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(1936) · New York
by ELIOT, T.S.
New York: Harcourt, Brace & Company. (1936). Later printing. Owner's name and bookplate on front pastedown, very good in a very good price-clipped dustwrapper, tanned and edges chipped. . (Inventory #: 407941)
by TRENT, Lucia, Ralph Cheyney, Benjamin Musser, edited byNew York : Dean & Company , 1928
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Maureen Griffin
News Articles
Articles by Maureen Griffin
'Reiki is an invitation to hear God's answers'Apr. 19, 2009 Spirituality
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Where is Monroe, North Carolina?
- Where is Rocky River Elementary in the World? 34° 59′ N / 80° 36′ W
It is in the Piedmont region of North Carolina. There are over 800 students. Over 40 classrooms.
We have been learning about latitude and longitude and maps from Our World Our Numbers. This next week when we return to school we would like some help to understand how big your city is and how much different areas of the world recycles in our own mapping project.
Rocky River Elementary School is in Monroe, North Carolina.
North Carolina is bordered by South Carolina, Georgia, Tennessee, and Virginia, as well as the Atlantic Ocean along its eastern coast. Off the coast of North Carolina, out in the Atlantic Ocean, are a string of barrier islands, called the Outer Banks, the site of the Wright brothers first flights, the Kitty Hawk flying experiments.
North Carolina's main geographic features are the coastal plains and the Appalachian Mountains. The sub ranges of the Appalachians located in North Carolina are the Great Smoky Mountains, the Blue Ridge Mountains, Great Balsam Mountains, and the Black Mountains, which have the highest in the eastern United States, Mount Mitchell.
North Carolina is one of the fifty states in the USA. California is all the way across the United States. You can drive there in several days. It's between four and five hours to fly there.
The United States (50 States) joins Canada (10 provinces and 3 territories ) to make up what is known as North America. Bordered by the Pacific Ocean on the west side and the Atlantic Ocean on the east side.
Flight Distance
Monroe to Middleham UK—3924.69 miles / 6316.18 km
Monroe to Sydney, Australia- 9486.7 miles / 15267.36 km
Monroe, NC to Victoria, Australia–9902.31 miles / 15936.23 km
Monroe to Los Angeles California 2146.63 miles / 3454.67 km driving time 2442.18mi / 3930.3km
Monroe to British Columbia Canada and Mrs. Watson's Class 2636.95 miles / 4243.76 km
Monroe to Palmerston North, New Zealand- 8343.44 miles / 13427.47 km


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Lehtonen helps Stars break slide with blanking of WildJan 22, 2014 - 6:26 AM
Ray Whitney, Jordie Benn, Vernon Fiddler and Erik Cole all scored for the Stars, who desperately needed this win as the team had lost nine of their last 10 games entering this game.
"It's been frustrating because we've had a lot of good opportunities inside a game that haven't gone for us," said Dallas head coach Lindy Ruff. "We've started some games really well and all of a sudden a goal can go in and it's a little bit of a letdown. But you know we really gave a key effort and got the saves when we needed them, and the power play was good and the killing was good."
Darcy Kuemper gave up all four goals on 36 shots for the Wild, who had won seven of nine coming into the contest.
"Well we won the opening faceoff and spent 40 seconds in our own zone, that's a bad sign right there," said Minnesota head coach Mike Yeo. "We weren't ready to execute, to get going the right way and it just trickled on from there."
Dallas got on the board at 13:18 of the first period as Fiddler's shot from the high slot hit off Wild and went into the net for his third of the year.
It was a 2-0 game 3 1/2 minutes later as, on the power play, Cole snapped a shot into the right corner of the net from the left circle for his 14th of the season.
The only goal of the second period went to Dallas, as Whitney's wrister on the power play found the back of the net for a 3-0 lead at 13:18 of the frame.
Benn was awarded a penalty shot when Kuemper threw his stick at Benn on a breakaway, and capitalized on his free shot as he dipped his shoulder then slipped the puck around the right pad for a 4-0 lead at 11:22.
Lehtonen stopped nine shots in the third to polish off his 24th career shutout.
Game Notes
Dallas hosts Toronto on Thursday ... Minnesota hosts Chicago on Thursday ... Minnesota had won the previous two contests with Dallas this season ... Lehtonen has 24 shutouts in his career ... Dallas was 2-for-7 on the power play, while Minnesota was 0-for-4.
Jan 21 10:41 PM
- Dallas Goal - Jordie Benn (2), at 11:22.
Wild 0, Stars 4 3rd - 8:38Jan 21 10:21 PM
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Wild 0, Stars 3 3rd - 11:27Jan 21 10:18 PM
End of 2nd
Jan 21 9:45 PM
- Dallas Power-Play Goal - Ray Whitney (6), at 13:18.
Wild 0, Stars 3 2nd - 6:42Jan 21 9:27 PM
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End of 1st
Jan 21 8:46 PM
- Dallas Power-Play Goal - Erik Cole (14), at 16:45.
Wild 0, Stars 2 1st - 3:15Jan 21 8:39 PM
- Dallas Goal - Antoine Roussel (9), at 13:18.
Wild 0, Stars 1 1st - 6:42Jan 21 8:32 PM
1st Period - 20:00
Jan 21 8:10 PM
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Wild vs. StarsOct 13 8:48 AM
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Wild vs. StarsJul 20 8:45 AM
Related News
- Canada beats Finland 2-0 to win world hockey championship May 22
- Blues hope goalie change can slow down Sharks top line May 21
- US beats Czechs at worlds to set up semifinal with May 19
- Hot Tip: Backes excels at deflections for Blues May 19
- Calf sidelines Stars' Seguin in playoffs after Achilles cut May 13
- Stars future with 2 top scorers, need decision on 2 goalies May 12
- Brouwer experience key to Blues' playoff run May 12
- Brouwer experience key to Blues' playoff run May 12
- Blue bloods: Hitch, St. Louis relish chance to keep playing May 12
- Blues advance to Western finals with 6-1 win over Stars May 12
- Blues go with goalie Brian Elliott as starter for Game 7 May 11
- Blues-Stars Preview May 10


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14K Yellow Gold Bar Pin with Sapphires
- Sold for: Start Free Trial or Sign In to see what it's worth.
- Item Category: Jewelry
- Source: Tias
- Sold Date: Sep 17, 2002
- Channel: Auction House Sell similar item on eBay
Early 14K Yellow Gold Bar Pin with Four Sapphires and Nine Seed Pearls. This is a very beautiful filagre design from about the Edwardian period. This beautiful pin features four high quality and magnificent blue color square cut sapphires. The sapphires measure approx. 3mm square, and are estimated to be over .16 carat each. There is well over 1/2 carat of beautiful azure blue sapphires in this pin. The seed pearls measure about 2mm each, and are in very good condition. The clasp is marked 14K. The entire pin weighs 3.9 grams, and is in very good condition.


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Editor's pick: Get up, get down with Sylvan Esso at Treasure Island
Updated 1:34 pm, Thursday, October 6, 2016
Get up, get down with Sylvan Esso as the indie pop duo takes the stage during the last day of this year's Treasure Island Music Festival.
