日批在线视频_内射毛片内射国产夫妻_亚洲三级小视频_在线观看亚洲大片短视频_女性向h片资源在线观看_亚洲最大网

US EUROPE AFRICA ASIA 中文
China / Across America

Analytical tool may improve prediction of flooding

By Paul Welitzkin in New York (China Daily USA) Updated: 2017-05-23 10:33

An American professor and a research assistant who is a native of China have developed an analytical tool that will enable a more reliable prediction of when rivers like the Yellow in the mainland will flood.

Jeff Nittrouer, an assistant professor of geology at Rice University in Houston and Hongbo Ma, a post-doctoral research associate at Rice, who hails from Hegang in Heilongjiang province, have created a new physics-based formulation that can calculate sediment transport in major waterways like the Yellow River, or Huanghe, the second-longest in China after the Yangtze River.

The Yellow River is considered by many to be the cradle of Chinese civilization. The headwaters begin in the Kunlun Mountains in northwestern Qinghai province. The river runs through nine provinces before emptying into the Bohai Sea.

"The river has cultural significance because the first feudal empire, the Xia Dynasty, was formed based on the geography of the river about 4,000 years ago," Ma said in an interview.

In addition to its cultural and political heritage, the Yellow River has also become an economic development mechanism. Sediment from the river winds up on both sides of its banks to create flood plains and deltas that become fertile soil for agricultural products. Because the river also serves as a major transportation route, businesses and towns and cities are also located near the waterway.

Analytical tool may improve prediction of flooding

When the river floods, it can cause major devastation. "Yellow River flooding has resulted in the deaths of millions in the last 2,000 years and a lot of property damage," said Ma.

A similar delta exists in New Orleans where the Mississippi River empties into the Gulf of Mexico, said Nittrouer in an interview, who also said that most deltas in the world are threatened by rising sea levels.

He said the Yellow has a high sediment load and it tends to become a clogging agent that causes the river to overflow its banks.

"We are trying to understand the mechanics of water and sediment movement in the river," Nittrouer said.

To accomplish that task, Nittrouer and Ma began researching the Yellow about two and a half years ago. They utilized computers, sediment samplings and 3-D sonar equipment to map the bottom of the river. Using all of that, the pair developed a physics-based formula capable of predicting the volume of sediment transported in a certain time period.

Ma said accurately determining the amount of sediment in the Yellow may allow officials to "get out an early warning that could save lives and property".

"We found that the river has an abundance of sand and the water flow led to the buildup of dunes on the bottom much like the wind does in the desert," said Nittrouer.

paulwelitzkin@chinadailyusa.com

Highlights
Hot Topics

...
主站蜘蛛池模板: 欧美日韩三区 | 亚洲天堂网在线观看 | 欧美视频中文字幕 | 手机看片1024日韩 | 欧美激情精品 | 国产无套免费网站69 | 成人在线毛片 | 欧美激情一区二区三区四区 | 欧美日韩一区二区在线观看 | 久久免费视频99 | 九七超碰在线 | 欧美xxxx日本和非洲 | 午夜精品久久久久久久 | 九九热这里都是精品 | 超碰在线99 | 少妇又色又爽又黄的视频 | 最新日本中文字幕 | 成人国产精品视频 | 亚洲无限看| 日本欧美一区二区 | 欧美影音 | 操天天操 | 日韩一区二区三区在线视频 | 国产高清一级片 | 国产高潮久久久 | 国产精品视频免费在线观看 | 国产一二三级 | 久久尹人| 国产精品理论在线观看 | 国产精品亚洲lv粉色 | 一区二区三区国产精品 | 激情六月天 | 在线免费观看一区 | yellow网站在线观看 | 国产精品激情 | 男人av网 | 久色成人网 | 一区二区三区视频 | 欧美成人精品一区二区三区在线看 | 四虎影院最新网址 | 久久成年视频 |