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Leadership Principle (BFS) - Coggle Diagram

- - - - What are their needs?
        
        How to solve their problems?
  - - - I make the decision.
        
        I’m the owner.
- - - - Answer (Earn Trust)
        
        After I finished my summer internship project. I still make some update and bug fixing and push them for pull request. One time I accidentally updated all the dependencies, cause at that time I was not paying too much attention to how they affect the usage of the main project, which is not wise. I also only tested one part of the project.
        This caused a big issue in the pull request, caused the Travis CI to report a bunch of code. I was really nervous and wen to ask for help from the main contributor. Then he told me how to fix them and push again to fix the problems.
        From that I learned that testing is necessary before pushing anything, and ask the experienced people before make big changes.
      - Lessons I Learned
        
        Bias on Action: a little bit too much, but good after control (ask and listen);
        Earn trust: ask and communicate more, and test more often;
        Curious and Learn: start to curious about the automated testing process, cause they are super useful in finding mistakes, and prevented me from making more issues to the whole project (always apply those principles on my development procedure)
        Dive deep: take some course, and applied on my project (what tools? examples about usage and principles?)
    - - Tell me about a time when you received negative feedback from manager, and how you responded.
        
        Answer
        
        How did you built your wallet?
        
        I was working with a profession on some blockchain research projects. After a month, he complained that I didn’t make any progress in my project.
        I was confused at that time, and then I realized that in one of his presentation in a conference, he used an API I built for this project. I was surprised that I didn’t receive a credit.
        Then I realized that the problem is that I only communicate with the PhD student he assigned to me, and didn’t do a good job in communicate with him face-to-face.
        So I told him the situation of me, and decide to start another project from scratch. With only 1/3 of the time, I finished the project on time with high quality. And regain trust from the profession.
        My problem: I should communicate more with professor and update more often.
        
        My Lessons
        
        I still appreciate the help from the PhD student, but I decide to not let the old project to be an issue anymore, so I decide to start a new project from scratch, and focus on that (have backbone, and safe not);
        I get advices from the professor this time, and actively communicate with him for my thoughts in the project. Then I decided to build an electric wallet with the cryptography knowledge and learned from that semester, cause I also want to learn more by challenge myself to learn something from scratch, such as Go programming language. (dive deep + curious and learn);
        By the end of the semester, I earn trust back from the professor by exceeding the expectation of the project (Earn trust + Insist of the highest standard)
        
        Pitfall
        
        Don't say I don't thing his is right or that's not true!, just say I want to understand why.
    - - Tell me about a time when you were working on a project on a time constrain.
        
        Tell me about a time when you flet you wouldn’t be able to get something done or had to take a pivot at the last minute.
        
        Answer
        
        The E-commerce project I got is due in dead week. But there are still some corner cases need to be fixed, esp. the image ratio issue.
        So I did my best to using the CSS script to make the image to stay in the right ratio. Then I talked with the client, and told him the situation. And since I don’t want to settle in low-standard, so I told him that I will make sure theses issues will be fully resolved after I finished my final. And he accepted my request.
        After that I build a tool to convert the image to the right ratio and perfectly solved the problem for my customer without wasting budget to getting help in the future.
    - - Answer (Are Right, A Lot)
        
        I joined a start up weekend before I graduated from UW in college. The business model of our team is to using the social media data to predict the cryptocurrency market.
        At that time I toke a class about machine learning with professor Emily Fox, and she is a really good teacher. So I learned both the theory and implementation of many algorithms related to natural language processing. Thus I suggested to build a sentimental analysis tool based on the data we have.
        At that time I suggested to use Logistic Regression to classify Buy/Sell signals, and the threshold can be adjusted with cross validation.
        But the other two teammates believe that SVM is something they are familiar and want to give it a try. I value their ideas, so gave us one day to try, so that even if something went wrong, I can still help the team to implement a LR solution. I believe that it’s always better to make some decision first, and then after we gain more new information, then we can pivot if necessary.
        The result is that after we work for a long time on Saturday, the result was still only around 60% accuracy until the Sunday morning. We will need to present result in the afternoon, so I finally decide to propose again, and they accepted my idea to try.
        We worked together, I fully in charge of the training model and constructing Sentimental analysis model based on the S3 product review dataset. Then I used the reddit comments from my teammates from May 2017 to May 2018 to do CV. The result is eventually higher than 80%. And another teammate finished the front end visualization by plotting the price history, and the sentimental result output from my algorithm. This made us to won the first place in that year amount 50 other teams.
        
