Monday, July 30, 2012

HBD is not-nice.

Taking my cue from John Derbyshire, I've been having "the talk" with my daughters. I believe explaining to them the provenance of their immediate experience and the features of the larger reality to be both right and necessary.

But, honestly, I feel kinda dirty.

Regarding this Newsweek article on racial attitudes in children (via Discriminations and at least one other blog that I can't remember at the moment):

[UT professor Rebecca Bigler's] reasoning is that kids are developmentally prone to in-group favoritism; they’re going to form these preferences on their own. Children naturally try to categorize everything, and the attribute they rely on is that which is the most clearly visible.
We might imagine we’re creating color-blind environments for children, but differences in skin color or hair or weight are like differences in gender—they’re plainly visible. Even if no teacher or parent mentions race, kids will use skin color on their own, the same way they use T-shirt colors. Bigler contends that children extend their shared appearances much further — believing that those who look similar to them enjoy the same things they do. Anything a child doesn’t like thus belongs to those who look the least similar to him.

My experience with my older daughter causes me to doubt this assessment. In the city we used to live in, Γ1 attended kindergarten and 1st grade part-time classes as part of the "homeschool program" of a public charter school. I liked the program in general, but it was here where she was presumably exposed to the diversity dogma.

It took me years to de-program this nonsense. Every evening, I would give Γ1 an opportunity to tell me "what she learned in homeschool", with particular interest in the history and science lessons. Typically, I used these lessons as a springboard to discuss HBD/race-realism. Now that she's older and more perceptive, however, I've been more forthright about putting all the cards on the table. Γ1 used to tell me how "everybody is equal", but the message seems to have gotten through. (Although she probably still thinks her Dad is a bit of a crank, which is fair enough, I guess.)

I think the diversity dogma is intrinsically appealing to children, or at least children living comfortable middle-class suburban lives. "Equality" is "nice"; realism about the world and its dangers is "not nice". And who wants to be not-nice?

OTOH, maybe Γ1 is exceptional in this regard. Before Φ could afford all-white neighborhoods, Γ1 was exposed to somewhat more playmate diversity than, say, her younger sister. And never, to my recollection, did I detect the least bit of reticence in playing with children of other races. She really was colorblind. Not in the literal sense -- she knew children had different color -- but she never invested the kind of meaning in that difference that Bigler predicts.

Younger sister, in contrast, hasn't had occasion to play with minority children. The only time she has seen them is during Halloween when the more "urban" children descend on Φ's lily-white little burg. While not expressing anything specific, I can tell that she gets very . . . reserved is the way I would put it. But Γ2 is also attending 2nd grade in public school, and I think my discussions with Γ1 make her . . . uncomfortable. After all, who wants to be not-nice?

Friday, July 27, 2012

Who make the best teachers?

Laura McKenna, guest posting for Megan, writes:

The bad news is that a growing number of faculty at state or public colleges are adjunct instructors. Adjuncts are temporary faculty members who teach classes for low pay, no benefits. They do not have the protections of tenure. They are often not unionized. 1 million of the 1.5 million people teaching in American colleges are adjuncts. The number of adjunct faculty has increased dramatically over time. LinkedIn reports that it is the fastest growing job description.

Doing some back of the envelope computations using data from the Chronicle of Higher Education, I found some depressing news about my alma mater and other public colleges. At SUNY Binghamton, of the 812 faculty, 383 are adjuncts. That's 47 percent of their total faculty. At Penn State, of their 3,187 full time faculty, 1,428 are not tenured or on tenure track positions. In other words, 49 percent of their faculty do not have job security, equal pay, or benefits. If you attend University of Tennessee at Knoxville, you are highly likely to be taught by a graduate assistant. Of, their 4,235 teachers, only 1,295 are tenured or tenure-track professor. 2,062 of their teachers are graduate assistants.

In a report released last year, 56 percent of all classes at community colleges in Pennsylvania were taught by adjunct or non-tenure track professors. They receive $2,500 per class. If the adjuncts taught a staggering five classes per semester, their salary would be $25,000 per year. They often receive no benefits.

All these adjuncts are bad news for undergraduates at the public colleges. Many adjuncts are excellent teachers, but their temporary status and their exclusion from faculty meetings means that students can't rely on them for advice on course selection. It's difficult to develop relationships with faculty that may not have their own offices or might teach at multiple schools. It's also hard to be an excellent professor when you're poor and your career is unstable.

There are several overlapping themes here.  One is the age-old conflict of interest between undergraduate and graduate student priorities.

The undergraduate experience is 90% platform instruction, and thus the kind of instructor they want is one with the ability to be engaging, to be sufficiently interested in the fundamentals to have a firm idea of how they are best apprehended.

