text:
Pets on Pinterest | Manchester Terrier, Plott Hound and Komondor
The Love of Animals!!!
DOG BREED YORKIES!
Tibetan Mastiff I, Mastiff Animals, Mastiff Dogs, Red Tibetan Mastiff, Mastiff Red Tibetan, Tibetan Mastiffs, Dog Breeds
Tibetan Mastiff...everyone is always talking about how cute and fluffy they are. HA. Tibetan Mastiff are one of the most aggressive dog breeds in the world. They make Pitts look like Mother Teresa.
"Don't mess with me... it's a bad hair day" -Tibetan Mastiff- the world's fiercest dog breed
chinese dog breeds | Specimens of this breed are endowed with a ferocious temper ...
red_tibetan_mastiff_THESUITEWORLD.jpg (580×435) #dog #mastiff #animal
Tibetan Mastiff. I believe this breed is bred to fight off bears. :O
World’s most expensive Red Tibetan Mastiff at 1.5million
Tibetan Mastiff...seriously...that thing looks FIERCE!
Most Aggressive Dog Breeds Red Tibetan Mastiff
Red Tibetan Mastiff #dog #mastiff #animal
Beautiful Cat, Breeds Of Cats, Animals, Cats Breeds, Pet, Bobtail Cats, Cat Breeds
Featured Cat Breed of the Day, The American Bobtail, brought to you by Catster, via Nothing but Kitty CATS http://sulia.com/my_thoughts/0cbef6ea-8891-4210-a445-35d447f6ba45/?pinner=119686333
American Bobtail, - The American Bobtail is a relatively new and uncommon breed of cat which appeared in the late 1960s. It is most notable for its stubby "bobbed" tail about one-third to one-half the length of a normal cat's tail
American Bobtail - The American Bobtail is a short-tailed cat, with a medium to large frame. Its tail should be clearly visible above the back when the cat is alert, not exceeding the hock in length
The American Bobtail breed of cat, is so-called because of the stumpy, half tail that it sports.
American Bobtail - The American Bobtail is a relatively new and uncommon breed of cat which appeared in the late 1960s. It is most notable for its stubby "bobbed" tail about one-third to one-half the length of a normal cat's tail. This is the result of a cat body type genetic mutation affecting the tail development, similar to that of a Manx. The cat is not related to the Japanese Bobtail despite the similar name and physical type.
American Bobtail Cats - http://www.healthiana.com/2013/08/american-bobtail-cats.html
American Bobtail - pusakal lng yan dito sa kanto,lol!
Animals, Ridgeback Pups, Dogs, Pets, Puppy, Favorite
Rhodesian Ridgeback puppie! I like that you can see the ridge down the one puppies back!
The Attraction and High Maintenance of the Rhodesian Ridgeback #GuestPost #Dogs #Pets
Future Shamy! (sheldon + amy) Rhodesian ridgeback puppies - my favorite breed!
Our next dog! Rhodesian Ridgeback puppies.... rhodesians are such good dogs!
rhodesian ridgeback puppies. in my top 5 favorite breeds
rhodesian ridgeback pups - my fav dog - so want one!
My favorite dog breed, the Rhodesian Ridgeback
My next dog: rhodesian Ridgeback puppy
Newfoundland I Have Always Wanted One of These
Newfoundland Dogs, Animal Pictures, Animal Attraction, Random Pins, All Animal, Dogs Newfoundlands, Animals 3, Newfoundland Animals
Papillion-French for butterfly (it's all about the ears) Friendly, elegant, lively, dainty little toy dog with over sized ears...cutie pututie!
Animals, Papillon Dogs, Pet, Butterflies, Puppy, Dog Breeds, Friend
Papillion-French for butterfly (it's all about the ears) Friendly, elegant, lively, dainty little toy dog with over sized ears...cutie
Papillion and technically this is the phalene version of the papilllion due to the dropped ears.
New to List?: Phalene - France. This breed is the drop-eared version of the Papillon
Road's End -Papillons - Phalenes: Road's End Up-Coming Phalene Puppies
I even love the drop eared version the Phalene!
Phalene drop-eared version of the Papilion
Papillon, I want one of these soooo bad!!
Phalene Papillion
Komondor - THIS IS the dog lol. I had to click on through because it looked like a wind blown hay-stack !! Had to put this on my "funny .." board :)
Komondor Jumping, Animals, It S, Dogs, Mop Dog, Pets, Jumping Komondor
Komondor. This has been my dream pet for upwards of 5 years. Ever since someone had three in town, just passing by, I've loved them.
This is a picture of a dog jumping...I love these mop dogs, they look so funny when they are moving
What the heck is this? It's a dog! A Komondor dog, showing off on an agility course.
Komondor dogs look crazy! It's a traditional Hungarian guard dog.
Komondor | komondor jumping komondors animals
Jumping Komondor that is a DOG HAHHAHAHAHHAHA
koomoodor dog | Komondor Dog | Cute animals
Jumping Komondor Is this really a dog???
i want the mop dog!!
Animals, Dogs, Toy Poodles, Pets, Toys, Teacup Poodle, Puppy, Adorable Poodle, Poodle Puppies
Toy Poodle - 2nd most intelligent dog. http://en.wikipedia.org/wiki/The_Intelligence_of_Dogs Brightest Dogs! Understanding of New Commands: Fewer than 5 repetitions. Obey First Command: 95% of the time or better.
Toy Poodle | Toy Poodle Information and Pictures, Toy Poodles, Teacup Poodles
《♡~ @gustlily 》 Adorable Poodle Puppies
Afghan Hound beautiful flowing coat..alot of grooming to keep in good shape.
Hound Dogs, Afghans, Galgo Afgano, Dogs, Animals Dogs Afghan Hounds, Dogs Afghanhounds, Beautiful, Sighthound, Dog Breeds
Afghan Hound beautiful flowing coat..alot of grooming to keep in good shape.... Mine was so sweet and smart, he looked just like this beauty.
Afghan+Dog | AFGHAN HOUND Dog Pictures, Photos, and Images, Photo Gallery of AFGHAN ...
Afghan Hound...when I was little, this is the kind of dog I wanted. :)
Afghan Hounds - beautiful but dumb I had one and he was a handful. :)
Afghan Hound Had this color Afghan as a kid named Sheba!!
Afghan Hound #dogs #afghanhounds #blondes
Afghan Hound... Absolutely Beautiful!
Thanksvalley Bulldog, Valley Bulldogs, Animals Pets, Amazing Food, English Bulldogs, Animal Love 3
Valley Bulldog - Combining qualities of the Boxer and the English Bulldog, the Valley Bulldog is sometimes calm and easygoing-especially around the house-but likes to mix things up with the occasional bout of goofy and boisterous play. Strong and intelligent, the Valley Bulldog needs firm but positive training when young.
Valley Bulldog - I have 2 at home.
Manchester Terriers, Dogs, Stuff, Adorable Animals, Pets, Toys, Amazing Animals
Manchester Terrier.....Buttons! The very 1st dog I remember my family having as a child!
Manchester Terrier - Toy - Click image to find more Animals Pinterest pins
Toy Manchester Terrier --- Hmmm, maybe max isn't a min pin after all?!?!
Manchester Terrier / Gentleman's Terrier / English Toy Terrier
@KatieFeil Elongated Marta! Manchester Terrier -
Manchester Terrier - Toy....LOOKS LIKE OUR BABY!
Manchester Terrier - Toy or this one ❤
Kitty Cats, Cheetoh Cat, Random Pins, Paige S Pins, Cutest Animals, Animal Lover Cats, Baby Animals, Cheetoh Pets, Cheetoh Animals
Plott Hound..don't see them often..love U thanks 4 sharing
Dogs, Favorite Pins, Hound Animals, State Dog, U.S. States, Dog Breeds, Plott Hounds, North Carolina
The Plott Hound was officially adopted as the State Dog of North Carolina on August 12, 1989. (Session Laws, 1989, c. 773). <3
The Plott Hound was officially adopted as the State Dog of NC on August 2, 1989
http://ncpedia.org/sites/default/files/plotthound2.jpg Plott hound
Plott Hound - think this dog looks like Valentine!
Plott Hound. This looks like my boy.
Pharaoh Hounds, Hound Dog, Hound Photo, Dogs Breeds, Paraoh Hound, Animal, Pharooh Hound
Pharaoh Hounds What a perfect addition this beautiful creature would make to my little family!! I must have one!! :)
The Pharaoh Hound is a breed of dog and the national hound of the Mediterranean nation of Malta.
Pharooh Hound photo | ... tolly and merrick from nefer temu pharaoh hounds the pharoah hound is
The Pharaoh Hound-The Pharaoh Hound is a breed of dog and the national hound of the Mediterranean nation of Malta. Its native name is Kelb tal-Fenek (plural: Klieb tal-Fenek) in Maltese, which means "rabbit hound". The dog is traditionally used by some Maltese men for hunting.[1] The breed has no conclusive links with Ancient Egypt and its name in English is a 20th century fabrication. it is the only known breed to 'blush', when excited its nose and ears turn red..
Add a pharaoh hound to my family *Checked off!! ;) 2-17-13
pharaoh hounds are gorgeous, would love to paint one!!
Pharaoh Hounds!! I want one of these some day.
Pharaoh Hounds animals
I just made a cooler full of compost tea. I use the cooler's spigot to dispense it into the watering can, thirsty plants, drink up! nom nom!
from Apartment Therapy How To Brew Compost Tea
Gardening Plants Outdoors, Brew Compost, Ailing Plants, Super Nutrient Plant, Apartment Therapy, Compost Pile, 2011 02 19 Compost Tea Jpg
We first learned about compost tea during a visit at a local nursery. There, they sold this super-nutrient plant food by the gallon, and it promised to help my ailing plants like no other prescription could do. Now that we know what it's good for, and have our own compost pile in the backyard, we're ready to make our own — it's cheap and easy, and it's like gold for plants!
how to brew compost tea a super-nutrient plant food via @Gilda Anderson Anderson Anderson Locicero Therapy
Brew Compost Tea - Ryan uses an old fish tank pump to add oxygen to our tea
how to brew compost tea a super-nutrient plant food via @Apartment Therapy
How to brew compost tea (helps ailing plants!!)
How To Brew Compost Tea via @Apartment Therapy
Compost Tea for Plant Food
How to "brew" compost tea
love the size of this pool.

value: This website is an image sharing and social media service designed to enable saving and discovery of information  on the internet using images, and on a smaller scale, animated GIFs and videos, in the form of pinboards. The site was created by Ben Silbermann, Paul Sciarra, and Evan Sharp, and had over 478 million global monthly active users as of March 2021.


