Coevolutionary Free Lunches

NASA Technical Reports Server (NTRS)

Wolpert, David H.; Macready, William G.

2005-01-01

Recent work on the mathematical foundations of optimization has begun to uncover its rich structure. In particular, the "No Free Lunch" (NFL) theorems state that any two algorithms are equivalent when their performance is averaged across all possible problems. This highlights the need for exploiting problem-specific knowledge to achieve better than random performance. In this paper we present a general framework covering more search scenarios. In addition to the optimization scenarios addressed in the NFL results, this framework covers multi-armed bandit problems and evolution of multiple co-evolving players. As a particular instance of the latter, it covers "self-play" problems. In these problems the set of players work together to produce a champion, who then engages one or more antagonists in a subsequent multi-player game. In contrast to the traditional optimization case where the NFL results hold, we show that in self-play there are free lunches: in coevolution some algorithms have better performance than other algorithms, averaged across all possible problems. We consider the implications of these results to biology where there is no champion.

Amoeba-inspired Tug-of-War algorithms for exploration-exploitation dilemma in extended Bandit Problem.

PubMed

Aono, Masashi; Kim, Song-Ju; Hara, Masahiko; Munakata, Toshinori

2014-03-01

The true slime mold Physarum polycephalum, a single-celled amoeboid organism, is capable of efficiently allocating a constant amount of intracellular resource to its pseudopod-like branches that best fit the environment where dynamic light stimuli are applied. Inspired by the resource allocation process, the authors formulated a concurrent search algorithm, called the Tug-of-War (TOW) model, for maximizing the profit in the multi-armed Bandit Problem (BP). A player (gambler) of the BP should decide as quickly and accurately as possible which slot machine to invest in out of the N machines and faces an "exploration-exploitation dilemma." The dilemma is a trade-off between the speed and accuracy of the decision making that are conflicted objectives. The TOW model maintains a constant intracellular resource volume while collecting environmental information by concurrently expanding and shrinking its branches. The conservation law entails a nonlocal correlation among the branches, i.e., volume increment in one branch is immediately compensated by volume decrement(s) in the other branch(es). Owing to this nonlocal correlation, the TOW model can efficiently manage the dilemma. In this study, we extend the TOW model to apply it to a stretched variant of BP, the Extended Bandit Problem (EBP), which is a problem of selecting the best M-tuple of the N machines. We demonstrate that the extended TOW model exhibits better performances for 2-tuple-3-machine and 2-tuple-4-machine instances of EBP compared with the extended versions of well-known algorithms for BP, the ϵ-Greedy and SoftMax algorithms, particularly in terms of its short-term decision-making capability that is essential for the survival of the amoeba in a hostile environment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Action Centered Contextual Bandits.

PubMed

Greenewald, Kristjan; Tewari, Ambuj; Klasnja, Predrag; Murphy, Susan

2017-12-01

Contextual bandits have become popular as they offer a middle ground between very simple approaches based on multi-armed bandits and very complex approaches using the full power of reinforcement learning. They have demonstrated success in web applications and have a rich body of associated theoretical guarantees. Linear models are well understood theoretically and preferred by practitioners because they are not only easily interpretable but also simple to implement and debug. Furthermore, if the linear model is true, we get very strong performance guarantees. Unfortunately, in emerging applications in mobile health, the time-invariant linear model assumption is untenable. We provide an extension of the linear model for contextual bandits that has two parts: baseline reward and treatment effect. We allow the former to be complex but keep the latter simple. We argue that this model is plausible for mobile health applications. At the same time, it leads to algorithms with strong performance guarantees as in the linear model setting, while still allowing for complex nonlinear baseline modeling. Our theory is supported by experiments on data gathered in a recently concluded mobile health study.

Tug-of-war model for the two-bandit problem: nonlocally-correlated parallel exploration via resource conservation.

PubMed

Kim, Song-Ju; Aono, Masashi; Hara, Masahiko

2010-07-01

We propose a model - the "tug-of-war (TOW) model" - to conduct unique parallel searches using many nonlocally-correlated search agents. The model is based on the property of a single-celled amoeba, the true slime mold Physarum, which maintains a constant intracellular resource volume while collecting environmental information by concurrently expanding and shrinking its branches. The conservation law entails a "nonlocal correlation" among the branches, i.e., volume increment in one branch is immediately compensated by volume decrement(s) in the other branch(es). This nonlocal correlation was shown to be useful for decision making in the case of a dilemma. The multi-armed bandit problem is to determine the optimal strategy for maximizing the total reward sum with incompatible demands, by either exploiting the rewards obtained using the already collected information or exploring new information for acquiring higher payoffs involving risks. Our model can efficiently manage the "exploration-exploitation dilemma" and exhibits good performances. The average accuracy rate of our model is higher than those of well-known algorithms such as the modified -greedy algorithm and modified softmax algorithm, especially, for solving relatively difficult problems. Moreover, our model flexibly adapts to changing environments, a property essential for living organisms surviving in uncertain environments.

Single-photon decision maker

NASA Astrophysics Data System (ADS)

Naruse, Makoto; Berthel, Martin; Drezet, Aurélien; Huant, Serge; Aono, Masashi; Hori, Hirokazu; Kim, Song-Ju

2015-08-01

Decision making is critical in our daily lives and for society in general and is finding evermore practical applications in information and communication technologies. Herein, we demonstrate experimentally that single photons can be used to make decisions in uncertain, dynamically changing environments. Using a nitrogen-vacancy in a nanodiamond as a single-photon source, we demonstrate the decision-making capability by solving the multi-armed bandit problem. This capability is directly and immediately associated with single-photon detection in the proposed architecture, leading to adequate and adaptive autonomous decision making. This study makes it possible to create systems that benefit from the quantum nature of light to perform practical and vital intelligent functions.

Coevolutionary Free Lunches

NASA Technical Reports Server (NTRS)

Wolpert, David H.; Macready, William G.

2005-01-01

Recent work on the foundations of optimization has begun to uncover its underlying rich structure. In particular, the "No Free Lunch" (NFL) theorems [WM97] state that any two algorithms are equivalent when their performance is averaged across all possible problems. This highlights the need for exploiting problem-specific knowledge to achieve better than random performance. In this paper we present a general framework covering most search scenarios. In addition to the optimization scenarios addressed in the NFL results, this framework covers multi-armed bandit problems and evolution of multiple co-evolving agents. As a particular instance of the latter, it covers "self-play" problems. In these problems the agents work together to produce a champion, who then engages one or more antagonists in a subsequent multi-player game In contrast to the traditional optimization case where the NFL results hold, we show that in self-play there are free lunches: in coevolution some algorithms have better performance than other algorithms, averaged across all possible problems. However in the typical coevolutionary scenarios encountered in biology, where there is no champion, NFL still holds.

A multi-armed bandit approach to superquantile selection

DTIC Science & Technology

2017-06-01

decision learning, machine learning, intelligence processing, intelligence cycle, quantitative finance. 15. NUMBER OF PAGES 73 16. PRICE CODE 17...fulfillment of the requirements for the degree of MASTER OF SCIENCE IN OPERATIONS RESEARCH from the NAVAL POSTGRADUATE SCHOOL June 2017 Approved by...Roberto S. Szechtman Thesis Advisor Michael P. Atkinson Second Reader Patricia A. Jacobs Chair, Operations Research Department iii THIS PAGE

Modeling Human Performance in Restless Bandits with Particle Filters

ERIC Educational Resources Information Center

Yi, Sheng Kung M.; Steyvers, Mark; Lee, Michael

2009-01-01

Bandit problems provide an interesting and widely-used setting for the study of sequential decision-making. In their most basic form, bandit problems require people to choose repeatedly between a small number of alternatives, each of which has an unknown rate of providing reward. We investigate restless bandit problems, where the distributions of…

Approximate Solutions for Certain Optimal Stopping Problems

DTIC Science & Technology

1978-01-05

one-armed bandit problem) has arisen in a number of statistical applications (Chernoff and Ray (1965);, Chernoff (±9&]), Mallik (1971)): Let X(t... Mallik (1971) and Chernoff (1972). These previous approximations were determined without the benefit of the "correction for continuity" given in (5.1...Vol. 1, 3rd edition, John Wiley and Sons, Inc., New York» 7. Mallik , A.K» (1971), "Sequential estimation of the common mean of two normal

Decision-making without a brain: how an amoeboid organism solves the two-armed bandit.

PubMed

Reid, Chris R; MacDonald, Hannelore; Mann, Richard P; Marshall, James A R; Latty, Tanya; Garnier, Simon

2016-06-01

Several recent studies hint at shared patterns in decision-making between taxonomically distant organisms, yet few studies demonstrate and dissect mechanisms of decision-making in simpler organisms. We examine decision-making in the unicellular slime mould Physarum polycephalum using a classical decision problem adapted from human and animal decision-making studies: the two-armed bandit problem. This problem has previously only been used to study organisms with brains, yet here we demonstrate that a brainless unicellular organism compares the relative qualities of multiple options, integrates over repeated samplings to perform well in random environments, and combines information on reward frequency and magnitude in order to make correct and adaptive decisions. We extend our inquiry by using Bayesian model selection to determine the most likely algorithm used by the cell when making decisions. We deduce that this algorithm centres around a tendency to exploit environments in proportion to their reward experienced through past sampling. The algorithm is intermediate in computational complexity between simple, reactionary heuristics and calculation-intensive optimal performance algorithms, yet it has very good relative performance. Our study provides insight into ancestral mechanisms of decision-making and suggests that fundamental principles of decision-making, information processing and even cognition are shared among diverse biological systems. © 2016 The Authors.

Nash Equilibrium of Social-Learning Agents in a Restless Multiarmed Bandit Game.

PubMed

Nakayama, Kazuaki; Hisakado, Masato; Mori, Shintaro

2017-05-16

We study a simple model for social-learning agents in a restless multiarmed bandit (rMAB). The bandit has one good arm that changes to a bad one with a certain probability. Each agent stochastically selects one of the two methods, random search (individual learning) or copying information from other agents (social learning), using which he/she seeks the good arm. Fitness of an agent is the probability to know the good arm in the steady state of the agent system. In this model, we explicitly construct the unique Nash equilibrium state and show that the corresponding strategy for each agent is an evolutionarily stable strategy (ESS) in the sense of Thomas. It is shown that the fitness of an agent with ESS is superior to that of an asocial learner when the success probability of social learning is greater than a threshold determined from the probability of success of individual learning, the probability of change of state of the rMAB, and the number of agents. The ESS Nash equilibrium is a solution to Rogers' paradox.

Role of dopamine D2 receptors in optimizing choice strategy in a dynamic and uncertain environment

PubMed Central

Kwak, Shinae; Huh, Namjung; Seo, Ji-Seon; Lee, Jung-Eun; Han, Pyung-Lim; Jung, Min W.

2014-01-01

In order to investigate roles of dopamine receptor subtypes in reward-based learning, we examined choice behavior of dopamine D1 and D2 receptor-knockout (D1R-KO and D2R-KO, respectively) mice in an instrumental learning task with progressively increasing reversal frequency and a dynamic two-armed bandit task. Performance of D2R-KO mice was progressively impaired in the former as the frequency of reversal increased and profoundly impaired in the latter even with prolonged training, whereas D1R-KO mice showed relatively minor performance deficits. Choice behavior in the dynamic two-armed bandit task was well explained by a hybrid model including win-stay-lose-switch and reinforcement learning terms. A model-based analysis revealed increased win-stay, but impaired value updating and decreased value-dependent action selection in D2R-KO mice, which were detrimental to maximizing rewards in the dynamic two-armed bandit task. These results suggest an important role of dopamine D2 receptors in learning from past choice outcomes for rapid adjustment of choice behavior in a dynamic and uncertain environment. PMID:25389395

Budgeted Interactive Learning

DTIC Science & Technology

2017-06-15

the methodology of reducing the online-algorithm-selecting problem as a contextual bandit problem, which is yet another interactive learning...KH2016a] Kuan-Hao Huang and Hsuan-Tien Lin. Linear upper confidence bound algorithm for contextual bandit problem with piled rewards. In Proceedings

Cosmic bandits: Exploration versus exploitation in CMB B-mode experiments

NASA Astrophysics Data System (ADS)

Kovetz, Ely D.; Kamionkowski, Marc

2016-02-01

A preferred method to detect the curl-component, or B-mode, signature of inflationary gravitational waves (IGWs) in the cosmic microwave background (CMB) polarization, in the absence of foregrounds and lensing, is a prolonged integration over a single patch of sky of a few square degrees. In practice, however, foregrounds abound and the sensitivity to B modes can be improved considerably by finding the region of sky cleanest of foregrounds. The best strategy to detect B modes thus involves a tradeoff between exploration (to find lower-foreground patches) and exploitation (through prolonged integration). This problem is akin to the multi-armed bandit (MAB) problem in probability theory, wherein a gambler faces a series of slot machines with unknown winning odds and must develop a strategy to maximize his/her winnings with some finite number of pulls. While the optimal MAB strategy remains to be determined, a number of algorithms have been developed in an effort to maximize the winnings. Here, based on this resemblance, we tackle the search for IGW B modes with single frequency experiments in the presence of spatially varying foregrounds by developing adaptive survey strategies to optimize the sensitivity to IGW B modes. We demonstrate, using realistic foreground models and taking lensing-induced B modes into account, that adaptive experiments can substantially improve the upper bound on the tensor-to-scalar ratio (by factors of 2 and 3 in single frequency experiments, and possibly even more). Similar techniques can be applied to other surveys, including 21-cm measurements of signatures of the epoch of reionization, searches for a stochastic primordial gravitational wave background, deep-field imaging by the James Webb Space Telescope or various radio interferometers, and transient follow-up searches.

Introducing a Method for Calculating the Allocation of Attention in a Cognitive “Two-Armed Bandit” Procedure: Probability Matching Gives Way to Maximizing

PubMed Central

Heyman, Gene M.; Grisanzio, Katherine A.; Liang, Victor

2016-01-01

We tested whether principles that describe the allocation of overt behavior, as in choice experiments, also describe the allocation of cognition, as in attention experiments. Our procedure is a cognitive version of the “two-armed bandit choice procedure.” The two-armed bandit procedure has been of interest to psychologistsand economists because it tends to support patterns of responding that are suboptimal. Each of two alternatives provides rewards according to fixed probabilities. The optimal solution is to choose the alternative with the higher probability of reward on each trial. However, subjects often allocate responses so that the probability of a response approximates its probability of reward. Although it is this result which has attracted most interest, probability matching is not always observed. As a function of monetary incentives, practice, and individual differences, subjects tend to deviate from probability matching toward exclusive preference, as predicted by maximizing. In our version of the two-armed bandit procedure, the monitor briefly displayed two, small adjacent stimuli that predicted correct responses according to fixed probabilities, as in a two-armed bandit procedure. We show that in this setting, a simple linear equation describes the relationship between attention and correct responses, and that the equation’s solution is the allocation of attention between the two stimuli. The calculations showed that attention allocation varied as a function of the degree to which the stimuli predicted correct responses. Linear regression revealed a strong correlation (r = 0.99) between the predictiveness of a stimulus and the probability of attending to it. Nevertheless there were deviations from probability matching, and although small, they were systematic and statistically significant. As in choice studies, attention allocation deviated toward maximizing as a function of practice, feedback, and incentives. Our approach also predicts the frequency of correct guesses and the relationship between attention allocation and response latencies. The results were consistent with these two predictions, the assumptions of the equations used to calculate attention allocation, and recent studies which show that predictiveness and reward are important determinants of attention. PMID:27014109

Proximity Navigation of Highly Constrained Spacecraft

NASA Technical Reports Server (NTRS)

Scarritt, S.; Swartwout, M.

2007-01-01

Bandit is a 3-kg automated spacecraft in development at Washington University in St. Louis. Bandit's primary mission is to demonstrate proximity navigation, including docking, around a 25-kg student-built host spacecraft. However, because of extreme constraints in mass, power and volume, traditional sensing and actuation methods are not available. In particular, Bandit carries only 8 fixed-magnitude cold-gas thrusters to control its 6 DOF motion. Bandit lacks true inertial sensing, and the ability to sense position relative to the host has error bounds that approach the size of the Bandit itself. Some of the navigation problems are addressed through an extremely robust, error-tolerant soft dock. In addition, we have identified a control methodology that performs well in this constrained environment: behavior-based velocity potential functions, which use a minimum-seeking method similar to Lyapunov functions. We have also adapted the discrete Kalman filter for use on Bandit for position estimation and have developed a similar measurement vs. propagation weighting algorithm for attitude estimation. This paper provides an overview of Bandit and describes the control and estimation approach. Results using our 6DOF flight simulator are provided, demonstrating that these methods show promise for flight use.

Optimization through satisficing with prospects

NASA Astrophysics Data System (ADS)

Oyo, Kuratomo; Takahashi, Tatsuji

2017-07-01

As the broadening scope of reinforcement learning calls for a rational and more efficient heuristics, we test a satisficing strategy named RS, based on the theory of bounded rationality that considers the limited resources in agents. In K-armed bandit problems, despite its simpler form than the previous formalization of satisficing, RS shows better-than-optimal performances when the optimal aspiration level is given. We also show that RS shows a scalability for the number of actions, K, and an adaptability in the face of an infinite number of actions. It may be an efficient means for online learning in a complex or real environments.

Modeling Human Performance in Restless Bandits with Particle Filters (Preprint)

DTIC Science & Technology

2009-01-01

respond to changes ( Gallistel , 2001). Here, we use a particle filter approach to finding solutions to the restless bandit problem. Particle...Experimental Psychology: Learning, Memory, and Cognition, 10(2), 258-270. Gallistel , C. R., Mark, T., King, A., & Latham, P. E. (2001). The rat

Phase transition of social learning collectives and the echo chamber.

PubMed

Mori, Shintaro; Nakayama, Kazuaki; Hisakado, Masato

2016-11-01

We study a simple model for social learning agents in a restless multiarmed bandit. There are N agents, and the bandit has M good arms that change to bad with the probability q_{c}/N. If the agents do not know a good arm, they look for it by a random search (with the success probability q_{I}) or copy the information of other agents' good arms (with the success probability q_{O}) with probabilities 1-p or p, respectively. The distribution of the agents in M good arms obeys the Yule distribution with the power-law exponent 1+γ in the limit N,M→∞, and γ=1+(1-p)q_{I}/pq_{O}. The system shows a phase transition at p_{c}=q_{I}/q_{I}+q_{o}. For pp_{c}), the variance of N_{1} per agent is finite (diverges as ∝N^{2-γ} with N). There is a threshold value N_{s} for the system size that scales as lnN_{s}∝1/(γ-1). The expected value of the number of the agents with a good arm N_{1} increases with p for N>N_{s}. For p>p_{c} and N

Towards a Validation of the Three Pathways Model of Pathological Gambling.

PubMed

Valleur, Marc; Codina, Irène; Vénisse, Jean-Luc; Romo, Lucia; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Gorsane, Mohamed-Ali; Guilleux, Alice; Grall-Bronnec, Marie; Challet-Bouju, Gaëlle

2016-06-01

With the aim of validating the three pathways hypothesis of pathological gambling (Blaszczynski and Nower in Addiction 97:487-499, 2002) 372 pathological gamblers meeting DSM IV (2000) criteria were assessed via a structured clinical interview as well as being subjected to personality tests and evaluation of their gambling practices. Our results show that it is possible to identify three subgroups corresponding to the three pathways: behaviourally conditioned problem gamblers, emotionally vulnerable problem gamblers and antisocial impulsivist problem gamblers. Our results particularly demonstrate that impulsivist gamblers preferentially choose semi-skilful gambling (horse racing and sports gambling) whereas emotionally vulnerable gamblers are significantly more attracted to games of chance (one-armed bandits, scratch cards, etc.) This led us to propose a functional presentation of the three pathways model which differs somewhat from the Blaszczynski and Nower presentation.

Efficient decision-making by volume-conserving physical object

NASA Astrophysics Data System (ADS)

Kim, Song-Ju; Aono, Masashi; Nameda, Etsushi

2015-08-01

Decision-making is one of the most important intellectual abilities of not only humans but also other biological organisms, helping their survival. This ability, however, may not be limited to biological systems and may be exhibited by physical systems. Here we demonstrate that any physical object, as long as its volume is conserved when coupled with suitable operations, provides a sophisticated decision-making capability. We consider the multi-armed bandit problem (MBP), the problem of finding, as accurately and quickly as possible, the most profitable option from a set of options that gives stochastic rewards. Efficient MBP solvers are useful for many practical applications, because MBP abstracts a variety of decision-making problems in real-world situations in which an efficient trial-and-error is required. These decisions are made as dictated by a physical object, which is moved in a manner similar to the fluctuations of a rigid body in a tug-of-war (TOW) game. This method, called ‘TOW dynamics’, exhibits higher efficiency than conventional reinforcement learning algorithms. We show analytical calculations that validate statistical reasons for TOW dynamics to produce the high performance despite its simplicity. These results imply that various physical systems in which some conservation law holds can be used to implement an efficient ‘decision-making object’. The proposed scheme will provide a new perspective to open up a physics-based analog computing paradigm and to understanding the biological information-processing principles that exploit their underlying physics.

Foundations of Sequential Learning

DTIC Science & Technology

2018-02-01

is not sufficient to estimate the payoff. The learned must use a strategy that balances exploration (learning new information by pulling arms that...specifications, or other data does not license the holder or any other person or corporation ; or convey any rights or permission to manufacture, use, or sell any...ABSTRACT This report summarizes the research done under FA8750-16-2-0173. This research advanced understanding of bandit algorithms and exploration in

Sub-Saharan Africa Report

DTIC Science & Technology

1987-02-20

from Tanzania; and the worsening of the country’s social and economic crisis, wherein famine has already affected millions of people, creating a...life of our citizens. As everyone is aware, the hunger and poverty have contiuued. The 60,000 Adventists in the country were as rauch affected by the... affected by the criminal actions of the armed bandits, the security system has been strengthened. This is being done by militiamen, together with

Online matching with queueing dynamics.

DOT National Transportation Integrated Search

2016-12-01

We consider a variant of the multiarmed bandit problem where jobs queue for service, and service rates of different servers may be unknown. We study algorithms that minimize queue-regret: the (expected) difference between the queue-lengths obtained b...

Improved performance in NASTRAN (R)

NASA Technical Reports Server (NTRS)

Chan, Gordon C.

1989-01-01

Three areas of improvement in COSMIC/NASTRAN, 1989 release, were incorporated recently that make the analysis program run faster on large problems. Actual log files and actual timings on a few test samples that were run on IBM, CDC, VAX, and CRAY computers were compiled. The speed improvement is proportional to the problem size and number of continuation cards. Vectorizing certain operations in BANDIT, makes BANDIT run twice as fast in some large problems using structural elements with many node points. BANDIT is a built-in NASTRAN processor that optimizes the structural matrix bandwidth. The VAX matrix packing routine BLDPK was modified so that it is now packing a column of a matrix 3 to 9 times faster. The denser and bigger the matrix, the greater is the speed improvement. This improvement makes a host of routines and modules that involve matrix operation run significantly faster, and saves disc space for dense matrices. A UNIX version, converted from 1988 COSMIC/NASTRAN, was tested successfully on a Silicon Graphics computer using the UNIX V Operating System, with Berkeley 4.3 Extensions. The Utility Modules INPUTT5 and OUTPUT5 were expanded to handle table data, as well as matrices. Both INPUTT5 and OUTPUT5 are general input/output modules that read and write FORTRAN files with or without format. More user informative messages are echoed from PARAMR, PARAMD, and SCALAR modules to ensure proper data values and data types being handled. Two new Utility Modules, GINOFILE and DATABASE, were written for the 1989 release. Seven rigid elements are added to COSMIC/NASTRAN. They are: CRROD, CRBAR, CRTRPLT, CRBE1, CRBE2, CRBE3, and CRSPLINE.

Women's experiences in the armed conflict situation in Sudan.

PubMed

1999-01-01

The negative impact of war is apparent at various levels of the Sudanese society. Economic, social, and political instability is occurring on a large scale and the most vulnerable groups are women and children. This report aimed to document women's human rights violations in the ongoing armed conflict situation in Sudan, with the emphasis on rape; investigate the forms of violence against women in a situation of armed conflict; present testimonies of women survivors; and use the document for advocacy. A total of 20 testimonies were obtained, which clearly indicated that rape is a systematic practice in areas of conflict regardless of whether the Sudanese People's Liberation Army, the Khartoum government, or bandit groups that take advantage of the chaos, have attacked civilians. In view of this, regional agencies should show more seriousness in finding solutions for the war, and perpetrators of rape should be brought to justice so as to change the perception of rape as an unfortunate but inevitable side effect of war.

The involvement of model-based but not model-free learning signals during observational reward learning in the absence of choice.

PubMed

Dunne, Simon; D'Souza, Arun; O'Doherty, John P

2016-06-01

A major open question is whether computational strategies thought to be used during experiential learning, specifically model-based and model-free reinforcement learning, also support observational learning. Furthermore, the question of how observational learning occurs when observers must learn about the value of options from observing outcomes in the absence of choice has not been addressed. In the present study we used a multi-armed bandit task that encouraged human participants to employ both experiential and observational learning while they underwent functional magnetic resonance imaging (fMRI). We found evidence for the presence of model-based learning signals during both observational and experiential learning in the intraparietal sulcus. However, unlike during experiential learning, model-free learning signals in the ventral striatum were not detectable during this form of observational learning. These results provide insight into the flexibility of the model-based learning system, implicating this system in learning during observation as well as from direct experience, and further suggest that the model-free reinforcement learning system may be less flexible with regard to its involvement in observational learning. Copyright © 2016 the American Physiological Society.

Myths and Realities of Minimum Force in British Counterinsurgency Doctrine and Practice

DTIC Science & Technology

2013-03-01

into a cinema .127 The list goes on. Administratively, the local civil authorities did little to deter security forces from fighting the...the bandits.” This puts in a nutshell the problem of how to convince somebody who thinks like this without descending to Japanese methods. On the

The Role of Intelligence in Social Learning.

PubMed

Vostroknutov, Alexander; Polonio, Luca; Coricelli, Giorgio

2018-05-02

Studies in cultural evolution have uncovered many types of social learning strategies that are adaptive in certain environments. The efficiency of these strategies also depends on the individual characteristics of both the observer and the demonstrator. We investigate the relationship between intelligence and the ways social and individual information is utilised to make decisions in an uncertain environment. We measure fluid intelligence and study experimentally how individuals learn from observing the choices of a demonstrator in a 2-armed bandit problem with changing probabilities of a reward. Participants observe a demonstrator with high or low fluid intelligence. In some treatments they are aware of the intelligence score of the demonstrator and in others they are not. Low fluid intelligence individuals imitate the demonstrator more when her fluid intelligence is known than when it is not. Conversely, individuals with high fluid intelligence adjust their use of social information, as the observed behaviour changes, independently of the knowledge of the intelligence of the demonstrator. We provide evidence that intelligence determines how social and individual information is integrated in order to make choices in a changing uncertain environment.

National Symposium: Surface Navy Leading the Way (5th) Held at Washington, DC on 26-29 October 1992

DTIC Science & Technology

1992-10-29

nation. We all hope that in the days and years ahead a grateful nation continues to be grateful, and will not forget the price we paid for this... skimming threats. The Outlaw Bandit Program will continue. This program reduces the radar cross section of combatants significantly and increases the...Weapon Systems to provide a precision, multi-mode strike Cruise missile with an imaging seeker and hard target penetrator warhead. 22 With the

The "Booty Bandit": A Social Role in a Juvenile Institution

ERIC Educational Resources Information Center

Bartollas, Clemens; And Others

1975-01-01

In the juvenile institution discussed in this paper, 15 youths are committed to sexual exploitation of weaker inmates. These "booty bandits" are older, black youths from the ghetto who avoid emotional involvement with their victims and merely use them for their own physical release. (Author)

Functional Contour-following via Haptic Perception and Reinforcement Learning.

PubMed

Hellman, Randall B; Tekin, Cem; van der Schaar, Mihaela; Santos, Veronica J

2018-01-01

Many tasks involve the fine manipulation of objects despite limited visual feedback. In such scenarios, tactile and proprioceptive feedback can be leveraged for task completion. We present an approach for real-time haptic perception and decision-making for a haptics-driven, functional contour-following task: the closure of a ziplock bag. This task is challenging for robots because the bag is deformable, transparent, and visually occluded by artificial fingertip sensors that are also compliant. A deep neural net classifier was trained to estimate the state of a zipper within a robot's pinch grasp. A Contextual Multi-Armed Bandit (C-MAB) reinforcement learning algorithm was implemented to maximize cumulative rewards by balancing exploration versus exploitation of the state-action space. The C-MAB learner outperformed a benchmark Q-learner by more efficiently exploring the state-action space while learning a hard-to-code task. The learned C-MAB policy was tested with novel ziplock bag scenarios and contours (wire, rope). Importantly, this work contributes to the development of reinforcement learning approaches that account for limited resources such as hardware life and researcher time. As robots are used to perform complex, physically interactive tasks in unstructured or unmodeled environments, it becomes important to develop methods that enable efficient and effective learning with physical testbeds.

A dynamic multiarmed bandit-gene expression programming hyper-heuristic for combinatorial optimization problems.

PubMed

Sabar, Nasser R; Ayob, Masri; Kendall, Graham; Qu, Rong

2015-02-01

Hyper-heuristics are search methodologies that aim to provide high-quality solutions across a wide variety of problem domains, rather than developing tailor-made methodologies for each problem instance/domain. A traditional hyper-heuristic framework has two levels, namely, the high level strategy (heuristic selection mechanism and the acceptance criterion) and low level heuristics (a set of problem specific heuristics). Due to the different landscape structures of different problem instances, the high level strategy plays an important role in the design of a hyper-heuristic framework. In this paper, we propose a new high level strategy for a hyper-heuristic framework. The proposed high-level strategy utilizes a dynamic multiarmed bandit-extreme value-based reward as an online heuristic selection mechanism to select the appropriate heuristic to be applied at each iteration. In addition, we propose a gene expression programming framework to automatically generate the acceptance criterion for each problem instance, instead of using human-designed criteria. Two well-known, and very different, combinatorial optimization problems, one static (exam timetabling) and one dynamic (dynamic vehicle routing) are used to demonstrate the generality of the proposed framework. Compared with state-of-the-art hyper-heuristics and other bespoke methods, empirical results demonstrate that the proposed framework is able to generalize well across both domains. We obtain competitive, if not better results, when compared to the best known results obtained from other methods that have been presented in the scientific literature. We also compare our approach against the recently released hyper-heuristic competition test suite. We again demonstrate the generality of our approach when we compare against other methods that have utilized the same six benchmark datasets from this test suite.

Credit assignment in movement-dependent reinforcement learning

PubMed Central

Boggess, Matthew J.; Crossley, Matthew J.; Parvin, Darius; Ivry, Richard B.; Taylor, Jordan A.

2016-01-01

When a person fails to obtain an expected reward from an object in the environment, they face a credit assignment problem: Did the absence of reward reflect an extrinsic property of the environment or an intrinsic error in motor execution? To explore this problem, we modified a popular decision-making task used in studies of reinforcement learning, the two-armed bandit task. We compared a version in which choices were indicated by key presses, the standard response in such tasks, to a version in which the choices were indicated by reaching movements, which affords execution failures. In the key press condition, participants exhibited a strong risk aversion bias; strikingly, this bias reversed in the reaching condition. This result can be explained by a reinforcement model wherein movement errors influence decision-making, either by gating reward prediction errors or by modifying an implicit representation of motor competence. Two further experiments support the gating hypothesis. First, we used a condition in which we provided visual cues indicative of movement errors but informed the participants that trial outcomes were independent of their actual movements. The main result was replicated, indicating that the gating process is independent of participants’ explicit sense of control. Second, individuals with cerebellar degeneration failed to modulate their behavior between the key press and reach conditions, providing converging evidence of an implicit influence of movement error signals on reinforcement learning. These results provide a mechanistically tractable solution to the credit assignment problem. PMID:27247404

Credit assignment in movement-dependent reinforcement learning.

PubMed

McDougle, Samuel D; Boggess, Matthew J; Crossley, Matthew J; Parvin, Darius; Ivry, Richard B; Taylor, Jordan A

2016-06-14

When a person fails to obtain an expected reward from an object in the environment, they face a credit assignment problem: Did the absence of reward reflect an extrinsic property of the environment or an intrinsic error in motor execution? To explore this problem, we modified a popular decision-making task used in studies of reinforcement learning, the two-armed bandit task. We compared a version in which choices were indicated by key presses, the standard response in such tasks, to a version in which the choices were indicated by reaching movements, which affords execution failures. In the key press condition, participants exhibited a strong risk aversion bias; strikingly, this bias reversed in the reaching condition. This result can be explained by a reinforcement model wherein movement errors influence decision-making, either by gating reward prediction errors or by modifying an implicit representation of motor competence. Two further experiments support the gating hypothesis. First, we used a condition in which we provided visual cues indicative of movement errors but informed the participants that trial outcomes were independent of their actual movements. The main result was replicated, indicating that the gating process is independent of participants' explicit sense of control. Second, individuals with cerebellar degeneration failed to modulate their behavior between the key press and reach conditions, providing converging evidence of an implicit influence of movement error signals on reinforcement learning. These results provide a mechanistically tractable solution to the credit assignment problem.

A multi-stage drop-the-losers design for multi-arm clinical trials.

PubMed

Wason, James; Stallard, Nigel; Bowden, Jack; Jennison, Christopher

2017-02-01

Multi-arm multi-stage trials can improve the efficiency of the drug development process when multiple new treatments are available for testing. A group-sequential approach can be used in order to design multi-arm multi-stage trials, using an extension to Dunnett's multiple-testing procedure. The actual sample size used in such a trial is a random variable that has high variability. This can cause problems when applying for funding as the cost will also be generally highly variable. This motivates a type of design that provides the efficiency advantages of a group-sequential multi-arm multi-stage design, but has a fixed sample size. One such design is the two-stage drop-the-losers design, in which a number of experimental treatments, and a control treatment, are assessed at a prescheduled interim analysis. The best-performing experimental treatment and the control treatment then continue to a second stage. In this paper, we discuss extending this design to have more than two stages, which is shown to considerably reduce the sample size required. We also compare the resulting sample size requirements to the sample size distribution of analogous group-sequential multi-arm multi-stage designs. The sample size required for a multi-stage drop-the-losers design is usually higher than, but close to, the median sample size of a group-sequential multi-arm multi-stage trial. In many practical scenarios, the disadvantage of a slight loss in average efficiency would be overcome by the huge advantage of a fixed sample size. We assess the impact of delay between recruitment and assessment as well as unknown variance on the drop-the-losers designs.

Furia y Muerte: Los Bandidos Chicanos (Fury and Death: The Chicano Bandits). Monograph No. 4, Aztlan Publications.

ERIC Educational Resources Information Center

Castillo, Pedro, Ed.; Camarillo, Albert, Ed.

In the latter half of the nineteenth century five Chicano "bandidos" became prominant in Southwestern history. These "social bandits" were viewed by the dominant Anglo culture as outlaws and criminals; their people saw them as heroes and fighters for justice. Anglos had invaded Northern Mexico, disrupted the existing society,…

The Caballero Revisited: Postmodernity in "The Cisco Kid", "The Mask of Zorro", and "Shrek II"

ERIC Educational Resources Information Center

Leen, Catherine

2007-01-01

This article discusses the achievement of the postmodern caballero films and the relevance of the social bandit myth for Chicano resistance. The continued relevance of the social bandit myth is clearly demonstrated by "The Cisco Kid" and "The Mask of Zorro." Both films show how initially flawed or directionless characters can…

Development of Generic Aircrew Measures of Performance for Distributed Mission Training

DTIC Science & Technology

2003-03-31

collecte de données utiles sur les performances humaines représente des défis considérables. De plus, on ne trouvera pas deux essais d’IMD exactement...weapons Countered bandits offensive Very sound energy management and aircraft manoeuvering Quickly capitalized on offensive position...Effectively countered bandits offensive to a neutral position Ideal Aircraft energy management and manoeuvering Expeditiously capitalized on

The Coast Artillery Journal. Volume 74, Number 6, September-October 1931

DTIC Science & Technology

1931-10-01

Towns with the Primary Mission of Denying Such Towns to the Bandits This form of occupation became necessary in Nicar- agua in the summer and fall of 1927...such never materialized. Surprise Attacks on Bandit Camps Our first successful attack of this nature in Nicar- agua occurred in the first part of...complete reorganization of her military forces. Com- pulsory training is abolished. How difficult her situ - ation has become may be realized from the

Theory of choice in bandit, information sampling and foraging tasks.

PubMed

Averbeck, Bruno B

2015-03-01

Decision making has been studied with a wide array of tasks. Here we examine the theoretical structure of bandit, information sampling and foraging tasks. These tasks move beyond tasks where the choice in the current trial does not affect future expected rewards. We have modeled these tasks using Markov decision processes (MDPs). MDPs provide a general framework for modeling tasks in which decisions affect the information on which future choices will be made. Under the assumption that agents are maximizing expected rewards, MDPs provide normative solutions. We find that all three classes of tasks pose choices among actions which trade-off immediate and future expected rewards. The tasks drive these trade-offs in unique ways, however. For bandit and information sampling tasks, increasing uncertainty or the time horizon shifts value to actions that pay-off in the future. Correspondingly, decreasing uncertainty increases the relative value of actions that pay-off immediately. For foraging tasks the time-horizon plays the dominant role, as choices do not affect future uncertainty in these tasks.

Beyond the brotherhood: Skoal Bandits' role in the evolution of marketing moist smokeless tobacco pouches.

PubMed

Hendlin, Yogi H; Veffer, Jessica R; Lewis, M Jane; Ling, Pamela M

2017-01-01

Since 2006, "snus" smokeless tobacco has been sold in the U.S.. However, U.S. Smokeless Tobacco (USST) and Swedish Match developed and marketed pouched moist snuff tobacco (MST) since 1973. Analysis of previously secret tobacco documents, advertisements and trade press. USST partnered with Swedish Match, forming United Scandia International to develop pouch products as part of the "Lotus Project." Pouched MST was not commonly used, either in Sweden or the U.S. prior to the Lotus Project's innovation in 1973. The project aimed to transform smokeless tobacco from being perceived as an "unsightly habit of old men" into a relevant, socially acceptable urban activity, targeting 15-35 year-old men. While USST's initial pouched product "Good Luck," never gained mainstream traction, Skoal Bandits captured significant market share after its 1983 introduction. Internal market research found that smokers generally used Skoal Bandits in smokefree environments, yet continued to smoke cigarettes in other contexts. Over time, pouch products increasingly featured increased flavor, size, nicotine strength and user imagery variation. Marlboro and Camel Snus advertising mirrors historical advertising for Skoal Bandits, designed to recruit new users and smokers subjected to smokefree places. Despite serious efforts, pouched MST marketing has been unable to dispel its association with traditional smokeless tobacco stereotypes as macho and rural. Public education efforts to discourage new users and dual use of MST and cigarettes should emphasize that "new" pouch products are simply repackaging "old" smokeless tobacco.

Amygdala and Ventral Striatum Make Distinct Contributions to Reinforcement Learning.

PubMed

Costa, Vincent D; Dal Monte, Olga; Lucas, Daniel R; Murray, Elisabeth A; Averbeck, Bruno B

2016-10-19

Reinforcement learning (RL) theories posit that dopaminergic signals are integrated within the striatum to associate choices with outcomes. Often overlooked is that the amygdala also receives dopaminergic input and is involved in Pavlovian processes that influence choice behavior. To determine the relative contributions of the ventral striatum (VS) and amygdala to appetitive RL, we tested rhesus macaques with VS or amygdala lesions on deterministic and stochastic versions of a two-arm bandit reversal learning task. When learning was characterized with an RL model relative to controls, amygdala lesions caused general decreases in learning from positive feedback and choice consistency. By comparison, VS lesions only affected learning in the stochastic task. Moreover, the VS lesions hastened the monkeys' choice reaction times, which emphasized a speed-accuracy trade-off that accounted for errors in deterministic learning. These results update standard accounts of RL by emphasizing distinct contributions of the amygdala and VS to RL. Published by Elsevier Inc.

Amygdala and ventral striatum make distinct contributions to reinforcement learning

PubMed Central

Costa, Vincent D.; Monte, Olga Dal; Lucas, Daniel R.; Murray, Elisabeth A.; Averbeck, Bruno B.

2016-01-01

Summary Reinforcement learning (RL) theories posit that dopaminergic signals are integrated within the striatum to associate choices with outcomes. Often overlooked is that the amygdala also receives dopaminergic input and is involved in Pavlovian processes that influence choice behavior. To determine the relative contributions of the ventral striatum (VS) and amygdala to appetitive RL we tested rhesus macaques with VS or amygdala lesions on deterministic and stochastic versions of a two-arm bandit reversal learning task. When learning was characterized with a RL model relative to controls, amygdala lesions caused general decreases in learning from positive feedback and choice consistency. By comparison, VS lesions only affected learning in the stochastic task. Moreover, the VS lesions hastened the monkeys’ choice reaction times, which emphasized a speed-accuracy tradeoff that accounted for errors in deterministic learning. These results update standard accounts of RL by emphasizing distinct contributions of the amygdala and VS to RL. PMID:27720488

Summary of compliant and multi-arm control at NASA. Langley Research Center

NASA Technical Reports Server (NTRS)

Harrison, Fenton W.

1992-01-01

The topics are presented in viewgraph form and include the: single arm system, single arm axis system, single arm control systems, single arm hand controller axis system, single arm position axis system, single arm vision axis system, single arm force axis system, multi-arm system, multi-arm axis system, and the dual arm hand control axis system with control signals.

[A Multi-arm Placebo-controlled Study with Glutamic Acid Conducted in Rostock in 1953/1954].

PubMed

Häßler, Frank; Weirich, Steffen

2017-09-01

A Multi-arm Placebo-controlled Study with Glutamic Acid Conducted in Rostock in 1953/1954 Glutamic acid was commonly used in the treatment of intellectually disabled children in the 50s. Koch reported first results of an observation of 140 children treated with glutamic acid in 1952. In this line is the multi-arm placebo-controlled study reported here. The original study protocols were available. 58 children with speech problems who attending a school of special needs received glutamic acid, or vitamin B, or St.-John's-wort. The effect of glutamic acid was in few cases an improvement of attention. On the other hand restlessness and stutter increased. The majority of all reported a weight loss. The treatment with vitamin B showed a positive effect concerning concentration. The treatment with St.-John's wort was stopped caused by headache and vomiting in eight of nine cases. The results of the study reported here are unpublished. The reason may be that until the 60s the effects of glutamic acid in the treatment of intellectually disabled children were in generally overestimated.

Sparse Zero-Sum Games as Stable Functional Feature Selection

PubMed Central

Sokolovska, Nataliya; Teytaud, Olivier; Rizkalla, Salwa; Clément, Karine; Zucker, Jean-Daniel

2015-01-01

In large-scale systems biology applications, features are structured in hidden functional categories whose predictive power is identical. Feature selection, therefore, can lead not only to a problem with a reduced dimensionality, but also reveal some knowledge on functional classes of variables. In this contribution, we propose a framework based on a sparse zero-sum game which performs a stable functional feature selection. In particular, the approach is based on feature subsets ranking by a thresholding stochastic bandit. We provide a theoretical analysis of the introduced algorithm. We illustrate by experiments on both synthetic and real complex data that the proposed method is competitive from the predictive and stability viewpoints. PMID:26325268

Anhedonia and anxiety underlying depressive symptomatology have distinct effects on reward-based decision-making.

PubMed

Harlé, Katia M; Guo, Dalin; Zhang, Shunan; Paulus, Martin P; Yu, Angela J

2017-01-01

Depressive pathology, which includes both heightened negative affect (e.g., anxiety) and reduced positive affect (e.g., anhedonia), is known to be associated with sub-optimal decision-making, particularly in uncertain environments. Here, we use a computational approach to quantify and disambiguate how individual differences in these affective measures specifically relate to different aspects of learning and decision-making in reward-based choice behavior. Fifty-three individuals with a range of depressed mood completed a two-armed bandit task, in which they choose between two arms with fixed but unknown reward rates. The decision-making component, which chooses among options based on current expectations about reward rates, is modeled by two different decision policies: a learning-independent Win-stay/Lose-shift (WSLS) policy that ignores all previous experiences except the last trial, and Softmax, which prefers the arm with the higher expected reward. To model the learning component for the Softmax choice policy, we use a Bayesian inference model, which updates estimated reward rates based on the observed history of trial outcomes. Softmax with Bayesian learning better fits the behavior of 55% of the participants, while the others are better fit by a learning-independent WSLS strategy. Among Softmax "users", those with higher anhedonia are less likely to choose the option estimated to be most rewarding. Moreover, the Softmax parameter mediates the inverse relationship between anhedonia and overall monetary gains. On the other hand, among WSLS "users", higher state anxiety correlates with increasingly better ability of WSLS, relative to Softmax, to explain subjects' trial-by-trial choices. In summary, there is significant variability among individuals in their reward-based, exploratory decision-making, and this variability is at least partly mediated in a very specific manner by affective attributes, such as hedonic tone and state anxiety.

Multi-Robot Assembly Strategies and Metrics.

PubMed

Marvel, Jeremy A; Bostelman, Roger; Falco, Joe

2018-02-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies.

Multi-Robot Assembly Strategies and Metrics

PubMed Central

MARVEL, JEREMY A.; BOSTELMAN, ROGER; FALCO, JOE

2018-01-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies. PMID:29497234

Effects of a Problem-Solving Intervention (COPE) on Quality of Life for Patients with Advanced Cancer on Clinical Trials and their Caregivers: Simultaneous Care Educational Intervention (SCEI): Linking Palliation and Clinical Trials

PubMed Central

Carducci, Michael; Loscalzo, Matthew J.; Linder, John; Greasby, Tamara; Beckett, Laurel A.

2011-01-01

Abstract Context Patients on investigational clinical trials and their caregivers experience poor quality of life (QOL), which declines as the disease progresses. Objective To examine the effect of a standardized cognitive–behavioral problem-solving educational intervention on the QOL of patients enrolled on investigational clinical trials and their caregivers. Design Prospective, multi-institution, randomized trial. QOL was measured repeatedly over 6 months. Participants Patients were simultaneously enrolled onto phase 1, 2, or 3 Institutional Review Board (IRB)-approved cancer clinical trials. Intervention Intervention arm dyads participated in three conjoint educational sessions during the first month, learning the COPE problem solving model. Nonintervention arm dyads received usual care. Outcome Measures Global QOL was measured by the City of Hope Quality of Life Instruments for Patients or Caregivers; problem solving skills were measured by the Social Problem Solving Inventory-Revised. Results The results are reported using the CONSORT statement. The analytic data set included 476 dyads including 1596 patient data points and 1576 care giver data points. Patient QOL showed no significant difference in the rate of change between the intervention and usual care arms (p = 0.70). Caregiver QOL scores in the intervention arm declined, but at less than half the rate in the control arm (p = 0.02). Conclusions The COPE intervention enabled the average caregiver to come much closer to stable QOL over the 6-month follow-up. Future studies should enroll subjects much earlier in the cancer illness trajectory, a common patient/caregiver theme. The maximum effect was seen in caregivers who completed the 6-month follow-up, suggesting that the impact may increase over time. PMID:21413846

Accounting for correlation in network meta-analysis with multi-arm trials.

PubMed

Franchini, A J; Dias, S; Ades, A E; Jansen, J P; Welton, N J

2012-06-01

Multi-arm trials (trials with more than two arms) are particularly valuable forms of evidence for network meta-analysis (NMA). Trial results are available either as arm-level summaries, where effect measures are reported for each arm, or as contrast-level summaries, where the differences in effect between arms compare with the control arm chosen for the trial. We show that likelihood-based inference in both contrast-level and arm-level formats is identical if there are only two-arm trials, but that if there are multi-arm trials, results from the contrast-level format will be incorrect unless correlations are accounted for in the likelihood. We review Bayesian and frequentist software for NMA with multi-arm trials that can account for this correlation and give an illustrative example of the difference in estimates that can be introduced if the correlations are not incorporated. We discuss methods of imputing correlations when they cannot be derived from the reported results and urge trialists to report the standard error for the control arm even if only contrast-level summaries are reported. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

Realization of an Ultra-thin Metasurface to Facilitate Wide Bandwidth, Wide Angle Beam Scanning.

PubMed

Bah, Alpha O; Qin, Pei-Yuan; Ziolkowski, Richard W; Cheng, Qiang; Guo, Y Jay

2018-03-19

A wide bandwidth, ultra-thin, metasurface is reported that facilitates wide angle beam scanning. Each unit cell of the metasurface contains a multi-resonant, strongly-coupled unequal arm Jerusalem cross element. This element consists of two bent-arm, orthogonal, capacitively loaded strips. The wide bandwidth of the metasurface is achieved by taking advantage of the strong coupling within and between its multi-resonant elements. A prototype of the proposed metasurface has been fabricated and measured. The design concept has been validated by the measured results. The proposed metasurface is able to alleviate the well-known problem of impedance mismatch caused by mutual coupling when the main beam of an array is scanned. In order to validate the wideband and wide scanning ability of the proposed metasurface, it is integrated with a wideband antenna array as a wide angle impedance matching element. The metasurface-array combination facilitates wide angle scanning over a 6:1 impedance bandwidth without the need for bulky dielectrics or multi-layered structures.

Exposure to bright light biases effort-based decisions.

PubMed

Bijleveld, Erik; Knufinke, Melanie

2018-06-01

Secreted in the evening and the night, melatonin suppresses activity of the mesolimbic dopamine pathway, a brain pathway involved in reward processing. However, exposure to bright light diminishes-or even prevents-melatonin secretion. Thus, we hypothesized that reward processing, in the evening, is more pronounced in bright light (vs. dim light). Healthy human participants carried out three tasks that tapped into various aspects of reward processing (effort expenditure for rewards task [EEfRT]; two-armed bandit task [2ABT]; balloon analogue risk task [BART). Brightness was manipulated within-subjects (bright vs. dim light), in separate evening sessions. During the EEfRT, participants used reward-value information more strongly when they were exposed to bright light (vs. dim light). This finding supported our hypothesis. However, exposure to bright light did not significantly affect task behavior on the 2ABT and the BART. While future research is necessary (e.g., to zoom in on working mechanisms), these findings have potential implications for the design of physical work environments. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Optimizing microstimulation using a reinforcement learning framework.

PubMed

Brockmeier, Austin J; Choi, John S; Distasio, Marcello M; Francis, Joseph T; Príncipe, José C

2011-01-01

The ability to provide sensory feedback is desired to enhance the functionality of neuroprosthetics. Somatosensory feedback provides closed-loop control to the motor system, which is lacking in feedforward neuroprosthetics. In the case of existing somatosensory function, a template of the natural response can be used as a template of desired response elicited by electrical microstimulation. In the case of no initial training data, microstimulation parameters that produce responses close to the template must be selected in an online manner. We propose using reinforcement learning as a framework to balance the exploration of the parameter space and the continued selection of promising parameters for further stimulation. This approach avoids an explicit model of the neural response from stimulation. We explore a preliminary architecture--treating the task as a k-armed bandit--using offline data recorded for natural touch and thalamic microstimulation, and we examine the methods efficiency in exploring the parameter space while concentrating on promising parameter forms. The best matching stimulation parameters, from k = 68 different forms, are selected by the reinforcement learning algorithm consistently after 334 realizations.

75 FR 9531 - Magnuson-Stevens Act Provisions; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

..., rod and reel, spear, trap, slurp gun, hand harvest. C. Charter fishery C. Bandit gear, buoy gear..., gillnet, hand harvest, seine, slurp gun, trap, spear, rod and reel, hook and line. 12. Recreational...

Design and analysis on robotic arm for serving hazard container

NASA Astrophysics Data System (ADS)

Razali, Zol Bahri; Kader, Mohamed Mydin M. Abdul; Yi, Khoo Zern; Daud, Mohd Hisam

2017-09-01

This paper presents about design, analyses development and fabrication of robotic arm for sorting multi-material. The major problem that urges the initiation of the project is the fact that manufacturing industry is growing at relatively faster rate. Most of the company produce high load robotic arm. Less company creates light weight, and affordable robotic arm. As the result, light weight and affordable robot is developing to cover this issue. Plastic material was used to construct the body of the robotic arm, and an optical sensor was implemented to provide basic recognition of object to be carried. The robotic arm used five servomotors for overall operation; four for its joints, and one for the gripping mechanism. The gripper was designed and fabricated using Perspex due to the light weight and high strength of the material. The operation of the robotic arm was governed by Basic Stamp programming sequence and the device was expected to differentiate material and other objects based on reflective theory, and perform subsequent operations afterwards. The SolidWorks was used to model the detail design of the robotic arm, and to simulate the motion of the device.

Correcting for multiple-testing in multi-arm trials: is it necessary and is it done?

PubMed

Wason, James M S; Stecher, Lynne; Mander, Adrian P

2014-09-17

Multi-arm trials enable the evaluation of multiple treatments within a single trial. They provide a way of substantially increasing the efficiency of the clinical development process. However, since multi-arm trials test multiple hypotheses, some regulators require that a statistical correction be made to control the chance of making a type-1 error (false-positive). Several conflicting viewpoints are expressed in the literature regarding the circumstances in which a multiple-testing correction should be used. In this article we discuss these conflicting viewpoints and review the frequency with which correction methods are currently used in practice. We identified all multi-arm clinical trials published in 2012 by four major medical journals. Summary data on several aspects of the trial design were extracted, including whether the trial was exploratory or confirmatory, whether a multiple-testing correction was applied and, if one was used, what type it was. We found that almost half (49%) of published multi-arm trials report using a multiple-testing correction. The percentage that corrected was higher for trials in which the experimental arms included multiple doses or regimens of the same treatments (67%). The percentage that corrected was higher in exploratory than confirmatory trials, although this is explained by a greater proportion of exploratory trials testing multiple doses and regimens of the same treatment. A sizeable proportion of published multi-arm trials do not correct for multiple-testing. Clearer guidance about whether multiple-testing correction is needed for multi-arm trials that test separate treatments against a common control group is required.

KARMA: the observation preparation tool for KMOS

NASA Astrophysics Data System (ADS)

Wegner, Michael; Muschielok, Bernard

2008-08-01

KMOS is a multi-object integral field spectrometer working in the near infrared which is currently being built for the ESO VLT by a consortium of UK and German institutes. It is capable of selecting up to 24 target fields for integral field spectroscopy simultaneously by means of 24 robotic pick-off arms. For the preparation of observations with KMOS a dedicated preparation tool KARMA ("KMOS Arm Allocator") will be provided which optimizes the assignment of targets to these arms automatically, thereby taking target priorities and several mechanical and optical constraints into account. For this purpose two efficient algorithms, both being able to cope with the underlying optimization problem in a different way, were developed. We present the concept and architecture of KARMA in general and the optimization algorithms in detail.

Dynamic modelling and parameter estimation of a hydraulic robot manipulator using a multi-objective genetic algorithm

NASA Astrophysics Data System (ADS)

Montazeri, A.; West, C.; Monk, S. D.; Taylor, C. J.

2017-04-01

This paper concerns the problem of dynamic modelling and parameter estimation for a seven degree of freedom hydraulic manipulator. The laboratory example is a dual-manipulator mobile robotic platform used for research into nuclear decommissioning. In contrast to earlier control model-orientated research using the same machine, the paper develops a nonlinear, mechanistic simulation model that can subsequently be used to investigate physically meaningful disturbances. The second contribution is to optimise the parameters of the new model, i.e. to determine reliable estimates of the physical parameters of a complex robotic arm which are not known in advance. To address the nonlinear and non-convex nature of the problem, the research relies on the multi-objectivisation of an output error single-performance index. The developed algorithm utilises a multi-objective genetic algorithm (GA) in order to find a proper solution. The performance of the model and the GA is evaluated using both simulated (i.e. with a known set of 'true' parameters) and experimental data. Both simulation and experimental results show that multi-objectivisation has improved convergence of the estimated parameters compared to the single-objective output error problem formulation. This is achieved by integrating the validation phase inside the algorithm implicitly and exploiting the inherent structure of the multi-objective GA for this specific system identification problem.

Theory and simulation of multi-channel interference (MCI) widely tunable lasers.

PubMed

Chen, Quanan; Lu, Qiaoyin; Guo, Weihua

2015-07-13

A novel design of an InP-based monolithic widely tunable laser, multi-channel interference (MCI) laser, is proposed and presented for the first time. The device is comprised of a gain section, a common phase section and a multi-channel interference section. The multi-channel interference section contains a 1x8 splitter based on cascaded 1 × 2 multi-mode interferometers (MMIs) and eight arms with unequal length difference. The rear part of each arm is integrated with a one-port multi-mode interference reflector (MIR). Mode selection of the MCI laser is realized by the constructive interference of the lights reflected back by the eight arms. Through optimizing the arm length difference, a tuning range of more than 40 nm covering the whole C band, a threshold current around 11.5 mA and an side-mode-suppression-ratio (SMSR) up to 48 dB have been predicted for this widely tunable laser. Detailed design principle and numerical simulation results are presented.

Development of induction current acquisition device based on ARM

NASA Astrophysics Data System (ADS)

Ji, Yanju; Liu, Xiyang; Huang, Wanyu; Yao, Jiang; Yuan, Guiyang; Hui, Luan; Guan, Shanshan

2018-03-01

We design an induction current acquisition device based on ARM in order to realize high resolution and high sampling rate of acquisition for the induction current in wire-loop. Considering its characteristics of fast attenuation and small signal amplitude, we use the method of multi-path fusion for noise suppression. In the paper, the design is carried out from three aspects of analog circuit and device selection, independent power supply structure and the electromagnetic interference suppression of high frequency. DMA and ping-pong buffer, as a new data transmission technology, solves real time storage problem of massive data. The performance parameters of ARM acquisition device are tested. The comparison test of ARM acquisition device and cRIO acquisition device is performed at different time constants. The results show that it has 120dB dynamic range, 47kHz bandwidth, 96kHz sampling rate, 5μV the smallest resolution, and its average error value is not more than 4%, which proves the high accuracy and stability of the device.

Mesomorphic properties of multi-arm chenodeoxycholic acid-derived liquid crystals

NASA Astrophysics Data System (ADS)

Dong, Liang; Yao, Miao; Wu, Shuang-jie; Yao, Dan-Shu; Hu, Jian-She; He, Xiao-zhi; Tian, Mei

2017-12-01

Four multi-arm liquid crystals (LCs) based on chenodeoxycholic acid, termed as 2G-PD, 2G-IB, 2G-BD and 5G-GC, respectively, have been synthesised by convergent method, which nematic LC, 6-(4-((4-ethoxybenzoyl)oxy)phenoxy)-6-oxohexanoic acid, was used as side arm, and chenodeoxycholic acid (CDCA) was used as the first core, 1,2-propanediol (PD), isosorbide (IB), 4,4‧-biphenyldiol (BD) and glucose (GC) were used as the second core, respectively. The first generation product, CDCA2EA, displayed cholesteric phase. The second generation products 2G-BD and 5G-GC displayed cholesteric phase, while 2G-PD and 2G-IB exhibited nematic phase. The multi-arm LC, 2G-IB, did not display cholesteric phase although the two cores were all chiral ones. The result indicated that chirality of the second core sometimes made the multi-arm LCs display nematic phase when cholesteric CDCA-derivative were introduced into the second core. Some attention should be paid on molecular conformation besides the introduction of chiral cores for multi-chiral-core LCs to obtain cholesteric phase.

Multi-Scale Modeling of an Integrated 3D Braided Composite with Applications to Helicopter Arm

NASA Astrophysics Data System (ADS)

Zhang, Diantang; Chen, Li; Sun, Ying; Zhang, Yifan; Qian, Kun

2017-10-01

A study is conducted with the aim of developing multi-scale analytical method for designing the composite helicopter arm with three-dimensional (3D) five-directional braided structure. Based on the analysis of 3D braided microstructure, the multi-scale finite element modeling is developed. Finite element analysis on the load capacity of 3D five-directional braided composites helicopter arm is carried out using the software ABAQUS/Standard. The influences of the braiding angle and loading condition on the stress and strain distribution of the helicopter arm are simulated. The results show that the proposed multi-scale method is capable of accurately predicting the mechanical properties of 3D braided composites, validated by the comparison the stress-strain curves of meso-scale RVCs. Furthermore, it is found that the braiding angle is an important factor affecting the mechanical properties of 3D five-directional braided composite helicopter arm. Based on the optimized structure parameters, the nearly net-shaped composite helicopter arm is fabricated using a novel resin transfer mould (RTM) process.

Octopus-inspired multi-arm robotic swimming.

PubMed

Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

2015-05-13

The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

Increased Survival Among HIV-Infected PWID Receiving a Multi-Level HIV Risk and Stigma Reduction Intervention: Results From a Randomized Controlled Trial.

PubMed

Go, Vivian F; Frangakis, Constantine; Le Minh, Nguyen; Ha, Tran Viet; Latkin, Carl A; Sripaipan, Teerada; Zelaya, Carla E; Davis, Wendy W; Celentano, David D; Quan, Vu Minh

2017-02-01

In Vietnam, where 58% of prevalent HIV cases are attributed to people who inject drugs, we evaluated whether a multi-level intervention could improve care outcomes and increase survival. We enrolled 455 HIV-infected males who inject drugs from 32 communes in Thai Nguyen Province. Communes were randomized to a community stigma reduction intervention or standard of care and then within each commune, to an individual enhanced counseling intervention or standard of care, resulting into 4 arms: Arm 1 (standard of care); Arm 2 (community intervention alone); Arm 3 (individual intervention alone); and Arm 4 (community + individual interventions). Follow-up was conducted at 6, 12, 18, and 24 months to assess survival. Overall mortality was 23% (n = 103/455) more than 2 years. There were no losses to follow-up for the mortality endpoint. Survival at 24 months was different across arms: Arm 4 (87%) vs Arm 1 (82%) vs Arm 2 (68%) vs Arm 3 (73%); log-rank test for comparison among arms: P = 0.001. Among those with CD4 cell count <200 cells/mm and not on antiretroviral therapy at baseline (n = 162), survival at 24 months was higher in Arm 4 (84%) compared with other arms (Arm 1: 61%; Arm 2: 50%; Arm 3: 53%; P-value = 0.002). Overall, Arm 4 (community + individual interventions) had increased uptake of antiretroviral therapy compared with Arms 1, 2, and 3. This multi-level behavioral intervention seemed to increase survival of HIV-infected participants more than a 2-year period. Relative to the standard of care, the greatest intervention effect was among those with lower CD4 cell counts.

Neural dynamic optimization for control systems. I. Background.

PubMed

Seong, C Y; Widrow, B

2001-01-01

The paper presents neural dynamic optimization (NDO) as a method of optimal feedback control for nonlinear multi-input-multi-output (MIMO) systems. The main feature of NDO is that it enables neural networks to approximate the optimal feedback solution whose existence dynamic programming (DP) justifies, thereby reducing the complexities of computation and storage problems of the classical methods such as DP. This paper mainly describes the background and motivations for the development of NDO, while the two other subsequent papers of this topic present the theory of NDO and demonstrate the method with several applications including control of autonomous vehicles and of a robot arm, respectively.

Neural dynamic optimization for control systems.III. Applications.

PubMed

Seong, C Y; Widrow, B

2001-01-01

For pt.II. see ibid., p. 490-501. The paper presents neural dynamic optimization (NDO) as a method of optimal feedback control for nonlinear multi-input-multi-output (MIMO) systems. The main feature of NDO is that it enables neural networks to approximate the optimal feedback solution whose existence dynamic programming (DP) justifies, thereby reducing the complexities of computation and storage problems of the classical methods such as DP. This paper demonstrates NDO with several applications including control of autonomous vehicles and of a robot-arm, while the two other companion papers of this topic describes the background for the development of NDO and present the theory of the method, respectively.

Neural dynamic optimization for control systems.II. Theory.

PubMed

Seong, C Y; Widrow, B

2001-01-01

The paper presents neural dynamic optimization (NDO) as a method of optimal feedback control for nonlinear multi-input-multi-output (MIMO) systems. The main feature of NDO is that it enables neural networks to approximate the optimal feedback solution whose existence dynamic programming (DP) justifies, thereby reducing the complexities of computation and storage problems of the classical methods such as DP. This paper mainly describes the theory of NDO, while the two other companion papers of this topic explain the background for the development of NDO and demonstrate the method with several applications including control of autonomous vehicles and of a robot arm, respectively.

Managing Enrollment Bandits: Recovering Enrollments Lost during Registration

ERIC Educational Resources Information Center

Head, Joe F.; Blake, Susan; Hughes, Thomas M.