        How LR works, and how it can be applied to Sentimental Analysis.
        
        LR
        
        The LR is basically a function that given some inputs, you predict the probability of the output to be 1 or 0. In here, 1 is buy, and 0 is sell. They way we can build the model or finding the parameters for the mathematical functions, is using gradient descent to minimize the cost function with the given data set.
        The logistic function looks like: e^x / (e^x + 1)
        And the model is: `1 / (1 + e^-(b_0 + b_1 * x))
        
        Why not SVM
        
        Because my intuition at that time is that the sentimental data between buy and sell classes are highly mixed in sentimental analysis or the data are not very clearly separate. That means they are not necessarily linearly separable.
        Using SVM to accomplish non-linear separation requires change of kernel and that requires some mathematical manipulations. We only had 1 day to finish the whole project, so I don’t want to spend too much time on picking a hard problem when there is a choice that can give good general result fast.
        Also LR can be easily optimized with gradient decent to the cost function, and régularisation (lower change of overfitting), and can easily tuning the threshold in CV. The concept is easier to understand. That’s why I pick this one then the other.
        
        Also using probability is more intuitive and straight forward to let investor and users to understand the decision making than bending the graph to a higher dimension to increase the accuracy.
        
        Sentimental analysis
        
        Data Cleaning
        
        Remove the NaN fields (rows)
        
        Remove the rating for 3, and then let 1-2 to be negative (sell), and 4-5 to be positive (buy)
        
        Then creating counting vector for each of the comment string, but for the string we will also need to remove special characters and non-word phrases (with some engineering and techniques)
        
        Then just fit the Feature X and Output y into the LR function in Python ML packages. (With L2 régression is necessary to make sure not overfitting)
        
        Cross validation to select the threshold for decision.
        
        70% for training, 20% for cross validation, and 10% for testing.
        
        How did you clean the data of amazon S3 product review data? Which columns did you use?
        
        The two columns I need are: rating, and common string.
        I remove all the special characters, and
    - - I worked on a large project by myself on building a supply chain Blockchain solution for Car components industry. At first everything went really well, and used the latest version of Hyperledger Fabric (at that time it’s v1.4) to finished the research project. 2 days before the due date.
        Just when I though I could spend more time to refine my project, the requirement for the project changed and let us to submit the result with version 1.2.
        This caused compatibility issue for my code, and then I spent 2 full days to try to figure out what was wrong. But there was nothing could help me, cause error was not intuitive at all.
        Eventually I couldn’t make the submission. Now thinking back, the biggest mistake I made here is not that I didn’t use the right version from beginning, but I didn’t ask for help from my peers.
        After the due date, I asked one of my friends that worked on the same project, and he could find the issue at first. But then he realized that my configuration fill looks a little bit different. Turns out the issue is that in version 1.2, the Profile for the network must be put in the bottom of the file, and v1.4 removed that requirement. Which caused me to didn’t make the dead line.
        So from that time, I start to change my working habit, and start to be willing to ask for help, and be generous to help others when they have any struggles.
        
        How do you configuration a Blockchain with Fabric?
  - - - Tell me about a time when you helped one of your teammates.
        
        Name time when you went out of your way to help someone.
        
        Answer
        
        When I first start to work on the Hyperledger Caliper GUI project, there are lots of configuration issue posted on the GitHub. Also everyday there are hundred of questions asked by people in the group. One of them is relating to the basic deployment of the base project that I want to work on. At that time I was still applying for the position, but I know that if I was lucky enough to get the position, I will eventually need to deploy that base software, so I started to deploy the Caliper CLI tool on my local.
        Turns out that it didn’t work on MacOS, so I started to use my local and cloud VM Linux Systems to deploy them. But non-of them fully resolve the issue. So I feel that I should spend some time to fix this bug, cause I want to work for this project, and I believe that the time I spend will be value able for this community.
        So I start to check the source code, and joined a few group to ask for questions. Eventually I worked together with another contributor to the project, and found the root of the lasting issue to install and configuration the Caliper CLI. Turns out that some packages that Caliper depends on needs to own higher level permission to run, which crushed the configuration process when they are saved in the root folder.
        So I kept doing some search online, and found that I can actually transport the global root packages to my personal folder, which I can change the ownership and access level there. I then wrote out a clear guide to resolve this issue with reference, and sent to the Rocket chat and WeChat group of Hyperledger Caliper developers.
        