Sylvan Esso is the result of a fateful collaboration by singer Amelia Meath and producer Nick Sanborn, who hail from North Carolina, despite their otherworldly sound. The two met while on the lineup for a show "in a small club somewhere" and have since created groovy, head-bobbing tracks spearheaded by Meath's angelic vocals (her experience singing a cappella with folk trio Mountain Man has served her well), backed by Sanborn's unique beats. The pair's debut single, "Hey Mami!," hit the Billboard charts in 2014, followed by other fan favorites like "Coffee" and last month's "Radio."
While talented musicians in their own right — Meath with Mountain Man and Sanborn as Made of Oak — together Sylvan Esso has drawn large crowds year after year on the festival circuit. Get on board, or get left behind.
Mariecar Mendoza is the arts content editor for The San Francisco Chronicle. Email:email@example.com Twitter: @SFMarMendoza
Sylvan Esso: Sunday, Oct. 16. Treasure Island Music Festival.
Listen to Sylvan Esso songs on The Chronicle's Treasure Island Music Festival 2016 playlist: www.sfchronicle.com/treasure-island


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Doctor insights on:
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What are the signs and symptoms of fibromyalgia?
Several: ? about signs & symptoms of fibromyalgia (FM). FM is label for a characteristic symptom constellation. Laboratory tests & imaging studies provide no signs specific for fibromyalgia. Physical exam reveals certain painful anatomical loci. Orthodoxy has overlooked several physical signs of Joint Hypermobility and sacroiliac joint disorder, both of which are common in people with FM. ...Read moreSee 1 more doctor answer
Fibromyalgia (Definition)
Widespread pain and tenderness on palpation of specific muscle points, associated with variety of other symptoms that include fatigue, sleep disturbances, depression, anxiety, ...Read more
What are signs/symptoms of fibromyalgia? My skin is very tender all over. Barely pushing on it feels like a bruise is there.
See details: Symptoms include chronic, generalized pain with trigger point tenderness, chronic fatigue, headaches, disrupted sleep and GI issues. ...Read moreSee 1 more doctor answer
What are the early signs and symptoms in most patients with ms?
Classical onset: Unilateral loss of vision, loss of balance and coordination, electrical shocks down back on flexion of neck, weakness and stiffness in legs, but also, more subtle, including focal weakness, fatigue, cognitive deterioration, double vision, dizziness, etc. Important, these presentations may be associated with other illnesses, and, in themselves are not diagnostic. ...Read moreSee 1 more doctor answer
What signs and symptoms must be present and observable for a person to be diagnosed with fibromyalgia?
Fibromyalgia : Please see the article that follows. The diagnosis is by tender points or trigger points. www.ncbi.nlm.nih.gov/pubmedhealth/pmh0001463 fibromyalgia is a common syndrome in which a person has long-term, ... Tender points are found in the soft tissue on the back of the neck, ...Best wishes. ...Read moreSee 1 more doctor answer
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Definition: Bipolar disorder or bipolar affective disorder (historically known as manic–depressive disorder or manic depression) is a psychiatric diagnosis for a mood disorder. Individuals with bipolar disorder experience episodes of a frenzied state known as mania (or hypomania), typically alternating with episodes of depression. ...Read moreSee 1 more doctor answer
What are the signs and symptoms of turrets syndrome?
Let me explain: Inherited neuropsychiatric disorder with onset in childhood, characterized by multiple tics and at least one vocal tic. These tics characteristically wax and wane, can be suppressed temporarily, and are preceded by a premonitory urge. Tourette's is defined as part of a spectrum of tic disorders, which includes transient and chronic tics. ...Read more
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Unusual bone growth: Gigantism is known medically as acromegaly and results from abnormal production of growth hormone, usually from the pituitary gland. Children exhibit excessive height as the usual the first sign. Adults with abnormally high levels of growth hormone usually develop a thickened brow, chin, large hands and have problems with bone growth in general as well as collagen problems and heart problems. ...Read moreSee 1 more doctor answer
What are the signs and symptoms of sjorgren's syndrome?
Sjogren's syndrome: Two main symptoms are dry eyes and dry mouth. Other symptoms may include joint pain, swelling and stiffness, swollen salivary glands — particularly the set located behind your jaw and in front of your ears, skin rashes or dry skin, vaginal dryness, persistent dry cough, prolonged fatigue. ...Read moreSee 1 more doctor answer
Are endometriomas benign or mslignant? What is the cause? What are the signs and symptoms?
Benign.: They are benign, and are simply blood collections from endometriosis. They occur commonly in people with endometriosis. The cause is not known. They frequently don't cause any symptoms at all, but they can be painful, or may felt on pelvic exam or seen on ultrasound as a mass. Their biggest significance is that they can be mistaken for something more serious, like ovarian cancer. ...Read more
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- Victor Merritt
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1 POWER LOSS RIDE-THROUGH IN A VARIABLE SPEED DRIVE SYSTEM Copyright Material PCIC Europe Paper No. PCIC Europe AM-7 Tino Wymann ABB MV Drives Austrasse, 53 Turgi Switzerland Abstract - Voltage dips or power interruptions in the grid cause huge problems for the users. The ride-through behavior of frequency converters can be a very good solution to bridge the gap. But how does the whole drive system react in case of power loss? The kinetic energy recovery is only successful when all the important elements in the chain fit together. This paper reconsiders the topic on a power drive system level and gives practical information to the users, based on the experience of a drive manufacturer. Index Terms Grid disturbance, voltage sag, variable speed drive control, power-loss ride-through, industrial power systems, sub-synchronous torsional interaction. I. INTRODUCTION Plant operators depend on reliability of their process controls and of the respective drivers. A failure in the system can be very expensive. The general practice is to introduce redundancy for critical parts of the system and choose safety factors during the design phase. This additional effort makes the whole system robust to component failures. But yet a short voltage dip in the power supply can bring it down within a second. The variable speed drives as one of the largest controlled electrical devices in a plant are of special concern, when it comes to power loss and how to behave under such a condition. Fig. Variable speed drive system and its interfaces The whole installation can be split into three parts: feeding line, power drive system (PDS) and driven equipment, which are all supported by electrically powered auxiliaries (Fig. ). Important for the system integrator are the two interfaces, the electrical and the mechanical. The performance at these points is crucial for the whole design, under regular, but also under exceptional boundary conditions. Interesting enough, hardly any performance requirements are stipulated during ride-through at the interfaces themselves. On the one hand, because the borderline between what can realistically be claimed and what is technically unfeasible is hard to tell during planning phase, on the other hand because it is application dependent, possibly drive-type dependent and interdisciplinary. Writing performance Pieder Jörg ABB MV Drives Austrasse, 53 Turgi Switzerland requirements around the electric interface touches the areas of power systems engineering, automation and control, as well as power electronics; defining requirements around the mechanical interface involves motor control, torsional dynamics and process control issues. Nevertheless, project requirements in process industries normally talk about a minimum power loss period that has to be survived after the network has dropped under a certain level in RMS voltage. A typical requirement would be to stay