Victorian society and life style Essay Example for Free

Victorian society and life style Essay This essay uses A Conan Doyle interpretation of three cases in the adventures of Sherlock Holmes, to demonstrate how language, setting, characterisation and the role of the women reflects different aspects of Victorian society and life style.  A Conan Doyle uses typical language that is relevant for the Victorian period. In each of the cases, we expect to find a wide range of techniques used to emphasise and create an image of Victorian society and lifestyle in the readers mind. A Conan Doyle applies figurative language, repetition, grotesque and satirical caricatures and long complex sentences with detailed description. These techniques that A Conan Doyle uses helps the reader to understand the setting and characterisation more distinctly and clearly.  A Conan Doyle uses figurative language to make the reader create an image in their heads of the character or setting. Figurative language is a range of metaphors and similes that are being compared to a person or thing. Here is an example that A Conan Doyle has used in the speckled band (description of Dr. Roylott), high thin fleshless nose gave him some what resemblance to a fierce old bird of prey. In this quote the author is comparing Dr. Roylotts facial features to a fierce old bird of prey, this a metaphor used to help visualise the characters appearance. A Conan Doyle uses grotesque and satirical caricature in some cases. He uses this technique to describe the villain. In the description of Dr. Roylott in the speckled band, A Conan Doyle makes the readers imagine how nasty Dr. Roylott looks by putting in, bile shot eyes. This makes the villain more imaginative and easier for the readers to picture as unpleasant and mean.  A Conan Doyle uses long complex sentences to make a character or setting bold and clear, so the readers can easily relate and become more involved in the adventures. In long complex sentences A Conan Doyle uses Victorian words. These words are not often used today, so readers can really understand the distinct differences between today and back then the Victorians used very old English, however by using these words the reader is given a bolder, clearer and much more of a characteristic image. A Conan Doyle uses very long complex sentences to describe the king of bohemia in the scandal in bohemia, completed the impression of barbaric opulence which was suggested by his whole appearance. This gives the readers a clearer and detailed description of the event. In the quote it says he came with an uncultural but rich appearance focusing on detail. The sentence is considered complex as it uses more than one clause and unusual and uncommon words and metaphors where not familiar the words and terms i.e. opulence. In Victorian history women were be considered weaker than men. The readers can see this through some of A Conan Doyles cases. The man with the twisted lip women were really clumsy and weak. The readers can see this from the way Mrs. St Clair always kept fainting at the sight of blood, Mrs. St Clair had fainted at the sight of blood., however there were some woman that were really sly and cunning, like Irene Adler from scandal in bohemia, when she tricked Sherlock Holmes and eloped with her fianc, how best plans of Sherlock Holmes were beaten by a womans wit. In Victorian times women were really weaker than men. The second stain describes a clumsy woman, where a man blackmails a woman for a letter that could start war with another country. The weakness shows as she gives in to the man, in return for my secret not to be let out, he told me to get the blue envelope in the box. So I did A Conan Doyles thee adventure of Sherlock Holmes, gives readers an image of how Victorian London appeared. Readers are given the impression that Victorian London was a very dull, dirty and contaminated place. In most cases Victorian London was very nasty, dirty and a scary place, especially the way it is described in the man with the twisted lip. The setting in the man with the twisted lip is realistic, as at the same time jack the ripper was known, upper swandom lane is vile alley. This quote gives the reader an impression that Victorian London was very unclean and dirty. Steep flight of steps leading down to a black gap like the mouth of a cave. This quote gives the reader a frightening and dull suspense like of the setting and atmosphere. Dr. Watson is at the top of the flight of stairs and he is looking down them, when he looks down them he sees that the stairs lead to total darkness. The reader imagines a never-ending staircase or something gruesome waits at the bottom. In the adventures of Sherlock Holmes readers are able to understand Victorian lifestyle. This can be identified through the character Sherlock Holmes. In each case Sherlock Holmes is considered to be the hero as he is described as a, professional investigator. Dr Watson describes positive factors regarding Holmes, he admires, the rapid deductions, as swift as intuitions, and yet always founded on a logical basis, with which he unravelled the problems, which were submitted to him. This quote shows how Sherlock Holmes was dedicated to his work. Another example of the values of the period is seen through the character Dr.Watson. In the story the man with the twisted lip we see Dr.Watson helping a woman in distress, because her husband is missing, so he investigates by himself, I could manage it better if I were alone. This was considered very heroic at the time. As he is protecting the innocent woman. The character of Dr Roylott from the speckled band shows the readers the values, which were despised of at the time. In the speckled band Dr Roylott is described as a furious and violent person, Holmes the Scotland yard jack-in-office and, we heard the hoarse roar of the doctors voice, and saw the fury with which he shook his clenched fists at him. From these quotes the readers can tell that Victorian people despised this sort of attitude, because he turns violent and furious easily. By reading Sherlock Holmes the readers find many lifestyles, it just depends on which character is described. If it is a poor person then there lifestyle is at the opium den where it is a, low room, with thick and heavy brown opium smoke, and back in the Victorian times there were a lot of poor people, so the opium dens wouldve been packed, forecastle of an emigrant ship. If it is a heroic person like Sherlock Holmes or Dr Watson than their lifestyle is rich and cosy lifestyle for example a house with a maid, big cosy armchair, in front of a big chimney fire in a, cheery sitting room, with a nice friendly atmosphere. But if it is a villainous and hated person like Dr Roylott then their lifestyle will be dark, very gloomy and unpleasant, for example an old wrecked house that nobody has cared for, the few acres of bramble covered land.

