scholarly journals Learning an Optimization Algorithm Through Human Design Iterations

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Thurston Sexton ◽  
Max Yi Ren
Keyword(s):  
Optimization Algorithm ◽  
Real World ◽  
Bayesian Optimization ◽  
Search Performance ◽  
Human Beings ◽  
Domain Specific ◽  
Human Participants ◽  
The One ◽  
Lack Of Commitment ◽  
And Control

Solving optimal design problems through crowdsourcing faces a dilemma: On the one hand, human beings have been shown to be more effective than algorithms at searching for good solutions of certain real-world problems with high-dimensional or discrete solution spaces; on the other hand, the cost of setting up crowdsourcing environments, the uncertainty in the crowd's domain-specific competence, and the lack of commitment of the crowd contribute to the lack of real-world application of design crowdsourcing. We are thus motivated to investigate a solution-searching mechanism where an optimization algorithm is tuned based on human demonstrations on solution searching, so that the search can be continued after human participants abandon the problem. To do so, we model the iterative search process as a Bayesian optimization (BO) algorithm and propose an inverse BO (IBO) algorithm to find the maximum likelihood estimators (MLEs) of the BO parameters based on human solutions. We show through a vehicle design and control problem that the search performance of BO can be improved by recovering its parameters based on an effective human search. Thus, IBO has the potential to improve the success rate of design crowdsourcing activities, by requiring only good search strategies instead of good solutions from the crowd.

scholarly journals Some Social Attitudes to Personality with Implications for Psychotherapy

1966 ◽  
Vol 11 (6) ◽  
pp. 492-496 ◽  
Author(s):  
F. W. Hanley
Keyword(s):  
Therapeutic Relationship ◽  
Belief Systems ◽  
Belief System ◽  
Interpersonal Problems ◽  
Social Attitudes ◽  
Human Beings ◽  
Will Power ◽  
The One ◽  
And Control

The patient and the psychiatrist often have different belief systems about personality and its functions. The one held by the patient is derived at least in part, from the values and attitudes toward people of a business-dominated society. Examples of several attitudes are discussed. First, that everyone should be able to solve his own personal and interpersonal problems without assistance. This exaggerated and narrow individualism leads to increasing alienation, reluctance to enter therapy and difficulty in the establishment of a therapeutic relationship. Second, the notion that will power is an entity which can influence and control thoughts, feelings and behaviour leads to much useless effort on the part of the patient. Third, emotions are considered inferior to reason and are distrusted, making the psychiatrist's work of helping patients to recognize and accept their feelings much more difficult. Many self-attitudes are derived from commercial values and the view of human beings as commodities. The belief system derived from business is materialistic, mechanical, limiting and anti-humanistic. The belief system held by the psychiatrist is humanistic and oriented toward a full-valued, integrated individual. These opposing systems may interfere with communication and hence with therapy. The psychiatrist is not always free from the harmful assumptions held by the patient.

A Pragmatist View of Scientific Realism

PARADIGMI ◽  
2010 ◽  
pp. 89-96
Author(s):  
Michele Marsonet
Keyword(s):  
Scientific Realism ◽  
Scientific Progress ◽  
Convergence Theory ◽  
Human Beings ◽  
Long Run ◽  
The World ◽  
History Of ◽  
Prediction And Control ◽  
The One ◽  
And Control

Scientific realism is a theme in which the originality of pragmatist positions clearly emerges. Nicholas Rescher argues that natural science can indeed validate a plausible commitment to the actual existence of its theoretical entities. Scientific conceptions aim at what really exists in the world but only hits it imperfectly and "well off the mark". Rescher's aim is to replace Charles S. Peirce's "long-run convergence" theory of scientific progress with a more modest position geared to increasing success in scientific applications, especially in matters of prediction and control. We can never assume that a particular scientific theory gives us the true picture of reality, since we know perfectly well from the history of science that, in a future we cannot actually foresee, it will be replaced by a better theory. There is indeed no reason to think that our particular scientific outlook on reality is absolute from the cognitive viewpoint. It must be relativized because of the interaction between the world on the one hand and human beings who investigate it on the other. Both our input and Nature's play a fundamental role in the outcome of our investigation.