The graduate experience, especially at the Ph.D. level, is mostly research.  Their most significant faculty interaction will be with their advisor, and secondarily with their other committee members.  What they want, first, is someone capable of directing them towards and managing them through a properly scaled, feasible, and dissertation-worthy research topic.  Second, they want money.  Which preferably means sponsorship for the research, and if not that, then a teaching assistantship.

The skill sets involved are only accidentally related.  A professor skilled at managing a productive (and well-funded) research program does not for that reason have any ability at delivering a disciplined lecture; a good and enthusiastic lecturer of the basics only developed that ability because he wasn’t interested managing research.

The institutional incentives are even worse.  With a few exceptions (Rose-Hulman, the Service Academies), most public universities reward successful research programs, not teaching.  While at some schools it is theoretically possible to win tenure on the strength of academic instruction (which usually includes higher-order activities like course development and textbook writing), in practice most tenure-track faculty don’t take this route.  So little effort is put into teaching.  And the need to get money to their graduate students often puts those grad students in front of undergraduate classrooms.

I experienced these conflicts from both sides.  As an undergraduate, I suffered hatefully through any number of professors, famous for their research programs, droning indifferently in barely intelligible English at the head of 200-seat lecture halls.  As a graduate student, those same professors (figuratively speaking) became vital to my research success.

What to do?

I think the Armed Services get the solution exactly right:  separate institutions – e.g. USAFA and AFIT – separate budgets, separate faculty.  Thus, no opportunity to treat undergraduates like cannon-fodder for the research programs.

Alternatively, one school I knew specifically created something of a career track for lecturers, and paid them salaries a lot higher than the adjunct numbers quoted above, though not as high as professors whose research programs brought money directly to the university.

But I want to push back against McKenna’s suggestion that the solution is to put more tenured faculty in front of undergraduates.  In my experience, these professors were not obviously better, and sometimes a lot worse, than a TA or adjunct.

I also submit that the poor pay for adjunct lecturers probably reflects the supply and demand.  Last year, I myself applied for a handful of those poorly-paid adjunct positions on the strength of a Ph.D. and prior college instruction experience.  I was unsuccessful, so I can only assume that the successful candidate was more qualified than me.  Which made them pretty qualified, if you don’t mind me saying.  So, yeah, more money for lecturers would be nice, but I can hardly blame the schools if they can get qualified people to do the work for less.

Thursday, July 26, 2012

Radiometric Error Evaluation, Part V: Results

In the last post, I promised to evaluate the integral:

eqn10_thumb[4]

This is only partially true.  I have no idea how to solve an equation like this analytically, although I know the correct answer.  What I can do, however, is solve it numerically, setting our constant radiance = 1000, the radius of our emitting sphere = 1:

function [R,E]=intE()
    L = 1000;
    re = 1; 
    l1 = 0; % Sensor nadir
    figure;
    for i = 1:200,
        R = 10.^(-1+.02*i);
        l2 = acos(re./(R + re)); % Limit of field of view;
        E(i) = quad(@irradiance,l1,l2);
    end;
    function E = irradiance(phi)
        Rprime = sqrt((R + re)^2 + re^2 - 2*(R+re)*(re).*cos(phi));
        gamma = asin(((R + re)./Rprime).*sin(phi));
        theta = asin((re./Rprime).*sin(phi));
       
        E = (2*pi*L*re^2./Rprime.^2.*sin(phi).*cos(gamma).*cos(theta));
    end
end

I graphed the value of E vs. R, along with the value of our estimate from two lessons ago:

Result0

The estimate appears to be pretty good for R >> reBut before I graph the error, I decided to add to the estimate E = π L re2/R2 the estimate E = π L re2/(R +re)2:

Result1

Well, how about that.  It turns out E = π L re2/(R +re)2: was so good an estimate it completely overwrote the true value across all values of R.

Let’s plot the error.

Result2

By the looks of it, the error of Es2 (taken as an absolute value to graph on a log scale) is pretty much limited to accumulated random rounding errors, although these errors might be getting larger the farther away my receiving aperture is, and the smaller the emitting surface appears.

Basically, this is saying that for purposes of analysis,

Wednesday, July 25, 2012

Investigating Irradiance Error, Part IV: True E

Let’s imagine a differential emitting area dAs on a spherical emitting surface of radius re at a distance R from a differential receiving surface dARdAs is at distance R’ and aspect angle γ from dAR; dAR is at aspect angle θ to dAs.  Also dAs is at an angle φ from the point of nadir to dAR.  In summary,

Picture1

Applying the Law of Sines gives us:

eqn1

allowing us to solve for both θ and γ in terms of φ:

eqn2

The Law of Cosines gives us:

eqn3

These relationships will be important later.

