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Academic e-mail overload and the burden of “Academic Spam”
This article presents an editorial perspective on the challenges associated with e-mail management for academic physicians. We include 2-week analysis of our own e-mails as illustrations of the e-mail volume and content. We discuss the contributors to high e-mail volumes, focusing especially on unsolicited e-mails from medical/scientific conferences and open-access journals (sometimes termed “academic spam emails”), as these e-mails comprise a significant volume and are targeted to physicians and scientists. Our 2-person sample is consistent with studies showing that journals that use mass e-mail advertising have low rates of inclusion in recognized journal databases/resources. Strategies for managing e-mail are discussed and include unsubscribing, blocking senders or domains, filtering e-mails, managing one’s inbox, limiting e-mail access, and e-mail etiquette. Academic institutions should focus on decreasing the volume of unsolicited e-mails, fostering tools to manage e-mail overload, and educating physicians including trainees about e-mail practices, predatory journals, and scholarly database/resources.
5/20/2020 2:42:45 AM +00:00
Lecture Principles of distributed database systems - Chapter 18: Current issues
Lecture Principles of distributed database systems - Chapter 18: Current issues. In this chapter students will be able to: Data stream management, cloud data management, inputs & outputs, data stream management system (DSMS), DSMSs – novel problems, abstract system architecture, stream data models,...
5/19/2020 9:36:36 PM +00:00
Lecture Principles of distributed database systems - Chapter 17: Web data management
Lecture Principles of distributed database systems - Chapter 17: Web data management. In this chapter students will be able to: Web data management, web models, web search and querying, distributed XML processing, properties of web data, web graph, web data modeling, search engine architecture,...
5/19/2020 9:36:30 PM +00:00
Lecture Principles of distributed database systems - Chapter 16: Peer-to-peer data management
In this chapter students will be able to: Peer-to-peer data management, why high-level P2P data sharing? problem definition, peer reference architecture, potential benefits of P2P systems, P2P vs traditional distributed DBMS,...
5/19/2020 9:36:23 PM +00:00
Lecture Principles of distributed database systems - Chapter 15: Distributed object DBMS
Lecture Principles of distributed database systems - Chapter 15: Distributed object DBMS. In this chapter students will be able to: Distributed object DBMS, object models, object distribution, fundamental concepts, object distribution, fragmentation alternatives, horizontal fragmentation,...
5/19/2020 9:36:17 PM +00:00
Lecture Principles of distributed database systems - Chapter 14: Parallel database systems
Lecture Principles of distributed database systems - Chapter 14: Parallel database systems. In this chapter students will be able to: Parallel database systems, data placement and query processing, load balancing, database clusters, the database problem, multiprocessor objectives,...
5/19/2020 9:36:11 PM +00:00
Lecture Principles of distributed database systems - Chapter 13: Data replication
Lecture Principles of distributed database systems - Chapter 13: Data replication. In this chapter students will be able to: Data replication, consistency criteria, replication protocols, replication and failure management, execution model, replication issues, transactional consistency, update management strategies,...
5/19/2020 9:36:05 PM +00:00
Lecture Principles of distributed database systems - Chapter 12: Distributed reliability
In this chapter students will be able to: Fundamental definitions, faults to failures, types of faults, fault classification, fault tolerance measures, fault-tolerance measures, fault-tolerance measures, types of failures, local recovery management – architecture,...
5/19/2020 9:35:59 PM +00:00
Lecture Principles of distributed database systems - Chapter 11: Distributed concurrency control
Lecture Principles of distributed database systems - Chapter 11: Distributed concurrency control. In this chapter students will be able to: Concurrency control, execution history (or schedule), formalization of history, complete schedule, schedule definition, serial history, serializable history, serializability in distributed DBMS,...
5/19/2020 9:35:52 PM +00:00
Lecture Principles of distributed database systems - Chapter 10: Transaction concepts and models
In this chapter students will be able to: Transaction, transaction example – a simple SQL query, example transaction – SQL Version, termination of transactions, characterization, formalization, consistency degrees (cont’d), SQL-92 isolation levels,...
5/19/2020 9:35:46 PM +00:00
Lecture Principles of distributed database systems - Chapter 9: Multidatabase query processing
Lecture Principles of distributed database systems - Chapter 9: Multidatabase query processing. In this chapter students will be able to: query rewriting, optimization issues, mediator/wrapper architecture, advantages of M/W architecture, issues in MDB query processing, component DBMS autonomy,...
5/19/2020 9:35:40 PM +00:00
Lecture Principles of distributed database systems - Chapter 8: Distributed query optimization
Lecture Principles of distributed database systems - Chapter 8: Distributed query optimization. In this chapter students will be able to: Global query optimization, cost-based optimization, query optimization process, search space, search strategy, cost functions, total cost, total cost factors, response time, optimization statistics,...
5/19/2020 9:35:33 PM +00:00
Lecture Principles of distributed database systems - Chapter 7: Query decomposition and localization
Lecture Principles of distributed database systems - Chapter 7: Query decomposition and localization. In this chapter students will be able to: Query decomposition, normalization, restructuring – transformation rules, equivalent query, provides parallellism, eliminates unnecessary work, reduction for PHF, reduction for hybrid fragmentation.
