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Attribute	Description	Description
NETWORK	Technology	GSM/HSPA/LTE
LAUNCH	Announced	2015, June
BODY	Dimensions  Weight  Sim	152.2x78.7x7.5(5.99 x 3.10 x 0.30 in ) 171 g (6.03 oz) Optional Dual SIM ( Micro-SIM, dual stand-by)
DISPLAY	Type Size Resolution Multitouch	Super AMOLED Capacitive touchscreen, 16M colors 5.5 inches (~69.6% screen-to-body ratio) 720 x 1280 pixel (~267 ppi pixel density)  YES
PLATFORM	OS Chipset CPU GPU	Android OS, v5.1 (Lollipop) Qualcomm MSM8939 Snapdragon 615  Exynos 7580 Quad-core 1.4 GHz Cortex-A53 & quad-core 1.0 GHz Cortex-A53 Octa-core 1.5 GHz Adreno 405 Mali-T720MP2
MEMORY	Card slot Internal	microSD, up to 128 GB 16 GB, 1.5 GB RAM
CAMERA	Primary Features Video Secondary	13 MP, 4128 x 3096 pixels, autofocus, LED flash , Check quality Geo-tagging, touch focus, face detection, panorama 1080p@30fps, Check quality 5 MP, LED flash
SOUND	Alart Types Lound speaker 3.5mm Jack	Vibration; MP3, WAV ringtones YES YES
COMMUNICATION	WLAN Bluetooth Gps NFC Radio USB	Wi-Fi 802.11 b/g/n, Wi-Fi Direct, hotspot v4.1, A2DP Yes, with A-GPS, GLONASS Yes (Snapdragon model only) FM radio with RDS; recording microUSB v2.0
FEATURES	Sensors Messaging Browser Java	Accelerometer, proximity SMS(threaded view), MMS, Email, Push Mail, IM HTML5 No - ANT+ support - Active noise cancellation with dedicated mic - MP4/WMV/H.264 player - MP3/WAV/WMA/eAAC+/FLAC player - Photo/video editor - Document viewer
BATTERY	Stand-by Talk Music Play	Li-Ion 3000 mAh battery Up to 18 h (3G) Up to 76 h
MICS	Colors Price	White, Black, Gold 6 to 10
TESTS	Performance Display Camera LoudSpeaker AudioQuality Bettery life

Computer Fundamental arithmetic logic unit Memory segment

Computer Fundamental arithmetic logic unit Memory segment 

shortcomings of ENIAC. It presented an impressive feat electronic engineering  and used for many year to solve ballistic problems.

1.    Describe about output unit and ARITHMETIC LOGIC UNIT

 

Answer: The job of an output unit is just the reverse of that of an input unit. It supplies information and results of computation to the outside world. Thus it links the computer with the external environment As computers work with binary code, the results produced are also in the binary form. Hence, before supplying the results to the outside world, it must be converted to human acceptable (readable) form. This task is accomplished by units called output interfaces. Output interfaces arc designed to match the unique physical or electrical characteristics of output devices (terminals, printers, etc.) to the requirements of the external environment.

In short, the following functions are performed by an output unit:

1.   h accepts the result produced by the computer which are in coded rum and hence cannot be  easily understood by u

2.   It  converts these  coded  results   to  human acceptable (readable)              from

3.   II supplies the convict cod insults lo the outside work

             ARITHMETIC LOGIC UNIT

The arithmetic logic unit (ALU) of a computer system is the place where the actual execution of the instructions takes place during the processing operation. To the more precise. Ill calculations. re performed and all comparisons (decisions) are made in the ALU. The data and instructions, stored in the primary storage prior to processing, are transferred as and when needed to the ALU where processing takes place. No processing is done in the primary storage unit Intermediate faults generated in the -ALU arc temporarily transferred badly. to the primary storage until needed at a later time. Data may thus move from primary storage to ALU and back again lo storage many times before the processing is over.  After the completion of processing, the final re suit, which are stored in the storage unit arc released to an output device.

The and number of arithmetic and loge operations (hat a computer can perform is determined by the engineering design of the ALU.  However almost all

Memory Segment

Memory Segment : A memory segment is a block of 2¹⁶ consecutive memory location /bytes, starting with 0. A segment number is 16 bits, so the highest segment number is FFFFh.

