Pedro Vieira

Adaptive workflow management in WorkSCo

Workflow technology has been typically used to automate well defined and repetitive business processes. The application of workflow systems to non-traditional, and more flexible environments has been a main topic of interest among the workflow research community. Two different approaches emerged in this regard, namely dynamic evolution and open point based adaptation. The former enables the modification of workflows even during the execution of workflow instances. The later supports the loose modeling of workflows, postponing the complete specification to runtime. In this paper, we present a workflow system that provides full flexibility by combining these two approaches.

Dynamic evolution in workflow management systems

The environments where workflow management systems are typically used in are constantly changing. It is nearly impossible to foresee, at business process design stage, all the combinations of tasks needed to achieve the process goals. Workflow management systems capable of supporting dynamic changes on executing instances in a flexible manner are thereby demanded. Former approaches have proposed a solution to this issue based on workflow type versioning and workflow instance migration. However, the operations that handle the modification of workflow types as well as the migration algorithm for workflow instances are tied to a particular representation of workflow types. This means that whenever the representation changes, the migration algorithms and the modification operations have to change accordingly. This is a current problem due to the uprising of different specifications for workflow definition languages, which are far away from stabilizing. In this paper, we address this problem by clearly decoupling the modification operations of workflow types from the internal structures and algorithms responsible for the instances migration. In this manner we enable the use of different workflow definition languages while keeping the same internal structures and migration algorithms.

Improving accuracy for OTD based 3G geolocation in real urban/suburban environments

This paper presents the recent research results about the development of a Observed Time Difference (OTD) based geolocation algorithm based on network trace data, for a real Universal Mobile Telecommunication System (UMTS) Network. The initial results have been published in [1], the current paper focus on increasing the sample convergence rate, and introducing a new filtering approach based on a moving average spatial filter, to increase accuracy. Field tests have been carried out for two radio environments (urban and suburban) in the Lisbon area, Portugal. The new enhancements produced a geopositioning success rate of 47% and 31%, and a median accuracy of 151 m and 337 m, for the urban and suburban environments, respectively. The implemented filter produced a 16% and 20% increase on accuracy, when compared with the geopositioned raw data. The obtained results are rather promising in accuracy and geolocation success rate. OTD positioning smoothed by moving average spatial filtering reveals a strong approach for positioning trace extracted events, vital for boosting Self-Organizing Networks (SON) over a 3G network.

Wavelet analysis of the autonomic outflowof the pupil's variation in normal subjects, given stimuli

This paper presents preliminary results of Wavelet analysis of the pupil size variation signal. A Pupillometer has been developed in order to detect the pupils variation in time in a non-invasive way. The output signal of the equipment expresses the pupils features variation in time (area, perimeter, vertical diameter, horizontal diameter). We know that the Autonomic Nervous System (ANS) is divided into the Sympathetic and Parasympathetic components and theoretically they are always competing with each other as a two oscillator model. The aim of this project is to identify these components and their frequency bands. With the present results we show that the signal from the pupils variation has two major frequency bands, the first being the 0–1 Hz band (LF — Low Frequency) and the second being 1–2Hz band (HF — High Frequency). From the literature we know that the Sympathetic Nervous System (SNS) behaves in a lower frequency than the Parasympathetic (PSNS) one. This means that SNS oscillates in the LF band and PSNS oscillates in the HF band.

The influence of wearing a wallet in your sitting posture — A quantitative study using an intelligent chair

Wearing an object in the rear pocket alters the interface between the body and the chair, leading to the compression of the sciatic nerve. Prolonged sitting behaviors with such objects can lead to a health disorder called Piriformis Syndrome. In this paper, we use an intelligent office chair in order to detect the wallet usage as a “bad sitting posture”, as sitting on a wallet can create an uneven sitting surface, subsequently tilting the pelvis in the frontal plane. The system is comprised of a pneumatic circuit and is able to detect and classify, based on Artificial Neural Network, 12 standardized sitting postures, with an accuracy of 80.9%. In this test, we asked 36 subjects (24 males-M and 12 females-F) to wear a wallet in the back pocket in 12 testing levels, based on 3 wallets sizes (small, medium and large) and 4 levels of wallet heights (no paper cards, 8 cards, 16 cards and 24 cards). We detected the usage of wallets as an incorrect posture in 58.8% for all levels (61.1% for Male and 54.2% for Female). We observed that the size of the wallet did not alter results significantly (60.4% for smaller area versus 57.6% in the larger area), while the wallet height had a large influence (46.2% for no cards versus 71.3% for 24 cards). We also tested wallet usage in the front pocket with an average of 16.7%, showing that this usage doesnt alter significantly the sitting posture. This work shows that the creation of an alert protocol for the wallet usage is possible to be implemented in our intelligent chair system.

Animated maps for analysis of personal performance in games

In recent years, the e-sports (electronic sports) phenomenon has been a growing trend and, with it, the interest in online videogames by players and spectators has also risen. One of the most popular genre of games is the MOBA (Multiplayer Online Battle Arena). Similarly to traditional sports, during a match there are several types of events that are of interest to players, coaches and analysts. These events can range from the position of a player at a particular moment, to game specific events, such as the position where a player died or the number of bullets fired in a certain zone. With the advancements in technology, it has become increasingly simpler to utilize telemetry techniques to collect data regarding the events that take place during a match. To analyze these data effectively and efficiently, it is necessary to explore which visualization techniques are better suited to the available data and the requirements of users. Regarding spatio-temporal data, the literature shows that although there are multiple visualization techniques available, the video game industry does not take full advantage of their potential. This article presents a prototype that explores several visualization techniques, namely animated maps, with the purpose of understanding their adequacy to display this type of information, while at the same time creating a tool for player performance analysis that satisfies the needs and expectations of users.

A Novel Method of Measuring Autonomic Nervous System Pupil Dynamics Using Wavelet Analysis

This paper presents a Pupillometer that has been developed in order to detect the pupil’s variation in time in a non-invasive way. The output signal of the equipment, a Pupillogram, was analyzed using Time-Frequency Analysis with the aim of better understanding the brain signals’ activity expressed in the human eye.

Development of an instrument to measure pupil dynamics in subjects suffering from Neuro-Ophthalmologic disorders

The pupil moves in response to the variation in light intensity in th e retina, with a view to assisting the optimizing of visual perception. In dim light, pupil dilation (midriasis) is an effective way to maximize the number of photons reaching the retina, which in turn activates adaptive mechanisms to low light intensity. When exposed to bright light, miosis causes an adequate reduction in the intensity of light in the retina, acting as immediate response to the mechanisms of adapting to intense light.