheelchair inaccessible
About Paula or Leon
I am an ecologist and love nature! Animals! Travelling the world. I am a PADI DIVE MASTER. I dedicate my diving to hunting the lion fish, an invasive species in the Caribbean. I eat delicious fresh lion fish everyday at my daughter's restaurant across from my villas. Born in Mexico DF, but always lived in Cozumel, Playa del Carmen, and Akumal. I practice yoga and have deep respect for our amazing blue planet.
Why Paula or Leon chose Akumal
I built these villas years ago and have been remodelling as needed along the way. The Moorish Mediterranean architecture was inspired from my many journeys overseas. We recycle everything and I have labeled bins for glass, aluminum, paper and plastics, and organics in all my kitchens in all my properties. Raised in Akumal, I could never leave it, except to travel. Its a real paradise.
What makes this villa unique
Scuba diving! And my Father founded Akumal.


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Interstate 95
Bus Driver May Have Had Medical Incident Before I-95 Crash
The driver of a tour bus that ran off a highway north of Boston Tuesday night may have had a medical episode just before the crash.
Dump Truck Crashes Into Overpass On Route 128 In Canton
A dump truck crash brought the start of rush hour to a crawl on Route 128 in Canton early Thursday morning.
Sheriff's Deputy Killed In Motorcycle Crash On I-95 In Sharon
A sheriff's deputy was killed in a motorcycle crash on Interstate 95 during rush hour Tuesday morning.
Tour Bus, 2 Cars Crash On I-95 In Canton
The northbound side of Interstate 95 was shut down briefly early Thursday afternoon after a tour bus and two cars crashed.
Crash Shuts Down Route 128 In Westwood
Both sides of Route 128 were shut down late Tuesday morning after an accident in Westwood.
1 Dead In Crash On I-95 In Attleboro
A person was killed in a crash on Interstate 95 in Attleboro early Wednesday morning.
Driver Dies After Rolling Onto Guardrail On I-95 In Attleboro
A driver from Mattapan was killed in an early morning crash on Interstate 95 in Attleboro Monday.
Truck Rolls Over On I-95 Ramp In Attleboro
A tractor trailer rolled over on the ramp from I-95 southbound at I-295 in Attleboro on Monday.
Stop Sticks Bring I-95 Police Chase To An End
Police used stop sticks to pull over a woman driving a Toyota Corolla with no license plates on I-95 in Newbury on Thursday morning.
Ink Spilled In Peabody Crash Turns Water Green
PEABODY (CBS) – Ink spilled in a messy crash on Wednesday is turning water in Peabody bright green. In the crash, a big rig hauling printer cartridges tipped over on a ramp to I95. The […]


text:
What Houzzers are commenting on:
Rack It Up Bamboo Shelf Pot Rack
You have to get creative when facing a small space and the Enclume Rack It Up Bar & Bamboo Shelf Pot Rack helps you make the most of your room without sacrificing elegant style. This handy bar and shelf utilizes your wall space keeping pans and utensils out of your cabinets and off your countertops to free up space for other items. Made of thick high-capacity steel the bar has a durable simulated hammered steel powder-coated finish. On top of the bar you'll find a convenient shelf made of modern eco-friendly attractive bamboo. This shelf is perfect for holding spices knick-knacks or even your keys and wallet. Eight pot hooks are included for your convenience. In minutes this practical bar easily installs on drywall with super-strong new technology anchors eliminating the need to search for joists or studs.Pot racks free up countertop and cabinet space to keep your kitchen clutter-free and organized. Enclume's new Rack It Up! pot racks are designed for the smaller kitchens of the average middle-America home or apartment and are a cost-effective way to upgrade or organize your space. In minutes these practical pot racks easily install on drywall with super-strong new technology anchors eliminating the need to search for joists or studs. Perfect for your first pot rack these affordable and compact pieces feature the esteemed Enclume name and are superior in quality to other similarly priced brands.About Enclume Design Products Inc.Enclume Design Products Inc. is an esteemed manufacturer of cookware storage racks with products that set the industry standards for quality design function and strength. Fine "pot racks" have been the company's specialty since its founding in 1973 as a metal crafting company. Based in Port Hadlock Washington Enclume applies time-honored methods that have been used by master craftsmen for centuries. Their durable and practical ironwork products add style grace and organization to your kitchen hearth and home. Enclume has expanded its product line to include kitchen furniture hearth products finishing touches and accessories all made with the same care and innovation as their legendary pot racks.