Proposals Relation to the Education of Youth in Pennsylvania Essay Example for Free

Proposals Relation to the Education of Youth in Pennsylvania Essay In the â€Å"Proposals Relation to the Education of Youth in Pennsylvania, Philadelphia,† 1749, Benjamin Franklin reconciled public service, the benefits of classical learning, and the necessity of practical training for young people in the colony. Mr. Franklin discussed that knowledge helps to give honor. Not just honor to yourself for knowing what you are doing and talking about but, also an honor for your country to represent them if you were to become a part of office and have to communicate with others outside of country. Not even just to be in office but, to also become a minister or priest for a religion thanks to the studies of religious and civil morality. Thanks to their knowledge the academy will give to them they will be able to help their country in not just honoring them but, helping the citizens in the country. Due to their knowledge they will be able to give the citizens fair amounts of income, fair prices for taxes, and prayers. The men that will have this knowledge will not only be from a rich background with an abundance of money and high class families. As well as, poor background young men with little money and probably no family at all have a chance to receive an education and help their country. Then after one school is built to help young men, more and more can be built by other men with knowledge and help others get the education they once received. In this academy the students will learn similar subjects to what the modern day student learns today. Students will be taught the English language by reading some of the best authors in the 1700’s. There was Tillotson, Pope, Cato’s Letters, and etc. hould be some of the classics read. They will be taught to write with neat handwriting, swift drawing of arithmetic, accounts†¦ geometry, and astronomy. All of these can count as basic classes to help with any future job the student might want to have/achieve when they graduate. These basic classes can also help with everyday jobs, for example, directions in the stars while on a journey in the ocean or lost in the fore st (science), buying or trading goods for money (math), or even just being able to read and write a form of a constitution or charter (grammar). Benjamin Franklin also states â€Å"But art is long, and their time is short. † in paragraph 8 of â€Å"Proposals Relation to the Education of Youth in Pennsylvania, Philadelphia,† 1749. In the passage, the author also talks of the necessities of practical training which has to do with knowing how to handle and work on machines and the histories on machine. Something that will be taught is the machines used in wars. Men can learn to make these machines and use them. Then they can improve them in ways to make them better so they can be used when needed. The knowledge of machines can help those week men that cannot do much physical work can invent new machines to reduce labor for all men and slaves. Manufacturing companies will begin to grow in ways of money and making more of what they sell. Their money will flourish and the companies will gain power. Once the companies grow, trade will also increase which can make that country gain more money also. That is when math and grammar also come in handy. Manufacturing companies will not only flourish but, farming as well because of the farming technique they give you, to plant cash crops and even plant your own foods to eat at home. Benjamin Franklin put to rights that public service, the benefits of classical learning, and the necessity of practical training for young men in the colonies by giving them knowledge to honor and help themselves and country. Next, the students learning the basics will help with future jobs and everyday lives. Lastly, the men learn to use and invent machines by learning their histories and how they were used. These arguments should make anyone want to open up an academy and teach young men.

Impact of the Manhattan Project

Impact of the Manhattan Project How the Manhattan Project changed the world Nuclear weapons. Some love them, others despise them. Some say there use was necessary to win World War 2, others think that their use was the product of overzealous nations looking for war. There are multitudes of arguments that surround this deadly weapon. The start to the first developed and working nuclear weapon are all tied to the Manhattan project. What forces were behind the decisions to drop the bomb? What were the the immediate effects of the bomb? What were the effects years later on the world? The Manhattan project was the code name for a secret experiment That was conducted in America During the time period of World War 2. A group of refugee scientists which included Enrico Fermi, Leo Szilard, and Albert Einstein, Realized nuclear reactions were possible, and could be weaponized. Albert Einstein wrote a letter to Franklin D. Roosevelt, who was the President at that time. †Some recent work by E. Fermi and L. Szilard, which had been communicated to me in manuscript, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration. I believe therefore that it is my duty to bring to your attention the following facts and recommendations: In the course of the last four months it has been made probable through the work of Joliot in France as well as Fermi and Szilard in America that it it may become possible to set up a nuclear chain reaction in a large mass of uranium, by which vast amounts of power and large quantities of now radium-like elements would be generated. Now it appears almost certain that this could be achieved in the immediate future. This new phenomenon would also lead to the construction of bombs, and it is conceivable though much less certain that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well prove to be too heavy for transportation by air. The United States has only very poor ores of uranium in moderate quantities. There is some good ore in Canada and the former Czechoslovakia, while the most important source of uranium is the Belgian Congo. In view of this situation you may think it desirable to have some permanent contract maintained between the Administration and the group of physicists working on chain reactions in America. One possible way of achieving this might be for you to entreat with this task a