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text:
by saisureshnaidu
Practical setup of power electronic...
by SHOEBSHAH
POWER ELECTRONICS LAB MANUAL FOR IV SEMESTER B.E (EC / TC / ML) (For private circulation only) VISVESVARAYA TECHNOLOGICAL UNIVERSITY Name :…………………………………………… Reg no :……………………………………………DEPARTMENT OF ELECTRONICS & COMMUNICATIONSRI SIDDHARTHA INSTITUTE OF TECHNOLOGY MARLUR, TUMKUR-572105
Power Electronics Lab manual SSIT CONTENTS Experiment No Page. No1. SCR Characteristics 32. TRIAC Characteristics 93. MOSFET Characteristics 154. IGBT Characteristics 175. RC Triggering Circuit – HWR & FWR 196. UJT Triggering of SCR 237. (LC Commutation Circuit) Oscillation Chopper Circuit 298. UJT Triggering of SCR – HWR & FWR 339. Digital Firing Circuit 3910. AC Voltage control by using TRIAC & DIAC 4111. Single Phase FWR 4512. Impulse Commutated Chopper 4913. Speed control of a 1  Induction motor 5114. Speed Control of Universal motor 5315. Series Inverter 5516. Parallel Inverter 57 Question bank 58 Viva questions 59 Data sheets 64 -1-
Power Electronics Lab manual SSIT Circuit Diagram: - IK ∧ /IW 1K ∧ /1WIdeal Graph: - IL>IH IL > IH IL IH Base Diagrams of 2N3669/70 & TY604: - -2-
Power Electronics Lab manual SSITExperiment No: 1 DATE: __/__/____ S.C.R. CharacteristicsAim: - To study the V-I characteristics of S.C.R. and determine the Break overvoltage, on state resistance Holding current. & Latching currentApparatus required: -SCR – TY604, Power Supplies, Wattage Resistors, Ammeter, Voltmeter, etc.,Procedure: - 1. Connections are made as shown in the circuit diagram. 2. The value of gate current IG, is set to convenient value by adjusting VGG. 3. By varying the anode- cathode supply voltage VAA gradually in step-by- step, note down the corresponding values of VAK & IA. Note down VAK & IA at the instant of firing of SCR and after firing (by reducing the voltmeter ranges and in creasing the ammeter ranges) then increase the supply voltage VAA. Note down corresponding values of VAK & IA. 4. The point at which SCR fires, gives the value of break over voltage VBO. 5. A graph of VAK V/S IA is to be plotted. 6. The on state resistance can be calculated from the graph by using a formula. 7. The gate supply voltage VGG is to be switched off 8. Observe the ammeter reading by reducing the anode-cathode supply voltage VAA. The point at which the ammeter reading suddenly goes to zero gives the value of Holding Current IH. 9. Steps No.2, 3, 4, 5, 6, 7, 8 are repeated for another value of the gate current IG. -3-
Power Electronics Lab manual SSITDesigning Equations:- Wkt, Vaa = Ia R L + VscrLet Ia = 300mA Vaa − Vscr Vscr = 1v RL = Vaa = 30v Ia 30− 1 = 96.66∧ ≅ 100∧ RL = 300⋅10− 3Wattage:- Power in watts = I2RL = (300x10-3)2x100 = 9 watts (select 20 watts) ∴Λοαδ resistor = RL = 100Ω, 20wattsGate Resistance (Rg):- Wkt, Vgg = Ig R g + VgtLet Ig = 15mA Vgg − Vgt Vgt = 1v Rg = Vgg = 15v Ig 15 − 1 Rg = = 933∧ ≅ 1X ∧ 15 ⋅10−3Wattage:- Power in watts = I2Rg = (15x10-3)2x103 = 0.225w (select 1 watt) ∴Γατε resistor = Rg = 1KΩ, 1 watts Note: - Follow the same design procedure for TRIAC connection sting Latching Current -4-
Power Electronics Lab manual SSITAlternate Method: - 1. Connections are made as shown in the circuit diagram 2. Adjust the value of Ig to zero or some minimum value 3. By varying the voltage Vak from 0 to 10 volts with a step of 2 volts, note down corresponding values of Ia 4. Now apply the gate voltage gradually, until SCR fires, then note down the values of Ig and also the values of Ia and Vak 5. Increase Vaa to some value and note down Ia and Vak 6. Reduce gate voltage to zero, observe ammeter reading by reducing Vaa which gives the values of Ih (holding current) at the point at which, current suddenly drops to zero 7. Repeat the steps 2, 3, 4, 5 & 6 for different values of break over voltage 8. Plot a graph of Vak v/s Ia 9. The on state resistance can be calculated from the graph by using formula, ⊗VAK RON - STATE = ∧ ⊗I A -5-
Power Electronics Lab manual SSITTabular column: - Ig = mA Ig = mASl.No VAK Volts IA Α/µΑ/Α Sl.No VAK Volts IA Α/µΑ/Α -6-
Power Electronics Lab manual SSIT Procedure (Latching current) 1. connections one made as shown in the circuit diagram 2. Set Vgg at 7 volts 3. Set Vaa at particular value, observe Ia, by operating the switch (on & off). if in goes to zero after opening of the switch, indicates Ia < IL 4. Repeat step 3 such that the current Ia should not go to zero after opening of the switch. Then Ia gives the value of IL. Viva questions: - 1. Explain the working operation of VI characteristics of S.C.R. 2. Define Holding current, Latching current on state resistance, Break down voltage 3. Explain the working operation of S.C.R. characteristics by using two transistor analogy 4. Write an expression for anode current 5. Mention the applications of S.C.R.? ………………………….…………………….. Signature of the staff with date -7-
Power Electronics Lab manual SSITCIRCUIT DIAGRAM: - 1 K ∧ /1W 1 K ∧ /1W 1 K ∧ /1W 1 K ∧ /1W -8-
Power Electronics Lab manual SSITExperiment No: 2 DATE: __/__/____ TRIAC CharacteristicsAim: - To study the v-1 characteristics of a TRIAC in both directions and also indifferent (1, 2, 3 & 4) modes op operation and determine break over voltages,holding current, latching current and comment on sensitivities.Apparatus required: -TRIAC – BT 136, power supplies, wattage resistors, ammeter, voltmeter, etc.,Procedure: -I mode 1. Connections are made as shown in the circuit diagram (a) 2. The value of gate current ig is set to convenient value by adjusting vgg. 3. By varying the supply voltage Vm gradually in step-by-step, note down the corresponding values of Vmt2t1 and i1. Note down Vmt2t1 and i1 at the instant of firing of TRIAC and after firing (by reducing the voltmeter ranges and increasing the ammeter ranges) then increase the supply voltage Vmt2mt1 and i1. 4. The point at which TRIAC fires gives the value of break over voltage vbo1 5. A graph of vmt2t1 v/s i1 is to be plotted. 6. The gates supply voltage. Vgg is to be switched off 7. Observe the am meter reading by reducing the supply voltage vmt. The point at which the ammeter reading suddenly goes to zero gives the value of holding current ih.II mode: - 1. Connections are made as shown in the circuit diagram (b) 2. The gate current is set as same value as in i-mode 3. Repeat the step no. s 3, 4, 5, 6, & 7 of I-mode -9-
Power Electronics Lab manual SSITCharacteristic curve: -Normal MethodAlternate Method - 10 -
Power Electronics Lab manual SSITIII mode 1. Connections are mode as shown in the circuit diagram (c). 2. Step no. s 2, 3, 4, 5, 6, & 7 are to be repeated as in i-mode.IV mode 1. Connections are mode as shown in the circuit diagram (d) 2. Repeat the step no. s 2, 3, 4, 5, 6, & 7 of i-mode.Alternate Method: - 1. Connections are made as shown in the circuit diagram 2. Adjust the value of Ig to zero or some minimum value 3. By varying the voltage Vmt2mt1 from 0 to 10 volts with a step of 2 volts, note down corresponding values of I1 4. Now apply the gate voltage gradually, until SCR fires, then note down the values of Ig and also the values of I1 and Vmt2mt1. 5. Increase Vm to some value and note down I1 and Vmt2mt1. 6. Reduce gate voltage to zero, observe ammeter reading by reducing Vm which gives the values of Ih (holding current) at the point at which, current suddenly drops to zero 7. Repeat the steps 2, 3, 4, 5 & 6 for different values of break over voltages 8. Plot a graph of Vmt1mt2 v/s I1 9. Repeat the steps 1, 2, 3, 4, 5, 6 & 7 for different modes 10.Compare sensitivity of TRIAC and comment on sensitivities. 11.Refer same design procedure for selection of RL and Rg as that of SCR. 12.Follow the same procedure as that of SCR experiment to find latching current. - 11 -
Power Electronics Lab manual SSITTabular column: -I-mode II-mode ig= ma Ig= ma Sl.no VTRIAC volts ITRIAC ma Sl.no VTRIAC volts ITRIAC maIII-mode IV-mode ig= ma Ig= ma Sl.no VTRIAC volts ITRIAC ma Sl.no VTRIAC volts ITRIAC maBase diagram of BT136: - 12 -
Power Electronics Lab manual SSITViva questions: - 1. Explain the different working modes of operations of a TRIAC? 2. Why i-mode is more sensitive among all modes? 3. What are the applications of TRIAC 4. Compare SCR, TRIAC & DIAC 5. Why I & II modes are operating in Ist quadrant and III & IV modes are operating in IIIrd quadrant? - 13 -
Power Electronics Lab manual SSIT ………………………….…………………….. Signature of the staff with dateCircuit Diagram: -Ideal Graphs: - Drain Characteristics Transconductance CharacteristicsTabularColumnVGS = VGS = VDS = VDS =VDS(V) ID(mA) VDS(V) ID(mA) VGS(V) ID(mA) VGS(V) ID(mA) - 14 -
Power Electronics Lab manual SSITExperiment No: 3 DATE: __/__/____ MOSFET CharacteristicsAim: - To study the characteristics of MOSFETApparatus required: -MOSFET-IRF740, Power Supplies, Wattage Resistors, Ammeter, Voltmeter, etc.,Procedure: -Drain Characteristics1. Connections are made as shown in the circuit diagram.2. Adjust the value of VGS slightly more than threshold voltage Vth3. By varying V1, note down ID & VDS and are tabulated in the tabular column4. Repeat the experiment for different values of VGS and note down ID v/s VDS5. Draw the graph of ID v/s VDS for different values of VGS.Transconductance Characteristics1. Connections are made as shown in the circuit diagram.2. Initially keep V1 and V2 zero.3. Set VDS = say 0.6 V4. Slowly vary V2 (VGE) with a step of 0.5 volts, note down corresponding ID and VDS readings for every 0.5v and are tabulated in the tabular column - 15 -
Power Electronics Lab manual SSIT5. Repeat the experiment for different values of VDS & draw the graph of ID v/s VGS6. Plot the graph of VGS v/s ID …………..…………………………………….. Signature of the staff-in-chargeCircuit Diagram: -Ideal Graphs: - Collector Transconductance Characteristics CharacteristicsTabularColumn - 16 -
Power Electronics Lab manual SSITVGE = VGE = VCE = VCE =VCE(V) IC(mA) VCE(V) IC(mA) VGE(V) IC(mA) VGE(V) IC(mA)Experiment No: 4 DATE: __/__/____ IGBT CharacteristicsAim: - To study the characteristics of IGBTApparatus required: -IGBT-IRGBC 20S, Power Supplies, Wattage Resistors, Ammeter, Voltmeter, etc.,Procedure: -Collector Characteristics1. Connections are mode as shown in the circuit diagram.2. Initially set V2 to VGE1 = 5v (slightly more than threshold voltage)3. Slowly vary V1 and note down IC and VCE4. For particular value of VGE there is pinch off voltage (VP) between collector and emitter5. Repeat the experiment for different values of VGE and note down IC v/s VCE6. Draw the graph of IC v/s VCE for different values of VGE.Transconductance Characteristics1. Connections are mode as shown in the circuit diagram.2. Initially keep V1 and V2 at zero.3. Set VCE1 = say 0.8 v - 17 -
Power Electronics Lab manual SSIT4. Slowly vary V2 (VGE) and note down IC and VGE readings for every 0.5v and enter tabular column5. Repeat the experiment for different values of VCE and draw the graph of IC v/s VGE …………………..…………………………….. Signature of the staff-in-charge Half Wave Rectifier using RC TriggeringCircuit diagram:- RWaveforms:- - 18 -
Power Electronics Lab manual SSITGraph: -Experiment No: 5 DATE: __/__/____ RC Triggering Circuit – HWR & FWRAIM: - To study the performance & waveforms of HWR & FWR by using RCtriggering CircuitAPPARATUS REQUIRED: - Transformer, SCR – TY604, BY127, Resistor, Capacitor, Ammeter,VoltmeterPROCEDURE: - - 19 -
