In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit- able because of the difference between the object-oriented data model(OODM)and the conventional da- ta models(e.g.rela...In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit- able because of the difference between the object-oriented data model(OODM)and the conventional da- ta models(e.g.relational data model).In this paper,transaction models for advanced databuse applica- tions are reviewed and their shortcomings are analyzed.Exchangeability of operations is proposed in- stead of commuativity and recoverability for using more semantics in transaction management.As a result,an object-oriented transaction model(in short,OOTM)is presented.It is not modeled for some special application,but directly based on object-oriented paradigms.A transaction is regarded as an interpretation of a method.Each transaction(even subtransactions)keeps relative ACID(Atomicity, Consistency,Isolation,Durability )properties,therefore the special problems appearing in OODBSs such as“long transactions”,“visibility of inconsistent database state”can be solved.展开更多
At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to real...At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to realize real bidding for access to grid in practice in a short term. This paper presents one kind of power-exchanging transaction model among price-varied power plants, which will be beneficial to price-varied power plants without any loss of profits of them and guarantee state-owned assets profits in minimum loss with no promotion of average price limit by power plants. Under ideal conditions, the computation results showed the sufficiency and necessity of power-exchanging transaction and maximum similarity with the requirements of optimized resources disposition in economics. The presented model is shown to be full of practicability and has been used in some part of power market.展开更多
The application collaboration was addressed to provide energy-efficient data services for distributed sensing applications to collaboratively interacting to achieve a desired global objective not detectable by any sin...The application collaboration was addressed to provide energy-efficient data services for distributed sensing applications to collaboratively interacting to achieve a desired global objective not detectable by any single cluster. An epoch-based transaction model was proposed by using the concept of sphere of control (SoC), and a collaborative sensing application can be dynamically formed as a nested architecture composed of time-synchronized applications. By loosening the rigid constraints of ACID to adapt the requirements of sensor networks, the submission, rollback and consistency rules ware educed and a two-phrase submission protocol was designed. Finally, it was illustrated that the model is capable of providing an adaptive formal template for sensing application collaboration. Our performance evaluations show that by applying the two-phrase submission protocol, we can significantly improve the number of reported answers and response time, raise resource utilization, and reduce the energy cansumption and data loss.展开更多
Composite Web services provide promising prospects for conducting cross-organizational Web service transactions. Such transactions generally require longer processing time and manipulate financially critical data. To ...Composite Web services provide promising prospects for conducting cross-organizational Web service transactions. Such transactions generally require longer processing time and manipulate financially critical data. To efficiently manage these Web services transactions, isolation is commonly relaxed, but inconsistency will be caused by concurrently executing isolation-relaxing transactions. This article proposes an extension to the WS-Business Activity Protocol, which ensures the consistent executions of isolation-relaxing Web service transactions, and which is based on transaction dependency graphs distributed over multiple nodes. Furthermore, this article presents several algorithms implementing the protocol, and introduces the implement of a prototype system.展开更多
Many business processes in enterprise applications are both long running and transactional in nature. However, no current transaction model can provide full transaction support for such long running business processes...Many business processes in enterprise applications are both long running and transactional in nature. However, no current transaction model can provide full transaction support for such long running business processes. This paper proposes a new transaction model, the pessimistic predicate/transform (PP/T) model, which can provide full transaction support for long running business processes. A framework was proposed on the enterprise JavaBeans platform to implement the PP/T model. The framework enables application developers to focus on the business logic, with the underlying platform providing the required transactional semantics. The development and maintenance effort are therefore greatly reduced. Simulations show that the model has a sound concurrency management ability for long running business processes.展开更多
文摘In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit- able because of the difference between the object-oriented data model(OODM)and the conventional da- ta models(e.g.relational data model).In this paper,transaction models for advanced databuse applica- tions are reviewed and their shortcomings are analyzed.Exchangeability of operations is proposed in- stead of commuativity and recoverability for using more semantics in transaction management.As a result,an object-oriented transaction model(in short,OOTM)is presented.It is not modeled for some special application,but directly based on object-oriented paradigms.A transaction is regarded as an interpretation of a method.Each transaction(even subtransactions)keeps relative ACID(Atomicity, Consistency,Isolation,Durability )properties,therefore the special problems appearing in OODBSs such as“long transactions”,“visibility of inconsistent database state”can be solved.
基金This research is supported by Special Science Fund on University Doctor Science Point of the Department of Education of China (20020698027).
文摘At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to realize real bidding for access to grid in practice in a short term. This paper presents one kind of power-exchanging transaction model among price-varied power plants, which will be beneficial to price-varied power plants without any loss of profits of them and guarantee state-owned assets profits in minimum loss with no promotion of average price limit by power plants. Under ideal conditions, the computation results showed the sufficiency and necessity of power-exchanging transaction and maximum similarity with the requirements of optimized resources disposition in economics. The presented model is shown to be full of practicability and has been used in some part of power market.
基金National Natural Science Foundation of China under Grant No60073045the National Defense Pre-Research Foundation of China under Grant No.00J15.3.3.J W529
文摘The application collaboration was addressed to provide energy-efficient data services for distributed sensing applications to collaboratively interacting to achieve a desired global objective not detectable by any single cluster. An epoch-based transaction model was proposed by using the concept of sphere of control (SoC), and a collaborative sensing application can be dynamically formed as a nested architecture composed of time-synchronized applications. By loosening the rigid constraints of ACID to adapt the requirements of sensor networks, the submission, rollback and consistency rules ware educed and a two-phrase submission protocol was designed. Finally, it was illustrated that the model is capable of providing an adaptive formal template for sensing application collaboration. Our performance evaluations show that by applying the two-phrase submission protocol, we can significantly improve the number of reported answers and response time, raise resource utilization, and reduce the energy cansumption and data loss.
基金supported by the National Key Technology R&D Program (2007BAH17B04)Natural Science Foundation of Jiangsu Province (BK2007603)+1 种基金Research Climbing Project of NJUPT (NY207062)Qin-Lan Project of NJUPT (NY208024)
文摘Composite Web services provide promising prospects for conducting cross-organizational Web service transactions. Such transactions generally require longer processing time and manipulate financially critical data. To efficiently manage these Web services transactions, isolation is commonly relaxed, but inconsistency will be caused by concurrently executing isolation-relaxing transactions. This article proposes an extension to the WS-Business Activity Protocol, which ensures the consistent executions of isolation-relaxing Web service transactions, and which is based on transaction dependency graphs distributed over multiple nodes. Furthermore, this article presents several algorithms implementing the protocol, and introduces the implement of a prototype system.
基金Supported by the National Key Basic Research and Development (973) Program of China (No. 2002CB312005), and the National High-Tech Research and Development (863) Program of China (No. 2003AA115440)
文摘Many business processes in enterprise applications are both long running and transactional in nature. However, no current transaction model can provide full transaction support for such long running business processes. This paper proposes a new transaction model, the pessimistic predicate/transform (PP/T) model, which can provide full transaction support for long running business processes. A framework was proposed on the enterprise JavaBeans platform to implement the PP/T model. The framework enables application developers to focus on the business logic, with the underlying platform providing the required transactional semantics. The development and maintenance effort are therefore greatly reduced. Simulations show that the model has a sound concurrency management ability for long running business processes.