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The living embodiment of the Beatles, a musical juggernaut without parallel, Paul McCartney is undoubtedly the senior figure in pop music today. In this authoritative biography, journalist and acclaimed author Howard Sounes leaves no stone unturned in building the most accurate and extensive profile yet of music's greatest living legend. He is one of the biggest stars that has ever existed, the only key member left from the unquestioned 'biggest band of all time'.
As Hitler was attempting to conquer the western world, his armies were methodically pillaging the finest art in Europe, from Michelangelos to Vermeers, all stolen for the Führer. The Monuments Men had a mandate from President Roosevelt to find these artworks, but no vehicles, typewriters, or authority. In a race against time to save the world's greatest cultural treasures from destruction at the hands of Nazi fanatics, each man constructed his own treasure map....
"Soon to be a movie"
As a young man, Ed Catmull had a dream: To make the world's first computer-animated movie. He nurtured that dream first as a Ph.D. student at the University of Utah, where many computer science pioneers got their start, and then forged an early partnership with George Lucas that led, indirectly, to his founding Pixar with Steve Jobs and John Lasseter in 1986. Nine years later and against all odds, Toy Story was released, changing animation forever.
"A truly inspiring book"
In a sodden tent at a '70s festival, the teenage Mark Ellen had a dream. He dreamt that music was a rich meadow of possibility, a liberating leap to a sparkling future, an industry of human happiness - and he wanted to be part of it. Thus began his 50-year love affair with rock and roll. From his time at the NME and Smash Hits to Radio One, Old Grey Whistle Test, Live Aid, Q, Select, Mojo, and The Word magazines, he's been at the molten core of its evolution, and watched its key figures from a unique perspective.
"Highly entertaining autobiography in music"
"Flaubert believed that it was impossible to explain one art form in terms of another, and that great paintings required no words of explanation. Braque thought the ideal state would be reached when we said nothing at all in front of a painting. But we are very far from reaching that state. We remain incorrigibly verbal creatures who love to explain things, to form opinions, to argue.... It is a rare picture which stuns, or argues, us into silence."
Great music is a language unto its own, a means of communication of unmatched beauty and genius. And it has an undeniable power to move us in ways that enrich our lives-provided it is understood.If you have ever longed to appreciate great concert music, to learn its glorious language and share in its sublime pleasures, the way is now open to you, through this series of 48 wonderful lectures designed to make music accessible to everyone who yearns to know it, regardless of prior training or knowledge.
"A treat for ears and heart"
Here is a new audio edition of the acclaimed BBC Radio 4 dramatisations of Anthony Trollope's gently satirical tales of provincial life, available together in one download. Nearly 20 hours of ironic, witty, and wonderfully written drama is contained in this audiobook. The cast includes Anna Massey, Alex Jennings, David Haig, Rosemary Leach, Kenneth Cranham, Emma Fielding, and Brenda Blethyn.
"Barchester comes alive!"
The secrets of creative thinking by a lecturer at the world famous St. Martin's College of Art who has spent a lifetime researching innovative thinkers. A scuba-diving company faces bankruptcy because sharks have infested the area. Solution? Open the world's first extreme diving school. The Art of Creative Thinking reveals how we can transform ourselves, our businesses, and our society through a deeper understanding of human creativity.
"Absolutely brilliant"
Stein on Writing provides immediately useful advice for writers of fiction and nonfiction, whether newcomers or accomplished professionals. As Sol Stein, renowned editor, author, and instructor, explains, "This is not a book of theory. It is a book of usable solutions, how to fix writing that is flawed, how to improve writing that is good, how to create interesting writing in the first place."
"This book has improved all my writing"
Here's a rhyming story of a mouse and a monster. Little mouse goes for a walk in a dangerous forest. To scare off his enemies, he invents tales of a fantastical creature called the Gruffalo. So imagine his surprise when he meets the real Gruffalo.
"Great Story"
Written by Jennifer Worth, Farewell to the East End is one of the trilogy of memoirs upon which the popular BBC series Call the Midwife is based. London's East End in the 1950s was a vibrant place-a close-knit community of families where children made playgrounds on bombsites and a lively social scene emerged.
"Brilliant !"
A classic BBC Radio full-cast production of Dylan Thomas' poetic play for voices starring Richard Burton as the narrator. To begin at the beginning: it is spring, moonless night in the small town, starless and bible-black.... When Richard Burton breathed the opening words of 'Under Milk Wood' into a microphone, broadcasting history was made.
"Under Milk Wood"
Strong of will and slender of ankle, 20-year-old orphan Flora Poste is blessed with every virtue save that of being able to earn her own living. Casting around for suitable relatives with whom she can make her home, Flora alights on the mysterious Starkadders and, ignoring the horrified shrieks of her friends, heads down to darkest Sussex.
"Absolutely brilliant!"
In 1991, five wannabe Mancunian musicians came together and cracked the spark that ignited the explosion which became Oasis. The band went from obscurity to a global phenomenon in the space of a year, achieving world-wide recognition and selling over 70 million records. What started out as five young lads with a common dream of becoming rock stars eventually disintegrated into in-fighting, clashes of egos, and financial disputes.
"great insight"
For more than a quarter of a century, Philip Norman's internationally best-selling Shout! has been unchallenged as the definitive biography of the Beatles. Now, at last, Norman turns his formidable talent to the Beatle for whom belonging to the world's most beloved pop group was never enough. Drawing on previously untapped sources, and with unprecedented access to all the major characters, here is the most complete and revealing portrait of John Lennon that is ever likely to be published.
"Never written a review before, but..."
Have you ever wondered how off-key you are while singing in the shower? Or if your Bob Dylan albums really sound better on vinyl? Or why certain songs make you cry? Now, scientist and musician John Powell invites you on an entertaining journey through the world of music. Discover what distinguishes music from plain old noise, how scales help you memorize songs, what the humble recorder teaches you about timbre (assuming your suffering listeners don't break it first), and more.
"Music is my business"
A Victorian epic of awful schools inc the aptly named St Bastards, worse prisons, nuns at St Bitches, giant rabbits, and long lost super-hero aunts, in the style of Charles Dickens after far too much gin.
"Oliver with a Twist or a Tall Tale of no cities"
Robert McKee's screenwriting workshops have earned him an international reputation for inspiring novices, refining works in progress, and putting major screenwriting careers back on track. Quincy Jones, Diane Keaton, Gloria Steinem, Julia Roberts, John Cleese, and David Bowie are just a few of his celebrity alumni. Writers, producers, development executives, and agents all flock to his lecture series, praising it as a mesmerizing and intense learning experience.
"Just great"
Easy Rider, Raging Bulls follows the wild ride that was Hollywood in the 70s - an unabashed celebration of sex, drugs, and rock 'n' roll (both on screen and off) and a climate where innovation and experimentation reigned supreme.
"Bitchy and Sensationalist intrigue from Hollywood"
Wie eine Bierwerbung den Aufstieg dieser Band begründet und warum Blur nichts mit B2-Bombern zu tun haben möchte.
Dieser Titel ist Teil des Pop-Splits "Wind of Change -21 Geschichten über Politik und Zeitgeschehen".
There is now no doubt that not only is Waiting for Godot the outstanding play of the 20th century, but it is also Samuel Beckett's masterpiece. Yet it is both a popular text to be studied at school and an enigma. The scene is a country road. There is a solitary tree. It is evening. Two tramp-like figures, Vladimir and Estragon, exchange words. Pull off boots. Munch a root vegetable. Two other curious characters enter. And a boy. Time passes. It is all strange yet familiar.
"Stay go leave stay...it's all the same"
Presenting your lover with 24 roses signifies that they are always on your mind, for each rose represents one hour of the day. 24 Roses is a series of poems that explore the powerful and varied raw emotion that is love in all its glory. From the innocent love of childhood sweethearts to the weathered relationships of those who grow old together, and the anger, infatuation, despair, and romance in between.
With his ongoing exploration into actor behavior and an ever-innovative body of work, Richard Maxwell has written a study guide to the art of making theater. This illuminating volume provides a deeper understanding of his work, aesthetic philosophy, and process for creating theater.
"It's been a quiet week in Lake Wobegon, my hometown..." Garrison Keillor first did his monologue in 1974 to an audience of 20 in a St. Paul theater. Today, more than 2.2 million people tune in each week to hear the tall tales and sweet stories about the citizens of this small Minnesota town. It's a town where "the women are strong, the men are good-looking, and all of the children are above average."