Radiance is the amount of power emitted into each differential solid angle from each differential area perpendicular to that angle.  For a lambertian surface, it is by definition a constant:

eqn5

In units of steradians, a differential solid angle dΩ measures the ratio between the surface of a sphere subtended by that angle and the square of the sphere’s radius, much in the way an angle in radians measures the ratio of the length of the arc it subtends and the radius of the circle.

We must also bear in mind that the perpendicular area (i.e. the cross-sectional area as it appears from the direction of observation) bears the relationship to the true area shown in the figure below.

Picture2Thus:

eqn6

Substituting into our equation for radiance gives us:

eqn7

The quantity in which we are interested is irradiance E, the power per unit area entering our differential receiving area, dAR.  Solving for this quantity yields:

eqn8

The differential surface area of a sphere, dAs, is the standard calculus formula:

eqn9

where dα integrates around the circle of the visible surface to 2π, and the interior body angle ranges from 0 to the point where  γ is a right angle.  A simple application of the definition of a cosine yields:

eqn4

Substituting in these values gives us our final integral:

eqn10

We will evaluate this integral in our next lesson.

Tuesday, July 24, 2012

Obama didn’t build it, either.

Mr. Obama, having run with apparent impunity the most lawless administration in the history of the presidency, has now got himself in a spot of bother for . . . speaking without a teleprompter:

If you were successful, somebody along the line gave you some help. There was a great teacher somewhere in your life. Somebody helped to create this unbelievable American system that we have that allowed you to thrive. Somebody invested in roads and bridges. If you've got a business. you didn't build that. Somebody else made that happen. The Internet didn't get invented on its own. Government research created the Internet so that all the companies could make money off the Internet. The point is, is that when we succeed, we succeed because of our individual initiative, but also because we do things together.

Obama’s legion of apologists, after flailing about for a bit, have argued that, notwithstanding its grammatical construction, what he intended by the bolded portion was that individual businesses and their creators do not directly build the infrastructure on which they rely to be successful; rather, this is the fruit of collective effort.  This point is, on one reading, trivially true – we aren’t yeoman farmers anymore – but has this really been a contested insight since, I dunno, 1920 maybe? 

Among cultural anthropologists, perhaps not.  But they have very little say in how a people actually mythologizes itself.  America’s dominant economic myth is one of individual achievement, and this mythology has played no small part in our success.  Obama is attempting to inspire a counter myth of collectivism, a mythology that gave us . . . well, Soviet Russia, Red China, etc.

I’m quite comfortable having a national myth that doesn’t quite match the facts on the ground, so long as it pulls its weight in utility.  If Obama was running neck-and-neck with the Libertarian Party, then it could be plausibly argued that “individualism” might have jumped the shark.  But with Romney?  These two are arguing over a couple of inches on collectivism’s 40 yard line*.

But that’s not really what bothers me.  There are two things that bother me.

First, the flip side of the observation that the potential for private wealth – up and down the economic scale – is made greater by public infrastructure is that public infrastructure also doesn’t spring wholly formed from the mind of government bureaucrats:  it relies on some amount of pre-existing private wealth to finance it. whether the “money” representing that wealth is taxed, borrowed (which is deferred taxation), or simply printed (which is a tax of a different sort).  Now, with double-digit unemployment, trillion-dollar deficits, and a debt-to-GDP ratio of around one, it’s pretty apparent that Obama is worrying about the wrong side of this relationship.

The second thing that bothers me goes even deeper:  Obama’s fundamental dishonesty in his framing.  I will happily stipulate that we are none of us as “individual” as we like to think.  Never mind infrastructure:  we did not even “build” the very DNA from which we draw the intelligence and energy to make something of ourselves.  We did not “build” the Anglo-Saxon culture – especially those of us that aren’t Anglo-Saxon – that enables the civic trust and cooperation necessary for enterprise beyond the subsistence level.  We did not “build” the discoveries and inventions on whose shoulders we stood to exercise our own creativity.  We did not fight the wars that expanded and secured our nation’s territory.  We are, in these respects, merely heirs of the hard work and self-discipline of our ancestors.  A well-governed country – Japan, say, or Iceland – respects the heritage it has received and seeks to preserve it.

