Category Archives: Homework

homework PTI

Concept of programming language 10th edition chapter 6

Homework, KBP(programming language concept) Leave a comment

Assigned by mr. Tri Djoko Wahjono

4. Describe three string length options.
Static (fixed len), limited dynamic (fixed max len), dynamic (changeable len).

5. Define ordinal, enumeration, and subrange types.

Ordinal — easy put into 1-1 assoc with pos integers.
Enumeration — fixed (small) set of values.
subrange — a contiguous subsequence of ordinal type.

8. What are the design issues for arrays?
Legal subscripts, indexes range checked, when are ranges (and alloc) bound, Can arrays be init’d, ragged/rect multi-dim arrays allowed, max subscripts, slices supported?

9. Define static, fixed stack-dynamic, stack-dynamic, fixed heap-dynamic and heap-dynamic arrays. What are advantages of each?
static array — range & memory alloc before run-time. run-time efficient.
fixed stack-dynamic — range static, alloc done at decl time. Space efficient.
stack dynamic — range ^ storage alloc is dynamic. Flexible.
Fixed heap-dynamic — storage dynamic but fixed after alloc from heap.
Heap-dynamic — range & storage dynamic (change any time). Flexible.

17. Define row major order and column major order. row-major: elts of each row in adjacent mem loc. col-major: elts of each col in adjacent mem loc.

18. What is an access function for an array?
Formula calculating the addr of any element.

20. What is the structure of an associative array?
Unordered collection of elements indexed by an equal number of KEYS.

22. Define fully qualified and elliptical references to fields in records.
Fully qualified — use all level names of the record.
Elliptical — leaving out some record level names if ref is still unambiguous.

23. What’s the main difference between a record and a tuple?
Tuple’s elements are not named.

30. On what are Python’s list comprehensions based?
Math sets & functions.

31. Define union, free union, descriminated union.
Union– data type whose variables may store diff type values at diff times.
Free union — no type checking the current value of a union.
Discriminated unions — type checking using a discriminant.

32. What are design issues for unions?
Should type checking be required? Should unions be embedded in records?

33. Are unions in Ada always type checked?
Yes. Unconstrained unions run-time type checked.

35. What are design issues for pointers?
What are scope and lifetime of a pointer?
What is lifetime of a heap-dynamic variable?
Are pointers restricted as to the type of value to which they point?
Are pointers used for dynamic storage management, indirect addressing, or both?
Should the language support pointer types, reference types, or both?

36. What are two common problems with pointers?
1. Dangling pointer
2. Lost heap-dynamic variable.

41. Describe the lazy and eager approaches to reclaiming garbage.
Reference counter (eager)– maintain a ref count in every block. Update it whenever a pointer to block changes.
Mark-sweep (lazy) — when no more avail memory blocks, garbage collect by tracking every pointer into the heap and “marking” the block as used.

45. Define strongly typed.
Every type error is always detected (compile or run time).

49. Why are C and C++ not strongly typed.
C casts can override typing, C parameter type checking can be avoided, unions not type-checked.

Problems:

1. Boolean variables stored as single bits are very space efficient, but on most computers
access to them is slower than if they were stored as bytes.

4 Compare the tombstone and lock-and-key method of avoiding dangling pointers, from the points of view of safety and implementation cost.
tombstones take more memory (for the tombstones).
kock-&-key requires add’l cpu time on each ptr assignment to copy key as well as pointer. Pointer arithmetic could overwrite key in the heap.

7. What significant justification is there for the -> operator in C and C++?
The only justification for the -> operator in C and C++ is writability. It is slightly easier to write p -> q than (*p).q.

15. What are the arguments for and against Java’s implicit heap storage recovery, when compared with the explicit heap storage recovery required in C++? Consider real-time systems.
Implicit eliminates the creation of dangling pointers. Disadv: cpu-time to do recovery, sometimes when there’s plenty of heap storage so recovery isn’t necessary.

21. In what way is static type checking better than dynamic type checking?
a. Compiletime checking better run-time efficiency.
b. Uncovers errors earlier so less costly to remove.

Concept of programming language rev 10, chapter 1

Homework, KBP(programming language concept), Uncategorized Leave a comment

Assigned by Mr. Tri Djoko Wahjono
Review Questions
1. Why is it useful for a programmer to have some background in language design, even though he or she may never actually design a programming language?
Answer: Because, by knowing the language design programmer will find that there are many concepts that are common across programming languages. For example, control structures, error/exception handling, array/memory management.
Understanding these basics makes it easier for programmer to learn and adopt new languages.
2. How can knowledge of programming language characteristics benefit the whole computing community?
Answer:

3. What programming language has dominated scientific computing over the past 50 years?
Answer: Fotran (Formula Translator)

4. What programming language has dominated business applications over the past 50 years?
Answer: COBOL (Common Business-Oriented Language)

5. What programming language has dominated artificial intelligence overthe past 50 years?
Answer: Lisp

6. In what language is most of UNIX written?
Answer: C

7. What is the disadvantage of having too many features in a language?
Answer: If a language has a large number of different constructs, some programmers might not be familiar with all of them. This situation can lead to a misuse of some features and a disuse of others that may be either more elegant or more efficient, or both, than those that are used. It may even be possible, as noted by Hoare (1973), to use unknown features accidentally, with bizarre results.

8. How can user-defined operator overloading harm the readability of a program?
Answer: Because The compiler does not come to know how to make precision of this operator

9. What is one example of a lack of orthogonality in the design of C?
Answer: C has two kinds of structured data types, arrays and records (structs), records can be returned from functions but arrays cannot. A member of a structure can be any data type except void or a structure of the same type. An array element can be any data type except void or a function. Parameters are passed by value, unless they are arrays, in which case they are, in effect, passed by reference (because the appearance of an array name without a subscript in a C program is interpreted to be the address of the array’s first element).

