Information System Analisis and Design

ERD initial image:
gambar-awal
ERD of the image above is less clear about the relationship between the entity the entity to the project, and I assume the relationship is 1 to N, where one section has many projects, and one project only owned one part only. Besides, from the ERD will be creating a new table is the table work. The table was because the relationship between the employee entity to which the project entitiy M to N, so create a new table.
a. 1NF normalization form of ERD from above:
gambar-fd1
Form above is a form of Normaslisasi 1NF. These fields obtained from the above attributes in the entity except KONTROLPEG field. Field is obtained from the relation of 1:1 entity employees and employees of entities to entities PART. Where a lot of employees to control personnel and an officer of the only controlled by an officer of the course. An employee can lead the section and led by only one employee only. FD is a functional attribute of Dependency where the arrow means that the attribute designated by the arrows, depending on the value of the attribute that points, for example, the attribute that points FD1 is NOPEG so that all attribute values are dependent upon the NOPEG.

b. 2NF normalization form:
1NF form from above and with Functional Dependency happens then obtained a second 2NF normalization form as follows
fd2

c. 3NF normalization form:
2NF form from above and with Functional Dependency happens then obtained a second form of 3NF normalization as follows
fd3

Normalization tech a lot of is utilized especially initiate because perspicuous and is applied.
Normalization basics
• form’s normal (normal form) are a braze from relationship database scheme that is defined for meeting aim of in height integrity and maintainability
• Kreasi of a normal form to be called normalization
Normalization reached by dependency analysing between each individual attribut that diassosiasikan with its relationship
Database design process (review)
1. Gather user needs / business
2. Develop a needs-based ER Model user / business
3. Convert E-R model to the set of relations (tables)
4. Normalization is to remove the anomaly relations
5. Implemented to create a database with a table for each relationship that is ter normalization

Database design process (review)
1. Normalization process is the establishment of the database structure so that most of the ambiguity can be removed.
2. Normalization stage, starting from the most mild (1NF) to most stringent (5NF)
3. Usually only up to the level of 3NF or BCNF because already sufficient to generate the table-a table of good quality.

Normalisasi Basis Data (2)
Why do normalization?
a. Optimizing table structures
b. Increase speed
c. The income data is the same
d. More efficient in the use of storage media
e. Reduce redundancy
f. Avoid anomalies (insertion anomalies, deletion anomalies, update anomalies).
g. Improved data integrity

Normalisasi Basis Data (3)
1. A table saying good (efficient) or if the normal 3 to meet the following criteria:
a. If there is decomposition (decomposition) table, it must be guaranteed safe dekomposisinya (Lossless-Join Decomposition). That is, after the table is described / in the decomposition into a new table-table, the table-table can generate a new table with the same exact.
b. Maintain dependence on the functional changes in data (Dependency preservation).
c. Does not violate Boyce-Code Normal Form (BCNF)
2. If the three criteria (BCNF) can not be met, then at least the table does not violate the Normal Form of the third stage (3rd Normal Form / 3NF).

Functional Dependency (1)
1. Functional Dependency describes a relationship attributes in relation
2. An attribute said functionally dependant on the other, if we use the value attribute to determine the value of the other attributes.
3. Symbol that is -> used to represent the functional dependency.
reads determine the functional

Functional Dependency (2)
1. Notasi: A à B
a. A and b is attribute of one table. Matter functionally A determines b or b cling to, if and only if available 2 data row with appreciative A same, therefore point b also with
2. Notasi: A à B atau A xà B
a. Are opposite of previous notation.

Functional Dependency (fd)
example :
untitled
a. Functional Dependency:
NRP à Nama
Mata_Kuliah, NRP à Nilai
b. Non Functional Dependency:
Mata_Kuliah à NRP
NRP à Nilai

Functional Dependency (4)
• Functional Dependency of point table
a. Nrp -> Name
Since for each point same Nrp, therefore Name point also with
b. {Mata_kuliah, NRP} -> Point
Since attribut Assesses to cling to Mata_kuliah and NRP IS ala goes together. In other mean for Mata_kuliah and same NRP, therefore Point also with, since Mata_kuliah and NRP constitutes to go to y. (get unique character).
c. Mata_kuliah -> NRP
d. NRP -> Point

First Normal Form – 1NF)
a. A relationship available in condition First Form’s Normal (1NF) if and only if all domain that implicated just consist atomic value, e.g. no group repeat (domain domain) in a tuple
b. Gain from 1NF appealed by Unnormalized Relation (UNRs) are on representasi’s moderation form and easy in development utilizes a query language
c. Its lack is requirement to data ‘s duplication
d. Largely relation systems (are not all) need a shaped deep relationship 1NF
A table on the form said to be normal if I did not reside in the unnormalized form of a table, where there is a kind of field multiplication and field that allows a null (empty)
Not allowed in there:
1. Many attributes of value (Multivalued attributes).
2. Attributes composite or a combination of both.
So:
1. Price is the domain attribute must be atomic rates

