<HTML> <HEAD> <META NAME="GENERATOR" CONTENT="Adobe PageMill 2.0 Mac"> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <TITLE>Special menu</TITLE> <LINK REV="made" HREF="mailto:%20chappell@citrus.ucr.edu"> <script language="JavaScript"> javascript: resizeTo(750,900) </script> <style> /*---- CROSS BROWSER DROPDOWN MENU ----*/ ul#nav {margin: 6 0 0 10px;} ul.drop a { display:block; color: #000080; font-family: Arial; font-size: 16px; text-decoration: none;} ul.drop, ul.drop li, ul.drop ul { list-style: none; margin: 0; padding: 0; border: 1px solid #fff; background: #e0e0e0; color: #0000FF;} ul.drop { position: relative; z-index: 597; float: left; } ul.drop li { float: left; line-height: 1.3em; vertical-align: middle; zoom: 1; padding: 2px 15px; } ul.drop li.hover, ul.drop li:hover { position: relative; z-index: 599; cursor: default; background: #20b2aa; } ul.drop ul { visibility: hidden; position: absolute; top: 100%; left: 0; z-index: 598; width: 245px; background: #555; border: 1px solid #fff; } ul.drop ul li { float: none; } ul.drop ul ul { top: -2px; left: 100%; } ul.drop li:hover > ul { visibility: visible } </style> </HEAD> <BODY> <A NAME="anchor429457"></A> <TABLE WIDTH="740" HEIGHT="45" BORDER="0" CELLSPACING="2" CELLPADDING="2"> <TR> <TD><IMG SRC="newLHXicon.gif"> &nbsp;&nbsp; &nbsp;&nbsp; </TD> <TD><FONT FACE = "Lucida Grande" COLOR="#000000" SIZE=+2> &nbsp;&nbsp; &nbsp;&nbsp; SPECIAL menu</FONT> <BR><FONT FACE = "Lucida Grande" SIZE =+0"> <ul id="nav" class="drop"> <li><a href="LHFileMenu.html">File</a> <UL> <li><a href="LabHelpMenu.html">'LabHelper' menu</a></li> </ul> <li><a href="EditMenu.html">Edit</a> <li><a href="ViewMenu.html">View</a></li> <li><a href="A-DMenu.html">A-D</a></li> <li><a href="D-AMenu.html">D-A</a></li> <li><a href="LHSpecialMenu.html">Special</a> <UL> <LI><A HREF="#anchor1160829">Simple math</A></li> <LI><A HREF="#anchor1160830">Simple regression</A></li> <LI><A HREF="#anchor1160831">Expression evaluator</A></li> <LI><A HREF="#anchor1161968">STP adjustment</A></li> <LI><A HREF="#anchor1164750">Altitude &amp; pressure</A></li> <LI><A HREF="#anchor26729">&nbsp;&nbsp;&nbsp;&nbsp;Altitude simulation</A></li> <LI><A HREF="#anchor67097">pO2 estimation</A></li> <LI><A HREF="#anchor1151857">Dissolved oxygen</A></li> <LI><A HREF="#anchor1163195">Metabolic allometry</A></li> <LI><A HREF="#anchor1163195">&nbsp;&nbsp;&nbsp;&nbsp;Minimum flowrate</A></li> <LI><A HREF="#anchor955313">Chamber washout</A></li> <LI><A HREF="#anchor999312">Q10 adjustment</A></li> <LI><A HREF="#anchor1151858">Closed-system respirometry</A></li> <LI><A HREF="#anchor1151859">Day of the year</A></li> <LI><A HREF="#anchor1151859">Sunrise, sunset</A></li> <LI><A HREF="#anchor1151860">Unit conversions</A></li> </UL> </ul></ul> </ul> <ul id="nav" class="drop"> <li><a href="LabHelperTopics.html">using LabHelper</a></li> </ul> </TABLE> <TABLE WIDTH="540" BORDER="0" CELLSPACING="2" CELLPADDING="4"> <TR><TD> <hr> <FONT FACE ="Lucida Grande, Arial, sans-serif"> <P>The <B><FONT SIZE=+1>'Special' menu</FONT></B> contains several utility functions, calculators, and converters.<A NAME="anchor1160829"></A></P> <IMG SRC="LHXimages/math.jpg" align = "right"><P><LI> &nbsp;&nbsp;<B><FONT COLOR="#000000" SIZE=+1>SIMPLE MATH calculator</FONT></B><FONT COLOR="#000000" SIZE=+1> </FONT>This is a basic calculator with some additional keys that are specific to data acquisition.