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Editor's note: The U.S. Supreme Court ruled April 25 on three cases described in this story. Read more about the decisions.
When Scott Keller of The University of Texas School of Law joined the inaugural class of the Supreme Court Clinic last fall, one of the first things he learned was how daunting the odds were against taking a case "all the way to the Supreme Court."
But Keller and his five classmates, supervised by law professor Michael Sturley and Washington, D.C., lawyer David C. Frederick, a 1989 Law School graduate, beat those odds—more than 100 to one—in January when the U.S. Supreme Court agreed to hear the Clinic's very first case.
"Taking a case to the U.S. Supreme Court as a law student is kind of like making the BCS championship (football) game or the Final Four (in basketball)," said Keller, 25, who learned in the Clinic how to look for cases that stand a better chance of catching the Court's interest. "It's a lot of hard work to get there and it's an honor to have such an opportunity."
That opportunity to litigate at the highest level is uncommon. Most attorneys can work their entire careers without ever having that experience. It's even more unusual when the advocates are still in law school.
During its most recent term the Supreme Court agreed to hear only 78 of the 8,517 cases filed, or fewer than one percent. Of the cases selected for review this term, students and faculty in the Supreme Court Clinic and the Capital Punishment Clinic have been involved in five—an unprecedented number of active Supreme Court cases at any law school in a single term.
"It is a remarkable success for two of our clinics to have cases accepted by the Supreme Court for argument in the same semester," said UT Law Professor Eden Harrington, who oversees the Law School's 14 clinics and seven internship programs.
Capital Punishment Clinic Argues Three Cases, Assists in Fourth in Single Term
In addition to agreeing to hear the Supreme Court Clinic's case Altadis USA v. Sea Star Line, the high court announced last fall it was granting "certiorari" (or review of a lower court's decision on the merits) in three death penalty cases filed by the Capital Punishment Clinic. Assisted by students and faculty co-counsel, law professors Rob Owen and Jordan Steiker argued those cases before the Court in January and are awaiting decisions. The Clinic assisted in a fourth Texas death penalty case argued before the Court on April 18. The Court is expected to decide all four cases by the end of June.
"This is an extraordinary year in Texas death penalty litigation because the Supreme Court has accepted four cases for review, and the clinic has been involved in all of them," said Jim Marcus, an expert in death penalty litigation and professor with the Capital Punishment Clinic. "For students, it's a highly valuable experience to be part of a legal team litigating a case in the Supreme Court that will eventually form part of the Court's canon of Eighth Amendment jurisprudence."
Since 1987 when the Capital Punishment Clinic was established at the School of Law, about 300 law students have assisted in representing indigent defendants charged with or convicted of capital crimes. Students, who must also attend a weekly class in the practical skills required to defend a capital case, work at least 10 hours a week under the supervision of attorneys handling death penalty cases at trial, on appeal, or in post-conviction review.
Students perform tasks that are integral to effective defense representation, including visiting clients on death row or in local jails, interviewing witnesses, conducting other field investigations, drafting legal pleadings and helping attorneys prepare for trials, evidentiary hearings and appellate arguments.
"One of the things that distinguishes our clinic from other capital punishment law school clinics around the country is simply the accelerated pace of the death penalty in Texas," said Owen, who along with Steiker co-directs the university's Capital Punishment Center, which houses the Capital Punishment Clinic. "We have a lot more cases, there are a lot more people who are in imminent danger of being executed and students are working on cases with a certain urgency to them."
Owen said it's the steady stream of Texas capital punishment cases that allows students to gain valuable experience at various stages of the litigation process, including appellate work at the Supreme Court level.
"One of the unusual things about death penalty litigation, and one of the reasons that I was interested in it as a student and drawn to it as a lawyer, is that it is so Supreme Court focused," Owen said. "The Supreme Court still devotes a surprisingly large proportion of its docket to capital cases, so you need to be aware of what's going on at the Supreme Court and be a closer student of that body of law than you do in other kinds of practice."
Eric Harrington is a third-year law student who has worked in the clinic for three semesters and finds the range and depth of the clinic's legal training to be compelling.
"I've researched whether a certain drug interacts with another drug when talking to a physician about mitigation for one client," Harrington said. "I've done classical legal writing," he said, noting that he'd penned several memos about issues critical to clients' cases. "I've also had truly transformative client interactions on death row."
But for Harrington the culmination of his clinical experience was traveling to Washington, D.C., with his classmates earlier this year to observe Steiker and Owen in oral arguments before the Supreme Court.
"You are really on the edge of your seat," he said. "It was an amazing experience to watch our professors spar with Justice (Antonin) Scalia and Justice (Stephen) Breyer."
Second-year law student Daniel Gagarin agreed, saying the experience was more than a novelty.
"The experience will stick with me for the rest of my life. I was really moved by it," said Gagarin, who found watching the professors practice and strategize at moot courts the week before to be just as interesting as the actual argument.
Harrington said students also experienced the "life of the Supreme Court" and the personalities of the justices in a way that isn't possible from opinions or through the media.
CHIEF JUSTICE ROBERTS: How would you compare that evidence with the evidence in Penry itself?
MR. OWEN: I think, Your Honor—
CHIEF JUSTICE ROBERTS: These are closer cases than Penry, I think. You'd have to concede that, wouldn't you?
MR. OWEN: I think they are different cases, Your Honor, I'm not willing to concede that they are closer cases. I think that in, in the jurors' minds, the only conclusion that could be drawn from the evidence in these cases is that the Defendants are likely to be dangerous in the future. That is exactly the same conclusion that would have been compelled by the evidence in Penry.
JUSTICE GINSBURG: [S]uppose we think the evidence is weaker, it's still evidence of childhood abuse and mental disorder of some kind, and those are relevant mitigating factors.
MR. OWEN: Absolutely, Your Honor.
JUSTICE GINSBURG: So if your case is less strong than maybe the jury will decide it the other way. But it doesn't mean that those factors are not mitigating factors.
MR. OWEN: I couldn't agree more, Your Honor. I think it's very clearly settled by Tennard and other cases going back to 1976 that facts like a deprived or abused background or mental impairment are certainly mitigating.
More case materials:
Download Adobe Reader.
"I did not realize that Justice Breyer was such an animated person on the bench, swinging back and forth with his hand on his head leaning forward. The volleying of Supreme Court litigation is just absolutely fascinating," said Harrington, adding that Steiker had barely started his argument when Justice Scalia interrupted with a question.
Both Steiker and Owen are nationally recognized experts on death penalty constitutional law. Steiker—who joined the Law faculty in 1990 after serving as a law clerk to Supreme Court Justice Thurgood Marshall—argued the Smith v. Texas case in January before the Court with co-counsels Maurie Levin, a professor with the Clinic, and Harvard University Law Professor Carol Steiker. Owen—who has defended people facing the death penalty since 1989 and who also leads a Plan II Honors freshman seminar on the death penalty—argued the consolidated cases of Brewer v. Quarterman and Abdul-Kabir v. Quarterman with Steiker serving as co-counsel in the cases.
Smith, Brewer and Abdul-Kabir all addressed the similar question of whether the sentencing instructions given to the defendant's jury allowed jurors to consider "mitigating" evidence during the punishment phase of the trial, such as a defendant's intellectual impairments, learning disabilities, placement in special education and traumatic family background. Jurors allowed to consider such evidence, argued the Clinic's attorneys, might choose to sentence the defendant to life imprisonment rather than death by injection.
Another law student who attended the oral arguments in January was Meghan Shapiro, who plans to join the Clinic next year but as a first-year student volunteered to work on the Smith case.
"Meghan jumped in and found terrific support for an important issue in the case," Steiker said. "And that issue became a very salient one at argument, where we were asked about how the Texas courts had traditionally treated a failure to make a contemporaneous objection."
"Contributing to a case that goes to the Supreme Court is such an exciting experience that when I was doing that, I couldn't wait to finish the work for my regular classes," said Shapiro, a Virginia native who chose to attend the Law School for the opportunities to work on death penalty cases.
"It's really what motivated me to study hard, so I could do something that was current and affecting a real person and possibly affecting history," she said.
