Cloud Computing

Poon Kwok Huen

Introduction
Cloud computing is a very popular concept applied in many internet websites and applications like Google and Facebook, but it seems that not many people what cloud computing is. Through cloud computing, users can just use their phones to connect to the internet and access software, platform and hardware provided by many other computers that are also connected to the internet. We can also perform computation of very large programs which even supercomputer takes time to solve with cloud computing.

Definitions
Actually, cloud computing is not a new technology, but only a concept about delivery of resources on internet. We can find many definitions of cloud computing on the internet and we may not have a clear idea about cloud computing, but we can still conclude some common characteristics and applications about cloud computing.

Cloud computing is to access internet resources by the users’ own internet devices and make use of the resources to do tasks. As internet is a very big collection of computers, cloud computing can also be described to be using the software and hardware resources of the other computers through internet. As we can gather the power of a large number of computers, we can perform powerful computing or provide computing services through internet.

Characteristics
In real life situation, cloud computing is used by large companies for delivering their services. They set up many powerful servers and develop applications for users to access, with some are charged and some are free of charge. This kind of service shares 3 properties:

1. The service is charged according to the amount of resources used, like the amount of time using the online service of the computation power used by the servers.
2. Users can use and cut the service as they want to, as well as they have no time limit or specified period. The providers put the services on their platform and users can use the service as they pay the required charge or cut the service by stop accessing the service.
3. The services provided are totally maintained by the providers, which are the companies. As the resources such as software and hardware are all owned by the companies, the companies are responsible to maintain the functionality of the resources so to maintain stable services.

These services are divided into 3 main types: Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS).

Software-as-a-Service (SaaS)
SaaS is to provide software for user to use online. Originally, individual users or companies need to buy the license of software for several years in order to use the software, and they can install the software at their computer to do their tasks. Now cloud computing allows the user to use the software on demand. The software is installed in the providers’ servers. When the user wants to use it, they can connect to the providers’ servers and use the software online. It can reduce the cost of the software for users in a small scale, and the software is kept to be the most upgraded version. Also, the requirement of hardware for the users’ computers is not high as they just need their device to connect to the computer, operate the software and receive the result, but not computing the content. Nowadays SaaS is focusing on commercial software, and some companies such as Salesforce are fighting for the SaaS market.

Platform-as-a-Service (PaaS)
PaaS is to provide a platform, including a set of software on an API, website portals or gateway software, for users to develop their own set of programs on the platform. As a result, PaaS is an entire service for users to develop their own software which fits them most. Also because the users develop the PaaS, it helps the improvement of PaaS and SaaS, creating more functions and applications for the platform. For example, Google provided the Google App Engine in 2008 for users to develop their apps, which is also a typical case of PaaS.

Infrastructure-as-a-Service (IaaS)
IaaS is to provide users with all the server resources, including start, stop, access, configure, storage, computing power, internet service and software. It is just like using a virtual machine online and you can do whatever you want. Base on the concept of on demand, a user can just use what he or she needs and leaves the other resources, so that the other resources for other usage. The most famous IaaS provider is Amazon EC2, which start running from 2006 and provide virtual machine with different configurations.
 

Conclusion
There are still many probabilities for cloud computing. The characteristics, definition and common service form stated above are just some brief introduction about the situation and application of cloud computing and the whole world is still looking forward to how cloud computing can lead the development of the commercial world, electrical world and our living standard.

References

1. “What is Cloud Computing?” http://searchcloudcomputing.techtarget.com/

Education using computer games

Nowadays, playing computer games is a very common form of entertainment for wide range of people (Nippold, Duthie, & Larson, 2005). No matter they are children, teenagers, adults or elderly, computer games are not something new to them. Some very simple computer games are already embedded as utility programs in the Microsoft Windows. Those are some housewives’ favour. Obviously, computer games have involved in most people’s daily lives. This essay is going to discuss about the nature and the impact of computer games in the education aspect.

Computer games are widely used as a tool in education in different categories. They can be used in school for teaching purpose, in health and physical education or even in personal development. Those computer games for educational purpose are called educational computer games, which is not only about entertainment but also includes education (Prensky, 2001). Therefore, educational computer games are quite different from traditional computer games which are mainly for entertainment.

