Limitations of Self-Report Data free essay sample

Limitations of Self Report Data Abstract Self-report data may be obtained from a test or an interview format of a self-report study. The format of self-report study that will be used to discuss limitations of self-report data will be a test and a personality disorder test will be used as an example. For specific example answers for the test I completed the results all rated â€Å"low† for all personality disorders. Limitations arise from decreased reliability and validity and issues with credibility of responses due to response bias. Content validity, construct validity and criterion-related validity as well as test-retest reliability will be presented. The forms of response biases that will be discussed are social desirability, acquiescence, halo effect, extreme responding, midpoint responding, random responding, negative/positive bias, memory recall bias and cultural bias. The discussion will conclude with the role self-report data plays in psychology today. Limitations of Self-Report Data Self-report data has the advantage that they come directly from the test taker themselves and not from a third party; who would know someone better than themselves? Self-report studies can examine a large number of variables such as feelings, behaviours, attitudes and beliefs. They are easy to administer, inexpensive and most take a modest amount of time to complete (McDonald, 2008). Self-report tests are able to assess matters that are not observable such as feelings, beliefs and opinions. The scoring of self-report tests is standardized whether it be a scoring template for pen and pencil formats or computer-based interpretations for tests whose answers are entered into a data file (Hood Johnson, 2007). However, it does have some limitations. The validity of causal conclusions drawn from self-report data may be of concern because it can be influenced by factors such as the psychometric properties (validity and reliability) of the test, the context (environment/situation) of the test, and response biases (Dodd-McCue Tartaglia, 2010). . Validity Content Validity Content validity is the extent to which a test is measuring the domain it is supposed to be measuring (Hood Johnson). Meaning for example; does the 4degreez. com Personality Disorder Test measure for personality disorders? Computers allow for much more complex self-report test scoring, and are accurate and thorough. A test’s construction can also play a key role. The content validity of some tests relies on the appropriate qualifications and level of expertise of the designers of the test and of the database used for computer-based test interpretations (Hood Johnson). For the 4degreez. com Personality Disorder Test the designers decide what questions to include in order to identify the different features of personality disorders. The creators of the database decide which answers correlate with a personality disorder. For self-report testing the fundamental way a question is worded can influence a person’s interpretation and thus their response. In the 4degreez. com Personality Disorder Test this may lead to the erroneous detection of the presence or no presence of diagnostic criteria. For example in the: Q1 â€Å"Do you believe you have more difficulty with relationships than the average person your age? † (4degreez. com, n. d. , p. 1). I didn’t know how to interpret or answer this question; do they mean social relationships or intimate relationships? Had I understood it as both and answered â€Å"yes† my answer would have been measured as a diagnostic criteria for Schizoid Personality Disorder. When I completed the test I answered â€Å"no† because neither situation applied for myself. There was no information given in regards to the designers of the 4degreez. com Personality Disorder Test nor for the database used for the computer-based test interpretations used to score the test; therefore it is unknown on how it faired for content validity. In addition it is questionable whether the number of questions (#71, excluding â€Å"What sex are you? †) were adequate to accurately assess the presence of a personality disorder. Construct Validity Construct validity is the extent to which a test measures a theoretical construct (Dyce, n. d. ); that is, can the 4degreez. com Personality Disorder Test measure the presence of the different behaviours described by the diagnostic criteria for the different personality disorders? There are two subcategories of construct validity: convergent validity and discriminant validity. In the case of a personality disorder test convergent validity is the degree to which the test that should be theoretically related to a behaviour associated with a given personality disorder is in fact related. This form of validity is an example in which results should be taken in a person’s context or in conjunction with results of other forms of testing. For example, Q11 of the 4degreez. com Personality Disorder Test (n. d. ) â€Å"Do you have a difficult time relating to others? † (p. 1). If a person’s contacts are of at a lower education level their language or ideas may or may not be understood. For discriminant validity it is the degree to which the test that should not be theoretically related to a behaviour associated with a given personality disorder is