Design and simulation of silicon optoelectronic integrated circuits

Advances in optical data storage technology have been so rapid over the past several decades for a wide range of PC and consumers electronics applications. In this new millennium, the BD (blu-ray disc) technology, the next generation to CD and DVD, using blue laser light (405nm) was introduced recently. BD technology is superior to first two generations for its higher storage capacity, usability for data storage and high-definition content delivery and backward compatibility. A main component of the blu-ray disc system, the optical pick-up unit (OPU), requires a PDIC (photodetector integrated circuit) consisting of photodetector and preamplifier. In this final year project, two main components of PDIC used in optical pick-up unit of blu-ray disc system, photodiodes and preamplifiers consisting of transimpedance amplifier(TIA) and limiting amplifier(LA), has been designed and simulated. During the project, the student learned the overview of optical storage device systems and theory of transimpedance amplifier and limiting amplifier and design and process of photodiodes. The TIA and LA have been designed using the TSMC 0.18 um CMOS technology in the Cadence Virtuoso Custom Design Platform. A bandwidth of TIA is larger than 2.02 GHz and a gain of 77dB have been achieved, and after integrated with limiting amplifier, the bandwidth is around 10GHz and the output voltage has reached to more than hundreds with the input current signal of about 1uA. After that, the fabrication ready layout of TIA circuit with photodiodes and metal pads and limiting amplifier circuit have also been generated. Besides, the various designs of photodiodes are designed and simulated in Taurus Tsuprem4 and Medici. The complete fabrication steps have been simulated with the variation in process parameters and device structures. Furthermore, the current-voltage behaviors, transient behavior and frequency response have also been obtained from device simulation. The effects of substrate doping and device structure have been studied. The suggested improvements and works are also provided for the further development.Bachelor of Engineerin

Online Buying in Virtual Cosmetic Marketplace Using Recommender System

Electronic Commerce (E-commerce) has become one of the essential characteristics in the Internet era. Nowadays, E-commerce is growing rapidly in the Internet, and has become a complement to the usual business activities of corporations and individuals. Recommender systems have evolved in the last years as specialized tools to assist users in a plethora of computer-mediated tasks by providing guidelines or hints. Most recommender systems are aimed at helping users to deal with the problem of information overload by facilitating access to relevant items.In this system, shopping agents like buying agents, selling agents, and mall agents, and then knowledge-based recommender system are used because the World Wide Web information grows explosively in the Internet and people encounter problem to pick some correct things from the set of choice in E-Commerce. All the activities are done in Virtual Marketplace. Virtual Marketplace is a type of E-Marketplace system. In this system, recommender systems help users choose something they actually want or need and limit their search by supplying a list of items. Therefore, the recommender systems get vital role in the Internet. The objective of the system is to give effective products for user when they want to search cosmetic as to which type of cosmetic is suitable for them. Knowledge-based recommender system and implementation with a multi-agent system framework for marketplace system are used in this system, in which buying agent, selling agent and mall agent are presented

Factors Influencing Proper Plantar Ulcer Care of Leprosy Patients: Experience from Mon-Ywa Township of Disabilities Survey Project, Myanmar

A cross-sectional study design was applied to explore types and ways of proper plantar ulcer care and factors influencing it. This study was conducted during 2008 in Mon-ywa Township because it is one of the ‘9 selected townships of the Disabilities survey project’. The study involved 19 patients affected by leprosy (PAL) with foot grade 2 disability, but without plantar ulcer at the time of study, 6 community members who had PAL in their immediate family and 6 community members who had PAL among their surroundings. They participated voluntarily in the study. The information was gathered by in-depth interview. Stigma attached to disability-related leprosy was still observed among the study respondents. They knew that ulcer could weaken their life and their surroundings. They were also aware of that one would gain benefit if one would free from ulcer. Personal outlook, a close attachment of their families and responsibility for the family, community’s reactions and the provision from the health service were the key factors to push and pull the PAL to perform plantar ulcer care. Consequently, as to regain the normal life in a society, despite a number of difficulties, PAL tried their best to look after the plantar ulcer along with the help from their families and relatives. As they were aware of the value of ulcer-free condition. for the future, they had positive view on plantar ulcer care not only for them but also for their families