David Edward Robillard

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This paper presents VelocityOLAP (VOLAP), a distributed real-time OLAP system for high velocity data. VOLAP makes use of dimension hierarchies, is highly scalable, and exploits both multi-core and multi-processor parallelism. In contrast to other high performance OLAP systems such as SAP HANA or IBM Netezza that rely on vertical scaling or special purpose(More)
Fast aggregation of data with many dimensions is a key component of many applications. The R-tree is the traditional data structure for indexing multi-dimensional data, but even the best R-tree variants suffer from performance degradation as the number of dimensions increases. The DC-tree addressed this issue by replacing Minimum Bounding Rectangle (MBR)(More)
MOTIVATION Interactions between amino acids are important determinants of the structure, stability and function of proteins. Several tools have been developed for the identification and analysis of such interactions in proteins based on the extensive studies carried out on high-resolution structures from Protein Data Bank (PDB). Although these tools allow(More)
This thesis introduces PEMS2, an improvement to PEMS (Parallel External Memory System). PEMS executes Bulk-Synchronous Parallel (BSP) algorithms in an External Memory (EM) context, enabling computation with very large data sets which exceed the size of main memory. Many parallel algorithms have been designed and implemented for Bulk-Synchronous Parallel(More)
With the advent of inexpensive cloud computing resources, scalable distributed data stores have surged in popularity [7, 10, 16, 17, 20]. Such systems focus on horizontal scalability and take advantage of cheap, pay by the hour, compute nodes provisioned through the cloud [6]. In doing so, these systems are able to distribute query and insert load across(More)
This paper presents an adaptable steganography (information hiding) method for digital radio communication. Many radio steganography methods exist, but most are defined at higher levels of the protocol stack and are thus protocol dependent. In contrast, this method is defined at the physical layer, which makes it widely applicable regardless of the(More)
This paper presents VelocityOLAP (VOLAP), a distributed real-time OLAP system for high-velocity data. VOLAP makes use of dimension hierarchies, is highly scalable, exploits both multi-core and multi-processor parallelism, and can guarantee serializable execution of insert and query operations. In contrast to other high performance OLAP systems such as SAP(More)
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