Problem Sets
1. Do you believe that solving a problem in a particular algorithm step requires programming language skills? Support your answer!
Answer: Yes, because if our skill in one language (or concept) is bigger, then our capacity to have an abstract though is also getting bigger, for example the knowledge of array, if the so called “programmer” doesn’t know it, his mind may be stuck on even a simple code of program.

2. Who is said to be the first programmer in the history?
Answer: Ada Lovelace (http://en.wikipedia.org/wiki/Ada_Lovelace)

3. What are the disadvantages of multiple programming languages?
Answer: The disadvantages of multiple programming languages are:
a. Confusing, Every language has their own syntaxes. Therefore, programmers must remember syntaxes in every single language and also programmers have to know about the language behavior that may differ one to another.
b. It’s quite not convenient because if you have a task of making an application that include more than 1 domain of computer programming, it may be difficult.

4. In what way do the languages for scientific applications differ from the languages for business application? Support your view!
Answer: The main difference that differs them is the calculation itself, because on scientific application, the calculation may include a very small number (exponential float point) but on business one, the calculation will be much simpler than the scientific application.

5. In what way do the languages for Artificial Intelligence differ from the languages for web software? Support your view!
Answer: On artificial intelligence domain the usage of symbol is more dominant than the usage of computation, but in web software calculation is included to support the flexibility of the software.

6. Which characteristic of programming languages do you think are the most important and why?
Answer: Based on my opinion, the most important one will be its readability, because, nowadays, the focus of the programming is not on the efficiency, but on the cost of maintenance, thus the language itself must be easy to be read. If it is easy to be read, the maintenance progress will takes less time and the cost will be smaller too.

16. Does a Just-In-Time (JIT) implementation system affect the execution of the code? Why or why not?
Answer: JIT will not affect the execution of the code, because JIT does nothing to the code other than translating it to another language, the code itself isn’t changed.

17. Some programming languages-for example, SQL- use “=” to check the quality of two expressions, while C uses it to assign values to variable. Which of these, in your opinion, is more natural and least likely to result in syntax error? Support your answer!
Answer: Based on my opinion, C to me is more natural than SQL and less likely to make a syntax error, because we would more assign a value to a variable more than performing a selection by using an if-else statement. To use the selection itself, we must clearly assign the value or else it would print a bizarre output.

Discovering Computer 2011 Chapter 15 (LAST)

Homework, PTI 2016, Uncategorized 1 Comment

Assignment assigned by Mr.Tri Djoko Wahjono

True/False

1. True                                                        6. True
2. False                                                       7. True
3. True                                                        8. True
4. True                                                        9. False
5. False                                                     10. False

 

Multiple Choice

1. A                                                              5. D
2. C                                                              6. B
3. C                                                              7. D
4. A                                                              8. B

Matching

1. E                                                             6. B
2. D                                                            7. F
3. J                                                             8. I
4. G                                                            9. A
5. H                                                         10. C

Short Answer

1.the advantages of attending trade schools is that the program is much shorter time then collage and university program.
the factor that should be consider when selecting trade school is whether that trade school has articulation agreement with nearby collage or university to do the coursework transfer.

2. the benefits of professional growth and continuing education is to keep update with the new products and services in computer industry.
they way to keep update with the growth is with joining seminars, workshop, conference, conventions, and trade show.

3. certification should be chose by which skill do you master it. each IT have different area and skills.
four option for preparing for certificate :

  1. self-study, require high motivation and discipline
  2. Online training course, allow students to set their pace in interactive environment .
  3. instructor-led training, it has variety form starting from boot camps, academic style classes, and sponsored training.
  4. web resource, study from certification’s web site which include FAQs and links for training.

4. the main focus for programmer/developer certificate is certificate in networking and we design.
people who interested in programmer/developer certificate:

• Java programmers
• Mobile application developers
• Oracle database managers
• Programming consultants
• SQL programmers
• Web software developers
• XML developers

5. Hardware certification is focus on repair of a specific device to an integrated hardware solution that addresses a company’s current and future computing needs.
people who might interested in hardware certification :

• Cable installation technicians
• Computer repair technicians
• Corporate trainers
• Help desk specialists
• IT consultants
• System engineers and administrators

Discovering Computer 2011 chapter 14

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr.Tri Djoko Wahjono

Multiple Choice

1. C                                                      5. A
2. B                                                     6. D
3. A                                                    7. A
4. B                                                     8. D

Matching

1. H                                                     6. G
2. F                                                     7. A
3. B                                                     8. J
4. E                                                     9. I
5. D                                                  10. C

Short Answer

1. Responsibilities of mangers are that they coordinate and control an organization’s resources.
four activities that manager do to coordinate resource:

  • planning
  • organizing
  • leading
  • controlling

2. Content management system is an information system that is a combination of databases, software, and procedures that organizes and allows access to various forms of documents and other files, including images and multimedia content.
Content management system process content such as documents, files,images and multimedia.

3. 2 type of virtualization :

  • server virtualization, provides the capability to divide a physical server logically into many virtual servers.
  • storage virtualization, provides the capability to create a single logical storage device from many physical storage devices.

Cloud computing is an Internet service that provides computing needs to computer users and Grind computing combines many servers and/or personal computers on a network, such as the Internet, to act as one large computer. Reason companies using cloud and grind computing because provide flexible and massive online computing power.

4. 5 types of e-commerce :

  1. E-Retail
  2. Finance
  3. Travel
  4. Entertainment
  5. Media

E-retail, occurred when retailers use web to sell their product and service.
Finance, Online banking and online trading.
Travel, web provide many travel services.

5. the backup plans contain :

  1. location of backup data, supplies and equipment
  2. the personnel responsible for gathering backup resource and transporting them to the alternate computer facility
  3. a schedule indicates the order in which, and approximate time by which, each application should be up and running.

the factor that make backup plans successful that the organization must back up all critical resource.

