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Ludwik

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  1. Theists and Atheists I still do not know what can be done to eliminate endless conflicts between theists and atheists. But comments collected at several websites prompted me to compose a short on-line paper at: http://pages.csam.mo...i/theo_sci.html It can probably be used to initiate an interesting discussion here. Please share this link with those who might be interested. Ludwik Kowalski Professor Emeritus Montclair State University, USA . .
  2. How harmful is nuclear radiation? It depends on the dose/density received. Tsunami-related Fukushina accident will probably renew debates about nuclear electricity. Such debates should be based on what is known about negative effects of nuclear radiation. Numerical data below should be useful in that context. The effect of penetrating radiation on a person depends on the dose density received. The common unit of dose density is Sievert (Sv). Smaller doses are expressed in milliseverts (mSv) or microseveret. The old unit of dose density, rem, is also used widely (1Sv=100 rem) A dose density of 10 Sv will most likely results in death, within a day or two. 5 Sv would kill about 50% of exposed people. 2 Sv can also be fatal, especially without prompt treatment. 0.25 Sv = 250 mSv is the limit for emergency workers in life-saving operations. 0.10 Sv = 100 mSv dose is clearly linked to later cancer risks. 0.05 Sv = 50 mSv is the yearly limit for radiation workers. 0.004 Sv= 4 mSv typical yearly dose due to natural radiation (cosmic rays, etc). 0.003 Sv= 3 mSV typical dose from mammogram The one day dose densities, due to Fukushima accident, at a distance of 30 miles from the damaged reactors, was reported (on 3/16 and 3/17) as 0.0036 mSv. I do not have data on doses, probably very large, received by those who worked near or inside reactors. But I have no doubt that each of them was carrying an individual dosimeter. No deaths due to radiation have been reported in Japan, as far as I know. Many lives, however, were lost in Chernobyl, by those who worked to minimize damage. P.S. What I call dose density is often called a dose. But this is not correct. Sv=J/kg is dose density; the dose (how much energy absorbed in a body) should be in Joules. Ludwik Kowalski Professor Emeritus Montclair State University, USA . .
  3. How harmful is nuclear radiation? It depends on the dose received. Tsunami-related Fukushina accident will probably renew debates about nuclear electricity. Such debates should be based on what is known about negative effects of nuclear radiation. Numerical data below should be useful in that context. The effect of penetrating radiation on a person depends on the dose received. The common unit of dose is Sievert (Sv). Smaller doses are expressed in milliseverts (mSv) or microseveret. The old unit of dose, rem, is also used widely (1Sv=100 rem) A dose of 10 Sv will most likely results in death, within a day or two. 5 Sv would is kill about 50% of exposed people. 2 Sv can also be fatal, especially without prompt treatment. 0.25 Sv = 250 mSv is the limit for emergency workers in life-saving operations. 0.10 Sv = 100 mSv dose is clearly linked to later cancer risks. 0.05 Sv = 50 mSv is the yearly limit for for radiation workers. 0.004 Sv= 4 mSv typical yearly dose due to natural radiation (cosmic rays, etc). 0.003 Sv= 3 mSV typical dose from mammogram The one day dose, due to Fukushima accident, at a distance of 30 miles from the damaged reactors, was reported (on 3/16 and 3/17) as 0.0036 mSv. I do not have data on doses, probably very large, received by those who worked near or inside reactors. But I have no doubt that each of them was carrying an individual dosimeter. No deaths due to radiation have been reported in Japan, as far as I know. Many lives, however, were lost in Chernobyl, by those who worked to minimize damage. Ludwik Kowalski (see Wikipedia) Professor Emeritus Montclair State University, USA
  4. Below is a message just received from a nuclear physicist friend in Japan: Ludwik ============================================= Serious rescue efforts for isolated people in destroyed towns by tsunamis and quake are under way. Another serious concern is of the stopped nuclear power plants, Fukushima-I $II with 8 reactors total. The Fukushima-I#1, 40 years old, has got the first trouble after its automatic shut-down by the quake, which was caused by no electricity (an emergent Diesel generator did not work either) for driving circulation pumps of cooling water. Consequently, decay heat of U-fuel pins could not be cooled enough and temperature and steam pressure inside the reactor vessel elevated continuously. Finally the melt-down of reactor-core fuel started to happen, as detected by Cs and I activities outside as the emergency value of reactor vessel gas was opened to decrease the elevated steam pressure. It