Example
For example College Student Data as follows:
kaka
Or
kaka1

Example (2)
Decomposition becomes:
a. College Student table:
kaka12
b. Hobby table:
kaka123

Second Normal Form – 2NF)
1. Normal form 2NF met in a table if it meets the form of 1NF, and all the attributes than the primary key, have a full Functional Dependency on primary key
2. A table does not meet 2NF, if there are attributes that ketergantungannya (Functional Dependency) are only partial (only depending on the part of the primary key)
3. If there are attributes that have no dependence on the primary key, then the attributes must be moved or removed
4. Functional Y is full if it is said to delete an attribute A from X -> dependency X means that Y is no longer dependent functional.
5. Y said if deleting a partial attribute A from X means that Y is functionally dependent.-> Functional dependency X
6. R depend on the full primary key fungsioanl R.Relation scheme R in the form 2NF if every non-primary key attribute A

Example
This following table accomplishes 1NF, but excluding 2NF

kaka1234
Example (2)

1. Does not meet 2NF, because (NIM, KodeMk) is regarded as the primary key:
NamaMhs -> (NIM, KodeMk)
Address -> (NIM, KodeMk)
Matakuliah -> (NIM, KodeMk)
SKS ->(NIM, KodeMk)
NilaiHuruf -> (NIM, KodeMk)
2. Table needs to be some table didekomposisi eligible 2NF

Example (3)
1. Functional dependencynya as follows:
NilaiHuruf (fd1) -> (NIM, KodeMk)
(NamaMhs, Address) (fd2) -> NIM
(Matakuliah, SKS) (fd3) -> KodeMk
2. So that:
Value Table -> fd1 (NIM, KodeMk, NilaiHuruf)
Table Student -> fd2 (NIM, NamaMhs, Address)
Table MataKuliah -> fd3 (KodeMk, Matakuliah, SKS)

(Third Normal Form – 3NF) (1)
1. Normal form 3NF fulfilled if the form meets 2NF, and if there are no non-primary key attribute that has a dependence on non-primary key attributes of the other (transitive dependencies).

Example (1)
1. Table following students eligible 2NF, 3NF, but does not meet
kaka12345
2. Because there are non-primary key attribute (ie, City and Provincial), which has a dependence on non-primary key attributes of the other (ie KodePos):
(City, Province)KodePos

Example (2)
1. So that the table in the decomposition needs to be:
2. Student (NIM, NamaMhs, Road, KodePos)
KodePos (KodePos, Province, City)

Boyce-Codd Normal Form (BNCF)
1. Boyce-Codd Normal Form constraint has a stronger form of the Normal third. To be BNCF, relations must be in the form of Normal Kesatu and forced each of the attributes depends on the function in the super key attributes.
2. In the example below there is a relationship seminar, is the Primary Key NPM + Seminar.
Students may take one or two seminars. Each seminar requires 2 each of the students and led by one of the 2 seminar. Each leader can only take one seminar course. NPM in this example and show a Seminar Counsellor

Boyce-Codd Normal Form (BNCF)
kaka123456
Seminar Relationship form is shaped Normal drd, but don’t BCNF
since seminar Code is still hinge function on Counsellor, if each Counsellor gets to teach just one seminar. Dependent seminar on one attribute is not super goes to y. as one at presupposes by BCNF. Therefore
seminar relationship shall be broken down as two which is:
kaka1234567
Normal form of the fourth and fifth
1. Relations in the fourth normal form (NF 4) if the relation in BCNF and dependency tdak contain many values. To remove the dependency of many values from a relation, we divide the relationship into two new relations. Each relation contains two attributes that have a lot of relationship value.
2. Relations in fifth normal form (5NF) deal with the property called the join without any loss of information (lossless join). Fifth normal form (also called the 5 NF PJNF (projection join normal form). The case is very rare and appear difficult to detect in practice.

DEFINITION BASIS DATA
1. The Definition of databases:
a. A group of data file in disk magnetic, optical disk or depository of other sekunder
b. Inwrought collection of datas which each other is interconnected the than an enterprise ( company, government institution or private sector )
1. Manufacturing business -> planning data production, acctual data production, data ordering of material, etc
2. Hospital -> data of patient, doctor, nurse, etc

DATABASE MANAGEMENT SYSTEM
1. Corps or database aliance with software application being based on database
2. This programs application is used to access and maintenance of database
3. Especial target of DBMS is provide an efficient and easy environment for the usage of, withdraw and depository of data and information

BIT, BYTE, FIELD
1. Bit -> the representing part of containing smallest data of value 0 or 1
2. Byte -> the collection of bits which of a kind
3. Field -> a group of byte-byte which of a kind, in databases used by attribute term