person who has your confidence and who could perhaps serve in an unofficial capacity. His task might comprise of the following: a). To approach Government Departments, keep them informed of the further development, and put forward recommendations of Government action, giving particular attention to the problem of securing a supply of uranium ore for the United States. b). To speed up the experimental work, which is at present being carried on within the limits of the budgets of University laboratories, by providing funds. If such funds be required, through his contacts with a private person who are willing to make contributions for this cause, and perhaps also by obtaining the cooperation of an industrial laboratory which has the necessary equipment. I understand that germany has actually stopped the sale of uranium from Czechoslovakia mines which she has taken over. That she should have taken such early action might perhaps be understood of the ground that the son of the GErman Under secretary of state, Von Weizsacker, is attached to the Kaiser-WIlhelm-Institut in Berlin where some where some of Americas war on uranium is being repeated.† Einstein This letter is one that Einstein wrote to FDR, had a hand in creating the Manhattan project. In this letter Einstein clearly outlines that an atomic bomb is theoretically possible, and that the United States should begin research into this new deadly power, and that Germany may be researching it as well. At that time very little was known about the theoretical bomb other than it would be highly destructive. In 1940, FDR made $6,000 available to start research of this new technology. By 1945, at the end of the project, the cost had grown to around $2 billion. Within those years, 2 years were used to invent a method to make fissionable uranium or plutonium. By summer of 1945, enough fissionable plutonium had been created to make a bomb. The first ever atomic bomb was dropped at 5:30 am on July 16, 1945, at a test field in Alamogordo air base, 120 miles from Albuquerque, New Mexico. The bomb produced a blast power of between 15,000 and 20,000 tons of TNT, and fused the surface of the gr ound up to 800 yards away to glass. J Robert Oppenheimer said this about the new deadly weapon. â€Å"The atomic bomb made the prospect of future war unendurable. It has led us up those last few steps to the mountain pass; and beyond there is a different country.† (Brainy Quotes 1) A month afterwards, two more bombs that were produced by this project, which were later dropped on Hiroshima and Nagasaki. Editors of (Encyclopedia Britannica) Between the time of the bomb just being a concept that some scientists discovered up to the time of the end of World War two there were two Presidents in office. The first was FDR, and the second was Harry Truman. FDR authorized, and started what became the Manhattan project after he received a letter from Einstein telling him of an amazing but scary new technology, but The decision of whether or not the bomb should be used to try and end the war was most likely the hardest thing President Harry Truman ever had to do. The Americans were tired after 4 years of fighting, and the Japanese had a standing army of 2 million strong on there last islands. Before the 2 bombs were dropped the Allies asked for unconditional surrender, which was turned down by the Japanese military, but there was some indication that a conditional surrender might have been possible. Trumans answer to why he did it was to save lives. It sounds contradictory but experts say that an estimated 1 million casualties w ould have happened on the allied side in a Normandy type landing that would have been staged to enter Japan. Truman also said he was in the end saving more Japanese lives as well. Scientists at the time did not realize how dramatic the effects of radiation sickness were, so at that time Truman saw little difference in atomic bombing Hiroshima than fire bombing it. â€Å"The atom bomb was no great decision. It was merely another powerful weapon in the arsenal of righteousness.†Ã‚  (Brainy quotes) Some say there were other motives in using this bomb as well. Critics said that the bomb was not only the final shots of World War 2, but the beginning shots of the Cold War. us history.org page The approximate casualty numbers are difficult to determine due to the chaos and destruction that inused the bomb that decimated such things as hospitals and other government installations. The atom bomb named Little boy was dropped on Hiroshima, 135,000 out of the 255,000 existing population became casualties. 66,000 of those 135,000 were wounded fatally while the other 69,000 were injured. These numbers are more than double those from the bomb that was detonated in Nagasaki. The casualty numbers in Nagasaki were 64,000 total, with 39,000 deaths and 25,000 being injuries.The top cause of death from the explosion in Hiroshima was burns at 60%, with fall debris being the second at 30%. The causes of causalities in Nagasaki were 95% burns and 5% other. Henry pg 12 The burns caused by the bomb were called â€Å"flash burns†, because they were caused in tenths of a second. These burns are very similar to severe sunburn. The burns only occured on exposed or lightly clothed skinned. These burns were reported to have occurred up to 13,800 feet away from ground zero in Nagasaki. There was even a confirmed case of a newspaper that was 1  ½ miles away from the explosion had only its black letters burned out of the paper .Henry pg 17 Injuries caused by radiation included epilation(loss of hair), bleeding into the skin,inflammation of the throat and mouth, diarrhea, fever, and vomiting. Platelet (coagulation agents) numbers were also reduced, which caused any bleeding to be more prolonged than normal. Deaths from radiation poisoning started about 1 week after exposure, peaked in weeks 3 and 4, then they were nonexistent by week 7 to 8. Henry pg 24 One man (William o. Morse) sent a letter into a paper saying â€Å" the bomb is precisely what war is today. . . a senseless, dirty, brutal operation†. This kind of outright bluntness and honesty was rarely seen in other people, who were more subtle than outright saying that the Japanese deserved to die. A few weeks after the first bomb was dropped, a poll was taken of the American publics reaction to the bomb, and 85 percent said that dropping the bomb was a good idea. Diana steele