Discovering Computer 2011 Chapter 13

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr. Tri Djoko Wahjono

A. True/False Mark T for True and F for False.
1.    Just as humans speak a variety of languages, programmers use a variety of programming languages and tools to create programs. (664)(True)
2.    With a procedural language, often called a third-generation language (3GL), a programmer uses a series of English-like words to write instructions. (666)(True)
3.    Programmers use Java Platform, Micro Edition (Java ME) to create programs for smart phones and other mobile devices. (670)(True)
4.    The Microsoft .NET Framework is a set of technologies that allows almost any type of program to run on the Internet or an internal business network, as well as stand-alone computers and mobile devices. (670)(True)
5.    HTML (Hypertext Markup Language) is a special formatting language that programmers use to format documents for display on the Web. (678)(True)
6.    ATOM allows Web developers to design pages specifically for microbrowsers. (679)(False)
7.    An applet usually runs slower than a script. (680)(False)
8.    Ruby on Rails is an open source framework that provides technologies for developing object-oriented, database-driven Web sites. (683)(True)
9.    Expression Web is used strictly on Linux Web servers. (685)(False)
10.    A selection control structure shows one or more actions following each other in order. (689)(False)

B. Multiple Choice Select the best answer.

1.    B. Interpreter
2.    C. Event driven
3.    C. Java
4.    A. SQL
5.    A. VBScript
6.    C. SharePoint Designer
7.    D. Dreamweaver
8.    B. encapsulation

C. Matching Match the terms with their definitions.

1.    G. object-oriented language that use just-in-time compiler
2.    D. object-oriented extension of the C programming language
3.    J. combines the benefits of an object-oriented language and a functional language
4.    I. nonprocedural language that enables users and programmers to access data in a database
5.    C. series of statements that instructs an application how to complete a task
6.    E. free, open source scripting language
7.    A. collection of tools that programmers use to interact with an environment such as a Web site or operating system
8.    H. process of testing a condition at the beginning of a loop
9.    B. process of testing a condition at the end of a loop
10.    f. process of programmers, quality control testers, and/or peers reviewing code in order to locate and fix errors so that the final programs work correctly
D. Short Answer Write a brief answer to each of the following questions.
1.    A compiler translates an entire program before executing it. An interpreter, by contrast, translates and executes one statement at a time. One advantage of an interpreter is that when it finds errors, it displays feedback immediately. The programmer can correct any errors before the interpreter translates the next line of code. The disadvantage is that interpreted programs do not run as fast as compiled programs.
2.    A major benefit of OOP is the ability to reuse and modify existing objects. For example, once a programmer creates an Employee object, it is available for use by any other existing or future program. Thus, programmers repeatedly reuse existing objects.
RAD (rapid application development) is a method of developing software, in which a programmer writes and implements a program and segments instead of waiting until the entire program is completed

3.    An IDE (integrated development environment) includes tools for building graphical user interfaces, an editor for entering program code, a compiler and/or interpreter, and a debugger (to remove errors)
Visual Studio suite contains:
a.    Visual Basic is a programming language that allows programmers easily to build complex task-oriented object-based programs.
b.    Visual C++ is a programming language based on C++

c.    Visual C# is a programming language that combines programming elements of C++ with an easier, rapid development environment

4.  XML (Extensible Markup Language) is an increasingly popular format for sharing data that allows Web developers to create customized tags, as well as use predefined tags, used for developing a single Web site whose content can be formatted to display appropriately on various devices. XML separates the Web page content from its format, allowing the Web browser to display the contents of a Web page in a form appropriate for the display device.

Two applications of XML are RSS 2.0, which stands for Really Simple Syndication, and ATOM, which are specifications that content aggregators use to distribute content to subscribers.

5. In documenting the solution, the programmer performs two activities:
(1) review the program code and,
(2) review all the documentation

First, programmers review the program for any dead code and remove it. Dead code is any program instructions that a program never executes. Next, programmers should run the program one final time to verify it still works. After reviewing the program code, the programmer gives the program and all of its documentation to the systems analyst. The documentation includes all charts, solution algorithms, test data, and program code listings that contain global and internal comments.

The programmer should be sure all documentation is complete and accurate. This becomes especially valuable if the program requires changes in the future. Proper documentation greatly reduces the amount of time a new programmer spends learning about existing prograams.

Discovering Computer 2011 chapter 12

Homework, PTI 2016, Uncategorized Leave a comment

A. True/False Mark T for True and F for False.

1.    An information system supports daily, short-term, and long-range activities of systems analysts. (620)(True)
2.    A systems analyst is responsible for designing and developing an information system. (622)(True)
3.    Operational feasibility measures whether an organization has the hardware, software, and people needed to support a proposed information system. (624)(False)
4.    Documentation should be updated only after a project is complete. (625)(False)
5.    In detailed analysis, the systems analysts develop the proposed solution with a specific hardware or software in mind. (631)(False)
6.    Structured English is a style of writing that describes the steps in a process. (633)(True)
7.    Object modeling combines the data with the processes that act on that data into a single unit, called a method. (634)(False)
8.    The only major activity of the design phase is the development of all of the details of the new or modified information system. (638)(False)
9.    Some VARs provide complete systems, known as a turnkey solution. (639)(True)
10.    During program design, the systems analyst prepares the program specification package, which identifies the required programs and the relationship among each program, as well as the input, output, and database specifications. (641)(True)
11.    With a pilot conversion, multiple locations in the organization use the new system. (644)(False)
B. Multiple Choice Select the best answer.

