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Sebelum memutuskan untuk membeli software berlisensi, ada baiknya mengetahui lebih dulu jenis lisensi apa yang sesuai dengan kebutuhan. Ada tiga jenis lisensi yang selama ini dikenal, yaitu: OEM, OLP, dan FPP. 1. Lisensi Jenis OEM (Original Equipment Manufacturer)
Harga lisensi jenis ini adalah yang termurah. 2. Lisensi Jenis OLP (Open License Program)
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Minggu, 05 April 2009
jenis-jenis lisensi software
Minggu, 22 Maret 2009
Extreme Programming
From Wikipedia, the free encyclopedia
Planning and feedback loops in Extreme Programming (XP) with the time frames of the multiple loops.
| Software development process | |
| Activities and steps | |
|---|---|
| Requirements · Specification Architecture · Design Implementation · Testing Deployment · Maintenance | |
| Models | |
| Agile · Cleanroom · DSDM Iterative · RAD · RUP · Spiral Waterfall · XP · Scrum · V-Model FDD | |
| Supporting disciplines | |
| Configuration management Documentation Quality assurance (SQA) Project management User experience design | |
| Tools | |
| Compiler · Debugger · Profiler GUI designer Integrated development environment | |
Extreme Programming (XP) is a software engineering methodology (and a form of agile software development)prescribing a set of daily stakeholder practices that embody and encourage particular XP values (below). Proponents believe that exercising these practices—traditional software engineering practices taken to so-called "extreme" levels—leads to a development process that is more responsive to customer needs ("agile") than traditional methods, while creating software of better quality.
Proponents of Extreme Programming and agile methodologies in general regard ongoing changes to requirements as a natural, inescapable and desirable aspect of software development projects; they believe that adaptability to changing requirements at any point during the project life is a more realistic and better approach than attempting to define all requirements at the beginning of a project and then expending effort to control changes to the requirements.
However, XP has been noted for several potential drawbacks, as compared to more document-based methodologies, including problems with unstable requirements, no documented compromises of user conflicts, and lack of an overall design spec or document (see below: Controversial aspects).
Contents[hide] |
Extreme Programming was created by Kent Beck during his work on the Chrysler Comprehensive Compensation System (C3) payroll project.Beck became the C3 project leader in March 1996 and began to refine the development method used in the project and wrote a book on the method (in October 1999, Extreme Programming Explained was published). Chrysler cancelled the C3 project in February 2000[citation needed].
Although Extreme Programming itself is relatively new, many of its practices have been around for some time; the methodology, after all, takes "best practices" to extreme levels. For example, the "practice of test-first development, planning and writing tests before each micro-increment" was used as early as NASA's Project Mercury, in the early 1960s (Larman 2003). Refactoring, modularity, bottom-up and incremental design were described by Leo Brodie in his book published in 1984.
Origins
Most software development in the 1990s was shaped by two major influences: internally, object-oriented programming replaced procedural programming as the programming paradigm favored by some in the industry; externally, the rise of the Internet and the dot-com boom emphasized speed-to-market and company-growth as competitive business factors. Rapidly-changing requirements demanded shorter product life-cycles, and were often incompatible with traditional methods of software development.
The Chrysler Comprehensive Compensation System was started in order to determine the best way to use object technologies, using the payroll systems at Chrysler as the object of research, with Smalltalk as the language and GemStone as the data access layer. They brought in Kent Beck, a prominent Smalltalk practitioner, to do performance tuning on the system, but his role expanded as he noted several issues they were having with their development process. He took this opportunity to propose and implement some changes in their practices based on his work with his frequent collaborator, Ward Cunningham.
- The first time I was asked to lead a team, I asked them to do a little bit of the things I thought were sensible, like testing and reviews. The second time there was a lot more on the line. I thought, "Damn the torpedoes, at least this will make a good article," [and] asked the team to crank up all the knobs to 10 on the things I thought were essential and leave out everything else. —Kent Beck
Beck invited Ron Jeffries to the project to help develop and refine these methods. Jeffries thereafter acted as a coach to instill the practices as habits in the C3 team.