After the war The Soviet Union wanted guarantee that such slaughter wouldn’t happen in the Soviet Union again, so they set out to spread Communism to the countries around them. Joseph stalin, the leader of the Soviet Union at the time was ruthless. â€Å"Death solves all problems no man, no problem†. (Brainy quotes 3) America could not sit by idle as this happened, so this is how the Cold War was started. The Cold War was the biggest concern of our government for the next 50 years. Also, Germany was divided into four sections, each to be de-Nazified and democratized. Russia Elected a communist regime in the east, to create a buffer so Russia could not be invaded. Winston Churchill called this the â€Å"Iron Curtain†. The war also created the UN. Examination of the period between World War 1 and World War 2 showed a lack of international communication and spirit. A strong body of nations like Woodrow WIlson had envisioned was required to keep countries from ripping each other apart, thus the UN was born. Nuclear weapons have been with us since the 1940’s, and will most likely be with us till the extinction of humanity. All of these things stemmed from Einsteins idea of a research group for this new nuclear technology, that became the Manhattan project. The bomb was created under the watch of FDR, then Harry Truman, who decided to drop the bomb. The bomb resulted in being more horrible than predicted, and wrecked havoc where it was dropped. Even today whenever war is mentioned, nuclear weapons almost always come to mind, and are something that is feared deeply. Citations Primary resources 1 Brainy Quotes. 1 Bookrags media network. web page. 5/1/14 http://www.brainyquote.com/quotes/authors/j/j_robert_oppenheimer.html 2. 1 Brainy Quotes. 1 Bookrags media network. web page. 5/1/14 http://www.brainyquote.com/quotes/authors/h/harry_s_truman.html 3. 1 Brainy Quotes. 1 Bookrags media network. web page. 5/1/14 http://www.brainyquote.com/quotes/authors/j/joseph_stalin.html 4 Einstien, Albert. F. D. Roosevelt August, 2, 1939. http://www.livebinders.com/play/play_or_edit?id=387006 szilard couldn’t convince enrico that the a bomb was possible and he wouldn;t conduct experiments. He then turned to albert einstein. Einstein then turned to president roosevelt with the issue, and urged him to take action . secondary resources 1. Diana Steele. users.dickinson. 1. dickinson. web site. 3/3/2014. http://users.dickinson.edu/~history/product/steele/seniorthesis.htm This secondary source gives information about how certain people and the general population reacts to the use of this weapon. 2.Editors of Encyclopedia Britannica. Encyclopedia Britannica. 7. Encyclopedia Britannica, may 12, 2006. web. 3/4/14. http://www.britannica.com/topic/362098/history From this article i am obtaining information pertaining to the scientists who started the manhattan project and what the project accomplished. 3.Henry Lewis Stimson. columbia. 1.Columbia University in New York, letter. 3/3/2014. http://www.atomicarchive.com/Docs/MED/med_chp10.shtml august 6, 1945 a special b-29 called enola gay dropped the first atomic bomb ever on hiroshima. the government censored reports coming from hiroshima coming to america. 4.(Hitoshi Takayama). atomic bomb museum. 1. Hiroshima Peace Memorial Museum, 2006. Medium of publication. 3/3/14. . http://atomicbombmuseum.org/index.shtml 5. n.e. atomic archive. 1. AJ Software Multimedia , N.d. web. 3/4/14.5. This source give information about treaties after the bomb and the destructive effects it had on the world. http://www.atomicarchive.com/Docs/MED/med_chp10.shtml This is a secondary source. I am gathering information about the casualty number, cause of death, and mortality rate. 7. ushistory.org. ushistory.org. 1. 2014). web page. 3/3/2104 http://www.ushistory.org/us/51g.asp America was very weary of the war by the time the atomic bomb was finished. The allies first asked the japanese for surrender, but without mention of a new or very devastating bomb. after the 2 bombs were dropped the japanese surrendered 5 days after.

Digital Communication Simulation Using Matlab Computer Science Essay

Digital Communication Simulation Using Matlab Computer Science Essay Objective Aim Scope of the assignment The objective of this assessment is to model and analyse modulation and coding in Communication Systems using Matlab.[1] This lab exercise aims to teach (show) modulation demodulation techniques like QAM 64 over AWGN wireless channel throw Matlabs Communication toolbox. In task 1, simulation and analysis of modulation and demodulation (using the 64-QAM) is been perform. By use of Matlabs high performance language, a designed code is been given in each task. Transmitted and received signals are been show in scatter plots at different SNR values. Simulation of the rectangular pulse shaping filter in combination with modulation is been introduced in the second part. The effect of rectangular pulse shaping is been used at the transmitter side after the QAM-64 modulation. Integrate and dump operation effect is been used at the receiver side. A full analysis of these two effects is been given below. In both tasks, the transmission is being over an AWGN (Additive White Gaussian Noise) wireless communication channel. Comparison, analysis and a discussion of the results is been given below each task. Introduction on general modulation/demodulation and 64-QAM AWGN channel, noise and rectangular pulse shaping Modulation Demodulation Modem In the area of telecommunications, modulation is the process of changing a periodic waveform (i.e. a tone), in order to use that signal to transfer a message. Normally the carrier signal (usually is a sinusoidal) has higher frequency than the input signal. Amplitude, phase and frequency are the three key parameters of a sine wave. These parameters can be modified in accordance with a low frequency information signal to obtain the modulated signal. Amplitude modulation (AM), frequency modulation (FM) and phase modulation are the most common analog modulation techniques. Radio and television broadcast stations typically use AM or FM. More complex forms of modulation are Phase Shift Keying (PSK), Amplitude Shift Keying (ASK) and Frequency Shift Keying (FSK) which are the three basic digital modulation techniques. A device that performs modulation is known as a modulator and a device that performs the inverse operation of modulation is known as a demodulator. A modulator converts a digital signal to an analog signal (typically a sinusoidal signal) and a demodulator converts a modulated (analog) signal back to the original unmodulated (digital) signal.