The irony about Obama is that he has spent his rule actively undermining those very conditions.  Obama’s immigration policies have flooded the nation with illiterate Mexican peasants, driving down wages, driving down civic trust, and eating away at both the physical and cultural capital on which the nation survives.  Obama’s trade policies have flooded the nation with cheap Chinese imports, destroying the high-paying jobs from which taxes can be paid to fund public services.  Obama’s foreign policies have frittered away the nation’s blood and treasure on endless undeclared foreign conflicts inimical to our national interest.  Obama’s crime policies have exposed its historic majority to a rising tide of predatory black (and brown) criminality while plundering our wealth and opportunity for the benefit of minorities.  Obama’s social policies have undermined families and the parental investment that go with them, setting ever greater percentages of the nation morally adrift.  Obama’s government policies have had nothing to do with improving public services, and everything to do with gross redistribution of wealth.

In these, Obama may haves merely expanded the policies of his predecessors – but expand them he did.  Romney’s claim to succeed Obama may be that he only aspires to be marginally less destructive to the common good than Obama – but he will be less destructive.  So I don’t really care about whether this little kerfuffle is some kind of proxy battle over top marginal tax rates or whatever.  The Japanese and Icelanders pay much higher taxes than we do – because their productive enough to afford them and receive high-quality public services in return.  No, what I do care about is that Obama is lying through his teeth when he talks about the common good of the nation.

UPDATE: Chris already said this better.

Monday, July 23, 2012

Investigating Irradiance Error III: Estimated E

In the last two posts, we set out to find the relationship between four radiometric quantities:

  • Exitance (M): the power density emitted by a surface, measured in Watts / m2. We will reserve B for the per-micron un-integrated quantity.
  • Radiance (L): the power density emitted by a surface into each solid angle, measured in Watts / m2 / steradian.
  • Intensity (I): the power emitted by a point source into each solid angle, measured in Watts / steradian.
  • Irradiance (E): the power incident upon a receiving surface, measured in Watts / m2.

We discovered that the relationship between exitance and radiance followed the simple formula for a lambertian surface:  M = πL.  We will now look at the relationship between these and  irradiance.  If anything, properly calculating this last is the most critical; as its name implies, radiometry is about using the power incident on our measuring device to infer the power being emitted from the surface of interest.

    Let us assume that a spherical object of radius Robj is sufficiently far away from our sensor that we can treat it as a point source of intensity I.  The total power Φ it emits is equal to the product of its exitance M and surface area A; its intensity I is that power divided by the total surrounding solid angle, 4π.  Thus:  

    clip_image002

    You will remember that intensity is in units of Watts / steradian.  Thus, if we assume that the sensor is looking directly at the emitting object, we can find the irradiance at the aperture of our receiver by multiplying the intensity by the solid angle Ω subtended by the aperture and dividing by the area Arcvr of the aperture.  Remembering that the definition of solid angle is the ratio of the area of a sphere subtended by that angle divided by the square of the radius gives us:

    clip_image002[4]

    where Rpath is the distance from the emitting object to our sensor.

    Alternatively, we can treat our emitting object as a disk of radius Robj.  It’s radiance L is the exitance M divided by π as found previously.  The irradiance on a sensor at distance  is the product of the radiance, the solid angle Ω subtended by the sensor’s aperture, and the disk area Aobj = πRobj2, divided by the area of the sensor aperture:

    clip_image002[6]

    Thus, we can see that whether we approximate our emitting object of radius Robj as a point source or a disk, we get the same result for the amount of radiation incident on a sensor at distance Rpath.  (The textbook irradiance of, for instance, the sun at the top of the earth’s atmosphere is 1480W/m2, for instance.)

    However, we must point out the obvious:  an emitting sphere is not a disk, and it may not appear as a point source.  For instance, the sun’s dimensions are apparent to an observer on the earth, 93M miles away.

    In our next post, we will calculate the exact irradiance on the aperture of a sensor from a spherical emitting object.

    (Note:  I apologize for the crappy looking equations.  I have a procedure for cleaning them up, but it’s tedious, and I’m tired.)

    Sunday, July 22, 2012

    Hierarchies

    I just received an Amber Alert on my teevee while watching Breaking Bad. I didn't know that Amber Alerts were sent out through the Emergency Broadcast System.

    The alert proceeded as follows (the names have been changed):

    The missing child is named John Smith, a black male [some number of months old, height and weight]. The suspect is also named John Smith, a black male, aged 27, 5'6", 150 lbs . . . .

    So . . . the normal rule that the race of perpetrators (if they're black) should be censored is suspended when the perpetrator has "kidnapped" . . . his own son? I'll have a lot of egg on my face if the child comes to harm, but I couldn't help thinking this was interesting.

    Friday, July 20, 2012

    Anna Breslaw on the Jews

    I’m writing this late Thursday evening, for publication on Friday.  I can’t guarantee that Miss Breslaw will still have a job by then – so far Tablet is standing firm, but these show trials and purges tend to move very fast once they get going.  Already, her prior work for Tablet has been taken down, including the picture of Anna in her Halloween costume:

    AnnaBreslaw

    Yes, that’s Anne Frank.