Power Electronics Lab manual SSITHalf Wave Rectifier 1. Connections are made as shown in the circuit diagram 2. By varying a resistance R gradually in step by step, note down the corresponding values of Vn & Vm from CRO and Vodc from the DC voltmeter. The readings are tabulated in the tabular column. 3. If the firing angle ranges from 0 to 90O, then the firing angle 〈 is calculated by using a formula α = sin-1  n  in degrees. V  V  m 4. The conduction angle ® is calculated by using a formula, ® = 180 - 〈. 5. The current and power is calculated by Vodc V2 Iodc = A & Podc = odc Watts respectively. R R 6. A graph of Vo v/s 〈, Vo v/s ®, Io v/s 〈, Io v/s ®, Podc v/s 〈, Podc v/s ® are to be plotted. 7. Compare practical output voltage with theoretical output voltage, Vm (1 + cosα) volts Voth = where Vm = 2Vrms 2πFull Wave Rectifier 1. Repeat the above said procedure for full wave rectifier. Vm Voth = (1 + cosα) volts where Vm = 2Vrms π Full Wave Rectifier using RC TriggeringCircuit diagram:- - 20 -
Power Electronics Lab manual SSITWaveforms:-Tabular Columns:-Half Wave RectifierSl. No. Vn Vm (α<90O) (α>90O) Vodc Voth - 21 -
Power Electronics Lab manual SSIT  V  V  α = sin-1  n  α = 180 − sin-1  n  m   V  m V Full Wave Rectifier (α<90O) (α>90O)Sl. No. Vn Vm α = sin-1   V n  α = 180 − sin-1   V  Vodc Voth n   V  m  m V Viva Questions: - 1. Explain the working operation of the circuit? 2. What are the limitations of R triggering circuit? 3. What are the limitations of RC triggering circuit? 4. Mention different methods of triggering SCR? 5. Why gate triggering is preferred? ……………………………….………………… Signature of the staff-in-charge - 22 -
Power Electronics Lab manual SSITCIRCUIT DIAGRAM: -Base Diagrams: - SCR-TY604 UJT: -2N2646 Diode: - BY127 Pulse Transformer - 23 -
Power Electronics Lab manual SSITExperiment No: 6 DATE: __/__/____ U. J. T. Triggering of S. C. RAIM: - To study the performance & waveforms of U.J.T triggering of S.C.R.APPARATUS REQUIRED: -SCR-TY604, Power supplies, Wattage Resistors, Ammeter, Voltmeter, UJT-2N2646, Pulse Transformer, etc.,PROCEDURE: - 1. Connections are mode as shown in the circuit diagram 2. By varying a resistance R gradually in step by step, note down the corresponding values of Vn & Vm from CRO and VOdc from D.C voltmeter. The readings are tabulated in the tabular column. 3. If firing angle ranges from 0 to 900, then firing angle can be calculated from  V 〈 = Sin −1  n  in deg rees  V   m If firing angle ranges from 900 to 1800, then firing angle can be calculated by using a formula, 〈 = 180− Sin−1   Vn   in degrees   Vm  4. The conduction angle ® can be calculated by using a formula, ®= 180 - 〈 5. The current & power is calculated by Vdc Idc = Amps R Vdc2 Pdc = Watts respectively R 6. A graph of Vdc v/s 〈, Vdc v/s ®, Idc v/s 〈, Idc v/s ®, Pdc v/s 〈 , and Pdc v/s ® are to be plotted on a graph sheet. - 24 -
Power Electronics Lab manual SSIT IDEAL WAVEFORMS: - Tabular Column: - FROM C.R.O 0 TO 900 900 TO 1800 Pdc = VDC Idc =Sl. (Vload) Vdc2/R VothNo ®= Vdc/R A volts Vn Vm ο ο Watts α = Sin−1  nV   ®=180−〈 Vn Vm α = 180 − Sin−1 Vn   180-α volts volts  m   V volts volts  m  V  - 25 -
Power Electronics Lab manual SSIT 7. For given frequency, the value of R can be calculated by using a formula, 1 T = 2.303RC.log10 1− T R= ∧ 1 2.303C.log10 1− When C = 0.1 mF & N = Intrinsic stand off ratio = 0.67 8. This value of R is set in the circuit, Step No S 3. 4. 5. & 6. are repeated and waveforms are observed at different points as shown. Vm 9. Compare Voth with VoPractical where Voth = [1 + cos 〈]VIVA QUESTIONS: - 1. Explain the working operation of U.J.T. triggering circuit waveforms? 2. Why U.J.T. Triggering circuit is superior when compared to R & RC triggering circuit? 3. What is the use of pulse transformer? 4. Explain the design part of UJT? 5. Write equivalent circuit of UJT and show that Vpeak = Vemitter = V©+ηVBB. 6. Why do we require turn-on circuits for thyristors? 7. Why do we require turn-off circuits for thyristors? 8. Comment on Forced & Natural Commutation techniques. …………………………………………………. Signature of the staff-in-charge - 26 -
Power Electronics Lab manual SSIT - 27 -
Power Electronics Lab manual SSIT - 28 -
Power Electronics Lab manual SSITCIRCUIT DIAGRAM: - R1IDEAL WAVEFORMS: -IDEAL GRAPH: - ` - 29 -
Power Electronics Lab manual SSITExperiment No: 7 DATE: __/__/____ Oscillation Chopper Circuit AIM: - a) To convert variable D.C. voltage from a fixed D.C. input voltage. b) Plot a graph of VDCOUT v/s Duty cycle (K)APPARATUS REQUIRED: -SCR-TY604, UJT-242646, Pulse Transformer, Power supplies, Wattage resistor,Ammeter, Voltmeter, etc.,PROCEDURE: -A. Variable Frequency Operation 1. Connections are mode as shown in the circuit diagram. 2. The input D.C. voltage VDC is set as convenient value say 20 V 3. Select proper values of L, for a given duty cycle C is calculated so that TON is constant. 4. By varying the variable resistor R1 in step-by-step gradually, note down TON and T from CRO and VO or VDCout from D.C voltmeter. 5. The theoretical Ton and theoretical T are to be calculated by using a formula. 1 TONth = ∠ LC Tth = 2.303R 1C1.log10 1− Where  = Intrinsic stand off ratio = 0.67 6. The theoretical output voltage VO or VDCOUT-th are to be calculated using formula, TONth TONCRO VOth = VDCoutth = ⋅ VDC VOCRO = VDCoutCRO = ⋅ VDC Tth TCRO 7. All observations and calculations are tabulated in a tabular column. 8. Compare Voth, VoCRO & VO d.c.voltmeter 9. Plot a graph of Vodc v/s duty cycle (k)Turn-off Circuit Design: - Ipeak = V C Where Ipeak = 2IO L LC Toff = Toff = Device turn off time 2 - 30 -
Power Electronics Lab manual SSIT Tabular Column:- (A) VDC VOth = VOCRO = R1 C1 L C TONth = Tth = 2.303 VOSl.No Volts 1 TONCRO TCRO TON CRO ∧ Φ H Φ ∠ LC RC.log10 ⋅ VDC D.C.Voltmeter TCRO Tabular Column:- (B) VDC TONth = Tth = 2.303 Duty cycle TON R1 C1 L C Sl.No Volts K= VO = ⋅ VDC ∧ Φ H Φ ∠ LC RC.log10 T T Let I O = 100 mA I peak = V I peak = 200 mA L V 20 l V = 20 volts T off = 50  s 2 LC  2Toff   2 ⋅ 50 ⋅ 10 −6 Toff =  = 1 ⋅ 10 − 9 2     solving1 & 2weget −9 We know that C = 1 ⋅ 10 -4 )L ∴L = 1 ⋅ 10 -4 = 3.16 mH ∴C = 1 ⋅ 10 -4
- 31 - TON th ⋅ VDC 1− Tth 1 TON 1− C L = 1 1 2  ∴LC =   =   ( 1 ⋅ 10( -4 − 3 −7
Power Electronics Lab manual SSITFor successful commutation, turn off time of the circuit should be greater thanturn off time of the device.Select C = 1μF and L = 3mH. LC∴Χιρχυιτ turn off time = = 1 ⋅ 10 −6 ⋅ 3 ⋅ 10 −3 = 86s 2 2∴Χιρχυιτ turn off time > turn off time of the device i.e., 86μs > 50μsB. Fixed Frequency Operation1. The value of variable resistor R1 is set at some value is T is fixed TON2. By varying L at different values, calculate the duty cycle K = Where T 1 TON = ∠ LC and T = 2.303RC.log10 1− th Note down the corresponding o/p D.C. Voltage VDCOUT from D.C.Voltmeter3. TON th TON CRO VO = VDCout = th th ⋅VDC VO = VDCout CRO CRO = ⋅ VDC Tth TCRO4. Plot a graph of VDCOUT v/s Duty cycle (K)VIVA QUESTIONS: - 1. Explain the working operation of oscillation chopper circuit? 2. What type of commutation circuit is employed in this circuit? Why it is necessary? 3. Why UJT triggering is preferred? 4. Explain the working function of each component? 5. Explain the different types of commutation circuit Note:- for T = 10 ms, K = 30% means TON = 0.3 T T = TON + TOFF K = 50% means TON = 0.5 T ……………………………….………………... Signature of the staff-in-charge - 32 -
Power Electronics Lab manual SSITCIRCUIT DIAGRAM: -Half Wave RectifierFull Wave Rectifier - 33 -
Power Electronics Lab manual SSITExperiment No: 8 DATE: __/__/____ U. J. T. Triggering for HWR & FWRAIM: - To study the performance & waveforms of U.J.T triggering of S.C.R.APPARATUS REQUIRED: -SCR-TY604, Power supplies, Wattage Resistors, Ammeter, Voltmeter, UJT-2N2646, Pulse Transformer, etc.,PROCEDURE: - 1. Connections are mode as shown in the circuit diagram 2. By varying a resistance R gradually in step by step, note down the corresponding values of Vn & Vm from CRO and Vdc from D.C voltmeter. The readings are tabulated in the tabular column. 3. If firing angle ranges from 0 to 900, then firing angle can be calculated from 〈 = Sin −1  n V  in deg rees .If firing angle ranges from 900 to 1800,   V   m  then firing angle can be calculated by using a formula, 〈 = 180 − Sin −1   V  n in deg rees   V   m  4. The conduction angle ® can be calculated by using a formula,β= 180 - 〈 5. The current & power is calculated by Vdc2 Idc = dc Amps V Pdc = Watts respectively R R 6. A graph of Vdc v/s 〈, Vdc v/s ®, Idc v/s 〈, Idc v/s ®, Pdc v/s 〈 , and Pdc v/s ® are to be plotted on a graph sheet. - 34 -
Power Electronics Lab manual SSITIDEAL WAVEFORMS: - - 35 -
Power Electronics Lab manual SSIT 7. For given frequency, the value of R can be calculated by using a formula, 1 T = 2.303RC.log10 1− T R= ∧ 1 2.303C.log10 1− When C = 0.1 mF & N = Intrinsic stand off ratio = 0.67 8. This value of R is set in the circuit, Step No S 3. 4. 5. & 6. are repeated and waveforms are observed at different points as shown. 9. The practical o/p voltage (Vo meter) is compared with Voth For HWR Voth = Vm (1 + cos〈 ) voltswhereVm = 2Vin rms , 2 For FWR Voth = V (1 + cos〈 ) volts , mGraph: - - 36 -
Power Electronics Lab manual SSITTabular Column:- a) Half wave switches FROM C.R.O 0 TO 900 900 TO 1800 Idc = Pdc = VDCSl.No (Vload) Vdc/R Vdc2/R 〈 = 180− volts Vn Vm  V ο ®=180− Vn Vm ®=180− A Watts ο α = Sin−1   n   volts volts  Vm  〈 volts volts −1V 〈 Sin  n    Vm Full wave switches FROM C.R.O 0 TO 900 900 TO 1800 Idc = Pdc = VDCSl. (Vload) Vdc/R Vdc2/RNo 〈 = 180− volts Vn Vm  ®=180− Vn Vm ®=180− A Watts  〈 = Sin−1   V  n volts volts  m   V 〈 volts volts Sin−1  V  n 〈  V  mBase Diagrams: - SCR-TY604 UJT: -2N2646 Diode: - BY127 - 37 -
Power Electronics Lab manual SSITVIVA QUESTIONS: - 1. Explain the working operation of U.J.T. triggering circuit waveforms? 2. Why U.J.T. Triggering circuit is superior when compared to R & RC triggering circuit? 3. What is the use of pulse transformer? 4. Explain the design part of UJT? 5. Write equivalent circuit of UJT and show that Vpeak = Vemitter = V©+ηVBB. 6. Why do we require turn-on circuits for thyristors? 7. Why do we require turn-off circuits for thyristors? 8. Comment on Forced & Natural Commutation techniques. - 38 -
Power Electronics Lab manual SSIT …………………………………………………. Signature of the staff-in-chargeCircuit Diagram:Wave form:-Graph:-Tabular Column:- - 39 -
Power Electronics Lab manual SSIT Sl. No. Firing Angle (α) VODCExperiment No: 9 DATE: __/__/____ Digital Firing CircuitAim: - To demonstrate digital firing circuit to turn on SCR (HW) for R-Load and toplot VODC v/s 〈.Apparatus required: - Digital Firing Module, SCR-TYN604, Resistor, etc.,Procedure: - 1. Connections are made as shown in the circuit diagram. 2. Firing angle 〈 is varied in steps gradually, note down corresponding values of VODC (DC voltmeter reading) and tabulate. 3. A graph of 〈 v/s VODC is plotted.Result: - Digital Firing Circuit to turn on SCR is studied and a graph of 〈 v/s VODC is plotted. - 40 -
Power Electronics Lab manual SSIT ………………………….…………………….. Signature of the staff with dateCIRCUIT DIAGRAM: - - 41 -