&nbsp; Along with standard math operations, it contains keys for time unit or rate conversions (multiplying and dividing by factors of 60 and 24), pressure (760, 101.325, etc.), Kelvin temperature, and a number of surface and volume conversions frequently used by physiologists and other scientists. &nbsp; <P> The calculator has an RPN function with addition, subtraction, multiplication, and division (which should be familiar to users of HP desk calculators). &nbsp; Note that you should use the <B>underline</b> key (_) instead of the minus key (-) for subtraction (this is because the minus key is assumed to indicate a negative number, not subtraction).<P> Also note that when computing sines, cosines, or tangents, the calculator expects angles in <B>degrees</b> (not radians). <A NAME="anchor1160830"></A> <TR><TD><LI> &nbsp;&nbsp;<B><FONT FACE ="Lucida Grande" COLOR="#000000" SIZE=+1>SIMPLE REGRESSION calculator</FONT></B><FONT COLOR="#000000" SIZE=+1> </FONT><FONT FACE ="Lucida Grande">This window lets you perform simple linear or 2-order polynomial regressions. &nbsp; It is <U>not</U> intended to replace the much more sophisticated regression algorithms found in dedicated statistics packages: &nbsp; it doesn't provide a lot of the standard regression statistics, and there is an upper limit of 20 X-Y variable pairs (you need to enter at least three). &nbsp; Once the data are entered, clicking the <B>'Calculate Regression'</b> button computes and displays the regression coefficients and shows a plot of the data and regression line: </P> <BLOCKQUOTE> <P><IMG SRC="LHXimages/SimpleRegression.jpg" ALIGN="BOTTOM" NATURALSIZEFLAG="3"></P> </BLOCKQUOTE> <ul> <LI>Once a regression has been computed, you can use the <B>'Predict Y from X'</b> and <B>'Predict X from Y'</b> buttons to interpolate values (but note that predicting X from Y does not always work in polynomial regressions).<P> <LI>The X and Y values will be remembered if you close this window and subsequently re-open it (but are lost when you quit <B>LabAnalyst</b>).<P> <A NAME="anchor1160831"></A> <TR><TD><LI> &nbsp;&nbsp;<B><FONT FACE ="Lucida Grande" COLOR="#000000" SIZE=+1>EXPRESSION EVALUATOR</FONT></B><FONT COLOR="#000000" SIZE=+1> </FONT><FONT FACE ="Lucida Grande"> <img src = "LHXimages/ExpressionEval.jpg" align = "right">This routine lets you write a mathematical expression, enter numeric values for the expression variables, and have the computer solve it. The program parses the expression into components and performs the operations. The<B> </B>expression evaluator understands the following symbols (upper or lower case entries are OK):</P> <UL> <LI><B><FONT COLOR="#FF0000">Simple operators:</FONT> </B>+ - * / ^ ( ) <LI><B><FONT COLOR="#FF0000">Complex operators:</FONT> </B>EXP, LOG or LN, LOG10, SIN, COS, TAN, ATN or ATAN, ABS, INT, SQR (square), SQRT (square root) <LI>Two <B><FONT COLOR="#FF0000">special variables</FONT></B> (i.e., <B>channels</B>) named<B> &quot;</B>X<B>&quot; </B>and<B> &quot;</B>Y<B>&quot;</B>, chosen with push-buttons (see image below) <LI><B><FONT COLOR="#FF0000">PI</FONT></B> (or the equivalent Greek letter) <LI><B><FONT COLOR="#FF0000">Numbers</FONT></B> (such as 5, -3.1889, and 1e-10) <LI>You can add a comment at the end of your expression, delineated with the &quot; ` &quot; character. </UL> <P>Some general considerations:</P> <UL> <LI>The '<B>Check expression</B>' button does a preliminary parsing of the expression and indicates if there are any syntax errors (in the above example, this button has been clicked). <LI>The '<B>Evaluate</B>' button processes the X and Y values according to the expression in the upper left window. Results are shown in the yellow text box at the bottom of the window. If