    Miss Breslaw’s essay, which draws not just on her experience with Holocaust survivors but also from the AMC series Breaking Bad, should be read in its entirety for the full context.  But here is the offending portion (H.T.:  Ace):

    My father’s parents were Holocaust survivors, and in grade school I received the de rigueur exposure to the horror—visiting geriatric men and women with numbers tattooed on their arms, completing assigned reading like The Diary of Anne Frank and Night. But the more information I received, the less sympathy the survivors elicited from me. Each time we clapped for the old Hungarian lady who spoke about Dachau, each time Elie Wiesel threw another anonymous anecdote of betrayal onto a page, I eyed it askance, thinking What did you do that you’re not talking about? I had the gut instinct that these were villains masquerading as victims who, solely by virtue of surviving (very likely by any means necessary), felt that they had earned the right to be heroes, their basic, animal self-interest dressed up with glorified phrases like “triumph of the human spirit.”

    I wondered if anyone had alerted Hitler that in the event that the final solution didn’t pan out, only the handful of Jews who actually fulfilled the stereotype of the Judenscheisse (because every group has a few) would remain to carry on the Jewish race—conniving, indestructible, taking and taking.

    I haven’t ever met any Holocaust survivors.  I have known several Jews, though, and I will say that they had this in common:  a massive chip on their shoulder, specifically an adversarial posture towards gentile American culture.

    Once upon a time, even Hollywood was free to explore Breslaw’s thesis:  that the Holocaust might have left behind people that were pretty damaged.  But now that discussion has become verboten, even as secular Jewish culture has become ever more hostile and predatory.

    Wednesday, July 18, 2012

    Investigating Irradiance Error, Part II: Relationships

    In my last lesson, I defined four radiometric quantities:

    • Exitance (M): the power density emitted by a surface, measured in Watts / m2. We will reserve B for the per-micron un-integrated quantity.
    • Radiance (L): the power density emitted by a surface into each solid angle, measured in Watts / m2 / steradian.
    • Intensity (I): the power emitted by a point source into each solid angle, measured in Watts / steradian.
    • Irradiance (E): the power incident upon a receiving surface, measured in Watts / m2.

    Radiance is the amount of power emitted into each differential solid angle from each differential area perpendicular to that angle. For a lambertian surface, it is by definition a constant:

    eqn5_thumb1

    where Φ is the power in Watts.

    In units of steradians, a differential solid angle dΩ measures the ratio between the surface of a sphere subtended by that angle and the square of the sphere’s radius, much in the way an angle in radians measures the ratio of the length of the arc it subtends and the radius of the circle.  Note that the subtended surface area of a sphere is only an approximation of the subtended area of a flat surface; however, the approximation is good enough at small angles, and exact at differential angles, which is what we are intending here.

    Did you notice the little perpendicular sign after the differential sending area dAs?  This is to remind us that the perpendicular area (i.e. the cross-sectional area as it appears from the direction of observation) bears the relationship to the true area shown in the figure below.

    Picture2_thumb3

    This relationship applies to both the receiving area dAR and the sending area dAs, as shown here:angles

    Using these definitions and basic trigonometry gives us the following relationships:

    angle_eqn

    We now have enough equations to solve for exitance M in terms of radiance L by integrating over the surface of a hemisphere defined by the differential surface area dAR:

    M_integral

    First, we point out that the hemisphere is always facing the center, hence θR =0°, so cosθR =1.  Next, we replace dAR with the area element for integrating over the surface of a sphere in polar coordinates:

    dSurfaceArea

    dα conveniently integrates out to 2π, and the R2’s cancel.  We’re only integrating over a hemisphere, so θs ranges from 0 to π/2.  Thus:

    MeqPiL

    This relationship, M = πL for a lambertian surface, is sufficiently rigorous that Planck’s formula itself is often expressed in terms of radiance rather than exitance.  However, relating these quantities to irradiance and intensity often make use of assumptions which are less than intuitive.  We will examine these assumptions in the next post.

    Tuesday, July 17, 2012

    Democracy vs. the MultiCult

    I remember reading a couple of decades ago, before Hong Kong was absorbed into what I still like to call Red China, that the British had periodically attempted to introduce limited self-government to their protectorate but had always been bullied out of it by the island's future masters. The Reds perceived, probably correctly, that a democratic Hong Kong would have enjoyed an independent legitimacy that would have made its takeover much more problematic than merely replacing the British.