Information about the principles and practices behind XP was disseminated to the wider world through discussions on the original Wiki, Cunningham's WikiWikiWeb. Various contributors discussed and expanded upon the ideas, and some spin-off methodologies resulted (see agile software development)Current state
XP created quite a buzz in the late 1990s and early 2000s, seeing adoption in a number of environments radically different from its origins.
The high discipline required by the original practices often went by the wayside, causing some of these practices that were thought too rigid to be deprecated or left undone on individual sites. Agile development practices have not stood still, and XP is still evolving, assimilating more lessons from experiences in the field. In the second edition
Extreme Programming topics
Goals of XP
"Extreme Programming Explained" describes Extreme Programming as being:
- An attempt to reconcile humanity and productivity
- A mechanism for social change
- A path to improvement
- A style of development
- A software development discipline
The main aim of XP is to reduce the cost of change. In traditional system development methods (such as SSADM) the requirements for the system are determined at the beginning of the development project and often fixed from that point on. This means that the cost of changing the requirements at a later stage (a common feature of software engineering projects) will be high.
XP sets out to reduce the cost of change by introducing basic values, principles and practices. By applying XP, a system development project should be more flexible with respect to changes.
XP activities
XP describes four basic activities that are performed within the software development process.
- Coding
- Listening
- Programmers do not necessarily know anything about the business side of the system under development. The function of the system is determined by the business side. For the programmers to find what the functionality of the system should be, they have to listen to business. Programmers have to listen "in the large": they have to listen to what the customer needs. Also, they have to try to understand the business problem, and to give the customer feedback about his or her problem, to improve the customer's own understanding of his or her problem. Communication between the customer and programmer is further addressed in The Planning Game.
- Feedback
- Within Extreme Programming, feedback relates to different dimensions of the system development:
- Feedback from the system: by writing unit tests,[5] or running periodic integration tests, the programmers have direct feedback from the state of the system after implementing changes.
- Feedback from the customer: The functional tests (aka acceptance tests) are written by the customer and the testers. They will get concrete feedback about the current state of their system. This review is planned once in every two or three weeks so the customer can easily steer the development.
- Feedback from the team: When customers come up with new requirements in the planning game the team directly gives an estimation of the time that it will take to implement.
- Feedback is closely related to communication and simplicity. Flaws in the system are easily communicated by writing a unit test that proves a certain piece of code will break. The direct feedback from the system tells programmers to recode this part. A customer is able to test the system periodically according to the functional requirements, known as user stories.To quote Kent Beck, "Optimism is an occupational hazard of programming, feedback is the treatment."[citation needed]
Rules of play
Rules of play that make XP unique are defined below; these rules are based on XP’s values: Communication, Simplicity, Feedback, Courage.
- Continuous testing: Work produced must be continuously validated through testing.
- Clearness and quality of code: All code written for potential use in the software product must clearly express every concept and have clarity, contain no duplication and no superfluous parts and pass all the unit tests.
- Common vocabulary: There is a sketch of the product guide all development with a simple shared story of how the whole system works. So everyone involved could grasp the essence of the project in a term universally understood.
- Everybody has the authority: Everybody has the authority and at least two people have the understanding necessary to do any task
Principles
The principles that form the basis of XP are based on the values just described and are intended to foster decisions in a system development project. The principles are intended to be more concrete than the values and more easily translated to guidance in a practical situation.
http://www.sei.cmu.edu/cmmi/presentations/sepg05.presentations/jarvis-gristock.pd
Agile software development
From Wikipedia, the free encyclopedia
| Software development process | |
| Activities and steps | |
|---|---|
| Requirements · Specification Architecture · Design Implementation · Testing Deployment · Maintenance | |
| Models | |
| Agile · Cleanroom · DSDM Iterative · RAD · RUP · Spiral Waterfall · XP · Scrum · V-Model FDD | |
| Supporting disciplines | |
| Configuration management Documentation Quality assurance (SQA) Project management User experience design | |
| Tools | |
| Compiler · Debugger · Profiler GUI designer Integrated development environment | |
Agile software development is a group of software development methodologies that are based on similar principles. Agile methodologies generally promote a project management process that encourages frequent inspection and adaptation, a leadership philosophy that encourages teamwork, self-organization and accountability, a set of engineering best practices that allow for rapid delivery of high-quality software, and a business approach that aligns development with customer needs and company goals. Conceptual foundations of this framework are to be found in modern approaches to operations management and analysis such as lean manufacturing, soft systems methodology, speech act theory (network of conversations approach), and Six Sigma.
