What Is Zooplankton, or Animal Plankton

There are two basic forms of plankton: zooplankton and phytoplankton. Zooplankton (also known as animal plankton) can be found in both saltwater and freshwater. There are estimated to be over 30,000 species of zooplankton. Ocean Plankton Ocean plankton are, for the most part, at the mercy of the vital forces of the seas. Having little or no powers of mobility, plankton  are either too small to compete against ocean currents, waves, and wind conditions, or when large—as in the case of many jellyfish—lacking in sufficient propulsion to initiate movement on their own.   Fast Facts: Zooplankton Etymology The word  plankton  is derived from the Greek word  planktos,  meaning wanderer or drifter.  Zooplankton incorporates the Greek word  zoion, meaning animal.   Types and Classifications of Zooplankton Some species of zooplankton are born as plankton and remain so for their entire lives. These organisms are known as holoplankton and include such tiny species as copepods, hyperiids, and euphausids. Meroplankton, on the other hand, are species that begin life in a larval form and progress through a series of life stages to evolve into gastropods, crustaceans, and fish. Zooplankton may be classified according to their size or by the length of time they are planktonic (largely immobile).  Some terms that are used to refer to plankton include: Microplankton:  Organisms  2-20  µm in size which includes some copepods and other zooplankton.Mesoplankton:  Organisms  200  µm-2 mm in size, which includes larval crustaceans.Macroplankton:  Organisms 2-20  mm in size, which includes euphausiids (such as krill), an important food source for many organisms, including baleen whales.  Micronekton:  Organisms 20-200 mm in size, which includes some euphausiids and cephalopods.Megaloplankton:  Planktonic organisms greater than 200 mm in size, which includes jellyfish and salps.Holoplankton:  Organisms that are planktonic throughout their entire lives, such as copepods.  Meroplankton:  Organisms that have a planktonic stage, but mature out of it, such as some fish and crustaceans.   Zooplanktons Place in the Food Web Marine zooplankton are consumers. Rather than getting nutrition from sunlight and nutrients via photosynthesis like phytoplankton, they must consume other organisms in order to survive.  Zooplankton may also be carnivorous, omnivorous, or detrivorous  (feeding on waste).   Many species of zooplankton live in the euphotic zone of the ocean—the depths at which sunlight can penetrate—feeding on phytoplankton. The food web begins with the phytoplankton, which are primary producers. Phytoplankton convert  inorganic substances including energy from the sun and nutrients such as nitrate and phosphate into organic substances. The phytoplankton, in turn, are eaten by zooplankton, who are consumed by ocean creatures ranging in size from smaller fish and gastropods to gigantic whales.   The days for many species of zooplankton often involve vertical migration—ascending toward the ocean surface in the morning when phytoplankton are more plentiful, and descending at night to escape predation. Since zooplankton generally comprise the second step in a food web in which they dwell, this daily ascent and descent has an impact on the rest of the species they feed on, and in turn, those that feed on them. Zooplankton Reproduction Zooplankton may reproduce sexually or asexually, depending upon species.  Asexual reproduction is more common for holoplankton and can be accomplished  through cell division, in which one cell divides in half to produce two cells, and so on.   Sources Harris, R., Wiebe, P., enz, J., Skjoldal, H-R., and M. Huntley.   ICES Zooplankton Methodology Manual. Marine Education Society of Australasia. Zooplankton. Morrissey, J.F. and J.L. Sumich. 2012. Introduction to the Biology of Marine Life, Tenth Edition. Jones Bartlett Learning, LLC.  467pp.Woods Hole Oceanographic Institution.  Jellyfish and Other Zooplankton.  Accessed May 30, 2014.   Census of Marine Zooplankton  Zooplankton. Center for Coastal Studies Provincetown.