happened an explosion, by mixing hydrogen-gas (generated by H2O + high-temperature-metal interaction inside reactor) and oxygen gas at the outside of the reactor steel-container, which destroyed the concrete walls of the #1 plant building. The reactor container vessel and reactor vessel were looked not damaged. TEPCO (Tokyo Electric Power Corp.) and NISA (Nuclear and Industrial Safety Agency) decided to fill the inside and out-side of reactor vessel with sea-water adding borated acid to cool the reactor. The work was done. Radioactivity monitors outside showed decrease of radiation level to about ten times of natural BG, which was about several 100 times just after the emergency gas-valve opening. Now the reactor is confined stable. Citizens inside 20 km radius were evacuated for safety. (I think, the usage of sea water, emergent use, was chosen by two reasons: 1) not enough pure-water was not available at the site, 2) NaCl contained in sea water, as well as added borated acid (B-10) has significant thermal-neutron absorption effect which may help avoiding a worst criticality accident of fallen debris of melt U-fuels into water pool of container vessel, if happened.) Probably the Fukushima-I#1 reactor will be closed (disassembled) in near future. But we still need careful watching what will be going on. Now it is aired that Fukushima-I#3 reactor has got a similar trouble. They might do similar treatment, not decided yet. .
  5. M. Soltysik, one of the leaders of SPUSA (Socialist Party of the USA), was recently interviewed by M. Bonanno, as reported in an OpEdNews article: (link removed) After briefly commenting on that interview, I wrote my own PoEdNews article: (link removed) What follows is a summary of my article. 1) M.S. wants us to discuss socialism without linking it with the USSR, the first socialist country in the world. I objected to this. I think Stalinism must be studied in order to avoid Soviet mistakes and Soviet crimes. 2) Referring to capitalists, M.S. said "fat cats have had fun at the expense of the working class for way too long." What should be done with them? Are all fat cats parasitic? Was Henry Ford parasitic? Is Bill Gates parasitic? What fraction of "his" billions is invested in "our" economy, rather than consumed? What fraction is used in scientific research? I suspect that private consumption is below 1%, including luxury homes, private jets, etc. Why was the Soviet agricultural system, based on collective farms, much much less productive than our own system? What should be done with American agricultural capitalists? Should they be treated as kulaks were in the Soviet Union? Who will run our airline companies, our TV stations, our restaurants and our barber shops? Why is the SPUSA program silent on this? Do you agree that the Soviet experience should not be ignored in answering such questions? 3) The program of SPUSA, at www.socialistparty-usa.org , displays the party emblem. It calls for unity of proletarians of the world. I know this slogan very well; it was always displayed on the first page of the main Stalinist newspaper, Prawda, till 1942. What is wrong in my suspecting that the SPUSA is a Marxist-Leninist party in disguise? 4) The party program contains this statement: "The Socialist Party is committed to full freedom of speech, assembly, press, and religion, and to a multi-party system." How can anyone dislike such proclamations? The question is how to proceed without creating something that is much worse than what we already have in America. Similar promises were made by Lenin, in 1917, and we know what happened. How to avoid similar disasters? 5) The program also states that "socialists struggle for the full freedom of women and men to control their own bodies and reproductive systems and to determine their own sexual orientation." That is good. Will this struggle be easier under socialism? Those who oppose abortions will still exist. Yes, I am thinking about "freedom of speech, assembly, press, and religion" mentioned in point 4 above. 6) What do the SPUSA leaders mean by "democratic revolution"? Speculating about the future, and trying to turn dreams into reality, are attractive but sooner or later, as before, idealists will be pushed aside, by revolutionary leaders, due to "practical necessity." Soldiers do not win wars by discussing orders; they win by obeying orders. In my opinion evolutionary social reforms are more desirable than revolutions. Do you agree? I do not wish anyone to experience another proletarian dictatorship. 7) Socialism as a vision of paradise on earth? Yes indeed. But not via proletarian dictatorship! My father was a communist. But he died in Kolyma, the worst corner of GULAG, at the age of 36, about two years after being arrested in Moscow. His two letters from Kolyma, to my mother and me, are in this free ON-LINE autobiography (see the link below the signature) Ludwik Kowalski (see Wikipedia or Google) . .