Shapiro arrived outside the Supreme Court building in the pre-dawn hours on the day of the oral arguments and stood in bitter cold temperatures for hours with more than a dozen students to ensure seats inside the Court.
"We were thrilled that the students were able to attend the arguments in the Supreme Court after working on the cases and understanding the issues from the inside out," Steiker said. "They also got to see the evolution of what we had said in our moots and how we were encouraged to reframe or change our argument. It's great for our students to see us as students, too."
Owen often tells his students that any one of them could end up arguing a case before the Supreme Court.
"You really should not assume lightly that your life's path will not lead you to that podium because it can surprise you," he reminded students recently.
Shapiro said she can imagine becoming a Supreme Court litigator.
"It becomes very real when you're actually sitting there watching people you know argue these cases," she said. "You're sitting there the whole time thinking, I guess I could have answered that question. Then suddenly you start to think, maybe I might be doing that one day."
"One of the best things that our clinic can do is allow our students to envision themselves involved in the highest levels of practice," Steiker said. "And our students come out of the clinic much better equipped to wrestle with complicated legal issues and to work with others to refine their positions and advocacy."
Steiker added that many former students are now highly successful and highly respected advocates in capital litigation.
The Court has not yet ruled on the three cases the clinic argued in January, but opinions could be issued any time before the end of the Court's 2006-2007 term in June. In recent years, the Capital Punishment Clinic, led by Owen and Steiker, has litigated two other death penalty cases before the Supreme Court and won both times.
Students in the Capital Punishment Clinic are working on another Supreme Court case, Panetti v. Quarterman, under the supervision of clinical professors Levin and Marcus. The case was argued by an attorney with the Texas Defender Service (TDS), a private, non-profit law firm that represents death row inmates. Levin works part-time as a staff attorney at TDS, where Marcus was executive director before coming to the university's School of Law.
According to Steiker, the arrival of Levin and Marcus to the Capital Punishment Clinic has strengthened the Clinic's mission.
"They have both brought invaluable experience as high-powered capital litigators to the Capital Punishment Clinic," he said, "and their efforts in these cases have been extraordinary."
The issue in the case is whether Scott Panetti, sentenced to death for murdering his wife's parents, is mentally competent to be executed. Marcus said Panetti, with a long history of severe mental health problems, has been diagnosed as a schizophrenic and doesn't have a rational grasp of why Texas intends to execute him.
Several of the students, including advanced clinic student Christina Thoda, have worked on the opening brief, which was filed at the end of February. During spring break in March, the 27-year-old student traveled with Marcus and other clinic students to death row at Texas Department of Criminal Justice's Polunsky Unit in Livingston to meet their client, Panetti, face to face for the first time.
"It's a very emotional experience talking to anyone on death row, especially someone like Panetti, who is visibly mentally ill," Thoda said. Her goal, she said, is to help inmates get a fair trial.
"Ninety-nine percent of the time, these people have not gotten a fair shake from the justice system because their previous counsel or the process has been inept," Thoda said. "They've never had anyone truly understand or fight for the issues in their cases."
Thoda helped produce a chart for the Supreme Court brief surveying the law related to competency for execution in the 38 death penalty states in the country. She said her work on the Panetti case was much more advanced than the work she did for the clinic's three other Supreme Court litigation cases this year.
"That made the experience of going to the Supreme Court the second time so much more satisfying," she said. "To see the law culminate at this level, to see the process go all the way to the Supreme Court, this is what as a law student I've been studying for. It reminds me that what I'm doing is really important and this is why I wanted to be a lawyer. When I get into the grunt work of finals, I can look back at this experience and remember why I'm doing this."
When Thoda graduates this May she will join the New York office of Fulbright & Jaworski in the firm's litigation department, where she expects to have the opportunity to do pro bono death penalty work.
Early Victory for New Supreme Court Clinic
In 1977, the law school's oldest clinic, the Criminal Defense Clinic, brought Acker v. Texas to the Supreme Court. The Court agreed to decide the case (and ruled in favor of the Clinic's client)—apparently the first time that a clinic-generated case had been accepted for review.
Thirty years later, one of the newest clinics at the law school, the Supreme Court Clinic, also scored a huge victory when the Court announced in January that it had agreed to review the Clinic's very first case.
Word of the Clinic's early success quickly heightened the allure of Supreme Court advocacy among Law students and pushed the clinic off to a strong start.
"I've already had ten 1-Ls (first-year law students) come up and ask me, 'How do you get into the Supreme Court Clinic?'" said Keller, who along with other students works with faculty and seasoned Supreme Court litigators on cases pending before the Supreme Court.
The Supreme Court Clinic meets once or twice a week, often on the fifth floor of the law library in a corner room where pictures of Supreme Court justices throughout history cover the walls. In the Clinic, students are assigned to represent real clients seeking review of lower court decisions. The cases may be in any substantive area of law ranging from transport law to the Fourth Amendment, although they are most likely to involve federal statutory issues.
Clinic faculty members retain the ultimate responsibility for a case, but students take the lead in doing the legal research, developing the arguments that will be used and preparing the initial drafts of the briefs or other documents to be filed with the Court. The Clinic also includes traditional classroom sessions to introduce students to Supreme Court practice and procedures.
In its first case, the Clinic agreed last fall to represent a Florida company, Altadis USA, which contracted with Sea Star Line to carry a sealed container of cigars and cigar bands from San Juan, Puerto Rico, to Tampa, Fla. Although the shipment made the trip by sea without incident, the cigars were stolen from a truck during inland transport.
The Clinic team took the Altadis case because the dispute raised important questions of liability involving goods shipped by sea and land—which total more than a trillion dollars in U.S. trade each year.
"The legal issue is difficult and significant: Which federal legal regime provides the rules to determine a carrier's liability for damaged cargo that is carried by both ship and truck?" said Sturley, whose specialties include maritime law, commercial law and Supreme Court practice.
Sturley, who clerked at the Supreme Court for Justice Lewis F. Powell Jr. in the 1982-83 term, explained that the courts of appeals have been split on the answer to this question, with some courts applying the federal transportation law for land to determine a carrier's liability and others applying the federal law for ocean carriage. The lower courts' disagreement over the issue has made it ripe for review by the Supreme Court.
By deciding to represent Altadis, the Clinic enabled an important case to proceed. The case would have been abandoned because the amount of money at stake in the individual case was too small to justify the normal expense of Supreme Court litigation. The client obtained the benefit of first-rate legal representation at no charge and the Clinic obtained a perfect vehicle for the students to learn first-hand about Supreme Court practice, Sturley said.
For students in the Clinic, being a part of the Supreme Court legal team meant working on almost every facet of the case.
"We were finding case law on point, pouring over statutory history, and crafting policy arguments that would help our client," Keller said. "Students also produced the entire first draft of the certiorari petition," he said, noting it was then revised under the guidance of Sturley, Frederick and Brendan Crimmins, a 2003 Law graduate and an associate at Kellogg, Huber, Hansen, Todd, Evans & Figel in Washington, D.C. Both Crimmins and Frederick (who clerked for Supreme Court Justice Bryon R. White and is a partner at Kellogg, Huber where he regularly represents private clients in the Supreme Court) are Sturley's former students.
"At times I felt like Indiana Jones searching for a lost text when I was digging through statutory history from literally 100 years ago," said Keller, noting that in its brief to the Court the team needed to summarize a statute known as the Carmack Amendment, which the Clinic argued was the federal law that applied in the Altadis case.
"We had to go back through the legislative history and the changes to the Carmack Amendment to succinctly explain how the statute had become so convoluted that six separate statutory provisions really all stemmed from the same 1906 statute," Keller explained. "This required opening library books that I swear hadn't been opened in decades as they were dusty and old."
In the end, the countless hours of research paid off for the students when they learned in January that the Supreme Court had agreed to review their case.
"There's a purpose for doing all the work and that's because you're trying to win your case," said Sammy Ford, a third-year law student.
Once the Clinic persuaded the Court to hear the Altadis case, a settlement was reached between the parties in mid-February—before the case could be argued before the Supreme Court. Therefore, the Court did not issue an opinion, leaving the issue in the case unresolved. Sturley explained that the defendant in the case offered the Clinic's client a settlement that was more generous than the result that the client would have achieved if it had won the case before the Court.
