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Showing posts from 2012

Advanced Prediction Method for Quantum Efficiency of OPV Devices

Advanced simulation for organic photo-voltaic (OPV) In order to predict the quantum efficiency of a organic photo-voltaic (OPV) devices, molecular-level modelling and simulation approach can be used.  The three computation parts are calculated to predict the quantum efficiency of organic photo-voltaic (OPV) devices. The morphology modelling part, exciton dissociation part and charge transport part are the three important parts to be modelled for performance evaluation.  We focus on a bulk hetero-junction (BHJ) OPV devices since it is known to achieve high quantum efficiency because of accelerating exciton dissociation efficiency.  Morphology modeling It has been known that the performance of organic material device is highly relied on morphology of organic material layers. In particular, the domain size and the percolation paths in morphology of active layers are critical factors to determine the performance of the organic photovoltaic device. Exciton dissociation The genera

Long text writing in English [with correction]

Original sentence, James S. Kim (me) It is easier to write short sentence in English here in social network. However, it is not easy to write a long sentences. Even in papers, I can write a long sentences and a long essay in Korean but It it really hard to write a long text and a long documents in English. In order to be a good paper, we need to have a time to revise it but the revision is not a simple task. Therefore, the exercise is greatly important and almost essential for people to be a great writer in English as an non native speaker. Revised Sentences,  Stephen Dickson It is easier to write short sentence in English here in social network. However, it is not easy to write a long sentence, even in papers. I can write a long sentence and a long essay in Korean but it is really hard to write a long text and a long documents in English. In order to be a good paper we need to have a time to revise, but the revision is not a simple task. Therefore, the exercise is greatly

Windows Live Writer

I’m now using the windows live writer for posting an article in a blog. I’m checking whether it is convenient or not compared to internal blog editors. As It is not directly connect to the blog site, additional features are unable to support but it has a strong advantage that it is similar to conventional documentation tools such as the MS-word. When I write my document in www.blogger.com, it is also convenient to use the windows live writer.   l am writing by my hand now.

How to load current article in the widows live writer (ver2.0)

In my memory, I have loaded already uploaded articles here in the local writer. Sometimes, I want to edit old articles in order to improve the quality or to revise some typos. If I want to do it in the local editor, I need to have an ability to load old articles in my blog. In this editor, I can not use spelling checker, which is nowadays almost necessary to write a document. I found now that there is option which enables real time spell checking. The uploading is successful. I can see this article in my online blog, which offers almost same format to the format written during editing. Moreover, it is very interesting that I can revise article here and upload it as update version automatically. I realize that it is not allowed to write a document in Google doc in order to upload to a blog automatically. I want to know whether there is an online document system which allows to upload to a blog site automatically. If it is possible, it will vey convenient for people who want to writ

An analog way to collaborate programming coding with friend

I have tried a similar way with another friend so long previously to write a code collaboratively.  At that time, I'm good at writing a code while my colleague is good at writing in English, relatively each other. We wanted to write an English paper about the computer simulation research on wireless communications. Even if he is good at English, he also wanted to learn programming language, which is at that time, Matlab. Note that Matlab is one of the popular language and environment for numerical computation. He can write Matlab code freely quite much less than me. I checked his codes and give my comments on it. I remember that he looked happy when I gave my comments. Interestingly, I didn't realize that he was learning and teaching simultaneously with me by give-and-take fashion even if it wasn't explicitly expressed. Because of that stable formation, we was so happy together. I met similar situation now with another colleague. He is a physicist. I'm ve

Why does MIT select Python for robot programming?

I found today that MIT selects python for its undergraduate CS programing language. Originally scheme is used. Read Quote of Hiroshi Ono's answer to Artificial Intelligence: Is learning python instead of C++ a good introduction to programming languages in middle of CS/AI theory? on Quora

Mathematical Modeling and Parameter Extraction

James S. Kim - Google+ This is the time for me to focus on what I need to do. From the last Saturday we enjoy national holidays. Now this is time to prepare for proper working after not short holidays. I'll make some Python classes which will help to make my new model. My new model will be developed based on the analyzed scientific image. I have thought that the parameters must be extracted first to generate a new model. Now, I realize that both tasks must perform simultaneously. Now I build a simple model and a extract parameters and compare between the modeling results with the extracted parameters and the image value. In short, my model will show similar image using the extracted parameters and the modeled image and the real image will be compared. The comparison can be done by second order statistics such as mean square difference between the two results with respect to the extracted parameters. Moreover, the extracted parameters can be optimized in the d

Between science and computing

I'm really wondering whether computational science is computing or science. I think that 4th generation science will be similar to the case of recent engineering, Engineering has been enhanced greatly recently because of IT power. Like it, science can be much enhanced by the use of IT power. is there any kindness programmer who can talk me the difference between Python and Ruby. I think Python is more appropriate for scientific computation while Ruby is more close to web applications. As difference between westerns and orientals, science and management are important for each areas more than the other, respectively.

