A framework for WWW query processing

This paper looks at the processing of skyline queries on peer-to-peer (P2P) networks. We propose Skyframe, a framework for efficient skyline query processing in P2P systems, which addresses the challenges of quick response time, low network communication cost and query load balancing among peers. Skyframe consists of two querying methods: one is optimized for network communication while the other focuses on query response time. These methods are different in the way in which the query search space is defined. In particular, the first method uses a high dominating point that has a large dominating region to prune the search space to achieve a low cost in network communication. On the other hand, the second method relaxes the search space in order to allow parallel query processing to speed up query response. Skyframe achieves query load balancing by both query load conscious data space splitting/merging during the join/departure of nodes and dynamic load migration. We further show how to apply Skyframe to both the P2P systems supporting multi-dimensional indexing and the P2P systems supporting single-dimensional indexing. Finally, we have conducted extensive experiments on both real and synthetic data sets over two existing P2P systems: CAN (Ratnasamy in A scalable content-addressable network. In: Proceedings of SIGCOMM Conference, pp. 161---172, 2001) and BATON (Jagadish et al. in A balanced tree structure for peer-to-peer networks. In: Proceedings of VLDB Conference, pp. 661---672, 2005) to evaluate the effectiveness and scalability of Skyframe.

The upcoming generation of computer hardware poses several new challenges for database developers and engineers. Software in general and database management systems (DBMSs) in particular will no longer benefit from performance gains of future hardware due to increase clock speed, as it was the case for the last 35 years; instead, the number of cores per CPU will increase steadily. Today’s approach is to run each query on a single core or only a few different cores using parallel query execution. This approach suffers from several problems (e.g. contention problem) and therefore leads to poor speed up and scale up behavior. These observations open several important research questions on how to use the new multi-core CPU architecture for improving the overall performance of DBMSs. This paper outlines our approach for query processing on multi-core CPU architectures. We present an abstract architecture view for multi-core CPUs, meta operators to control and to interact with the hardware, and a new query operator model that makes use of the meta operators to control the parallel execution of a query over different cores. We illustrate how each of these parts fits in our framework for query processing on multi-core architectures.

CPP: Towards comprehensive privacy preserving for query processing in information networks

The pervasiveness of GPS-enabled devices and wireless communication technologies results in massive trajectory data, incurring expensive cost for storage, transmission, and query processing. To relieve this problem, in this paper we propose a novel framework for compressing trajectory data, REST ( Re ference-based S patio- t emporal trajectory compression), by which a raw trajectory is represented by concatenation of a series of historical (sub-)trajectories (called reference trajectories) that form the compressed trajectory within a given spatio-temporal deviation threshold. In order to construct a reference trajectory set that can most benefit the subsequent compression, we propose three kinds of techniques to select reference trajectories wisely from a large dataset such that the resulting reference set is more compact yet covering most footprints of trajectories in the area of interest. To address the computational issue caused by the large number of combinations of reference trajectories that may exist for resembling a given trajectory, we propose efficient greedy algorithms that run in the blink of an eye and dynamic programming algorithms that can achieve the optimal compression ratio. Compared to existing work on trajectory compression, our framework has few assumptions about data such as moving within a road network or moving with constant direction and speed, and better compression performance with fairly small spatio-temporal loss. In addition, by indexing the reference trajectories directly with an in-memory R-tree and building connections to the raw trajectories with inverted index, we develop an extremely efficient algorithm that can answer spatio-temporal range queries over trajectories in their compressed form. Extensive experiments on a real taxi trajectory dataset demonstrate the superiority of our framework over existing representative approaches in terms of both compression ratio and efficiency.

Predictive spatio-temporal queries are crucial in many applications. Traffic management is an example application, where predictive spatial queries are issued to anticipate jammed areas in advance. Also, location-aware advertising is another example application that targets customers expected to be in the vicinity of a shopping mall in the near future. In this paper, we introduce Panda?, a generic framework for supporting spatial predictive queries over moving objects in Euclidean spaces. Panda? distinguishes itself from previous work in spatial predictive query processing by the following features: (1) Panda? is generic in terms of supporting commonly-used types of queries, (e.g., predictive range, KNN, aggregate queries) over stationary points of interests as well as moving objects. (2) Panda? employees a prediction function that provides accurate prediction even under the absence or the scarcity of the objects' historical trajectories. (3) Panda? is customizable in the sense that it isolates the prediction calculation from query processing. Hence, it enables the injection and integration of user defined prediction functions within its query processing framework. (4) Panda? deals with uncertainties and variabilities in the expected travel time from source to destination in response to incomplete information and/or dynamic changes in the underlying Euclidean space. (5) Panda? provides a controllable parameter that trades low latency responses for computational resources. Experimental analysis proves the scalability of Panda? in evaluating a massive volume of predictive queries over large numbers of moving objects.