in fact not related. No information was available to know how the 4degreez. com Personality Disorder Test faired on testing for construct validity. Howard (1994) claims that the construct validity coefficients of self-report testing are superior to those of other forms of testing. Criterion-Related Validity As Dyce (n. d. ) explained criterion-related validity is the relationship between the test score and a criterion measure such as a behaviour. In the 4degreez. com Personality Disorder Test responders may think they possess a great deal of self-knowledge when in fact they may not therefore their answers may not accurately reflect their behaviours. Concurrent criterion-related validity is when the test score and the criterion are measured at approximately the same time. Predictive criterion-related validity is when the criterion measure is collected after the test score is collected. When self-deceptive socially desirable responding (SDR) in self-report testing, as defined in the social desirability subheading below, is controlled the predictive criterion-related validity is reduced therefore this form of SDR should not be controlled (Paulhus, 1991). Reliability Test-Rest Reliability Test-retest reliability compares the results of two of the same tests taken at different times (Dyce, n. d. ). A person’s state of mind and conditions of he environment may influence responses. The length of time between which the tests are taken should be recorded so it can be taken into account when interpreting the reliability coefficient. Changes in environmental conditions (e. g. , temperature, noise level, or lighting) or state of mind can all affect test-retest reliability. I performed the 4degreez. com Personality Disorder Test on two separate days. The f irst time it was completed all ten personality disorders were rated â€Å"low†; whereas the second time one was rated â€Å"high†, two were rated â€Å"moderate†, and the other seven were rated â€Å"low†. Thus on this occasion the 4degreez. com Personality Disorder Test was not very test-retest reliable. This may be attributed to poor sleep the night before and not haven eaten yet, therefore I was a bit irritable. In addition students like myself, who have high cognitive demands, may take mental shortcuts in completing the test depending which will thus decrease reliability. Response Bias Social Desirability Socially desirable responding (SDR) is when a person answers questions in such a way that they â€Å"look good† to others. Such responses will obviously skew results. The issue of SDR in measuring personality, psychopathology, attitudes and sensitive behaviours has been of concern for over sixty years (Paulhus). Subsequently, various methods of measuring (but not controlling) SDR were developed. The â€Å"Lie scale† used in the MMPI to detect obvious dishonesty is an example of one such method (McDonald). Self-report tests such as personality disorder tests rely heavily on the honesty of the responder; however SDR may be done consciously or unconsciously. Another form of SDR is: 1) self-deceptive positivity which is an honest but overly positive self-presentation which is linked to a MMPI factor and 2) impression management which is a conscious and purposeful positive self-presentation (Paulhus). SDR is more likely to occur with questions that address personal issues such as beliefs and integrity. Many of the questions in the 4degreez. com Personality Disorder Test were laden with vulnerability for SDR; for example, Q21 â€Å"Do you sometimes profit at the expense of others, without being bothered by pain or damage you may cause them? (p. 1). It would take a lot of trust and honesty for a person to answer â€Å"yes† if it was in fact true. Computer based self-report testing helps reduce SDR because there is more sense of anonymity. Using ipsative (forced choice; e. g. , yes/no, agree/disagree or true/false) questions in self-report testing also helps reduce SDR. Had I completed the 4degreez. com Personality Disorder Test a cou ple years back I would most probably have been influenced by this type of response bias; however â€Å"looking good† is no longer of importance to me. When I completed the 4degreez. om Personality Disorder Test I did so honestly and truthfully so as the results would be accurate. Acquiescence Acquiescence is a response style dubbed â€Å"yea-saying† which is the tendency to answer â€Å"yes† or agree irrespective of the content of the question. One explanation for acquiescence lies in the personality trait of the responder associated with impulsiveness (Dodd-McCue Tartaglia). â€Å"Yes† answers are more likely when the question is ambiguous, neutral in desirability or vague (Dodd-McCue Tartaglia) and the responder is uncertain on how to answer. Most tests are now designed with evenly distributed negatively and positively worded questions, in order to maintain reliability. This form of balancing only controls â€Å"agreement acquiescence† (agreeing with similar types of questions) and not sufficient for â€Å"acceptance acquiescence† (agreeing with all questions irrespective of type) (Paulhus). On examination of the 71 questions in the 4degreez. com Personality Disorder Test it was concluded that the majority were negatively worded, thus it appears that appropriately balanced wording of questions was not incorporated.