    I thought about that story as I read the Salon article about Midtown Inc., a Community Development Corporation that has apparently taken over many government functions for a gentrifying neighborhood in Detroit. Readers may have remembered that in my last post about Detroit, I wrote that the best thing for the city was to "part it out". I should have added then that the possibility of spinning off the periphery into "charter cities" or independent municipalities was exceptionally remote: there was just no way that the Detroit government would cede its territory voluntarily.

    Midtown Inc., however, seems to have managed to do something like this. I'm not quite sure how to characterize MI's somewhat complicated relationship with Detroit city government. Steve calls it government-by-"Unelected Nice White Lady Rulers"; the phrase that comes to my mind is "Byzantine". But as Steve points out, what it surely is not is democracy.

    The lack of democracy may have been the only path to independence the Detroit government would find sufficiently unthreatening. If this "shadow government" actually had elections, then its gowing de facto seccession would be obvious. As it is, MI only has the role of colonial administrator: a curiosity, perhaps, but Detroit government can console itself that it still holds the "real" power.

    Come to think of it, didn't Byzantium also have to run a diverse empire?

    Monday, July 16, 2012

    Radiometry Calculation Error, Part I: Background

    No discussion of radiometry would be complete without Planck’s equation, which describes the power of the radiation emitted from a surface at a given temperature.  As a function of wavelength λ and temperature T in Kelvin, Planck’s equation is:

    Planck's Formula

    where h is Planck’s constant, kB is Boltzmann’s constant, and c is the speed of light in a vacuum.

    Below is the iconic graph of Planck’s equation in units of Watts per square meter per micron for wavelengths ranging from the UV through the thermal towards the RF, and temperatures ranging from room temperature (300K) to the sun’s surface (6000K).  We note that as the temperature increases, the peak of the curve shifts towards the shorter wavelengths.  For instance, the strength of the sun’s radiation conveniently peaks in the visible wavelengths (roughly 0.4 – 0.7 microns).  While thermal emissions are quite strong (human eyes are sensitive to about 10-3 Watts/m2), they are only strong in the thermal wavelengths (7 – 20 microns), beyond where we can see.

    exitance_vs_wavelength_by_temp

    I should also note that in practice any radiation sensor will collect over a finite bandpass; thus, Planck’s equation must be integrated over whatever wavelengths are under consideration.  In this respect, Planck’s equation is much like a probability density function, which must also be integrated over a range of values to find their probability.

    Of course, knowing the surface exitance alone doesn’t tell us the radiation density reaching a given point, but before we discuss this, we should define some terms:

    • Exitance (M):  the power density emitted by a surface, measured in Watts / m2.  We will reserve B for the per-micron un-integrated quantity.
    • Radiance (L):  the power density emitted by a surface into each solid angle, measured in Watts / m2 / steradian.
    • Intensity (I):  the power emitted by a point source into each solid angle, measured in Watts / steradian.
    • Irradiance (E):  the power incident upon a receiving surface, measured in Watts / m2.

    For those of you without much background in solid geometry, I will discuss solid angles in the next lesson, but for now consider your own experience.  We have little trouble seeing most objects without regard to either the angle of observation or the angle of the incident light.  This is because the object is reflecting most of the light equally in all directions into the surrounding hemisphere.  This kind of reflection is called lambertian.  On the other hand, if you hold the object up to the light, most of the time you can find an angle at which you see a glint or bright spot; this kind of reflection is called specular.  In the case of a mirror, for instance, almost all the incident light is reflected specularly.  An object’s particular mix of lambertian and specular behavior is called its bidirectional reflectance distribution function (BRDF); however, absent this specific knowledge, the lambertian assumption is usually the safest, especially for emitted as opposed to reflected radiation.

    I will discuss the relationship between these quantities in my next lesson.

    Friday, July 13, 2012

    Fat-Only Gyms Mean Higher Prices for Fit People

    From CBS Sacramento:

    New Trend: Gyms Banning Slim Clients To Foster Comfort For Overweight Patrons

    A new fitness trend appears to be sweeping the nation – one that expressly excludes those on the more slender side of the scale.

    Multiple reports have surfaced recently about gyms that cater exclusively to zaftig clients looking to lose weight in a place free of potential judgment from other, smaller patrons.

    Though some all-inclusive gyms have attempted in the past to create a safe haven for anyone interested in exercising – for example, Planet Fitness, a national chain of gyms with a “judgment-free” motto and mentality – some creators of obese-only gyms feel it’s not enough.

    Um . . . yeah, this one isn’t that hard to figure out.  From the perspective of the fitness center’s business model, the ideal client is one who buys an expensive membership . . . and then seldom uses it, allowing the gym to carry a larger membership relative to its capacity.  These fat-people-only gyms are calculating, probably correctly, that such clients are overrepresented among the obese.