ATRIBUT/FIELD
1. The Representing of nature or characteristic from an entitas providing to detail of clarification about entitas
2. An relationship can also have attribute
The Example of Attribute :
a) STUDENT: NIM, NAME, ADDRESS
b) CAR: PLATENUMBER, COLOUR, TYPE, CC

ATRIBUT TYPES
1. Single vs multivalue
Single -> just can fill at most one value
Multivalue -> can fill with interest from one value with same type
2. Atomic vs komposisi
Atomic -> indiscrete into smaller attribute
Composition -> the representing aliance from some smaller attribute

ATRIBUT TYPES (2)
1. Derived Attribute
The attribute which is value can be yielded from other attribute value, for example -> yielded age of attribute of birthdate
2. Null Value Attribute
The attribute which don’t have value to an record
3. Mandatory Value Attribute
The attribute which must have value

RECORD/TUPLE
1. Representing an data line in a certain relationship
2. The Consist of attributes corps where attributes of interaction to inform entitas / relationship completely

ENTITAS/FILE
1. File is represent colection of record which of a kind and have same element, the same attribute but different each other its data of him.
2. Type File
3. In application process, file can be categorized as follows:
a) File Mains
b) File Transaction
c) File Report
d) File History
e) File Protector
f) File Job

DOMAIN
The Domain represent collection of values enabled to stay in one or more attribute. Every attribute in once databases of relasional defined by an domain

DATA ELEMENT KEY
Key is element of record weared to find the record when accessing or can also used to identify every entity/record/baris.

1. Superkey represent one or more attribute from an table of able to be used to identify entityty / record of tables uniquely ( don’t all attribute can become superkey)
2. Cadidate Key is super key with minimum attribute. Candidate key may not contain attribute of other tables so that key candidate beyond question superkey but not yet of course on the contrary.
3. Primary Key
One of the attribute of key candidate can be selected / determined to become primary key with three criterion as follow:
1. The Key more natural to used as reference
2. The Key more simple
3. The Key well guaranted him

a) Alternate Key is attribute of key candidate which is not chosen become primary key.
b) Foreign Key represent any attribute subjecting to key primary at other tables.
c) Foreign key will happened at one particular relationship owning one to many kardinalitas ( one to many) or many to many ( many to many). Foreign key usually always put down at tables of which is flange to many.
d) External Key represent an attribute lexical ( or gathering of lexical attribute) which is values always identify one object of instance

ERD (ENTITY RELATIONSHIP DIAGRAM)
1. ERD is a network model using wording which is kept in system abstractionly.
2. Difference between DFD and ERD :
a) DFD represent a function network model to be executed by system
b) ERD represent data network model emphasizing at and structure of data relationship

ELEMEN IN ERD
1. ENTITY
At ER Diagram of Entity depicted with square form of length. entity is something that there is in real system and also abstraction where on file data or where there are data.
2. Relationship
At ER relationship Diagram can be depicted with a lozenged. Relationship is natural relation that happened between entitas. Is general called with elementary vb. so that facilitate to read of relationship.
3. Relationship Degree
Relationship Degree is the amount of entitas participating in one relationship. Degree of which is often weared in ERD.
4. Attribute
Attribute is the nature or characteristic of each and also entitas of relationship
5. Kardinalitas showing optimum of tupel able to relate to entitas at other entitas
Derajat relationship
1. Unary Relationship is model of relationship that happened between entity coming from entity same.
2. Binary Relationship is model of relationship that happened between 2 entitas..
3. Ternary Relationship Representing relationship between instance from 3 type of entitas unilaterally

KARDINALITAS
Available 3 cardinalities relationships which is
1. One to One : Relation storey level one to one expressed with one occurence at first entitas, only having one relation with one occurence at second entitas conversely.
2. One to Many atau Many to One : Subjective zoom one to there are many is same with many to one pending of tenor which that relationship is seen. To one instance on entities first gets to have many relationship with instance on entities secondly, if contrariwise one instance on entities just secondly gets to have connection with one instance on entities is first.
3. Many To Many : Happening if each event on one entities has a many relationship with event on another entities.