Learning Human Search Strategies From a Crowdsourcing Game

2016 ◽  
Author(s):  
Thurston Sexton ◽  
Max Yi Ren
Keyword(s):  
Search Strategy ◽  
Bayesian Optimization ◽  
Simulation Studies ◽  
Optimal Solutions ◽  
Solution Path ◽  
Human Beings ◽  
Inverse Reinforcement Learning ◽  
Control Solution ◽  
Learning Capability ◽  
And Control

There is evidence that humans can be more efficient than existing algorithms at searching for good solutions in high-dimensional and non-convex design or control spaces, potentially due to our prior knowledge and learning capability. This work attempts to quantify the search strategy of human beings to enhance a Bayesian optimization (BO) algorithm for an optimal design and control problem. We consider the sequence of human solutions as generated from BO, and propose to recover the algorithmic parameters of BO by maximizing the likelihood of the observed solution path. The method is different from inverse reinforcement learning (where an optimal control solution is learned based on human demonstrations) in that the latter requires near-optimal solutions from humans, while we only require the existence of a good search strategy. The method is first verified through simulation studies and then applied to the human solutions crowdsourced through a gamification of the problem under study [1]. We learn BO parameters from a player with a demonstrated good search strategy and show that applying the BO algorithm with these parameters to the game noticeably improves the convergence of the search from using a default BO setting.

scholarly journals Simheuristics Approaches for Efficient Decision-Making Support in Materials Trading Networks

Algorithms ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 23
Author(s):  
Markus Rabe ◽  
Majsa Ammouriova ◽  
Dominik Schmitt ◽  
Felix Dross
Keyword(s):  
Reinforcement Learning ◽  
Response Time ◽  
Real World ◽  
Computation Time ◽  
Service Level ◽  
Specific Information ◽  
Real World Data ◽  
Domain Specific ◽  
Distribution Process ◽  
The One

The distribution process in business-to-business materials trading is among the most complex and in transparent ones within logistics. The highly volatile environment requires continuous adaptations by the responsible decision-makers, who face a substantial number of potential improvement actions with conflicting goals, such as simultaneously maintaining a high service level and low costs. Simulation-optimisation approaches have been proposed in this context, for example based on evolutionary algorithms. But, on real-world system dimensions, they face impractically long computation times. This paper addresses this challenge in two principal streams. On the one hand, reinforcement learning is investigated to reduce the response time of the system in a concrete decision situation. On the other hand, domain-specific information and defining equivalent solutions are exploited to support a metaheuristic algorithm. For these approaches, we have developed suitable implementations and evaluated them with subsets of real-world data. The results demonstrate that reinforcement learning exploits the idle time between decision situations to learn which decisions might be most promising, thus adding computation time but significantly reducing the response time. Using domain-specific information reduces the number of required simulation runs and guides the search for promising actions. In our experimentation, defining equivalent solutions decreased the number of required simulation runs up to 15%.

Freedom and Responsibility in Neoplatonist Thought

2020 ◽  
Author(s):  
Ursula Coope
Keyword(s):  
First Principle ◽  
Human Beings ◽  
Human Soul ◽  
The One ◽  
Freedom And Responsibility