Product Specifications
- Sold By
- Hayneedle
- Category
- Pot Racks
- Style
- Contemporary


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Writestream Tuesday with Teri OBrien
in Writing
Join author, blogger, writer and internet radio host Dariaanne for Writesream Tuesday on September 24 at 1 p.m. Eastern when she'll welcome author and talk radio host Teri O'Brien to the program.
Among other things, the host will talk with Teri about her new book The ABC's of Barack Obama: Understanding God's Greatest Gift to America, her talk radio show, the world of publishing, the current state of pop culture and the latest political happenings.
As always, your calls are welcome at (347) 945-7246. Tune in on September 24 at 1 p.m. Eastern for Writestream Tuesday with guest Teri O'Brien!
Previews of a Season: The 2014 Film Awards Season About to Begin!
in Film
A special Saturday night episode! Join Jason tonight as he previews the start of the 2014 Film Awards Season, which begins December 1, and the plan for coverage on Oscar, Oscar! Also, all the latest movie and Oscar news and updates before everything gets underway. Also, this month marks the 8th anniversary of the show on BlogTalkRadio, so join in tonight for a few remembrances and maybe a classic moment or two replayed from the first eight years of the show.
The 3 AMovIeGOerS Go Interstellar: Nov 2014
in Film
With Christopher Nolan's much anticipated film Interstellar now playing in theaters, Jason, Garney, and Jamey will not only provide their reviews, but then also reveal their Top 10 choices for the greatest science fiction movies ever made ... and see if Nolan's latest film belongs in that pantheon.
The Top 10 Film Trailers of 2014
in Film
It's time for the first recap countdown of 2014! As most of the film trailers are out for the movies of 2014, tonight, Jason provides his look back with his choices for the top 10 trailers of the year. Film trailers are an art in and of themselves, so tonight, hear Jason's best, and debate the choices.
A Book and a Chat with Dan Obrien
in Books
Dan is an editor, writer, and screenwriter. He currently attend a California university where he is pursuing a graduate degree in psychology. Dan has written over 10 novels, several screenplays, and is working on a graphic novel. A philosopher and martial artist, his days are filled with writing and training.
He will be along to chat about his works which inlcude The End of the World Playlist, Bitten, Cerulean Dreams, and The Journey as well as Emprical where he is the editor
Latest News & Updates
in Film
Join Jason to catch up on the latest film and Oscar news, as we get ever closer to the start of another Film Awards Season!
June OBrien Author of The North Road
in Spirituality
Author, poet, dream interpreter, psychotheapist and mother June O'Brien has done it again. In the second book of her trilogy, "The Blue Child Series" she has knocked it out of the park with "The North Road." The series is about three mature Native American sisters who have adventures in time and space and the mystical realms which will keep you on the edge of your seat. "The North Road" is a comtemporary version of the age-old battle between dark and light, and this book is hard to put down. I cannot wait to read the third one, which is as yet unwritten.
A native Oklahoman, June lives near Seattle and is a member of the Nansemond tribe.
If you liked Lynn Andrews books, you will love June O'Brien's. June tells her stories with the voice of authenticity, as she is a Native American herself.
Available on Amazon and Kindle.
Website: The Blue Child Series
Latest News & Updates
in Film
The fall movie season is well underway, and it's getting closer to yet another Film Awards Season! Join in tonight for all the latest film and Oscar news, and some personal film updates from Jason as well!
