Marc Stelzner

Accelerated join evaluation in Semantic Web databases by using FPGAs

While the amount of information steadily increases, the requirements on the response time to query these information become more strict. Under those conditions, conventional database systems reach their limits and cannot meet these performance requirements anymore. In recent years, systems with many processing cores are considered to satisfy these demands. Furthermore, these systems include more and more heterogeneous cores tailor‐made to solve one specific task in an efficient manner. However, dedicated hardware accelerators are inflexible and cannot be adapted to the requirements of a dedicated query. Thus, the challenge is orchestrating the diversity of the functionality of all the cores to be optimized for performance/energy efficiency. In this paper, a concept is introduced on how to develop a flexible Field‐Programmable Gate Arrays (FPGA)‐based hardware accelerator to improve the performance of query evaluation in a Semantic Web database. As a first step to the hardware/software system, several joint algorithms are implemented on an FPGA and evaluated against a well‐developed software solution (implemented in C). The comparison shows a significant speedup of up to 10 times. Because of the complexity of the join operator, it is promising that the overall performance of query evaluation can be further enhanced by processing whole queries on an FPGA. Copyright

Function Centric Networking: an Approach for Addressing in In-Body Nano Networks

We are looking at the combination of in-body nano communication with the Internet of Things (IoT) -- especially Body Area Networks (BAN) -- and the resulting research challenges in the Internet of Nano Things (IoNT). Moreover, our concept for Function Centric Networking presents an approach to deal with these challenges by addressing specific groups of interchangeable and replaceable nano machines.

Hybrid FPGA approach for a B + tree in a Semantic Web database system

In this paper we present a hybrid index structure which is allocated in a Field Programmable Gate Array (FPGA) and a traditional CPU-based host system. The used index structure of this system is a B+-tree which is a common index used in disk based databases. The hybrid index is divided into two parts. The lower levels of the B+-tree, especially the leaves where the values are stored, are located on the host system while the root and the most upper levels with the interior nodes are stored on the FPGA. We speed up the search in the upper levels of our hybrid index by applying an FPGA accelerated parallel search. In the evaluation we show how the amount of keys inside the interior nodes on the FPGA and the order of the B+-tree take an impact on the whole hybrid system. The results show that the computation time of the software system can be halved.

Parallel and Pipelined Filter Operator for Hardware-Accelerated Operator Graphs in Semantic Web Databases

In this paper, we investigate the use of Field Programmable Gate Arrays (FPGAs) to enhance the performance of filter expressions in Semantic Web databases. The filter operator is a central part of query evaluation. Its main objective is to reduce the amount of data as early as possible in order to reduce the calculation costs for succeeding and more complex operators such as join operators. Due to the proximity to the data source it is essential for the overall query performance that the filter operator is able to evaluate single data items as fast as possible. In this work, the advantages of using FPGAs in query evaluation are outlined and an overview about the provided degree of parallelism is given. We propose two different approaches to implement the filter operator for the Semantic Web database LUPOSDATE. The Fully-Parallel Filter evaluates all conditions by dividing the input into several sub-items which are evaluated by dedicated sub-filters in parallel. The second approach creates a pipeline of sub-filters to evaluate the filter expression step-by-step. If an item reaches the end of this pipeline then it complies the whole filter expression. The final evaluation shows that both approaches of the hardware-implemented filter operator defeat the comparable software solution written in C running at 2.66 GHz. Processing 100M items per second, the hardware-accelerated filter running at 200 MHz provides a more than 5 times higher throughput than the general-purpose CPU. In contrast to the software solution, the total throughput is independent of the match rate and the structure of the filter expression, and is a valuable contribution to the hardware-accelerated query evaluation.

A Formal Definition for Nanorobots and Nanonetworks

Nano computation and communication research examines minuscule devices like sensor nodes or robots. Over the last decade, it has attracted attention from many different perspectives, including material sciences, biomedical engineering, and algorithm design. With growing maturity and diversity, a common terminology is increasingly important.

BloodVoyagerS: simulation of the work environment of medical nanobots

The simulation of nanobots in their working environment is crucial to promote their application in the medical context. Several simulators for nanonetworks investigate new communication paradigms at nanoscale. However, the influence of the environment, namely the human body, on the movement and communication of nanobots was rarely considered so far. We propose a framework for simulating medical nanonetworks, which integrates a nanonetwork simulator with a body simulator. We derive requirements for a body model that forms the basis for our prototypical implementation of the body simulator BloodVoyagerS as part of the network simulator ns-3. Our evaluation shows that BloodVoyagerS successfully moves nanobots in the simulated cardiovascular system. After about 7 minutes, the nanobot distribution reaches a dynamic equilibrium. The prototype shows promise to provide a more realistic full-body simulation to investigate movement and communication of nanobots in medical applications.

Nanoscale diagnostic procedures: sensing inside the human body

The application of nanotechnology in medicine is envisioned for detecting and treating diseases. In literature, the ability of nanode-vices to sense their environment is often taken for granted and precondition for application scenarios. However, how this is done and which diagnostic procedures actually benefit from properly qualified nanodevices is rarely stated. In this paper, we distinguish four traditional diagnostic procedures and introduce our evaluation of how nanonodes may profit from quantitative procedures.

In-body nanonetwork routing based on MANET and THz

Devices at the nanoscale are envisioned to be used in medical applications to detect and treat diseases within a human body. However, due to its severe resource constraints, a nanoscale device might not execute complex tasks on its own. For this, we envision a medical nanonetwork, comprising an in-body network built of nanonodes and a Body Area Network (BAN) built of macroscale devices coordinating and controlling the nanonodes. Due to the characteristics of the in-body network and its nodes, conventional routing protocols for macroscale mobile ad-hoc networks (MANET) are not directly applicable and novel approaches are needed. However, since a nanonetwork shares some characteristics of macroscale MANETs, we identified promising protocols and evaluated their suitability for nanonetworks using THz communication. We define requirements for their applicability and compare their performance.

Function Centric Nano-Networking: Addressing nano machines in a medical application scenario

Abstract We discuss the combination of in-body nano communication with the Internet of Things (IoT) as the Internet of Nano Things (IoNT). This combination enables a wide range of new applications and opportunities – particularly in the biomedical domain – but it also entails a number of new challenges. One of many research challenges in functional and non-functional aspects is the addressing and naming of nodes in a nano network. Our study in this area not only includes traditional techniques driven from today’s IoT, but also new unconventional ideas, originating from molecular level communication. We come up with a summary of either theoretical, simulated or realized ideas to draw conclusions about implementations and performance potential, with a focus on medical in-body communication scenarios, before we present our concept, Function Centric Nano-Networking (FCNN). FCNN allows us to address groups of interchangeable nano machines in a network by using location information and functional capabilities of the machines. This concept does not rely on the durability and uniqueness of individual nodes. We are comparing the novel concept of FCNN with similar ones and highlight elementary differences between them as well advantages and disadvantages.