The cost of increased transactional correctness and durability in distributed databases

2016 ◽

Vol 32 (1) ◽

pp. 47-60

Author(s):

Nga Thúy Mai

Keyword(s):

Relational Databases ◽

Distributed Databases ◽

Data Communication ◽

Object Oriented ◽

Database System ◽

Distributed Data ◽

Distributed Object ◽

Data Objects ◽

The Cost ◽

Object Oriented Database

Class fragmentation and allocation is an important technique to improve the performance of a distributed object oriented database system. The class fragmentation is to split a class into smaller pieces in distributed databases aims to reduce the access to unnecessary data, the allocation is to locate fragmented classes into the sites in the connected network properly to reduce the cost of data transmission. Classes in object databases include attributes describing the characteristics of the object, methods describing the behavior, and relationships with objects with other classes, including relations inheritance. With such characteristics, class fragmentation and allocation in the distributed object oriented database system is more complex than fragmentation technique and design of relational databases. Fragmentation techniques applied in the design of distributed object-oriented database today often do not use cost between the sites, fragments are allocated to the site after getting a fragmentation method of data objects. This paper proposes an algorithm of fragmentation and allocation simultaneously, including the cost of data communication between the sites used for fragmentation to reduce communication costs when processing and querying distributed data.

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Blockchain-Based Medical Record Management with Biofeedback Information

Smart Biofeedback - Perspectives and Applications ◽

10.5772/intechopen.94370 ◽

2020 ◽

Author(s):

Hui Li Wang ◽

Shao-I Chu ◽

Jiun-Han Yan ◽

Yu-Jung Huang ◽

I-Yueh Fang ◽

...

Keyword(s):

Medical Record ◽

Information Management ◽

Data Storage ◽

Medical Records ◽

Information Exchange ◽

Distributed Databases ◽

Record Management ◽

Management Framework ◽

Medical Health ◽

The Cost

Blockchain is a new emerging technology of distributed databases, which guarantees the integrity, security and incorruptibility of data by means of the cryptography. Such features are suitable for secure and reliable data storage. This chapter investigates the blockchain-based architecture with applications to medical health record or biofeedback information management. This framework employs the smart contract to establish a medical record management system to ensure the privacy of patients. Moreover, the blockchain technique accelerates the medical record or information exchange such that the cost of human resource is significant reduced. All patients can manage their individual medical records and information easily in the different hospitals and clinics. They also have the privilege to deal with and authorize personal medical records in the proposed management framework.

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Dynamic Cost Ant Colony Algorithm to Optimize Query for Distributed Database Based on Quantum-Inspired Approach

Symmetry ◽

10.3390/sym13010070 ◽

2021 ◽

Vol 13 (1) ◽

pp. 70

Author(s):

Sayed A. Mohsin ◽

Ahmed Younes ◽

Saad M. Darwish

Keyword(s):

Query Processing ◽

Ant Colony Algorithm ◽

Distributed Databases ◽

Distributed Database ◽

Ant Colony ◽

Local Optimum ◽

Probabilistic Algorithms ◽

Hybrid Strategy ◽

Search Spaces ◽

The Cost

A distributed database model can be effectively optimized through using query optimization. In such a model, the optimizer attempts to identify the most efficient join order, which minimizes the overall cost of the query plan. Successful query processing largely relies on the methodology implemented by the query optimizer. Many researches are concerned with the fact that query processing is considered an NP-hard problem especially when the query becomes bigger. Regarding large queries, it has been found that heuristic methods cannot cover all search spaces and may lead to falling in a local minimum. This paper examines how quantum-inspired ant colony algorithm, a hybrid strategy of probabilistic algorithms, can be devised to improve the cost of query joins in distributed databases. Quantum computing has the ability to diversify and expand, and thus covering large query search spaces. This enables the selection of the best trails, which speeds up convergence and helps avoid falling into a local optimum. With such a strategy, the algorithm aims to identify an optimal join order to reduce the total execution time. Experimental results show that the proposed quantum-inspired ant colony offers a faster convergence with better outcome when compared with the classic model.

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The IBM-PC in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165525 ◽

1996 ◽

Vol 54 ◽

pp. 612-613

Author(s):

James F. Mancuso

Keyword(s):

Head Start ◽

Image Acquisition ◽

Cost Effective ◽

Financial Applications ◽

Number Of Factors ◽

Instrument Control ◽

The Cost ◽

Training And Support ◽

Control Image ◽

Ibm Pc

IBM PC compatible computers are widely used in microscopy for applications ranging from control to image acquisition and analysis. The choice of IBM-PC based systems over competing computer platforms can be based on technical merit alone or on a number of factors relating to economics, availability of peripherals, management dictum, or simple personal preference.IBM-PC got a strong “head start” by first dominating clerical, document processing and financial applications. The use of these computers spilled into the laboratory where the DOS based IBM-PC replaced mini-computers. Compared to minicomputer, the PC provided a more for cost-effective platform for applications in numerical analysis, engineering and design, instrument control, image acquisition and image processing. In addition, the sitewide use of a common PC platform could reduce the cost of training and support services relative to cases where many different computer platforms were used. This could be especially true for the microscopists who must use computers in both the laboratory and the office.

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New Feasible Concepts of Aberration Correction for Realizing High-Resolution Electron Microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100179762 ◽

1990 ◽

Vol 48 (1) ◽

pp. 202-203

Author(s):

H. Rose

Keyword(s):

Spherical Aberration ◽

Wave Length ◽

Electron Wave ◽

Optical Lens ◽

Resolution Electron ◽

Rotationally Symmetric ◽

Electron Microscopes ◽

The Cost ◽

Imaging Performance ◽

Acceleration Voltage

The imaging performance of the light optical lens systems has reached such a degree of perfection that nowadays numerical apertures of about 1 can be utilized. Compared to this state of development the objective lenses of electron microscopes are rather poor allowing at most usable apertures somewhat smaller than 10-2 . This severe shortcoming is due to the unavoidable axial chromatic and spherical aberration of rotationally symmetric electron lenses employed so far in all electron microscopes.The resolution of such electron microscopes can only be improved by increasing the accelerating voltage which shortens the electron wave length. Unfortunately, this procedure is rather ineffective because the achievable gain in resolution is only proportional to λ1/4 for a fixed magnetic field strength determined by the magnetic saturation of the pole pieces. Moreover, increasing the acceleration voltage results in deleterious knock-on processes and in extreme difficulties to stabilize the high voltage. Last not least the cost increase exponentially with voltage.

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