BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

https://www1.montpellier.inra.fr/lameta/articles/5.4.2_POLLINATION.pdf

Economic valuation of the vulnerability of world agriculture confronted with pollinator decline

The problem of answering queries using views is to find efficient methods of answering a query using a set of previously defined materialized views over the database, rather than accessing the database relations. The problem has recently received significant attention because of its relevance to a wide variety of data management problems. In query optimization, finding a rewriting of a query using a set of materialized views can yield a more efficient query execution plan. To support the separation of the logical and physical views of data, a storage schema can be described using views over the logical schema. As a result, finding a query execution plan that accesses the storage amounts to solving the problem of answering queries using views. Finally, the problem arises in data integration systems, where data sources can be described as precomputed views over a mediated schema. This article surveys the state of the art on the problem of answering queries using views, and synthesizes the disparate works into a coherent framework. We describe the different applications of the problem, the algorithms proposed to solve it and the relevant theoretical results.

/pdf/answering-queries-using-views-a-survey-4aug5icc6d.pdf

Answering queries using views: A survey

An intelligent automated assistant system engages with the user in an integrated, conversational manner using natural language dialog, and invokes external services when appropriate to obtain information or perform various actions. The system can be implemented using any of a number of different platforms, such as the web, email, smartphone, and the like, or any combination thereof. In one embodiment, the system is based on sets of interrelated domains and tasks, and employs additional functionally powered by external services with which the system can interact.

Intelligent Automated Assistant

Schema matching is the task of finding semantic correspondences between elements of two schemas. It is needed in many database applications, such as integration of web data sources, data warehouse loading and XML message mapping. To reduce the amount of user effort as much as possible, automatic approaches combining several match techniques are required. While such match approaches have found considerable interest recently, the problem of how to best combine different match algorithms still requires further work. We have thus developed the COMA schema matching system as a platform to combine multiple matchers in a flexible way. We provide a large spectrum of individual matchers, in particular a novel approach aiming at reusing results from previous match operations, and several mechanisms to combine the results of matcher executions. We use COMA as a framework to comprehensively evaluate the effectiveness of different matchers and their combinations for real-world schemas. The results obtained so far show the superiority of combined match approaches and indicate the high value of reuse-oriented strategies.

/pdf/coma-a-system-for-flexible-combination-of-schema-matching-4rgyvphehs.pdf

COMA: a system for flexible combination of schema matching approaches

Statistical Databases

We consider nested relations whose schemes are structured as trees, called scheme trees, and introduce a normal form for such relations, called the nested normal form. Given a set of attributes U, and a set of multivalued dependencies (MVDs) M over these attributes, we present an algorithm to obtain a nested normal form decomposition of U with respect to M. Such a decomposition has several desirable properties, such as explicitly representing a set of full and embedded MVDs implied by M, and being a faithful and nonredundant representation of U. Moreover, if the given set of MVDs is conflict-free, then the nested normal form decomposition is also dependency-preserving. Finally, we show that if M is conflict-free, then the set of root-to-leaf paths of scheme trees in nested normal form decomposition is precisely the unique 4NF decomposition [9, 16] of U with respect to M.

A new normal form for nested relations

The number of personal multimedia objects, such as digital photographs and videos, are exploding on the web through popular sites such as Flickr, YouTube, and FaceBook hosting billions of user-created items. Semantic annotation can be an extremely effective way to search, browse, and organize media objects, but can require extensive human involvement. In this work, we show how semantic metadata about social networks and family relationships can be used to improve semantic annotation suggestion. This includes up to 82% recall for people annotations as well as recall improvements of 20-26% in tag annotation recall when no annotation history is available. In addition, utilizing relationships among people while searching can provide at least 28% higher recall and 55% higher precision than keyword search while still being up to 12 times faster. Methods are evaluated on real personal photo collections containing up to 120k photos from Flickr as well as 41k annotated photos from our prototype system.

Annotation suggestion and search for personal multimedia objects on the web

As a simple XML query language but with enough expressive power, XPath has become very popular. To expedite evaluation of XPath queries, we consider the problem of rewriting XPath queries using materialized XPath views. This problem is very important and arises not only from query optimization in server side but also from semantic caching in client side. We consider the problem of deciding whether there exists a rewriting of a query using XPath views and the problem of finding minimal rewritings. We first consider those two problems for a very practical XPath fragment containing the descendent, child, wildcard and branch features. We show that the rewriting existence problem is coNP-hard and the problem of finding minimal rewritings is Σp3. We also consider those two rewriting problems for three subclasses of this XPath fragment, each of which contains child feature and two of descendent, wildcard and branch features, and show that both rewriting problems can be polynomially solved. Finally, we give an algorithm for finding minimal rewritings, which is sound for the XPath fragment, but is also complete and runs in polynomial time for its three subclasses.

/pdf/rewriting-xpath-queries-using-materialized-views-zpd4jcruhc.pdf

Rewriting XPath queries using materialized views

This paper describes a scheme to utilize semantic integrity constraints in optimizing a user specified query. The scheme uses a graph theoretic approach to identify redundant join clauses and redundant restriction clauses specified in a user query. An algorithm is suggested to eliminate such redundant joins and avoid unnecessary restrictions. In addition to these eliminations, the algorithm aims to introduce as many restrictions on indexed attributes as possible, thus yielding an equivalent, but potentially more profitable, form of the original query.

Z. Meral Ozsoyoglu

Papers

Statistical Databases

A new normal form for nested relations

Annotation suggestion and search for personal multimedia objects on the web

Rewriting XPath queries using materialized views

A system for semantic query optimization