Issues Definition and 407 Threads

I'm having trouble allocating memory for a dynamic two dimensional array in FORTRAN 90; the odd thing is that when I did the same thing using three on dimensional arrays instead of an array with the dimensions 3*x, I didn't have a problem. read (1,*) ndat1 !The first line of every file is...

Hi, I am designing a RFID rectifier. I am referring a IEEE paper for this purpose. The paper has shown results for both 130nm and 350nm technologies. I have chosen 180nm technology. So, I expected results in between the above technologies. To my surprise, the results are weird -...

I've tried to understand the theory of relativity several times and could never wrap my head around it. so i would like to make an offer here. i would like to chat with a physics professor online for about an hour over Skype. my discussion probably does not belong a serious physics forum which...

Before I switched to Opensuse 12.3, I was running Arch, and doing something like: g++ -o test -I ./include/ -L ./lib/ -ltcod -ltcodxx ./src/main.cpp with no problems occurring. Now, when I try to do that (with everything kept the exact same as when on Arch), I get...

This is a C++ class to be used for summation of doubles (floating point). It uses an array of 2048 doubles indexed by exponent to minimize rounding errors by only adding numbers that have the same exponent. NUM::NUM - array is cleared out when an instance of NUM is created NUM::clear() -...

Anyone find themselves going more organic these days? http://www.huffingtonpost.com/2013/04/25/roundup-herbicide-health-issues-disease_n_3156575.html Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases...

Hey everyone, I'm struggling with the summation notation for matrices and vector operations, multiplication in particular. Please refer to the image below where I've typed it all out in Word, its too cumbersome here and I want my meaning to be clear...

Hello, This topic is an open discussion around the technical, ethical and legal implications and issues behind high-level nuclear waste management. I am a designer working on a project aimed at exploring the future of nuclear waste, by proposing alternative ways of dealing with the issue. For...

Hi there, I am a long time reader of the Physics Forums, but a first time poster. The problem I am requesting assistance with stems from a problem in Reif's Fundamentals of Statistical and Thermal Physics. 7.16 An aqueous solution at room temperature T contains a small concentration of...

I am in the process of working on a 2 stroke motor that I am looking into converting to fuel injection. One thing in particular that I find with the 2 stroke is that is less efficient than than a 4 just because fuel mixture goes out the exhaust port while it is still open. Is there any ideas...

Homework Statement I feel like I am being told that there two different kinds of normal force. 1st. In grade 11 we were always told that normal force on an angle equals m*g*cosθ, where Fn equals the y-component, and θ is the angle between Fn and mg. 2nd. Now in university we are told...

Battery issues in Automotive! Hi guys, I'm required to write an essay about development of 'Automotive Power', with particular reference to the Batteries. So, I'm looking for some current issues on the batteries related to its development! Any idea?! Thanks

I am looking for ideas for a contemporary engineering issue to write a paper about and give a brief presentation on.

HIya, I am not actually sure why this is happening so was wondering if anyone can help. im running in photon mode and I am trying to generate a weight window. initially i think my splitting mesh was over done a little bit (ok too much say about 15 fine intervals in a 10cm region) and i...

Hi Everyone, I'm trying to find the initial speed of a motorcycle that was involved in an accident. The driver lost control and the bike dragged along the asphalt for some distance. I know several variables but my physics is not a strong suit to say the least. Any help would be much...

Hello Physics Forums! I need a bit of help. I'm aware that this is not a HW thread, but your help is greatly needed. This could be posed as a general discussion question if this is of any concern. An assignment requires that I have to do research of several contemporary issues in ISE...

I was working on my cloud chamber today, and I ran into two problems: A) It's not working :) To be more specific, I used compressed air to get the bottom extremely cold. The structure itself is a small plastic throw away cup, with a sponge with 91% alcohol stuck to the top. The bottom (the open...

