若$0<\alpha <\frac{\mathrm{\pi }}{2},-\frac{\mathrm{\pi }}{2}<\beta <0,\cos \left(\frac{\mathrm{\pi }}{4}+\alpha \right)=\frac{1}{3},\cos \left(\frac{\mathrm{\pi }}{4}-\frac{\beta }{2}\right)=\frac{\sqrt{3}}{3}$，，则$\cos \left(\alpha +\frac{\beta }{2}\right)$=____ 

【环境保护】

    纽芬兰渔场曾是世界四大渔场之一，有“踩着鳕鱼群的脊背就可上岸”的传说。自20世纪五六十年代开始，大型机械化拖网渔船成群结队地驶入了纽芬兰湾。这些渔轮夜以继日地捕捞，庞大的捕鱼网兜掠过海底，除了鱼群在劫难逃，连海底生态也被破坏殆尽。面对鳕鱼资源的枯竭，加拿大政府被迫于1992年宣布彻底关闭纽芬兰及圣劳伦斯湾沿海渔场。如今关闭已二十多年了，鱼群仍不见踪影。

    就在纽芬兰出现危机的时候，隔着大西洋相对的国家——挪威的鳕鱼也开始告急。鳕鱼捕捞是挪威北部的经济命脉，幸运的是，经过3年的痛苦等待，挪威的渔民们终于欣喜地看到了大鳕鱼群的回归。

    依据材料及所学知识推测挪威政府为了保护鳕鱼资源采取的措施。

    Running away is a serious problem. There are lots of runaway and homeless kids living in the streets around the world.

①孩子们为什么想离家出走？

    Some kids run away because they're afraid to tell their parents the bad things that they did at school or in society.

②Some kids run away because there is violence(暴力）in the family.

    Some kids run away because their parents divorce(离婚）or marry again.

    Some kids run away because they have problems at school.

    What will you do if your friend wants to run away from home?

    If your friend is thinking about running away, tell him or her that it is difficult to survive(幸存）in the streets. Try to help your friend feel less alone.

    ③Whatever the problem is, there are other ways to solve it. Maybe you can't think of the ways right now, but an adult(成年人）will know how to help you. You should tell an adult that your friend plans to run away as soon as possible. Being a real friend doesn't mean keeping a secret that may hurt someone. And running away isn't a solution(解决方法）for either of you.64.It only makes more problems and danger.