DATA MINING

The presentation was conducted jointly between Joshua Shendu and Remy Kaaro, The presentation was well planed and presented by the all presenters because it was well understood and interesting. The lesson was aimed at giving the awareness to all students on how they can get and give varieties of information to other people. Now, data mining is the process of extracting the hidden patterns from large amount of data. As the words themselves are in relation to minerals, people have been manually extracting the information from data for centuries but the data are increasing arithmetically hence they are in need of modern methods of extracting those in formations, which is known as automatic approaches.
The data mining can be categorized in several forms, which are relational database and social network data mining. This involves the mining of data that has good relationship in the database. Text mining this involves the finding of the written information on different documentary places. Audio mining involves the finding of information, which is in sound form. Video data mining are data finding which are in animated pictures are is motion. Image data mining is the finding of information that are extracted from the images. Web data mining is the mining is the search of information, which are found in the WebPages.
The very important part was the analysis of three stages of data mining which is the exploration of the information. This stage starts with the data preparation that also involves the cleaning of data and data transformation. The second stage is the Model building and validation, this is the very important part where the data user get confirmation on the validity of those information, also choose the best one based on their predictive performance. Third is the deployment, this is the final stage which involves using the model selected as best in the previous stage and applying it to new data in order to generate predictions or estimates of the expected outcomes.
Moreover the presentation covered on the advantages of data mining which started that are used by marking different achievements which reached by a certain integrated projects. Banking systems are the most stakeholders of the data mining activities for search the nature and type of customs they could have in different societies. The law enforcing organs are also using the data mining for security purposes e.g. police military and other of the like. Researchers are also using the data found in the system and adding more information in the inventory.
Further more they presented the disadvantages of data mining where they analyzed about security issues where some information can be licked to the sabotage groups like criminal groups. The misuse of the information where some of the information is privacy the expose of that information is not putting some people in harmonious situation.

IMAGE COMPRESSION



Introduction:
· Concept of image compression;
· Data compression is the technique that is used to reduce larger data files into smaller file size.
· Images compression is the action of reducing the size of image by increasing its firmness or compactness as with the aim of reducing the space.

·Historical background of image compression.
The historical background of image compression started to become a challenge when digital images were supposed to be transferred from one point to another. In digital image data it is important to reduce the amount of information by using a sparse representation of the image. This is to be done in a very systematic way so as at least to main its quality as not deform its original shape and quality.
The performance of any image compression scheme depends on its ability to capture characteristics features of such image, such as sharp edges and fine textures, while reducing the number of parameters used for its modeling.


· Importance of image compression.
(i). Makes transfer of images through network faster.
(ii).Maximizes space for storage of data images.
(ii). Saves space in storage devices.
(iii). It saves time for image downloaded

· Types of image compression are categorized into:
o Lossless – Compression technique that retains all its original data, such as there is no loss of data after being compression. The size of the file is a bit larger in size if compared to lossy technique and also have better image quality compared to lossy technique.
oLossy – Compression technique in which there is a permanently loss of data after being compressed. Data image can not be decoded to original format and have the same quality. In this technique the fill can have smaller size compared to Lossless technique, also the quality of picture has slightly lower quality compared to lossless.

· There many images format, these are some of image format that are widely used:-
o TIFF (Tagged Image File Format).
o JPEG (Joint Photographic Experts Group).
o GIF (Graphical Interchange Format).
o PNG (Portable network graphics).
o BMP (Bitmap).
o PSD (PhotoShop Document).

· There are many types of images such as:-
DCT is the technique for converting signal into elementary frequency components.
(a). DCT- based image compression relies on two techniques to reduce the required
data to represent the image. These are:-
o Quantization-The process of reducing the numbers of possible value of a quantity thereby reducing the number of bit needed to represent it.
o Entropy coding-Is the technique for representing the quantized data as compactly as possible.

· Tools for image compression.
The tools that can be used in image compression vary from free source to proprietary. Such tools includes;- GIMP free source software, Adobe Photoshop and JPG-seizer.

· Important tips when compressing image:
· In compressing an image, start from the original image since compression from compressed image leads to poor image quality.
· Do not save to the new format if you think you need to still proceed in compressing and image.

· Advantages of image compression includes:-
o To Reduce the data storage requirements
o To Reduce the time for images downloaded
o For E-mail attachment
o For use in Web pages
o In Photo sharing websites

· Disadvantages of image compression.
o Reduce reliability of image records
o Reduction of information or bits
o Time consuming.
o Disruption of data properties

Conclusion;.
The image compression is very important in IT technology regardless of few discussed disadvantages that is having.

