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    Academic journals practices

    Nothing special. The same content in every review invitation.
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    Literature database?

    There's RePEc for economics:
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    Academic journals practices

    This can be a general thread that others may discuss their experiences. I have a question to which I couldn't readily find an answer: What does it mean when the editor(in-chief, if it makes a difference) sends you papers to review often, like once a month? The editor even sends that person two...
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    Developer of the KAPSARC Energy Model...

    Developer of the KAPSARC Energy Model:
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    Iron and steel industry flows: A question

    After some further reading/review, this is the latest materials flow schematic I'm going with:
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    Iron and steel industry flows: A question

    Hello, I have a general question for the flows of steel-making up to the casting process. Is the general flow depicted by the image correct? This specific process relies on natural gas reforming to produce H2, which is then used to reduce iron ore. Are there any corrections that I have to make?
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    Editors of academic journals - Question

    What does it mean when a journal constantly changes managing editors for a revised submission? A journal initially handed down a minor revision for a paper. I became a reviewer after the revision was complete, and saw many shortcomings or mistakes, so I recommended a major revision. It's been a...
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    The merger of engineering and economics

    There is this prevailing idea in the energy economics discipline that engineering and engineers are "not useful". That is at least how I have been introduced. See, I'm an engineer by training, but I've picked up energy economics by trade. So my boss once introduced several colleagues and I by...
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    The merger of engineering and economics

    I don't understand the last sentence. Why can't they meet? We live a multidisciplinary universe, where everything is influencing our decisions.
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    The merger of engineering and economics

    I couldn't fit it in the title, but I think the merger of engineering and economics is going to be important going forward. I feel most economists look down on engineering economics (just thinking of variable/fixed operational costs and investment costs, etc), and most engineers think that...
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    What's the general perception of the International Journal of Greenhouse Gas Control

    The international Journal of Greenhouse Gas Control. It has an Impact Factor of around 4, but what's the perception? Is it respected? Is it considered a good journal? There isn't a qualitative judgment online. My boss seems to look down on it, but it has a good impact factor.
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    Solving the heat equation with complicated boundary conditions

    Chester, thanks for your help, but I may just go ahead and simplify the BCs such that I use a sol-air temperature rather than explicitly include radiation effects. I've just solved the problem where I have 1-D space with one end's temperature fixed to zero and the other has convection term...
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    Solving the heat equation with complicated boundary conditions

    This is a problem of personal interest. The boundary conditions are not the same on both sides, and the heat fluxes on the boundaries contain radiation, solar, and convective components. Radiation is 4th order in T. The convective terms contain T raised to the third power (empirical correlation...
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    Solving the heat equation with complicated boundary conditions

    Correct. The heat fluxes at the boundaries are dependent on temperatures at the boundaries, and they vary with time. This is an example of what the heat flux would like: q''(t)=constant*(T(0,t)^4-Toutdoor(t)^4)... where T(0,t) is unknown and Toutdoor(t) is known.
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    Solving the heat equation with complicated boundary conditions

    The actual boundary conditions of interest specify the heat fluxes; however, the heat fluxes are dependent on the temperatures on the boundaries, which are also unknown. I just also include T(0,t) and T(L,t) being non-zero and positive. Is it wrong of me to impose those Dirichlet conditions...
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    Solving the heat equation with complicated boundary conditions

    Hi, it is easy solving these PDEs with the idealized homogeneous BCs they throw out in class, but I am having some difficulty solving the transient problem posed in the images below. I have tried working through it, but I don't have confidence in the result. I overlook the solution when the...
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    MATLAB Matlab - ADI Method Code

    I finally figured it out... I believe, at least. I'll go ahead and post the code for reference for future visitors who may run into the same issues. It seems to converge to second-order accuracy with larger and larger mesh size. Other...
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    MATLAB Matlab - ADI Method Code

    Hi, I've been having some difficulty with Matlab. I keep getting confused with the indexing and the loops. To set up the code, I am trying to implement the ADI method for a 2-D heat equation (u_t=u_xx+u_yy+f(x,y,t)). I have Dirichlet boundary conditions on the left, upper, and lower...
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    Ideal Vortex