        My Lessons
        
        This way I got some hands on experience even before I start to build my part of the project (bias on action);
        I helped my community to solve problems and earn their trust, which definitely helped me on collaborating with the development team later (earn trust);
        I learned more about the details of the tool and the issues in my project, so I can understand what's wrong earlier (learn and be curious + dive deep);
        I also feel like I'm responsible for the growth of the project and the community too, and I can feel that, even my small ripple efforts, can make a big difference in the long run (ownership).
        
        Pitfalls
        
        Think to find the topic first before start (< 3 sec)
        
        You need to have more clear understanding of your problem and solution! (Read the npm article about the solution)
        
        Solution
        
        S.O. Comprehensive Guide
        
        2 more items...
        
        NPM official document for changing global package directory to an already writable location (e.g. user home directory)
        
        You need to understand the contribution and your goal in here! (not clear at all when you say it)
  - - - Tell me about a time when you come up with a novel solution.
        
        Answer
        
        I worked on an e-commerce project for a client that was doing Asian food distribution business. His project requires uploading thousands of product when the online business is mature.
        In the end of the project there was an issue raised that I couldn’t solve it by simply coding front-end CSS scripts. The product images are perfectly high resolution and cropped out from background. But for some reason, the thumbnails of products and the products displayed in the page never align well.
        I tried to generate a thumbnail for each product image, but at some part the framework will need to synchronize the images used for thumbnail and product image. So it’s either we see only half part of the tomato ketch up in the thumbnail, or the product span three full pages tall in the product details page.
        Eventually I asked the customer’s permission to let me work on a separate software that can convert all the thousands of images at once without the need to buy a new software, or learn how to convert them one by one. I also tried to help my customer to save money on unnecessary investments
        I found that Linux actually have a software called ImageMagic, that includes a convert function to let me to reshape the size and adding background to make the image to 1:1 square. So I spent 3 hours to figure out how it works and built the software.
        But then I realized that it only works for some types of images, and it doesn’t allow user to easily draw and drop the folder to start the conversion. Also I realized that the images are not properly labels. What’s even more problematic is that some images are more than 10 MB large, but the WooCommerce framework only accept file under 2MB.
        So I decide to not sacrifie the long term benefit of the customer, and insist to make it perfect to handle all the above drop backs. I wrote a list to solve them one by one. And eventually, my software can finally works perfectly by just dragging the folder into the terminal, and start to generate a folder of picture with clear labels given by user. It also compress the size and convert the form of images to JPEG-2000, which is both small and clear.
        I tried to offer it to my customer, but since he is using Windows, which cannot run the bash code I wrote. So I offered to help him to convert all his images for free in the future.
        
        How was the image tool built?
        
        Ratio didn’t work at first, I have to filling the white spaces. Because the image is cropped out.
        
        The size is too large
        
        The image suffix type not match
        
        Offer for free, but customer was using Windows, so I offer him for free converting
        
        Saving money for customer from finding other people to redo the image or building softwares. I can do it.
        
        My lessons
        
        This way, I helped my customer to save money (frugality);
        solved the root problem he would be facing in the future (dive deep);
        invented something and simplified my work (invent and simplify);
        earned trust from him (earn trust);
        and learned some thing new that can explore more and helping more people in the future (curious and learning).
    - - Have you ever been in a situation where you had to make a choice amount a few options, but did not have a lot of time to explore each option? (Tech Stack for Caliper GUI)
        
        Tell me about a time when you had multiple solutions and you had to select an optimal one.
    - - After I finished my summer internship project, I immediately applied to be a guest speaker for my project in the Hyperledger Global Forum in the March this year, so that i can get direct feedback from my end users that care about this product. I also want to understand my users more, such as how they select frameworks in Hyperledger, and what are the issues they are encountering that I can resolve.
        And I was lucky enough to be selected to do this presentation. In there I met almost the largest amount of supporter to the Hyperledger community, and I feel more motivated to contribute more to this community after I heart the feedback and questions from them. (Run on Sawtooth, and not just Fabric: deploy on cloud with Microservices, so that update and usage are easy. Cause all the configuration are update int really fast)
        That also makes me to think big about the future for this app. What if we can host the benchmark service on serverless architecture, and allow anyone to test any blockchain in the world. That would save everyone’s time.
        So now I already start to build my API with docker, and hope to convert it to Microservices first. Also I already talked with several of the main contributors, and they think I can give it a try first.
        