Hi, all. My friend is teaching a physics class. She personally has worked out and LaTeXed solutions to many of the problems from the class text with the intention of posting them online so students can use them to study. I'm mildly concerned that this might violate some sort of copyright...

The atoms in a gas can be treated as classical particles if their de Broglie wavelength is much smaller than the average separation between the particles. Compare the average de Broglie wavelength and the average separation between the atoms in a container of monatomic helium gas at 1.00 atm...

Homework Statement Venturi effect nozzle.. Starts off at 100cm and goes down to 40cm. The flow rate of the gas is 2.23 m3/s. What is the average velocity at the beginning and end of the nozzle. Homework Equations Continuity Formula, Bernelli = Q = A1V1=A2V2 The Attempt at a...

Degrees Celcius to Farenheight, Conversion issues ! Homework Statement You work in a materials testing lab ad your boss tells you to increase the temperature of a sample by 41.7 degrees celcius. Theo nly thermometer you can find at your workbench reads in degrees fahrenheit. If the initial...

Having Issues in Physics II :( Hi all, This is my first post on these forums, although I have lurked here for a little while here and there and I have to say I greatly appreciate the helpful topics you guys post! I have used them to get more than a few problems done... haha. Anyway, the...

I wonder if theories concerning the foundations of quantum mechanics, quantum field theories, and relativity are the same as Beyond the Standard Model concerns. Quantum Gravity is trying to find theories that encompass both QM and GR. So perhaps this is the same as trying to find an foundational...

I don't have all of the info at my finger tips because I had to come to work and leave my comp at home, but here is my issue and I can post extra info if anyone has questions: I am working with a professor who has me running his code (C++) that links to gsl and lapack. Specifically, the code...

Example of medical issues against artificial contraceptives: The World Health Organization has classified oral contraceptives as an A-1 level carcinogen, which puts it on the cancer-causing level as asbestos and cigarettes...

So I've got a very strong GPA/CV, I've had quite a few professors tell me they'll write me good letters of recommendation, and I've got a solid 2 years of research experience with one (maybe two) publications. I'm doing my best to prepare for the GRE, all I have left to do is write my personal...

I have a Fortran (F77) code which I used to use at my previous institution that I am having trouble with at my new job. I used to compile it with ifort on computers running Fedora (14 if I recall correctly). At my new job they don't have ifort so I have had to revert to the use of g77 (f77) on...

First post. You guys have really been helping me out I am trying to do a course distance learning and often the course just doesn't give you enough help and the stuff on here has been great. I have had a look at previous posts but just can't seem to get my head round this one. The Problem:-...

I started using g++ and the command line on linux. In one section of my code, I provide a default argument for a function parameter. I'm just wondering why this sometimes brings up an error if i don't include -fpermissive when I'm compiling everything. As an example. This is the...

Homework Statement I am struggling with u-substitution. I understand that it essentially the undoing of the chain rule, but I don not get how to actually go about the procedure. I have this example from my textbook: \int4x\sqrt{x^{2}+1}dx It says that u=x^2+1 and that du/2=xdx. Where did they...

I can't get my dsi pro II to produce a live view image. I either get a black screen or a grey screen with pepper dots. I concede the possibility of operator ignorance.

QM seems something out of our everyday experience and to some it might seem unusual/weird/undeliverable/a hoax...yet... perhaps it actually solves some of the conundrums in classical physics Does QM solve/resolve a few philosophical issues in Physics? 1) Classical physics says that every event...

Problem with opticalmicroscopy of features near vertical sidewall of very deep trench Hi, I posted my question here: physicsforums.com/showthread.php?t=612780 but there may be more specialists here. Essentially I have a feature right next to a very deep vertical sidewall of the deep...

Is it a bug, or am I missing something obvious? \frac {L\times atm} {K\times mol} \frac {L\times atm} {K\times mol} Same if you don't use \times, on my computer it is rendered the same wrong way under Opera and under Chrome. This is image, not part of the text: ------------...

