Load alleviation in tilt rotor aircraft through active control; modelling and control concepts

2004 ◽  
Vol 108 (1082) ◽  
pp. 169-184 ◽  
Author(s):  
B. Manimala ◽  
G. D. Padfield ◽  
D. Walker ◽  
M. Naddei ◽  
L. Verde ◽  
...  
Keyword(s):  
Active Control ◽  
Tilt Rotor ◽  
System A ◽  
Critical Technology ◽  
First Results ◽  
Objective Control ◽  
Performance Penalty ◽  
Primary Focus ◽  
High Level ◽  
And Control

This paper presents the first results from research into active control of structural load alleviation (SLA) for tiltrotor aircraft carried out in the European ‘critical technology’ RHILP project. The importance of and the need for SLA in tiltrotors are discussed, drawing on previous US experience reported in the open literature. The paper addresses the modelling aspects in some detail; hence forming the foundation for both the FLIGHTLAB simulated XV-15 and EUROTILT configurations. The primary focus of attention is the suppression of in-plane rotor yoke loads for pitch manoeuvres in airplane mode; without suppression these loads would result in a very high level of fatigue damage. Multi-variable control law design methods are used to develop controller schemes and load suppression of 80-90% is demonstrated using rotor cyclic control, albeit at a 20-30% performance penalty. However, rotor flapping transients tend to increase by the action of the SLA system. A dual-objective control design approach demonstrates the effectiveness of suppressing both loads and flapping simultaneously.

A Sensor-Driven Approach to Distributed Shop Floor Planning and Control

2003 ◽  
Author(s):  
Lihui Wang ◽  
Weiming Shen ◽  
Xiaoqian Li ◽  
Sherman Lang
Keyword(s):  
Shop Floor ◽  
Seamless Integration ◽  
Intelligent Sensor ◽  
Planning And Control ◽  
Intelligent Sensors ◽  
System A ◽  
Floor Planning ◽  
High Level ◽  
And Control ◽  
Made In

The objective of this research is to develop methodology and framework for distributed shop floor planning, real-time monitoring, and remote device control supported by intelligent sensors. An intelligent sensor serves runtime data from bottom up to facilitate high-level decision-making. It assures that correct decisions are made in a timely manner, if compared with the best estimations of engineers. Being an adaptive system, a so-designed framework will improve the flexibility and dynamism of shop floor operations, and provide a seamless integration among process planning, resource scheduling, job execution, process monitoring, and device control. This paper presents principles of the methodology, details in architecture design, module interactions, information flow, and a proof-of-concept prototype implementation.

Non-Communicable Diseases and Global Health Politics

2019 ◽  
pp. 626-659
Author(s):  
Roger Magnusson
Keyword(s):  
Respiratory Diseases ◽  
Communicable Diseases ◽  
World Health ◽  
Global Response ◽  
Non Communicable Diseases ◽  
Health Politics ◽  
Chronic Respiratory Diseases ◽  
Health Organization ◽  
High Level ◽  
And Control

Non-communicable diseases (NCDs), including cardiovascular disease, cancer, chronic respiratory diseases, and diabetes, are responsible for around 70 percent of global deaths each year. This chapter describes how NCDs have become prevalent and critically evaluates global efforts to address NCDs and their risk factors, with a particular focus on the World Health Organization (WHO) and United Nations (UN) system. It explores the factors that have prevented those addressing NCDs from achieving access to resources and a priority commensurate with their impact on people’s lives. The chapter evaluates the global response to NCDs both prior to and since the UN High-Level Meeting on Prevention and Control of Non-communicable Diseases, held in 2011, and considers opportunities for strengthening that response in future.

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 Boundaryless working hours and recovery in Germany

2021 ◽  
Author(s):  
Laura Vieten ◽  
Anne Marit Wöhrmann ◽  
Alexandra Michel
Keyword(s):  
Working Hours ◽  
Working Time ◽  
Overtime Work ◽  
Psychological Detachment ◽  
Representative Study ◽  
Flexible Working ◽  
Recovery Experiences ◽  
High Level ◽  
And Control ◽  
Extended Work

Abstract Objective Due to recent trends such as globalization and digitalization, more and more employees tend to have flexible working time arrangements, including boundaryless working hours. The aim of this study was to investigate the relationships of various aspects of boundaryless working hours (overtime, Sunday work, and extended work availability) with employees’ state of recovery. Besides, we examined the mediating and moderating role of recovery experiences (psychological detachment, relaxation, mastery, and control) in these relationships. Methods We used data from 8586 employees (48% women; average age of 48 years) who took part in the 2017 BAuA-Working Time Survey, a representative study of the German working population. Regression analyses were conducted to test main effects as well as mediation and moderation. Results Overtime work, Sunday work, and extended work availability were negatively related to state of recovery. Psychological detachment mediated these relationships. Furthermore, we found that relaxation and control mediated the association between extended work availability and state of recovery. However, no relevant moderating effects were found. Conclusions Altogether, our findings indicate that various aspects of boundaryless working hours pose a risk to employees’ state of recovery and that especially psychological detachment is a potential mechanism in these relationships. In addition, the results suggest that a high level of recovery experiences cannot attenuate these negative relationships in leisure time. Therefore, employers and employees alike should try to avoid or minimize boundaryless working hours.

