A recent U.N reports states that, to overcome the water and sanitation calamity is one of the greatest challenges mankind have to tackle in the early 21st century. (United Nations Development Programme, p. 1) A large percentage of deaths in the world are due to poor access to clean water, which results in poor health quality. Seventy percent of the world, covered with water, makes it adequate for the world's population; nevertheless, it is not always located at regions where it is needed the most. In addition to the severity of this problem, political and economic barrier, waste discharge into clean water sources also affects the availability of clean water. Seawater consists of large percentage of salts, which makes it not usable for agriculture, industrial, ecological processes and the like. One way to tackle this problem is by extracting salt from seawater also known as desalination; reverse osmosis technique uses membrane to separate salt from water, to provide clean water for domestic needs. However, desalination plants are expensive to build and lots of energy is required for it to operate This, is impossible in poor countries where water supply problem are most serious. A more practical technology, which uses less cost and energy, is called nano-osmosis where salts are filtered out by nanotubes (tiny tubes of carbon), effectively and efficiently. Besides that, recycling of wastewater and sewage treatment is being exercised to provide water for non-personal use but to do that, we need effective purification method and rigorous buffer to unsure the safety of recycled water. Other approach involves strategies for reducing water use such as drip technology for agricultural purposes and small-decentralized distillation units for rural and low-income areas where water problems are acute. In addition, new technologies are being studied where contaminant can be extracted from water effortlessly. In future, with the evolution of engineering, clean and cheap water may be available for all without any impediment!
Source: National Academy of Engineering. Grand Challenges for Engineering. http://www.engineeringchallenges.org/cms/8996/9079.aspx
4 comments:
Hi Calvin!I think you have successfully input every single piece of important information found in the original article. Informations are organised well and it's easy to understand. I think it's good.
Hi Calvin, your summary is clear and very convincing as it consists of most of the important notes in the article. Connecters are used frequently, making the summary flows smoothly. Personally, I think the part of water supply should also be included, as there are also some challenges mentioned, even though adding it may cause the summary to be much longer. For the 2nd sentence, instead of ‘A large percentage’ I suggest you could consider using ‘A large number’. Although it is mentioned there an estimated of 5000 children die each day, it seems a lot to us, but compared to the total death of children per day it’s actually not a major percentage. Besides, I think the sentence ‘Seventy percent of the world is made of water, which makes it adequate for the world's population’ sounds a bit strange, because I think I would write in this way: ‘seventy percent of the world is covered with water, and this seems to be adequate for the world’s population’. The sentence is not wrong, I get what you mean, but I just think of, the water is abundant doesn’t mean it’s adequate, so I guess maybe a more objective word should be used here. Anyhow that’s just my view, comments are welcomed.^^ One more thing is, I think using the word ‘and’ twice in a sentence is quite common but it’s strange to use the word ‘where’ twice in the sentence. Perhaps you can try changing the sentence structure by using commas. Finally, sorry for such long comment, I hope you don’t mind @@
thank you wern fei. i have made some amendments from the pointers you gave me! thanks a bunch! :) and please do not be afraid to comment on my essays. i need honest comments so that i can improve :) thanks again!
hello Calvin!
I have just realized that there are only you make citation in the summary. I even have forgot about that.Generally, your entry is so clear that readers can get the whole idea at once. On the other hand,I think you should pay more attention to the usage of punctuation because I don't know why there is "!" at the end of your summary. In addition, maybe your title should be changed to make it easier for others to follow since it is e-profolio 3 now. Nice weekend!
Post a Comment