Hey all, First off, I'd like to mention that I am completely unfamiliar with this ANSYS and have been fighting with this program for last 2 and half weeks. Any feedback and help is greatly appreciated! Please refer to the photos attached for referral. My project currently involves analyzing...

Hello, I am currently enrolled in an introductory Computer Science course, and I've been having trouble with a Java/HTML project. I have been given the following code for a triangle applet to be linked in an HTML page I have to make: import java.awt.*; import java.applet.Applet; public...

QUESTION: WHAT DO YOU THINK THE ETHICAL ISSUES WOULD BE IN THIS SCENARIO QUESTION: WHAT WOULD BE THE IMPLICATIONS ON THE CODE OF ETHICS CASE: Laura’s Dilemma Laura Jenkins is a qualified environmental engineer who graduated from the University of Stoneybrook two years ago. Laura works...

I am developing a website in MVC3 for a financial training academy. The problem is that my client uses IE for testing the website. There were a lot of graphical issues but i solved most of them myself. Currently i am having problem with the styling of combobox, the comboxbox looks perfect in...

Hello, I am working a on a project to improve the thermal properties (heat capacity, thermal conductivity) of heat transfer fluids used in concentrated solar power (CSP). First a suitable base fluid is required, the higher the working temperature the better for thermal efficiency. Most of the...

I currently attend a community college and holding a 3.9 GPA...I realize I don't have many options in my state to transfer because the "good" schools are almost impossible to transfer into even with a 4.0 GPA and I don't know what other credentials they are looking for, and the other reason...

Sorry for my bad English and mostly for my bad Physics. For me it doesn't make any sense regarding the expansion of the Universe as a distant process, a sort of time&space machine which 'degulfs' more room for the known things to occupy. My guess is the expansion is happening here now at a...

I am considering making a yagi antenna for a wifi adapter and I have been warned about some possible side effects that I wanted confirmed or disproved.. I read somewhere that the 2.4GHz band also is the resonant frequency of water and is used by microwave ovens, but at a more powerful rate...

Homework Statement To save money you put $3000 at the end of each year in an annuity that pays 6.8% compounded annually. Use the formula for the value of an annuity. The Given Formula: A=P[(1+(r/n)nt)-1] ______________ (r/n) How much would be saved at the end of six years...

Hi I'm trying to convert m3/hr to kg/hr for a steam system operating at 14.5 barg and 1150 deg C. I was planning on using steam tables to get the specific volume but anywhere i look the temperature seems too high to have any values. Any suggestions of places that do have the values I'm...

Homework Statement A force F1 of magnitude 6.00 units acts on an object at the origin in a direction of 30.0° above the positive x-axis (Fig. P3.10). A second force F2 of magnitude 5.00 units acts on the object in the direction of the positive y axis. Find graphically the magnitude and...

Hello, I am pretty new to programming at all and am having some issues with working out why this program is not compiling: Program MAIN DO J = 1, 11 K = 10 + J P = 0.4 !POSITION OF MAXIMUM CAMBER AT 40% CHORD! M = FLOAT (J + 1)* 0.01...

Hello, I am new to the TI-Titanium and have run into a few rather simple obstacles that are keeping me from answering physics questions in the correct way. First off, by typing: \sqrt(5) the answer comes out to: =\sqrt(5) as opposed to 2.2360... (I believe this is a setting/mode issue)...

So i have to had my central heating fixed 6 times, my loo 3 times, the problem is i have to go through an answering service every time, how does one nail the contractors?

What is the fundamental knowledge that the average, or above-average physicist must possess? Put simply, even a subject as rudimentary as undergraduate level classical mechanics teems with so many formulae and so many derivations that I find it incredibly mind-boggling that a physicist should...

I have been following the situation about the complaints against NRC Chairman Gregory Jaczko by the four NRC Commissioners. From what I have seen and heard, I would think that the complaints are legit considering the credentials of the commissioners and the fact two are Democrat and other two...