Types of Diseases, Treatment and Their Control Methods free essay sample

A disease is an abnormal condition affecting the body of an organism. There are four main types of disease: pathogenic disease, deficiency disease, hereditary disease, and physiological disease. Pathogenic diseases are caused by what is called a pathogen. Pathogens are parasitic organisms that cause disease in their host. For example the pathogen e. coli which can make people ill or kill them. Deficiency diseases are caused by a deficiency of a particular nutrient in the diet. A lack of vitamin c causes scurvy. Hereditary diseases are passed on through generations via their genes, for example sickle cell disease. Physiological diseases are caused by the failure or malfunction of body parts or organs, for example diabetes. Proper sanitation and other disease-avoidance measures, ranging from hand washing to vaccination, as well as taking antibiotics are used in the prevention and treatment of pathogenic diseases. Hereditary diseases are treated by enzyme replacement therapy, medication miglustat, and bone marrow transplantation and gene therapy1 Physiological diseases such as diabetes can be treated by: Diet- a healthy diet is key to controlling blood sugar levels and preventing diabetes complications. We will write a custom essay sample on Types of Diseases, Treatment and Their Control Methods or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Exercise-regular exercise can reduce the risk of developing complications of diabetes such as stroke and kidney failure. Hypertension can be treated by: Diet- eating foods low in sugar, starch and salt. Exercise- a regular exercise program may help lower blood pressure over the long term. Bibliography †¢www. Blurtit. com †¢www. Wikipedia. com †¢www. ehow. com †¢ L. Chinnery, J. Glasgow, G. Jones and M. Jones (2001). CXC Biology Third Edition. Cambridge University Press

Pilgrimage essays

Pilgrimage essays As early as the 4th century A.D. pilgrimage started developing. This first started occur after Emperor Constantine legalizes Christianity. As Christianity was already legally spreading it gained many followers who wanted to gain purification in their souls and salvation by going to holly places such as Jerusalem. Pilgrimage is in a way a journey to a Spiritual transformation expressed in an act of homage to the deity and its early representatives involving travel to a holy site. Most of the places where people would go to a pilgrimage such as Canterbury (St. Theodores bones) in England or Santiago de Compostela (St. James bones) in Spain are connected with relics. This is a physical object with sacred meaning. What was so sacred? It was an example of the contact of the mental world with the transcendent. It was an example of reincarnation of Christ. Physical healing was a major reason for people to go to a pilgrimage. The Pilgrimage changed its form with the centuries. At the 11-13th centuries the Crusades were called pilgrimage. The world crusade wasnt used. During the 12-16th centuries pilgrimage was sort of remission of penance. It was to clear one from ones mistakes. The fact that one has already prepared and is on his way to a pilgrimage meant that he is already forgiven for his deeds. Pilgrimage helped not just for spiritual transformation but also for economic growth for the land that was visited by the pilgrims. Also, pilgrimage helped for better geographical understanding of foreign countries and even for the creation of maps. It was very useful for people from one side of the world to understand the culture, the art, music and architecture of people from the other side of the world. It was very important that during pilgrimage people would do some trade even sometimes souvenirs. ...