"It would have been gratifying to participate with the students in clarifying the law in this important and complicated area," said Sturley, who has participated in several dozen Supreme Court cases. "But our real pedagogical goal is to train our students to be better lawyers which means, among other things, best serving their clients' interests. In this case, they learned that the best way to serve a client's interest is not necessarily to get a favorable opinion from the court."
Sturley added that at the time the settlement happened, the students had already done the overwhelming bulk of the work on writing a merits brief.
"So in effect, they've had the experience of writing a successful cert petition and writing a merits brief."
Despite the settlement, the students traveled to Washington, D.C., in late March to see an argument at the Supreme Court and meet with two Court officials—the chief deputy clerk and the administrative assistant to the Chief Justice.
"Seeing an oral argument for the first time, I was impressed by how the Justices worked through a problem, probing the strengths and weaknesses of each side's argument," third-year law student Benjamin Wallfisch, 29, said.
"An otherwise dry land-use dispute became a colorful and vigorous investigation of some thorny legal questions," he said, noting the impressive talent of the two experienced advocates he watched argue the case. "It gave me a greater appreciation of the skill required of a Supreme Court advocate. But it was priceless to hear the vivid stories of two Supreme Court veterans, who gave us an inside perspective on the operation of the Court."
The same students who worked on the Altadis case are in the preliminary research stages of a new case involving the Fourth Amendment, which governs search and seizure issues. Another four students who joined the Clinic in the spring semester filed the clinic's second petition for certiorari in March. That case, United States ex rel. Bly-Magee v. Premo, involves a whistleblower seeking relief under the False Claims Act. The Court is expected to rule on the petition in May.
While it's still fairly unusual for a law school clinic to take a case to the Supreme Court, the competition to work on this type of litigation has been growing recently. In the past year, Supreme Court clinics have also been introduced at such law schools as Yale, Virginia and Northwestern. Stanford University established the first Supreme Court clinic in 2003 and Harvard University announced it will start one next fall.
Frederick, who will argue his 21st case before the Supreme Court this week, said this type of clinic exposes students to the practice of law at the highest levels of the profession at the highest level of the judicial system.
"The students have also developed a wonderful rapport with one another working on these cases as a team," he said.
Students said they were surprised at the amount of teamwork and interaction required.
"Most people think of appellate lawyers as meticulous brief writers who are holed up in an office pouring over cases," Keller said. "That's not exactly false—it's just not the whole picture. We spent hours bouncing ideas and arguments off of each other."
Students, many of whom work as editors on law journals, were often pushed to produce a lot of high-quality work in a very short time.
"We prepared the cert petition in roughly three weeks," Ford said. "Because of the intensity of the work, and the confidentiality we had to maintain at the beginning, the clinic forged close bonds between the participants."
Third-year student Ashley McKeand said the Clinic's value has been to provide work that has practical meaning and significance.
"It's helped me get a sense of whether this type of work is something that I would like to do," she said. "It's also excellent practice to get practical writing experience."
Joe Conley, a graduate history student before attending law school, said knowing his work has the potential of being read by a Justice is motivation to be exhaustive in his reading of cases and disciplined in his writing.
"This is the kind of training you wouldn't get anywhere else," he said.
Second-year law student Aaron Liskin agreed, "This was an opportunity to get hands-on experience working on an actual case and learning how the process works."
The experience is also helping students prepare to clerk. After graduation this May, the six students from the Clinic's inaugural class will work as law clerks to U.S. federal judges with the exception of one student who will clerk for a justice on the South African Constitutional Court.
Part of the preparation for Supreme Court litigation is teaching students to figure out what cases the Court might want to hear, and how to properly frame and brief cases for the Court.
"So many clients are represented at the Supreme Court by lawyers who have no experience in Supreme Court practice," Sturley said. "Supreme Court advocacy is a very specialized skill. The fact that a lawyer is good at making a jury argument is not necessarily going to mean the lawyer is good at making a Supreme Court argument."
"They may be good lawyers but they are not aware of what the court is looking for, or which aspects of the client's case need to be presented to the court," he said. "So having the Clinic and working on these cases enables the students to learn what the Court is looking for and also enables the clients to have their cases presented in a way that stresses their strongest arguments."
Sturley added that he passes out statistics on the first day of class showing how hard it is to persuade the Court to review a case, not to intimidate students but to give them a sense of realism.
"The odds are against you," he will tell his students. But, he also teaches students how to improve those odds.
"We don't choose random cases. We choose cases that we think have a realistic shot," Sturley said. "So we have already gone into this with a better-than-average chance of success, and then our job becomes to turn that better-than-average chance into a successful petition."
BY Laura Castro
School of Law
PHOTOS at U.S. Supreme Court: Claire Duggan
ON THE BANNER: Capital Punishment Clinic students and faculty
standing in front of the
U.S. Supreme Court after oral arguments in three of their cases in January.
From left to right: Anna Baker, Jasmine Erdener, Eric Harrington, Linford Coates, Meghan Shapiro,
Jamie Dickson, Sian Crichton, Kimberly Gustafson, Professor Jordan Steiker, Stefanie Collins,
Professor Rob Owen,
Mary Beth Hickcox-Howard, Chase Hamilton, Professor Maurie Levin,
Paul Riffe, James Dowd, Daniel Gagarin, Christina Thoda and Professor Jim Marcus.
Office of Public Affairs
P.O. Box Z
Austin, Texas
Fax 512-471-5812


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Name that fish
Ok, I don't have a picture but this should still be easy.
I saw a fish at my LFS that looks just like the pictures I have seen here of a Zebra Danio but it was thinner, longer and had much longer fancier fins. I think it was a killfish but am not sure. The only other difference was an upturned mouth and this is why I want to know because I want a fish that will eat fruit flies off the surface and other critters.
Long finned zebra danio?
Can't help with the ID i'm afraid, still being a newbie and all, but if you want fish that eat critters off the surface the Golden pachax are your friends. I assume it's work with all panchax but as i only have Golden ones (which are a really lovely colour by the way) i can only comment on them.
The other say i was watching my tank in a thoughtful moment and i saw a spider (about 1.5cm across inc. legs) drop onto the water. I have no idea how it got in there, but it did. The panchax all swarmed up to it and it was gone within seconds, before i even had time to get out of my chair to fish it out. I watched them carefully for a couple of days to see if it had done them any harm, but they seemed fine, and certainly relishd the extra snack!
Why do you want fish that eat flies? You got youself a biblical plague going on there?
If this fish does look like a killifish, I'd look into the Aphyosemion and Epiplatys genera. Killifish do snap on insects. What color are these fish, Chris?
They were the exact same color as the Zebra Danios just much thinner, a little longer and the fins were very fancy.
As for why, just because I want to feed them different types of food and so my kids can feed them and see them eat the food off the surface. Really just as a new thing so I can watch them eat and my kids can have some fun with them.
Fair enough, it was facinating to watch them take apart the spider!
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CERN Courier
Oct 6, 2003
Faces and Places (page 2)
Royal Society elections recognize research in particles and waves
Research in particle physics and gravitational waves has been recognized in the 2003 elections to the Royal Society. Valentine Telegdi, who is professor of physics at the Eidgenössiche Technische Hochshule, Zurich, has been elected as a foreign member. The Royal Society's citation observes that Telegdi has measured every property of the muon, namely: parity violation in the π → μ → e decay chain; the muon mass; the positron spectrum from polarized µ-decay; µ-capture rates; the muon-neutrino helicity; and the RF spectroscopy of muonium, and all were done with great simplicity and elegance. His study, with a group from Argonne, of the asymmetries in polarized neutron decay is described as perhaps "his most informative work yet, directly yielding the structure of the ß-decay coupling".
Peter Dornan, head of high-energy physics research at Imperial College, London, and James Hough, director of the Institute for Gravitational Wave Research at the University of Glasgow, have both been elected members of the Royal Society. Dornan is recognized for his role in suggesting the possibility of searching for charm decays using the SLAC rapid cycling bubble chamber and initiating an imaginative scheme to provide the necessary trigger. He later led the Imperial College group into the ALEPH collaboration at CERN, developing the experiment's very precise inner tracking chamber in order to study heavy flavour physics. Hough, for his part, has brought the UK to the forefront of research in the detection of gravitational waves, with the development of innovative and practical laboratory techniques. Aspects of these techniques have been successfully transferred to other fields and to industry.
