he demand for navigation systems is rapidly increasing, especially in GNSS-denied environments. The ubiquitous use of smart mobile devices equipped with various sensors encouraged many researchers to investigate their use in improving indoor navigation, where GNSS is not available. Inertia navigation sensors installed in mobile devices are normally low cost and drift significantly. Consequently, there is a need for auxiliary systems to aid the navigation process, which can be achieved using external sensors or additional information extracted from, for example, base maps. In this research paper, maps have been selected as a navigation aid. Previously, maps were used for navigation aiding through geospatial data models and map-matching algorithms. These methods are based on creating geospatial data models on the fly and integrating them in the navigation database, which makes them computationally expensive and time-consuming. In this research paper, the maps were used in an innovative way. The map directions were used in Pedestrian a dead reckoning (PDR) mode to improve the low-accuracy directions derived from portable device sensors. This method is significantly computationally efficient compared to traditional geospatial map-matching algorithms. The new approach replaces the traditional geospatial database with a list of street directions and paths that are used as Map Heading Constraints (MHC) when navigating (walking) in straight directions. The proposed technique was tested on trajectories in GNSS denied environment (underground parking) using an iphone6s smart-phone and compared with other solutions that used the portable device sensors only. The comparison showed a significant improvement in position accuracy (up to 90%) in comparison to using the portable device sensors only (no aiding).

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boys born with penopubic epispadias and 3 girls with incontinent epispadias, all had no prior surgery were operated via the sub symphyseal approach. Their age varied between 3 and 11 years. In boys the urethral plate was first dissected and lifted from the corporal bodies down to the glans penis distally and the wide bladder neck proximally i.e partial penile disassembly. In girls the skin wedge between the crura of the clitoral bodies was raised and tabularized to be used for retraction and further proximal dissection behind the pubic symphysis. The urethra was tubularized over 10 French catheter 10 French catheter, and the bladder neck was plicated over the catheter in 6 children using non absorbable sutures. In 3 children (one boy and 2 girls) the bladder neck was too wide, and a triangular wedge of tissue was excised followed by 2-layer closure with long lasting absorbable sutures around the catheter. The bladder was filled with saline and the water tightness of the suture line and/or the competence of the plicated bladder neck were tested. The corporal bodies are rotated and sutured together to correct the dorsal chordee and the penis is resurfaced by skin. In girls the crural bodies are approximated followed by monsplasty.RESULTS: The follow up ranged between 6 months and 5 years. All boys and 2 girls who were incontinent achieved dryness for 3þ hours and achieved volitional voiding over 6 months postoperatively. One girl exhibited stress incontinence which improved considerably following periurethral injection of bulking agent. The bladder capacity increased from 50-120 ml preoperatively to 150-230 ml. post-surgery with gradual increase of the bladder capacity over the years. 6/18 renal units showed vesicoureteral reflux (Grade II-III) prior to surgery and were all corrected successfully by endoscopic bulking agent injections.CONCLUSIONS: The sub symphyseal exposure to achieve continence by plicating and/or reconstructing the bladder neck provides a safe and effective surgical approach for children born with incontinent epispadias. Furthermore, in boys it can be combined with penile disassembly.