Power Electronics Lab manual SSITExperiment No: 10 DATE: __/__/____ AC Voltage Control by using TRIAC-DIAC CombinationAIM: - 1. To study the AC voltage control by using TRIAC-DIAC combinationAPPARATUS REQUIRED: -TRIAC, DIAC, supply voltage, wattage resistors, Ammeter, Voltmeter, etc,.PROCEDURE: -A. 1. Connections are mode as shown in the circuit diagram (a) 2. By varying the variable resistance R1 in step by step, observe the variation of intensity of light.B. 1. Connections are mode as shown in the circuit diagram (b) 2. By varying the resistance R, in step-by-step note down the corresponding vales of Vn & Vm from C.R.O. and Va.c from A.C. voltmeter the readings are tabulated in the tabular column - 42 -
Power Electronics Lab manual SSIT 3. If delay angle ranges from 0 To 900, then firing angle can be calculated  V from α = Sin −1  n  in degrees . If firing angle ranges from 900 To 1800 then m  V can be calculated by using a formula, α = 180 − Sin−1  in  Vn  degrees    Vm  4. The conduction angle B can be calculated by using a formula, ®= 180 - 〈 in degrees 5. The current can be calculated by Iac = Vac R 6. A graph of Iac v/s 〈, Vac or load voltage v/s 〈 are to be plotted 1 −〈+ sin 2〈  7. Compare Voeter with Voth where Voth = Vin rms   2  Tabular Column: - FROM C.R.O Idc = Vin 0 TO 900 900 TO 1800 VDC Volt SpeedSl. Vdc/ (Vload)No R rpm L = 180 - volts s  Vn Vm 〈 = Sin−1    n V ®=180− Vn Vm  ®=180− A  m 〈 〈 volts volts  V volts volts Sin−1  n  V    Vm   Waveforms:- - 43 -
Power Electronics Lab manual SSITVIVA QUESTIONS: - 1. Explain the features of TRIAC? 2. Explain the working operation of illumination control & various voltage output waveforms by using TRIAC? 3. Compare S.C.R, DIAC & TRIAC? 4. What is universal motor? Comment on the different graphs of this experiment? 5. 6. Mention the applications of TRIAC? - 44 -
Power Electronics Lab manual SSIT ……………………………………………….. Signature of the staff with dateCIRCUIT DIAGRAM: - (a) With R-load (Resistive load) - 45 -
Power Electronics Lab manual SSITGRAPHS: -Experiment No: 11 DATE: __/__/____ Single Phase Full Wave Controlled RectifierAIM: - 1. To study the performance and waveforms of full wave controlled rectifier with Resistance load and Inductive load 2. Plot a graph of VO v/s for R-loadAPPARATUS REQUIRED: -SCR-TY604, Power supplies, Wattage Resistors, Ammeter, Voltmeter, UJT-2N2646, BY127, Inductor, Pulse Transformer, etc.,PROCEDURE: - 1. Connections are made as shown in the circuit diagram for resistive load. - 46 -
Power Electronics Lab manual SSIT 2. By varying a variable resistor R in step-by-step gradually. Note down corresponding values of VN, VM, from C.R.O. and VO or Vload or VDC from d.c.voltmeter for resistive load, the readings are tabulated in the tabular column 3. If 〈 varies from 0 To 900, then firing angle can be calculated from  V  〈 = Sin −1  n  in deg rees  V   m  If 〈 varies from 900 to 1800 then 〈 is 〈 = 180 − Sin −1   V  n  in deg rees  V   m  4. The conduction angle ®= 180 - 〈 in degrees is calculated for each value of 〈 5. Plot a graph of VDC or Vload or VO v/s firing angle 〈 6. Observe the waveforms at different points as shown and waveforms are traced on tracing paper. 7. For Inductance load repeat step no. s 1,2,3,4,5 & 6. - 47 -
Power Electronics Lab manual SSITWAVEFORMS: -TABULAR COLUMN: - (a) For Resistive load From CRO 00 – 900 900 – 1800 VO or VDCSl.No or VLOAD VN VM 〈 = Sin−1  n V   O ®=180 - VN VM 〈 = 180 − Sin −1   V  O ®=180 - volts n  volts volts  m  V 〈 volts volts  V m   〈 - 48 -
Power Electronics Lab manual SSITb) Inductive load: From CRO 00 – 900 900 – 1800 VO or VDCSl.No or VLOAD VN VM 〈 = Sin−1  n  ®=180 - VN VM 〈 = 180 − Sin −1  n ®=180 - volts volts volts  m  〈 volts volts  m 〈C) R L with Free wheeling diode From CRO 00 – 900 900 – 1800 VO or VDCSl.No or VLOAD VN VM  V ®=180 - VN VM  V ®=180 - volts volts volts 〈 = Sin−1  n  〈 v 〈 = 180 − Sin −1  n  〈 o l t s v o l t sVIVA QUESTIONS: - 1. Explain the performance and working operation of single-phase full controlled rectifier with relevant waveforms for Resistive load, Inductive load. 2. Compare H.C.R with F.C.R 3. In cyclo-converter, why H.C.R with Inductive load cannot be implemented ……………………………………………….. Signature of the staff with date
- 49 - O O V  V   V   V   O O    Vm   Vm 
Power Electronics Lab manual SSITImpulse Commutated Chopper: VDCWave forms:-Graph:- - 50 -
Power Electronics Lab manual SSITExperiment No: 12 DATE: __/__/____ Impulse Commutated ChopperAim: - To study the performance of voltage commutated chopper for constantfrequency operations.Apparatus required: - Module, SCRs, Diodes, inductor, capacitors, etc.,Procedure: - 1. Connections are made as shown in the circuit diagram. 2. Input DC voltage is set to convenient value (10v to 25v). 3. By varying duty cycle knob of triggering circuit module step by step gradually note down corresponding Ton and T from the CRO and VO from DC voltmeter and tabulate. Ton 4. Duty cycle ‘K’ is calculated by usingK = T . 5. A graph of VO v/s K is plotted. 6. Observe load and device voltage waveforms.Tabular Column: - Sl. No. Duty Cycle knobs TON cro TCRO TON Vo (V) K= T ………………………….…………………….. Signature of the staff with date - 51 -
Power Electronics Lab manual SSITSingle Phase Induction Motor:Graph:-Tabular Column:- Sl. No. Firing Angle (α) Speed in RPM - 52 -
Power Electronics Lab manual SSITExperiment No: 13 DATE: __/__/____ Speed Control of Single Phase Induction MotorAim: - To study speed control of Induction motor and plot speed v/s 〈.Apparatus required: - Module, TRIAC, Induction Motor, etc.,Procedure: - 1. Connections are made as shown in the circuit diagram. 2. Firing angle 〈 is varied in steps gradually, note down corresponding speed of the induction motor using Tachometer and tabulate. 3. A graph of 〈 v/s speed is plotted.Result: - Speed control of Induction Motor is studied and a graph of 〈 v/s speed is plotted. ………………………….…………………….. Signature of the staff with date - 53 -
Power Electronics Lab manual SSITUniversal Motor (DC):Universal Motor (AC):Graph:-Tabular Column:- AC Motor DC MotorSl. Firing Angle Speed in Sl. Firing Angle Speed inNo. (α) RPM No. (α) RPM - 54 -
Power Electronics Lab manual SSITExperiment No: 14 DATE: __/__/____ Speed Control of Universal MotorAim: - To study speed control of Universal motor and plot speed v/s 〈.Apparatus required: - Module, TRIAC-BT136, Universal Motor, Diode-IN4001 etc.,Procedure: -DC Motor: - 1. Connections are made as shown in the circuit diagram. 2. Firing angle 〈 is varied in steps gradually, note down corresponding speed of the induction motor using Tachometer and tabulate. 3. A graph of 〈 v/s speed is plotted.AC Motor: - 1. Above procedure is repeated for AC Motor.Result: - Speed control of Universal Motor is studied and a graph of 〈 v/s speed is plotted. ………………………….…………………….. Signature of the staff with date - 55 -
Power Electronics Lab manual SSITSeries InverterWave forms:- - 56 -
Power Electronics Lab manual SSITExperiment No: 15 DATE: __/__/____ Series InverterAim: - To obtain variable AC from DC ripple input.Apparatus required: - Module, SCRs, Diodes, inductor, capacitors, etc.,Procedure: - 1. To begin with switch on the power supply to the firing circuit check that trigger pulses by varying the frequency. 2. Connections are made as shown in the circuit diagram. 3. Now connect trigger outputs from the firing circuits to gate and cathode of SCRs T1 & T2. 4. Connect DC input from a 30v/2A regulated power supply and switch on the input DC supply. 5. Now apply trigger pulses to SCRs and observe voltage waveform across the load. 6. Measure Vorms & frequency of o/p voltage waveform.Resonance frequency: - 1 1 R2 fr = 2 LC 4L− 2 L=10mH, C = 10μF, R = 20Ω, fth=477Hz, fp=250KHz …………………………….………………….. Signature of the staff with date - 57 -
Power Electronics Lab manual SSITExperiment No: 16 DATE: __/__/____ Parallel Inverter …………………………….………………….. Signature of the staff with date - 58 -
Power Electronics Lab manual SSIT Parallel InverterAim :-To obtain variable AC from DC ripple input.Apparatus required:-Module, SCRs, Diodes, inductor, capacitors, etc,,Procedure:- 1. Connecting are made as shown in the circuit diagram 2. Select values of c = ,L= 3. Set input voltage to 5 volts 4. Apply trigger voltage, observe corresponding output voltage ( ac voltage and wave forms) at load terminal 5. Note down the voltage & frequency of out put wave form 6. The o/p ac voltage is almost equal to the two times of the dc i/p voltage. …………………………….………………….. Signature of the staff with date - 59 -
Power Electronics Lab manual SSIT QUESTION BANK 4TH Semester EC/TC/ML 1. Obtain the VI characteristics of the SCR by conducting a suitable current and hence determine the holding current, forward ON state resistance & break over voltage. 2. Conduct a suitable experiment to obtain VI characteristics of the given three layer bi-directional switch experimentally. Determine the holding current and break over voltage in I and III quadrants and comment on its sensitivity. 3. Conduct a suitable experiment to obtain collector and transfer characteristics of IGBT. 4. Conduct a suitable experiment to obtain drain and transfer characteristics of MOSFET. 5. Conduct an experiment to obtain synchronized triggering pulses to turn ON SCR in full wave rectifier with resistive load. Show load voltage and triggering pulse waveform. Plot average DC voltage v/s delay angle. 6. Conduct an experiment to obtain synchronized triggering pulses to turn ON SCR in full wave rectifier with resistive and inductive load. Show load voltage and triggering pulse waveform. Plot average DC voltage v/s delay angle. 7. Conduct an experiment on controlled half wave rectifier to vary the DC power fed to load by using RC triggering. Plot o/p voltage v/s firing angle. 8. Conduct an experiment on controlled full wave rectifier to vary the DC power fed to load by using RC triggering. Plot o/p voltage v/s firing angle. 9. Conduct an experiment to control the illumination of incandescent lamp using TRIAC, DIAC combination. Plot the graph of VORMS v/s 〈. 10.Conduct an experiment to produce variable DC o/p voltage (chopper), plot o/p voltage v/s duty cycle for Variable frequency & Fixed Frequency. 11.Conduct an experiment to produce variable DC o/p voltage using voltage commutated chopper, plot o/p voltage v/s duty cycle for Fixed frequency operation. 12.Conduct a suitable experiment to control the speed of Induction motor. Plot speed v/s 〈. 13.Conduct a suitable experiment to control the speed of Universal motor. Plot speed v/s 〈. 14.Conduct a suitable experiment to obtain AC o/p using Series Inverter. 15.Demonstrate the digital firing circuit to turn ON SCR (HW) for R load. Plot VODC v/s 〈 - 60 -
Power Electronics Lab manual SSIT VIVA QUESTIONS OF POWR ELECTRONICS LAB - 61 -
