Design of digital controllers for uncertain chaotic systems using fuzzy logic

A new and systematic method to design digital controllers for uncertain chaotic systems with structured uncertainties is presented in this paper. Takagi-Sugeno (TS) fuzzy model is used to model the chaotic dynamic system, while the uncertainties are decomposed such that the uncertain chaotic system can be rewritten as a set of local linear models with an additional disturbed input. Conventional control techniques are utilized to develop the continuous-time controllers first. Then, the digital controllers are obtained as the digital redesign of the continuous-time controllers using the state-matching approach. The performance of the proposed controller design is illustrated through numerical examples.     

Gradual refinement for application-specific MPSoC design from Simulink model to RTL implementation

The application-specific multiprocessor system-on-chip （MPSoC） architecture is becoming an attractive solution to deal with increasingly complex embedded applications, which require both high performance and flexible programmability. As an effective method for MPSoC development, we present a gradual refinement flow starting from a high-level Simulink model to a synthesizable and executable hardware and software specification. The proposed methodology consists of five different abstract levels： Simulink combined algorithm and architecture model （CAAM）, virtual architecture （VA）, transactional accurate architecture （TA）, virtual prototype （VP） and field-programmable gate array （FPGA） emulation. Experimental results of Motion-JPEG and H.264 show that the proposed gradual refinement flow can generate various MPSoC architectures from an original Simulink model, allowing processor, communication and tasks design space exploration.     

The Muslim football player and Ramadan: current challenges

Islam is a monotheistic Abrahamic faith characterised by devotional orthopraxy. The actions expected of followers of Islam are closely prescribed in the Qur'an. Muslims understand Ramadan as a mandatory requirement, excused only in the event of illness, infirmity or extremes of age. Due to the increasing popularity of football among Muslims, more and more Muslim football players of all levels make the decision to follow the Ramadan fast while they need to practise and compete. Sports medicine clinicians and scientists have the responsibility to provide them with the knowledge and evidence on how exactly Ramadan fasting impacts on their performance and how to optimise their eating, drinking and sleeping in order to minimise negative effects of their religious practice, should any have been demonstrated. The first International Federation of Football Associations (FIFA) Medical Assessment and Research Centre (F-MARC) study concluded that biochemical, nutritional, subjective well-being and performance variables were not adversely affected in young male national level players who followed Ramadan fasting in a controlled environment. Match performance was however not measured and the study did not include elite level players, leading to the Ramadan consensus meeting in order to answer the remaining questions. The conclusions and recommendations published in this supplement suggest that the best coping strategies will remain individual - as is the choice to fast.     

Finite/fixed-time synchronization control of coupled memristive neural networks

Finite-time and fixed-time synchronization (FAFS) of coupled memristive neural networks (CMNNs) with discontinuous feedback functions are explored in this paper. Firstly, a more comprehensive stability theory is systematically established. Secondly, by designing adaptive feedback controller and discontinuous feedback controller, both finite-time and fixed-time synchronization can be realized through regulating the main control parameter. Thirdly, 1-norm and quadratic-norm Lyapunov functions are considered simultaneously in this article, while in estimating the settling time, the former one is more accurate than the latter one under the same synchronization criteria. Finally, in numerical simulation, the analysis and comparison of the proposed controllers are given to show the effectiveness of the corresponding results.     

Diagnostic coding of abuse related fractures at two children's emergency departments

Objectives

Pediatric fractures suspicious for abuse are often evaluated in emergency departments (ED), although corresponding diagnostic coding for possible abuse may be lacking. Thus, the primary objective of this study was to determine the proportion of fracture cases investigated in the ED for abuse that had corresponding International Classification of Diseases (ICD) codes documenting abuse suspicion. Additional objectives were to determine the proportion of these fractures with admission ICD abuse coding, and physician text diagnoses recording abuse suspicion in the ED and/or admission notes. Factors possibly associated with abuse-related ED ICD codes were also examined.

Methods

Children less than three years of age that presented primarily with a fracture to two large academic children's hospitals from 1997 to 2007 and were evaluated for suspicion of abuse by child protective services were included in this retrospective review. The main outcome measure was the proportion of the fracture cases that had abuse suspicion reflected in ED discharge ICD codes.

Results

Of the 216 eligible patients, only 23 (11.5%) patients had ED ICD codes that included the possibility of abuse. Forty-nine (22.7%) had the possibility for abuse documented by physicians as an ED discharge diagnosis. In addition, 53/149 (35.6%) of all admitted patients and 34/55 (61.8%) of confirmed abuse cases included abuse-related admission ICD coding. Female gender was found to be a factor associated with ED ICD abuse codes.

Conclusion

Current standards of ICD coding result in a significant underestimate of the prevalence of children assessed in the ED and hospital wards for possible and confirmed abusive fracture(s).     

Modified particle swarm optimization for optimum design of spread footing and retaining wall

This paper deals with the economically optimized design and sensitivity of two of the most widely used systems in geotechnical engineering: spread footing and retaining wall. Several recent advanced optimization methods have been developed, but very few of these methods have been applied to geotechnical problems. The current research develops a modified particle swarm optimization (MPSO) approach to obtain the optimum design of spread footing and retaining wall. The algorithm handles the problem-specific constraints using a penalty function approach. The optimization procedure controls all geotechnical and structural design constraints while reducing the overall cost of the structures. To verify the effectiveness and robustness of the proposed algorithm, three case studies of spread footing and retaining wall are illustrated. Comparison of the results of the present method, standard PSO, and other selected methods employed in previous studies shows the reliability and accuracy of the algorithm. Moreover, the parametric performance is investigated in order to examine the effect of relevant variables on the optimum design of the footing and the retaining structure utilizing the proposed method.     

Psychology students’ perception of and engagement with feedback as a function of year of study

Undergraduate students’ perception of feedback and level of engagement with the feedback they receive have gained increasing attention in the educational literature recently to identify areas which require educators’ attention. However, research in this area has generally been based on limited self-selecting samples, and has not considered how students’ relationship with feedback may alter depending on their year of study. To address this, a survey measuring students’ views and practices regarding feedback was completed at a higher education institution by 447 first-, second- and third-year psychology students, representing 77% of the cohort. Findings revealed that third years responded more negatively in both areas than their first- and second-year counterparts, whose ratings on these aspects themselves were far from optimal. These findings highlight the need for early interventions to improve students’ perception of and engagement with feedback in the earlier years, and to prevent the recorded deterioration later on in the degree course.