A Comparative Analysis of Process Instance Cluster Techniques

The application of process mining and analysis techniques to the process logs of information systems often leads to highly complex results, e.g. in terms of a high number of elements in the mined model. Thus, clustering corresponding log files is mandatory in the context of an expedient analysis. Against that background, many cluster techniques were developed during the last years but, at the same time, it is unclear how powerful they operate in particular application scenarios. Therefore, the paper at hand aims at analyzing and comparing the capabilities of existing cluster techniques with regard to different objectives. As a result, some techniques are more suitable for the handling of particular scenarios than others and there are also general challenges in their application, which should be addressed in future work

ONE OR TWO SCREWS IN THE FRACTURE OF THE ODONTOID PROCESS? EVALUATION USING COMPUTED TOMOGRAPHY

Objective:To evaluate the bone area of the odontoid process through computed tomography and its relation with the area of one and two screws in the male and female subjects.Methods:188 CT scans of adults were analyzed. The isthmus area was selected and the transverse diameter was measured at 1.2 mm from the base of odontoid.Results:After placement of a screw, the odontoid area remains with 82% of free bone for both men and women. With two screws, 45.6% of women, had a free bone area of the odontoid process between 50% and 75% and 54.4% were above 75%. 26.6% men had percentage from 50% to 75% of free bone area and 73.4% above 75% (p=0.07). After the placement of two screws, the bone area was, in average, 77.3% in men and 75.4% in women. Using the Student t-test, the differences between the average of percentage of free bone area in men and women are significantly lower in women (p=0.0012).Conclusion:The pre-operative planning through CT can help to choose the number of screws in the odontoid process. The choice should be particularly careful when using two screws in women