operational for 4s at less than 85% of nominal voltage. Coming from the semiconductor manufacturing industry, it s also common to define the required time as function of undervoltage level []). As will be shown in the paragraph II of this paper, these requirements leae the supplier of large PDS in a grey-zone with respect to what operational means, since there is no commercially viable energy storage technology to bridge even outages of few cycles. The implicit minimum expectation in industry is: no trip signal raised drive reapplies referenced torque without delay This definition has the advantage of being simple and generally valid, at least at first glance. Conditions can be defined quantitatively or even contractually between the variable speed drive (VSD) manufacturer and the process designer of the end-user. It is generally interpreted as such, that the VSD is providing full torque and following speed reference above the defined grid RMS voltage level and that it is producing no torque while riding-through the power dip. The minimum expectation versus a large PDS is based on experience with the behavior of large electric motors, connected directly on the supply line (DOL motors). As however will be shown in paragraph III, the DOL motor s behavior during a power outage is quite complex, e.g. for small asymmetric undervoltage, it is still providing torque, but with untypical torque harmonics. In reality, the criteria under which network disturbance level the VSD would physically need to stop following torque and if applicable speed reference is much more complex. Depending on VSD technology (thyristor based LCI, voltage source inverter type) there are different electrical limits reached at different stages, inside the power electronic circuit as well as with respect to the interaction of the VSD with the power grid. As a consequence, transition into ride-through (with torque off and frozen speed controller) could very often be deferred as compared to the simple definition. This will be discussed in paragraph IV. In process industries, the expected behavior of the VSD during the grid disturbance is hardly ever described. Riding through usually implies zero-torque at the motor shaft during that time interval. Advanced control strategies with modern power electronics may offer some torque or
2 even full torque under grid-disturbance, however typically traded against another evil like untypical grid or torque harmonics. Relaxing some criteria and limits during transients opens new possibilities. In the following, we will use these definitions: Zero torque ride-through: no or negligible torque applied to load, VSD remains connected to line, with no or negligible current flow ( classic ridethrough). Full torque ride-through: full torque applied to load, but VSD is deliberately operated outside spec for defined criteria or limits. Reduced torque ride-through: reduced torque applied to load, VSD may deliberately be operated outside spec for defined criteria or limits. The engineers designing variable speed wind-power generation (essentially VSDs with opposite power flow) have walked that road to some extent, under the gridowner s expectation to keep generators generating when the grid needs support most. However in this case, the VSDs must not make things worse in the grid, and as a consequence a variety of national grid codes has appeared over the last decade, defining how operation under a degraded grid has to be, depending on the actual or on the statistically most likely root-cause, and on the nature of the disturbance at the point of common coupling PCC [5]. We will discuss operation and the potential consequences under degraded conditions at the electrical interface (i.e. at the VSD s PCC) with examples. The paragraph IV and the summary in Fig. 9, may be seen as a catalogue of things to be checked for full-torque ridethrough. If during a grid disturbance, partial power is of any use for the process, compared to zero in classic ride-through, then this could be implemented for certain classes of network disturbances in form of a reduced-torque ridethrough strategy. This possible reduced-torque ridethrough, very similar to the behavior of a DOL motor, is discussed in paragraph V-B. A further point, which is neglected by the common definition of the ride-through criteria is the transition from ride-through back to normal operation, especially for zerotorque ride-through. Many drive trains are elastic and fast torque steps are not allowed from torsional perspective, hence anything but a slow transition requires at least the knowledge about the mechanical properties of the driven equipment. Since this information is not always available, a softly ramped transition is implemented by default and precious time is lost before full power is again released to the process. Unfortunately, coordination between the VSD and the overriding controller is very often not studied for such a slow transient, leading to oscillations and possibly tripping of the process during that ramp-up phase. Paragraph V-C describes possible ways how to improve performance and reduce time lost during the transition phase. Ultimately, the PDS, the process control system with sensors and actuators and the auxiliary systems (cooling, synchronous motor field exciter, etc.) are all supplied by electricity, usually from the same grid. Whatever options for full-torque or partial-torque ride-through shall be exploited, the auxiliary systems need to support that as well, as will be outlined in paragraph VI. II. ENERGY IN THE DRIVE SYSTEM During a network disturbance the energy flow to the process is interrupted or at least limited. There is energy stored in the installation and it will be consumed by the process load if the energy from the grid doesn t come back. One can spot the energy storage at two places; the VSD and the rotating masses of the process. It might be helpful to calculate the energy-to-power ratio (E/P). Where E is the total energy and P the process power. E/P is a time, namely the time during which P can be consumed until the energy is zero. In reality P changes with speed so this is not an accurate calculation but an indication. A VSD stores its energy in the dc-link. This energy can be considered as very small compared to the power required by the process. Its only purpose is to decouple the input and output side of the VSD. A practical example: For a driven power of 5 MW a motor of 6 MVA is used. In this case the stored energy in the VSD is around 3 kws. The resulting energy-to-power ratio is 6ms.This gives a rough feeling of the order of magnitude of the stored energy in the dc-link. The rotating masses of the process have a certain kinetic energy. If no power is provided from the grid the rotational speed will slow down. How much depends on the total inertia of the whole drive system and the load characteristic of the process. The kinetic energy stored in the system is equal to () where Total inertia of the rotating masses Angular velocity of the shaft During a total power loss the required process energy will be taken from. E.g.: When during a voltage dip % of the energy has been consumed from the rotating masses, the new speed is.9 95%. Calculating the energy-to-power ratio for a real motor (4MW, 494rpm, 95kgm ) gives, applying () and E/P, 8ms. If the process of the end user has a lot of inertia this can be a figure with the magnitude of seconds. Compared with the dc-link, which has energy stored in the magnitude of milliseconds, one can see a factor of thousand between. From the process side the rotating masses have a big influence on the ride-through behavior of the whole PDS. III. BEHAVIOR OF DOL MOTORS Before analyzing the behavior of VSDs, the study of the direct online (DOL) driven motors gives us some basic ideas of the problematic. The active element in this setup is only the motor starter breaker. Usually a motor protection relay is used which opens the breaker under faulty grid conditions. Also a ride-through is possible where the breaker stays closed during a voltage dip. Dips down to zero are frequently called blackout, whereas partial dips (e.g. to 6% on one phase only) are called brownout. A common practice is the automated re-acceleration of the critical motors in a plant as described in [] and []. The drawback is the high reactive power consumption which prolongs the dip additionally and avoids the fast