Is Sgt. Bergdahl a Hero or a Deserter? Plus,Jay Carney's Successor and His Role
Another day, another lawless act by the Obama regime, this time the release of five Gitmo detainees in exchange for Army Sgt. Bowe Bergdahl, who has been held in Afghanistan since June 30, 2009. Was Sgt. Bergdahl actually captured, or, as some strong evidence suggests, did he willingly walk away from duty? Does that matter? Does it matter that, once again, Barack Obama violated a duly-enacted Congressional statute, which requires that he give 30 days notice to Congress prior to transferring prisoners from Gitmo. The One acknowledges that he broke the law, but says it doesn't matter because he issued a signing statement when he signed the law last year, declaring the notification unconstitutional. And he should know, of course, as a "former Constitutional law professor," right? Ok, he was an adjunct lecturer who only got into law school owing to affirmative action, but that aside, where are the screams and gnashing of teeth from those who were so outraged over Pres. George W. Bush's use of signing statements? I can't help but notice that while W asserted that he would ignore aspects of Congressional enactments to protect the American public from terrorism, B.Hussein does so to release 5 detainees deemed "high risk" in "08 to obtain the release of a guy who, three days before going missing stated in an email to his parents ""I am ashamed to be an American. And the title of US soldier is just the lie of fools," he concluded. "I am sorry for everything. The horror that is America is disgusting." I guess reading that last sentence you can see why Barack Obama has a soft spot in his heart for this guy. Jay Carney's had enough of being a paid liar for the Regime. What did Jay's successor, Josh Earnest have to do with the Benghazi coverup?
Digital Resister (September 15th)
in Politics
Digital Resister: (September 15)
Steve OBrien looks at the Ross Ulbricht case, what do we know and what is still un discovered in the Silk Road case. We look at the deep web, what is it and talk about Tor, one of the most popular networks inside the net. Ross Ulbricht needs your help, please visit freeross.org.
Brought to you by FBGlive
Our thanks to the liberty beat for current news and information.
Digital Resister
in Lifestyle
Tonight on Digital Resister:
Host Steve OBrien Talks with Lokie of We Resisters Radio about his endevors and his new show starting Wendsday evening.
The 3 AMovIeGOerS: September 2014 (Insanely Early Oscar Predictions!)
in Film
You know what September means for the Oscar, Oscar show! That's right, it's time for Garney, Jason, and Jamey to step out on that limb, and make their insanely early Oscar predictions! Even though there's still four months worth of movies to come out, these Oscar experts will put it on the line to predict what nominees and maybe even winners will be announced next February as the best of 2014. It's one of the best annual shows not to be missed!
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Jes Hathaway is the editor in chief of National Fisherman magazine and NationalFisherman.com.
Friday, 19 June 2009
It's been about a decade since the big news in seafood consumption was alarmingly high levels of methylmercury in tuna — leading to warnings that children and pregnant women should limit their consumption or eliminate the fish from their diets altogether.
Those warnings have slowly softened over the years, and always in the background were some grumblings about the accuracy of the assessment and whether selenium might counteract the effects of mercury in ocean fish.
Now a study from the University of North Dakota shows that selenium does indeed affect the absorption of methylmercury and, therefore, must be gauged when recommending consumption restrictions.
Also a poll taken at the International Conference on Mercury as a Global Pollutant shows a majority of scientists saying methylmercury contamination in seafood is not a serious health threat.
So what does this mean for consumers of seafood? Well, I can say anecdotally that the damage has been done. It could take decades for tuna's reputation to recover.
That's how it goes in our media frenzy of 24-hour news coverage. The big, breaking story gets coverage to the point of saturation. The corrections to that story, not so much — especially when they come years later.
That's why the beef people sued Oprah. One bad headline can seriously damage your industry for years (they might thank Dr. Atkins and his diet for early release).
But if tuna should get some sort of relief, it would have to be tempered by the fact that Eastern Atlantic bluefin stocks are in peril. My only advice, as it so often is these days, is to buy American.
National Fisherman Live: 11/06/14
In this episode:
NOAA report touts 2013 landings, value increases
Panama fines GM salmon company Aquabounty
Gulf council passes Reef Fish Amendment 40
Maine elver quota cut by 2,000 pounds
Offshore mussel farm would be East Coast's first


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Winnipeg Free Press - PRINT EDITION
Red River College's culinary institute open for classes
Main Street is cooking again at the Paterson Global Foods Institute
Just try to resist the seductive scent of fresh baking wafting throughout the Exchange District and the heart of downtown.