any errors are found (see below), a warming message is shown. </UL> <BLOCKQUOTE> <P><B><FONT COLOR="#FF0000">NOTE: </FONT></B>This routine will only 'catch' errors in the basic numeric expression. <B><I>It <FONT COLOR="#FF0000">may not </FONT>detect invalid or meaningless math operations that may be attempted when data are processed,</I> </B>such as division by zero, or taking the log or a non-integer exponent of a negative number. If such situations occur, results may be unpredictable. The algorithm does find most such errors during processing, however.<A NAME="anchor147646"></A></P> <P><TABLE WIDTH="640" HEIGHT="74" BORDER="1" CELLSPACING="0" CELLPADDING= "5"> <TR> <TD BGCOLOR="#ffffff" WIDTH="100%" HEIGHT="54"><I>The underlying code for the <B>expression evaluator </B>was developed by the late, great <B><FONT COLOR="#FF0000">Robert Purves</FONT></B> (recently deceased and greatly missed). &nbsp;I 'borrowed' it -- with his permission -- and made some modifications for <B>LabHelper</B>. &nbsp;But Robert P. deserves all the credit.</i></TD></TR> </TABLE> </P> </BLOCKQUOTE> <TR><TD><IMG SRC="LHXimages/STP.gif" ALIGN="right"><A NAME="anchor1161968"></A> <FONT FACE ="Lucida Grande, Arial, sans-serif"><LI><B>&nbsp;&nbsp; </B>The <B><FONT COLOR="#000000" SIZE=+1>STP ADJUSTMENT </FONT></B>calculator lets you correct for the effects of temperature and pressure on measured flow rates.&nbsp; 'STP' means <U>Standard Temperature and Pressure</u>; by convention this is 760 torr (sea level atmospheric pressure) and 0 degrees C. &nbsp; The calculator functions for both continuous flow measurement devices and volume measurements (i.e., volume by time), and can account for differential internal pressure in the measurement device.</P> <a href="#anchor429457">Top of page</a></li> <TR><TD><A NAME="anchor1164750"></A><IMG SRC="LHXimages/altitude.gif" ALIGN="right"> <FONT FACE ="Lucida Grande, Arial, sans-serif"><LI>&nbsp;&nbsp;<B> <FONT COLOR="#000000" SIZE=+1>ALTITUDE &amp; PRESSURE</FONT>...&nbsp; </B>&nbsp;&nbsp;&nbsp;Computes the relationship between pressure and altitude, based on standard meteorological data (Smithsonian Meteorological Tables).&nbsp; This does not adjust for any effects of weather on local pressure.<P> Note that due to rounding errors, the calculations are not 100% reversible (e.g. computing the pressure at a given altitude and then using that computed pressure to calculate altitude will not yield the identical initial altitude -- but it will be very close). <P ALIGN=CENTER><A NAME="anchor67097"></A></P> <A NAME="anchor26729"></A> </UL> <A NAME="anchor26729"></A> <TR><TD><FONT FACE ="Lucida Grande, Arial, sans-serif"><LI> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B><FONT SIZE=+1>ALTITUDE SIMULATION...</FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This calculator will compute the appropriate gas concentration to simulate one altitude at the barometric pressure of another altitude.&nbsp; For example, you might want to use a custom mixture of oxygen and nitrogen in a lab at sea level to simulate the partial pressure of oxygen at high altitude (say, 4000 meters).&nbsp; Oxygen is the most likely gas of interest but the calculator will also work with other gases.<p> &nbsp;&nbsp;&nbsp;&nbsp;<IMG SRC="LHXimages/AltitudeSimulation.jpg"><P> <a href="#anchor429457">Top of page</a></li> <P><IMG SRC="LHXimages/PO2calc.gif" align = "right"><li> &nbsp;&nbsp;<B><FONT SIZE=+1>pO2 ESTIMATION...