1.    A. Extreme project management
2.    B. PERT chart
3.    C. Project Request
4.    A. Mandated by management or some other governing body
5.    C. Decision table
6.    D. System proposal
7.    A. Computer-aided software engineering (CASE)
8.    D. Acceptance

C. Matching Match the terms with their definitions.
1.    H. responsible for designing and developing an information system
2.    E. controls the activities during system development
3.    A. becomes the first item in the project notebook and triggers the planning phase
4.    B. analysis and design technique that describes processes that transform inputs into outputs
5.    I. contains all the documentation and deliverables of a project
6.    G. stores a name, description, and other details about each data item
7.    F. an item that can contain both data and the procedures that read or manipulate that data
8.    J. mass-produced, copyrighted, prewritten software available for purchase
9.    C. working model of the proposed system
10.    K. determines whether the system is inefficient or unstable at any point

D. Short Answer Write a brief answer to each of the following questions.

1.    System development is a set of activities used to build an information system. Five phases in system development are:
a.    Planning
• Review project requests
• Prioritize project requests
• Allocate resources
• Form project development team
b.    Analysis
• Conduct preliminary investigation
• Perform detailed analysis activities:
-Study current system
-Determine user requirements
-Recommend solution
c.    Design
• Acquire hardware and software, if necessary
• Develop details of system
d.    Implementation
• Develop programs, if necessary
• Install and test new system
• Train users
• Convert to new system
e.    Operation, Support and Security
• Perform maintenance activities
• Monitor system performance
• Assess system security

2.    • Operational feasibility measures how well the proposed information system will work. Will the users like the new system? Will they use it? Will it meet their requirements? Will it cause any changes in their work environment? Is it secure?
• Schedule feasibility measures whether the established deadlines for the project are reasonable. If a deadline is not reasonable, the project leader might make a new schedule. If a deadline cannot be extended, then the scope of the project might be reduced to meet mandatory deadline.
• Technical feasibility measures whether the organization has or can obtain the hardware, software, and people needed to deliver and then support the proposed information system. For most information system projects, hardware, software, and people typically are available to support an information system. The challenge is obtaining funds to pay for these resources. Economic feasibility addresses funding.
• Economic feasibility, also called cost/benefit feasibility, measures whether the lifetime benefits of the proposed information system will be greater than its lifetime costs. A systems analyst often consults the advice of a business analyst, who uses many financial techniques, such as return on investment (ROI) and payback analysis, to perform the cost/benefit analysis

6 techniques used for gathering data are:
• Review Documentation
• Observe
• Survey
• Interview
• JAD session
• Research

3.    UML (Unified Modeling Language) has been adopted as a standard notation for object modeling and development. The UML is a graphical tool that enables analysts to document a system. It consists of many inter related diagrams. Each diagram conveys a view of the system. The latest UML version includes 13 different diagrams to assist the analyst in modeling the system. Two of the more common tools are the use case diagram and class diagram.
A use case diagram graphically shows how actors interact with the information system. An actor is a user or other entity such as a program. The function that the actor can perform is called the use case. Thus, a use case diagram shows actors and their use cases

A class diagram graphically shows classes and subclasses in a system .On a class diagram, objects are grouped into classes. Each class can have one or more lower levels called subclasses. Each subclass inherits the methods and attributes of the objects in its higher-level class. Every object in a class shares methods and attributes that are part of its higher-level class. This concept of lower levels inheriting methods and attributes of higher levels is called inheritance

4.    The operation, support, and security phase consists of three major activities:
(1) perform maintenance activities,
(2) monitor system performance, and
(3) assess system security

Information system maintenance activities include fixing errors in, as well as improving, a system’s operations.
performance monitoring is to determine whether the system is inefficient or unstable at any point.

5.    A computer security plan summarizes in writing all of the safeguards that are in place to protect an organization’s information assets. Computer Security Plan should do these 3 task, which are:

a. Identify all information assets of an organization, including hardware, software, documentation, procedures, people, data, facilities, and supplies.

b. Identify all security risks that may cause an information asset loss. Rank risks from most likely to least likely to occur. Place an estimated value on each risk, including lost business. For example, what is the estimated loss if customers cannot access computers for one hour, one day, or one week?

C .For each risk, identify the safeguards that exist to detect, prevent, and recover from a loss.

Discovering Computer 2011 chapter 11

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr.Tri Djoko Wahjono

A. True/False Mark T for True and F for False.

  1. Not all breaches to computer security are planned. (556)(True)
  2. The term, cyberwarfare, describes an attack whose goal ranges from disabling a government’s computer network to crippling a country. (557)(True)
  3. Many methods exist to guarantee completely a computer or network is safe from computer viruses and other malware. (560)(True)
  4. Cybercriminals install malicious bots on unprotected computers to create a zombie army.(562)(True)
  5. A honeypot is a computer that is isolated and, therefore, immune to attack. (564)(False)
  6. Biometric payment involves a customer’s fingerprint being read by a fingerprint reader that is linked to a payment method such as a checking account or credit card. (568)(True)
  7. Some businesses use a real time location system (RTLS) to track and identify the location of high-risk or high-value items. (570)(True)
  8. A program called a keygen, short for key generator, creates software registration numbers and sometimes activation codes. (571)(True)
  9. With public key encryption, both the originator and the recipient use the same secret key to encrypt and decrypt the data. (573)(False)
  10. A digital signature is a mathematical formula that generates a code from the contents of the message. (574)(False)
  11. Digital rights management (DRM) is a strategy designed to prevent illegal distribution of movies, music, and other digital content. (582)(True)
  12. Green computing involves reducing the electricity while using a computer, but the practice increases environmental waste. (583)(False)

B. Multiple Choice Select the best answer.

  1. B. Rootkit
  2. C. Back doors
  3. A. Denial of service attack
  4. C. Digital forensics
  5. C. Hardware theft
  6. D. Encryption key
  7. D. Power usage effectiveness (PUE)
  8. C. Social engineering

     C. Matching Match the terms with their definitions.

  1. J. potentially damaging computer program that affects, or infects, a computer negatively by altering the way the computer works without the user’s knowledge or permission
  2. D. organization or person you believe will not send a virus infected file knowingly
  3. E. area of the hard disk that holds an infected file until the infection can be removed
  4. G. group of compromised computers connected to a network such as the Internet that is being used as part of a network that attacks other networks, usually for nefarious purposes
  5. I. technique intruders use to make their network or Internet transmission appear legitimate to a victim computer or network
  6. C. protects a personal computer and its data from unauthorized intrusions
  7. B. private combination of words, often containing mixed capitalization and punctuation, associated with a user name that allows access to certain computer resources
  8. A. set of steps that can convert readable plaintext into unreadable ciphertext
  9. H. translates a personal characteristic into digital code
  10. F. uses special electrical components to smooth out minor noise, provide a stable current flow, and keep an overvoltage from reaching the computer and other electronic equipment