Do you struggle with taking beautiful pictures? Do you want to know the secrets that professional photographers use to get phenomenal pictures? In this audiobook we give the proven techniques that some of the best photographers in the world use. You will learn what equipment and angles are needed for breathtaking pictures.
Regina Puckett's Complete Book of Poetry has over 400 poems.
Sex symbols, whether from the past or present, allure like little else. Though many sex symbols have emerged over the years, three have triumphed as American icons: Rudolph Valentino of the 1920s, the Beatles band of the 1960s, and Justin Bieber of today. Through poetry, this work praises beloved American icons, while attempting to harness and integrate their charismatic powers. Hopefully, these prominent icons will inspire other sex symbol icons to emerge in the very near future.
Salvador Dalí, Jerome Robbins, Jackie Onassis. Gregory Peck, Mick Jagger, S. J. Perelman, I. M. Pei. Philip Johnson, Josephine Baker, John Lennon: They, and so many more who made New York City the center of the universe in the 1970s, all had one thing in common besides their adopted hometown - they shopped at a legendary palace of books, music, and art: Rizzoli Books at 712 Fifth Avenue. There, Kennedys and Rockefellers mingled with tourists and "regular" customers under the watchful gaze of sophisticated employees.
An American institution, Sun Records has a history with many chapters: its Memphis origins with visionary Sam Phillips, the breakthrough recordings of Elvis Presley, and the studio's immense influence on the sound of popular music. But behind the company's chart toppers and legendary musicians there exists another story, told by Barbara Barnes Sims. In the male-dominated workforce of the 1950s, 24-year-old Sims found herself thriving in the demanding roles of publicist and sales promotion coordinator at Sun Records.
Calligraphy is a long lost art, derived from the two Greek words kallos and graphe, translating to "Beautiful Writing". In this book I'm going to teach you in simple terms how to learn and master the art of calligraphy - covering everything from your writing tools to moving forward after you've got it mastered! Calligraphy will never die!
This is the first biography of Ralph Peer, the adventurous - even revolutionary - A&R man and music publisher who saw the universal power locked in regional roots music and tapped it, changing the breadth and flavor of popular music around the world. It is the story of the life and 50-year career, from the age of cylinder recordings to the stereo era, of the man who pioneered the recording, marketing, and publishing of blues, jazz, country, gospel, and Latin music.
In this short assortment of poetry and prose, I include nine poems, two works of prose, and two Facebook quotes. Everything written here is presented in chronological order from 1992-2013, over the span of more than 20 years of my life. I hope you enjoy, and I thank you for listening!
This audiobook is an ideal place to start your journey into the world of Minecraft. You will get all the guidance you need, from harvesting blocks to crafting your tools and building shelter amidst the lurking dangers. From the different modes and biomes, to the mobs and versions present, this audiobook gives a comprehensive tour of the game, so you won't feel like a beginner when you start the game. There are some tricks and tips too, which help you jump past fatal traps and emerge victorious.
Author Avery Washington's style of poetry is compassionate and thought provoking. His childhood experiences, being raised by a single mother, have created this huge heart he has for women and children. Avery Washington's gift of words in Mother reads as a universal anthem for respecting the beautiful women in our lives. He has created a unique platform to pour out his love for not only his family, but for other families as well, setting an example that men can revere women without being regarded as weak.
Though it may be hard to believe today, the Eiffel Tower was initially met with derision by many Frenchmen, some of whom compared it to the Tower of Babel and complained that the "useless and monstrous" structure would obscure treasures such as Notre Dame. In response to such criticisms, Eiffel himself pointed out, "Can one think that because we are engineers, beauty does not preoccupy us or that we do not try to build beautiful, as well as solid and long lasting structures? Aren't the genuine functions of strength always in keeping with unwritten conditions of harmony?
Poetical pods that pop and burst,and reveal flavors of situational circumstance. Sickly sweet, bitter and tangy, sour and tart, it doesn't matter, but they should all leave a taste on the tongue. That is poetry for me. Once consumed, the stain of taste should still be there, for a while at least, I think. What about you? What do you look for? What flavors sate your poetical thirst?
The antebellum era and the close of the 19th century frame a period of great agricultural expansion. During this time, farmhouse plans designed by rural men and women regularly appeared in the flourishing Northern farm journals. This book analyzes these vital indicators of the work patterns, social interactions, and cultural values of the farm families of the time. Examining several hundred owner-designed plans, McMurry shows the ingenious ways in which "progressive" rural Americans designed farmhouses in keeping with their visions of a dynamic, reformed rural culture.
Mick Jagger has described Phil Kaufman, America's legendary road manager, as the entertainment industry's "executive nanny."
Woodstock, more accurately entitled the Woodstock Music Festival; An Aquarian Exposition: Three Days of Peace and Music, represents one of the most enduring symbols of the youth movement of America's late 1960s and early '70s. As the public pinnacle of that social phenomenon, the giant festival that overwhelmed a section of an upstate New York farm for a week during a time of national and international upheaval evolved from a typical speculative financial venture to a defining historical monument.
This book was written over the course of years of love, heartbreak, and life in general. Powerful poems that will touch your heart. Poems that you can relate to, and some that might even make you shed a tear of happiness, or for understanding the pain of heartbreak. Join me and follow the paths through life!
Former English cricketer Mike Gatting talks to Danny Kelly in the studio. The successful batsman played world-class cricket for Middlesex and was captain for 14 years. Alongside this he also captained England in 23 test matches.
An introduction to philosophy through film, Thinking Through Film: Doing Philosophy, Watching Movies combines the exploration of fundamental philosophical issues with the experience of viewing films, and provides an engaging reading experience for undergraduate students, philosophy enthusiasts and film buffs alike. An in-depth yet accessible introduction to the philosophical issues raised by films, film spectatorship and film-making.
She seemed to have it all: children, a handsome husband, and a trust fund. But in the early 1950s, Nica Rotschild heard "Round Midnight" by the jazz legend Thelonious Monk; the music overtook her like a magic spell, and she abandoned her marriage to go and find him. She was shunned by society but the musicians gave her friendship. She gave them material and emotional support. Her convertible Bentley was a familiar sight outside the clubs; her notoriety was sealed when Charlie Parker died in her apartment. But her real love was reserved for Monk, whom she cared for until his death in 1982.
"Pa-dum-pum-pa-dum-pum - PUM!" Super Mario Bros. for the NES contains some of the most recognizable tunes in popular culture, and yet it's safe to say that only a handful of people have thought beyond the music's entertaining surface. After all, what could possibly be art-worthy about an early Mario score? Or any early game sound for that matter? In search of answers to these questions, Andrew Schartmann takes us on a journey from the primitive "pongs" of arcade machines to the complex musical fabrics woven by composers of the NES era.
Ted Gioia's History of Jazz has been universally hailed as a classic - acclaimed by jazz critics and fans around the world. Now Gioia brings his magnificent work completely up-to-date, drawing on the latest research and revisiting virtually every aspect of the music, past and present. Gioia tells the story of jazz as it had never been told before, in a book that brilliantly portrays the legendary jazz players, the breakthrough styles, and the world in which it evolved. Here are the giants of jazz and the great moments of jazz history.
"Thorough, Thought provoking and clear"
From young artists trying to elbow their way in to those working hard at dropping out, White's essential audiobook offers a once-in-a-generation glimpse of the inner workings of the American art world at a moment of unparalleled ambition, uncertainty, and creative exuberance.
First published in 1973, this is a study of the force of photographic images, which are continually inserted between experience and reality. When anything can be photographed, and photography has destroyed the boundaries and definitions of art, a viewer can approach a photograph freely, with no expectations of discovering what it means. This collection of six lucid and invigorating essays, with the most famous being "In Plato's Cave", make up a deep exploration of how the image has affected society.
"hard going"
Unlike all previous versions of rock 'n' roll history, this book omits almost every iconic performer and ignores the storied events and turning points everyone knows. Instead, in a daring stroke, Greil Marcus selects 10 songs recorded between 1956 and 2008 and then proceeds to dramatize how each embodies rock 'n' roll as a thing in itself in the story it tells, inhabits, and acts out - a new language, something new under the sun.
Smart and incisive, this unique book takes us through Bruce Springsteen's life by tracing the cultural, political, and personal forces that shaped his music. Beyond his constant stylistic adaptations, Springsteen developed over the decades from expressing the voice of a guy from working-class New Jersey to writing about the larger issues facing the country, including war, class disparity, and prejudice. Marc Dolan draws on a range of new and little-known sources - including hundreds of unreleased studio recordings and bootlegs of live performances - making this an indispensable reference for avid Springsteen fans as well as those interested in learning the stories behind his music.
