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2013 Purdue Internship Summary

12/17/2015

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It is written long ago. But I thought I just need to put it somewhere.
​
From a more academic view  I described the work in Purdue. 

This summer I mainly focus on generalized formulation of impedance for two phase flow. For this piece of work, I have been receiving training of searching and summarizing literature, making scientific assumption and deriving equations for physical intuition. My first experience of independent modeling gave me incredible joy when I found the final results both interesting and meaningful. Brief summary of my research are included behind.

For modeling and simulation training, Dear Pierre taught me on how to do research efficiently and organized it on Linux platform. Open source programs works efficient on that it can be manually specified for diverse purpose and always repeatable with a script file. As a typical Windows user, this brings new aspect of my own profession. Also, as a post-doc, Pierre enriched my knowledge of what it takes to be a good PhD, like how to pick good advisor, choose research topic and find star point of research.

Besides simulation, during my stay form July.7th to Aug 21th, I have deep conversation and experiment observation opportunity with the help of Susmita, Suchi, Mercy, and Julian. Thank them for several important lessons and experiment tours. Especially, Birck Nano Center impressed me by its huge clean room and leading research topic. In Mercy’s experiment, contact angle are recorded automatically rather than picture-by-picture manual processing in Tsinghua. Experiment is much more standard and rigorous here, which gave me a better understanding of how good research are done. At the same time I updated my knowledge on the major challenge and solutions of electronic cooling, especially in the nano and micro scale. For the last two weeks, Hsien-chin's and I have discussion on combining mechanical device to enhance condensation, and I contribute to his proposals. Also, I had my first lesson on how to come up with proposals based on observation and analogy.

It’s my first time of being abroad and being in United States, but the atmosphere in CTRC makes me feel peace and people in CTRC make me feel at home. Hereby I want to present my highest gratitude to Pierre, who spared no effort taking care of my bothering and taught me a lot on how to be good researchers, though Linux is still annoying. And thank Justin for always being around offering important instructions. Finally I would thank Prof. Garimella for giving me such an opportunity in CTRC learning and researching with so many excellent people.


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Flew to Chicago at July 7th
Embracing Clear Air

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First day welcomed by CTRC! 
Thanks for all the members.
I love the feeling of being around with friends. And things turned out great with those guys.





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The workstation I have been working with . SWEET~

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Thank you Suchi,  for teaching me the particle method to improve the nucleation.

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My good pal, Pierre

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Thank you! Chinese Lunch Box.

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Cooking on my own. 

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Find out the Asian Graduate Students in Purdue ME. 

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A travel to San Diego.  
Mid-Way Museum is the most fantastic place making  boys like the army. A pity that there is no such great place in my childhood.

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产品,创新,工程 Products, Innovation, Engineering

8/7/2014

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转载请注明出处,作者:王乐天,网站www.letianwang.me
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以下是我对这个话题的一些思考,还在整理中,不尽完善。

1. 产品,人,社会
产品是一个具有结构的与人和环境交互的完整实体或者内容。

原本的社会,原本人和产品是分立的,产品和产品也是分立的,大家就像使用碗筷一样使用一些产品。但是现在社会的复杂条件下,有一些因素导致,产品,与人紧密地联系,形成一个复杂的系统。

首先,产品和人的联系增强。一方面设计要求用户体验和用户沟通增强,但这只是量变,质变在于后面一点。我们发现随着信息化的到来,大量的文化信息产品出现了,包括软件,网站,歌曲,视频,电影,这些“内容”或者说抽象点“信息”商品化电子化了。这样随之带来的一个很大影响,就是人们不再是用功能来评判一个产品,而是以“创新”“体验”这样的词汇来看待产品,其实也就是说,产品的功能就是给人创造“体验”,所以,人的因素大大强化。

此外,产品和产品的联系大大加强,internet+wireless串联或者正在串联很多设备,智能家居和课穿戴设备就是如此,其实从电脑-智能手机-智能穿戴设备+智能家居+智能汽车,这整个线路就是让信息流和网络渗透到生活中更小的细节,成为人的需求的自然延伸。随之而来的,就是产品间相互作用增强,形成一个网络。当然,不仅是信息沟通,由于设计过程的不断优化,设计理念的提升,产品本身直接的沟通也越来越多,从我们的一个家庭来看,宏观上说,现在就非常强调建筑物和整个环境的联合,微观山看,室内家居需要和整个环境融合。