Introduction
There are many specific agile development methods. Most promote development iterations, teamwork, collaboration, and process adaptability throughout the life-cycle of the project.
Agile methods choose to do things in small increments with minimal planning, rather than long-term planning. Iterations are short time frames (known as 'timeboxes') which typically last from one to four weeks. Each iteration is worked on by a team through a full software development cycle, including planning, requirements analysis, design, coding, unit testing, and acceptance testing when a working product is demonstrated to stakeholders. This helps to minimize the overall risk, and allows the project to adapt to changes quickly. Documentation is produced as required by stakeholders. An iteration may not add enough functionality to warrant releasing the product to market, but the goal is to have an available release (with minimal bugs) at the end of each iteration. Multiple iterations may be required to release a product or new features.
Team composition in an agile project is usually cross-functional and self-organizing without consideration for any existing corporate hierarchy or the corporate roles of team members. Team members normally take responsibility for tasks that deliver the functionality of an iteration. They decide for themselves how they will execute during an iteration.
Agile methods emphasize face-to-face communication over written documents, when working in the same location, or in different locations but having video contact daily, communicating by videoconferencing, voice, e-mail etc.
Most agile teams are located in a single open office to facilitate such communication. Team size is typically small (5-9 people) to help make team communication and team collaboration easier. Larger development efforts may be delivered by multiple teams working toward a common goal or different parts of an effort. This may also require a coordination of priorities across teams.
No matter what development disciplines are required, each agile team will contain a customer representative. This person is appointed by stakeholders to act on their behalf and makes a personal commitment to being available for developers to answer mid-iteration problem-domain questions. At the end of each iteration, stakeholders and the customer representative review progress and re-evaluate priorities with a view to optimizing the return on investment and ensuring alignment with customer needs and company goals.
Most agile methodologies include a routine and formal daily face-to-face communication among team members. This specifically includes the customer representative and any interested stakeholders as observers. In a brief session, team members report to each other what they did yesterday, what they intend to do today, and what their roadblocks are. This standing face-to-face communication prevents problems being hidden.
Agile methods emphasize working software as the primary measure of progress. Combined with the preference for face-to-face communication, agile methods usually produce less written documentation than other methods. In an agile project, documentation and other project artifacts all rank equally with working product. Stakeholders are encouraged to prioritize them with other iteration outcomes based exclusively on business value perceived at the beginning of the iteration.
Specific tools and techniques such as continuous integration, automated or xUnit test, pair programming, test driven development, design patterns, domain-driven design, code refactoring and other techniques are often used to improve quality and enhance project agility.
History
The modern definition of agile software development evolved in the mid-1990s as part of a reaction against "heavyweight" methods, perceived to be typified by a heavily regulated, regimented, micro-managed use of the waterfall model of development. The processes originating from this use of the waterfall model were seen as bureaucratic, slow, demeaning, and inconsistent with the ways that software developers actually perform effective work. A case can be made that agile and iterative development methods are a return to development practice seen early in the history of software development.Initially, agile methods were called "lightweight methods." In 2001, prominent members of the community met at Snowbird, Utah, and adopted the name "agile methods." Later, some of these people formed The Agile Alliance, a non-profit organization that promotes agile development.
An adaptive software development process was introduced in a paper by Edmonds (1974).Notable early Agile methods include Scrum (1995), Crystal Clear, Extreme Programming (1996), Adaptive Software Development, Feature Driven Development, and Dynamic Systems Development Method (DSDM) (1995). These are typically referred to as Agile Methodologies since the Agile Manifesto was published in 2001.
Principles behind agile methods
See also: Agile Manifesto
Agile methods are a family of development processes, not a single approach to software development. In 2001, 17 prominent figures in the field of agile development (then called "light-weight methods") came together at the Snowbird ski resort in Utah to discuss ways of creating software in a lighter, faster, more people-centric way. They created the Agile Manifesto, widely regarded as the canonical definition of agile development and accompanying agile principles. The Agile Manifesto states:
We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value:
That is, while there is value in the items on the right, we value the items on the left more.
