Monday, August 25, 2008

Country I have visited



create your own visited country map

Sunday, August 17, 2008

Learning Korean language and culture through Korean proverbs and idioms

One day my advisor professor told me that Mr. Josh - 서당개 삼 년에 풍월 읊는다. He explained me the Korean proverb (속담) in English after he said in Korean. (After three years at Sodang (community school for children), even a school's dog can chant Chinese lessons.) He yelled at me to inspire me to learn Korean language when he saw a guy from my country was giving interview in Korean to the TV journalist in alumni association’s party. I liked the proverb but could not remember at that time but it struck my mind and I wanted to remember that proverb. I came back to my lab and ask my lab mate to repeat that proverb and then I remembered.

I used to remember Korean proverbs/quotes and use while speaking to Korean friends. They also inspired me to learn more proverbs. Actually, I wanted to learn Korean values and culture through Korean proverbs. In fact, learning proverbs is a way to be able to identify specific Korean customs. Further it helps us to find similarities and differences between Korean customs and my own county’s customs. Korean proverbs are direct reflections of wisdom, morals, and customs of Koreans. Even though some of the proverbs are handed down for hundreds years, morals and values are still intact in modern Korean life. The following proverbs are examples that teach us important issues in everyday life and appropriate behaviors that are required in Korean society.

I even tried to remember messenger tag line of Korean friends. I like learning Korean proverbs and idioms for many reasons. One of the main reasons was to improve my Korean vocabulary. Improving vocabulary by hitting the book is more stressful and we cannot enjoy the words.

These days I feel more comfortable to use Korean proverbs and Idioms. I want to use those in my everyday speaking. It is easy to talk to Korean friends using those proverbs and idioms. These Korean proverbs cannot be translated directly (even in other words in some cases) in English, even in my native language. When I try to translate, I feel the soul of the idioms or proverbs died.

I believe that these inspirational quotes and proverbs give sprits and say 화이팅 to them. As Wolfgang Mieder gave the definition of proverbs “Proverbs are short, generally known sentences of the folk that contain wisdom, truths, morals, and traditional views in a metaphorical, fixed and memorizable form and that are handed down orally from generation to generation.”

Some of the proverbs are more inspirable to the researchers. When I feel tired with everyday study I remember these inspirable proverbs. 호랑이 굴에 들어가야 호랑이를 잡는다. To write good paper you have to work hard and overcome the difficulties. 하늘이 무너져도 솟아날 구멍이 있다. Even if the sky falls on you, there is a hole from which you can escape.

The other popular way to make many friends and improve Korean language is learning idiom. Korean idioms are really funny, meaningful, and tremendous. For example, when my Korean friends ask me to go for 불닭 (very spicy barbecued chicken), I say 아니요, 입에서 불이 난다! (Oh no! fire comes out from mouth). When I say this idiom to my friends, they give me a great smile and I find myself more intimate to them. Similarly, when I go to drink outside with my friends, I usually say 죽을 때까지 마서.


Finally, check this also...

Saturday, August 16, 2008

Mythical founder of Korean race

According to the Korean 신화 (myth), a tiger and a bear wanted to become humans. The god told them to stay in a cave for a hundred days eating only garlic. The bear stayed long enough and become a woman but the tiger could not wait. Later the bear became a woman and married the god's son. She gave birth to a son, who is mythical founder of Korean race, Tankun.

Hard to get H1B visa

Wednesday, August 13, 2008

How to fill patterns in MS Excel 2007 Graph?

I am using MS-2007. Today I was making graph for my research paper. I wanted to fill patterns because I have to print it in B/W ink. I tried hard to find it hard in MS Excel 2007 but couldn’t find it. I don’t know why they excluded it. 
I found a link written how to make UI in this blog http://blogs.msdn.com/excel/archive/2007/11/16/chart-pattern-fills.aspx . It’s good. 

I found one another free UI addin to fill pattern. I tried it, it works fine. The link of that site is http://www.andypope.info/charts/patternfills.htm .

Saturday, July 26, 2008

WiBro vs. WiMAX

WiMAX, is an acronym of Worldwide Interoperability for Microwave Access, is a telecommunications technology provides wireless data over long distance. It is based on the IEEE 802.16 standard, also called WirelessMAN. According to WiMAX forum WiMAX is a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL.  