3 recovery of the voltage (see [3]). Synchronous generators can support the network with introduction of reactive power. Intelligent excitation systems will take care of that. A. Brownout Ride-Through An electrical motor which is connected directly to grid always follows its frequency. The flux in the motor is rotating with network frequency (or a fraction of it when having several poles). This speed is followed even during a brownout. In order to keep the speed of the process, the same shaft power is needed. This implies that the current has to increase to a level that the power is the same as before, as shown in table I. TABLE I DOL MOTOR VALUES DURING BROWNOUT Initial State Brownout Voltage % 8 % Current % 5 % (/.8) Speed % % Motor flux % 8 % Torque % % The increased current leads to a temperature rise in the components. How long and if the drive system can survive a certain brownout depends mainly on the motor design. The protection relay has to trip the breaker if the motor is operated outside the specified range, at least as long as lifecycle cost (due to accelerated ageing) is more important than continuing the process. B. Blackout Ride-Through The influence on the torque and current of a short power loss (ms on a MW induction motor) was simulated. Figure and 3 show the results at the interfaces. Even if the speed just drops a few percent the mechanical and electrical stress can be tremendous. Depending on the system this is not acceptable and the breaker has to trip before the voltage comes back ia [p.u] ib [p.u] ic [p.u].4 Time [sec] Fig. Motor phase currents for a ms total power loss tem [p.u].4 n [p.u] Time [sec] Fig. 3 Torque and speed for a ms total power loss C. Phase Loss Ride-Through Exactly the same simulation has been used but only one phase was lost for ms (Fig. 4). During this asymmetric distortion the torque oscillates at double network frequency but its average is non-zero (Fig. 5). This means that there is still energy flowing to the process and the speed decreases less than before. After clearing the distortion the torque oscillation changes back to network frequency Fig. 4 Motor phase currents for a ms phase loss Fig. 5 Torque and speed for a ms phase loss IV... ia [p.u] ib [p.u] ic [p.u] Time [sec] ELECTRICAL INTERFACE OF A PDS A. When to give up on normal operation.4 tem [p.u].4 n [p.u] Time [sec] The control system of the PDS needs quantitative (measurable and programmable) criteria when to give up on normal operation and to go in a special ride-through procedure. Let s recall two things: hard electrical limitations (overcurrent, overvoltage) have to be respected at any time. Performance limitations (e.g. to prevent increased torque pulsations) have normally to be respected, but might be temporarily relaxed for short transients. The common way of defining when to give up on normal operation and to initiate a classic zero-torque ridethrough with a VSD is specifying an RMS voltage level, under which operation can be interrupted with a signal to the overriding control system, however without tripping the VSD. This definition makes intuitively sense, when thinking of full load operation under a symmetrical undervoltage of the grid: in order to keep full power flow, load current will have to rise inverse proportional to the voltage dip and at some point, it will reach the design limit of the electronic circuit of the VSD (see Fig. 6). Every VSD is designed for full operation with certain undervoltage, compensated by elevated input current. This designed undervoltage operation has to be differentiated against full-torque (Fig. 6, curve 4) or reduced-torque ride-through (Fig.6, curve 3), where some soft performance factors are neglected, compared to
4 unrestricted performance in designed undervoltage operation. The trade-off in performances is illustrated in Fig. 6 with torque, resp. current ripple, but there could be other trade-offs. Fig. 6 Drive reaction on voltage dip with the different strategies: ) designed undervoltage operation with no impact on performance, ) classic zero-torque ridewith performance through, 3) partial-torque ride-through compromise, 4) full-torque ride-through with performance compromise Upon a closer look, this definition seems less intuitive for several reasons:.) When a light power dip occurs under partial or low load conditions, it is equally intuitive to wonder, if deeper dips could not be survived, as the distance to the design limits for the current must be larger. This is in fact the case to some extent, however other limits have to be watched, often not directly measurable as the maximum design current..) The voltage at the point of connect is not independent of the load of the VSD itself. This becomes most obvious at the moment when the VSD is going into zero-torque ride-through and voltage is increasing back to acceptable values immediately, since the load is off now. In cases where the VSD comprisess filter banks and capacitors for reactive power compensation, the voltage may even rise above nominal level due to local overcompensation, even though the fault that originally led to the undervoltage is not cleared yet. For symmetric undervoltage dips, the maximum converter input current would actually be a much better criterion to determine, if a zero-torque ride-through should to be initiated. 3.) In practice, most power dips will be asymmetric, as their typical root causes are phase to neutral shorts (tree falling on overhead line, insulation breakdown resulting in earth fault), phase to phase shorts (overhead lines touching under strong side winds) or inrush events (transformer magnetization, DOL motor start, etc.). Again intuitively, one would expect the same design restriction on maximum current as for symmetric dips to limit operation. However when looking into the grid behavior under such a fault, depending on fault location and transformer configurations between fault and VSD, other design limits may be reached earlier than the maximum design current. Which limits will be reached, depends on the chosen control strategies. Fig. 9 in the following section listss the most important limits. 4.) Another possible motivation to go into a classic zero-torque ride-through is not the dip itself but the recovery of the voltage. If the voltage comes back fast, both the voltage source inverter, as well as the current source inverter topology may have problems. The DC capacitor bank of a voltage source inverter forms a resonance together with grid- and transformer impedance, which is excited by the returning voltage; the reactor current of a line commutated current source inverter may overshoot if the voltage recovery happens just after one thyristor has fired. Then it takes relatively long before the next commutation can take place, and reduce the current again. The overshooting of the dc-link can partly be handled by overdesigning VSDs. Alternatively special control strategies are necessary to prepare the converter for the voltage recovery, one of them is to reduce power to gain current-margin on a thyristor controlled LCI, i.e. partial-torque ride-through. 5.) Another limitation is linked with the electric motor: when the input voltage is lower than the terminal voltage of the motor. For all drive topologies with controlled or un-controlled rectifiers at the input (i.e. not active front-ends AFE), it becomes challenging to rotate flux in the motor, as they create the motor stator voltage directly out of the line voltage. Thus the flux in the motor has to be reduced, whichh for synchronous motors happens only slowly over the rotor s field exciter or by loading the motor with inductive reactive power with the converter. Depending on inverter topology, the VSD can reduce the stator flux directly and very fast before the rotor flux is able to react, thus enabling full torque during short dips. Taking the simple relationship () between flux and voltage (stator resistance can be neglected at nominal speed) one can see why the flux has to be reduced during a voltage dip. Ψ () where Ψ Stator flux vector Stator voltage vector The graphical interpretationn of () is given in Fig. 7 and shows that for a circular movement of the flux, the voltage is equal to the tangential velocity. Fig. 7 The tangential velocity of the flux is given by the available voltage. For undervoltage u uv, also flux needs to be reduced to continue rotating the rotor (and flux) at a given motor speed.