Go ahead -- just try.
And once that smell lures you inside the grandeur of the oldest skyscraper in Winnipeg, what are the chances you won't want to sit amid marble splendour and enjoy fine dining prepared by aspiring chefs whom you can watch and even chat up as they prepare your meal?
Words such as grandeur and splendour haven't been used in the same sentence as Union Bank Tower for a very, very long time.
There's nary a pigeon carcass left in the 1904 skyscraper across the corner from city hall on Main Street.
Officially, it's the Paterson Global Foods Institute, housing the hospitality and culinary arts programs of Red River College and six floors of student residences. The official opening is Feb. 21. But as tradespeople finish the conversion of the enormous banking section into Jane's restaurant, 30 students have already moved into residence and 300 students are in a state-of-the-art school with opulent kitchens spread over several floors, learning everything from how to bake delicate European pastries, to cooking veal and fresh fish, to tasting wine and beer and spirits to see what goes best with a particular dish.
No, seriously, drinking beer counts as going to school for a post-secondary education.
There are separate programs in culinary arts, hotel and restaurant management, tourism, baking and pastry arts and apprenticeship.
"In a way, we spoil the students," who won't see this range of equipment and facilities anywhere they end up working, said dean Keith Muller.
Who knew a tandoori oven is so small?
"We're the second one in Canada to have one," said Muller, the other school is George Brown College in Toronto, from whence came Muller to preside over the RRC kitchens.
The 105-seat restaurant will initially be open Tuesday to Friday for lunch and dinner, all the cooking and serving and hosting handled by students. Everything in the restaurant, named after the mother of major donor Andrew Paterson -- the marble, pillars, grates, the columns, cornices, moulded ceiling -- has been recovered from the building that sat vacant for decades.
"We've turned learning inside out -- people can see what the students are doing," Muller said. "Their instructors will be guiding and grading them.
"All the daily specials are created by the students. You can converse with the students; we'll even give you a recipe if you ask for it," he said.
On the south side of the building, in what was once Bogart's nightclub, there's a café with the same open-kitchen concept.
"In the summer, we'll have a patio on Bijou Lane," the space otherwise known as a somewhat spiffy alley. And there will be an espresso bar.
Upstairs, Cameron Tait runs the chef-apprenticeship program, whose kitchen is also used for research by companies such as Granny's Poultry.
There's a patio, and each week Tait's students will hold a chef's table and receptions.
A chef's table?
"A gourmet dinner of six to eight courses. They book within 20 minutes of me sending out the email," said Tait.
Everything happens right in the kitchen, a table for the gourmet dinner, while "a grazing would be a standup, really nice and casual."
Muller said the culinary-arts space at the Notre Dame campus was a dungeon by comparison.
Red River College has restored 50,000 square feet and added 40,000 square feet on the space once occupied by the Leland Hotel.
"Everything's shiny new. I'll be stoked when we start working," said student Aaron Clark, a Kelvin High School graduate.
Notre Dame's classroom and kitchen space "was in the basement, no windows," said Daniel Devlin, a Collège Jeanne-Sauvé grad.
"It's definitely exciting being down here. It'll be a little more pressure," taking classes in the later stages of the program by cooking under the scrutiny of paying customers, but worth it, he said.
Each floor of the culinary program has replaced brick walls with large windows, not only offering stunning views of downtown Winnipeg but also allowing downtown Winnipeg to watch students perform kitchen magic.
Take a video tour of the new school at www.winnipegfreepress.com.
Archive video from April 27, 2012 of the construction progress on the Paterson Global Foods Institute.
Republished from the Winnipeg Free Press print edition January 10, 2013 B1
Updated on Thursday, January 10, 2013 at 9:07 AM CST: adds video
12:39 PM: adds archive video of construction progress
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Lemon G is the pride of Ohio, representing the Midwest among all the Dutch and West Coast strains out there. Potent, well-focused and even, this sativa hybrid is a daughter of Original G13. As this is not a pure sativa, relaxing indica effects tend to show up first after consuming Lemon G. Over time, however, the upbeat, euphoric, and giggly sativa effects begin to emerge. Lemon G is a sociable strain and, as the name suggests, has a strong lemon fragrance. Taste-wise, this strain is fairly mellow and does not necessarily exhibit the strong citrus properties found in its scent.
