scholarly journals A Model for Ranking and Selecting Integrity Tests in a Distributed Database

2012 ◽  
pp. 138-157
Author(s):  
Ali Amer Alwan ◽  
Hamidah Ibrahim ◽  
Nur Izura Udzir
Keyword(s):  
Distributed Database ◽  
Local Processing ◽  
Suitable Test ◽  
Constraint Checking ◽  
Proposed Model ◽  
Integrity Tests ◽  
Rank And Select

Checking the consistency of a database state generally involves the execution of integrity tests on the database, which verify whether the database is satisfying its constraints or not. This paper presents the various types of integrity tests as reported in previous works and discusses how these tests can significantly improve the performance of the constraint checking mechanisms without limiting to a certain type of test. Having these test alternatives and selecting the most suitable test is an issue that needs to be tackled. In this regard, the authors propose a model to rank and select the suitable test to be evaluated given several alternative tests. The model uses the amount of data transferred across the network, the number of sites involved, and the amount of data accessed as the parameters in deciding the suitable test. Several analyses have been performed to evaluate the proposed model, and results show that the model achieves a higher percentage of local processing as compared to the previous selected strategies.

scholarly journals A Model for Ranking and Selecting Integrity Tests in a Distributed Database

2010 ◽  
Vol 5 (3) ◽  
pp. 65-84
Author(s):  
Ali Amer Alwan ◽  
Hamidah Ibrahim ◽  
Nur Izura Udzir
Keyword(s):  
Distributed Database ◽  
Local Processing ◽  
Suitable Test ◽  
Constraint Checking ◽  
Proposed Model ◽  
Integrity Tests ◽  
Rank And Select

Checking the consistency of a database state generally involves the execution of integrity tests on the database, which verify whether the database is satisfying its constraints or not. This paper presents the various types of integrity tests as reported in previous works and discusses how these tests can significantly improve the performance of the constraint checking mechanisms without limiting to a certain type of test. Having these test alternatives and selecting the most suitable test is an issue that needs to be tackled. In this regard, the authors propose a model to rank and select the suitable test to be evaluated given several alternative tests. The model uses the amount of data transferred across the network, the number of sites involved, and the amount of data accessed as the parameters in deciding the suitable test. Several analyses have been performed to evaluate the proposed model, and results show that the model achieves a higher percentage of local processing as compared to the previous selected strategies.

scholarly journals A New Scalable and Expandable Access Control Model for Distributed Database Systems in Data Security

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Mehmet Guclu ◽  
Cigdem Bakir ◽  
Veli Hakkoymaz
Keyword(s):  
Access Control ◽  
Database Systems ◽  
Distributed Database ◽  
Control Model ◽  
Access Control Model ◽  
Distributed Database Systems ◽  
Access Control Models ◽  
Control Models ◽  
Proposed Model ◽  
Private Network

Access control models are an important tool developed for securing today’s data systems. Institutions use the access control models specifically to define who their employees are, what they can do, which resources they can reach, and which processes they can perform and use them to manage the whole process. This is a very hard and costly process for institutions with distributed database systems. However, access control models cannot be implemented in a qualified way due to the fact that the conditions for defining users’ demands to reach resources distributed on different servers, one of which is consequentially bound to the other, the verification and authorization of those user demands, and being able to monitor the actions of the users cannot be configured in an efficient way all the time. With our model suggested in this study, the aim is to automatically calculate the permissions and access levels of all users defined in the distributed database systems for the objects, and, in this way, we will reach a more efficient decision as to which objects the users can access while preventing their access to the information they do not need. Our proposed model in this study has been applied to real life data clusters from organizations providing health and education services and a public service. With the proposed model, all models have been run on servers sharing resources in a private network. The performance of the proposed model has been compared to that of traditional access models. It was confirmed that the proposed model presented an access control model providing more accurate access level results as well as being scalable to many distributed database systems.

PcAVP - Adaptable Vertical Partitioning Algorithm Based on Privacy Constraint for Distributed Database System

2013 ◽  
Vol 303-306 ◽  
pp. 2139-2143
Author(s):  
Jie Jiang ◽  
Zhu Yan Gu ◽  
Tie Ming Chen
Keyword(s):  
Privacy Protection ◽  
Data Privacy ◽  
Distributed Database ◽  
Constraint Checking ◽  
Vertical Partitioning ◽  
Data Privacy Protection ◽  
Partitioning Algorithm ◽  
Distributed Database System ◽  
Specific Number ◽  
Best Fit

Vertical partitioning is a process of generating fragments, each of which is composed of attributes with high affinity. It is widely used in the distributed database to improve the efficiency of system by reducing the connection between the table access operations. The current research on vertical partitioning is mainly focused on how to measure the "affinity" to get the best-fit vertical partitioning and the n-way vertical partitioning which support generating the specific number of fragments required by the user. In this paper, we propose a vertical partitioning algorithm based on privacy constraint. It supports both the best-fit vertical partitioning and the n-way vertical partitioning. It also provides the data privacy protection by privacy constraint checking. We conduct several experimental results to show that our algorithm not only keeps higher efficiency, but also provides data privacy protection.