  6. I would very much like to know what people on this website think about peaceful coexistence between those who study our material world (scientists) and those who study our spiritual world (theologians). My attempt to write an essay on that subject failed, as you can see at: http://csam.montclai.../theology3.html The webpage was prepared to generate a discussion. Those who post comments should refer to specific "contributions," as numbered (or to specific persons, as numbered at the beginning). This will simplify the discussion. And let us keep in mind that the main topic is peaceful coexistence. Is it possible? Is it desirable? What should we do promote it? etc. Thank you in advance, Ludwik Kowalski (see Wikipedia) .
  7. Introduction This essay is written as a homework assignment at the Memoir Writing Workshop for Senior Citizens (Tenafly, New Jersey). The workshop is conducted by Lucile Lichtblau. I am the author of a FREE on-line book, entitled: "Diary of a Former Communist: Thoughts, Feelings, Reality," at http://csam.montclai...life/intro.html It is an autobiography illustrating my evolution from one extreme to another--from a devoted Stalinist to an active anti-communist. This testimony is based on a diary I kept between 1946 and 2004 (in the USSR, Poland, France and the USA).The homework consists of describing a single fragment of my life in a short self-standing essay. I decided to focus on the the first year of the World War II. Remembering the First Year of the War Ludwik Kowalski (September 2010) In 1941, my mother and I were living in Dedenievo, a small settlement (30 miles north of Moscow) on the bank of the famous Moscow-Volga canal. The major railroad connecting Moscow with Leningrad, and a paved highway, passed through that settlement. The place was surrounded by numerous collective farm villages; I still remember their names, such as Medviedki, Tselkovo, etc. The settlement had a school, a sanatorium (where my mother worked as a nurse), a hospital, two stores, a nursing home and a post office. It also had a large, partially ruined church. The tower of that church, dominating the area, could be seen from miles away. The northern wall of the church was destroyed and a person passing by could see a huge icon of Christ, painted on the inner wall. I was always fascinated by the fact that his eyes followed me as I was passing by. I was ten years old when the war started, on June 22. That morning, in a store, I heard that our country was invaded by Germans. I immediately ran to the sanatorium, about half a mile away, to tell people what I heard. They turned the speakers on while Molotov was still speaking. Another thing I remember was the official order, distributed next day. Every tunable radio receiver--and we had one--must to be brought to the post office. The local authorities said that parts were needed by the army. Was this the main reason? Probably not; they wanted to protect us from German propaganda. After that day we had to rely on speakers connected to the central station by wires. Eleven days later I heard Stalin's first WWII speech. "Comrades! Citizens! Brothers and sisters! Men of our army and navy! I am addressing you, my friends! . . ." After telling us that Hitler's finest divisions had already "met their doom on the field of the battle," he reported that the enemy continued to push forward. I was very surprised to discover that our dear leader had a very strong Georgian accent. Posters "all for the front, all for victory," and "motherhood calls you" were to be seen everywhere. But each day we heard depressing radio announcements, such as "today, as planned, our units units left Minsk," or Kiev, etc. People had no idea what was really happening. The Soviet Union was totally unprepared for the war and losses were enormous, as we now know. The school was still functioning but about one half of our time was devoted to military matters. We learned how to deal with small incendiary bombs, how to use rifles (without live ammunition), and how to throw disarmed grenades. One day a trainload of miserable looking and poorly dressed people was brought to Dedenievo. They were said to be a labor-front division. All of them were Uzbeks; non-Russian speaking. Each morning, escorted by armed soldiers, they were led to dig trenches and build fortifications. At night they slept on the floors of a tall building, next to the one in which we had a little room. Only much later did I realize that this division was a mobile gulag camp unit. Herds of cows, sheep and horses, taken from surrounding collective farms, were led along the highway in the direction of Moscow. The policy was not to leave anything for Germans. During that time my mother and a neighbor bought a pig from a peasant in a near-by village. It was killed with a long knife and then divided into two parts, one for us and another for the neighbor. I will never forget the fear I experienced watching the killing and hearing the powerful squeals of the dying animal. Several weeks