Turbulence pioneers Kraichnan and Zakharov awarded 2003 Dirac Medal
Robert H Kraichnan and Vladimir E Zakharov, two pioneer physicists in the field of turbulence, have been awarded the 2003 Dirac Medal of the Abdus Salam International Centre for Theoretical Physics.
Robert Kraichnan, who was one of Albert Einstein's last assistants at the Institute for Advanced Study in Princeton, has had a long career as a consultant in a variety of governmental organizations and private firms, including MIT, the National Science Foundation and the US Department of Energy. He has conducted pioneering research on field-theoretic approaches to turbulence and other non-equilibrium systems. Most noteworthy are his insights into the inverse cascade for two-dimensional turbulence.
Vladimir Zakharov, who is director and professor of physics at the Landau Institute for Theoretical Physics in Moscow, is an expert in the mathematical physics of nonlinear phenomena. Zakharov's work has proven to be instrumental to our basic understanding of plasma physics, hydrodynamics, magnetism and optics, in particular contributing to a deep understanding of weak wave turbulence.
Prague honours theory and experiment
Frank Wilczek of the Massachusetts Institute of Technology and Guenakh Mitselmakher of the University of Florida have been awarded commemorative medals from the Faculty of Mathematics and Physics of the Charles University in Prague. Wilczek received his medal as "one of the world's most outstanding theoretical physicists", for work including the discovery of "asymptotic freedom" and other results of fundamental importance.
The award for Mitselmakher acknowledges his achievements as one of the "world's leading experimental particle physicists". The citation mentions his contributions to experiments at particle colliders as well as his integrating role in international research, including contributions to co-operation between the Charles University and major research centres.
- Page 1: Faces and Places
- Page 2: Faces and Places (page 2)
- Page 3: Faces and Places (page 3)
- Page 4: Faces and Places (page 4)
- Page 5: Faces and Places (page 5)


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Version: 9.3.7.v20160115
private support for your internal/customer projects ... custom extensions and distributions ... versioned snapshots for indefinite support ... scalability guidance for your apps and Ajax/Comet projects ... development services from 1 day to full product delivery
Table of Contents
This chapter discusses various options for configuring logging.
Jetty provides logging via its own
org.eclipse.jetty.util.log.Logger layer, and does not natively
use any existing Java logging framework. All logging events, produced via
the Jetty logging layer, have a name, a level, and a message. The name is a
FQCN (fully qualified class name) similar to how all existing Java logging
frameworks operate.
Jetty logging, however, has a slightly different set of levels that it uses internally:
For events serious enough to inform and log, but not fatal.
Informational events.
Debugging events (very noisy).
Exception events that you can safely ignore, but useful for some people. You might see this level as DEBUG under some Java logging framework configurations, where it retains the ignore phrase somewhere in the logging.
Jetty logging produces no FATAL or SEVERE events.
Configure the Jetty logging layer via the
org.eclipse.jetty.util.log.Log class, following these
Load Properties
First from a Classpath Resource called
jetty-logging.properties (if found).
Then from the
Determine the log implementation.
If property
org.eclipse.jetty.util.log.class is defined,
load the class it defines as the logger implementation from the
server classpath.
If the class
org.slf4j.Logger exists in server
classpath, the Jetty implementation becomes
If no logger implementation is specified, default to
You can create your own custom logging by providing an implementation of the Jetty Logger API. For an example of a custom logger, see JavaUtilLog.java.
By default, the internal Jetty Logging discovery mechanism will load
logging specific properties from a classpath resource called
jetty-logging.properties and then initialize the
Logging from a combination of properties found in that file, along with
any System Properties.
A typical jetty-logging.properties file will include at least the
declaration of which logging implementation you want to use by defining a
value for the
Examples for various logging frameworks can be found later in this documentation.
Default Logging with Jetty's StdErrLog
Using Log4j via Slf4jLog
Using Logback via Slf4jLog
Using java.util.logging via Slf4jLog
Using java.util.logging via Jetty's JavaUtilLog
Capturing Multiple Logging Frameworks via Slf4jLog


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Turn the Page
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Read our first book "Shave Your Balls & 100 Other Things Your Mother Should Have Told You."
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text:
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Latin American applied research
versión impresa ISSN 0327-0793
Lat. Am. appl. res. v.34 n.4 Bahía Blanca oct./dic. 2004
Cosserat continua-based micro plane modelling. Theory and numerical analysis
G. Etse1 and M. Nieto2
1 CONICET and Center for Numerical and Computational Methods in Engng., University of Tucumán, Roca 1800, 4000-Tucumán, ARGENTINA. email@example.com
2 Civil Engng. Department, University of Santiago del Estero, 4200 - Sgo. del Estero, ARGENTINA
Abstract — The well-known micro plane theory is extended to account for micro rotations and couple stresses in the framework of the micro polar Cosserat continua. The main purpose is to obtain reliable macroscopic constitutive equations and models for engineering materials like concrete and other composites based on available and precise information of their complex microstructure. The proposed macroscopic descriptions account also for anisotropic material response behavior by means of the well-developed micro plane concept applied within a micro polar continuum setting. For the formulation of the micro polar-based micro plane theory a thermodynamically consistent approach is considered, whereby the main assumption is the integral relation between the macroscopic and the microscopic free energy as advocated by Carol et al. (2001) and Kuhl et al. (2001). Thereby, the micro plane laws are chosen such that the macroscopic Clausius-Duhem inequality is fully satisfied. This theoretical framework is considered to derive both elastic and elastoplastic micro polar micro plane models. Numerical predictions of the uniaxial tensile and simple shear tests in plane strain conditions obtained with a micro polar micro plane elastoplastic model are also presented and contrasted to the corresponding predictions of the classical micro polar elastoplastic model.
Keywords — Plasticity. Micropolar. Micro-Plane. Localized Failure.
One of the most successful constitutive theories for the analysis of the engineering materials is the micro plane theory which is characterized by three relevant features. On one hand, it incorporates microscopic information in the macroscopic material formulation in a natural way. On the other hand, very simple constitutive equations at the micro plane level lead to highly accurate macroscopic predictions of material behaviors. The third relevant aspect of the micro plane theory is its capacity to model anisotropic material behaviors. Actually, this was one of the most important objectives of the original proposal by Taylor (1938) which is based on the definition of fully independent uniaxial stress-strain relations on several planes of the material.
Based on Taylor's idea the micro plane theory was then pioneered by Bazant and Gambarova (1984), Bazant (1984) and Bazant and Oh (1985, 1986).
For the formulation of the uniaxial stress-strain relations on the micro planes, two different approaches may be considered, whereby the static or the kinematic constraint require that either the stresses or the strains on each micro plane are the resolved components of their macroscopic counterparts. The static constraint was extensively used until the first application of the micro plane theory to continuum damage mechanics and to cohesive-frictional materials by Bazant and Gambarova (1984) and Bazant (1984). It was in those works were the name micro plane appeared for the first time instead of the original terminology slip theory which was related to the plastic behavior assumption on slip planes by Taylor and other authors like Batdorf and Budianski (1949). The potentials of the micro plane theory for describing non linear response behaviors of engineering cohesive-frictional materials like concrete were extensively demonstrated in the first contributions by Bazant and coauthors related with the micro plane theory and, more recently, in the works by Bazant and Prat (1988), Carol et al. (1991, 1992) and Carol and Bazant (1997), among many others.
Recently, the lack of a thermodynamically consistent approach for deriving micro planebased constitutive formulations was advocated by Carol et al. (2001) who demonstrated that the satisfaction of the second law of thermodynamics could generally not be guaranteed. To solve this fundamental shortcoming they proposed a method for deriving micro plane constitutive formulations within a thermodynamically consistent framework by means of the incorporation of a microscopic free Helmholtz energy on every micro plane. This concept was successfully extended for inelastic material behavior such as damage and plasticity by Kuhl et al. (2001). However, both this work as well as the previous one by Carol et al. (2001) were concerned with classical Boltzmann continua (elastic and inelastic).