另外,人与人之间的联系,通过互联网实体化,强化了。首先,我们在使用的人人网和QQ等,占领了沟通渠道不说,还使得大家共享了信息源,将友情分享的触角从原来生活上的帮助扩大到了信息。其次,大多网络产品反应的是群体的特征,比如大众点评告诉我们哪里吃饭好,嘀嘀打车告诉我们最近的司机在哪里。最后,最后代表性的,也就是集大成的终端,就是手机微信,即时沟通,分享咨询,吃饭购物,都紧紧地把你和其他人联系起来,将原本人与人之间虚无的联系,也通过互联网的数据,记录为白纸黑字的联系。

这种联系的形成,就导致,人也成为整个系统中的一个元素,而不仅仅是一个使用者。

所以,人,信息,产品是紧密地联系在一起的,构成一个socio-technical system,但是现在产品和人构成了这个复杂系统中有共同特性的一个node。

2.  创新是什么?

创新包含两层意思,创意和新。我们最初的认识,就是这个东西很新,这不管是爷爷奶奶叔叔阿姨都能感受的到。但是是否新就能带来创意,显然不是的。创意包含着更深的一层,其实就是一种更加合理的功能,一种更加美好的体验。传统意义上,这样就够了,但是,就我自己的一个体会,如果我们去分析一些成功的创新,其实还有一个因素。创新之所以能够呈现在我们面前,被人接受,它的成功这还需要它的传播性。传播性,简单联想可以得到的是信息和媒体的传播性,但是还有产品的传播性。



3. 工程

a.  工程研究

工程研究是人们发现工程能够使用的规律的过程,举一个例子:电池工艺、加工工艺是工程研究。我们如何让电池的储能量增加一倍?如何让更多的锂离子储存在这个狭小的空间内。需要化学家去试验加工,得到加工的规律,需要科学家去解释锂离子结合与脱除的机理,指导电池的工艺,最后,还需机械工程师分析电池的导热、流动与反应综合,预测电池的寿命与真实性能。

在这个过程中,我们建立模型,分析条件,通过实验或者树枝模拟,验证理论模型的正确性与参数的可靠性,得到宝贵的规律。这一过程是利用科学原理,发现适用于工程的规律和设计规则。

备用素材:

我在清华,一个20m直径的桶储存融融盐来储存太阳能的热,以便需要的时候来释放加热蒸汽发电,液体在石块之间流动,并且交换热量。这样我只是研究热量储存效率和我液体流动的不均匀性的关系。流体力学以及传热学,还有热力学。

实现这个过程的方法:是这些知识转化为一个模型,也就是一大堆方程。然后数学家想出一种离散的解法,计算机科学家把他整合在一个软件中,我们就可以使用软件设计了。

b.  工程产品

工程产品,是工程的一个零件或者零件的组合。也是我们日常中最多见的工程概念。设计一个工程产品的最终目标是整合各个部分的功能与结构,得到整个产品的功能和结构。这个产品具有相对独立的系统以及功能。

从一个iPad来说,工程产品就是电子器件、电池、显示屏、外壳这些东西的组合。本来每个部分都只有运算、供电、显示等功能,但是组合起来就成一个能够让我看电影,玩游戏的iPad。

c.       工程系统

我们所说的工程系统,则是最近才出现的一种形态。也就是说一系列工程产品组合在一起,组成的一个有机体实现人们一些更加复杂的需求。其中最好的两个例子,一还是我们的苹果,苹果的生态系统,第二就是Tesla电动车。

第一,对于苹果系统,我们使用iPhone,iPad,还有Mac Book,这三者之间能够互相传输文件,同步我们的习惯,并且外观具有一致性。同时,苹果还有很多的配件、smart cover、耳机、连接线、网线转化、电源转化器,还有最近出的魔声耳机等等,构成了一个产品链条。但是,更加深刻地看,工程系统还有还有iCloud,收藏我们的照片和文件,还有APP Store能够提供三者都需要的软件来源,这样的体系能够让大家更加舒适地体验一个系统带来优势,而这样的优势,是无法通过一个三星手机+一个三星平板+一个三星电脑实现的。因为只有系统地思考,才能得到系统的结果,才能对这个系统有所优化。最近苹果公司2014年的WDDC,提出了新的构架,能够让我们的一体化体验更加全面和舒适。