- Individuals and interactions over processes and tools
- Working software over comprehensive documentation
- Customer collaboration over contract negotiation
- Responding to change over following a plan
Some of the principles behind the Agile Manifesto are:
- Customer satisfaction by rapid, continuous delivery of useful software
- Working software is delivered frequently (weeks rather than months)
- Working software is the principal measure of progress
- Even late changes in requirements are welcomed
- Close, daily cooperation between business people and developers
- Face-to-face conversation is the best form of communication (Co-location)
- Projects are built around motivated individuals, who should be trusted
- Continuous attention to technical excellence and good design
- Simplicity
- Self-organizing teams
- Regular adaptation to changing circumstances
The manifesto spawned a movement in the software industry known as agile software development.
In 2005, Alistair Cockburn and Jim Highsmith gathered another group of people—management experts, this time—and wrote an addendum, known as the PM Declaration of Interdependence.
The functioning principles of Agile can be found in lean manufacturing and six sigma. These concepts include error proofing, eliminating waste, creating flow, adding customer value, and empowering workers. The concepts were first formally espoused in the 14 principles of the Toyota Way, the two pillars of the Toyota Production System (Just-in-time and smart automation), the 5S methodology, and Deming’s 14 points. These have been summarized in the seven points of lean software development.
Comparison with other methods
Agile methods are sometimes characterized as being at the opposite end of the spectrum from "plan-driven" or "disciplined" methods. This distinction is misleading, as it implies that agile methods are "unplanned" or "undisciplined". A more accurate distinction is that methods exist on a continuum from "adaptive" to "predictive".Agile methods lie on the "adaptive" side of this continuum.
Adaptive methods focus on adapting quickly to changing realities. When the needs of a project change, an adaptive team changes as well. An adaptive team will have difficulty describing exactly what will happen in the future. The further away a date is, the more vague an adaptive method will be about what will happen on that date. An adaptive team can report exactly what tasks are being done next week, but only which features are planned for next month. When asked about a release six months from now, an adaptive team may only be able to report the mission statement for the release, or a statement of expected value vs. cost.
Predictive methods, in contrast, focus on planning the future in detail. A predictive team can report exactly what features and tasks are planned for the entire length of the development process. Predictive teams have difficulty changing direction. The plan is typically optimized for the original destination and changing direction can cause completed work to be thrown away and done over differently. Predictive teams will often institute a change control board to ensure that only the most valuable changes are considered.
Agile methods have much in common with the "Rapid Application Development" techniques from the 1980/90s as espoused by James Martin and others.
Contrasted with other iterative development methods
Most agile methods share other iterative and incremental development methods' emphasis on building releasable software in short time periods. Agile development differs from other development models: in this model time periods are measured in weeks rather than months and work is performed in a highly collaborative manner. Most agile methods also differ by treating their time period as a strict timebox.
Contrasted with the waterfall model
Agile development has little in common with the waterfall model. As of 2009, the waterfall model is still in common use.The waterfall model is the most structured of the methods, stepping through requirements-capture, analysis, design, coding, and testing in a strict, pre-planned sequence. Progress is generally measured in terms of deliverable artifacts: requirement specifications, design documents, test plans, code reviews and the like.
The main problem with the waterfall model is the inflexible division of a project into separate stages, so that commitments are made early on, and it is difficult to react to changes in requirements. Iterations are expensive. This means that the waterfall model is likely to be unsuitable if requirements are not well understood or are likely to change in the course of the project.
Agile methods, in contrast, produce completely developed and tested features (but a very small subset of the whole) every few weeks. The emphasis is on obtaining the smallest workable piece of functionality to deliver business value early, and continually improving it and adding further functionality throughout the life of the project.
In this respect, agile critics may assert that these features are not placed in context of the overall project, concluding that, if the sponsors of the project are concerned about completing certain goals with a defined timeline or budget, agile may not be appropriate. Proponents of agile development counter that adaptations of Scrumshow how agile methods are augmented to produce and continuously improve a strategic plan.
