Acme

In fact that is not all you are doing. For lack of a better term, I'd call your posting in this thread 'trolling'.

While tsunami danger is unlikely, you're not free & clear of severe quake hazards. North Carolina Earthquake History Not 'really big ones', but not safey wafey either.

In the US these reading lists are submitted by teachers and approved or not by school principals and/or school boards. Moreover, the required readings are often challenged by students or parents and subject to review. As to why certain books are recommended I think you would have to ask the individuals who recommend them and I expect their answers would be quite variable.

From that one: Thumbs up. No; that does not follow. IOW, it's a logical fallacy. What has also been covered is that laws are amendable and many of us have given reasonable arguments as to why many of the laws governing guns should be amended.

Gun locks that fit in the trigger guard like the Master 90 shown above are a poor choice. The padlock that came with my gun has a long shank that goes through the receiver and down the magazine shaft. In a locked condition the gun can't even be loaded. As I noted earlier, my gun also has an internal lock which renders it unusable even if it is loaded and a round chambered. Also as I noted earlier, this feature is required by law in some states and I think a federal law of the same kind is a good idea. Granted this only secures new guns, but it's a step in the direction of sensibility. Having any lock on a gun with the expectation that you can access it [quickly] when needed is a fool's illusion. If your aim is to have a gun for protection then it needs to be on your person, and even then it's no guarantee you'll get to use it at all, let alone effectively. If the gun is not on your person it should be secured in such a way that no one can get it or use it without considerable trouble, if at all.

Perhaps you mean the 1700 quake, as I see no references to one in 1600. I find your citation unreadable as I can't zoom in nor read whatever language it is in. Can you quote a germane translation?

True. However that's not to say we've nothing to worry about if that's your implication. They go on to say: The article you cite mentions 13 previous quakes but they list only 6. Quoting from the Wiki article I cited in post #25 on the Cascadia subduction zone: So, averages are as averages do and they are no substitute for monitoring and study when there are so many lives and so much property at risk.

I always use PNG, when not using PSD (PhotoShop Document). Can we have our cake and eat it too? Mmmmm...I opened my original bug pic above to see if Photoshop had that EXR, which it does not. It does have a Save As RAW option though, which I never noticed. Is there any advantage to use that for the jpgs from my camera? I also notice the bug pic I posted is a jpg, so I must have been in a hurry. I usually don't do more than 1 edit on a single file, so I don't think I suffer the lossiness you mention. My typical operation is to load the original jpg, then Save As PNG using same file name and adding a code letter. Then I edit the PNG and save it. I also have a habit of then loading the edited file into Paint, selecting all and copying, and then making a new file, pasting to it, and saving it with same file name but with different code letter. I do this to strip the EXIF data which I consider nobody's business but my own. The bug pic above followed that procedure except that I kept the jpg format. All-in-all, photography is a fun hobby by itself and a valuable addition to many other science hobbies.

Roger. I will play around with that. Also roger. I had heard/read about the lossiness and that's why I was converting them. I'm something of a newbie to the digital realm and appreciate any help. The jpgs are definitely smaller and the pngs became an issue with my submissions to the university because I have an e-mail attachment limit, which prompted me to get a Dropbox. Fortunately I have saved all the original jpgs so I can go back and do some experimenting. Afterthought: Here's a link to the free camera manual in PDF format with all specs and features: Nikon COOLPIX L830 - Reference Manual Hobbyists love free. I saw insect collecting mentioned earlier, so I'll bug y'all a bit further with some of my hobbying.

The camera does have a collection of white balance filters [auto/daylight/incandescent/fluorescent/cloudy/flash] and I can manually adjust exposure/brightness + or - to some degree. Unfortunately this model saves all images as jpg and has no raw option. I usually convert the images to png in Photoshop and then process those using mostly the unsharp mask and contrast/brightness filters.

Thnx. I'll look into the commercial jobs. I have tried shining in light using LEDs, but I wasn't happy with the color. My 'lab' is a table by a window which gives me natural light. My thought on the home-made ring is to have the plastic extend out beyond the lens to collect the natural light and to bevel the inside edges to cast the light downward. Besides the close and small, my camera has given me the best far and large photos that I have had since film days. As ajb mentioned astronomy hobbyists: I caught this shot of the Moon on August 22 when smoke from forest fires East of me swept down the gorge and filled the air. I scaled down the seed images, but this one I'll put up full scale. I have taken even sharper Moon images when the sky was clear. Alas the auto-focus of my camera made getting focused shots of the recent Jupiter/Venus conjunction impossible.