Despite the advantages of the micro plane theory and the considerable progress of the related models since the original Taylor's proposal, it still has open questions and the most relevant one is how to incorporate more detailed microscopic information in the global constitutive equations to be able to reproduce particular material behaviors.
In this work the thermodynamically consistent approach to derive micro plane models is further extended for micro polar continua in the spirit of Cosserat and Cosserat (1909). The main aim is to enrich the microscopic kinematic and strength features of the micro plane formulation so as to reproduce particular and more complex behaviors of the internal structure of composite quasi-brittle materials like concrete whereby the presence of aggregates may contribute to the development of microrotations in characteristic planes during load histories beyond the elastic limit.
The second motivation of the micro polar micro plane theory in this work is related to the regularization of the post peak predictions of the smeared crack concept. In this sense, the incorporation of the micro polar length scale at the microscopic level leads to an intrinsically non local micro plane constitutive relation when the additional degrees of freedom of micro polar continua are activated. This characteristic length accounts for mesh objectivity during FE simulations of softening behaviors.
After revising the most relevant equations of the Cosserat continuum in the next section, the micro plane theory is extended to the micro polar continuum in section 3. Thereby, both the static and the kinematic constraint are redefined to include the macroscopic couple stress and the macroscopic curvature projections at micro planes, respectively. Section 4 is concerned with the hemispherical integrations which are required for the closed form formulation of some micro polar micro plane models. In section 5 the attention focuses on the method for deriving micro polar micro plane constitutive equations. Section 6 refers to the application of the proposed thermodynamically consistent method to the formulation of general 3D linear elastic models. In section 7, elastoplastic constitutive equations are derived both for the general case and for the von Mises type model. Finally, in section 8 the numerical predictions of the micro polar micro plane elastoplastic von Mises model for the uniaxial tensile and simple shear tests are presented and compared with those of the classical micro polar elastoplastic von Mises model. The comparative results illustrate the fundamental differences between the predictions of the micro polar micro plane and the classical micro polar models. Moreover, the results also demonstrate the potentials of the proposed thermodynamically consistent approach to derive constitutive models based on enriched kinematic and strength properties at the microscopic level and thus allowing for computational simulations of complex anisotropic response behavior of engineering materials.
In this section the relevant equations of the micro polar Cosserat theory are presented. This theory was proposed by Cosserat and Cosserat(1909) at the beginning of the twenty century. However, it was only in the last decades that a revival of this theory took place through the contributions of many different authors who analyzed the benefits of the micro polar theory from different points of view. Among others, the most prominent work in this regard was made by Erin-gen (1968) who presented a detailed analysis of elastic micro polar continua and of their mechanical features. The first application of the micro polar continuum in non-linear computational solid mechanics took place at the end of the 1980's in the works by Mühlhaus (1989) and de Borst (1991) who analyzed the potentials of the elastoplastic micro polar constitutive theory to regularize the predictions of post-peak response behaviors of structural systems within the theoretical framework of the smeared-crack approach. In the same line, Steinmann and Willam (1991), Willam and Dietsche (1992), Sluys (1992) and Willam et al. (1995) analyzed the localization indicators and localization properties of nonlinear micro polar continua.
A. Stresses at Macro Level
The stress components in micro polar continua defined in the general 3D domain Bfollow from the quasi-static form of linear and angular momentum which reads (omitting body forces and body couples for simplicity)
|divst = 0
|divmt + e : s = 0
whereby m is a non symmetric second order tensor which represents the couple stresses of the micro polar continuum. The local equilibrium equations of the classical continuum and the corresponding typical symmetric form of the stress tensor s are restored when divmt = 0 ® e : s = 0. Here e denotes the third order permutation tensor.
B. Strain and Curvature at Macro Level
The deformation of the micro polar continuum is a consequence of the simultaneous action of two types of local or micro motions: the classical or translatory ones, represented by the displacement field u, and the pointwise rotations characterized by the first order tensor w. This enriched motion field leads to the following strain measures
= Ñxu - w (2)
k = Ñxw
with w = -e × w. Here represents the non-symmetric micro polar strain tensor and k is the micro curvature tensor which takes into account the differential changes of the micro rotations in the neighborhood of a point.
The second order strain tensor may finally be decomposed into a symmetric and skew-symmetric contribution = sym + skw with
In the micro plane theory the macro-mechanical response behavior of materials is controlled by constitutive equations of characteristic planes or micro planes by means of the static or the kinematic constraint, requiring that either the stresses or the strains on each micro plane, respectively, can be derived by projections of their macroscopic counterparts.
Figure 1: Micro plane normal and tangent components of the strain and curvature tensors
A. Stresses and Couple Stresses at Micro Planes
For the case of the static constraint the stress and couple stress (traction) vectors on each micro plane, see Fig. 1, are given by pre-multiplication with the micro plane normal vector n, i.e.
The micro plane stresses and couple stresses follow as their normal and tangential components
and are obtained as projections of their macroscopic counterparts to the micro planes
Here, the second and third order projection tensors N and T are defined with [ | ]ijkl = dikdjl the fourth order identity tensor and n the micro plane normal vector as
|N = n n
|T = n × | -n n n
Thus, and represent the normal projected stress and normal projected couple stress, respectively, while and denote the tangential projected stress and tangential projected couple stress vectors. Note however that these projected components of the macroscopic stress and couple stress tensors are in general different from those derived from constitutive equations at the micro planes, that we shall denote as sN, sT, mN, mT in the sequel.
The micro plane normal and tangential stresses and couple stresses may be further decomposed into symmetric and skew-symmetric parts according to the usual decomposition strategy in a micro polar continuum. Nevertheless, since we shall not use explicitly the static constraint in the sequel, we refrain from doing so.
B. Strains and Curvatures at Micro Planes
For the case of the kinematic constraint the strain and curvature vectors on each micro plane, compare Fig. 1, are given by post-multiplication with the micro plane normal vector n, i.e.
t = × n = Ñnu - w ´ n; tk = k × n = Ñnw (8)
The micro plane strains and curvatures follow as their normal and tangential components
|N = Nn
|kT = tk - kN
|kN = kNn
|T = t - N
These equations are valid both for the symmetric as well as for the skew-symmetric parts of the strain and curvature measures. Taking into account the following properties
|skw × n = -n × skw, kskw × n = -n × kskw
|sym × n = n × sym, ksym × n = n × ksym
the symmetric and skew-symmetric micro plane strain components in the normal and tangential directions of micro planes are then defined by
|N = N : sym = N :
|Tsym = T : sym = Tsym :
|Tskw = -T : skw = -Tskw :
while the corresponding micro plane curvature components in the normal and tangential directions of micro planes are given by
|k = N : ksym = N : k
|kTsym = T : ksym = Tsym : k
|kTskw = -T : kskw = -Tskw : k
Here, in addition to the projection tensor T the symmetric and skew-symmetric projection tensors T symand T skw with T = T sym + T skw are defined as
|Tsym = n × | sym - n n n
|Tskw = n × | skw
whereby [ | sym]ijkl = [dikdjl + dildjk ] / 2 and [ | skw ]ijkl = [dikdjl - dildjk ] / 2 are the symmetric and skew-symmetric parts of the fourth order identity tensor | = | sym + | skw .
The integration properties of the micro plane normal vector n are documented e.g. in the works of by Bazant and Oh (1986) and Lubarda and Krajcinovic (1993) are applied to perform analytical integrations over the hemisphere w
with [I]ij = dij the second order identity tensor and the volumetric and symmetric deviatoric fourth order projection tensors defined as
For later use the relevant products of the projection tensors T and N are given as
|[ TT × T ] ijkl : = TaijTakl = ninkdjl - ninjnknl
|[ N N ] ijkl = ninjnknl
and thus integrate over the hemisphere into
Accordingly, the relevant products of T sym and T skw are given as
and thus integrate over the hemisphere into
Based on the proposal by Carol et al. (2001) and Kuhl et al. (2001) we develop here a general formulation for thermodynamically consistent micro polar micro plane constitutive laws. The macroscopic Clausius-Duhem inequality for isothermal processes reads
Next, the main assumption is given by a relation between the microscopic and macroscopic free energy, compare Carol et al. (2001) and Kuhl et al. (2001)
Moreover we consider the convenient uncoupled format of the microscopic free energy dependent on strain and curvatures components N, Tsym, Tskw and kN, kTsym, kTskw, respectively, as well as on the sets of internal variables qu, qw, related with the translatory motions and rotations, respectively
Thus an additive decomposition of the total microscopic free energy into a membrane energy and a bending energy was assumed. This corresponds to the particular case of micro polar response behavior where the membrane-bending coupling diminishes to zero.