</FONT> </B>You can use this calculator to determine the partial pressure of oxygen (pO<SUB>2<FONT SIZE=-1></sub></FONT>) -- or any other gas species in a mixture -- from ambient temperature, ambient pressure (in the gas phase), fractional concentration of the gas species of interest in a <B><I>dry</I></B> gas mix, and the percent saturation of water vapor (i.e., relative humidity) in the gas phase. Oxygen (or other gases) are diluted by water vapor, and the degree of that dilution depends on RH and temperature.</P> <P>In the example at right, pressure is sea level standard atmospheric pressure(760 torr), temperature is the typical mammalian body temperature (37 &deg;C), etc. Note that at this temperature the saturation vapor pressure of water is about 47.6 torr (this is not affected by the total pressure in the system).</P> <P>Other considerations for this calculator:</P> <UL> <LI>The calculated pO<SUB>2<FONT SIZE=-1></sub></FONT> value is applicable for the gas phase, and also for dissolved oxygen, as long as the solution is fully saturated with O<SUB>2<FONT SIZE=-1></sub></FONT>.&nbsp; <LI>The default pressure (torr or kilopascals, kPa) is obtained from the current data file; the default temperature is 37 &deg;C, and the default fractional gas concentration is .2095 (20.95%, the normal oxygen content of dry atmospheric air).&nbsp; </UL> <A NAME="anchor1151857"> <P><IMG SRC="LHXimages/DissolvedOxygen.jpg" ALIGN="RIGHT"><li> &nbsp;&nbsp;<B><FONT SIZE=+1>DISSOLVED OXYGEN...</FONT> </B>This calculator determines the amount of oxygen dissolved in a given volume water, as a function of partial pressure, temperature, and salinity (dissolved solutes). </P> <P>In the example at right, pressure is sea level standard atmospheric pressure (760 torr), temperature 10 &deg;C, the water is fully saturated with oxygen, and there are 2 parts/thousand of dissolved solutes (reasonable for fairly fresh water). The calculator provides the dissolved oxygen per unit volume, and for the total volume.</P> <P><a href="#anchor429457">Top of page</a> <P><A NAME="anchor1163195"></A><LI> <font SIZE=+1><B>METABOLIC ALLOMETRY...</FONT> &nbsp;&nbsp;&nbsp;'m'&nbsp;&nbsp;&nbsp;</B>Use this somewhat specialized utility to make estimates of an animal's resting metabolism, based on its size and taxonomic affiliation.&nbsp; The metabolism calculator has many potential uses; for example, you might want to use it as a 'reality check' if you think your own metabolic data are unexpectedly high or low. <BR> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; The initial popup menu contains some very generalized equations, and also allows you to switch to <B><FONT COLOR="#FF0000">submenus</FONT></B> for specific taxa (arthropods, fish, birds, mammals, etc.).&nbsp; For most taxa, several different equations are available (from different literature sources, which are described in the 'help' field to the right).&nbsp; You can also pick the desired output units.&nbsp; The energy equivalence of metabolism (joules per ml of oxygen consumed) is set at 20.1 joules/ml (this varies -- but not by very much -- with different metabolic fuels).&nbsp; The mass coefficient in the allometric equation ('a' value) is adjusted to reflect whatever output unit is in use.&nbsp; Results can be stored for later use.</P> <IMG SRC="LHXimages/MetabolicAllometry.gif" align = "right"> Metabolism for all taxa are calculated from power functions:<P> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <B> metabolism = a M<sup>b</sup></b><P> (where a is the mass coefficient, M is mass, and b is the mass exponent)<P> <P>This example shows an estimate of the resting metabolic rate (RMR) of a 37.3 g bird, in units of ml O<FONT SIZE=-1><SUB>2</SUB></FONT>/min.