| 5 | 1/1 | 返回列表 |
| 查看: 13309 | 回復(fù): 3 | ||||
| 當(dāng)前只顯示滿足指定條件的回帖,點(diǎn)擊這里查看本話題的所有回帖 | ||||
lowlyshowy新蟲 (初入文壇)
|
[交流]
臭氧 8小時均值 怎么計(jì)算? 已有1人參與
|
|||
| 有一天24小時的臭氧濃度的時均值,如何計(jì)算當(dāng)日的臭氧 8小時濃度均值?謝謝! |
好東東 |
|
8小時濃度均值即連續(xù)8個小時濃度的平均值。對于臭氧,應(yīng)取連續(xù)8個小時平均值的最大值. 例如N1=avg{c1,c2,c3,,,,c8} N2=avg{c2,c2,c3,,,,c9} N3=avg{c3,c2,c3,,,,c10} 依次推出,N17=avg{c17,c2,c3,,,,c24} 臭氧日8小時最大值=max{N1,N2,N3,,,,,N17}. 這里有一點(diǎn)需要注意:上面到N17就結(jié)束了,但是否繼續(xù)循環(huán)下去,即一直到N24=avg{c24, c1‘,c2',c3',,,,,c7},才算一整天,即今天與明天是否有交疊的情況,這個得查美國的做法。 [ Last edited by byfgogo on 2013-1-31 at 22:23 ] |
新蟲 (初入文壇)
|
EPA上的Q&A里面有解釋 Q: How do I compute the daily maximum 8-hour average ozone concentration? The new Aerometric Information Retrieval System (AIRS) will do this computation for you. First, running 8-hour averages are computed from the hourly ozone concentration data for each hour of the year and the result is stored in the first, or start, hour of the 8-hour period. In the event that only 6 (or 7) hourly averages are available, the 8-hour average is computed using 6 (or 7) as the divisor. Generally, if fewer than 6 hours of ozone concentration data are available, then the 8-hour daily maximum concentration for the day is assigned the value of ‘ missing.' However, just because we are missing more than 2 hours of monitoring data, we do not want to ignore 8-hour concentrations that clearly exceed the level of the standard. When more than 2 hours of monitoring data are missing, we compute the 8-hour average concentration by substituting one-half the minimum detectable limit for the missing hourly concentrations and using 8 as the divisor. In this case, if the computed 8-hour average concentration is greater than 0.08 ppm, it is retained, otherwise the 8-hour concentration for this 8-hour period is assigned the value of ‘missing.' In all cases, the computed 8-hour average ozone concentration is reported in parts per million (ppm) to three decimal places (the insignificant digits to the right of the third decimal place are truncated). |
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 材料專碩322分 +9 | 哈哈哈吼吼吼哈 2026-04-02 | 9/450 |
|
|---|---|---|---|---|
|
[考研] 求調(diào)劑求調(diào)劑 +6 | 121. 2026-04-02 | 6/300 |
|
|
[考研] 一志愿北京科技大學(xué)085601材料工程英一數(shù)二初試總分335求調(diào)劑 +9 | 雙馬尾痞老板2 2026-04-01 | 9/450 |
|
|
[考研] 311求調(diào)劑 +16 | zchqwer 2026-04-01 | 18/900 |
|
|
[考研] 070305高分子化學(xué)與物理 304分求調(diào)劑 +14 | c297914 2026-03-28 | 14/700 |
|
|
[考研] 一志愿北交大材料工程,總分358 +4 | cs0106 2026-04-01 | 4/200 |
|
|
[考研] 材料調(diào)劑 +14 | 一樣YWY 2026-04-01 | 14/700 |
|
|
[考研] 材料與化工(0856)304求B區(qū)調(diào)劑 +8 | 邱gl 2026-03-30 | 16/800 |
|
|
[考研] 材料專碩306英一數(shù)二 +7 | z1z2z3879 2026-03-31 | 7/350 |
|
|
[考研] 283求調(diào)劑 +9 | A child 2026-03-28 | 9/450 |
|
|
[考研] 一志愿北交材料工程總分358 +5 | cs0106 2026-04-01 | 7/350 |
|
|
[考研] 322求調(diào)劑 +8 | 三水sss 2026-04-01 | 8/400 |
|
|
[考研] 288資源與環(huán)境專碩求調(diào)劑,不限專業(yè),有學(xué)上就行 +25 | lllllos 2026-03-30 | 26/1300 |
|
|
[考研] 考研調(diào)劑 +9 | 小蠟新筆 2026-03-29 | 10/500 |
|
|
[考研] 340求調(diào)劑 +4 | 希望如此i 2026-03-31 | 4/200 |
|
|
[考研] 一志愿大連理工大學(xué),機(jī)械工程學(xué)碩,341 +3 | 西瓜田的守望者 2026-03-30 | 3/150 |
|
|
[考研] 085701環(huán)境工程求調(diào)劑 +11 | 多久上課 2026-03-27 | 12/600 |
|
|
[考研] 322求調(diào)劑 +10 | 宋明欣 2026-03-27 | 10/500 |
|
|
[考研] 283求調(diào)劑(080500) +14 | A child 2026-03-27 | 14/700 |
|
|
[考研] 296求調(diào)劑 +10 | 彼岸t 2026-03-29 | 10/500 |
|