Lemon G Cannabis Strain Details
Sativa Lmg Lemon G
Strain Attributes
- Flavors
- Effects
- Medical
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Lemon G helps patients relieve: Used to help with: Anxiety, Gastrointestinal Disorder, Migraines, Asthma, Muscular Dystrophy
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"I actually passed out from a single hit of some Lemon G from OU in Athens, OH." Read more
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Lemon G Genetics Information


text:
Expat Guide Stuttgart for Working and Living in Stuttgart
InterNations worldwide » Germany expats » Stuttgart expats » Stuttgart Guide
InterNations - a trusted Network & Guide for Expats in Stuttgart
- Build up valuable contacts with like-minded Stuttgart expats
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Enjoy living and working in Stuttgart
Are you an expat living in Stuttgart? You will surely come across many questions, such as ʺWhat documents does the German aliens department require for a work permit?", ʺAre inland flights or national trains the cheaper option to travel from Munich to Berlin?ʺ, or "What can other expats recommend for telecommunication providers in town?"
Looking for all of the information that is important for living and working in Stuttgart can take you hours. However, by using our Stuttgart expat guide you can greatly simplify your relocation to Stuttgart. Beginning with restaurants and nightlife to tips about local infrastructure - the guide deals with all the different facets of the expat life in Stuttgart.
Interested in expat life around the world, though? We have additional information on dozens of countries and cities, from living in Tokyo to living in Zurich!
Latest Entries in Relocation Services & Information
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Are you looking for specific information, such as tax consultants in town or the American diplomatic missions in Germany? On top of our expat guide, you will have access to our expat directory for Stuttgart, which provides you with a complete catalogue of all expat-relevant locales and relocation services in Stuttgart. Moreover, you also can take full advantage of our Stuttgart expat forum in order to look for tips and information from your fellow expatriates.
Become part of InterNations Stuttgart and you'll be warmly greeted with a welcoming Grüß Gott from our expats living and working in Stuttgart.
Of course, InterNations is active far beyond Stuttgart. Please feel free to explore our expatriate guide on living in Dubai or living in Paris.
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Vote List
18 items 202 votes 47 voters 2,194 views by RyanWitalison Power
Ranker more info
Ranker more info
Ra's Al Ghul Fancast
Another Bat villain, Ra's Al Ghul, The Demon who is said to be over 400 years old. Head of the League of Assassins he seeks to restore Earth's balance believing Mankind is ruining the planet. Taken from around the net, add anyone you would like to see play Ra's
The List
Rank Name
- 1Up 16Down 5
- 2Up 18Down 7
- 3Up 16Down 8
- 4Up 16Down 9
Liam Neeson Played the Role in Nolan's Batman series
- 5Up 12Down 8
Christopher Lambert The Highlander, many fans appear to like this choice
- 6Up 10Down 8
added by GamerGrl42 Ralph Fiennes
- 7Up 10Down 8
- 8Up 4Down 2
added by dirk.stensrud Oded Fehr
- 9Up 2Down 0
added by PrithvirajBasu Bill Nighy
- 10Up 1Down 0
added by PrithvirajBasu Jared Harris
- 11Up 9Down 9
- 12Up 2Down 2
added by HumbertoIbarra Iain Glen
- 13Up 0Down 0
added by PrithvirajBasu Jonathan Rhys Meyers
- 14Up 0Down 0
added by PrithvirajBasu Paul Bettany
- 15Up 0Down 0
new! & added by PrithvirajBasu Daniel Craig
- 16Up 0Down 0
added by PrithvirajBasu Ciarán Hinds
- 17Up 1Down 4
added by HumbertoIbarra Edward Norton
- 18Up 3Down 12
added by Kyle Townsend Colin Farrell
19 +
got a blog or website?


text:
The object of the present invention consists of improved nozzles for the lance heads for blowing oxygen from above, in the refining processes.