5 The angular velocity is given by the motor speed, and if motor speed shall be kept constant during a voltage dip; but if the necessary tangential speed can t be reached with the available voltage, then the flux needs to be reduced. Reducing flux on the other hand will again reduce torque and speed might drop anyway, if the torque producing part of the current is not increased at the same time. And increasing current limited by the current that already flows to reduce the flux. Understanding these limits and linking them to the grid topology and to potential grid disturbances is of major importance when trying to continue operating under low load condition. It may even be necessary to quantify the expected limits for each load point a priori, so that output power could be reduced actively in those cases where partial operation is beneficial for a process to mitigate the impact of a power dip, i.e. when thanks to advanced process control, advantage can be taken from reduced power, rather than having to accept a period of zero power (see section V-B). however needs agreement with the system operator and usually is limited to times <.5s. B. Full Torque Ride-Through ) Drawing Parallels with Power Systems Experience: As mentioned in the introduction, variable speed wind power generators are required by most national grid codes to continue operation also under severe grid disturbances, very much like every fixed speed synchronous generator (e.g. hydro generator) would do. Thanks to the IEC norm 64-, which describes how to measure performance under grid disturbance, the various grid codes have a quite common way of defining, which grid disturbances have to be tolerated. These represent at the same time also the most frequent disturbances. According our experience, they also correspond to the most likely disturbances at industrial plants. The focus is on both symmetrical and asymmetrical voltage drops. The disturbances are described in terms of depth and duration. The same profiles in depth over time are assumed to happen both on all the three phases as well as on a single or two phases. The phase angle, at which the event is starting, is usually not discussed. Under asymmetric conditions, the phases of the 3-phase supply-grid will change phase relationship and not be shifted by deg against each other anymore. This is usually also not discussed, but is self-understood to some extent, as it depends on the specific installation with its transformer configurations. Fig. 8 shows an overview over what representative grid codes require to be handled. The x-axis shows the duration of the dip and the y-axis indicates the corresponding worst-case depth. In other words, long dips down to zero voltage are so unlikely, that they are excluded. The longer the dip, the less deep it is expected to be. The grid-codes do even go further and describe what the generators, especially the VSD based systems, have to do during the dip. The focus is clearly on supporting the grid. In view of the other process loads and the VSD auxiliaries connected on the same grid, this philosophy also would make sense for industrial drives, only that VSDs of voltage source inverter type usually have passive front-ends (diode rectifiers), which much restricts possibilities. The classic no-torque ride-through known in process industry is also foreseen in power generation, Fig. 8 Typical dip depth and duration requirements for wind power generators, above the curve, the generators have to support the grid with capacitive reactive power! Restoration of pre-dip power is usually also required within a given time. The UK grid code e.g. specifies restoration of active power to 9% of pre-conditions within 5ms for short dips (<4ms), or within s for longer dips after the grid returned to 9%. It has to be noted, that these requirements come from a grid operator perspective. They are characterized by two guiding ideas: first, the classes of grid disturbances of concern shall be well described and cover the most likely events; second, the stability of the grid has high priority and must be supported. Both ideas should also be followed in process industries, latest when power electronic (VSD) loads start to become predominant, compared to other loads. Only describing the classes of disturbances gives electric equipment designers a realistic chance to evaluate bottlenecks and to develop strategies for full-load or partial-load ride-through. And with all the other electric equipment important for the process (auxiliaries, controls), keeping the grid within tolerances must be prioritized in order to prevent secondary faults, which may also bring down the process. ) Challenges and Opportunities for Full Torque Ride-through: Short asymmetric voltage dips of duration and depth as shown in Fig. 8 are the most common grid disturbances also in industrial plants. When only one or two phases are dipping, then still enough energy can be drawn from the grid to provide the desired torque with the electric motor, however the deeper the dip, the more the system will resemble a single-phase supplied load, where power flow is pulsing with Hz. Despite the relatively small DC-link storage, this is a pulsation that still can be smoothened with the DC-link and with the rotational inertia of the load. When trying to implement full torque ride-through strategies for this class of disturbances, several criteria have to be watched, which still may require a zero-torque ride-through at some point. Beyond the obvious maximum continuous designed current of each phase, we foresee at least the categories and issues listed in Fig. 9, that need to be checked. Several issues are even site-dependent and will require at least some routine check-ups before full-
6 torque ride-through can be applied to a specific project. Others are more general and may be resolved by overdesigning or adapting the VSD for the specific application. The list only includes issues with the VSD main-circuit and neglects auxiliaries, which will be discussed in paragraph VI. Fig. 9 Categories of challenges that may need to be addressed before riding through with full torque In order to determine which compromises have to be expected in performance, the two basic classes of gridside power electronics circuits need to be distinguished: controlled or uncontrolled rectifier bridge (diode rectifier front-end of voltage source inverters, thyristor-controlled rectifier of an LCI) voltage source inverter with an active front-end a) Limited Control Dynamics: The first challenge lies in the fact that both voltage as well as phase of the line can rapidly change during asymmetric dips. This puts the PDS control designer into a dilemma: the reference tracking behavior for current (resp. torque) under nominal operation, constrained by a cost effective size of DC-reactor or DC-capacitor, is optimal with timeconstants in the range of a cycle (5-ms), while the recovery of the grid happens faster than this. Adapting the controller to follow the grid voltage disturbances makes the reference tracking nervous, i.e. the torque will tend to overshoot, when operating points are changed. It would also become more susceptible to other noise coming from grid. For all that noise, the converter will look like a negative resistance from the grid side, i.e. current will rise when voltage drops. Experience with the large LNG plant reported in [9] show, that increasing current controller gains by a factor of 3 (thus including roughly another half decade of harmonics into the bandwidth of the current controller of the PDS) increases grid voltage THD by roughly one percentage point; i.e. harmonics between 5Hz (normal bandwidth) and 35Hz (increased bandwidth) are also actively rejected, but the PDS looks like a negative resistor to the grid. When tuned normally (i.e. slower), the current controller will show transient errors at the beginning and at the end of a grid disturbance. Transient control errors resulting from grid voltage changes usually lead to errors in current control, and for sure in one of the two transients of the grid-disturbance in overcurrent. Under high loads, such a overcurrent together with the high fundamental current may reach trip limits. In addition, for LCIs with their current controlled rectifiers, torque errors as function of transient current errors may be applied to the driven load. These transients may be cyclic (at least few cycles) and need to be studied if critical to the load. Transient control errors resulting from phase changes also lead to errors in current, but in LCIs also to untypical harmonics in the current and thus in the load torque. Single and double grid frequency torque pulsations have to be expected during transients. The uncontrolled diode rectifier is the most robust solution in terms of transient errors due to control. b) Non-Uniform Power Flow: In the extreme case of an asymmetric voltage sag with one phase dropping to zero, power cannot be taken continuously from that grid anymore, but will pulse at double grid frequency. Also in less severe dips, the topology of the power electronics and the drive transformers may prevent uniform, continuous power flow. Power flow will be smoothened out of the intermediate storage (capacitor bank or DC-reactor), as long as the load is continuing to be driven with uniform, continuous power, which will lead to oscillations in voltage resp. current. The oscillations may lead to complete depletion and discontinuity on one hand, or to overload (e.g. overvoltage across DC-capacitor) on the other hand. c) Untypical Harmonics: Network disturbances will contain a rich spectrum of harmonics. The frequency converters of VSDs are non-linear loads and especially the integer harmonics in the grid voltage will be transformed into other integer harmonics inside the inverter, which again will result in different current harmonic spectra in the line-side current. During regular operation, a frequency converter will only have integer harmonics of the order 6k ±. This fact is used in design to place parasitic resonances of electric filters on the non-occurring even and triplen harmonics. During grid disturbances, any other integer harmonic can occur, and particularly even harmonics cannot be excluded. Some of them may thus excite parasitic resonances of filters during grid disturbances and their impact needs to be checked. Special attention needs to be paid to filter protection settings, as protection must not trip on grid disturbances ear-marked for full-torque ride-through. Fig. The parasitic resonance of a 5 th harmonic filter () is seen near 4 th harmonic from grid () and may be