D. Short Answer Write a brief answer to each of the following questions.

 

  1. An antivirus program protects a computer against viruses by identifying and removing any computer viruses found in memory, on storage media, or on incoming files. Most antivirus programs also protect against other malware. A virus hoax is an e-mail message that warns users of a nonexistent virus or other malware. Often, these hoaxes are in the form of a chain letter that requests the user to send a copy of the e-mail message to as many people as possible
  2. Energy Star Is the guideline of green computing that is being developed by The United States Department of Energy (DOE) and the United States Environmental Protection Agency (EPA), this program is meant to reduce electricity usage of computer related devices Users should not store obsolete computers and devices in their basement, storage room, attic, warehouse, or any other location. Computers, monitors, and other equipment contain toxic materials and potentially dangerous elements including lead, mercury, and flame retardants. In a landfill, these materials release into the environment. Recycling and refurbishing old equipment are much safer alternatives for the environment.
  3. Information privacy refers to the right of individuals and companies to deny or restrict the collection and use of information about them. 5 ways of protecting information privacy are:

a. Fill in only necessary information on rebate, warranty and registration forms.

b. Do not preprint your telephone number or Social Security number on personal checks.

c.. Have an unlisted or unpublished telephone number.

d. If Caller ID is available in your area, find out how to block your number from displaying on the receiver’s system.

e. Do not write your telephone number on charge or

 4. A. If you receive an e-mail message that looks legitimate and requests you update credit card numbers, Social Security numbers, bank account numbers, passwords, or other private information, the FTC recommends you visit the Web site directly to determine if the request is valid. Never click a link in an e-mail message; instead, retype the Web address in your browser.

B. A phishing filter is a program that warns or blocks you from potentially fraudulent or suspicious Web sites.

Clickjacking is yet another similar scam. With clickjacking, an object that can be clicked on a Web site, such as a button, image, or link, contains a malicious program. When a user clicks the disguised object, a variety of nefarious events may occur. For example, the user may be redirected to a phony Web site that requests personal information or a virus may download to the computer.

 5. Content filtering is the process of restricting access to certain material on the Web. Content filtering opponents argue that banning any materials violates constitutional guarantees of free speech and personal rights. Many businesses use content filtering to limit employees’ Web access. One approach to content filtering is through a rating system of the Internet Content Rating Association (ICRA), which is similar to those used for movies and videos.

Chapter 10 DIscovering Computer 2011 Edition

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr. Tri Djoko Wahjono

A. True/False Mark T for True and F for False.

1. Data is a collection of unprocessed items, which can include text, numbers, images, audio, and video. (514)(True)

2. A database management system allows users to create forms and reports from the data in the database. (515)(True)

3. A range check ensures users enter only numeric data in a field. (523)(False)

4. A check digit often confirms the accuracy of a primary key value. (523)(True)

5. Databases require less memory, storage, and processing power than a file processing system. (526)(False)

6. A report is a window on the screen that provides areas for entering or modifying data in a database. (530)(False)

7. Continuous backup is a backup plan in which all data is backed up whenever a change is made. (532)(True)

8. A relationship is a link within the data in a database. (533)(True)

9. Normalization is a process designed to ensure the data within the relations (tables) is duplicated so that it is not lost. (534)(False)

10. The data in a distributed database exists in many separate locations throughout a network or the Internet. (536)(True)

B. Multiple Choice Select the best answer.

 

1. B. Timely

2. A. composite key

3. D. File maintenance

4. B. determines whether a number is within a specified range

 

5. A. less complexity

 

6. B. data dictionary

 

7. B. principle of least privilege

 

8. A. decides on the proper placement of field.

 

C. Matching Match the terms with their definitions.

1. E. uniquely identifies each field

2. G. defines the maximum number of characters a field can contain

3. C. specifies the kind of data a field can contain and how the field is used

4. B. field that uniquely identifies each record in a file

5. J. consists of simple, English-like statements that allow users to specify the data to display, print, or store

 

6. A. listing of activities that modify the contents of a database

 

7. I. uses the logs and/or backups to restore a database when it becomes damaged or destroyed

 

8. D. database that stores maps and other geographic data

 

9. H. person who focuses on the meaning and usage of data

 

10. f. creates and maintains the data dictionary, manages security of the database, monitors the performance of the database, and checks backup and recovery procedures

 

D. Short Answer Write a brief answer to each of the following questions.

1. Validation is the process of comparing data with a set of rules or values to find out if the data is correct.

There are 5 types of validation which are:

a. Alphabetic/Numeric Check

b. Range Check

c. Consistency check

d. Completeness check

e. Check digit.

 

2. Duplicating (redundancy) data in this manner wastes resources such as storage space and people’s time. When data is modified or added, file maintenance tasks consume additional time because people must update multiple files that contain the same data. Isolated Data, it is difficult to access data stored in separate files in different departments.

 

3 .Database approach means many programs and users share the data in the database, there are 5 reasons why we should use database approach:

strengths of the database approach.

• Reduced Data Redundancy — Most data items are stored in only one file, which greatly reduces duplicate data. For example, a school’s database would record a student’s name and address only once. When student data is entered or changed, one employee makes the change once.

• Improved Data Integrity — When users modify data in the database, they make changes to one file instead of multiple files. Thus, the database approach increases the data’s integrity by reducing the possibility of introducing inconsistencies.

•Shared Data — The data in a database environment belongs to and is shared, usually over a network, by the entire organization. This data is independent of, or separate from, the programs that access the data. Organizations that use databases typically have security settings to define who can access, add, modify, and delete the data in a database.