NOTATION IN ER-DIAGRAM
Symbolic notation diagrammatically ER is
1. Length square declare for entities gathering
2. Circle declares for attribute
3. Explain rhomb relationship gathering
4. Lining as connecting as among relationship gathering with entities gathering and
5. Entities Gathering with its attribute

FLOWCHART
Flowchat is reffered also Data of Flow Diagram (DFD)
Depicting the division of system into smaller module
Facilitating less comprehending user of computer area to understand system to be done

KONTEXT DIAGRAM
1. Consist of once process and depict scope from a system
2. Representing highest level of DFD depicting all input to system and output of system
3. System limited by boundary ( depicted by dash line)
4. There may not be any is depository ( storage)

ZERO DIAGRAM
• Depicting process of DFD
• Opening on to by totally regarding system handled, showing existing especial process or function, data stream and of eskternal entity
• At this level is enabled by the existence of data of storage
• For process which is not detailed again at level hereinafter hence enhanced by symbol ‘*’ or ‘ P’ by the end of process number
• Input balance and of output ( balancing) between diagram 0 with context diagram have to be looked after

DETAIL DIAGRAM
• Representing diagram elaborating process what there [is] in diagram zero or level above him
• Level Numberization at DFD:

. In one level shall not there are more than 7 process and maximal 9, when more hence must be done decomposition.

THE SPECIFICATION OF SYSTEM
• Every process of DFD have to the specification of process
• At method level top used to depict process earn by using descriptive sentence
• At more level detailed that is at process most under ( primitive functional) requiring the specification of more the structure
• Specification of process will become guidance to programmer in making program ( coding)
• Method which is used in specification of process: breakdown of process in the form of story, decision table, decision tree

EXTERNAL UNITY.
• Something that beyond system, but he give data into system or give data of system
• Symbol with notation box
• External of entity doesn’t the including the part of system

CURRENT DATA
• Representing place emit a stream of information him
• Depicted with connective straight line component of system
• Data current shown with direction bow and line called of data current emiting a stream of
• Data current emit a stream of among process, data of storage and show data current of data which in the form of input for system
• Guidance gift of name:
• Name of data stream which consist of some word stream attributed to continued line
• There may not be any data stream which is same name and gift of name have to express its contents
• Data stream which consist of some element can be expressed with element grup
• Avoid usage of word ‘ data’ and ‘ information’ to give the name of data stream
• As possible the name of data stream written is complete
• Other of rule:
• Name of data stream which come into an process may not is equal to name of secretory data stream of process
• data of Flow which step into or go out from data of storage needn’t be called if:
• comprehended easy and simple Data stream
• Data stream depict all data item
• There may not be any data stream of terminal to data of storage or on the contrary because terminal non part of system, terminal link with data of storage have to through process

PROCESS
• Process represent what done by system
• Process can be procesing data stream or data enter to become exit data stream
• Functioning process of transformation one or some input data become one or some output data as according to specification of which is wanted
• Every process have one or some input and also yield one or some output
• Process often is also referred as by bubble
• Guidance gift of process name:
• The name of process consist of noun and vb. expressing process function him
• Don’T use word process as part of the name of a bubble
• There may not be any some process owning the name of is same
• Process have to give by number. Number sequence as possible follow process sequence or stream, but that way meaningless number sequence absolutely represent sequence process chronologically

STORAGE DATA
• Data of Storage represent existing data repository in system
• The symbol with a couple of parallel line or two line wrongly one side from other side openly
• Process can take data from or give data to database
• Guidance gift of name:
• Name have to express data of storage
• When its name more than one word hence have to say the word to joint

DFD SYMBOL

DATA DICTIONARY
• Function to assist perpetrator of system to interpret application in detail and organizational all used by data element is system precisely so that user and system analyst have is same congeniality base about input, output, depository and process
• At analysis phase, data dictionary used as by communication means among system analyst with user
• At phase scheme of system, data dictionary used to design input, database and report
• Data current at DAD have the character of globally, boldness more detailed can be seen by data dictionary
• Data dictionary load the followings:
• Name of data current: have to be noted reader to needing furthermore clarification about a data current can look for it easily
• The other name: name or other name of is differ from data can be written by if there are any
• Data form: used to group data dictionary into its use time scheme of system
• Data current: showing where from data emit a stream of and where data go to
• Clarification: giving clarification about meaning of data current

BALANCING TO DFD
• Data stream which come into and go out from one process have to is equal to data stream which come into and go out from detail of process at level/ level under him
• Name of data stream which come into and go out from one process have to is equal to name of data stream which enter into and go out from detail of process
• Amount and name of entitas external from an process have to is equal to name and amount of entitas external from detail of process
• Things which must be gave attention to DFD owning more than one level:
• Have to there are input balance and of output among one and level of level next
• Balance among level 0 and level 1 seen at input and output of data stream to or from terminal at level 0, while balance among level 1 and level 2 seen at input / output of data stream to / from pertinent process
• Name of data stream, data of storage terminal and at every level have to be is same if its same object

PROHIBITION ORDER IN DFD
• Data current may not from direct external entitas go to other external entitas without passing an process
• Data current may not from direct data deposit go to external entitas without passing a process
• Data current may not from direct data deposit go to other data deposit without passing a process
• Data current from one direct process go to other process without passing an data deposit better / can is possible avoided