Low is a kaleidoscope in which Bowie's obsessions and traits explode into fragments and reform in a new pattern. Sonically, it is hugely adventurous: combining a driving R&B rhythm section with the experimental soundscapes of Brian Eno, it evolves a whole new musical language. Thematically, it's the sound of a man struggling to get well. Bowie has often talked about his fear of insanity.
"How many times can you say "Parenthesis" in 4 hrs?"
In Catch a Wave, Peter Ames Carlin pulls back the curtain on Brian Wilson, one of popular music's most revered luminaries, as well as its biggest mystery. Drawing on hundreds of interviews and never-before heard studio recordings, Carlin follows the Beach Boys from their earliest days through Brian's deepening emotional problems to his triumphant re-emergence with the release of Smile, the legendarily unreleased album he had originally shelved.
Inside the Business of Graphic Design casts a precise and realistic light on the risks, requirements, and rewards of running a creative and successful design business. Whether you dream of setting up a small studio, or whether you've been on your own for years, this provocative guide is an important source of success strategies for every graphics professional.
The Rape of Europa is one of Titian's great masterpieces, a work charged with eroticism and classical mystique behind which lies a tale as compelling as the painting itself. Here Charles FitzRoy weaves a unique account of its history and the painting's movement following the rise and fall of the countries in which it has been housed. This is the tale of how Titian's masterpiece has captivated kings, nobles, artists, and lovers alike for over four centuries since its conception and continues to do so today.
Early in his philosophical career, Wittgenstein cryptically remarked that "Ethics and aesthetics are one and the same. But is the good really interchangeable with the beautiful?" While aesthetics and moral values often do seem to go hand in hand, we all know that the devil is in the details. Art and Ethical Criticism explores these elusive details to shine a scholarly light on the complex relationship between the arts and morality.
From one of the most acclaimed and profound writers in the world of comics comes a thrilling and provocative exploration of humankind's great modern myth: the superhero. In this exhilarating work of a lifetime, Grant Morrison draws on art, science, mythology, and his own astonishing journeys through this shadow universe to provide the first true history of the superhero - why they matter, why they will always be with us, and what they tell us about who we are... and what we may yet become.
"Part biography, part comic book history."
Non-fans regard Celine Dion as ersatz and plastic, yet to those who love her, no one could be more real, with her impoverished childhood, her (creepy) manager-husband's struggle with cancer, her knack for howling out raw emotion. There is nothing cool about Celine Dion, and nothing clever. That is part of her appeal as an object of love or hatred - with most critics and committed music fans taking pleasure (or at least geeky solace) in their lofty contempt. This book documents Carl Wilson's brave and unprecedented year-long quest to find his inner Celine Dion fan, and explores how we define ourselves in the light of what we call good and bad.
Contemporary art has never been so popular - but what is 'contemporary' about contemporary art? What is its role today, and who is controlling its future? Julian Stallabrass takes us inside the international art world to answer these and other controversial questions, and to argue that behind contemporary art's variety and apparent unpredictability lies a grim uniformity. Its mysteries are all too easily explained, its depths much shallower than they seem.
Film Music: A Very Short Introduction is a compact, lucid, and thoroughly engaging overview written by one of the leading authorities on the subject. After opening with a fascinating analysis of the music from a key sequence in Quentin Tarantino's Reservoir Dogs, Kathryn Kalinak introduces listeners not only to important composers and musical styles but also to modern theoretical concepts about how and why film music works. Throughout the book she embraces a global perspective, examining film music in Asia and the Middle East as well as in Europe and the United States.
Art today is defined by its relationship to money as never before. Prices of living artists' works have been driven to unprecedented heights, conventional boundaries within the art world have collapsed, and artists now think ever more strategically about how to advance their careers. Artists no longer simply make art, but package, sell, and brand it. Noah Horowitz exposes the inner workings of the contemporary art market, explaining how this unique economy came to be, how it works, and where it's headed.
"Good Book but would benefit from new narrator"


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In this first update on the Lotus Kids' Club, we wanted to take this opportunity to share with you Stephen Mojica's experience at LKC. He started as a volunteer, but have since become one of the main leaders at LKC. We hope you enjoy reading his transformative story.
From Team Senhoa
"I have been with Senhoa's Lotus Kids' Club for just over a year. I have been in Siem Reap for almost 2 years. It has been wonderful working with the dedicated folks of Senhoa, both Westerners and Khmers. There are challenges of course, yet the success of the program due to the hard working Khmer staff far outweigh those challenges. Watching the children grow and learn and seeing the joy on their faces as they gain knowledge and have fun is almost indescribable. As many people coming to Cambodia my goal was to help the people in any way that was most useful. I was lucky to eventually find a place that made the best use of my knowledge and experience, almost 25 years working with children and families. Thank you Senhoa.
My initial role was to help set up the preschool space, add to the learning materials and teach the teachers about early childhood development/education in the pre-school program. I have also been involved in the development of the Community Afternoon Program, which serves children 3-18 year olds. I help with the decision making and general direction of LKC. However let me state that the director, Sophy, is quite capable and is a good problem solver who has great ideas and vision. The teachers also are amazingly fast learners and have been accepting of this 'new' way of teaching and working with children. Naturally skeptical at first of implementing these 'barang' ideas regarding children they have come to accept and even embrace the methods after seeing positive changes in the children.
And of course for all of us we are doing the work to help the children and the families of this community that so desperately need support. So let me give some examples of our work.
I've watched so many of the children grow and learn. On her 1st day one girl just stood by the door and sobbed. The next couple of days she gradually moved closer, observing the action. By week's end she was cautiously participating. In the next several weeks she would mostly play alone, eventually she joined others in play. She didn't seem to talk or smile though. This gradually changed after a few months and now she's made friends, she'll sing songs, and often will flash smiles. She's bloomed thanks to the patience and support of the teachers. She's a bright, organized kid who will attend the best primary school in the Fall. A tough school to get into but accomplished through Sophy's thoughtful persistence. My guess is she'll excel.
There's one little guy who was a challenge not wanting to participate in activities, starting conflicts with other kids and generally vying for attention with negative behavior. He seemed to have a face of anger and sadness. It took a little time but this is the kid now who is the 1st to help clean up at program's end. And I love his boisterous laugh. He's still a bit of a wise guy though now it's not mean spirited but joyful. It reinforced my beliefs about young children and how they gain confidence and make appropriate choices if they are in the right environment with caring and supportive teachers. He will also attend school in the Fall and I have no doubt he'll be a willing learner.
I think about the 2 little guys who were in conflict it seemed constantly. After weeks of appropriate support and intervention these 2 guys are the best of buddies, of course with occasional conflicts but usually easily resolved. They are the 2 kids that are constantly on the move and together find ways to use materials and equipment creatively. I wish I knew what they talk to each other about, they seem to be always jabbering about something as they play. These kids have shown me once again that my ideas may be ok but they have their own agenda. I brought in pieces of hose and funnels for the water table thinking they'd be great to pour the water through. They used them as a telephone line talking and listening to each other through the hoses and funnels and laughing hysterically. They both can be focused on an activity for long periods now also, one prefers building w/ legos, the other likes puzzles. They are fun to watch. They will continue in our pre-school program for another year.
These are just a few examples of the wonderful work the teachers are doing. In the pre-school program our goals are to get the children ready to learn, ready for school. We want them to have a thirst for knowledge, the confidence and persistence to succeed and a belief that they are competent, valued individuals. The belief that they can make a difference in their lives and in the world is what we try to instill in them.
The Community Afternoon Program has become a successful and popular program. Lately we will have up to 40 kids attending a session. We struggled at first trying to figure out how can we make this work with such a large age span, 3-18. After many discussions and experimenting with different ideas we have developed a program that can address the needs of the varied aged kids. I admit I was always reluctant to work with older children but these kids have taught me how much fun and satisfying that work can be.
I am truly impressed with the older kids. Their creativity, intelligence and talents are a wonderful surprise. There are several kids that show real artistic abilities. We've recruited a few of those kids to help lead activities for the kids. One young girl around 12 or 13 has lead a craft project bringing in her own idea. We are trying our best to support and encourage these children as they all live in challenging conditions and live hand to mouth with the real possibility of not having enough to eat. Yet these kids are thoughtful, caring and still have a zest for life. I think and hope we are providing a way to express themselves or at the very least learn about who they are and what potential they have. I'm talking about all the kids not just the artistically talented ones but the kid who masters the hula hoop or completes a complicated puzzle. I hope we provide experiences that boost self confidence and lead children on a path to success in whatever they endeavor to accomplish. In any case big kids are fun.
