IMPLEMENTATION OF ARTIFICIAL NEURAL NETWORK IN CONCURRENCY CONTROL OF COMPUTER INTEGRATED MANUFACTURING(CIM) DATABASE

Abstract

Manufacturing database store large amount of interrelated data. The designers access specific information or group of information in the data. Each designer accessing an entity tries to modify the design parameters meeting the requirements of different customers. Sister concerns of the same group of company will be modifying the data as per design requirements. When information is updated with new modification by different group of designers, what is the order in which modification of the data has to be allowed. If simultaneous access of the information is done, how to maintain the consistency of the data. and a designer voluntarily corrupts the data, how to make sure the designer is responsible for the corruption of data. In any case if the transaction process corrupts the data, how to maintain the consistency of the data. Deleting the information wantedly can be identified with extra security for the data. However, when transaction protocol is not implemented properly, then corruption of data in the form of misleading information that showing less numerical value than what it has to be or showing more numerical than before updation. In this research work, we have proposed a neural network method for the managing the locks assigned to objects and the corresponding transactions are stored in a data structure. The main purpose of using the ANN is that it will require less memory in storing the lock information assigned to objects. We have attempted to use backpropagation algorithm for storing lock information when multi users are working on computer integrated manufacturing (CIM) database.

Full text

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P.Raviram & R.S.D.Wahidabanu

International Journal of Computer Science & Security, Volume (1) : Issue (5) 23
IMPLEMENTATION OF ARTIFICIAL NEURAL NETWORK IN
CONCURRENCY CONTROL OF COMPUTER INTEGRATED
MANUFACTURING(CIM) DATABASE
P. Raviram
Research Scholar/Department of Computer Science and Engineering
Vinayaka Mission’s University
Salem, 636 308, INDIA

R.S.D. Wahidabanu
Professor & Head
Department of Electronics and Communication Engineering
Government College of Engineering
Salem, 636 011, INDIA

ravirampedu@gmail.com
rsdwb@yahoo.com

ABSTRACT
Manufacturing database store large amount of interrelated data. The designers
access specific information or group of information in the data. Each designer
accessing an entity tries to modify the design parameters meeting the
requirements of different customers. Sister concerns of the same group of
company will be modifying the data as per design requirements. When
information is updated with new modification by different group of designers,
what is the order in which modification of the data has to be allowed. If
simultaneous access of the information is done, how to maintain the consistency
of the data. and a designer voluntarily corrupts the data, how to make sure the
designer is responsible for the corruption of data. In any case if the transaction
process corrupts the data, how to maintain the consistency of the data. Deleting
the information wantedly can be identified with extra security for the data.
However, when transaction protocol is not implemented properly, then corruption
of data in the form of misleading information that showing less numerical value
than what it has to be or showing more numerical than before updation. In this
research work, we have proposed a neural network method for the managing the
locks assigned to objects and the corresponding transactions are stored in a data
structure. The main purpose of using the ANN is that it will require less memory
in storing the lock information assigned to objects. We have attempted to use
backpropagation algorithm for storing lock information when multi users are
working on computer integrated manufacturing (CIM) database.
Keywords: Concurrency control, locks, backpropagation algorithm, neural network, CIM
database, Knowledge management.

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International Journal of Computer Science & Security, Volume (1) : Issue (5) 24
1. INTRODUCTION
Knowledge management in advanced database have been considered as an interesting research
area in the recent past. Real-Time database systems (RTDB) and Active database systems have
been discussed and implemented respectively to support non-traditional applications. Few
researches concentrate on the integration of active and real-time database systems and is very
much used in computer integrated manufacturing (CIM). New problems are evolved in
concurrency control (CC)[4,13] of real-time database systems. Conventional CC protocols are
more concerned about the serializability but real-time database systems also focus on transaction
deadlines. The situation is more complicated when real-time databases integrated with active
characteristic. RTDBs must not only respond to the external transactions but also the internal
triggered events. Due to the triggering structure in RTDBs, a dynamic CC algorithm is needed. If
we simply apply existing conventional database or real time database CC protocols, a lot of CPU
processing time will be wasted and transactions may not be able to complete before their
deadlines.
2. TRANSACTION PROCESS
Transaction is series of actions, carried out by user or application, which accesses or changes
contents of database. It is a logical unit of work on the database. It transforms database from one
consistent state to another, although consistency may be violated during transaction[2,3].
Concurrency is the process of managing simultaneous operations on the database without having
them interfere with one another. It prevents interference when two or more users are accessing
database simultaneously and atleast one is updating data. Although two transactions may be
correct in themselves, interleaving of operations may produce an incorrect result. Three potential
problems caused by concurrency are lost update, uncommitted dependency and inconsistent
analysis. Executions of transactions guaranteed to ensure consistency is identified by the concept
of serializability with those schedule of reads / write. Serial schedule is where operations of each
transaction are executed consecutively without any interleaved operations from other
transactions. Nonserial Schedule: Schedule where operations from set of concurrent transactions
are interleaved techniques used for concurrency Control are Locking and Timestamping. Both
are conservative approaches when delay transactions in case they conflict with other
transactions. Optimistic methods assume conflict is rare and only check for conflicts at commit.
Transaction uses locks to deny access to other transactions and so prevent incorrect updates. A
transaction must claim a shared (read) or exclusive (write) lock on a data item before read or
write. Lock prevents another transaction from modifying item or even reading it, in the case of a
write lock. Rules of locking are, if transaction has shared lock on item, can read but not update
item, and if transaction has exclusive lock on item, can both read and update item, Reads cannot
conflict, so more than one transaction can hold shared locks simultaneously on same item,
Exclusive lock gives transaction exclusive access to that item.