2009-01-01

Good enrollment managers know that keeping current enrollment must be Job Number One and that maintaining enrollment must be the concern of all campus constituencies. However, a large number of students are "lost" during registration due to closed classes. Lost enrollments are a largely invisible phenomenon that represents frantic and…

50 CFR 600.725 - General prohibitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and reel, spear. 19. Summer Flounder, Scup, Black Sea Bass Fishery (FMP managed by MAFMC): A. Trawl...-Atlantic Fishery Management Council (MAFMC) 1. Summer Flounder, Scup, Black Sea Bass Fishery (FMP): A... reel, bandit gear, handline, spear, powerhead. B. Black sea bass trap and pot fishery B. Pot, trap. C...

50 CFR 600.725 - General prohibitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and reel, spear. 19. Summer Flounder, Scup, Black Sea Bass Fishery (FMP managed by MAFMC): A. Trawl...-Atlantic Fishery Management Council (MAFMC) 1. Summer Flounder, Scup, Black Sea Bass Fishery (FMP): A... reel, bandit gear, handline, spear, powerhead. B. Black sea bass trap and pot fishery B. Pot, trap. C...

50 CFR 600.725 - General prohibitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and reel, spear. 19. Summer Flounder, Scup, Black Sea Bass Fishery (FMP managed by MAFMC): A. Trawl...-Atlantic Fishery Management Council (MAFMC) 1. Summer Flounder, Scup, Black Sea Bass Fishery (FMP): A... reel, bandit gear, handline, spear, powerhead. B. Black sea bass trap and pot fishery B. Pot, trap. C...

77 FR 41442 - Agency Information Collection Activities: Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-13

... (ICR) to renew approval of the paperwork requirements for ``Bird Banding Lab (4 USGS forms).'' This..., (3) The Bird Banding Recovery Report, and one electronic database, Bandit. We will protect... its implementing regulations (43 CFR part 2), and under regulations at 30 CFR 250.197, ``Data and...

Human arm stiffness and equilibrium-point trajectory during multi-joint movement.

PubMed

Gomi, H; Kawato, M

1997-03-01

By using a newly designed high-performance manipulandum and a new estimation algorithm, we measured human multi-joint arm stiffness parameters during multi-joint point-to-point movements on a horizontal plane. This manipulandum allows us to apply a sufficient perturbation to subject's arm within a brief period during movement. Arm stiffness parameters were reliably estimated using a new algorithm, in which all unknown structural parameters could be estimated independent of arm posture (i.e., constant values under any arm posture). Arm stiffness during transverse movement was considerably greater than that during corresponding posture, but not during a longitudinal movement. Although the ratios of elbow, shoulder, and double-joint stiffness were varied in time, the orientation of stiffness ellipses during the movement did not change much. Equilibrium-point trajectories that were predicted from measured stiffness parameters and actual trajectories were slightly sinusoidally curved in Cartesian space and their velocity profiles were quite different from the velocity profiles of actual hand trajectories. This result contradicts the hypothesis that the brain does not take the dynamics into account in movement control depending on the neuromuscular servo mechanism; rather, it implies that the brain needs to acquire some internal models of controlled objects.

78 FR 15292 - Drawbridge Operation Regulations; Upper Mississippi River, Rock Island, IL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-11

... Operation Regulations; Upper Mississippi River, Rock Island, IL AGENCY: Coast Guard, DHS. ACTION: Notice of... schedule that governs the Rock Island Railroad and Highway Drawbridge, across the Upper Mississippi River, mile 482.9, at Rock Island, Illinois. The deviation is necessary to allow the River Bandits 5K Run/Walk...

Flexible trial design in practice - stopping arms for lack-of-benefit and adding research arms mid-trial in STAMPEDE: a multi-arm multi-stage randomized controlled trial

PubMed Central

2012-01-01

Background Systemic Therapy for Advanced or Metastatic Prostate cancer: Evaluation of Drug Efficacy (STAMPEDE) is a randomized controlled trial that follows a novel multi-arm, multi-stage (MAMS) design. We describe methodological and practical issues arising with (1) stopping recruitment to research arms following a pre-planned intermediate analysis and (2) adding a new research arm during the trial. Methods STAMPEDE recruits men who have locally advanced or metastatic prostate cancer who are starting standard long-term hormone therapy. Originally there were five research and one control arms, each undergoing a pilot stage (focus: safety, feasibility), three intermediate ‘activity’ stages (focus: failure-free survival), and a final ‘efficacy’ stage (focus: overall survival). Lack-of-sufficient-activity guidelines support the pairwise interim comparisons of each research arm against the control arm; these pre-defined activity cut-off becomes increasingly stringent over the stages. Accrual of further patients continues to the control arm and to those research arms showing activity and an acceptable safety profile. The design facilitates adding new research arms should sufficiently interesting agents emerge. These new arms are compared only to contemporaneously recruited control arm patients using the same intermediate guidelines in a time-delayed manner. The addition of new research arms is subject to adequate recruitment rates to support the overall trial aims. Results (1) Stopping Existing Therapy: After the second intermediate activity analysis, recruitment was discontinued to two research arms for lack-of-sufficient activity. Detailed preparations meant that changes were implemented swiftly at 100 international centers and recruitment continued seamlessly into Activity Stage III with 3 remaining research arms and the control arm. Further regulatory and ethical approvals were not required because this was already included in the initial trial design. (2) Adding New Therapy: An application to add a new research arm was approved by the funder, (who also organized peer review), industrial partner and regulatory and ethical bodies. This was all done in advance of any decision to stop current therapies. Conclusions The STAMPEDE experience shows that recruitment to a MAMS trial and mid-flow changes its design are achievable with good planning. This benefits patients and the scientific community as research treatments are evaluated in a more efficient and cost-effective manner. Trial registration ISRCTN78818544, NCT00268476 First patient into trial: 17 October 2005 First patient into abiraterone comparison: 15 November 2011 PMID:22978443

Flexible trial design in practice - stopping arms for lack-of-benefit and adding research arms mid-trial in STAMPEDE: a multi-arm multi-stage randomized controlled trial.

PubMed

Sydes, Matthew R; Parmar, Mahesh K B; Mason, Malcolm D; Clarke, Noel W; Amos, Claire; Anderson, John; de Bono, Johann; Dearnaley, David P; Dwyer, John; Green, Charlene; Jovic, Gordana; Ritchie, Alastair W S; Russell, J Martin; Sanders, Karen; Thalmann, George; James, Nicholas D

2012-09-15

Systemic Therapy for Advanced or Metastatic Prostate cancer: Evaluation of Drug Efficacy (STAMPEDE) is a randomized controlled trial that follows a novel multi-arm, multi-stage (MAMS) design. We describe methodological and practical issues arising with (1) stopping recruitment to research arms following a pre-planned intermediate analysis and (2) adding a new research arm during the trial. STAMPEDE recruits men who have locally advanced or metastatic prostate cancer who are starting standard long-term hormone therapy. Originally there were five research and one control arms, each undergoing a pilot stage (focus: safety, feasibility), three intermediate 'activity' stages (focus: failure-free survival), and a final 'efficacy' stage (focus: overall survival). Lack-of-sufficient-activity guidelines support the pairwise interim comparisons of each research arm against the control arm; these pre-defined activity cut-off becomes increasingly stringent over the stages. Accrual of further patients continues to the control arm and to those research arms showing activity and an acceptable safety profile. The design facilitates adding new research arms should sufficiently interesting agents emerge. These new arms are compared only to contemporaneously recruited control arm patients using the same intermediate guidelines in a time-delayed manner. The addition of new research arms is subject to adequate recruitment rates to support the overall trial aims. (1) Stopping Existing Therapy: After the second intermediate activity analysis, recruitment was discontinued to two research arms for lack-of-sufficient activity. Detailed preparations meant that changes were implemented swiftly at 100 international centers and recruitment continued seamlessly into Activity Stage III with 3 remaining research arms and the control arm. Further regulatory and ethical approvals were not required because this was already included in the initial trial design.(2) Adding New Therapy: An application to add a new research arm was approved by the funder, (who also organized peer review), industrial partner and regulatory and ethical bodies. This was all done in advance of any decision to stop current therapies. The STAMPEDE experience shows that recruitment to a MAMS trial and mid-flow changes its design are achievable with good planning. This benefits patients and the scientific community as research treatments are evaluated in a more efficient and cost-effective manner. ISRCTN78818544, NCT00268476. First patient into trial: 17 October 2005. First patient into abiraterone comparison: 15 November 2011.

ARM Airborne Carbon Measurements (ARM-ACME) and ARM-ACME 2.5 Final Campaign Reports

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biraud, S. C.; Tom, M. S.; Sweeney, C.

2016-01-01

We report on a 5-year multi-institution and multi-agency airborne study of atmospheric composition and carbon cycling at the Atmospheric Radiation Measurement (ARM) Climate Research Facility’s Southern Great Plains (SGP) site, with scientific objectives that are central to the carbon-cycle and radiative-forcing goals of the U.S. Global Change Research Program and the North American Carbon Program (NACP). The goal of these measurements is to improve understanding of 1) the carbon exchange of the Atmospheric Radiation Measurement (ARM) SGP region; 2) how CO 2 and associated water and energy fluxes influence radiative-forcing, convective processes, and CO 2 concentrations over the ARM SGPmore » region, and 3) how greenhouse gases are transported on continental scales.« less

Anterior prefrontal cortex contributes to action selection through tracking of recent reward trends

PubMed Central

Kovach, Christopher K.; Daw, Nathaniel; Rudrauf, David; Tranel, Daniel; O’Doherty, John P.; Adolphs, Ralph

2012-01-01

The functions of prefrontal cortex remain enigmatic, especially so for its anterior sectors, putatively ranging from planning to self-initiated behavior, social cognition, task-switching and memory. A predominant current theory regarding the most anterior sector, frontopolar cortex (FPC), is that it is involved in exploring alternate courses of action, but the detailed causal mechanisms remain unknown. Here we investigated this issue using the lesion method together with a novel model-based analysis. Eight patients with anterior prefrontal brain lesions including the FPC performed a 4-armed bandit task known from neuroimaging studies to activate FPC. Model-based analyses of learning demonstrated a selective deficit in the ability to extrapolate the most recent trend, despite an intact general ability to learn from past rewards. Whereas both brain-damaged and healthy controls used comparisons between the two most recent choice outcomes to infer trends that influenced their decision about the next choice, the group with anterior prefrontal lesions showed a complete absence of this component and instead based their choice entirely on the cumulative reward history. Given that the FPC is thought to be the most evolutionarily recent expansion of primate prefrontal cortex, we suggest that its function may reflect uniquely human adaptations to select and update models of reward contingency in dynamic environments. PMID:22723683

Ventral striatum lesions do not affect reinforcement learning with deterministic outcomes on slow time scales.

PubMed

Vicario-Feliciano, Raquel; Murray, Elisabeth A; Averbeck, Bruno B

2017-10-01

A large body of work has implicated the ventral striatum (VS) in aspects of reinforcement learning (RL). However, less work has directly examined the effects of lesions in the VS, or other forms of inactivation, on 2-armed bandit RL tasks. We have recently found that lesions in the VS in macaque monkeys affect learning with stochastic schedules but have minimal effects with deterministic schedules. The reasons for this are not currently clear. Because our previous work used short intertrial intervals, one possibility is that the animals were using working memory to bridge stimulus-reward associations from 1 trial to the next. In the present study, we examined learning of 60 pairs of objects, in which the animals received only 1 trial per day with each pair. The large number of object pairs and the long interval (approximately 24 hr) between trials with a given pair minimized the chances that the animals could use working memory to bridge trials. We found that monkeys with VS lesions were unimpaired relative to controls, which suggests that animals with VS lesions can still learn to select rewarded objects even when they cannot make use of working memory. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Bringing Culture to Life through Children's Literature: The Mississippi Delta in the 1930's

ERIC Educational Resources Information Center

Hopper, Peggy F.

2011-01-01

After hearing reminisces from her parents about childhood adventures that took place in the 1930's Mississippi Delta, the author, Peggy F. Hopper, decided to document these stores in two children's books, "Peggy Sue and the Pepper Patch" and "The Adventures of Theodore Roosevelt Hollumway Jones and John Hart: Chasing Bandits."…

New prototype of acousto-optical radio-wave spectrometer with parallel frequency processing for astrophysical applications

NASA Astrophysics Data System (ADS)

Shcherbakov, Alexandre S.; Chavez Dagostino, Miguel; Arellanes, Adan O.; Aguirre Lopez, Arturo

2016-09-01

We develop a multi-band spectrometer with a few spatially parallel optical arms for the combined processing of their data flow. Such multi-band capability has various applications in astrophysical scenarios at different scales: from objects in the distant universe to planetary atmospheres in the Solar system. Each optical arm exhibits original performances to provide parallel multi-band observations with different scales simultaneously. Similar possibility is based on designing each optical arm individually via exploiting different materials for acousto-optical cells operating within various regimes, frequency ranges and light wavelengths from independent light sources. Individual beam shapers provide both the needed incident light polarization and the required apodization to increase the dynamic range of a system. After parallel acousto-optical processing, data flows are united by the joint CCD matrix on the stage of the combined electronic data processing. At the moment, the prototype combines still three bands, i.e. includes three spatial optical arms. The first low-frequency arm operates at the central frequencies 60-80 MHz with frequency bandwidth 40 MHz. The second arm is oriented to middle-frequencies 350-500 MHz with frequency bandwidth 200-300 MHz. The third arm is intended for ultra-high-frequency radio-wave signals about 1.0-1.5 GHz with frequency bandwidth <300 MHz. To-day, this spectrometer has the following preliminary performances. The first arm exhibits frequency resolution 20 KHz; while the second and third arms give the resolution 150-200 KHz. The numbers of resolvable spots are 1500- 2000 depending on the regime of operation. The fourth optical arm at the frequency range 3.5 GHz is currently under construction.

77 FR 61295 - Snapper-Grouper Fishery off the Southern Atlantic States; Snapper-Grouper Management Measures

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-09

...), gutted weight, to ensure that the hook-and-line component of the commercial sector has the opportunity to... hook-and-line quota is not met by September 1, boats with longline endorsements should be able to participate in the hook-and-line component of the commercial sector, using bandit reels, under a 500 lb (227...

System Framework for a Multi-Band, Multi-Mode Software Defined Radio

DTIC Science & Technology

2014-06-01

detection, while the VITA Radio Transport ( VRT ) protocol over Gigabit Ethernet (GIGE) is implemented for the data interface. In addition to the SoC...CTRL VGA CTRL C2 GPP C2 CORE SW ARM0 RX SYN CTRL PL MEMORY MAP DR CTRL GENERIC INTERRUPT CONTROLLER DR GPP VITERBI ALGORITHM & VRT INTERFACE ARM1

Graphic overlays in high-precision teleoperation: Current and future work at JPL

NASA Technical Reports Server (NTRS)

Diner, Daniel B.; Venema, Steven C.

1989-01-01

In space teleoperation additional problems arise, including signal transmission time delays. These can greatly reduce operator performance. Recent advances in graphics open new possibilities for addressing these and other problems. Currently a multi-camera system with normal 3-D TV and video graphics capabilities is being developed. Trained and untrained operators will be tested for high precision performance using two force reflecting hand controllers and a voice recognition system to control two robot arms and up to 5 movable stereo or non-stereo TV cameras. A number of new techniques of integrating TV and video graphics displays to improve operator training and performance in teleoperation and supervised automation are evaluated.

Cyber Adversary Dynamics

DTIC Science & Technology

2013-02-01

that the Government formulated or supplied the drawings, specifications, or other data does not license the holder or any other person or corporation ...preparation. Berk , V. H., Cybenko, G., Souza, I. G. D., & Murphy, J. P. (2012, January). “Managing Malicious Insider Risk through BANDIT.” In System... finances , human resources for example; • Tactics – Short term goals and techniques to achieve those goals; • Strategy – Long term outcomes and

Trends in the application of dynamic allocation methods in multi-arm cancer clinical trials.

PubMed

Pond, Gregory R; Tang, Patricia A; Welch, Stephen A; Chen, Eric X

2010-06-01

Dynamic allocation (DA) methods which attempt to balance baseline prognostic factors between treatment arms, can be used in multi-arm clinical trials to sequentially allocate patients to treatment. Although some experts express concern regarding the validity of inference from trials using DA, others believe DA methods produce more credible results. A review of published multi-arm cancer clinical trials was conducted to explore the frequency of DA use in oncology. Multi-arm phase III clinical trials of at least 100 patients per arm, published in 13 major oncology journals from 1995-2005 were manually reviewed. Information about reported use of DA methods, or randomization via random permuted blocks (PB), was extracted along with trial characteristics. Of 476 published clinical trials, 112 (23.5%) reported using some form of DA method, while 103 (21.6%) reported using PB methods. Most trials (403 or 84.7%) reported stratifying on at least one baseline factor. The mean number of stratification factors was 2.70 per trial, and 78.6% of DA trials reported 3 or more stratification factors compared with 30.2% of non-DA trials (p < 0.001). The frequency of DA use increased over time, with 20.2%, 21.3%, 25.8%, 28.8% and 38.9% of trials reported use in 1995-2001, 2002, 2003, 2004, and 2005, respectively. Use of DA methods was more frequently reported in trials involving an academic co-operative group (28.4% vs. 13.8%), however, no difference was observed between industry-funded and other-funded trials (24.0% vs. 23.2%) or geographical region (19.7% of North American trials, 26.2% of European trials and 21.7% of multinational/other trials). As a retrospective analysis, the true frequency of DA use is likely underreported. Few trials gave complete details of the allocation method used, thus it is possible some manuscripts reported incorrect allocation methods. Journals were selected which were assumed to publish most large, multi-arm clinical trials in cancer from 1995-2005, however, some trials were likely reported in journals other than what was reviewed. DA methods are frequently used in multi-arm cancer clinical trials. The use of DA appears to becoming more common over time and are used more frequently when an academic cooperative group is involved. No relationship between industry funded trials or geographic region and allocation method was observed. Clinical Trials 2010; 7: 227-234. http://ctj.sagepub.com.

Hybrid position/force control of multi-arm cooperating robots

NASA Technical Reports Server (NTRS)

Hayati, Samad

1986-01-01

This paper extends the theory of hybrid position/force control to the case of multi-arm cooperating robots. Cooperation between n robot arms is achieved by controlling each arm such that the burden of actuation is shared between the arms in a nonconflicting way as they control the position of and force on a designated point on an object. The object, which may or may not be in contact with a rigid environment, is assumed to be held rigidly by n robot end-effectors. Natural and artificial position and force constraints are defined for a point on the object and two selection matrices are obtained to control the arms. The position control loops are designed based on each manipulator's Cartesian space dynamic equations. In the position control subspace, a feature is provided which allows the robot arms to exert additional forces/torques to achieve compression, tension, or torsion in the object without affecting the execution of the motion trajectories. In the force control subspace, a method is introduced to minimize the total force/torque magnitude square while realizing the net desired force/torque on the environment.

Contact control for advanced applications of light weight arms

NASA Technical Reports Server (NTRS)

Book, Wayne J.; Kwon, Dong-Soo

1991-01-01

Many applications of robotic and teleoperated manipulator arms require operation in contact and non-contact regimes. This paper deals with both regimes and the transition between them with special attention given to problems of flexibility in the links and drives. This is referred to as contact control. Inverse dynamics is used to plan the tip motion of the flexible link so that the free motion can stop very near the contact surface without collision due to overshoot. Contact must occur at a very low speed since the high frequency impact forces are too sudden to be affected by any feedback generated torques applied to a joint at the other end of the link. The effect of approach velocity and surface properties are discussed. Force tracking is implemented by commands to the deflection states of the link and the contact force. This enables a natural transition between tip position and tip force control that is not possible when the arm is treated as rigid. The effect of feedback gain, force trajectory, and desired final force are of particular interest and are studied. Experimental results are presented on a one link arm and the system performance in the overall contact task is analyzed. Extension to multi-link cases with potential applications are discussed.

Dual-arm manipulators with adaptive control

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1991-01-01

The described and improved multi-arm invention of this application presents three strategies for adaptive control of cooperative multi-arm robots which coordinate control over a common load. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through a load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions; while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are compensated for by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. Circuits in the adaptive feedback and feedforward controllers are varied by novel adaptation laws.

Associations between poor living conditions and multi-morbidity among Syrian migrant agricultural workers in Lebanon

PubMed Central

Mikati, Diana; Hojeij, Safa; El Asmar, Khalil; Chaaya, Monique; Zurayk, Rami

2016-01-01

Background: Syrian migrant farmworkers are among the most marginalized populations in Lebanon, living in poverty, lacking basic legal protections and frequent targets of discrimination. These realities produce living conditions that undermine their basic health and wellbeing. This study explores associations between household living conditions and acute and chronic health problems among Syrian migrant agricultural workers in the Bekaa region of Lebanon. Methods: A survey was carried out in summer of 2011 with a sample of 290 migrant agriculture workers and members of their household living in a migrant farmworker camp. The survey assessed participants living conditions, assets and health conditions. Regression analyses were carried out to examine associations between multi-morbidity and quality of household and neighborhood living conditions. Results: The mean age for the population was 20 years. Forty-seven percent of participants reported health problems. Almost 20% reported either one acute or chronic illness, 15% reported two health problems and 13% reported three or more. The analysis showed a significant positive association between multi-morbidity and poor housing and infrastructure conditions among study participants. Conclusion: The situation for migrant communities in Lebanon has likely further deteriorated since the study was conducted, as hundreds of thousands of new migrants have entered Lebanon since the outbreak of the Syrian armed conflict in 2011. These findings should inspire multi-faceted community development initiatives that provide basic minimums of neighborhood infrastructure and housing quality for Syrian migrant informal settlements across Lebanon, safeguarding the health and wellbeing of community residents. PMID:27402635

Associations between poor living conditions and multi-morbidity among Syrian migrant agricultural workers in Lebanon.

PubMed

Habib, Rima R; Mikati, Diana; Hojeij, Safa; El Asmar, Khalil; Chaaya, Monique; Zurayk, Rami

2016-12-01

Syrian migrant farmworkers are among the most marginalized populations in Lebanon, living in poverty, lacking basic legal protections and frequent targets of discrimination. These realities produce living conditions that undermine their basic health and wellbeing. This study explores associations between household living conditions and acute and chronic health problems among Syrian migrant agricultural workers in the Bekaa region of Lebanon. A survey was carried out in summer of 2011 with a sample of 290 migrant agriculture workers and members of their household living in a migrant farmworker camp. The survey assessed participants living conditions, assets and health conditions. Regression analyses were carried out to examine associations between multi-morbidity and quality of household and neighborhood living conditions. The mean age for the population was 20 years. Forty-seven percent of participants reported health problems. Almost 20% reported either one acute or chronic illness, 15% reported two health problems and 13% reported three or more. The analysis showed a significant positive association between multi-morbidity and poor housing and infrastructure conditions among study participants. The situation for migrant communities in Lebanon has likely further deteriorated since the study was conducted, as hundreds of thousands of new migrants have entered Lebanon since the outbreak of the Syrian armed conflict in 2011. These findings should inspire multi-faceted community development initiatives that provide basic minimums of neighborhood infrastructure and housing quality for Syrian migrant informal settlements across Lebanon, safeguarding the health and wellbeing of community residents. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association.

Optical depth measurements by shadow-band radiometers and their uncertainties.

PubMed

Alexandrov, Mikhail D; Kiedron, Peter; Michalsky, Joseph J; Hodges, Gary; Flynn, Connor J; Lacis, Andrew A

2007-11-20

Shadow-band radiometers in general, and especially the Multi-Filter Rotating Shadow-band Radiometer (MFRSR), are widely used for atmospheric optical depth measurements. The major programs running MFRSR networks in the United States include the Department of Energy Atmospheric Radiation Measurement (ARM) Program, U.S. Department of Agriculture UV-B Monitoring and Research Program, National Oceanic and Atmospheric Administration Surface Radiation (SURFRAD) Network, and NASA Solar Irradiance Research Network (SIRN). We discuss a number of technical issues specific to shadow-band radiometers and their impact on the optical depth measurements. These problems include instrument tilt and misalignment, as well as some data processing artifacts. Techniques for data evaluation and automatic detection of some of these problems are described.

Column and Near-surface Aerosol Properties during TCAP: Temporal Changes in a Coastal Region

NASA Astrophysics Data System (ADS)

Kassianov, E.; Barnard, J.; Pekour, M. S.; Berg, L. K.; Shilling, J. E.; Fast, J. D.; Michalsky, J. J.; Lantz, K. O.; Hodges, G.

2013-12-01

An important problem facing climate-related studies is to separate the impacts of naturally occurring and anthropogenic aerosol. This problem is even more challenging in coastal regions located downwind of large metropolitan areas. Cape Cod situated on the easternmost portion of Massachusetts (along the east coast of the United States) is an example of one of these regions. The Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/) was designed to study the evolution of optical, microphysical and chemical properties of both marine aerosol and aerosol transported from North America to the Atlantic as well as their impact on the radiation energy budget. The TCAP has been recently conducted (2012-2013) on Cape Cod with support from the U.S. Department of Energy's (DOE's) Atmospheric Radiation Measurement (ARM) Program (http://www.arm.gov/). During the TCAP, the ground-based ARM Mobile Facility (AMF) was deployed on Cape Cod. The AMF site (at 41.87°N; 70.28°W) was equipped with numerous instruments for sampling aerosol, cloud and radiative properties, including a Multi-Filter Rotating Shadowband Radiometer (MFRSR), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS), a three-wavelength nephelometer, and suite of instruments to measure the aerosol chemical composition. In this study we present an analysis of diurnal and day-to-day variability of the column and near-surface aerosol properties obtained from remote sensing (MFRSR data) and in situ measurements (SMPS, APS, nephelometer, chemical composition), respectively. The importance of this variability to direct aerosol radiative forcing at different time scales and its relation to the long-range transport will be discussed. Some regional model results will also be presented.

TEM verification of the <111>-type 4-arm multi-junction in [001]-Mo single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsiung, L

2005-03-14

To investigate and verify the formation of <111>-type 4-arm multi-junction by the dislocation reaction of 1/2[111] [b1] + 1/2[{bar 1}1{bar 1}] [b2] + 1/2[{bar 1}{bar 1}1] [b3] = 1/2[{bar 1}11] [b4], which has recently been discovered through computer simulations conducted by Vasily Bulatov and his colleagues.

JPRS Report, Africa, (Sub-Sahara).

DTIC Science & Technology

1987-08-31

buffer stock has curbed the escalation in prices. A slight increase in national production and an influx of gifts from nations or international...Moxico Province Commissioner on Military Situation (JORNAL DE ANGOLA, 1 Jul 87) 18 ’Bandits’ Attack Export Production Unit (JORNAL DE ANGOLA, 14...will continue or even be intensified, regardless of whether the organs of authority or other states are pleased." The RENAMO views the presence of

Dual-Arm Generalized Compliant Motion With Shared Control

NASA Technical Reports Server (NTRS)

Backes, Paul G.

1994-01-01

Dual-Arm Generalized Compliant Motion (DAGCM) primitive computer program implementing improved unified control scheme for two manipulator arms cooperating in task in which both grasp same object. Provides capabilities for autonomous, teleoperation, and shared control of two robot arms. Unifies cooperative dual-arm control with multi-sensor-based task control and makes complete task-control capability available to higher-level task-planning computer system via large set of input parameters used to describe desired force and position trajectories followed by manipulator arms. Some concepts discussed in "A Generalized-Compliant-Motion Primitive" (NPO-18134).

Multi-enzyme complexes on DNA scaffolds capable of substrate channelling with an artificial swinging arm

NASA Astrophysics Data System (ADS)

Fu, Jinglin; Yang, Yuhe Renee; Johnson-Buck, Alexander; Liu, Minghui; Liu, Yan; Walter, Nils G.; Woodbury, Neal W.; Yan, Hao

2014-07-01

Swinging arms are a key functional component of multistep catalytic transformations in many naturally occurring multi-enzyme complexes. This arm is typically a prosthetic chemical group that is covalently attached to the enzyme complex via a flexible linker, allowing the direct transfer of substrate molecules between multiple active sites within the complex. Mimicking this method of substrate channelling outside the cellular environment requires precise control over the spatial parameters of the individual components within the assembled complex. DNA nanostructures can be used to organize functional molecules with nanoscale precision and can also provide nanomechanical control. Until now, protein-DNA assemblies have been used to organize cascades of enzymatic reactions by controlling the relative distance and orientation of enzymatic components or by facilitating the interface between enzymes/cofactors and electrode surfaces. Here, we show that a DNA nanostructure can be used to create a multi-enzyme complex in which an artificial swinging arm facilitates hydride transfer between two coupled dehydrogenases. By exploiting the programmability of DNA nanostructures, key parameters including position, stoichiometry and inter-enzyme distance can be manipulated for optimal activity.

Multi-enzyme complexes on DNA scaffolds capable of substrate channelling with an artificial swinging arm.

PubMed

Fu, Jinglin; Yang, Yuhe Renee; Johnson-Buck, Alexander; Liu, Minghui; Liu, Yan; Walter, Nils G; Woodbury, Neal W; Yan, Hao

2014-07-01

Swinging arms are a key functional component of multistep catalytic transformations in many naturally occurring multi-enzyme complexes. This arm is typically a prosthetic chemical group that is covalently attached to the enzyme complex via a flexible linker, allowing the direct transfer of substrate molecules between multiple active sites within the complex. Mimicking this method of substrate channelling outside the cellular environment requires precise control over the spatial parameters of the individual components within the assembled complex. DNA nanostructures can be used to organize functional molecules with nanoscale precision and can also provide nanomechanical control. Until now, protein-DNA assemblies have been used to organize cascades of enzymatic reactions by controlling the relative distance and orientation of enzymatic components or by facilitating the interface between enzymes/cofactors and electrode surfaces. Here, we show that a DNA nanostructure can be used to create a multi-enzyme complex in which an artificial swinging arm facilitates hydride transfer between two coupled dehydrogenases. By exploiting the programmability of DNA nanostructures, key parameters including position, stoichiometry and inter-enzyme distance can be manipulated for optimal activity.

Method and apparatus for adaptive force and position control of manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1995-01-01

The described and improved multi-arm invention of this application presents three strategies for adaptive control of cooperative multi-arm robots which coordinate control over a common load. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through a load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions; while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are compensated for by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. Circuits in the adaptive feedback and feedforward controllers are varied by novel adaptation laws.

A manipulative instrument with simultaneous gesture and end-effector trajectory planning and controlling

NASA Astrophysics Data System (ADS)

Lin, Hsien-I.; Nguyen, Xuan-Anh

2017-05-01

To operate a redundant manipulator to accomplish the end-effector trajectory planning and simultaneously control its gesture in online programming, incorporating the human motion is a useful and flexible option. This paper focuses on a manipulative instrument that can simultaneously control its arm gesture and end-effector trajectory via human teleoperation. The instrument can be classified by two parts; first, for the human motion capture and data processing, marker systems are proposed to capture human gesture. Second, the manipulator kinematics control is implemented by an augmented multi-tasking method, and forward and backward reaching inverse kinematics, respectively. Especially, the local-solution and divergence problems of a multi-tasking method are resolved by the proposed augmented multi-tasking method. Computer simulations and experiments with a 7-DOF (degree of freedom) redundant manipulator were used to validate the proposed method. Comparison among the single-tasking, original multi-tasking, and augmented multi-tasking algorithms were performed and the result showed that the proposed augmented method had a good end-effector position accuracy and the most similar gesture to the human gesture. Additionally, the experimental results showed that the proposed instrument was realized online.

Practice-driven evaluation of a multi-layered psychosocial care package for children in areas of armed conflict.

PubMed

Jordans, M J D; Komproe, I H; Tol, W A; Susanty, D; Vallipuram, A; Ntamatumba, P; Lasuba, A C; De Jong, J T V M

2011-06-01

Psychosocial and mental health service delivery frameworks for children in low-income countries are scarce. This paper presents a practice-driven evaluation of a multi-layered community-based care package in Burundi, Indonesia, Sri Lanka and Sudan, through a set of indicators; (a) perceived treatment gains; (b) treatment satisfaction; (c) therapist burden; (d) access to care; (e) care package costs. Across four settings (n = 29,292 children), beneficiaries reported high levels of client satisfaction and moderate post-treatment problem reductions. Service providers reported significant levels of distress related to service delivery. Cost analyses demonstrated mean cost per service user to vary from 3.46 to 17.32 depending on country and specification of costs. The results suggest a multi-layered psychosocial care package appears feasible and satisfactory in reaching out to substantial populations of distressed children through different levels of care. Future replication should address therapist burden, cost reductions to increase sustainability and increase evidence for treatment efficacy.

Using shape to turn off blinking for two-colour multiexciton emission in CdSe/CdS tetrapods

NASA Astrophysics Data System (ADS)

Mishra, Nimai; Orfield, Noah J.; Wang, Feng; Hu, Zhongjian; Krishnamurthy, Sachidananda; Malko, Anton V.; Casson, Joanna L.; Htoon, Han; Sykora, Milan; Hollingsworth, Jennifer A.

2017-05-01

Semiconductor nanostructures capable of emitting from two excited states and thereby of producing two photoluminescence colours are of fundamental and potential technological significance. In this limited class of nanocrystals, CdSe/CdS core/arm tetrapods exhibit the unusual trait of two-colour (red and green) multiexcitonic emission, with green emission from the CdS arms emerging only at high excitation fluences. Here we show that by synthetic shape-tuning, both this multi-colour emission process, and blinking and photobleaching behaviours of single tetrapods can be controlled. Specifically, we find that the properties of dual emission and single-nanostructure photostability depend on different structural parameters--arm length and arm diameter, respectively--but that both properties can be realized in the same nanostructure. Furthermore, based on results of correlated photoluminescence and transient absorption measurements, we conclude that hole-trap filling in the arms and partial state-filling in the core are necessary preconditions for the observation of multiexciton multi-colour emission.

Using shape to turn off blinking for two-colour multiexciton emission in CdSe/CdS tetrapods

PubMed Central

Mishra, Nimai; Orfield, Noah J.; Wang, Feng; Hu, Zhongjian; Krishnamurthy, Sachidananda; Malko, Anton V.; Casson, Joanna L.; Htoon, Han; Sykora, Milan; Hollingsworth, Jennifer A.

2017-01-01

Semiconductor nanostructures capable of emitting from two excited states and thereby of producing two photoluminescence colours are of fundamental and potential technological significance. In this limited class of nanocrystals, CdSe/CdS core/arm tetrapods exhibit the unusual trait of two-colour (red and green) multiexcitonic emission, with green emission from the CdS arms emerging only at high excitation fluences. Here we show that by synthetic shape-tuning, both this multi-colour emission process, and blinking and photobleaching behaviours of single tetrapods can be controlled. Specifically, we find that the properties of dual emission and single-nanostructure photostability depend on different structural parameters—arm length and arm diameter, respectively—but that both properties can be realized in the same nanostructure. Furthermore, based on results of correlated photoluminescence and transient absorption measurements, we conclude that hole-trap filling in the arms and partial state-filling in the core are necessary preconditions for the observation of multiexciton multi-colour emission. PMID:28497776

Controlled synthesis of multi-arm star polyether-polycarbonate polyols based on propylene oxide and CO2.

PubMed

Hilf, Jeannette; Schulze, Patricia; Seiwert, Jan; Frey, Holger

2014-01-01

Multi-arm star copolymers based on a hyperbranched poly(propylene oxide) polyether-polyol (hbPPO) as a core and poly(propylene carbonate) (PPC) arms are synthesized in two steps from propylene oxide (PO), a small amount of glycidol and CO2 . The PPC arms are prepared via carbon dioxide (CO2 )/PO copolymerization, using hbPPO as a multifunctional macroinitiator and the (R,R)-(salcy)CoOBzF5 catalyst. Star copolymers with 14 and 28 PPC arms, respectively, and controlled molecular weights in the range of 2700-8800 g mol(-1) are prepared (Mw /Mn = 1.23-1.61). Thermal analysis reveals lowered glass transition temperatures in the range of -8 to 10 °C for the PPC star polymers compared with linear PPC, which is due to the influence of the flexible polyether core. Successful conversion of the terminal hydroxyl groups with phenylisocyanate demonstrates the potential of the polycarbonate polyols for polyurethane synthesis. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Arm CT scan

MedlinePlus

CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... Healing problems or scar tissue following surgery A CT scan may also be used to guide a surgeon ...

Industrial dual arm robot manipulator for precise assembly of mechanical parts

NASA Astrophysics Data System (ADS)

Park, Chanhun; Kim, Doohyung; Park, Kyoungtaik; Choi, Youngjin

2007-12-01

A new structure of dual arm robot manipulator which consists of two industrial 6-DOF arms and one 2-DOF Torso is introduced. Each industrial 6-DOF arm is able to be used as a stand-alone industrial 6-DOF robot manipulator and as a part of dual arm manipulator at the same time. These structures help the robot maker which is willing to succeed in the emerging dual arm robot market in order to have high competition for the current industrial robot market at same time. Self-collision detection algorithm for multi-arm robot and kinematics algorithms for the developed dual arm robot manipulator which are implemented in our controller are introduced.

Multi-Filter Rotating Shadowband Radiometers Mentor Report and Baseline Surface Radiation Network Submission Status

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodges, G.

2005-03-18

There are currently twenty-four Multi-Filter Rotating Shadowband Radiometers (MFRSR) operating within Atmospheric Radiation Measurement (ARM). Eighteen are located within the Southern Great Plains (SGP) region, there is one at each of the North Slope of Alaska (NSA) and Tropical Western Pacific (TWP) sites, and one is part of the instrumentation of the ARM Mobile Facility. At this time there are four sites, all extended facilities within the SGP, that are equipped for a MFRSR but do not have one due to instrument failure and a lack of spare instruments. In addition to the MFRSRs, there are three other MFRSR derivedmore » instruments that ARM operates. They are the Multi-Filter Radiometer (MFR), the Normal Incidence Multi-Filter Radiometer (NIMFR) and the Narrow Field of View (NFOV) radiometer. All are essentially just the head of a MFRSR used in innovative ways. The MFR is mounted on a tower and pointed at the surface. At the SGP Central Facility there is one at ten meters and one at twenty-five meters. The NSA has a MFR at each station, both at the ten meter level. ARM operates three NIMFRs; one is at the SGP Central Facility and one at each of the NSA stations. There are two NFOVs, both at the SGP Central Facility. One is a single channel (870) and the other utilizes two channels (673 and 870).« less

The STAMPEDE trial: paradigm-changing data through innovative trial design.

PubMed

Carthon, Bradley C; Antonarakis, Emmanuel S

2016-09-01

Despite the numerous regulatory approvals for prostate cancer, metastatic prostate cancer remains a huge burden for men worldwide. In an exciting development, James et al . recently published data from the Systemic Therapy in Advanced or Metastatic Prostate Cancer: Evaluation of Drug Efficacy: a multi-stage multi-arm randomised control trial (STAMPEDE). This is an innovative multi-arm multi-stage (MAMS) trial that has utilized one control arm and several comparator arms in order to provide evidence for the inclusion of therapies beyond standard androgen deprivation alone. The patient population included: (I) men with high-risk, non-metastatic, node-negative disease; (II) men with distant-metastatic or node-positive disease; and (III) men with previously-treated prostate cancer by prostatectomy or definitive radiotherapy presenting with relapse. Men were to continue androgen deprivation for at least 2 years. The current data published by this group supports earlier results and provides additional evidence that docetaxel utilized in an up-front fashion provides a survival benefit in men with hormone-sensitive metastatic prostate cancer. Moreover, the initial results from STAMPEDE show how therapies without a demonstrated survival benefit can be efficiently excluded from further study once the likelihood of a benefit is ruled out by a predetermined analysis. In this piece, we will review the STAMPEDE data, contrast it with existing results, and provide our perspectives on how this will affect future trial conduct in the field of prostate cancer.

Developing a multi-joint upper limb exoskeleton robot for diagnosis, therapy, and outcome evaluation in neurorehabilitation.

PubMed

Ren, Yupeng; Kang, Sang Hoon; Park, Hyung-Soon; Wu, Yi-Ning; Zhang, Li-Qun

2013-05-01

Arm impairments in patients post stroke involve the shoulder, elbow and wrist simultaneously. It is not very clear how patients develop spasticity and reduced range of motion (ROM) at the multiple joints and the abnormal couplings among the multiple joints and the multiple degrees-of-freedom (DOF) during passive movement. It is also not clear how they lose independent control of individual joints/DOFs and coordination among the joints/DOFs during voluntary movement. An upper limb exoskeleton robot, the IntelliArm, which can control the shoulder, elbow, and wrist, was developed, aiming to support clinicians and patients with the following integrated capabilities: 1) quantitative, objective, and comprehensive multi-joint neuromechanical pre-evaluation capabilities aiding multi-joint/DOF diagnosis for individual patients; 2) strenuous and safe passive stretching of hypertonic/deformed arm for loosening up muscles/joints based on the robot-aided diagnosis; 3) (assistive/resistive) active reaching training after passive stretching for regaining/improving motor control ability; and 4) quantitative, objective, and comprehensive neuromechanical outcome evaluation at the level of individual joints/DOFs, multiple joints, and whole arm. Feasibility of the integrated capabilities was demonstrated through experiments with stroke survivors and healthy subjects.

Gerst working on JEM airlock satellite deployer

NASA Image and Video Library

2014-06-25

ISS040-E-019318 (25 June 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, prepares to transfer a multi-purpose experiment platform and a robotic arm known as the Small Fine Arm through the Kibo module?s scientific airlock. The Small Fine Arm, which attaches to the Kibo?s larger main arm, handles delicate operations involved in exchanging experiments and payloads located on the Exposed Facility.

Gerst working on JEM airlock satellite deployer

NASA Image and Video Library

2014-06-25

ISS040-E-019300 (25 June 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, prepares to transfer a multi-purpose experiment platform and a robotic arm known as the Small Fine Arm through the Kibo module?s scientific airlock. The Small Fine Arm, which attaches to the Kibo?s larger main arm, handles delicate operations involved in exchanging experiments and payloads located on the Exposed Facility.

Gerst working on JEM airlock satellite deployer

NASA Image and Video Library

2014-06-25

ISS040-E-019312 (25 June 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, prepares to transfer a multi-purpose experiment platform and a robotic arm known as the Small Fine Arm through the Kibo module?s scientific airlock. The Small Fine Arm, which attaches to the Kibo?s larger main arm, handles delicate operations involved in exchanging experiments and payloads located on the Exposed Facility.

Gerst working on JEM airlock satellite deployer

NASA Image and Video Library

2014-06-25

ISS040-E-019307 (25 June 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, prepares to transfer a multi-purpose experiment platform and a robotic arm known as the Small Fine Arm through the Kibo module?s scientific airlock. The Small Fine Arm, which attaches to the Kibo?s larger main arm, handles delicate operations involved in exchanging experiments and payloads located on the Exposed Facility.

Gerst working on JEM airlock satellite deployer

NASA Image and Video Library

2014-06-25

ISS040-E-019299 (25 June 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, prepares to transfer a multi-purpose experiment platform and a robotic arm known as the Small Fine Arm through the Kibo module?s scientific airlock. The Small Fine Arm, which attaches to the Kibo?s larger main arm, handles delicate operations involved in exchanging experiments and payloads located on the Exposed Facility.

Multi-arm spectrometer for parallel frequency analysis of radio-wave signals oriented to astronomical observations

NASA Astrophysics Data System (ADS)

Shcherbakov, Alexandre S.; Chavez Dagostino, Miguel; Arellanes, Adan Omar; Tepichin Rodriguez, Eduardo

2017-08-01

We describe a potential prototype of modern spectrometer based on acousto-optical technique with three parallel optical arms for analysis of radio-wave signals specific to astronomical observations. Each optical arm exhibits original performances to provide parallel multi-band observations with different scales simultaneously. Similar multi-band instrument is able to realize measurements within various scenarios from planetary atmospheres to attractive objects in the distant Universe. The arrangement under development has two novelties. First, each optical arm represents an individual spectrum analyzer with its individual performances. Such an approach is conditioned by exploiting various materials for acousto-optical cells operating within various regimes, frequency ranges, and light wavelengths from independent light sources. Individually produced beam shapers give both the needed incident light polarization and the required apodization for light beam to increase the dynamic range of the system as a whole. After parallel acousto-optical processing, a few data flows from these optical arms are united by the joint CCD matrix on the stage of the combined extremely high-bit rate electronic data processing that provides the system performances as well. The other novelty consists in the usage of various materials for designing wide-aperture acousto-optical cells exhibiting the best performances within each of optical arms. Here, one can mention specifically selected cuts of tellurium dioxide, bastron, and lithium niobate, which overlap selected areas within the frequency range from 40 MHz to 2.0 GHz. Thus one yields the united versatile instrument for comprehensive studies of astronomical objects simultaneously with precise synchronization in various frequency ranges.

Mode Theory of Multi-Armed Spiral Antennas and Its Application to Electronic Warfare Antennas

NASA Astrophysics Data System (ADS)

Radway, Matthew J.

Since their invention about 55 years ago, spiral antennas have earned a reputation for providing stable impedance and far-field patterns over multi-decade frequency ranges. For the first few decades these antennas were researched for electronic warfare receiving applications, primarily in the 2-18 GHz range. This research was often done under conditions of secrecy, and often by private contractors who did not readily share their research, and now have been defunct for decades. Even so, the body of literature on the two-armed variant of these antennas is rich, often leading non-specialists to the misconception that these antennas are completely understood. Furthermore, early work was highly experimental in nature, and was conducted before modern data collection and postprocessing capabilities were widespread, which limited the range of the studies. Recent research efforts have focused on extending the application of spirals into new areas, as well as applying exotic materials to `improve' their performance and reduce their size. While interesting results have been obtained, in most instances these were incomplete, often compromising the frequency independent nature of these antennas. This thesis expands the role of the multi-armed spiral outside of its traditional niche of receive-only monopulse direction finding. As a first step, careful study of the spiral-antenna mode theory is undertaken with particular attention paid to the concepts of mode filtering and modal decomposition. A technique for reducing the modal impedance of high arm-count spirals is introduced. The insights gained through this theoretical study are first used to improve the far-field performance of the coiled-arm spiral antenna. Specifically, expanding the number of arms on a coiled arm spiral from two to four while providing proper excitation enables dramatically improved broadside axial ratio and azimuthal pattern uniformity. The multiarming technique is then applied to the design of an antenna with exceptionally stable and clean radiation patterns without use of an absorbing cavity. The multiarming technique allows the spiral to retain its pattern integrity at frequencies well below those of comparable two-armed spiral antennas. A quadrifilar helix-type of end-loading is applied to the end of the spiral, resulting in dramatically-improved low-frequency gain. Careful application of resistive end-loading allows good impedance matching at frequencies as low as one-half of the Mode 1 cutoff frequency, while providing acceptable radiation efficiency due to effective use of the available antenna volume. A novel dual-layering technique for reducing the spiral's modal impedance is presented, allowing the antenna to present a good impedance match to a 50 ohm system. The third application of mode theory has been to exploit the wideband multi-mode capability of the multi-armed spiral antenna to implement a simple wide-band radiation pattern nulling technique on a multi-armed spiral antenna. It is shown that wideband nulling is possible and that, in contrast to traditional array antennas, grating lobes do not appear even over extremely wide bandwidths. Simple techniques for addressing the phenomenon of null rotation with frequency are discussed. Finally, mode theory has been used to analyze beamformer non-idealities. This has led to the revelation that the spectral distribution of beamformer errors is at least as important as the magnitude of those errors. Proper choice of beamformer topology can result in noticeable improvement in the antenna performance.

Multi-organ dysfunction in bodybuilding possibly caused by prolonged hypercalcemia due to multi-substance abuse: case report and review of literature.

PubMed

Schäfer, C N; Guldager, H; Jørgensen, H L

2011-01-01

A 26-year-old male bodybuilder was admitted to the surgical department of a Danish community hospital for hematemesis. During the clinical interview, he revealed that he had recently finished a course of anabolic steroids and erythropoietin. The patient also had a previous history of infections and chronic ulcers due to paraffin-oil injections in both upper arms one year before. Over the course of the next few hours, the patient developed signs of multi-organ dysfunction, including pancreatitis, hemorrhagic gastritis, nephropathy with temporary anuria, and respiratory insufficiency, and was transferred to the ICU. After manometric monitoring on the patient's upper arms proved difficult, invasive blood pressure monitoring was used and revealed that the patient was in a state of hypertensive crisis. This case of multi-organ dysfunction was possibly caused by multi-substance-induced hypercalcemia. © Georg Thieme Verlag KG Stuttgart · New York.

The globus pallidus pars interna in goal-oriented and routine behaviors: Resolving a long-standing paradox.

PubMed

Piron, Camille; Kase, Daisuke; Topalidou, Meropi; Goillandeau, Michel; Orignac, Hugues; N'Guyen, Tho-Haï; Rougier, Nicolas; Boraud, Thomas

2016-08-01

There is an apparent contradiction between experimental data showing that the basal ganglia are involved in goal-oriented and routine behaviors and clinical observations. Lesion or disruption by deep brain stimulation of the globus pallidus interna has been used for various therapeutic purposes ranging from the improvement of dystonia to the treatment of Tourette's syndrome. None of these approaches has reported any severe impairment in goal-oriented or automatic movement. To solve this conundrum, we trained 2 monkeys to perform a variant of a 2-armed bandit-task (with different reward contingencies). In the latter we alternated blocks of trials with choices between familiar rewarded targets that elicit routine behavior and blocks with novel pairs of targets that require an intentional learning process. Bilateral inactivation of the globus pallidus interna, by injection of muscimol, prevents animals from learning new contingencies while performance remains intact, although slower for the familiar stimuli. We replicate in silico these data by adding lateral competition and Hebbian learning in the cortical layer of the theoretical model of the cortex-basal ganglia loop that provided the framework of our experimental approach. The basal ganglia play a critical role in the deliberative process that underlies learning but are not necessary for the expression of routine movements. Our approach predicts that after pallidotomy or during stimulation, patients should have difficulty with complex decision-making processes or learning new goal-oriented behaviors. © 2016 Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

Altered neural encoding of prediction errors in assault-related posttraumatic stress disorder.

PubMed

Ross, Marisa C; Lenow, Jennifer K; Kilts, Clinton D; Cisler, Josh M

2018-05-12

Posttraumatic stress disorder (PTSD) is widely associated with deficits in extinguishing learned fear responses, which relies on mechanisms of reinforcement learning (e.g., updating expectations based on prediction errors). However, the degree to which PTSD is associated with impairments in general reinforcement learning (i.e., outside of the context of fear stimuli) remains poorly understood. Here, we investigate brain and behavioral differences in general reinforcement learning between adult women with and without a current diagnosis of PTSD. 29 adult females (15 PTSD with exposure to assaultive violence, 14 controls) underwent a neutral reinforcement-learning task (i.e., two arm bandit task) during fMRI. We modeled participant behavior using different adaptations of the Rescorla-Wagner (RW) model and used Independent Component Analysis to identify timecourses for large-scale a priori brain networks. We found that an anticorrelated and risk sensitive RW model best fit participant behavior, with no differences in computational parameters between groups. Women in the PTSD group demonstrated significantly less neural encoding of prediction errors in both a ventral striatum/mPFC and anterior insula network compared to healthy controls. Weakened encoding of prediction errors in the ventral striatum/mPFC and anterior insula during a general reinforcement learning task, outside of the context of fear stimuli, suggests the possibility of a broader conceptualization of learning differences in PTSD than currently proposed in current neurocircuitry models of PTSD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Collected Works of Mao Tse-Tung (1917-1949). Volumes 7-10

DTIC Science & Technology

1978-11-16

Take Note Who Is the True Ruler of Our Country Today (18 May 1941) 58 Yenan Commentator on Current Affairs (24 May 1941) 63 Rumor and...resistance war and save the nation and the significance of initiating the political life of the nation toward true democracy. Therefore, besides continuing...especially to prepare for a true counteroffensive when the conditions are favorable and to expel the enemy bandits, a new national defense army must

Selecting promising treatments in randomized Phase II cancer trials with an active control.

PubMed

Cheung, Ying Kuen

2009-01-01

The primary objective of Phase II cancer trials is to evaluate the potential efficacy of a new regimen in terms of its antitumor activity in a given type of cancer. Due to advances in oncology therapeutics and heterogeneity in the patient population, such evaluation can be interpreted objectively only in the presence of a prospective control group of an active standard treatment. This paper deals with the design problem of Phase II selection trials in which several experimental regimens are compared to an active control, with an objective to identify an experimental arm that is more effective than the control or to declare futility if no such treatment exists. Conducting a multi-arm randomized selection trial is a useful strategy to prioritize experimental treatments for further testing when many candidates are available, but the sample size required in such a trial with an active control could raise feasibility concerns. In this study, we extend the sequential probability ratio test for normal observations to the multi-arm selection setting. The proposed methods, allowing frequent interim monitoring, offer high likelihood of early trial termination, and as such enhance enrollment feasibility. The termination and selection criteria have closed form solutions and are easy to compute with respect to any given set of error constraints. The proposed methods are applied to design a selection trial in which combinations of sorafenib and erlotinib are compared to a control group in patients with non-small-cell lung cancer using a continuous endpoint of change in tumor size. The operating characteristics of the proposed methods are compared to that of a single-stage design via simulations: The sample size requirement is reduced substantially and is feasible at an early stage of drug development.

Prevalence and risk factors associated with pain 21 months following surgery for breast cancer.

PubMed

Moloney, Niamh; Sung, Jennie Man Wai; Kilbreath, Sharon; Dylke, Elizabeth

2016-11-01

This study investigated (1) the prevalence of pain following breast cancer treatment including moderate-to-severe persistent pain and (2) the association of risk factors, present 1 month following surgery, with pain at 21 months following surgery. This information may aid the development of clinical guidelines for early pain assessment and intervention in this population. This study was a retrospective analysis of core and breast modules of the European Organisation for Research and Treatment of Cancer (EORTC) questionnaire from 121 participants with early breast cancer. The relationships between potential risk factors (subscales derived from the EORTC), measured within 1 month following surgery, and pain at 21 months following surgery were analysed using univariable and multi-variable logistic regression. At 21 months following surgery, 46.3 % of participants reported pain, with 24 % categorised as having moderate or severe pain. Prevalence of pain was similar between those who underwent axillary lymph node dissection versus biopsy. Univariate logistic regression identified baseline pain (odds ratio (95 % CI): 2.7 (1.1 to 6.4)); baseline arm symptoms (11.2 (1.4 to 89.8)); emotional function (0.4 (0.1 to 0.8)) and insomnia (2.3 (1.1 to 4.7) as significantly associated with pain at 21 months. In multi-variable analysis, two factors were independently associated with pain at 21 months-baseline arm symptoms and emotional subscale scores. Pain is a significant problem following breast cancer treatment in both the early post-operative period and months following surgery. Risk factors for pain at long-term follow-up included arm symptoms and higher emotional subscale scores at baseline.

CRUX: A compliant robotic upper-extremity exosuit for lightweight, portable, multi-joint muscular augmentation.

PubMed

Lessard, Steven; Pansodtee, Pattawong; Robbins, Ash; Baltaxe-Admony, Leya Breanna; Trombadore, James M; Teodorescu, Mircea; Agogino, Adrian; Kurniawan, Sri

2017-07-01

Wearable robots can potentially offer their users enhanced stability and strength. These augmentations are ideally designed to actuate harmoniously with the user's movements and provide extra force as needed. The creation of such robots, however, is particularly challenging due to the underlying complexity of the human body. In this paper, we present a compliant, robotic exosuit for upper extremities called CRUX. This exosuit, inspired by tensegrity models of the human arm, features a lightweight (1.3 kg), flexible multi-joint design for portable augmentation. We also illustrate how CRUX maintains the full range of motion of the upper-extremities for its users while providing multi-DoF strength amplification to the major muscles of the arm, as evident by tracking the heart rate of an individual exercising said arm. Exosuits such as CRUX may be useful in physical therapy and in extreme environments where users are expected to exert their bodies to the fullest extent.

Multi-muscle FES force control of the human arm for arbitrary goals.

PubMed

Schearer, Eric M; Liao, Yu-Wei; Perreault, Eric J; Tresch, Matthew C; Memberg, William D; Kirsch, Robert F; Lynch, Kevin M

2014-05-01

We present a method for controlling a neuroprosthesis for a paralyzed human arm using functional electrical stimulation (FES) and characterize the errors of the controller. The subject has surgically implanted electrodes for stimulating muscles in her shoulder and arm. Using input/output data, a model mapping muscle stimulations to isometric endpoint forces measured at the subject's hand was identified. We inverted the model of this redundant and coupled multiple-input multiple-output system by minimizing muscle activations and used this inverse for feedforward control. The magnitude of the total root mean square error over a grid in the volume of achievable isometric endpoint force targets was 11% of the total range of achievable forces. Major sources of error were random error due to trial-to-trial variability and model bias due to nonstationary system properties. Because the muscles working collectively are the actuators of the skeletal system, the quantification of errors in force control guides designs of motion controllers for multi-joint, multi-muscle FES systems that can achieve arbitrary goals.

Control of free-flying space robot manipulator systems

NASA Technical Reports Server (NTRS)

Cannon, Robert H., Jr.

1977-01-01

To accelerate the development of multi-armed, free-flying satellite manipulators, a fixed-base cooperative manipulation facility is being developed. The work performed on multiple arm cooperation on a free-flying robot is summarized. Research is also summarized on global navigation and control of free-flying space robots. The Locomotion Enhancement via Arm Pushoff (LEAP) approach is described and progress to date is presented.

Method and apparatus for hybrid position/force control of multi-arm cooperating robots

NASA Technical Reports Server (NTRS)

Hayati, Samad A. (Inventor)

1989-01-01

Two or more robotic arms having end effectors rigidly attached to an object to be moved are disclosed. A hybrid position/force control system is provided for driving each of the robotic arms. The object to be moved is represented as having a total mass that consists of the actual mass of the object to be moved plus the mass of the moveable arms that are rigidly attached to the moveable object. The arms are driven in a positive way by the hybrid control system to assure that each arm shares in the position/force applied to the object. The burden of actuation is shared by each arm in a non-conflicting way as the arm independently control the position of, and force upon, a designated point on the object.

Bandit: Technologies for Proximity Operations of Teams of Sub-10Kg Spacecraft

DTIC Science & Technology

2007-10-16

and adding a dedicated overhead camera system. As will be explained below, the forced-air system did not work and the existing system has proven too...erratic to justify the expense of the camera system. 6DOF Software Simulator. The existing Java-based graphical 6DOF simulator was to be improved for...proposed camera system for a nonfunctional table. The C-9 final report is enclosed. ["Prf flj ,er Figure 1. Forced-air table schematic Figure 2

Design and Implementation of Pointer-Type Multi Meters Intelligent Recognition Device Based on ARM Platform

NASA Astrophysics Data System (ADS)

Cui, Yang; Luo, Wang; Fan, Qiang; Peng, Qiwei; Cai, Yiting; Yao, Yiyang; Xu, Changfu

2018-01-01

This paper adopts a low power consumption ARM Hisilicon mobile processing platform and OV4689 camera, combined with a new skeleton extraction based on distance transform algorithm and the improved Hough algorithm for multi meters real-time reading. The design and implementation of the device were completed. Experimental results shows that The average error of measurement was 0.005MPa, and the average reading time was 5s. The device had good stability and high accuracy which meets the needs of practical application.

Broadband and stable acoustic vortex emitter with multi-arm coiling slits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Xue; Liang, Bin, E-mail: liangbin@nju.edu.cn, E-mail: eleqc@nus.edu.sg, E-mail: jccheng@nju.edu.cn; Zou, Xin-ye

2016-05-16

We present the analytical design and experimental realization of a scheme based on multi-arm coiling slits to generate the stable acoustic vortices in a broadband. The proposed structure is able to spiral the acoustic wave spatially and generate the twisted acoustic vortices with invariant topological charge for a long propagation distance. Compared with conventional methods which require the electronic control of a bulky loudspeaker, this scheme provides an effective and compact solution to generate acoustic vortices with controllable topological charge in the broadband, which offers more initiatives in the demanding applications.

Advanced design for orbital debris removal in support of solar system exploration

NASA Technical Reports Server (NTRS)

1991-01-01

The development of an Autonomous Space Processor for Orbital Debris (ASPOD) is the ultimate goal. The craft will process, in situ, orbital debris using resources available in low Earth orbit (LEO). The serious problem of orbital debris is briefly described and the nature of the large debris population is outlined. This year, focus was on development of a versatile robotic manipulator to augment an existing robotic arm; incorporation of remote operation of robotic arms; and formulation of optimal (time and energy) trajectory planning algorithms for coordinating robotic arms. The mechanical design of the new arm is described in detail. The versatile work envelope is explained showing the flexibility of the new design. Several telemetry communication systems are described which will enable the remote operation of the robotic arms. The trajectory planning algorithms are fully developed for both the time-optimal and energy-optimal problem. The optimal problem is solved using phase plane techniques while the energy optimal problem is solved using dynamics programming.

Autonomous space processor for orbital debris

NASA Technical Reports Server (NTRS)

Ramohalli, Kumar; Marine, Micky; Colvin, James; Crockett, Richard; Sword, Lee; Putz, Jennifer; Woelfle, Sheri

1991-01-01

The development of an Autonomous Space Processor for Orbital Debris (ASPOD) was the goal. The nature of this craft, which will process, in situ, orbital debris using resources available in low Earth orbit (LEO) is explained. The serious problem of orbital debris is briefly described and the nature of the large debris population is outlined. The focus was on the development of a versatile robotic manipulator to augment an existing robotic arm, the incorporation of remote operation of the robotic arms, and the formulation of optimal (time and energy) trajectory planning algorithms for coordinated robotic arms. The mechanical design of the new arm is described in detail. The work envelope is explained showing the flexibility of the new design. Several telemetry communication systems are described which will enable the remote operation of the robotic arms. The trajectory planning algorithms are fully developed for both the time optimal and energy optimal problems. The time optimal problem is solved using phase plane techniques while the energy optimal problem is solved using dynamic programming.

Using shape to turn off blinking for two-colour multiexciton emission in CdSe/CdS tetrapods

DOE PAGES

Mishra, Nimai; Orfield, Noah Jeremiah; Wang, Feng; ...

2017-05-12

Here, semiconductor nanostructures capable of emitting from two excited states and thereby of producing two photoluminescence colours are of fundamental and potential technological significance. In this limited class of nanocrystals, CdSe/CdS core/arm tetrapods exhibit the unusual trait of two-colour (red and green) multiexcitonic emission, with green emission from the CdS arms emerging only at high excitation fluences. Here we show that by synthetic shape-tuning, both this multi-colour emission process, and blinking and photobleaching behaviours of single tetrapods can be controlled. Specifically, we find that the properties of dual emission and single-nanostructure photostability depend on different structural parameters—arm length and armmore » diameter, respectively—but that both properties can be realized in the same nanostructure. Furthermore, based on results of correlated photoluminescence and transient absorption measurements, we conclude that hole-trap filling in the arms and partial state-filling in the core are necessary preconditions for the observation of multiexciton multi-colour emission.« less

Using shape to turn off blinking for two-colour multiexciton emission in CdSe/CdS tetrapods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mishra, Nimai; Orfield, Noah Jeremiah; Wang, Feng

Here, semiconductor nanostructures capable of emitting from two excited states and thereby of producing two photoluminescence colours are of fundamental and potential technological significance. In this limited class of nanocrystals, CdSe/CdS core/arm tetrapods exhibit the unusual trait of two-colour (red and green) multiexcitonic emission, with green emission from the CdS arms emerging only at high excitation fluences. Here we show that by synthetic shape-tuning, both this multi-colour emission process, and blinking and photobleaching behaviours of single tetrapods can be controlled. Specifically, we find that the properties of dual emission and single-nanostructure photostability depend on different structural parameters—arm length and armmore » diameter, respectively—but that both properties can be realized in the same nanostructure. Furthermore, based on results of correlated photoluminescence and transient absorption measurements, we conclude that hole-trap filling in the arms and partial state-filling in the core are necessary preconditions for the observation of multiexciton multi-colour emission.« less

A summary of recovery strategies for atmospheric fluxes affected by the Gill-Solent WindMaster-Pro "w-boost" firmware bug

NASA Astrophysics Data System (ADS)

Billesbach, D. P.; Chan, S.; Biraud, S.; Cook, D. R.