The Neoplatonists have a perfectionist view of freedom: an entity is free to the extent that it succeeds in making itself good. Free entities are wholly in control of themselves: they are self-determining, self-constituting, and self-knowing. Neoplatonist philosophers argue that such freedom is only possible for nonbodily things. The human soul is free insofar as it rises above bodily things and engages in intellection, but when it turns its desires to bodily things, it is drawn under the sway of fate and becomes enslaved. This book discusses this notion of freedom, and its relation to questions about responsibility. It explains the important role of notions of self-reflexivity in Neoplatonist accounts of both freedom and responsibility. Part I sets out the puzzles Neoplatonist philosophers face about freedom and responsibility and explains how these puzzles arise from earlier discussions. Part II looks at the metaphysical underpinnings of the Neoplatonist notion of freedom (concentrating especially on the views of Plotinus and Proclus). In what sense (if any) is the ultimate first principle of everything (the One) free? If everything else is under this ultimate first principle, how can anything other than the One be free? What is the connection between freedom and nonbodiliness? Part III looks at questions about responsibility, arising from this perfectionist view of freedom. Why are human beings responsible for their behaviour, in a way that other animals are not? If we are enslaved when we act viciously, how can we be to blame for our vicious actions and choices?

An LQ Approach to Active Control of Vibrations in Helicopters

1996 ◽  
Vol 118 (3) ◽  
pp. 482-488 ◽  
Author(s):  
Sergio Bittanti ◽  
Fabrizio Lorito ◽  
Silvia Strada
Keyword(s):  
Optimal Control ◽  
Active Control ◽  
Linear Quadratic ◽  
Control Effort ◽  
Vibration Effect ◽  
Suitable Definition ◽  
Lq Optimal Control ◽  
The One ◽  
Definition Of ◽  
And Control

In this paper, Linear Quadratic (LQ) optimal control concepts are applied for the active control of vibrations in helicopters. The study is based on an identified dynamic model of the rotor. The vibration effect is captured by suitably augmenting the state vector of the rotor model. Then, Kalman filtering concepts can be used to obtain a real-time estimate of the vibration, which is then fed back to form a suitable compensation signal. This design rationale is derived here starting from a rigorous problem position in an optimal control context. Among other things, this calls for a suitable definition of the performance index, of nonstandard type. The application of these ideas to a test helicopter, by means of computer simulations, shows good performances both in terms of disturbance rejection effectiveness and control effort limitation. The performance of the obtained controller is compared with the one achievable by the so called Higher Harmonic Control (HHC) approach, well known within the helicopter community.

scholarly journals Multi-fidelity black-box optimization for time-optimal quadrotor maneuvers

2021 ◽  
pp. 027836492110333
Author(s):  
Gilhyun Ryou ◽  
Ezra Tal ◽  
Sertac Karaman
Keyword(s):  
Real World ◽  
High Speed ◽  
Analytical Approximation ◽  
Black Box ◽  
Bayesian Optimization ◽  
Optimization Framework ◽  
Quadrotor Aircraft ◽  
Time Optimal ◽  
Feasibility Constraints ◽  
Generation Problem

We consider the problem of generating a time-optimal quadrotor trajectory for highly maneuverable vehicles, such as quadrotor aircraft. The problem is challenging because the optimal trajectory is located on the boundary of the set of dynamically feasible trajectories. This boundary is hard to model as it involves limitations of the entire system, including complex aerodynamic and electromechanical phenomena, in agile high-speed flight. In this work, we propose a multi-fidelity Bayesian optimization framework that models the feasibility constraints based on analytical approximation, numerical simulation, and real-world flight experiments. By combining evaluations at different fidelities, trajectory time is optimized while the number of costly flight experiments is kept to a minimum. The algorithm is thoroughly evaluated for the trajectory generation problem in two different scenarios: (1) connecting predetermined waypoints; (2) planning in obstacle-rich environments. For each scenario, we conduct both simulation and real-world flight experiments at speeds up to 11 m/s. Resulting trajectories were found to be significantly faster than those obtained through minimum-snap trajectory planning.

scholarly journals Real-World Experience of the One-Year Efficacy of Rifaximin Add-On to Lactulose Is Superior to Lactulose Alone in Patients with Cirrhosis Complicated with Recurrent Hepatic Encephalopathy in Taiwan