Recently the teachers began teaching cooking one day and sewing another couple days. The teachers started these sessions after brainstorming different ideas. They just took off with the ideas which are popular and clearly a success, we may need another sewing machine soon.
After a year my role with LKC is changing. The teachers are well equipped to run the programs without my direct support. I will continue to teach about childhood development/education introducing more in depth concepts. I will continue to be involved in the planning and decision making. I have already introduced the practice of supervision for the teachers. And I have started and will continue to teach Ratha, the Social Worker, the principles and challenges of Social Work. I will spend more time enriching the programs including the professional and educational development of the staff. Perhaps I will eventually work myself out of my job. Sustainability is the mantra here and it will be a good thing.
Please understand the teachers have little if any formal training in teaching young children. They are caring and willing to learn and as I said do well with the children. Ratha, who also teaches, is the designated Social Worker, though with very little professional training. Fortunately he seems to have a natural affinity for Social Work. What I mean by that is that his sensibilities and demeanor seem to be in line with Social Work principles. He seems to gain rapport easily with parents and appears non-judgemental in his manner. He is great with the kids, caring, calm, gentle but firm. So you may wonder how do I know this considering I do not understand Khmer. Well communication is about 90% non-verbal. Also I see him interact with parents and kids, the kids especially just appear to trust him. At the monthly parent meeting/rice giveaway he always seems to get the parents laughing at the start of his talk. You can learn some of those basic Social Work skills but it's good to have some naturally.
Let me close by commending the great working relationship I have with Debra, the Country Director. Her hard working ethic, caring and dedication to the success of LKC has made my job easier and inspired me to give my all. Deb is so very supportive with a perspective that is most useful. She is a bright and lovely young women with many talents. I also have to commend Lisa and Anh, the folks who make it all possible from thousands of miles away. I feel so very supported and welcomed in my work with Senhoa. Their hard work and dedication to the families and too kind words regarding my work are also an inspiration and greatly appreciated. Yes I am lucky to be a part of Senhoa, thanks.
Stephen Mojica Senhoa LKC Project Consultant"
In early 2013, Senhoa carried out vigorous Monitor and Evaluations (M&Es) of our programs in Cambodia to ensure that they were delivered to the service users' satisfaction, as well as adhered to our core mission. Today, we share with you here our M&E results for the Senhoa Jewelry Program and their follow-ups.
The Senhoa Jewelry Program (lovingly named OOH – Our Own Hands) was initially conceptualized as a shelter-retention program. Very early on when we did our needs assessment, it was decided that a vocational training program was needed where the women could gain instant skills and quickly have access to income-generating opportunities, all while they were receiving social and therapeutic services from our shelter partners. Jewelry making and beading were chosen for ease of skill acquisition, as they required little to no education. This was befitting because many of the women in the program lacked formal education and literacy.
During the M&E sessions for the OOH program, there was an overwhelming request for full time employment from the service users. Many of the women in the program expressed a desire for viable employment and an opportunity to enter into full-time work as Artisans.
To respond to these concerns, over the past six months, the OOH program has functioned as a training and transition program to recruit and prepare Trainees to become Artisans for Senhoa Social Enterprise. At the end of the program, Trainees will have a command of basic to intermediate jewelry making skills and knowledge about being good employees. The training period has been used to transition Trainees/Artisans from "service users" into "full-time/part-time employees" for Senhoa Social Enterprise.
On January 1, 2014, we officially started Day 1 of the social business in Cambodia. Our former service users are now full time and part-time employees of the social enterprise, with access to an array of employee benefits and entitlements like access to a health fund, sales bonuses, annual leave and compassionate leave. Furthermore, the artisans work in a safe and secure environment with fair wage salary and educational opportunities. And last but not least, proceeds from the sale of Senhoa jewelry go back to supporting Senhoa Foundation's community development programs in Cambodia.
On the other end of the spectrum, Senhoa Social Enterprise is now able to focus on designing, manufacturing and retailing high quality fashion accessories for the Senhoa brand, the OOH by Senhoa brand (a lower-priced line available for sale in Cambodia), and partner labels. Our dream is to be able to have our jewelry sold around the world in department stores, to be able to subcontract to make jewelry for private labels and most importantly, to be able to provide jobs for vulnerable women. We do this with the unfailing belief that access to dignified and safe employment is the most powerful armor to protect women from exploitation and human trafficking.

subset: commoncrawl


text:
A computerized method for automatically generating a grid-based derivative of a non-gridded cell library of an integrated circuit design comprises the step of determining at least one valid position of at least one wiring element of a circuit of the first cell library, wherein the at least one valid position fulfills all technological design rules and wherein the at least one valid position fits into the second grid format. The method can also be used for automatically transforming a first cell library of an integrated circuit design having a first grid format into a second cell library having a second grid format or for automatically analyzing a grid-based cell library of an integrated circuit design in view of the circuit quality regarding technical design rules.
1. A method for designing an integrated circuit, the method comprising:
using a computer for providing a circuit description;
providing a plurality of cells comprising pre-determined circuit parts, each cell having at least one circuit pin providing electrical connection from the cell to a wiring element;
forming a placement layout of cells from said plurality of cells that represents said circuit description and satisfies pre-determined technological design rules, wherein each cell within the placement layout comprises a pin region within which said at least one circuit pin may be legally connected to a wiring element according to said technological design rules;
providing a routing grid for designing routing paths of interconnections between cells;
identifying an offending cell of said plurality of cells within said placement layout wherein said pin region of said offending cell does not legally align with a location on said routing grid;
prior to performing a routing of interconnections between cells in said placement layout, moving the location of said offending cell so that said pin region of said offending cell is legally aligned with said routing grid while continuing to satisfy said technological design rules, wherein said routing grid is characterized by a routing grid spacing and said placement layout is arranged on a placement grid having a placement grid spacing that is different than said routing grid spacing, and determining a greatest common divider of said placement grid spacing and said routing grid spacing.
2. The method according to
3. The method according to
4. The method according to
identifying a plurality of possible legal offset values for the location of said offending cell so that said at least one circuit pin in said pin region may be legally connected to a wiring element according to said technological design rules; and
selecting a best set of legal offset values from of said plurality of possible legal offset values in accordance with a wiring cost function.
5. The method according to
6. The method according to
7. The method according to
8. The method according to
9. A computer program product comprising a non-transitory computer-readable recording medium having computer-readable program code embodied therein, wherein the computer-readable program code performs the steps of:
using a computer providing a circuit description;
providing a plurality of cells comprising pre-determined circuit parts, each cell having at least one circuit pin for providing electrical connection from the cell to a wiring element;
forming a placement layout of cells from said plurality of cells that represents said circuit description and satisfies pre-determined technological design rules, wherein each cell within the placement layout comprises a pin region within which said at least one circuit pin may be legally connected to a wiring element according to said technological design rules;
providing a routing grid for designing routing paths of interconnections between cells;
identifying an offending cell of said plurality of cells within said placement layout wherein said pin region of said offending cell does not legally align with a location on said routing grid;
prior to performing a routing of interconnections between cells in said placement layout, moving the location of said offending cell so that said pin region of said offending cell is legally aligned with said routing grid while continuing to satisfy said technological design rules, wherein said routing grid is characterized by a routing grid spacing and said placement layout is arranged on a placement grid having a placement grid spacing that is different than said routing grid spacing, and determining a greatest common divider of said placement grid spacing and said routing grid spacing.
10. The computer program product according to
11. The computer program product according to
12. The computer program product according to
identifying a plurality of possible legal offset values for the location of said offending cell so that said at least one circuit pin in said pin region may be legally connected to a wiring element according to said technological design rules; and
selecting a best set of legal offset values from of said plurality of possible legal offset values in accordance with a wiring cost function.
13. The computer program product according to
14. The computer program product according to
15. The computer program product according to
16. The computer program product according to
1. Field of the Invention
This invention relates generally to the field of integrated circuit design technology and more specifically to methodologies for routing the interconnections between components of an integrated circuit.