Global Law Essay Example | Topics and Well Written Essays - 2500 words

Global Law - Essay Example Her inner thighs, buttocks, perineum, genital areas and groin were severely burned that she had to be admitted for treatment to the hospital for 8 days. While in the hospital for treatment, Liebeck went through skin grafting and debridement treatments. Liebeck filled a claim with McDonalds for $20,000.00, but McDonald refused to pay the said amount so Liebeck brought the case to court. During the discovery proceedings, McDonalds produced documents showing more than 700 claims by people burned by its coffee between 1982 and 1992 and a number of these claims were similar to that of Liebeck. The documents presented by McDonalds proved that McDonalds knows about the hazards that its coffee products have on drive-thru costumers. McDonalds’ quality assurance manager also said that based on the advice of its consultants, the company made it a policy to keep its coffee between 180 and 190 degrees Fahrenheit to keep its taste. This policy stands even though other companies serve their coffee lower temperature and coffee is normally served at home around 135 to 140 degrees. McDonalds’ quality assurance manager admitted that the company did not evaluate the safety ramifications that this practice may have on the costumers. He also acknowledged the fact that any food items served as 140 degrees or more may cause burning. He also acknowledged the fact that since McDonalds’ coffee is between 180 and 190 degrees, the coffee is not fit for consumption as it would cause burning on the mount and throat. 2. Issues to be decided by the court a. Whether or not Liebeck is entitled to compensation for the pains and sufferings that she went through after she was burned by the coffee bought from McDonalds. b. Whether or not McDonalds observed proper safety measures to protect its clients from possible harm that its products may cause. 3. Facts Relied Upon by Stella In arguing her case in court, Liebeck relied on the testimonies of a scholar in thermodynamics applie d to human skin burns. According to the expert, 180 degrees, liquids can cause third degree burns in a matter of two to seven seconds. The degree of the damage on human skin reduces exponentially as the temperature of the liquid reduces to 155 degrees and below. If Liebeck’s coffee had been around 155 degrees when it spilled on her lap, she may not suffer serious burns. 4. McDonald’s Defense McDonald claimed that its costumers buy coffee on their way to work or home with the intention of drinking the coffee once they arrive at their destination. As it is, the coffee would have enough time to cool down along the way so it will not be scalding hot when the costumers get to drink them. Another defense posed by McDonalds is that its costumers know that the coffee they buy from the drive-thru is hot and the costumers want it that way. 5. Court Decision The jury awarded Liebeck $200,000 in compensatory damages and another $2.7 million in punitive damages. The compensatory da mages were later on reduced by the jury to $160,000 since Liebeck was also at fault. The trial court, on the other hand, reduced the punitive damages to $480,000.00. 6. Opinion on the case Awarding both compensatory and punitive damages to Liebeck is only fitting in this case because McDonalds committed gross negligence in doing its job to protect its costumers. However, I do not agree with the jury’

Negotiations - hypothetical analysis Essay Example | Topics and Well Written Essays - 1000 words

Negotiations - hypothetical analysis - Essay Example It is back-and-forth communication designed to reach an agreement when you and the other side have some interests that are shared and others that are opposed.† Since there are two or more parties to a negotiation, the common belief is that one must win and the other has to lose. In this internet age, impacted by materialistic civilization, this approach will not hold good. The settlement arrived through good negotiations leads to a win-win situation, where all are winners. The author has articulated a simple and straightforward five-step system that covers the important aspect of negotiations and explains how to go about it in the practical world. The five concepts of negotiations chartered by Roger Fisher that I will put into practice to resolve the issue related to the three girl students (swimmers) are: 1. Don’t bargain over positions They call me "spineless" "heartless" "incompetent" and "lazy" in the third meeting. They also say "We've heard about you. We know that you got this job because two other school districts fired you for incompetence." I am not interested in contesting their claims. When an individual is angry, one says so many things which one actually doesn’t mean! By their verbal slangs, no damage is done to my approach and it is unlikely to change my working style. Try to understand the meanings of the words of their outburst. They have no connectivity. I will not argue with them on the issue for the present. Every argument has a counter argument, but that will not lead to solution. That two other school districts fired me for my incompetence is an incorrect statement. That they fired me is a fact; but that was due to differences as for my conciliatory approach to certain issues related to the students. That the management of the school where I am at present working is aware of the facts related to the cases, and yet they have appointed me as the Principal. They must be having their own reasons for having engaged me. My per spective of running the school administration meets with their approval. I do not believe in giving instant, harsh punishments to the students. I am supposed to look after an academic institution, not a military establishment, to take summary decisions. 