PERCEPTION EARLY , REQUIREMENT OF ANALYSIS
CONCEPT of SYSTEM INVESTIGATION
Gap between target of system condition and system in fact
Report detect problem don’t really real
a. Target too ideal
b. Lacking of resource and or attitude
c. Measurement of system less accurate
d. Target of system which have under developed
e. The difference between system of ideal system and whereas
CONCEPT SYSTEM OF INVESTIGATION
Solving Problem:
Formulation of system which is walking -> detail in investigation
Getting ideal system consensus
Developing some alternative
Choissening best alternative
Target of investigation -> showing the problem of which in fact happened
CONSTRAINT IN INVESTIGATION SYSTEM
The investigation of some constraint which is often emerge :
a. Time
b. Expense
c. Science
d. Politic
e. Interference
RECOMENDATION
The result from investigation is a containing recommendation, for example :
Don’t bring an action against anything -> problem not found
The conservancy of system -> problem of small
Improving ability or skill of user
The system Considering modification totally
Placing the problem that happened into system development plan which is immediately
TACTIC INVESTIGATION
Why needed tactics?
Finding all problems
Knowing cause of appearance is problem
Determining correct solution
Conducted so that all system element can accept offer of solution without bothering their activity
Some tactics able to be conducted :
Listening opinion from perpetrator of system
Don’t give resolving early
Comparing story some people perpetrator of system to same case
Paying attention the problem of logical inkonsistency
Direct:
Quesioner
Question And Answer
Perception
Indirect:
Stream Procedure
Studying document
Sample
Tabular
DESCRIPTION OF SYSTEM
Input
Output
File
Data element
Volume Transaction and action document
Data flowchart
The intensive Interaction phase between system analyst with user end where system development team show its membership to get comments and trust of user so that get good participation

4 TARGET OF WHICH WISH TO BE REACHED
Explaining system completely
Depicting ideal information system
Bringing ideal information system to condition in this time by paying attention resource constraint
Giving motivation to confidence of user into system development
Method
Question And Answer
Kueisioner
Observation
Procedure Analysis
Perception of document
CONSTRAINT RESOURCE
Time
Money
Membership
Technological
Factor of eksternal
The Document requirement of analysis
Analysis instruction : Relation with final user, perception of process, problem of data collecting
Requirement of User : Requirement in fact, Requirement of report, requirement of training and influence of new system
Constraint System : Explaining time constraint and expense, membership, technological and factor of eksternal
The Document in the form of data collecting instrument, statistical consensus, data stream by logical and physical, data element early in data dictionary.
How to draw near the condition of system in this time with condition of ideal system?
Make alternative to solve problem information system
the Best alternative applied wisely
Choice Strategy
Distributed Versus processing centralized
Change of decision of information of data centralized of processing to center responsibility user end decentralized
Database dispersed versus Integrated
Designer of system should to consider data any kind of which into databases and which come into file
Surround Strategy of System Development
Environmental around important strategy in the case of confiscation because information system of other company possible differ from company in this time.
Choice Tactics
Conducted before choice scheme of operational
Choice Scheme of Operational
Choice Scheme can be grouped into
Input
Online Vs Off Line Data Entry
Keyed Vs Machine Readable Data Entry
Centralized Vs Decentralized Data Entry
Processing
Batch of Vs Real time update record
Sequential Vs Direct Access records to
Single Vs Multiple User update records of
Output
Traditional Vs Turn Around Documents
Structured Vs Inquiry reports based
The compare tactics: System compared to pursuant to advantage and expense relatively;
There is three way of system of A told more pre-eminent with other system if:
A have lower expense of B and advantage both is same
A have lower expense of B and of A yield advantage which more than B
A and of B have same expense but yielded advantage is A more.
Some Method of Comparasy system
Break Even Analyisis point
Payback Period
Discounted Payback period
Internal Rate Of Return
Category of Expense
Hardware
Software
People
Suppliers
Telecommunications
Physical Sites
Detail of Expense
Comparing the expense of information system pass life of system, projection analyst how many change of expense for the future and there three model of expense of information system that is Linear, Eksponensial and Step Function
Expense of information system earn just happened once and earn also happened chronically.
Expense of just information system that happened once that is cost on times and of development cost that happened system development moment.
Expense of information system that happened continually among others is cost reccuring and also cost operational where this expense happened information system moment operate every day.
Factor Qualitative which is good information system performance flange among others
Lessening mistake storey
Lessening time to improve repair mistake
Lessening time listen carefully from alternative workstation
Quickening ready time of information
Improving system security
Multiply update is source of active record
Improving satisfaction of wearer