第二就是Tesla电动车,特斯拉之前的困难在于,它需要提供一个人们使用电动车的系统,从汽车的开发、设计,到美国各地的充电站、电池更换、保修各个层次的供应商链条都需要打通,还需要时间,所以说,Elon Musk的伟大就是在做一个看似不可能的事,做一个原本需要很多公司一起做的事情。


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转载请注明出处,作者:王乐天,网站www.letianwang.me
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Innovative Thinking and a Graph Mind 创新思维与图像思维

8/7/2014

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一次我和美院的一个女生聊天,说起来我虽然是工科男,但是图像思维比较强,画机械制图比较轻松,对于设计的审美也不错,属于非典型工科男。那个女生说了,哈哈,“我们的图像思维更加好了,我最怕什么算数字了,但是构思创作速度非常快”。想着我自己平时脑子比较活,到底和什么样的思维有关呢。我发现,音乐,绘画,舞蹈都是创意比较多的领域,算是创意的集中展示。初步的感觉是这些艺术形式大多是排列组合和寻找联系(模仿,模拟),这种思维与我们画画比较类似,尤其是小孩子画画,而不是我们之后科班出身的大人们的画画,所以我统称图像思维。似乎图像思维对我我们创新有非常大的意义。

我进一步思考,想找一些深层次的例子来支撑。为什么即使是编写程序如此逻辑化的过程,最理想的设计方案还是呈现为流程图。大家最喜欢的构思的方法还是画草图。所以希望讨论一下图像对于创意的产生的意义。

越来越感觉到创新的思维是图的思维,但是量化思维和图的思维到底可不可以在一个人身上共存?难道必须要求助于一个具有不同思维方式的partner?或者自己拥有人格分裂技能。对此的思考戛然而止,希望有朋友能够和我多多交流。



在此,我也记录下自己关于如何提高创意创新能力的几个方法:


1. 培养自己的图像思维,关联能力。以工程师为例,由于我们的日常课程大多都是围绕数理展开的,数量化的思维比较严重,所以经常有意识的去观察海报和画,能够提高我们对于图形和空间的感知能力。

2. 创意创新之旅,在旅途中观察。创意产生的一个步骤就是出于一个创新多元的环境中。在多元的环境中,你往往可以汲取创新的灵感,或者说是创新元素。我建议可以从多元的文化城市开始,在这些城市中行走,你可以领略到两种完全不同的文化,然后通过当下的对比体会到他们的不同,进而体会不同带来的解决问题不同的办法,艺术品不同的表达,最后产生。北京,香港,新加坡,美国纽约,以色列耶路撒冷,土耳其伊斯坦布尔。

目前排名前十的世界创业城市有美国硅谷,纽约,英国伦敦,加拿大多伦多,以色列特拉维夫,美国洛杉矶,新加坡,巴西圣保罗,印度班加罗尔。而我个人认为离我们较近的则是中国深圳,北京,台湾台北,新加坡。

3. 观察生活中事物的细微创新。拿起一个杯子,我们可以看这个杯子与这个牌子前一代杯子的不同,或者说自己常见的杯子的。找到这种不同,累积起来,你就会发现创新的其实是有规律的。

4. 多和不同专业、不同职业以及不同国籍的人交流,交流他们的主要的困难和擅长的工作,也交流一些习惯。从中可以看出很多人们处理不同问题的思维模式的不同。

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Recent Advance and Big Names in Complex System

5/25/2014

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Santa Fe Institute
Established for 30 years since 1984
From Chaos to Complexity: Where Arts and Science Meet

Mark Newman-Link

The small-world effect is a modern phenomenon


Duncan J. Watts
From Columbia to Microsoft

Robert Kleinberg
Cornell
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Statement of Purpose-Generalized Version

3/14/2014

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statement_of_purpose-genralized_version.pdf
File Size: 168 kb
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Research Summary Downlaods

3/14/2014

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applicant_research_update_summary_letian_wang.pdf
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Motivation Statement for PhD and Research

3/14/2014

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Note: I wish to state my reasons for applying PhD research. Recently I received a reminder from professors indicating I am more suitable for master program, I am surprised about why he would say so. After a scrutiny of my application material, I found it may come from my entrepreneurship experience and diverse interest. There are several reasons that I wish to pursue PhD research, which I failed to state explicitly on my SoP.
motivation_statement-_phd_and_research_letian_wang.pdf
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The reasons that drive me to pursue PhD

I liked to read about science magazines when I was young, so my parents booked 6 along my childhood. Since the first time I read about Scientific American Chinese Edition in 2006, I have been fascinated by the power of advanced technology. In high school, I found science is the drive behind the technology and I fell greatly attracted. After college, my goal is to shorten the marathon between researches and innovative technology. For example, I am impressed by the nano science but I found there is still a distance from systematic application. 