1. In the combination of a steel making furnace including a vessel for containing a bath including molten iron and slag and a lance for conveying oxygen to the bath, the lance including a nozzle for causing the oxygen to eject from the lance as a jet, the nozzle having for the conveyance of the oxygen a passage defined by walls surrounding the passage and having a first zone defined by convergence of the walls in the direction in which the oxygen is to travel through the nozzle, a second zone joined with the first zone and defined by formation by the walls of a throat in the nozzle, the throat including the smallest cross sectional area of the nozzle passage, and a third zone joined with the second zone and defined by divergence of the walls in the direction in which the oxygen is to travel through the nozzle, the improvement in which in the third zone the walls are concave, at the juncture of the second zone with the third zone the walls are convex, the concave portion of the walls curvilinearly merges with the convex portion of the walls so that no angle is formed, the downstream end of the throat is defined by the boundary between the convex portion of the walls and the concave portion of the walls and the downstream end of the throat is spaced from the downstream extreme of the smallest cross section of the throat a distance equal to one-tenth the diameter of the smallest cross section.
2. In the combination according to claim 1, in the improvement in which a tangent taken at the downstream end of the axial cross section of the portion of the walls defining the third zone is parallel to the nozzle axis.
3. In the combination according to claim 1, in the improvement in which a tangent taken at the downstream end of the axial cross section of the portion of the walls defining the third zone diverges from the nozzle axis in the direction in which the oxygen is to travel through the nozzle.
4. In the combination according to claim 1, in the improvement in which the walls in the first zone are frustroconical, at the juncture of the first zone with the second zone the walls are convex, the upstream end of the throat is defined by the boundary between the frustroconical portion of the walls and the convex walls at the juncture of the first and second zones and the upstream end of the throat is spaced from the upstream extreme of the smallest cross section of the throat a distance equal to one-tenth the diameter of the smallest cross-section.
The nozzles of the lance heads for blowing oxygen have the task of providing the metal bath with the necessary amount of oxygen for refining cast-iron. The oxygen is to be conveyed to the bath with suitable quantities and manners; in fact, the metallurgical results of the conversion depend on e.g. the number and shape of the nozzles through which are formed the jets acting on the metal bath and interacting therewith. It is therefore necessary a careful fluid-dynamic study on the shape of the nozzles generating said oxygen jets.
The object of the invention relates to an improvement in designing the nozzles for the lance heads generating supersonic jets, and above all considers the functions said oxygen jets must perform in their interaction with said metal bath. Said functions tend mainly to reach the following metallurgical results: a high value of the conversion yield for the iron, a good distribution of the oxygen between slag and bath, a high value of the utilization coefficient for the oxygen, the absence of the phenomena of the metallurgical and slag projections, a possibility of repeating the results, a stability of said results even in presence of a variation in the geometrical conditions of the converter and of a wear in the end portion of said nozzles.
In nozzles of the type comprising a zone converging upstream of the throat section and a zone diverging downstream thereof, said diverging zone has a substantially concave shape connecting to the throat zone having a substantially convex outline, instead of the traditional frusto-conical shape.
The outline of the diverging concave zone of the nozzle consists of a single branch of a curve, parabola, circle arc and the like, with its concavity facing the nozzle axis.
The outline of said diverging zone consists of more branches of curves suitably connected to one another by connections, angle points and possibly straight line segments.
The tangent to the nozzle outline, correspondingly to the end of the diverging zone, is parallel to the nozzle axis.
In order that the invention may be clearly understood, it will now be described, by way of example, with reference to the accompanying drawings wherein:
FIGS. 1 and 2 show the axial section of two nozzles according to the invention; and
FIG. 3 is an axial section of a lance including the nozzle of this invention in combination with a steel making furnace including a vessel containing a bath including molten iron and slag.