Yes, native Americans kept the oral history and eventually passed it on to researchers. From Wikipedia: Further field research of submerged forests and debris fields has revealed the details of much earlier mega-quakes & tsunamis from the Cascadia fault. The subduction zone does not run to Japan, rather it's the Pacific [tectonic] plate they refer to as reaching Japan. Here's a map of the subduction zone from Wiki and a link to their article: Cascadia subduction zone @Wiki

Thanks Klaynos. The camera is a 16-megapixel Nikon Coolpix L830 digital with a 34x optical Zoom-NIKKOR ED glass lens. (More technical details at the link.) Props to our member Sensei for putting me onto it when he recommended an earlier Coolpix model in another thread. I have had it about 9 months and love it. It does lack the ability to make manual settings for f-stop and shutter speed which sometimes makes depth-of-field a challenge, but all cameras have their trade offs. Getting it on sale at 1/3 off was icing on the cake. The macro focus allows me to get within 1cm of subject, though at that distance it's difficult to get sufficient light. As a hobbyist I'm thinking of making a Lucite® light ring this Winter for lab work. Here's a sample of the lab shots I do with a rule. The background is some craft foam matting which I chose for its nearly neutral gray color. Seeds are from Dillen's Wood-sorrel - Oxalis dillenii.

Thanks Doc. While Flickr used to be mostly a storage spot, it now provides a lot of social networking functions, such as Groups, that are used by hobbyists of all stripes. Membership is free and currently you get 1 terabyte of space. Lots of sharing of info of the kind hobbyists value.

I was going to say gardening. You learn twice as much if you combine these two hobbies. Yes Sir; good point. As Yoda would say, combine them I do. You're welcome. Besides growing & photographing veggies at home, I collect native plants, seeds, or cuttings that I gather in the field and cultivate them. While I am in all ways an amateur hobbyist, I was accepted as a contributing photographer to a local university's online herbarium and have found a niche photographing seeds. The collection has very few such photographs and as a hobbyist I have an advantage over the professionals in that demands on my time are more flexible. Just one example to illustrate (if it's not a derail or imposition). I have been trying for 3 weeks to get this shot of the seeds of the Round-leaved Violet - Viola orbiculata. Once the pods mature & open, the seeds are squeezed out in short order and being less than 1mm in diameter they are lost in the soil. Rats! Yesterday, to my hobby heart's delight, I caught the perfect moment. After taking this shot I collected the seeds in a bottle for later photographing alongside a rule in my 'lab'. Well, I do run on................

Botanical photography.

De nada.

Yes the water is locked in. Tilting the pipe wouldn't change the back & forth oscillation, but the weight of the water would push the lower membrane out more and dimple the upper membrane inward more. The amount of difference would depend on the specifics of the diameter and length of the pipe and elasticity of the membrane. The water-in-a-pipe analogy to electricity is not perfect in a number of respects, one of which is that water has considerable mass and electrons have little appreciable mass. All else being equal, the electric current in a vertical conductor in a gravitational field is of no practical difference from the electric current in a horizontal conductor.

Extending your analogy of voltage pushing, we can imagine the flow of electrons as similar to water flower in a pipe. The voltage then would be the pressure and the amperage the volume. Both flows are 'currents', but we would measure them in different units. A water current we might measure in gallons per minute, and we measure electric current in amps which is coulombs per second. In the water flow, pressure would be analogous to electrical voltage, and friction would be analogous to electrical resistance. So, electrons flow in a direction through a conductor just as water flows in a direction through a pipe. Most water flows go in only a single direction, but you could get the equivalent of AC in a filled water pipe by capping both ends with a flexible membrane and then vibrating one membrane cap which would cause the other membrane cap to vibrate in sympathy due to the hydraulic pressure. The speed at which you vibrated the membrane would be analogous to the frequency of an AC electric current, how hard you pushed the membrane would be analogous to the electrical voltage, and how much water is displace by the stretched membrane would be analogous to the electrical current. Just saw your edit: No single electron actually moves from one end to the other of the wire, rather it is a succession of bumps similar to falling dominos. PS Will be leaving shortly and away from computer. Could be a couple days and don't want you to think I abandoned the subject. Many others here are well suited to answer questions during my absence.