2016-12-01

In late 2015 and early 2016, work done by the AmeriFlux Tech Team helped to uncover a bug in the Gill WindMaster Pro sonic anemometers used by many researchers for eddy covariance flux measurements. Gill has addressed this issue and has since sent out a notice that the vertical wind speed component (a critical piece of all eddy covariance fluxes) was being erroneously computed and reported. The problem (known as the w-boost bug) resulted in positive (upward) wind speeds being under-reported by 16.6% and negative (downward) wind speeds being under-reported by 28.9%. This has the potential to cause similar underestimates in fluxes obtained from these instruments. While the manufacturer has offered a firmware upgrade to fix this bug, there exist many data sets that have already been affected by it. The DOE-ARM program makes extensive use of the affected instruments. We used a multi-year set of data from the ARM NSA (North Slope of Alaska) site near Barrow, AK and the AMF-3 (Arm Mobile Facility) located near Point Oliktok, AK to assess several proposed methods to correct existing flux data. We will outline those results in this presentation.

Evaluation of a multi-arm multi-stage Bayesian design for phase II drug selection trials - an example in hemato-oncology.

PubMed

Jacob, Louis; Uvarova, Maria; Boulet, Sandrine; Begaj, Inva; Chevret, Sylvie

2016-06-02

Multi-Arm Multi-Stage designs aim at comparing several new treatments to a common reference, in order to select or drop any treatment arm to move forward when such evidence already exists based on interim analyses. We redesigned a Bayesian adaptive design initially proposed for dose-finding, focusing our interest in the comparison of multiple experimental drugs to a control on a binary criterion measure. We redesigned a phase II clinical trial that randomly allocates patients across three (one control and two experimental) treatment arms to assess dropping decision rules. We were interested in dropping any arm due to futility, either based on historical control rate (first rule) or comparison across arms (second rule), and in stopping experimental arm due to its ability to reach a sufficient response rate (third rule), using the difference of response probabilities in Bayes binomial trials between the treated and control as a measure of treatment benefit. Simulations were then conducted to investigate the decision operating characteristics under a variety of plausible scenarios, as a function of the decision thresholds. Our findings suggest that one experimental treatment was less efficient than the control and could have been dropped from the trial based on a sample of approximately 20 instead of 40 patients. In the simulation study, stopping decisions were reached sooner for the first rule than for the second rule, with close mean estimates of response rates and small bias. According to the decision threshold, the mean sample size to detect the required 0.15 absolute benefit ranged from 63 to 70 (rule 3) with false negative rates of less than 2 % (rule 1) up to 6 % (rule 2). In contrast, detecting a 0.15 inferiority in response rates required a sample size ranging on average from 23 to 35 (rules 1 and 2, respectively) with a false positive rate ranging from 3.6 to 0.6 % (rule 3). Adaptive trial design is a good way to improve clinical trials. It allows removing ineffective drugs and reducing the trial sample size, while maintaining unbiased estimates. Decision thresholds can be set according to predefined fixed error decision rates. ClinicalTrials.gov Identifier: NCT01342692 .

Packaging Of Control Circuits In A Robot Arm

NASA Technical Reports Server (NTRS)

Kast, William

1994-01-01

Packaging system houses and connects control circuitry mounted on circuit boards within shoulder, upper section, and lower section of seven-degree-of-freedom robot arm. Has modular design that incorporates surface-mount technology, multilayer circuit boards, large-scale integrated circuits, and multi-layer flat cables between sections for compactness. Three sections of robot arm contain circuit modules in form of stardardized circuit boards. Each module contains two printed-circuit cards, one of each face.

The KALI multi-arm robot programming and control environment

NASA Technical Reports Server (NTRS)

Backes, Paul; Hayati, Samad; Hayward, Vincent; Tso, Kam

1989-01-01

The KALI distributed robot programming and control environment is described within the context of its use in the Jet Propulsion Laboratory (JPL) telerobot project. The purpose of KALI is to provide a flexible robot programming and control environment for coordinated multi-arm robots. Flexibility, both in hardware configuration and software, is desired so that it can be easily modified to test various concepts in robot programming and control, e.g., multi-arm control, force control, sensor integration, teleoperation, and shared control. In the programming environment, user programs written in the C programming language describe trajectories for multiple coordinated manipulators with the aid of KALI function libraries. A system of multiple coordinated manipulators is considered within the programming environment as one motion system. The user plans the trajectory of one controlled Cartesian frame associated with a motion system and describes the positions of the manipulators with respect to that frame. Smooth Cartesian trajectories are achieved through a blending of successive path segments. The manipulator and load dynamics are considered during trajectory generation so that given interface force limits are not exceeded.

Synergy effects of combined multichannel EMG-triggered electrical stimulation and mirror therapy in subacute stroke patients with severe or very severe arm/hand paresis.

PubMed

Schick, Thomas; Schlake, Hans-Peter; Kallusky, Juliane; Hohlfeld, Günter; Steinmetz, Maria; Tripp, Florian; Krakow, Karsten; Pinter, Michaela; Dohle, Christian

2017-01-01

Neurorehabilitation requires the development of severity-dependent and successful therapies for arm/hand rehabilitation in stroke patients. To evaluate the effectiveness of adding mirror therapy to bilateral EMG-triggered multi-channel electrostimulation for the treatment of severe arm/hand paresis in stroke patients. The subjects of this randomized, controlled, multicentre study were stroke patients who had suffered their first insult between 1 and 6 months before study start and had severe or very severe arm/hand paresis, as classified by Fugl-Meyer-Assessment. Subjects were randomly allocated to an intervention group (n = 16) or control group (n = 17). Both groups were treated for 3 weeks (5x week, 30 minutes) with bilateral EMG-triggered multi-channel electrostimulation. The intervention group additionally received mirror feedback of the unaffected limb. The primary outcome measure was motor recovery of the upper extremities, as measured by the Fugl-Meyer Assessment. The Intervention Group with very severe paresis had significantly better motor recovery in total Fugl-Meyer Assessment (p = 0.017) at a medium effect size (Cohen) of d = 0.7, due to a significant recovery of shoulder and elbow function (p = 0.003) in the Fugl-Meyer Assessment Part A subtest. For subjects with severe paresis, additional mirror therapy did not significantly influence outcome. Additional mirror therapy in combination with EMG-triggered multi-channel electrostimulation is therapeutically beneficial for post-acute stroke patients with very severe arm/hand paresis.

Application of Advanced Multi-Core Processor Technologies to Oceanographic Research

DTIC Science & Technology

2013-09-30

STM32 NXP LPC series No Proprietary Microchip PIC32/DSPIC No > 500 mW; < 5 W ARM Cortex TI OMAP TI Sitara Broadcom BCM2835 Varies FPGA...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Application of Advanced Multi-Core Processor Technologies...state-of-the-art information processing architectures. OBJECTIVES Next-generation processor architectures (multi-core, multi-threaded) hold the

Factorial versus multi-arm multi-stage designs for clinical trials with multiple treatments.

PubMed

Jaki, Thomas; Vasileiou, Despina

2017-02-20

When several treatments are available for evaluation in a clinical trial, different design options are available. We compare multi-arm multi-stage with factorial designs, and in particular, we will consider a 2 × 2 factorial design, where groups of patients will either take treatments A, B, both or neither. We investigate the performance and characteristics of both types of designs under different scenarios and compare them using both theory and simulations. For the factorial designs, we construct appropriate test statistics to test the hypothesis of no treatment effect against the control group with overall control of the type I error. We study the effect of the choice of the allocation ratios on the critical value and sample size requirements for a target power. We also study how the possibility of an interaction between the two treatments A and B affects type I and type II errors when testing for significance of each of the treatment effects. We present both simulation results and a case study on an osteoarthritis clinical trial. We discover that in an optimal factorial design in terms of minimising the associated critical value, the corresponding allocation ratios differ substantially to those of a balanced design. We also find evidence of potentially big losses in power in factorial designs for moderate deviations from the study design assumptions and little gain compared with multi-arm multi-stage designs when the assumptions hold. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

A multipurpose modular drone with adjustable arms produced via the FDM additive manufacturing process

NASA Astrophysics Data System (ADS)

Brischetto, Salvatore; Ciano, Alessandro; Ferro, Carlo Giovanni

2016-07-01

The present paper shows an innovative multirotor Unmanned Aerial Vehicle (UAV) which is able to easily and quickly change its configuration. In order to satisfy this feature, the principal structure is made of an universal plate, combined with a circular ring, to create a rail guide able to host the arms, in a variable number from 3 to 8, and the legs. The arms are adjustable and contain all the avionic and motor drivers to connect the main structure with each electric motor. The unique arm design, defined as all-in-one, allows classical single rotor configurations, double rotor configurations and amphibious configurations including inflatable elements positioned at the bottom of the arms. The proposed multi-rotor system is inexpensive because of the few universal pieces needed to compose the platform which allows the creation of a kit. This modular kit allows to have a modular drone with different configurations. Such configurations are distinguished among them for the number of arms, number of legs, number of rotors and motors, and landing capability. Another innovation feature is the introduction of the 3D printing technology to produce all the structural elements. In this manner, all the pieces are designed to be produced via the Fused Deposition Modelling (FDM) technology using desktop 3D printers. Therefore, an universal, dynamic and economic multi-rotor UAV has been developed.

Home Based Care as an Approach to Improve the Efficiency of treatment for MDR Tuberculosis: A Quasi-Experimental Pilot Study

PubMed Central

Taneja, Neha; Daral, Shailaja; Adhikary, Mrinmoy; Das, Timiresh Kumar

2017-01-01

Introduction Multi Drug Resistant Tuberculosis (MDR TB) has emerged as a significant public health problem in India. The prolonged treatment duration in MDR TB is a challenge in achieving treatment completion and poses a threat to TB control in the country. Home based care is an approach accepted by patients because it helps in ameliorating their understanding of TB, improving the compliance and reducing stigma in the community. Aim To assess the outcome of Home-Based Care (HC) versus No Home-Based Care (NHC) on the treatment of MDR TB patients registered at two chest clinics in Eastern Delhi. Materials and Methods A quasi-experimental study was done among diagnosed MDR TB patients receiving Category IV regimen under Revised National Tuberculosis Control Programme (RNTCP) from two government chest clinics in Eastern Delhi during May 2014 to May 2016. In the control arm, 50 MDR TB patients at one of the chest clinics were offered the standard Category IV regimen under RNTCP; while in the intervention arm, 50 MDR TB patients at the second chest clinic were provided home based care (counselling, support for completion of treatment, rehabilitation, and nutritional support) along with the standard treatment. The primary outcome assessed was outcome of treatment, while secondary outcomes included stigma faced due to the disease, and impact of disease on family and community life. Results The primary outcome data was available for 32 (64%) participants in the intervention arm, and 38 (76%) participants in control arm. The treatment was significantly more successful in the intervention arm (p<0.03). The data on secondary outcomes was available for all participants. Stigma due to disease was significantly lower in the intervention arm (p<0.01); also rejection faced by participants from family and community due to disease was significantly lower among the HC group (p<0.05). Conclusion Home-based care in MDR TB treatment holds potential in improving treatment outcomes of patient. PMID:28969162

Home Based Care as an Approach to Improve the Efficiency of treatment for MDR Tuberculosis: A Quasi-Experimental Pilot Study.

PubMed

Taneja, Neha; Chellaiyan, Vinoth Gnana; Daral, Shailaja; Adhikary, Mrinmoy; Das, Timiresh Kumar

2017-08-01

Multi Drug Resistant Tuberculosis (MDR TB) has emerged as a significant public health problem in India. The prolonged treatment duration in MDR TB is a challenge in achieving treatment completion and poses a threat to TB control in the country. Home based care is an approach accepted by patients because it helps in ameliorating their understanding of TB, improving the compliance and reducing stigma in the community. To assess the outcome of Home-Based Care (HC) versus No Home-Based Care (NHC) on the treatment of MDR TB patients registered at two chest clinics in Eastern Delhi. A quasi-experimental study was done among diagnosed MDR TB patients receiving Category IV regimen under Revised National Tuberculosis Control Programme (RNTCP) from two government chest clinics in Eastern Delhi during May 2014 to May 2016. In the control arm, 50 MDR TB patients at one of the chest clinics were offered the standard Category IV regimen under RNTCP; while in the intervention arm, 50 MDR TB patients at the second chest clinic were provided home based care (counselling, support for completion of treatment, rehabilitation, and nutritional support) along with the standard treatment. The primary outcome assessed was outcome of treatment, while secondary outcomes included stigma faced due to the disease, and impact of disease on family and community life. The primary outcome data was available for 32 (64%) participants in the intervention arm, and 38 (76%) participants in control arm. The treatment was significantly more successful in the intervention arm (p<0.03). The data on secondary outcomes was available for all participants. Stigma due to disease was significantly lower in the intervention arm (p<0.01); also rejection faced by participants from family and community due to disease was significantly lower among the HC group (p<0.05). Home-based care in MDR TB treatment holds potential in improving treatment outcomes of patient.

Utilising reinforcement learning to develop strategies for driving auditory neural implants.

PubMed

Lee, Geoffrey W; Zambetta, Fabio; Li, Xiaodong; Paolini, Antonio G

2016-08-01

In this paper we propose a novel application of reinforcement learning to the area of auditory neural stimulation. We aim to develop a simulation environment which is based off real neurological responses to auditory and electrical stimulation in the cochlear nucleus (CN) and inferior colliculus (IC) of an animal model. Using this simulator we implement closed loop reinforcement learning algorithms to determine which methods are most effective at learning effective acoustic neural stimulation strategies. By recording a comprehensive set of acoustic frequency presentations and neural responses from a set of animals we created a large database of neural responses to acoustic stimulation. Extensive electrical stimulation in the CN and the recording of neural responses in the IC provides a mapping of how the auditory system responds to electrical stimuli. The combined dataset is used as the foundation for the simulator, which is used to implement and test learning algorithms. Reinforcement learning, utilising a modified n-Armed Bandit solution, is implemented to demonstrate the model's function. We show the ability to effectively learn stimulation patterns which mimic the cochlea's ability to covert acoustic frequencies to neural activity. Time taken to learn effective replication using neural stimulation takes less than 20 min under continuous testing. These results show the utility of reinforcement learning in the field of neural stimulation. These results can be coupled with existing sound processing technologies to develop new auditory prosthetics that are adaptable to the recipients current auditory pathway. The same process can theoretically be abstracted to other sensory and motor systems to develop similar electrical replication of neural signals.

Stress as a one-armed bandit: Differential effects of stress paradigms on the morphology, neurochemistry and behavior in the rodent amygdala

PubMed Central

Wilson, Marlene A.; Grillo, Claudia A.; Fadel, Jim R.; Reagan, Lawrence P.

2015-01-01

Neuroplasticity may be defined as the ability of the central nervous system (CNS) to respond to changes in the internal and external environment and it is well established that some stimuli have the ability to facilitate or impair neuroplasticity depending on the pre-existing milieu. A classic example of a stimulus that can both facilitate and impair neuroplasticity is stress. Indeed, the ability of CNS to respond to acute stress is often dependent upon the prior stress history of the individual. While responses to acute stress are often viewed as adaptive in nature, stress reactivity in subjects with prior chronic stress experiences are often linked to neuropsychiatric disorders, including major depressive disorder, post-traumatic stress disorder (PTSD) and anxiety. In rodent studies, chronic stress exposure produces structural and functional alterations in the hippocampus and medial prefrontal cortex that are consistent across different types of stress paradigms. Conversely, the amygdala appears to exhibit differential structural and functional responses to stress that are dependent on a variety of factors, including the type of stressor performed and the duration of the stress paradigm. This is most evident in output measures including morphological analysis of amygdala neurons, measurement of glutamatergic tone in amygdalar subdivisions and the analysis of amygdala-centric behaviors. Accordingly, this review will provide an overview of the effects of stress on the structural and functional plasticity of the rodent amygdala, especially in relation to the differential effects of repeated or chronic stress paradigms on dendritic architecture, neurochemistry of the glutamatergic system and behavior. PMID:26844236

Reinforcement learning signals in the human striatum distinguish learners from nonlearners during reward-based decision making.

PubMed

Schönberg, Tom; Daw, Nathaniel D; Joel, Daphna; O'Doherty, John P

2007-11-21

The computational framework of reinforcement learning has been used to forward our understanding of the neural mechanisms underlying reward learning and decision-making behavior. It is known that humans vary widely in their performance in decision-making tasks. Here, we used a simple four-armed bandit task in which subjects are almost evenly split into two groups on the basis of their performance: those who do learn to favor choice of the optimal action and those who do not. Using models of reinforcement learning we sought to determine the neural basis of these intrinsic differences in performance by scanning both groups with functional magnetic resonance imaging. We scanned 29 subjects while they performed the reward-based decision-making task. Our results suggest that these two groups differ markedly in the degree to which reinforcement learning signals in the striatum are engaged during task performance. While the learners showed robust prediction error signals in both the ventral and dorsal striatum during learning, the nonlearner group showed a marked absence of such signals. Moreover, the magnitude of prediction error signals in a region of dorsal striatum correlated significantly with a measure of behavioral performance across all subjects. These findings support a crucial role of prediction error signals, likely originating from dopaminergic midbrain neurons, in enabling learning of action selection preferences on the basis of obtained rewards. Thus, spontaneously observed individual differences in decision making performance demonstrate the suggested dependence of this type of learning on the functional integrity of the dopaminergic striatal system in humans.

Advanced real-time multi-display educational system (ARMES): An innovative real-time audiovisual mentoring tool for complex robotic surgery.

PubMed

Lee, Joong Ho; Tanaka, Eiji; Woo, Yanghee; Ali, Güner; Son, Taeil; Kim, Hyoung-Il; Hyung, Woo Jin

2017-12-01

The recent scientific and technologic advances have profoundly affected the training of surgeons worldwide. We describe a novel intraoperative real-time training module, the Advanced Robotic Multi-display Educational System (ARMES). We created a real-time training module, which can provide a standardized step by step guidance to robotic distal subtotal gastrectomy with D2 lymphadenectomy procedures, ARMES. The short video clips of 20 key steps in the standardized procedure for robotic gastrectomy were created and integrated with TilePro™ software to delivery on da Vinci Surgical Systems (Intuitive Surgical, Sunnyvale, CA). We successfully performed the robotic distal subtotal gastrectomy with D2 lymphadenectomy for patient with gastric cancer employing this new teaching method without any transfer errors or system failures. Using this technique, the total operative time was 197 min and blood loss was 50 mL and there were no intra- or post-operative complications. Our innovative real-time mentoring module, ARMES, enables standardized, systematic guidance during surgical procedures. © 2017 Wiley Periodicals, Inc.

Technology Creep and the Arms Race: ICBM Problem a Sleeper.

PubMed

Shapley, D

1978-09-22

In three articles, Science will discuss how the creep of technology affects the arms race. The first two articles will deal with the most important current example: first, how ICBM modernization is giving both sides a destabilizing, first-strike capability, and second, how arms control seems to be dealing inadequately with this pressing problem. The third article will describe other cases of incremental technical improvements affecting arms control, such as antisatellite research and ballistic missile defense research, which are bringing both sides closer to the antiballistic missile capability they forswore in a 1972 treaty.

Compensation for loads during arm movements using equilibrium-point control.

PubMed

Gribble, P L; Ostry, D J

2000-12-01

A significant problem in motor control is how information about movement error is used to modify control signals to achieve desired performance. A potential source of movement error and one that is readily controllable experimentally relates to limb dynamics and associated movement-dependent loads. In this paper, we have used a position control model to examine changes to control signals for arm movements in the context of movement-dependent loads. In the model, based on the equilibrium-point hypothesis, equilibrium shifts are adjusted directly in proportion to the positional error between desired and actual movements. The model is used to simulate multi-joint movements in the presence of both "internal" loads due to joint interaction torques, and externally applied loads resulting from velocity-dependent force fields. In both cases it is shown that the model can achieve close correspondence to empirical data using a simple linear adaptation procedure. An important feature of the model is that it achieves compensation for loads during movement without the need for either coordinate transformations between positional error and associated corrective forces, or inverse dynamics calculations.

Comsat Antenna

NASA Technical Reports Server (NTRS)

1978-01-01

The antenna shown is the new, multiple-beam, Unattended Earth Terminal, located at COMSAT Laboratories in Clarksburg, Maryland. Seemingly simple, it is actually a complex structure capable of maintaining contact with several satellites simultaneously (conventional Earth station antennas communicate with only one satellite at a time). In developing the antenna, COMSAT Laboratories used NASTRAN, NASA's structural analysis computer program, together with BANDIT, a companion program. The computer programs were used to model several structural configurations and determine the most suitable, The speed and accuracy of the computerized design analysis afforded appreciable savings in time and money.

PAX-FOXO1 fusion status drives unfavorable outcome for children with rhabdomyosarcoma: a children's oncology group report.

PubMed

Skapek, Stephen X; Anderson, James; Barr, Frederic G; Bridge, Julia A; Gastier-Foster, Julie M; Parham, David M; Rudzinski, Erin R; Triche, Timothy; Hawkins, Douglas S

2013-09-01

Rhabdomyosarcoma (RMS) is divided into two major histological subtypes: alveolar (ARMS) and embryonal (ERMS), with most ARMS expressing one of two oncogenic genes fusing PAX3 or PAX7 with FOXO1 (P3F and P7F, respectively). The Children's Oncology Group (COG) carried out a multi-institutional clinical trial to evaluate the prognostic value of PAX-FOXO1 fusion status. Study participants were treated on COG protocol D9803 for intermediate risk ARMS or ERMS using multi-agent chemotherapy, radiotherapy, and surgery. Central diagnostic pathology review and molecular testing for fusion genes were carried out on prospectively collected specimens. Event-free (EFS) and overall survival (OS) at 5 years were correlated with histological subtype and PAX-FOXO1 status. Of 616 eligible D9803 enrollees, 434 cases had adequate clinical, molecular, and pathology data for definitive classification as ERMS, ARMS P3F+ or P7F+, or ARMSn (without detectable fusion). EFS was worse for those with ARMS P3F+ (54%) and P7F+ (65%) than those with ERMS (77%; P < 0.001). EFS for ARMSn and ERMS were not statistically different (90% vs. 77%, P = 0.15). ARMS P3F+ had poorer OS (64%) than ARMS P7F+ (87%), ARMSn (89%), and ERMS (82%; P = 0.006). ARMSn has an outcome similar to ERMS and superior EFS compared to ARMS with either P3F or P7F, when given therapy designed for children with intermediate risk RMS. This prospective analysis supports incorporation of PAX-FOXO1 fusion status into risk stratification and treatment allocation. Copyright © 2013 Wiley Periodicals, Inc.

PAX-FOXO1 Fusion Status Drives Unfavorable Outcome for Children With Rhabdomyosarcoma: A Children’s Oncology Group Report

PubMed Central

Skapek, Stephen X.; Anderson, James; Barr, Frederic G.; Bridge, Julia A.; Gastier-Foster, Julie M.; Parham, David M.; Rudzinski, Erin R.; Triche, Timothy; Hawkins, Douglas S.

2015-01-01

Background Rhabdomyosarcoma (RMS) is divided into two major histological subtypes: alveolar (ARMS) and embryonal (ERMS), with most ARMS expressing one of two oncogenic genes fusing PAX3 or PAX7 with FOXO1 (P3F and P7F, respectively). The Children’s Oncology Group (COG) carried out a multi-institutional clinical trial to evaluate the prognostic value of PAX-FOXO1 fusion status. Methods Study participants were treated on COG protocol D9803 for intermediate risk ARMS or ERMS using multi-agent chemotherapy, radiotherapy, and surgery. Central diagnostic pathology review and molecular testing for fusion genes were carried out on prospectively collected specimens. Event-free (EFS) and overall survival (OS) at 5 years were correlated with histological subtype and PAX-FOXO1 status. Results Of 616 eligible D9803 enrollees, 434 cases had adequate clinical, molecular, and pathology data for definitive classification as ERMS, ARMS P3F+ or P7F+, or ARMSn (without detectable fusion). EFS was worse for those with ARMS P3F+ (54%) and P7F+ (65%) than those with ERMS (77%; P < 0.001). EFS for ARMSn and ERMS were not statistically different (90% vs. 77%, P = 0.15). ARMS P3F+had poorer OS (64%) than ARMS P7F+ (87%), ARMSn (89%), and ERMS (82%; P = 0.006). Conclusions ARMSn has an outcome similar to ERMS and superior EFS compared to ARMS with either P3F or P7F, when given therapy designed for children with intermediate risk RMS. This prospective analysis supports incorporation of PAX-FOXO1 fusion status into risk stratification and treatment allocation. PMID:23526739

Multi-functional Electric Module for a Vehicle

NASA Technical Reports Server (NTRS)

Waligora, Thomas M. (Inventor); Fraser-Chanpong, Nathan (Inventor); Figuered, Joshua M. (Inventor); Reed, Ryan (Inventor); Akinyode, Akinjide Akinniyi (Inventor); Spain, Ivan (Inventor); Dawson, Andrew D. (Inventor); Herrera, Eduardo (Inventor); Markee, Mason M. (Inventor); Bluethmann, William J. (Inventor)

2015-01-01

A multi-functional electric module (eModule) is provided for a vehicle having a chassis, a master controller, and a drive wheel having a propulsion-braking module. The eModule includes a steering control assembly, mounting bracket, propulsion control assembly, brake controller, housing, and control arm. The steering control assembly includes a steering motor controlled by steering controllers in response to control signals from the master controller. A mounting feature of the bracket connects to the chassis. The propulsion control assembly and brake controller are in communication with the propulsion-braking module. The control arm connects to the lower portion and contains elements of a suspension system, with the control arm being connectable to the drive wheel via a wheel input/output block. The controllers are responsive to the master controller to control a respective steering, propulsion, and braking function. The steering motor may have a dual-wound stator with windings controlled via the respective steering controllers.

Overview of the United States Department of Energy's ARM (Atmospheric Radiation Measurement) Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stokes, G.M.; Tichler, J.L.

The Department of Energy (DOE) is initiating a major atmospheric research effort, the Atmospheric Radiation Measurement Program (ARM). The program is a key component of DOE's research strategy to address global climate change and is a direct continuation of DOE's decade-long effort to improve the ability of General Circulation Models (GCMs) to provide reliable simulations of regional, and long-term climate change in response to increasing greenhouse gases. The effort is multi-disciplinary and multi-agency, involving universities, private research organizations and more than a dozen government laboratories. The objective of the ARM Research is to provide an experimental testbed for the studymore » of important atmospheric effects, particularly cloud and radiative processes, and to test parameterizations of these processes for use in atmospheric models. This effort will support the continued and rapid improvement of GCM predictive capability. 2 refs.« less

CRUX: a Compliant Robotic Upper-Extremity eXosuit for Lightweight, Portable, Multi-DoF Muscular Augmentation

NASA Technical Reports Server (NTRS)

Lessard, Steven; Pansodtee, Pattawong; Robbins, Ash; Baltaxe-Admony, Leya Breanna; Teodorescu, Mircea; Kurniawan,Sri; Agogino, Adrian; Kurniawan, Sri

2017-01-01

Wearable robots can potentially offer their users enhanced stability and strength. These augmentations are ideally designed to actuate harmoniously with the users movements and provide extra force as needed. The creation of such robots, however, is particularly challenging due to the complexity of the underlying human body. In this paper, we present a compliant, robotic exosuit for upper-extremities called CRUX. This exosuit, inspired by tensegrity models of the human arm, features a lightweight (1.3 kg), flexible design for portability. We also show how CRUX maintains full flexibility of the upper-extremities for its users while providing multi- DoF augmentative strength to the major muscles of the arm, as evident by tracking the heart rate of an individual exercising said arm. Exosuits such as CRUX may be useful in physical therapy and in extreme environments where users are expected to exert their bodies to the fullest extent.

Lung-MAP Launches: First Precision Medicine Trial From National Clinical Trials Network

Cancer.gov

A unique public-private collaboration today announced the initiation of the Lung Cancer Master Protocol (Lung-MAP) trial, a multi-drug, multi-arm, biomarker-driven clinical trial for patients with advanced squamous cell lung cancer. Squamous cell carcinom

Research on the Optimization Method of Arm Movement in the Assembly Workshop Based on Ergonomics

NASA Astrophysics Data System (ADS)

Hu, X. M.; Qu, H. W.; Xu, H. J.; Yang, L.; Yu, C. C.

2017-12-01

In order to improve the work efficiency and comfortability, Ergonomics is used to research the work of the operator in the assembly workshop. An optimization algorithm of arm movement in the assembly workshop is proposed. In the algorithm, a mathematical model of arm movement is established based on multi rigid body movement model and D-H method. The solution of inverse kinematics equation on arm movement is solved through kinematics theory. The evaluation functions of each joint movement and the whole arm movement are given based on the comfortability of human body joint. The solution method of the optimal arm movement posture based on the evaluation functions is described. The software CATIA is used to verify that the optimal arm movement posture is valid in an example and the experimental result show the effectiveness of the algorithm.

Analysis of Multi-Arm Caliper Data for the U.S. Strategic Petroleum Reserve

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roberts, Barry L.

The U.S. Strategic Petroleum Reserve (SPR) has an increasing reliance on mul t i - arm caliper surveys to assess the integrity of casing for cavern access wells and to determine priorities for casing remediation. Multi - arm caliper (MAC) surveys provide a view of well casing deformation by reporting radial measurements of the inner cas ing wall as the tool is drawn through the casing. Over the last several years the SPR has collected a large number of modern MAC surveys. In total, these surveys account for over 100 million individual measurements. The surveys were collected using diff eringmore » survey vendors and survey hardware. This has resulted in a collection of disparate data sets which confound attempts to make well - to - well or time - dependent evaluations. In addition, the vendor supplied MAC interpretations often involve variables wh ich are not well defined or which may not be applicable to casings for cavern access wells. These factors reduce the usability of these detailed data sets. In order to address this issue and provide an independent analysis of multi - arm caliper survey data, Sandia National Labs has developed processing techniques and analysis variables which allow for the comparison of MAC survey data regardless of the source of the survey data. These techniques use the raw radial arm information and newly developed analysis variables to assess the casing status and provide a means for well - to - well and time - dependent analyses. Well - to - well and t ime - dependent investigation of the MAC survey data provide s information to prioritize well remediation activities and identify wells with integrity issues. This paper presents the challenges in using disparate MAC survey data, techniques developed to address these challenges and some o f the insights gained from these new techniques.« less

Short video interventions to reduce mental health stigma: a multi-centre randomised controlled trial in nursing high schools.

PubMed

Winkler, Petr; Janoušková, Miroslava; Kožený, Jiří; Pasz, Jiří; Mladá, Karolína; Weissová, Aneta; Tušková, Eva; Evans-Lacko, Sara

2017-12-01

We aimed to assess whether short video interventions could reduce stigma among nursing students. A multi-centre, randomised controlled trial was conducted. Participating schools were randomly selected and randomly assigned to receive: (1) an informational leaflet, (2) a short video intervention or (3) a seminar involving direct contact with a service user. The Community Attitudes towards Mental Illness (CAMI) and Reported and Intended Behaviour Scale (RIBS) were selected as primary outcome measures. SPANOVA models were built and Cohen's d calculated to assess the overall effects in each of the trial arms. Compared to the baseline, effect sizes immediately after the intervention were small in the flyer arm (CAMI: d = 0.25; RIBS: d = 0.07), medium in the seminar arm (CAMI: d = 0.61; RIBS: d = 0.58), and medium in the video arm (CAMI: d = 0.49 RIBS: d = 0.26; n = 237). Effect sizes at the follow-up were vanishing in the flyer arm (CAMI: d = 0.05; RIBS: d = 0.04), medium in the seminar arm (CAMI: d = 0.43; RIBS: d = 0.26; n = 254), and small in the video arm (CAMI: d = 0.22 RIBS: d = 0.21; n = 237). Seminar had the strongest and relatively stable effect on students' attitudes and intended behaviour, but the effect of short video interventions was also considerable and stable over time. Since short effective video interventions are relatively cheap, conveniently accessible and easy to disseminate globally, we recommend them for further research and development.

A Performance Comparison of the Parallel Preconditioners for Iterative Methods for Large Sparse Linear Systems Arising from Partial Differential Equations on Structured Grids

NASA Astrophysics Data System (ADS)

Ma, Sangback

In this paper we compare various parallel preconditioners such as Point-SSOR (Symmetric Successive OverRelaxation), ILU(0) (Incomplete LU) in the Wavefront ordering, ILU(0) in the Multi-color ordering, Multi-Color Block SOR (Successive OverRelaxation), SPAI (SParse Approximate Inverse) and pARMS (Parallel Algebraic Recursive Multilevel Solver) for solving large sparse linear systems arising from two-dimensional PDE (Partial Differential Equation)s on structured grids. Point-SSOR is well-known, and ILU(0) is one of the most popular preconditioner, but it is inherently serial. ILU(0) in the Wavefront ordering maximizes the parallelism in the natural order, but the lengths of the wave-fronts are often nonuniform. ILU(0) in the Multi-color ordering is a simple way of achieving a parallelism of the order N, where N is the order of the matrix, but its convergence rate often deteriorates as compared to that of natural ordering. We have chosen the Multi-Color Block SOR preconditioner combined with direct sparse matrix solver, since for the Laplacian matrix the SOR method is known to have a nondeteriorating rate of convergence when used with the Multi-Color ordering. By using block version we expect to minimize the interprocessor communications. SPAI computes the sparse approximate inverse directly by least squares method. Finally, ARMS is a preconditioner recursively exploiting the concept of independent sets and pARMS is the parallel version of ARMS. Experiments were conducted for the Finite Difference and Finite Element discretizations of five two-dimensional PDEs with large meshsizes up to a million on an IBM p595 machine with distributed memory. Our matrices are real positive, i. e., their real parts of the eigenvalues are positive. We have used GMRES(m) as our outer iterative method, so that the convergence of GMRES(m) for our test matrices are mathematically guaranteed. Interprocessor communications were done using MPI (Message Passing Interface) primitives. The results show that in general ILU(0) in the Multi-Color ordering ahd ILU(0) in the Wavefront ordering outperform the other methods but for symmetric and nearly symmetric 5-point matrices Multi-Color Block SOR gives the best performance, except for a few cases with a small number of processors.

Design of multi-function sensor detection system in coal mine based on ARM

NASA Astrophysics Data System (ADS)

Ge, Yan-Xiang; Zhang, Quan-Zhu; Deng, Yong-Hong

2017-06-01

The traditional coal mine sensor in the specific measurement points, the number and type of channel will be greater than or less than the number of monitoring points, resulting in a waste of resources or cannot meet the application requirements, in order to enable the sensor to adapt to the needs of different occasions and reduce the cost, a kind of multi-functional intelligent sensor multiple sensors and ARM11 the S3C6410 processor is used to design and realize the dust, gas, temperature and humidity sensor functions together, and has storage, display, voice, pictures, data query, alarm and other new functions.

CCPP-ARM Parameterization Testbed Model Forecast Data

DOE Data Explorer

Klein, Stephen

2008-01-15

Dataset contains the NCAR CAM3 (Collins et al., 2004) and GFDL AM2 (GFDL GAMDT, 2004) forecast data at locations close to the ARM research sites. These data are generated from a series of multi-day forecasts in which both CAM3 and AM2 are initialized at 00Z every day with the ECMWF reanalysis data (ERA-40), for the year 1997 and 2000 and initialized with both the NASA DAO Reanalyses and the NCEP GDAS data for the year 2004. The DOE CCPP-ARM Parameterization Testbed (CAPT) project assesses climate models using numerical weather prediction techniques in conjunction with high quality field measurements (e.g. ARM data).

Accelerating clinical development of HIV vaccine strategies: methodological challenges and considerations in constructing an optimised multi-arm phase I/II trial design.

PubMed

Richert, Laura; Doussau, Adélaïde; Lelièvre, Jean-Daniel; Arnold, Vincent; Rieux, Véronique; Bouakane, Amel; Lévy, Yves; Chêne, Geneviève; Thiébaut, Rodolphe

2014-02-26

Many candidate vaccine strategies against human immunodeficiency virus (HIV) infection are under study, but their clinical development is lengthy and iterative. To accelerate HIV vaccine development optimised trial designs are needed. We propose a randomised multi-arm phase I/II design for early stage development of several vaccine strategies, aiming at rapidly discarding those that are unsafe or non-immunogenic. We explored early stage designs to evaluate both the safety and the immunogenicity of four heterologous prime-boost HIV vaccine strategies in parallel. One of the vaccines used as a prime and boost in the different strategies (vaccine 1) has yet to be tested in humans, thus requiring a phase I safety evaluation. However, its toxicity risk is considered minimal based on data from similar vaccines. We newly adapted a randomised phase II trial by integrating an early safety decision rule, emulating that of a phase I study. We evaluated the operating characteristics of the proposed design in simulation studies with either a fixed-sample frequentist or a continuous Bayesian safety decision rule and projected timelines for the trial. We propose a randomised four-arm phase I/II design with two independent binary endpoints for safety and immunogenicity. Immunogenicity evaluation at trial end is based on a single-stage Fleming design per arm, comparing the observed proportion of responders in an immunogenicity screening assay to an unacceptably low proportion, without direct comparisons between arms. Randomisation limits heterogeneity in volunteer characteristics between arms. To avoid exposure of additional participants to an unsafe vaccine during the vaccine boost phase, an early safety decision rule is imposed on the arm starting with vaccine 1 injections. In simulations of the design with either decision rule, the risks of erroneous conclusions were controlled <15%. Flexibility in trial conduct is greater with the continuous Bayesian rule. A 12-month gain in timelines is expected by this optimised design. Other existing designs such as bivariate or seamless phase I/II designs did not offer a clear-cut alternative. By combining phase I and phase II evaluations in a multi-arm trial, the proposed optimised design allows for accelerating early stage clinical development of HIV vaccine strategies.

TARGETED SEQUENTIAL DESIGN FOR TARGETED LEARNING INFERENCE OF THE OPTIMAL TREATMENT RULE AND ITS MEAN REWARD.

PubMed

Chambaz, Antoine; Zheng, Wenjing; van der Laan, Mark J

2017-01-01

This article studies the targeted sequential inference of an optimal treatment rule (TR) and its mean reward in the non-exceptional case, i.e. , assuming that there is no stratum of the baseline covariates where treatment is neither beneficial nor harmful, and under a companion margin assumption. Our pivotal estimator, whose definition hinges on the targeted minimum loss estimation (TMLE) principle, actually infers the mean reward under the current estimate of the optimal TR. This data-adaptive statistical parameter is worthy of interest on its own. Our main result is a central limit theorem which enables the construction of confidence intervals on both mean rewards under the current estimate of the optimal TR and under the optimal TR itself. The asymptotic variance of the estimator takes the form of the variance of an efficient influence curve at a limiting distribution, allowing to discuss the efficiency of inference. As a by product, we also derive confidence intervals on two cumulated pseudo-regrets, a key notion in the study of bandits problems. A simulation study illustrates the procedure. One of the corner-stones of the theoretical study is a new maximal inequality for martingales with respect to the uniform entropy integral.

An Overview of NASA's Asteroid Redirect Mission (ARM) Concept

NASA Technical Reports Server (NTRS)

Abell, P. A.; Mazanek, D. D.; Reeves, D. M.; Chodas, P. W.; Gates, M. M.; Johnson, L. N.; Ticker, R. L.

2016-01-01

The National Aeronautics and Space Administration (NASA) is developing the Asteroid Redirect Mission (ARM) as a capability demonstration for future human exploration, including use of high-power solar electric propulsion, which allows for the efficient movement of large masses through deep space. The ARM will also demonstrate the capability to conduct proximity operations with natural space objects and crewed operations beyond the security of quick Earth return. The Asteroid Redirect Robotic Mission (ARRM), currently in formulation, will visit a large near-Earth asteroid (NEA), collect a multi-ton boulder from its surface, conduct a demonstration of a slow push planetary defense technique, and redirect the multi-ton boulder into a stable orbit around the Moon. Once returned to cislunar space in the mid-2020s, astronauts aboard an Orion spacecraft will dock with the robotic vehicle to explore the boulder and return samples to Earth. The ARM is part of NASA's plan to advance technologies, capabilities, and spaceflight experience needed for a human mission to the Martian system in the 2030s. The ARM and subsequent availability of the asteroidal material in cis-lunar space, provide significant opportunities to advance our knowledge of small bodies in the synergistic areas of science, planetary defense, and in-situ resource utilization (ISRU). NASA established the Formulation Assessment and Support Team (FAST), comprised of scientists, engineers, and technologists, which supported ARRM mission requirements formulation, answered specific questions concerning potential target asteroid physical properties, and produced a publically available report. The ARM Investigation Team is being organized to support ARM implementation and execution. NASA is also open to collaboration with its international partners and welcomes further discussions. An overview of the ARM robotic and crewed segments, including mission requirements, NEA targets, and mission operations, and a discussion of potential opportunities for participation with the ARM will be provided.

Automatic motor task selection via a bandit algorithm for a brain-controlled button

NASA Astrophysics Data System (ADS)

Fruitet, Joan; Carpentier, Alexandra; Munos, Rémi; Clerc, Maureen

2013-02-01

Objective. Brain-computer interfaces (BCIs) based on sensorimotor rhythms use a variety of motor tasks, such as imagining moving the right or left hand, the feet or the tongue. Finding the tasks that yield best performance, specifically to each user, is a time-consuming preliminary phase to a BCI experiment. This study presents a new adaptive procedure to automatically select (online) the most promising motor task for an asynchronous brain-controlled button. Approach. We develop for this purpose an adaptive algorithm UCB-classif based on the stochastic bandit theory and design an EEG experiment to test our method. We compare (offline) the adaptive algorithm to a naïve selection strategy which uses uniformly distributed samples from each task. We also run the adaptive algorithm online to fully validate the approach. Main results. By not wasting time on inefficient tasks, and focusing on the most promising ones, this algorithm results in a faster task selection and a more efficient use of the BCI training session. More precisely, the offline analysis reveals that the use of this algorithm can reduce the time needed to select the most appropriate task by almost half without loss in precision, or alternatively, allow us to investigate twice the number of tasks within a similar time span. Online tests confirm that the method leads to an optimal task selection. Significance. This study is the first one to optimize the task selection phase by an adaptive procedure. By increasing the number of tasks that can be tested in a given time span, the proposed method could contribute to reducing ‘BCI illiteracy’.

[Radiative and hygienic certification in Armed Forces, problems of its implementation and ways of perfection].

PubMed

Rusakov, V N; Cherkashin, A V; Shishkanov, A P; Ian'shin, L A; Gracheva, T N

2010-12-01

Radiative and hygienic passportization is one of the most actual pattern of socio and hygienic monitoring in Armed Forces. Radiative and hygienic passport is the main document which characterizes the safety control in military unit and uses the sources of ionizing radiation. Sanitary and epidemiologic institutions were imputed to control the formation of radiative and hygienic passports, analysis and generalization of its data, formation of conclusions about the condition of radiation security in the military units. According to radiative and hygienic passportization, which took place in 2009, the radiation security in the Armed Forces and organizations is satisfactory, but there are some problems of providing of radiation security of personnel under the professional and medical radiation. The salvation of its problems requires the effective work of official functionary of radiac object and institutions of state sanitary and epidemiological supervision in Armed Forces of Russian Federation.

The Role of the Scientific Community in the Conversion of the Arms Industry.

ERIC Educational Resources Information Center

Faramazjan, Rachik

1983-01-01

Scientists' role in the conversion of the arms industry is discussed in the context of research and solutions to economic problems related to arms conversion. Suggestions for preparing to undertake arms conversion based on Russia's postwar experience are presented. Scientists should prove that disarmament is desirable and will benefit humanity.…

Arms Control and Disarmament, Volume 8, Number 2, Spring 1972. A Quarterly Bibliography with Abstracts and Annotations

DTIC Science & Technology

Contents: Preface; The international political environment; The strategic environment; Institutions and means for the maintenance of peace; Arms control--general discussion; Arms control--specific problems and measures; Author index ; Subject index.

Improving lateral resolution and image quality of optical coherence tomography by the multi-frame superresolution technique for 3D tissue imaging.

PubMed

Shen, Kai; Lu, Hui; Baig, Sarfaraz; Wang, Michael R

2017-11-01

The multi-frame superresolution technique is introduced to significantly improve the lateral resolution and image quality of spectral domain optical coherence tomography (SD-OCT). Using several sets of low resolution C-scan 3D images with lateral sub-spot-spacing shifts on different sets, the multi-frame superresolution processing of these sets at each depth layer reconstructs a higher resolution and quality lateral image. Layer by layer processing yields an overall high lateral resolution and quality 3D image. In theory, the superresolution processing including deconvolution can solve the diffraction limit, lateral scan density and background noise problems together. In experiment, the improved lateral resolution by ~3 times reaching 7.81 µm and 2.19 µm using sample arm optics of 0.015 and 0.05 numerical aperture respectively as well as doubling the image quality has been confirmed by imaging a known resolution test target. Improved lateral resolution on in vitro skin C-scan images has been demonstrated. For in vivo 3D SD-OCT imaging of human skin, fingerprint and retina layer, we used the multi-modal volume registration method to effectively estimate the lateral image shifts among different C-scans due to random minor unintended live body motion. Further processing of these images generated high lateral resolution 3D images as well as high quality B-scan images of these in vivo tissues.

Counselling in Areas of Armed Conflict: The Case Jaffna, Sri Lanka.

ERIC Educational Resources Information Center

van der Veer, Guus; Somasundaram, Daya; Damian S.

2003-01-01

Counseling is discussed in relation to traditional resources of the Tamil community for dealing with psychosocial and mental health problems. Describes some problems of clients affected by the armed conflict, approaches of local counselors and mental health professionals, and training offered to future Sri Lankan counselors who want to work with…

Naval War College Review. Volume 63, Number 1, Winter 2010

DTIC Science & Technology

2010-01-01

Impeccable Incident. Summer 2009:101–11 Raymond, Catherine Zara . Piracy and Armed Robbery in the Malacca Strait: A Problem Solved? Summer 2009:31–42...an Old Problem: Report of the Naval War College Workshop on Countering Maritime Piracy. Autumn 2009:141–54 Raymond, Catherine Zara . Piracy and Armed

Rethinking non-inferiority: a practical trial design for optimising treatment duration.

PubMed

Quartagno, Matteo; Walker, A Sarah; Carpenter, James R; Phillips, Patrick Pj; Parmar, Mahesh Kb

2018-06-01

Background Trials to identify the minimal effective treatment duration are needed in different therapeutic areas, including bacterial infections, tuberculosis and hepatitis C. However, standard non-inferiority designs have several limitations, including arbitrariness of non-inferiority margins, choice of research arms and very large sample sizes. Methods We recast the problem of finding an appropriate non-inferior treatment duration in terms of modelling the entire duration-response curve within a pre-specified range. We propose a multi-arm randomised trial design, allocating patients to different treatment durations. We use fractional polynomials and spline-based methods to flexibly model the duration-response curve. We call this a 'Durations design'. We compare different methods in terms of a scaled version of the area between true and estimated prediction curves. We evaluate sensitivity to key design parameters, including sample size, number and position of arms. Results A total sample size of ~ 500 patients divided into a moderate number of equidistant arms (5-7) is sufficient to estimate the duration-response curve within a 5% error margin in 95% of the simulations. Fractional polynomials provide similar or better results than spline-based methods in most scenarios. Conclusion Our proposed practical randomised trial 'Durations design' shows promising performance in the estimation of the duration-response curve; subject to a pending careful investigation of its inferential properties, it provides a potential alternative to standard non-inferiority designs, avoiding many of their limitations, and yet being fairly robust to different possible duration-response curves. The trial outcome is the whole duration-response curve, which may be used by clinicians and policymakers to make informed decisions, facilitating a move away from a forced binary hypothesis testing paradigm.

The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

NASA Astrophysics Data System (ADS)

Ma, Xiaoping; Li, Dianzhong

2018-07-01

The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

NASA Astrophysics Data System (ADS)

Ma, Xiaoping; Li, Dianzhong

2018-03-01

The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

Multi-pose system for geometric measurement of large-scale assembled rotational parts

NASA Astrophysics Data System (ADS)

Deng, Bowen; Wang, Zhaoba; Jin, Yong; Chen, Youxing

2017-05-01

To achieve virtual assembly of large-scale assembled rotational parts based on in-field geometric data, we develop a multi-pose rotative arm measurement system with a gantry and 2D laser sensor (RAMSGL) to measure and provide the geometry of these parts. We mount a 2D laser sensor onto the end of a six-jointed rotative arm to guarantee the accuracy and efficiency, combine the rotative arm with a gantry to measure pairs of assembled rotational parts. By establishing and using the D-H model of the system, the 2D laser data is turned into point clouds and finally geometry is calculated. In addition, we design three experiments to evaluate the performance of the system. Experimental results show that the system’s max length measuring deviation using gauge blocks is 35 µm, max length measuring deviation using ball plates is 50 µm, max single-point repeatability error is 25 µm, and measurement scope is from a radius of 0 mm to 500 mm.

Coupling of Lever Arm Swing and Biased Brownian Motion in Actomyosin

PubMed Central

Nie, Qing-Miao; Togashi, Akio; Sasaki, Takeshi N.; Takano, Mitsunori; Sasai, Masaki; Terada, Tomoki P.

2014-01-01

An important unresolved problem associated with actomyosin motors is the role of Brownian motion in the process of force generation. On the basis of structural observations of myosins and actins, the widely held lever-arm hypothesis has been proposed, in which proteins are assumed to show sequential structural changes among observed and hypothesized structures to exert mechanical force. An alternative hypothesis, the Brownian motion hypothesis, has been supported by single-molecule experiments and emphasizes more on the roles of fluctuating protein movement. In this study, we address the long-standing controversy between the lever-arm hypothesis and the Brownian motion hypothesis through in silico observations of an actomyosin system. We study a system composed of myosin II and actin filament by calculating free-energy landscapes of actin-myosin interactions using the molecular dynamics method and by simulating transitions among dynamically changing free-energy landscapes using the Monte Carlo method. The results obtained by this combined multi-scale calculation show that myosin with inorganic phosphate (Pi) and ADP weakly binds to actin and that after releasing Pi and ADP, myosin moves along the actin filament toward the strong-binding site by exhibiting the biased Brownian motion, a behavior consistent with the observed single-molecular behavior of myosin. Conformational flexibility of loops at the actin-interface of myosin and the N-terminus of actin subunit is necessary for the distinct bias in the Brownian motion. Both the 5.5–11 nm displacement due to the biased Brownian motion and the 3–5 nm displacement due to lever-arm swing contribute to the net displacement of myosin. The calculated results further suggest that the recovery stroke of the lever arm plays an important role in enhancing the displacement of myosin through multiple cycles of ATP hydrolysis, suggesting a unified movement mechanism for various members of the myosin family. PMID:24762409

Coupling of lever arm swing and biased Brownian motion in actomyosin.

PubMed

Nie, Qing-Miao; Togashi, Akio; Sasaki, Takeshi N; Takano, Mitsunori; Sasai, Masaki; Terada, Tomoki P

2014-04-01

An important unresolved problem associated with actomyosin motors is the role of Brownian motion in the process of force generation. On the basis of structural observations of myosins and actins, the widely held lever-arm hypothesis has been proposed, in which proteins are assumed to show sequential structural changes among observed and hypothesized structures to exert mechanical force. An alternative hypothesis, the Brownian motion hypothesis, has been supported by single-molecule experiments and emphasizes more on the roles of fluctuating protein movement. In this study, we address the long-standing controversy between the lever-arm hypothesis and the Brownian motion hypothesis through in silico observations of an actomyosin system. We study a system composed of myosin II and actin filament by calculating free-energy landscapes of actin-myosin interactions using the molecular dynamics method and by simulating transitions among dynamically changing free-energy landscapes using the Monte Carlo method. The results obtained by this combined multi-scale calculation show that myosin with inorganic phosphate (Pi) and ADP weakly binds to actin and that after releasing Pi and ADP, myosin moves along the actin filament toward the strong-binding site by exhibiting the biased Brownian motion, a behavior consistent with the observed single-molecular behavior of myosin. Conformational flexibility of loops at the actin-interface of myosin and the N-terminus of actin subunit is necessary for the distinct bias in the Brownian motion. Both the 5.5-11 nm displacement due to the biased Brownian motion and the 3-5 nm displacement due to lever-arm swing contribute to the net displacement of myosin. The calculated results further suggest that the recovery stroke of the lever arm plays an important role in enhancing the displacement of myosin through multiple cycles of ATP hydrolysis, suggesting a unified movement mechanism for various members of the myosin family.

Closed-Loop Neuroprosthesis for Reach-to-Grasp Assistance: Combining Adaptive Multi-channel Neuromuscular Stimulation with a Multi-joint Arm Exoskeleton.

PubMed

Grimm, Florian; Gharabaghi, Alireza

2016-01-01

Stroke patients with severe motor deficits cannot execute task-oriented rehabilitation exercises with their affected upper extremity. Advanced rehabilitation technology may support them in performing such reach-to-grasp movements. The challenge is, however, to provide assistance as needed, while maintaining the participants' commitment during the exercises. In this feasibility study, we introduced a closed-loop neuroprosthesis for reach-to-grasp assistance which combines adaptive multi-channel neuromuscular stimulation with a multi-joint arm exoskeleton. Eighteen severely affected chronic stroke patients were assisted by a gravity-compensating, seven-degree-of-freedom exoskeleton which was attached to the paretic arm for performing reach-to-grasp exercises resembling activities of daily living in a virtual environment. During the exercises, adaptive electrical stimulation was applied to seven different muscles of the upper extremity in a performance-dependent way to enhance the task-oriented movement trajectory. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e., induced no overt support. Closed-loop neuromuscular stimulation could be well integrated into the exoskeleton-based training, and increased the task-related range of motion (p = 0.0004) and movement velocity (p = 0.015), while preserving accuracy. The highest relative stimulation intensity was required to facilitate the grasping function. The facilitated range of motion correlated with the upper extremity Fugl-Meyer Assessment score of the patients (p = 0.028). Combining adaptive multi-channel neuromuscular stimulation with antigravity assistance amplifies the residual motor capabilities of severely affected stroke patients during rehabilitation exercises and may thus provide a customized training environment for patient-tailored support while preserving the participants' engagement.

Closed-Loop Neuroprosthesis for Reach-to-Grasp Assistance: Combining Adaptive Multi-channel Neuromuscular Stimulation with a Multi-joint Arm Exoskeleton

PubMed Central

Grimm, Florian; Gharabaghi, Alireza

2016-01-01

Stroke patients with severe motor deficits cannot execute task-oriented rehabilitation exercises with their affected upper extremity. Advanced rehabilitation technology may support them in performing such reach-to-grasp movements. The challenge is, however, to provide assistance as needed, while maintaining the participants' commitment during the exercises. In this feasibility study, we introduced a closed-loop neuroprosthesis for reach-to-grasp assistance which combines adaptive multi-channel neuromuscular stimulation with a multi-joint arm exoskeleton. Eighteen severely affected chronic stroke patients were assisted by a gravity-compensating, seven-degree-of-freedom exoskeleton which was attached to the paretic arm for performing reach-to-grasp exercises resembling activities of daily living in a virtual environment. During the exercises, adaptive electrical stimulation was applied to seven different muscles of the upper extremity in a performance-dependent way to enhance the task-oriented movement trajectory. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e., induced no overt support. Closed-loop neuromuscular stimulation could be well integrated into the exoskeleton-based training, and increased the task-related range of motion (p = 0.0004) and movement velocity (p = 0.015), while preserving accuracy. The highest relative stimulation intensity was required to facilitate the grasping function. The facilitated range of motion correlated with the upper extremity Fugl-Meyer Assessment score of the patients (p = 0.028). Combining adaptive multi-channel neuromuscular stimulation with antigravity assistance amplifies the residual motor capabilities of severely affected stroke patients during rehabilitation exercises and may thus provide a customized training environment for patient-tailored support while preserving the participants' engagement. PMID:27445658

Quantitative assessment of ischemia and reactive hyperemia of the dermal layers using multi - spectral imaging on the human arm

NASA Astrophysics Data System (ADS)

Kainerstorfer, Jana M.; Amyot, Franck; Demos, Stavros G.; Hassan, Moinuddin; Chernomordik, Victor; Hitzenberger, Christoph K.; Gandjbakhche, Amir H.; Riley, Jason D.

2009-07-01

Quantitative assessment of skin chromophores in a non-invasive fashion is often desirable. Especially pixel wise assessment of blood volume and blood oxygenation is beneficial for improved diagnostics. We utilized a multi-spectral imaging system for acquiring diffuse reflectance images of healthy volunteers' lower forearm. Ischemia and reactive hyperemia was introduced by occluding the upper arm with a pressure cuff for 5min with 180mmHg. Multi-spectral images were taken every 30s, before, during and after occlusion. Image reconstruction for blood volume and blood oxygenation was performed, using a two layered skin model. As the images were taken in a non-contact way, strong artifacts related to the shape (curvature) of the arms were observed, making reconstruction of optical / physiological parameters highly inaccurate. We developed a curvature correction method, which is based on extracting the curvature directly from the intensity images acquired and does not require any additional measures on the object imaged. The effectiveness of the algorithm was demonstrated, on reconstruction results of blood volume and blood oxygenation for in vivo data during occlusion of the arm. Pixel wise assessment of blood volume and blood oxygenation was made possible over the entire image area and comparison of occlusion effects between veins and surrounding skin was performed. Induced ischemia during occlusion and reactive hyperemia afterwards was observed and quantitatively assessed. Furthermore, the influence of epidermal thickness on reconstruction results was evaluated and the exact knowledge of this parameter for fully quantitative assessment was pointed out.

The Asteroid Redirect Mission (ARM): Exploration of a Former Binary NEA?

NASA Technical Reports Server (NTRS)

Abell, P. A.; Mazanek, D. D.; Reeves, D. M.; Chodas, P. W.; Gates, M. M.; Johnson, L. N.; Ticker, R. L.

2016-01-01

The National Aeronautics and Space Administration (NASA) is developing the Asteroid Redirect Mission (ARM) as a capability demonstration for future human exploration, including use of high-power solar electric propulsion, which allows for the efficient movement of large masses through deep space. The ARM will also demonstrate the capability to conduct proximity operations with natural space objects and crewed operations beyond the security of quick Earth return. The Asteroid Redirect Robotic Mission (ARRM), currently in formulation, will visit a large near-Earth asteroid (NEA), collect a multi-ton boulder from its surface, conduct a demonstration of a slow push planetary defense technique, and redirect the multi-ton boulder into a stable orbit around the Moon. Once returned to cislunar space in the mid-2020s, astronauts aboard an Orion spacecraft will dock with the robotic vehicle to explore the boulder and return samples to Earth. The ARM is part of NASA's plan to advance technologies, capabilities, and spaceflight experience needed for a human mission to the Martian system in the 2030s. The ARM and subsequent availability of the asteroidal material in cis-lunar space, provide significant opportunities to advance our knowledge of small bodies in the synergistic areas of science, planetary defense, and in-situ resource utilization (ISRU). The current reference target for the ARM is NEA (341843) 2008 EV5, which may have been the primary body of a former binary system (Busch et al., 2011; Tardivel et al., 2016). The ARRM will perform several close proximity operations to investigate the NEA and map its surface. A detailed investigation of this object may allow a better understanding of binary NEA physical characteristics and the possible outcomes for their evolution. An overview of the ARM robotic and crewed segments, including mission operations, and a discussion of potential opportunities for participation with the ARM will be provided in this presentation.

Multi-access laser communications terminal

NASA Technical Reports Server (NTRS)

1992-01-01

The Optical Multi-Access (OMA) Terminal is capable of establishing up to six simultaneous high-data-rate communication links between low-Earth-orbit satellites and a host satellite at synchronous orbit with only one 16-inch-diameter antenna on the synchronous satellite. The advantage over equivalent RF systems in space weight, power, and swept volume is great when applied to NASA satellite communications networks. A photograph of the 3-channel prototype constructed under the present contract to demonstrate the feasibility of the concept is presented. The telescope has a 10-inch clear aperture and a 22 deg full field of view. It consists of 4 refractive elements to achieve a telecentric focus, i.e., the focused beam is normal to the focal plane at all field angles. This feature permits image pick-up optics in the focal plane to track satellite images without tilting their optic axes to accommodate field angle. The geometry of the imager-pick-up concept and the coordinate system of the swinging arm and disk mechanism for image pick-up are shown. Optics in the arm relay the telescope focus to a communications and tracking receiver and introduce the transmitted beacon beam on a path collinear with the receive path. The electronic circuits for the communications and tracking receivers are contained on the arm and disk assemblies and relay signals to an associated PC-based operator's console for control of the arm and disk motor drive through a flexible cable which permits +/- 240 deg travel for each arm and disk assembly. Power supplies and laser transmitters are mounted in the cradle for the telescope. A single-mode fiber in the cable is used to carry the laser transmitter signal to the arm optics. The promise of the optical multi-access terminal towards which the prototype effort worked is shown. The emphasis in the prototype development was the demonstration of the unique aspect of the concept, and where possible, cost avoidance compromises were implemented in areas already proven on other programs. The design details are described in section 2, the prototype test results in section 3, additional development required in section 4, and conclusions in section 5.

Effects of Ventral Striatum Lesions on Stimulus-Based versus Action-Based Reinforcement Learning.

PubMed

Rothenhoefer, Kathryn M; Costa, Vincent D; Bartolo, Ramón; Vicario-Feliciano, Raquel; Murray, Elisabeth A; Averbeck, Bruno B

2017-07-19

Learning the values of actions versus stimuli may depend on separable neural circuits. In the current study, we evaluated the performance of rhesus macaques with ventral striatum (VS) lesions on a two-arm bandit task that had randomly interleaved blocks of stimulus-based and action-based reinforcement learning (RL). Compared with controls, monkeys with VS lesions had deficits in learning to select rewarding images but not rewarding actions. We used a RL model to quantify learning and choice consistency and found that, in stimulus-based RL, the VS lesion monkeys were more influenced by negative feedback and had lower choice consistency than controls. Using a Bayesian model to parse the groups' learning strategies, we also found that VS lesion monkeys defaulted to an action-based choice strategy. Therefore, the VS is involved specifically in learning the value of stimuli, not actions. SIGNIFICANCE STATEMENT Reinforcement learning models of the ventral striatum (VS) often assume that it maintains an estimate of state value. This suggests that it plays a general role in learning whether rewards are assigned based on a chosen action or stimulus. In the present experiment, we examined the effects of VS lesions on monkeys' ability to learn that choosing a particular action or stimulus was more likely to lead to reward. We found that VS lesions caused a specific deficit in the monkeys' ability to discriminate between images with different values, whereas their ability to discriminate between actions with different values remained intact. Our results therefore suggest that the VS plays a specific role in learning to select rewarded stimuli. Copyright © 2017 the authors 0270-6474/17/376902-13$15.00/0.

Detailed Quantitative Classifications of Galaxy Morphology

NASA Astrophysics Data System (ADS)

Nair, Preethi

2018-01-01

Understanding the physical processes responsible for the growth of galaxies is one of the key challenges in extragalactic astronomy. The assembly history of a galaxy is imprinted in a galaxy’s detailed morphology. The bulge-to-total ratio of galaxies, the presence or absence of bars, rings, spiral arms, tidal tails etc, all have implications for the past merger, star formation, and feedback history of a galaxy. However, current quantitative galaxy classification schemes are only useful for broad binning. They cannot classify or exploit the wide variety of galaxy structures seen in nature. Therefore, comparisons of observations with theoretical predictions of secular structure formation have only been conducted on small samples of visually classified galaxies. However large samples are needed to disentangle the complex physical processes of galaxy formation. With the advent of large surveys, like the Sloan Digital Sky Survey (SDSS) and the upcoming Large Synoptic Survey Telescope (LSST) and WFIRST, the problem of statistics will be resolved. However, the need for a robust quantitative classification scheme will still remain. Here I will present early results on promising machine learning algorithms that are providing detailed classifications, identifying bars, rings, multi-armed spiral galaxies, and Hubble type.

Multi-sensor electrometer

NASA Technical Reports Server (NTRS)

Gompf, Raymond (Inventor); Buehler, Martin C. (Inventor)

2003-01-01

An array of triboelectric sensors is used for testing the electrostatic properties of a remote environment. The sensors may be mounted in the heel of a robot arm scoop. To determine the triboelectric properties of a planet surface, the robot arm scoop may be rubbed on the soil of the planet and the triboelectrically developed charge measured. By having an array of sensors, different insulating materials may be measured simultaneously. The insulating materials may be selected so their triboelectric properties cover a desired range. By mounting the sensor on a robot arm scoop, the measurements can be obtained during an unmanned mission.

Work related risk factors for musculoskeletal complaints in the spinning industry in Lithuania

PubMed Central

Gamperiene, M.; Stigum, H.