    Although my employer has always operated exceptional fitness facilities, this development kind of sucks for people like me who unthinkingly rely on a lazy fitness center subscription base to keep the price down.  What will a gym membership cost when everybody who buys one actually shows up 3+ times a week?

    Thursday, July 12, 2012

    George Zimmerman not a racist . . .

    . . . according to the FBI (H.T.: Steve.)

    I wish Zimmerman well, but what bothers me about this whole line of inquiry is that it is attempting to criminalize a man's personal opinions. Racism, in and of itself, is not a crime.

    Now, "hate crime" laws are, in practice, an anti-white travesty, but they only apply to actions that are already illegal. The USDOJ is attempting to make an issue of Zimmerman's racial views without having proved that his self-defense was illegal. Meanwhile, the state of Florida has accused Zimmerman of "bias". But here again, bias is not a crime; rather, discrimination is a crime in a number of narrow circumstances (e.g. employment). Calling the police about a suspicious person is not one of those circumstances, nor is self-defense. A man set upon by a hopped up thug may choose to use violent force to protect himself . . . or choose not to use violent force. He is free to make that decision based on anything or nothing at all; what matters legally is that he has been set upon.

    Zimmerman, it turns out, seems to be a liberal choirboy, so this particular attack doesn't seem likely to pan out for the howling mob. But it's nonetheless a backdoor way of making criminalizing politically incorrect views on race. Needless to say, I take that kinda personally.

    Wednesday, July 11, 2012

    Nerd Fantasy

    An Alex Goot original, directed by Kurt Schneider:

    Lightning–Alex Goot

    I’m a sucker for this stuff.

    The coffee incident reminded me of the time a girl came up and stood next to me at one of those coffee prep stands with holes in the countertop for trash.  I proceeded to open a sugar packet . . . and pour the contents into the trash.

    This wasn’t a bad opener actually, considering I got a giggle and a question about my caffeine dependency.  But I had no follow-up, mumbling something noncommittal and shuffling away.

    Monday, July 09, 2012

    How is Dominance Resisted?

    Athol Kay writes:

    Most interpersonal conflict arises from attempts to maintain threatened dominance and/or evade being in a submissive position. When I started “breaking free” at work, I got into “trouble” several times with my superiors. Once it became apparent I wasn’t going to be contained, and in fact was becoming someone that could bump back on them rather firmly, they backed off and were much nicer.

    I was thinking about that while watching this scene from Margin Call, a movie with a fair number of high-dominance males.  For those of you who haven’t seen it (and it’s a great movie, btw), it concerns the 2008 decision by “the firm” (i.e., Goldman Sachs) to dump it’s worthless MBS portfolio on unsuspecting investors.  The head of trading Sam Rogers (Kevin Spacey) has objected to this, and Sam’s boss Jared Cohen (Simon Baker) is shown here telling Sam’s subordinate Will Emerson (Paul Bettany) that he may have to take over if Sam doesn’t “step up”.  Watch as Will pushes back:

    Basically, Will is two levels down from Jared in the firm’s hierarchy, yet he effectively resists Jared’s dominance.

    Personally, I don’t really have a problem taking the submissive role with duly-constituted, formal authority.  I do, however, resist dominance by titular peers.

    The problem is . . . I never manage that resistance in socially constructive (for me) ways.  I never arrive at the place where my unwillingness to be dominated gets me better treatment.  What usually happens is that I wind up being a social pariah.

    Friday, July 06, 2012

    Is it betrayal if it was anticipated?

    I hate being right . . .

    NumbersUSA
    Urgent Action

    Congress first time in 2010, promising to stop immigration from hurting jobless Americans -- What a DISAPPOINTMENT these freshman congressmen have been!

    It is not a happy 4th of July for millions of Americans who are greatly restricted in their liberty and pursuit of happiness because this Congress has done nothing to change the immigration status quo, leaving them unemployed and struggling to provide for their families.

    Take a look at the list below. Note the freshman in your state who promised to support changes in nearly every part of our immigration system but has stood by and allowed the government to issue permanent work permits to nearly 2 million more immigrants. Furthermore, these Congressmen have failed to support Judiciary Chairman Lamar Smith in his effort to mandate E-Verify to open up jobs held by more than 7 million illegal aliens.

    Here is the list of Representatives who took the NumbersUSA survey in 2010 and promised to be True Reformers but who have failed to move against mass importation of immigrant labor or to aggressively challenge illegal immigration:
    Florida

    • Southerland, Representative Steve (R-FL-02)
    • . . . .

