We present a system for online monitoring of maritime activity over streaming positions from numerous vessels sailing at sea. It employs an online tracking module for detecting important changes in the evolving trajectory of each vessel across time, and thus can incrementally retain concise, yet reliable summaries of its recent movement. In addition, thanks to its complex event recognition module, this system can also offer instant notification to marine authorities regarding emergency situations, such as risk of collisions, suspicious moves in protected zones, or package picking at open sea. Not only did our extensive tests validate the performance, efficiency, and robustness of the system against scalable volumes of real-world and synthetically enlarged datasets, but its deployment against online feeds from vessels has also confirmed its capabilities for effective, real-time maritime surveillance.

The concept of event processing is established as a generic computational paradigm in various application fields. Events report on state changes of a system and its environment. Complex Event Recognition (CER) refers to the identification of composite events of interest, which are collections of simple, derived events that satisfy some pattern, thereby providing the opportunity for reactive and proactive measures. Examples include the recognition of anomalies in maritime surveillance, electronic fraud, cardiac arrhythmias and epidemic spread. This survey elaborates on the whole pipeline from the time CER queries are expressed in the most prominent languages, to algorithmic toolkits for scaling-out CER to clustered and geo-distributed architectural settings. We also highlight future research directions.

Complex event recognition (CER) applications exhibit various types of uncertainty, ranging from incomplete and erroneous data streams to imperfect complex event patterns. We review CER techniques that handle, to some extent, uncertainty. We examine techniques based on automata, probabilistic graphical models, and first-order logic, which are the most common ones, and approaches based on Petri nets and grammars, which are less frequently used. Several limitations are identified with respect to the employed languages, their probabilistic models, and their performance, as compared to the purely deterministic cases. Based on those limitations, we highlight promising directions for future work.

BackgroundThe limited number of systematic, controlled studies that assess the safety and efficacy of psychotropic medications for children reinforce the hesitation and reluctance of parents to administer such medications. The aim of this study was to investigate the attitudes of parents of children with psychiatric disorders, towards psychotropic medication.MethodsA 20-item questionnaire was distributed to 140 parents during their first contact with an outpatient child psychiatric service. The questionnaire comprised of questions regarding the opinions, knowledge and attitudes of parents towards children's psychotropic medication. Sociodemographic data concerning parents and children were also recorded. Frequency tables were created and the chi-square test and Fisher's exact tests were used for the comparison of the participants' responses according to sex, educational level, age and gender of the child and use of medication.ResultsRespondents were mostly mothers aged 25–45 years. Children for whom they asked for help with were mostly boys, aged between 6 and 12 years old. A total of 83% of the subjects stated that they knew psychotropic drugs are classified into categories, each having a distinct mechanism of action and effectiveness. A total of 40% believe that there is a proper use of psychotropic medication, while 20% believe that psychiatrists unnecessarily use high doses of psychotropic medication. A total of 80% fear psychotropic agents more than other types of medication. Most parents are afraid to administer psychotropic medication to their child when compared to any other medication, and believe that psychotherapy is the most effective method of dealing with every kind of mental disorders, including childhood schizophrenia (65%). The belief that children who take psychotropic medication from early childhood are more likely to develop drug addiction later is correlated with the parental level of education.ConclusionParents' opinions and beliefs are not in line with scientific facts. This suggests a need to further inform the parents on the safety and efficacy of psychotropic medication in order to improve treatment compliance.