The evolution law of the microscopic free energy follows from the kinematic constraint relations in Eqs.(11) to (13)
with sN, sTsym and sTskw the microscopic constitutive stresses
and mN, mTsym and mTskw the microscopic constitutive couple stresses
and , the microscopic dissipation rate of membrane and bending type, respectively,
whereby indicates the appropriate contraction. Recall however, that the constitutive stresses and couple stresses on the micro planes are in general different from the projected micro plane stress and couple stress components , , and , , obtained by means of the static constraint.
Due to the membrane-bending decoupling assumption, the stress tensor components can be derived from that portion of the total microscopic energy which is only related with the translatory motion while the components of the couple stress tensor follow from the other portion of the total microscopic energy, related with micro rotations .
The evolution of the macroscopic free energy can then be obtained applying the integral Eq.(21) to the evolution law of the microscopic free energy Eq.(23) as
The macroscopic stress tensor and couple stress tensor are thus obtained from the microscopic constitutive stress and couple stress components as follows
In order to satisfy the macroscopic dissipation inequality
we will require that the total microscopic energy dissipation on every micro plane is nonnegative
which is a stronger requirement than that of Eq.(29) and therefore represents a sufficient condition to fulfill the second law of thermodynamics.
The evolution law of the microscopic free energy in Eq.(23) can be understood as the microscopic form of the Clausius-Duhem inequality for the isothermal case, which can be now rewritten as
with the microscopic stress and couple stress power
In case of hiper-elasticity the free energy agrees with the stored energy which is assumed here to be composed by uncoupled membrane and bending contributions in the form
whereby for linear elasticity the elastic moduli , , , , and were introduced into the microscopic energy functions as
Hyper-elastic behavior of both the membrane and bending stiffness components is characterized by zero internal variables (qu = qw º 0). Therefore, the microscopic free energy reduces to
The previous definition of the microscopic Clausius-Duhem inequality in Eq.(31) then leads to the microscopic constitutive stresses and couple stresses as thermodynamically conjugate variables to the strain and micro curvature components, respectively
From the macroscopic version of the Clausius-Duhem inequality the macroscopic stress and couple stress tensors follow as functions of the microscopic components
The last equation can alternatively be rewritten as
whereby the macroscopic membrane and bending constitutive moduli are defined as follows
with the subscript i = u, w.
Next, under the common assumption of micro plane isotropy the tangential strain and curvature vectors and the tangential stress and couple stress vectors remain parallel during the entire load history. Consequently, we consider the following simplification
Assuming further that the constitutive moduli are independent from the orientation of the micro planes we arrive at
The integration formulae (14) to (20) allow an analytical evaluation of the integrals in Eq.(41) to render
The comparison of Eq. (41) with the general isotropic non symmetric elastic tensors for decoupled membrane-bending behavior
then leads finally to the identifications
whereby a1 := L and a2 + a3 := 2G are recognized as the common Lamé parameters, while a2 - a3 := 2Gc is the micro polar shear modulus which couples the skew-symmetric stress-strain components.
In this section the thermodynamically consistent formulation of the micro plane-based micro polar elastoplastic model is presented both for the general case and for the von Mises type model.
A. General Case
The elastoplastic type of micro polar continuum response behavior is characterized by the additive decomposition of the macroscopic total strain and curvature tensors into elastic and plastic contributions
= e + p (44)
k = ke + kp
The kinematic constraint assumption extends the applicability of the additive decomposition to the microscopic level. As a consequence, the total strain and curvature components at micro planes can be expressed as
In the most general case the tensor of internal variables includes the plastic contributions of all the strain and curvature components at the micro planes
whereby the scalar internal variable xmic accounts for the simplest isotropic hardening/softening response.
The microscopic free energy follows from the definition of the elastic free energy and of the microscopic free energy functions in equations (35), (34) and (34) as
whereby the restricted form of isotropic hardening/softening behavior is taken into account by means of the term .
The constitutive stresses and couple stresses at micro planes are then obtained from the evaluation of the microscopic Clausius-Duhem inequality
The evolution of the internal variables is restricted by the inequality of the microscopic dissipation
Thus, the yield function on each micro plane can be defined in the form
whereby the function of the microscopic constitutive stresses and couple stresses is characterized by the gradients
For the associated case the plastic strain and curvature evolution laws are obtained from the variational problem defined by the dissipation inequality (49) under consideration of the convexity condition and of the constraint (50). For the general non-associated case we postulate instead
with the flow directions at each micro plane
in terms of the plastic multiplier and of the gradients to the microscopic plastic potentials .
The Kuhn-Tucker loading-unloading conditions as well as the consistency condition can be defined on each micro plane as
An explicit solution for the plastic multiplier can be obtained from the consistency condition
Finally, the macroscopic elastoplastic constitutive equations can be expressed as
with the elastoplastic operators
whereby the modified gradients are defined as
with the subscript i = u, w.
Remark: the resulting format of the micro polar micro plane elastoplastic tangent operator is quite similar to that of the classical micro polar model (compare Willam et al. (1995)) with exception of the integrals which account for the microscopic contribution to the macroscopic operator in case of the micro polar micro plane formulation.
B. Von Mises Type Model
The classical micro polar elastoplastic von Mises type model, see e.g. de Borst (1991), is characterized by the yield condition
with s the deviator of s and with yield stress with linear hardening
Figure 2: Boundary conditions. Plane strain axial extension and simple shear tests.
Here the evolution of the hardening-softening parameter is given by
Assuming that the second invariant of the stress deviator tensor s is a function of the tangential stress vectors and of the tangential couple stress vectors of the micro planes, the von Mises yield condition at the micro plane level can be expressed in the format
with the yield stress with linear hardening
Here the evolution of the hardening-softening parameter is given by
which, similarly to the macroscopic description, coincides with the plastic multiplier.
In this section we analyze the predictions of the micro polar micro plane elastoplastic von Mises model for the uniaxial tensile and simple shear tests. Fig. 2 illustrates the boundary conditions of these tests which were analyzed under plane strain constraints. In both one element meshes of Fig. 2 the standard bilinear quadrilateral finite element with four integraion points was used. This finite element formulation of micro polar continuum problems is obtained by means of discretizations of the weak form of the balance equations in the spirit of the Dirichlet variational principle, see Willam et al. (1995). Thereby the displacements and rotations (and their variations) are approximated by the same shape functions according to the Galerkin-Bubnov method.
In the simple shear test, full displacement and rotation restraint were considered on the nodes located on the bottom of the quadrilateral element while only the vertical displacements were restrained on the other element nodes. On the other hand, in case of the axial extension test, the full displacement and rotation restraint were assumed only in one element node as indicated in Fig. 2 while in other two nodes one displacement possibility together with the in plane rotation were restrained according to the double symmetry of the problem. Both, the yield condition and hardening/softening evolution law are those indicated in section VII.B. The micro polar elastic parameters at micro planes for the numerical analysis were obtained according to the equations in section 6 so that the overall Young's modulus is E = 30000 N/mm2, the Poisson's ratio n = 0.2, the micro polar shear modulus Gc = G and the characteristic length lc =1mm. Following the equations (43) we obtain: = 33333.33, G = 12500, = 19444.45, = 25000, = = = 25000.
The non-symmetric stress field in the case of a micro polar continuum and the resulting complex form of the second invariant J2 avoids an analytical procedure to obtain the relationship between the microscopic and macroscopic von Mises stresses 0mic and 0mac , respectively. As a consequence and for the purpose of the numerical analyses in this work, these stresses were chosen so that similar predictions of the J2 type maximum strength corresponding to both the uniaxial tensile and simple shear tests are obtained with the microscopic and the macroscopic micro polar models. From this numerical calibration the
Figure 3: Prediction of the axial extension test.
