Wednesday, 9 November 2016

Project Management | Definition of project | Definition of Project Management | Problems in Software Projects

Project

The fundamental nature of a project is that it is a “temporary endeavor undertaken to create a unique product, service, or result
                                                  Project management

Project management is the process of the application of knowledge, skills, tools, and techniques to project activities to meet project requirements.” That is, project management is an interrelated group of processes that enables the project team to achieve a successful project. These processes manage inputs to and produce outputs from specific activities; the progression from input to output is the nucleus of project management and requires integration and iteration.

problems in Software Projects

Software projects are similar to traditional projects in the sense that the same
types of problems affect them both. However, the difference in managing these
problems lies in the approach that you take to the specific issue. For example, a
technology-related problem for a software project might be the low degree of
reuse of the software components created. However, for a car-manufacturing firm,
there is no chance of reusing a component such as a front axle

People-related problems

Process-related problems

Product-related problems


People-related problems

Low motivation: As the project manager it is your responsibility to ensure an
optimal level of motivation within the team. Lengthy projects, complex activitiesand scarce resources often decrease the motivation level in a
software development team. However, you need to lead in such a way that the
team is constantly motivated to do a good job

Problem employees: Some members of any team always create a problem.  Problem
employees raise the chances of conflicts and differences of opinions within
the development team. They lower the efficiency and productivity of other
team members and make it difficult to meet the objectives of the software
project within the specified time. You need to ensure that employees are not
allowed to create a problem for the rest of the team


Lack of stakeholder interest: For a software project to be a success, each
stakeholder needs to take an active interest in the progress of the project. Al1
stakeholders, including the customer, the management, and the software
development team, need to commit to the success of the project. For example,
if the software development team is not committed to the project, then their
contribution may not be to the optimum level

Process- related Problems

Unrealistic schedule: Assigning unrealistic deadlines for a software project is
a primary reason why software projects are delayed. Often, the marketing or
the management team commit a delivery date to the customer in the hope of
getting the project contract. However, these dates are not decided in
consultation with the development team. The rationale for assigning the
deadlines is unfounded. You need to ensure that the deadlines match the
ability of the software team to deliver the software product. 
.
·
Insufficient identification: Unidentified, partially identified, and unplanned
risks pose a threat to the success of a software project. You need to intensively
identify risks and evolve a risk management plan such that the project is
completed successfully, on time

unsuitable life cycle model selection: Different software projects require
different SDLC models. For example, a project to create banking .software is
different from software for a satellite where the concept needs to be
researched. For the former example, the Waterfall model is more applicable.
For the latter example, the Spiral model is more suitable. Selecting the correct
life cycle model is critical to the success of a software project.

Product-related Problems

Product scope changed toward the end of the project life cycle: The project
time, effort, and cost estimates for a software project can go up dramatically
when the customer changes the scope 9f the product toward the end of the
project. In such situations, you should verify the criticality of the scope
change. However, if the change request is not critical, you should retain the
original scope with a proper explanation to the customer. If the change request
is critical, you should explain the situation to the customer. Usually, a
customer gives more time and funds to a software project if proper
justification is provided. In some cases, the scope change may also be because
of a change in government policy. It may become mandatory for you to
include such change requests.
·
Research-oriented software development: Many software projects digress
from the original scope because of the nature of the software product or
technology used. When a totally new kind of software is developed 
or a new technology is used, the software development team can lose focus of the
objectives by getting into a research-oriented approach. It becomes your
responsibility as the project manager to maintain the focus on the objective







Sunday, 6 November 2016

Mobile Communication | CDMA (Code-Division Multiple Access) | Architecture | Advantages

Code-Division Multiple Access

CDMA (Code-Division Multiple Access) refers to any of several protocols used in second-generation (2G) and third-generation 3G wireless communications. CDMA employs analog-to-digital conversion (ADC) in combination with spread spectrum technology. Audio input is first digitized into binary elements. The frequency of the transmitted signal is then made to vary according to a defined pattern (code), so it can be intercepted only by a receiver whose frequency response is programmed with the same code, so it follows exactly along with the transmitter frequency. There are trillions of possible frequency-sequencing codes, which enhances privacy and makes cloning difficult.

CDMA Architecture elements

Mobile Station (MS):
The MS is the mobile subscriber equipment, which can originate and receive calls and communicate with the BTS.