    My regular readers may remember that, in a couple of posts two years ago, I expressed skepticism about Southerland’s commitment to reducing immigration, notwithstanding his NumbersUSA “True Reformer” rating.  I did this because of the weakness of his stated position (which, I note in passing, didn’t even make his House website), the endorsements he received from immigration lobbyists, and the fact that, in our private communications, his staff was even weaker on the subject than his public pronouncements.

    That staff is now saying candidly that Rep. Southerland has flip-flopped on question #11 of the 2010 questionnaire – “Should Congress institute safeguards that will prevent importation of foreign workers any time they would threaten the jobs or depress the wages of American workers?” – while supporting “guest-worker” schemes and possibly even walking back his earlier support for e-Verify as well.

    How did NumbersUSA fumble this badly?  Was Southerland really the best we could do?

    A couple of possible answers:

    • With a consistent overall “B” rating, Southerland is voting much better than Allen Boyd was by the time he left office.  Our main complaint is that he seems quite content to let John Boehner spike all immigration legislation and amendments well before they make the floor.  That’s disappointing, but it’s not the same as empowering a Democrat majority that’s actively trying to destroy the American nation.
    • Southerland won the primary on the first ballot in a four-way race.  To the extent his nomination was inevitable, NumbersUSA may have calculated that taking his questionnaire responses at face value then and playing the betrayed constituent now gave us more leverage than backing a doomed challenger.

    Thoughts?

    Wednesday, July 04, 2012

    Happy Independence Day

    Enjoy it while you have it.

    Millennium Challenge 2002 (MC02) was a major war game exercise conducted by the United States armed forces in mid-2002, likely the largest such exercise in history. The exercise … cost $250 million, involved both live exercises and computer simulations. MC02 was meant to be a test of future military “transformation”—a transition toward new technologies that enable network-centric warfare and provide more powerful weaponry and tactics.

    Red, commanded by retired Marine Corps Lt. General Paul K. Van Riper, used old methods to evade Blue’s sophisticated electronic surveillance network. Van Riper used motorcycle messengers to transmit orders to front-line troops and World War II light signals to launch airplanes without radio communications. … In a preemptive strike, Red launched a massive salvo of cruise missiles that overwhelmed the Blue forces’ electronic sensors and destroyed sixteen warships. This included one aircraft carrier, ten cruisers and five of six amphibious ships. An equivalent success in a real conflict would have resulted in the deaths of over 20,000 service personnel. … Another significant portion of Blue’s navy was “sunk” by an armada of small Red boats, which carried out both conventional and suicide attacks that capitalized on Blue’s inability to detect them as well as expected.

    At this point, the exercise was suspended, Blue’s ships were “re-floated”, and the rules of engagement were changed. … The war game was forced to follow a script drafted to ensure a Blue Force victory. …

    HT:  Robin.

    On the other hand . . . how come none of our actual adversaries ever manage to pull anything like this off?  In practice, our enemies excel, not at lightning victories, but in wearing us down over years with low-intensity methods like IEDs.

    Monday, July 02, 2012

    Obamacare and Bankruptcy

    As disappointing as last Thursday’s SCOTUS ruling was, I have always recognized that if there is any Constitutional limit on Congress’s ability to use the tax code to incentivize some personal decisions and discourage others, the case law hadn’t gotten around to finding it yet.

    The legal problem is that the legislation John Roberts ruled on isn’t the legislation Congress actually passed.  Substantively, however, I am less concerned with the Individual Mandate than the implications for national solvency.

    Case in point:

    On June 7, 2012, the House passed the Healthcare Cost Reduction Act (HR 436), a bill I [Congressman Mike Turner] cosponsored to repeal the 2.3 percent excise tax on medical devices enacted as part of President Obama's healthcare law. This legislation, which passed the House with strong bipartisan support, is similar to a bill I introduced last year (HR 1310) to repeal the tax on medical devices used by first responders.

    Beginning in 2013, a 2.3 percent excise tax will be imposed on the sale of life-saving, life-enhancing medical devices by manufacturers, providers, and importers. We have all heard of a cradle-to-grave government—well, this is a cradle-to-grave tax! Every item used to provide care, from the incubators used to care for prematurely born children to the rollers which move caskets, would be subject to this tax.

    More anti-tax boilerplate follows.

    I don’t have an opinion one way or another on excise taxes, except to say that PPACA is chock-a-block with little revenue boosters like this that are predictably – in fact, ceaselessly predicted by Megan McArdle and others – falling by the wayside.  Last I looked in on it, the cost of Obamacare had nearly doubled from its original projections.  And the march towards national bankruptcy continues unabated . . . .