FACTOR STRATEGY COMPANY
Satisfaction of consumer
Mount sale
Consumer commitment and of vendor
Information product marketing
The presentation in a word
Lessening clarification of technique in detail
The representations clearly by means of assist visually
If using model use appliance assist for example laptop so that more informative
Emphasizing advantage of information system proposal with a few existing alternative according to condition of natural by company.
If company set mind on to develop system hence information department will process hereinafter that is Process of Design System.
If on the contrary hence System Development Life Cycle ( SDLC) will be discontinued
Frequently will be found the problem of with study system and usually management top will ask of reworking to study system. Model will explain repeated step some part and sometime information department will make decision to repeat step before explaining study system. With alternative, decision to repeat a step of SDLC not to speak of or previous Go – No – Go Decision

Existence of problems that appear in system old ones. Problems of arising out such of

a. Existence of Problems (Problems)

Disability of old system in solving problem and didn’t work as the expected until information system needed..

b. Annoyance in Growth’s system of Organization

The big need and request about information, the increase of data tabulation volume and the change of new accounting principle causes old system not capable and effective anymore, so we need to make the information system.

c. For reach the opportunities ( opportunities )

d. Existence of instructions ( directives)

The Compilation of new system can also happened caused by instruction – instruction from the leader or from outside organization, for example regulation of government.

There are the purposes of development of information system.

a. Solving problems

By the information system, problem of disability of old system in solving problem will be finished..

b. Reach for opportunities

c. Fulfill the instruction that given

There are the expectations of organization after executing the information system

a. Performance ( performance)

Measured to use and throughput of response time. By the performance information system from a organization will mount progressively and more effective.

b. Information ( information)

increase the quality of information.

By the information system, presentation of message or information from an organization will progressively mount

c. Economy ( economic)

increase the benefit of vs decreasing cost. By the information system, make-up of benefits will mount progressively . And expense which needed can be depressed or lessened.

d. Control ( operation)

Detecting and improve the mistake.

e. Efficiency ( efficiency)

Efficient of operational.

f. Services ( service)

Increase the service of system.

There are some principles of system development of information

a. System for the management

b. System is a big investment

Investigation of all alternative ( minimizing missing cost opportunity). Best investigation have to be valuable : analysis cost-benefit & analysis cost-effectivines

b. System need educated people

The system need people that professional on each department, not ought to have the high education, the important think that people must really professional on the department that they handle.

c. Step work -> System cycle life development

d. System development do not have to numbering

e. Don’t fear to cancel project

f. System documentation

Three cycle live development of system are

a. Model of Waterfall

Waterfall_model

The waterfall model is a popular version of the systems development life cycle model for software engineering. Often considered the classic approach to the systems development life cycle, the waterfall model describes a development method that is linear and sequential. Waterfall development has distinct goals for each phase of development. Imagine a waterfall on the cliff of a steep mountain. Once the water has flowed over the edge of the cliff and has begun its journey down the side of the mountain, it cannot turn back. It is the same with waterfall development. Once a phase of development is completed, the development proceeds to the next phase and there is no turning back

Initiation/Planning

To generate a high-level view of the intended project and determine the goals of the project. The feasibility study is sometimes used to present the project to upper management in an attempt to gain funding. Projects are typically evaluated in three areas of feasibility: economical, operational, and technical. Furthermore, it is also used as a reference to keep the project on track and to evaluate the progress of the MIS team.[6] The MIS is also a complement of those phases. This phase is also called the analysis phase.

Requirements Gatherings And Analysis

The goal of systems analysis is to determine where the problem is in attempt to fix the system. This step involves breaking down the system in different pieces and drawing diagrams to analyze the situation. Analysts project goals, breaking down functions that need to be created, and attempt to engage users so that definite requirements can be defined.

Design

In systems design functions and operations are described in detail, including screen layouts, business rules, process diagrams and other documentation. The output of this stage will describe the new system as a collection of modules or subsystems.

Build or Coding

Modular and subsystem programming code will be accomplished during this stage. Unit testing and module testing are done in this stage by the developers. This stage is intermingled with the next in that individual modules will need testing before integration to the main project. Planning in software life cycle involves setting goals, defining targets, establishing schedules, and estimating budgets for an entire software project

Testing

The code is tested at various levels in software testing. Unit, system and user acceptance testing are often performed. This is a grey area as many different opinions exist as to what the stages of testing are and how much if any iteration occurs. Iteration is not generally part of the waterfall model, but usually some occurs at this stage.

Types of testing:

Data set testing

Unit testing

System testing

Integration testing

Black box testing

White box testing

Module testing

Regression testing

Automation testing

User acceptance testing

Operations and Maintenance

The deployment of the system includes changes and enhancements before the decommissioning or sunset of the system. Maintaining the system is an important aspect of SDLC. As key personnel change positions in the organization, new changes will be implemented, which will require system updates.