1999-01-01

OBJECTIVES: To describe the prevalence of self reported musculoskeletal complaints in the back, arms or neck, and legs among workers in the spinning industry, and to investigate the relations between these complaints and work related variables. METHODS: An interview based questionnaire survey was carried out in two spinning industry factories in Lithuania. RESULTS: The study group consisted of all workers in production (n = 363). Symptoms of the legs were the musculoskeletal symptom reported most often (61%). Many subjects had arms or neck (55%) or back problems (28%). 20% had experienced pain from all three sites. Almost 25% had had musculoskeletal pain every day and 16% had experienced constant pain during previous year. Packers had the highest risk of arms or neck problems whereas spinners had the highest risk of back or leg problems. Working in a strained posture (bending, work with arms raised up above shoulder level, and repetitive movements of the fingers) was associated with all three complaints. Only arms or neck complaints were associated with age. CONCLUSIONS: Musculoskeletal disorders are a common problem among workers producing gobelin or synthetic thread in Lithuania and working in a strained posture is a risk factor for developing musculoskeletal disorders in three body sites: legs, arms or neck, and back. To better understand the different aspects of physical load as risk factors, a more detailed study of the frequency of postural changes as well as an observation of individually adopted postures would be necessary. This applies to intervention studies in factories of the spinning industry to prevent complaints of the legs and shoulders.   PMID:10474538

Self-recognition mechanism between skin and suckers prevents octopus arms from interfering with each other.

PubMed

Nesher, Nir; Levy, Guy; Grasso, Frank W; Hochner, Binyamin

2014-06-02

Controlling movements of flexible arms is a challenging task for the octopus because of the virtually infinite number of degrees of freedom (DOFs) [1, 2]. Octopuses simplify this control by using stereotypical motion patterns that reduce the DOFs, in the control space, to a workable few [2]. These movements are triggered by the brain and are generated by motor programs embedded in the peripheral neuromuscular system of the arm [3-5]. The hundreds of suckers along each arm have a tendency to stick to almost any object they contact [6-9]. The existence of this reflex could pose significant problems with unplanned interactions between the arms if not appropriately managed. This problem is likely to be accentuated because it is accepted that octopuses are "not aware of their arms" [10-14]. Here we report of a self-recognition mechanism that has a novel role in motor control, restraining the arms from interfering with each other. We show that the suckers of amputated arms never attach to octopus skin because a chemical in the skin inhibits the attachment reflex of the suckers. The peripheral mechanism appears to be overridden by central control because, in contrast to amputated arms, behaving octopuses sometime grab amputated arms. Surprisingly, octopuses seem to identify their own amputated arms, as they treat arms of other octopuses like food more often than their own. This self-recognition mechanism is a novel peripheral component in the embodied organization of the adaptive interactions between the octopus's brain, body, and environment [15, 16]. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inflation Fossils in Cosmic Structure

NASA Astrophysics Data System (ADS)

Kamionkowski, Marc

The agreement of the predictions of inflation with increasingly precise cosmic microwave background (CMB) and large-scale-structure (LSS) data is remarkable. The notion that such a simple early-Universe scenario, based on still-mysterious ultra-high-energy physics, can explain such a wealth of precise data is simply amazing. An active ongoing program of research is afoot to seek the CMB polarization signatures of inflationary gravitational waves and measure the primordial bispectrum in order to learn about inflation. Still, there is far more that can be done to probe inflationary physics, and no stone should be left unturned in this quest. Here we propose a multi-component program of theoretical research that includes model building, new CMB/LSS tests, a potentially powerful new survey strategy, and the investigation of a new observational avenue for large-scale structure. We propose to broaden the circle of ideas to empirically probe inflation. To begin, the hemispherical power asymmetry seen in WMAP and Planck is truly striking. While it may simply be an unusual statistical fluke, a more tantalizing possibility is that it is a remnant of the pre-inflationary Universe. We propose to develop and study several physical models for this asymmetry and work out other testable predictions of these models. Only by pursuing other signatures of whatever new physics may be responsible for this asymmetry will we be able to infer if it is truly a window to new physics. We also plan to develop departures from statistical isotropy (SI) as a test of inflationary models. We have recently shown that single-field slow-roll inflation generically predicts a quadrupolar departure from SI in primordial perturbations, albeit a very small one. The power quadrupole is expected, however, to be significantly larger in more general inflationary models. We propose to calculate these power quadrupoles so that new constraints to the power quadrupole from CMB and LSS data can be applied to test these models. In a somewhat different vein, we propose to study adaptive strategies for cosmological measurements. Considerable resources are being invested in the ongoing search for B modes in the CMB polarization. This search can be performed on a small patch of sky, but it is optimized by finding the patch of sky that is cleanest of foregrounds. We propose to develop adaptive survey strategies, using lessons learned from the analogous multi-armed bandit problem in probability theory, to optimize B mode searches. Preliminary estimates suggest that such a strategy can improve the sensitivity to primordial gravitational waves by factors of at least 2--3, and possibly much more. We then plan to study the possibility to apply similar strategies to the search for 21-cm fluctuations from the epoch of reionization (EoR) and also to identify an optimal field for a possible JWST deep field survey. Finally, CO intensity mapping has recently been identified as a new and promising probe of the EoR. However, CO intensity mapping may also be used to study large-scale structure at intermediate redshifts (z~1-6) that are important for inflation, dark-energy, and galaxy formation. We propose to calculate angular power spectra of the CO intensity at these redshifts and estimate sensitivities to signals and forecast parameter estimation for various experimental configurations. This work will be essential to guide the development of experiments to seek this signal. In summary, the proposed research will open new avenues to probe the beginning of time with the CMB and LSS, optimize several ongoing measurements, and lay the theoretical groundwork to open a new experimental avenue toward LSS. The proposed research is well aligned with the goals of NASA's Physics of the Cosmos Program. It will provide theoretical support to several current and in-the-pipeline NASA missions and help guide the development of new missions.

Multi-access laser communications transceiver system

NASA Technical Reports Server (NTRS)

Ross, Monte (Inventor); Lokerson, Donald C. (Inventor); Fitzmaurice, Michael W. (Inventor); Meyer, Daniel D. (Inventor)

1993-01-01

A satellite system for optical communications such as a multi-access laser transceiver system. Up to six low Earth orbiting satellites send satellite data to a geosynchronous satellite. The data is relayed to a ground station at the Earth's surface. The earth pointing geosynchronous satellite terminal has no gimbal but has a separate tracking mechanism for tracking each low Earth orbiting satellite. The tracking mechanism has a ring assembly rotatable about an axis coaxial with the axis of the field of view of the geosynchronous satellite and a pivotable arm mounted for pivotal movement on the ring assembly. An optical pickup mechanism at the end of each arm is positioned for optical communication with one of the orbiting satellites by rotation of the ring.

How does a planet excite multiple spiral arms?

NASA Astrophysics Data System (ADS)

Bae, Jaehan; Zhu, Zhaohuan

2018-01-01

Protoplanetary disk simulations show that a single planet excites multiple spiral arms in the background disk, potentially supported by the multi-armed spirals revealed with recent high-resolution observations in some disks. The existence of multiple spiral arms is of importance in many aspects. It is empirically found that the arm-to-arm separation increases as a function of the planetary mass, so one can use the morphology of observed spiral arms to infer the mass of unseen planets. In addition, a spiral arm opens a radial gap as it steepens into a shock, so when a planet excites multiple spiral arms it can open multiple gaps in the disk. Despite the important implications, however, the formation mechanism of multiple spiral arms has not been fully understood by far.In this talk, we explain how a planet excites multiple spiral arms. The gravitational potential of a planet can be decomposed into a Fourier series, a sum of individual azimuthal modes having different azimuthal wavenumbers. Using a linear wave theory, we first demonstrate that appropriate sets of Fourier decomposed waves can be in phase, raising a possibility that constructive interference among the waves can produce coherent structures - spiral arms. More than one spiral arm can form since such constructive interference can occur at different positions in the disk for different sets of waves. We then verify this hypothesis using a suite of two-dimensional hydrodynamic simulations. Finally, we present non-linear behavior in the formation of multiple spiral arms.

Osteosarcoma: the European Osteosarcoma Intergroup (EOI) perspective.

PubMed

Craft, Alan W

2009-01-01

In the late 1970s, there was confusion regarding the best management for osteosarcoma. The benefit of chemotherapy had not been established and which chemotherapy could be used was even more uncertain. The European Osteosarcoma Intergroup (EOI) was established in order to conduct randomised studies to determine the best treatment for this tumour. Their first study 80831 established that a two drug combination of CDDP/DOX was safe and improved the survival rate over previous regimes with suboptimal chemotherapy. The CDDP/DOX was superior to a less intense CDDP/DOX/MTX regime. The second study 80861 compared the CDDP/DOX arm with a multi-drug Rosen-T10 regime. In almost 400 patients, there was the difference in outcome between the two arms. However, adherence to the protocol and completion of allocated treatment was substantially less good in the prolonged 42 week multi-drug regime compared to the two drug arm. The third study 80961 investigated interval compression i.e. if the CDDP/DOX when given every 2 weeks with GCSF superior to the same two drugs given every 3 weeks. There was no difference in survival between the arms, although there was a better histologic response rate in the compressed arm. Three randomised controlled trials on this rare disease have taken more than 20 years to accrue a sufficient sample of patients. The overall outcome has changed little in this time. Large multinational studies are needed to be able to answer these important questions in a timely fashion.

Multi-Hazard Shelter Incentive Programs

DTIC Science & Technology

1985-09-01

by strategic "nuclear missiles. This could pave the way for arms control measures to eliminate the weapons themselves." 9 The following year, the...the idea of a policy change that would emphasize strategic defense. The Arms Control and Disarmament Agency (ACDA), in response to a question from...emergency control centers and program N> management) has been equally divided between the Federal government and the States. Therefore, the rfecedent e

Prediction of Imagined Single-Joint Movements in a Person with High Level Tetraplegia

PubMed Central

Simeral, John D.; Donoghue, John P.; Hochberg, Leigh R.; Kirsch, Robert F.

2013-01-01

Cortical neuroprostheses for movement restoration require developing models for relating neural activity to desired movement. Previous studies have focused on correlating single-unit activities (SUA) in primary motor cortex to volitional arm movements in able-bodied primates. The extent of the cortical information relevant to arm movements remaining in severely paralyzed individuals is largely unknown. We record intracortical signals using a microelectrode array chronically implanted in the precentral gyrus of a person with tetraplegia, and estimate positions of imagined single-joint arm movements. Using visually guided motor imagery, the participant imagined performing eight distinct single-joint arm movements while SUA, multi-spike trains (MSP), multi-unit activity (MUA), and local field potential time (LFPrms) and frequency signals (LFPstft) were recorded. Using linear system identification, imagined joint trajectories were estimated with 20 – 60% variance explained, with wrist flexion/extension predicted the best and pronation/supination the poorest. Statistically, decoding of MSP and LFPstft yielded estimates that equaled those of SUA. Including multiple signal types in a decoder increased prediction accuracy in all cases. We conclude that signals recorded from a single restricted region of the precentral gyrus in this person with tetraplegia contained useful information regarding the intended movements of upper extremity joints. PMID:22851229

Experiences of employees with arm, neck or shoulder complaints: a focus group study

PubMed Central

2014-01-01

Background Many people suffer from complaints of the arm, neck or shoulder (CANS). CANS causes significant work problems, including absenteeism (sickness absence), presenteeism (decreased work productivity) and, ultimately, job loss. There is a need for intervention programs for people suffering from CANS. Management of symptoms and workload, and improving the workstyle, could be important factors in the strategy to deal with CANS. The objective of this study is to evaluate the experienced problems of employees with CANS, as a first step in an intervention mapping process aimed at adaptation of an existing self-management program to the characteristics of employees suffering from CANS. Methods A qualitative study comprising three focus group meetings with 15 employees suffering from CANS. Based on a question guide, participants were asked about experiences in relation to continuing work despite their complaints. Data were analysed using content analysis with an open-coding system. During selective coding, general themes and patterns were identified and relationships between the codes were examined. Results Participants suffering from CANS often have to deal with pain, disability, fatigue, misunderstanding and stress at work. Some needs of the participants were identified, i.e. disease-specific information, exercises, muscle relaxation, working with pain, influence of the work and/or social environment, and personal factors (including workstyle). Conclusions Employees suffering from CANS search for ways to deal with their complaints in daily life and at work. This study reveals several recurring problems and the results endorse the multi-factorial origin of CANS. Participants generally experience problems similar to those of employees with other types of complaints or chronic diseases, e.g. related to their illness, insufficient communication, working together with healthcare professionals, colleagues and management, and workplace adaptations. These topics will be addressed in the adaptation of an existing self-management program to the characteristics of employees suffering from CANS. PMID:24779360

Experiences of employees with arm, neck or shoulder complaints: a focus group study.

PubMed

Hutting, Nathan; Heerkens, Yvonne F; Engels, Josephine A; Staal, J Bart; Nijhuis-van der Sanden, Maria W G

2014-04-29

Many people suffer from complaints of the arm, neck or shoulder (CANS). CANS causes significant work problems, including absenteeism (sickness absence), presenteeism (decreased work productivity) and, ultimately, job loss. There is a need for intervention programs for people suffering from CANS. Management of symptoms and workload, and improving the workstyle, could be important factors in the strategy to deal with CANS. The objective of this study is to evaluate the experienced problems of employees with CANS, as a first step in an intervention mapping process aimed at adaptation of an existing self-management program to the characteristics of employees suffering from CANS. A qualitative study comprising three focus group meetings with 15 employees suffering from CANS. Based on a question guide, participants were asked about experiences in relation to continuing work despite their complaints. Data were analysed using content analysis with an open-coding system. During selective coding, general themes and patterns were identified and relationships between the codes were examined. Participants suffering from CANS often have to deal with pain, disability, fatigue, misunderstanding and stress at work. Some needs of the participants were identified, i.e. disease-specific information, exercises, muscle relaxation, working with pain, influence of the work and/or social environment, and personal factors (including workstyle). Employees suffering from CANS search for ways to deal with their complaints in daily life and at work. This study reveals several recurring problems and the results endorse the multi-factorial origin of CANS. Participants generally experience problems similar to those of employees with other types of complaints or chronic diseases, e.g. related to their illness, insufficient communication, working together with healthcare professionals, colleagues and management, and workplace adaptations. These topics will be addressed in the adaptation of an existing self-management program to the characteristics of employees suffering from CANS.

Evaluation of a New Backtrack Free Path Planning Algorithm for Manipulators

NASA Astrophysics Data System (ADS)

Islam, Md. Nazrul; Tamura, Shinsuke; Murata, Tomonari; Yanase, Tatsuro

This paper evaluates a newly proposed backtrack free path planning algorithm (BFA) for manipulators. BFA is an exact algorithm, i.e. it is resolution complete. Different from existing resolution complete algorithms, its computation time and memory space are proportional to the number of arms. Therefore paths can be calculated within practical and predetermined time even for manipulators with many arms, and it becomes possible to plan complicated motions of multi-arm manipulators in fully automated environments. The performance of BFA is evaluated for 2-dimensional environments while changing the number of arms and obstacle placements. Its performance under locus and attitude constraints is also evaluated. Evaluation results show that the computation volume of the algorithm is almost the same as the theoretical one, i.e. it increases linearly with the number of arms even in complicated environments. Moreover BFA achieves the constant performance independent of environments.

Compact waveguide circular polarizer

DOEpatents

Tantawi, Sami G.

2016-08-16

A multi-port waveguide is provided having a rectangular waveguide that includes a Y-shape structure with first top arm having a first rectangular waveguide port, a second top arm with second rectangular waveguide port, and a base arm with a third rectangular waveguide port for supporting a TE.sub.10 mode and a TE.sub.20 mode, where the end of the third rectangular waveguide port includes rounded edges that are parallel to a z-axis of the waveguide, a circular waveguide having a circular waveguide port for supporting a left hand and a right hand circular polarization TE.sub.11 mode and is coupled to a base arm broad wall, and a matching feature disposed on the base arm broad wall opposite of the circular waveguide for terminating the third rectangular waveguide port, where the first rectangular waveguide port, the second rectangular waveguide port and the circular waveguide port are capable of supporting 4-modes of operation.

Assessment of body composition in dialysis patients by arm bioimpedance compared to MRI and 40K measurements.

PubMed

Carter, M; Zhu, F; Kotanko, P; Kuhlmann, M; Ramirez, L; Heymsfield, S B; Handelman, G; Levin, N W

2009-01-01

This study used multi-frequency bioimpedance spectroscopy (BIS) of the arm and whole body to estimate muscle mass (MM) and subcutaneous adipose tissue (SAT) in 31 hemodialysis (HD) patients comparing these results with magnetic resonance imaging (MRI) and body potassium ((40)K) as gold standards. Total body and arm MM (MM(MRI)) and SAT (SAT(MRI)) were measured by MRI. All measurements were made before dialysis treatment. Regression models with the arm (aBIS) and whole body (wBIS) resistances were established. Correlations between gold standards and the BIS model were high for the arm SAT (r(2) = 0.93, standard error of estimate (SEE) = 3.6 kg), and whole body SAT (r(2) = 0.92, SEE = 3.5 kg), and for arm MM (r(2) = 0.84, SEE = 2.28 kg) and whole body MM (r(2) = 0.86, SEE = 2.28 kg). Total body MM and SAT can be accurately predicted by arm BIS models with advantages of convenience and portability, and it should be useful to assess nutritional status in HD patients. Copyright (c) 2009 S. Karger AG, Basel.

Adaptive Control Strategies for Flexible Robotic Arm

NASA Technical Reports Server (NTRS)

Bialasiewicz, Jan T.

1996-01-01

The control problem of a flexible robotic arm has been investigated. The control strategies that have been developed have a wide application in approaching the general control problem of flexible space structures. The following control strategies have been developed and evaluated: neural self-tuning control algorithm, neural-network-based fuzzy logic control algorithm, and adaptive pole assignment algorithm. All of the above algorithms have been tested through computer simulation. In addition, the hardware implementation of a computer control system that controls the tip position of a flexible arm clamped on a rigid hub mounted directly on the vertical shaft of a dc motor, has been developed. An adaptive pole assignment algorithm has been applied to suppress vibrations of the described physical model of flexible robotic arm and has been successfully tested using this testbed.

Telomere formation on macronuclear chromosomes of Oxytricha trifallax and O. fallax: alternatively processed regions have multiple telomere addition sites

PubMed Central

Williams, Kevin R; Doak, Thomas G; Herrick, Glenn

2002-01-01

Background Ciliates employ massive chromatid breakage and de novo telomere formation during generation of the somatic macronucleus. Positions flanking the 81-MAC locus are reproducibly cut. But those flanking the Common Region are proposed to often escape cutting, generating three nested macronuclear chromosomes, two retaining "arms" still appended to the Common Region. Arm-distal positions must differ (in cis) from the Common Region flanks. Results The Common-Region-flanking positions also differ from the arm-distal positions in that they are "multi-TAS" regions: anchored PCR shows heterogeneous patterns of telomere addition sites, but arm-distal sites do not. The multi-TAS patterns are reproducible, but are sensitive to the sequence of the allele being processed. Thus, random degradation following chromatid cutting does not create this heterogeneity; these telomere addition sites also must be dictated by cis-acting sequences. Conclusions Most ciliates show such micro-heterogeneity in the precise positions of telomere addition sites. Telomerase is believed to be tightly associated with, and act in concert with, the chromatid-cutting nuclease: heterogeneity must be the result of intervening erosion activity. Our "weak-sites" hypothesis explains the correlation between alternative chromatid cutting at the Common Region boundaries and their multi-TAS character: when the chromatid-breakage machine encounters either a weak binding site or a weak cut site at these regions, then telomerase dissociates prematurely, leaving the new end subject to erosion by an exonuclease, which pauses at cis-acting sequences; telomerase eventually heals these resected termini. Finally, we observe TAS positioning influenced by trans-allelic interactions, reminiscent of transvection. PMID:12199911

Predictors of retention and attrition in a study of an advanced upper limb prosthesis: implications for adoption of the DEKA Arm.

PubMed

Resnik, Linda; Cancio, Jill; Klinger, Shana; Latlief, Gail; Sasson, Nicole; Smurr-Walters, Lisa

2018-02-01

The purpose was to identify factors associated with completion of the VA home study of the DEKA Arm. Design and methodological procedures used: Differences between groups were examined using chi-square and t-tests. A multivariable logistic regression model predicting completion was generated and odds ratios (OR) for significant variables calculated. Post-hoc analysis was performed to plot the receiver operating characteristics (ROC) curve. Participants who completed were more likely to be prosthesis users at study onset (p = .03), and less likely to have a history of musculoskeletal problems (p = .047). There were no statistically significant differences between groups who completed and those who did not in gender, race, veteran status, age, body mass index (BMI), weight, height, musculoskeletal pain at baseline, satisfaction with current prosthesis, type of prosthesis, or months of prosthesis use. Two variables, prosthesis use and history of musculoskeletal problems were significant at p < .10. The area under the curve (AUC) accuracy index was 0.78. We considered completion of the home use study a reasonable proxy for participant willingness to adopt the device; and believe that findings can be extrapolated to guide DEKA Arm prescription recommendations. Participants most likely to complete the study were already using a personal prosthesis, and without pre-existing musculoskeletal problems. Implications for rehabilitation Data from the VA Study of the DEKA Arm were analysed to determine which factors were associated with likely successful adoption of the DEKA Arm. Participants most likely to complete the study were those who already using a personal prosthesis, and those without pre-existing chronic or re-occurring musculoskeletal problems. This information may be useful when attempting to identify and target the most appropriate candidates for DEKA Arm prescription.

First experience with particle-in-cell plasma physics code on ARM-based HPC systems

NASA Astrophysics Data System (ADS)

Sáez, Xavier; Soba, Alejandro; Sánchez, Edilberto; Mantsinen, Mervi; Mateo, Sergi; Cela, José M.; Castejón, Francisco

2015-09-01

In this work, we will explore the feasibility of porting a Particle-in-cell code (EUTERPE) to an ARM multi-core platform from the Mont-Blanc project. The used prototype is based on a system-on-chip Samsung Exynos 5 with an integrated GPU. It is the first prototype that could be used for High-Performance Computing (HPC), since it supports double precision and parallel programming languages.

ARM Spacecraft Illustration

NASA Image and Video Library

2016-09-20

This graphic depicts the Asteroid Redirect Vehicle conducting a flyby of its target asteroid. During these flybys, the Asteroid Redirect Mission (ARM) would come within 0.6 miles (1 kilometer), generating imagery with resolution of up to 0.4 of an inch (1 centimeter) per pixel. The robotic segment of ARM will demonstrate advanced, high-power, high-throughput solar electric propulsion; advanced autonomous precision proximity operations at a low-gravity planetary body; and controlled touchdown and liftoff with a multi-ton mass. The crew segment of the mission will include spacewalk activities for sample selection, extraction, containment and return; and mission operations of integrated robotic and crewed vehicle stack -- all key components of future in-space operations for human missions to the Mars system. After collecting a multi-ton boulder from the asteroid, the robotic spacecraft will redirect the boulder to a crew-accessible orbit around the moon, where NASA plans to conduct a series of proving ground missions in the 2020s that will help validate capabilities needed for NASA's Journey to Mars. http://photojournal.jpl.nasa.gov/catalog/PIA21062

Local heterogeneities in cardiac systems suppress turbulence by generating multi-armed rotors

NASA Astrophysics Data System (ADS)

Zhang, Zhihui; Steinbock, Oliver

2016-05-01

Ventricular fibrillation is an extremely dangerous cardiac arrhythmia that is linked to rotating waves of electric activity and chaotically moving vortex lines. These filaments can pin to insulating, cylindrical heterogeneities which swiftly become the new rotation backbone of the local wave field. For thin cylinders, the stabilized rotation is sufficiently fast to repel the free segments of the turbulent filament tangle and annihilate them at the system boundaries. The resulting global wave pattern is periodic and highly ordered. Our cardiac simulations show that also thicker cylinders can establish analogous forms of tachycardia. This process occurs through the spontaneous formation of pinned multi-armed vortices. The observed number of wave arms N depends on the cylinder radius and is associated to stability windows that for N = 2, 3 partially overlap. For N = 1, 2, we find a small gap in which the turbulence is removed but the pinned rotor shows complex temporal dynamics. The relevance of our findings to human cardiology are discussed in the context of vortex pinning to more complex-shaped anatomical features and remodeled myocardium.

Improving lateral resolution and image quality of optical coherence tomography by the multi-frame superresolution technique for 3D tissue imaging

PubMed Central

Shen, Kai; Lu, Hui; Baig, Sarfaraz; Wang, Michael R.

2017-01-01

The multi-frame superresolution technique is introduced to significantly improve the lateral resolution and image quality of spectral domain optical coherence tomography (SD-OCT). Using several sets of low resolution C-scan 3D images with lateral sub-spot-spacing shifts on different sets, the multi-frame superresolution processing of these sets at each depth layer reconstructs a higher resolution and quality lateral image. Layer by layer processing yields an overall high lateral resolution and quality 3D image. In theory, the superresolution processing including deconvolution can solve the diffraction limit, lateral scan density and background noise problems together. In experiment, the improved lateral resolution by ~3 times reaching 7.81 µm and 2.19 µm using sample arm optics of 0.015 and 0.05 numerical aperture respectively as well as doubling the image quality has been confirmed by imaging a known resolution test target. Improved lateral resolution on in vitro skin C-scan images has been demonstrated. For in vivo 3D SD-OCT imaging of human skin, fingerprint and retina layer, we used the multi-modal volume registration method to effectively estimate the lateral image shifts among different C-scans due to random minor unintended live body motion. Further processing of these images generated high lateral resolution 3D images as well as high quality B-scan images of these in vivo tissues. PMID:29188089

Benchmarking GNU Radio Kernels and Multi-Processor Scheduling

DTIC Science & Technology

2013-01-14

AMD E350 APU , comparable to Atom • ARM Cortex A8 running on a Gumstix Overo on an Ettus USRP E110 The general testing procedure consists of • Build...Intel Atom, and the AMD E350 APU . 3.2 Multi-Processor Scheduling Figure 1: GFLOPs per second through an FFT array on an Intel i7. Example output from

Effectiveness of a multicomponent school based intervention to reduce bullying among adolescents in Chandigarh, North India: A quasi-experimental study protocol.

PubMed

Rana, Monica; Gupta, Madhu; Malhi, Prahbhjot; Grover, Sandeep; Kaur, Manmeet

2018-02-05

Bullying perpetration and victimization is associated with significant academic, psychosocial and health related problems among adolescents. There is a need to develop effective interventions to prevent bullying among adolescents, especially in low and middle income countries. This paper presents the study protocol to develop, and evaluate the effect of multi-component school based prevention program for bullying in India. Quasi-experimental study. The study will be conducted among 846 students of grade 7 th and 8 th in the intervention and control schools in Chandigarh, Union Territory, North India. A government and a private school will be selected purposively in each of the intervention and control arm. The intervention is based on socio-ecological model, and will be administered at individual, relationship (parents and teachers) and school level. The primary study outcome will be the proportion of students experiencing any kind of bullying (bullying, victimization, or both), in each study arm. The effectiveness of the intervention will be measured by performing difference in difference analysis and generalized estimating equations. Bullying is an aggressive behaviour with significant morbidities, including psychological or physical trauma, affecting individuals not only in their adolescence, but also later in their adulthood. This quasi-experimental study is expected to provide evidence on whether multi-component bullying prevention intervention program, can reduce the burden of bullying perpetration and victimization among school adolescents in India. The results of the study will add in the exiting literature on bullying intervention program, especially, from the low middle-income countries, as there are limited studies available on this topic in these countries.

Octopuses use a human-like strategy to control precise point-to-point arm movements.

PubMed

Sumbre, Germán; Fiorito, Graziano; Flash, Tamar; Hochner, Binyamin

2006-04-18

One of the key problems in motor control is mastering or reducing the number of degrees of freedom (DOFs) through coordination. This problem is especially prominent with hyper-redundant limbs such as the extremely flexible arm of the octopus. Several strategies for simplifying these control problems have been suggested for human point-to-point arm movements. Despite the evolutionary gap and morphological differences, humans and octopuses evolved similar strategies when fetching food to the mouth. To achieve this precise point-to-point-task, octopus arms generate a quasi-articulated structure based on three dynamic joints. A rotational movement around these joints brings the object to the mouth . Here, we describe a peripheral neural mechanism-two waves of muscle activation propagate toward each other, and their collision point sets the medial-joint location. This is a remarkably simple mechanism for adjusting the length of the segments according to where the object is grasped. Furthermore, similar to certain human arm movements, kinematic invariants were observed at the joint level rather than at the end-effector level, suggesting intrinsic control coordination. The evolutionary convergence to similar geometrical and kinematic features suggests that a kinematically constrained articulated limb controlled at the level of joint space is the optimal solution for precise point-to-point movements.

Kinematics analysis on hinges of robot arm gripper for harmful chemical handling

NASA Astrophysics Data System (ADS)

Razali, Zol Bahri; Kader, Mohamed Mydin M. Abdul; Mustafa, Nurul Fahimah; Daud, Mohd Hisam

2017-09-01

The development of manufacturing industry is booming the application of industrial robot, and proportional to the use of robot arm. Some of the purpose of robot arm gripper is to sort things and place to the proper place. And some of the things are harmful to human, such as harmful chemical. By using robot arm to do picking and placing, it is expected to replace human tasks, as well as to reduce human from the harmful job. The problem of the robot arm gripper, most likely the problem of hinge, thus the analysis on the hinges of robot arm gripper to prevent claw is essential. By using robot arm, instead of human, is labored to do the harmful tasks and unexpected accident happen, costs and expenses in handling injured employee due to the harmful chemicals can be minimized. Thus the objective of this project is to make a kinematics analysis on the hinges of the robot arm gripper. Suitable material such as steel structure has also been selected for the construction of this hinges. This material has properties associated with compressive strength, fire resistance, corrosion and has a shape that is easy to move. Solid Works and ANSYS software is used to create animated movement on the design model and to detect deficiencies in the hinges. Detail methodology is described in this paper.

The Effect of a Multi-Level Intervention on the Initiation of Antiretroviral Therapy (ART) among HIV-Infected Men Who Inject Drugs and Were Diagnosed Late in Thai Nguyen, Vietnam

PubMed Central

Zelaya, Carla E.; Le Minh, Nguyen; Lau, Bryan; Latkin, Carl A.; Viet Ha, Tran; Minh Quan, Vu; Mo, Thi Tran; Sripaipan, Teerada; Davis, Wendy W.; Celentano, David D.; Frangakis, Constantine; Go, Vivian F.

2016-01-01

Background In Vietnam, an estimated 256,000 people are living with HIV, and 58% of HIV-infections reported are among people who inject drugs (PWID). While antiretroviral therapy (ART) is widely available in Vietnam, marginalized hard-to-reach male PWID, demonstrate significantly reduced and delayed access to ART. Methods We investigated the effect of a randomized four-arm multi-level intervention trial on ART initiation among male PWID. Our analysis was conducted among a subset of trial participants (n = 136), who were newly diagnosed as HIV-infected, treatment naïve, and eligible for ART (baseline late diagnosis). The trial arms included: 1, standard of care (HIV testing and counseling); 2, structural-level intervention (door-to-door communications and community video screenings); 3, individual-level intervention (counseling plus group support); and 4, individual-level plus structural-level intervention. In a time-to-event analysis, we used a non-parametric approach for competing risks to estimate cumulative incidence function (CIF) for ART initiation (event of interest) by arm and the difference in CIF for each trial arm as compared to Arm 1. Follow-up was conducted at 6, 12, 18 and 24 months. Data collection occurred from 2009 to 2013. Findings By 24-months, 61.0% initiated ART, and 30.9% had died prior to ART initiation. In the first 6 months, participants in arm 4 (individual plus community intervention) had a 28% (95% confidence interval (CI): 6–50%) increased probability of initiating ART. Despite increasing coverage of ART in all arms throughout follow-up, participants in arm 4 retained a 31% (95% CI: 5–56%) increased probability of initiating ART. The individual and community components of the intervention were only effective when delivered together. Conclusions Marginalized, hard-to-reach men, who do not routinely engage in HIV services, and therefore come into care late, may benefit significantly from both individual counseling and group support, in combination with community-focused stigma reduction, when being referred and attempting to initiate urgently needed ART. PMID:27579772

The Effect of a Multi-Level Intervention on the Initiation of Antiretroviral Therapy (ART) among HIV-Infected Men Who Inject Drugs and Were Diagnosed Late in Thai Nguyen, Vietnam.

PubMed

Zelaya, Carla E; Le Minh, Nguyen; Lau, Bryan; Latkin, Carl A; Viet Ha, Tran; Minh Quan, Vu; Mo, Thi Tran; Sripaipan, Teerada; Davis, Wendy W; Celentano, David D; Frangakis, Constantine; Go, Vivian F

2016-01-01

In Vietnam, an estimated 256,000 people are living with HIV, and 58% of HIV-infections reported are among people who inject drugs (PWID). While antiretroviral therapy (ART) is widely available in Vietnam, marginalized hard-to-reach male PWID, demonstrate significantly reduced and delayed access to ART. We investigated the effect of a randomized four-arm multi-level intervention trial on ART initiation among male PWID. Our analysis was conducted among a subset of trial participants (n = 136), who were newly diagnosed as HIV-infected, treatment naïve, and eligible for ART (baseline late diagnosis). The trial arms included: 1, standard of care (HIV testing and counseling); 2, structural-level intervention (door-to-door communications and community video screenings); 3, individual-level intervention (counseling plus group support); and 4, individual-level plus structural-level intervention. In a time-to-event analysis, we used a non-parametric approach for competing risks to estimate cumulative incidence function (CIF) for ART initiation (event of interest) by arm and the difference in CIF for each trial arm as compared to Arm 1. Follow-up was conducted at 6, 12, 18 and 24 months. Data collection occurred from 2009 to 2013. By 24-months, 61.0% initiated ART, and 30.9% had died prior to ART initiation. In the first 6 months, participants in arm 4 (individual plus community intervention) had a 28% (95% confidence interval (CI): 6-50%) increased probability of initiating ART. Despite increasing coverage of ART in all arms throughout follow-up, participants in arm 4 retained a 31% (95% CI: 5-56%) increased probability of initiating ART. The individual and community components of the intervention were only effective when delivered together. Marginalized, hard-to-reach men, who do not routinely engage in HIV services, and therefore come into care late, may benefit significantly from both individual counseling and group support, in combination with community-focused stigma reduction, when being referred and attempting to initiate urgently needed ART.

Hand/Wrist/Arm Problems

MedlinePlus

... Long-term Abdominal Pain (Stomach Pain), Short-term Ankle Problems Breast Problems in Men Breast Problems in Women Chest Pain in Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea ...

Piracy and Its Impact on the Economy

DTIC Science & Technology

2010-12-01

options to supplement lost income, including 4 Catherine Zara Raymond, “Piracy and Armed Robbery in the Malacca Strait: A Problem...Africa: The Piracy Hot Spot and Its Implications for Global Security,” Mediterranean Quarterly, vol. 20 no. 3 (Summer 2009): 100. 41 Catherine Zara ...43 Catherine Zara Raymond, “Piracy and Armed Robbery in the Malacca Strait: A Problem Solved?” Naval War College Review Vol. 62 No. 3 (Summer

Reachability Maps for In Situ Operations

NASA Technical Reports Server (NTRS)

Deen, Robert G.; Leger, Patrick C.; Robinson, Matthew L.; Bonitz, Robert G.

2013-01-01

This work covers two programs that accomplish the same goal: creation of a "reachability map" from stereo imagery that tells where operators of a robotic arm can reach or touch the surface, and with which instruments. The programs are "marsreach" (for MER) and "phxreach." These programs make use of the planetary image geometry (PIG) library. However, unlike the other programs, they are not multi-mission. Because of the complexity of arm kinematics, the programs are specific to each mission.

Evaluation of force-velocity and power-velocity relationship of arm muscles.

PubMed

Sreckovic, Sreten; Cuk, Ivan; Djuric, Sasa; Nedeljkovic, Aleksandar; Mirkov, Dragan; Jaric, Slobodan

2015-08-01

A number of recent studies have revealed an approximately linear force-velocity (F-V) and, consequently, a parabolic power-velocity (P-V) relationship of multi-joint tasks. However, the measurement characteristics of their parameters have been neglected, particularly those regarding arm muscles, which could be a problem for using the linear F-V model in both research and routine testing. Therefore, the aims of the present study were to evaluate the strength, shape, reliability, and concurrent validity of the F-V relationship of arm muscles. Twelve healthy participants performed maximum bench press throws against loads ranging from 20 to 70 % of their maximum strength, and linear regression model was applied on the obtained range of F and V data. One-repetition maximum bench press and medicine ball throw tests were also conducted. The observed individual F-V relationships were exceptionally strong (r = 0.96-0.99; all P < 0.05) and fairly linear, although it remains unresolved whether a polynomial fit could provide even stronger relationships. The reliability of parameters obtained from the linear F-V regressions proved to be mainly high (ICC > 0.80), while their concurrent validity regarding directly measured F, P, and V ranged from high (for maximum F) to medium-to-low (for maximum P and V). The findings add to the evidence that the linear F-V and, consequently, parabolic P-V models could be used to study the mechanical properties of muscular systems, as well as to design a relatively simple, reliable, and ecologically valid routine test of the muscle ability of force, power, and velocity production.

The Image of Today's Russian Armed Forces in the Eyes of Young People

ERIC Educational Resources Information Center

Novik, V. K.; Perednia, D. G.

2008-01-01

In the recent past there has been animated discussion of problems related to the image of the various social institutions and state organizations of Russia, including the Russian armed forces. Sociological analysis is a constructive way to shed light on the image of the military. The armed forces are linked closely to the main spheres of the life…

Maritime Piracy in the Gulf of Guinea, Regional Challenges and Solutions

DTIC Science & Technology

2012-11-02

December 2002. Annual Report. London, United Kingdom. January 2003 39 Catherine Zara Raymond, “Piracy and Armed Robbery in the Malacca Strait: A...40 Catherine Zara Raymond, “Piracy and Armed Robbery in the Malacca Strait: A Problem Solved?” Naval War...who share common challenges in the same 43 Catherine Zara Raymond, “Piracy and Armed Robbery in

Quick-release connector module

NASA Technical Reports Server (NTRS)

Sedig, Albert R. (Inventor)

1995-01-01

A multi-bay electrical connector is described, of the type that has a frame (12, FIG. 2 ) with cavities (14) that each holds a separate module 20, which enables quick withdrawal of a single module from the frame and its quick replacement. A lock arm (42) is slidable along a first side (50) of a first cavity, and has at least one lock lug (80). A first module has a barrier part (70) that lies inward of the lock lug, which prevents outward movement of the first module out of the frame cavity. The lock arm can be moved to an unlocked position wherein the barrier part on the module lies inward of a gap (84) in the lock arm to permit the module to be pulled out of the frame cavity and later inserted therein. A latch (54) is slidable on the frame in directions (A, B) perpendicular to the sliding movement of the lock arm, and has an abutment (112, FIG. 5 ) that abuts a shoulder (114) on the lock arm to keep the lock arm in its unlocked position until the latch is released.

A novel robotic platform for single-port abdominal surgery

NASA Astrophysics Data System (ADS)

Singh, Satwinder; Cheung, Jo L. K.; Sreedhar, Biji; Hoa, Xuyen Dai; Ng, Hoi Pang; Yeung, Chung Kwong

2018-03-01

In this paper, a novel robot-assisted platform for single-port minimally invasive surgery is presented. A miniaturized seven degrees of freedom (dof) fully internalized in-vivo actuated robotic arm is designed. Due to in-vivo actuation, the system has a smaller footprint and can generate 20 N of gripping force. The complete work envelop of the robotic arms is 252 mm × 192 mm × 322 m. With the assistance of the cannula-swivel system, the robotic arms can also be re-positioned and have multi-quadrant reachability without any additional incision. Surgical tasks, such as lifting, gripping suturing and knot tying that are commonly used in a standard surgical procedure, were performed to verify the dexterity of the robotic arms. A single-port trans-abdominal cholecystectomy in a porcine model was successfully performed to further validate its functionality.

Formalization of the Access Control on ARM-Android Platform with the B Method

NASA Astrophysics Data System (ADS)

Ren, Lu; Wang, Wei; Zhu, Xiaodong; Man, Yujia; Yin, Qing

2018-01-01

ARM-Android is a widespread mobile platform with multi-layer access control mechanisms, security-critical in the system. Many access control vulnerabilities still exist due to the course-grained policy and numerous engineering defects, which have been widely studied. However, few researches focus on the mechanism formalization, including the Android permission framework, kernel process management and hardware isolation. This paper first develops a comprehensive formal access control model on the ARM-Android platform using the B method, from the Android middleware to hardware layer. All the model specifications are type checked and proved to be well-defined, with 75%of proof obligations demonstrated automatically. The results show that the proposed B model is feasible to specify and verify access control schemes in the ARM-Android system, and capable of implementing a practical control module.

Research in computer science

NASA Technical Reports Server (NTRS)

Ortega, J. M.

1986-01-01

Various graduate research activities in the field of computer science are reported. Among the topics discussed are: (1) failure probabilities in multi-version software; (2) Gaussian Elimination on parallel computers; (3) three dimensional Poisson solvers on parallel/vector computers; (4) automated task decomposition for multiple robot arms; (5) multi-color incomplete cholesky conjugate gradient methods on the Cyber 205; and (6) parallel implementation of iterative methods for solving linear equations.

Gambling problems and the impact of family in UK armed forces veterans.

PubMed

Dighton, Glen; Roberts, Elystan; Hoon, Alice E; Dymond, Simon

2018-05-09

Background and aims International evidence indicates elevated problem gambling rates in armed forces veterans compared with the general population. Gambling problems adversely impact one's family, and family-related variables may increase vulnerability to gambling-related harm. Little is known, however, about gambling problems in the United Kingdom (UK) veterans or to what extent family variables, such as parenting history and experience of domestic violence, influence veterans' gambling. Methods We compared veterans (n = 257) and sex- and age-matched controls (n = 514) drawn from the 2007 Adult Psychiatric Morbidity Survey on gambling, financial management, domestic violence, childhood parental presence, and experience of stressful life events. Veterans who left the military before or after 4 years of service were compared. Results Problem gambling was significantly more prevalent in veterans (1.4%) than non-veterans (0.2%), and the impact of gambling problems on the family was specific to male veterans, particularly those who had experienced a traumatic event after the age of 16, and those who were more likely to have been physically attacked by their partner. Overall, this study revealed that the UK armed forces veterans report a higher prevalence rate of problem gambling compared with non-veterans, with potential negative impact on family life.

Daily multi-micronutrient supplementation during tuberculosis treatment increases weight and grip strength among HIV-uninfected but not HIV-infected patients in Mwanza, Tanzania.

PubMed

PrayGod, George; Range, Nyagosya; Faurholt-Jepsen, Daniel; Jeremiah, Kidola; Faurholt-Jepsen, Maria; Aabye, Martine G; Jensen, Lotte; Jensen, Andreas V; Grewal, Harleen M S; Magnussen, Pascal; Changalucha, John; Andersen, Aase Bengaard; Friis, Henrik

2011-04-01

Undernutrition is common among tuberculosis (TB) patients. The objective of this study was to assess the effect of multi-micronutrient supplementation during TB treatment on weight, body composition, and handgrip strength. A total of 865 patients with smear-positive (PTB+) or -negative (PTB-) pulmonary TB were randomly allocated to receive a daily biscuit with or without multi-micronutrients for 60 d during the intensive phase of TB treatment. Weight, arm fat area, arm muscle area, and handgrip strength were assessed at baseline and after 2 and 5 mo. At 2 mo, the multi-micronutrient supplementation led to a higher handgrip gain (1.22 kg; 95% CI = 0.50, 1.94; P = 0.001) but had no effects on other outcomes. The effects of multi-micronutrient supplementation were modified by HIV infection (P-interaction = 0.002). Among HIV- patients, multi-micronutrient supplementation increased weight gain by 590 g (95% CI = -40, 1210; P = 0.07) and handgrip strength by 1.6 kg (95% CI = 0.78, 2.47; P < 0.001), whereas among HIV+ patients, it reduced weight gain by 1440 g (95% CI = 290, 2590; P = 0.002) and had no effect on handgrip strength (0.07 kg; 95% CI = -1.30, 1.46; P = 0.91). The reduced weight gain among HIV+ patients receiving multi-micronutrient supplementation seemed to be explained by a higher proportion of patients reporting fever. At 5 mo, the effects on weight were sustained, whereas there was no effect on handgrip strength. In conclusion, multi-micronutrient supplementation given as a biscuit is beneficial among HIV- PTB patients and may be recommended to TB programs. More research is needed to develop an effective supplement for HIV+ PTB patients.

Coordinated trajectory planning of dual-arm space robot using constrained particle swarm optimization

NASA Astrophysics Data System (ADS)

Wang, Mingming; Luo, Jianjun; Yuan, Jianping; Walter, Ulrich

2018-05-01

Application of the multi-arm space robot will be more effective than single arm especially when the target is tumbling. This paper investigates the application of particle swarm optimization (PSO) strategy to coordinated trajectory planning of the dual-arm space robot in free-floating mode. In order to overcome the dynamics singularities issue, the direct kinematics equations in conjunction with constrained PSO are employed for coordinated trajectory planning of dual-arm space robot. The joint trajectories are parametrized with Bézier curve to simplify the calculation. Constrained PSO scheme with adaptive inertia weight is implemented to find the optimal solution of joint trajectories while specific objectives and imposed constraints are satisfied. The proposed method is not sensitive to the singularity issue due to the application of forward kinematic equations. Simulation results are presented for coordinated trajectory planning of two kinematically redundant manipulators mounted on a free-floating spacecraft and demonstrate the effectiveness of the proposed method.

Beam rider for an Articulated Robot Manipulator (ARM) accurate positioning of long flexible manipulators

NASA Technical Reports Server (NTRS)

Malachowski, M. J.

1990-01-01

Laser beam positioning and beam rider modules were incorporated into the long hollow flexible segment of an articulated robot manipulator (ARM). Using a single laser beam, the system determined the position of the distal ARM endtip, with millimetric precision, in six degrees of freedom, at distances of up to 10 meters. Preliminary designs, using space rated technology for the critical systems, of a two segmented physical ARM, with a single and a dual degree of freedom articulation, were developed, prototyped, and tested. To control the positioning of the physical ARM, an indirect adaptive controller, which used the mismatch between the position of the laser beam under static and dynamic conditions, was devised. To predict the behavior of the system and test the concept, a computer simulation model was constructed. A hierarchical artificially intelligent real time ADA operating system program structure was created. The software was designed for implementation on a dedicated VME bus based Intel 80386 administered parallel processing multi-tasking computer system.

Controlling multiple manipulators using RIPS

NASA Technical Reports Server (NTRS)

Wang, Yulun; Jordan, Steve; Mangaser, Amante; Butner, Steve

1989-01-01

A prototype of the RIPS architecture (Robotic Instruction Processing System) was developed. A two arm robot control experiment is underway to characterize the architecture as well as research multi-arm control. This experiment uses two manipulators to cooperatively position an object. The location of the object is specified by the host computer's mouse. Consequently, real time kinematics and dynamics are necessary. The RIPS architecture is specialized so that it can satisfy these real time constraints. The two arm experimental set-up is discussed. A major part of this work is the continued development of a good programming environment for RIPS. The C++ language is employed and favorable results exist in the targeting of this language to the RIPS hardware.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scribner, R.A.

Sea-launched cruise missiles (SLCMs) present some particularly striking problems for both national security and arms control. These small, dual-purpose, difficult to detect weapons present some formidable challenges for verification in any scheme that attempts to limit rather than eliminate them. Conventionally armed SLCMs offer to the navies of both superpowers important offensive and defensive capabilities. Nuclear armed, long-range, land-attack SLCMs, on the other hand, seem to pose destabilizing threats and otherwise have questionable value, despite strong US support for extensive deployment of them. If these weapons are not constrained, their deployment could circumvent gains which might be made in agreementsmore » directly reducing of strategic nuclear weapons. This paper reviews the technology and planned deployments of SLCMs, the verification schemes which have been discussed and are being investigated to try to deal with the problem, and examines the proposed need for and possible uses of SLCMs. It presents an overview of the problem technically, militarily, and politically.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, P; Bonin, TA; Newman, JF

The Lower Atmospheric Boundary Layer Experiment (LABLE) included two measurement campaigns conducted at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site in Oklahoma during 2012 and 2013. LABLE was designed as a multi-phase, low-cost collaboration among the University of Oklahoma, the National Severe Storms Laboratory, Lawrence Livermore National Laboratory, and the ARM program. A unique aspect was the role of graduate students in LABLE. They served as principal investigators and took the lead in designing and conducting experiments using different sampling strategies to best resolve boundary-layer phenomena.

System integration of pattern recognition, adaptive aided, upper limb prostheses

NASA Technical Reports Server (NTRS)

Lyman, J.; Freedy, A.; Solomonow, M.

1975-01-01

The requirements for successful integration of a computer aided control system for multi degree of freedom artificial arms are discussed. Specifications are established for a system which shares control between a human amputee and an automatic control subsystem. The approach integrates the following subsystems: (1) myoelectric pattern recognition, (2) adaptive computer aiding; (3) local reflex control; (4) prosthetic sensory feedback; and (5) externally energized arm with the functions of prehension, wrist rotation, elbow extension and flexion and humeral rotation.

Flexible sequential designs for multi-arm clinical trials.

PubMed

Magirr, D; Stallard, N; Jaki, T

2014-08-30

Adaptive designs that are based on group-sequential approaches have the benefit of being efficient as stopping boundaries can be found that lead to good operating characteristics with test decisions based solely on sufficient statistics. The drawback of these so called 'pre-planned adaptive' designs is that unexpected design changes are not possible without impacting the error rates. 'Flexible adaptive designs' on the other hand can cope with a large number of contingencies at the cost of reduced efficiency. In this work, we focus on two different approaches for multi-arm multi-stage trials, which are based on group-sequential ideas, and discuss how these 'pre-planned adaptive designs' can be modified to allow for flexibility. We then show how the added flexibility can be used for treatment selection and sample size reassessment and evaluate the impact on the error rates in a simulation study. The results show that an impressive overall procedure can be found by combining a well chosen pre-planned design with an application of the conditional error principle to allow flexible treatment selection. Copyright © 2014 John Wiley & Sons, Ltd.

How Bright are Planet-induced Spiral Arms in Scattered Light?

NASA Astrophysics Data System (ADS)

Dong, Ruobing; Fung, Jeffrey

2017-01-01

Recently, high angular resolution imaging instruments such as SPHERE and GPI have discovered many spiral-arm-like features in near-infrared scattered-light images of protoplanetary disks. Theory and simulations have suggested that these arms are most likely excited by planets forming in the disks; however, a quantitative relation between the arm-to-disk brightness contrast and planet mass is still missing. Using 3D hydrodynamics and radiative transfer simulations, we examine the morphology and contrast of planet-induced arms in disks. We find a power-law relation for the face-on arm contrast (δmax) as a function of planet mass ({M}{{p}}) and disk aspect ratio (h/r): {δ }\\max ≈ {({({M}{{p}}/{M}{{J}})/(h/r)}1.38)}0.22. With current observational capabilities, at a 30 au separation, the minimum planet mass for driving detectable arms in a disk around a 1 Myr, 1 {M}ȯ star at 140 pc at low inclinations is around Saturn mass. For planets more massive than Neptune masses, they typically drive multiple arms. Therefore, in observed disks with spirals, it is unlikely that each spiral arm originates from a different planet. We also find that only massive perturbers with at least multi-Jupiter masses are capable of driving bright arms with {δ }\\max ≳ 2 as found in SAO 206462, MWC 758, and LkHα 330, and these arms do not follow linear wave propagation theory. Additionally, we find that the morphology and contrast of the primary and secondary arms are largely unaffected by a modest level of viscosity with α ≲ 0.01. Finally, the contrast of the arms in the SAO 206462 disk suggests that the perturber SAO 206462 b at ∼100 au is about 5{--}10 {M}{{J}} in mass.

Research on the man in the loop control system of the robot arm based on gesture control

NASA Astrophysics Data System (ADS)

Xiao, Lifeng; Peng, Jinbao

2017-03-01

The Man in the loop control system of the robot arm based on gesture control research complex real-world environment, which requires the operator to continuously control and adjust the remote manipulator, as the background, completes the specific mission human in the loop entire system as the research object. This paper puts forward a kind of robot arm control system of Man in the loop based on gesture control, by robot arm control system based on gesture control and Virtual reality scene feedback to enhance immersion and integration of operator, to make operator really become a part of the whole control loop. This paper expounds how to construct a man in the loop control system of the robot arm based on gesture control. The system is a complex system of human computer cooperative control, but also people in the loop control problem areas. The new system solves the problems that the traditional method has no immersion feeling and the operation lever is unnatural, the adjustment time is long, and the data glove mode wears uncomfortable and the price is expensive.

The flying hot wire and related instrumentation

NASA Technical Reports Server (NTRS)

Coles, D.; Cantnell, B.; Wadcock, A.

1978-01-01

A flying hot-wire technique is proposed for studies of separated turbulent flow in wind tunnels. The technique avoids the problem of signal rectification in regions of high turbulence level by moving the probe rapidly through the flow on the end of a rotating arm. New problems which arise include control of effects of torque variation on rotor speed, avoidance of interference from the wake of the moving arms, and synchronization of data acquisition with rotation. Solutions for these problems are described. The self-calibrating feature of the technique is illustrated by a sample X-array calibration.

Computed torque control of a free-flying cooperat ing-arm robot

NASA Technical Reports Server (NTRS)

Koningstein, Ross; Ullman, Marc; Cannon, Robert H., Jr.

1989-01-01

The unified approach to solving free-floating space robot manipulator end-point control problems is presented using a control formulation based on an extension of computed torque. Once the desired end-point accelerations have been specified, the kinematic equations are used with momentum conservation equations to solve for the joint accelerations in any of the robot's possible configurations: fixed base or free-flying with open/closed chain grasp. The joint accelerations can then be used to calculate the arm control torques and internal forces using a recursive order N algorithm. Initial experimental verification of these techniques has been performed using a laboratory model of a two-armed space robot. This fully autonomous spacecraft system experiences the drag-free, zero G characteristics of space in two dimensions through the use of an air cushion support system. Results of these initial experiments are included which validate the correctness of the proposed methodology. The further problem of control in the large where not only the manipulator tip positions but the entire system consisting of base and arms must be controlled is also presented. The availability of a physical testbed has brought a keener insight into the subtleties of the problem at hand.

Motion and force control of multiple robotic manipulators

NASA Technical Reports Server (NTRS)

Wen, John T.; Kreutz-Delgado, Kenneth

1992-01-01

This paper addresses the motion and force control problem of multiple robot arms manipulating a cooperatively held object. A general control paradigm is introduced which decouples the motion and force control problems. For motion control, different control strategies are constructed based on the variables used as the control input in the controller design. There are three natural choices; acceleration of a generalized coordinate, arm tip force vectors, and the joint torques. The first two choices require full model information but produce simple models for the control design problem. The last choice results in a class of relatively model independent control laws by exploiting the Hamiltonian structure of the open loop system. The motion control only determines the joint torque to within a manifold, due to the multiple-arm kinematic constraint. To resolve the nonuniqueness of the joint torques, two methods are introduced. If the arm and object models are available, an optimization can be performed to best allocate the desired and effector control force to the joint actuators. The other possibility is to control the internal force about some set point. It is shown that effective force regulation can be achieved even if little model information is available.

One-pot synthesis of star-shaped macromolecules containing polyglycidol and poly(ethylene oxide) arms.

PubMed

Lapienis, Grzegorz; Penczek, Stanislaw

2005-01-01

Synthesis of fully hydrophilic star-shaped macromolecules with different kinds of arms (A(x)B(y)C(z)) based on polyglycidol (PGL, A(x)) and poly(ethylene oxide) (PEO, C(z)) arms and diepoxy compounds (diglycidyl ethers of ethylene glycol (DGEG) or neopentyl glycol (DGNG) in the core, B(y)) forming the core is described. Precursors of arms were prepared by polymerization of glycidol with protected -OH groups. The first-generation stars were formed in the series of consecutive-parallel reactions of arms A(x) with diepoxy compounds (B). These first-generation stars (A(x)B(y)), having approximately O-, Mt+ groups on the cores, were used as multianionic initiators for the second generation of arms (C(z)) built by polymerization of ethylene oxide. The products with M(n) up to 10(5) and having up to approximately 40 arms were obtained. The number of arms (f) was determined by direct measurements of M(n) of the first-generation stars (M(n) of arms A(x) is known), compared with f calculated from the branching index g, determined from R(g) measured with size-exclusion chromatography (SEC) triple detection with TriSEC software. The progress of the star formation was monitored by 1H NMR and SEC. These novel water-soluble stars, having a large number of hydroxyl groups, both at the ends of PEO arms as well as within the PGL arms, can be functionalized and further used for attaching compounds of interest. This approach opens, therefore, a new way of "multiPEGylation".

Military Personnel: Joint Officer Development Has Improved, But a Strategic Approach Is Needed. Report to the Subcommittee on Military Personnel, Committee on Armed Services, House of Representatives.

ERIC Educational Resources Information Center

General Accounting Office, Washington, DC.

In response to the need of military leaders to be better prepared to plan, support, and conduct joint (multi-service and multi-national) operations, Congress enacted the Goldwater- Nichols Department of Defense Reorganization Act of 1986. Positive steps were taken to implement provisions in the Act that address the education, assignment, and…

Multi-Service Doctrine for Chemical, Biological, Radiological, and Nuclear Operations

DTIC Science & Technology

2011-07-01

currently valid OMB control number. 1. REPORT DATE JUL 2011 2. REPORT TYPE 3. DATES COVERED 00-00-2011 to 00-00-2011 4. TITLE AND SUBTITLE Multi...research reactors, research and development facilities, laboratories, production facilities, radioisotope thermoelectric generators, pharmaceutical...requests from the U.S. armed forces for emergency, up-to- date medical intelligence assessments. It is the nation’s premier producer and coordinator of

Piracy and Armed Robbery in the Malacca Strait: A Problem Solved

DTIC Science & Technology

2009-01-01

PIRACY AND ARMED ROBBERY IN THE MALACCA STRAIT A Problem Solved? Catherine Zara Raymond The Malacca Strait is a narrow waterway that extends nearly...waterway is extremely small. With statistics such as these, one might wonder why we are still seeing the publication of articles such Catherine Zara Raymond...Shrivenham, United Kingdom. She is also a PhD student at King’s College London. Previ- ously, Zara worked as an analyst for the security consul- tancy

Interphase Chromosome Conformation and Chromatin-chromatin Interactions in Human Epithelial Cells Cultured Under Different Gravity Conditions

NASA Technical Reports Server (NTRS)

Zhang, Ye; Hada, Megumi; Wu, Honglu

2014-01-01

On a multi-mega base pair scale of the DNA, the arrangement of chromatin is non-random. In M10 epithelial cells, both telomere regions tend to be located towards the exterior of the chromosome domain, whereas the rest p-arm of the chromatin region towards the interior. In contrast, most of the q-arm of the chromatin is found in the peripheral of the domain. In lymphocytes, the p-arm chromatin regions towards the interior in close proximity with each other, whereas two q-arm regions are nearness in space. It indicates that G0 lymphocytes may lack secondary 3D chromatin folding. There chromatin folding patterns are consistent with our previous finding of non-random distribution of intra-chromosomal exchanges. In simulated microgravity conditions, the chromosome conformation may be altered and new regions in close proximity, especially to region 2 are suggested.

REVOLUTION IN MILITARY SCIENCE, ITS IMPORTANCE AND CONSEQUENCES, MILITARY ART ON A NEW STAGE,

DTIC Science & Technology

The central problem of modern military art is defined as the development of new methods of conducting armed conflict. The changes involving the radical military technical re-equipping of Soviet Armed Forces, are described.

Movement trajectory smoothness is not associated with the endpoint accuracy of rapid multi-joint arm movements in young and older adults

PubMed Central

Poston, Brach; Van Gemmert, Arend W.A.; Sharma, Siddharth; Chakrabarti, Somesh; Zavaremi, Shahrzad H.; Stelmach, George

2013-01-01

The minimum variance theory proposes that motor commands are corrupted by signal-dependent noise and smooth trajectories with low noise levels are selected to minimize endpoint error and endpoint variability. The purpose of the study was to determine the contribution of trajectory smoothness to the endpoint accuracy and endpoint variability of rapid multi-joint arm movements. Young and older adults performed arm movements (4 blocks of 25 trials) as fast and as accurately as possible to a target with the right (dominant) arm. Endpoint accuracy and endpoint variability along with trajectory smoothness and error were quantified for each block of trials. Endpoint error and endpoint variance were greater in older adults compared with young adults, but decreased at a similar rate with practice for the two age groups. The greater endpoint error and endpoint variance exhibited by older adults were primarily due to impairments in movement extent control and not movement direction control. The normalized jerk was similar for the two age groups, but was not strongly associated with endpoint error or endpoint variance for either group. However, endpoint variance was strongly associated with endpoint error for both the young and older adults. Finally, trajectory error was similar for both groups and was weakly associated with endpoint error for the older adults. The findings are not consistent with the predictions of the minimum variance theory, but support and extend previous observations that movement trajectories and endpoints are planned independently. PMID:23584101

Wideband spectrum analysis of ultra-high frequency radio-wave signals due to advanced one-phonon non-collinear anomalous light scattering.

PubMed

Shcherbakov, Alexandre S; Arellanes, Adan Omar

2017-04-20

We present a principally new acousto-optical cell providing an advanced wideband spectrum analysis of ultra-high frequency radio-wave signals. For the first time, we apply a recently developed approach with the tilt angle to a one-phonon non-collinear anomalous light scattering. In contrast to earlier cases, now one can exploit a regime with the fixed optical wavelength for processing a great number of acoustic frequencies simultaneously in the linear regime. The chosen rutile-crystal combines a moderate acoustic velocity with low acoustic attenuation and allows us wide-band data processing within GHz-frequency acoustic waves. We have created and experimentally tested a 6-cm aperture rutile-made acousto-optical cell providing the central frequency 2.0 GHz, frequency bandwidth ∼0.52  GHz with the frequency resolution about 68.3 kHz, and ∼7620 resolvable spots. A similar cell permits designing an advanced ultra-high-frequency arm within a recently developed multi-band radio-wave acousto-optical spectrometer for astrophysical studies. This spectrometer is intended to operate with a few parallel optical arms for processing the multi-frequency data flows within astrophysical observations. Keeping all the instrument's advantages of the previous schematic arrangement, now one can create the highest-frequency arm using the developed rutile-based acousto-optical cell. It permits optimizing the performances inherent in that arm via regulation of both the central frequency and the frequency bandwidth for spectrum analysis.

Integrated genomics for pinpointing survival loci within arm-level somatic copy number alterations

PubMed Central

Roy, David M.; Walsh, Logan A.; Desrichard, Alexis; Huse, Jason T.; Wu, Wei; Gao, JianJiong; Bose, Promita; Lee, William; Chan, Timothy A.

2016-01-01

SUMMARY The identification of driver loci underlying arm-level somatic copy number alterations (SCNAs) in cancer has remained challenging and incomplete. Here we assess the relative impact and present a detailed landscape of arm-level SCNAs in 10985 patient samples across 33 cancer types from The Cancer Genome Atlas (TCGA). Further, using chromosome 9p loss in lower grade glioma (LGG) as a model, we employ a unique multi-tiered genomic dissection strategy using 540 patients from 3 independent LGG datasets to identify genetic loci that govern tumor aggressiveness and poor survival. This comprehensive approach uncovered several 9p loss-specific prognostic markers, validated existing ones, and re-defined the impact of CDKN2A loss in LGG. PMID:27165745

Development of a bidirectional ring thermal actuator

NASA Astrophysics Data System (ADS)

Stevenson, Mathew; Yang, Peng; Lai, Yongjun; Mechefske, Chris

2007-10-01

A new planar micro electrothermal actuator capable of bidirectional rotation is presented. The ring thermal actuator has a wheel-like geometry with eight arms connecting an outer ring to a central hub. Thermal expansion of the arms results in a rotation of the outer ring about its center. An analytical model is developed for the electrothermal and thermal-mechanical aspects of the actuator's operation. Finite element analysis is used to validate the analytic study. The actuator has been fabricated using the multi-user MEMS process and experimental displacement results are compared with model predictions. Experiments show a possible displacement of 7.4 µm in each direction. Also, by switching the current between the arms it is possible to achieve an oscillating motion.

DC motor proportional control system for orthotic devices

NASA Technical Reports Server (NTRS)

Blaise, H. T.; Allen, J. R.