2021 ◽  
Vol 11 (6) ◽  
pp. 478
Author(s):  
Ching Chang ◽  
Chien-Hao Huang ◽  
Hsiao-Jung Tseng ◽  
Fang-Chen Yang ◽  
Rong-Nan Chien
Keyword(s):  
Hepatic Encephalopathy ◽  
Real World ◽  
Ammonia Level ◽  
Decompensated Cirrhosis ◽  
Control Group ◽  
Multivariable Logistic Regression Model ◽  
Before And After ◽  
One Year ◽  
The One ◽  
Serum Ammonia

Background: Hepatic encephalopathy (HE), a neuropsychiatric complication of decompensated cirrhosis, is associated with high mortality and high risk of recurrence. Rifaximin add-on to lactulose for 3 to 6 months is recommended for the prevention of recurrent episodes of HE after the second episode. However, whether the combination for more than 6 months is superior to lactulose alone in the maintenance of HE remission is less evident. Therefore, the aim of this study is to evaluate the one-year efficacy of rifaximin add-on to lactulose for the maintenance of HE remission in Taiwan. Methods: We conducted a real-world single-center retrospective cohort study to compare the long-term efficacy of rifaximin add-on to lactulose (group R + L) versus lactulose alone (group L, control group). Furthermore, the treatment efficacy before and after rifaximin add-on to lactulose was also analyzed. The primary endpoint of our study was time to first HE recurrence (Conn score ≥ 2). All patients were followed up every three months until death, and censored at one year if still alive. Results and Conclusions: 12 patients were enrolled in group R + L. Another 31 patients were stratified into group L. Sex, comorbidity, ammonia level, and ascites grade were matched while age, HE grade, and model for end-stage liver disease (MELD) score were adjusted in the multivariable logistic regression model. Compared with group L, significant improvement in the maintenance of HE remission and decreased episodes and days of HE-related hospitalizations were demonstrated in group R + L. The serum ammonia levels were significantly lower at the 3rd and 6th month in group 1. Concerning changes before and after rifaximin add-on in group R + L, mini-mental status examination (MMSE), episodes of hospitalization, and variceal bleeding also improved at 6 and 12 months. Days of hospitalization, serum ammonia levels also improved at 6th month. Except for concern over price, no patients discontinued rifaximin due to adverse events or complications. The above results provide evidence for the one-year use of rifaximin add-on to lactulose in reducing HE recurrence and HE-related hospitalization for patients with decompensated cirrhosis.

scholarly journals Structural comparison of CD163 SRCR5 from different species sheds some light on its involvement in porcine reproductive and respiratory syndrome virus-2 infection in vitro

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Hongfang Ma ◽  
Rui Li ◽  
Longguang Jiang ◽  
Songlin Qiao ◽  
Xin-xin Chen ◽  
...  
Keyword(s):  
Scavenger Receptor ◽  
Host Cells ◽  
Respiratory Syndrome Virus ◽  
Swine Industry ◽  
Prrs Virus ◽  
Rich Domain ◽  
Serious Disease ◽  
The One ◽  
And Control

AbstractPorcine reproductive and respiratory syndrome (PRRS) is a serious disease burdening global swine industry. Infection by its etiological agent, PRRS virus (PRRSV), shows a highly restricted tropism of host cells and has been demonstrated to be mediated by an essential scavenger receptor (SR) CD163. CD163 fifth SR cysteine-rich domain (SRCR5) is further proven to play a crucial role during viral infection. Despite intense research, the involvement of CD163 SRCR5 in PRRSV infection remains to be elucidated. In the current study, we prepared recombinant monkey CD163 (moCD163) SRCR5 and human CD163-like homolog (hCD163L1) SRCR8, and determined their crystal structures. After comparison with the previously reported crystal structure of porcine CD163 (pCD163) SRCR5, these structures showed almost identical structural folds but significantly different surface electrostatic potentials. Based on these differences, we carried out mutational research to identify that the charged residue at position 534 in association with the one at position 561 were important for PRRSV-2 infection in vitro. Altogether the current work sheds some light on CD163-mediated PRRSV-2 infection and deepens our understanding of the viral pathogenesis, which will provide clues for prevention and control of PRRS.

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