   Within a segment, a memory location is specified by giving an offset. This is the number of bytes from the beginning  of the segment offset can be given as a 16 bit number.

The first byte in a segment has offset 0 and the last offset in a segment is FFFFh.

Thus a memory location can be specified by providing a segment number and an offset. For example A4FB : 4872h . Means 4872h offset within the segment A4FBh.

Thus from of addressing is know as logical address.

Physical address :

Segment 0 starts with offset 0. so the physical address of segment 0’s starting.

Segment 0 onto with offset FFFFh so the physical address of segment 0’s ending is.

              Segment               Offset

               0000h                  0000h

         0000 X 10h + 0000h = 00000 + 0000 = 00000h

From the calculation, we have seen that every segment starts after 10h = 16 bytes. And one segment overlaps with another. For this reason we call every 10h a paragraph and we call an address that is divisible by 16 a paragraph boundary.

* Logical address = Segment : Offset

* Physical address = Segment X 10h + Offset

Computer Fundamental Character satiric of computer

Computer Fundamental Character satiric of computer

1. Character satiric of computer?

Answer: speed. A computer is a very fast device. It can perform in a few second the amount of worked that a human being does an entire year. if he worked day and night and did nothing else. To put it on a different manner, a computer dose on one minute what world take a man his entire lifetime. While talking about the speed of a computer , we do not talk in terms of seconds or even milliseconds (10^-3), the nanoseconds (10^-9 ), and even the picoseconds (10^-12), the . A powerful computer is capable of performing about 3 to 4 million simple arithmetic operations per second.

                  Accuracy. 
                 The accuracy of a computer consistently high and the degree if accuracy of a                 particular computer depends upon its design but for a particular computer each             and every calculation is performed with the same accuracy. Errors can occur in             a computer but these are mainly due to human rather than technological                         weaknesses that is due to imprecise thinking by the programmer (a person who             writes instructions for a computer to solve a particular problem ) or due to                        inaccurate data.

1.       Diligence.

       Unlike human beiges, a computer is free from monotony tiredness, lack of concentration, etc. and hence can work for hours together without creation any error and without grumbling due to this property computers obviously score over human beings in doing routine type of jobs which require great accuracy. If ten million calculations have to be performed, a computer will perform the ten million calculations with exactly the same accuracy and speed as the first one.

2.       Versatility.

Versatility is one of the most wonderful thing about the computer one moment it is preparing the results of particular examination the next moment is busy

Preparing electricity bill and in between it may be helping an office secretary to trace an important letter in seconds. All that is required to change its talent is to slip n a new program (a sequence of instructions for the computer) into it briefly; a computer is capable of performing almost any task provided that the task can be reduced to a series of logic steps.

Power of remembering:

 As a human being acquires ne w knowledge, the brain subconsciously selects what it feels

                To be important and worth retaining in its memory and relegates un important details to the                back f the mind or just forgets them. With computers, this is not the case. A computer can                    store and recall any amount of information because of its secondary storage (a type of                        detachable memory) capability. Every piece of information can be retained as long as desired              by the user and can be recalled as and when required. Even after several years. The  it was                  fed to the computer. A computer forgets or loses. Certain information only when it is asked to            do so . So it is entirely up to the user to make a computer retain or forger particular                              information. 

2. briefly describe second Generation of computer?

Answer:  second generation (1955-1964)

The transistor, a smaller and more reliable successor to the vacuum tube, was invented in 1947. However, computers that used transistors were not produced in quantity until over a decade later. The second generation emerged with transistors being the brain of the computer with both the first and the second generation computer the basic component was discrete or separate entity. The many thousands of individual components had to be assembled by hand not functioning circuits. The manual assembly of individual components and the cost of labor involved at this assembly stage made the commercial production of these computers difficult and costly

Advantage

• 1.       smaller in size as compared to first generation computers
• 2.       more reliable
• 3.       less heat generated
• 4.       These computers were able to reduce computational times from milliseconds to microseconds.
• 5.       Less prone to hardware failures
• 6.       Better portability
• 7.       Wider commercial use

Disadvantage

1.       Air conditioning required

2.       Frequent maintenance required

3.       Manual assembly of individual components into a functioning unit was required

4.       Commercial production was difficult and costly

3. Describe about the ENIAC ?

 Answer:  The electronic numerical integrator An calculator (ENIAC) was the first all electronic computer. It was constructed at the more school of engineering of the University of Pennsylvania U.S.A By design team led by professors J. prosper Eckert and John mannishly.