[2] A few years ago a computer was connected to the internet through a modem (in now days a different type is being used, ADSL modem/router) over a regular analog line. A modem converts an outgoing digital signal to an outgoing modulated signal, and converts an incoming modulated signal to an incoming digital signal.[2] Modulation is used to change the signals bandwidth so it can be transmitted on a limited-bandwidth communication channel (like a telephone line or a cable TV channel) without too much distortion.[2] It also allows more connected users on the same communication link. Digital modulation Digital modulation schemes transform digital signals into waveforms that are compatible with the nature of the communications channel. There are two major categories of digital modulation. One category uses a constant amplitude carrier and the other carries the information in phase or frequency variations (FSK, PSK). The other category conveys the information in carrier amplitude variations and is known as amplitude shift keying (ASK). In digital communications, modulation is often expressed in terms of I and Q. This is a rectangular representation of the polar diagram. On a polar diagram, the I axis lies on the zero degree phase reference, and the Q axis is rotated by 90 degrees. The signal vectors projection onto the I axis is its I component and the projection onto the Q axis is its Q component.[5] Figure 1 I-Q format [5] Figure 2 Trends in the industry [5] Main Digital Modulation Schemes Techniques Amplitude Shift Keying (ASK) Amplitude shift keying represents digital data as variations in the amplitude of a carrier wave. There is an on/off transmission that represents the binary logic 1/0. ASK has poor performance cause is heavily affected by noise and interference. For binary digital modulation, BASK is the simpler form of ASK. Figure 3 Amplitude Shift Keying (ASK) [3] Frequency Shift Keying (FSK) The carriers frequency is modulated by the digital signal. 1/0 represented by two different frequencies slightly offset from carrier frequency.[4] That means that is a different frequency for 1 and another frequency for 0. FSK can be expanded to a M-ary scheme, employing multiple frequencies as different states.[3] For binary digital modulation BFSK is the simpler form of FSK. Figure 4 Frequency Shift Keying (FSK) [3] Phase Shift Keying (PSK) Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing, or modulating, the phase of the carrier wave. Phases are separated by 180o. Phase modulation can be achieved simply by defining a relative phase shift from the carrier, usually equi-distant for each required state. Therefore a two level phase modulated system, such as Binary Phase Shift Keying, has two relative phase shifts from the carrier, + or 90o. Phase modulation requires coherent generation and as such if an IQ modulation technique is employed this filtering can be performed at baseband. [6] Figure 5 Phases separated by 180o on BPSK [4] Figure 6 Phase Shift Keying (PSK) [3] Multi-Symbol Signalling M-ary Signals Multiple-symbol signaling is the process where multiple levels are used to encode binary information into groups of two bite, four bits, etc. [8] Figure 7 M-ary signals [3] Amplitude and phase shift keying can be combined to transmit several bits per symbol (in the above figure M=4). These modulation schemes are often refered to as linear, as they require linear amplification. 16-QAM has the largest distance between points, but requires very linear amplification. 16PSK has less stringent linearity requirements, but has less spacing between constellation points, and is therefore more affected by noise. M-ary schemes are more bandwidth efficient, but more susceptible to noise. [3] Quadrature Phase Shift Key Modulation (QPSK) Quadrauture Phase Shift Keying is a form of PSK. QPSK is a system of modulating digital signals onto a radio-frequency carrier signal using four phase states to code two digital bits. QPSK is effectively two independent BPSK systems (I and Q), and therefore exhibits the same performance but twice the bandwidth efficiency. QPSK can be filtered using raised cosine filters to achieve excellent out of band suppression. Large envelope variations occur during phase transitions, thus requiring linear amplification. [3] Figure 8 QPSK [4] Quadrature amplitude modulation (QAM) Quadrature amplitude modulation is a combination of amplitude modulation and phase shift keying. It is a modulation scheme-technique which conveys data by modulating the amplitude of two carrier waves. That is an amplitude modulation on both quadrature carriers. These two waves, usually sinusoids, are out of phase with each other by 90Â ° and are that is why they called quadrature carriers. QAM has extensive use in digital microwave radio links. The 16-QAM below stands for 2n discrete levelsÆ’Â   n=2 same as in the above QPSK. Figure 9 16-QAM Figure 10 16-QAM [7] Additive White Gaussian Noise (AWGN) Additive means that the sum of the transmitted signal and noise produce the received signal. White means that its two sided power spectral density is flat for all frequencies of interest for radio communication system. The amplitude of the noise is distributed according to a normal or Gaussian distribution. [8] Its information gives a single impairment. Noise pulse shaping and rectangular pulse shaping In digital telecommunications, pulse shaping can be used to change the waveform of transmitted pulses, so the signal bandwidth matches that of the communication channel, reducing distortion and intersymbol interference. In other words its purpose is to make the transmitted signal suit better to the communication channel by limiting the effective bandwidth of the transmission. Modulation is often followed by pulse shaping. Rectangular pulse shaping repeats each output from the modulator a fixed number of times to create an up-sampled signal. Rectangular pulse shaping can be a first step or an exploratory step in algorithm development, though it is less realistic than other kinds of pulse shaping. If the transmitter up-samples the modulated signal, then the receiver should down-sample the received signal before