2. Background
Microelectronic integrated circuits (ICs) consist of a large number of electronic components that are fabricated by layering several different materials on a silicon base or wafer. The physical design of an IC transforms an abstract circuit description into a geometric description, which is known as "layout" and which consists of a set of planar geometric shapes in several layers. The objective of physical design is to determine an optimal arrangement of devices in a plane or in a three dimensional space, and an efficient interconnection or routing scheme between the devices to obtain the desired functionality. Since space on a wafer is very expensive real estate, algorithms must use the space very efficiently to lower costs and improve yield.
The physical design of a microelectronic IC commonly is an automated optimization process using digital computers and specialized Computer Aided Design (CAD) tools. Automation of the physical design process has increased the level of integration, reduced turn-around time and enhanced chip performance.
A generated layout has to be checked to ensure that it meets all of the design requirements. The result of this check is a set of design files in a particular unambiguous representation known as an intermediate form that describes the layout. The design files are then converted into pattern generator files that are used to produce patterns called "masks" by an optical or electron beam pattern generator.
For the physical design of ICs, prefabricated elements are used that provide combinatorial or storage functions. These elements are called cells (or types). A collection of different cells forms a library. The usage of a cell in a design is referred to as instance or circuit. If most of cells have the same height and connect their power through abutted placement in circuit row, the cells are called standard cells and the design style standard cell layout.
A particular design element of an IC is a so-called "pin" which refers to a physical or logical access terminal to a cell and circuit. An example for a pin is an inverter having one input and one output pin.
The mentioned instances of an IC are interconnected or routed in accordance with the logical design of the circuit to provide the desired functionality. Hereby the various elements of the circuit are interconnected by electrically conductive lines or traces that are routed through vertical channels and horizontal channels that run between the cells.
The whole design process consists of the following three design phases namely Partitioning, Floor planning and placement, and Routing:
1. Partitioning—A chip may contain several million transistors and therefore the layout of the entire circuit cannot be handled in a reasonable amount of time using the currently available computation power. Therefore the layout is partitioned by grouping components into blocks such as sub circuits and modules. The output of partitioning is a set of blocks, along with the interconnections required between blocks. The set of interconnections and connected objects is referred to as a "netlist".
2. Floor planning and placement—This step is concerned with selecting good layout alternatives for each block of the entire chip, as well as between blocks and to the edges. Floor planning is a critical step as it sets up the ground work for a good layout. During placement, the blocks are exactly positioned on the chip. The goal of placement is to find a minimum area arrangement for the blocks that allows completion of interconnections between the blocks in such a way that they obey technology constraints. The placement must be legal, i.e. have no overlaps and must meet e.g. technology constraints.
Placement is typically done in two phases. In the first phase, an initial placement is created. In the second phase, the initial placement is evaluated and iterative improvements are made until the layout has minimum area and conforms to design specifications.
3. Routing—The goal of a router is to complete all circuit connections while trying to use the shortest possible wire length. Routing is usually done in two phases referred to as "global routing" and "detailed routing" phases.
During the global routing, connections are completed between the proper blocks of the circuit disregarding the exact geometric details of each wire and terminal. For each wire, a global router finds a list of channels that are to be used as a passageway for that wire. In other words, global routing specifies the loose route of a wire through different regions of the routing space.
After the global routing, the global wires have to be legalized, namely by connecting them to off-grid contact pins and maybe by moving the global wires around off-grid areas that have to be blocked to prevent not allowed short circuits or other not allowed electrical connections of the underlying circuit layout (so-called "blocking areas"). However, this legalization step is rather complex and thus computationally extensive.
In addition, IC chips typically have several metal layers upon which the wires are routed with the horizontal wires routed on different layers than the vertical wires. An electrical connection between two nets on adjacent layers is implemented using a so-called "via" which is an etched hole in a substrate's oxide for allowing a conductive path to extend from one layer to another layer of the underlying IC chip, that can be used e.g. for conducting power (so-called "power via") or even signals. The routing program must therefore produce a list of horizontal and vertical segments for each net, connected by the mentioned vias, all of which have to be conformal with the underlying technology requirements, also known as 'ground rules', for wire spacing and wire capacity.
Since the placement process may produce a non-routable layout, the chip might need to be replaced or re-partitioned before another routing is attempted. The whole design cycle is conventionally repeated several times to accomplish the design objectives. The complexity of each step varies depending on the design constraints as well as the design style used.
For the above mentioned wiring (i.e. designing the electrical connections between the blocks) it is well-known to utilize so-called 'Gridded Routers'. The basic aspects of grid-based routing are described in a white paper of Cadence Design Systems, Inc., San Jose, Calif., USA published in 2004 and entitled "Routing Requirements for the Nanometer Era".
Grid-based routers superimpose a virtual 'mesh'-like template (the so-called "routing grid" or "wiring grid") over the routing area of the design with evenly spaced tracks, or grids, running both vertically and horizontally across the design area. Every vertical and horizontal grid intersection point on the mesh is maintained as a pointer in the memory of an underlying computer, and any routing operation that is performed must be cognizant of all the grid points in the design as a whole and aware of any trade-offs, timing, congestion, design rule check (DRC), etc. involved with the specific operation before completing it. Most of the presently known routers are grid-based and only the pin-access is usually non-gridded. The reason is that a true gridless router would need a nearly infinite search space for possible wiring lines thus revealing huge run times even with small designs. On the other hand, in the case of grid-based routers, the larger the design grows or the smaller the process geometry or space between grid points becomes, the more grid points are needed to be allocated in memory, and therefore, the more time it will take for a gridded router to perform any task.
Further to the above mentioned white paper, in an article entitled "Routing for Complex SoC Designs" and being published by Synopsys, Inc., in 1999, the above described design planning and routing, including the mentioned floor planning, is disclosed in greater detail. This article, on page 5, includes a comparison of grid-based and non-grid-based routing algorithms.
In particular, in the field of Very Large-Scale Integrated (VLSI) circuit designs, in the past, the above mentioned gridded routers have been applied to circuit structures which are a multiple of a uniform grid and insofar fit into or match with the router's grid. However, recently developed chip technologies like the known Cu based 65 nm process technology require that only ground rules have to be considered. As a consequence, structures like contact pins or the above mentioned blocked or blocking areas are 'gridless' data and thus cannot be aligned with a simple routing grid. In addition, the grids for the above described placement and routing processes comprise differing offsets, i.e. these grids cannot be aligned with each other.
There exist prior art approaches (see above two citations) according to which the routing is accomplished on a gridless basis wherein interconnections are constructed without any geometrical restrictions. However, this gridless routing does not have the above described algorithmic advantages and is by a factor 4 slower than a grid-based approach.
Furthermore, the above described legalization step that is executed after the global routing, requires a computer-extensive calculation of the pin access of the contact pins and has to be executed for each single pin.
Although gridded routers are known for their relatively high speed, they lack the flexibility required for the above mentioned complex VLSI designs.
Another drawback of the grid-based routers (see above mentioned Cadence White Paper, Sec. 6.1.1) is that the position of the pre-described vias disadvantageously has to be fixed prior to the routing.
The invention is based on the objective to provide an integrated circuit routing methodology that enables a gridded wiring based on non-gridded circuit information, in particular a non-gridded circuit library.
This objective always comes up when a chip manufacturer wants to use existing libraries of standard cells of a concrete CMOS technology or similar technologies.
The objectives of the invention are solved by the features of the independent claims. Further advantageous arrangements and embodiments of the invention are set forth in the respective subclaims.
According to a first aspect of the present invention, at least one existing non-gridded library of standard cells is transformed or translated into a grid-based copy or derivative of the non-gridded cell library. This grid-based copy or derivative can be used by a gridded routing process or gridded router with the above mentioned advantages.
According to a second aspect, for the transformation or translation of a non-gridded cell library into a gridded copy or derivative thereof, legal positions of pins are determined wherein these legal positions are those positions which fulfill all technical design rules, e.g. these positions do not result in a short circuit or the like. These positions in addition have to fit into or match with a routing grid used by the router.
It is emphasized that the finding of a legal position in both the x- and y-direction, which even fits into a given grid structure, is rather difficult to achieve.
According to a further aspect, the above described determination or optimization of off-grid pin access wiring data is done in advance, i.e. prior to the following grid-based routing process. As a result, the above mentioned advantages of a grid-based routing are still provided.
According to a further aspect, an on-grid pin location can be located on a different layer, if beneficial. In this case, a legal position for the required via can be determined using the methodology according to the present invention.
According to another aspect of the present invention, even in cases where a legal position of a pin cannot be found at all, the legal validity and suitability of a combination of a book and related offset value can be determined based on a cost function.