later I experienced similar fear under very different circumstances. A Red Army soldier approached me and asked about the best way to go to the other side of the canal. He was probably wounded; his bandaged arm was in a rope sling. I knew that the canal was already frozen and that it could be crossed nearly anywhere. But I also knew that it was forbidden to give any information to strangers--anyone could be a German spy, we were told. So instead of answering I said, "I know who to ask; come with me." And we walked toward the building guarded by two armed soldiers. I said that this man asked me a question that you might be able to answer. Then I left them and started going toward our home. A minute later I heard the familiar sound of a gun click. I turned my head back and saw that the guard's gun was aimed at the wounded soldier. Thinking that he was going to be killed I ran home, jumped on the bed, and covered my head with a large pillow. The fear experienced during the killing of the pig was the same as the fear I felt during this episode. The man was not killed, the guard told me later. They took him away because he was a deserter. Several days later, looking for wood in an abandoned shed, I discovered bodies of two Soviet soldiers. Were they also deserters? Perhaps they were hiding in this place and froze to death while sleeping. This kind of death, I was told later, is painless. Two weeks later, Germans were only several miles away from our settlement. One evening, probably at the end of October, the railroad bridge over the canal was blown up by Soviet sappers. Then the Red Army retreated from Dedenievo and we were between two armies, for about a week. The settlement was heavily bombed by German airplanes. The building next to the school was destroyed by a large bomb, leaving a crater about 50 feet wide and 30 feet deep. That bomb was probably designed for the church tower, suspected to be an observation point. Most of the nursing home residents died from cold after windows were shattered by numerous explosions. My mother carried some patients to the nearby hospital, on her back. Then she worked in that hospital, just across the street from the shelter where I was hiding, the basement of the church. About 100 people sat there, on tons of carrots and potatoes; the place had been used to store vegetables delivered to the government from surrounding collective farms. It is here that I heard, for the first time, about special Germans military units killing Jews and communists. I dreamed of joining partisans. At a quiet time between bombings my mother came to the church basement and said I would be better off in the hospital with her. As we prepared to leave, bombs started falling again. One hit the wooden hospital building, burying about one hundred people. We heard calls for help but nothing could be done. Then the fire started; those who survived the bomb were burned alive. The first Soviet WWII victory, pushing Germans away from Moscow, took place where we lived. A week later I walked to Jachroma, the nearest settlement from which Germans were pushed away. Here I saw two abandoned German tanks. I climbed on one of them, opened the hatch, and went inside--not a wise thing to do. Only later did I learn there might have been a mine in the tank. The constant roar of cannons became weaker and weaker. That was the beginning of a very difficult two or three years for us, due to the limited food supply. Like most people, we started growing our own potatoes, anywhere we could. We lived in a barrack, each family in a single room. Half of our space was used to store those potatoes, which we rationed to last until the next summer. In springtime we depended on eggs from birds' nests, and on fresh nettle. A little later in the season we ate birds, schav, and berries. Fortunately, I was able to help by bringing home mushrooms and fish. We were hungry most of the time. Winters were very cold. My ability to gather wood, sometimes stealing rejects from a local sawmill, was essential. Meat from the pig we bought in the fall was an important part of our diet. By spring, only a large bone remained, hanging on the wall of our room. My mother decided to preserve it for as long as possible. It was eventually used to make a very tasty soup. I was so excited to see fat circles floating on the surface of this aromatic liquid. A year later I was even more excited by the aroma escaping from an open can of American SPAM. The label on that can was "swinaja tushonka." The taste of my first American meat was the most memorable sensation in my entire life. Ludwik Kowalski (see Wikipedia) Professor Emeritus Montclair State University
  8. I remember seeing a distinction between "hard sciences," such as physics and chemistry, and "soft sciences, such as sociology. Archeology can be said to be a soft science. I remember seeing a distinction between "hard sciences," such as physics and chemistry, and "soft sciences, such as sociology. Archeology can be said to be a soft science.