Some agile teams use the waterfall model on a small scale, repeating the entire waterfall cycle in every iteration.Other teams, most notably Extreme Programming teams, work on activities simultaneously.
Contrasted with "cowboy coding"
Cowboy coding is the absence of a defined method: team members do whatever they feel is right. Agile development's frequent re-evaluation of plans, emphasis on face-to-face communication, and relatively sparse use of documents sometimes causes people to confuse it with cowboy coding. Agile teams, however, do follow defined (and often very disciplined and rigorous) processes.
As with all development methods, the skill and experience of the users determine the degree of success and/or abuse of such activity. The more rigid controls systematically embedded within a process offer stronger levels of accountability of the users. The degradation of well-intended procedures can lead to activities often categorized as cowboy coding.
Suitability of agile methods
There is little if any consensus on what types of software projects are best suited for agile methodologies. Many large organizations have difficulty bridging the gap between a more traditional waterfall method and an agile one.
Large scale agile software development remains an active research area.
Agile development has been widely documented (see Experience Reports, below, as well as Beck pg. 157, and Boehm and Turnerpg. 55-57) as working well for small (<10>
Some things that can negatively impact the success of an agile project are:
- Large scale development efforts (>20 developers), though scaling strategies and evidence to the contrary have been described.
- Distributed development efforts (non-co-located teams). Strategies have been described in Bridging the Distance and Using an Agile Software Process with Offshore Development
- Command-and-control company cultures
Agile home ground:
- Low criticality
- Senior developers
- Requirements change very often
- Small number of developers
- Culture that thrives on chaos
Plan-driven home ground:
- High criticality
- Junior developers
- Requirements don't change too often
- Large number of developers
- Culture that demands order
Agile methods and method tailoring
In the literature, different terms refer to the notion of method adaptation, including ‘method tailoring’, ‘method fragment adaptation’ and ‘situational method engineering’. Method tailoring is defined as:
Potentially, almost all agile methods are suitable for method tailoring. Even the DSDM method is being used for this purpose and has been successfully tailored in a CMM context.Situation-appropriateness can be considered as a distinguishing characteristic between agile methods and traditional software development methods, with the latter being relatively much more rigid and prescriptive. The practical implication is that agile methods allow project teams to adapt working practices according to the needs of individual projects. Practices are concrete activities and products that are part of a method framework. At a more extreme level, the philosophy behind the method, consisting of a number of principles, could be adapted (Aydin, 2004).A process or capability in which human agents through responsive changes in, and dynamic interplays between contexts, intentions, and method fragments determine a system development approach for a specific project situation.
Agile beyond software development
Criticism
Extreme Programming's initial buzz and controversial tenets, such as pair programming and continuous design, have attracted particular criticism, such as McBreen and Boehm and Turner.[14] Many of the criticisms, however, are believed by Agile practitioners to be misunderstandings of agile development.
In particular, Extreme Programming is reviewed and critiqued by Matt Stephens's and Doug Rosenberg's Extreme Programming Refactored.
Criticisms include:
- Often used as a means to bleed money from customers through lack of defining a deliverable
- Lack of structure and necessary documentation
- Only works with senior-level developers
- Incorporates insufficient software design
- Requires meetings at frequent intervals at enormous expense to customers
- Requires too much cultural change to adopt
- Can lead to more difficult contractual negotiations
- Can be very inefficient—if the requirements for one area of code change through various iterations, the same programming may need to be done several times over. Whereas if a plan were there to be followed, a single area of code is expected to be written once.
- Impossible to develop realistic estimates of work effort needed to provide a quote, because at the beginning of the project no one knows the entire scope/requirements
- Can increase the risk of scope creep due to the lack of detailed requirements documentation
- Agile is feature driven, non-functional quality attributes are hard to be placed as user stories
The criticisms regarding insufficient software design and lack of documentation are addressed by the Agile Modeling method, which can easily be tailored into agile processes.