        User are diverse: hotel manager startups that only interested in the performances
        
        User need new features and compatibilities, the version update is fast, and config change fast: inspiration -> to the cloud and Microservices, instead of making it a local application. (Faster update and accurate configuration files, and less trough in configuration for general users)
    - - Answer
        
        Hyperledger Caliper GUI by Hyperledger And Linux foundation (Configuration file + Visualization) + (Real time visualization with Socket.io)
        
        How did the socket.io works
        
        Because the connection was bidirectional, so whenever the update comes in, I can emit the change and save information to the interface (this will update the state in the front end)
        
        Ownership: I want to make sure that the project is start right, so I make sure that I can make it perfect.
        
        Customer Obsession: I read about how to tell good story with data, because I want to make sure that the graph is intuitive and useful.
        
        I added the file upload feature in the dashboard and allow people to chose to generate file or use the default.
        
        Everything is from scratch, and I hope that the design can be more intuitive.
    - - Tell me about a time where you did not know something and how you tackled it?
        
        Answer (Learn and Be Curious)
        
        I was attracted by blockchain technology in my senior year, and so I did lots of interesting research with professors in this field.
        I learned to build non-fungible token with Solidity on Ethereum Blockchain. But actually I’m more intrigued by those innovative attacks people made to the blockchain.
        I picked a few to implement by myself and ran on the testnet, so I can check without risking losing real money.
        The reentrency attack is really cool, and that’s the first time I realized that simple mistake can easily be fixed, but can also be used to steal millions of dollars without people notice.
        
        How the reentrancy attack works:
        (1) The victim contract has a transfer function;
        (2) And the malicious contract will have a fallback function implemented to accept payments;
        (3) If the victim contract forget to update the amount of malicious contract before calling the callback function to transfer, then the attacker can simply call the transfer function recursively in the fallback function. (Which eventually can drain all the saving in the victim contract)
        
        Access Control:
        (1) The wallet implementation can cause issue too. If the constructor is public, then anyone can call the instantiate function, and be the owner (public key address) of the wallet.
        (2) The owner is normally saved as a public key address, and once that is controlled by malicious users, fund saved in the wallet can be manipulated in whatever way they want.
        
        Withdraw under flow
        (1) The withdraw function sometimes only check if the balance - requestedAmount is positive;
        (2) That means if attacker give a super large number, then it could potentially under flow the integer, and then get a huge amount of money from the victim contract.
      - ISSUE 1: Realized issue of ERC20, i.e. lack of tx event handling.
        
        When you send an Ether to a contract that implemented ERC20 interface, it doesn't require the contract to verify if the incoming call is a transaction.
        That means if the token of ERC20 didn't not implement a payable interface function, then the sent token will be stuck in the contract, and not one can free them. (that means they are lost)
        
        Solution: Implement the transfer function that support the receiver fallback function when the transaction is failed.
      - ISSUE 2: Double spending by the Approve and sendFrom methods
        
        Alice gave Box (attacker) N token allowance.
        
        Then Alice decide to change the allowance to M.
        
        Bob noticed this and transferred the initial allowed N to Carol.
        
        Then when the new allowance M is mined, Bob transfer the M to Carol again. Thus in total Bob transferred "N + M" to Carol.
        
        And there is no way to tell that Bob made the transaction, since the transaction log didn't show the address of Bob.
        
        Solution: Including the current value for sending verification for each account.
  - - - Lessions I learned
        
        I like the new challenges, and is willing to explore more by solving problems (lean and be curious);
        I also willing to help each other and think that everyone is very similar, and by understanding the needs others and helping them can help me to grow and learn more too. Because others problem are also my problem that I need to face at some point in my life (ownership + customer obsession);
        I feel satisfied to take action and dive deep into new fields,
        so I can understand the needs of people in there and improve their experience with my efforts (change the world) (customer obsession + dive deep + think big).