7 excited during full-torque ride-through To illustrate a case, which would be sensitive to even harmonics, Fig. shows as an example the fifth harmonic filter of a LCI drive, curve as seen by the VSD at 65Hz and curve as seen from the bus by another VSD, with parasitic resonance near Hz. The diode rectifier and the controlled thyristor rectifier are, as a special case of transformation of harmonics into other harmonics, transforming positive sequence nd harmonics into DC-components on the converter side of the drive transformer. This will after some time-constant lead to the well-known core-saturation of the transformer, with a detrimental impact on the adjacent loads on the same bus. As shown in [6] by Stemmler, the controlled rectifier may be instable for firing angles in inverter mode between..45 degrees, if a positive sequence nd harmonic occurs over certain time under grid imbalance. Depending on reactor size, the stable range will be extended from 45 degrees downwards. As shown in the same publication, the effective reactor size as function of the physical reactor size, together with active control virtual inductance matters for stability. Contrary to the reported HVDC transmission application, drive transformers have smaller saturation time constants (approximated by L m/r m) and may consequently already saturate during a long full-torque ride-through. On a plant electric system level, power electronics controls play an eminent role in two ways: For the VSD under investigation itself, whether its control scheme is capable of preventing core saturation also at small inverter firing angles. For other VSDs in the plant, if their complex admittance, exhibited to the grid at nd harmonic is amplifying positive sequence voltage disturbance as function of nd harmonic current, thus pushing transformer core saturation. The important role of the complex admittance, resp. impedance of controlled active loads is further elaborated in the next section or in [7,8 and 9]. The untypical harmonics generated by a network disturbance into the VSD may also appear in the currents on the load side and finally as untypical torque harmonics in the electric motor air-gap. This is specially the case for LCI-type VSDs. The most likely harmonics to occur under network disturbance and full-torque ride-through however are the X and X torque pulsation, which should not pose problems to the driven load, as these frequencies may occur for mechanical reasons as well and should be accounted for, at least to some extent. d) Grid-Unfriendly Load Behavior: The VSDs, especially the ones with controlled front-ends (VSI with active front-end and LCI with controlled thyristor rectifier) have to be understood as complex, time-variant impedances or admittances on the grid. Other industries, such as the electric railway traction, put very conservative criteria on this complex admittance. They typically require passivity for the VSD admittance over the whole frequency domain. Such criteria have to be fulfilled also during grid disturbances. The VSD control strategy for full-torque ride-through could also pose a problem to the grid and its recovery from the disturbance. Simple strategies tend to load phases with undervoltage more than healthy phases, which may lead to a knock-on effect on the grid and on auxiliaries. Having a look at grid-codes for wind power generators again, grid-operators have started to require capacitive reactive power support to the unhealthy phases. V. MECHANICAL INTERFACE OF A PDS A. General Behavior The VSD can provide regular operation for dips of about -3% depth (remaining 7-8% of voltage) then it switches usually to zero-torque ride-through. The torque will be reduced to zero or even a small negative values in order to support the dc-link with energy (for voltage source inverters). This prevents large inrush currents and voltage overshoots when the voltage comes back and also keeps the induction motors magnetized. The technique is also known as kinetic recovery and was discussed here [4]. The advantage is that the VSD doesn t have to trip and is able to re-accelerate the motor immediately after the distortions is cleared. The crucial point is that the rotational mass does not drop under the mechanical system s minimum speed or even come to a stop during the dip. This criterion is process depended and cannot be generalized. B. Reduced Torque Ride-Through Depending on the nature of the power dips, different supervision rules could be applied in parallel, each of which can initiate a classic ride-through reaction. The items to supervise correspond to the issues identified in the previous paragraph. For cases, where the process could profit from getting partial power, a reduced torque ride-through could be initiated in a similar fashion. The rules however would have to be carefully selected and will largely depend on the application and the plant. The integration of partial-torque ride-through into a plant-wide control design needs to be thought through. Obviously, a compressor will approach the surge-line slower as compared to a classical zero-torque ridethrough and so will buy time for the compressor performance control and the process control to adjust valve positions. Wherever the outer loop may end-up being faster than the speed controller of the VSD under partial-torque ride-through, the cascade of controls may need to be extended with dynamic resets (dynamic antiwindup). Fig. shows the full decision tree when considering all three options for riding through grid disturbances in a concrete project. The decision tree is guiding the work during project engineering, but needs to be implemented in the PDS controller for later operation as well. The topics in the rectangular blocks are defining the studies to be done during project engineering: the disturbance types need to be addressed, an impact study for trying to run full torque under those disturbances needs to be carried out, then VSD internal ultimate limits, i.e. effects where zero-torque ride-through becomes mandatory, need to be defined and last but not least, the dependency of those criteria ( ultimate limits ) on load needs to be studied.
8 The torque control loop should ideally be put to the actual load torque. Load might have changed over the time the grid was disturbed and needs to be identified. Special attention needs to be given to the build-up of torque at this stage. The torque increase could be made very sharp from electric perspective, but then might excite torsional resonances. Torque can be reapplied immediately, if the disturbance had lasted less than ¼ period of the dominant torsional natural frequency between motor and load. For longer disturbances, load torque has to be ramped back with slow ramps or with steeper ramps, where the reference was filtered at the critical frequencies. If the controls are tuned fast for strong disturbance rejection, then there is also the risk that those fast controllers un-damp the lower torsional modes, because the torsional resonance interacts with the control circuit, which may even result in continued torsional excitation, as reported in []. The speed controller needs to be re-initialized at actual speed, which may have dropped over the time of the griddisturbance. It must only be released from anti-windup by the time the inner loop is again following the reference. The same is true for any overriding integrating controller. VI. AUXILIARY AND CONTROL POWER Fig. Design tree for utilization of all advanced ridethrough features. The quadratic sub-process blocks indicated preparatory studies to be carried out. Already the classic zero-torque ride-through could be improved by going from cause based initialization criteria to effect based initialization criteria. An example could be to wait for an over-current rather than to go into zerotorque based on grid-voltage levels, which don t pose a problem to operations per se yet. Criteria for full-torque ride-through are defined in an impact study, which essentially checks the impact of dropping performance in certain points, in order to continue full torque under disturbance. The list of criteria gives the ultimate pain threshold. For those thresholds, load dependency has to be evaluated in a second study, in order to know the derating levels to allow partial load ride-through. C. Transition back to normal operation At some point, the grid disturbance will disappear and the PDS has to recover from ride-through and go back to normal operation. The topic is hardly ever addressed in specifications. There are two control loops that have to return working normally: The inner torque control loop and the outer speed control loop (if used). Both loops should be reinitialized to their present state of operation. After full-torque ride-through, there will be no transition back to normal, as both loops have kept on working. Both after reduced-torque as well as after zero-torque ridethrough, initialization is necessary. During the different grid disturbances that could happen, also the auxiliary and control power is affected when not fed from a different source. This has a nonnegligible effect on the ride-through behavior of the whole drive chain. The auxiliary voltage powers small 3-phase induction motors for cooling. The effect of different failures is analog to those on the DOL motors in section III. During a brownout, the coolant flow is still given as long the frequency stays stable. But the auxiliary motors will overheat and their protection relays may trip at a certain point. In contrast, a total auxiliary power loss implies an immediate stop of the coolant flow (usually water or air). The heat cannot be transported any longer and the heat sinks of the semiconductors keep heating up. As the coolant temperature at the power-part outlet is no longer meaningful for the self-protection, the time without auxiliary power is limited to some seconds by the drive software. The used delay before the trip depends on the thermal capacity of the heat sinks and on the actual load. If the main power fails together with the auxiliary power of course the classic zero-torque ride-through time can be quite large due to reduced losses. A redundant line from a different sub-station or bus bar can be used to increase reliability of the cooling systems. Especially in the case where auxiliary power distortions are more common than main power distortions. The control power is not allowed to fail at any time. The control boards need the energy in order to control the VSD and also provide the protection. That s why the control line should always be backed-up by an external (from the plant) or an internal UPS. The cooling of transformer and motor is for short interruptions of several seconds less critical than the one of the VSD. The thermal time constant could be minutes whereas the VSD has seconds. A brownout instead could also be critical to those components because the cooling fans might overheat. Also to consider are the switchgears and main circuit breakers. They should not open during a network distortion. This might be due to control power loss or the