<p>Data annotation is the categorization and labelling of data for applications, such as machine learning, artificial intelligence, and data integration. The categorization and labelling are done to achieve a specific use case in relation to solving problems. Existing data annotation systems and modules face imperfections such as knowledge and annotation not being formally integrated, narrow application range, and difficulty to apply on existing database management applications. To analyze and process annotated data, obtain the relationship between different annotations, and capture metainformation in data provenance and probabilistic databases, in this paper, we design a back-end query processing framework as a supplementary interface for the database management system to extend operation to datasets and boost efficiency. The framework utilizes Java language and the MVC model for development to achieve lightweight, cross-platform, and high adaptability identities. The contribution of this paper is mainly reflected in two aspects. The first contribution is to implement query processing, provenance semiring, and semiring homomorphism over annotated data. The second contribution is to combine query processing and provenance with SQL statements in order to enable the database manager to invoke operations to annotation.</p> <p> </p>

Tomorrow marks 5 years since the Curiosity rover’s dramatic landing on the red planet! The rover’s Sample Analysis at Mars (SAM) instrument suite onboard Curiosity is the most complicated instrument NASA has ever sent to another planet. SAM is designed to measure the composition of the atmosphere and solid samples inside Gale Crater on Mars, and help scientists assess the habitability (could a certain place support life?) of environments recorded in in rocks in Gale Crater. The SAM team has made many amazing discoveries, including finding evidence of a habitable environment – a place that life (think tiny microorganisms, not dinosaurs) could have survived if it had been in that spot on Mars, millions of years ago. SAM also detected the first organics (building blocks of life) on Mars, known to have originated on this planet. We’re a group of scientists and engineers from the SAM team, ready to answer your questions about Mars and SAM. We’ll be online from 1:00 to 2:00 pm EST and we will sign our answers. Ask us anything! Paul Mahaffy, SAM Principle Investigator, Director of Solar System Exploration Division, NASA Goddard Space Flight Center Charles Malespin, SAM Deputy Principle Investigator, NASA Goddard Space Flight Center Jen Stern, Planetary Scientist, NASA Goddard Space Flight Center James Lewis, Postdoctoral Fellow, NASA Goddard Space Flight Center Brad Sutter, Planetary Scientist, NASA Johnson Space Flight Center Greg Flesch, Instrument Engineer, NASA Jet Propulsion Laboratory Peter Martin, PhD student, CalTech/NASA Jet Propulsion Laboratory Doug Archer, Planetary Scientist/NASA Johnson Space Center We have now been on Mars for 5 years - WOW. The first year after landing we actually played the Happy Birthday song using our SSIT (solid sample inlet tube). You may find this link interesting https://www.youtube.com/watch?v=uxVVgBAosqg EDIT It has been great answering your questions, we are signing off now!

Integrated access to information that is spread over multiple, distributed, and heterogeneous sources is an important problem in many scienti c and commercial domains. While much work has been done on query processing and choosing plans under cost criteria, very little is known about the important problem of incorporating the information quality aspect into query planning. In this paper we describe a framework for multidatabase query processing that fully includes the quality of information in many facets, such as completeness, timeliness, accuracy, etc. We seamlessly include information quality into a multidatabase query processor based on a view-rewriting mechanism. We model information quality at di erent levels to ultimately nd a set of high-quality queryanswering plans.

This study focuses on the security aspects within microservice architecture, particularly addressing load balancing and role-based access control (RBAC). Exploring the intersection of load balancing techniques and RBAC mechanisms, the research aims to enhance the security posture of microservices. By evalu-ating strategies for efficient load distribution and implementing RBAC proto-cols, the study seeks to fortify the architecture against potential vulnerabili-ties. The integration of load balancing and RBAC not only ensures optimized resource utilization but also strengthens access control measures, bolstering the overall security framework in microservice-based systems

A software production model is developed that integrates process and product and is designed to identify bottlenecks in the production process. Choke points can occur either from process deficiencies or failure to identify and correct extant software defects. NASA Goddard Space Flight Center satellite defect data is used in the analysis because the primary aim is to apply the model to safety critical software. The model applies feedback control to correct anomalies in process and product that may occur. Both predictions and actual defect data are used to identify process and product behavior that do not meet expectations. I. Introduction A CCORDING to, 1 software systems come and go through a series of passages that account for their inception, initial development, productive operation, upkeep, and retirement from one generation to another. We focus on the development and production phases and introduce something different in this research compared with articles about software development process that correctly relate the effectiveness of the process to the quality of the product. We go a step further and introduce the concept of the reliability of the process, both current and future. We perform this analysis by using software defect data from the NASA Goddard Space Flight Center satellite project known as JM1. These data are shown in Table 1. Our goal, recognizing the importance of integrating process and product, 2 is to identify production bottlenecks in the process that cause product delivery to be delayed. In addition, we identify deficiencies in the defect removal process that can lead to product unreliability and delivery schedule delay. The principal features of the production system are defined using process flow charts illustrated in Fig. 1 for a software production and quality control operation. The flow of software modules is from left to right. Each phase has a processing time measured in days and a defect rate. Our model assumes that defects introduced by a process step may pass through downstream steps undetected until an inspection is performed. 3

