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NASA Daily Image

Cloud streets off of the Aleutian Islands

 
Strong winds polished the snow of southwestern Alaska and stretched marine stratocumulus clouds into long, parallel streets in early January, 2012. After crossing Bristol Bay, the winds scraped the clouds across the tall volcanic peaks of the Aleutian Islands. As the wind impacted the immobile mountains, the airflow became turbulent, swirling in symmetric eddies and carving intricate patterns into the clouds on the leeward side of the islands. At the top of this image, the bright white color indicates a thick layer of snow overlying the land of southwestern Alaska. The pristine white is broken by the rugged Ahklun Mountain Range in the east, which is partially covered by a bank of clouds. Off the coast of Alaska, sea ice floats in Bristol Bay, cracked and chipped by the flow of the waters which lie underneath. A few cloud streets – parallel lines of clouds – can be seen in the far northwest over land. The clouds increase over the sea ice and become thick over open water, where row upon row of clouds lie close in perfectly parallel formation. The Aleutian Islands stretch from northeast to southwest across the image. Sea ice, which is bright white here, lies on the windward side of the islands. A few of the tallest volcanic peaks can be seen rising from the icy islands. The character of the cloud streets change as they impact the Aleutians, especially near the center of the image, where two rows of beautifully symmetric swirls of eddies in the clouds stretch across the sky. These swirling formations are known as von Karman vortex streets. This true-color image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite on January 11, 2012. Image Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team
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NOAA OSEID

NOAA's Operational Significant Event Image of the Day

That Middle Seat, Revisited

In “The Family, the Middle Seat, and You,” I asked what you would do in that scenario. Here’s what happened.

The passenger did, in fact, relinquish his aisle seat for the middle, and the passenger in the family’s row on the aisle then moved back one row, beside the passenger in question.

The aftermath:

As the flight attendants wheeled their carts forward to begin their drink service, the flight attendant who had helped the family initially calls over to her colleague in the other aisle, points to the passenger who had moved to the middle, and says, “Whatever he wants is on us.”

The Family, the Middle Seat, and You

I was flying to the east coast the other day, non-stop from San Francisco to Washington Dulles. I had taken my seat and was settling in (“feathering my nest,” as I like to think of it). A women with her two children, about 12 or 13 and about 8 or 9, arrive at a nearby row. The woman asks the flight attendant if there was a way the three could be seated together: they had been unable to reserve contiguous seats, and one would be in the row behind. The flight attendants looks at the boarding passes, surveys the area, and sees she has an aisle and a middle together, and an aisle in the row behind (2-3-2 seating on this plane).

“I don’t expect anyone will switch with you, since it would mean changing from an aisle seat to a middle. And then, this gentlemen would have to be willing to move back a row.”

Pause for a moment, and consider: what would you do if you were in one of those two aisle seats surrounding the lone middle seat?

Really think about this. It’s a five hour flight, and you’ll be stuffed into a middle seat for the journey.

What would you do?

You Can’t Start a Fire Worrying about Your Little World Falling Apart

Metaphor in Teaching

Metaphor is one of the most powerful tools available to teachers.

I was talking with a friend and former colleague, Mark. We met when I was at NeXT: initially, he was one of my customers; he later came to work at NeXT. Among the other Insanely Great™ experiences I had at NeXT, I taught a very advanced class on our network administration system, NetInfo. We delved deeply into the bowels of the system: concepts, architecture, IP underpinnings and broadcasting (along with a side trip down netmasks—including non-contiguous netmasks—and routing), SunRPC, and on to the packets on the wire with some real-time sniffer trace analysis.

Part of the architecture includes a newly booted node finding it’s “parent” NetInfo server: a server for the parent domain in the domain hierarchy. My son was somewhere around 4 years old then, and Are You My Mother by P.D. Eastman was among our favorite books. The book relates the story of a little bird who, having fallen from its nest, goes in search of its mother. The bird, not knowing what its mother looks like, nor realizing that its mother would look rather like itself, asks each animal it sees, in turn: “Are you my mother?” It struck me that, though we were talking about a “parent” server, I could cast this as the newly booted NetInfo node looking for its “mother.” I incorporated the nomenclature, and the book, in my class, and drew the analogy of the NetInfo client searching for its mother on a network with a number of potential NetInfo parent servers. To me, the classic, defining dialog from the book (thanks in no small part to another good friend’s having introduced the book to me with this dialog) is:

“Are you my mother?” [the little bird] said to the cow.