To achieve my goal, I think the first step would be building up my systematic thinking and gain insights into innovative research. At the same time, I tried to understand and learn to push forward the frontier. Finally, I start from my research domain to study and accelerate such transformation. These concerns drive me to purse a PhD research. I felt my heart calling when I found the research picture on world-class universities’ websites looks just the same as my 2006 Scientific American. So I can work on my childhood dream? It is unbelievable.

Specifically, I choose to became a PhD with following reasons. 
Firstly, it is about fulfilling my curiosity. Since my childhood, curiosity and innovation are two most important things in my life. I discovered the innovative role of hi-tech startup. It is important but not the first priority for me. In microscale, there are a lot of unique properties that will change our current understanding on energy conversion. We have no systematic understanding on this.

Secondly, I also love to build up my systematic thinking. I like to draw laws and conclusions when I am observing the world. But I found master student are not that curious about how the world works and deepening our understanding. Being a PhD is the best way to do so.

Thirdly, I found the PhD research can better shape my ability to overcome difficulty and challenge the impossible. So I am more interested in researching on the emerging field, micro scale transport for my coming years. For longer time, the spirit I raised in research can be used in my other experience.

For my entrepreneurship experience, as in my SoP "In the future, I want to be an entrepreneurial scientist." I want to be a scientist who have a spirit of entrepreneurship, that willing to explore the unknown field with most opportunity. 

For my diverse interest, I just offered a window to share my interest to all the professor, I think every people with curiosity of the world will have a lot of interesting findings from daily life or various fields. I know clearly the importance of focusing on one field, which you can tell from my continuous research updates on microscale transport

PhD plan:

1.      Lay solid foundation on quantum effects and statistical mechanics for micro/nano scale transport.
2.      Improve the multi-scale modeling and simulation. From senior design( degree paper), try to extend my understanding on using network method, heterogeneous modeling method(HMM) to link the nano information to macro modeling.
3.      Learn about nano fabrication in clean room for basic nano materials. CNT, grapheme, silicon tubes, etc.
4.      (Advanced) Research on novel nano/micro devices for thermal transport and energy conversion.


Career Objective: Teaching, Engineering Practice, or Research?

My lifelong goal is to shorten the marathon between researches and innovative products. Teaching is important for educating others to innovate, but it does not necessarily provide me enough authentic opportunities to create. Also, according to my current knowledge, the professional practice is requires innovation but basing on current technology, not directly from scientific discoveries. According to my interest in understanding Mother Nature and studying how discoveries becomes the technology. Being a researcher could satisfy my curiosity as well as the desire to innovate. Besides, considering my tendency to thinking in deep as well as taking challenges, I would choose research.

In the future, I would love to be a scientist exploring a field with rare people and probably working on an interdisciplinary direction. From my startup experience, I learnt to pinpoint a field with most opportunity and be less afraid of failure. I hope this can make me a better fit for challenging PhD topics


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Research Update No.7 (Mar 13th)

3/12/2014

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My degree paper topic is defined as the multi-scale thermal transport modeling for nanostructured electrodes. The major work is inspired by the process of my literature review of  nano material and the paper Combined Microstructure and Heat Conduction Modeling of Heterogeneous Interfaces and Materials . The content is listed below:

  1. Relate the micro structure to the transport properties for nano electrode. Understanding how specific nano structure like coating, core-shell, hierarchical will change the thermal transport.
  2. Choose appropriate parameter transmission framework (network, HMM and others) for micro to meso and macro. Now the candidate model is multi-scale network method.   
  3. Using macro scale simulation (COMSOL) to analyze how the micro and mesoscopic geo parameter will affect the whole battery performance.



Research Memos

1.    Multi-scale informatics

With the emerging of nano science, scientist collected a lot of interesting information from micro structures, which is  . However, the engineering paradigm is still macro modeling. How to accommodate the new information became a critical issue. I am building up the "multi-scale informatics" thinking.  my idea about material transport properties while doing senior design. I am trying to link the nano structure material transport properties to macro properties. But I just started and looking forward to discover more topics to talk about. 