demodulating. The integrate and dump operation is one way to down-sample the received signal. [8] Demodulation is often preceded by a filtering or an intergrate and dump-operation. Answers to assignments tasks Task 1 In this assignment you are required to design and implement the process of modulating a random binary data stream using 64-level QAM (quadrature amplitude modulation), transmitting it over an AWGN (Additive White Gaussian Noise) wireless communication channel, and demodulating the received signal using the 64- QAM demodulator. Your system should consist of a baseband modulator, AWGN channel, and a demodulator. The following table indicates some relevant functions from the Matlab Communications Toolbox which may be used in this assignment. The functions for 64-QAM modulator/demodulator can be taken from the Matlab Communications Toolbox, or even implemented by you. Job Function Generate a random binary data stream randint Add white Gaussian noise awgn Create a scatter plot scatterplot Compute the systems BER biterr The length of the binary data stream (i.e., the number of the rows in the column vector) is set to 5000. Task 1.1 Write codes to 1) Display the transmitted and received signals in different scatter plots for the following two situations: a) SNR = 40 dB; b) SNR = 14dB; 2) Compute the systems bit error rate (BER) for the two situations. Answer 1.1 1a) The m-file for SNR=40dB x=randint(4998,1); %Random binary data stream of 4998 digits %Bits to symbols mapping xsymbols=bi2de(reshape(x,6,length(x)/6).,left-msb); y=qammod(xsymbols,64); %Modulation using the 64-QAM yTx=y; %Transmitted signal scatterplot(yTx) grid; title(Transmitted Signal) %Transmission over an Additive White Gaussian Noise channel,SNR=40dB ynoise=awgn(yTx,40,measured); yRx=ynoise; %Received signal scatterplot(yRx) grid; title(Received Signal, SNR=40dB) zsymbols=qamdemod(yRx,64); %Demodulation using the 64-QAM z=de2bi(zsymbols,left-msb); %Symbols to bits mapping z=reshape(z.,prod(size(z)),1); %Computation of Number of Erros and Bit Error Rate [Number_of_errors,Bit_Error_Rate]=biterr(x,z) Figure 11 Transmitted signal Figure 12 Received signal 1b) The m-file for SNR=14dB x=randint(4998,1); %Random binary data stream of 4998 digits %Bits to symbols mapping xsymbols=bi2de(reshape(x,6,length(x)/6).,left-msb); y=qammod(xsymbols,64); %Modulation using the 64-QAM yTx=y; %Transmitted signal scatterplot(yTx) grid; title(Transmitted Signal) %Transmission over an Additive White Gaussian Noise channel,SNR=40dB ynoise=awgn(yTx,14,measured); yRx=ynoise; %Received signal scatterplot(yRx) grid; title(Received Signal, SNR=14dB) zsymbols=qamdemod(yRx,64); %Demodulation using the 64-QAM z=de2bi(zsymbols,left-msb); %Symbols to bits mapping z=reshape(z.,prod(size(z)),1); %Computation of Number of Erros and Bit Error Rate [Number_of_errors,Bit_Error_Rate]=biterr(x,z) Figure 13 Transmitted signal Figure 14 Received signal 2) Computation of the systems bit error rate for the two situations SNR=40dB SNR=14dB Task 1.2 Compare/explain in detail the results obtained in a) and b), and explain clearly how the differences come from. Answer 1.2 In the above code, there is a bit to symbol mapping. A bit cant take values from 0-63 but a group of bits can. The two transmitted signals are identical cause both signals modulated with the same modulation schemes (64-QAM) and transmitted throw the same channel (Additive White Gaussian Noise wireless channel). Received signals have different scatter plot. This happens cause the first received signal was transmitted throw a channel with SNR=40dB and the other one was transmitted throw a channel with SNR=14dB. In the second scatter plot it is obvious that the channel is too noisy in accordance with the first scatter plot which seems that it hasnt got any clue of noise. For example, if a ADSL line has SNR lower than 15dB then several problems occurred like frequent disconnections etc. According to scatter plots the bit error rate and the number of errors for the first signal with SNR=40 was expected to be 0 cause the channel was clear from noise. On the contrary, for the second signal with SNR=14dB bit error rate and number of errors expected to be non zero. Both expectations verified. The ratio of the signal strength to the noise level is called the signal to- noise ratio (SNR), . If the SNR is high (ie. the signal power is much greater than the noise power) few errors will occur. However, as the SNR reduces, the noise may cause symbols to be demodulated incorrectly, and errors will occur. [3] Task 2 Modulation is often followed by pulse shaping, and demodulation is often preceded by a filtering or an integrate-and-dump operation. In this task you are required to investigate the effect of rectangular pulse shaping by using it at the transmitter side after the 64-QAM modulation and also the effect of integrate-and-dump operation at the receiver side. Rectangular pulse shaping repeats each output from the modulator a fixed number of times to create an upsampled signal. If the transmitter upsamples the modulated signal, then the receiver should downsample the received signal before demodulation. The integrate-and-dump operation is one way to downsample the received signal. The following table indicates the additional relevant functions from the Matlab Communications Toolbox which may be used in this assignment. Job Function Rectangular pulse shaping rectpulse Intergrate-and-dump downsampling Intdump Task 2.1 Write codes to 1) Display the received signals in scatter plots when a) SNR = 40 dB; b) SNR = 14dB; 2) Compute the systems bit error rate (BER) for the two situations. Answer 2.1 1a) The m-file for SNR=40dB %Random binary data stream of 5004 digits x = randint(5004,1); %Bit to Symbol Mapping xsymbols = bi2de(reshape(x,6,length(x)/6).,left-msb); %Modulation using the 64-QAM. y = qammod(xsymbols,64); %Pulse shaping, 3 samples per symbol shaped=rectpulse(y,6); %Transmitted Signal yTx = shaped; scatterplot(yTx) title(Transmitted signal) grid; %Transmission over an Additive White Gaussian Noise channel,SNR=14dB ynoise = awgn(yTx,40,measured); %Received Signal yRx = ynoise ; %Integrate and dump deshaped=intdump(yRx,6); scatterplot(deshaped) title(Received signal,SRN=40dB) grid; %Demodulation using the 64-QAM zsymbols = qamdemod(deshaped,64); %Symbol to bit mapping > to perform the computation of BER z = de2bi(zsymbols,left-msb); a = reshape(z.,prod(size(z)),1); %Computation of Number of Erros and Bit Error Rate [Number_of_errors,Bit_Error_Rate] = biterr(x,a) Figure 15 Received signal,SNR=40dB 1b) The m-file for SNR=14dB %Random binary data stream of 5004 digits x = randint(5004,1); %Bit to Symbol Mapping xsymbols = bi2de(reshape(x,6,length(x)/6).,left-msb); %Modulation using the 64-QAM. y = qammod(xsymbols,64); %Pulse shaping, 3 samples per symbol shaped=rectpulse(y,6); %Transmitted Signal yTx = shaped; scatterplot(yTx) title(Transmitted signal) grid; %Transmission over an Additive White Gaussian Noise channel,SNR=14dB ynoise = awgn(yTx,14,measured); %Received Signal yRx = ynoise ; %Integrate and dump deshaped=intdump(yRx,6); scatterplot(deshaped) title(Received signal,SRN=14dB) grid; %Demodulation using the 64-QAM zsymbols = qamdemod(deshaped,64); %Symbol to bit mapping > to perform the computation of BER z = de2bi(zsymbols,left-msb); a = reshape(z.,prod(size(z)),1); %Computation of Number of Erros and Bit Error Rate [Number_of_errors,Bit_Error_Rate] = biterr(x,a) Figure 16 Received signal,SNR=14dB 2) Computation of the systems bit error rate for the two situations SNR=40dB SNR=14dB Task 2.2 Compare/explain the results with those obtained in Task 1, and explain clearly how the differences come from. Answer 2.2 The difference between Task1 and Task 2 are the rectangular pulse shaping and integrate and dump operation. Rectangular pulse shape upsampling the signal after modulation. It actually applies a square pulse to the signal and repeats each symbol several times (in this case symbols are repeated 6 times). The dump operation is downsampling the signal. It is actually an integral of the signal for a single period. In this case, modulation followed by pulse shaping and demodulation preceded by integrate and dump operation. Since rectangular pulse shaping repeats each output from the modulator a fixed number of times then we expected our signals to be better than those in task1. This expectation came true since BER for SNR=40 dB is 0 and for SNR=14 dB is 0.0038. In the second case when SNR=14 dB it is obvious that BER and number of errors reduced dramatically. The filtering on the transmitter causes intersymbol interference. The filtering at the transmitter and the channel typically cause the received pulse sequence to suffer from interysmbol interference and this appear as an amorphous smeared signal, not quite ready for sampling and detection. When the channel bandwidth is much greater than the pulse bandwidth, the spreading of the pulse will be slight. When the channel bandwidth is close to the signal bandwidth, the spreading will exceed symbol duration and cause signal pulses to overlap. This overlapping is called intersymbol interference. [11] Rectangular pulse shaping was used to minimize distortion and the effect of intersymbol interference. It made the transmitted signal fit better to the communication channel by limiting the effective bandwidth of the transmission. The BER and number of errors improvement succeeded because symbols were sent several times. In this case, filtering made the signal better. Without filtering, signals would have very fast transitions between states and therefore very wide frequency spectra much wider than is needed for the purpose of sending information. [5] Conclusions If the SRN value is high enough, the received signal is almost clear from noise. High SNR value stands for a value close to zero for Bit Error Rate. In the presence of noise and interference, it is necessary to increase signal power to reduce the possibility of errors. The bit error rate (BER) of a system indicates the quality of the link. Filtering is essential for good bandwidth efficiency. High level M-array schemes (such as 64-QAM) are very bandwidth-efficient but more susceptible to noise and require linear amplification. [3]

The Peloponnesian War :: essays research papers fc

The Peloponnesian War Is war inevitable? It appears that the answer to this question is yes. However, war is unpredictable and must be studied based on individual circumstances, actions taken, and reactions. States disagree with each other on many subjects and conflicts arise often. To answer this question, we must first examine the causes of a conflict, evaluate the outcome and determine any alternatives that may exist. Then we can analyze some alternative theoretical outcomes compared to the actual conclusions. The Peloponnesian War provides an excellent example to be evaluated. The following gives a brief history of the war, causes of the war, and the importance of its study. In the case of the Peloponnesian War, we have two equal but different powers in control of Greece and the surrounding area. Athens and Sparta as allies gained independence from the Persians in 480 BC. Athens with a democratic rule expanded by using the surrounding waterways for trade and developing a great navy. Sparta with an oligarchic rule settled in by developing a thriving agriculture community and a land based army. Civil war occurs in Epidamnus with two sides, democratic and oligarchic. The democrats requested assistance from Athens. If Athens chooses to get involved, she breaks the truce with Sparta. If she does not, the balance of power leans towards Sparta and her allies. Sparta already feared Athens’ growing power. Therefore, Sparta needed to check Athens’ control of the region. The need to keep a balance of power is the main reason of the Peloponnesian War. Thucydides attains that Sparta’s fear of Athenian rule provided an unavoidable path to war. Athens controlled about half of the city-states; dominated much of the trade; and maintained a strong navy. Sparta kept a strong army and retained equal allies but was primarily an agriculture state. Athens’ ability to maneuver on the sea provided opportunities to expand her power, and this alarmed Sparta. Since Sparta is concerned by Athens’ growing power, Sparta waits for a way to be able to stop the expansion. When an opportunity comes for war against Athens, Sparta is not very reluctant and could even be considered eager to enter an altercation. Pericles leadership appeared sound but may have over reached the power of Athens. Pericles convinced the Athenians that allowing allied states to become free was a sign of weakness. In addition, he convinced them that Sparta was no match and could not win a long-term war against the great Athenian navy.