Agile software development has been criticized because it may not bring about all of the claimed benefits when programmers of average ability use this method.
http://agilealliance.org/system/article/file/904/file.pdfJumat, 06 Maret 2009
tugas otomotif
2. Komputer Mobil
Perangkat keras utama dalam sistem ini adalah central processing unit (CPU). Untuk mempermudah pemasangan digunakan casing produksi Trivia yang sama dengan standar perangkat audio di mobil (berukuran 1 din, lebar 17,78 cm dan tinggi 5,08 cm), sehingga tidak perlu dilakukan banyak modifikasi interior mobil
Motherboard yang digunakan berukuran Mini-ITX (17 cm x 17 cm). Untuk mengurangi panas, dipilih motherboard kecepatan sedang, yaitu VIA EPIA M6000, menggunakan processor VIA Eden 600 MHz, sudah cukup andal menjalankan aplikasi-aplikasi berbasis Windows XP.
Untuk media penyimpanan, digunakan harddisk 40 GB 2,5 inci, yang didesain lebih tahan guncangan dibandingkan harddisk biasa berukuran 3,5 inci. CPU ini juga dilengkapi dengan pemutar DVD.
(Kutipan dari : subaridargombez.wordpress.com)
Perangkat keras utama dalam sistem ini adalah central processing unit (CPU). Untuk mempermudah pemasangan digunakan casing produksi Trivia yang sama dengan standar perangkat audio di mobil (berukuran 1 din, lebar 17,78 cm dan tinggi 5,08 cm), sehingga tidak perlu dilakukan banyak modifikasi interior mobil
Motherboard yang digunakan berukuran Mini-ITX (17 cm x 17 cm). Untuk mengurangi panas, dipilih motherboard kecepatan sedang, yaitu VIA EPIA M6000, menggunakan processor VIA Eden 600 MHz, sudah cukup andal menjalankan aplikasi-aplikasi berbasis Windows XP.
Untuk media penyimpanan, digunakan harddisk 40 GB 2,5 inci, yang didesain lebih tahan guncangan dibandingkan harddisk biasa berukuran 3,5 inci. CPU ini juga dilengkapi dengan pemutar DVD.
(Kutipan dari : subaridargombez.wordpress.com)
Novianty gustiana
07044411072
Tek.informatika smstr4
Lebah Madu dan Keajaiban Arsitektural Sarang Madu
Lebah menghasilkan madu lebih banyak daripada yang dibutuhkannya dan menyimpannya di sarang. Semua orang sangat mengenal struktur heksagonal sarang lebah. Pernahkah Anda bertanya-tanya mengapa sarang lebah berbentuk heksagonal, bukan oktagonal atau pentagonal?
Para ahli matematika yang mencari jawaban pertanyaan itu mencapai kesimpulan menarik: "Heksagon adalah bentuk geometri paling tepat untuk penggunaan maksimum suatu ruang."
Sel berbentuk heksagonal membutuhkan jumlah lilin minimum, tetapi mampu menyimpan madu dalam jumlah maksimum. Jadi, lebah menggunakan struktur sarang yang paling tepat.
Metode yang digunakan untuk membangunnya pun sangat menakjubkan: lebah-lebah memulainya dari dua atau tiga tempat berbeda dan menjalin sarang-nya secara serentak dengan dua atau tiga deretan. Meskipun memulai dari tempat yang berbeda-beda, lebah yang jumlahnya banyak ini membuat heksagon-heksagon identik, kemudian menjalinnya jadi satu dan bertemu di tengah-tengah. Titik-titik sambungnya dipasang dengan begitu terampil sehingga tidak ada tanda-tanda telah digabungkan.
Melihat kinerja luar biasa ini, kita harus benar-benar mengakui kehendak agung yang mengatur makhluk-makhluk ini. Tetapi evolusionis menjelaskan prestasi ini dengan konsep "insting" dan mencoba mengajukannya sebagai sifat sederhana pada lebah. Namun, jika ada insting yang ber-peran mengendalikan semua lebah dan kalaupun semua lebah bekerja dengan harmonis walau tanpa saling bertukar informasi, berarti ada suatu Kebijakan Agung yang meng-atur seluruh makhluk kecil ini.
(Kutipan Dari : http://www.evolutiondeceit.com/indonesian/keruntuhan17.php)
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