Units and Scientific Notation

1.Units The metric system of measurement is the standard in the world.The fundamentalunits include the second(s)for time,the meter(m)for length,and the kilogram(kg)for mass.     

Optimal parallel algorithm for shortest-paths problem on interval graphs

This paper presents an efficient parallel algorithm for the shortest-path problem in interval graph for computing shortest-paths in a weighted interval graph that runs in O(n) time with n intervals in a graph. A linear processor CRCW algorithm for determining the shortest-paths in an interval graphs is given.     

Biological activities of chamomile(Matricaria chamomile) flowers'''' extract against the survival and egg laying of the cattle fever tick(Acari Ixodidae)

In the present work, the potential of acaricidal activity of chamomile flowers' extract was studied against engorged Rhipicephalus annulatus tick under laboratory condition. For this purpose, the engorged females of Rhipicephalus annulatus were exposed to two-fold serial dilutions of chamomile flowers' extract (0.5%, 1.0%, 2.0%, 4.0% and 8.0%) using "dipping method" in vitro. The engorged ticks were immersed in different plant dilutions (five ticks for each dilution) for 1 min and they were imme-diately incubated in separate Petri dishes for each replicate at 26 °C and 80% relative humidity. Mortality rate for each treatment was recorded 5 d after incubation. The mortality rate caused by different dilutions of chamomile flowers' extract ranged from 6.67% to 26.7%, whereas no mortality was recorded for non-treated control group. The mass of produced eggs varied from 0.23 g (in 8.0% solution) to 0.58 g (in control), with no statistical differences between the treatments and control (P>0.05). Also the chamomile flowers' extract in highest concentration used (8.0%) caused 46.67% failure in egg laying in engorged females while no failure was observed for non-treated control group. Macroscopic observations indicated that in effective concentrations of plant (4.0% and 8.0%), patchy hemorrhagic swelling appeared on the skin of treated ticks. The results presented for the first time in this study imply that chamomile may be considered as a promising plant for biocontrol of cattle fever tick disease in the field condition.     

拯救海龟(英文)

Environmental groups in the United States are leading a campaign to save thousands of endangered (濒临灭绝的) sea turtles. They have asked Pope John Paul the Second to ban(禁令) turtle meat during the Christian religious observance (仪式,庆祝) known as Lent (四旬斋). Christians observe Lent in preparation for the holiday of Easter. Envi-ronmental groups say illegal turtle hunting is one of the major threats to endangered sea turtles in southern California and Mexico. It has been illegal to harvest and eat sea turtle meat in Mexico for more than ten years. However, demand for sea turtle meat is widespread in both Southern California and Mexico. Biologists believe that illegal hunting is one of the main reasons for the sharp drop in sea turtle populations during the past thirty years.     

含有…(in) doing sth的16个有用句式

1.be busy(in)doing sth忙于做某事Farmers were busy(in)getting in the crops.农民在忙着收庄稼。He was busy(in)packing,for he was leaving that night.他那时正忙着打点行李,因为那天晚上他就要走了。     

Oil

Almost everyone in the World uses oil(石油)in some way.Without oil,the world willstop,so men look for it everywhere.Oilmen drillfor oil in deserts(沙漠),in mountains and underthe sea.Quite often they find nothing,but thesearch(寻找)for oil always goes on.Oil is veryimportant because none of our machines can runwithout it.Big ships carry oil everywhere.Per-haps the oil in your bicycle or in your father’scar has come from somewhere far away.Perhaps     

110th Anniversary of Premier Zhou’s Birthday

Zhou Enlai or Chou En-lai(1898.3. 5——1976.1.8)was born in 1898 in Hwaian, Kiangsu Province,in a middle-class family; Chou attended Chinese,Western missionary and Japanese schools.In 1919 he was jailed briefly for involvement in student demonstrations.Upon his release,Chou went to Paris for study.He soon became a     

On-line real-time path planning of mobile robots in dynamic uncertain environment

INTRODUCTION Path planning of mobile robots is one of the key issues in robotics research on the problem of a robot finding a collision-free path from beginning to goal in the presence of obstacles. Depending on the envi- ronment surrounding the robot, it can be classified as follows: (1) Path planning for static obstacles in com- pletely known environment; (2) Path planning for static obstacles in un- known or partially known environment; (3) Path planning for dynamic obstacles in com- p…     

Two Stories

<正>Mrs. Weeks was reading a newspaper story to her class. The story said:Were you ever in a hospital when you were small? How did you feel? The doctors in Children’s Hospital were asking for money for children’s toys(玩具). Some children in the hospital must stay in bed for many weeks. Toys were needed to keep these sick(生病的)children happy and quiet. Money for them could be sent to the hospital.     

LDPC based differential unitary space-frequency coding for MIMO-OFDM systems

INTRODUCTION Unitary space-time modulation (USTM) (Hochwald and Marzetta, 2000) has been shown to be ideally suited for Rayleigh flat fading channels when there is no CSI. And for continuously changing fading channels, differential unitary space-time modulation (DUSTM) was proposed in Hochwald and Sweldens (2000). However, the performance of DUSTM de-grades considerably in frequency-selective fading channels often encountered in broadband wireless communications. Hence concatena…