• Easier Access — The database approach allows nontechnical users to access and maintain data, providing they have the necessary privileges. Many computer users also can develop smaller databases themselves, without professional assistance.

• Reduced Development Time — It often is easier and faster to develop programs that use the database approach. Many DBMSs include several tools to assist in developing programs, which further reduces the development time.

 

4. How to use the simple query wizard is depending on the program itself, because every program usually has different simple query wizard. Query by Example Most DBMSs include query by example (QBE), a feature that has a graphical user interface to assist users with retrieving data.

 

5. Object-oriented databases have several advantages compared with relational databases: they can store more types of data, access this data faster, and allow programmers to reuse objects. An object oriented database stores unstructured data more efficiently than a relational database. Unstructured data can include photos, video clips, audio clips, and documents. When users query an object oriented database, the results often are displayed more quickly than the same query of a relational database. If an object already exists, programmers can reuse it instead of recreating a new object — saving on program development time.

4 example of object-oriented databases are:

• A multimedia database

• A groupware database

• A computer-aided design (CAD) database

• A hypertext database

Chapter 9 DIscovering Computer 2011 Edition

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr. Tri Djoko Wahjono

A.  True/False Mark T for True and F for False.

 

 

1. A communications channel is the media on which data, instructions, or information travel. (460)(False)

 

2. With video messaging, users can send short video clips, usually about 15 minutes, in addition to all picture messaging services. (464)(False)

 

3. A network is a collection of computers and devices connected together via communications devices and transmission media. (470)(True)

 

4. A local area network (LAN) is a network that covers a large geographic area using a communications channel that combines many types of media such as telephone lines, cables, and radio waves. (472)(False)

 

5. A Web server is a computer that delivers requested Web pages to your computer. (474)(True)

 

6. An intranet is an internal network that uses Internet technologies. (477)(True)

 

7. The 40-Gigabit Ethernet standard is the fastest of the Ethernet standards. (478)(False)

 

8. Bluetooth does not require line-of-sight transmission. (480)(True)

 

9. At distances of 10 meters (about 33 feet), the data transfer rate for UWB devices is 480 Mbps.(480)(False)

 

10. Fiber to the Premises (FTTP) uses fiber-optic cable to provide extremely high-speed Internet access to a user’s physical permanent location. (484)(True)

 

11. Latency is the time it takes a signal to travel from one location to another on a network. (491)(True)

B. Multiple Choice Select the best answer.

 

1. C. Visual voice mail

2. C. A Web conference

3. C. Provides for storage and management of a company’s documents

 

4. D. Mashup

 

5. B. Hubs and switches

6. A. RFID

 

7. D. Coaxial cable

 

8. B. Mobile TV

 

 

C. Matching Match the terms with their definitions.

1. E. allows users to send pictures and sound files, as well as short text messages, to a phone or other mobile device, or a computer

2. J. software that helps groups of people share information over a network

3. H. allows customers or suppliers to access part of a company’s intranet

4. D. specification to transmit data wirelessly among computers and devices via infrared light waves

 

5. F. service that carries voice, data, video, and multimedia at very high speeds

6. A. communications device that can convert digital signals to analog signals and analog signals to digital signals, so that data can travel along an analog telephone line.

 

7. G. communications device that sends and receives data and information to and from a digital line

 

8. B. amount of data, instructions, and information that can travel over a communications channel

 

9. C. materials or substances capable of carrying one or more signals

 

10. I. electrical disturbance that can degrade communications

 

D. Short Answer Write a brief answer to each of the following questions.

 

1. Text Messaging, also called SMS (short message service), capability allows users to send and receive short text messages, typically fewer than 300 characters, on a phone or other mobile device or computer.

Text messaging services typically provide users with several options for sending and receiving messages:

• Mobile to Mobile: send a message from your mobile device to another mobile device

• Mobile to E-Mail: send a message from you mobile device to an e-mail address anywhere in the world

• Web to Mobile: send a message from a text messaging Web site to a mobile device, or request that Web site alert a mobile device with messages of breaking news and other updates, such as sports scores, stock prices, and weather forecasts

• Mobile to Provider: send a message by entering a common short code (CSC), which is a four- or five-digit number assigned to a specific content or wireless service provider, followed by the message, such as a vote for a television program contestant or an entry for a sweepstakes.

 

2. A global positioning system (GPS) is a navigation system that consists of one or more earth-based receivers that accept and analyze signals sent by satellites in order to determine the receiver’s geographic location .So, GPS works by receiving signals sent by the satellites and analyze the sent signals. Nowadays, many vehicles use GPSs to provide drivers with directions or other information, such as alternate traffic routes, automatically call for help if the airbag is deployed, dispatch roadside assistance, unlock the driver’s side door if keys are locked in the car, and track the vehicle if it

is stolen. Newer GPS receivers also give drivers information about nearby points of interest, such as gas stations, restaurants, and hotels. Hikers and remote campers may carry GPS receivers in case they need emergency help or directions.

 

3. – LAN A local area network (LAN) is a network that connects computers and devices in a limited geographical area such as a home, school computer laboratory, office building or closely positioned group of buildings.

– MAN A metropolitan area network (MAN) is a high-speed network that connects local area networks in a metropolitan area such as a city or town and handles the bulk of communications activity across that region

-WAN A wide area network (WAN) is a network that covers a large geographic area (such as a city, country, or the world) using a communications channel that combines many types of media such as telephone lines, cables, and radio waves

These explanations lead us to an explanation to the reason of why they all are different. They are different because of the coverage area.

-A wireless LAN (WLAN) is a LAN that uses no physical wires. Computers and devices that access a wireless LAN must have built-in wireless capability or the appropriate wireless network card, USB network adapter, ExpressCard module, PC Card, or flash card. Very often, a WLAN communicates with a wired LAN for access to its resources, such as software, hardware, and the Internet.

