RESEARCH EXPERENCE
1. Regulatory System Simulation in ECOPHYS Model
It is part work of the ECOPHYS model which simulate the tree growth. This ECOPHYS project is sponsored by Natural Resources Research Institute, University of Minnesota-Duluth. The Regulatory System Simulation I am working with is to simulate some effect of external factor to the tree growth, such as the temperature, carbon-dioxide density, light intensity, etc. All the program is written in VC++ 6.0, and every program which simulate the regulatory system functions works as a server and was written as COM object.
2. Data Collecting and Distributing System
It was written by UNIX C++. This program works as a intermediate server in a data exchange system consist of a cluster computers running Windows 95, NT, and UNIX, which are connected by Internet, using TCP/IP protocol. DCDS consists two parts, (1) Collecting part: generate a receiving process for each request coming from data source, then send the data received to the queue. (2) Distributing part: send to data from the queue to the destination, according to the information contained in the data.
3. Automatic Semaphore Failure Detection System
A project sponsored by Railway Ministry of P.R.China. The basic system consists of a Base station and a cluster of mobile detection boxes, each one is installed on a locomotive. Every time the locomotive passes the detecting site (near the base station ), the "box" is started by a certain signal and check the semaphore system and record the result which will be transmitted to the base station through wireless channel. The base station will collect the information from all the "boxes" and record it into the database.
In this system, several technical points are of interesting, (a) wireless channel distribution and organization (b) transmission encoding and decoding in wireless channel. (c) Optic-electronic transformation and isolation of detection result. (d) Loop programming method in accordance with the "Watchdog" hardware in microprocessor system. (e) Real-time Windows - based PC - Microprocessor interfaces.
I am the system designer and main hardware designer in this project.
4. Fiscal Information Management System
Beijing Forest Institute funded the software. I programmed it with Visual-Foxpro. The purpose of this development is to replace the manual recording and management of fiscal report. After the original fiscal data is inputted, the software will generate all kinds of fiscal report and table. This development is supervised by the accountants of the Institute, and accords with the existing fiscal rules of the Institute
5. Portable Wireless Data Transmission Terminal
A project sponsored by Railway Ministry of P.R.China. This system is used in the management of goods and materials in the railway station-yard. The operator record the information of the incoming out outgoing articles through the mini- keyboard on portable terminal, the terminal will send the information to the center station through wireless channel, the computer in the center station will store and deal with all these information. Also the operator can query the information stored in the computer through the portable terminal.
The technical points I took charge in were (a) High efficient power converter (battery to DC5, 12V). (b) Change the DOS resident data transmission channel program into windows – based programs, and frame design of the windows – based information management software. (c) High speed coding and decoding program using ASM51.
6. Remote Control Telecommunication System
An experimental project sponsored by Railway Ministry of P.R.China, in order to set up a new telecommunication system in mountainous areas based on a patent technique. The key idea is to transmit the signal to the weak field area through wire communication, and then send out to the air. The difficulty is that this system must be compatible with, and using the spare resources of the existing communication system.
This communication system consists of a center dispatching machine, a set of base station communicating with the dispatcher through wire, and the mobile station installed on the locomotive which communicates with the base station through the wireless channel, and set of remote controlling unit installed in the weak field area in order to receive, amplify and send out the wireless signal.
I took part in the system hardware design and implementation, and wrote the system control and communication software. Because of the harsh running environment, both the hardware and software design required system anti-deadlock and on-error restoration, which limits the programming flexibility. A new reset and watchdog circuit designed by me was adopted in the whole system and ran very well, and a new structural software design cooperated with this hardware was introduced by me, which improved the software programming flexibility.
This system ran successfully.
7. Efficiency of Taper Shaped LED – Optical Fiber Coupler
This work lead to my thesis for Master’s Degree. Taper Shaped Coupler a widely used coupler for LED, and the efficiency is function of the shape of the coupler and the LED, the relative position of the LED to coupler, thus the efficiency is very difficult to calculate because the 3-dimensional parameters and wave propagation phenomena. I a approximate this 3-Dimensional problem into 2-Dimension, which can be calculated by 2-Dimensional FFT algorithm. And I wrote the program with Matlab which has powerful FFT subroutines.
I did experiments with coupler and LED with sorts of parameters, and compare the experimental data with the calculated result, and they fit well.
8. New Method in MFD measurement,
FCM-1000 is a very important instrument in measuring optical fiber parameters, but the algorithm in calculating the MFD (Mode Field Diameter) is very simple and not accurate, because it doesn’t take into account the random errors in the mechanical measure. I designed a new nonlinear regression algorithm that concerns about the random errors, and rewrite the corresponding control and calculating program using HP-BASIC, which is the intrinsic language of this instrument.