1972-01-01

Multi-channel proportional control system for operation of dc motors for use with externally-powered orthotic arm braces is described. Components of circuitry and principles of operation are described. Schematic diagram of control circuit is provided.

Gas-liquid flow splitting in T-junction with inclined lateral arm

NASA Astrophysics Data System (ADS)

Yang, Le-le; Liu, Shuo; Li, Hua; Zhang, Jian; Wu, Ying-xiang; Xu, Jing-yu

2018-02-01

This paper studies the gas-liquid flow splitting in T-junction with inclined lateral arm. The separation mechanism of the T-junction is related to the pressure distribution in the T-junction. It is shown that the separation efficiency strongly depends on the inclination angle, when the angle ranges from 0° to 30°, while not so strongly for angles in the range from 30° to 90° Increasing the number of connecting tubes is helpful for the gas-liquid separation, and under the present test conditions, with four connecting tubes, a good separation performance can be achieved. Accordingly, a multi-tube Y-junction separator with four connecting tubes is designed for the experimental investigation. A good agreement between the simulated and measured data shows that there is an optimal split ratio to achieve the best performance for the multi-tube Y-junction separator.

A limit-cycle self-organizing map architecture for stable arm control.

PubMed

Huang, Di-Wei; Gentili, Rodolphe J; Katz, Garrett E; Reggia, James A

2017-01-01

Inspired by the oscillatory nature of cerebral cortex activity, we recently proposed and studied self-organizing maps (SOMs) based on limit cycle neural activity in an attempt to improve the information efficiency and robustness of conventional single-node, single-pattern representations. Here we explore for the first time the use of limit cycle SOMs to build a neural architecture that controls a robotic arm by solving inverse kinematics in reach-and-hold tasks. This multi-map architecture integrates open-loop and closed-loop controls that learn to self-organize oscillatory neural representations and to harness non-fixed-point neural activity even for fixed-point arm reaching tasks. We show through computer simulations that our architecture generalizes well, achieves accurate, fast, and smooth arm movements, and is robust in the face of arm perturbations, map damage, and variations of internal timing parameters controlling the flow of activity. A robotic implementation is evaluated successfully without further training, demonstrating for the first time that limit cycle maps can control a physical robot arm. We conclude that architectures based on limit cycle maps can be organized to function effectively as neural controllers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Healthcare quality improvement -- policy implications and practicalities.

PubMed

Esain, Ann Elizabeth; Williams, Sharon J; Gakhal, Sandeep; Caley, Lynne; Cooke, Matthew W

2012-01-01

This article aims to explore quality improvement (QI) at individual, group and organisational level. It also aims to identify restraining forces using formative evaluation and discuss implications for current UK policy, particularly quality, innovation, productivity and prevention. Learning events combined with work-based projects, focusing on individual and group responses are evaluated. A total of 11 multi-disciplinary groups drawn from NHS England healthcare Trusts (self-governing operational groups) were sampled. These Trusts have different geographic locations and participants were drawn from primary, secondary and commissioning arms. Mixed methods: questionnaires, observations and reflective accounts were used. The paper finds that solution versus problem identification causes confusion and influences success. Time for problem solving to achieve QI was absent. Feedback and learning structures are often not in place or inflexible. Limited focus on patient-centred services may be related to past assumptions regarding organisational design, hence assumptions and models need to be understood and challenged. The authors revise the Plan, Do, Study; Act (PDSA) model by adding an explicit problem identification step and hence avoiding solution-focused habits; demonstrating the need for more formative evaluations to inform managers and policy makers about healthcare QI processes. - Although UK-centric, the quality agenda is a USA and European theme, findings may help those embarking on this journey or those struggling with QI.

From the bench to bedside to babies: translational medicine made possible by funding multidisciplinary team science.

PubMed

Woodruff, Teresa K

2013-10-01

In 2005, The National Institutes of Health (NIH) called upon the scientific community to identify the most intractable problems in science and medicine and describe how we would solve these problems using teams. Our group was one of 8 research communities awarded an 'interdisciplinary research consortium (IRC) grant.' Using the infrastructure of this large, multi-institute grant and a team science approach, we set out to solve the problem of fertility loss in young female cancer patients-work that was not easily funded through other mechanisms. The word 'oncofertility' was coined specifically for the IRC to reflect the intimate partnership between oncology care and fertility care for these patients-two disciplines that would no longer function at arms' length, but as an integrated unit. Catalyzed by the IRC funding mechanism, interdisciplinary teams worked together in unique ways to create a 'bench to bedside to baby' outcome. The grant has now ended, and remarkably, so have the most intractable parts of the original problem. As we look back on what worked and look forward to tackling the next set of fertility-related questions, we are confident that this very special NIH funding mechanism made a meaningful difference in the lives of women and their future children. NIH and the public would be well-served by supporting clinical problem-based, multidisciplinary team science approaches to catalyze fundamental biomedical breakthroughs and create new intellectual environments in which changes in clinical practice and standard of care can be implemented.

A Bayesian pick-the-winner design in a randomized phase II clinical trial.

PubMed

Chen, Dung-Tsa; Huang, Po-Yu; Lin, Hui-Yi; Chiappori, Alberto A; Gabrilovich, Dmitry I; Haura, Eric B; Antonia, Scott J; Gray, Jhanelle E

2017-10-24

Many phase II clinical trials evaluate unique experimental drugs/combinations through multi-arm design to expedite the screening process (early termination of ineffective drugs) and to identify the most effective drug (pick the winner) to warrant a phase III trial. Various statistical approaches have been developed for the pick-the-winner design but have been criticized for lack of objective comparison among the drug agents. We developed a Bayesian pick-the-winner design by integrating a Bayesian posterior probability with Simon two-stage design in a randomized two-arm clinical trial. The Bayesian posterior probability, as the rule to pick the winner, is defined as probability of the response rate in one arm higher than in the other arm. The posterior probability aims to determine the winner when both arms pass the second stage of the Simon two-stage design. When both arms are competitive (i.e., both passing the second stage), the Bayesian posterior probability performs better to correctly identify the winner compared with the Fisher exact test in the simulation study. In comparison to a standard two-arm randomized design, the Bayesian pick-the-winner design has a higher power to determine a clear winner. In application to two studies, the approach is able to perform statistical comparison of two treatment arms and provides a winner probability (Bayesian posterior probability) to statistically justify the winning arm. We developed an integrated design that utilizes Bayesian posterior probability, Simon two-stage design, and randomization into a unique setting. It gives objective comparisons between the arms to determine the winner.

Rewards-driven control of robot arm by decoding EEG signals.

PubMed

Tanwani, Ajay Kumar; del R Millan, Jose; Billard, Aude

2014-01-01

Decoding the user intention from non-invasive EEG signals is a challenging problem. In this paper, we study the feasibility of predicting the goal for controlling the robot arm in self-paced reaching movements, i.e., spontaneous movements that do not require an external cue. Our proposed system continuously estimates the goal throughout a trial starting before the movement onset by online classification and generates optimal trajectories for driving the robot arm to the estimated goal. Experiments using EEG signals of one healthy subject (right arm) yield smooth reaching movements of the simulated 7 degrees of freedom KUKA robot arm in planar center-out reaching task with approximately 80% accuracy of reaching the actual goal.

Design and implementation of self-balancing coaxial two wheel robot based on HSIC

NASA Astrophysics Data System (ADS)

Hu, Tianlian; Zhang, Hua; Dai, Xin; Xia, Xianfeng; Liu, Ran; Qiu, Bo

2007-12-01

This thesis has studied the control problem concerning position and orientation control of self-balancing coaxial two wheel robot based on the human simulated intelligent control (HSIC) theory. Adopting Lagrange equation, the dynamic model of self-balancing coaxial two-wheel Robot is built up, and the Sensory-motor Intelligent Schemas (SMIS) of HSIC controller for the robot is designed by analyzing its movement and simulating the human controller. In robot's motion process, by perceiving position and orientation of the robot and using multi-mode control strategy based on characteristic identification, the HSIC controller enables the robot to control posture. Utilizing Matlab/Simulink, a simulation platform is established and a motion controller is designed and realized based on RT-Linux real-time operating system, employing high speed ARM9 processor S3C2440 as kernel of the motion controller. The effectiveness of the new design is testified by the experiment.

Goal driven kinematic simulation of flexible arm robot for space station missions

NASA Technical Reports Server (NTRS)

Janssen, P.; Choudry, A.

1987-01-01

Flexible arms offer a great degree of flexibility in maneuvering in the space environment. The problem of transporting an astronaut for extra-vehicular activity using a space station based flexible arm robot was studied. Inverse kinematic solutions of the multilink structure were developed. The technique is goal driven and can support decision making for configuration selection as required for stability and obstacle avoidance. Details of this technique and results are given.

A novel Morse code-inspired method for multiclass motor imagery brain-computer interface (BCI) design.

PubMed

Jiang, Jun; Zhou, Zongtan; Yin, Erwei; Yu, Yang; Liu, Yadong; Hu, Dewen

2015-11-01

Motor imagery (MI)-based brain-computer interfaces (BCIs) allow disabled individuals to control external devices voluntarily, helping us to restore lost motor functions. However, the number of control commands available in MI-based BCIs remains limited, limiting the usability of BCI systems in control applications involving multiple degrees of freedom (DOF), such as control of a robot arm. To address this problem, we developed a novel Morse code-inspired method for MI-based BCI design to increase the number of output commands. Using this method, brain activities are modulated by sequences of MI (sMI) tasks, which are constructed by alternately imagining movements of the left or right hand or no motion. The codes of the sMI task was detected from EEG signals and mapped to special commands. According to permutation theory, an sMI task with N-length allows 2 × (2(N)-1) possible commands with the left and right MI tasks under self-paced conditions. To verify its feasibility, the new method was used to construct a six-class BCI system to control the arm of a humanoid robot. Four subjects participated in our experiment and the averaged accuracy of the six-class sMI tasks was 89.4%. The Cohen's kappa coefficient and the throughput of our BCI paradigm are 0.88 ± 0.060 and 23.5bits per minute (bpm), respectively. Furthermore, all of the subjects could operate an actual three-joint robot arm to grasp an object in around 49.1s using our approach. These promising results suggest that the Morse code-inspired method could be used in the design of BCIs for multi-DOF control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dementia Care Management in an Underserved Community: The Comparative Effectiveness of Two Different Approaches.

PubMed

Chodosh, Joshua; Colaiaco, Benjamin A; Connor, Karen Ilene; Cope, Dennis Wesley; Liu, Hangsheng; Ganz, David Avram; Richman, Mark Jason; Cherry, Debra Lynn; Blank, Joseph Moshe; Carbone, Raquel Del Pilar; Wolf, Sheldon Mark; Vickrey, Barbara Grace

2015-08-01

To compare the effectiveness and costs of telephone-only approach to in-person plus telephone for delivering an evidence-based, coordinated care management program for dementia. We randomized 151 patient-caregiver dyads from an underserved predominantly Latino community to two arms that shared a care management protocol but implemented in different formats: in-person visits at home and/or in the community plus telephone and mail, versus telephone and mail only. We compared between-arm caregiver burden and care-recipient problem behaviors (primary outcomes) and patient-caregiver dyad retention, care quality, health care utilization, and costs (secondary outcomes) at 6- and 12-months follow-up. Care quality improved substantially over time in both arms. Caregiver burden, care-recipient problem behaviors, retention, and health care utilization did not differ across arms but the in-person program cost more to deliver. Dementia care quality improved regardless of how care management was delivered; large differences in effectiveness or cost offsets were not detected. © The Author(s) 2015.

Geometric Aspects and Testing of the Galactic Center Distance Determination from Spiral Arm Segments

NASA Astrophysics Data System (ADS)

Nikiforov, I. I.; Veselova, A. V.

2018-02-01

We consider the problem of determining the geometric parameters of a Galactic spiral arm from its segment by including the distance to the spiral pole, i.e., the distance to the Galactic center ( R 0). The question about the number of points belonging to one turn of a logarithmic spiral and defining this spiral as a geometric figure has been investigated numerically and analytically by assuming the direction to the spiral pole (to the Galactic center) to be known. Based on the results obtained, in an effort to test the new approach, we have constructed a simplified method of solving the problem that consists in finding the median of the values for each parameter from all possible triplets of objects in the spiral arm segment satisfying the condition for the angular distance between objects. Applying the method to the data on the spatial distribution of masers in the Perseus and Scutum arms (the catalogue by Reid et al. (2014)) has led to an estimate of R 0 = 8.8 ± 0.5 kpc. The parameters of five spiral arm segments have been determined from masers of the same catalogue. We have confirmed the difference between the spiral arms in pitch angle. The pitch angles of the arms revealed by masers are shown to generally correlate with R 0 in the sense that an increase in R 0 leads to a growth in the absolute values of the pitch angles.

LABLE: A Multi-Institutional, Student-Led, Atmospheric Boundary Layer Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, P.; Bonin, T. A.; Newman, J. F.

This paper presents an overview of the Lower Atmospheric Boundary Layer Experiment (LABLE), which included two measurement campaigns conducted at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site in Oklahoma during 2012 and 2013. LABLE was conducted as a collaborative effort between the University of Oklahoma (OU), the National Severe Storms Laboratory, Lawrence Livermore National Laboratory (LLNL), and the ARM program. LABLE can be considered unique in that it was designed as a multi-phase, low-cost, multi-agency collaboration. Graduate students served as principal investigators and took the lead in designing and conducting experiments aimed at examining boundary-layer processes. The mainmore » objective of LABLE was to study turbulent phenomena in the lowest 2 km of the atmosphere over heterogeneous terrain using a variety of novel atmospheric profiling techniques. Several instruments from OU and LLNL were deployed to augment the suite of in-situ and remote sensing instruments at the ARM site. The complementary nature of the deployed instruments with respect to resolution and height coverage provides a near-complete picture of the dynamic and thermodynamic structure of the atmospheric boundary layer. This paper provides an overview of the experiment including i) instruments deployed, ii) sampling strategies, iii) parameters observed, and iv) student involvement. To illustrate these components, the presented results focus on one particular aspect of LABLE, namely the study of the nocturnal boundary layer and the formation and structure of nocturnal low-level jets. During LABLE, low-level jets were frequently observed and they often interacted with mesoscale atmospheric disturbances such as frontal passages.« less

Phase II trial of temozolomide and sorafenib in advanced melanoma patients with or without brain metastases

PubMed Central

Amaravadi, Ravi K.; Schuchter, Lynn M.; McDermott, David F.; Kramer, Amy; Giles, Lydia; Gramlich, Kristi; Carberry, Mary; Troxel, Andrea B.; Letrero, Richard; Nathanson, Katherine L.; Atkins, Michael B.; O’Dwyer, Peter J.; Flaherty, Keith T.

2009-01-01

Purpose The combination of the oral alkylating agent temozolomide and the oral multi-kinase inhibitor sorafenib was evaluated in advanced melanoma patients. Patients and Methods Patients with metastatic melanoma (N=167) were treated on four arms. All patients received sorafenib at 400 mg orally twice daily without interruption. Patients without brain metastases or prior temozolomide were randomized between Arm A: extended dosing of temozolomide (EDT; 75 mg/m2 temozolomide daily for 6/8 weeks) and Arm B: standard dosing (SDT; 150 mg/m2 temozolomide daily for 5/28 days). Patients previously treated with temozolomide were enrolled on Arm C: EDT. Patients with brain metastases and no prior temozolomide were assigned to Arm D: SDT. The primary endpoint was 6-month progression-free survival (PFS) rate. Secondary endpoints included response rate, toxicity rates, and the rates of BRAF or NRAS mutations. Results The 6-month PFS rate for arms A, B, C, and D were 50%, 40%, 11%, and 23%. The median PFS for patients on arm A, B, C, and D was 5.9, 4.2, 2.2, and 3.5 months, respectively. No significant differences were observed between Arms A and B in 6-month PFS rate, median PFS, or response rates. Treatment was well tolerated in all arms. No significant differences in toxicity were observed between arms A and B except for more grade 3–4 lymphopenia in arm A. Conclusion Temozolomide plus sorafenib was well tolerated and demonstrated activity in melanoma patients without prior history of temozolomide. The activity of this combination regimen warrants further investigation. PMID:19996224

Continuous Evaluation of Fast Processes in Climate Models Using ARM Measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhijin; Sha, Feng; Liu, Yangang

2016-02-02

This five-year award supports the project “Continuous Evaluation of Fast Processes in Climate Models Using ARM Measurements (FASTER)”. The goal of this project is to produce accurate, consistent and comprehensive data sets for initializing both single column models (SCMs) and cloud resolving models (CRMs) using data assimilation. A multi-scale three-dimensional variational data assimilation scheme (MS-3DVAR) has been implemented. This MS-3DVAR system is built on top of WRF/GSI. The Community Gridpoint Statistical Interpolation (GSI) system is an operational data assimilation system at the National Centers for Environmental Prediction (NCEP) and has been implemented in the Weather Research and Forecast (WRF) model.more » This MS-3DVAR is further enhanced by the incorporation of a land surface 3DVAR scheme and a comprehensive aerosol 3DVAR scheme. The data assimilation implementation focuses in the ARM SGP region. ARM measurements are assimilated along with other available satellite and radar data. Reanalyses are then generated for a few selected period of time. This comprehensive data assimilation system has also been employed for other ARM-related applications.« less

Multi-Objectivising Combinatorial Optimisation Problems by Means of Elementary Landscape Decompositions.

PubMed

Ceberio, Josu; Calvo, Borja; Mendiburu, Alexander; Lozano, Jose A

2018-02-15

In the last decade, many works in combinatorial optimisation have shown that, due to the advances in multi-objective optimisation, the algorithms from this field could be used for solving single-objective problems as well. In this sense, a number of papers have proposed multi-objectivising single-objective problems in order to use multi-objective algorithms in their optimisation. In this article, we follow up this idea by presenting a methodology for multi-objectivising combinatorial optimisation problems based on elementary landscape decompositions of their objective function. Under this framework, each of the elementary landscapes obtained from the decomposition is considered as an independent objective function to optimise. In order to illustrate this general methodology, we consider four problems from different domains: the quadratic assignment problem and the linear ordering problem (permutation domain), the 0-1 unconstrained quadratic optimisation problem (binary domain), and the frequency assignment problem (integer domain). We implemented two widely known multi-objective algorithms, NSGA-II and SPEA2, and compared their performance with that of a single-objective GA. The experiments conducted on a large benchmark of instances of the four problems show that the multi-objective algorithms clearly outperform the single-objective approaches. Furthermore, a discussion on the results suggests that the multi-objective space generated by this decomposition enhances the exploration ability, thus permitting NSGA-II and SPEA2 to obtain better results in the majority of the tested instances.

An innovative approach for modeling and simulation of an automated industrial robotic arm operated electro-pneumatically

NASA Astrophysics Data System (ADS)

Popa, L.; Popa, V.

2017-08-01

The article is focused on modeling an automated industrial robotic arm operated electro-pneumatically and to simulate the robotic arm operation. It is used the graphic language FBD (Function Block Diagram) to program the robotic arm on Zelio Logic automation. The innovative modeling and simulation procedures are considered specific problems regarding the development of a new type of technical products in the field of robotics. Thus, were identified new applications of a Programmable Logic Controller (PLC) as a specialized computer performing control functions with a variety of high levels of complexit.

EVA 4 - Massimino with EMS on RMS arm

NASA Image and Video Library

2002-03-07

STS109-323-035 (7 March 2002) --- Astronaut Michael J. Massimino, on the shuttle’s robotic arm, prepares to install the Electronic Support Module (ESM) in the aft shroud of the Hubble Space Telescope (HST), with the assistance of astronaut James H. Newman (out of frame). The module will support a new experimental cooling system to be installed during the next day's fifth and final scheduled spacewalk of the mission. That cooling system is designed to bring the telescope's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) back to life.

Causal analysis of ordinal treatments and binary outcomes under truncation by death.

PubMed

Wang, Linbo; Richardson, Thomas S; Zhou, Xiao-Hua

2017-06-01

It is common that in multi-arm randomized trials, the outcome of interest is "truncated by death," meaning that it is only observed or well-defined conditioning on an intermediate outcome. In this case, in addition to pairwise contrasts, the joint inference for all treatment arms is also of interest. Under a monotonicity assumption we present methods for both pairwise and joint causal analyses of ordinal treatments and binary outcomes in presence of truncation by death. We illustrate via examples the appropriateness of our assumptions in different scientific contexts.

Radiation and Scattering Compact Antenna Laboratory (RASCAL) Capabilities Brochure

DTIC Science & Technology

2016-09-06

Array Measurements Integrated Measurement of Subsystems with Digital Backends RADIATION AND SCATTERING COMPACT ANTENNA LABORATORY...hardware gating to eliminate sources of error within the range itself. Processing is also available for multi-arm spiral antennas for the generation

A multi-faceted tailored strategy to implement an electronic clinical decision support system for pressure ulcer prevention in nursing homes: a two-armed randomized controlled trial.

PubMed

Beeckman, Dimitri; Clays, Els; Van Hecke, Ann; Vanderwee, Katrien; Schoonhoven, Lisette; Verhaeghe, Sofie

2013-04-01

Frail older people admitted to nursing homes are at risk of a range of adverse outcomes, including pressure ulcers. Clinical decision support systems are believed to have the potential to improve care and to change the behaviour of healthcare professionals. To determine whether a multi-faceted tailored strategy to implement an electronic clinical decision support system for pressure ulcer prevention improves adherence to recommendations for pressure ulcer prevention in nursing homes. Two-armed randomized controlled trial in a nursing home setting in Belgium. The trial consisted of a 16-week implementation intervention between February and June 2010, including one baseline, four intermediate, and one post-testing measurement. Primary outcome was the adherence to guideline-based care recommendations (in terms of allocating adequate pressure ulcer prevention in residents at risk). Secondary outcomes were the change in resident outcomes (pressure ulcer prevalence) and intermediate outcomes (knowledge and attitudes of healthcare professionals). Random sample of 11 wards (6 experimental; 5 control) in a convenience sample of 4 nursing homes in Belgium. In total, 464 nursing home residents and 118 healthcare professionals participated. The experimental arm was involved in a multi-faceted tailored implementation intervention of a clinical decision support system, including interactive education, reminders, monitoring, feedback and leadership. The control arm received a hard-copy of the pressure ulcer prevention protocol, supported by standardized 30 min group lecture. Patients in the intervention arm were significantly more likely to receive fully adequate pressure ulcer prevention when seated in a chair (F=16.4, P=0.003). No significant improvement was observed on pressure ulcer prevalence and knowledge of the professionals. While baseline attitude scores were comparable between both groups [exp. 74.3% vs. contr. 74.5% (P=0.92)], the mean score after the intervention was 83.5% in the experimental group vs. 72.1% in the control group (F=15.12, P<0.001). The intervention was only partially successful to improve the primary outcome. Attitudes improved significantly while the knowledge of the healthcare workers remained unsatisfactorily low. Further research should focus on the underlying reasons for these findings. Copyright © 2012 Elsevier Ltd. All rights reserved.

An Analysis of the Impact of American Arms Transfers on Political Stability in Iran.

DTIC Science & Technology

1980-09-01

IMPACT OF AMERICAN ARMS TRANSFERS ON POLITICAL STABILITY IN IRAN by Gregory Francis Gates September 1980 Thesis Advisor: E. J. Laurance Approved for...release; distribution unlimited An Analysis of the Impact of American Arms Transfers on Political Stability in Iran by Gregory Francis Gates Lieutenant...government survived, it is possible these goals may have been met and Iran’s labor problems solved. Unfortunately in 1977-78 when political stability deteriorated

The Geometry of the Arms Race. Applications of Elementary Game Theory to International Relations. Modules and Monographs in Undergraduate Mathematics and Its Applications Project. UMAP Unit 311.

ERIC Educational Resources Information Center

Brams, Steven J.; And Others

This unit views applications of elementary game theory to international relations. It is noted that of all the significant world problems, the nuclear arms race has proved one of the most intractable. The main concern of the module is to investigate a possible solution to the arms race, based on extending the classic two-person game of Prisoner's…

Analyzing octopus movements using three-dimensional reconstruction.

PubMed

Yekutieli, Yoram; Mitelman, Rea; Hochner, Binyamin; Flash, Tamar

2007-09-01

Octopus arms, as well as other muscular hydrostats, are characterized by a very large number of degrees of freedom and a rich motion repertoire. Over the years, several attempts have been made to elucidate the interplay between the biomechanics of these organs and their control systems. Recent developments in electrophysiological recordings from both the arms and brains of behaving octopuses mark significant progress in this direction. The next stage is relating these recordings to the octopus arm movements, which requires an accurate and reliable method of movement description and analysis. Here we describe a semiautomatic computerized system for 3D reconstruction of an octopus arm during motion. It consists of two digital video cameras and a PC computer running custom-made software. The system overcomes the difficulty of extracting the motion of smooth, nonrigid objects in poor viewing conditions. Some of the trouble is explained by the problem of light refraction in recording underwater motion. Here we use both experiments and simulations to analyze the refraction problem and show that accurate reconstruction is possible. We have used this system successfully to reconstruct different types of octopus arm movements, such as reaching and bend initiation movements. Our system is noninvasive and does not require attaching any artificial markers to the octopus arm. It may therefore be of more general use in reconstructing other nonrigid, elongated objects in motion.

The Army’s Armored Multi-Purpose Vehicle (AMPV): Background and Issues for Congress

DTIC Science & Technology

2016-09-14

for Congress Congressional Research Service Summary The Armored Multi-Purpose Vehicle (AMPV) is the Army’s proposed replacement for the Vietnam ...for armor and mechanized infantry units. 1 Known as the M-113, it entered production in 1960 and saw extensive wartime service in Vietnam . Considered...needed to operate as part of combined arms teams within complex operational environments . For example, “commanders will not allow them to leave Forward

Fate and Transport of Tungsten at Camp Edwards Small Arms Ranges

DTIC Science & Technology

2007-08-01

area into the lower berm and/or trough. A similar approach was used in the lower berm area with samples collected from soil sloughing from the...bucket au- ger to collect samples beneath the bullet pockets and the trough. A multi - increment, subsurface soil sample was made by combining the...range. From these soil profiles, a total of 72 multi -increment subsurface soil sam- ples was collected (Table 2). The auger was cleaned between holes

Simultaneous and Continuous Estimation of Shoulder and Elbow Kinematics from Surface EMG Signals

PubMed Central

Zhang, Qin; Liu, Runfeng; Chen, Wenbin; Xiong, Caihua

2017-01-01

In this paper, we present a simultaneous and continuous kinematics estimation method for multiple DoFs across shoulder and elbow joint. Although simultaneous and continuous kinematics estimation from surface electromyography (EMG) is a feasible way to achieve natural and intuitive human-machine interaction, few works investigated multi-DoF estimation across the significant joints of upper limb, shoulder and elbow joints. This paper evaluates the feasibility to estimate 4-DoF kinematics at shoulder and elbow during coordinated arm movements. Considering the potential applications of this method in exoskeleton, prosthetics and other arm rehabilitation techniques, the estimation performance is presented with different muscle activity decomposition and learning strategies. Principle component analysis (PCA) and independent component analysis (ICA) are respectively employed for EMG mode decomposition with artificial neural network (ANN) for learning the electromechanical association. Four joint angles across shoulder and elbow are simultaneously and continuously estimated from EMG in four coordinated arm movements. By using ICA (PCA) and single ANN, the average estimation accuracy 91.12% (90.23%) is obtained in 70-s intra-cross validation and 87.00% (86.30%) is obtained in 2-min inter-cross validation. This result suggests it is feasible and effective to use ICA (PCA) with single ANN for multi-joint kinematics estimation in variant application conditions. PMID:28611573

Modeling and Simulation for Multi-Missions Space Exploration Vehicle

NASA Technical Reports Server (NTRS)

Chang, Max

2011-01-01

Asteroids and Near-Earth Objects [NEOs] are of great interest for future space missions. The Multi-Mission Space Exploration Vehicle [MMSEV] is being considered for future Near Earth Object missions and requires detailed planning and study of its Guidance, Navigation, and Control [GNC]. A possible mission of the MMSEV to a NEO would be to navigate the spacecraft to a stationary orbit with respect to the rotating asteroid and proceed to anchor into the surface of the asteroid with robotic arms. The Dynamics and Real-Time Simulation [DARTS] laboratory develops reusable models and simulations for the design and analysis of missions. In this paper, the development of guidance and anchoring models are presented together with their role in achieving mission objectives and relationships to other parts of the simulation. One important aspect of guidance is in developing methods to represent the evolution of kinematic frames related to the tasks to be achieved by the spacecraft and its robot arms. In this paper, we compare various types of mathematical interpolation methods for position and quaternion frames. Subsequent work will be on analyzing the spacecraft guidance system with different movements of the arms. With the analyzed data, the guidance system can be adjusted to minimize the errors in performing precision maneuvers.

Rational geometrical engineering of palladium sulfide multi-arm nanostructures as a superior bi-functional electrocatalyst.

PubMed

Nandan, R; Nanda, K K

2017-08-31

Geometrical tunability offers sharp edges and an open-armed structure accompanied with a high electrochemical active surface area to ensure the efficient and effective utilization of materials by exposing the electrochemical active sites for facile accessibility of reactant species. Herein, we report a one-step, single-pot, surfactant-free, electroless, and economic route to synthesize palladium sulfide nanostructures with different geometries at mild temperatures and their catalytic properties towards the oxygen reduction reaction (ORR) and methanol electro-oxidation (MOR). For ORR, the positive on-set, half wave potentials, smaller Tafel slope, high electrochemical active surface area, large roughness factor, and better cyclic stability of the proposed nanostructures as compared to those of the commercial state-of-the-art Pt-C/PdS catalysts suggest their superiority in an alkaline medium. In addition, high mass activity (J f ∼ 715 mA mg -1 ), in comparison with that of the commercial state-of-the-art Pt-C/PdS catalysts (J f ∼ 138/41 mA mg -1 , respectively), and high J f /J b (1.52) along with the superior operational stability of the multi-arm palladium sulfide nanostructures towards MOR advocates the bi-functional behavior of the catalyst and its potential as a promising Pt-free anode/cathode electrocatalyst in fuel cells.

New Linear and Star-Shaped Thermogelling Poly([R]-3-hydroxybutyrate) Copolymers.

PubMed

Barouti, Ghislaine; Liow, Sing Shy; Dou, Qingqing; Ye, Hongye; Orione, Clément; Guillaume, Sophie M; Loh, Xian Jun

2016-07-18

The synthesis of multi-arm poly([R]-3-hydroxybutyrate) (PHB)-based triblock copolymers (poly([R]-3-hydroxybutyrate)-b-poly(N-isopropylacrylamide)-b-[[poly(methyl ether methacrylate)-g-poly(ethylene glycol)]-co-[poly(methacrylate)-g-poly(propylene glycol)

Claiming lesbian history: the romance between fact and fiction.

PubMed

Garber, Linda

2015-01-01

The contested field of lesbian history exists along a continuum, with undisputed evidence on one end and informed speculation on the other. Lesbian historical fiction extends the spectrum, envisioning the lives of lesbian pirates, war heroes, pioneers, bandits, and stock romantic characters, as well as the handful of protagonists examined here whose quests specifically highlight the difficulty and importance of researching the lesbian past. The genre blossomed in the 1980s, just as the Foucauldian insistence that homosexual identity did not exist before the late nineteenth century gained sway in the academy. The proliferation of lesbian historical fictions signals the growing desire for more thorough (if not completely factual) historical underpinnings of the burgeoning lesbian identities, communities, and politics set in motion in the 1970s.

Self-perpetuating Spiral Arms in Disk Galaxies

NASA Astrophysics Data System (ADS)

D'Onghia, Elena; Vogelsberger, Mark; Hernquist, Lars

2013-03-01

The causes of spiral structure in galaxies remain uncertain. Leaving aside the grand bisymmetric spirals with their own well-known complications, here we consider the possibility that multi-armed spiral features originate from density inhomogeneities orbiting within disks. Using high-resolution N-body simulations, we follow the motions of stars under the influence of gravity, and show that mass concentrations with properties similar to those of giant molecular clouds can induce the development of spiral arms through a process termed swing amplification. However, unlike in earlier work, we demonstrate that the eventual response of the disk can be highly non-linear, significantly modifying the formation and longevity of the resulting patterns. Contrary to expectations, ragged spiral structures can thus survive at least in a statistical sense long after the original perturbing influence has been removed.

HOW TO PASS ARMED FORCES TESTS.

ERIC Educational Resources Information Center

Cowles Education Corp., New York, NY.

FOLLOWING THE CONTENT OF THE ARMED FORCES EXAMINATIONS, THIS BOOK IS PROGRAMED WITH STEP-BY-STEP DIRECTIONS, TESTS, AND CORRECT ANSWERS AND SOLUTIONS. THE CANDIDATE CAN SIMULATE TAKING THE ACTUAL EXAMS BY ANSWERING THE AUTHENTIC QUESTIONS AND PROBLEMS, MARKING THE ANSWER SHEET, AND EVALUATING HIS OWN APTITUDE BY COMPARING HIS ANSWERS WITH THE…

Quantitative analysis of arm movement smoothness

NASA Astrophysics Data System (ADS)

Szczesna, Agnieszka; Błaszczyszyn, Monika

2017-07-01

The paper deals with the problem of motion data quantitative smoothness analysis. We investigated values of movement unit, fluidity and jerk for healthy and paralyzed arm of patients with hemiparesis after stroke. Patients were performing drinking task. To validate the approach, movement of 24 patients were captured using optical motion capture system.

THE DYNAMICS OF SPIRAL ARMS IN PURE STELLAR DISKS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujii, M. S.; Baba, J.; Saitoh, T. R.

2011-04-01

It has been believed that spiral arms in pure stellar disks, especially the ones spontaneously formed, decay in several galactic rotations due to the increase of stellar velocity dispersions. Therefore, some cooling mechanism, for example dissipational effects of the interstellar medium, was assumed to be necessary to keep the spiral arms. Here, we show that stellar disks can maintain spiral features for several tens of rotations without the help of cooling, using a series of high-resolution three-dimensional N-body simulations of pure stellar disks. We found that if the number of particles is sufficiently large, e.g., 3 x 10{sup 6}, multi-armmore » spirals developed in an isolated disk can survive for more than 10 Gyr. We confirmed that there is a self-regulating mechanism that maintains the amplitude of the spiral arms. Spiral arms increase Toomre's Q of the disk, and the heating rate correlates with the squared amplitude of the spirals. Since the amplitude itself is limited by Q, this makes the dynamical heating less effective in the later phase of evolution. A simple analytical argument suggests that the heating is caused by gravitational scattering of stars by spiral arms and that the self-regulating mechanism in pure stellar disks can effectively maintain spiral arms on a cosmological timescale. In the case of a smaller number of particles, e.g., 3 x 10{sup 5}, spiral arms grow faster in the beginning of the simulation (while Q is small) and they cause a rapid increase of Q. As a result, the spiral arms become faint in several Gyr.« less

Trial of Early Aggressive Therapy in Polyarticular Juvenile Idiopathic Arthritis

PubMed Central

Wallace, Carol A.; Giannini, Edward H.; Spalding, Steven J.; Hashkes, Philip J.; O’Neil, Kathleen M.; Zeft, Andrew S.; Szer, Ilona S.; Ringold, Sarah; Brunner, Hermine I.; Schanberg, Laura E.; Sundel, Robert P.; Milojevic, Diana; Punaro, Marilynn G.; Chira, Peter; Gottlieb, Beth S.; Higgins, Gloria C.; Ilowite, Norman T.; Kimura, Yukiko; Hamilton, Stephanie; Johnson, Anne; Huang, Bin; Lovell, Daniel J.

2011-01-01

OBJECTIVES To determine if aggressive treatment initiated early in the course of rheumatoid factor positive or negative polyarticular juvenile idiopathic arthritis (poly-JIA) can induce clinical inactive disease (CID) within 6 months. METHODS Between May 2007 and October 2010 a multi-center, prospective, double blind, randomized, placebo controlled trial of two aggressive treatments was conducted in 85 children aged 2 to 16 years with polyarticular JIA of less than 12 months duration. Patients received either methotrexate 0.5 mg/kg/wk SQ (40 mg max), etanercept 0.8 mg/kg/wk (50 mg max), prednisolone 0.5 mg/kg/d (60 mg max) tapered to 0 by 17 weeks (Arm 1), or methotrexate (same dose as Arm 1), etanercept placebo, and prednisolone placebo (Arm 2). The primary outcome was CID at 6 months. An exploratory phase determined the rate of clinical remission on medication (6 months of continuous CID) at 12 months. RESULTS By 6 months, 17 of 42 (40%) of patients in Arm 1 and 10 of 43 (23%) in Arm 2 had achieved CID (X2 = 2.91; p = 0.088). After 12 months, 9 patients in Arm 1 and 3 in Arm 2 achieved clinical remission on medication (p = 0.0534). There were no significant inter-arm differences in adverse events. CONCLUSIONS Although this study did not meet its primary endpoint, early aggressive therapy in this cohort of children with recent onset polyarticular JIA resulted in substantial proportions of patients in both arms achieving CID by 6 months and clinical remission on medication within 12 months of treatment. PMID:22183975

Design of a multi-arm randomized clinical trial with no control arm.

PubMed

Magaret, Amalia; Angus, Derek C; Adhikari, Neill K J; Banura, Patrick; Kissoon, Niranjan; Lawler, James V; Jacob, Shevin T

2016-01-01

Clinical trial designs that include multiple treatments are currently limited to those that perform pairwise comparisons of each investigational treatment to a single control. However, there are settings, such as the recent Ebola outbreak, in which no treatment has been demonstrated to be effective; and therefore, no standard of care exists which would serve as an appropriate control. For illustrative purposes, we focused on the care of patients presenting in austere settings with critically ill 'sepsis-like' syndromes. Our approach involves a novel algorithm for comparing mortality among arms without requiring a single fixed control. The algorithm allows poorly-performing arms to be dropped during interim analyses. Consequently, the study may be completed earlier than planned. We used simulation to determine operating characteristics for the trial and to estimate the required sample size. We present a potential study design targeting a minimal effect size of a 23% relative reduction in mortality between any pair of arms. Using estimated power and spurious significance rates from the simulated scenarios, we show that such a trial would require 2550 participants. Over a range of scenarios, our study has 80 to 99% power to select the optimal treatment. Using a fixed control design, if the control arm is least efficacious, 640 subjects would be enrolled into the least efficacious arm, while our algorithm would enroll between 170 and 430. This simulation method can be easily extended to other settings or other binary outcomes. Early dropping of arms is efficient and ethical when conducting clinical trials with multiple arms. Copyright © 2015 Elsevier Inc. All rights reserved.

Unifying Temporal and Structural Credit Assignment Problems

NASA Technical Reports Server (NTRS)

Agogino, Adrian K.; Tumer, Kagan

2004-01-01

Single-agent reinforcement learners in time-extended domains and multi-agent systems share a common dilemma known as the credit assignment problem. Multi-agent systems have the structural credit assignment problem of determining the contributions of a particular agent to a common task. Instead, time-extended single-agent systems have the temporal credit assignment problem of determining the contribution of a particular action to the quality of the full sequence of actions. Traditionally these two problems are considered different and are handled in separate ways. In this article we show how these two forms of the credit assignment problem are equivalent. In this unified frame-work, a single-agent Markov decision process can be broken down into a single-time-step multi-agent process. Furthermore we show that Monte-Carlo estimation or Q-learning (depending on whether the values of resulting actions in the episode are known at the time of learning) are equivalent to different agent utility functions in a multi-agent system. This equivalence shows how an often neglected issue in multi-agent systems is equivalent to a well-known deficiency in multi-time-step learning and lays the basis for solving time-extended multi-agent problems, where both credit assignment problems are present.

Clues to the Formation of Spiral Structure in M51 from the Ages and Locations of Star Clusters

NASA Astrophysics Data System (ADS)

Chandar, Rupali; Chien, L.-H.; Meidt, Sharon; Querejeta, Miguel; Dobbs, Clare; Schinnerer, Eva; Whitmore, Bradley C.; Calzetti, Daniela; Dinino, Daiana; Kennicutt, Robert C.; Regan, Michael

2017-08-01

We determine the spatial distributions of star clusters at different ages in the grand-design spiral galaxy M51 using a new catalog based on multi-band images taken with the Hubble Space Telescope (HST). These distributions, when compared with the spiral structure defined by molecular gas, dust, young and old stars, show the following sequence in the inner arms: dense molecular gas (and dust) defines the inner edge of the spiral structure, followed by an overdensity of old stars and then young stellar clusters. The offset between gas and young clusters in the inner arms is consistent with the expectations for a density wave. Clusters as old as a few hundred Myr remain concentrated close to the spiral arms, although the distributions are broader than those for the youngest clusters, which is also consistent with predictions from density wave simulations. The outermost portion of the west arm is different from the rest of the spiral structure in that it contains primarily intermediate-age (≈ 100{--}400 {Myr}) clusters; we believe that this is a “material” arm. We have identified four “feathers,” stellar structures beyond the inner arms that have a larger pitch angle than the arms. We do not find age gradients along any of the feathers, but the least coherent feathers appear to have the largest range of cluster ages.

Cloud Size Distributions from Multi-sensor Observations of Shallow Cumulus Clouds

NASA Astrophysics Data System (ADS)

Kleiss, J.; Riley, E.; Kassianov, E.; Long, C. N.; Riihimaki, L.; Berg, L. K.

2017-12-01

Combined radar-lidar observations have been used for almost two decades to document temporal changes of shallow cumulus clouds at the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Facility's Southern Great Plains (SGP) site in Oklahoma, USA. Since the ARM zenith-pointed radars and lidars have a narrow field-of-view (FOV), the documented cloud statistics, such as distributions of cloud chord length (or horizontal length scale), represent only a slice along the wind direction of a region surrounding the SGP site, and thus may not be representative for this region. To investigate this impact, we compare cloud statistics obtained from wide-FOV sky images collected by ground-based observations at the SGP site to those from the narrow FOV active sensors. The main wide-FOV cloud statistics considered are cloud area distributions of shallow cumulus clouds, which are frequently required to evaluate model performance, such as routine large eddy simulation (LES) currently being conducted by the ARM LASSO (LES ARM Symbiotic Simulation and Observation) project. We obtain complementary macrophysical properties of shallow cumulus clouds, such as cloud chord length, base height and thickness, from the combined radar-lidar observations. To better understand the broader observational context where these narrow FOV cloud statistics occur, we compare them to collocated and coincident cloud area distributions from wide-FOV sky images and high-resolution satellite images. We discuss the comparison results and illustrate the possibility to generate a long-term climatology of cloud size distributions from multi-sensor observations at the SGP site.

The RAndomized Placebo Phase Study Of Rilonacept in the Treatment of Systemic Juvenile Idiopathic Arthritis (RAPPORT)

PubMed Central

Ilowite, Norman T.; Prather, Kristi; Lokhnygina, Yuliya; Schanberg, Laura E.; Elder, Melissa; Milojevic, Diana; Verbsky, James W.; Spalding, Steven J.; Kimura, Yukiko; Imundo, Lisa F.; Punaro, Marilynn G.; Sherry, David D.; Tarvin, Stacey E.; Zemel, Lawrence S.; Birmingham, James D.; Gottlieb, Beth S.; Miller, Michael L.; O'Neil, Kathleen; Ruth, Natasha M.; Wallace, Carol A.; Singer, Nora G.; Sandborg, Christy I.

2015-01-01

Background Interleukin-1 plays a pivotal role in in the pathogenesis of systemic juvenile idiopathic arthritis (sJIA). We assessed the efficacy and safety of rilonacept (IL-1 trap), an IL-1 inhibitor, in a randomized, double-blind, placebo-controlled trial. Methods An initial 4-week double-blind placebo phase was incorporated into a 24-week randomized multi-center design, followed by an open label phase. We randomized 71 children with at least 2 active joints 1:1 to 2 arms of the study. Patients in the rilonacept arm received rilonacept (4.4mg/kg loading dose followed by 2.2mg/kg weekly, subcutaneously) from day 0; patients in the placebo arm received placebo for 4 weeks followed by a loading dose of rilonacept at week 4 followed by weekly maintenance doses. The primary endpoint was time to response, using adapted JIA ACR30 response criteria coupled with absence of fever and taper of systemic corticosteroids using pre-specified criteria. Results Time to response was shorter in the rilonacept arm than in the placebo arm (Chi-square 7.235, P=.007). Secondary analysis showed 20/35 (57%) of patients in the rilonacept arm responded at week 4 compared to 9/33 (27%) in the placebo arm (P=.016) using the same response criteria. Exacerbation of sJIA (4) was the most common SAE. More patients in the rilonacept arm had elevated liver transaminases, including more than three times the upper limits of normal, as compared to those in the placebo arm. Adverse events were similar in the two arms of the study. Conclusions Rilonacept was generally well tolerated and demonstrated efficacy in active sJIA. PMID:24839206

Screened selection design for randomised phase II oncology trials: an example in chronic lymphocytic leukaemia

PubMed Central

2013-01-01

Background As there are limited patients for chronic lymphocytic leukaemia trials, it is important that statistical methodologies in Phase II efficiently select regimens for subsequent evaluation in larger-scale Phase III trials. Methods We propose the screened selection design (SSD), which is a practical multi-stage, randomised Phase II design for two experimental arms. Activity is first evaluated by applying Simon’s two-stage design (1989) on each arm. If both are active, the play-the-winner selection strategy proposed by Simon, Wittes and Ellenberg (SWE) (1985) is applied to select the superior arm. A variant of the design, Modified SSD, also allows the arm with the higher response rates to be recommended only if its activity rate is greater by a clinically-relevant value. The operating characteristics are explored via a simulation study and compared to a Bayesian Selection approach. Results Simulations showed that with the proposed SSD, it is possible to retain the sample size as required in SWE and obtain similar probabilities of selecting the correct superior arm of at least 90%; with the additional attractive benefit of reducing the probability of selecting ineffective arms. This approach is comparable to a Bayesian Selection Strategy. The Modified SSD performs substantially better than the other designs in selecting neither arm if the underlying rates for both arms are desirable but equivalent, allowing for other factors to be considered in the decision making process. Though its probability of correctly selecting a superior arm might be reduced, it still performs reasonably well. It also reduces the probability of selecting an inferior arm. Conclusions SSD provides an easy to implement randomised Phase II design that selects the most promising treatment that has shown sufficient evidence of activity, with available R codes to evaluate its operating characteristics. PMID:23819695

Screened selection design for randomised phase II oncology trials: an example in chronic lymphocytic leukaemia.

PubMed

Yap, Christina; Pettitt, Andrew; Billingham, Lucinda

2013-07-03

As there are limited patients for chronic lymphocytic leukaemia trials, it is important that statistical methodologies in Phase II efficiently select regimens for subsequent evaluation in larger-scale Phase III trials. We propose the screened selection design (SSD), which is a practical multi-stage, randomised Phase II design for two experimental arms. Activity is first evaluated by applying Simon's two-stage design (1989) on each arm. If both are active, the play-the-winner selection strategy proposed by Simon, Wittes and Ellenberg (SWE) (1985) is applied to select the superior arm. A variant of the design, Modified SSD, also allows the arm with the higher response rates to be recommended only if its activity rate is greater by a clinically-relevant value. The operating characteristics are explored via a simulation study and compared to a Bayesian Selection approach. Simulations showed that with the proposed SSD, it is possible to retain the sample size as required in SWE and obtain similar probabilities of selecting the correct superior arm of at least 90%; with the additional attractive benefit of reducing the probability of selecting ineffective arms. This approach is comparable to a Bayesian Selection Strategy. The Modified SSD performs substantially better than the other designs in selecting neither arm if the underlying rates for both arms are desirable but equivalent, allowing for other factors to be considered in the decision making process. Though its probability of correctly selecting a superior arm might be reduced, it still performs reasonably well. It also reduces the probability of selecting an inferior arm. SSD provides an easy to implement randomised Phase II design that selects the most promising treatment that has shown sufficient evidence of activity, with available R codes to evaluate its operating characteristics.

Effectiveness Evaluation Method of Anti-Radiation Missile against Active Decoy

NASA Astrophysics Data System (ADS)

Tang, Junyao; Cao, Fei; Li, Sijia

2017-06-01

In the problem of anti-radiation missile against active decoy, whether the ARM can effectively kill the target radiation source and bait is an important index for evaluating the operational effectiveness of the missile. Aiming at this problem, this paper proposes a method to evaluate the effect of ARM against active decoy. Based on the calculation of ARM’s ability to resist the decoy, the paper proposes a method to evaluate the decoy resistance based on the key components of the hitting radar. The method has the advantages of scientific and reliability.

Auxiliary principle technique and iterative algorithm for a perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems.

PubMed

Rahaman, Mijanur; Pang, Chin-Tzong; Ishtyak, Mohd; Ahmad, Rais

2017-01-01

In this article, we introduce a perturbed system of generalized mixed quasi-equilibrium-like problems involving multi-valued mappings in Hilbert spaces. To calculate the approximate solutions of the perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems, firstly we develop a perturbed system of auxiliary generalized multi-valued mixed quasi-equilibrium-like problems, and then by using the celebrated Fan-KKM technique, we establish the existence and uniqueness of solutions of the perturbed system of auxiliary generalized multi-valued mixed quasi-equilibrium-like problems. By deploying an auxiliary principle technique and an existence result, we formulate an iterative algorithm for solving the perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems. Lastly, we study the strong convergence analysis of the proposed iterative sequences under monotonicity and some mild conditions. These results are new and generalize some known results in this field.

Solving multi-objective optimization problems in conservation with the reference point method

PubMed Central

Dujardin, Yann; Chadès, Iadine

2018-01-01

Managing the biodiversity extinction crisis requires wise decision-making processes able to account for the limited resources available. In most decision problems in conservation biology, several conflicting objectives have to be taken into account. Most methods used in conservation either provide suboptimal solutions or use strong assumptions about the decision-maker’s preferences. Our paper reviews some of the existing approaches to solve multi-objective decision problems and presents new multi-objective linear programming formulations of two multi-objective optimization problems in conservation, allowing the use of a reference point approach. Reference point approaches solve multi-objective optimization problems by interactively representing the preferences of the decision-maker with a point in the criteria (objectives) space, called the reference point. We modelled and solved the following two problems in conservation: a dynamic multi-species management problem under uncertainty and a spatial allocation resource management problem. Results show that the reference point method outperforms classic methods while illustrating the use of an interactive methodology for solving combinatorial problems with multiple objectives. The method is general and can be adapted to a wide range of ecological combinatorial problems. PMID:29293650

Effects of star-shape poly(alkyl methacrylate) arm uniformity on lubricant properties

DOE PAGES

Robinson, Joshua W.; Qu, Jun; Erck, Robert; ...

2016-03-29

Star-shaped poly(alkyl methacrylate)s (PAMAs) were prepared and blended into an additive-free engine oil to assess the structure property relationship between macromolecular structure and lubricant performance. These additives were designed with a comparable number of repeating units per arm and the number of arms was varied between 3 and 6. Well-defined star-shaped PAMAs were synthesized by atom transfer radical polymerization (ATRP) via a core-first strategy from multi-functional headgroups. Observations of the polymer-oil blends suggest that stars with less than four arms are favorable as a viscosity index improver (VII), and molecular weight dominates viscosity-related effects over other structural features. Star-shaped PAMAs,more » as oil additives, effectively reduce the friction coefficient in both mixed and boundary lubrication regime. Several analogs outperformed commercial VIIs in both viscosity and friction performance. Furthermore, increased wear rates were observed for these star-shaped PAMAs in the boundary lubrication regime suggesting pressure-sensitive conformations may exist.« less

Multi-arm multilateral haptics-based immersive tele-robotic system (HITS) for improvised explosive device disposal

NASA Astrophysics Data System (ADS)

Erickson, David; Lacheray, Hervé; Lai, Gilbert; Haddadi, Amir

2014-06-01

This paper presents the latest advancements of the Haptics-based Immersive Tele-robotic System (HITS) project, a next generation Improvised Explosive Device (IED) disposal (IEDD) robotic interface containing an immersive telepresence environment for a remotely-controlled three-articulated-robotic-arm system. While the haptic feedback enhances the operator's perception of the remote environment, a third teleoperated dexterous arm, equipped with multiple vision sensors and cameras, provides stereo vision with proper visual cues, and a 3D photo-realistic model of the potential IED. This decentralized system combines various capabilities including stable and scaled motion, singularity avoidance, cross-coupled hybrid control, active collision detection and avoidance, compliance control and constrained motion to provide a safe and intuitive control environment for the operators. Experimental results and validation of the current system are presented through various essential IEDD tasks. This project demonstrates that a two-armed anthropomorphic Explosive Ordnance Disposal (EOD) robot interface can achieve complex neutralization techniques against realistic IEDs without the operator approaching at any time.

VizieR Online Data Catalog: Southern H II Region Discovery Survey: pilot survey (Brown+, 2017)

NASA Astrophysics Data System (ADS)

Brown, C.; Jordan, C.; Dickey, J. M.; Anderson, L. D.; Armentrout, W. P.; Balser, D. S.; Bania, T. M.; Dawson, J. R.; Mc Clure-Griffiths, N. M.; Wenger, T. V.

2018-05-01

The Southern H II Region Discovery Survey (SHRDS) is a multi-year project using the Australia Telescope Compact Array (ATCA) to complement the GBT and Arecibo HRDS by extending the survey area into the southern sky (δ<-45°). This area includes the Southern end of the Galactic Bar, the Near and Far 3 kpc Arms, the Norma/Cygnus Arm, the Scutum/Crux Arm, the Sagitttarius/Carina Arm, and outside the solar circle, the Perseus Arm, and the Outer Arm. All pilot SHRDS observations used the ATCA in the five antenna H75 array configuration, giving a nominal maximum baseline of 75 m and a beam size of FWHM ~65" at 7.8 GHz depending on the declination and hour angles of the observations. The SHRDS pilot observations were done in two sessions. Epoch I, observed 2013 June 30, focused on candidates that were expected to show bright radio recombination line (RRL) detections, which they did. Epoch II, observed 2014 June 26 and 27, used a list of candidates with expected flux densities typical of the SHRDS catalog as a whole. The two epochs also used different longitude ranges in order to generate samples of H II regions with different Galactic radii. (3 data files).

The International Traffic in Arms Regulations: An Impediment to National Security

DTIC Science & Technology

2008-05-02

00-00-2007 to 00-00-2008 4. TITLE AND SUBTITLE The International Traffic in Arms Regulations: An Impediment to National Security 5a . CONTRACT...2008 2. REPORT TYPE Program Research Paper 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a . CONTRACT NUMBER The International Traffic in Arms...certain level of ITAR problems, such as on Koreasat 5 with its dual civil and military uses, U.S. companies will often choose not to expend the bid and

Evolving Arms Transfer Rationales: The Case of Italy

DTIC Science & Technology

1987-06-01

began to 5 Libro Bianco-La Difesa, 1977, 57-92. 6 1bid. 23 reconstitute and reequip her armed forces. The 1950’s were tumultuous for the activity in...discussion of the early arms trade in Italy. 8 La Difesa-- Libro Bianco, Ministero della Difesa d’Italia, 1985. 74. 24 in recognizing the problem, the... Libro Bianco, p.xiv. This quote is a portion of the introduction to the White Book written by the Minister of Defense, Giovanni Spadolini. 31 however

Two arm robot path planning in a static environment using polytopes and string stretching. Thesis

NASA Technical Reports Server (NTRS)

Schima, Francis J., III

1990-01-01

The two arm robot path planning problem has been analyzed and reduced into components to be simplified. This thesis examines one component in which two Puma-560 robot arms are simultaneously holding a single object. The problem is to find a path between two points around obstacles which is relatively fast and minimizes the distance. The thesis involves creating a structure on which to form an advanced path planning algorithm which could ideally find the optimum path. An actual path planning method is implemented which is simple though effective in most common situations. Given the limits of computer technology, a 'good' path is currently found. Objects in the workspace are modeled with polytopes. These are used because they can be used for rapid collision detection and still provide a representation which is adequate for path planning.

Structural Design Considerations for a 50 kW-Class Solar Array for NASA's Asteroid Redirect Mission

NASA Technical Reports Server (NTRS)

Kerslake, Thomas W.; Kraft, Thomas G.; Yim, John T.; Le, Dzu K.

2016-01-01

NASA is planning an Asteroid Redirect Mission (ARM) to take place in the 2020s. To enable this multi-year mission, a 40 kW class solar electric propulsion (SEP) system powered by an advanced 50 kW class solar array will be required. Powered by the SEP module (SEPM), the ARM vehicle will travel to a large near-Earth asteroid, descend to its surface, capture a multi-metric ton (t) asteroid boulder, ascend from the surface and return to the Earth-moon system to ultimately place the ARM vehicle and its captured asteroid boulder into a stable distant orbit. During the years that follow, astronauts flying in the Orion multipurpose crew vehicle (MPCV) will dock with the ARM vehicle and conduct extra-vehicular activity (EVA) operations to explore and sample the asteroid boulder. This paper will review the top structural design considerations to successfully implement this 50 kW class solar array that must meet unprecedented performance levels. These considerations include beyond state-of-the-art metrics for specific mass, specific volume, deployed area, deployed solar array wing (SAW) keep in zone (KIZ), deployed strength and deployed frequency. Analytical and design results are presented that support definition of stowed KIZ and launch restraint interface definition. An offset boom is defined to meet the deployed SAW KIZ. The resulting parametric impact of the offset boom length on spacecraft moment of inertias and deployed SAW quasistatic and dynamic load cases are also presented. Load cases include ARM spacecraft thruster plume impingement, asteroid surface operations and Orion docking operations which drive the required SAW deployed strength and damping. The authors conclude that to support NASA's ARM power needs, an advanced SAW is required with mass performance better than 125 W/kg, stowed volume better than 40 kW/cu m, a deployed area of 200 sq m (100 sq m for each of two SAWs), a deployed SAW offset distance of nominally 3-4 m, a deployed SAW quasistatic strength of nominally 0.1 g in any direction, a deployed loading displacement under 2 m, a deployed fundamental frequency above 0.1 Hz and deployed damping of at least 1%. These parameters must be met on top of challenging mission environments and ground testing requirements unique to the ARM project.

Control and applications of cooperating disparate robotic manipulators relevant to nuclear waste management

NASA Technical Reports Server (NTRS)

Lew, Jae Young; Book, Wayne J.

1991-01-01

Remote handling in nuclear waste management requires a robotic system with precise motion as well as a large workspace. The concept of a small arm mounted on the end of a large arm may satisfy such needs. However, the performance of such a serial configuration lacks payload capacity which is a crucial factor for handling a massive object. Also, this configuration induces more flexibility on the structure. To overcome these problems, the topology of bracing the tip of the small arm (not the large arm) and having an end effector in the middle of the chain is proposed in this paper. Also, control of these cooperating disparate manipulators is accomplished in computer simulations. Thus, this robotic system can have the accuracy of the small arm, and at the same time, it can have the payload capacity and large workspace of the large arm.

Reprogramming the articulated robotic arm for glass handling by using Arduino microcontroller

NASA Astrophysics Data System (ADS)

Razali, Zol Bahri; Kader, Mohamed Mydin M. Abdul; Kadir, Mohd Asmadi Akmal; Daud, Mohd Hisam

2017-09-01

The application of articulated robotic arm in industries is raised due to the expansion of using robot to replace human task, especially for the harmful tasks. However a few problems happen with the program use to schedule the arm, Thus the purpose of this project is to design, fabricate and integrate an articulated robotic arm by using Arduino microcontroller for handling glass sorting system. This project was designed to segregate glass and non-glass waste which would be pioneer step for recycling. This robotic arm has four servo motors to operate as a whole; three for the body and one for holding mechanism. This intelligent system is controlled by Arduino microcontroller and build with optical sensor to provide the distinguish objects that will be handled. Solidworks model was used to produce the detail design of the robotic arm and make the mechanical properties analysis by using a CAD software.

Demonstration of the Attributes of Multi-increment Sampling and Proper Sample Processing Protocols for the Characterization of Metals on DoD Facilities

DTIC Science & Technology

2013-06-01

lenses of unconsolidated sand and rounded river gravel overlain by as much as 5 m of silt. Gravel consists mostly of quartz and metamorphic rock with...iii LIST OF FIGURES Page Figure 1. Example of multi-increment sampling using a systematic-random sampling design for collecting two separate...The small arms firing Range 16 Record berms at Fort Wainwright. .................... 25 Figure 9. Location of berms sampled using ISM and grab

Preconception maternal nutrition: a multi-site randomized controlled trial

PubMed Central

2014-01-01

Background Research directed to optimizing maternal nutrition commencing prior to conception remains very limited, despite suggestive evidence of its importance in addition to ensuring an optimal nutrition environment in the periconceptional period and throughout the first trimester of pregnancy. Methods/Study design This is an individually randomized controlled trial of the impact on birth length (primary outcome) of the time at which a maternal nutrition intervention is commenced: Arm 1: ≥ 3 mo preconception vs. Arm 2: 12-14 wk gestation vs. Arm 3: none. 192 (derived from 480) randomized mothers and living offspring in each arm in each of four research sites (Guatemala, India, Pakistan, Democratic Republic of the Congo). The intervention is a daily 20 g lipid-based (118 kcal) multi-micronutient (MMN) supplement. Women randomized to receive this intervention with body mass index (BMI) <20 or whose gestational weight gain is low will receive an additional 300 kcal/d as a balanced energy-protein supplement. Researchers will visit homes biweekly to deliver intervention and monitor compliance, pregnancy status and morbidity; ensure prenatal and delivery care; and promote breast feeding. The primary outcome is birth length. Secondary outcomes include: fetal length at 12 and 34 wk; incidence of low birth weight (LBW); neonatal/infant anthropometry 0-6 mo of age; infectious disease morbidity; maternal, fetal, newborn, and infant epigenetics; maternal and infant nutritional status; maternal and infant microbiome; gut inflammatory biomarkers and bioactive and nutritive compounds in breast milk. The primary analysis will compare birth Length-for-Age Z-score (LAZ) among trial arms (independently for each site, estimated effect size: 0.35). Additional statistical analyses will examine the secondary outcomes and a pooled analysis of data from all sites. Discussion Positive results of this trial will support a paradigm shift in attention to nutrition of all females of child-bearing age. Trial registration ClinicalTrials.gov NCT01883193. PMID:24650219

Multi-arm group sequential designs with a simultaneous stopping rule.

PubMed

Urach, S; Posch, M

2016-12-30

Multi-arm group sequential clinical trials are efficient designs to compare multiple treatments to a control. They allow one to test for treatment effects already in interim analyses and can have a lower average sample number than fixed sample designs. Their operating characteristics depend on the stopping rule: We consider simultaneous stopping, where the whole trial is stopped as soon as for any of the arms the null hypothesis of no treatment effect can be rejected, and separate stopping, where only recruitment to arms for which a significant treatment effect could be demonstrated is stopped, but the other arms are continued. For both stopping rules, the family-wise error rate can be controlled by the closed testing procedure applied to group sequential tests of intersection and elementary hypotheses. The group sequential boundaries for the separate stopping rule also control the family-wise error rate if the simultaneous stopping rule is applied. However, we show that for the simultaneous stopping rule, one can apply improved, less conservative stopping boundaries for local tests of elementary hypotheses. We derive corresponding improved Pocock and O'Brien type boundaries as well as optimized boundaries to maximize the power or average sample number and investigate the operating characteristics and small sample properties of the resulting designs. To control the power to reject at least one null hypothesis, the simultaneous stopping rule requires a lower average sample number than the separate stopping rule. This comes at the cost of a lower power to reject all null hypotheses. Some of this loss in power can be regained by applying the improved stopping boundaries for the simultaneous stopping rule. The procedures are illustrated with clinical trials in systemic sclerosis and narcolepsy. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Satellite Estimates of Surface Short-wave Fluxes: Issues of Implementation

NASA Technical Reports Server (NTRS)

Wang, H.; Pinker, Rachel; Minnis, Patrick

2006-01-01

Surface solar radiation reaching the Earth's surface is the primary forcing function of the land surface energy and water cycle. Therefore, there is a need for information on this parameter, preferably, at global scale. Satellite based estimates are now available at accuracies that meet the demands of many scientific objectives. Selection of an approach to estimate such fluxes requires consideration of trade-offs between the use of multi-spectral observations of cloud optical properties that are more difficult to implement at large scales, and methods that are simplified but easier to implement. In this study, an evaluation of such trade-offs will be performed. The University of Maryland Surface Radiation Model (UMD/SRB) has been used to reprocess five years of GOES-8 satellite observations over the United States to ensure updated calibration and improved cloud detection over snow. The UMD/SRB model was subsequently modified to allow input of information on aerosol and cloud optical depth with information from independent satellite sources. Specifically, the cloud properties from the Atmospheric Radiation Measurement (ARM) Satellite Data Analysis Program (Minnis et al., 1995) are used to drive the modified version of the model to estimate surface short-wave fluxes over the Southern Great Plain ARM sites for a twelve month period. The auxiliary data needed as model inputs such as aerosol optical depth, spectral surface albedo, water vapor and total column ozone amount were kept the same for both versions of the model. The estimated shortwave fluxes are evaluated against ground observations at the ARM Central Facility and four satellite ARM sites. During summer, the estimated fluxes based on cloud properties derived from the multi-spectral approach were in better agreement with ground measurements than those derived from the UMD/SRB model. However, in winter, the fluxes derived with the UMD/SRB model were in better agreement with ground observations than those estimated from cloud properties provided by the ARM Satellite Data Analysis Program. During the transition periods, the results were comparable.