 

4. A network topology refers to the layout of the computers and devices in a communications network. Three commonly used network topologies are star, bus, and ring. Most networks, including the Internet, use combinations of these topologies.

Five types of digital dedicated lines are ISDN lines, DSL, FTTP, T-carrier lines, and ATM

 

5. Three types of digital modems are ISDN modems, DSL modems, and cable modems. These modems typically include built-in Wi-Fi connectivity.

An ISDN modem sends digital data and information from a computer to an ISDN line and receives digital data and information from an ISDN line.

A DSL modem sends digital data and information from a computer to a DSL line and receives digital data and information from a DSL line. ISDN and DSL modems usually are external devices, in which one end connects to the telephone line and the other end connects to a port on the system unit.

A cable modem, sometimes called a broadband modem, is a digital modem that sendsand receives digital data over the cable television (CATV) network

Tugas GSLC 2

Homework, PTI 2016, Uncategorized Leave a comment

Assignment assigned by Mr. Tri Djoko Wahjono

Seagate Technology, an American company is one of the world’s largest manufacturers of hard disk drives Incorporated in 1978 as Shugart Technology, Seagate is currently incorporated in Dublin, Ireland and has its principal executive office in Cupertino, California.

Seagate has been a leader in the development of the hard disk drives since releasing the 5 MB ST-506 drive in 1980, the first 5.25-inch hard drive. They were a major supplier in the microcomputer market during the 1980s, especially after the introduction of the IBM XT in 1983. In 1989 they finalized the purchase of Control Data Corporation‘s Imprimis division, makers of the well regarded Wren product line. This gave Seagate access to the Wren’s voicecoil-based technology. In 1991 they introduced the 7,200 RPM Barracuda line, which remains their high-end offering to this day. They purchased Maxtor in 2006.

Seagate offers the industry’s broadest portfolio of hard disk drives, solid-state drives and solid-state hybrid drives. In addition, the company offers an extensive line of retail storage products for consumers and small businesses, along with data-recovery services for any brand of hard drive and digital media type.

Seagate employs more than 50,000 people around the world.

 

SanDisk Corporation is an American multinational corporation that designs, develops and manufactures data storage solutions in a range of form factors using the flash memory, controller and firmware technologies. It was founded in 1988 by Dr. Eli Harari and Sanjay Mehrotra, non-volatile memory technology experts. SanDisk became a publicly traded company on NASDAQ in November 1995. As of September 2011, its market capitalization is US$9.95 billion. SanDisk produces many different types of flash memory, including various memory cards and a series of USB removable drives. SanDisk markets to both the high-end and low-end sector demand for flash memory, and markets to other equipment makers as well as direct to consumers.

The company is headquartered in Milpitas, California, with offices or manufacturing facilities in 10 locations in Asia (including Taiwan, China and Japan), 6 locations in Europe (including the UK, Ireland and Spain), and 3 locations in Israel (Kfar Sava, Tefen and Omer)

SanDisk creates transformational memory products at world-class manufacturing facilities that produce more than two million products each day. We serve three high-growth mega markets–mobile, computing, and consumer electronics–each of which increasingly requires flash memory to deliver compelling benefits to consumers and businesses.

Samsung Storage devices are storage devices under trademark of Samsung. A South Korean multinational conglomerate company headquartered in Samsung Town, Seoul. It comprises numerous subsidiaries and affiliated businesses, most of them united under the Samsung brand, and is the largest South Korean chaebol.

Samsung storage devices are promoting Energy-saving High-performance Storage Solutions which Samsung’s storage devices span the spectrum of solutions for saving your data, images, audio, and video files. They have a broad line of energy saving Hard Disk Drives, fast and efficient Optical Disc Drives, and leading-edge Solid State Drives ready for consumers application. Their drives support OEMs and consumers in desktop/notebook PCs, consumer electronics, enterprise storage and more.

 

Hitachi, Ltd. (株式会社日立製作所 Kabushiki-gaisha Hitachi Seisakusho?) (Japanese pronunciation: [çitatɕi]) is a Japanese multinational engineering and electronics conglomerate company headquartered in Chiyoda, Tokyo, Japan. It is the parent of the Hitachi Group (Hitachi Gurūpu) and forms part of the DKB Group of companies. Hitachi is a diversified company and has 11 business segments: Information and Telecommunication Systems, Electrical Systems, Social and Industrial Systems, Automotive Systems, Electronic Component Devices, Construction, and Financial services.

Hitachi is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225 and TOPIX indices. Hitachi was ranked 38 on the 2012 Fortune Global 500 list and was ranked 129 on the 2012 Forbes Global 2000 list.

Hitachi was founded in 1910 by electrical engineer Namihei Odaira. The company’s first product was Japan’s first 5-horsepower electric induction motor, initially developed for use in copper mining. Odaira’s company soon became the domestic leader in electric motors and electric power industry infrastructure.

The company began as an in-house venture of Fusanosuke Kuhara‘s mining company in Hitachi, Ibaraki prefecture. Odaira moved headquarters to Tokyo in 1918. Long before that, he coined the company’s toponymic name by superimposing two kanji characters: hi meaning “sun” and tachi meaning “rise”. The young company’s national aspirations were conveyed by its original brand mark, which evoked Japan’s imperial rising sun flag.

Hitachi entered talks with Mitsubishi Heavy Industry in August 2011 about a potential merger of the two companies, in what would have been the largest merger between two Japanese companies in history.[3][4] The talks subsequently broke down and were suspended.[5]

In October 2012 Hitachi agreed to acquire the United Kingdom-based nuclear energy company Horizon Nuclear Power, which plans to construct up to six nuclear power plants in the UK, from E.ON and RWE for £700 million.

 

Computer software is a general term used to describe a collection of computer programs, procedures and documentation that perform some tasks on a computer system.[41] The term includes application software such as word processors which perform productive tasks for users, system software such as operating systems, which interface with computer hardware to provide the necessary services for application software, and middleware which controls and co-ordinates distributed systems.