3. TRANSACTIONS REQUIREMENTS IN CAD DATABASE
Design and development of a product (shown in Figure 1) is the first and foremost step in a
manufacturing industry. This process is recurrent and repetitive until it reaches a final approved
design and development stage. Design and development activity involves defining and describing
the product, drawing the product in the computer using computer aided drafting(CAD) software
making modifications in the drawing, proving suitable material combinations for the product,
defining various sizes for the product, providing safety factor provision based on the end
application, satisfying customer requirements. The entire process will be generally interactive
between a designer and the customer with one to one direct contact, or interactive discussions
between designers at various locations, or independent design decisions by various designers
who are located at different places and are accessing the same database which is centralized
and sometimes distributed. When many designers are involved in designing an object in the
database a major problem of concurrency as well as version of the product developed occurs.

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Majority of transaction will be done with long time gap. In the existing commercial database, all
the equations and procedures are already coded with all the rules required which may change
time to time.[12] In such case, whenever a user is accessing the data in the form of read / write
the transaction quickly. He may not choose the choice of interest charged for the cash he swiped.
using his credit card. This indicates transaction with minimum amount of time.
Transaction with longer time period : In case of computer design process even though design
formulae have been encoded at the time of software development, the users will have their
choice of choosing their design requirements[1,2]. They will do design based on their previous
experiences and on the requirements of customers, based on the availability of machine
capabilities in the workshop. The activity of deciding the optimum design will take long time for
completing the transaction. Suppose, a similar design is done by another user very quickly, which
may be based on some criteria, the question is whether the second person can be permitted to
update the database or should he have to wait for the first person to the design process. What
type of transaction concept that has to be adopted is based on many criteria which may not be
readily fixed.
Controlling transaction with users choice: Most of the CAD transactions are based on
interaction among many users. Atleast two users would transact the knowledge, discuss and
come to a conclusion whether such design can be finalized. In such case, the final commit in the
database should be possible. This should not become impossible because of basic transaction
rules.
Cooperating the views of the designers in synchronization Many users working on shared
objects cannot be serialized. The shared objects shall pass among them when modifying two
parts of the same object parallelly to create new version of the object. In this case complete
serializability is not possible. New concept is being developed to meet maximum seriazability in
such type of shared interactive design environment.

4. EARLIER APPROACHES TO GROUP TRANSACTIONS
Developers of large project often work in small teams. A policy is to define the kinds of
interactions allowed among members of the same team as opposed to interactions between
teams. A group paradigm to deal with consistency of replicated data in an unreliable distributed
system[3]. We can hierarchically divide the problem of achieving serializability into two simpler
ones: (1) a local policy that ensures a total ordering of all transactions within a group; and (2) a
To CAM
process
Interface
algorithms
Definition of
geometric model
Definition
translator
Geometric
model
Design and
analysis algorithms
Drafting and
detailing
Documentation
Design
changes
FIGURE 1: Schematic diagram of Design and development.

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global policy that ensures correct serialization of all groups. Groups, like nested transactions, is
an aggregation of a set of transactions[5]. There are differences between groups and nested
transactions. A nested transaction is designed a priori in a structured manner as a single entity
that may invoke subtransactions, which may themselves invoke other subtransactions. Groups do
not have any a priori assigned structure and no predetermined precedence ordering imposed on
the execution of transactions within a group. Another difference is that the same concurrency
control policy is used to ensure synchronization among nested transactions at the root level and
within each nested transaction.. The group paradigm was introduced to model inter-site
consistency in a distributed database system. It can be used, to model teams of developers,
where each team is modeled as a group with a local concurrency control policy that supports
synergistic cooperation.