9 protection might trigger. If the PDS shall survive grid disturbances, the whole factory protection and auxiliary supply concept has to be designed accordingly. For synchronous motors also an excitation unit is needed, which is fed from the auxiliary power or with an additional transformer from the main power. As the excitation unit is an active device it reacts to network distortions and needs to do a ride-through itself if necessary. During an excitation unit ride-through no current will be driven in the rotor windings and the flux decreases with rotor time constant. With reduced flux limited torque can be produced in the motor. The rotor time constant limits the ride-through time which itself depends on the motor size. VII. CONCLUSION Short voltage dips down to about 7-8% remaining voltage can usually be handled without losing performance. For deeper voltage sags, it may still be possible to provide full power, but only by compromising on soft performance criteria, e.g. at the cost of increased harmonic pollution to the network. This temporary operation with less performance, but providing full torque to the load, is defined as full torque ride-through. A special design of the PDS might be required to handle overshooting when the voltage comes back and in case of symmetric dips provide the additional current that is needed in order to compensate for the voltage (/.7 = 43% current). Dips below this threshold will be handled as zero or reduced torque ride-through. State of the art is the zero torque ride-through. The drive tries to survive the distortion without tripping and continues the operation after the voltage comes back. Reduced-torque ride-through is very complex and requires an interdisciplinary approach. But there we see also a major opportunity for improvement in the future. Especially with compressors with their small rotational inertia, which are quickly running towards surge, already for short dips of some ms, a reduced torque ridethrough could help to stay away from surge longer and to gain time for valves to adjust load. In order to keep on operating the PDS with partial torque, the exact limitations have to be determined in studies, e.g. in simulation, and these limits need to be defined as function of load. Crucial is also the interaction between process controls and the PDS controls. When the PDS runs into a torque limit (e.g. due to an undervoltage) it has to communicate that in a proper way to the process control. The process control can react and prevent integrator wind-up. In a scenario with partial-torque, advanced anti-windup schemes might be necessary such as dynamic reset. These schemes will have to ensure, that the overriding controller doesn t wind-up or overshoot, when the PDS controllers are working at reduced performance. Special attention needs also to be given to auxiliaries that need to be supplied during grid disturbances as well. Mostly UPS will be used to buffer the control circuits, whereas cooling circuits are designed in a robust way for the majority of grid disturbances. VIII. REFERENCES [] Robert A. Hanne et al., Minimizing Refinery Upset During Power Interruption Using PLC Control, IEEE PCIC Conference Record, PCIC-9-5 [3] Math H. J. Bollen, The Influence of Motor Reacceleration on Voltage Sags, IEEE Transaction on Industry Applications, Vol. 3, No. 4, Jul/Aug 995 [4] Kai Pietiläinen, Voltage Sag Ride-Through of AC Drives, Stockholm, KTH, Royal Institute of Technology, 5 [5] T. Bublat, T. Gehlhaar, Comparison of high technical demands on grid connected wind turbines defined in international Grid Codes, EWEC European Wind Energy Conference & Exhibition, 8, Brussels [6] H. Stemmler, HVDC back-to-back interties on weak AC systems second harmonic problems, analysis and solutions, CIGRE Symposium, 987, Boston [7] L. Harnefors, L. Zhang, and M. Bongiorno, Frequency-domain passivity-based current controller design, IET Power Electron., vol.,no. 4, pp , Dec. 8 [8] L. Harnefors, M. Bongiorno, and S. Lundberg, Input-admittance calculation and shaping for controlled voltage-source converters, IEEE Trans. Ind. Electron., vol. 54, no. 6, pp , Dec. 7 [9] P. Jörg, A. Tresch, M. Bruha, A model based approach to optimize controls of a large LCI VSD for minimal grid-side sub-synchronous torsional interaction, IEEE PCIC-Europe 3, Istanbul Turkey [] P. Jörg, A. Lenzi, V. Depau, Optimization of Transient Behavior of Complex Turbocompressor Shaft Lines, in IEEE IAS Annual Meeting Record,, Orlando [] PLS Standard SEMI F47: Required voltage sag tolerance for semiconductor fab equipment, Power Standards Lab, Alameda CA, U.S.A. IX. VITA Tino Wymann graduated from the Swiss Federal Institute of Technology Lausanne in 9 with a M.Sc. in Power Conversion and Systems. The same year he joined the R&D department of ABB Medium Voltage Drives. Since he s working in the system design team which supports sales with the technical aspects of variable speed drive solutions in different industries and applications. Pieder Jörg received his M.Sc. degree 995 from the Swiss Federal Institute of Technology, Zurich. He joined ABB at Corporate Research in the area of power electronics. In he joined the business unit Medium Voltage Drives as head of product development. Since he is focusing on business and technology development for demanding drives applications. He has been involved in various studies and improvement projects involving large VSD systems with demanding rotor dynamics. [] Rekha T. Jagaduri et al., Field Evaluation of Automatic Restart of Essential Motors Using Microprocessor-Based Protective Relays, IEEE PCIC Conference Record, PCIC--8
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1. Activate Poison of the Old Man to decrease the opponent's LP by 800.
2. Activate The Warrior Returning Alive and choose Elemental Hero Bubbleman.
3. Special Summon Bubbleman and draw two cards.
4. Activate Skyscraper.
5. Summon Elemental Hero Sparkman.
6. Enter Battle Phase and attack Mad Dog of Darkness with Sparkman.
7. Attack with Bubbleman.


text:
You may use any designs, techniques, instructions from any DVD's, downloads or kits you have purchased to create items for sale for charity or profit so long as all of the items are handmade with no mechanical processes.
You may not, under any circumstances sell, distribute, copy or otherwise breech copyright of any DVD's, instructions, research, images or other items, whether given freely, or purchased from Gina Barrett / Gina-B Silkworks.
Should you wish to license any designs, or become a distributor, please contact Gina-B Silkworks.


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Our top publishers:
(Ex. VAT)
Our Part #: 802684 |
delivered via Email
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Bamboo automatically monitors and runs builds according to your preferences, even across different locations and platforms. It also helps identify and highlight trends, patterns and linkages across your builds and provides personalised feedback immediately alerts you of build results and failures via email or IM.


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Kolkata, Nov 8: Even as a pall of gloom descended on the Eden Gardens after retiring legend Sachin Tendulkar became victim of a dubious decision in the first Test here today, West Indies spinner Shane Shillingford said his "job was to appeal".
Off-spinner Shillingford returned figures of 4/130 on day 2 and one of his wickets included Tendulkar. It turned out to be a controversial dismissal as TV replays suggested that the ball was climbing and would have missed the stump.
Asked whether he was happy with the way Tendulkar was dismissed, Shillingford said: "That's a funny question... In terms of, at the spur of the moment, it's every bowler's reaction to appeal one time. But when I got in and I had seen it and stuff... At the end of the day, the umpire made his decision. It's my job to appeal, so these things happen in the game."
Rohit Sharma stamped his class by hitting a sparkling 127 on debut as India recovered from a top-order collapse to take a firm grip of the Test with a 120-run first-innings lead. Ravichandran Ashwin (92) was also going strong at stumps. But Shillingford said they're still hopeful as the wicket had "eased out".
"The match is still wide open. It's only the second day, tomorrow is a very important day for us. We have to come out and stick to our plans and be patient. When we get them out, it will depend on how we will bat and stuff.
"Definitely (the wicket had eased out...) After lunch it really slowed down a bit. That's when you had to be a little more tighter as opposed to more attacking. The batsmen, they were really patient as well and put away the bad balls."