2. Separate the people from the problem I would advise the parents of the bullied girl, to keep a low profile for the time being, in the overall interest of all concerned. This issue is going to be resolved, but not on their drastic terms. Expulsion is a serious step that leaves highly unpleasant consequences. It affects the future of the children, damages their psychology, and they may find it difficult to face the societal reactions. Expulsions are often challenged in the court of law, and an academic institution would like to avoid legal hassles, as far as possible. I love my student; she is like my daughter, as much as you love your daughter. Expulsion is the permanent black spot in the academic career of a student and it must be avoided at all costs. 3. Focus on interests, not positions My interest, as the Principal of the school, is to maintain the overall cordial atmosphere in the school, not the interest of just 2-3 students. I now propose to invite to the school the parents of the two students, who allegedly bullied the daughter of the parents who are the complainants. Bullying is a common trend amongst the students though, and in the present case jealousy, that the bullied girl is a superior swimmer is the root cause of the problem. I will also request the college swimming coach to counsel them individually and collectively, and if the feud is not ended immediately, their swimming career may be at stake and they will be removed from the college swimming team. So, along with the reputation of the college, their

Application of Wave Technology in Military Aspect

Application of Wave Technology in Military Aspect â€Å"Hide and Seek† in the World of Wave Student name: Choi Ho Lam Thank you for giving this valuable chance for me to investigate on this topic. As this topic involves military technology, it gives a deeper understanding of wave principle and usage in daily life. However, in normal settings, such kind of topic is not included, as it can be quite controversial. Fortunately, in this CCST course, I am allowed to choose this topic and enrich my engineering knowledge to a deeper extend. National geographic After watching the show â€Å"Hilter’s Stealth Fighter†, it gives me a clearer direction on starting the research on this topic. It enriches my knowledge on the use of RAM in relation with RF wave properties. Teaching assistants of the course The teaching assistants in the course are helpful. Their opinions help me to narrow my direction in investigating to specific topics like radar and specific technology related to radar. Without their help, I would still wonder in the wild world of military and aimlessly searching for a suitable topic. 2. Introduction Radar detection and stealth technology are like a game of â€Å"hide and seek† with the application of wave technology. They share the opposite aims, either finding one or avoid from being found. In the world of military, this is a game that changes the fate of the world and losing is not an option. During the World War II, the deployment of radar in British had changed the tide of battle in the English Channel. Fighting against 2550 German fighters and bombers, the Royal Air Force (RAF) was able to attack strategically and stopped German invasion with just 1963 planes. After this battle, British served as the last stand among European nations against Nazi Germany. With such important history, the military value for radar as well as its counterpart, stealth technology were deeply investigated. Nazi Germany had suffered from a direct defeat from this battle. Since then, Nazi Germany carried out various researches on stealth aircrafts. Just one month near the end of WWII, the first prototype stealth bomber, Horten Ho 229 was developed. Recent research from National Geographic show that such plane decreases the detection range of British radar by 37%, which is already enough for wiping out the entire RAF. It was so fortunate that the plane wasn’t in mass production or the course of history would have been change completely. This paper aims at studying the application of wave technology in the use of radar, as well as the principles in some of the counter radar measures. Since it is a CCST coursework, some of the complicated mathematical procedures and modern method of radar jamming would be omitted. Nevertheless, by studying such technology, we can establish a better understanding of different wave phenomena and know how they change our life. 3. Content 3.1 Radar Radar stands for Radio Detecting and Ranging. In general, radar detects a far object by sending a pulse of EM wave and measures the time and frequency for the reflected pulse. By analyzing these factors, the speed and the distance of the far object can be found. In a macroscopic view, radar consists of 3 basic parts, a transmitter, a duplexer and a receiver. The transmitter emits a short-duration high-power radio frequency (RF) pulse. The pulse will travel through the transmitter antenna and emit outwards. The antenna can give appreciate space for efficient distribution of RF pulse. When the RF pulse hit an obstacle, the RF pulse is reflected back to the