CAD Transactions in Groups : The group-oriented model does not use long-lived locks on
objects in the public database. The conversational transactions model sets long-lived locks on
objects that checked out from the public database until they are checked back into the public
database. The group-oriented model categorizes transactions into group transactions (GT) and
user transactions (UT). Any UT is a subtransaction of a GT. The model also provides primitives to
define groups of users with the intention of assigning each GT a user group. Each user group
develops a part of the project in a group database. A GT reserves objects from the public
database into the group database of the user group it was assigned. Within a group database,
individual designers create their own user database, and they invoke UTs to reserve objects from
the group database to their user database.

In the group-oriented model, user groups are isolated from each other. One user group cannot
see the work of another user group until the work is deposited in the public database. Group
transactions are thus serializable. Within a group transaction, several user transactions can run
concurrently. These transactions are serializable unless users intervene to make them cooperate
in a non-serializable schedule. The basic mechanism provided for relaxing serializability is a
version concept that allows parallel development (branching) and notification. Versions are
derived, deleted, and modified explicitly by a designer only after being locked in any one of a
range of lock modes.

The model supports five lock modes on a version of an object: (1) read-only, which makes a
version available only for reading; (2) read/derive, which allows multiple users to either read the
same version or derive a new version from it; (3) shared derivation, which allows the owner to
both read the version and derive a new version from it, while allowing parallel reads of the same
version and derivation of different new versions by other users; (4) exclusive derivation, which
allows the owner of the lock to read a version of an object and derive a new version, and allows
only parallel reads of the original version; and (5) exclusive lock, which allows the owner to read,
modify and derive a version, and allows no parallel operations on the locked version. Using these
lock modes, several designers can cooperate on developing the same design object. The
exclusive lock modes allow for isolation of development efforts (as in traditional transactions), if
that is what is needed. To guarantee consistency of the database, designers are only allowed to
access objects as part of a transaction. Each transaction in the group-oriented model is two-
phase, consisting of an acquire phase and a release phase. Locks can only be strengthened (i.e.,
converted into a more exclusive mode) in the acquire phase, and weakened (converted into a
more flexible lock) in the release phase. If a user requests a lock on a particular object and the
object is already locked with an incompatible lock, the request is rejected and the initiator of the
requesting transaction is informed of the rejection. This avoids the problem of deadlock, which is
caused by blocking transactions that request unavailable resources. The initiator of the
transaction is notified later when the object he requested becomes available for locking. In
addition to this flexible locking mechanism, the model provides a read operation that breaks any
lock by allowing a user to read any version, knowing that it might be about to be changed. This
operation provides the designer (more often a manager of a design effort) the ability to observe

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the progress of development of a design object, without affecting the designers doing the
development.

5. BACKPROPAGATION ALGORITHM (BPA)
An artificial neural network(ANN)[7] is an abstract simulation of a real nervous system that
contains a collection of neuron units, communicating with each other via axon connections. Such
a model bears a strong resemblance to axons and dendrites in a nervous system. Due to this
self-organizing and adaptive nature, the model offers potentially a new parallel processing
paradigm. This model could be more robust and user-friendly than the traditional approaches.
ANN can be viewed as computing elements, simulating the structure and function of the biological
neural network. These networks are expected to solve the problems, in a manner which is
different from conventional mapping. Neural networks are used to mimic the operational details of
the human brain in a computer. Neural networks are made of artificial ‘neurons’, which are
actually simplified versions of the natural neurons that occur in the human brain. It is hoped, that
it would be possible to replicate some of the desirable features of the human brain by
constructing networks that consist of a large number of neurons. A neural architecture (shown in
Figure 2) comprises massively parallel adaptive elements with interconnection networks, which
are structured hierarchically.
The BPA[6] uses the steepest-descent method to reach a global minimum. The number of layers
and number of nodes in the hidden layers are decided. The connections between nodes are
initialized with random weights. As shown in Table 1 a pattern from the training set is presented in
the input layer of the network and the error at the output layer is calculated. The error is
propagated backwards towards the input layer and the weights are updated. This procedure is
repeated for all the training patterns. At the end of each iteration, test patterns are presented to
ANN, and the classification performance of ANN is evaluated. Further training of ANN is
continued till the desired classification performance is reached.


FIGURE 2: Multilayer perception.
6. INTELLIGENT LOCKING STRATEGY PROPOSED LOCKING
IMPLEMENTATION
Inbuilt library functions for the bolt are available in standard CAD[8, 9,10,11, 12] softwares. In
Figure 3, the bolt and its entities are shown schematically. The bolt drawing (Figure 3) is used to
manufacture one variety of bolt that has to be used to clamp two plates. This drawing file will be
accessed by many designers who will choose their choice of designs and the designs are stored