Ontology analysis has been shown to be an effective first step in the construction of robust knowledge based system. Moreover, the popularity of semantic technologies and the semantic web has provided several beneficial opportunities for the modeling and computer security communities of interest. This paper describes the role of ontologies in facilitating network security modeling. It outlines the technical challenges in distributed network security simulation modeling and describes how ontology-based methods may be applied to address these challenges. The paper concludes by describing an ontology-based solution framework for network security simulation modeling and analysis and outlining the benefits of this solution approach.

High packet network have become an essential in modern multimedia communication. Shared buffer is commonly used to utilize the buffer in the switch. In this paper, we analyse the performance of shared buffer with different memory sizes. The architecture of the multi-class shared buffer is developed for 16x16 ports switch that is targeted in Xilinx FPGA. The performance of the multi-class shared buffer switch is analysed in term of throughput and mean delay. Based on the simulation with different memory sizes, it is observed that the optimum selection of memory size under uniform traffic depends on the maximum traffic load of the switch.

The incidence of pancreatic ascites is unusual. It is uncommon sequelae of chronic pancreatitis. Smith first discovered it in 1953 in the literature. The etiology includes chronic pancreatitis, pancreatic pseudocyst, pancreatic trauma and idiopathic in origin. Despite a rise in the incidence, it is scarcely reported. This is a case of a 20-year-old man presented with repeated acute pancreatitis episode complicated with gross ascites. Pancreatic duct stones were identified intra-operatively. Frey's surgery was the procedure of choice. We discuss the presentation, choice of treatment and outcome.

Radiofrequency ablation (RFA) has evolved to become the treatment of choice for non-resectable recurrent colorectal liver metastasis. It is however, not without complications. Portal vein thrombosis following RFA is rare but can be fatal to the outcome of the patient. Here, we present a case of a 66-year-old man who developed portal vein thrombosis following RFA. CT scan revealed a left portal vein thrombosis. This case report highlights the challenges and multimodal treatment of portal vein thrombosis following Radiofrequency ablation (RFA) in a cirrhotic patient.

A 20-year-old man presented with peritonitis requiring emergency laparotomy. He was found to have a huge liver abscess on the right lobe. Open drainage was performed but the abscess was persistently unresolved upon follow up. Computed tomography (CT) revealed a solid liver lesion with raised Ca 19-9. Right hepatectomy was subjected and histology was consistent with a rare and aggressive case of embryonal sarcoma of the liver. Despite oncologic resection, he developed local recurrence and succumbed to death in 6 month postoperatively. We describe a unique aetiology of liver abscess with literature reviews of undifferentiated embryonal sarcoma of the liver.