Figure 4: Plastic process evolution in micro planes. Axial extension test
responding to both the uniaxial tensile and simple shear tests are obtained with the microscopic and the macroscopic micro polar models. From this numerical calibration the resulting values are 0mic = 23.5 N / mm2 and 0mac = 50.0 N / mm2 for the axial extension test while these stresses are 0mic = 29.0 N / mm2 and 0mac = 50.0 N / mm2 for the simple shear test.
A. Axial Extension Test
Fig. 3 illustrates the numerical predictions of the uniaxial tensile test with the micro polar micro plane elastoplastic model and with the classical micro polar elastoplastic model. Three different types of evolution laws of the stress functions mic and mac were considered for these models, corresponding to perfect plasticity, linear hardening and linear soft-
Figure 5: Stress-strain prediction of the axial extension test.
ening behavior. The first observation from the comparison between the predictions of both types of micro polar models is that their response behaviors during the elastic range agree very well. Also the overall predictions of both models in the plastic range under linear softening and perfect plasticity are very similar. However, under linear hardening assumption the classical micro plane model leads to a much more ductile response behavior indicating that this formulation is more sensitive to variations of the hardening evolution law.
The microscopic model allows a much more detailed analysis of the failure mechanism and evolution as can be observed in Fig. 4 which shows the spatial development of the plastic process in the case of the axial extension test predicted by the micro polar micro plane model with linear hardening. Each diagram in this figure corresponds to the load step indicated in the load-displacement curve (compare Fig. 3). During the load history, a tendency towards texture evolution can be recognized. Under uniaxial tension, the plastic behavior develops in the planes located under an angle of about 45o towards the loading axis in the loading plane. Similar effects were
Figure 6: Prediction of the simple shear test.
observed by Kuhl et al. (2001) in the uniaxial tensile test's predictions obtained with the micro plane elastoplastic model for the classical Boltzmann continuum. We analyze now the fundamental differences between the numerical predictions of the micro polar micro plane and of the classical micro polar model with perfect plasticity in Fig. 3. In the case of the classical micro polar model with perfect plasticity the requirement for constant values of J2 due to the yield condition
is responsible for the plateau in the J2 evolution which immediately follows the elastic response, as indicated in Fig. 5. On the other hand, the evolution of the the axial tensile force as well as that of the vertical tensile stress in Fig. 3 and Fig. 5, respectively, show a smooth transition from the elastic to the perfect plastic regime.
The micro polar micro plane model with perfect plasticity leads to a macroscopic stress tensor's evolution during the axial extension test characterized by an initial smooth softening response of J2 and subsequent plateau.
Figure 7: Plastic process evolution in micro planes. Simple shear test.
The same response behavior is observed in the evolutions of the vertical tensile stress in Fig. 5 and of the axial force in Fig. 3.
B. Simple Shear Test
The numerical predictions of the micro polar micro plane model for the simple shear test and the comparison with the corresponding predictions of the classical micro polar model are indicated in Fig. 6. Both a linear hardening and a perfect plastic evolution laws were assumed for mic and mac in equations (64) and (67), corresponding to the micro plane model and to the macroscopic model, respectively. It is important to note that in the simple shear test, contrarily to the axial extension test, the microrotations are activated.
Fig. 7 illustrates the development of failure predicted by the micro polar micro plane model with linear hardening. Again, a tendency towards texture evolution can be recognized. However, in the case of the simple shear test, the inelastic deformation process takes place in the upper, lower, left and right micro plane. This strong failure distribution in micro planes explains the more ductile behavior of the simple shear test predicted by the micro plane micro polar model when compared to the corresponding predictions of the uniaxial tensile test. The results in Fig. 6 also indicate that the micro polar micro plane model with perfect plasticity leads, as expected, to a plateau of the external shear force. However, this is not the case of the classical Cosserat model which leads to continuous hardening of the external shear force although perfect plasticity was considered. This is due to the evolution of the nonuniform microrotations which are activated in this test.
In this work the thermodynamically consistent approach for deriving micro plane constitutive formulations by Carol et al. (2001) and Kuhl et al. (2001) was reformulated for elastic and inelastic micro polar continua. As in the previous work, the main assumption is the incorporation of a microscopic free Helmholtz energy on every micro plane, which in the present case includes the contributions of the additional degree of freedom and stiffness of the micro polar continuum, represented by the micro rotations and the couple stresses. Moreover, an uncoupled format of the free energy in terms of the membrane and bending contributions is considered.
From the resulting constitutive equations for the micro polar micro plane elastic model an explicit solution for the characteristic length was obtained in terms of the ratio between the bending elastic moduli and the micro polar shear modulus. The solutions for the micro polar micro plane elastoplastic model include the macroscopic explicit formulation of the constitutive tangential moduli in terms of the microscopic contributions. The general elastoplastic formulation for the micro polar micro plane model was particularized for von Mises type elastoplasticity.
The numerical results in this work show the predictions of the J2 elastoplastic model for the uniaxial tensile and simple shear tests. Also the main differences with the corresponding predictions of the classical micro polar elastoplastic model were highlighted.
The proposed constitutive theory allows the formulation of models based on relevant aspects of the material microstructure which exceeds the capacity of the theoretical framework developed so far for the prediction of anisotropic response behaviors.
1. Batdorf,S., B.Budiansky. "A mathematical theory of plasticity based on the concept of slip." Tech.Note 1871.N.A.C.A.. 1949. [ Links ]
2. Bazant,Z."Imbricate Continuum and its Variational Derivation". J.E.Mech., 110, pp.1693-1712. 1984. [ Links ]
3. Bazant, Z.P., P.G. Gambarova. "Crack shear in concrete: Crack band micro plane model." J. Struct. Eng., ASCE, 110, pp.2015-2036. 1984. [ Links ]
4. Bazant,Z.,B.Oh."Micro plane model for progressive fracture of concrete and rock." J.E.Mech., 111, pp.559-582. 1985. [ Links ]
5. Bazant,Z.,B.Oh. "Eficient numerical integration on the surface of a sphere." ZAMM, 66(1), pp.37-49. 1986. [ Links ]
6. Bazant,Z.,P.Prat. "Micro plane model for brittle plastic material: Part I & II." J.E.Mech., 114, pp.1672-1702. 1988. [ Links ]
7. Carol,I.,Z.Bazant,P.Prat. "Geometric damage tensor based on micro plane model." J.E.Mech., 117, pp.2429-2448. 1991. [ Links ]
8. Carol,I., Z.Bazant,P.Prat. "New explicit micro plane model for concrete: Theoretical aspects and numerical implementation." I.J.S.& Struc., 29, pp.1173-1191. 1992. [ Links ]
9. Carol,I.,Z.Bazant. "Damage and plasticity in micro plane theory." I.J.S.& Struc., 34, pp.3807-3835. 1997. [ Links ]
10. Carol,I.,M.Jirasek,Z.Bazant. "A thermodynamically consistent approach to micro plane theory. Part I." Int.J.S. & Struc., 38, pp.2921-2931. 2001. [ Links ]
11. Cosserat,E.,F.Cosserat. "Theory des corps deformables." Herman et fils, Paris.1909. [ Links ]
12. de Borst,R. "Simulation of strain localization: A reappraisal of the Cosserat Continuum." Eng.Comp., 8, pp.317-332. 1991. [ Links ]
13. Eringen,A. "Theory of micro polar Elasticity." Fracture, an Adv.Treatise.Ed.L.Liebowitz, Ac.Press.1968. [ Links ]
14. Kuhl,E.,P.Steinmann,I.Carol. "A thermodynamically consistent approach to micro plane theory. Part II." Int.J.S.& Struc., 38, pp.2933-2952. 2001. [ Links ]
15. Lubarda,V.,D.Krajcinovic. "Damage tensors and the crack density distribution." Int.J.S. & Struc., 30, pp.2859-2877. 1993. [ Links ]
16. Mühlhaus,H. "Application of Cosserat theory in numerical solutions of limit load problems." Ing.Archive, 59, pp. 124-137. 1989. [ Links ]
17. Sluys,P. Wave propagation, localization and dispersion in softening solids. Dissertation, Delft Univ.of Tech., Delft.1992. [ Links ]
18. Steinmann,P.,K. Willam. "Localization within the framework of micro polar elastoplasticity." 60th Anniv.Vol.Prof. Lippmann, V.Mannl, O.Brueller, J.Najar (eds.), Springer Verlag, pp.296-313. 1991. [ Links ]
19. Taylor,G. "Plastic strain in metals." J. Inst. Metals, 62, pp.307-324. 1938. [ Links ]
20. Willam,K.,A.Dietsche. "Regularization of localized failure computations." COMPLAS III. Edt. E.Onate, E.Hinton, R.Owen, Pineridge Press, pp.2185-2204. 1992. [ Links ]
21. Willam, K., A. Dietsche, M. Iordache, P. Steinmann. "Localization in Micro polar Continua." Cont.Models for Materials with Microstructure. Ed. H. Mühlhaus. J.Wiley & Sons Ltd., pp. 297-339. 1995. [ Links ]


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Trails TeamIn partnership with the Stanislaus National Forest, Tuolumne River Trust is helping to maintain our Sierra Nevada trails before and after the busy hiking season. It's a great opportunity to get out into nature and contribute to not only helping hikers, but also to keeping our watershed pristine. For upcoming opportunities, email firstname.lastname@example.com.
