Zhijie Xu

Welcome to my personal page!





### Who is Randy Pausch?
Randy Rausch is a Computer Science professor at Carnegie Mellon University and he is fighting with the pancreatic cancer.

### What was he known for?
He is well known for his "Last Lecture".

### 5 points that you liked in his talk.
1. Think time the same as money
2. Bad time management equals to stress.
3. Monitor my own time to figure out the time waste
4. Write thank you notes
5. Use Covey’s four quadrant to rank the events

Christos Kapoutsis – Theory of Computation

• What is a decision problem?
A problem will have only two possible outcomes, Yes or No.

• What does it mean for a decision problem to be decidable?
It can be solved by finite lines of algorithm.

• What does it mean for a decision problem to be efficiently decidable?
It means the decision problem can be solved by an efficient algorithm which will solve the problem with a specific time range, such as O (n2).

• What is the “P versus NP” question, intuitively?
It is an unsolved computer science problem. This problem indicates that some of the questions exist today will not be able to get an answer in polynomial time frame.

• If you resolve the P versus NP question, how much richer will you be?
This problem is one of the seven Millennium Prize Problems. If someone solves the problem, he or she will get US$1,000,000 provided by Clay Mathematics Institute.

Ryan Riley - Security

Research two major computer security incidents that have happened in Qatar.  For each, describe....
* What did attackers break into?
* How did the attackers break into it?
* Who was impacted?
* How was it investigated?
Incident 1
Iran and UAE hacked the Qatar News Agency website and its social media account. The attackers exploited the vulnerability in the website to aside the system and fetch the password. The impact is to all three countries. The Qatar government took legal action to against other two countries. The QNA also suffers by leaking password and be hacked to posted a news article which can potentially hurt the relationship between Qatar and the US. Qatar government seek help from the US FBI, and FBI provides a detailed report on this issue.

Incident 2
In 2012, the Shamoon virus was created by a group called “ cutting Sword of Justice” to attack the Qatari natural gas producer RasGas. The malware shut down the website and email servers, but did not hurt the main operation computers. The researcher found the Shaman has a destructive payload that deletes files on infected computers.

Mohammed Hammoud – Cloud Computing

1. What is cloud computing?
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction.

2. Is cloud computing a new technology per se? In other words, what are the unique technology features of cloud computing, if any?
Cloud computing has several unique features, such as support dynamic expansion of resources, support massive information processing and allocation base on demand.

3. What are the three major cloud service models?
Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Service (SaaS)

4. Name at least 3 real-world domains where the application of cloud computing was (or can be) very enabling and effective.
Online Video Game
Data Storage

5. What is the economic/business model of cloud computing?
The economic model of cloud computing can be seen as part of the sharing economy. The shared object of cloud computing is the right to use the server. Users will purchase cloud computing power and services. Then cloud computing companies can further improve the efficiency and portability of cloud computing through research and development.

Giselle Reis - Programming Languages

1. Why did we move from punch cards to programming languages? What does that tell you about the purpose of programming languages?
Since the punch cards are heavy, not easy to understand, difficult to erase, and expansive, a new technology is needed to control computer and input data. The purpose of programming language is to provide the instructions to computers with a lower cost and a clear interpretation.

2. There are hundreds of different programming languages out there. Why do you think we need so many?
The application fields of various programming languages are different, resulting in different requirements for compilation efficiency, code quality and execution speed.

3. What are some drawbacks of a programming language you use? How would you like it to be different? Think of specific examples.
Java Virtual Machine has the advantage of multiplatform. However, it is also the drawback of Java. Unlike swift and python, developing an application by using Java is not good, because JVM needs to be installed to run java programs.

4. If you were going to create a new programming language, how would you start? What do you need to define?
I need to design the features of the language; define the words, grammar and semantics of the language; implement the compiler or interpreter to translate the program into the low-level representation of the computer; generate the binary storage format of the computer program; and improve the runtime environment and standard library of the language.

Gianni Di Caro – Robotics and AI

1. How do you define AI?
Artificial Intelligences is the ability of a computer to do tasks that requires human’s intelligences and AI will normally simulate the humans’ actions.

2. Can you name at least three different sub-fields of AI?
Machine Learning
Natural Language Processing (NLP)

3. AI has been around since about 70 years so far. Why is it booming right now?
The calculation powers of computers are growing dramatically, which means the hardware can support for the most of data processing. The cost of building an AI is decreasing. Moreover, the algorithms are more efficient, the application of AI is more approachable.

4. Can you name at least three application sectors where robots are being largely employed? What are the reasons?
a. Heath care industry: Surgical robots can be used by doctors, since the robot will perform minimally invasive prostatectomies.
b. Manufacturing industry: For instance, Tesla has employed robots to install the components of the cars in Shanghai, because the robots will be more efficient and make less mistakes. Moreover, the company don’t have to train the employee to install car parts.

5. Can you identify three major challenges for a wheeled autonomous robot performing a 24h surveillance task in a large facility? (e.g., something like Mall of Qatar)
1. The robots may be damaged by people.
2. If a robot running for 24 hours, the heath of the hardware may in a very critical point
3. As the description said it is a large facility, one robot may not cover the whole area.
4. Moreover, the robot may hurt the customers if the algorithms have unnoticed bugs.

Kemal Oflazer - NLP

1. Name 3 applications on Natural Language Processing
Virtual Assistant: Siri
Auto-Correct: Grammarly
Machine Translation: Google Translate

2. Select three words in your language and for each word try to separate into its internal component. (e.g for English If I chose unbelievable I would break it as un-believ(e)-able)
北方有佳人 北方/有/佳人
人心 人/心
寸金难买寸光阴 寸金/难买/寸光阴

3. Select three sentences in your native language (but please write it in the closest latin transcription). Your sentences should be around 10 words. Translate these sentences to English) Indicate which words or small groups of words translate to which words or groups of words in English translation.
准(zhun)时(shi)准(zhun)点(dian)/睡(shui)觉(jiao)/很(hen)重(zhong)要(yao) on time/sleep/very important
英(yin)特(te)尔(er)/已(yi)/获(huo)得(de)/向(xiang)华(hua)为(wei)/供(gong)货(huo)许(xu)可(ke) Intel/has obtained/a license/to supply Huawei
习(xi)近(jin)平(pin)/主(zhu)张(zhang)/“人(ren)类(lei)命(min)运(yun)共(gong)同(tong)体(ti)” Xi Jinping/advocates/"a community with a shared future for mankind"

4. How many interpretations are there for the following English sentence "Time flies like an arrow" Write each interpretation descriptively?
Time moves in a way an arrow would.
Time flies as you would time an arrow.
Time flies in the same manner that an arrow would time them.