The advantage of waterfall development is that it allows for departmentalization and managerial control. A schedule can be set with deadlines for each stage of development and a product can proceed through the development process like a car in a carwash, and theoretically, be delivered on time. Development moves from concept, through design, implementation, testing, installation, troubleshooting, and ends up at operation and maintenance. Each phase of development proceeds in strict order, without any overlapping or iterative steps.

b. Model Iterative

Iterative_development_model_V2

In computer programming, iterative is used to describe a situation in which a sequence of instructions can be executed multiple times. One pass through the sequence is called an iteration. If the sequence of instructions is executed repeatedly, it is called a loop, and we say that the computer iterates through the loop.

In software development, iterative is used to describe a heuristic planning and development process where an application is developed in small sections called iterations. Each iteration is reviewed and critiqued by the software team and potential end-users; insights gained from the critique of an iteration are used to determine the next step in development. Data models or sequence diagrams, which are often used to map out iterations, keep track of what has been tried, approved, or discarded, and eventually serve as a kind of blueprint for the final product.

The challenge in iterative development is to make sure all the iterations are compatible. As each new iteration is approved, developers may employ a technique known as backwards engineering, which is a systematic review and check procedure to make sure each new iteration is compatible with previous ones. The advantage of using iterative development is that the end-user is involved in the development process. Instead of waiting until the application is a final product, when it may not be possible to make changes easily, problems are identified and solved at each stage of development. Iterative development is sometimes called circular or evolutionary development.

c. Model Spiral

Spiral_model_(Boehm,_1988)

The spiral model, also known as the spiral lifecycle model, is a systems development lifecycle (SDLC) model used in information technology (IT). This model of development combines the features of the prototyping model and the waterfall model. The spiral model is favored for large, expensive, and complicated projects.

The steps in the spiral model can be generalized as follows:

1. The new system requirements are defined in as much detail as possible. This usually involves interviewing a number of users representing all the external or internal users and other aspects of the existing system.

2. A preliminary design is created for the new system.

3. A first prototype of the new system is constructed from the preliminary design. This is usually a scaled-down system, and represents an approximation of the characteristics of the final product.

4. A second prototype is evolved by a fourfold procedure: (1) evaluating the first prototype in terms of its strengths, weaknesses, and risks; (2) defining the requirements of the second prototype; (3) planning and designing the second prototype; (4) constructing and testing the second prototype.

5. At the customer’s option, the entire project can be aborted if the risk is deemed too great. Risk factors might involve development cost overruns, operating-cost miscalculation, or any other factor that could, in the customer’s judgment, result in a less-than-satisfactory final product.

6. The existing prototype is evaluated in the same manner as was the previous prototype, and, if necessary, another prototype is developed from it according to the fourfold procedure outlined above.

7. The preceding steps are iterated until the customer is satisfied that the refined prototype represents the final product desired.

8. The final system is constructed, based on the refined prototype.

9. The final system is thoroughly evaluated and tested. Routine maintenance is carried out on a continuing basis to prevent large-scale failures and to minimize downtime.

There are the approve of development a system.

a. Classic approach vs approach of structure

Classic approach represent opponent from approach of structure.

Classic approach

Classic approach can also traditional approach or conventional approach.

a) Steps in SDLC

b) Do not involve consumer, for emphasizing the system analyst

c) Problems: difficult development, expense of costly treatment, possibility of big mistake, efficacy less well guaranted, applying internal issue

Approach of structure

a) Consumer involve from early to determine the requirement of system

b) Using tools-tools like data of flow diagram

b. Approach of rasher of vs approach of system

Approach of rasher

a) Emphasizing at an activity or application

b) Heedless of entirety target

Approach of system

a) See system as one intact unity

b) Emphasizing at goal achievement as a whole

c. Approach of bottom-up vs approach of top-down

Approach of bottom-up

a) Started from level under that is operational

b) Representing classic approach marking

c) Recognized with term of data-analysis

Approach of top-down

a) Started from up level that is planning of strategy

b) Representing marking approach of restructure

c) Recognized also with decision-analysis

d. Approach of vs whole system vs approach of modular

Approach of whole system

a) Developing system at a time and totally

b) Representing classic approach marking

Approach of modular

a) Breaking complicated system become the parts of simple

b) Developed system become timely, easy to be comprehended and looked after

c) Representing marking approach of structure

e. Approach of great loop approach vs expand

Approach of ( approach great-loop )

a) Developing system at a time use sophisticated technology

b) High risk and finish many expense

Approach expand ( approach evolutionary)

a) Applying sophisticated technology for certain applications

b) Developed to follow requirement

c) Cost effective and can keep abreast of technology

There are the congeniality of methodology, method, and algorithm

a. Methodologies is the Methods which is used in science. Methodologies is unity of method – method, procedure – procedure, concept – conception work, order – postulate and order – postulate used an science, artistic or the other discipline.

b. Method is a way of systematic to do something.

