this, we can know that axial impeller is not suitable. Also, because of wide width of tank, it has poor mixing.
Second, there is a problem with chemicals. PAC is injected with Cl2, so activation of Cl2 must be restricted.
Also, using alum may cause settling.
Alum lowered pH in localized area. To overcome this problem, we need more alkali materials and it means lots of cost.
1. Introduction
1) reason of choice MSA
Health insurance is an insurance that pay medical cost.
We don't know when we sick, what we catch disease or how we sick.
And when medical cost is big, it is a burden on people.
So insurance exist as way to guarantee living healthy.
However, now Korean health insurance face with a crisis.
Our health insurance premium is low, so expenditure of medical
This idea can be applied to logistics as well. In the past, logistic cost has been defined in purely monetary terms. However, as not only in the EU but also in the USA and other countries became more and more aware of environmental problems ,for instance because of climate change, air pollution, noise and accidents, environmental considerations has been taken in logistics kfield. This is how Gree
Ⅰ. 서론
초등학교 영어교육에서 우위성의 문제는 보다 구체적으로 “수업 과정에서 교사가 학습자들에게 바라는 것이 무엇인가”를 밝히는 것과 직결된다. 어느 교과 수업에서와 마찬가지로 교사는 무엇보다도 학습자들이 수업에 적극적으로 참여하기를 바랄 것이다. 또한 교사는 학습 과정에서
3. Experiment & Procedure
3-1 Reagent
- Water, 수돗물(15℃)
3-2 Apparatus
- single media deep bed filter column
- manometer
- mass cylinder
- thermometer
- stopwatch
3-3 Procedure
1) 실험에 사용할 여재(모래)를 준비한다.(세척 및 이물질 분리)
2) 모래를 건조시킨 후, 체 거름을 이용하여 입자 크기를 잰다.
3) 공극률(P