Computer Fundamental

Computer Fundamental

How you Managing Complexity?

Ans: for managing complexity we maintain four term that are Modularity, Abstraction,   Hierarchy and Layers.

Modularity:

! Also known as "Divide and Conquer"

! This approach that words best for the Bank Vault Problem

! Idea - Group the system components into a smaller set of interacting subsystems

! Which dimension of complexity does this reduce?

! Example - compilation of a large program

Abstraction

! Hide implementation details behind well specified interfaces

! Choose abstractions to minimize inter-module interactions

! Align modules (or groups of modules) and abstractions

! Careful with performance tradeoffs

Hierarchy

! Organize modules into a tree-like structure

! each node represents a set of modules

! Modules can interact only along the links

! Examples: Businesses

! Reduces interactions from O(n2) to O(n)

Layers

! Organizing technique that uses modularity and abstraction

! Create a different way of looking at an existing system, without adding more functionality

! Example 1: logic gates + memory cells: microprocessor:  machine language processor: Java processor

Briefly describe about Iteration and KIS of computer system?

Ans: all are describe bellow:

Iteration

! Start with a simple, working system that meets a few key requirements (sound familiar?)

! Use what you learn to evolve the system

! Learn from your mistakes early on (study failures!)

! Import new technology as it arrives

! Tradeoffs?

! “The kitchen sink”

! Harder to change early decisions as time goes on

KIS

! Keep It Simple

! “If in doubt, leave it out” - anonymous

! “Everything should be made as simple as possible, but no simpler” - Albert Einstein

! Problem - Convincing someone that leaving something out will help in the long term

! “we need more features to beat competitors!”

! “we’ve already tested each of the 100 features on its own - all we have to do is integrate

them”

What is a Distributed System? Note down the Design Issues of Distribution system ?

Ans:

! Tanenbaum and van Renesse: A distributed system is one that looks to its users like an ordinary, centralized, system but runs on multiple independent CPUs

! Symptoms? Shroeder:

! Multiple, independent processing units

! Processors communicate via a hardware interconnect

! Processing unit failures are independent

! Manage resource sharing

! State is shared among processors

Design Issues of Distribution system are

! Scaling

! Communication

! Coordination

! Transparency

! Naming

! Load sharing

! Consistency

! Failures

! Security

! Heterogeneity

! Mobility

Describe about Communication, Consistency and Load Sharing?

Ans: This short description given bellow:

Communication

! Messages can have many characteristics:

! Length, priority, streams

! Communication medium properties affect communication performance

! bandwidth, latency, multi-cast capability, message prioritization

Consistency

! Since we assume network links can fail at any time, replication is required to maintain consistency for longer computations

! Replication of data

! Replication of computation

! Costs associated with consistency:

! Reduction in the amount of effective resources

! Managing extended failures

Load Sharing

! Local vs. non-local

! e.g., communication failure less likely in local clusters of processors

! Process migration can be expensive

! What about a system that knows the load of each machine, then assigns computation?

! Doesn't scale well

! Issues - Turning Completeness, Propagation Delay

Shortly describe about NFS Mounting and NFS Performance Improvement?

Ans:-

NFS Mounting are bellow:-

_ Local file systems that can be mounted remotely stored in /etc/exports

_ Hard mounts - file system access is a blocking operation

_ Soft mounts - file system access is a non-blocking operation

_ less Transparency

_ Allows client to determine what happens when a failure occurs

_ Not backwards compatible!

8

NFS Performance Improvements are describe bellow:-

_ Locally, typically use read-ahead, write-behind

_ NFS Servers can use read-ahead as-is, but write caching raises fault tolerance issues

_ e.g., what if the server stores a write in the cache, and then dies?

_ Option 1: write-through caching

_ Problem: Performance bottleneck!

_ Option 2: Writes are cached; client determines when cache is written