    I need to find the circulation for a flow in a pipe. I'm using the velocity in the angular direction (cylindrical coordinate system). Am I right in thinking that an ideal vortex is one where there is no vorticity? That would mean there is no circulation. It's strange, because the velocity is...
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    Materials Question

    You can find the mass density of the elements. You know Avogadro's Number. Use the density definition of mass over volume.
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    Deriving Compatibility Conditions for Differential Equations

    I'm not sure if my thought process is correct. I basically looked at 1-D and 2-D self-adjoint problems to see what conditions were imposed on them, and tried to translate over to this problem. Can somebody tell me if I'm correct? Or at least have the right idea? I have my work linked below to...
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    Index Notation

    I have a general question about index notation. For an arbitrary quantity, a, "a" denotes a scalar quantity. "a_i" denotes a vector. "a_ij" denotes a 2nd-order tensor. So, if I have something like "a_i*e_ij*b_j" Would this be like multiplying an nx1 vector, an mxm matrix, and an Lx1 vector...
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    Lifting a mass problem

    Draw a free body diagram, and solve the problem as you see the forces there (gravity, upward acceleration included). The acceleration would be modified.
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    One dimensional motion problem

    Try using a positive value for g. Since when you ultimately calculate time, using a negative value would result in a negative value under the square root. Edit: Strike out what I said.
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    Solving a System of PDE's Using Maple

    I am solving a coupled system of non-linear PDE's. What am I doing wrong in the procedure? It says, "Error, (in pdsolve/sys) too many arguments; some or all of the following are wrong: [[k(x, y), p(x, y)], {diff(k(x, y), y) = 0, diff(p(x, y), y) = 0}]". I am trying to imposed zero boundary...
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    Has Anybody Been in this Situation Before? (Masters Thesis/Advisor)

    My questions to him were questions that anybody in theoretical heat transfer would know. At least the methodology behind my calculations. I love the guy, but I'm worried now that neither he or I know where to go from here. I have all summer with no courses to dedicate my time to the project...
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    Has Anybody Been in this Situation Before? (Masters Thesis/Advisor)

    I'm working on a project with a professor for my MS. It's computational, and I am currently stuck at a critical point. I can physically justify some assumptions and get the model to work, but I can't do so mathematically. They would be mathematically arbitrary. I'm working to resolve this...
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    Differentiation Variable

    I'm working out some problems, and I'm ending up with a term similar to the following: du/d(y/u) I'm differentiating with respect to y/u. Both y and u are variables. How can I divide that up to represent differentiation with just one variable (Even if it means expanding the term)? Is it...
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    Mathematical notation: 2.00 E + 00 and 1.00 E + 01 ?

    You mean in this form... 2.00,10.0 ?
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    Fortran Why Doesn't Fortran Recognize Small Numbers?

    Rather than make a new thread, I figured I'd ask here. Is there anyway to define functions after the input type statements? For example, f(x)=sin(x). I want to redefine f(x) as I go along the program. Thanks.
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    Level of Independent Thought for a Ph.D. Student

    I think it depends on the professor and research subject. Even for masters students. I've had an advisor who would never help me. He would always tell me to figure it out. My current advisor and I always discuss problems I have. I can always corroborate information with him, and we talk about...
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    Estimate the density of the water

    In 6 km, the change in pressure is significant. Here's something to get you started: Use the equation, B=dP/(d(rho)/rho) Manipulate and integrate, integral of (d(rho)/rho) = integral of (dP/B) That results in, ln(rho2/rho1)=exp((P2-P1)/B) Where you can say state 1 is the surface, and...
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    Turbulent Natural Convection with Condensation

    Hello, I'm thinking about a natural convection problem where you have turbulent flow on a vertical wall. It's compressible flow, and it's a two-phase problem. You have two boundary layers, one for the air-vapor mixture, and one for the condensate. The question I'm pondering is this...
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    Fortran Why Doesn't Fortran Recognize Small Numbers?