The current. Think AC=Alternating Current and DC=Direct Current. The direction of the flow of current in a conductor is constant in DC and changes from one direction to the reverse direction in AC.

It is the polarity that is alternating from plus (+) to minus (-).

Me too. Chop chop! And as to stability, that last bit I cited actually suggests it would be a good idea for stability. Maybe it won't be too long before we start seeing quad-copters on the scale of current helicopters. ? I was also thinking about battery life issues with the model quadcopters and thought perhaps they could use a small gas engine driving a generator. Oui/no?

Well, JohnSSM said "I [am] talking about a four engine craft that tilts in the direction that it moves.". Clearly the craft flies with the battery on top or bottom, but I don't think that moves the center of mass above the rotors in either case. Maybe it does, but such multi-rotor craft are unique and only remotely operate as do helicopters so perhaps the center of mass can be above the rotors. I don't know if the rotor shafts tip or are fixed, or if they have variable pitch, but I had the impression drone rotors are fixed shaft and fixed pitch blades and that maneuvering is achieved by varying the relative speeds of the rotors. Perhaps this all varies by model. JohnSSM, can you edumacate me/us? Another thought on the battery. Use 2 batteries, one top and one bottom. This could be either 2 batteries like the standard which would add weight but extend flight time, or two smaller batteries that together equal one of the usual type. Addendum: According to this Wiki article, I was correct. Still digging on possible tilt and variable pitch rotor models. Quadcopter @Wiki Addendum addendum: So yes, some have variable pitch rotors. From the same Wiki page: Still nothing on tilting rotor shafts, but reading that page on how maneuvering is accomplished I don't see such a mechanism as being any advantage. Addendum addendum addendum So yes, the center of mass can be above the rotors. There's a sweet photo here, but the image is not linkable as this is a PDF. It's a dandy too! All kinds of equations on stability and such stuff as makes for interesting reading. Modelling and Control of a Quad-Rotor Robot Paul Pounds, Robert Mahony, Peter Corke Australian National University, Canberra, Australia CSIRO ICT Centre, Brisbane, Australia Mmmm...I should not have relied on the photo to determine the center of mass, or in their terms center of gravity. What's the diff? Checking... Center of gravity @Wiki Ok; kewl. On to the paper's clarification on the test quad-chopter. Had to add the Ozzian spellings of parameterisation, analyse, and behaviour to my dictionary. G'don those mates. Nonetheless, the rotors can be below the center of gravity. >>

I don't know the answers to the drone battery placement question, but it seems to me comparing drones to airplanes (which I presume you meant by 'aircraft') and jets is not a legitimate analog. At best you might make a comparison with a helicopter, but even then the drone is fundamentally different with it's multiple rotors. (At least 3 rotors on a drone; yes/no?) As to battery placement, well, do some experiments. Put it on top and execute a set of maneuvers and take note of performance. Then put the battery on the bottom and do the same set and take notes and then compare the performances. Depending on the results and what you want to do during flights you pick the arrangement that works best.

As imatfaal noted, stratigraphy can be helpful in dating, however once an artifact is removed without the stratigraphic analysis that usually accompanies digs, stratigraphy may be of little use in your case. Also, things get moved around so even with stratigraphic info it's possible someone else put it where you found it, or it washed in, or came by some other such accidental means. If there's other such artifacts there that you didn't find it might shed some light on the site being a trash site, or hiding place, or storage spot, or a campsite. As to which kind of vessel it belongs to, that's usually a matter for experts who have studied nuances that vary by age, style, specific material & location. As I mentioned, the only positive way to date a ceramic is thermoluminescence (TL) dating. If it is very old then calling it a relic is fine, though vessels with handles from long ago were made in great quantities and were as disposable as today's pickle jars. Not that it couldn't be some kind of unique disposable relic, but again it would take an expert to make that determination.