receiver. The receiver antenna will receive the signal and analysis the time of travel as well as the frequency of reflected pulse. Since the receiver antenna is very sensitive as it is assumed to be receiving the small pulse reflected back from far distance, a duplexer is installed to switch the between two antenna. This can ensure only one antenna is in use and prevent receiver antenna receiving signal directly from the transmitter antenna, which can potentially damage the receiver antenna. In a microscopic view, an alternating current (AC) is supplied to the antenna. It then produces a perpendicular alternating magnetic field around the antenna. By Lenz’s Law, for a closed loop carrying a current, it would produce a magnetic field perpendicular to current around the loop. In reverse, for a closed loop experience a change in magnetic field, a current perpendicular to magnetic field is generated to oppose the change. The combination of alternating current and magnetic field produces the electromagnetic wave that used for detection. The frequency of the EM wave can be changed by modifying the AC frequency. The frequency of the electromagnetic wave is usually set to between 3 kHz to 300 GHz at radio frequency (RF). It varies depends on the usage. With a higher frequency, using relation with speed of light (C) and wavelength (ÃŽ ») C=FÃŽ », the wavelength of RF wave is shorten. This decreases the electrical length of the antenna to and makes it easier to build. In military use, the RF pulse would set to lower frequency portion in the RF spectrum, usually between 7 to 11.2 GHz, which is called the X band. Being in RF spectrum, the high frequency radar pulse can create a radar cross-section of aircraft with a higher resolution, which helps identify aircraft more accurately. In more advance use, a much lower frequency is used to reveal stealth aircraft since it can give a much more sensitive signal. With a low frequency, the wavelength of radar pulse is comparable to size of stealth fighter and creates a scattering in resonance region instead of optical region, turning it more visible on radar. However, the frequency of the radar pulse cannot be lower than 800 MHz, otherwise the EM pulse would have insufficient penetrating power and easily be absorbed by raindrops. Other than that, the resolution of low frequency radar is relatively poor, and gives a poor display. It is only effective against stealth aircraft of length comparable to wavelength . When the radar pulse is bound back to the radar, the antenna experience an alternating change in magnetic field. This will produce an alternating electrical field and thus an AC current to flow in circuit. Since the returning signal is weak, it would pass through an amplifying circuit to increase the amplitude. In analyzing the signal, the frequency and time of travel would be taken to find the speed and velocity of detection target. When the radar pulse reaches an object, it is reflected and the frequency is shifted by Doppler Effect. Since the speed of RF wave is always the speed of light (C), the distance (S) can be express as a time (t) function, S = Ct/2. It is divided by two since the radar pulse travel through the same distance twice. To calculate speed of moving object, we can find out the change in frequency (Doppler frequency) of the returning wave. If the far object is moving, the object would create a Doppler shift to the radar pulse. This Shifted frequency () can be expressed by original frequency (), the moving speed (V) and speed of light (C). , which gives us the Doppler frequency () . For convenience, one assume, such that, and simply the equation as . 3.2 Radar jamming and deception Radar jamming and deception usually refer to the intention of saturating the radar with noise and false information, lowering the detection range of radar as well as the accuracy of the radar. There mainly two types of jamming, either mechanical jamming or electronic jamming. Mechanical jamming Mechanical jamming usually refer to use of physically existed thing to reflect and re-reflect RF signal back to radar, causing the radar to be saturated with false return signal. The commonly used mechanical jamming methods that adopt wave principles are chaff and corner reflectors. Chaff is bundles of reflective aluminum strip of various lengths. The aircraft drops these strips in air. When radar pulse reaches these strips, the radar pulse is reflected and scattered in all direction, creating huge return signal to the receiver. This could deceive the radar as â€Å"seeing† huge plane and deplete enemy resources like ammunition on shooting down the false target. Corner reflector reflects incoming radar pulse at other angle. Corner reflector is composed of either two or three reflective planes, perpendicular to each other. This configuration allows the incoming radar ray fully reflected back to the source. Yet this also increases special occupation of corner reflector, making it harder to carry by aircraft. The tails of the stealth fighter are designed to be acute angle, such that it avoids forming corner reflector, allowing radar to identify the airplane. Electronic jamming Electronic jamming refers to the active emission of RF pulse to the radar, saturating the radar with false return and noises. It includes spot jamming, sweep jamming, barrage jamming, cover pulse jamming and digital radio frequency memory jamming. Spot jamming, sweep jamming, barrage jamming uses the same principle, occupying