Power Electronics Lab manual SSIT Viva Questions Power Electronics Lab1. What is power electronics?2. Mention the different methods of varying the power?3. What are the advantages of silicon over germanium?4. What is power device?5. Mention different types power devices?6. What is SCR?7. What are the features of SCR?8. What are the features of Diac?9. What is Diac?10. What are the features of diac?11. What are the applications of diac?12. What is Triac?13. What are the applications of Triac?14. What are the applications of Triac?15. What is power MOSFET?16. What is power IGBT?17. What are the applications of MOSFET & IGBT?18. Compare SCR, Diac & Triac?19. Compare MOSFET, BJT & IGBT?20. What is turn of time?21. What is turn off time?22. What is static characteristics?23. What is dynamic Characteristics?24. What are the differences between static & dynamic Characteristics?25. Explain gate characteristics & turn off characteristics of SCR?26. Explain gate characteristics of SCR?27. What is current controlled device?28. What is voltage controlled device?29. Explain o/p & transfer characteristics of MOSFET & IGBT?30. What is the intention of using power device in power control circuit?31. What is power control?32. Why SCR is called as bidirectional an controlled device?33. Why Diac is called as bidirectional an controlled Device?34. Why Triac is called as bidirectional controlled device?35. What is rectifier?36. What is an inverter?37. What is steep down chopper? What is its o/p voltage equation?38. What is step up chopper? What is its o/p voltage equation?39. What is buck boost regulator? What is its o/p voltage equation? - 62 -
Power Electronics Lab manual SSIT40. What is cuck regulator? What is its/ o/p voltage equation? Explain the working operation of single phase controlled half wave rectifier with (a) R load41. (b) RL load (c) RL load with freewheeling diode42. What is an intention of using freewheeling across inductive load in rectifier circuit?43. What is pulse width?44. Why turn off time of the circuit should be greater than turn off time of the device? Explain the working operation of single phase Full wave controlled rectifier with a) R load45. b) RL load c) RL load with freewheeling diode? Explain the working operation of single phase Half controlled bridge rectifier with a) R load46. b) RL load c) RL load with freewheeling diode? Explain the working operation of single phase full controlled bridge rectifier with a) R load47. b) RL load c) RL load with freewheeling diode?48. Define average output voltage, Rms Voltage, peak or maximum voltage? Derive an expression of average output voltage, Rms out voltage of any wave form49. concerned to rectifier, ac voltage controller, chopper?50. What is cyclo converter?51. What is cyclo inverter?52. Why forced commutation circuit is employed in case of cycle inverter?53. What are the advantages of three phase circuit over single phase circuit?54. What is firing angle or delay angle?55. What is conduction period?56. What is the meaning of triggering?57. What are the different types of triggering methods (Can be used to trigger SCR)? What is anode triggering, dv/dt triggering, temperature triggering, light triggering &58. gate triggering?59. Why gate triggering is preferred than other types?60. Mention the different types of gate triggering circuits?61. Explain the working operation of R- triggering circuit?62. Why firing angle in case of R- triggering circuit is limited to 90 degrees?63. Explain the working operation of RC triggering circuit? Explain how firing angle will be extended to more than 90 0 by using RC triggering64. circuit?65. What is Uni-junction transistor (UJT)?66. Write equivalent circuit of UJT? Show that Vpeak = Vp= nVBB+ V diode Where n = intrinsic standoff ratio, V BB =67. applied or base voltage - 63 -
Power Electronics Lab manual SSIT68. Why UJT triggering circuit is superior than R & RC triggering circuit?69. What is UJT relaxation oscillator?70. What is line synchronized UJT triggering circuit?71. Explain the working operation of UJT relaxation oscillator? Explain the working operation of line synchronized UJT triggering circuit with wave72. forms at different points?73. Design of UJT triggering circuit.74. When UJT will conduct?75. How UJT exhibits negative resistance property?76. Why SCR, DIAC, TRIAC are called negative resistance devices?77. Derive an expression of of frequency of UJT triggering pulse?78. What is the function of pulse Transformer? What are the different types of voltage ratings, current ratings & power ratings?79. Explain each term80. Why do we require protection circuits for power devices?81. What is dv/dt rating? How do you protect SCR against high dv/dt rating? Explain82. What is dv/dt rating? How do you protect SCR against high dv/dt rating? Explain83. What is over current? How do you project SCR against over current? Explain84. What is over voltage? How do you lprotect SCR against over voltage? Explain85. How device will be protected against heavy power dissipation?86. Why Triac has 4 modes of operations? Why 1st & 2nd mode of operations are operating in 1st quadrant and 3rd & 4th mode of87. operations are operating 3rd quadrant?88. Why mode (1) is most sensitive among all modes?89. What is commutation? What is commutation circuit?90. Mention the different types of forced commutation circuit? Explain the working operation of each forced commutation circuit with wave forms &91. derivation of designed equations (class A, Class B, class C, Class D, Class E & Class F commutation circuit)92. What is Latching current? What is its significance?93. What is Holding current? What is its significance?94. What is dv/dt Rating? What is its significance?95. What is dual converter? Why full wave bridge controlled bridge rectifier with RL load (not with freewheeling96. diode) is preferred in dual converter than half wave bridge controlled rectifier with RL load (not with freewheeling diode).?97. Why dual converter is called as four quadrant operator?98. What is semi converter?99. What is full converter? Why gate is preferred at base of NPN transistor & not at the base of PNP transistor in100. SCR?101. Derive an expression of anode current (SCR current)?102. Explain the working operation of SCR with two transistor analogy? - 64 -
Power Electronics Lab manual SSIT Explain the working operation of each practical power electronics experiments with103. circuit diagram, wave forms & designed equations?104. Why output voltage is more at lesser value of firing angle?105. What are the differences between uncontrolled output & controlled output?106. How do you design zener voltage regulator? How do you select (design) the value of gate resistor and load resistor concerned to107. SCR experiment?108. How do you check SCR, Triac, Diac, Diode, Zener diode, wires by using ohm meter?109. How do you check an ammeter, voltmeter & power supply?110. Why load resistor has higher wattage? What is series inverter? Mention the advantages, disadvantages & applications of111. series inverter? Explain its working operation?112. What is parallel inverter? Explain its working operation? What is continuous mode & discontinuous mode of operations concerned to rectifier113. with (a). RL load (b) RL load with freewheeling diode. Input voltage = device voltage + output voltage.114. Prove above words115. What is blocking state or region?116. What is forward blocking & reverse blocking?117. What is reverse recovery time?118. What is gate pulse?119. Why gate pulses are preferred than continuous gate voltage?120. S.T. turn on time =td + tr+ ts121. S.T. turn off time = trr + tgr122. How do you design gate pulse width?123. What is snubber circuit? How do you design snubber?124. What is heat sink? Its purpose is what?125. What is circuit breaker & fuse? Why these are used in power circuit?126. What is ac voltage controller? Mention different types? What are its applications? Explain the working operation of (a). on & off AC voltage controller127. (b). uni directional or Half wave controller (c) . Bidirectional or Full wave AC voltage controller with R load & RL load with wave forms, with equations? Why continuous gate pulses are applied to full wave ac voltage controller with RL load128. circuit?129. Explain the working operation of static on load tap changer?130. Why negative gate voltage should not be applied to gate of SCR?131. Write symbols, static characteristics of all power devices concerned to syllabus?132. Name different current controlled power devices?133. Name different voltage controlled power devices?134. What is I2t rating? - 65 -
Power Electronics Lab manual SSIT Data Sheets - 66 -
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CBS Evening News With Katie Couric : WUSA : September 1, 2010 6:30pm-7:00pm EDT : Free Borrow & Streaming : Internet Archive
tv CBS Evening News With Katie Couric CBS September 1, 2010 6:30pm-7:00pm EDT
suddenly everything changes and it must put everything in perspective. >> am a graduate student at the university of maryland so i was supposed to go to class and i'm calling my friends and telling them turn on the news, i'm stuck, this is why, you can please let people know and of course my mom was worried. [ stand by for change in realtime captioner. ] earlier today i spoke with a couple of business owners who had been here at least 60 years, two combis owners and they said
they never -- business owners. they never seen anything like this, a dramatic situation, that touched all in this area you might be stuck in traffic for a long time and you might be in the beauty parlor for a long time. the police are not taking any chances. this unbalanced man came into "discovery" today. they didn't know how powerful the explosives were. he had a gun, he had hostages. they were not taking chances and they still are not. we haven't heard reports about these other packages, how powerful they might be. one thing of interest. when they shot him, one of these explosives went off. we asked, how big are the explosion. they said they weren't sure
exactly what it was. they weren't even sure it went off the way he wanted or expected it to. it could have been a whole lot worse. as david leavy said, they closed it down, although it was inconvenient for a lot of commuters. look up where we were looking earlier where they had the entire wayne avenue blocked off with all sorts of different police vehicles and so forth. they are not allowing cars to cross. but they are allowing people crossing the streets now. they're coming out of the metro and crossing 29 colesville road and going about their business. there is a slight sense of normalcy starting to return to this area after a long and hectic and frightening
afternoon. there are vehicle. those are police vehicles leaving the scene right now. those are not public vehicle. those are private vehicles, i should say. those are police cars leaving the scene. people crossing right here in front of me, going about their business. maybe a slight sense of normalcy beginning to return but you get the sense for the folks waiting to get back inside that building you are looking at right now, the folks whose cars are there, purses or telephones, or whatever, they may not see that tonight. the thing from david leavy's statements, he wasn't sure they would open for business tomorrow. he was hopeful they would be but wasn't sure. the hostage situation is over. everybody is safe. but i have to say this evening is not over, not by a long shot. back to you. >> you're right, derek. the other thing that was interesting that david leavy's mentioned in this post-9/11 world is that this is a building that has done drills to get out