scholarly journals Molecular epidemiology of coxsackievirus A16 circulating in children in Beijing, China from 2010 to 2019

2021 ◽  
Author(s):  
Ya-Fang Hu ◽  
Li-Ping Jia ◽  
Fang-Yuan Yu ◽  
Li-Ying Liu ◽  
Qin-Wei Song ◽  
...  
Keyword(s):  
Molecular Epidemiology ◽  
Evolutionary Rate ◽  
Foot And Mouth Disease ◽  
Recent Common Ancestor ◽  
Rt Pcr ◽  
Coxsackievirus A16 ◽  
Most Recent Common Ancestor ◽  
Etiological Agents ◽  
High Level ◽  
And Control

Abstract Background Coxsackievirus A16 (CVA16) is one of the major etiological agents of hand, foot and mouth disease (HFMD). This study aimed to investigate the molecular epidemiology and evolutionary characteristics of CVA16. Methods Throat swabs were collected from children with HFMD and suspected HFMD during 2010–2019. Enteroviruses (EVs) were detected and typed by real-time reverse transcription-polymerase chain reaction (RT-PCR) and RT-PCR. The genotype, evolutionary rate, the most recent common ancestor, population dynamics and selection pressure of CVA16 were analyzed based on viral protein gene (VP1) by bioinformatics software. Results A total of 4709 throat swabs were screened. EVs were detected in 3180 samples and 814 were CVA16 positive. More than 81% of CVA16-positive children were under 5 years old. The prevalence of CVA16 showed obvious periodic fluctuations with a high level during 2010–2012 followed by an apparent decline during 2013–2017. However, the activities of CVA16 increased gradually during 2018–2019. All the Beijing CVA16 strains belonged to sub-genotype B1, and B1b was the dominant strain. One B1c strain was detected in Beijing for the first time in 2016. The estimated mean evolutionary rate of VP1 gene was 4.49 × 10–3 substitution/site/year. Methionine gradually fixed at site-23 of VP1 since 2012. Two sites were detected under episodic positive selection, one of which (site-223) located in neutralizing linear epitope PEP71. Conclusions The dominant strains of CVA16 belonged to clade B1b and evolved in a fast evolutionary rate during 2010–2019 in Beijing. To provide more favorable data for HFMD prevention and control, it is necessary to keep attention on molecular epidemiological and evolutionary characteristics of CVA16.

V64 The Phorbas system – a new single incision adjustable male sling: Implantation technique and first results

2014 ◽  
Vol 13 (1) ◽  
pp. eV64 ◽  
Author(s):  
R.M. Bauer ◽  
S. Herschorn ◽  
T.B. Olmedo ◽  
O.D. Reyes ◽  
W. Huebner
Keyword(s):  
Single Incision ◽  
Implantation Technique ◽  
Male Sling ◽  
System A ◽  
First Results

scholarly journals Effect of Ionizing Radiation on the Bacterial and Fungal Endophytes of the Halophytic Plant Kalidium schrenkianum

2021 ◽  
Vol 9 (5) ◽  
pp. 1050
Author(s):  
Jing Zhu ◽  
Xiang Sun ◽  
Zhi-Dong Zhang ◽  
Qi-Yong Tang ◽  
Mei-Ying Gu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Ionizing Radiation ◽  
Endophytic Bacteria ◽  
Fungal Endophytes ◽  
Root Endophytes ◽  
Fungal Community Structure ◽  
Geochemical Factors ◽  
Bacteria And Fungi ◽  
High Level ◽  
And Control

Endophytic bacteria and fungi colonize plants that grow in various types of terrestrial and aquatic ecosystems. Our study investigates the communities of endophytic bacteria and fungi of halophyte Kalidium schrenkianum growing in stressed habitats with ionizing radiation. The geochemical factors and radiation (at low, medium, high level and control) both affected the structure of endophytic communities. The bacterial class Actinobacteria and the fungal class Dothideomycetes predominated the endophytic communities of K. schrenkianum. Aerial tissues of K. schrenkianum had higher fungal diversity, while roots had higher bacterial diversity. Radiation had no significant effect on the abundance of bacterial classes. Soil pH, total nitrogen, and organic matter showed significant effects on the diversity of root endophytes. Radiation affected bacterial and fungal community structure in roots but not in aerial tissues, and had a strong effect on fungal co-occurrence networks. Overall, the genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments, however negative correlations were found between endophytic bacteria and fungi in the plant. The genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments. Our findings suggest that radiation affects root endophytes, and that the endophytes associated with aerial tissues and roots of K. schrenkianum follow different mechanisms for community assembly and different paradigms in stress response.

scholarly journals Does Gamifying Homework Influence Performance and Perceived Gameful Experience?