“How could I be your mother?” said the cow. “I am a cow.”

Fifteen years or more later, Mark related that every time he reads Are You My Mother to his children, he remembers the class. Apparently, the metaphor struck home, and helped cement the idea of the node looking for its parent server. At the very least, it was memorable!

Metaphor won’t replace a teacher’s being knowledgable. Metaphor won’t replace a teacher’s being experienced. Metaphor won’t replace a teacher’s truly caring. However, metaphor, backed by knowledge and experience, and coupled with caring, can result in a long-lived and powerful learning experience.

One Real World Volt Snapshot

Trip to San Francisco this evening for some hoped-for but unrealized sunset photography, dinner, and a friend’s wedding celebration. Simplified my life and just left the car in Normal Mode the entire trip, instead of switching to Mountain Mode (lousy excuse for Hold Mode—hold the battery right where it is, please—but all that’s available in the US Volt; the idea is to reserve some charge in the battery for the in-town stop-and-go city driving, where an ICE [internal combustion engine] tends to be at its least efficient). 79 miles round-trip, including I-280 to Brotherhood Way, pushing the speed a bit, rather than the flatter, more sedate, and more efficient US-101. (But, I-280 is a much prettier drive!) Battery was fully drained before reaching the City.

Got 37 miles on the battery, 42 on the ICE; burned just over a gallon of gasoline. Counting only the gas, that’s 75 mpg for the round-trip, and 40 mpg for the ICE-only portion. Energy consumed: about 10.5 kWh off the battery (it takes about 11.9 kWh to charge the battery using the 240V charging system, 12.2 kWh using the 120V charger), 138 kWh from the gasoline via the ICE to drive the generator, yielding a total energy consumption of about 150 kWh.

Getting a little more precise yields an MPGe of 69.3 if you include the charging inefficiencies, 70.0 if you exclude those. MPGe is “miles per gallon equivalent”: convert the energy used from the battery into the equivalent amount of gasoline, using the following conversion factors:

  • 1 kWh = 3.6 MJ (megajoules).
  • 1 liter of automotive gasoline yields 34.8 MJ of energy; 1 gallon, therefore, has 131.7 MJ, or  36.59 kWh.
  • The Volt’s battery provides 10.4 kWh (the battery actually has much more energy than this: 16 kWh; the on-board battery management system limits a full charge and the depletion level to improve battery longevity).
  • A 240V EVSE (“electric vehicle service equipment,” the industry’s technical term for a “charging station” or “charger,” since the actual charger is in the car itself) runs at about 87.5% efficiency (based on energy used from the grid and energy stored in the battery). A 120V EVSE runs at about 85.5% efficiency. These numbers are based on follow Volt owners’ actual, measured consumption: I don’t have the ability to get these numbers from my installation.

Remembering and Visualizing

As we approach the a marker in the endless circle of life, of seasons, of the year, I reflect on the past to inform my thoughts of the future. We spend so much time analyzing our failures so we don’t repeat them. It’s equally important to understand our successes so we can repeat them, apply the techniques again.

It was late in the summer fifteen yeas ago. Three of us, Elaine, Marty, and I, were in the final stages of getting ready to lead High Holy Days services—our congregation’s first such communal observance, though we were a few years old. We had assembled our machzor, drawing from several sources (carefully securing permission to include the excerpts when they were copyrighted, writing some original liturgy, engaging a significant part of the community in the effort). Elaine served as editor of the machzor; I chaired the committee charged with planning and executing and realizing our goals, our vision of more than just our own High Holy Days service, but making those the kind of services we wanted, including everything for liturgy and ritual to venue, from finding people who would lead services to people who could deliver a great collection of drashes, while also realizing our value that they be freely open to the community at large.