the radar with high energy pulse and causing destructive interference of the RF wave. Spot jamming refers to jamming one specific frequency with high energy signal. Sweep jamming refers to jamming one specific frequency with high energy signal when the radar is switching from one frequency to another. Barrage jamming refers to jamming all specific frequency with high energy signal, however since it cover full range of frequency, each frequency are partially jammed. Cover pulse jamming refers to false return signal as noise. As radar receives certain amount of ambient noise, for example, like scanning through eagle and other types of bird, so it could be used as disguise for fighter to hide from radar. With pulse jamming system installed, the aircraft analysis the incoming radar signal and find suitable frequency for false noise return. Digital radio frequency memory is a repeater technique that analysis the incoming radar pulse and changes the returning frequency as well as time of return. The signal would be delay and diminish. This gives a false sign of far distance between aircraft and radar. Moreover, the frequency would also be shifted and produce a false Doppler shift on radar signal. This returns with false information about the velocity of aircraft. 3.3 Use of RAM Besides of active jamming and deceiving radar, the military develop RAM to avoid radar detection from the enemy. RAM stands for the Radar-Absorbance Material. According to the detecting radar frequency, different types of RAM are used to build stealth aircrafts. Iron ball paint absorber Iron ball paint is one of the mostly used RAM. It contains tiny spheres coated with carbonyl iron and ferrite. As radar waves induce molecular oscillation in this paint, the energy would dissipate as heat. This can absorb the radar and reduce the reflection of radar wave. Re-entrant triangles The structures of re-entrant triangles in between the surface foam absorber layer help reduce reflection of radar ray back to radar transceiver. Inside the foam absorber layer, the foam was cut into tiny square pyramid. This structure reflect incoming wave several times and reduce the energy of the radar wave. In practice, the width and height would change according to the incoming radar wave. The main purpose of adjusting height and width ratio is to achieve maximum internal reflection within the plane surface as possible. Jaumann absorber The wave principle deployed by Jaumann absorber is destructive interference. Gerneally, Jaumann absorber consist of two equally spaced layer and a ground metal plate. It cancels out the incoming wave by producing destructive interference. When a radar signal strikes on to the surface of Jaumann absorber, the wave split in to two waves, one is reflected at glossy surface of the Jaumann absorber, while the other enters the layer. The ray will then reflect back by the metal ground plate. The two layers having a total spacing of ÃŽ »/4 will allow the wave reflected back to surface at anti-phrase compare to incoming ray, where the ray have travelled a total of ÃŽ »/2 distance. Conclusion Radar principle make use of various wave property in tracing the enemy. In engineering, there is a sub-discipline for radar analysis, for a more precise interpretation of radar signal. This paper includes only few example and it was just a corner of iceberg. However, in just a brief analysis, we can see advancement of technology as people know more about wave and using this knowledge to build stealth aircraft. This game of â€Å"hide and seek† can be devastating to world as it brings a much higher casualties in war, however this game has also proven to be saving life war and pushing the advancement of technology. Would this game be beneficial to human? It would be an unanswered question waiting for the people to decide. Reference Radar. (n.d.). Retrieved from http://en.wikipedia.org/wiki/Radar ODonnell, Robert. RES.LL-001 Introduction to Radar Systems, Spring 2007. (MIT OpenCourseWare: Massachusetts Institute of Technology), http://ocw.mit.edu/resources/res-ll-001-introduction-to-radar-systems-spring-2007 (Accessed 28 Nov, 2014). License: Creative Commons BY-NC-SA Wolff, C. (n.d.). Radar Principle. Retrieved from http://www.radartutorial.eu/01.basics/Radar Principle.en.html Toomay, J., Hannen, P. (2004). Radar Principle for the Non-Specialist (3rd ed.). SciTech Publishing. Hitlers Stealth Fighter [Motion picture]. (2009). United State of America: National Geographic. Garcia, L. (n.d.). How Waves Helped Win the War: Radar and sonar in WWII. Retrieved from http://www.ww2sci-tech.org/lessons/lesson3.pdf Deb, N.N. (2006). Telecommunication Engineering (1st ed.). New Age International. Bole, A., Wall, A., Norris, A. (2014). Radar and ARPA Manual Radar, AIS and Target Tracking for Marine Radar Users. Elsevier. Varshney, L. (2002). Technical Report Radar Principles (3rd revision.). NY: Syracuse Research Corporation. Lorell, M. (2003). The U.S. Combat Aircraft Industry, 1909-2000. National Defense Research Institute. Radar jamming and deception. (n.d.). Retrieved from http://en.wikipedia.org/wiki/Radar_jamming_and_deception Radar-absorbent material. (n.d.). Retrieved from http://en.wikipedia.org/wiki/Radar-absorbent_material Zikidis, K., Skondras, A., Tokas, C. (2014). Low Observable Principles, Stealth Aircraft and Anti-Stealth Technologies. Journal of Computations Modelling, Vol.4(No.1, 2014), 129-165. Retrieved from http://www.scienpress.com/Upload/JCM/Vol 4_1_9.pdf Stealth Technology. (n.d.). Retrieved from http://www.slideshare.net/search/slideshow?searchfrom=headerq=stealth technology