One of the most common areas for applying educational computer games is in school. Due to the popularity of personal computers and Internet services, educational computer games are introduced into schools. Students can learn different subjects through playing some computer games. Students can easily reach the games through Internet or the CD-ROM from the publisher. This form of education is much attractive to the students and it can have positive impact on student’s educational effectiveness and motivation (Papastergiou, 2008). Many of the primary school and high school textbooks are accompanied with CD-ROMs which contain some interactive computer games to help students to understand the lessons better. According to a research by Papastergiou (2008), a digital game-based learning mode was applied to a high school computer science education. The results show that the specially designed educational computer games can help the students to learn better. Computer game based learning is much interesting to students. They are much more willing to learn and much easier to remember. In this area, computer games are not only about entertainment, they are also education and beneficial to the students.

Apart from the application of computer games in schools, it is also introduced to the public for health and physical education. Usually, the computer games only require players to respond to the games by pressing buttons. It may cause may health problems, likes obesity. Fiorentino-Holland and Gibbone (2005) introduce Virtual Gym to the public, which can simulate real situation. Players have to respond by performing physical actions rather than only pressing some buttons. Some people, especially children, are more willing to do exercise through computer games. It is more funny and attractive. This kind of games can really help the over-weight children to lose the weight and also help students to understand health-related fitness concept (Papastergiou, 2009). This kind of application requires the combination of computer games with a set of physical exercise. It is not only about excitement but also about how to keep the player healthy.

Education is not only about academic, but also about personal development. Besides academic learning, health and physical education, computer games can also help the personal development of students. A program was established in Scotland which aimed to develop children as successful learners through computer game design (Robertson & Howells, 2007). A class of ten years old children designed a computer game in eight weeks. The result of the program shows that the children become more enthusiastic and motivated for learning (Robertson & Howells, 2007). They also learn to determine to reach high standards of achievement, learn as independent and group learners and learn to link and apply learning in new situations (Robertson & Howells, 2007). It is difficult to learn these things in school through traditional teaching, but students can learn all these things deep in mind through designing computer games.

In the past, playing computer games was only a very popular free-time activity for people (Nippold, Buthie, & Larson, 2005). However, computer games are not only for entertainment now, it can be educational. Computer games can be a helpful tool in education. They provide interactive learning platforms to facilitate people’s learning. They can also help health and physical education and also help personal development. Computer games can combine with many other things for different purpose. It is a very useful tool. In the future, computer games may have much broader applications to benefit us.

Reference

1. Nippold, M., Duthie, J., & Larson, J. (2005). Literacy as a leisure activity: Free-time preferences of older children and young adolescents. Language, Speech and Hearing Services in Schools, 36(2), 93–102.
2. Prensky, M. (2001). Digital game-based learning. New York: McGraw-Hill.
3. Papastergiou, M (2008). Digital Game-Based Learning in high school Computer Science education: Impact on educational effectiveness and student motivation. Computers & Education, 52, 1-12.
4. Fiorentino-Holland, L., & Gibbone, A. (2005). Using the Virtual Gym for practice and drills. Teaching Elementary Physical Education, 16(5), 14–16.
5. Papastergiou, M. (2009). Exploring the potential of computer and video games for health and physical education: A literature review. Computer & Education, 53, 603-622.
6. Robertson, J., & Howells, C. (2007). Computer game design: Opportunities for successful learning. Computer & Education, 50, 559-578.

Quantum computer

Comment:

What makes a quantum computer impractical?

Follow-up:

For now, the greatest difficulty is in the implementation of a quantum circuit that is stable. In fact, the problems related to accurately and reliably measuring the quantum bits, namely de-coherence and error correction, are still very difficult to solve in practice, even if we assume we can deploy tremendous amount of resources at the construction of a quantum computer.

Still remember the chaotic theory? It is also anticipated that if we cannot tackle the accurate measurement problem effectively, it would be impossible to scale up the size of a quantum circuit without leading to enormous errors.