Base Transceiver Station (BTS):
The BTS transmits and receives radio signals, realizing communication between the radio system and the mobile station
.
Base Station Controller (BSC):
The BSC implements the following functions:
  • Base Transceiver Station (BTS) control and management 
  • call connection and disconnection 
  • mobility management 
  • stable and reliable radio link provision for the upper-layer services by soft/hard handoff 
  • power control
  •  radio resource management.
Packet Control Function (PCF):
The PCF implements the R-P connection management. Because of the shortage of radio resources, some radio channels should be released when subscribers do not send or receive data, but the PPP connection is maintained continuously. The PCF can shield radio mobility for the upper-layer services via handoff.

Packet Data Service Node (PDSN):
The PDSN implements the switching of packet data services of mobile subscribers. One PDSN can be connected to multiple PCFs. It provides the interface between the radio network and the packet data network
.
Home Agent (HA):
The agent locates at the place where the Mobile Node opens its account; receive the registration information from MN, Similar as HLR in mobile network. Broadcast the accessible information of MN. Setup the tunnel between FA&HA. Transfer the data from other computer to the MN via the tunnel.

Mobile Switching Center (MSC): 
The MSC implements the service switching between the calling and called subscribers. One MSC is connected with multiple BSCs. The MSC can also be connected to the PSTN, ISDN or other MSCs. It provides the interface between the radio network and PSTN.

Visitor Location Register (VLR):
It is a dynamic database, stores the temporary information (all data necessary to set up call connections) of the roaming subscribers in the local MSC area.
VLR is used to store the subscriber information of all the MSs in its local area, which can be used to establish the incoming/outgoing call connections, to support basic services, supplementary services and mobility management.

Home Location Register (HLR):
It is a database for mobile subscriber management, the HLR (Home Location Register) is responsible for storing subscription information (telecom service subscription information and subscriber status), MS location information, MDN, IMSI (MIN), etc. The AC (Authentication Center) is physically combined with the HLR. It is a functional entity of the HLR, specially dedicated to the security management of the CDMA system. It stores the authentication information. It also prevents unauthorized subscribers from accessing the system and prevents the radio interface data from being stolen.

Advantages
  • Frequency  reuse
  • Large coverage
  • High spectrum capacity
  • High privacy
  • Soft handoff
  • Good voice quality
  • Perfect power control



Friday, 4 November 2016

OR(Operation Research) | Simulation | Types of Models | Advantages | Disadvantages

Simulation


Simulation is the imitation of the operation of a real-world process or system over time. The act of simulating something first requires that a model be developed; this model represents the key characteristics or behaviors/functions of the selected physical or abstract system or process.

Type of models 

Active models

Active models that attempt to reproduce living anatomy or physiology are recent developments. The famous "Harvey mannequin" was developed at the University of Miami and is able to recreate many of the physical findings of the cardiology examination, 

Interactive models

More recently, interactive models have been developed that respond to actions taken by a student or physician. Until recently, these simulations were two dimensional computer programs that acted more like a textbook than a patient. 

Computer simulators

Simulators have been proposed as an ideal tool for assessment of students for clinical skills. For patients, "cyber therapy" can be used for sessions simulating traumatic experiences, from fear of heights to social anxiety.
Programmed patients and simulated clinical situations, including mock disaster drills, have been used extensively for education and evaluation. These "lifelike" simulations are expensive, and lack reproducibility. A fully functional "3D" simulator would be the most specific tool available for teaching and measurement of clinical skills. 
Advantages

  1. Simulation is best suited to analyze complex and large practical problems when it is not possible to solve them through a mathematical method.
  2. Simulation is flexible, hence changes in the system variables can be made to select the best solution among the various alternatives.
  3. In simulation, the experiments are carried out with the model without disturbing the system.
  4. Policy decisions can be made much faster by knowing the options well in advance and by reducing the risk of experimenting in the real system


Disadvantages

  1. Simulation does not generate optimal solutions.
  2. It may take a long time to develop a good simulation model.
  3. In certain cases simulation models can be very expensive.
  4. The decision-maker must provide all information (depending on the model) about the constraints and conditions for examination, as simulation does not give the answers by itself.