The Scarlet Letter: The Use Of Hester :: essays research papers

In The Scarlet Letter, Nathaniel Hawthorne makes Hester Prynne the central figure in the story much like Susanna Rowson does with Charlotte in Charlotte Temple. The plots of the books are centered on these women; the storylines occasionally move elsewhere to inform the reader of the happenings of other characters, but always returns to their respective female protagonist. The authors’ use of their leading ladies differs when providing a theme, however.Susanna Rowson uses Charlotte Temple as an example for the reader. By taking the reader on a journey through Charlotte’s life of perpetual misery, Rowson’s narrator is able to point out where Charlotte makes poor decisions. With the reader now aware of the misdirected choices of Charlotte, the narrator warns the reader that any young girl could end up in the same type of predicament. She then teaches the young female reader how she should react in a similar situation and the â€Å"sober matron† reader how to prevent such a dilemma from happening to her daughter. In summary, Charlotte Temple’s actions are used to directly teach the theme as Rowson wishes.Nathaniel Hawthorne uses his main character in a completely different way. It is common for a reader of The Scarlet Letter to determine that the theme of the story is that adultery is bad, but that is not the case. Hawthorne is not promoting adultery; that is true: As Darrel Abel states in his essay, â€Å"Hawthorne’s Hester,† â€Å"Although we are expected to love and pity Hester, we are not invited to condone her fault or to construe it as a virtue.†1 Hester Prynne and her lecherous sin are Hawthorne’s means of conveying a different message; Hawthorne is more interested in uncovering the flaws of puritan society and the hypocrisy of their reactions to Hester. The character of Hester Prynne is created as to exploit these flaws indirectly.The Puritan culture is one that recognizes Protestantism, a sect of Christianity. Though a staple of Christianity is forg iveness for one’s sins, this has long been forgotten amongst the women of Boston: â€Å"Morally, as well as materially, there was a coarser fibre in those wives and maidens of old English birth and breeding, than in their fair decendants.†2 When Hester is first brought out of her prison cell, the gossiping goodwives recommend much harsher punishments, from a brand on her forehead to death. Hester, who had done little wrong prior to this sin of adultery, is no longer seen as a human being, but merely as a symbol of evil and shame upon the town.

Captains of Industry :: essays research papers

In 1796, president George Washigton wrote a farewell address to speak to the nation before he retired. In this, he explained valid reasons to keep America an isolated as well as neutral country. It is clearly prominent that Washington's farewell adress was necessary. This is due to the fact that it gave the nation something to ponder as well as dwell upon. Washington's intent was for his adress was to serve as an itenerary for the future of our nation. This did not succeed. Although it would be reasonable to be used today, we continue to remain allies with some countries, and enemies with others. Washington's address analyzed the nation's domestic difficulties. He stated that, "...anthipathies against particular nations and passionate attachments for others should be excluded, and that, in place of them, just and amicable feelings toward one another should be cultivated." In this, he expressed his desire for neutrality in the nation. Another main point that explains the necessity of the address was to cement the fact that we should stay out of other country's affairs; that we should be our own independant nation. Washington did not want America to take sides, because at that time, America was stilll forming as its own country and he believed that we should concentrate on our country. If America is to be an independant country, why should we have affairs with other countries? For example, Europe. Washington strongly felt that we should break ties and establish none with other foreign contries and that we should not, at any circumstance, interfere with European affairs. In his reasoning, he expressed his desire for isolation in the nation. Being a strong figure that many looked upon, Washington's intent for his policy of isolation and neutrality was to serve as a prescription for future years. By using VALID reasoning combined with hope for his nation, Washington denounced the idea of favorites and enemies in order to for our nation to be "a free, enlightened, and, at no distant period, a great nation to give mankind the maganimous and too novel example of a people always guided by exhalted justice and benevolence..." His speech was also addressed at the end of term, in order to serve as a basis for the future of our country to follow. Despite this GRATUITUS attempt, his address did not succeed in being the precedent it was designed to.