&nbsp; The equation was derived from a paper published by Andrew Mckechnie and Blair Wolf (Click <A HREF="MRreferencelist.html">here</a> for a list of the references from which allometric equations were obtained.).<BR> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Note that the mass coefficient ('a' value) and mass exponent are shown and can be edited, and that mass can be in either grams or kilograms.&nbsp; Also, it is possible to make corrections for the effect of body temperature by making the appropriate adjustments to the value of T<FONT SIZE=-1><sub>b</sub></FONT> and Q<FONT SIZE=-1>10</FONT> (in this example, the 'base' T<FONT SIZE=-1><sub>b</sub></FONT>, from which the equation was derived, is equal to the current T<FONT SIZE=-1><sub>b</sub></FONT> so no temperature correction occurs).&nbsp; After changing values in the edit fields, click the <B>'Compute'</b> button to display the new results.<P> <P><LI>&nbsp;&nbsp; <B><FONT SIZE=+1>MINIMUM FLOWRATE...</FONT> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</B>This is similar to the <b>Metabolic allometry</b> calculator, but it also makes an estimate of the flow rate necessary to maintain an acceptable oxygen concentration within a metabolism chamber.&nbsp; This example shows a calculation for a small shark in brackish water (since the osmolarity of water affects its oxygen capacity). &nbsp; Note that the osmolarity popup appears only for fish metabolism. &nbsp; Also keep in mind that the calculation is based on a user-entered maximum <B>change</b> in gas concentration or percent saturation, not on the absolute concentration or partial pressure of oxygen.<p> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<IMG SRC="LHXimages/minimumFlowrate.jpg"></P> You can also adjust the <b>activity intensity</b> for the animal, ranging from inactive (minimal metabolism; MMR) to average daily metabolism (3 X MMR)to very vigorous activity -- up to 100X MMR, which is reasonable for some large flying insects.&nbsp; <P><A NAME="anchor955313"></A></P> <IMG SRC="LHXimages/washoutWindow.jpg" ALIGN="right"> <P><LI> &nbsp;&nbsp;<B><FONT SIZE=+1>CHAMBER WASHOUT& </FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;All metabolic chambers act as 'mixing boxes' for respiratory gases and the incurrent flow of respiratory fluid (gas or water). &nbsp;Unless flow rates are extremely high relative to chamber volume (in which case it may be difficult to attain a sufficent change in respiratory gas concentrations to measure accurately), the excurrent gas concentrations are integrated averages of the 'instantaneous' metabolic rate of the animal over time. &nbsp; This is mostly irrelevant if metabolic rate is constant and you have plenty of time between baseline reference readings, but instantaneous changes (or reference readings) in metabolism produce exponential approaches to the new value, not a step change. &nbsp; The washout kinetics of the chamber are crucial (along with how well a chamber is mixed) in determining the response time to changes in metabolic rates. <P> This window calculates the washout rates of theoretical perfectly-mixed chambers as a function of volume and flow rate. &nbsp; The computed value is the time for X% of intial gas volume to be replaced -- akin to the 'half-life' concept for radioactive decay and related phenomena.