Acceptance test report (MI-74067-009-00). SVWS access arm (Serial number AA-09-03) (drawing 75M08129-13)

NASA Technical Reports Server (NTRS)

Hagood, J. T.

1973-01-01

Acceptance tests were conducted at Kennedy Space Center of the Saturn Vehicle Workshop Spacecraft Access Arm and related equipment. The tests were conducted to prove complete system capability to operate satisfactorily under conditions required to support spacecraft operations and activities. The SVWS Access Arm, serial number AA-09-03, is a Command Module Service Arm, S/A 9, which was removed from the mobile launcher and modified to support the SVWS operations. The C/M environmental chamber was removed and a completely new chamber was installed. The retract system was redesigned to remove the automatic/remote control capability and replaced with a local manual control. The SVWS Access Arm System was successfully tested and supported spacecraft processing without major problems.

Development of a dual joystick-controlled laser trapping and cutting system for optical micromanipulation of chromosomes inside living cells.

PubMed

Harsono, Marcellinus S; Zhu, Qingyuan; Shi, Linda Z; Duquette, Michelle; Berns, Michael W

2013-02-01

A multi-joystick robotic laser microscope system used to control two optical traps (tweezers) and one laser scissors has been developed for subcellular organelle manipulation. The use of joysticks has provided a "user-friendly" method for both trapping and cutting of organelles such as chromosomes in live cells. This innovative design has enabled the clean severing of chromosome arms using the laser scissors as well as the ability to easily hold and pull the severed arm using the laser tweezers. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

NASA's Asteroid Redirect Mission (ARM)

NASA Technical Reports Server (NTRS)

Abell, P. A.; Mazanek, D. D.; Reeves, D. M.; Chodas, P. W.; Gates, M. M.; Johnson, L. N.; Ticker, R. L.

2017-01-01

Mission Description and Objectives: NASA's Asteroid Redirect Mission (ARM) consists of two mission segments: 1) the Asteroid Redirect Robotic Mission (ARRM), a robotic mission to visit a large (greater than approximately 100 meters diameter) near-Earth asteroid (NEA), collect a multi-ton boulder from its surface along with regolith samples, and return the asteroidal material to a stable orbit around the Moon; and 2) the Asteroid Redirect Crewed Mission (ARCM), in which astronauts will explore and investigate the boulder and return to Earth with samples. The ARRM is currently planned to launch at the end of 2021 and the ARCM is scheduled for late 2026.

Cooperative Mmonitoring Center Occasional Paper/5: Propspects of Conventional Arms Control in South Asia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupta, Amit; Kamal, Nazir

1998-11-01

The intensely adversarial relationship between India and Pakistan is marked by military rivalry, mutual distrust, and suspicion. The most dividing disagreement has been over the Kashmir region. An inability to discuss the Kashmir issue has prevented discussion on other important issues. Since there is little prospect of detente, at least in the near-term, the question is whether this rivalry can be contained by other means, such as arms control approaches. Conventional arms control has been applied flexibly and successfully in some regions to reduce threat-perceptions and achieve reassuring military stability. Some lessons from other international models might be applied tomore » the India/Pakistan context. This paper discusses the status of conventional arms control in South Asia, the dominant Indian and Pakistani perceptions about arms control, the benefits that could be derived from arms control, as well as the problems and prospects of arms control. It also discusses existing conventional arms control agreements at the regional and global levels as well as the potential role of cooperative monitoring technology.« less

Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: a multi-institutional phase II randomised clinical trial.

PubMed

Pollock, Sean; O'Brien, Ricky; Makhija, Kuldeep; Hegi-Johnson, Fiona; Ludbrook, Jane; Rezo, Angela; Tse, Regina; Eade, Thomas; Yeghiaian-Alvandi, Roland; Gebski, Val; Keall, Paul J

2015-07-18

There is a clear link between irregular breathing and errors in medical imaging and radiation treatment. The audiovisual biofeedback system is an advanced form of respiratory guidance that has previously demonstrated to facilitate regular patient breathing. The clinical benefits of audiovisual biofeedback will be investigated in an upcoming multi-institutional, randomised, and stratified clinical trial recruiting a total of 75 lung cancer patients undergoing radiation therapy. To comprehensively perform a clinical evaluation of the audiovisual biofeedback system, a multi-institutional study will be performed. Our methodological framework will be based on the widely used Technology Acceptance Model, which gives qualitative scales for two specific variables, perceived usefulness and perceived ease of use, which are fundamental determinants for user acceptance. A total of 75 lung cancer patients will be recruited across seven radiation oncology departments across Australia. Patients will be randomised in a 2:1 ratio, with 2/3 of the patients being recruited into the intervention arm and 1/3 in the control arm. 2:1 randomisation is appropriate as within the interventional arm there is a screening procedure where only patients whose breathing is more regular with audiovisual biofeedback will continue to use this system for their imaging and treatment procedures. Patients within the intervention arm whose free breathing is more regular than audiovisual biofeedback in the screen procedure will remain in the intervention arm of the study but their imaging and treatment procedures will be performed without audiovisual biofeedback. Patients will also be stratified by treating institution and for treatment intent (palliative vs. radical) to ensure similar balance in the arms across the sites. Patients and hospital staff operating the audiovisual biofeedback system will complete questionnaires to assess their experience with audiovisual biofeedback. The objectives of this clinical trial is to assess the impact of audiovisual biofeedback on breathing motion, the patient experience and clinical confidence in the system, clinical workflow, treatment margins, and toxicity outcomes. This clinical trial marks an important milestone in breathing guidance studies as it will be the first randomised, controlled trial providing the most comprehensive evaluation of the clinical impact of breathing guidance on cancer radiation therapy to date. This study is powered to determine the impact of AV biofeedback on breathing regularity and medical image quality. Objectives such as determining the indications and contra-indications for the use of AV biofeedback, evaluation of patient experience, radiation toxicity occurrence and severity, and clinician confidence will shed light on the design of future phase III clinical trials. This trial has been registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), its trial ID is ACTRN12613001177741 .

Neck Injuries and Disorders

MedlinePlus

... tendons, ligaments, or nerves - can cause neck problems. Neck pain is very common. Pain may also come from ... upper arms. Muscle strain or tension often causes neck pain. The problem is usually overuse, such as from ...

Nearly automatic motion capture system for tracking octopus arm movements in 3D space.

PubMed

Zelman, Ido; Galun, Meirav; Akselrod-Ballin, Ayelet; Yekutieli, Yoram; Hochner, Binyamin; Flash, Tamar

2009-08-30

Tracking animal movements in 3D space is an essential part of many biomechanical studies. The most popular technique for human motion capture uses markers placed on the skin which are tracked by a dedicated system. However, this technique may be inadequate for tracking animal movements, especially when it is impossible to attach markers to the animal's body either because of its size or shape or because of the environment in which the animal performs its movements. Attaching markers to an animal's body may also alter its behavior. Here we present a nearly automatic markerless motion capture system that overcomes these problems and successfully tracks octopus arm movements in 3D space. The system is based on three successive tracking and processing stages. The first stage uses a recently presented segmentation algorithm to detect the movement in a pair of video sequences recorded by two calibrated cameras. In the second stage, the results of the first stage are processed to produce 2D skeletal representations of the moving arm. Finally, the 2D skeletons are used to reconstruct the octopus arm movement as a sequence of 3D curves varying in time. Motion tracking, segmentation and reconstruction are especially difficult problems in the case of octopus arm movements because of the deformable, non-rigid structure of the octopus arm and the underwater environment in which it moves. Our successful results suggest that the motion-tracking system presented here may be used for tracking other elongated objects.

Robotics technology discipline

NASA Technical Reports Server (NTRS)

Montemerlo, Melvin D.

1990-01-01

Viewgraphs on robotics technology discipline for Space Station Freedom are presented. Topics covered include: mechanisms; sensors; systems engineering processes for integrated robotics; man/machine cooperative control; 3D-real-time machine perception; multiple arm redundancy control; manipulator control from a movable base; multi-agent reasoning; and surfacing evolution technologies.

Bathymetry and Geology of the Floor of Yellowstone Lake, Yellowstone National Park, Wyoming, Idaho, and Montana

USGS Publications Warehouse

Morgan, L.A.; Shanks, Wayne C.; Lee, G.K.; Webring, M.W.

2007-01-01

High-resolution, multi-beam sonar mapping of Yellowstone Lake was conducted by the U.S. Geological Survey in conjunction with the National Park Service from 1999 to 2002. Yellowstone Lake is the largest high-altitude lake in North America, at an altitude of 2,357 m with a surface area of 341 km2. More than 140 rivers and streams flow into Yellowstone Lake. The Yellowstone River, which enters at the southern end of the lake into the Southeast Arm, dominates the inflow of water and sediment (Shanks and others, 2005). The only outlet from the lake is at Fishing Bridge where the Yellowstone River flows northward discharging 375 to 4,600 cubic feet per second. The multi-beam sonar mapping occurred over a four-year period beginning in 1999 with mapping of the northern basin, continued in 2000 in West Thumb basin, in 2001 in the central basin, and in 2002 in the southern part of the lake including the Flat Mountain, South, and Southeast Arms.

Improved multi-objective ant colony optimization algorithm and its application in complex reasoning

NASA Astrophysics Data System (ADS)

Wang, Xinqing; Zhao, Yang; Wang, Dong; Zhu, Huijie; Zhang, Qing

2013-09-01

The problem of fault reasoning has aroused great concern in scientific and engineering fields. However, fault investigation and reasoning of complex system is not a simple reasoning decision-making problem. It has become a typical multi-constraint and multi-objective reticulate optimization decision-making problem under many influencing factors and constraints. So far, little research has been carried out in this field. This paper transforms the fault reasoning problem of complex system into a paths-searching problem starting from known symptoms to fault causes. Three optimization objectives are considered simultaneously: maximum probability of average fault, maximum average importance, and minimum average complexity of test. Under the constraints of both known symptoms and the causal relationship among different components, a multi-objective optimization mathematical model is set up, taking minimizing cost of fault reasoning as the target function. Since the problem is non-deterministic polynomial-hard(NP-hard), a modified multi-objective ant colony algorithm is proposed, in which a reachability matrix is set up to constrain the feasible search nodes of the ants and a new pseudo-random-proportional rule and a pheromone adjustment mechinism are constructed to balance conflicts between the optimization objectives. At last, a Pareto optimal set is acquired. Evaluation functions based on validity and tendency of reasoning paths are defined to optimize noninferior set, through which the final fault causes can be identified according to decision-making demands, thus realize fault reasoning of the multi-constraint and multi-objective complex system. Reasoning results demonstrate that the improved multi-objective ant colony optimization(IMACO) can realize reasoning and locating fault positions precisely by solving the multi-objective fault diagnosis model, which provides a new method to solve the problem of multi-constraint and multi-objective fault diagnosis and reasoning of complex system.

High Spectral Resolution Infrared and Raman Lidar Observations for the ARM Program: Clear and Cloudy Sky Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Revercomb, Henry; Tobin, David; Knuteson, Robert

2009-06-17

This grant began with the development of the Atmospheric Emitted Radiance Interferometer (AERI) for ARM. The AERI has provided highly accurate and reliable observations of downwelling spectral radiance (Knuteson et al. 2004a, 2004b) for application to radiative transfer, remote sensing of boundary layer temperature and water vapor, and cloud characterization. One of the major contributions of the ARM program has been its success in improving radiation calculation capabilities for models and remote sensing that evolved from the multi-year, clear-sky spectral radiance comparisons between AERI radiances and line-by-line calculations (Turner et al. 2004). This effort also spurred us to play amore » central role in improving the accuracy of water vapor measurements, again helping ARM lead the way in the community (Turner et al. 2003a, Revercomb et al. 2003). In order to add high-altitude downlooking AERI-like observations over the ARM sites, we began the development of an airborne AERI instrument that has become known as the Scanning High-resolution Interferometer Sounder (Scanning-HIS). This instrument has become an integral part of the ARM Unmanned Aerospace Vehicle (ARM-UAV) program. It provides both a cross-track mapping view of the earth and an uplooking view from the 12-15 km altitude of the Scaled Composites Proteus aircraft when flown over the ARM sites for IOPs. It has successfully participated in the first two legs of the “grand tour” of the ARM sites (SGP and NSA), resulting in a very good comparison with AIRS observations in 2002 and in an especially interesting data set from the arctic during the Mixed-Phase Cloud Experiment (M-PACE) in 2004.« less

Improving multi-objective reservoir operation optimization with sensitivity-informed problem decomposition

NASA Astrophysics Data System (ADS)

Chu, J. G.; Zhang, C.; Fu, G. T.; Li, Y.; Zhou, H. C.

2015-04-01

This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce the computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed problem decomposition dramatically reduces the computational demands required for attaining high quality approximations of optimal tradeoff relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed problem decomposition and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform problem decomposition when solving the complex multi-objective reservoir operation problems.

The Impact of Providing Vision Screening and Free Eyeglasses on Academic Outcomes: Evidence from a Randomized Trial in Title I Elementary Schools in Florida

PubMed Central

West, Kristine L.; Lee, Jongwook

2018-01-01

More than 20 percent of all school-aged children in the United States have vision problems, and low-income and minority children are disproportionately likely to have unmet vision care needs. Vision screening is common in U.S. schools, but it remains an open question whether screening alone is sufficient to improve student outcomes. We implemented a multi-armed randomized controlled trial to evaluate the impact of vision screening, and of vision screening accompanied by eye exams and eyeglasses, provided by a non-profit organization to Title I elementary schools in three large central Florida school districts. We find that providing additional/enhanced screening alone is generally insufficient to improve student achievement in math and reading. In contrast, providing screening along with free eye exams and free eyeglasses to students with vision problems improved student achievement as measured by standardized test scores. We find, averaging over all students (including those without vision problems), that this more comprehensive intervention increased the probability of passing the Florida Comprehensive Achievement Tests (FCAT) in reading and math by approximately 2.0 percentage points. We also present evidence that indicates that this impact fades out over time, indicating that follow-up actions after the intervention may be necessary to sustain these estimated achievement gains. PMID:29693366

Does "hidden undercuffing" occur among obese patients? Effect of arm sizes and other predictors of the difference between wrist and upper arm blood pressures.

PubMed

Doshi, Hardik; Weder, Alan B; Bard, Robert L; Brook, Robert D

2010-02-01

Arm size can affect the accuracy of blood pressure (BP) measurement, and "undercuffing" of large upper arms is likely to be a growing problem. Therefore, the authors investigated the relationship between upper arm and wrist readings. Upper arm and wrist circumferences and BP were measured in 261 consecutive patients. Upper arm auscultation and wrist BP was measured in triplicate, rotating measurements every 30 seconds between sites. Upper arm BP was 131.9+/-20.6/71.6+/-12.6 mm Hg in an obese population (body mass index, 30.6+/-6.6 kg/m(2)) with mean upper arm size of 30.7+/-5.1 cm. Wrist BP was higher (2.6+/-9.2 mm Hg and 4.9+/-6.6 mm Hg, respectively, P<.001); however, there was moderate concordance for the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) strata (kappa value=0.27-0.71), and the difference was >or=5 mm Hg in 72% of the patients. The authors conclude that there was poor concordance between arm and wrist BP measurement and found no evidence that "hidden undercuffing" was associated with obesity; therefore, they do not support routine use of wrist BP measurements.

Integrated multi-choice goal programming and multi-segment goal programming for supplier selection considering imperfect-quality and price-quantity discounts in a multiple sourcing environment

NASA Astrophysics Data System (ADS)

Chang, Ching-Ter; Chen, Huang-Mu; Zhuang, Zheng-Yun

2014-05-01

Supplier selection (SS) is a multi-criteria and multi-objective problem, in which multi-segment (e.g. imperfect-quality discount (IQD) and price-quantity discount (PQD)) and multi-aspiration level problems may be significantly important; however, little attention had been given to dealing with both of them simultaneously in the past. This study proposes a model for integrating multi-choice goal programming and multi-segment goal programming to solve the above-mentioned problems by providing the following main contributions: (1) it allows decision-makers to set multiple aspiration levels on the right-hand side of each goal to suit real-world situations, (2) the PQD and IQD conditions are considered in the proposed model simultaneously and (3) the proposed model can solve a SS problem with n suppliers where each supplier offers m IQD with r PQD intervals, where only ? extra binary variables are required. The usefulness of the proposed model is explained using a real case. The results indicate that the proposed model not only can deal with a SS problem with multi-segment and multi-aspiration levels, but also can help the decision-maker to find the appropriate order quantities for each supplier by considering cost, quality and delivery.

Dust-trapping Vortices and a Potentially Planet-triggered Spiral Wake in the Pre-transitional Disk of V1247 Orionis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kraus, Stefan; Kreplin, Alexander; Young, Alison K.

The radial drift problem constitutes one of the most fundamental problems in planet formation theory, as it predicts particles to drift into the star before they are able to grow to planetesimal size. Dust-trapping vortices have been proposed as a possible solution to this problem, as they might be able to trap particles over millions of years, allowing them to grow beyond the radial drift barrier. Here, we present ALMA 0.″04 resolution imaging of the pre-transitional disk of V1247 Orionis that reveals an asymmetric ring as well as a sharply confined crescent structure, resembling morphologies seen in theoretical models ofmore » vortex formation. The asymmetric ring (at 0.″17 = 54 au separation from the star) and the crescent (at 0.″38 = 120 au) seem smoothly connected through a one-armed spiral-arm structure that has been found previously in scattered light. We propose a physical scenario with a planet orbiting at ∼0.″3 ≈ 100 au, where the one-armed spiral arm detected in polarized light traces the accretion stream feeding the protoplanet. The dynamical influence of the planet clears the gap between the ring and the crescent and triggers two vortices that trap millimeter-sized particles, namely, the crescent and the bright asymmetry seen in the ring. We conducted dedicated hydrodynamics simulations of a disk with an embedded planet, which results in similar spiral-arm morphologies as seen in our scattered-light images. At the position of the spiral wake and the crescent we also observe {sup 12}CO(3-2) and H{sup 12}CO{sup +} (4-3) excess line emission, likely tracing the increased scale-height in these disk regions.« less

Dust-trapping Vortices and a Potentially Planet-triggered Spiral Wake in the Pre-transitional Disk of V1247 Orionis

NASA Astrophysics Data System (ADS)

Kraus, Stefan; Kreplin, Alexander; Fukugawa, Misato; Muto, Takayuki; Sitko, Michael L.; Young, Alison K.; Bate, Matthew R.; Grady, Carol; Harries, Tim T.; Monnier, John D.; Willson, Matthew; Wisniewski, John

2017-10-01

The radial drift problem constitutes one of the most fundamental problems in planet formation theory, as it predicts particles to drift into the star before they are able to grow to planetesimal size. Dust-trapping vortices have been proposed as a possible solution to this problem, as they might be able to trap particles over millions of years, allowing them to grow beyond the radial drift barrier. Here, we present ALMA 0.″04 resolution imaging of the pre-transitional disk of V1247 Orionis that reveals an asymmetric ring as well as a sharply confined crescent structure, resembling morphologies seen in theoretical models of vortex formation. The asymmetric ring (at 0.″17 = 54 au separation from the star) and the crescent (at 0.″38 = 120 au) seem smoothly connected through a one-armed spiral-arm structure that has been found previously in scattered light. We propose a physical scenario with a planet orbiting at ˜0.″3 ≈ 100 au, where the one-armed spiral arm detected in polarized light traces the accretion stream feeding the protoplanet. The dynamical influence of the planet clears the gap between the ring and the crescent and triggers two vortices that trap millimeter-sized particles, namely, the crescent and the bright asymmetry seen in the ring. We conducted dedicated hydrodynamics simulations of a disk with an embedded planet, which results in similar spiral-arm morphologies as seen in our scattered-light images. At the position of the spiral wake and the crescent we also observe 12CO(3-2) and H12CO+ (4-3) excess line emission, likely tracing the increased scale-height in these disk regions.

Spectral Invariance Principles Observed in Spectral Radiation Measurements of the Transition Zone

NASA Technical Reports Server (NTRS)

Marshak, Alexander

2011-01-01

The main theme for our research is the understanding and closure of the surface spectral shortwave radiation problem in fully 3D cloud situations by combining the new ARM scanning radars, shortwave spectrometers, and microwave radiometers with the arsenal of radiative transfer tools developed by our group. In particular, we define first a large number of cloudy test cases spanning all 3D possibilities not just the customary uniform-overcast ones. Second, for each case, we define a "Best Estimate of Clouds That Affect Shortwave Radiation" using all relevant ARM instruments, notably the new scanning radars, and contribute this to the ARM Archive. Third, we test the ASR-signature radiative transfer model RRTMG_SW for those cases, focusing on the near-IR because of long-standing problems in this spectral region, and work with the developers to improve RRTMG_SW in order to increase its penetration into the modeling community.

Motion and force control for multiple cooperative manipulators

NASA Technical Reports Server (NTRS)

Wen, John T.; Kreutz, Kenneth

1989-01-01

The motion and force control of multiple robot arms manipulating a commonly held object is addressed. A general control paradigm that decouples the motion and force control problems is introduced. For motion control, there are three natural choices: (1) joint torques, (2) arm-tip force vectors, and (3) the acceleration of a generalized coordinate. Choice (1) allows a class of relatively model-independent control laws by exploiting the Hamiltonian structure of the open-loop system; (2) and (3) require the full model information but produce simpler problems. To resolve the nonuniqueness of the joint torques, two methods are introduced. If the arm and object models are available, the allocation of the desired end-effector control force to the joint actuators can be optimized; otherwise the internal force can be controlled about some set point. It is shown that effective force regulation can be achieved even if little model information is available.

Small-angle X-ray solution scattering study of the multi-aminoacyl-tRNA synthetase complex reveals an elongated and multi-armed particle.

PubMed

Dias, José; Renault, Louis; Pérez, Javier; Mirande, Marc

2013-08-16

In animal cells, nine aminoacyl-tRNA synthetases are associated with the three auxiliary proteins p18, p38, and p43 to form a stable and conserved large multi-aminoacyl-tRNA synthetase complex (MARS), whose molecular mass has been proposed to be between 1.0 and 1.5 MDa. The complex acts as a molecular hub for coordinating protein synthesis and diverse regulatory signal pathways. Electron microscopy studies defined its low resolution molecular envelope as an overall rather compact, asymmetric triangular shape. Here, we have analyzed the composition and homogeneity of the native mammalian MARS isolated from rabbit liver and characterized its overall internal structure, size, and shape at low resolution by hydrodynamic methods and small-angle x-ray scattering in solution. Our data reveal that the MARS exhibits a much more elongated and multi-armed shape than expected from previous reports. The hydrodynamic and structural features of the MARS are large compared with other supramolecular assemblies involved in translation, including ribosome. The large dimensions and non-compact structural organization of MARS favor a large protein surface accessibility for all its components. This may be essential to allow structural rearrangements between the catalytic and cis-acting tRNA binding domains of the synthetases required for binding the bulky tRNA substrates. This non-compact architecture may also contribute to the spatiotemporal controlled release of some of its components, which participate in non-canonical functions after dissociation from the complex.

Laparoscopic Surgical Treatment of Severe Obesity Combined with Gastroesophageal Reflux Disease: A Pilot Randomized Two-Arm Controlled Clinical Study

ERIC Educational Resources Information Center

Ospanov, Oral B.; Orekeshova, Akzhunis M.; Fursov, Roman A.; Yelemesov, Aset A.

2016-01-01

Obesity and gastroesophageal reflux disease (GERD) are serious medical, social, and economic problems of modern society. A pilot randomized two-arm controlled clinical study was conducted to compare laparoscopic plication of the greater gastric curvature combined with Nissen fundoplication (LFN+LGP) versus only Nissen fundoplication (LFN). The…

The opto-mechanical design for GMOX: a next-generation instrument concept for Gemini

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Barkhouser, Robert; Robberto, Massimo; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy M.

2016-08-01

We present the opto-mechanical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph, a potential next-generation (Gen-4 #3) facility-class instrument for Gemini. GMOX is a wide-band, multi-object, spectrograph with spectral coverage spanning 350 nm to 2.4 um with a nominal resolving power of R 5000. Through the use of Digital Micromirror Device (DMD) technology, GMOX will be able to acquire spectra from hundreds of sources simultaneously, offering unparalleled flexibility in target selection. Utilizing this technology, GMOX can rapidly adapt individual slits to either seeing-limited or diffraction-limited conditions. The optical design splits the bandpass into three arms, blue, red, and near infrared, with the near-infrared arm being split into three channels covering the Y+J band, H band, and K band. A slit viewing camera in each arm provides imaging capability for target acquisition and fast-feedback for adaptive optics control with either ALTAIR (Gemini North) or GeMS (Gemini South). Mounted at the Cassegrain focus, GMOX is a large (1.3 m x 2.8 m x 2.0 m) complex instrument, with six dichroics, three DMDs (one per arm), five science cameras, and three acquisition cameras. Roughly half of these optics, including one DMD, operate at cryogenic temperature. To maximize stiffness and simplify assembly and alignment, the opto-mechanics are divided into three main sub-assemblies, including a near-infrared cryostat, each having sub-benches to facilitate ease of alignment and testing of the optics. In this paper we present the conceptual opto-mechanical design of GMOX, with an emphasis on the mounting strategy for the optics and the thermal design details related to the near-infrared cryostat.

OxMaR: open source free software for online minimization and randomization for clinical trials.

PubMed

O'Callaghan, Christopher A

2014-01-01

Minimization is a valuable method for allocating participants between the control and experimental arms of clinical studies. The use of minimization reduces differences that might arise by chance between the study arms in the distribution of patient characteristics such as gender, ethnicity and age. However, unlike randomization, minimization requires real time assessment of each new participant with respect to the preceding distribution of relevant participant characteristics within the different arms of the study. For multi-site studies, this necessitates centralized computational analysis that is shared between all study locations. Unfortunately, there is no suitable freely available open source or free software that can be used for this purpose. OxMaR was developed to enable researchers in any location to use minimization for patient allocation and to access the minimization algorithm using any device that can connect to the internet such as a desktop computer, tablet or mobile phone. The software is complete in itself and requires no special packages or libraries to be installed. It is simple to set up and run over the internet using online facilities which are very low cost or even free to the user. Importantly, it provides real time information on allocation to the study lead or administrator and generates real time distributed backups with each allocation. OxMaR can readily be modified and customised and can also be used for standard randomization. It has been extensively tested and has been used successfully in a low budget multi-centre study. Hitherto, the logistical difficulties involved in minimization have precluded its use in many small studies and this software should allow more widespread use of minimization which should lead to studies with better matched control and experimental arms. OxMaR should be particularly valuable in low resource settings.

Tissue dielectric constant (TDC) as an index of localized arm skin water: differences between measuring probes and genders.

PubMed

Mayrovitz, H N; Weingrad, D N; Brlit, F; Lopez, L B; Desfor, R

2015-03-01

An easily measured, non-invasive, quantitative estimate of local skin tissue water is useful to assess local lymphedema and its change. One method uses skin tissue dielectric constant (TDC) values that at 300 MHz TDC depend on free and bound water within the measurement volume. In practice such measurements have been done with a research-type multi-probe, but recently a hand-held compact-probe has become available that may be more clinically convenient. Because most available published data is based on multiprobe measurements it is important to characterize possible differences between devices that unless known might lead to ambiguous quantitative comparisons between TDC values. Thus, our purpose was to evaluate potential differences in measured TDC values between multi-probe and compact-probe devices with respect to probe effective sampling depth, anatomical site, and gender and also to compare compact-probe TDC values measured on women with and without breast cancer (BC). TDC was measured bilaterally on forearms and biceps of 32 male and 32 female volunteers and on 12 female patients awaiting surgery for breast cancer. Results show that 1) TDC values at 2.5 mm depth were significantly less than at 1.5 mm; 2) Female TDC values were significantly less than male values; 3) TDC values were not different between females with and without BC; and 4) dominant/non-dominant arm TDC ratios were not significantly different for any probe among genders or arm anatomical site. These findings indicate that probe type differences in absolute TDC values are present and should be taken into account when TDC values are compared. However, comparisons based on inter-arm TDC ratios are not statistically different among probes with respect to gender or anatomical location.

Volumetric flow imaging reveals the importance of vortex ring formation in squid swimming tail-first and arms-first.

PubMed

Bartol, Ian K; Krueger, Paul S; Jastrebsky, Rachel A; Williams, Sheila; Thompson, Joseph T

2016-02-01

Squids use a pulsed jet and fin movements to swim both arms-first (forward) and tail-first (backward). Given the complexity of the squid multi-propulsor system, 3D velocimetry techniques are required for the comprehensive study of wake dynamics. Defocusing digital particle tracking velocimetry, a volumetric velocimetry technique, and high-speed videography were used to study arms-first and tail-first swimming of brief squid Lolliguncula brevis over a broad range of speeds [0-10 dorsal mantle lengths (DML) s(-1)] in a swim tunnel. Although there was considerable complexity in the wakes of these multi-propulsor swimmers, 3D vortex rings and their derivatives were prominent reoccurring features during both tail-first and arms-first swimming, with the greatest jet and fin flow complexity occurring at intermediate speeds (1.5-3.0 DML s(-1)). The jet generally produced the majority of thrust during rectilinear swimming, increasing in relative importance with speed, and the fins provided no thrust at speeds >4.5 DML s(-1). For both swimming orientations, the fins sometimes acted as stabilizers, producing negative thrust (drag), and consistently provided lift at low/intermediate speeds (<2.0 DML s(-1)) to counteract negative buoyancy. Propulsive efficiency (η) increased with speed irrespective of swimming orientation, and η for swimming sequences with clear isolated jet vortex rings was significantly greater (η=78.6±7.6%, mean±s.d.) than that for swimming sequences with clear elongated regions of concentrated jet vorticity (η=67.9±19.2%). This study reveals the complexity of 3D vortex wake flows produced by nekton with hydrodynamically distinct propulsors. © 2016. Published by The Company of Biologists Ltd.

Learning to Select Actions with Spiking Neurons in the Basal Ganglia

PubMed Central

Stewart, Terrence C.; Bekolay, Trevor; Eliasmith, Chris

2012-01-01

We expand our existing spiking neuron model of decision making in the cortex and basal ganglia to include local learning on the synaptic connections between the cortex and striatum, modulated by a dopaminergic reward signal. We then compare this model to animal data in the bandit task, which is used to test rodent learning in conditions involving forced choice under rewards. Our results indicate a good match in terms of both behavioral learning results and spike patterns in the ventral striatum. The model successfully generalizes to learning the utilities of multiple actions, and can learn to choose different actions in different states. The purpose of our model is to provide both high-level behavioral predictions and low-level spike timing predictions while respecting known neurophysiology and neuroanatomy. PMID:22319465

NASA's Asteroid Redirect Mission (ARM)

NASA Astrophysics Data System (ADS)

Abell, Paul; Mazanek, Dan; Reeves, David; Naasz, Bo; Cichy, Benjamin

2015-11-01

The National Aeronautics and Space Administration (NASA) is developing a robotic mission to visit a large near-Earth asteroid (NEA), collect a multi-ton boulder from its surface, and redirect it into a stable orbit around the Moon. Once returned to cislunar space in the mid-2020s, astronauts will explore the boulder and return to Earth with samples. This Asteroid Redirect Mission (ARM) is part of NASA’s plan to advance the technologies, capabilities, and spaceflight experience needed for a human mission to the Martian system in the 2030s. Subsequent human and robotic missions to the asteroidal material would also be facilitated by its return to cislunar space. Although ARM is primarily a capability demonstration mission (i.e., technologies and associated operations), there exist significant opportunities to advance our knowledge of small bodies in the synergistic areas of science, planetary defense, asteroidal resources and in-situ resource utilization (ISRU), and capability and technology demonstrations. In order to maximize the knowledge return from the mission, NASA is organizing an ARM Investigation Team, which is being preceded by the Formulation Assessment and Support Team. These teams will be comprised of scientists, technologists, and other qualified and interested individuals to help plan the implementation and execution of ARM. An overview of robotic and crewed segments of ARM, including the mission requirements, NEA targets, and mission operations, will be provided along with a discussion of the potential opportunities associated with the mission.

The Asteroid Redirect Mission (ARM)

NASA Technical Reports Server (NTRS)

Abell, Paul

2015-01-01

The National Aeronautics and Space Administration (NASA) is developing a robotic mission to visit a large near-Earth asteroid (NEA), collect a multi-ton boulder from its surface, and redirect it into a stable orbit around the Moon. Once returned to cislunar space in the mid-2020s, astronauts will explore the boulder and return to Earth with samples. This Asteroid Redirect Mission (ARM) is part of NASA's plan to advance the technologies, capabilities, and spaceflight experience needed for a human mission to the Martian system in the 2030s. Subsequent human and robotic missions to the asteroidal material would also be facilitated by its return to cislunar space. Although ARM is primarily a capability demonstration mission (i.e., technologies and associated operations), there exist significant opportunities to advance our knowledge of small bodies in the synergistic areas of science, planetary defense, asteroidal resources and in-situ resource utilization (ISRU), and capability and technology demonstrations. In order to maximize the knowledge return from the mission, NASA is organizing an ARM Investigation Team, which is being preceded by the Formulation Assessment and Support Team. These teams will be comprised of scientists, technologists, and other qualified and interested individuals to help plan the implementation and execution of ARM. An overview of robotic and crewed segments of ARM, including the mission requirements, NEA targets, and mission operations, will be provided along with a discussion of the potential opportunities associated with the mission.

Blue Collar Science

ERIC Educational Resources Information Center

Vineyard, Jerry D.

1970-01-01

Discusses environmental problems that prevent quality living. To overcome these problems we must arm ourselves with the facts relating to environmental crisis and bring them to the attention of people with power; and press for increased environmental awareness among students. (BR)

An MR-compatible gyroscope-based arm movement tracking system.

PubMed

Shirinbayan, S Iman; Rieger, Jochem W

2017-03-15

Functional magnetic resonance imaging is well suited to link neural population activation with movement parameters of complex natural arm movements. However, currently existing MR-compatible arm tracking devices are not constructed to measure arm joint movement parameters of unrestricted movements. Therefore, to date most research focuses on simple arm movements or includes very little knowledge about the actual movement kinematics. We developed a low cost gyroscope-based arm movement tracking system (GAMTS) that features MR-compatibility. The system consists of dual-axis analogue gyroscopes that measure rotations of upper and lower arm joints. After MR artifact reduction, the rotation angles of the individual arm joints are calculated and used to animate a realistic arm model that is implemented in the OpenSim platform. The OpenSim platform can then provide the kinematics of any point on the arm model. In order to demonstrate the capabilities of the system, we first assessed the quality of reconstructed wrist movements in a low-noise environment where typical MR-related problems are absent and finally, we validated the reconstruction in the MR environment. The system provides the kinematics of the whole arm when natural unrestricted arm movements are performed inside the MR-scanner. The GAMTS is reliably capable of reconstructing the kinematics of trajectories and the reconstruction error is small in comparison with the movement induced variation of speed, displacement, and rotation. Moreover, the system can be used to probe brain areas for their correlation with movement kinematics. Copyright © 2017 Elsevier B.V. All rights reserved.

Design of a modular digital computer system

NASA Technical Reports Server (NTRS)

1980-01-01

A Central Control Element (CCE) module which controls the Automatically Reconfigurable Modular System (ARMS) and allows both redundant processing and multi-computing in the same computer with real time mode switching, is discussed. The same hardware is used for either reliability enhancement, speed enhancement, or for a combination of both.

76 FR 66048 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-25

.... (iii) Description and Quantity or Quantities of Articles or Services under Consideration for Purchase... High Mobility Multi-Purpose Wheeled Vehicles (HMMWVs), 1 lot AN/MPQ- 64F1 SENTINEL Radar software, 290...-Launched Advanced Medium Range Air-to-Air Missile (SL-AMRAAM) software to support Oman's Ground Based Air...

77 FR 53184 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

..., multi-field of view EO/IR system. The system provides color daylight TV and night time IR video with a... along with ground moving target indicator (GMTI) modes. It will also have two onboard workstations that...-locate, collect, and display the relevant information to two operators for analysis and recording...

VizieR Online Data Catalog: SAMI Galaxy Survey: rotators classification (van de Sande+, 2017)

NASA Astrophysics Data System (ADS)

van de Sande, J.; Bland-Hawthorn, J.; Fogarty, L. M. R.; Cortese, L.; D'Eugenio, F.; Croom, S. M.; Scott, N.; Allen, J. T.; Brough, S.; Bryant, J. J.; Cecil, G.; Colless, M.; Couch, W. J.; Davies, R.; Elahi, P. J.; Foster, C.; Goldstein, G.; Goodwin, M.; Groves, B.; Ho, I.-T.; Jeong, H.; Jones, D. H.; Konstantopoulos, I. S.; Lawrence, J. S.; Leslie, S. K.; Lopez-Sanchez, A. R.; McDermid, R. M.; McElroy, R.; Medling, A. M.; Oh, S.; Owers, M. S.; Richards, S. N.; Schaefer, A. L.; Sharp, R.; Sweet, S. M.; Taranu, D.; Tonini, C.; Walcher, C. J.; Yi, S. K.

2017-08-01

The SAMI instrument and Galaxy Survey is described in detail in Croom+ (2012MNRAS.421..872C) and Bryant+ (2015MNRAS.447.2857B). SAMI is a multi-object integral field spectrograph on the 3.9m Anglo Australian Telescope (AAT). For the SAMI Galaxy Survey, the 580V grating is used in the blue arm of the spectrograph, which results in a resolution of R~1700 with wavelength coverage of 3700-5700Å. In the red arm, the higher resolution grating 1000R is used, which gives an R~4500 over the range 6300-7400Å. We use 24 unsaturated, unblended CuAr arc lines in the blue arm, and 12 lines in the red arm, from 16 frames between 2013 March 05 and 2015 August 17, for all 819 fibers. The survey has four volume-limited galaxy samples derived from cuts in stellar mass in the Galaxy and Mass Assembly (GAMA) G09, G12, and G15 regions (Driver+ 2011, J/MNRAS/413/971). (2 data files).

Distributed coupling and multi-frequency microwave accelerators

DOEpatents

Tantawi, Sami G.; Li, Zenghai; Borchard, Philipp

2016-07-05

A microwave circuit for a linear accelerator has multiple metallic cell sections, a pair of distribution waveguide manifolds, and a sequence of feed arms connecting the manifolds to the cell sections. The distribution waveguide manifolds are connected to the cell sections so that alternating pairs of cell sections are connected to opposite distribution waveguide manifolds. The distribution waveguide manifolds have concave modifications of their walls opposite the feed arms, and the feed arms have portions of two distinct widths. In some embodiments, the distribution waveguide manifolds are connected to the cell sections by two different types of junctions adapted to allow two frequency operation. The microwave circuit may be manufactured by making two quasi-identical parts, and joining the two parts to form the microwave circuit, thereby allowing for many manufacturing techniques including electron beam welding, and thereby allowing the use of un-annealled copper alloys, and hence greater tolerance to high gradient operation.

Evolution in Cloud Population Statistics of the MJO: From AMIE Field Observations to Global-Cloud Permitting Models Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kollias, Pavlos

This is a multi-institutional, collaborative project using a three-tier modeling approach to bridge field observations and global cloud-permitting models, with emphases on cloud population structural evolution through various large-scale environments. Our contribution was in data analysis for the generation of high value cloud and precipitation products and derive cloud statistics for model validation. There are two areas in data analysis that we contributed: the development of a synergistic cloud and precipitation cloud classification that identify different cloud (e.g. shallow cumulus, cirrus) and precipitation types (shallow, deep, convective, stratiform) using profiling ARM observations and the development of a quantitative precipitation ratemore » retrieval algorithm using profiling ARM observations. Similar efforts have been developed in the past for precipitation (weather radars), but not for the millimeter-wavelength (cloud) radar deployed at the ARM sites.« less

International Space Station (ISS)

NASA Image and Video Library

2002-06-01

Pictured here is the Space Shuttle Orbiter Endeavour, STS-111 mission insignia. The International Space Station (ISS) recieved a new crew, Expedition Five, replacing Expedition Four after a record-setting 196 days in space, when STS-111 visited in June 2002. Three spacewalks enabled the STS-111 crew to accomplish additional mission objectives: the delivery and installation of a new platform for the ISS robotic arm, the Mobile Base System (MBS) which is an important part of the Station's Mobile Servicing System allowing the robotic arm to travel the length of the Station; the replacement of a wrist roll joint on the Station's robotic arm; and unloading supplies and science experiments from the Leonardo Multi-Purpose Logistics Module, which made its third trip to the orbital outpost. The STS-111 mission, the 14th Shuttle mission to visit the ISS, was launched on June 5, 2002 and landed June 19, 2002.

A Low Power, Parallel Wearable Multi-Sensor System for Human Activity Evaluation.

PubMed

Li, Yuecheng; Jia, Wenyan; Yu, Tianjian; Luan, Bo; Mao, Zhi-Hong; Zhang, Hong; Sun, Mingui

2015-04-01

In this paper, the design of a low power heterogeneous wearable multi-sensor system, built with Zynq System-on-Chip (SoC), for human activity evaluation is presented. The powerful data processing capability and flexibility of this SoC represent significant improvements over our previous ARM based system designs. The new system captures and compresses multiple color images and sensor data simultaneously. Several strategies are adopted to minimize power consumption. Our wearable system provides a new tool for the evaluation of human activity, including diet, physical activity and lifestyle.

Well Casing Baseline Analysis for the Big Hill Strategic Petroleum Reserve Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moriarty, Dylan Michael; Roberts, Barry L.

This report analyzes data from multi-arm caliper (MAC) surveys taken at the Big Hill SPR site to determine the most likely casing weights within each well. Radial arm data from MAC surveys were used to calculate the approximate wall thickness of each well. Results from this study indicate that (1) most wells at the site have thinner wall thicknesses than expected, (2) most wells experienced an acute increase in diameter near the salt/caprock interface, and (3) there were isolated instances of well sections being the wrong casing weight. All three findings could have a negative impact on well integrity.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51263 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51264 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51265 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm (out of frame) grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

Hand-arm vibration exposure monitoring with wearable sensor module.

PubMed

Austad, Hanne O; Røed, Morten H; Liverud, Anders E; Dalgard, Steffen; Seeberg, Trine M

2013-01-01

Vibration exposure is a serious risk within work physiology for several work groups. Combined with cold artic climate, the risk for permanent harm is even higher. Equipment that can monitor the vibration exposure and warn the user when at risk will provide a safer work environment for these work groups. This study evaluates whether data from a wearable wireless multi-parameter sensor module can be used to estimate vibration exposure and exposure time. This work has been focused on the characterization of the response from the accelerometer in the sensor module and the optimal location of the module in the hand-arm configuration.

Exploiting the Dynamics of Soft Materials for Machine Learning

PubMed Central

Hauser, Helmut; Li, Tao; Pfeifer, Rolf

2018-01-01

Abstract Soft materials are increasingly utilized for various purposes in many engineering applications. These materials have been shown to perform a number of functions that were previously difficult to implement using rigid materials. Here, we argue that the diverse dynamics generated by actuating soft materials can be effectively used for machine learning purposes. This is demonstrated using a soft silicone arm through a technique of multiplexing, which enables the rich transient dynamics of the soft materials to be fully exploited as a computational resource. The computational performance of the soft silicone arm is examined through two standard benchmark tasks. Results show that the soft arm compares well to or even outperforms conventional machine learning techniques under multiple conditions. We then demonstrate that this system can be used for the sensory time series prediction problem for the soft arm itself, which suggests its immediate applicability to a real-world machine learning problem. Our approach, on the one hand, represents a radical departure from traditional computational methods, whereas on the other hand, it fits nicely into a more general perspective of computation by way of exploiting the properties of physical materials in the real world. PMID:29708857

Exploiting the Dynamics of Soft Materials for Machine Learning.

PubMed

Nakajima, Kohei; Hauser, Helmut; Li, Tao; Pfeifer, Rolf

2018-06-01

Soft materials are increasingly utilized for various purposes in many engineering applications. These materials have been shown to perform a number of functions that were previously difficult to implement using rigid materials. Here, we argue that the diverse dynamics generated by actuating soft materials can be effectively used for machine learning purposes. This is demonstrated using a soft silicone arm through a technique of multiplexing, which enables the rich transient dynamics of the soft materials to be fully exploited as a computational resource. The computational performance of the soft silicone arm is examined through two standard benchmark tasks. Results show that the soft arm compares well to or even outperforms conventional machine learning techniques under multiple conditions. We then demonstrate that this system can be used for the sensory time series prediction problem for the soft arm itself, which suggests its immediate applicability to a real-world machine learning problem. Our approach, on the one hand, represents a radical departure from traditional computational methods, whereas on the other hand, it fits nicely into a more general perspective of computation by way of exploiting the properties of physical materials in the real world.

Data management and scientific integration within the Atmospheric Radiation Measurement Program

NASA Technical Reports Server (NTRS)

Gracio, Deborah K.; Hatfield, Larry D.; Yates, Kenneth R.; Voyles, Jimmy W.; Tichler, Joyce L.; Cederwall, Richard T.; Laufersweiler, Mark J.; Leach, Martin J.; Singley, Paul

1995-01-01

The Atmospheric Radiation Measurement (ARM) Program has been developed by the U.S. Department of Energy with the goal to improve the predictive capabilities of General Circulation Models (GCM's) in their treatment of clouds and radiative transfer effects. To achieve this goal, three experimental testbeds were designed for the deployment of instruments that will collect atmospheric data used to drive the GCM's. Each site, known as a Cloud and Radiation Testbed (CART), consists of a highly available, redundant data system for the collection of data from a variety of instrumentation. The first CART site was deployed in April 1992 in the Southern Great Plains (SGP), Lamont, Oklahoma, with the other two sites to follow in September 1995 in the Tropical Western Pacific and in 1997 on the North Slope of Alaska. Approximately 400 MB of data are transferred per day via the Internet from the SGP site to the ARM Experiment Center at Pacific Northwest Laboratory in Richland, Washington. The Experiment Center is central to the ARM data path and provides for the collection, processing, analysis, and delivery of ARM data. Data are received from the CART sites from a variety of instrumentation, observational systems, amd external data sources. The Experiment Center processes these data streams on a continuous basis to provide derived data products to the ARM Science Team in near real-time while providing a three-month running archive of data. A primary requirement of the ARM Program is to preserve and protect all data produced or acquired. This function is performed at Oak Ridge National Laboratory where leading edge technology is employed for the long-term storage of ARM data. The ARM Archive provides access to data for participation outside of the ARM Program. The ARM Program involves a collaborative effort by teams from various DOE National Laboratories, providing multi-disciplinary areas of expertise. This paper will discuss the collaborative methods in which the ARM teams translate the scientific goals of the Program into data products. By combining atmospheric scientists, systems engineers, and software engineers, the ARM Program has successfully designed and developed an environment where advances in understanding the parameterizations of GCM's can be made.

Study of Behaviour Problems in a Paediatric Outpatient Department.

PubMed

Prakash, J; Sudarsanan, S; Pardal, P K; Chaudhury, S

2006-10-01

Behaviour problems in children still needs precise definition, explicit criterion and assessment on multiple paradigms. Fifty children of the age group 6-14 years, from paediatric outpatient department, selected after randomisation were assessed for behaviour problems with the child behaviour checklist. The data collected was analysed using appropriate statistical tests. 40% children were above cutoff score. Mean child behaviour check list (CBCL) score was 40.6. Total of 72% children were from armed forces background of whom 9% were siblings of officers. 30.6% children from the armed forces background were above the cutoff score. There was no significant difference in the behaviour problems between different age groups and sex. There was no significant difference in behaviour problems between children of officers, other ranks or various income groups. Female children had behaviour problems like "too concerned with neatness or cleanliness", "feels has to be perfect" and "argues a lot" where as male children had behaviour problems like "Does not feel guilty after misbehaving", "argues a lot" and "restless". Behaviour problems in the subjects were externalizing ones. No specific trend was found in children of defence personnel vis-a-vis children of civilian population.

Whole arm manipulation planning based on feedback velocity fields and sampling-based techniques.

PubMed

Talaei, B; Abdollahi, F; Talebi, H A; Omidi Karkani, E

2013-09-01

Changing the configuration of a cooperative whole arm manipulator is not easy while enclosing an object. This difficulty is mainly because of risk of jamming caused by kinematic constraints. To reduce this risk, this paper proposes a feedback manipulation planning algorithm that takes grasp kinematics into account. The idea is based on a vector field that imposes perturbation in object motion inducing directions when the movement is considerably along manipulator redundant directions. Obstacle avoidance problem is then considered by combining the algorithm with sampling-based techniques. As experimental results confirm, the proposed algorithm is effective in avoiding jamming as well as obstacles for a 6-DOF dual arm whole arm manipulator. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Solving intuitionistic fuzzy multi-objective nonlinear programming problem

NASA Astrophysics Data System (ADS)

Anuradha, D.; Sobana, V. E.

2017-11-01

This paper presents intuitionistic fuzzy multi-objective nonlinear programming problem (IFMONLPP). All the coefficients of the multi-objective nonlinear programming problem (MONLPP) and the constraints are taken to be intuitionistic fuzzy numbers (IFN). The IFMONLPP has been transformed into crisp one and solved by using Kuhn-Tucker condition. Numerical example is provided to illustrate the approach.

An agent-vector-host-environment model for controlling small arms and light weapons.

PubMed

Pinto, Andrew D; Sharma, Malika; Muggah, Robert

2011-05-01

Armed violence is a significant public health problem. It results in fatal and non-fatal injuries and disrupts social and economic processes that are essential to the health of individuals and communities. We argue that an agent-vector-host-environment model can be helpful in understanding and describing the availability and misuse of small arms and light weapons. Moreover, such a model can assist in identifying potential control points and in developing mitigation strategies. These concepts have been developed from analogous vector control programs and are applied to controlling arms to reduce their misuse. So-called 'denormalization' and 'de-legitimization' campaigns that focus on the vector - including the industry producing these commodities - can be based on the experience of public health in controlling tobacco use and exposure. This model can assist health professionals, civil society and governments in developing comprehensive strategies to limit the production, distribution and misuse of small arms and light weapons.

Extended wavelength anisotropy resolved multidimensional emission spectroscopy (ARMES) measurements: better filters, validation standards, and Rayleigh scatter removal methods

NASA Astrophysics Data System (ADS)

Casamayou-Boucau, Yannick; Ryder, Alan G.

2017-09-01

Anisotropy resolved multidimensional emission spectroscopy (ARMES) provides valuable insights into multi-fluorophore proteins (Groza et al 2015 Anal. Chim. Acta 886 133-42). Fluorescence anisotropy adds to the multidimensional fluorescence dataset information about the physical size of the fluorophores and/or the rigidity of the surrounding micro-environment. The first ARMES studies used standard thin film polarizers (TFP) that had negligible transmission between 250 and 290 nm, preventing accurate measurement of intrinsic protein fluorescence from tyrosine and tryptophan. Replacing TFP with pairs of broadband wire grid polarizers enabled standard fluorescence spectrometers to accurately measure anisotropies between 250 and 300 nm, which was validated with solutions of perylene in the UV and Erythrosin B and Phloxine B in the visible. In all cases, anisotropies were accurate to better than ±1% when compared to literature measurements made with Glan Thompson or TFP polarizers. Better dual wire grid polarizer UV transmittance and the use of excitation-emission matrix measurements for ARMES required complete Rayleigh scatter elimination. This was achieved by chemometric modelling rather than classical interpolation, which enabled the acquisition of pure anisotropy patterns over wider spectral ranges. In combination, these three improvements permit the accurate implementation of ARMES for studying intrinsic protein fluorescence.

A real-time robot arm collision detection system

NASA Technical Reports Server (NTRS)

Shaffer, Clifford A.; Herb, Gregory M.

1990-01-01

A data structure and update algorithm are presented for a prototype real time collision detection safety system for a multi-robot environment. The data structure is a variant of the octree, which serves as a spatial index. An octree recursively decomposes 3-D space into eight equal cubic octants until each octant meets some decomposition criteria. The octree stores cylspheres (cylinders with spheres on each end) and rectangular solids as primitives (other primitives can easily be added as required). These primitives make up the two seven degrees-of-freedom robot arms and environment modeled by the system. Octree nodes containing more than a predetermined number N of primitives are decomposed. This rule keeps the octree small, as the entire environment for the application can be modeled using a few dozen primitives. As robot arms move, the octree is updated to reflect their changed positions. During most update cycles, any given primitive does not change which octree nodes it is in. Thus, modification to the octree is rarely required. Incidents in which one robot arm comes too close to another arm or an object are reported. Cycle time for interpreting current joint angles, updating the octree, and detecting/reporting imminent collisions averages 30 milliseconds on an Intel 80386 processor running at 20 MHz.

Prevalence of inter-arm blood pressure difference among clinical out-patients.

PubMed

Sharma, Balkishan; Ramawat, Pramila

2016-04-01

An increased inter-arm blood pressure difference is an easily determined physical finding, may use as an indicator of cardio vascular event and other sever diseases. Authors evaluated 477 patients to determine the prevalence and significance of inter-arm blood pressure difference. 477 routine outdoor patients selected to observe the inter-arm blood pressure difference. Age, height, weight, body mass index, history of disease and blood pressure recorded. The prevalence of ≥10 mmHg systolic inter-arm blood pressure difference was 5.0% was more as compared to 3.8% had diastolic inter-arm blood pressure difference. The prevalence of systolic and diastolic inter-arm difference between 6 to 10 mmHg was 31.4% and 27.9% respectively. Mean systolic inter-arm blood pressure difference was significantly higher among those patients had a multisystem disorder (10.57±0.98 mmHg) and followed by patients with cardiovascular disease (10.22±0.67 mmHg) as compared to healthy patients (2.71±0.96 mmHg). Various diseases highly influenced the increase in blood pressure irrespective of systolic or diastolic was confirmed strongly significant (p<0.001) at different inter arm blood pressure difference levels. This study supports the view of inter-arm blood pressure difference as an alarming stage of increased disease risk that incorporated to investigate potential problems at an early diagnostic stage. A significant mean difference between left and right arm blood pressure recorded for many diseases.

Prevalence of inter-arm blood pressure difference among clinical out-patients

PubMed Central

Sharma, Balkishan; Ramawat, Pramila

2016-01-01

Objectives An increased inter-arm blood pressure difference is an easily determined physical finding, may use as an indicator of cardio vascular event and other sever diseases. Authors evaluated 477 patients to determine the prevalence and significance of inter-arm blood pressure difference. Methodology 477 routine outdoor patients selected to observe the inter-arm blood pressure difference. Age, height, weight, body mass index, history of disease and blood pressure recorded. Results The prevalence of ≥10 mmHg systolic inter-arm blood pressure difference was 5.0% was more as compared to 3.8% had diastolic inter-arm blood pressure difference. The prevalence of systolic and diastolic inter-arm difference between 6 to 10 mmHg was 31.4% and 27.9% respectively. Mean systolic inter-arm blood pressure difference was significantly higher among those patients had a multisystem disorder (10.57±0.98 mmHg) and followed by patients with cardiovascular disease (10.22±0.67 mmHg) as compared to healthy patients (2.71±0.96 mmHg). Various diseases highly influenced the increase in blood pressure irrespective of systolic or diastolic was confirmed strongly significant (p<0.001) at different inter arm blood pressure difference levels. Conclusion This study supports the view of inter-arm blood pressure difference as an alarming stage of increased disease risk that incorporated to investigate potential problems at an early diagnostic stage. A significant mean difference between left and right arm blood pressure recorded for many diseases. PMID:27103905

The PdBI Arcsecond Whirlpool Survey (PAWS): The Role of Spiral Arms in Cloud and Star Formation

NASA Astrophysics Data System (ADS)

Schinnerer, Eva; Meidt, Sharon E.; Colombo, Dario; Chandar, Rupali; Dobbs, Clare L.; García-Burillo, Santiago; Hughes, Annie; Leroy, Adam K.; Pety, Jérôme; Querejeta, Miguel; Kramer, Carsten; Schuster, Karl F.

2017-02-01

The process that leads to the formation of the bright star-forming sites observed along prominent spiral arms remains elusive. We present results of a multi-wavelength study of a spiral arm segment in the nearby grand-design spiral galaxy M51 that belongs to a spiral density wave and exhibits nine gas spurs. The combined observations of the (ionized, atomic, molecular, dusty) interstellar medium with star formation tracers (H II regions, young <10 Myr stellar clusters) suggest (1) no variation in giant molecular cloud (GMC) properties between arm and gas spurs, (2) gas spurs and extinction feathers arising from the same structure with a close spatial relation between gas spurs and ongoing/recent star formation (despite higher gas surface densities in the spiral arm), (3) no trend in star formation age either along the arm or along a spur, (4) evidence for strong star formation feedback in gas spurs, (5) tentative evidence for star formation triggered by stellar feedback for one spur, and (6) GMC associations being not special entities but the result of blending of gas arm/spur cross sections in lower resolution observations. We conclude that there is no evidence for a coherent star formation onset mechanism that can be solely associated with the presence of the spiral density wave. This suggests that other (more localized) mechanisms are important to delay star formation such that it occurs in spurs. The evidence of star formation proceeding over several million years within individual spurs implies that the mechanism that leads to star formation acts or is sustained over a longer timescale.

Arm Locking for the Laser Interferometer Space Antenna

NASA Technical Reports Server (NTRS)

Maghami, P. G.; Thorpe, J. I.; Livas, J.

2009-01-01

The Laser Interferometer Space Antenna (LISA) mission is a planned gravitational wave detector consisting of three spacecraft in heliocentric orbit. Laser interferometry is used to measure distance fluctuations between test masses aboard each spacecraft to the picometer level over a 5 million kilometer separation. Laser frequency fluctuations must be suppressed in order to meet the measurement requirements. Arm-locking, a technique that uses the constellation of spacecraft as a frequency reference, is a proposed method for stabilizing the laser frequency. We consider the problem of arm-locking using classical optimal control theory and find that our designs satisfy the LISA requirements.

Synthesis multi-projector content for multi-projector three dimension display using a layered representation

NASA Astrophysics Data System (ADS)

Qin, Chen; Ren, Bin; Guo, Longfei; Dou, Wenhua

2014-11-01

Multi-projector three dimension display is a promising multi-view glass-free three dimension (3D) display technology, can produce full colour high definition 3D images on its screen. One key problem of multi-projector 3D display is how to acquire the source images of projector array while avoiding pseudoscopic problem. This paper analysis the displaying characteristics of multi-projector 3D display first and then propose a projector content synthetic method using tetrahedral transform. A 3D video format that based on stereo image pair and associated disparity map is presented, it is well suit for any type of multi-projector 3D display and has advantage in saving storage usage. Experiment results show that our method solved the pseudoscopic problem.

Occupational risk factors for ill health in Gulf veterans of the United Kingdom

PubMed Central

Ismail, K.; Blatchley, N.; Hotopf, M.; Hull, L.; Palmer, I.; Unwin, C.; David, A.; Wessely, S.

2000-01-01

OBJECTIVES—To study the association between occupational factors specific to the Armed Forces (rank, functional roles, Service, regular or reservist status and deployment factors) and symptomatic health problems in Gulf veterans, after sociodemographic and lifestyle factors have been accounted for.
DESIGN—A postal cross sectional survey of randomly selected UK Gulf veterans was conducted six to seven years after the Gulf conflict. Physical ill health was measured using the Fatigue Questionnaire and a measure of the Centers for Disease Control and Prevention (CDC) multi-symptom syndrome. Psychological ill health was measured using the General Health Questionnaire and a post-traumatic stress measure.
SETTING—Population of servicemen who were serving in the UK Armed Forces during the Gulf conflict between 1 September 1990 and 30 June 1991.
PARTICIPANTS—3297 Gulf veterans.
MAIN RESULTS—In multivariate logistic regression, there was an inverse relation between higher rank and psychological and physical ill health (test of trend: General Health Questionnaire, p=0.004 ; post-traumatic stress, p=0.002; fatigue, p=0.015; CDC case, p=0.002). Having left the Armed Forces was associated with a two to three times increase in reporting ill health. Of the deployment factors, there was a weak association between being deployed as an individual reinforcement in a combat role and post-traumatic stress but there was no association between receiving pre-deployment training or post-deployment leave and ill health. Marital status and smoking were associated with psychological and physical ill health.
CONCLUSIONS—Rank was the main occupational factor associated with both psychological and physical ill health in Gulf veterans. This may parallel the associations between socioeconomic status and morbidity in civilian populations. Ill health seems to be greater in those who return to civilian life. Sociodemographic factors also seem to be important in ill health in Gulf veterans.


Keywords: military; Gulf veterans; rank PMID:11027197

Multimodal decoding and congruent sensory information enhance reaching performance in subjects with cervical spinal cord injury.

PubMed

Corbett, Elaine A; Sachs, Nicholas A; Körding, Konrad P; Perreault, Eric J

2014-01-01

Cervical spinal cord injury (SCI) paralyzes muscles of the hand and arm, making it difficult to perform activities of daily living. Restoring the ability to reach can dramatically improve quality of life for people with cervical SCI. Any reaching system requires a user interface to decode parameters of an intended reach, such as trajectory and target. A challenge in developing such decoders is that often few physiological signals related to the intended reach remain under voluntary control, especially in patients with high cervical injuries. Furthermore, the decoding problem changes when the user is controlling the motion of their limb, as opposed to an external device. The purpose of this study was to investigate the benefits of combining disparate signal sources to control reach in people with a range of impairments, and to consider the effect of two feedback approaches. Subjects with cervical SCI performed robot-assisted reaching, controlling trajectories with either shoulder electromyograms (EMGs) or EMGs combined with gaze. We then evaluated how reaching performance was influenced by task-related sensory feedback, testing the EMG-only decoder in two conditions. The first involved moving the arm with the robot, providing congruent sensory feedback through their remaining sense of proprioception. In the second, the subjects moved the robot without the arm attached, as in applications that control external devices. We found that the multimodal-decoding algorithm worked well for all subjects, enabling them to perform straight, accurate reaches. The inclusion of gaze information, used to estimate target location, was especially important for the most impaired subjects. In the absence of gaze information, congruent sensory feedback improved performance. These results highlight the importance of proprioceptive feedback, and suggest that multi-modal decoders are likely to be most beneficial for highly impaired subjects and in tasks where such feedback is unavailable.

Wireless Sensor Network Optimization: Multi-Objective Paradigm.

PubMed

Iqbal, Muhammad; Naeem, Muhammad; Anpalagan, Alagan; Ahmed, Ashfaq; Azam, Muhammad

2015-07-20

Optimization problems relating to wireless sensor network planning, design, deployment and operation often give rise to multi-objective optimization formulations where multiple desirable objectives compete with each other and the decision maker has to select one of the tradeoff solutions. These multiple objectives may or may not conflict with each other. Keeping in view the nature of the application, the sensing scenario and input/output of the problem, the type of optimization problem changes. To address different nature of optimization problems relating to wireless sensor network design, deployment, operation, planing and placement, there exist a plethora of optimization solution types. We review and analyze different desirable objectives to show whether they conflict with each other, support each other or they are design dependent. We also present a generic multi-objective optimization problem relating to wireless sensor network which consists of input variables, required output, objectives and constraints. A list of constraints is also presented to give an overview of different constraints which are considered while formulating the optimization problems in wireless sensor networks. Keeping in view the multi facet coverage of this article relating to multi-objective optimization, this will open up new avenues of research in the area of multi-objective optimization relating to wireless sensor networks.