Software applications for word processing, Internet browsing, Internet faxing, e-mail and other digital messaging, multimedia playback, computer game play and computer programming are common. The user of a modern personal computer may have significant knowledge of the operating environment and application programs, but is not necessarily interested in programming nor even able to write programs for the computer. Therefore, most software written primarily for personal computers tends to be designed with simplicity of use, or “user-friendliness” in mind. However, the software industry continuously provide a wide range of new products for use in personal computers, targeted at both the expert and the non-expert user.

PC(Personal Computer)

Microsoft Windows

Microsoft Windows is the collective brand name of several software operating systems by Microsoft. Microsoft first introduced an operating environment named Windows in November 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces (GUIs)[42][43] generated by Apple’s 1984 introduction of the Macintosh. The most recent client and server version of Windows are Windows 8 and Windows Server 2012, respectively, which was available at retail on October 26, 2012.

OS X

Main article: OS X

OS X (formerly Mac OS X) is a line of operating systems developed, marketed, and sold by Apple Inc.. OS X is the successor to the original Mac OS, which had been Apple’s primary operating system since 1984. OS X is a Unix-based graphical operating system. The most recent version of OS X is OS X Mountain Lion.

AmigaOS

AmigaOS is the default native operating system of the Amiga personal computer. It was developed first by Commodore International, and initially introduced in 1985 with the Amiga 1000. Early versions (1.0-3.9) run on the Motorola 68k series of 16-bit and 32-bit microprocessors, while the newer AmigaOS 4 runs only on PowerPC microprocessors. On top of a preemptive multitasking kernel called Exec, it includes an abstraction of the Amiga’s unique hardware, a disk operating system called AmigaDOS, a windowing system API called Intuition and a graphical user interface called Workbench. A command line interface called AmigaShell is also available and integrated into the system. The GUI and the CLI complement each other and share the same privileges. The current holder of the Amiga intellectual properties is Amiga Inc. They oversaw the development of AmigaOS 4 but did not develop it themselves, contracting it instead to Hyperion Entertainment. On 20 December 2006, Amiga Inc terminated Hyperion’s license to continue development of AmigaOS 4. However, in 30 September 2009, Hyperion was granted an exclusive, perpetual, worldwide right to AmigaOS 3.1 in order to use, develop, modify, commercialize, distribute and market AmigaOS 4.x and subsequent versions of AmigaOS (including AmigaOS 5).

Linux.

Linux is a family of Unix-like computer operating systems. Linux is one of the most prominent examples of free software and open source development: typically all underlying source code can be freely modified, used, and redistributed by anyone.[44] The name “Linux” comes from the Linux kernel, started in 1991 by Linus Torvalds. The system’s utilities and libraries usually come from the GNU operating system, announced in 1983 by Richard Stallman. The GNU contribution is the basis for the alternative name GNU/Linux.[45]

Known for its use in servers as part of the LAMP application stack, Linux is supported by corporations such as Dell, Hewlett-Packard, IBM, Novell, Oracle Corporation, Red Hat, Canonical Ltd. and Sun Microsystems. It is used as an operating system for a wide variety of computer hardware, including desktop computers, netbooks, supercomputers,[46] video game systems, such as the PlayStation 3, several arcade games, and embedded devices such as mobile phones, portable media players, routers, and stage lighting systems.

 

Server OS

Server-oriented operating systems tend to have certain features in common that make them more suitable for the server environment, such as

  • GUI not available or optional
  • ability to reconfigure and update both hardware and software to some extent without restart,
  • advanced backup facilities to permit regular and frequent online backups of critical data,
  • transparent data transfer between different volumes or devices,
  • flexible and advanced networking capabilities,
  • automation capabilities such as daemons in UNIX and services in Windows, and
  • tight system security, with advanced user, resource, data, and memory protection.

Server-oriented operating systems can, in many cases, interact with hardware sensors to detect conditions such as overheating, processor and disk failure, and consequently alert an operator or take remedial measures themselves.

 

FreeBSD – Based on the original BSD, a free alternative to UNIX, FreeBSD is free and open source and is known for its stability and its devil mascot.

OpenBSD – Another BSD variant, OpenBSD is known for its security-conscious configuration. The developers of the OS are also responsible for OpenSSH and OpenSSL.

Solaris – Once the brain child of the now defunct Sun Microsystems, Solaris is a commercial UNIX variant that uses many of the open tools available for BSD and Linux. In addition, there is a free version called OpenSolaris. All Solaris products are now owned by Oracle.

Windows Server is a brand name for a group of server operating systems released by Microsoft Corporation. All are part of Microsoft Servers. This brand includes the following software:

Microsoft has also produced Windows Small Business Server and Windows Essential Business Server (discontinued), software bundles which includes a Windows Server operating system and some other Microsoft Servers products.[3][4][5]

 

Mac OS X Server – Although most commonly perceived as a desktop OS, Mac OS X is a full-fledged Unix variant and contains many of the features of BSD. Like most commercial Unix offerings, OS X Server is designed to be run on Apple hardware, although there is a free and open source version, Darwin, that could technically run on anything.

Other Commercial UNIX variants – Many of the large server companies included their own proprietary UNIX operating systems already installed on their servers. Some of the big names were IBM’s AIX and HP’s HP-UX.

Embedded OS

An embedded operating system is an operating system for embedded computer systems. These operating systems are designed to be compact, efficient at resource usage, and reliable, forsaking many functions that non-embedded computer operating systems provide, and which may not be used by the specialized applications they run. They are frequently also referred to as real-time operating systems, and the term RTOS is often used (but it’s not correct to call them so) as a synonym for embedded operating system.

List of embedded OS:

Personal digital assistants (PDAs)

Digital media players

Smartphones and Mobile phones

Routers

Other embedded

Mobile OS

Operating system that designed to be used on mobile devices, such as mobile phones, PDAs, Handheld, most of them are usually embedded. List of them can be seen above