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CTF是什么?

CTF(Capture The Flag,夺旗赛)是一种计算机安全竞赛,在网络安全领域中指的是网络安全技术人员之间进行技术竞技的一种比赛形式。

CTF模式

  1. 解题模式,jeopardy\
  2. 攻防模式,attack-defense\
  3. 静态攻防模式,attack-defense-pro\

CTF内容

由于CTF内容广,所以选手们往往选取1-3个喜欢的方向钻研,包括\ 1. 逆向工程(Reverse Engineering) 研究二进制程序,分析其行为,找到漏洞并理解其内部结构。常用工具:IDA Pro、Ghidra、Radare2、OllyDbg。 学习要点:程序结构、汇编语言、调试技巧、动态分析。

  1. 漏洞利用(PWN) 通过利用程序中的漏洞,突破程序或系统的限制,获取控制权。通常涉及缓冲区溢出、堆栈溢出等。 学习要点:内存管理、缓冲区溢出、堆栈保护、GDB调试、ROP(Return-Oriented Programming)。

  2. 密码学(Crypto) 解决与加密算法相关的题目,通常涉及对称加密、非对称加密、哈希、数字签名等。 学习要点:常见加密算法(AES、RSA、DES等)、哈希函数(MD5、SHA等)、密码攻击(暴力破解、侧信道攻击等)。

  3. Web安全(Web) 研究和利用Web应用中的漏洞,如SQL注入、跨站脚本(XSS)、文件上传漏洞、命令注入等。 学习要点:HTTP协议、Web应用架构、常见漏洞(XSS、CSRF、SQL注入、命令注入等)、工具使用(Burp Suite、OWASP ZAP)。

  4. 取证(Forensics) 通过分析数据、文件、日志等信息来还原事件,找到隐藏的秘密或证据。 学习要点:磁盘取证、内存取证、文件分析、数据恢复。

  5. 杂项(Misc) 其他综合性较强的题目,可能涉及一些不太常见但有趣的技能,如编码解码、异或加密、隐藏数据等。 学习要点:编码与解码(Base64、URL编码、异或加密等)、逻辑推理、数字信号处理等。

MISC

OSINT(Open-Source Intelligence)

OSINT(Open-Source Intelligence)是指从公开来源收集到的信息。

Unit 3 Science and Methods

口试内容参考

  1. But they are very proud of their calling and prefer to talk to other scientists rather than anybody else, especially poets, who tend to makethem feel uncomfortable, to put them down.\ The authors thinks that scientists are not willing to talk to poets because poets usually make them feel uncomfortable.What do you think of this statement? Illustrate your opinion with examples.

    While the statement may hold true in specific instances or contexts, it's also a generalized perspective that doesn't for the diversity within both groups.

    scientists preference for precision, logic and objectivity vs. poets' embrace of ambiguity and subjective interpretations This difference in communication styles might make conversations between the two groups challenging or even uncomfortable. Scientists may feel that the fluid and interpretative language of poets lacks the clarity they value, while poets may view scientific language as overly rigid or uninspired. example: A physicist explaining the mechanics of black holes may focus on equations and observations, while a poet might describe them as "cosmic portals to nothingness." Both are valid perspectives, but the poetic approach might feel abstract or frustrating to a scientist accustomed to measurable facts.

    While there may be moments of discomfort in interactions between scientists and poets due to differences in language, focus, and worldview, this discomfort often stems from misunderstandings or biases rather than irreconcilable differences. In reality, scientists and poets have much to offer one another. When they engage in open dialogue, they can inspire each other and deepen both the understanding and appreciation of the world.

    Many scientists appreciate poetry and find value in its perspective. Similarly, poets often draw inspiration from scientific discoveries. The discomfort described in the statement is far from universal.

  2. ...the Pythagorean view that the world... is essentially mathematical and thus intelligible because the human mind is essentially mathematical, too.\ What do you think of the Pythahorean view? Give your explantions.

    The Pythagorean view that the world is fundamentally mathematical provides a powerful framework for understanding the universe. It explains why mathematics is so effective in describing natural phenomena and why the human mind is so adept at uncovering these mathematical truths. While debates about whether mathematics is discovered or invented persist, the undeniable success of mathematics in science and its universal applicability suggest that the Pythagorean view holds significant merit.

  3. Can you share your opinions on scientific education, especially on observing those phenomenon of daily life?\

    Scientific education, especially when it emphasizes observing and understanding phenomena in daily life, is one of the most effective ways to cultivate curiosity, critical thinking, and problem-solving skills.

    Observing daily life phenomena is one of the best ways to make science accessible and engaging. It connects abstract concepts to tangible experiences, fosters critical thinking, and equips students with problem-solving skills. By incorporating curiosity-driven observation into scientific education, we can nurture a deeper appreciation for the natural world and empower students to approach life with curiosity and creativity.

Unit 5 Humans and Nature

口试内容参考

  1. Today, many animals are being endangered due to deforestation, pollution, habit destruction, huntings, and many other factors caused by us human interferences. The biodiversity of life on Earth is now delining faster than at any time in human history.