of the building. they floor captains. they let the floor know what happened. you need to know this is where we're going and this is where we're evacuating. and it is something that many office buildings and many of us are doing this now that we're in the new reality. >> there is a different vantage point of "discovery" there in the middle of silver springs. people, employees, who evacuated there quickly about 1:00, 130, after all of this started, still some waiting to get back in. we understand that the police have units and making sure there are no other dangerous explosives. this suspect was believed to have brought in boxes and backpacks with him and they're checking those out and probably canvassing the entire building to make sure that it is safe before people go back inside to collect some of their valuable that they need. >> and there is no timetable for
this because their job is to make sure the building is safe and not to make sure people can come in, get their purse and keys and get their cars. so this could be something that goes on for some time as well. we heard from the battalion chief from montgomery county, they're literally going to go floor to floor, room to room, to try to identify any potentially dangerous items. and if they come across something, it is their job to either clear it and make sure it is safe, or disarm it if it is not safe. that is a tough task as you look at the sprawling complex when you look at all of the floors and room and all of the areas they have to go through to locate these items. >> we heard through the afternoon from former bbi profiler who says after a situation like this goes longer, that is a good sign that things will hopefully end peacefully. but the s.w.a.t. team and snipers have to keep a close eye in any changes in the mood and
agitation level of the mood of the hostage-taker. what we heard in the last press conference. that is what happened. james lee was becoming more agitated, that they were able to watch him closely via a camera. it looks like they were threatening the hostages on the round. he said he was going to take them with them and at that point the situation changed from a negotiation situation to taking action, and the snipers again shot at him, some sort of device on his body also went off. so this could have been a much, more severe situation as far as lives lost. >> the profiler told us that in most cases hostages do walk away from situations like this safely, and that san diego good news about this. the three people who were taken hostage who were also "discovery" communication employees emerged safely. we'll send it back out to derek
mcginty. >> thanks, leslie. it is interesting, i was talking a little bit about things getting back to normal. wait a second, did i see cars drive down here? are these private vehicles coming through? look at this. these are folks coming down wayne avenue. i see vehicles turning and about to go down 29. we've got no official announcements about 29 being open again but you see it as well as i do, a private vehicle just going down the street. i don't know if that was someone who was at "discovery." we have to find out more information about that. that is good news for folks down here. look at mcdonald's. earlier i went inside that mcdonald's and it was completely abandoned. it was like people were spirited away. the lights were on and machines were running, but there was no people. it was evacuated. the security guard pretty much dragged me out of there. i was going to get a coke
because it was hot. earlier today it was literally crazy down here. that is when delia and i arrived. >> it was, as you said, complete chaos on the streets. there were folks evacuated from the "discovery" building, family members and co-workers, lot of folks holding babies from the daycare, very nervous. and folks didn't know what was going on at that point. we had lots of folks who left buildings nearby just to look at the action happening here and the police activity. it took nearly four hours but all of it came to an end but it was certainly a very tense situation here earlier today. >> i need all pedestrians to clear this lot immediately. >> chaos outside of the "discovery" channel in silver spring. 1:00 p.m. police say a gunman
entered a lobby waving a handgun canister bombs strapped to his chest. hundreds of employees are evacuated, nearby employees locked down. dozens of children from the day care strolled out in their cribs or in the arms of anxious parents. >> one lady came to me and said do not go to the lobby. there is activity going on out there. cops out there. >> we heard reports that there was a gunman in there. >> we had something last year, but i have no idea if this is related to that. >> reporter: the gunman held a small number of employees hostage but no one was injured. glad to see all these people get evacuated. >> they're telling you to go home? >> they told us to go home. >> you left your purse and everything. >> i borrowed money and hopped on the metro. >> at this point still negotiating with him, trying to
get him to release the hostages and surrender peacefully. >> of course, that was the goal that all of this would end peacefully. however, we now know at 4:48 the police moved in, the tactic units did fire and shoot, kill that suspect. he was inside and we're not certain if the body is still inside of the building at this point. however, we do know it is still a crime scene situation. they are looking at additional information and additional evidence that could be inside. >> absolutely they are. i just want to recap what andrea mccarren told us earlier, that the hostages were in serious jeopardy when the police made the decision to fieshgs they were lying face-down. perhaps the hostages made a move to try to get away. when the police realized he might be about to kill the hostage, they took him down. earlier on they weren't sure or weren't telling us whether or not he was deceased, but you got to think he was killed pretty quickly. what is when one of his
incendiary devices did go off. we have to find out how long it will take to clear the building. as i told you a bit earlier, the head of the bomb squad of montgomery county is here. he said we're in campaign mode right now. we're going up and down the building about to figure out exactly where these devices are, if they need to be cleared we'll clear them. if they need to be disarmed, we'll disarm them. you were talking to me a second ago, let me know where we were headed. thanks so much. i throw it back to you in the studio. >> thank you. derek, we'll check back in with you in a moment. other news going on because there is a hurricane out there and we need to update you on. we'll hear more about the track of earl. >> the track is getting closer to the mid-atlantic and we add updates we have tropical storm warnings for the entire delmarva. that means in the next 36 hours,
next day and a half we have at least tropical storm force winds. they will move in. here is the latest, hurricane warning from cape hatteras, south of there tropical storm warning. trop system graced the coast. we have the hurricane warnings south of here. late thursday, early friday, everyone showing the delmarva beaches here, that is the tropical storm warning. this is more going to be in the early morning hours on friday and through the afternoon. earl is a quick-moving system. this is going to be through by the time it is all said and done by friday evening. the current statistics, still a category 4, back now to category 4. it will drop down briefly to category 3 off the coast of north carolina. current wind speeds 135 miles per hour. gusts beyond 160 miles per hour. i've stopped it here just when it is going to get close to cape hatteras, outer banks of north
carolina. so we're still a day or two ahead from where we are right now. as we get to friday morning it is parallel to norfolk and d.c. it will start to wind down to category 2 status by this time friday. and friday afternoon merging from category 2 to category 1 and all out of here before we get to friday evening. the areas of concern, if you do have plans in the next couple of days, they will be overnight thursday and friday midday. it won't be until we get to labor day weekend things are looking good. so if you have plans for the eastern shore, things are actually looking just fine. let's go back to our weather for tonight. sunny and warm for evening. temperatures in the 80s. temperatures will be cooler in the outer suburbs, warmer downtown. another unhealthy quality day tomorrow. as we go through thurs afternoon it looks like it will be warm. bring the temperatures back
down. upper 80s to 90. lower to mid-90s for some. we stand at 94 in washington. high of 97 here today. still warm, at least the humidity has not been awful out there. the warm temperatures we start to see subside as we see the effects of earl on-shore. outer bands of clouds moving in. thursday afternoon and thursday evening. we could see a lot more cloud cover in washington as we go overnight friday, and these are friday morning hours. outer bands, tropical storm force winds at least expected over the delmarva store. it will be category 2 to category 1. dying down as the hurricane moves over cooler water. then we have to look at the effects of a cold front that brings us a shower. and then as we go into the holiday weekend, cooler drier air spilling in behind the front. it will be fall-like temperatures--temperatures starting to move in. even as we head to labor day
proper. temperatures as we go far west to far west. blue ridge, and lower 90s there. one or two clouds there. washington we're looking at temperatures a degree or two cooler from today. a high of 97, i'll bring it down to 93 or 94. fairly warm. in fact it is really warm for this time of the year but it won't be horrible. temperatures as you head to the bay and eastern shore, lower 90s and upper 80s. begin -- all eyes will be on earl. eastern shore, tropical storm warning going on overnight thursday through the better part of friday. that is the friday morning friday, and friday midday. if you have plans down south in north carolina, that is going to be thursday afternoon and thursday evening time period. washington, the only thing we really experience on our doorstep, a few more clouds, maybe a shower coming in, winds pick up a little bit, but it is not absolutely horrible, into labor day, things warming up again but we are looking for a
great holiday weekend. ladies? >> all right. thanks a lot. also tracking this for us, we're in virginia beach giving us a look at conditions there. winds are whipping up, bruce. >> yeah, anita, it is hard to believe that we could be looking at tropical storm-force winds here and heavy, heavy rain and flooding in just about 36 hours from right now, because at this point it is a spectacular day down here in virginia beach. earl is about 800 miles behind me out to sea, and the expectation is that it will turn right just off of hatteras. the hurricane watch extends to the north carolina state line which is about 10 to 20 miles from where i stand right now. excuse me, the hurricane warning extends there. and we're in the hurricane watch area. there are red flags flying here. the surf is already dangerous. but as you might imagine, the