Power of iPython

Currently, I started to use iPython command line, which is so convenient and much compatible with the commercial numerical simulation tool.  Since the libraries can be tested and used in the command line, iPython can perform better results than any other methods including compiled language systems.  Each function and each class can be tested online and instantly. We can feel the functions and the classes by the directly use in the command line. Our mind becomes to be emotionally familiar with generated codes. Our brains, also, will remembers each generated codes. Therefore, the probability to use the same codes later becomes much higher. Whenever command line interactive systems such as iPython are used, there are usually two problems. First, meaning function naming is not easy for each revised functions. Second, the number of the required input parameters for newly generated functions are too many, which results in not to be useful in command line keywords. Therefore, the interactiv

Move over graphene, silicene is the new star material - physics-math - 29 April 2012 - New Scientist

Move over graphene, silicene is the new star material - physics-math - 29 April 2012 - New Scientist

Why is Python so powerful for scientific programming

How can free software tools be better than commercial software tools? Currently, I'm using Python as a scientific programming tool. Whenever I have used several free tools for scientific programming previously, I can not hide my regreat since free tools have always important disadvatages. Especailly, there is usually less documentation to use. However, rightnow I found that some free tools have both high compatibility with commercial best tools and better documentations to use. One of examples in scientific programming is Python with numpy, matplotlib libraries. In Python, similar to the competitive commercial tool, debugging environment is avaliable if free Eclipse with PyDev is used. Moreover, spyder offers wonderful indegrated editting environment. Another supporing environment is iPython with a option of pylab. It supports very wonderful scripting environment to support plot online. For python expert, it will be the best environment to test and run his scientific codes.

Template document is automatically saved in blogger.com

When I try to use this blogger.com, the template document without any text is also saved automatically. Therefore, I need to remove or rewritten later on. 

Difficult to revise a previous document

It  is better to write a new documentation than revise original document. 

At staring new writing

When I start to write my thought. There is no reconsideration point. I just start to write any thing in my mind. Computational science is interesting research issue. 

Developing MIMO Classes in Python

I am writing a Python codes for developing MIMO classes. Up to now, I have written my simulation codes for MIMO in Matlab. Recently, I realize that there is limitation to apply object oriented concept in Matlab programming compared to other OOP oriented languages such as Python. I now made my mind to write python codes for communication system simulations including MIMO algorithms. MIMO algorithms can be implemented by a Python code based on numpy, scipy as well as matplotlib. I found that now matplotlib offers various plotting tools, such as 2D plots, 3D plots, animation and even, saving animation pictures as mpeg files. [Parallel Processing] I found that Python also supports parallel computing for SMP, MPI and GPU systems. The related toolbox is PP. I guess that there is a computation engine supporting parallel processing.

Do you use the Google toolbar?

I didn't use the Google toolbar up to now since I want to make a web browser as simple and fast as possible by not allowing additional tools. I started to use the Google toolbar in order share bookmarks between different web browsers. Before I use it more in frequent, I want to know how many people use this toolbar in the world. If there are many people who use it, it means that the tool is useful. Moreover, if I can know why people want to use the Google toolbar for their other web browsers, it will be helpful for me to exploit the advantages of the Google toolbar quickly.

I like to take a care of dogs

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Lupine , a photo by Blazingstar on Flickr. I like a dog. When I was young, our family feed a number of dogs. We also had cats. To my memory cats were more difficult to feed than dogs. My brother and sister like dogs and cats more than me. One of the reason which I can remember now why they like dogs and cats more than me is that they are much younger than me during that time. 

Is a tablet PC useful for writing a blog article?

I'm testing now whether the tablet PC can be useful to write a blog. To my experience, it is almost no problem to write a blog in a note PC but I'm wonder that it is also okay to write a blog in an electric pad.

Is Wiki-type documentation always useful

I have been used wiki for my idea documentation. It is powerful and convenient to write a thought because it offers an highly easy hyper-linking function among the related items. After I have been using it, I eventually realize there are not only advantages but also disadvantages because of its convenience. In particular, it have been bad to improve my long text writing capability, especially writing not in the wiki supported systems or cases. Since Wiki is a new documentation system, there are still many other type documentation systems including technical and research paper publishing systems. It can be explained without considering convenient hyper linking functions. It is usually divided to several parts, which includes introduction, main, conclusion. In the wiki based system, the introduction and the conclusion parts are described shortly since readers are coming to new wiki article from the previous article, where the sufficient information is provided. 

kMC for OPV Simulations in the Python Environment

The kinetic Monte Carlo (kMC) algorithm with first reaction method (FRM) can be appiled for the charge transport simulation of the organic photovoltaic cells. kMC can be used for all three parts which are modelings for morphology generation, exciton dissociation and charge injection/extraction. 1. Morpology Modeling  For morphology modeling, the Ising Hamiltonian method can be used. First, random morphology is generated by applying random position p and n materials. If the size of sites is L * L * L, around halft sites ~ L * L * L /2 are set to p materials such as +1 for each element of the L * L * L morphology matrix while the other half sites are set to n materials such as -1, Note that the total number of p-material and n-materials sites must be equal to the total number of sites, which is L * L * L. That is, any site is belonging to either p or n-material. 2. Exciton Dissociation Modeling Exciton dissociation can also be modeled by kMC algorithm with the first reaction met

Kinetic Monte Carlo

The kinetic Monte Carlo (kMC) is a simulation method for Physics and Chemistry. Monte Calo (MC) is a widely using mathematical method for simulation, while KMC is especially useful for dynamic system simulations. It includes a timing factor

Writing by a electric pen

l am writing using a electric pen. lt is interesting to write text. I like this glaxy note. Do you like it?

Best display technology for book reading

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Reference: http://www.i-programmer.info/news/152-epub/3642-apple-enters-the-digital-textbook-market.html In my opinion, for books more important is to increase readability by the use of advanced display technologies such as e-ink, mirasol. I'm now reading a book using kindle as well as direct books. Kindle is almost like a book while other display are difficult to read longtime in terms of both readability and time. LCD display takes large energy so that it becomes turning off in mobile devices. Hence, it is not easy to read a e-book in mobile devices unless I change the auto turning off model out. What do you think? Do you think current display type e-pads will be useful for book reading continuously? Or, do you also agree that new display technology becomes also mandatory for convenient book reading? One of E-pads for book reading.  kindle 9.7" which uses e-ink for long time displaying