Privacy And The Internet Essay -- Web Cyberspace Internet papers

Privacy and the Internet The natural progression of the Internet and emerging technologies is towards streamlining our lives both personally and professionally. Instantaneous communications and available on-line services continue to reduce the physical distance between individuals. Almost anything is now available in cyberspace from shopping, schooling and education, on-line trading, banking, to social and political on-line communities. On-line service providers are shifting from a product centric approach to a more personal and customized approach to marketing their products and services. The idea of one-to-one marketing is very powerful and has become an important tool for competing in the interactive age. One-to-one marketing takes a customer-orientated approach to selling; customers are treated as individuals with different interests and needs. We respond positively to individual attention; when we visit a web site we want to see products and services of interest to us not every available product. We do not want to waste our time. For many people, time is money and the convenience factor ways heavily on the decision to return to a web site. Are the benefits of electronic communication at the expense of our privacy? How does the Internet affect the availability and use of our personal information? The Internet brings another dimension to the issue of privacy. Whether you are voting on-line or buying a book from Amazon.com you must consider how much personal information has been collected about you, with or without your consent, and how it can be used. Policies governing privacy on the Internet are still not clearly defined and many on-line users do not understand how the information they provide will be used. How much... ...activity are all available at the press of a button. Soon we will have on-line refrigerators that can place grocery orders, washing machines that can access the Internet to determine the best wash cycle for a delicate fabric and Internet connectivity available from every room in the house. If we reap the benefits of communications technology, we must expect to pay the price with our privacy. Works Cited Bridis, Ted. Comcast Tracks Users Web Browsing. Los Angeles Times 12 Feb 2002. http:www.latimes.com/news/nationworld/politics/wire/sns-ap-internet-privacy/0212feb12.story (25 Feb 2002). Grossman, Lawrence K. The Shape of the Electronic Republic. Composing Cyberspace. Richard Holeton. United States: McGraw-Hill, 1998, 311-327. Birkets, Sven. Into the Electronic Millennium. Composing Cyberspace. Richard Holeton. United States: McGraw-Hill, 1998, 311-327. Privacy And The Internet Essay -- Web Cyberspace Internet papers Privacy and the Internet The natural progression of the Internet and emerging technologies is towards streamlining our lives both personally and professionally. Instantaneous communications and available on-line services continue to reduce the physical distance between individuals. Almost anything is now available in cyberspace from shopping, schooling and education, on-line trading, banking, to social and political on-line communities. On-line service providers are shifting from a product centric approach to a more personal and customized approach to marketing their products and services. The idea of one-to-one marketing is very powerful and has become an important tool for competing in the interactive age. One-to-one marketing takes a customer-orientated approach to selling; customers are treated as individuals with different interests and needs. We respond positively to individual attention; when we visit a web site we want to see products and services of interest to us not every available product. We do not want to waste our time. For many people, time is money and the convenience factor ways heavily on the decision to return to a web site. Are the benefits of electronic communication at the expense of our privacy? How does the Internet affect the availability and use of our personal information? The Internet brings another dimension to the issue of privacy. Whether you are voting on-line or buying a book from Amazon.com you must consider how much personal information has been collected about you, with or without your consent, and how it can be used. Policies governing privacy on the Internet are still not clearly defined and many on-line users do not understand how the information they provide will be used. How much... ...activity are all available at the press of a button. Soon we will have on-line refrigerators that can place grocery orders, washing machines that can access the Internet to determine the best wash cycle for a delicate fabric and Internet connectivity available from every room in the house. If we reap the benefits of communications technology, we must expect to pay the price with our privacy. Works Cited Bridis, Ted. Comcast Tracks Users Web Browsing. Los Angeles Times 12 Feb 2002. http:www.latimes.com/news/nationworld/politics/wire/sns-ap-internet-privacy/0212feb12.story (25 Feb 2002). Grossman, Lawrence K. The Shape of the Electronic Republic. Composing Cyberspace. Richard Holeton. United States: McGraw-Hill, 1998, 311-327. Birkets, Sven. Into the Electronic Millennium. Composing Cyberspace. Richard Holeton. United States: McGraw-Hill, 1998, 311-327.