Small-angle X-ray Solution Scattering Study of the Multi-aminoacyl-tRNA Synthetase Complex Reveals an Elongated and Multi-armed particle*

PubMed Central

Dias, José; Renault, Louis; Pérez, Javier; Mirande, Marc

2013-01-01

In animal cells, nine aminoacyl-tRNA synthetases are associated with the three auxiliary proteins p18, p38, and p43 to form a stable and conserved large multi-aminoacyl-tRNA synthetase complex (MARS), whose molecular mass has been proposed to be between 1.0 and 1.5 MDa. The complex acts as a molecular hub for coordinating protein synthesis and diverse regulatory signal pathways. Electron microscopy studies defined its low resolution molecular envelope as an overall rather compact, asymmetric triangular shape. Here, we have analyzed the composition and homogeneity of the native mammalian MARS isolated from rabbit liver and characterized its overall internal structure, size, and shape at low resolution by hydrodynamic methods and small-angle x-ray scattering in solution. Our data reveal that the MARS exhibits a much more elongated and multi-armed shape than expected from previous reports. The hydrodynamic and structural features of the MARS are large compared with other supramolecular assemblies involved in translation, including ribosome. The large dimensions and non-compact structural organization of MARS favor a large protein surface accessibility for all its components. This may be essential to allow structural rearrangements between the catalytic and cis-acting tRNA binding domains of the synthetases required for binding the bulky tRNA substrates. This non-compact architecture may also contribute to the spatiotemporal controlled release of some of its components, which participate in non-canonical functions after dissociation from the complex. PMID:23836901

Multi-Armed RCTs: A Design-Based Framework. NCEE 2017-4027

ERIC Educational Resources Information Center

Schochet, Peter Z.

2017-01-01

Design-based methods have recently been developed as a way to analyze data from impact evaluations of interventions, programs, and policies (Imbens and Rubin, 2015; Schochet, 2015, 2016). The estimators are derived using the building blocks of experimental designs with minimal assumptions, and are unbiased and normally distributed in large samples…

Effects of PREPARE, a Multi-component, School-Based HIV and Intimate Partner Violence (IPV) Prevention Programme on Adolescent Sexual Risk Behaviour and IPV: Cluster Randomised Controlled Trial.

PubMed

Mathews, Catherine; Eggers, Sander M; Townsend, Loraine; Aarø, Leif E; de Vries, Petrus J; Mason-Jones, Amanda J; De Koker, Petra; McClinton Appollis, Tracy; Mtshizana, Yolisa; Koech, Joy; Wubs, Annegreet; De Vries, Hein

2016-09-01

Young South Africans, especially women, are at high risk of HIV. We evaluated the effects of PREPARE, a multi-component, school-based HIV prevention intervention to delay sexual debut, increase condom use and decrease intimate partner violence (IPV) among young adolescents. We conducted a cluster RCT among Grade eights in 42 high schools. The intervention comprised education sessions, a school health service and a school sexual violence prevention programme. Participants completed questionnaires at baseline, 6 and 12 months. Regression was undertaken to provide ORs or coefficients adjusted for clustering. Of 6244 sampled adolescents, 55.3 % participated. At 12 months there were no differences between intervention and control arms in sexual risk behaviours. Participants in the intervention arm were less likely to report IPV victimisation (35.1 vs. 40.9 %; OR 0.77, 95 % CI 0.61-0.99; t(40) = 2.14) suggesting the intervention shaped intimate partnerships into safer ones, potentially lowering the risk for HIV.

Model-based sensorimotor integration for multi-joint control: development of a virtual arm model.

PubMed

Song, D; Lan, N; Loeb, G E; Gordon, J

2008-06-01

An integrated, sensorimotor virtual arm (VA) model has been developed and validated for simulation studies of control of human arm movements. Realistic anatomical features of shoulder, elbow and forearm joints were captured with a graphic modeling environment, SIMM. The model included 15 musculotendon elements acting at the shoulder, elbow and forearm. Muscle actions on joints were evaluated by SIMM generated moment arms that were matched to experimentally measured profiles. The Virtual Muscle (VM) model contained appropriate admixture of slow and fast twitch fibers with realistic physiological properties for force production. A realistic spindle model was embedded in each VM with inputs of fascicle length, gamma static (gamma(stat)) and dynamic (gamma(dyn)) controls and outputs of primary (I(a)) and secondary (II) afferents. A piecewise linear model of Golgi Tendon Organ (GTO) represented the ensemble sampling (I(b)) of the total muscle force at the tendon. All model components were integrated into a Simulink block using a special software tool. The complete VA model was validated with open-loop simulation at discrete hand positions within the full range of alpha and gamma drives to extrafusal and intrafusal muscle fibers. The model behaviors were consistent with a wide variety of physiological phenomena. Spindle afferents were effectively modulated by fusimotor drives and hand positions of the arm. These simulations validated the VA model as a computational tool for studying arm movement control. The VA model is available to researchers at website http://pt.usc.edu/cel .

Surgical Lasers In Gynecology

NASA Astrophysics Data System (ADS)

Schellhas, Helmut F.; Barnes, Alfonso E.

1982-12-01

Multipurpose surgical CO2 lasers marketed in the USA have been developed to be applicable to a variety of surgical procedures in many surgical fields. They are all suited for endoscopic surgical procedures and can be fitted to all standard surgical microscopes. They all can adjust the focal length of the laser beam to the different standard focal lengths of the surgical microscope which for instance in laryngoscopy is 400 mm and in colposcopy 300 mm. One laser instrument can even change the spot size in a given focal distance which is very advantageous for some microsurgical procedures (Merrimack Laboratories 820). All multipurpose surgical CO2 laser systems provide a multi-articulated surgical arm for free-hand surgery. The surgical arms are cumbersome to use but they are adapted to the surgeons needs with ingenuity. The practicality of the multi-articulated surgical arms depends mostly on the distance of the handpiece from the surgical console which now is also overbridged by the laser tube in most surgical laser system. The spot size of the beam is variable in most handpieces by interchangeable lenses which modify the focal distance of the beam and the power density. Another common feature in all systems is a coaxial He-Ne pilot light which provides a red spot which unfortunately becomes invisible in a bleeding surgical field. Most surgical laser systems have a spacial mode of TEM 00 which is essential for incisional surgery. The continuous mode of beam delivery is used for incisional surgery and also for most endoscopic procedures.

Strategy of arm movement control is determined by minimization of neural effort for joint coordination.

PubMed

Dounskaia, Natalia; Shimansky, Yury

2016-06-01

Optimality criteria underlying organization of arm movements are often validated by testing their ability to adequately predict hand trajectories. However, kinematic redundancy of the arm allows production of the same hand trajectory through different joint coordination patterns. We therefore consider movement optimality at the level of joint coordination patterns. A review of studies of multi-joint movement control suggests that a 'trailing' pattern of joint control is consistently observed during which a single ('leading') joint is rotated actively and interaction torque produced by this joint is the primary contributor to the motion of the other ('trailing') joints. A tendency to use the trailing pattern whenever the kinematic redundancy is sufficient and increased utilization of this pattern during skillful movements suggests optimality of the trailing pattern. The goal of this study is to determine the cost function minimization of which predicts the trailing pattern. We show that extensive experimental testing of many known cost functions cannot successfully explain optimality of the trailing pattern. We therefore propose a novel cost function that represents neural effort for joint coordination. That effort is quantified as the cost of neural information processing required for joint coordination. We show that a tendency to reduce this 'neurocomputational' cost predicts the trailing pattern and that the theoretically developed predictions fully agree with the experimental findings on control of multi-joint movements. Implications for future research of the suggested interpretation of the trailing joint control pattern and the theory of joint coordination underlying it are discussed.

Do stigma and other perceived barriers to mental health care differ across Armed Forces?

PubMed Central

Gould, Matthew; Adler, Amy; Zamorski, Mark; Castro, Carl; Hanily, Natalie; Steele, Nicole; Kearney, Steve; Greenberg, Neil

2010-01-01

Summary Objectives Military organizations are keen to address barriers to mental health care yet stigma and barriers to care remain little understood, especially potential cultural differences between Armed Forces. The aim of this study was to compare data collected by the US, UK, Australian, New Zealand and Canadian militaries using Hoge et al.'s perceived stigma and barriers to care measure (Combat duty in Iraq and Afghanistan, mental health problems and barriers to care. New Engl J Med 2004;351:13–22). Design Each member country identified data sources that had enquired about Hoge et al.'s perceived stigma and perceived barriers to care items in the re-deployment or immediate post-deployment period. Five relevant statements were included in the study. Setting US, UK Australian, New Zealand and Canadian Armed Forces. Results Concerns about stigma and barriers to care tended to be more prominent among personnel who met criteria for a mental health problem. The pattern of reported stigma and barriers to care was similar across the Armed Forces of all five nations. Conclusions Barriers to care continue to be a major issue for service personnel within Western military forces. Although there are policy, procedural and cultural differences between Armed Forces, the nations studied appear to share some similarities in terms of perceived stigma and barriers to psychological care. Further research to understand patterns of reporting and subgroup differences is required. PMID:20382906

An enhanced flexible dynamic model and experimental verification for a valve train with clearance and multi-directional deformations

NASA Astrophysics Data System (ADS)

Zhou, Changjiang; Hu, Bo; Chen, Siyu; He, Liping

2017-12-01

An enhanced flexible dynamic model for a valve train with clearance and multi-directional deformations is proposed based on finite element method (FEM), and verified by experiment. According to the measured cam profile, the available internal excitations in numerical solution to the model are achieved by using piecewise cubic Hermite interpolating polynomial. The comparative analysis demonstrates that the bending deformation of the rocker arm is much larger than the radial deformation, signifying the necessities of multi-directional deformations in dynamic analysis for the valve train. The effects of valve clearance and cam rotation speed on contact force, acceleration and dynamic transmission error (DTE) are investigated. Both theoretical predictions and experimental measurements show that the amplitudes and fluctuations of contact force, acceleration and DTE become larger, when the valve clearance or cam speed increases. It is found that including the elasticity and the damping will weaken the impact between the rocker arm and the valve on the components (not adjacent to the valve) at either unseating or seating scenario. Additionally, as valve clearance or cam rotation speed becomes larger, the valve lift and the working phase decrease, which eventually leads to inlet air reduction. Furthermore, our study shows that the combustion rate improvement, input torque, and components durability can be improved by tuning valve clearance or adjustment the cam profile.

Multi-kilobase homozygous targeted gene replacement in human induced pluripotent stem cells.

PubMed

Byrne, Susan M; Ortiz, Luis; Mali, Prashant; Aach, John; Church, George M

2015-02-18

Sequence-specific nucleases such as TALEN and the CRISPR/Cas9 system have so far been used to disrupt, correct or insert transgenes at precise locations in mammalian genomes. We demonstrate efficient 'knock-in' targeted replacement of multi-kilobase genes in human induced pluripotent stem cells (iPSC). Using a model system replacing endogenous human genes with their mouse counterpart, we performed a comprehensive study of targeting vector design parameters for homologous recombination. A 2.7 kilobase (kb) homozygous gene replacement was achieved in up to 11% of iPSC without selection. The optimal homology arm length was around 2 kb, with homology length being especially critical on the arm not adjacent to the cut site. Homologous sequence inside the cut sites was detrimental to targeting efficiency, consistent with a synthesis-dependent strand annealing (SDSA) mechanism. Using two nuclease sites, we observed a high degree of gene excisions and inversions, which sometimes occurred more frequently than indel mutations. While homozygous deletions of 86 kb were achieved with up to 8% frequency, deletion frequencies were not solely a function of nuclease activity and deletion size. Our results analyzing the optimal parameters for targeting vector design will inform future gene targeting efforts involving multi-kilobase gene segments, particularly in human iPSC. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Kinematic synthesis of adjustable robotic mechanisms

NASA Astrophysics Data System (ADS)

Chuenchom, Thatchai

1993-01-01

Conventional hard automation, such as a linkage-based or a cam-driven system, provides high speed capability and repeatability but not the flexibility required in many industrial applications. The conventional mechanisms, that are typically single-degree-of-freedom systems, are being increasingly replaced by multi-degree-of-freedom multi-actuators driven by logic controllers. Although this new trend in sophistication provides greatly enhanced flexibility, there are many instances where the flexibility needs are exaggerated and the associated complexity is unnecessary. Traditional mechanism-based hard automation, on the other hand, neither can fulfill multi-task requirements nor are cost-effective mainly due to lack of methods and tools to design-in flexibility. This dissertation attempts to bridge this technological gap by developing Adjustable Robotic Mechanisms (ARM's) or 'programmable mechanisms' as a middle ground between high speed hard automation and expensive serial jointed-arm robots. This research introduces the concept of adjustable robotic mechanisms towards cost-effective manufacturing automation. A generalized analytical synthesis technique has been developed to support the computational design of ARM's that lays the theoretical foundation for synthesis of adjustable mechanisms. The synthesis method developed in this dissertation, called generalized adjustable dyad and triad synthesis, advances the well-known Burmester theory in kinematics to a new level. While this method provides planar solutions, a novel patented scheme is utilized for converting prescribed three-dimensional motion specifications into sets of planar projections. This provides an analytical and a computational tool for designing adjustable mechanisms that satisfy multiple sets of three-dimensional motion specifications. Several design issues were addressed, including adjustable parameter identification, branching defect, and mechanical errors. An efficient mathematical scheme for identification of adjustable member was also developed. The analytical synthesis techniques developed in this dissertation were successfully implemented in a graphic-intensive user-friendly computer program. A physical prototype of a general purpose adjustable robotic mechanism has been constructed to serve as a proof-of-concept model.

Multi-armed poly(L-glutamic acid)-graft-oligoethylenimine copolymers as efficient nonviral gene delivery vectors.

PubMed

Chen, Lei; Tian, Huayu; Chen, Jie; Chen, Xuesi; Huang, Yubin; Jing, Xiabin

2010-01-01

The application of polyethylenimine (PEI) in gene delivery has been severely limited by significant cytotoxicity that results from a nondegradable methylene backbone and high cationic charge density. It is therefore necessary to develop novel biodegradable PEI derivates for low-toxic, highly efficient gene delivery. A series of novel cationic copolymers with various charge density were designed and synthesized by grafting different kinds of oligoethylenimine (OEI) onto a determinate multi-armed poly(L-glutamic acid) backbone. The molecular structures of multi-armed poly(L-glutamic acid)-graft-OEI (MP-g-OEI) copolymers were characterized using nuclear magnetic resonance, viscosimetry and gel permeation chromatography. Moreover, the MP-g-OEI/DNA complexes were measured by a gel retardation assay, dynamic light scattering and atomic force microscopy to determine DNA binding ability, particle size, zeta potential, complex formation and shape, respectively. MP-g-OEI copolymers were also evaluated in Chinese hamster ovary and human embryonic kidney-293 cells for their cytotoxicity and transfection efficiency. The particle sizes of MP-g-OEI/DNA complexes were in a range of 109.6-182.6 nm and the zeta potentials were in a range of 29.2-44.5 mV above the N/P ratio of 5. All the MP-g-OEI copolymers exhibited lower cytotoxicity and higher gene transfection efficiency than PEI25k in the absence and presence of serum with different cell lines. Importantly, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay revealed that the cytotoxicity of MP-g-OEI copolymers varied with their molecular weight and charge density, and two of MP-g-OEI copolymers (OEI600-MP and OEI1800-MP) could achieve optimal transfection efficiency at a similar low N/P ratio as that for PEI25k. MP-g-OEI copolymers demonstrated considerable potential as nonviral vectors for gene therapy. Copyright 2009 John Wiley & Sons, Ltd.

Distributed consensus for discrete-time heterogeneous multi-agent systems

NASA Astrophysics Data System (ADS)

Zhao, Huanyu; Fei, Shumin

2018-06-01

This paper studies the consensus problem for a class of discrete-time heterogeneous multi-agent systems. Two kinds of consensus algorithms will be considered. The heterogeneous multi-agent systems considered are converted into equivalent error systems by a model transformation. Then we analyse the consensus problem of the original systems by analysing the stability problem of the error systems. Some sufficient conditions for consensus of heterogeneous multi-agent systems are obtained by applying algebraic graph theory and matrix theory. Simulation examples are presented to show the usefulness of the results.

A systematic review on the mental health of children and adolescents in areas of armed conflict in the Middle East.

PubMed

Dimitry, L

2012-03-01

For many decades, the Middle East has been troubled with numerous long-standing armed conflicts and wars. Children and adolescents were not spared the trauma and its consequences. Exposure to traumatic events can result in mental, behavioural and emotional problems in children and adolescents. To date, this is the first paper that aims to systematically review the literature on the mental health of children and adolescents living in areas of armed conflict in the Middle East, specifically Israel, Palestine, Lebanon and Iraq. It explores factors that mediate between exposure to armed conflict and mental, behavioural and emotional problems and places them in a cultural context. Pubmed was searched and papers were identified using specific inclusion criteria. Seventy-one eligible studies were included. The main findings are that children and adolescents living in these conflict zones are exposed to high levels of traumatic experiences. Number of conflict-related traumatic experiences correlates positively with prevalence of mental, behavioural and emotional problems. Prevalence of post-traumatic stress disorder in children and adolescents is estimated to be 5-8% in Israel, 23-70% in Palestine and 10-30% in Iraq (insufficient data for Lebanon). The main determining factors identified were level and type of exposure, age, gender, socio-economic adversity, social support and religiosity. These findings bring to light the pressing need to provide children and adolescents living in conflict areas with help. They are useful in designing new interventions to strengthen child and adolescent resilience in areas of conflict worldwide. Specific recommendations are included. © 2011 Blackwell Publishing Ltd.

Connected Component Model for Multi-Object Tracking.

PubMed

He, Zhenyu; Li, Xin; You, Xinge; Tao, Dacheng; Tang, Yuan Yan

2016-08-01

In multi-object tracking, it is critical to explore the data associations by exploiting the temporal information from a sequence of frames rather than the information from the adjacent two frames. Since straightforwardly obtaining data associations from multi-frames is an NP-hard multi-dimensional assignment (MDA) problem, most existing methods solve this MDA problem by either developing complicated approximate algorithms, or simplifying MDA as a 2D assignment problem based upon the information extracted only from adjacent frames. In this paper, we show that the relation between associations of two observations is the equivalence relation in the data association problem, based on the spatial-temporal constraint that the trajectories of different objects must be disjoint. Therefore, the MDA problem can be equivalently divided into independent subproblems by equivalence partitioning. In contrast to existing works for solving the MDA problem, we develop a connected component model (CCM) by exploiting the constraints of the data association and the equivalence relation on the constraints. Based upon CCM, we can efficiently obtain the global solution of the MDA problem for multi-object tracking by optimizing a sequence of independent data association subproblems. Experiments on challenging public data sets demonstrate that our algorithm outperforms the state-of-the-art approaches.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51269 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm (out of frame) grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth. Discovery's vertical stabilizer is at left.

Design and multi-physics optimization of rotary MRF brakes

NASA Astrophysics Data System (ADS)

Topcu, Okan; Taşcıoğlu, Yiğit; Konukseven, Erhan İlhan

2018-03-01

Particle swarm optimization (PSO) is a popular method to solve the optimization problems. However, calculations for each particle will be excessive when the number of particles and complexity of the problem increases. As a result, the execution speed will be too slow to achieve the optimized solution. Thus, this paper proposes an automated design and optimization method for rotary MRF brakes and similar multi-physics problems. A modified PSO algorithm is developed for solving multi-physics engineering optimization problems. The difference between the proposed method and the conventional PSO is to split up the original single population into several subpopulations according to the division of labor. The distribution of tasks and the transfer of information to the next party have been inspired by behaviors of a hunting party. Simulation results show that the proposed modified PSO algorithm can overcome the problem of heavy computational burden of multi-physics problems while improving the accuracy. Wire type, MR fluid type, magnetic core material, and ideal current inputs have been determined by the optimization process. To the best of the authors' knowledge, this multi-physics approach is novel for optimizing rotary MRF brakes and the developed PSO algorithm is capable of solving other multi-physics engineering optimization problems. The proposed method has showed both better performance compared to the conventional PSO and also has provided small, lightweight, high impedance rotary MRF brake designs.

Enhancing Human Resource Capability in the Tanzania Peoples Defense Force (TPDF)

DTIC Science & Technology

2006-06-01

Tanzania’s elephants , thus making the Selous a big attraction to tourists (Pan- African News Agency, 1999). The problem of poaching is not only confined...the Cold War and the collapse of the Soviet Union changed the strategic environment. Refugees from conflict torn areas, poaching , small arms...changed the strategic environment. Refugees from conflict torn areas, poaching , small arms proliferation, political and religious fundamentalism, drug

USSR Report, International Affairs

DTIC Science & Technology

1987-04-22

base at Greenham Common, where British women are now spending their fifth winter besieging the cruise missile stockpiles. It is going on in the court...Counterstrategy to the Plans for Preparing for War and the Buildup in the Arms Race"), R. Prasad ( India ) ("The Socioeconoraic Consequences of the Arms...The International Peace Institute in Vienna), D. ( Dalits ) (the UN Institute for Studying Disarmament Problems), and others attending the forum was

Wireless Sensor Network Optimization: Multi-Objective Paradigm

PubMed Central

Iqbal, Muhammad; Naeem, Muhammad; Anpalagan, Alagan; Ahmed, Ashfaq; Azam, Muhammad

2015-01-01

Optimization problems relating to wireless sensor network planning, design, deployment and operation often give rise to multi-objective optimization formulations where multiple desirable objectives compete with each other and the decision maker has to select one of the tradeoff solutions. These multiple objectives may or may not conflict with each other. Keeping in view the nature of the application, the sensing scenario and input/output of the problem, the type of optimization problem changes. To address different nature of optimization problems relating to wireless sensor network design, deployment, operation, planing and placement, there exist a plethora of optimization solution types. We review and analyze different desirable objectives to show whether they conflict with each other, support each other or they are design dependent. We also present a generic multi-objective optimization problem relating to wireless sensor network which consists of input variables, required output, objectives and constraints. A list of constraints is also presented to give an overview of different constraints which are considered while formulating the optimization problems in wireless sensor networks. Keeping in view the multi facet coverage of this article relating to multi-objective optimization, this will open up new avenues of research in the area of multi-objective optimization relating to wireless sensor networks. PMID:26205271

A multi-valued neutrosophic qualitative flexible approach based on likelihood for multi-criteria decision-making problems

NASA Astrophysics Data System (ADS)

Peng, Juan-juan; Wang, Jian-qiang; Yang, Wu-E.

2017-01-01

In this paper, multi-criteria decision-making (MCDM) problems based on the qualitative flexible multiple criteria method (QUALIFLEX), in which the criteria values are expressed by multi-valued neutrosophic information, are investigated. First, multi-valued neutrosophic sets (MVNSs), which allow the truth-membership function, indeterminacy-membership function and falsity-membership function to have a set of crisp values between zero and one, are introduced. Then the likelihood of multi-valued neutrosophic number (MVNN) preference relations is defined and the corresponding properties are also discussed. Finally, an extended QUALIFLEX approach based on likelihood is explored to solve MCDM problems where the assessments of alternatives are in the form of MVNNs; furthermore an example is provided to illustrate the application of the proposed method, together with a comparison analysis.

Finger muscle attachments for an OpenSim upper-extremity model.

PubMed

Lee, Jong Hwa; Asakawa, Deanna S; Dennerlein, Jack T; Jindrich, Devin L

2015-01-01

We determined muscle attachment points for the index, middle, ring and little fingers in an OpenSim upper-extremity model. Attachment points were selected to match both experimentally measured locations and mechanical function (moment arms). Although experimental measurements of finger muscle attachments have been made, models differ from specimens in many respects such as bone segment ratio, joint kinematics and coordinate system. Likewise, moment arms are not available for all intrinsic finger muscles. Therefore, it was necessary to scale and translate muscle attachments from one experimental or model environment to another while preserving mechanical function. We used a two-step process. First, we estimated muscle function by calculating moment arms for all intrinsic and extrinsic muscles using the partial velocity method. Second, optimization using Simulated Annealing and Hooke-Jeeves algorithms found muscle-tendon paths that minimized root mean square (RMS) differences between experimental and modeled moment arms. The partial velocity method resulted in variance accounted for (VAF) between measured and calculated moment arms of 75.5% on average (range from 48.5% to 99.5%) for intrinsic and extrinsic index finger muscles where measured data were available. RMS error between experimental and optimized values was within one standard deviation (S.D) of measured moment arm (mean RMS error = 1.5 mm < measured S.D = 2.5 mm). Validation of both steps of the technique allowed for estimation of muscle attachment points for muscles whose moment arms have not been measured. Differences between modeled and experimentally measured muscle attachments, averaged over all finger joints, were less than 4.9 mm (within 7.1% of the average length of the muscle-tendon paths). The resulting non-proprietary musculoskeletal model of the human fingers could be useful for many applications, including better understanding of complex multi-touch and gestural movements.

Finger Muscle Attachments for an OpenSim Upper-Extremity Model

PubMed Central

Lee, Jong Hwa; Asakawa, Deanna S.; Dennerlein, Jack T.; Jindrich, Devin L.

2015-01-01

We determined muscle attachment points for the index, middle, ring and little fingers in an OpenSim upper-extremity model. Attachment points were selected to match both experimentally measured locations and mechanical function (moment arms). Although experimental measurements of finger muscle attachments have been made, models differ from specimens in many respects such as bone segment ratio, joint kinematics and coordinate system. Likewise, moment arms are not available for all intrinsic finger muscles. Therefore, it was necessary to scale and translate muscle attachments from one experimental or model environment to another while preserving mechanical function. We used a two-step process. First, we estimated muscle function by calculating moment arms for all intrinsic and extrinsic muscles using the partial velocity method. Second, optimization using Simulated Annealing and Hooke-Jeeves algorithms found muscle-tendon paths that minimized root mean square (RMS) differences between experimental and modeled moment arms. The partial velocity method resulted in variance accounted for (VAF) between measured and calculated moment arms of 75.5% on average (range from 48.5% to 99.5%) for intrinsic and extrinsic index finger muscles where measured data were available. RMS error between experimental and optimized values was within one standard deviation (S.D) of measured moment arm (mean RMS error = 1.5 mm < measured S.D = 2.5 mm). Validation of both steps of the technique allowed for estimation of muscle attachment points for muscles whose moment arms have not been measured. Differences between modeled and experimentally measured muscle attachments, averaged over all finger joints, were less than 4.9 mm (within 7.1% of the average length of the muscle-tendon paths). The resulting non-proprietary musculoskeletal model of the human fingers could be useful for many applications, including better understanding of complex multi-touch and gestural movements. PMID:25853869

The PdBI Arcsecond Whirlpool Survey (PAWS): The Role of Spiral Arms in Cloud and Star Formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schinnerer, Eva; Meidt, Sharon E.; Querejeta, Miguel

2017-02-10

The process that leads to the formation of the bright star-forming sites observed along prominent spiral arms remains elusive. We present results of a multi-wavelength study of a spiral arm segment in the nearby grand-design spiral galaxy M51 that belongs to a spiral density wave and exhibits nine gas spurs. The combined observations of the (ionized, atomic, molecular, dusty) interstellar medium with star formation tracers (H ii regions, young <10 Myr stellar clusters) suggest (1) no variation in giant molecular cloud (GMC) properties between arm and gas spurs, (2) gas spurs and extinction feathers arising from the same structure withmore » a close spatial relation between gas spurs and ongoing/recent star formation (despite higher gas surface densities in the spiral arm), (3) no trend in star formation age either along the arm or along a spur, (4) evidence for strong star formation feedback in gas spurs, (5) tentative evidence for star formation triggered by stellar feedback for one spur, and (6) GMC associations being not special entities but the result of blending of gas arm/spur cross sections in lower resolution observations. We conclude that there is no evidence for a coherent star formation onset mechanism that can be solely associated with the presence of the spiral density wave. This suggests that other (more localized) mechanisms are important to delay star formation such that it occurs in spurs. The evidence of star formation proceeding over several million years within individual spurs implies that the mechanism that leads to star formation acts or is sustained over a longer timescale.« less

Modelling of loading, stress relaxation and stress recovery in a shape memory polymer.

PubMed

Sweeney, J; Bonner, M; Ward, I M

2014-09-01

A multi-element constitutive model for a lactide-based shape memory polymer has been developed that represents loading to large tensile deformations, stress relaxation and stress recovery at 60, 65 and 70°C. The model consists of parallel Maxwell arms each comprising neo-Hookean and Eyring elements. Guiu-Pratt analysis of the stress relaxation curves yields Eyring parameters. When these parameters are used to define the Eyring process in a single Maxwell arm, the resulting model yields at too low a stress, but gives good predictions for longer times. Stress dip tests show a very stiff response on unloading by a small strain decrement. This would create an unrealistically high stress on loading to large strain if it were modelled by an elastic element. Instead it is modelled by an Eyring process operating via a flow rule that introduces strain hardening after yield. When this process is incorporated into a second parallel Maxwell arm, there results a model that fully represents both stress relaxation and stress dip tests at 60°C. At higher temperatures a third arm is required for valid predictions. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

An ARM data-oriented diagnostics package to evaluate the climate model simulation

NASA Astrophysics Data System (ADS)

Zhang, C.; Xie, S.

2016-12-01

A set of diagnostics that utilize long-term high frequency measurements from the DOE Atmospheric Radiation Measurement (ARM) program is developed for evaluating the regional simulation of clouds, radiation and precipitation in climate models. The diagnostics results are computed and visualized automatically in a python-based package that aims to serve as an easy entry point for evaluating climate simulations using the ARM data, as well as the CMIP5 multi-model simulations. Basic performance metrics are computed to measure the accuracy of mean state and variability of simulated regional climate. The evaluated physical quantities include vertical profiles of clouds, temperature, relative humidity, cloud liquid water path, total column water vapor, precipitation, sensible and latent heat fluxes, radiative fluxes, aerosol and cloud microphysical properties. Process-oriented diagnostics focusing on individual cloud and precipitation-related phenomena are developed for the evaluation and development of specific model physical parameterizations. Application of the ARM diagnostics package will be presented in the AGU session. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, IM release number is: LLNL-ABS-698645.

ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) Field Campaign Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leung, L Ruby

The U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility’s ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) field campaign contributes to CalWater 2015, a multi-agency field campaign that aims to improve understanding of atmospheric rivers and aerosol sources and transport that influence cloud and precipitation processes. The ultimate goal is to reduce uncertainties in weather predictions and climate projections of droughts and floods in California. With the DOE G-1 aircraft and ARM Mobile Facility 2 (AMF2) well equipped for making aerosol and cloud measurements, ACAPEX focuses specifically on understanding how aerosols from local pollution and long-range transport affect the amountmore » and phase of precipitation associated with atmospheric rivers. ACAPEX took place between January 12, 2015 and March 8, 2015 as part of CalWater 2015, which included four aircraft (DOE G-1, National Oceanic and Atmospheric Administration [NOAA] G-IV and P-3, and National Aeronautics and Space Administration [NASA] ER-2), the NOAA research ship Ron Brown, carrying onboard the AMF2, National Science Foundation (NSF)-sponsored aerosol and precipitation measurements at Bodega Bay, and the California Department of Water Resources extreme precipitation network.« less

Multi-Scale/Multi-Functional Probabilistic Composite Fatigue

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2008-01-01

A multi-level (multi-scale/multi-functional) evaluation is demonstrated by applying it to three different sample problems. These problems include the probabilistic evaluation of a space shuttle main engine blade, an engine rotor and an aircraft wing. The results demonstrate that the blade will fail at the highest probability path, the engine two-stage rotor will fail by fracture at the rim and the aircraft wing will fail at 109 fatigue cycles with a probability of 0.9967.

Towards large scale multi-target tracking

NASA Astrophysics Data System (ADS)

Vo, Ba-Ngu; Vo, Ba-Tuong; Reuter, Stephan; Lam, Quang; Dietmayer, Klaus

2014-06-01

Multi-target tracking is intrinsically an NP-hard problem and the complexity of multi-target tracking solutions usually do not scale gracefully with problem size. Multi-target tracking for on-line applications involving a large number of targets is extremely challenging. This article demonstrates the capability of the random finite set approach to provide large scale multi-target tracking algorithms. In particular it is shown that an approximate filter known as the labeled multi-Bernoulli filter can simultaneously track one thousand five hundred targets in clutter on a standard laptop computer.

Neural-Dynamic-Method-Based Dual-Arm CMG Scheme With Time-Varying Constraints Applied to Humanoid Robots.

PubMed

Zhang, Zhijun; Li, Zhijun; Zhang, Yunong; Luo, Yamei; Li, Yuanqing

2015-12-01

We propose a dual-arm cyclic-motion-generation (DACMG) scheme by a neural-dynamic method, which can remedy the joint-angle-drift phenomenon of a humanoid robot. In particular, according to a neural-dynamic design method, first, a cyclic-motion performance index is exploited and applied. This cyclic-motion performance index is then integrated into a quadratic programming (QP)-type scheme with time-varying constraints, called the time-varying-constrained DACMG (TVC-DACMG) scheme. The scheme includes the kinematic motion equations of two arms and the time-varying joint limits. The scheme can not only generate the cyclic motion of two arms for a humanoid robot but also control the arms to move to the desired position. In addition, the scheme considers the physical limit avoidance. To solve the QP problem, a recurrent neural network is presented and used to obtain the optimal solutions. Computer simulations and physical experiments demonstrate the effectiveness and the accuracy of such a TVC-DACMG scheme and the neural network solver.

Status of the VEGA Project

NASA Astrophysics Data System (ADS)

Kamanin, D. V.; Alexandrov, A. A.; Alexandrova, I. A.; Kondtatyev, N. A.; Kuznetsova, E. A.; Shvetsov, V. N.; Strekalovsky, A. O.; Strekalovsky, O. V.; Zhuchko, V. E.; Pyatkov, Yu. V.; Jacobs, N.; Malaza, V.

2015-06-01

Motivation and status of the VEGA (Velocity-Energy Guide based Array) project is presented. One armed fission fragments spectrometer with an electrostatic guide system is proposed for installation at the vertical experimental channel of the IBR-2 reactor. Scientific program aimed at investigation of new multi-body decays of actinides, shapeisomeric states in fission fragments and fission modes is reported.

78 FR 45017 - Amendment to the International Traffic in Arms Regulations: Revision of U.S. Munitions List...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-25

...)(i)(A) through (D), on the basis that commercial articles would otherwise be covered. The Department notes that the criteria in (A) through (D) are modified by the criteria of paragraph (a)(1)(i). However..., submarines, other undersea vehicles, torpedoes, or mines, having any of the following: (A) Multi-static...

Co-Labeling for Multi-View Weakly Labeled Learning.

PubMed

Xu, Xinxing; Li, Wen; Xu, Dong; Tsang, Ivor W

2016-06-01

It is often expensive and time consuming to collect labeled training samples in many real-world applications. To reduce human effort on annotating training samples, many machine learning techniques (e.g., semi-supervised learning (SSL), multi-instance learning (MIL), etc.) have been studied to exploit weakly labeled training samples. Meanwhile, when the training data is represented with multiple types of features, many multi-view learning methods have shown that classifiers trained on different views can help each other to better utilize the unlabeled training samples for the SSL task. In this paper, we study a new learning problem called multi-view weakly labeled learning, in which we aim to develop a unified approach to learn robust classifiers by effectively utilizing different types of weakly labeled multi-view data from a broad range of tasks including SSL, MIL and relative outlier detection (ROD). We propose an effective approach called co-labeling to solve the multi-view weakly labeled learning problem. Specifically, we model the learning problem on each view as a weakly labeled learning problem, which aims to learn an optimal classifier from a set of pseudo-label vectors generated by using the classifiers trained from other views. Unlike traditional co-training approaches using a single pseudo-label vector for training each classifier, our co-labeling approach explores different strategies to utilize the predictions from different views, biases and iterations for generating the pseudo-label vectors, making our approach more robust for real-world applications. Moreover, to further improve the weakly labeled learning on each view, we also exploit the inherent group structure in the pseudo-label vectors generated from different strategies, which leads to a new multi-layer multiple kernel learning problem. Promising results for text-based image retrieval on the NUS-WIDE dataset as well as news classification and text categorization on several real-world multi-view datasets clearly demonstrate that our proposed co-labeling approach achieves state-of-the-art performance for various multi-view weakly labeled learning problems including multi-view SSL, multi-view MIL and multi-view ROD.

Improving multi-objective reservoir operation optimization with sensitivity-informed dimension reduction

NASA Astrophysics Data System (ADS)

Chu, J.; Zhang, C.; Fu, G.; Li, Y.; Zhou, H.

2015-08-01

This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed method dramatically reduces the computational demands required for attaining high-quality approximations of optimal trade-off relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed dimension reduction and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform dimension reduction of optimization problems when solving complex multi-objective reservoir operation problems.

Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin

In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

DOE PAGES

Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin; ...

2017-07-08

In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

Increasing Childhood Influenza Vaccination

PubMed Central

Nowalk, Mary Patricia; Lin, Chyongchiou J.; Hannibal, Kristin; Reis, Evelyn C.; Gallik, Gregory; Moehling, Krissy K.; Huang, Hsin-Hui; Allred, Norma J.; Wolfson, David H.; Zimmerman, Richard K.

2014-01-01

Background Since the 2008 inception of universal childhood influenza vaccination, national rates have risen more dramatically among younger children than older children and reported rates across racial/ethnic groups are inconsistent. Interventions may be needed to address age and racial disparities to achieve the recommended childhood influenza vaccination target of 70%. Purpose To evaluate an intervention to increase childhood influenza vaccination across age and racial groups. Methods In 2011–2012, 20 primary care practices treating children were randomly assigned to Intervention and Control arms of a cluster randomized controlled trial to increase childhood influenza vaccination uptake using a toolkit and other strategies including early delivery of donated vaccine, in-service staff meetings, and publicity. Results The average vaccination differences from pre-intervention to the intervention year were significantly larger in the Intervention arm (n=10 practices) than the Control arm (n=10 practices), for children aged 2–8 years (10.2 percentage points (pct pts) Intervention vs 3.6 pct pts Control) and 9–18 years (11.1 pct pts Intervention vs 4.3 pct pts Control, p<0.05), for non-white children (16.7 pct pts Intervention vs 4.6 pct pts Control, p<0.001), and overall (9.9 pct pts Intervention vs 4.2 pct pts Control, p<0.01). In multi-level modeling that accounted for person- and practice-level variables and the interactions among age, race and intervention, the likelihood of vaccination increased with younger age group (6–23 months), white race, commercial insurance, the practice’s pre-intervention vaccination rate, and being in the Intervention arm. Estimates of the interaction terms indicated that the intervention increased the likelihood of vaccination for non-white children in all age groups and white children aged 9–18 years. Conclusions A multi-strategy intervention that includes a practice improvement toolkit can significantly improve influenza vaccination uptake across age and racial groups without targeting specific groups, especially in practices with large percentages of minority children. PMID:25113138

A Review of Pomegranate in Prostate Cancer

PubMed Central

Paller, Channing J.; Pantuck, Allan; Carducci, Michael A.

2017-01-01

Background Preclinical studies showing that pomegranate juice and its components inhibit prostate cancer led to multiple clinical trials to determine whether pomegranate products could slow the growth of prostate cancer. This review summarizes the preclinical data and discusses the results of the clinical trials. Methods Trials targeted patients on active surveillance, neoadjuvant patients, patients with biochemical recurrence (BCR) following local therapy for prostate cancer, and patients with metastatic castration-resistant prostate cancer (mCRPC). Results In the BCR patient population, early phase II trials of both pomegranate juice and extract showed significant lengthening of PSA doubling time (PSADT), and confirmed the safety of pomegranate products. While a placebo-controlled phase III trial determined that pomegranate extract did not significantly prolong PSADT in BCR patients, a preplanned subset analysis of patients with the manganese superoxide dismutase (MnSOD) AA genotype showed greater PSADT lengthening on the pomegranate extract arm. In the neoadjuvant population, a large trial demonstrated a significant increase in urolithin A and a non-significant reduction in 8-OHdG, a marker of oxidation in prostate cancer tissue, on the pomegranate arm vs. the placebo arm. In addition, a randomized clinical trial of a polyphenol-rich multi-component food supplement tablet, including 31.25% pomegranate extract, found significant slowing of PSA increase in the food supplement arm vs. placebo in men on active surveillance and those experiencing biochemical recurrence. Conclusions Pomegranate juice and extract are safe but did not significantly improve outcomes in BCR patients in a large placebo controlled trial. However a subset of BCR patients with the MnSOD AA genotype appear to respond positively to the antioxidant effects of pomegranate treatment. Phase II trials of 100% pomegranate products in neoadjuvant patients and patients with mCRPC were negative. A multi-component food supplement showed promising results in a phase II study in active surveillance and BCR patients. PMID:28440320

Instrumental research of lithodynamic processes in estuaries of the White Sea

NASA Astrophysics Data System (ADS)

Rimsky-Korsakov, Nikolai; Korotaev, Vladislav; Ivanov, Vadim

2017-04-01

The report provides a comparative analysis of morphological lithodynamic processes in estuaries and river deltas on the basis of 2013-2015 field geophysical and hydrographic surveys held by IO RAS and MSU. Studies performed using side scan sonar (Imagenex YellowFin SSS), bathymetric (FortXXI Scat Echo sounder) and navigation (DGPS/GLONASS Sigma Ashtek receiver) equipment. North Dvina modern delta can be classified as multi-arm delta estuary lagoon performance. Areas of modern river waters occupy a large accumulation of deltaic arms. It formed a young island with elevations of about 1 m. The islands are composed of river alluvium and annually flooded during the flood period. Onega river mouth area is unique due to the specific geological conditions. Short, wellhead site is the cause of the anomalous attenuation of the tidal wave and the limited range of penetration of salt water seashore only to Kokorinskogo threshold. Morphological lithodynamic processes in high tide Mezen estuaries (syzygy - 8.5 m) are caused by tidal currents, river runoff, wind waves and sediment longshore drift. Due to the movement of huge masses of sediment in the Mezen estuary occur intense deformation silty-sand banks, reshaping of the bottom channel trenches and displacement of navigable waterways. Thus, the specificity of the morphological lithodynamic processes in high tidal estuaries is a lack of modern delta, the development of mobile local sediment structures inside the estuary and the formation of a broad mouth bar on the open wellhead coast. In multi-arm deltas an intense process of increasing marine edge of the delta is observed due to wellhead delta arms elongation and the formation of small estuarine bars at the mouths of the underwater channel trenches coming out into the open coast. Simultaneously, the process of filling the river sediments of residual waters within the subaerial delta and the formation of marine coastal bars on the outer perimeter edge of the sea ground delta.

KSC-2010-1193

NASA Image and Video Library

2010-01-12

CAPE CANAVERAL, Fla. - In the Remote Manipulator System Lab inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' orbiter boom sensor system, or OBSS, awaits inspection. The 50-foot-long OBSS attaches to the end of the shuttle’s robotic arm and supports the cameras and laser systems used to inspect the shuttle’s thermal protection system while in space. Atlantis is next slated to deliver an Integrated Cargo Carrier and Russian-built Mini Research Module to the International Space Station on the STS-132 mission. The second in a series of new pressurized components for Russia, the module will be permanently attached to the Zarya module. Three spacewalks are planned to store spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-purpose Laboratory Module also are payloads on the flight. Launch is targeted for May 14, 2010. Photo credit: NASA/Jack Pfaller

STS-114 orbiter Discovery during docking of Raffaello

NASA Image and Video Library

2005-08-05

ISS011-E-11510 (5 August 2005) --- On the eve of the separation of Discovery and the International Space Station, an Expedition 11 crew member took this digital still picture. Crews onboard the orbital outpost and Discovery were wrapping up nine days of joint operations. The Space Shuttle is partially visible beneath other hardware. The Canadian-built robot arms for both spacecraft are dominant in the frame. A Russian Soyuz is docked to the Station in the foreground. After the Italian-built Multi-Purpose Logistics Module Raffaello was secured in Discovery's cargo bay, Astronauts Charles J. Camarda and Andrew S.W. Thomas, mission specialists operating from Discovery's aft flight deck, used the Shuttle arm to hand off the Orbiter Boom Sensor System to the Station arm. Then Astronauts Wendy B. Lawrence, mission specialist, and James M. Kelly, pilot, onboard Destiny, reberthed the OBSS in its position on the starboard sill of the cargo bay. Undocking is scheduled shortly before 2:30 a.m. (CDT) on August 6.

Atmospheric radiation measurement unmanned aerospace vehicle (ARM-UAV) program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolton, W.R.

1996-11-01

ARM-UAV is part of the multi-agency U.S. Global Change Research Program and is addressing the largest source of uncertainty in predicting climatic response: the interaction of clouds and the sun`s energy in the Earth`s atmosphere. An important aspect of the program is the use of unmanned aerospace vehicles (UAVs) as the primary airborne platform. The ARM-UAV Program has completed two major flight series: The first series conducted in April, 1994, using an existing UAV (the General Atomics Gnat 750) consisted of eight highly successful flights at the DOE climate site in Oklahoma. The second series conducted in September/October, 1995, usingmore » two piloted aircraft (Egrett and Twin Otter), featured simultaneous measurements above and below clouds and in clear sky. Additional flight series are planned to continue study of the cloudy and clear sky energy budget in the Spring and Fall of 1996 over the DOE climate site in Oklahoma. 3 refs., 4 figs., 1 tab.« less

Visual Attention Allocation Between Robotic Arm and Environmental Process Control: Validating the STOM Task Switching Model

NASA Technical Reports Server (NTRS)

Wickens, Christopher; Vieanne, Alex; Clegg, Benjamin; Sebok, Angelia; Janes, Jessica

2015-01-01

Fifty six participants time shared a spacecraft environmental control system task with a realistic space robotic arm control task in either a manual or highly automated version. The former could suffer minor failures, whose diagnosis and repair were supported by a decision aid. At the end of the experiment this decision aid unexpectedly failed. We measured visual attention allocation and switching between the two tasks, in each of the eight conditions formed by manual-automated arm X expected-unexpected failure X monitoring- failure management. We also used our multi-attribute task switching model, based on task attributes of priority interest, difficulty and salience that were self-rated by participants, to predict allocation. An un-weighted model based on attributes of difficulty, interest and salience accounted for 96 percent of the task allocation variance across the 8 different conditions. Task difficulty served as an attractor, with more difficult tasks increasing the tendency to stay on task.

Members of the STS-100 crew look over hardware in SSPF during CEIT

NASA Technical Reports Server (NTRS)

2000-01-01

STS-100 Commander Kent Rominger and Mission Specialist Umberto Guidoni (right), with the European Space Agency, pose for a photo during Crew Equipment Interface Test activities in the Space Station Processing Facility. Behind them is the Space Station Remote Manipulator System (SSRMS), also known as the Canadian arm, which is part of the payload on their mission. The SSRMS is the primary means of transferring payloads between the orbiter payload bay and the International Space Station for assembly. The 56-foot-long robotic arm includes two 12-foot booms joined by a hinge. Seven joints on the arm allow highly flexible and precise movement. The payload also includes the Multi-Purpose Logistics Module (MPLM) Raffaello. MPLMs are pressurized modules that will serve as the International Space Station's '''moving vans,''' carrying laboratory racks filled with equipment, experiments and supplies to and from the station aboard the Space Shuttle. Mission STS-100 is scheduled to launch April 19, 2001.

KSC-2010-1194

NASA Image and Video Library

2010-01-12

CAPE CANAVERAL, Fla. - In the Remote Manipulator System Lab inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' orbiter boom sensor system, or OBSS, is prepared for maintenance. The 50-foot-long OBSS attaches to the end of the shuttle’s robotic arm and supports the cameras and laser systems used to inspect the shuttle’s thermal protection system while in space. Atlantis is next slated to deliver an Integrated Cargo Carrier and Russian-built Mini Research Module to the International Space Station on the STS-132 mission. The second in a series of new pressurized components for Russia, the module will be permanently attached to the Zarya module. Three spacewalks are planned to store spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-purpose Laboratory Module also are payloads on the flight. Launch is targeted for May 14, 2010. Photo credit: NASA/Jack Pfaller

International Space Station (ISS)

NASA Image and Video Library

2002-06-07

Pictured here is the forward docking port on the International Space Station's (ISS) Destiny Laboratory as seen by one of the STS-111 crewmembers from the Space Shuttle Orbiter Endeavour just prior to docking. In June 2002, STS-111 provided the Space Station with a new crew, Expedition Five, replacing Expedition Four after remaining a record-setting 196 days in space. Three spacewalks enabled the STS-111 crew to accomplish additional mission objectives: the delivery and installation of a new platform for the ISS robotic arm, the Mobile Base System (MBS) which is an important part of the Station's Mobile Servicing System allowing the robotic arm to travel the length of the Station; the replacement of a wrist roll joint on the Station's robotic arm; and unloading supplies and science experiments form the Leonardo Multi-Purpose Logistics Module, which made its third trip to the orbital outpost. The STS-111 mission, the 14th Shuttle mission to visit the ISS, was launched on June 5, 2002 and landed June 19, 2002.

Shoulder-arm morbidity in patients with sentinel node biopsy and complete axillary dissection--data from a prospective randomised trial.

PubMed

Helms, G; Kühn, T; Moser, L; Remmel, E; Kreienberg, R

2009-07-01

Axillary lymph node dissection (ALND) as part of surgical treatment in breast cancer has been the standard procedure for many decades. However, patients frequently develop shoulder-arm morbidity postoperatively. Recently, sentinel node (SN) biopsy has been established as a new standard of care for axillary staging in breast cancer. This study compares postoperative morbidity between ALND and SN biopsy. The results are compared with the existing literature. Between November 2000 and September 2002, 181 women with early stage breast cancer underwent primary surgery following preoperative randomisation into two groups, a "standard group" (SN biopsy was followed by ALND) and a study group (surgical procedure consisting of only SN biopsy when histologically metastasis-free SN was present). Follow-up data (362 sessions; 6 months to 3 years after primary surgery) were available from 150 patients. A summary morbidity score was calculated from four subjective (arm-strength, arm-mobility, arm swelling, pain) and four objective (arm-strength, arm-mobility, lymphedema, sensitivity) criteria. Fifty seven patients underwent SN biopsy only. Ninety three patients underwent ALND, 57 of which had lymph nodes free of metastasis and 36 had lymph nodes with metastasis and axillary clearing. Shoulder-arm morbidity was significantly different between the groups. Patients treated with SN biopsy only scored better on subjective and objective criteria. Postsurgical shoulder-arm morbidity is a major long-term problem in patients undergoing surgical treatment for breast cancer. This prospective study showed significantly less severe shoulder-arm morbidity following SN biopsy compared to patients undergoing ALND.

The physiotherapeutic context of loss of dominant arm function due to occupational accidents.

PubMed

Kostiukow, Anna; Kaluga, Elżbieta; Samborski, Włodzimierz; Rostkowska, Elżbieta

2016-12-23

The study examines the problem of dominant arm function loss in rural adult patients due to work-related accidents. The types of risks involved in farmyard work include falling from a height, manually moving loads, overturning/accident whilst driving an agricultural tractor, noise and vibration, use of pesticides, and the risk of being cut or injured. The study focuses on adaptation of the non-dominant arm. The main aim of the study was evaluation of visual-motor coordination on the basis of performance of the non-dominant hand in patients after the loss of function of the dominant arm. The research sample consisted of 52 patients with a permanent or temporary loss of function or severely limited function of the dominant arm. The subjects were patients with arm amputations due to various occupational injuries sustained while operating agricultural and construction machinery and forestry equipment, following traumas or complicated medical surgeries of the arm, or due to car accidents. The following tests were applied in the analysis: I) Dufour cross-shaped apparatus test for assessing visual motor-coordination; II) paper-and-pencil tests and the Relay Baton motor fitness test; III) anthropometric measurements; IV) Edinburgh Handedness Inventory; and V) a questionnaire survey. The results of the apparatus and motor tests indicate the same tendency: reaction to stimuli measured on the basis of performance of the non-dominant arm is longer in shorter and older patients. Visual-motor coordination, as measured by the performance of the non-dominant arm, is significantly affected by the subject's body height and arm length.

Employment of the El Salvador Armed Forces for Internal Security

DTIC Science & Technology

2011-02-02

and in which the familiar life develops undressed of the fear; a country where a climate exists that favors the investment and the opportunities of...armed forces the experience and familiarize them with the roots of the problems, causes, and conditions that generate the violence in the country...police, military and fiscal members, and members of other institutions involved in the combating of crime have to be familiar with the legal procedures

The Nuclear Power and Nuclear Weapons Connection.

ERIC Educational Resources Information Center

Leventhal, Paul

1990-01-01

Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

Problems Relating to Examinations in Three-Year Technical/Natural Science Courses of Study at the Federal Armed Forces University, Munich.

ERIC Educational Resources Information Center

Ulbricht, Kurt; Zimmermann, Peter

1981-01-01

Problems encountered in testing in aerospace engineering courses in an accelerated technical program of a German military university are outlined. Four common grading procedures are compared, and the optimum length of written tests is discussed. (MSE)

A Course in Natural Science and National Security in the Nuclear Age.

ERIC Educational Resources Information Center

Blumberg, Avrom A.

1983-01-01

Topics and instructional strategies for an upper-level, problem-oriented science and society course at De Paul University are described. Objectives and grading procedures for "Problems in Modern Warfare, Arms Control, and Disarmament" are also described. Course syllabus, bibliography, and sample quizzes/examinations are available from…

Metformin and/or clomiphene do not adversely affect liver or renal function in women with polycystic ovary syndrome.

PubMed

Aubuchon, Mira; Kunselman, Allen R; Schlaff, William D; Diamond, Michael P; Coutifaris, Christos; Carson, Sandra A; Steinkampf, Michael P; Carr, Bruce R; McGovern, Peter G; Cataldo, Nicholas A; Gosman, Gabriella G; Nestler, John E; Myers, Evan R; Legro, Richard S

2011-10-01

Nonalcoholic fatty liver disease is common to insulin-resistant states such as polycystic ovary syndrome (PCOS). Metformin (MET) is often used to treat PCOS but information is limited as to its effects on liver function. We sought to determine the effects of MET on serum hepatic parameters in PCOS patients. This was a secondary analysis of a randomized, doubled-blind trial from 2002-2004. This multi-center clinical trial was conducted in academic centers. Six hundred twenty-six infertile women with PCOS with serum liver function parameters less than twice the upper limit of normal were included. Clomiphene citrate (n = 209), MET (n = 208), or combined (n = 209) were given for up to 6 months. The percent change from baseline in renal and liver function between- and within-treatment arms was assessed. Renal function improved in all treatment arms with significant decreases in serum blood urea nitrogen levels (range, -14.7 to -21.3%) as well as creatinine (-4.2 to -6.9%). There were similar decreases in liver transaminase levels in the clomiphene citrate and combined arms (-10% in bilirubin, -9 to -11% in transaminases) without significant changes in the MET arm. When categorizing baseline bilirubin, aspartate aminotransferase, and alanine aminotransferase into tertiles, there were significant within-treatment arm differences between the tertiles with the highest tertile having the largest decrease from baseline regardless of treatment arm. Women with PCOS can safely use metformin and clomiphene even in the setting of mildly abnormal liver function parameters, and both result in improved renal function.

A Monte-Carlo game theoretic approach for Multi-Criteria Decision Making under uncertainty

NASA Astrophysics Data System (ADS)

Madani, Kaveh; Lund, Jay R.

2011-05-01

Game theory provides a useful framework for studying Multi-Criteria Decision Making problems. This paper suggests modeling Multi-Criteria Decision Making problems as strategic games and solving them using non-cooperative game theory concepts. The suggested method can be used to prescribe non-dominated solutions and also can be used as a method to predict the outcome of a decision making problem. Non-cooperative stability definitions for solving the games allow consideration of non-cooperative behaviors, often neglected by other methods which assume perfect cooperation among decision makers. To deal with the uncertainty in input variables a Monte-Carlo Game Theory (MCGT) approach is suggested which maps the stochastic problem into many deterministic strategic games. The games are solved using non-cooperative stability definitions and the results include possible effects of uncertainty in input variables on outcomes. The method can handle multi-criteria multi-decision-maker problems with uncertainty. The suggested method does not require criteria weighting, developing a compound decision objective, and accurate quantitative (cardinal) information as it simplifies the decision analysis by solving problems based on qualitative (ordinal) information, reducing the computational burden substantially. The MCGT method is applied to analyze California's Sacramento-San Joaquin Delta problem. The suggested method provides insights, identifies non-dominated alternatives, and predicts likely decision outcomes.

Problems With Deployment of Multi-Domained, Multi-Homed Mobile Networks

NASA Technical Reports Server (NTRS)

Ivancic, William D.

2008-01-01

This document describes numerous problems associated with deployment of multi-homed mobile platforms consisting of multiple networks and traversing large geographical areas. The purpose of this document is to provide insight to real-world deployment issues and provide information to groups that are addressing many issues related to multi-homing, policy-base routing, route optimization and mobile security - particularly those groups within the Internet Engineering Task Force.

A brittle star-like robot capable of immediately adapting to unexpected physical damage.

PubMed

Kano, Takeshi; Sato, Eiki; Ono, Tatsuya; Aonuma, Hitoshi; Matsuzaka, Yoshiya; Ishiguro, Akio

2017-12-01

A major challenge in robotic design is enabling robots to immediately adapt to unexpected physical damage. However, conventional robots require considerable time (more than several tens of seconds) for adaptation because the process entails high computational costs. To overcome this problem, we focus on a brittle star-a primitive creature with expendable body parts. Brittle stars, most of which have five flexible arms, occasionally lose some of them and promptly coordinate the remaining arms to escape from predators. We adopted a synthetic approach to elucidate the essential mechanism underlying this resilient locomotion. Specifically, based on behavioural experiments involving brittle stars whose arms were amputated in various ways, we inferred the decentralized control mechanism that self-coordinates the arm motions by constructing a simple mathematical model. We implemented this mechanism in a brittle star-like robot and demonstrated that it adapts to unexpected physical damage within a few seconds by automatically coordinating its undamaged arms similar to brittle stars. Through the above-mentioned process, we found that physical interaction between arms plays an essential role for the resilient inter-arm coordination of brittle stars. This finding will help develop resilient robots that can work in inhospitable environments. Further, it provides insights into the essential mechanism of resilient coordinated motions characteristic of animal locomotion.

A brittle star-like robot capable of immediately adapting to unexpected physical damage

PubMed Central

Sato, Eiki; Ono, Tatsuya; Aonuma, Hitoshi; Matsuzaka, Yoshiya; Ishiguro, Akio

2017-01-01

A major challenge in robotic design is enabling robots to immediately adapt to unexpected physical damage. However, conventional robots require considerable time (more than several tens of seconds) for adaptation because the process entails high computational costs. To overcome this problem, we focus on a brittle star—a primitive creature with expendable body parts. Brittle stars, most of which have five flexible arms, occasionally lose some of them and promptly coordinate the remaining arms to escape from predators. We adopted a synthetic approach to elucidate the essential mechanism underlying this resilient locomotion. Specifically, based on behavioural experiments involving brittle stars whose arms were amputated in various ways, we inferred the decentralized control mechanism that self-coordinates the arm motions by constructing a simple mathematical model. We implemented this mechanism in a brittle star-like robot and demonstrated that it adapts to unexpected physical damage within a few seconds by automatically coordinating its undamaged arms similar to brittle stars. Through the above-mentioned process, we found that physical interaction between arms plays an essential role for the resilient inter-arm coordination of brittle stars. This finding will help develop resilient robots that can work in inhospitable environments. Further, it provides insights into the essential mechanism of resilient coordinated motions characteristic of animal locomotion. PMID:29308250

A quasi-spectral method for Cauchy problem of 2/D Laplace equation on an annulus

NASA Astrophysics Data System (ADS)

Saito, Katsuyoshi; Nakada, Manabu; Iijima, Kentaro; Onishi, Kazuei

2005-01-01

Real numbers are usually represented in the computer as a finite number of digits hexa-decimal floating point numbers. Accordingly the numerical analysis is often suffered from rounding errors. The rounding errors particularly deteriorate the precision of numerical solution in inverse and ill-posed problems. We attempt to use a multi-precision arithmetic for reducing the rounding error evil. The use of the multi-precision arithmetic system is by the courtesy of Dr Fujiwara of Kyoto University. In this paper we try to show effectiveness of the multi-precision arithmetic by taking two typical examples; the Cauchy problem of the Laplace equation in two dimensions and the shape identification problem by inverse scattering in three dimensions. It is concluded from a few numerical examples that the multi-precision arithmetic works well on the resolution of those numerical solutions, as it is combined with the high order finite difference method for the Cauchy problem and with the eigenfunction expansion method for the inverse scattering problem.

Task decomposition for a multilimbed robot to work in reachable but unorientable space

NASA Technical Reports Server (NTRS)

Su, Chau; Zheng, Yuan F.

1991-01-01

Robot manipulators installed on legged mobile platforms are suggested for enlarging robot workspace. To plan the motion of such a system, the arm-platform motion coordination problem is raised, and a task decomposition is proposed to solve the problem. A given task described by the destination position and orientation of the end effector is decomposed into subtasks for arm manipulation and for platform configuration, respectively. The former is defined as the end-effector position and orientation with respect to the platform, and the latter as the platform position and orientation in the base coordinates. Three approaches are proposed for the task decomposition. The approaches are also evaluated in terms of the displacements, from which an optimal approach can be selected.

Arms races between and within species.

PubMed

Dawkins, R; Krebs, J R

1979-09-21

An adaptation in one lineage (e.g. predators) may change the selection pressure on another lineage (e.g. prey), giving rise to a counter-adaptation. If this occurs reciprocally, an unstable runaway escalation or 'arms race' may result. We discuss various factors which might give one side an advantage in an arms race. For example, a lineage under strong selection may out-evolve a weakly selected one (' the life-dinner principle'). We then classify arms races in two independent ways. They may be symmetric or asymmetric, and they may be interspecific or intraspecific. Our example of an asymmetric interspecific arms race is that between brood parasites and their hosts. The arms race concept may help to reduce the mystery of why cuckoo hosts are so good at detecting cuckoo eggs, but so bad at detecting cuckoo nestlings. The evolutionary contest between queen and worker ants over relative parental investment is a good example of an intraspecific asymmetric arms race. Such cases raise special problems because the participants share the same gene pool. Interspecific symmetric arms races are unlikely to be important, because competitors tend to diverge rather than escalate competitive adaptations. Intraspecific symmetric arms races, exemplified by adaptations for male-male competition, may underlie Cope's Rule and even the extinction of lineages. Finally we consider ways in which arms races can end. One lineage may drive the other to extinction; one may reach an optimum, thereby preventing the other from doing so; a particularly interesting possibility, exemplified by flower-bee coevolution, is that both sides may reach a mutual local optimum; lastly, arms races may have no stable and but may cycle continuously. We do not wish necessarily to suggest that all, or even most, evolutionary change results from arms races, but we do suggest that the arms race concept may help to resolve three long-standing questions in evolutionary theory.

Synergistic observations of convective cloud life-cycle during the Mid-latitude Continental Convective Clouds Experiment (MC3E)

NASA Astrophysics Data System (ADS)

Jensen, M. P.; Petersen, W. A.; Giangrande, S.; Heymsfield, G. M.; Kollias, P.; Rutledge, S. A.; Schwaller, M.; Zipser, E. J.

2011-12-01

The Midlatitude Continental Convective Clouds Experiment (MC3E) took place from 22 April through 6 June 2011 centered at the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Southern Great Plains Central Facility in north-central Oklahoma. This campaign was a joint effort between the ARM and the National Aeronautics and Space Administration's (NASA) Global Precipitation Measurement mission Ground Validation program. It was the first major field campaign to take advantage of numerous new radars and other remote sensing instrumentation purchased through the American Recovery and Reinvestment Act of 2009. The measurement strategy for this field campaign was to provide a well-defined forcing dataset for modeling efforts coupled with detailed observations of cloud/precipitation dynamics and microphysics within the domain highlighted by advanced multi-scale, multi-frequency radar remote sensing. These observations are aimed at providing important insights into eight different components of convective simulation and microphysical parameterization: (1) pre-convective environment, (2) convective initiation, (3) updraft/downdraft dynamics, (4) condensate transport/detrainment/entrainment, (5) precipitation and cloud microphysics, (6) influence on the environment, (7) influence on radiation, and (8) large-scale forcing. In order to obtain the necessary dataset, the MC3E surface-based observational network included six radiosonde launch sites each launching 4-8 sondes per day, three X-band scanning ARM precipitation radars, a C-band scanning ARM precipitation radar, the NASA N-Pol (S-band) scanning radar, the NASA D3R Ka/Ku-band radar, the Ka/W-band scanning ARM cloud radar, vertically pointing radar systems at Ka-, S- and UHF band, a network of over 20 disdrometers and rain gauges and the full complement of radiation, cloud and atmospheric state observations available at the ARM facility. This surface-based network was complemented by aircraft measurements by the NASA ER-2 high altitude aircraft which included a radar system (Ka/Ku band) and multiple passive microwave radiometers (10-183 GHz) and the University of North Dakota Citation which included a full suite of in situ microphysics instruments. The campaign was successful in providing observations over a wide variety of convective cloud types, from shallow non-precipitating cloud fields to shallow-to-deep transitions to mature deep convective systems some of which included severe weather. We will present an overview of the convective cloud conditions that were observed, the status MC3E datastreams and a summary of some of the preliminary results.