USABILITY ENGINEERING AND HUMAN COMPUTER

OBJECTIVES
A.INTRODUCTION
B.HISTORICAL BACKGROUND
C.WHY USABILITY ENGINEERING AND HUMAN COMPUTER INTERACTION
D.HOW USABILITY CAN BE ACHIEVED
E.CHALLENGES
F.FUTURE
G.CONCLUSION


INTRODUCTION
-Usability engineering (UE):
Is the techniques of developing a system which is interactive, usable or meets the needs of users.
-Human computer interaction (HCI):
Is the discipline which deal with the study of interaction between users and computers.

-Usefulness:
*For an interactive system to be useful it should be goal centred.
-Usability:
*Is a system that takes account of users’ capability, limitations and needs .
Example
*The use of cork-screw for opening bottles sealed with cork.


HISTORICAL BACKGROUND
-Around 1945 people were studying ergonomics(efficiency) of machines.
-E.g. ergonomic society of UK was found in 1949.
-In 1960,s most computer software and hardware users were computing professionals.
-In 1970’s the computer users were diverse so came a need of human interactive system.
-HCI has developed into a discipline or field in its own right over the last ten years or so.


WHY UE AND HCI?
-Increases the productivity-as its work force is more productive
-Decrease training and supportive costs.
-Increase the customer satisfaction and decreases technophobia.
-Reduces disastrous and fatal errors in the system which are safety-critical.
Example.
Aircraft which has all its documentation online can cause accident if its interface is not clear.


HOW UE AND HCI CAN BE ACHIEVED
-Approaches of designing products
*Product-centred design
*User-centred design

PRODUCT-CENTRED DESIGN
&Is the production process which does not take an account of the user’s needs.
* Assumptions of the product centered design
-The result of a good design is having a product working.
-The product’s specifications are derived from the customer.
-There’s no further contact until delivery.


PROBLEMS
*Lack of user involvement caused problems such as;
*Products were not useful or usable.
*Eventually the product-centered approach was abandoned.

USER-CENTRED DESIGN
&Is the design practice which is rooted in the idea that user must take center -stage in the design of any computer system.
-precisely to make human being a focal point that technology should serve rather than the other way round

*Assumptions of the user centered-approach:
-The result of a good design is a satisfied user.
-The process of design is a collaboration between designers and users.
-User and designer are in constant communication during the entire process


Criteria of user-centred approach.

*Learnability-refer to how easy it is to learn to use the product.
*Efficiency-refers to how supportive the product is in carrying out a certain task.
*Memorability - refer to how easy it is to remember how the system is used once it has been learned.
*Safety-Protecting the user from dangerous and undesirable situations.
*Entertaining-if a product was for entertainments then it has to reach that goal. *Motivating- the product made should encourage the user to continue working with it.
*Visibility-links in the interface has to be clearly visible.
*Affordance- the price of the product should relate to the income of the society.
*Feedback- the interface has to respond on whatever is done and give right suggestions.
*Colour- Product should take an account of colour psychology.

CHALLENGES
*Hard to get requirements from users who have no technique expertise.
*Due to technological advancements, the societies’ needs varies with time.
*Large amount of fund is need in the development of new product.
*Difficult to build a system which can suit all types of users and their needs.

FUTURE
*Computes are too cumbersome and unwieldy tools. We need a small and specific appliances for specific jobs.
*Decreasing costs but increaced efficiency of products.
*Increasing innovation in input techniques (i.e., voice, gesture, pen).
*Increasingly widespread use of computer to different groups of people who are outside of the computing profession.
*Wider social concerns leading to improved access to computers by currently disadvantaged groups.

CONCLUSION
-UE and HCI is all about to impart,
*Designers,
*Developers and
*Implementers ;
with the necessity of usefulness and usability of the products which in turn will bring about good functionality, high efficiency and eventually increased productivity of the products or machines.


References
-Andrew S, et al.(2008).The human- computer interaction handbook: Fundamentals evolving technologies.
-Stuart C, et al. (1983). The Psychology of Human-Computer Interaction.
-Brad A, et al (1998).A belief History of Human-Computer Interaction Technology.
-Don Norman, (1998).The Invisible Computer; Cambridge MA, MIT press
-www.pure usability.co.uk/File/ISO13407.png

THE RESEARCH FIELD IN COMPUER SCIENCE

This is the course which is to be undertaken by this second semister by all first years. I think the course will equip we as first years with the research tools which will us in future career in research field.