c. Algorithm is procedure sequence to solve a problem

There are the Clarification of three classification of methodology development of system

a. Decomposition Functional

Emphasizing resolving of system become sub system

Example : HIPO, Stepwise Refinement, refinement stepwise iterative, hiding information

b. Data-Oriented

Emphasizing at processed data characteristic

a) Oriented Data-flow: modules according to data element type

b) Oriented Data-structure: input structure and of output

c. Prescriptive

usually provided by factory maker of software

There are the appliance – appliance used to develop a system

a. In form of graph: HIPO, SADT, Jackson’s Diagram, and others

b. Appliance using schema

a) Charting Activity: depicting activity, example of: Chart Gant, flowchart, etc

b) Charting Layout: depicting the place of system

c) Relationship charting Personal: depicting personnel , example : chart organization, chart distribution working

There are the technique – used technique in developing a system

a. Management technique of project for schedule of project , example : CPM and of PERT

b. Technique find fact to collect and determine data / fact 1. Interview 2. Observation

c. Technique analyse expense / benefit of cost-benefit and cost-effectiveness analysis

d. Technique to do the meeting

e. Inspection technique

The Difference of system’s analyst and a programmer

a. System analyst: studying problems and determine requirement of system to identify resolving

b. Programmer: writing program code pursuant the design made by analyst

System analyst undertake to link difference of knowledge that happened between system’s analyst and system of programmer

There are the Knowledge that used an analyst system to influence a system

a. Data-Processing technology, and computer of programming

b. Knowledge of business in general

c. Quantitative method: regretion, linear programming, etc

d. Skill of trouble-shooting

e. Skill of communications between personnel

f. Skill to construct relation between personnel

There are two approach used to define a system, that is  approach.
Prosedure : “a system is a network work from procedures which is relation each other , gatherin  together to do  an activity  to finish a certain target.”
Procedure is a combination of klerikal’s operation ( writing), that entangling some people in one more departmental used to guarantee a some handing from bussines transactions that happened to finish a certain activity. Activity sequence used to explain “what” which must be done, “who” is  doing it,  “when” be done and “how” to do it.
the Emphasis of element ” System is corps of elements which is have interaction to reach specific-purpose
Both definition is correct and doesn’t  interfering each other, the different is the way of its approach. Approach of system representing corps of elements or components of sub systems represent broader definition. This definition more accepted, because in reality a system can consist of some  sub system or  part’s systems. For example accounting system can consist of some subsystems, that is sale accountancy sub system, purchasing accountancy sub system, remuneration accountancy sub system, cost accounting subsystem etc.

The Charactheristic Of System
A system has characteristic or certain nature that is :
a. Components
Consist of a number of component which interact, and cooperate to form one unity. the component can consist of some subsystem or subpart, where each subsystem have special function and will influence system process as a whole.
b. Input
The Energy entered into system. Input can be the treatment input ( input maintenance) and input of signal ( input signal).be the example of in computer system, treatment input is a programe, input of signal is a data.
c. Output
The Result of energy is processed and classified to be output which usefull  and rest of dismissal. Example of the system of computer,  the hot that yielded is the rest of dismissal, while information is output which good for
d. Process
A system can have a part of processor to change input become output. For Example of accounting system will process transaction datas become monetary a reports and other reports which required by management.
e. Objectives or Goal
A system sure has a target. The target of system very determine once required by input system and output to be yielded by system. goal cover  wide of scope, while objectives cover narrow tight scope.

The Classification Of System

a. Deterministic System
The Certain system operate with behaviour which have earned can be predicted, interaction between its sharess can be detected categorically so that its output can be forecasted. for example of : Computer programe, executing precisely as according to its instruction network. System of pay, and others.
b. Probabilistic System
The System which is input and its process can be defined, but yielded output cannot be determined categorically; ( always there is a little mistake / deviation to forecast of the way system). for Example : marketing system)
c. Open System
The system that relation and effect external environment .This system accept input and yield output for external environment / the other sub system, so that have good operation system. This system tend to measure up to adaptation, can adapt to its environment so that can continue its.
d. Closed System
The System Physical where the process that happened do not experience of transfer of items, information or energy with environment outside system. This system work automatically without existence of interfere in of external side of it.
e. Relatively Closed System
The closed System but doesn’t closed at all to accept other influences. This system in its operation can accept influence from outside which have been defined in certain boundarys.
f. Artificial System
The System imitating occurence in system. This system is formed pursuant to occurence in nature where human being unable to do it. Equally imitat exist in nature.
g. Natural System
The natural  System is occurence in nature. for Example of : sea, solar system and others.
h. Manned System
The System explanations of behaviour covering human being taking part in. This system can be depicted in way of as follows:
The System of Human being focus the relations between human being
The System of Human being – Machine, System which involve machine to a target
The Machine System, automatic system where human being have duty to start and finish system, meanwhile human being entangled also to monitor system.


  • None
  • No comments yet

Categories