According to still another aspect, the methodology of the present invention can also be used to analyze a non-gridded cell library in view of the possibility to find legal interconnections at all for a grid-based copy or derivative thereof in order to get corresponding quality-related information of a grid-based version of the library.
According to still another aspect, in cases where one or more cells cannot be interconnected at all, the present invention provides even an approach to overcome such problems.
According to yet another aspect of the invention, a method is provided for designing an integrated circuit, the method comprising:
providing a circuit description;
providing a plurality of cells comprising pre-determined circuit parts, each cell having at least one circuit pin for providing electrical connection from the cell to a wiring element;
forming a placement layout of cells from said plurality of cells that represents said circuit description and satisfies pre-determined technological design rules, wherein each cell within the placement layout comprises a pin region within which said at least one circuit pin may be legally connected to a wiring element according to said technological design rules;
providing a routing grid for designing routing paths of interconnections between cells;
identifying an offending cell of said plurality of cells within said placement layout wherein said pin region of said offending cell does not legally align with a location on said routing grid; and
prior to performing a routing of interconnections between cells in said placement layout, moving the location of said offending cell so that said pin region of said offending cell is legally aligned with said routing grid while continuing to satisfy said technological design rules.
Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
Skilled artisans will observe that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures are exaggerated relative to other elements to help to ease understanding of embodiments of the present invention.
A typical integrated circuit (IC) design flow uses so-called "standard cells" as basis for building circuits. Such standard cells are pre-designed circuit parts that the CAD tools use to assemble larger circuits. A standard cell is understood to be a specific logic function generally associated with a larger standard cell library having many (e.g. several hundred) individual standard cells which are ground rule compliant themselves. The cell-based design relies on a building-block infrastructure based on standard libraries of such cells. Suitable sets of such digital cell libraries contain several hundreds of cells.
Such a library is depicted in
As known in the art, a cell-based IC is formed by selecting a plurality of cells that represent components having different characteristics from one or more cell libraries, determining interconnects for the selected cells, and then placing and routing the interconnected selected cells to form the IC. For instance, groups of cells may be interconnected to function as flip-flops, shift registers and the like.
The above design process is conventionally described in terms of logic description, synthesis of that logic, and then placement and routing of the synthesized logic.
The end result of the logic design is a netlist providing interconnections to boxes representing logic elements selected from a library. Upon completion of the logic design, a physical design process must then be performed to translate the abstract logic design into its physical realization on the chip. The physical design process consists of placing boxes wherein physical realizations of the library cells are used to place the boxes on a chip image.
Every circuit has a set of constraints it must meet like timing constraints which specify when clock and other signals actually arrive and when they are required to arrive. Additional constraints include electrical constraints which limit the amount of capacitance on any net and the maximum amount of slew time that can be tolerated. Finally there are other technology rules that constrain the design, for instance that places boxes must not overlap. A design is considered to be legal if it meets all the design constraints.
It is the task of routing (also referred to as "wiring") to arrange the wires on the chip image so that connections among the pins match the logical connections. Electrical connections of individual components on ICs are established using conducting paths (called "wires" or "nets") between terminals of components which are to be connected. Automatic routing schemes are used to determine these conducting paths.
IC chips typically have several metal layers commonly designated at M1, M2, M3, etc. upon which the wires are routed with the horizontal wires routed on different layers than the vertical wires. As described beforehand, electrical connection between two nets on adjacent layers is implemented with "vias". The underlying routing process must therefore produce a list of horizontal and vertical segments for each net, connected by vias, all of which conform to the technology requirements for wire spacing and wire capacity.
In most cases, the wiring process is executed after the chip placement and thus the wire end points, also commonly known as 'terminals', are known and fixed. Using physical design algorithms as discussed above, each cell placement is conventionally represented in the form of a list or table including locations on the chip and identifiers of the cells that are assigned to the respective locations. Routing processes therefore attempt to completely route the wires among the end points to avoid congestion. However, in some instances, wiring may be performed concurrently with placement, particularly since the placements in the design can to some extent avoid wiring congestion.
For more complex designs like the above mentioned VLSI designs, there are typically at least four distinct layers of conducting medium available for routing, such as a poly-silicon layer P1 and three metal layers M1-M3. These at least four layers are all used for vertical and/or horizontal routing. Hereby it is common practice to route each conducting path by using one or more of the distinct layers M1-M3 and P1, with one layer of a pair being reserved predominantly for connections running along the "x" direction and the other layer for connections running in the orthogonal or "y" direction. Some of the layers, such as the metal layers M1-M3, are exclusively used for interconnection of components wherein the poly-silicon layer P1 may have a dual role, such as forming the gates of transistors as well as for interconnection of components.
Turning now back to
As already mentioned, the library 100 is either a non-gridded one i.e. the circuit elements and included wiring included in the standard cells of the library 100 are designed without using a grid, or the offset of the underlying grid (so-called placement grid) is assumed to be different from the offset of the routing grid later used in the grid-based router. The mentioned circuit elements, in other words, are not aligned with the lines of a grid.
In order to allow the use of such a non-gridded library 100 in a grid-based router, the non-gridded library according to the present invention is modified, preferably transformed or translated, in advance, i.e. prior to the use in the grid-based router, to a gridded copy or derivate 110 thereof. This transformation is mainly based on a procedure 105 by which legal positions of particularly the mentioned vias are determined based on given design rules. An example of such a design rule is the avoidance of a short circuit, e.g. caused by a via between two metal layers like M1 and M2 or M2 and M3.
As a result, the modified library 110 can be used in a grid-based router. The transformation of the library from the non-gridded one 100 to the gridded one 110, based on the inventive method described in the following in more detail, can be advantageously performed in a relatively short time of about and in even less than 1 min.
As mentioned hereinbefore, gridded routers divide the routing area in a uniform grid for every metal layer. As an example,
As already stated above, although the main advantage of grid-based routers is that they can handle very large designs and therefore current commercial routers for standard cell designs are gridded, this approach may waste real estate, for example with a wire that only needs 1.2 times the grid. As a consequence, they cannot efficiently handle variable width and spacing of wires or other structural elements of the design. In particular with the advent of 0.25 micron and below technologies, variable width and spacing is required for long wires to satisfy noise, delay, cross-talk or signal integrity issues.
In addition to the above described transformation between a non-gridded and grid-based library, there exist further scenarios where the present invention can be applied correspondingly. Only exemplarily it is referred to the already mentioned 65 nm technology based IC design process where the mentioned placement grid comprises an offset value (i.e. the distance between neighboring grid lines) of 250 nm and where the routing (wiring) grid comprises a differing offset value namely 200 nm.
As a consequence, in such a scenario the described circuit pins or pin areas (see
Turning back to
The following described
In the upper part of
Circuit pins of a standard cell 300 are typically located on the mentioned 'M1' layer. The problem of the differing grids (placement and routing grid) only exists in the x direction. In case of the y direction, the placement grid is always a multiple of the routing grid.
Another additional circuit design element is a blockage area 415 caused by power wiring which is therefore not available for other design elements.
Further additional design elements are a circuit pin 405 being aligned to the x-grid but not the y-grid and a segment 410 which is located on an intersection point of the underlying routing grid in a way that the mentioned circuit pin 405 becomes connected from its off-y-grid position to an entirely on-grid location. Therefore an advantageous result of the present invention is that after having applied the proposed methodology, all via positions of all instances are located on grid positions in both x and y direction.
The general concept of the methodology according to the present invention is now illustrated referring to
Turning now back to
In a first step 450, the greatest common divider d of the placement grid and the routing grid, which is 50 nm in the example illustrated in
The split drawing in
In the present embodiment, it is assumed that the grid-less circuit library itself includes an own grid called "placement grid" which is also a tool to be used in the overall IC design process as it defines the on-chip interconnects which are the bottleneck in determining circuit performance. It is assumed that the placement grid and the routing grid comprise a differing offset value, i.e. one of these grids cannot be fitted into the other.
The present transformation process is based on the general assumption that the offset of the placement and routing grid is different. Therefore, according to a first step 500, the offset values of the placement grid ('pg') and the routing grid ('rg') are input or obtained. Using these two offset values, in the following step 505 it is determined if the two offset values are different or not. If the comparison step 505 reveals that they are not different, the offset is set to value '0'. If the comparison step 505 reveals that the two offset values are different, then all possible offset values between the two grids are determined 510.