surfers are having an absolute blast. it is a little bit flat right now, but the sets are about chest high and there are a ton of surfers out. come to the left unsee this giant sand berm they built here. you can perhaps see some of the kids that are playing here. this is a big, big weekend down here in virginia beach. as you zoom down towards the board walk down that way, you see the scaffolding along with the red flag, that scaffolding is for the american music festival and the emergency managers here are trying to decide whether they need to take that down, and they're going to be keeping a close eye on the track of that storm. if it tracks a little bit closer here, if they're too ticked to the west, they will definitely take the scaffolding down. look at the videotape. this is the uss cole, which came home early. it survived a bombing in the
middle east but it is concerned about hurricane earl and, in fact, the entire fleet at the norfolk naval base is a little bit concerned about earl and they're preparing on 24 hours' notice to deploy out to sea and to get out in front of this storm. we talked to someone who has sensible advice for everybody. >> when you are at the beach and the waves look great and the sun is sunshining and kind of wrapping up the summer, it is easy to minimize the fact that you have a big storm out there, and you think it is not going to hit and you have plenty of time. and the truth is, it is dangerous and it takes a lot of time to plan to get out. so if you're evacuating anyplace, the outer banks, virginia beach, new jersey or maryland, tough have a plan. it is not something you can do once the storm hits. >> of course, virginia is under a state of emergency as are a number of other states in the
area, and emergency managers say if you're thinking about coming down to the beach, watch the forecast, you may want to wait. we're hoping that it is out of here by late friday and the weekend may yet be good but you will want to keep an eye out. anita, back to you. >> we appreciate you keeping us posted. it does look nice down there. it depends what earl decides to document it can mess up your plans if it comes ashore. we'll go back to the top story, breaking news out of silver springs. they're still canvassing the area around the "discovery" area there. there was a hostage scene unfolding there. leslie and i have been following this. a 911 call came in this afternoon that someone fired
shots in the lobby. that individual, james lee, then took three hostages, three men, one security guard and two other employees, and all of this began to unfold. >> it did. and, you know, the s.w.a.t. team was watching very closely. they could see him through the angle of a camera. they could hear what was going on, and it is typically protocol that a hostage negotiator tries to negotiate a situation down. so they were trying to talk with him for several hours, but at a certain point he became agitate #. and when it -- he appeared agitated. when he began to move, the police said, lee apparently reached down to grab a weapon and that is when they felt those hostages' lives were in danger, they moved in, they shot him, he died. apparently one of the explosives on him, blew up in some way. now, was it loud? was it soft? what was the noise?
so we were not able to get a clear depiction of what that was, but the net is that all of the employees in that building who worked for "discovery" did emerge today safely. the gunman did not. >> the bomb-sniffing canine still around the building. and the employees who have cars and belongings still inside there, after clearing the building, we are not told at this point how long that will take. go back to hurricane earl. lot of people talking about this especially with the long holiday weekend coming up. we have scott broom in ocean city with concerns there. hey, scott. >> good evening. great job keeping up with the developments in silver spring. while all of that was going on, we had headlines in ocean city, the headline is that ocean city is not considering any evacuation plan at this point. only thing we heard from the official on the delmarva coast said to watch the situation and
adjust your travel plans for friday. but the beach will be open for business on saturday. >> we are within the tropical storm-force wind field. >> reporter: the storm briefing today emergency managers and city leaders were told earl will likely pass more than 200 miles out to sea. at this point we don't have any consideration for evacuation at all. if the forecast colds, the mayor says at worst visitors should adjust travel times friday but otherwise not cancel plans. >> hopefully this is nothing more than an exercise. >> you don't want to drive during a storm. consider delaying your coming to ocean city. wait until the storm passes. use prudent and common sense judgment and we'll all get through this together and you'll be able to enjoy the beaches come saturday. >> we may restrict you can go and how far out you can go depending upon the surf. maybe restricted up to your knees only. but i think you're safe to come travel and enjoy the ocean city beach this weekend.
>> so a fear of heavy surf after the storm passes is really the most significant danger they're focussed on here. they will have a full lifeguard contingent on the beach and they're asking the lifeguards on the duty to pay attention because they'll impose those restrictions. so it is a come on down kind of posture here in ocean city. storm force winds on friday. some minor coastal flooding. in ocean city that is not regarded as a huge big deal. they're asking travellers to adjust their travel plans. it will be spectacular weather through the weekend. down at the convention center there is a crafts festival. they are expecting a full talent despite the hurricane forecast. all of this is contingent of whether that forecast holds up. if it holds up the way it is
shaping up, they say come on down. scott broom, 9 news now. >> all right. scott. and devon is telling us there can be beach erosion there, storm swells there and definitely some showers and storms but hopefully not enough to completely dampen your plans if you do have plans to go down that way. we want to refocus our coverage and get you back to the "discovery" story. the hostage situation is over. the hostages that were taken, three of them, are safe. but the gunman is dead after hours upon hours of negotiating did not seem to work. >> that's right. our derek mcginty has been field anchoring all of this after coming upon the scene literally just a few minutes after it all started and giving us a play-by-play, as you kept getting more and more information, dribs and drabs by the police. now we're getting a clearer picture of what happened there. >> we are indeed getting a much more clarified picture of
exactly what went down today. it was in essence four hours of hell here in downtown silver springs, folks running all over the place, folks very afraid. somebody holding three hostages indecide the discovery channel and everybody evacuated. the whole area on lock down. and this is as rush shower approached in one of the busiest parts of town. it has indeed been a crazy, crazy day. the thing is, folks, it is not over, yet. the police explained how the whole thing ended in terms of the hostage-taker, and they also said there was the bomb squad hard at work because he left packages and bombs, whatever, and they were not going to open the building until they have the bombs out of there. andrea mccarren has been talking to some folks and has more on how this information is unfolding. >> as derek said , this scene is far from over. the "discovery" building behind us is still considered an active crime scene. the bomb squad officials, the
battalion chief kevin frazier said that they will take as much time as they need to methodically comb through that building to ensure that there are not explosive devices. earlier i heard you talking about the negotiations. obviously they failed. however, while the negotiations were under way, snipers were put in position and they were -- via security cameras and simply eyeballing the suspect, were watching his every move. the hostages were face-down on the floor, the suspect at some point got agitated, apparently, picked up his weapon, the hostages tried to move, and that is when one of the snipers shot the suspect dead. so it's been an extraordinary afternoon here. not something that you see everyday in silver spring. >> no, but i think you have to notice just how quickly they were able to mobilize. i was here at 1:00, 130, 2:00, something like that, and this place was already swarmed with
police officers. the whole thing got started at 1:00. >> it helps, discovery communications has held regular evacuation drills, i'm told by employees. we also know, we asked about the three hostages, one of them was a security guard in the lobby of "discovery." we don't know whether or not he was armed. >> actually i don't want to cut you off but we know that. david leavy the vice-president of "discovery" who was just out here maybe a half hour, 45 minutes ago said he was not afrmd. and so you got to wonder now -- he was not armed. you might think will they rethink that. compared to the situation at the holocaust museum where two or three armed guards were able to stop something from becoming more tragic even though they lost one guard there. >> investigators believe that two men, all three hostages were male. the security guard as well as two what we believe are employees. and investigators believe at this point that they were
selected at random. when people in the lobby saw the man with the gun, apparently a lot of people tried to flee, for whatever reason the suspect apparently stopped these men in their tracks and held them. they were not tied with anything but simply held hostage with his weapon. >> we should know that, and as we talked to, again, the chief and david leavy, the vice-president of "discovery," look, were these guys picking people and were they targeted? the answer is no, it seemed that they were randomly there. people in the wrong place at the wrong time. this crazy fellow walked in, david lee -- james lee, and began to make a move. and that's what -- that's how this whole thing got started. >> okay. anita, back to you. >> all right. thank you so much. obviously so much happening all afternoon and we appreciate you staying with us here on wusa9 and wusa9.com.
we will continue our coverage of this major story of 9 news now at 7. [ captioner switch ] switch >> and that worst case scenario applantly happened when the hostages tried to move or moved in some way and that seemed to, place say, maybe agitate the hostage-taker, james lee. they saw him reach for what
CBS September 1, 2010 6:30pm-7:00pm EDT
TOPIC FREQUENCY David Leavy 5, North Carolina 4, Washington 4, James Lee 3, Virginia Beach 3, Anita 3, Virginia 2, Andrea Mccarren 2, Leslie 2, Derek Mcginty 2, Scott 2, Norfolk 2, Hatteras 2, Devon 1, Unsee 1, Scaffolding 1, Category 1, Bbi 1, Maryland 1, New Jersey Or Maryland 1

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by 2010prresearch
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Gamification in Libraries Teen Tech Week Joe Murphy Sponsored by Tutor.com 2.