Thursday, 3 November 2016

Computer Networking Objective type question with answer

Computer Networking 


1. Network of networks is known as _________
A. intranet. 
B. internet.
C. Local Area Network 
D. WAN.               
  ANSWER: B
2. An interconnection of ________________________ computers is called an Internet
 A. Distributed. 
B. Co-Ordinated. 
C. Autonomous. 
D. Integrated.              
ANSWER: C
 3. When a packet with the code is transmitted, it is received and processed by every machine on the network. This mode of operation is called
A. broadcasting. 
B. multi casting. 
C. unicasting. 
D. point-to-point.            
ANSWER: A
4. point-to-point transmission with one sender and one receiver is sometimes called ________
A. multicasting. 
B. unicasting. 
C. personal area network
 D. LAN.               
ANSWER: B
5. The entities comprising the corresponding layers on different machine are called ________
A. protocol. 
B. peers. 
C. interface. 
D. flow control.        
  ANSWER: B
6. When the packets are small and all the same size, they are often called ________
 A. packet switched. 
B. cells. 
C. circuit switched.
 D. virtual circuit.           
  ANSWER: B
 7. A collection of interconnected networks is called as __________
 A. internet. 
B. intranet. 
C. topology. 
D. interface.          
  ANSWER: A
 8. Starting around 1988, the more advanced ______ twisted pairs were introduced.
A. category3. 
B. category5. 
C. category 8. 
D. category10.              
  ANSWER: B
 9. Each ray is said to have a different mode, so a fiber having this property is called ________
A. unimode. 
B. singlemode
C. multimode. 
D. triplemode.         
  ANSWER: C
 10. The number of oscillations per second of a wave is called its ______
 A. wavelength. 
B. frequency.
C. spectrum.
 D. sequence.           
  ANSWER: B
 11. Most governments have set aside some frequency bands called the _______ bands for unlicensed usage .
A. IFS
B. ISM 
C. IRS 
D. IVS           
    ANSWER: B
12. The downward beams of a satellite can be broad , covering a substantial fraction of the earth's surface or narrow, covering an area only hundreds of kilometers in diameter. This mode of operation is known as a ____
A. bent pipe. 
B. foot print. 
C. uplink. 
D. downlink.           
ANSWER: A
13. The first geostationary satellite had a single spatial beam that illuminated about 1/3 of the earth's PM surface called its _______
 A. bent pipe.
 B. downlink
.C. foot print
.D. uplink.       
   ANSWER: C
14. Each end office has a number of outgoing lines to one or more nearby switching canters called ______
A. toll connecting trunks. 
B. toll office. 
C. local loop. 
D. end office.         
ANSWER: B
 15. __________ is the loss of energy as the signal propagates outward.
A. Attenuation. 
B. Distortion
C. Noise. 
D. Baud.             
  ANSWER: A
16. Sending packets to a group of stations is known as ______
A. broadcasting. 
B. multi-casting. 
C. uni-casting. 
D. point-to-point.            
ANSWER: D
17. Each area has a _________ agent which keeps track of all mobile hosts visiting the area.
A. mobile
 B. home. 
C. visitor. 
D. foreign.            
ANSWER: B
18. Ad-hoc networks are also called as ____________
A. MAN. 
B. MANET.
C. LAN. 
D. LANET.                    
ANSWER: B
19. An example for dynamic routing algorithm is _______.
A. Shortest path. 
B. Flooding.
C. Dijkstra. 
D. Distance vector.      
ANSWER: D
 20. ISO stands for _____________

A. International Standard Organization. 
B. International Student Organization.
C. Integrated Services Organization. 
D. Integrated standard organization.           
ANSWER: A

Tuesday, 1 November 2016

Software Engineering (Objective type question)

Software Engineering

1) What is Software ?
a.     Set of computer programs, procedures and possibly associated document concerned with the operation of data processing.
b.    A set of compiler instructions
c.     A mathematical formula  
d.    None of above
           Answer = A   
2) Which of the following is not the characteristic of software ?
a.     Software does not wear out
b.    Software is flexible
c.     Software is not manufactured
d.    Software is always correct
           Answer = D
3) Which of the following is not a product matrix ?
a.     Size
b.    Reliability
c.     Productivity
d.    Functionality
           Answer = C
4)Which of the following is not a process metric ?
a.     Productivity
b.    Functionality
c.     Quality
d.    Efficiency
           Answer = B
5) Efforts is measured in terms of ?
a.     Person - Months
b.    Persons
c.     Rupees
d.    Months
          Answer = A
6) Infrastructure software are covered under ?
a.     Generic Products
b.    Customised Products
c.     Generic and Customised Products
d.    None of the above
           Answer = A
7) Management of software development is dependent upon ?
a.     People
b.    Product
c.     Process
d.    All of above
          Answer = D
8) During software development which factor is most crucial ?
a.     People
b.    Process
c.     Product
d.    Project
          Answer = A
9) Milestones are used to ?
a.     Know the cost of the project
b.    Know the status of the project
c.     Know the user expectations
d.    None of the above
           Answer =A
10) The term module in the design phase refers to ?
a.     Functions
b.    Procedures
c.     Sub programs
d.    All of the above
          Answer =D .