Dos Rios RestorationIn partnership with River Partners, Tuolumne River Trust is working to restore 1,600 acres of riverfront property where the Tuolumne and San Joaquin Rivers meet just outside of Modesto. Volunteer opportunities range from everything to removing invasive species, planting native plants, to installing bird boxes and developing hiking trails. For upcoming opportunities, email firstname.lastname@example.com.
Friendraising For the FutureShare your passion for the River by helping us reach out to others to keep our programs thriving. A few times a year our fundraising and advancement department can use your help to assemble and mail membership communications and/or phone our members to let them know about TRT happenings. Opportunities exist in San Francisco, Modesto, and Sonora. To get involved, please contact Rebecca Stievater at email@example.com.
Administrative Office Help - San FranciscoOur administrative office in San Francisco is currently looking for volunteers to help with office related activities. If you're interested in helping out in this way please contact out administrative office at (415) 882-7252.
Lead Hikes in the Upper Watershed. We are looking to expand our outings program and need volunteers to help locate, scout and lead hikes. Contact Patrick Koepele at email@example.com (209) 588-8636.
Organize a canoe trip on the River through Tuolumne River Trust for your friends and family. Contact Patrick Koepele at firstname.lastname@example.com or (209) 588-8636 for more information.
Write your city and state political figures thanking them for the steps they're taking to help protect the Tuolumne River and asking them to focus their efforts on water conservation and recycling. Visit the program page of the area you live (Bay Area, Central Valley, Sierra Nevada) for links and more information.
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My goal is to put up weight like this with 2 knee surgeries, no wraps, no belts, no steroids, no anything. Gonna be very hard, and probably won't happen, but I'm gonna try to make it happen.
My Training Log
My YouTube page
Training by Tone Barbaccio
New Dimensions Wellness & Education
Best geared meet @ 242
1030SQ, 640BP, 685DL and 2355 total
Best raw meet w/sleeves @ 242
705SQ, 457BP, 749DL and 1912 total
Best raw meet w/sleeves @ 275
700SQ, 452BP, 722DL and 1874 total
Sponsored By:
Vanilla Gorilla
I've lifted with and seen Big James lift in several meets. He is awesomely strong. But there is at least one falicy in the story. About only recently trying gear. I competed with him in 2005 and was announcing another meet he was in also in 2005 and he was geared up in a canvas squat suit (Inzer I think). He tried over 1000 but couldn't get close to depth at either meet. Great guy; but the info is a little off the time table...unless you call 6-6 1/2 years recent.
Proudly Sponsored by Titan Support Systems Inc. and 'Monster Barbell'
Training log: (Mastermonster's Quest For The Records)
The article is from that long ago Buddy. This was a bumped thread.
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this wiki
Thruster control was a manual control for a thruster. This control was located at the helm console. Occasionally, control could be transferred to another station on the main bridge of a starship. Loss of main power could result in a loss of thruster control. Emergency thrusters, which could operate on auxiliary power, didn't seem to need a thruster control.
In 1986, at the behest of Spock, the thruster control for the acceleration thrusters was transferred from Hikaru Sulu's console to the science console. Spock then manually fired the thrusters to push the HMS Bounty into a time warp.
In 2286, the thruster controls aboard the USS Saratoga were neutralized by the power drain caused by the transmisson of the Whale Probe. (Star Trek IV: The Voyage Home)


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Two Akin Gump Partners Named Among Los Angeles' Top 100 Lawyers
(Los Angeles, California) – Catherine A. Conway and Rex S. Heinke, partners at Akin Gump Strauss Hauer & Feld LLP in Los Angeles, have been named by the Los Angeles Business Journal to its list of the Top 100 Lawyers in Los Angeles.
In compiling its roster of lawyers regarded as "standouts" in 12 practice areas, the newspaper surveyed local recruiters, legal experts and lawyers.
Ms. Conway was recognized in the area of labor and employment; Mr. Heinke was recognized in litigation.
Founded in 1945, Akin Gump Strauss Hauer & Feld LLP, a leading international law firm, numbers more than 800 lawyers and advisors in the United States, Europe, Asia and the Middle East.
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Officials break ground for McDonald's in McArthur
By Paul McManis
Commoner Journal staff writer
McARTHUR — In about 90 days, Vinton County residents can visit the McArthur McDonald's, but after Monday's groundbreaking ceremony for the restaurant, officials claim a new beginning has already dawned in the community.
According to McArthur Mayor Jim Wooddell, McArthur has long been known as a community too small and less economically advantaged to open a national restaurant chain such as McDonald's, but he said at the groundbreaking event that stigma is now being removed.
"Any time you can dispel the myth that we are too small to have something of this magnitude, it's a positive thing," Wooddell said.
He said he believes the restaurant will not harm other businesses in the community, but will add growth and give more people in the area jobs without having to leave the county.
"This can be a real positive thing for the community. It will bring jobs and will be particularly good for young people," Wooddell said.
The new restaurant will be located at R&C Quickstop, located across from Vinton County High School on Route 50 just west of McArthur. Rick Hensler, co-owner of the property, said he has been working to bring the restaurant to the area for some time and is now happy to see it is on its way to providing another quality business to the area.
"I'll be even happier when this is finished. The ending is always better. It's a task that's finally going to get finished," Hensler said.
Another official happy to see the restaurant construction progress is McArthur McDonald's manager, Becky West-Lenegar.
West-Lenegar has been working at McDonald's restaurants in Wellston and Jackson for 12 years, and said she is prepared to jump into the role of the McArthur restaurant's general manager.
"I'm anxious. This is something I've worked on for 10 years. I'm glad to see it come to the community," West-Lenegar said.
She said she has great expectations for when the restaurant opens and is glad to see more opportunity given to people from Vinton County.
"It's going to be huge. I think it's going to be a big success all of the management team are from here and they all have a passion for this," West-Lenegar said.
McArthur McDonald's owner Brad Munn said it has been his goal from the beginning to bring as many people from Vinton County as possible to work the restaurant.
He said the process of shifting personnel has began and training will begin soon for people to work in both the McArthur and Wellston restaurants.
When the hiring process is complete, the McArthur restaurant provide jobs to between 45 and 50 people. The building will seat about 50 to 60 people and the parking lot will accommodate nearly 40 vehicles.
Jobs won't only be granted when the building is complete. Officials said construction for the McArthur restaurant will be completed by as many local contractors as possible.
With nearly $2 million invested from parties involved, some believe the addition of a McDonald's is sure to revitalize an area that has long been deemed too small to support national business chains.
"This is a great relief to a new beginning. … Absolutely an excellent addition for McArthur and the community," Hensler said.
Jean Fowler permalinkApril 16, 2012 4:02 pm
So happy to see McDonalds coming to Vinton County. This will bring much-needed jobs to our county, as well as another choice of places to eat.