Gamify for fun and inspirationImage originally pinnedby Casey Landau 3.
Gamification is Using game-likecompletingtotasks attention and provide rewards for elements hold Search of “gamification” in Pinetrest.com reveals the term’s many applications 4.
A General Overview We are never more human than when we play - Johan Huizinga http://www.dashe.com/blog/lcbq-2/gamification-in-workplace-learning-the-role-of-play“gaming is fundamentally a part of being human.” - Jane McGonigal http://www.alternet.org/education/154226/can_computer_games_save_us _all_the_alternet_interview_with_jane_mcgonigal/?page=entire 5.
Check out this book by Jane McGonigal – Reality Is Broken: Why Games Make UsBetter and How They Can Change the World 6.
The Many, Many Benefits of GamificationMore wisdom from Jane McGonigal• Increase our resilience to face challenges• Problem solving• “blissful productivity”• Meaning and bigger purpose – http://www.alternet.org/education/154226/can_computer_games_save_us_all_the_alternet_interview_with_jane_mcgonigal/?page=entire 7.
YALSA Competencies• Area II. Knowledge of Client Group.• The librarian will be able to: – Become familiar with the developmental needs of young adults in order to provide the most appropriate resources and services. – Keep up-to-date with popular culture and technological advances that interest young adults. 8.
Area III. Communication, Marketing & Outreach • 3 - Be an advocate for young adults and effectively promote the role of the library in serving young adults, demonstrating that the provision of services to this group can help young adults build assets, achieve success, and in turn, create a stronger community. • 8 - Promote young adult library services directly to young adults 9.
• Area V: Knowledge of Materials• Area VI - Access to Information• Area VII. Services• … nearly all 10.
“contrary to prevailing stereotypes, theaverage social gamer is a 43-year old woman” “The vast majority (95%) of social gamers play multiple times per week; nearly two-thirds (64%) play at least once a day.”http://popcap.mediaroom.com/index.php?s=43&item=149 11.
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Smartphone penetration reaches Young Adultshttp://blog.nielsen.com/nielsenwire/wp-content/uploads/2011/11/Smartphone_agegroups.gif 20.
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Areas for Opportunities for libraries• Attracting and holding attention• Harnessing engagement• Introducing the library• Teaching skills• Providing interesting services• Interacting – patrons/staff/library/content 23.
Find the Future at the New York Public Library• “game that could get young people excited about libraries, specifically the physical space of a library, because young people today do all of their research on the Internet and never come into the actual building.”• http://game.nypl.org/#home• “what do young people want, and how can the library help them achieve that?” – http://www.alternet.org/education/154226/can_computer_games_save_us_all_the_alternet_interview_with_jane_ mcgonigal/?page=entire 24.
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Library Orientation• Scavenger hunts for learning the library• Gamifying learning online resources Reading Events • Social gaming and co-reading • Interaction in person 27.
Gamifying Instruction• Learning and play• Locating• Sharing• Engaging• Citing Gaming Service • Reference • Communication 28.
Gamification and Content• Discovery• Sharing• Self curation• Interactive ebooks Pinned by Barbies World pinterest.com/pin/144537469260399491/ http://scaraboo.posterous.com/colouring-pencils 29.
QR Codes• Scavenger hunts• Discovery• Sharing• Accessing content• Adding mobile play to the library experience• Turning the library into an experiment • Cheap! 30.
Pinned by Kristen Friedrich pinterest.com/pin/273523377338101904/ http://www.thedailyawe.com/2010/09/monday-motivation-have-fun/Can be synonymous with “did you learn at the library today?” 31.
“The real game begins once user starts checking- in to machines on a regular basis. Each check- in awards the user points that can be spent to customize their machine. These virtual items include shoes, character skins, and backgrounds.”http://www.penn-olson.com/2011/11/10/coca-cola-gamifies-its-vending-machines/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+PennOlson+%28Penn+Olson+|+Techin.asia%29 32.
Gamify Teen Tech Week 33.
Gaming the Future Pinned by KelleyAnne pinterest.com/pin/86835099034739556/ http://printpattern.blogspot.com/2010/12/wall-art-steph-baxter.htmlBe Inspired, Have Fun, Game On English


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The Pigman book | 26 available editions | Alibris Books
1983, Bantam Doubleday Dell Publishing Group
12774679105
0553168827
12689032688
12665434346
Fine. Softcover book in Great clean condition. FREE upgrade to First Class Mailing. Most orders ship same or next day with Delivery confirmation. Guaranteed quality PB.
12760549713
12747317033
12715727655
12764374847
12787446039
12755444028

value: This website is is an online store that sells new books, used books, out-of-print books, rare books, and other media through an online network of independent booksellers.


text:
Mary Hopkin, Now and Then: Amazon.co.uk: Music
Mary Hopkin, Now and Then
Y Caneuon Cynnar - The Early Recordings Mary Hopkin
B000QGE7KW,B001N2Z446,B001QITNM6,B003XSSR8I,B003XSSR9C,B000024QOZ,B0047PQUUS,B00BPBWYM0,B0098JR4CG,B0098JR4AI,B0002SG1P8,B005H0HEJ8,B005H0HEIE,B00CXDKEAI,B003O7Z1A0,B003O7Z19G,B003O7Z19Q,B003J0LDRM,B003O7Z196,B003KTNW30,B003SX4Q7E,B003O7Z1AA,B003OBT5JY,B00004SHMV,B0085B39H2
ASIN: B002A03J10
Amazon Bestsellers Rank: 37,204 in Music (See Top 100 in Music)
1386816790
Format:Audio CD `Now And Then', features three Mary Hopkin originals as well as songs from legendary names including Bert Jansch, Tom Paxton, Jim Croce and John Kongos. Some of the tracks have been brought bang up to date with the use of modern technology and they sound amazing...
- Published on Amazon.com Amazon Verified Purchase includes her comeback single and sounds very much like updated folk-pop. Mary's career was never the same after she left Apple as the post-apple recordings reflect and I think she preferred it that way.1. Take Me Back-The words are beautiful and Mary's voice is rich and clear and as beautiful as ever. 8/102. Crazy For My Sweetheart-A more acoustic song and Mary at her best with this folky tune. 9/103. Who Will Be-An uptempo pop song with a slight sixties feel to it, pretty good. 8/104. Life Song-Mary had already given us Earth song, Ocean Song and thissong compliments the other two very well though its less folky but it makes for a good trilogy. 9/105. When He Shines-Mary singing a Carole King type song with less guitar and more piano with mixed results. 7/106. Tell Me Now- Her post-Apple b-side to her comeback single written by her. Very nice. 8/107. What A Friend You Are-This is more the Mary I like and know with mostly guitar and that voice. 9/108. Wrap Me In Your Arms-A song that should have given Emmylou Harris a run for her money-had it succeeded-her second single 9/109. Brown Eyes and Me-The voice and guitar again-very good. 9/1010. One Less Set of footsteps-A song with a slightly country twang, very uptempo and very good. 9/1011. Shamarack-Folky and perfect. 9/1012. If You Love Me-The comeback single and also an Edith Piaf song in english. Has a hint of "Those Were the Days" style in it. Sounds like classic Mary of Apple days. Nostalgia should have made this a bigger hit. It reached #32 in the UK 9/1013. Bitter Harvest-A James Taylor Carly Simon-like song that could have been a minor hit. 9/1014. Happy Birthday-Makes the birthday song all her own with thatvoice-a must-listen to! 9/10Overall not a classic album, but an undated album of its time by anunderrated true talent. 4 out of 5 stars.

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text:
Primary Care Mentor: Your Clerkship & Shelf Exam Companion book by Marianne M Green, Jennifer A Bierman, James J Foody | 1 available editions | Alibris Books
Books Medical Test Preparation & Review Primary Care Mentor: Your Clerkship & Shelf Exam Companion
Marianne M Green, Jennifer A Bierman, James J Foody
9780803621251
0803621256
13509327155
13538749185
13459493516
13520739211
13344816160
13240296871
13477121761
13549118661
13537077767
13556365770
ISBN-13: 9780803621251
by Marianne M Green, Jennifer A Bierman, James J Foody
Starting at $0.99	The J2EE Tutorial
Starting at $0.99	Linguistics and Computation
by Jennifer S Cole Starting at $5.99	Bates' Pocket Guide to Physical Examination and History Taking


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Mani Pedi in Hollywood, FL with Reviews - YP.com
Hollywood, FL Mani Pedi
1. Waterless Mani Pedi
6190 W Sample RdPompano Beach, FL 33067
2. Waterless Mani PediMOVED
10878 Wiles RdCoral Springs, FL 33076
From Business: At Waterless Mani Pedi nail salon we make the health and safety of our clients our ultimate priority. We autoclave our tools to exceed State board requirements. W…
4. isis nail spa $25Pedi
5701 Sunset Dr Ste 234south miami, FL 33143
5. DG Deluxe Nails
9. Goldensun Tan
3100 Oakwood BlvdHollywood, FL 33020
(954) 927-2667
Coupons & DealsUp to 47% Off at GoldenSun Tan
Tom was extremely nice upon entering actually felt like I have known him for years. Have seen the salon for years but it's the first time I come in.…
10. Drew James Coiffures Inc
11. Kats Nails and Spa
12. Elegance Salon and Spa Inc.
6630 Stirling RdHollywood, FL 33024
(954) 391-7180
Day SpasHair RemovalNail SalonsWax
13. Who Did Your Nails - CLOSED
(954) 965-2999
14. Balleria Nail Spa
(754) 777-7960
15. Zaria Salons
16. Massage Rio Spa
17. Us Nails
6645 Taft StHollywood, FL 33024
(954) 964-9450
18. Organic Nail Bar
633 S State Road 7Hollywood, FL 33023
(954) 894-4090
This place is good as long as you go to the right person. The 3 women do a better job than most of the men there. The older guy did my acrylic manic…
9279 Sheridan StHollywood, FL 33024
23. Doris Beauty Salon
6796 Stirling RdHollywood, FL 33024
(954) 983-5755
24. Hollywood Institute of Beauty Careers
Coupons & DealsUp to 46% Off Spa Services
25. Nails By Deanna
26. Salonz Beauty Suites & Rentals - Hollywood
27. Gigi’s Hair Extensions
28. Charms Nails And Spa
7532 Arthur StHollywood, FL 33024
(754) 208-2597
30. Mpt Nails
Thanks a lot for my skin treatment. It was a very good experience. I would definitely come back. Morlie was great.

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