2.   Complex system and design optimization Also , I am interested in thinking about engineering from complex system and using data analysis . Complexity is one of the major characteristics for the future technology development. Using data tools to facilitate science exploration and engineering design is my prospective for the future. As a consequence, I am reading about graph theories and applied them into a complex network analysis.  You may find it out on my web http://www.letianwang.me/network-analysis.html. I also came up with an idea using data to facilitate the electrode research for Lithium-ion battery: http://www.letianwang.me/engineering-design-for-nano-electrode.html


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Innovation metric for products-Phase 1 memo

3/1/2014

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Last two weeks, I have been working in SUTD (Singapore University of Technology and Design) with the supervision of Prof. Katja Otto. Our project is to develop a metric to measure the innovation degree of  various products. My work is first to be trained as an evaluator and then to improve the metric according to my training process and further data processing. 

Phase-1 Memo

Understanding The Products

After I studied the evaluation diagram developed by Prof. Otto and her colleagues, I draw a graph that shows a product can be abstracted as an structure that interact with the environment and user to offer some functionality. I also learnt the basic process of product design by going through some of your slide.

Innovation Have Patterns

Product evaluation takes much effort but it provides me with down-to-the-earth understanding on how people innovate. Innovative product has similar pattern in structure innovation and interaction innovation. I need more time to detail the patterns.


Background Matters How People Look at Products
The evaluation process of product is basing on the background of people in terms of his life experience and culture background. Though it cast obstacles to our evaluation, but for product marketing and  globalization it is meaningful. 

For product marketing, it is interesting to find the customers will not be informed about the novelty of products if they have no background knowledge about the products. Though the target customers are mostly those who have backgrounds, we are interested in how to expand the target customers, i.e to bring the out-of-circle customer getting interested.   So for mass media marketing, we should take the into account background introduction and customer comprehension. If company pay more attention to that, there will probably be less boring ADs on the TV.

For global products development, we could qualitatively explain in which chains will this take effect. Then if we are able to measure this discrepancy and measure its influence on different country's market performace, then we could shed lights on  multi-culture user based product design.

Why They Failed to Catch The Market?

By reading historical products, I found though they were so innovative at that time, not every product managed to catch the market as we wished. If we could locate these reasons, that will be meaningful. The reason may be that it could not manage to replace the functionality or availability of  the original counterpart, then it gradually lose its attraction as an innovation.
I think this point can be It can be detailed after we link the product performance to our evaluation. More work is in need.
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Idea-Engineering Design Research For Nano Electrode

2/26/2014

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Picture
 Various Nanostructure for Electrodes
-Coating
-Core-shell
-Encapsulation

Nano science is now investigated by a large amount of researchers in Chemistry, Physics, Materials Science and Mechanical Engineering. etc. Lithium ion battery is one of field catches most nano scientists's attention. Nano electrode is the core of innovation. According to Web of Science, there are 624 research papers focus on "nano+electrode+lithium-ion" topic. 

I respect material scientist in the aspect that they have invented a large amount of electrode with different materials, geometries, and combination methods. Then these electrodes are labeled with different features. From my observation, most material scientists' work on electrode include material fabrication, characterization and performance test.  The focus lies on the fabrication and characterization of nano electrode. The mechanism study is limited and only based on certain set of electrodes. What's more there is no systematic research on the functionality of different features. Which feature is more important? How could we locate the optimal? When I was doing literature review, those questions bother me a lot. 

A natural thinking is could we use statistical method (like regression) and literature data to locate the powerful features, to find out which of  nanowire and nano particle is more useful? Review papers offered a half-processed data pool, and a larger data pool would be the 624 papers emerging last year. To test the statistical model, we may use limited sets of data with limited features. For example, I am studying the silicon-carbon anodes for LIB.  Then gradually, we move to the multi-dimensional design, with varying materials, geometries, combinations and even fabrication process. To enhance the robustness with most simple model, we need to have a pre-selection of the sensitive features, which might be done machine learning and data mining methods (like rough set) for larger data pool. The functionality model will offer the weight of different functionality to the performance, which may shed light on the explanation of the mechanism. 

After we had the basic understanding of the functionality, we would also get interested in how could we generate new electrode with the data pool. The design of electrode is actually a discrete multi-variable optimal problem. If the variables are limited, it can be reached by a searching method. But without  that, we could only try different combinations. I think we could introduce a framework of using idea matrix and innovation operator to genetically generate the new electrodes. This part is still not well-thought especially when I am doing dual projects already. 
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