  2. Why do we need to protect the environment?\

    In my opinion all those reasons are human-oriented, protecting the environment and the wild endangered animals is

Unit 6 Chinese Tradition and Culture

口试内容参考

1,The culture of Chinese people closely adheres to the concept of Taoism and Confucianism. Both of them promote the inner pease of individuals and harmony with nature by ``following the Way'', which denotes something that is both the source and the force behind everything that exists.

  1. The authors believe that one of the drawbacks of the Chinese writing system is rote memorization. What's your opinion? Do you agree that it has a limiting influence in Chinese education? Why or why not? Use examples to illustrate your opinion.

Rote memorization, especially in relation to Chinese characters, does indeed present challenges in terms of cognitive load and the development of creative, critical thinking skills. However, it is also deeply embedded in the cultural and historical context of Chinese education.

In recent years, China’s education system has made efforts to balance rote memorization with creativity and critical thinking. There is a growing emphasis on active learning and problem-solving. New teaching methods, such as project-based learning, are being introduced in schools, particularly in urban areas.

In summary, while rote memorization has its drawbacks—particularly in terms of stifling creativity and critical thinking—it also has a historical and cultural significance that cannot be overlooked. The challenge for Chinese education today is finding a balance between maintaining traditional values and adapting to the needs of the modern world, where skills like creativity, innovation, and problem-solving are crucial.

In my opinion, rote memorization should not be seen as inherently limiting but rather as one component of a well-rounded education system. If it is integrated with critical thinking, creativity, and hands-on learning experiences, it can become a powerful tool for deep learning. Moving forward, the Chinese education system may benefit from continuing to evolve, incorporating more interactive, problem-based, and inquiry-driven approaches that complement traditional memorization techniques.

  1. The authors seem to believe Chinese education has put a premium on writing instead of speaking. Do you agree? Why or why not? And if you think in tradtional Chinese society writing did outweigh speaking in education, do you think that still is the case today? If not, what have prompted the change?

I agree that traditionally, Chinese education has put a stronger emphasis on writing over speaking, and this has had significant implications for how language, communication, and learning are approached in Chinese society. However, I also believe that significant changes have taken place in recent years, and the focus is gradually shifting toward balancing speaking and writing skills, especially in modern education.

In traditional Chinese society, writing was considered the most prestigious form of communication, particularly due to the historical importance of scholars and scholars’ exams (such as the imperial examinations, or 科举). These exams were based primarily on the ability to write essays, interpret classical texts, and demonstrate scholarly knowledge, often with little regard for spoken communication.

Success in the exams could lead to prestigious government positions, so writing ability was not only an academic skill but a key to social and economic advancement.

Even today, Chinese education places a high value on writing, particularly in areas such as Chinese literature and history. School exams, especially the Gaokao (the national college entrance exam), still involve a significant amount of writing. Students are tested on their ability to compose essays, analyze texts, and demonstrate their understanding of classical literature.

Several factors have prompted this shift from writing to a more balanced focus on speaking:

Globalization: As China has become a global power, fluency in speaking—particularly in English—has become more important. International business, diplomacy, and cultural exchange require strong oral communication skills. Educational Reforms: The Chinese government and educational institutions have recognized that a modern education system needs to prepare students for a diverse range of communication scenarios, including interpersonal conversations, presentations, and collaborative work, all of which require speaking skills. Technology and Innovation: The rise of digital technology and social media has democratized speaking opportunities. As these platforms encourage interaction and discussion, students and young people are increasingly exposed to the value of speaking in real-world contexts.

我为什么要做这个个人博客

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更新日历:

2024.11.10 今日积了三十道不定积分,好一个积积复积积。

2024.11.11 积不动了,二十道……

2024.11.12 十道(悲)

2024.11.13 十二道

微分

微分的几个重要定理

微分中值定理

定义1.2.1(极值点)

在区间上有定义,若存在,使得 在去心邻域恒成立, 则称的一个极大值点.称为对应的极大值. 同样的,我们可以定义极小值点,若在有定义的范围内,一个点的去心邻域内的函数值都大于等于该点的函数值, 则称该点为的一个极小值点,对应的值为极小值.

关于极值点的概念,有几个需要强调的地方:

  1. 极值点是局部的,而不是全局的,一个函数可以存在多个极值点.
  2. 一个函数的极小值点可能比它的一个极大值点大.
  3. 极值点的存在与函数的连续性,可微性无关.

定理1.2.1(Fermat引理)的一个极值点,且处可导,则.

[证明]

不妨设的一个极大值点,由极值点的定义可得:, , , 因为处可导,故.

, , 故.
同理可证为极小值点的情况.

积分

不定积分

有理分式的不定积分

其中 分别为次多项式与次多项式,且 。 设

(待补充)

切比雪夫定理

$ 2. ,令N为P的分母,a+bxn=tN \ 3. +P ,令N为P的分母,axn+b=tN $ (待补充纯参数推导)

例: 使 例:

例:

使

例:

使

例: 使

例: 使

例: 例: 推荐书目:《无穷分析引论》欧拉

从明天就要讲的pre开始

明天就要讲小组pre了,但因为事太多 摆烂 上个周末花了一小时把我负责的那部分稿子写出来后就再没有去碰它,不过还好稿子不长,而且其中大半都是Chatgpt写的,所以还有一定学习价值,今天就一边背一边学一些表达吧。

本次学习方法为:解析造句记忆

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