I had been asked to lead Erev Rosh haShanah services, on a Friday evening, the very first part of the High Holy Days collection of services. As I prepared for this, learning new liturgy and new melody, I recognized that I also wanted to prepare emotionally. Thanks to some good teachers regarding such things—in particular, Lanny Bassham, an Olympic champion—I knew that if I wasn’t ready, if I didn’t review and prepare in every way possible, there was a high chance that I would not provide the kind of experience for our congregation that I wanted to provide. I wanted people to feel comfortable, to be confident in me as I led services, so they could focus on their own experience and their own spirituality, rather than wondering when the poor fools up there on the bimah would make yet another jarring mistake.

Besides being technically prepared, I also had the feeling that the situation could prove overwhelming. In sports, it’s called “match pressure,” and I knew what it was like both to handle it well and to handle it poorly, to succumb to it and to master, from my own experience, from that of my teammates, and from other competitors and teachers, such as Lanny.

I had been taught that the best way to handle match pressure was to experience it, to become accustomed to it, and to learn how to harness it. (Harness, not eliminate: match pressure can lead to additional adrenaline in the blood, which will enhance perception and kinesthetic awareness, among other things, allowing a trained competitor to perform better. Unharnessed, though, match pressure leads to nervousness, distraction, and loss of concentration and focus.) I decided to harness a tool Lanny, and others, had taught me, a tool that allowed one to experience something without actually doing it: visualization.

Odd though it seemed to me at first, I learned that vivid visualization, done well, causes the body—muscles, nerves, brain, etc.—to respond in ways similar to living the actual event. As I thought about this when I first was exposed to the concepts, a dozen and a half years before the High Holy Days preparation, I realized that it was just like dreaming. Sure, I had awakened from nightmares as a youngster covered in sweat, heart beating jackhammer-fast. A dream is just an example of vivid imagination, one so vivid that the mind cannot differentiate it from reality. It made sense that we could learn to harness this, especially as I heard elite athletes’ experiences with the techniques.

Why do we train? To improve performance: performance in the match, performance in the game, performance during the real event such as an emergency or a space flight. The goal? Make the actual event “just like drill,” or, perhaps, even better.

I decided to visualize myself leading services.

The challenge became visualizing what would really happen: leading from the bimah instead of in the round, with a congregation of 350 instead of 50, with new melodies instead of ones that were years familiar, with new liturgy instead of that which I had prayed many, many times. I had to become technically competent before I could visualize effectively. I had to learn the melodies and understand the liturgy so that I could begin to experience things accurately in my head. It turned out that these were the easy things, and the simple things. The difficult bit? Putting myself in a frame of mind as close to what I would experience that Friday evening as possible, experiencing the emotions as fully as I could.

Why the emphasis on the emotions? I knew how powerful an experience this could be. I knew how important it was to us as a community, and to me personally. I knew how much I had invested in this, how much work we had all put in. I knew that the first experience people had, that first night, could well affect whether people returned.

I knew I wanted to succeed.

I knew what my own definition of success was.

It was, indeed, not easy, nor simple. I took as many little bits of time as I could, even a few minutes, to go through what I would do in each part of the service, and then to experience it as vividly as I could while relaxing on the couch or laying in bed or sitting out in the sun. I made the time to run through the entire service, repeatedly.

I was, yes, a little nervous during the final few minutes of preparation that Friday evening. Once we started, though, the nervousness vanished. From what people told me afterwards, services went very well. From my perspective, I remember two things.

First, I really did feel like I had been at services, that I’d had a spiritual and fulfilling Erev Rosh haShanah experience, not simply that I had performed on stage. That was very much part of the goal, to be so comfortable with the technical things, with the performance aspect, that I could be fully there. I didn’t want to feel like I had to concentrate on the content or the liturgy or the songs, but that I could concentrate on the people there and connect with them, that I could concentrate on leading services and helping people have the experience they wanted.

Second, and the most vivid memory, was when I was asked how I thought it went. My answer: “Exactly as I expected.” I had, after all, done it dozens of times already in my imagination.

As I remember this, I think about harnessing that power. I think about the things I want to do, to happen, to experience, to accomplish. I think about applying these techniques to other things, to attaining other goals. I think about sharing these techniques with others. I also reflect on having good teachers, and I am grateful.

Here’s to a good new year: !לשנה טובה