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Chapter 5 introduces load balancing and replication. They are essential aspects that are complementary to each other and need to be considered in the design of P2P systems in order to bring efficiency to query processing. While load balancing helps the system to reduce the query latency and avoid the problem of failure at overloaded nodes, replication deals with the problem of bottleneck in query processing at nodes holding popular data items. In this chapter, we discuss load balancing from two point of view: when should load balancing be triggered and, when triggered, how is it performed. For replication, we look at solutions to determine which object should be replicated, how many replicas are enough, where replicas are stored, and how to maintain consistency of replicas with their original data. Besides introducing general concepts and solutions of load balancing and replication, we also present specific load balancing and replication strategies used in concrete P2P systems.

Autonomic computing for spacecraft ground systems increases the system reliability and reduces the cost of spacecraft operations and software maintenance. In this paper, we present an autonomic computing solution for spacecraft ground systems at NASA Goddard Space Flight Center (GSFC), which consists of an open standard for the message oriented architecture referred to as GMSEC architecture, the GSFC Mission Services Evolution Center, and an autonomic computing tool, Criteria Action Table (CAT). This solution has been used in many upgraded ground systems for NASA's missions, and provides a framework for developing solutions with higher autonomic maturity.

Engineering Design and Development DivisionScientific and Commercial Systems CorporationAlexandria, VirginiaABSTRACTThe historically high toll in human lives lost to natural disasters such as hurricanes, tornadoes, floods, and otherprogressive events signals the need for some type of personal warning that alerts people to the need to evacuateor otherwise protect themselves in the face of an advancing threat. Traditional warning services, which rely onbroadcasts by the mass media in the metropolitan areas of the United States, achieve measurable success indisseminating warnings. However, warnings to isolated populations that exist in the U.S. and elsewhere in theworld may be poor to effectively nonexistent, especially in the many archipelagoes. Earth Alert, a joint projectof NASA Goddard Space Flight Center (GSFC) and Scientific and Commercial Systems Corporation (SCSC), istargeted at development of a simple, low-cost means for providing timely warning to otherwise isolated popula-tions. The project uses appropriate relay capabilities of U.S. satellites already in orbit, and thus avoids the high-cost development and launch of dedicated resources.Key words: GOES, emergency warning, WEFAX, repeater1. INTRODUCTIONIn an August 13, 1992 meeting with SCSC managers, the Chief of NASA GSFC International Data SystemsOffice raised the idea of a technology transfer project to provide timely personal warning to isolated populationsthreatened by natural disaster. The specific suggestion was that some capabilities of on-orbit satellite systemscould be diverted to provide enough warning to permit these populations to prepare for the threat of naturaldisasters such as hurricanes, tornadoes, orfloods. The NASA official was armed witha wealth ofexamples ofserious weather

The Formation Flying Test Bed (FFTB) at NASA Goddard Space Flight Center (GSFC) is being developed as a modular, hybrid dynamic simulation facility employed for end-to-end guidance, navigation, and control (GN&C) analysis and design for formation flying clusters and constellations of satellites. The FFTB will support critical hardware and software technology development to enable current and future missions for NASA, other government agencies, and external customers for a wide range of missions, particularly those involving distributed spacecraft operations. The initial capabilities of the FFTB are based upon an integration of high fidelity hardware and software simulation, emulation, and test platforms developed at GSFC in recent years; including a high-fidelity GPS simulator which has been a fundamental component of the Guidance, Navigation, and Control Center's GPS Test Facility. The FFTB will be continuously evolving over the next several years from a tool with initial capabilities in GPS navigation hardware/software-in-the-loop analysis and closed loop GPS-based orbit control algorithm assessment to one with cross-link communications and relative navigation analysis and simulation capability. Eventually the FFTB will provide full capability to support all aspects of multi-sensor, absolute and relative position determination and control, in all (attitude and orbit) degrees of freedom, as well as information management for satellite clusters and constellations. In this paper we focus on the architecture for the FFTB as a general GN&C analysis environment for the spacecraft formation flying community inside and outside of NASA GSFC and we briefly reference some current and future activities which will drive the requirements and development.