He said things did not go their way as Sharma and Ashwin batted really well. "Nothing wrong with us... That's cricket. Sometimes you get early wickets and some batsmen come to consolidate and that's when you have to dig deep. I thought Sharma and Ashwin, they bat absolutely well, they stuck to the task and bad balls, they put away. That's the kind of wicket; they know their wickets, they handled it really well."


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Have a Tax Question? Ask a Tax Expert
If your disability benefits is based on your work and you received at least $3000 in 2007 - you are eligible for the stimulus rebate regardless of your husband income.
As your filed joint return - the amount of rebate depends on total taxes paid - to find out the exact amount - please use this calculator - http://www.irs.gov/app/espc/


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FBT Splitter/FBT Coupler
Fused Bi-conical Taper technique is tied to two or more fibers, and then melted in a cone machine, pull tensile and real-time monitoring of changes in splitting ratio, the splitting ratio to meet the requirements after the end of the melt stretching, and wherein one end of a fiber optic reserved ( The remaining cut off) as the input terminal and the other end a multitude of road outputs. Mature tapering process can only pull 1 × 4. 1 × 4 or more devices, with a plurality of 1 × 2 connected together. Then the overall package in the splitter box.
(1) pull taper coupler over twenty years of history and experience, many equipment and processes simply follow the only development funds only a few of the PLC tenth or hundredth of a few
(2) Raw materials only readily available quartz substrate, fiber optics, heat shrink tubing, stainless steel pipe and less plastic, a total of not more than $ 1. Investment in machinery and equipment depreciation costs less, 1 × 2,1 × 4 and other low-channel splitter low cost.
(3) splitting ratio can be real-time monitoring, you can create unequal splitter.
(1) Loss of light sensitive wavelength ships according to the wavelength selection device, in this triple-play during use is a fatal defect, since the triple play of light transmitted signal 1310nm, 1490nm, 1550nm, and other multiple-wavelength signal.
(2) poor uniformity, 1×4 nominal about 1.5dB away, 1 × 8 or more away from larger, can not ensure uniform spectroscopic, which may affect the overall transmission distance.
(3) Insertion loss varies with temperature variation is greater (TDL)
(4) multi-demultiplexer (e.g., 1 × 16,1 × 32) volume is relatively large, the reliability will be reduced, the installation space is restricted.
Related article:


text: All the excitement and relaxation you want with this spacious Cormorant model in the highly desired Spring Run bundled golf community! This home sits on the 15th fairway with views of the lakes and beautiful palms. Well appointed newly remodeled kitchen with glass door cabinets and granite counter tops. Spacious open floor plan with large lanai. Lowest transfer costs for Golf club privileges Call TODAY to book. Newly renovated clubhouse invites you to dine and enjoy all the social events in an elegant setting. Season and off season rates available


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2011 Audi S4 for sale ebay
[Total: 0 Average: 0/5]
2011 Audi S4 Premium Plus
US $23,500.00Woodburn, Oregon, United States
Car specification:
VIN (Vehicle Identification Number): waudgafl3ba016076Year: 2011Fuel Type: GasolineMake: AudiMileage: 53,700Model: S4Exterior Color: BlueTrim: Base Sedan 4-DoorInterior Color: BlackEngine: 3.0L 2995CC 183Cu. In. V6 GAS DOHC SuperchargedTransmission: ManualDrive Type: AWDWarranty: Vehicle does NOT have an existing warrantyNumber of Cylinders: 6Vehicle Title: Rebuilt, Rebuildable & ReconstructedBody Type: Sedan


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15418 27th Street, Vicksburg 49097
See more homes for sale in Vicksburg, MI
This property has been Sold!
07/01/2016 at $280,000
Elegant 5 Acre horse property with double brick wall construction features 4 bedrooms 2 full baths. Large kitchen with new stainless steel appliances included. 2 barns, 1 is 36'X 80' and 2nd is 18'X 25' & 2 fenced pastures. Goat house and detached 3 car garage with newer garage doors. Updated roofs and heating system. Main floor laundry. Master bedroom with large walk in closet.
Property Information
- Status
- Sold
- Address
- 15418 27th Street
- City
- Vicksburg
- Zip
- 49097
- County
- Kalamazoo
- Township
- Brady Twp
- Possession
- at closing
- Total Finished SqFt
- 2,008
- Above Grade SqFt
- 2,008
- Garage Desc.
- 3, Detached
- Water
- Well
- Sewer
- Septic System
- Year Built
- 1865
- Taxes
- $4,248
Rooms and Land
- MasterBedroom
- 2nd Floor
- Bedroom2
- 2nd Floor
- Bedroom3
- 2nd Floor
- Bedroom4
- 1st Floor
- FormalDining
- 1st Floor
- Kitchen
- 1st Floor
- Laundry
- 1st Floor
- Living
- 1st Floor
- Basement
- Michigan Basement
- Cooling
- Central
- Heating
- Forced Air, Propane, Radiant
- Acreage
- 5.0
- Lot Dimensions
- Appliances
- Dishwasher, Garbage Disposal, Range, Refrigerator
- Fireplace Desc.
- Living
- Features
- All Window Treatments, Ceiling Fans, Garage Door Opener, Security System, Water Softener/Owned, Wood Floor
- Exterior Materials
- Brick
- Exterior Features
- Fenced Back, Porch(es)
Listing Video for 15418 27th Street, Vicksburg MI 49097
Mortgage Calculator
Listing Broker
Listing Courtesy of Chuck Jaqua, Realtor, Inc.
Office Address 414 West Milham Road
Listing Agent Dan Berryman
Listings last updated: . Some properties that appear for sale on this web site may subsequently have been sold and may no longer be available.
Our Michigan real estate agents can answer all of your questions about 15418 27th Street, Vicksburg MI 49097. Real Estate One, Max Broock Realtors, and J&J Realtors are part of the Real Estate One Family of Companies and dominate the Vicksburg, Michigan real estate market. To sell or buy a home in Vicksburg, Michigan, contact our real estate agents as we know the Vicksburg, Michigan real estate market better than anyone with over 100 years of experience in Vicksburg, Michigan real estate for sale.
The data relating to real estate for sale on this web site appears in part from the IDX programs of our Multiple Listing Services. Real Estate listings held by brokerage firms other than Real Estate One includes the name and address of the listing broker where available.
IDX information is provided exclusively for consumers personal, non-commercial use and may not be used for any purpose other than to identify prospective properties consumers may be interested in purchasing.
All information deemed materially reliable but not guaranteed. Interested parties are encouraged to verify all information. Copyright© 2017 MichRIC LLC, All rights reserved.


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We just wanted to share the happiness and the GREAT in the people of Racine again in case you missed them. Here are the tops stories from the last 2 weeks. From firefighters getting warm coats for an entire school, to cops and kids shopping, to someone paying it forward to a little boy that got a huge birthday surprise we thought we would share them all and show there is so much GREAT in this town!
Racine Firefighters provide winter coats for Janes School
Military wife would like to say thank you to Jims Garage Door Service
THANK YOU! Woman pays it forward in Racine standing in check out line
Thank you Racine Uncovered readers, YOU HELP MAKE THE DIFFERENCE!
Police Officer Jay had a huge surprise for his 4th birthday! Thank you Racine Police!