    Ah double precision statements. I didn't think of that. I was trying to use periods, which weren't working, but I've seen people use them for that purpose. Thank you. I read up on double precision statements and it was simple enough to incorporate. That worked.
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    Chemical energy in the runner's body

    That is a bad question. There are various forms of energy in that given situation. Both A and C are correct. There's heat transfer going on between the body and the ambient environment. However, there's electrical energy, kinetic energy, and chemical energy involved, as well. Muscular...
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    Fortran Why Doesn't Fortran Recognize Small Numbers?

    We're not talking very small. Is it the compiler? I'm using gfortran. An example would be: f(y)=1E-5*(y**3) For f(40), that should be 0.64. When I compile and execute, however, it displays 0's. If I make the coefficient 1, the result does come out to be correct. I have an old...
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    Fortran (3I3,F9.6) Fortran source code

    Since he has had his question answered, and my question relates to this topic, I'll post my question here. I'm constrained to 72 columns to input my code. How do I input a function in multiple lines? e.g: f(y)=sin(y)+cos(y) I have tried: f(y)=sin(y) f(y)=f(y)+cos(y) The...
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    COMSOL Multiphyiscs

    Just realized I should add this... I have to impose a BC on the function itself and its derivative. So I have to use a Dirichlet BC. If it were just the derivative, I could use a Neumann, but I have to impose both.
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    COMSOL Multiphyiscs

    Homework Statement How do I set a slope-matching condition in COMSOL? Homework Equations u1x=u2x. The Attempt at a Solution I have used the Dirichlet BC type. I have multiplied and divided by n, the number of equations, on either side of the boundary.
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    How is Finite Difference Method?

    I'm going to take a finite difference linear and non-linear PDE course next semester. I'm wondering how enjoyable the material is, and how difficult it may be. I'm actually looking forward to the fact there may only be one test throughout the semester, if any, and it's a mid-term. The rest of...
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    Fortran I'm Having a lot of Problems with Fortran (77)

    By the way Math, what compiler do you use? For this initial practice run, I spent a lot of time going through compilers. I ran into this one called PGI Fortran Workstation. It's the one I used for this program. In just one command line in Command Prompt, it gave me an executable file...
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    Fortran I'm Having a lot of Problems with Fortran (77)

    Thanks a lot! Your help was great. It worked. I had to also include a "go to" statement so that the *.exe file generated wouldn't close on me immediately after the solutions were output. I also added some "print" statements to simplify input and data recognition. Good results too. Here...
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    Fortran I'm Having a lot of Problems with Fortran (77)

    It gives me problems with the function. "Assignment operation illegal to external procedure fun" Then it gives me the line in which the function is written. I went online to find examples of how to input functions in F77, but other methods I've tried resulted in more errors in relation to the...
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    Fortran I'm Having a lot of Problems with Fortran (77)

    If you don't mind to provide further assistance, I would appreciate it if you checked over my program again. I finally found a compiler that will work. It's standalone though. I can't seem to integrate it with Eclipse. It gives back a message saying I have 1 severe error. I'm trying to...
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    Fortran I'm Having a lot of Problems with Fortran (77)

    Thanks a lot. I really appreciate it.
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    Fortran I'm Having a lot of Problems with Fortran (77)

    I don't think it's the program; I have it shown below. Sure it's not the most memory-efficient, but that's not my objective right now. I'm just trying to get a simple program to work. I was finally able to get a makefile generated automatically, but now it can't launch it whenever I use the...
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    Is CCleaner safe to use?

    Yes it is. Just don't delete registry entries you may want to keep. It's good to erase data collected by the browser or downloaded manually.
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    Fortran I'm Having a lot of Problems with Fortran (77)

    I'm new to this language, and my programming experience is limited (I've only done Assembly). My issues do not necessarily lie in the coding itself, but in the compiling and building. I'm using Eclipse, on which I installed Photran. The syntax recognition and formatting of the GUI is very...
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    1D COMSOL Domain Implementation

    I think I may have figured it out. I'll use it and see how the results go. I'm trying to have 3 separate PDE models, and activating each one in one of the subdomains.
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    1D COMSOL Domain Implementation

    Hello, This is the first time I'm using COMSOL on a problem where I have multiple subdomains within the domain. Previously, I have only been using one domain/one set of equations/Two global sets of BC's. I've been having a hard time thinking of a solution to my problem. I have 3...