&nbsp; Note that no <B>real</b> chamber will exactly match these estimates. <P><A NAME="anchor999312"></A></P> <P><IMG SRC="LHXimages/Q10window.jpg" ALIGN="right"><LI> &nbsp;&nbsp;<B><FONT SIZE=+1>Q10 ADJUSTMENT& </FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This calculates the effect of temperature (Q10) on the rate of reactions or functions -- speed, power, metabolism, etc. &nbsp; Q10 is the factorial change in rate across a 10 C temperature change. &nbsp; To do that, enter a base temperature and an adjusted temperature, the base value of the rate function, and the Q10 (the default is 2.2), and click the '<B>compute adjusted value</B>' button. &nbsp; Alternately, enter the base and adjusted temperatures and the base and adjusted rate values, and compute Q10 by clicking the '<B>compute Q10</B>. button. &nbsp; The temperature difference (base temperature to adjusted temperature) can be positive or negative. </P> <P><a href="#anchor429457">Top of page</a> <A NAME="anchor1151858"> <P><li>&nbsp;&nbsp; <B><FONT SIZE=+1>CLOSED SYSTEM RESPIROMETRY...</FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This calculator computes rates of oxygen consumption (VO<SUB>2<FONT SIZE=-1></sub></FONT>) and/or carbon dioxide production (VCO<SUB>2<FONT SIZE=-1></sub></FONT>) in air or other breathable gas mixture in a closed system (i.e, the animal is sealed in an air-tight chamber for some time and metabolism is computed by the change in concentration of O<SUB>2<FONT SIZE=-1></sub></FONT> and CO<SUB>2<FONT SIZE=-1></sub></FONT> between initial and final gas samples). You need to enter:<br> <img src = "LHXimages/closedSystem.jpg" align = "right"> <UL> <LI> chamber temperature, pressure, and relative humidity (when sealed, not at the end of measurements). <LI> chamber volume <LI> elapsed time (between taking the initial and final gas samples) <LI> initial fractional concentrations of O<SUB>2<FONT SIZE=-1></sub></FONT> (FiO<SUB>2<FONT SIZE=-1></sub></FONT>) and CO<SUB>2<FONT SIZE=-1></sub></FONT> (FiCO<SUB>2<FONT SIZE=-1></sub></FONT>) <LI> the change in concentration (in percent) of oxygen and/or CO<SUB>2<FONT SIZE=-1></sub></FONT>, and the respiratory quotient (RQ) </ul> If you measure only one of these two gas species, the program will use RQ to estimate the other. If you measure both O<SUB>2<FONT SIZE=-1></sub></FONT> and CO<SUB>2<FONT SIZE=-1></sub></FONT> concentration changes, the program will optionally use O<SUB>2<FONT SIZE=-1></sub></FONT> in the calculation of VCO<SUB>2<FONT SIZE=-1></sub></FONT>. NOTE: it is assumed that sample gas is dried before measurement, and the default settings are: <UL> <LI> Initial O<SUB>2<FONT SIZE=-1></sub></FONT> concentration (FiO<SUB>2<FONT SIZE=-1></sub></FONT>) = .2095 <LI> Initial CO<SUB>2<FONT SIZE=-1></sub></FONT> concentration (FiCO<SUB>2<FONT SIZE=-1></sub></FONT>) = .0004 <LI> CO<SUB>2<FONT SIZE=-1></sub></FONT> is absorbed prior to O<SUB>2<FONT SIZE=-1></sub></FONT> measurement <LI> VCO<SUB>2<FONT SIZE=-1></sub></FONT> is computed from VO<SUB>2<FONT SIZE=-1></sub></FONT>, if oxygen is measured, or from RQ otherwise </ul> <hr size="2" width="75%"> <b>Equations notes:</b> <UL> <LI> STP = standard temperature and pressure (0&deg;C, 760 torr) <LI> &Delta;[O<SUB>2<FONT SIZE=-1></sub></FONT>] = fractional change in O2 concentration <LI> &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>] = fractional change in CO2 concentration <LI> FeO<SUB>2<FONT SIZE=-1></sub></FONT> = FiO<SUB>2<FONT SIZE=-1></sub></FONT> - &Delta;[O<SUB>2<FONT SIZE=-1></sub></FONT>] <LI> FeCO<SUB>2<FONT SIZE=-1></sub></FONT> = FiCO<SUB>2<FONT SIZE=-1></sub></FONT> + &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>] </ul> <b>VO<SUB>2<FONT SIZE=-1></sub></FONT> equations: </b> <UL> <LI> CO<SUB>2<FONT SIZE=-1></sub></FONT> is absorbed: VO<SUB>2<FONT SIZE=-1></sub></FONT> = STP volume * &Delta;[O<SUB>2<FONT SIZE=-1></sub></FONT>] /(1 - FeO<SUB>2<FONT SIZE=-1></sub></FONT>) <LI> CO<SUB>2<FONT SIZE=-1></sub></FONT> NOT absorbed, compute from &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>]: VO<SUB>2<FONT SIZE=-1></sub></FONT> = STP volume * (&Delta;[O<SUB>2<FONT SIZE=-1></sub></FONT>] - (FeO<SUB>2<FONT SIZE=-1></sub></FONT> * &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>])/(1 - FeO<SUB>2<FONT SIZE=-1></sub></FONT>) <LI> CO<SUB>2<FONT SIZE=-1></sub></FONT> NOT absorbed, compute from RQ: VO2 = STP volume * (&Delta;[O<SUB>2<FONT SIZE=-1></sub></FONT>] /(1 - FeO2 * (1-RQ)) </ul> <b>VCO<SUB>2<FONT SIZE=-1></sub></FONT> equations: </b> NOTE: at typical &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>], different equations have little effect on calculated VCO<SUB>2<FONT SIZE=-1></sub></FONT> <ul> <LI> from RQ: VCO<SUB>2<FONT SIZE=-1></sub></FONT> = STP volume * &Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>]/(1 - FeCO<SUB>2<FONT SIZE=-1></sub></FONT> * (1-(1/RQ))) <LI> from VO<SUB>2<FONT SIZE=-1></sub></FONT>: VCO<SUB>2<FONT SIZE=-1></sub></FONT> = STP volume * (&Delta;[CO<SUB>2<FONT SIZE=-1></sub></FONT>] - (FeCO<SUB>2<FONT SIZE=-1></sub></FONT> * VO<SUB>2<FONT SIZE=-1></sub></FONT>))/(1 - FeCO<SUB>2<FONT SIZE=-1></sub></FONT>) </ul> <A NAME="anchor1151859"> <a href="#anchor429457">Top of page</a> <P><li>&nbsp;&nbsp; <B><FONT SIZE=+1>DAY OF THE YEAR...</FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This simple calculator will provide the Julian date (days since December 31) for a combination of date, month, and year. &nbsp; It should account for leap years. <A NAME="anchor121846"></A></P <A NAME="anchor1051809"> <P><li>&nbsp;&nbsp; <B><FONT SIZE=+1>SUNRISE, SUNSET...</FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This utility uses the well-known <A HREF="http://en.wikipedia.org/wiki/Sunrise_equation">  Sunrise equation </a> to compute the approximate times of sunrise and sunset from date (month, day, year) and location (degrees latitude and longitude). &nbsp; You need to select North or South latitude, and East or West longitude relative to the Prime Meridian. <BR> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; NOTE: The program expects latitude and longitude in <B>fractional degrees</b>, not degrees and minutes. Thus 27 30 north should be entered as  27.5 (i.e., halfway between 27 N and 28 N). <P> Sun time estimates are approximate for several reasons:<P> <BLOCKQUOTE> " &nbsp; Sunrise and sunset times are based on <B><U>local solar noon</B></U> (i.e., when the sun is at its zenith (highest above the horizon) from the perspective of the observer s position. &nbsp; This is likely to be slightly different from local time. &nbsp; As defined by people, time zones are arbitrary, and since they are roughly 15 of longitude wide and often do not run strictly north and south, sunrise and sunset times can vary by an hour or more with a single time zone.<P> " &nbsp; The calculator has no allowance for elevation above sea level (which makes rise times earlier and set times later, if the horizon is at sea level). &nbsp; It also has no allowance for local topography  for example, if the observer is in a deep valley, the visual horizon is elevated above the  real horizon, and rise times will be later and set times will be earlier than shown here.