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每逢节假日,在微信好友群发红包逐渐成为一种时尚,还能增进彼此的感情.2016年中秋节期间,小鲁在自己的微信校友群向在线的甲、乙、丙、丁四位校友随机发放红包,发放的规则为:每次发放1个,每个人抢到的概率相同.
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    Google, one of the world's outstanding tech companies, was attacked. It wasn't its search engine that was attacked or its advertising platform or even its social network, Google+. Instead, it was a building.

    Two web security experts hacked (侵入) into its Wharf 7 office in Sydney, Australia, through Google's building management system (BMS). One of them, Billy Rios, says, “My colleague and I have a lot of experience in web security, but it is not something that people couldn't learn. Once you understand how the system works, it is very simple.”

    They found the system on Shodan, a search engine that lists devices connected to the Internet, and then ran it through their own software to identify who owned the building. In the case of the Google hacking, the researchers had no immoral purpose and just informed Google about what they found.

    According to Mr. Rios, Who runs security company Whitescope, there are 50,000 buildings currently connected to the Internet, including research institutes, churches and hospitals, and 2,000 of those are online with no password protection. Martyn Thomas, a professor of IT at Gresham College in the UK, says, “It is beyond doubt that attempts to attack building management systems arc happening all the time.”

    Making a building smart generally means connecting the systems that control heating, Hating and security to the Internet and the wider corporate network. There was a strong reason for doing this, said Andrew Kelly, principal security consultant at defence company Qinetiq.

    “Energy savings are the biggest factor in connecting building management systems to the corporate network,” he says. “It gives those who run the building better control and offers between 20% to 50% in energy savings,” he adds.

    But it also makes them less secure. And if any of these feels like a Hollywood film, think again.

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史学大师许倬云

    许倬云1928年出生于无锡大族,出生时手脚弯曲,一直不能动。直到七岁才能坐在椅子上,长大后肌肉不发达,终生借助双拐行走。小时候,许倬云没法上学,只能在家自修。时任厦门海关监督的许风藻,人文学术素养很高,经常给儿子随机指点:给他讲数学、讲历史、讲语文,教他有关战争史、政治学与外交学等。许倬云起初爱看武侠小说,许风藻说:“你别老看武侠小说,好好看看《史记》。”于是许倬云从十来岁开始读《史记》《左传》,读了许多古书。

    1934年,许倬云随父亲移居沙市荆关监督公署。抗战开始后。因沙市地处要冲,逃难的人经此转往四川,川军也经此开赴前线。在沙市家门口的下马石旁,眼看见一队队川军开往台儿庄,有许多士兵还是小孩子,只有七八岁的许倬云,因毋亲一句话,“这些人可能再也回不来了”,一夜之间长大。当时许倬云父亲负责供应军粮民食,许家人也枕经常随着军队转移,或者随着难民逃难。很多时候,许倬云被摆在一个土墩、石磨、板凳上,作为一个旁观者。满目所见,尽是战火纷飞,流离失所,生离死别,知道了什么叫饥俄,什么叫恐俱。也因此。许倬云看到了中国最深入内地的农村,看见最没有被外面触及的原始原貌。七十年后回顾起这段往事,许倬云还是忍不住伤心流泪。

    1949年,许倬云随家人迁台,考入台大外文系。因为中文和历史考得好。在傅斯年的建议下转入历史系一直读到硕士毕业。当年的台大大师云集,使学生有更多机会去接触不间的思想、不同的学派,也可以选择不同的课题。再加上当时上课常常是一个人一班,等于几个名师一起训练许倬云。这在以后是不可想象的学习条件。许倬云终生感激这些不同风格的老师,每个人都给他一些东西,他没有走任何老师的路,而是自己走出一条路,这条路受每位老师很大的影响。

    1957年,时任“中研院”考古所助理研究负的许倬云,获得纽约华侨徐铭信提供的1500美元奖学金,赴芝加哥大学攻读历史学博士。在芝大的五年,许倬云在学术上突飞猛进,除了历史以外,他还接受了社会学、宗教学以及计量统计学方面的训练,也熏染了芝大“眼光宏阔”的学风、大问题意识,这些影响了他一生的治学方向。不过,何炳棣在回忆录中,对芝大这种学风颇有微词﹣﹣只做“世界第一流的学问”。2010年“中研院”为许先生庆寿,院士杜正胜如是评价:“许先生最大的影响不在于上古史,而在于所引入的那种关注杜会经济领域的研究视角。”

    在两岸三地,许伴云影响更大的可能是大众史学的写作。近二十年来,他陆续山版了《万古江河》《从历史看管理》以及新近出版的“许倬云说历史”系列四册等几十种,有的是精心撰著而成,有的则是根据在企业、高校讲座的课件整理而成,都有着一以贯之的内在理念一﹣关注与当下、与中国相关的大问题。或许,这种文字背后的问题意识和情怀,也是许先生的书收到白领、商人、学生等阶层喜爱的原因。

(摘编自云君《许倬云:旁观者的深思》、冯俊文《许倬云:一位历史学家的奥德赛》等)