  9. Last two versions of MSWORD (with document extension docx), are very different from earlier versions (with document extension doc). One of the changes is the new interface. I would vote against the new interface, if we had a referendum about it. I would argue that the 2003 version was already a very good tool; we became very familiar with it. Learning the new interface, as in the 2010 version, is a burden not worth accepting. What is gained by a typical user is negligible in comparison with what was lost. How would you vote, and why? .
  10. The methods of validation of claims (reliance on replicable experiments versus reliance on holy books) are different in these two area of knowledge. But some scientists are also deists and some deists are also scientists. Newton, for example, was active in both fields. Ludwik Kowalski (see Wikopedia)
  11. I am not convinced that your equation (4) is correct.
  12. I am Ludwik Kowalski, a retired nuclear physicist. Wikipedia will show you the link to my publications, etc.
  13. Yes, indeed. Thank you for showing the graphs. Ludwik Kowalski (see Wikipedia)
  14. I agree with this. Learning new languages only because they were added was a great pain in the neck for me. Fortran was my first language. At some time someone convinced me that I must learn Pascal, because "that is what your students are required to learn now," they said. By the time I mastered Pascal students were required to learn C. Ludwik Kowalski (see Wikipedia)
  15. Oxygen must also be available in sufficient amount. Otherwise a body will not ignite suddenly. I am sorry for reminding you the obvious. Ludwik Kowalski (see Wikipedia)
  16. I am Ludwik Kowalski, a retired nuclear physicist (see Wikipedia). My on-line autobiography, entitled "Diary of a Former Communist: Thoughts, Feelings, Reality," is based on a diary I kept between 1946 and 2004 (in the USSR, Poland, France and the USA). Google will provide the link, in case someone is interested in how a devoted Stalinist became an active anti-communist.
  17. Yes, estimating the volume should be the first step. The volume is large. The net daily amount of received energy is not uniformly distributed in this volume.
  18. You wrote: "i am shooting a compound bow at 72 lbs of draw force, the arrow weight is 415 grains and the velocity is 337fps. i am calculating my kinetic energy at 100.4 ke." Your calculated energy is 100.4 ke. What is one ke? How many joules is it? Ludwik Kowalski (see Wikipedia)
  19. What do you mean by a "nanolaser"? You wrote: "I have read about the National Ignition Facility and using lasers to create fusion. Would it be possible to build a device much smaller than NIF which uses nanolasers fuse individual nuclei of fusionable (please excuse if that's not a word!) isotopes?: All isotopes are fusionable but the coulomb barrier, preventing fusion, increases with the atomic number. Ludwik Kowalski (see Wikipedia)
  20. Actually, n should be replaced by (n-1). But that does not matter when n>>1 Ludwik Kowalski (see Wikipedia)
  21. I agree. But make sure there is a layer of air (5 mm is enough) between the laptop and the table. This can be done in different ways, for example, by taping four short "legs" to the bottom of your laptop. Ludwik Kowalski (see Wikipedia)
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