The following are the characteristic zones, axxially symmetric and not, of a nozzle generating a fluid jet: section or converging zone 1 which is the first portion of the nozzle projecting from the beginning of the nozzle to the throat zone; throat portion or zone 2 which is the portion close to the section of throat 6 of the nozzle (section of the fluid passage with the lowest area), and which projects both upstream and downstream of the latter for a distance of a tenth of the hydraulic diameter D of the section of said throat; the nozzle throat is provided with a cylindrical surface, the length of said throat zone comprises the length of said cylindrical surface plus the portions 0.1D upstream and downstream (FIG. 2); diverging portion or zone 3 which is the remaining part of the nozzle extending from the throat zone 2 to the nozzle end (outlet section 4 of said nozzle) excepting at the most a portion 5 which form the outlet section 4 of said nozzle extends upstream for a tenth of said hydraulic diameter D of said throat section.
As axially symmetric nozzle, outline of the longitudinal section or shortly nozzle outline, the curve 7 is defined which is obtained by intersecting the inner surface of the nozzle (the surface in contact with the fluid passing through the nozzle) with a semi-plane originated on the nozzle symmetry axis.
Having reported the above definitions of general kind, the features of the nozzle according to the invention are pointed out herebelow.
In both figure, the diverging zone 3 of the nozzle does not have the traditional frusto-conical shape, but has a substantially concave shape after a convex starting portion, within the throat zone, where the expansion zone of the fluid current is concentrated. Said outline 7 of the nozzle diverging zone may be formed by the branch of a single curve, parabola, circle arc and the like, or by more portions of different curves connected to each other, or by angle points or straight line portions which originate frusto-conical portions.
Anyhow, said outline 7 so obtained will, in its whole, comprise after said convex zone correspondingly to said throat zone, a concave shape, i.e. suitable to accompany the expanding jet by limiting the radial components of the speed thereof at the nozzle outlet.
Correspondingly to the end of the nozzle, or better to the diverging portion thereof, the tangent to said outline 7 may be parallel to the nozzle axis, as shown in FIG. 2 where angle B is equal to 90�, or diverging outwards for a suitably selected angle A. In this case B will be larger than 90�.
In actual practice, the nozzle is incorporated in a lance 22 extending through the dust collecting hood 21 of a steel making furnace vessel 20 having a steel shell 23 and a refractory lining 24 and containing an iron bath 26 with slag 25 floating thereon (FIG. 3).
The laboratory and metallurgical tests proved that the traditional De Laval nozzles were not sufficient to provide jets with a good interaction with the metal bath in the conditions concerned. Further, their operation was particularly sensitive to the wear condition of their end portion in that moment.
On the contrary, the nozzles of the type suggested allowed: a better conversion of the inner energy of oxygen into kinetic energy; a reduction of the dissipating phenomena; a decrease in the speed radial components in the outlet section; better interaction features of the jets with the metal bath; a lower dependability of the jets features on the wear of the nozzle end portion.
Said features, together with a suitable selection of the nozzle number and the oxygen feeding pressures, led to absolutely satisfying metallurgical results.
It is to be understood that the invention is not limited to the examples shown. It is intended to cover all modifications and equivalents within the scope of the appended claims.
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Story: Nov 24, 2014
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CIA Exhibition: Nov 07, 2014
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Social: about 2 hours ago via Facebook
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CIA again named to "Best in the Midwest" list
Academics . Animation . Courses
Visual Concepts in Illustration
Course No. ILL 371 Credits: 3.0
Faculty John Chuldenko
This course encourages students to develop a confident knowledge of design in illustration, the thinking process, and production techniques necessary to compete in the field of applied arts and prepares illustration students to become working professionals within the marketing communications community. It will motivate the student's visual awareness, teaching the student to conceptualize, design and execute on a professional level. Students become familiar with several techniques used in editorial illustrations, book illustrations, advertising illustrations, as well as many others using an extensive range of materials. Students learn to produce quality illustrations and to be responsible for the conceptual aspects of a project whenever necessary. Offered fall.
Animation Career Review names CIA's Animation and Game Design programs as fifth best in the Midwest, noting our vast classroom/studio space.
Jeff Harter
Adjunct Faculty
Jeff Harter pursued his BFA in Illustration at the University at Buffalo, where he studied under distinguished...more
While at CIA, you'll learn from the masters through our rigorous, world-class curriculum and connect with working professionals to begin your career.