<P> " &nbsp; The precise times of sunrise and sunset are of concern to astronomers and the like, but for most purposes they are rather  fuzzy due to the angular diameter of the solar disc (about 32 minutes of arc or 0.53 degrees), atmospheric refraction, etc.<P> </BLOCKQUOTE> NOTE: The U.S. Naval Observatory hosts a web page (<A HREF = "http://aa.usno.navy.mil/data/docs/RS_OneDay.php">USNO Sun and Moon Data</a>) that permits very accurate calculations of solar and lunar data.&nbsp; It incorporates  fixes for many of the issues described above, and  if you are connected to the internet  can be accessed with the <B> Naval Observatory Website </b> button.<P> <IMG SRC = "LHXimages/WorldMapImage.jpg" align = right> " The <B>'Get Latitude and Longitude From World Map'</b> button opens a window with a world map (d'oh!) in Mercator projection. &nbsp; Move the cursor to the desired location and hit either the <B>spacebar</b> or <B>return</b> keys to select that position; as you move the cursor the latitude and longitude boxes at upper left update continuously. &nbsp; If you want to select a position on a higher-resolution 'regional' map, click the <B>Zoom in X5</b> button, a rectangular cursor appears; move it until it encloses your area of interest and hit either the <B>spacebar</b> or <B>return</b> keys to enlarge that region. &nbsp; Then use the cursor and keys to select a position as described above. <P> <IMG SRC = "LHXimages/AustraliaMapImage.jpg" align = right>Location data are accurate only to 0.33 degree of longitude and 0.25 degree of latitude on the world map and 0.11 degrees of longitude and latitude on the regional maps, but that should be accurate enough for most sunrise-sunset calculations. <P> As geographic references, the maps show the equator (yellow), the Prime or Greenwich Meridian (zero degrees of longitude), the Arctic and Antarctic Circles (~ 66.5 degrees N and S), and the Tropics of Cancer and Capricorn (~ 23.3 degrees N and S). Only a few of these will be visible on the enlarged regional maps. <P> Of course, if you want higher-resolution position data (and you are connected to the Internet), use <A HREF="http://www.google.com/earth/">Google Earth</a>.<P> " The <B>'Annual Plot'</b> button will compute and display an entire year's day length cycle, based on latitude-longitude position. &nbsp; The <B>'Print Data to Spreadsheet'</b> button makes a tab-delineated .xls spreadsheet containing the annual cycle (date, sunrise time, sunset time, and day length). &nbsp; This example shows a Polar-region cycle, with complete darkness in winter and 24-hour sunlight in summer:<br> <center> <IMG SRC="LHXimages/suncycle2.jpg"" > </center> <A NAME="anchor1151860"> <P> <li>&nbsp;&nbsp; <B><FONT SIZE=+1>UNIT CONVERSIONS...</FONT> </B>&nbsp;&nbsp;&nbsp;&nbsp;This calculator will convert many commonly-used units into other units. The conversions are arranged by type, selected with the radio buttons on the right of the window. This utility will also estimate certain biophysical and meteorological data. In the example below, solar radiation intensity is estimated as a function of how far the sun is above the horizon. <p> <center> <IMG SRC="LHXimages/UnitConversions.jpg" align = "center"> </center> <A NAME="anchor121846"> <HR ALIGN=LEFT> <table width = "740" Border = "0"> <tr><td>go to: <td> <FONT FACE = "Arial"> <ul id="nav" class="drop"> <li><a href="#anchor429457">Top of page</a></li> <li><a href="LabHelperTopics.html">LabHelper topics</a></li> <li><a href="http://warthog.ucr.edu/">Warthog Systems home</a></li> <li><a href="mailto:chappell@ucr.edu?subject=Warthog%20LabHelper%20question">email</a></li> </ul> </table> </BODY> </HTML>