2021 ◽  
Vol 13 (9) ◽  
pp. 4829
Author(s):  
Ahmed Hosny Saleh Metwally ◽  
Maiga Chang ◽  
Yining Wang ◽  
Ahmed Mohamed Fahmy Yousef
Keyword(s):  
Learning Analytics ◽  
Educational Settings ◽  
Control Groups ◽  
Level Of Satisfaction ◽  
Growing Body ◽  
High Level ◽  
And Control

There is a growing body of literature that recognizes the importance of applying gamification in educational settings. This research developed an application to gamify students’ homework to address the concern of the students’ inability to complete their homework. This research aims to investigate students’ performance in doing their homework, and reflections and perceptions of the gameful experience in gamified homework exercises. Based on the data gathered from experimental and control groups (N = 84) via learning analytics, survey, and interview, the results show a high level of satisfaction according to students’ feedback. The most noticeable finding to extract from the analysis is that students can take on a persona, earn points, and experience a deeper sense of achievement through doing the gamified homework. Moreover, the students, on the whole, are likely to be intrinsically motivated whenever the homework is attributed to factors under their own control, when they consider that they have the expertise to be successful learners to achieve their desired objectives, and when they are interested in dealing with the homework for learning, not just achieving high grades.

Modeling human-like longitudinal driver model for intelligent vehicles based on reinforcement learning

2021 ◽  
pp. 095440702098357
Author(s):  
Ju Xie ◽  
Xing Xu ◽  
Feng Wang ◽  
Haobin Jiang
Keyword(s):  
Reinforcement Learning ◽  
Comprehensive Evaluation ◽  
Path Following ◽  
Intelligent Vehicles ◽  
Driver Model ◽  
Control Center ◽  
Training Performance ◽  
Learning Agents ◽  
System A ◽  
And Control

The driver model is the decision-making and control center of intelligent vehicle. In order to improve the adaptability of intelligent vehicles under complex driving conditions, and simulate the manipulation characteristics of the skilled driver under the driver-vehicle-road closed-loop system, a kind of human-like longitudinal driver model for intelligent vehicles based on reinforcement learning is proposed. This paper builds the lateral driver model for intelligent vehicles based on optimal preview control theory. Then, the control correction link of longitudinal driver model is established to calculate the throttle opening or brake pedal travel for the desired longitudinal acceleration. Moreover, the reinforcement learning agents for longitudinal driver model is parallel trained by comprehensive evaluation index and skilled driver data. Lastly, training performance and scenarios verification between the simulation experiment and the real car test are performed to verify the effectiveness of the reinforcement learning based longitudinal driver model. The results show that the proposed human-like longitudinal driver model based on reinforcement learning can help intelligent vehicles effectively imitate the speed control behavior of the skilled driver in various path-following scenarios.

scholarly journals Biotech/GM crops in horticulture: plum cv. HoneySweet resistant to Plum pox virus

2012 ◽  
Vol 48 (Special Issue) ◽  
pp. S43-S48 ◽  
Author(s):  
J. Polák ◽  
J. Kumar ◽  
B. Krška ◽  
M. Ravelonandro
Keyword(s):  
Tree Breeding ◽  
Fruit Tree ◽  
Eating Quality ◽  
Plum Pox Virus ◽  
Infection Pressure ◽  
Public Sector Research ◽  
The Usa ◽  
Chlorotic Leaf ◽  
High Level ◽  
And Control

Commercialisation of Biotech/GM (Biotech) crops started in 1995. Not only field crops, but also horticultural transgenic crops are under development and are beginning to be commercialised. Genetic engineering has the potential to revolutionise fruit tree breeding. The development of transgenic fruit cultivars is in progress. Over the past 20 years an international public sector research team has collaborated in the development of HoneySweet plum which is highly resistant to Plum pox virus (PPV) the most devastating disease of plums and other stone fruits. HoneySweet was deregulated in the USA in 2010. HoneySweet (aka C5) has been evaluated for eleven years (2002–2012) in a regulated field trial in the CzechRepublic for the resistance to PPV, Prune dwarf virus (PDV), and Apple chlorotic leaf spot virus (ACLSV), all of them being serious diseases of plum. Even under the high and permanent infection pressure produced through grafting, PPV has only been detected in HoneySweet trees in several leaves and fruits situated close to the point of inoculum grafting. The lack of infection spread in HoneySweet demonstrates its high level of PPV resistance. Co-infections of PPV with PDV and/or ACLSV had practically no influence on the quantity and quality of HoneySweet fruit which are large, sweet, and of a high eating quality. In many respects, they are superior to the fruits of the well-known cultivar Stanley. Many fruit growers and fruit tree nurseries in the CzechRepublic are supportive of the deregulation of HoneySweet plum to help improve the plum production and control the spread of PPV.

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