Only as an implementation example, for a placement grid with an offset value of 250 nm and a routing grid with an offset value of 200 nm, the four possible offset values are 0 nm, 50 nm, 100 nm and 150 nm. In the case that the placement and the routing grid (i.e. their offset values) are identical, the offset will always be zero.
The following steps 525 to 535 represent a first loop 520 with n=1, 2, . . . , where n is designating a circuit number or counter. In step 525, the offset value of the placement grid in x-direction for a current circuit n is gathered or input. Based on the result of the division of the x-offset value of the placement grid by the x-offset value of the routing grid, for the current circuit n, an offset value is selected 530. The offset value for the current and each other circuit n included in the loop is then stored 535 as a tuple [cell, offset].
Starting with the existing placement of the circuit elements within a circuit, each circuit is assigned a unique combination of the two properties cell and corresponding offset, in the preferred embodiment using the mentioned data tuple. The offset is calculated as modulo of the division of the x-coordinates of the placement grid and the routing grid, wherein a possible reflection at the y-axis of the grid may be taken into consideration. The present loop runs on the circuits of a netlist.
The following steps 545 to 600 of the present procedure are part of a second loop 540 which counts the cell number c starting with c=1. In addition, this second loop 540 includes five additional (inner) loops starting with corresponding steps 550, 560, 570, 575 and 590. These further loops are separated from each other by the shown solid lines.
In step 545, the design data of a current cell c are gathered or input. Based on the design data of the current cell c, with step 550 a first inner loop is started where the following steps 560 to 600 are executed for each offset of the possible offset values 0, 50, 100 and 150 according to the above described preferred embodiment using counter o. With next step 560, the next inner loop is started where the following steps 561 and 562 are executed for each pin with pin counter p=1 . . . m of the current cell c.
In step 561, a list V(p) of all ground rule compliant via locations v(p,1), v(p,2), . . . , v(p,k) with X-coordinate on grid and shifted by an offset value according to the current offset counter o is computed. In the following step 562, based on these via locations v(p,1), v(p,2), . . . , v(p,k), a via cost function cost(v(p,i)) is defined as the amount of additional wiring to connect pin p to via location v(p,i). The list V(p) is then sorted in such a way that for all i=1 . . . n−1 the following condition is fulfilled:
The following block 565 comprises a number of steps. In a first step, a logical variable 'best viaset' of the cost function is set to the logical value 'unknown'. Then an initial viaset (v(1,0), . . . , v(m,0)) is added to the above described list of viaset candidates. The viaset cost is defined as the sum of the costs of the vias contained in the candidate list.
With step 570, the next inner loop starts where the following steps 575 to 585 included in this inner loop are only executed as long as the current list of viaset candidates is not empty. With step 575 the next inner loop starts where the following steps 576 to 578 are only executed as long as the following condition is fulfilled: The current viaset in the list is checked if the condition is fulfilled that vias are pair-wise ground rule compliant and that vias v(p,i) and v(q,j) are not compliant.
In step 576 two new viasets are created by either replacing v(p,i) by v(p,i+1) or v(q,j) by v(q,j+1) in the current viaset. For each new viaset it is then checked 577 if the logical variable 'best viaset' is set to 'unknown' or if the value of the cost function of the best viaset is higher than the cost value for the new viaset. If so, the new viaset is appended to the list of viaset candidates. At the end of the present inner loop, in step 578 of the present inner loop the first viaset in the list is assigned with the logical value 'not compliant'.
In the following step 580, it is checked whether the first viaset is ground rule compliant, and whether the logical variable 'best viaset' is set to 'unknown' or whether the best viaset is known and has a higher cost value than the first viaset. If one of the two alternative conditions is fulfilled then the first viaset in the list is assigned as 'best viaset'. The inner loop starting at step 570 is then finalized by removing 585 the first viaset from the list of viaset candidates.
At block 590, the last of the mentioned inner loops begins. It is first checked if the logical variable 'best viaset' is set to 'unknown', i.e. no ground rule compliant viaset has been revealed by the previous steps 540 to 585. In this case, the current tuple [cell, offset] is marked as 'offending'. Otherwise the following two steps 595 and 600 are executed.
In step 595 a pin with a minimal pin area located on layer M2 is determined which embraces a via pad at via location v(p,i) and a wire to the nearest on-grid (intersection) point that is shifted by an offset value according to the current offset counter o. Finally, in step 600 the newly determined pin and a via at location v(p,i), together with a segment from v(p,i) to pin p and from v(p,i) to the nearest grid point is stored as "access wire".
The use of a cost function or an objective function in solving an optimization problem in which the cost function is minimized or maximized is known in the art. Such a cost function based optimization approach seeks to minimize or maximize a real function by systematically choosing the values of real or integer variables from within an allowed set. This problem can be represented in the following way:
Given: a function f: A→R from some set A to the real numbers Sought: an element x0 in A such that f(x0)�f(x) for all x in A ("minimization") or such that f(x0)�f(x) for all x in A ("maximization").
However, the use of such a cost function for the physical design of an IC is not known in the art. Applying such a cost function to the present field of routing interconnections in an IC design, the function f represents the total wiring interconnection length of an underlying circuit cell or book which has to be minimized but meeting the above described 'legal validity' and 'suitability' requirements of the underlying design being routed.
Typically, A is some subset of the Euclidean space Rn, often specified by a set of constraints, equalities or inequalities that the members of A have to satisfy. The elements of A are called feasible solutions. The function f is called an objective function, or cost function. A feasible solution that minimizes (or maximizes, if that is the goal) the objective function is called an optimal solution.
The domain A of f is called the search space, while the elements of A are called candidate solutions or feasible solutions. Generally, when the feasible region or the objective function of the problem does not present convexity, there may be several local minima and maxima, where a local minimum x* is defined as a point for which there exists some •>0 so that for all x such that
the expression
holds, i.e. in some region around x* all of the function values are greater than or equal to the value at that point. Local maxima are defined similarly.
The above cost function can be based on a "half-perimeter" wire length computation and be used in the present context in order to model the possibility of wiring given book-offset combination. As in general, the higher the calculated costs are, the lower are the possibilities to find a wiring for the combination. As an example, combinations for which there does not exist a legally permitted viaset, the revealing costs are unlimited high. In the following step, all movable i.e. non-fixed circuits or circuit elements are moved or newly placed in a way that the total costs of both the current target function and the costs of the current book-offset combination are minimized.
An exemplary pseudo code using the above cost function in the present field is
The present invention can be implemented either in a router or separate placement and wiring tools.
Furthermore, the present invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.
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French Bench
February 12th, 2015 | by Madam Rosmerta
Materials: Sultan Luröy, 6 slats for the seat, 4 slats for the construct Sultan Lade, several remaining pieces for the
February 12th, 2015 | by Madam Rosmerta
Materials: Sultan Luröy, 6 slats for the seat, 4 slats for the construct Sultan Lade, several remaining pieces for the
February 4th, 2015 | by Shannon George
Materials: Two RAST 3-drawer chests I have always wanted built-in bookshelves. I had intended to do the typical Billy Bookcase
January 27th, 2015 | by CaLynn
Here are the basics for adding a seat to the BEKVÄM step stool: 1. Cut a board and piece of
January 22nd, 2015 | by Lydia C.
I wanted a modern, space saving, unique, floating credenza. Scoured the internet for some cool ideas and decided on the
January 21st, 2015 | by SchilderScholte architects
Made of hundreds of IKEA Lack tables, this 32 meter long 3.2 meter high office space divider designed for a
January 20th, 2015 | by Jules IKEAHacker
We used 4 LIDINGÖ upper cabinets and simply built a base for them to sit on then added a countertop
January 15th, 2015 | by Jules IKEAHacker
One post about two EKTORP getting custom dyed slipcovers. Love the bold bright colours! ~ Jules Tiffany's indigo Materials:
January 12th, 2015 | by Karen Stewart
Materials: Two MOLGER bathroom floor decking tiles We needed a small, simple table to go next to our IKEA POANG chair
January 12th, 2015 | by Andrew W. Bain
Materials: KALLAX Insert with Door; AVSKILD Set of 4 Place Mats Tools used: Sharp pencil; Sharp modelling knife; Glue (
January 5th, 2015 | by doortje
Materials: Minna fabricX Signe cotton rugs What I did was: - cut off the shorter, knotted edges of the rugs,
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Ummm... I'm writing this review because I cannot sleep! The sounds of people getting in and out of cars the entire night in unnerving. My husband was approached by two "working" women who offered to... um, yeah. He said he was married, however one of the ladies persisted. He had to swiftly walk away. I can't wait until daybreak, i wanna leave this place so bad & I'm praying that I can get a refund. I don't understand how an owner can let his hotel be used for pimps and prostitutes. I feel like I'm in the story mode of a Grand Theft Auto video game! Tomorrow I am calling the police.