5/19/2020 9:35:25 PM +00:00
Lecture Principles of distributed database systems - Chapter 6: Distributed query processing
Lecture Principles of distributed database systems - Chapter 6: Distributed query processing. In this chapter students will be able to: Overview, query decomposition and localization, distributed query optimization.
5/19/2020 9:35:19 PM +00:00
Lecture Principles of distributed database systems - Chapter 5: Semantic data control
Lecture Principles of distributed database systems - Chapter 5: Semantic data control. In this chapter students will be able to: view management, data security, semantic integrity control.
5/19/2020 9:35:13 PM +00:00
Lecture Principles of distributed database systems - Chapter 4: Database integration
Lecture Principles of distributed database systems - Chapter 4: Database integration. In this chapter students will be able to: Schema matching, schema mapping, problem definition, integration alternatives, data warehouse approach, GCS/LCS relationship,...
5/19/2020 9:35:07 PM +00:00
Lecture Principles of distributed database systems - Chapter 3: Distributed database design
Lecture Principles of distributed database systems - Chapter 3: Distributed database design. In this chapter students will be able to: Design problem, dimensions of the problem, distribution design, top-down design, distribution design issues, fragmentation alternatives – horizontal, degree of fragmentation,...
5/19/2020 9:35:00 PM +00:00
Lecture Principles of distributed database systems - Chapter 2: Background
Lecture Principles of distributed database systems - Chapter 2: Background. In this chapter students will be able to: relational model, relational database systems, computer networks, relation schemes and instances, relation schemes, repetition anomaly,...
5/19/2020 9:34:50 PM +00:00
Lecture Principles of distributed database systems - Chapter 1: Introduction
Lecture Principles of distributed database systems - Chapter 1: Introduction. In this chapter students will be able to: What is a distributed DBMS, distributed DBMS Architecture.
5/19/2020 9:34:44 PM +00:00
IT-Tree và thuật toán Apriori
Khám phá itemsets là công việc quan trọng trong khai thác dữ liệu. Nhờ đó mà ta có thể khai thác luật kết hợp từ các itemsets đó. Tuy nhiên, không gian tìm kiếm trong giai đoạn tìm các itemsets cần thiết thì rất lớn theo từng bước, độ dài k của các item.
5/19/2020 6:31:53 PM +00:00
Bài giảng Chương 4: Các thuật toán tìm kiếm
Nội dung bài giảng trình bày khái niệm tìm kiếm; bài toán tìm kiếm; các thuật toán tìm kiếm; tìm kiếm trên dãy chưa sắp; tìm kiếm tuần tự; tìm kiếm tuần tự cải tiến; tìm kiếm tuần tự trên dãy đã sắp... Để nắm chắc kiến thức mời các bạn cùng tham khảo bài giảng Chương 4: Các thuật toán tìm kiếm.
5/5/2020 12:28:16 AM +00:00
Lecture Database Systems - Lecture 32
After completing this chapter, students will be able to: The object-relational data model, which extends the relational data model to support complex data types, type inheritance, and object identity. The chapter also describes database access from object-oriented programming languages.
5/4/2020 5:22:09 PM +00:00
Lecture Database Systems - Lecture 31
After completing this chapter, students will be able to: Advanced issues in application development, including performance tuning, performance benchmarks, database-application testing, and standardization.
5/4/2020 5:22:03 PM +00:00
Lecture Database Systems - Lecture 30
After completing this chapter, students will be able to: Transaction-processing monitors, transactional workflows, electronic commerce, high-performance transaction systems, real-time transaction systems, and long-duration transactions.
5/4/2020 5:21:57 PM +00:00
Lecture Database Systems - Lecture 29
After completing this chapter, students will be able to: Basic concepts, tree-structure diagrams, data-retrieval facility, update facility, virtual records, mapping of hierarchies to files, the IMS database system.
5/4/2020 5:21:51 PM +00:00
Lecture Database Systems - Lecture 28
This chapter provides an overview of the database-design process, with major emphasis on database design using the entity-relationship data model. The entity-relationship data model provides a high-level view of the issues in database design, and of the problems that we encounter in capturing the semantics of realistic applications within the constraints of a data model. UML class-diagram notation is also covered in this chapter.
5/4/2020 5:21:45 PM +00:00
Lecture Database Systems - Lecture 27
After completing this chapter, students will be able to: Remaining activities/steps in building conceptual data model, logical database design, purpose of normalization, data redundancy and update anomalies, functional dependencies.
5/4/2020 5:21:39 PM +00:00
Lecture Database Systems - Lecture 26
This chapter presented a high-level view of the database design process, and in this chapter we focus on the logical database design or data model mapping step of database design. We present the procedures to create a relational schema from an Entity-Relationship or an Enhanced ER schema.
5/4/2020 5:21:33 PM +00:00
Lecture Database Systems - Lecture 25
After completing this chapter, students will be able to: Computer organization, data representation, integer arithmetic, binary representation, floating point representation, machine instruction characteristics, instruction cycles, types of operands, pentium and power PC data types, microporessor bus structure, address, data.
5/4/2020 5:21:27 PM +00:00
Lecture Database Systems - Lecture 24
After completing this chapter, students will be able to: Classification of entities, attributes on relationships, structural constraints, multiplicity, binary/complex relationships, structural constraints, multiplicity, connection traps.
5/4/2020 5:21:21 PM +00:00