scholarly journals Plan de negocios para la exportación de empanizados de calamar gigante al mercado de Estados Unidos

2007 ◽  
Vol 12 (22) ◽  
pp. 129-143
Author(s):  
Liliana Baca ◽  
◽  
Andreína González ◽  
José Méndez ◽  
Tatiana Urrunaga ◽  
...  
Keyword(s):  
Business Plan ◽  
The United States ◽  
International Markets ◽  
Raw Material ◽  
Added Value ◽  
Local Processing ◽  
Marketing Plan ◽  
Critical Factors ◽  
Giant Squid ◽  
Proposed Model

This article develops a business plan to introduce giant squid in markets in the United States in the form of breaded seafood. The added value that local processing gives to the resource is determinant for obtaining higher prices, as compared to those being paid for squid as raw material, and for entering international markets for fi nished products. The proposed model covers the marketing plan, operations strategies and economic evaluation; the last one shows the economic results expected and the generated profi ts. The article ends by pointing out the critical factors of the business plan: the characteristics of the demand in the destination market and the supply of raw material.

Structure and Interaction of Protamine by Dark Field Electron Microscopy

1976 ◽  
Vol 34 ◽  
pp. 160-161
Author(s):  
D.P. Bazett-Jones ◽  
F.P. Ottensmeyer
Keyword(s):  
Electron Microscopy ◽  
Dark Field ◽  
Amino Acid Sequences ◽  
Dimensional Structure ◽  
3 Dimensional ◽  
Field Electron ◽  
Proposed Model ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Positively Charged

It has been shown for some time that it is possible to obtain images of small unstained proteins, with a resolution of approximately 5Å using dark field electron microscopy (1,2). Applying this technique, we have observed a uniformity in size and shape of the 2-dimensional images of pure specimens of fish protamines (salmon, herring (clupeine, Y-l) and rainbow trout (Salmo irideus)). On the basis of these images, a model for the 3-dimensional structure of the fish protamines has been proposed (2).The known amino acid sequences of fish protamines show stretches of positively charged arginines, separated by regions of neutral amino acids (3). The proposed model for protamine structure (2) consists of an irregular, right-handed helix with the segments of adjacent arginines forming the loops of the coil.

Tests und Tools

2007 ◽  
Vol 6 (2) ◽  
pp. 85-90 ◽  
Author(s):  
Rüdiger Hossiep ◽  
Sabine Bräutigam
Keyword(s):  
Integrity Test ◽  
Integrity Tests

Zusammenfassung. Vorgestellt wird das IBES (Inventar berufsbezogener Einstellungen und Selbsteinschätzungen), das erste publizierte deutschsprachige Verfahren der Gattung “Integrity Test”. Ziel des Instrumentes ist die Vorhersage kontraproduktiven Verhaltens in Unternehmen (z. B. Absentismus, Diebstahl, Aggression). Die Konstruktion erfolgte in enger Anlehnung an Inhalte prominenter amerikanischer Integrity Tests. Das IBES besteht aus einem einstellungsorientierten Teil mit 60 Items, die den vier Skalen “Vertrauen”, “Geringe Verbreitung unerwünschten Verhaltens”, “Nicht-Rationalisierung” und “Verhaltensabsichten” zugeordnet sind sowie einem eigenschaftsorientierten Teil mit 55 Items, unterteilt in die fünf Skalen “Gelassenheit/Selbstwertgefühl”, “Zuverlässigkeit/Voraussicht”, “Vorsicht”, “Zurückhaltung” und “Konfliktmeidung”. Die Anwendbarkeit des Verfahrens in der Praxis wird insbesondere vor dem Hintergrund der Datenbasis und des Itemmaterials kritisch diskutiert.

The Influence of Cognitive and Affective Reactions to Feedback on Subsequent Goals

2010 ◽  
Vol 15 (2) ◽  
pp. 121-131 ◽  
Author(s):  
Remus Ilies ◽  
Timothy A. Judge ◽  
David T. Wagner
Keyword(s):  
Performance Feedback ◽  
Business School ◽  
Structural Equation ◽  
Emotional Reactions ◽  
Equation Model ◽  
Proposed Model ◽  
And Performance ◽  
Dispositional Measure ◽  
The Relationship ◽  
Reactions To Feedback

This paper focuses on explaining how individuals set goals on multiple performance episodes, in the context of performance feedback comparing their performance on each episode with their respective goal. The proposed model was tested through a longitudinal study of 493 university students’ actual goals and performance on business school exams. Results of a structural equation model supported the proposed conceptual model in which self-efficacy and emotional reactions to feedback mediate the relationship between feedback and subsequent goals. In addition, as expected, participants’ standing on a dispositional measure of behavioral inhibition influenced the strength of their emotional reactions to negative feedback.

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