WiBro (Wireless Broadband) is a wireless broadband Internet technology being developed by the South Korean telecoms industry. WiBro is the South Korean service name for IEEE 802.16e (mobile WiMAX) international standard. Actually, WiBro was developed to overcome the data rate limitation of mobile phones (for example CDMA 1x) and to add mobility to broadband Internet access (e.g. ADSL or Wireless LAN). WiBro adapts TDD for duplexing, OFDMA for multiple access and 8.75 MHz as a channel bandwidth. WiBro base stations offer an aggregate data throughput of 30 to 50 Mbit/s and cover a radius of 1-5 km allowing for the use of portable internet usage. It provides mobility for moving devices up to 120 km/h.

Advantages of WiBro over WiMax:

WiBro provides mobility for moving devices up to 120 km/h compared to WLAN having mobility up to walking speed and Mobile Phone having mobility up to 250 km/h. It also offers QoS. The inclusion of QoS allows for WiBro to stream video content and other loss-sensitive data in a reliable manner. 

Friday, July 25, 2008

A sensor network which covers 2 Km x 2 Km to measure a temperature, humidity and CO2 levels every 10 seconds.


We design a sensor network that collects data monitoring temperature, humidity and CO2 levels. The sensors in 2x2 Km2 area relays collected data to its neighboring sensors and then to a base node. Base node is connected with computer that processes and analyzes data. We selected following factors to design the network

Sensor Nodes (Motes): Crossbow Berkeley Motes may be the most versatile wireless sensor network devices in the market commercially available. MICAz is the latest generation of Motes from Crossbow Technology. MICAz motes come with several sensors installed - Temperature, Humidity, Gas, Light, Acceleration/Seismic, Vibration etc. Different sensors can be installed if desired. The MPR2400 (2400 MHz to 2483.5 MHz band) uses the Chipcon CC2420, IEEE 802.15.4 compliant, ZigBee ready radio frequency transceiver integrated with an Atmega128L micro-controller. 51 pin I/O connector, and serial flash memory is used. Alternatively, USS 2400 marketed by a Korean Company HUINS (Human Intelligent System) can be used. USS 2400 is compatible with Berkeley Motes. 
These motes are low power and small physical size enable placement virtually anywhere. Since all sensor nodes in a network can act as base stations, the network can self configure and has multi-hop routing capabilities. 

Number of Nodes required: We can apply a grid structure to uniformly deploy sensors. MICAz’s maximum transmission range is 100m in open air. However it is always safe to use  N= Gx × Gy = X/r × Y/r

=(2000 m)/(50 m)×(2000 m)/(50 m)=1600

Where, Gx and Gy are the total number of grids in X and Y respectively. r is a transmission range of the node (transmission range is given as 50 m). Above calculation shows total number of nodes required is 1600. 


Base Stations: A base station allows the aggregation of sensor network data onto a PC or other computer platform. According to our network plan at least one Base Station is required. Any MICAz Mote can function as a base station by plugging the MPR2400CA Processor/Radio Board into an MIB510CA serial interface board. The MIB510CA provides an RS-232 serial interface for both programming and data communications. 

Computer (PC): We need at least one computer for data aggregation, processing and analysis. Any latest version of readily available computer can be used for this purpose. Better and dedicated server can be considered according to the significance of the data.

Routers: As we implement AODV (Ad Hoc on Demand Distance Vector) routing protocol we do not need dedicated router. It is an ad hoc structure i.e. any normal sensor node (MICAz mote) in the network can be a router. 

Battery Power : MICAz form factor is designed to match up with two AA batteries; however any battery combination (AAA, C, D, etc., cells) can be used provided that the output is between 2.7 VDC to 3.6 VDC.

Softwares: 
OS: Freely available and open source, TinyOS has become the de facto industry-standard operating system for sensor network research and applications. A researcher’s group from UC Berkeley designed this sophisticated operating system to manage mote hardware. TinyOS is written in nesC. nesC supports the event-driven processing that is typical of motes, which remain "asleep" until sensors acquire data or receive messages. 

Protocols: 
MAC: We use S-MAC as a MAC layer protocol. S-MAC protocol is designed for wireless sensor networks. S-MAC uses three novel techniques to reduce energy consumption and support self-configuration. To reduce energy consumption in listening to an idle channel, nodes periodically sleep. Neighboring nodes form virtual clusters to auto-synchronize on sleep schedules. S-MAC applies message passing to reduce contention latency for sensor-network applications that require store-and-forward processing as data move through the network. 

Routing: Our network design is static or barely dynamic in nature. AODV (Ad Hoc on Demand Distance Vector) routing protocol can be used. AODV routing algorithm is an on demand algorithm, it is loop-free, self-starting, and scales to large numbers of nodes. AODV builds routes using a route request / route reply query cycle. If any link is broken in the link it repairs using route error message.