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Location: United States > California > Fresno
Business Center with Internet Access Fitness Center with Gym / Workout Room Free Breakfast Free Parking Swimming Pool Wheelchair access
Ranked #40 of 65 Hotels in Fresno
Price Range (Based on Average Rates): $
Hotel Class:2 star — Knights Inn Fresno North 2*
Number of rooms: 111
- Reservation Options:
- TripAdvisor is proud to partner with Priceline, Expedia, Travelocity, Cheap Tickets, Orbitz, TripOnline SA and Hotels.com so you can book your Knights Inn Fresno North reservations with confidence. We help millions of travelers each month to find the perfect hotel for both vacation and business trips, always with the best discounts and special offers.
- Also Known As:
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Roasted Chicken Pieces with Pears and Green Onions
This kid-friendly recipe couldn't be simpler to prepare — just sprinkle chicken pieces and sliced pears with lemon zest, lemon juice, and green onions and roast until golden and tender.
Total Time:
Level: Easy
Yield: 4 main-dish servings
Serves: 4
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- 2 lemons
- 1 bunch green onions
- 2 tbsp. olive oil
- salt
- Pepper
- 1 Chicken
- 3 ripe but firm bosc pears
- Preheat oven to 450 degrees F. Spray 15 1/2-inch by 10 1/2-inch jelly-roll pan with nonstick cooking spray.
- From 1 lemon, grate 2 teaspoons peel and squeeze 1 tablespoon juice. Cut remaining lemon into wedges. Cut white and light-green portion of green onions into 2-inch pieces; thinly slice dark-green tops. Set aside lemon juice, lemon wedges, and sliced green onion tops.
- In large bowl, stir together lemon peel, oil, 3/4 teaspoon salt, and 1/2 teaspoon freshly ground black pepper. Add chicken, pears, and white and light-green onion pieces, and toss until coated.
- Arrange chicken mixture in prepared pan. Roast 30 to 35 minutes or until juices run clear when thickest part of chicken is pierced with tip of knife and pears are fork-tender. Transfer chicken mixture to warm platter; drizzle with lemon juice, and sprinkle with green onion tops. Serve with pan juices and lemon wedges.
From: Good Housekeeping
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On June 18, 2015, Bill S-4, the Digital Privacy Act was passed by Canada's House of Commons vote. Bill S-4 was previously passed by Canada's Senate. The Digital Privacy Act includes important amendments to the Personal...more
At a Press Conference today, Satan officially announced that Hell has frozen over. He made this stunning announcement after the New York Times (NYT) reported that the baseball team with the most World Series wins in the...more
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U.S. financial markets and participants, much like other segments of the U.S. economy, are prime targets for technological hacks, intrusions, and breaches that can occur...more
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..FINRA Scrutiny
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In 1986, the car ran as part of an independent team. It won three rallies in Ireland, driven by Billy Coleman and Jimmy McRae and retired after the RAC Rally in 1986, the last time Group B rally cars competed in the World Rally Championships.
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Engineer Research and Development Center, USACE--Use of Plant Replacement and Improvement Program Account to Replace Headquarters Building
B-318897: Mar 18, 2010
Additional Materials:
- Full Report:
(202) 512-2853
Office of Public Affairs
(202) 512-4800
The Director of Resource Management for the Engineer Research and Development Center (ERDC), U.S. Army Corps of Engineers (USACE), in Vicksburg, Mississippi, in his capacity as certifying officer, has requested a decision under 31 U.S.C. 3529 on whether ERDC may use funds available in USACE's Plant Replacement and Improvement Program (PRIP) account to replace its existing headquarters building without seeking specific congressional approval. Letter from Director, Resource Management, ERDC, to Acting General Counsel, GAO, Oct. 23, 2009 (Request Letter). As explained below, we conclude that PRIP account funds are not available for the construction of a new ERDC headquarters without specific congressional authorization.
Based on the above, we agree with the Chief Counsel's position that congressional authorization should be sought before using the PRIP account of the USACE Revolving Fund for construction of a new ERDC headquarters building.
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All Answers (13)
- There's a Wald test for nested models where you can look at the effect of dropping parameters.
- Yes, you can use a Wald test in the way Mitchell mentioned. Usually, a likelihood-ratio test is the better choice.
- The Wald test has application in many areas of statistical modelling. Any time a likelihood based approach is used for estimation (e.g., logistic regression, Poisson regression, the partial likelihood of Cox's model) there are three categories of tests that can be used, 1, Wald tests, 2, likelihood ratio tests and the less common, 3, score tests. The latter test category, goes by different names sometimes, For instance the logrank test is the score test corresponding to Cox's model. The score test for logisitic or Poisson regression turns out to be quite similar to a z-test for comparing means (or t-test for large samples size).
A Wald test is distinguished by the property that it is based on the parameter estimates and their covariances (e.g., standard errors) derived using maximum likelihood or least squares (or other), whereas a likelihood ratio tests is based on the likelihood function evaluated at two points.
Wald tests and likelihood ratio tests typically yield very similar results, especially as the sample size increases.
- Julie! In Generalized Linear Models context you can verify the significance of the predictor (in regression analysis) using the Wald's test and more commonly the Likelihood Ratio Test (LRT). Both test follow asymptotically a Chi-square distribution to calculate its significance. If you prefer I can send you a spreadsheet with some example of how to calculate the LRT. Best regards.
- "Wald test" is a very general method - in fact, one of the criticisms is that you can invent lots of Wald tests for a particular testing problem and decide which one you like best. I'm sure I can invent an infinite number (well, an unending sequence) of Wald tests for any hypothesis testing problem.
I do agree with a previous responder that the (for a given frequentist model) unique Likelihood Ratio Test (LRT) may be better (the LRT is a.k.a. Wilks' Test; though Wilks and Wald share a common first letter for their family name, they seem to have had rather different personalities; Wald contributed to many fields whereas Wilks was mainly a statistician; perhaps that explains the difference in their methodologies; but in defense of Wald, his tests are more generally applicable). I hope that answers your question.
- Just to back this up with another vote, when some version of a likelihood ratio test is available, it seems the way to go. I wasn't aware that one could generate so many Wald tests, but it seems like they survive in certain statistical procedures where little else is available.
- Wald tests are more broadly applicable than LRTs or score tests. For the LRT to be applicable, you need to specify a distributional model for the data generating process, which then gives you the likelihood for the parameters, given the observed data. You cannot do an LRT without a likelihood! Suppose that you do not want to write down a full probability model for the data, but want to estimate parameters related to some moments of the distribution, most commonly, the mean of the distribution. Now, how do you test whether a particular term in the model is warranted or not? This is where Wald-type tests come in handy. The quadratic product, b' V b has a chi-square distribution with K-1 degrees of freedom (asymptotically), where b is the vector of parameter estimates and V is the estimated variance-covariance matrix for parameters, and K is the dimension of b (number of parameters).
- Under the null, Wald, LRT and Rao are asymptotically equivalent . However, if you specify the alternative, things will become quite complicated - but mostly, we do NHST...
- Wald test follows chi square distribution and may be used with normal distribution.It may be used when looking at one model for an estimate with less harm if the test fails.
- Wald test can be used to test the association between the independent variables (predictors) and the criterion variable (dependent) variable. A Wald test can be used in a great variety of different models including models for dichotomous variables and models for continuous variables.
- Wald's test is better described as a distribution free method for testing the null hypothesis that two samples come from identical populations. In other words it can indeed be used to test the influence of parameters on distribution of patients between 2 groups.
- ..From an elaborate view point Wald's statistic is a test statistic with
a known probability distribution (a chi-square distribution) that is used to test whether the b coefficient for a predictor in a logistic regression model is significantly different from zero. It is analogous to the t-statistic in a regression model in that it is simply
the b coefficient divided by its standard error. The Wald statistic is inaccurate when the regression coefficient (b) is large, because the standard error tends to become
inflated, resulting in the Wald statistic being underestimated.
- for complete information about Wald statistic, LM stat (also called Score test), and LR stat read the following chapter written by RF Engle in Handbook of Econometrics
It will give complete information and is quite easy to understand.
Best Regards,
Rajesh Sharma
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