Enhancing the sensitivity of slow light MZI biosensors through multi-hole defects

NASA Astrophysics Data System (ADS)

Qin, Kun; Zhao, Yiliang; Hu, Shuren; Weiss, Sharon M.

2018-02-01

We demonstrate enhanced detection sensitivity of a slow light Mach-Zehnder interferometer (MZI) sensor by incorporating multi-hole defects (MHDs). Slow light MZI biosensors with a one-dimensional photonic crystal in one arm have been previously shown to improve the performance of traditional MZI sensors based on the increased lightmatter interaction that takes place in the photonic crystal region of the structure. Introducing MHDs in the photonic crystal region increases the available surface area for molecular attachment and further increases the enhanced lightmatter interaction capability of slow light MZIs. The MHDs allow analyte to interact with a greater fraction of the guided wave in the MZI. For a slow light MHD MZI sensor with a 16 μm long sensing arm, a bulk sensitivity of 151,000 rad/RIU-cm is demonstrated experimentally, which is approximately two-fold higher than our previously reported slow light MZI sensors and thirteen-fold higher than traditional MZI biosensors with millimeter length sensing regions. For the label-free detection of nucleic acids, the slow light MZI with MHDs also exhibits a two-fold sensitivity improvement in experiment compared to the slow light MZI without MHDs. Because the detection sensitivity of slow light MHD MZIs scales with the length of the sensing arm, the tradeoff between detection limit and device size can be appropriately mitigated for different applications. All experimental results presented in this work are in good agreement with finite difference-time domain-calculations. Overall, the slow light MZI biosensors with MHDs are a promising platform for highly sensitive and multiplexed lab-on-chip systems.

Control of multi-joint arm movements for the manipulation of touch in keystroke by expert pianists

PubMed Central

2010-01-01

Background Production of a variety of finger-key touches in the piano is essential for expressive musical performance. However, it remains unknown how expert pianists control multi-joint finger and arm movements for manipulating the touch. The present study investigated differences in kinematics and kinetics of the upper-limb movements while expert pianists were depressing a key with two different touches: pressed and struck. The former starts key-depression with the finger-tip contacting the key, whereas the latter involves preparatory arm-lift before striking the key. To determine the effect of individual muscular torque (MUS) as well as non-muscular torques on joint acceleration, we performed a series of inverse and forward dynamics computations. Results The pressed touch showed smaller elbow extension velocity, and larger shoulder and finger flexion velocities during key-depression compared with the struck touch. The former touch also showed smaller elbow extension acceleration directly attributed to the shoulder MUS. In contrast, the shoulder flexion acceleration induced by elbow and wrist MUS was greater for the pressed touch than the struck touch. Towards the goal of producing the target finger-key contact dynamics, the pressed and struck touches effectively took advantage of the distal-to-proximal and proximal-to-distal inter-segmental dynamics, respectively. Furthermore, a psychoacoustic experiment confirmed that a tone elicited by the pressed touch was perceived softer than that by the struck touch. Conclusion The present findings suggest that manipulation of tone timbre depends on control of inter-segmental dynamics in piano keystroke. PMID:20630085

Optomechanical design concept for GMACS: a wide-field multi-object moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT)

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Prochaska, Travis; Shectman, Stephen A.; Hammond, Randolph P.; Barkhouser, Robert H.; DePoy, D. L.; Marshall, J. L.

2012-09-01

We describe the conceptual optomechanical design for GMACS, a wide-field, multi-object, moderate-resolution optical spectrograph for the Giant Magellan Telescope (GMT). GMACS is a candidate first-light instrument for the GMT and will be one of several instruments housed in the Gregorian Instrument Rotator (GIR) located at the Gregorian focus. The instrument samples a 9 arcminute x 18 arcminute field of view providing two resolution modes (i.e, low resolution, R ~ 2000, and moderate resolution, R ~ 4000) over a 3700 Å to 10200 Å wavelength range. To minimize the size of the optics, four fold mirrors at the GMT focal plane redirect the full field into four individual "arms", that each comprises a double spectrograph with a red and blue channel. Hence, each arm samples a 4.5 arcminute x 9 arcminute field of view. The optical layout naturally leads to three separate optomechanical assemblies: a focal plane assembly, and two identical optics modules. The focal plane assembly contains the last element of the telescope's wide-field corrector, slit-mask, tent-mirror assembly, and slit-mask magazine. Each of the two optics modules supports two of the four instrument arms and houses the aft-optics (i.e. collimators, dichroics, gratings, and cameras). A grating exchange mechanism, and articulated gratings and cameras facilitate multiple resolution modes. In this paper we describe the details of the GMACS optomechanical design, including the requirements and considerations leading to the design, mechanism details, optics mounts, and predicted flexure performance.

BOMBOLO: a Multi-Band, Wide-field, Near UV/Optical Imager for the SOAR 4m Telescope

NASA Astrophysics Data System (ADS)

Angeloni, R.; Guzmán, D.; Puzia, T. H.; Infante, L.

2014-10-01

BOMBOLO is a new multi-passband visitor instrument for SOAR observatory. The first fully Chilean instrument of its kind, it is a three-arms imager covering the near-UV and optical wavelengths. The three arms work simultaneously and independently, providing synchronized imaging capability for rapid astronomical events. BOMBOLO will be able to address largely unexplored events in the minute-to-second timescales, with the following leading science cases: 1) Simultaneous Multiband Flickering Studies of Accretion Phenomena; 2) Near UV/Optical Diagnostics of Stellar Evolutionary Phases; 3) Exoplanetary Transits and 4) Microlensing Follow-Up. BOMBOLO optical design consists of a wide field collimator feeding two dychroics at 390 and 550 nm. Each arm encompasses a camera, filter wheel and a science CCD230-42, imaging a 7 x 7 arcmin field of view onto a 2k x 2k image. The three CCDs will have different coatings to optimise the efficiencies of each camera. The detector controller to run the three cameras will be Torrent (the NOAO open-source system) and a PanView application will run the instrument and produce the data-cubes. The instrument is at Conceptual Design stage, having been approved by the SOAR Board of Directors as a visitor instrument in 2012 and having been granted full funding from CONICYT, the Chilean State Agency of Research, in 2013. The Design Phase is starting now and will be completed in late 2014, followed by a construction phase in 2015 and 2016A, with expected Commissioning in 2016B and 2017A.

The Dynamic Multi-objective Multi-vehicle Covering Tour Problem

DTIC Science & Technology

2013-06-01

AI Artificial Intelligence AUV Autonomous Underwater Vehicle CLP Clover Leaf Problem CSP Covering Salesman Problem CTP Covering Tour Problem CVRP...introduces a new formalization - the DMOMCTP. Related works from routing problems, Artificial Intelligence ( AI ), and MOPs are discussed briefly. As a...the rest of that framework being replaced. The codebase differs from jMetal 4.2 in that it can handle the time and DM dependent nature of the DMOMCTP

Data fusion of multiple kinect sensors for a rehabilitation system.

PubMed

Huibin Du; Yiwen Zhao; Jianda Han; Zheng Wang; Guoli Song

2016-08-01

Kinect-like depth sensors have been widely used in rehabilitation systems. However, single depth sensor processes limb-blocking, data loss or data error poorly, making it less reliable. This paper focus on using two Kinect sensors and data fusion method to solve these problems. First, two Kinect sensors capture the motion data of the healthy arm of the hemiplegic patient; Second, merge the data using the method of Set-Membership-Filter (SMF); Then, mirror this motion data by the Middle-Plane; In the end, control the wearable robotic arm driving the patient's paralytic arm so that the patient can interactively and initiatively complete a variety of recovery actions prompted by computer with 3D animation games.

Computer coordination of limb motion for locomotion of a multiple-armed robot for space assembly

NASA Technical Reports Server (NTRS)

Klein, C. A.; Patterson, M. R.

1982-01-01

Consideration is given to a possible robotic system for the construction of large space structures, which may be described as a multiple general purpose arm manipulator vehicle that can walk over the structure under construction to a given site for further work. A description is presented of the locomotion of such a vehicle, modeling its arms in terms of a currently available industrial manipulator. It is noted that for whatever maximum speed of operation is chosen, rapid changes in robot velocity create situations in which already-selected handholds are no longer practical. A step is added to the 'free gait' walking algorithm in order to solve this problem.

STS-100 MPLM Raffaello is moved to the payload canister

NASA Technical Reports Server (NTRS)

2001-01-01

KENNEDY SPACE CENTER, Fla. - The Multi-Purpose Logistics Module Raffaello is lowered into the payload canister alongside the Canadian robotic arm, SSRMS, already in place. Both elements are part of the payload on mission STS-100 to the International Space Station. Raffaello carries six system racks and two storage racks for the U.S. Lab. The arm has seven motorized joints and is capable of handling large payloads and assisting with docking the Space Shuttle. The SSRMS is self-relocatable with a Latching End Effector so it can be attached to complementary ports spread throughout the Station'''s exterior surfaces. Launch of STS-100 is scheduled for April 19, 2001 at 2:41 p.m. EDT from Launch Pad 39A.

STS-100 MPLM Raffaello is moved to the payload canister

NASA Technical Reports Server (NTRS)

2001-01-01

KENNEDY SPACE CENTER, Fla. - Viewed from the end, the Multi- Purpose Logistics Module Raffaello is lowered into the payload canister behind the Canadian robotic arm, SSRMS, already in place. Both elements are part of the payload on mission STS-100 to the International Space Station. Raffaello carries six system racks and two storage racks for the U.S. Lab. The arm has seven motorized joints and is capable of handling large payloads and assisting with docking the Space Shuttle. The SSRMS is self- relocatable with a Latching End Effector so it can be attached to complementary ports spread throughout the Station'''s exterior surfaces. Launch of STS-100 is scheduled for April 19, 2001 at 2:41 p.m. EDT from Launch Pad 39A.

View of the Columbia's RMS arm and end effector grasping IECM

NASA Image and Video Library

1982-06-27

STS004-37-670 (27 June-4 July 1982) --- The North Atlantic Ocean southeast of the Bahamas serves as backdrop for this 70mm scene of the Columbia?s remote manipulator system (RMS) arm and hand-like device (called and end effector) grasping a multi-instrument monitor for detecting contaminants. The experiments is called the induced environment contaminant monitor (IECM). The small box contains 11 instruments for checking the contaminants in and around the orbiter?s cargo bay which might adversely affect delicate experiments carried onboard. Astronauts Thomas K. Mattingly II and Henry W. Hartsfield Jr. manned the Columbia for seven days and one hour. The Columbia?s vertical tail and orbital maneuvering system (OMS) pods are at left foreground. Photo credit: NASA

The study on hand-arm vibration syndrome in China.

PubMed

Lin, Wang; Chunzhi, Zhang; Qiang, Zhang; Kai, Zhang; Xiaoli, Zeng

2005-07-01

To review the main achievement and problems of study on hand-arm vibration syndrome in China. The epidemiological and clinical study indicate that HAVS was reported from almost provinces in China, the prevalence of VWF ranges from 2.5% to 82.8% in the workers with vibrating tool use. The exposure-response relationship between prevalence of VWF and intensity and duration of exposed to hand-transmitted vibration has confirmed. Diagnostic criteria of HAVS has been established and performed by Chinese government in 1985, and it was revised by government as a national standard for occupational health in 2002. The "hygienic standard for hand-transmitted vibration in workplace" as a national standard and the "methods of measurement and assessment for hand-transmitted vibration" as a recommend standard were published by government also. The limited value of exposed to hand-arm vibration was 5.0 m/s2 that is energy equivalent frequency-weighted acceleration for a period of 4 h (ahw(4)). There are some problems in this field of China need to further study in the future.

An octopus-bioinspired solution to movement and manipulation for soft robots.

PubMed

Calisti, M; Giorelli, M; Levy, G; Mazzolai, B; Hochner, B; Laschi, C; Dario, P

2011-09-01

Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

The effects of adding single-joint exercises to a multi-joint exercise resistance training program on upper body muscle strength and size in trained men.

PubMed

de França, Henrique Silvestre; Branco, Paulo Alexandre Nordeste; Guedes Junior, Dilmar Pinto; Gentil, Paulo; Steele, James; Teixeira, Cauê Vazquez La Scala

2015-08-01

The aim of this study was compare changes in upper body muscle strength and size in trained men performing resistance training (RT) programs involving multi-joint plus single-joint (MJ+SJ) or only multi-joint (MJ) exercises. Twenty young men with at least 2 years of experience in RT were randomized in 2 groups: MJ+SJ (n = 10; age, 27.7 ± 6.6 years) and MJ (n = 10; age, 29.4 ± 4.6 years). Both groups trained for 8 weeks following a linear periodization model. Measures of elbow flexors and extensors 1-repetition maximum (1RM), flexed arm circumference (FAC), and arm muscle circumference (AMC) were taken pre- and post-training period. Both groups significantly increased 1RM for elbow flexion (4.99% and 6.42% for MJ and MJ+SJ, respectively), extension (10.60% vs 9.79%, for MJ and MJ+SJ, respectively), FAC (1.72% vs 1.45%, for MJ and MJ+SJ, respectively), and AMC (1.33% vs 3.17% for MJ and MJ+SJ, respectively). Comparison between groups revealed no significant difference in any variable. In conclusion, 8 weeks of RT involving MJ or MJ+SJ resulted in similar alterations in muscle strength and size in trained participants. Therefore, the addition of SJ exercises to a RT program involving MJ exercises does not seem to promote additional benefits to trained men, suggesting MJ-only RT to be a time-efficient approach.

Integrated Modeling of Spacecraft Touch-and-Go Sampling

NASA Technical Reports Server (NTRS)

Quadrelli, Marco

2009-01-01

An integrated modeling tool has been developed to include multi-body dynamics, orbital dynamics, and touch-and-go dynamics for spacecraft covering three types of end-effectors: a sticky pad, a brush-wheel sampler, and a pellet gun. Several multi-body models of a free-flying spacecraft with a multi-link manipulator driving these end-effectors have been tested with typical contact conditions arising when the manipulator arm is to sample the surface of an asteroidal body. The test data have been infused directly into the dynamics formulation including such information as the mass collected as a function of end-effector longitudinal speed for the brush-wheel and sticky-pad samplers, and the mass collected as a function of projectile speed for the pellet gun sampler. These data represent the realistic behavior of the end effector while in contact with a surface, and represent a low-order model of more complex contact conditions that otherwise would have to be simulated. Numerical results demonstrate the adequacy of these multibody models for spacecraft and manipulator- arm control design. The work contributes to the development of a touch-and-go testbed for small body exploration, denoted as the GREX Testbed (GN&C for Rendezvous-based EXploration). The GREX testbed addresses the key issues involved in landing on an asteroidal body or comet; namely, a complex, low-gravity field; partially known terrain properties; possible comet outgassing; dust ejection; and navigating to a safe and scientifically desirable zone.

Mineral spirits poisoning

MedlinePlus

... Rapid heartbeat NERVOUS SYSTEM Burning sensations Convulsions Dizziness Loss of alertness Memory problems Nervousness Numbness in arms and legs SKIN Burns Irritation Necrosis (holes) in the skin or underlying tissues

Neural dynamic programming and its application to control systems

NASA Astrophysics Data System (ADS)

Seong, Chang-Yun

There are few general practical feedback control methods for nonlinear MIMO (multi-input-multi-output) systems, although such methods exist for their linear counterparts. Neural Dynamic Programming (NDP) is proposed as a practical design method of optimal feedback controllers for nonlinear MIMO systems. NDP is an offspring of both neural networks and optimal control theory. In optimal control theory, the optimal solution to any nonlinear MIMO control problem may be obtained from the Hamilton-Jacobi-Bellman equation (HJB) or the Euler-Lagrange equations (EL). The two sets of equations provide the same solution in different forms: EL leads to a sequence of optimal control vectors, called Feedforward Optimal Control (FOC); HJB yields a nonlinear optimal feedback controller, called Dynamic Programming (DP). DP produces an optimal solution that can reject disturbances and uncertainties as a result of feedback. Unfortunately, computation and storage requirements associated with DP solutions can be problematic, especially for high-order nonlinear systems. This dissertation presents an approximate technique for solving the DP problem based on neural network techniques that provides many of the performance benefits (e.g., optimality and feedback) of DP and benefits from the numerical properties of neural networks. We formulate neural networks to approximate optimal feedback solutions whose existence DP justifies. We show the conditions under which NDP closely approximates the optimal solution. Finally, we introduce the learning operator characterizing the learning process of the neural network in searching the optimal solution. The analysis of the learning operator provides not only a fundamental understanding of the learning process in neural networks but also useful guidelines for selecting the number of weights of the neural network. As a result, NDP finds---with a reasonable amount of computation and storage---the optimal feedback solutions to nonlinear MIMO control problems that would be very difficult to solve with DP. NDP was demonstrated on several applications such as the lateral autopilot logic for a Boeing 747, the minimum fuel control of a double-integrator plant with bounded control, the backward steering of a two-trailer truck, and the set-point control of a two-link robot arm.

The technical consideration of multi-beam mask writer for production

NASA Astrophysics Data System (ADS)

Lee, Sang Hee; Ahn, Byung-Sup; Choi, Jin; Shin, In Kyun; Tamamushi, Shuichi; Jeon, Chan-Uk

2016-10-01

Multi-beam mask writer is under development to solve the throughput and patterning resolution problems in VSB mask writer. Theoretically, the writing time is appropriate for future design node and the resolution is improved with multi-beam mask writer. Many previous studies show the feasible results of resolution, CD control and registration. Although such technical results of development tool seem to be enough for mass production, there are still many unexpected problems for real mass production. In this report, the technical challenges of multi-beam mask writer are discussed in terms of production and application. The problems and issues are defined based on the performance of current development tool compared with the requirements of mask quality. Using the simulation and experiment, we analyze the specific characteristics of electron beam in multi-beam mask writer scheme. Consequently, we suggest necessary specifications for mass production with multi-beam mask writer in the future.

The role of propriospinal neuronal network in transmitting the alternating muscular activities of flexor and extensor in parkinsonian tremor.

PubMed

Hao, M; He, X; Lan, N

2012-01-01

It has been shown that normal cyclic movement of human arm and resting limb tremor in Parkinson's disease (PD) are associated with the oscillatory neuronal activities in different cerebral networks, which are transmitted to the antagonistic muscles via the same spinal pathway. There are mono-synaptic and multi-synaptic corticospinal pathways for conveying motor commands. This study investigates the plausible role of propriospinal neuronal (PN) network in the C3-C4 levels in multi-synaptic transmission of cortical commands for oscillatory movements. A PN network model is constructed based on known neurophysiological connections, and is hypothesized to achieve the conversion of cortical oscillations into alternating antagonistic muscle bursts. Simulations performed with a virtual arm (VA) model indicate that without the PN network, the alternating bursts of antagonistic muscle EMG could not be reliably generated, whereas with the PN network, the alternating pattern of bursts were naturally displayed in the three pairs of antagonist muscles. Thus, it is suggested that oscillations in the primary motor cortex (M1) of single and double tremor frequencies are processed at the PN network to compute the alternating burst pattern in the flexor and extensor muscles.

BATMAN: MOS Spectroscopy on Demand

NASA Astrophysics Data System (ADS)

Molinari, E.; Zamkotsian, F.; Moschetti, M.; Spano, P.; Boschin, W.; Cosentino, R.; Ghedina, A.; González, M.; Pérez, H.; Lanzoni, P.; Ramarijaona, H.; Riva, M.; Zerbi, F.; Nicastro, L.; Valenziano, L.; Di Marcantonio, P.; Coretti, I.; Cirami, R.

2016-10-01

Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and ground-based telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays, which allow the remote control of the multi-slit configuration in real time. TNG is hosting a novelty project for real-time, on-demand MOS masks based on MOEMS programmable slits. We are developing a 2048×1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope, called BATMAN. It is a two-arm instrument designed for providing in parallel imaging and spectroscopic capabilities. With a field of view of 6.8×3.6 arcmin and a plate scale of 0.2 arcsec per micromirror, this astronomical setup can be used to investigate the formation and evolution of galaxies. The wavelength range is in the visible and the spectral resolution is R=560 for a 1 arcsec object, and the two arms will have 2k × 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. We plan to have BATMAN first light by mid-2016.

Optics and optronics in university courses for officers of the Federal Armed Forces - special curricula and hands-on lessons vs. academic requirements

NASA Astrophysics Data System (ADS)

Hahlweg, Cornelius; Rothe, Hendrik

2016-09-01

For more than two decades lessons in optics, digital image processing and optronics are compulsory optional subjects and as such integral parts of the courses in mechanical engineering at the University of the Federal Armed Forces in Hamburg. They are provided by the Chair for Measurement and Information Technology. Historically, the curricula started as typical basic lessons in optics and digital image processing and related sensors. Practical sessions originally concentrated on image processing procedures in Pascal, C and later Matlab. They evolved into a broad portfolio of practical hands-on lessons in lab and field, including high-tech and especially military equipment, but also homemaker style primitive experiments, of which the paper will give a methodical overview. A special topic - as always with optics in education - is the introduction to the various levels of abstraction in conjunction with the highly complex and wide-ranging matter squeezed into only two trimesters - instead of semesters at civil universities - for an audience being subject to strains from both study and duty. The talk will be accompanied by striking multi-media material, which will be also part of the multi-media attachment of the paper.

Reliable Multi Method Assessment of Metacognition Use in Chemistry Problem Solving

ERIC Educational Resources Information Center

Cooper, Melanie M.; Sandi-Urena, Santiago; Stevens, Ron

2008-01-01

Metacognition is fundamental in achieving understanding of chemistry and developing of problem solving skills. This paper describes an across-method-and-time instrument designed to assess the use of metacognition in chemistry problem solving. This multi method instrument combines a self report, namely the Metacognitive Activities Inventory…

Towards a conceptual multi-agent-based framework to simulate the spatial group decision-making process

NASA Astrophysics Data System (ADS)

Ghavami, Seyed Morsal; Taleai, Mohammad

2017-04-01

Most spatial problems are multi-actor, multi-issue and multi-phase in nature. In addition to their intrinsic complexity, spatial problems usually involve groups of actors from different organizational and cognitive backgrounds, all of whom participate in a social structure to resolve or reduce the complexity of a given problem. Hence, it is important to study and evaluate what different aspects influence the spatial problem resolution process. Recently, multi-agent systems consisting of groups of separate agent entities all interacting with each other have been put forward as appropriate tools to use to study and resolve such problems. In this study, then in order to generate a better level of understanding regarding the spatial problem group decision-making process, a conceptual multi-agent-based framework is used that represents and specifies all the necessary concepts and entities needed to aid group decision making, based on a simulation of the group decision-making process as well as the relationships that exist among the different concepts involved. The study uses five main influencing entities as concepts in the simulation process: spatial influence, individual-level influence, group-level influence, negotiation influence and group performance measures. Further, it explains the relationship among different concepts in a descriptive rather than explanatory manner. To illustrate the proposed framework, the approval process for an urban land use master plan in Zanjan—a provincial capital in Iran—is simulated using MAS, the results highlighting the effectiveness of applying an MAS-based framework when wishing to study the group decision-making process used to resolve spatial problems.

Soviet Negotiating Techniques in Arms Control Negotiations with the United States

DTIC Science & Technology

1979-08-01

Arma - ments and the Prohibition of Atomic, Hydrogen and Other Weapons of Mass Destruction. 󈧰 The disarmament debate then centered in twenty- eight...example, on the problem of the Mideast and on other outstanding problems in which the United States and the Soviet Union, acting together, canJ serve the

Cerebellum-inspired neural network solution of the inverse kinematics problem.

PubMed

Asadi-Eydivand, Mitra; Ebadzadeh, Mohammad Mehdi; Solati-Hashjin, Mehran; Darlot, Christian; Abu Osman, Noor Azuan

2015-12-01

The demand today for more complex robots that have manipulators with higher degrees of freedom is increasing because of technological advances. Obtaining the precise movement for a desired trajectory or a sequence of arm and positions requires the computation of the inverse kinematic (IK) function, which is a major problem in robotics. The solution of the IK problem leads robots to the precise position and orientation of their end-effector. We developed a bioinspired solution comparable with the cerebellar anatomy and function to solve the said problem. The proposed model is stable under all conditions merely by parameter determination, in contrast to recursive model-based solutions, which remain stable only under certain conditions. We modified the proposed model for the simple two-segmented arm to prove the feasibility of the model under a basic condition. A fuzzy neural network through its learning method was used to compute the parameters of the system. Simulation results show the practical feasibility and efficiency of the proposed model in robotics. The main advantage of the proposed model is its generalizability and potential use in any robot.

Fuzzy multi objective transportation problem – evolutionary algorithm approach

NASA Astrophysics Data System (ADS)

Karthy, T.; Ganesan, K.

2018-04-01

This paper deals with fuzzy multi objective transportation problem. An fuzzy optimal compromise solution is obtained by using Fuzzy Genetic Algorithm. A numerical example is provided to illustrate the methodology.

Experiments in cooperative manipulation: A system perspective

NASA Technical Reports Server (NTRS)

Schneider, Stanley A.; Cannon, Robert H., Jr.

1989-01-01

In addition to cooperative dynamic control, the system incorporates real time vision feedback, a novel programming technique, and a graphical high level user interface. By focusing on the vertical integration problem, not only these subsystems are examined, but also their interfaces and interactions. The control system implements a multi-level hierarchical structure; the techniques developed for operator input, strategic command, and cooperative dynamic control are presented. At the highest level, a mouse-based graphical user interface allows an operator to direct the activities of the system. Strategic command is provided by a table-driven finite state machine; this methodology provides a powerful yet flexible technique for managing the concurrent system interactions. The dynamic controller implements object impedance control; an extension of Nevill Hogan's impedance control concept to cooperative arm manipulation of a single object. Experimental results are presented, showing the system locating and identifying a moving object catching it, and performing a simple cooperative assembly. Results from dynamic control experiments are also presented, showing the controller's excellent dynamic trajectory tracking performance, while also permitting control of environmental contact force.

Mapping of the human upper arm muscle activity with an electrode matrix.

PubMed

Côté, J; Mathieu, P A

2000-06-01

Surface electrode matrices allow measurement of muscle activity while avoiding certain hazardous risks and inconvenience associated with invasive techniques. Major challenges of such equipment involve optimizing spatial resolution, and designing simple acquisition systems able to record simultaneously many potentials over large anatomical areas. We present a surface electromyography acquisition system comprising of 3 x 8 Ag-AgCl electrodes mounted onto an elastic band, which can be adjusted to fit an entire human upper limb segment. Using this equipment, we acquired a simultaneous representation of muscular activity from a segment of the upper limb surface of 6 healthy subjects during isometric contractions at various intensities. We found that the location of regions of highest activity depended on elbow torque direction but also varied among subjects. Signals obtained with such equipment can be used to solve the inverse problem and help optimize the electrode configuration in volume conduction studies. The efficacy of decision algorithms of multi-functional myoelectric prostheses can be tested with the global muscle activity patterns gathered. The electrode cuff could also be used in the investigation of fatigue and injury mechanisms during occupational activities.

Real-time simulation of three-dimensional shoulder girdle and arm dynamics.

PubMed

Chadwick, Edward K; Blana, Dimitra; Kirsch, Robert F; van den Bogert, Antonie J

2014-07-01

Electrical stimulation is a promising technology for the restoration of arm function in paralyzed individuals. Control of the paralyzed arm under electrical stimulation, however, is a challenging problem that requires advanced controllers and command interfaces for the user. A real-time model describing the complex dynamics of the arm would allow user-in-the-loop type experiments where the command interface and controller could be assessed. Real-time models of the arm previously described have not included the ability to model the independently controlled scapula and clavicle, limiting their utility for clinical applications of this nature. The goal of this study therefore was to evaluate the performance and mechanical behavior of a real-time, dynamic model of the arm and shoulder girdle. The model comprises seven segments linked by eleven degrees of freedom and actuated by 138 muscle elements. Polynomials were generated to describe the muscle lines of action to reduce computation time, and an implicit, first-order Rosenbrock formulation of the equations of motion was used to increase simulation step-size. The model simulated flexion of the arm faster than real time, simulation time being 92% of actual movement time on standard desktop hardware. Modeled maximum isometric torque values agreed well with values from the literature, showing that the model simulates the moment-generating behavior of a real human arm. The speed of the model enables experiments where the user controls the virtual arm and receives visual feedback in real time. The ability to optimize potential solutions in simulation greatly reduces the burden on the user during development.

Service-Oriented Node Scheduling Scheme for Wireless Sensor Networks Using Markov Random Field Model

PubMed Central

Cheng, Hongju; Su, Zhihuang; Lloret, Jaime; Chen, Guolong

2014-01-01

Future wireless sensor networks are expected to provide various sensing services and energy efficiency is one of the most important criterions. The node scheduling strategy aims to increase network lifetime by selecting a set of sensor nodes to provide the required sensing services in a periodic manner. In this paper, we are concerned with the service-oriented node scheduling problem to provide multiple sensing services while maximizing the network lifetime. We firstly introduce how to model the data correlation for different services by using Markov Random Field (MRF) model. Secondly, we formulate the service-oriented node scheduling issue into three different problems, namely, the multi-service data denoising problem which aims at minimizing the noise level of sensed data, the representative node selection problem concerning with selecting a number of active nodes while determining the services they provide, and the multi-service node scheduling problem which aims at maximizing the network lifetime. Thirdly, we propose a Multi-service Data Denoising (MDD) algorithm, a novel multi-service Representative node Selection and service Determination (RSD) algorithm, and a novel MRF-based Multi-service Node Scheduling (MMNS) scheme to solve the above three problems respectively. Finally, extensive experiments demonstrate that the proposed scheme efficiently extends the network lifetime. PMID:25384005

Efficacy of EMG-triggered electrical arm stimulation in chronic hemiparetic stroke patients.

PubMed

von Lewinski, Friederike; Hofer, Sabine; Kaus, Jürgen; Merboldt, Klaus-Dietmar; Rothkegel, Holger; Schweizer, Renate; Liebetanz, David; Frahm, Jens; Paulus, Walter

2009-01-01

EMG-triggered electrostimulation (EMG-ES) may improve the motor performance of affected limbs of hemiparetic stroke patients even in the chronic stage. This study was designed to characterize cortical activation changes following intensified EMG-ES in chronic stroke patients and to identify predictors for successful rehabilitation depending on disease severity. We studied 9 patients with severe residual hemiparesis, who underwent 8 weeks of daily task-orientated multi-channel EMG-ES of the paretic arm. Before and after treatment, arm function was evaluated clinically and cortical activation patterns were assessed with functional MRI (fMRI) and/or transcranial magnetic stimulation (TMS). As response to therapy, arm function improved in a subset of patients with more capacity in less affected subjects, but there was no significant gain for those with Box & Block test values below 4 at inception. The clinical improvement, if any, was accompanied by an ipsilesional increase in the sensorimotor cortex (SMC) activation area in fMRI and enhanced intracortical facilitation (ICF) as revealed by paired TMS. The SMC activation change in fMRI was predicted by the presence or absence of motor-evoked potentials (MEPs) on the affected side. The present findings support the notion that intensified EMG-ES may improve the arm function in individual chronic hemiparetic stroke patients but not in more severely impaired individuals. Functional improvements are paralleled by increased ipsilesional SMC activation and enhanced ICF supporting neuroplasticity as contributor to rehabilitation. The clinical score at inception and the presence of MEPs have the best predictive potential.

Pricing and location decisions in multi-objective facility location problem with M/M/m/k queuing systems

NASA Astrophysics Data System (ADS)

Tavakkoli-Moghaddam, Reza; Vazifeh-Noshafagh, Samira; Taleizadeh, Ata Allah; Hajipour, Vahid; Mahmoudi, Amin

2017-01-01

This article presents a new multi-objective model for a facility location problem with congestion and pricing policies. This model considers situations in which immobile service facilities are congested by a stochastic demand following M/M/m/k queues. The presented model belongs to the class of mixed-integer nonlinear programming models and NP-hard problems. To solve such a hard model, a new multi-objective optimization algorithm based on a vibration theory, namely multi-objective vibration damping optimization (MOVDO), is developed. In order to tune the algorithms parameters, the Taguchi approach using a response metric is implemented. The computational results are compared with those of the non-dominated ranking genetic algorithm and non-dominated sorting genetic algorithm. The outputs demonstrate the robustness of the proposed MOVDO in large-sized problems.

A dynamic model for generating actuator specifications for small arms barrel active stabilization

NASA Astrophysics Data System (ADS)

Pathak, Anupam; Brei, Diann; Luntz, Jonathan; Lavigna, Chris

2006-03-01

Due to stresses encountered in combat, it is known that soldier marksmanship noticeably decreases regardless of prior training. Active stabilization systems in small arms have potential to address this problem to increase soldier survivability and mission effectiveness. The key to success is proper actuator design, but this is highly dependent on proper specification which is challenging due to the human/weapon interaction. This paper presents a generic analytical dynamic model which is capable of defining the necessary actuation specifications for a wide range of small arms platforms. The model is unique because it captures the human interface--shoulder and arm--that introduces the jitter disturbance in addition to the geometry, inertial properties and active stabilization stiffness of the small arms platform. Because no data to date is available for actual shooter-induced disturbance in field conditions, a method is given using the model to back-solve from measured shooting range variability data the disturbance amplitude information relative to the input source (arm or shoulder). As examples of the applicability of the model to various small arms systems, two different weapon systems were investigated: the M24 sniper weapon and the M16 assault rifle. In both cases, model based simulations provided valuable insight into impact on the actuation specifications (force, displacement, phase, frequency) due to the interplay of the human-weapon-active stabilization interface including the effect of shooter-disturbance frequency, disturbance location (shoulder vs. arm), and system parameters (stiffness, barrel rotation).

New approaches in cataloging and distributing multi-dimensional scientific data: Federal Data Repositories example

NASA Astrophysics Data System (ADS)

Devarakonda, R.; Thornton, M.; Wei, Y.; Krishna, B.; Frame, M. T.; Zolly, L.; Records, R.; Palanisamy, G.

2016-12-01

Observational data should be collected and stored logical and scalable way. Most of the time, observation data capture variables or measurements at an exact point in time and are thus not reproducible. It is therefore imperative that initial data be captured and stored correctly the first time. In this paper, we will discuss how big federal data centers and repositories such as DOE's Atmospheric Radiation Measurement (ARM), NASA's Distributed Active Archive Center (DAAC) and the USGS's Science Data Catalog (SDC) at Oak Ridge National Laboratory are preparing, storing and distributing huge multi-dimensional scientific data. We will discuss tools and services, including data formats, that are being used within the ORNL DAAC for managing huge data sets such as Daymet, which provides gridded estimates of various daily weather parameters at a 1km x 1km resolution. Recently released, the Daymet version 3[1] data set covers the period from January 1, 1980 to December 31 2015 for North America and Hawaii: including Canada, Mexico, the United States of America, Puerto Rico, and Bermuda. We will also discuss the latest tools and services within ARM and SDC that are built on popular open source software such as Apache Solr 6, Cassandra, Spark, etc. The ARM Data center (http://www.archive.arm.gov/discovery) archives and distributes various data streams, which are collected through the routine operations and scientific field experiments of the ARM Climate Research Facility. The SDC (http://data.usgs.gov/datacatalog/) provides seamless access to USGS research and monitoring data from across the nation. Every month, tens of thousands of users download portions of these datasets totaling to several TBs/month. The popularity of the data result from many characteristics, but at the forefront is the careful consideration of community needs both in terms of data content and accessibility. Fundamental to this is adherence to data archive and distribution best practices providing open, standardized, and self-describing data which enables development of specialized tools and web services. References: [1] Thornton, P.E., M.M. Thornton, B.W. Mayer, Y. Wei, R. Devarakonda, R.S. Vose, and R.B. Cook. 2016. Daymet: Daily Surface Weather Data on a 1-km Grid for North America, Version 3. ORNL DAAC, Oak Ridge, Tennessee, USA.

Kalman Filter Tracking on Parallel Architectures

NASA Astrophysics Data System (ADS)

Cerati, Giuseppe; Elmer, Peter; Krutelyov, Slava; Lantz, Steven; Lefebvre, Matthieu; McDermott, Kevin; Riley, Daniel; Tadel, Matevž; Wittich, Peter; Würthwein, Frank; Yagil, Avi

2016-11-01

Power density constraints are limiting the performance improvements of modern CPUs. To address this we have seen the introduction of lower-power, multi-core processors such as GPGPU, ARM and Intel MIC. In order to achieve the theoretical performance gains of these processors, it will be necessary to parallelize algorithms to exploit larger numbers of lightweight cores and specialized functions like large vector units. Track finding and fitting is one of the most computationally challenging problems for event reconstruction in particle physics. At the High-Luminosity Large Hadron Collider (HL-LHC), for example, this will be by far the dominant problem. The need for greater parallelism has driven investigations of very different track finding techniques such as Cellular Automata or Hough Transforms. The most common track finding techniques in use today, however, are those based on a Kalman filter approach. Significant experience has been accumulated with these techniques on real tracking detector systems, both in the trigger and offline. They are known to provide high physics performance, are robust, and are in use today at the LHC. Given the utility of the Kalman filter in track finding, we have begun to port these algorithms to parallel architectures, namely Intel Xeon and Xeon Phi. We report here on our progress towards an end-to-end track reconstruction algorithm fully exploiting vectorization and parallelization techniques in a simplified experimental environment.

On Motion Planning and Control of Multi-Link Lightweight Robotic Manipulators

NASA Technical Reports Server (NTRS)

Cetinkunt, Sabri

1987-01-01

A general gross and fine motion planning and control strategy is needed for lightweight robotic manipulator applications such as painting, welding, material handling, surface finishing, and spacecraft servicing. The control problem of lightweight manipulators is to perform fast, accurate, and robust motions despite the payload variations, structural flexibility, and other environmental disturbances. Performance of the rigid manipulator model based computed torque and decoupled joint control methods are determined and simulated for the counterpart flexible manipulators. A counterpart flexible manipulator is defined as a manipulator which has structural flexibility, in addition to having the same inertial, geometric, and actuation properties of a given rigid manipulator. An adaptive model following control (AMFC) algorithm is developed to improve the performance in speed, accuracy, and robustness. It is found that the AMFC improves the speed performance by a factor of two over the conventional non-adaptive control methods for given accuracy requirements while proving to be more robust with respect to payload variations. Yet there are clear limitations on the performance of AMFC alone as well, which are imposed by the arm flexibility. In the search to further improve speed performance while providing a desired accuracy and robustness, a combined control strategy is developed. Furthermore, the problem of switching from one control structure to another during the motion and implementation aspects of combined control are discussed.

Modeling and Optimization of Multiple Unmanned Aerial Vehicles System Architecture Alternatives

PubMed Central

Wang, Weiping; He, Lei

2014-01-01

Unmanned aerial vehicle (UAV) systems have already been used in civilian activities, although very limitedly. Confronted different types of tasks, multi UAVs usually need to be coordinated. This can be extracted as a multi UAVs system architecture problem. Based on the general system architecture problem, a specific description of the multi UAVs system architecture problem is presented. Then the corresponding optimization problem and an efficient genetic algorithm with a refined crossover operator (GA-RX) is proposed to accomplish the architecting process iteratively in the rest of this paper. The availability and effectiveness of overall method is validated using 2 simulations based on 2 different scenarios. PMID:25140328

Well-posed and stable transmission problems

NASA Astrophysics Data System (ADS)

Nordström, Jan; Linders, Viktor

2018-07-01

We introduce the notion of a transmission problem to describe a general class of problems where different dynamics are coupled in time. Well-posedness and stability are analysed for continuous and discrete problems using both strong and weak formulations, and a general transmission condition is obtained. The theory is applied to the coupling of fluid-acoustic models, multi-grid implementations, adaptive mesh refinements, multi-block formulations and numerical filtering.

Asteroid Redirect Mission Concept: A Bold Approach for Utilizing Space Resources

NASA Technical Reports Server (NTRS)

Mazanek, Daniel D.; Merrill, Raymond G.; Brophy, John R.; Mueller, Robert P.

2014-01-01

The utilization of natural resources from asteroids is an idea that is older than the Space Age. The technologies are now available to transform this endeavour from an idea into reality. The Asteroid Redirect Mission (ARM) is a mission concept which includes the goal of robotically returning a small Near-Earth Asteroid (NEA) or a multi-ton boulder from a large NEA to cislunar space in the mid 2020's using an advanced Solar Electric Propulsion (SEP) vehicle and currently available technologies. The paradigm shift enabled by the ARM concept would allow in-situ resource utilization (ISRU) to be used at the human mission departure location (i.e., cislunar space) versus exclusively at the deep-space mission destination. This approach drastically reduces the barriers associated with utilizing ISRU for human deep-space missions. The successful testing of ISRU techniques and associated equipment could enable large-scale commercial ISRU operations to become a reality and enable a future space-based economy utilizing processed asteroidal materials. This paper provides an overview of the ARM concept and discusses the mission objectives, key technologies, and capabilities associated with the mission, as well as how the ARM and associated operations would benefit humanity's quest for the exploration and settlement of space.

Association between delivery methods for red blood cell transfusion and the risk of venous thromboembolism: a longitudinal study.

PubMed

Rogers, Mary A M; Blumberg, Neil; Bernstein, Steven J; Flanders, Scott A; Chopra, Vineet

2016-12-01

Mechanisms of red blood cell delivery and their contribution to the incidence of venous thromboembolism are not well understood in the clinical setting. We assessed whether red blood cell transfusion through peripherally inserted central catheters (PICCs) affects the risk of venous thromboembolism compared with transfusion through non-PICC devices. We implemented a prospective study between Jan 1, 2013, and Sept 12, 2015, in patients (age ≥18 years) admitted to a general medicine ward or intensive care unit who received a PICC for any reason during clinical care in 47 hospitals in Michigan, USA, with a maximum follow-up of 70 days. The exposure of interest was route of red blood cell transfusion. The primary outcome was symptomatic, radiographically confirmed, deep-vein thrombosis in the arm or leg or pulmonary embolism. We used Cox proportional hazards regression for analyses. Venous thromboembolism developed in 482 (5%) of 10 604 patients with PICCs. Of 788 patients who received a red blood cell transfusion through a multi-lumen PICC, 61 had venous thromboembolism. The adjusted hazard ratio (HR) for venous thromboembolism in all patients whose transfusions were administered through a multi-lumen PICC was 1·96 (95% CI 1·47-2·61; p<0·0001) compared with patients not receiving a transfusion, and was 1·79 (1·09-2·95; p=0·022) compared with patients transfused through a peripheral intravenous line. Compared with delivery through a peripheral intravenous line, venous thromboembolism risk was not elevated if transfusions were delivered through a single-lumen PICC (HR 0·98, 95% CI 0·44-2·14; p=0·95) or central venous catheter (1·50, 0·77-2·91; p=0·23). For every red blood cell unit transfused through a PICC, there was a significantly increased risk of venous thromboembolism (adjusted HR 1·24, 95% CI 1·01-1·52; p=0·037). Patients who received a transfusion through a PICC in the left arm were significantly more likely to develop a deep-vein thrombosis in the ipsilateral arm compared with the contralateral side (HR 23·44, 95% CI 2·96-185·83; p=0·0028). Similarly, patients transfused through a right-sided PICC were more likely to develop deep-vein thrombosis in the ipsilateral arm (HR 3·37, 95% CI 1·02-11·14; p=0·047). Red blood cell delivery through a multi-lumen PICC is associated with a greater risk of thrombosis than transfusion through a peripheral intravenous catheter. Careful monitoring for venous thromboembolism when transfusing red blood cells through multi-lumen PICCs seems necessary. Blue Cross Blue Shield of Michigan and Blue Care Network, as part of the BCBSM Value Partnerships program. Copyright © 2016 Elsevier Ltd. All rights reserved.

Two-phase framework for near-optimal multi-target Lambert rendezvous

NASA Astrophysics Data System (ADS)

Bang, Jun; Ahn, Jaemyung

2018-03-01

This paper proposes a two-phase framework to obtain a near-optimal solution of multi-target Lambert rendezvous problem. The objective of the problem is to determine the minimum-cost rendezvous sequence and trajectories to visit a given set of targets within a maximum mission duration. The first phase solves a series of single-target rendezvous problems for all departure-arrival object pairs to generate the elementary solutions, which provides candidate rendezvous trajectories. The second phase formulates a variant of traveling salesman problem (TSP) using the elementary solutions prepared in the first phase and determines the final rendezvous sequence and trajectories of the multi-target rendezvous problem. The validity of the proposed optimization framework is demonstrated through an asteroid exploration case study.

Randomised controlled trial of exercise to prevent shoulder problems in women undergoing breast cancer treatment: study protocol for the prevention of shoulder problems trial (UK PROSPER)

PubMed Central

Williamson, Esther; Lait, Clare; Richmond, Helen; Betteley, Lauren; Lall, Ranjit; Petrou, Stavros; Rees, Sophie; Withers, Emma J; Lamb, Sarah E; Thompson, Alastair M

2018-01-01

Musculoskeletal shoulder problems are common after breast cancer treatment. Early postoperative exercises targeting the upper limb may improve shoulder function. This protocol describes a National Institute for Health Research-funded randomised controlled trial (RCT) to evaluate the clinical and cost-effectiveness of an early supervised structured exercise programme compared with usual care, for women at high risk of developing shoulder problems after breast cancer surgery. Methods This pragmatic two-armed, multicentre RCT is underway within secondary care in the UK. PRevention Of Shoulder ProblEms tRial (PROSPER) aims to recruit 350 women from approximately 15 UK centres with follow-up at 6 weeks, 6 and 12 months after randomisation. Recruitment processes and intervention development were optimised through qualitative research during a 6-month internal pilot phase. Participants are randomised to the PROSPER intervention or best practice usual care only. The PROSPER intervention is delivered by physiotherapists and incorporates three main components: shoulder-specific exercises targeting range of movement and strength; general physical activity and behavioural strategies to encourage adherence and support exercise behaviour. The primary outcome is upper arm function assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire at 12 months postrandomisation. Secondary outcomes include DASH subscales, acute and chronic pain, complications, health-related quality of life and healthcare resource use. We will interview a subsample of 20 participants to explore their experiences of the trial interventions. Discussion The PROSPER study is the first multicentre UK clinical trial to investigate the clinical and cost-effectiveness of supported exercise in the prevention of shoulder problems in high-risk women undergoing breast cancer surgery. The findings will inform future clinical practice and provide valuable insight into the role of physiotherapy-supported exercise in breast cancer rehabilitation. Protocol version Version 2.1; dated 11 January 2017 Trial registration number ISRCTN35358984; Pre-results. PMID:29574439

A Coral Reef Algorithm Based on Learning Automata for the Coverage Control Problem of Heterogeneous Directional Sensor Networks

PubMed Central

Li, Ming; Miao, Chunyan; Leung, Cyril

2015-01-01

Coverage control is one of the most fundamental issues in directional sensor networks. In this paper, the coverage optimization problem in a directional sensor network is formulated as a multi-objective optimization problem. It takes into account the coverage rate of the network, the number of working sensor nodes and the connectivity of the network. The coverage problem considered in this paper is characterized by the geographical irregularity of the sensed events and heterogeneity of the sensor nodes in terms of sensing radius, field of angle and communication radius. To solve this multi-objective problem, we introduce a learning automata-based coral reef algorithm for adaptive parameter selection and use a novel Tchebycheff decomposition method to decompose the multi-objective problem into a single-objective problem. Simulation results show the consistent superiority of the proposed algorithm over alternative approaches. PMID:26690162

A Coral Reef Algorithm Based on Learning Automata for the Coverage Control Problem of Heterogeneous Directional Sensor Networks.

PubMed

Li, Ming; Miao, Chunyan; Leung, Cyril

2015-12-04

Coverage control is one of the most fundamental issues in directional sensor networks. In this paper, the coverage optimization problem in a directional sensor network is formulated as a multi-objective optimization problem. It takes into account the coverage rate of the network, the number of working sensor nodes and the connectivity of the network. The coverage problem considered in this paper is characterized by the geographical irregularity of the sensed events and heterogeneity of the sensor nodes in terms of sensing radius, field of angle and communication radius. To solve this multi-objective problem, we introduce a learning automata-based coral reef algorithm for adaptive parameter selection and use a novel Tchebycheff decomposition method to decompose the multi-objective problem into a single-objective problem. Simulation results show the consistent superiority of the proposed algorithm over alternative approaches.

The use of multi-criteria decision analysis to tackle waste management problems: a literature review.

PubMed

Achillas, Charisios; Moussiopoulos, Nicolas; Karagiannidis, Avraam; Banias, Georgias; Perkoulidis, George

2013-02-01

Problems in waste management have become more and more complex during recent decades. The increasing volumes of waste produced and social environmental consciousness present prominent drivers for environmental managers towards the achievement of a sustainable waste management scheme. However, in practice, there are many factors and influences - often mutually conflicting - criteria for finding solutions in real-life applications. This paper presents a review of the literature on multi-criteria decision aiding in waste management problems for all reported waste streams. Despite limitations, which are clearly stated, most of the work published in this field is reviewed. The present review aims to provide environmental managers and decision-makers with a thorough list of practical applications of the multi-criteria decision analysis techniques that are used to solve real-life waste management problems, as well as the criteria that are mostly employed in such applications according to the nature of the problem under study. Moreover, the paper explores the advantages and disadvantages of using multi-criteria decision analysis techniques in waste management problems in comparison to other available alternatives.

Central implementation strategies outperform local ones in improving HIV testing in Veterans Healthcare Administration facilities.

PubMed

Goetz, Matthew Bidwell; Hoang, Tuyen; Knapp, Herschel; Burgess, Jane; Fletcher, Michael D; Gifford, Allen L; Asch, Steven M

2013-10-01

Pilot data suggest that a multifaceted approach may increase HIV testing rates, but the scalability of this approach and the level of support needed for successful implementation remain unknown. To evaluate the effectiveness of a scaled-up multi-component intervention in increasing the rate of risk-based and routine HIV diagnostic testing in primary care clinics and the impact of differing levels of program support. Three arm, quasi-experimental implementation research study. Veterans Health Administration (VHA) facilities. Persons receiving primary care between June 2009 and September 2011 INTERVENTION: A multimodal program, including a real-time electronic clinical reminder to facilitate HIV testing, provider feedback reports and provider education, was implemented in Central and Local Arm Sites; sites in the Central Arm also received ongoing programmatic support. Control Arm sites had no intervention Frequency of performing HIV testing during the 6 months before and after implementation of a risk-based clinical reminder (phase I) or routine clinical reminder (phase II). The adjusted rate of risk-based testing increased by 0.4 %, 5.6 % and 10.1 % in the Control, Local and Central Arms, respectively (all comparisons, p < 0.01). During phase II, the adjusted rate of routine testing increased by 1.1 %, 6.3 % and 9.2 % in the Control, Local and Central Arms, respectively (all comparisons, p < 0.01). At study end, 70-80 % of patients had been offered an HIV test. Use of clinical reminders, provider feedback, education and social marketing significantly increased the frequency at which HIV testing is offered and performed in VHA facilities. These findings support a multimodal approach toward achieving the goal of having every American know their HIV status as a matter of routine clinical practice.

Samarium-153-EDTMP (Quadramet®) with or without vaccine in metastatic castration-resistant prostate cancer: A randomized Phase 2 trial.

PubMed

Heery, Christopher R; Madan, Ravi A; Stein, Mark N; Stadler, Walter M; Di Paola, Robert S; Rauckhorst, Myrna; Steinberg, Seth M; Marté, Jennifer L; Chen, Clara C; Grenga, Italia; Donahue, Renee N; Jochems, Caroline; Dahut, William L; Schlom, Jeffrey; Gulley, James L

2016-10-18

PSA-TRICOM is a therapeutic vaccine in late stage clinical testing in metastatic castration-resistant prostate cancer (mCRPC). Samarium-153-ethylene diamine tetramethylene phosphonate (Sm-153-EDTMP; Quadramet®), a radiopharmaceutical, binds osteoblastic bone lesions and emits beta particles causing local tumor cell destruction. Preclinically, Sm-153-EDTMP alters tumor cell phenotype facilitating immune-mediated killing. This phase 2 multi-center trial randomized patients to Sm-153-EDTMP alone or with PSA-TRICOM vaccine. Eligibility required mCRPC, bone metastases, prior docetaxel and no visceral disease. The primary endpoint was the proportion of patients without radiographic disease progression at 4 months. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and immune responses. Forty-four patients enrolled. Eighteen and 21 patients were evaluable for the primary endpoint in Sm-153-EDTMP alone and combination arms, respectively. There was no statistical difference in the primary endpoint, with two of 18 (11.1%) and five of 21 (23.8%) in Sm-153-EDTMP alone and combination arms, respectively, having stable disease at approximately the 4-month evaluation time point (P = 0.27). Median PFS was 1.7 vs. 3.7 months in the Sm-153-EDTMP alone and combination arms (P = 0.041, HR = 0.51, P = 0.046). No patient in the Sm-153-EDTMP alone arm achieved prostate-specific antigen (PSA) decline > 30% compared with four patients (of 21) in the combination arm, including three with PSA decline > 50%. Toxicities were similar between arms and related to number of Sm-153-EDTMP doses administered. These results provide the rationale for clinical evaluation of new radiopharmaceuticals, such as Ra-223, in combination with PSA-TRICOM.

Samarium-153-EDTMP (Quadramet®) with or without vaccine in metastatic castration-resistant prostate cancer: A randomized Phase 2 trial

PubMed Central

Heery, Christopher R.; Madan, Ravi A.; Stein, Mark N.; Stadler, Walter M.; Di Paola, Robert S.; Rauckhorst, Myrna; Steinberg, Seth M.; Marté, Jennifer L.; Chen, Clara C.; Grenga, Italia; Donahue, Renee N.; Jochems, Caroline; Dahut, William L.; Schlom, Jeffrey; Gulley, James L.

2016-01-01

PSA-TRICOM is a therapeutic vaccine in late stage clinical testing in metastatic castration-resistant prostate cancer (mCRPC). Samarium-153-ethylene diamine tetramethylene phosphonate (Sm-153-EDTMP; Quadramet®), a radiopharmaceutical, binds osteoblastic bone lesions and emits beta particles causing local tumor cell destruction. Preclinically, Sm-153-EDTMP alters tumor cell phenotype facilitating immune-mediated killing. This phase 2 multi-center trial randomized patients to Sm-153-EDTMP alone or with PSA-TRICOM vaccine. Eligibility required mCRPC, bone metastases, prior docetaxel and no visceral disease. The primary endpoint was the proportion of patients without radiographic disease progression at 4 months. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and immune responses. Forty-four patients enrolled. Eighteen and 21 patients were evaluable for the primary endpoint in Sm-153-EDTMP alone and combination arms, respectively. There was no statistical difference in the primary endpoint, with two of 18 (11.1%) and five of 21 (23.8%) in Sm-153-EDTMP alone and combination arms, respectively, having stable disease at approximately the 4-month evaluation time point (P = 0.27). Median PFS was 1.7 vs. 3.7 months in the Sm-153-EDTMP alone and combination arms (P = 0.041, HR = 0.51, P = 0.046). No patient in the Sm-153-EDTMP alone arm achieved prostate-specific antigen (PSA) decline > 30% compared with four patients (of 21) in the combination arm, including three with PSA decline > 50%. Toxicities were similar between arms and related to number of Sm-153-EDTMP doses administered. These results provide the rationale for clinical evaluation of new radiopharmaceuticals, such as Ra-223, in combination with PSA-TRICOM. PMID:27486817

Metformin and/or Clomiphene Do Not Adversely Affect Liver or Renal Function in Women with Polycystic Ovary Syndrome

PubMed Central

Aubuchon, Mira; Kunselman, Allen R.; Schlaff, William D.; Diamond, Michael P.; Coutifaris, Christos; Carson, Sandra A.; Steinkampf, Michael P.; Carr, Bruce R.; McGovern, Peter G.; Cataldo, Nicholas A.; Gosman, Gabriella G.; Nestler, John E.; Myers, Evan R.

2011-01-01

Context: Nonalcoholic fatty liver disease is common to insulin-resistant states such as polycystic ovary syndrome (PCOS). Metformin (MET) is often used to treat PCOS but information is limited as to its effects on liver function. Objective: We sought to determine the effects of MET on serum hepatic parameters in PCOS patients. Design: This was a secondary analysis of a randomized, doubled-blind trial from 2002–2004. Setting: This multi-center clinical trial was conducted in academic centers. Patients: Six hundred twenty-six infertile women with PCOS with serum liver function parameters less than twice the upper limit of normal were included. Interventions: Clomiphene citrate (n = 209), MET (n = 208), or combined (n = 209) were given for up to 6 months. Main Outcome Measure: The percent change from baseline in renal and liver function between- and within-treatment arms was assessed. Results: Renal function improved in all treatment arms with significant decreases in serum blood urea nitrogen levels (range, −14.7 to −21.3%) as well as creatinine (−4.2 to −6.9%). There were similar decreases in liver transaminase levels in the clomiphene citrate and combined arms (−10% in bilirubin, −9 to −11% in transaminases) without significant changes in the MET arm. When categorizing baseline bilirubin, aspartate aminotransferase, and alanine aminotransferase into tertiles, there were significant within-treatment arm differences between the tertiles with the highest tertile having the largest decrease from baseline regardless of treatment arm. Conclusion: Women with PCOS can safely use metformin and clomiphene even in the setting of mildly abnormal liver function parameters, and both result in improved renal function. PMID:21832111

Maintenance sunitinib or observation in metastatic pancreatic adenocarcinoma: a phase II randomised trial.

PubMed

Reni, Michele; Cereda, Stefano; Milella, Michele; Novarino, Anna; Passardi, Alessandro; Mambrini, Andrea; Di Lucca, Giuseppe; Aprile, Giuseppe; Belli, Carmen; Danova, Marco; Bergamo, Francesca; Franceschi, Enrico; Fugazza, Clara; Ceraulo, Domenica; Villa, Eugenio

2013-11-01

New strategies to prolong disease control warrant investigation in patients with metastatic pancreatic adenocarcinoma. This open-label, randomised, multi-centre phase II trial explored the role of maintenance sunitinib after first-line chemotherapy in this setting. Patients with pathologic diagnosis of metastatic pancreatic adenocarcinoma, performance status >50%, no progression after 6 months of chemotherapy were centrally randomised by an independent contract research organisation, which was also responsible for data collection and monitoring, to observation (arm A) or sunitinib at 37.5mg daily until progression or a maximum of 6 months (arm B). The primary outcome measure was the probability of being progression-free at 6 months (PFS-6) from randomisation. Assuming P0 = 10%; P1 = 30%, α .10; β .10, the target accrual was 26 patients per arm. 28 per arm were randomised. One arm B patient had kidney cancer and was excluded. Sunitinib was given for a median of 91 days (7-186). Main grade 3-4 toxicity was thrombocytopenia, neutropenia and hand-foot syndrome (12%), diarrhoea 8%. In arm A versus B, PFS-6 was 3.6% (95% confidence interval (CI): 0-10.6%) and 22.2% (95% CI: 6.2-38.2%; P<0.01); 2 y overall survival was 7.1% (95% CI: 0-16.8%) and 22.9% (95% CI: 5.8-40.0%; P = 0.11), stable disease 21.4% and 51.9% (P = 0.02). This is the first randomised trial on maintenance therapy in metastatic pancreatic adenocarcinoma. The primary end-point was fulfilled and 2 y overall survival was remarkably high, suggesting that maintenance sunitinib is promising and should be further explored in this patient population. Copyright © 2013 Elsevier Ltd. All rights reserved.

Automated personalized feedback for physical activity and dietary behavior change with mobile phones: a randomized controlled trial on adults.

PubMed

Rabbi, Mashfiqui; Pfammatter, Angela; Zhang, Mi; Spring, Bonnie; Choudhury, Tanzeem

2015-05-14

A dramatic rise in health-tracking apps for mobile phones has occurred recently. Rich user interfaces make manual logging of users' behaviors easier and more pleasant, and sensors make tracking effortless. To date, however, feedback technologies have been limited to providing overall statistics, attractive visualization of tracked data, or simple tailoring based on age, gender, and overall calorie or activity information. There are a lack of systems that can perform automated translation of behavioral data into specific actionable suggestions that promote healthier lifestyle without any human involvement. MyBehavior, a mobile phone app, was designed to process tracked physical activity and eating behavior data in order to provide personalized, actionable, low-effort suggestions that are contextualized to the user's environment and previous behavior. This study investigated the technical feasibility of implementing an automated feedback system, the impact of the suggestions on user physical activity and eating behavior, and user perceptions of the automatically generated suggestions. MyBehavior was designed to (1) use a combination of automatic and manual logging to track physical activity (eg, walking, running, gym), user location, and food, (2) automatically analyze activity and food logs to identify frequent and nonfrequent behaviors, and (3) use a standard machine-learning, decision-making algorithm, called multi-armed bandit (MAB), to generate personalized suggestions that ask users to either continue, avoid, or make small changes to existing behaviors to help users reach behavioral goals. We enrolled 17 participants, all motivated to self-monitor and improve their fitness, in a pilot study of MyBehavior. In a randomized two-group trial, investigators randomly assigned participants to receive either MyBehavior's personalized suggestions (n=9) or nonpersonalized suggestions (n=8), created by professionals, from a mobile phone app over 3 weeks. Daily activity level and dietary intake was monitored from logged data. At the end of the study, an in-person survey was conducted that asked users to subjectively rate their intention to follow MyBehavior suggestions. In qualitative daily diary, interview, and survey data, users reported MyBehavior suggestions to be highly actionable and stated that they intended to follow the suggestions. MyBehavior users walked significantly more than the control group over the 3 weeks of the study (P=.05). Although some MyBehavior users chose lower-calorie foods, the between-group difference was not significant (P=.15). In a poststudy survey, users rated MyBehavior's personalized suggestions more positively than the nonpersonalized, generic suggestions created by professionals (P<.001). MyBehavior is a simple-to-use mobile phone app with preliminary evidence of efficacy. To the best of our knowledge, MyBehavior represents the first attempt to create personalized, contextualized, actionable suggestions automatically from self-tracked information (ie, manual food logging and automatic tracking of activity). Lessons learned about the difficulty of manual logging and usability concerns, as well as future directions, are discussed. ClinicalTrials.gov NCT02359981; https://clinicaltrials.gov/ct2/show/NCT02359981 (Archived by WebCite at http://www.webcitation.org/6YCeoN8nv).

Breast reduction

MedlinePlus

... may be moved higher to reposition them for cosmetic reasons. In the most common procedure: The surgeon ... numbness or tingling in your arms or hands. Cosmetic problems, such as persistent bra-strap groove, scar- ...

Performance impact of mutation operators of a subpopulation-based genetic algorithm for multi-robot task allocation problems.

PubMed

Liu, Chun; Kroll, Andreas

2016-01-01

Multi-robot task allocation determines the task sequence and distribution for a group of robots in multi-robot systems, which is one of constrained combinatorial optimization problems and more complex in case of cooperative tasks because they introduce additional spatial and temporal constraints. To solve multi-robot task allocation problems with cooperative tasks efficiently, a subpopulation-based genetic algorithm, a crossover-free genetic algorithm employing mutation operators and elitism selection in each subpopulation, is developed in this paper. Moreover, the impact of mutation operators (swap, insertion, inversion, displacement, and their various combinations) is analyzed when solving several industrial plant inspection problems. The experimental results show that: (1) the proposed genetic algorithm can obtain better solutions than the tested binary tournament genetic algorithm with partially mapped crossover; (2) inversion mutation performs better than other tested mutation operators when solving problems without cooperative tasks, and the swap-inversion combination performs better than other tested mutation operators/combinations when solving problems with cooperative tasks. As it is difficult to produce all desired effects with a single mutation operator, using multiple mutation operators (including both inversion and swap) is suggested when solving similar combinatorial optimization problems.

Women in the Military. Hearings before the Military Personnel and Compensation Subcommitee of the Committee on Armed Services, House of Representatives. One Hundredth Congress, First and Second Sessions (October 1, November 19, 1987 and February 4, 1988).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Armed Services.

Within this document is the testimony delivered by 15 individuals at congressional hearings. Among the issues spoken to are: the combat exclusion law and its effect on the careers of women in the military; the kinds of jobs open to female armed services personnel; special problems that women in the military face; their promotion and retention…