Gay Marriage Position Paper - 992 Words

Position Paper: Should Gay Marriage be Legalized? In America, marriage has been traditionally defined as a legally recognized commitment between a man and a woman as their ultimate expression of love. Throughout recent years, homosexual relationships have become more accepted than ever before in our country. â€Å"Civil unions,† or ceremonies celebrating the affirmation of same-sex partnerships, have become available to gay and lesbian couples, though they undeniably are not the same thing as marriages. Much national debate has risen over whether gays should be legally allowed to marry rather than be forced to have civil unions. I personally believe that gay marriage should not be legalized because it would undermine the term†¦show more content†¦Studies show that homosexuals, for a variety of reasons, have life expectancies of approximately 20 years less than the general population. (BalancedPolitics.org). HPV, Hepatitis A, B, and C, Gonorrhea, Syphilis, â€Å"Gay Bowel Syndrome,† and HIV/AIDS have all been found to be more prevalent in homosexual than heterosexual men, while lesbian women have a higher prevalence of Bacterial Vaginosis, Hepatitis C, HIV risk behaviors, and cancer risk factors such as smoking, poor diet, and obesity compared to heterosexual women. Homosexuals also have more mental health problems such as alcohol and drug abuse, Nicotine dependence, depression, and suicide. It has also been proven that these problems do not result from discrimination from the heterosexual majority, because areas with more tolerance of homosexual relationships were found to have higher rates of physical and mental health problems, suggesting that the real problem lies in the homosexual lifestyle itself. (Sprigg 87). Just as unhealthy lifestyles of smoking and drinking should be discouraged, so should homosexuality. When we make members of our society physically and mentally unhealthy, we continue to further weaken our country. All things considered, there is just no way that the legalization of gay marriage could be beneficial to our country, and for this reason I doShow MoreRelatedPosition Paper-Gay Marriage1469 Words   |  6 PagesMarriage. When most people think of an ideal â€Å"marriage†, a man and a woman sharing vows and devoting their lives to each other is what is pictured. Well, this is only 100 percent true in most cases. Today’s society has accumulated different types of marriages: a marriage between a man and a woman, between a man and a man, or between a woman and a woman. Though each of these unions may not all be legal in each of the 50 states, couples still proceed with the ceremonies. I feel as though thereRead MoreFeminism Of A Post Feminist Period Essay1692 Words   |  7 PagesPosition paper 1. 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In particular, transgender individualsRead MoreThe Individual and the Corporation: Kathy Levinson and E*Trade a Case Study1566 Words   |  7 Pages......................6 Conclusion†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦...†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦...7 References†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦..9 Introduction This case study research paper will examine the case of Kathy Levinson, former President and Chief Operating Officer of E*Trade and her personal decision about openly supporting gay rights initiative in California. The case was originally created by Joseph Badaracco, Jr. of the Harvard Business School. The purpose of the case study project is to provideRead More Against Legalizing Homosexual Marriages Essay1293 Words   |  6 PagesAgainst Legalizing Homosexual Marriages The legalized marriage of individuals with the same gender is drawing more attention these days. When asked, most people want to avoid the subject of homosexuality altogether or they have a very strong opinion on it. The debate over whether the United States should allow homosexual couples to marry legally is giving rise to a new social dilemma in our country. This question has courtrooms nervous, churches wavering and equal rights activists angry. CourtroomsRead MoreThe Uk Civil Partnership Act 20041670 Words   |  7 Pagesarticle involves analysis of various literature and researches on the policies and laws that govern lesbian and gay equality. The mention of the different definitions and arguments pave the way for the introduction of the UK Civil Partnership Act 2004 (Taylor 589). According to the introduction part of the reading, same-sex legal recognition has always revolved around two specific positions that are framing the lesbian law towards equality or view acknowledg ment as an accommodation to heterosexual valuesRead MoreSame Sex Marriage Should Be Legalized Essay1289 Words   |  6 PagesCould you imagine if you had met the ideal person you wished to share your entire life with but the law would not allow you to? That is the position that many homosexual Australians have been in since the settlement of this country. Same sex marriage is currently not allowed in Australia but I and a proven 60% of other Australians strongly believe it should be. Gay people pay taxes, serve in the military, participate in the workforce, are our neighbors, friends and family.   Logic and decency would suggest

Taybeh Brewing Company Free Essays

†¢Joint venture with Jordan †¢Sales promotion such as T- shirts, pens, caps †¢Beer festival †¢Sponsor a local team †¢Organize camps for people. TBC can make a joint venture with a company in Jordan, as that would bring down the import tax considerably. This way it can enter the Jordan market with lower prices and higher profits. We will write a custom essay sample on Taybeh Brewing Company or any similar topic only for you Order Now To improve the sales within Palestine, it can market its product by distributing sales promotion items such as bottle openers, t- shirts, caps, pens and so. This marketing skill would not cost a lot to the company but is very effective. The beer festival â€Å" oktoberfest† is celebrated in Palestine by TBC. This should be continued for a lot of years ahead and all the local people and tourists should be given free beer. This way it will become a tradition in few years and TBC will have a lasting impression in everyone’s mind TBC can also be the sponsor for a local sports team. As for me in UK all I know about Aon is only through MANU. A lot of people get attracted towards sporting events and thereby this should help the company in a good way if they have their name up on one of the local teams. Palestine is a developing country and lot of riots have been happening in the country from few years. If the camps are organised for the needy people where basic requirements such as food and shelter are provided then it would help build public relations. How to cite Taybeh Brewing Company, Papers

Usage And Value Of ICT In A Daily Operations Of A Travel Company

Question: Discuss about the Usage And Value Of ICT In A Daily Operations Of A Travel Company. Answer: Usage and value of ICT in a travel company Development in the field of ICT (information communications technology) has deeply impacted the way tourism or travel businesses organizations performed their different activities and operations. If we consider the reservations or bookings by a tours and travels company, the computerised reservation systems have made it easy to store and retrieve the customer informations for making the reservations. Use of flight tracking system in order to stream line processes: This type of ICT technology is used by the travel organizations to manage as well as monitor the travel details of the specific tour package softwares like RadarBox24, Plane Finder, Flight Stats.com are useful in tracing the schedules and details. On the other hand, the use of different tools like dynamic packaging is used by the organizations in order to provide the freedom to the customers to develop a self-made package other than the predetermined packages. Use of the biometric passport is also used by the travel organizations for the identification of the traveller through the containing biometric information of a specific traveller (Standing, Tang-Taye Boyer, 2014). GDS (Global Distribution System) is another technology that makes the operations of a travel agency much easier (Neuhofer, Buhalis Ladkin 2014). GDS is helpful in forming a linkage between the different service providers with the company in the travel industry, for example, aircrafts, car rental organizations and empowering automated transactions between both the parties. Using the latest and improved ICT tools the travel companies can upgrade the level of collaboration between the travel organization and different service providers in the industry; pre-planning with specific service providers (hotel booking, car rental) no longer essential for the companies; The Web is helpful for the organizations to distinguish choices, empowering holiday packages to be developed; Us of the new technologies provides the organization better negotiation power for the services to be bought or collaborated with service providers and customization of those services. References Neuhofer, B., Buhalis, D., Ladkin, A. (2014). A typology of technology?enhanced tourism experiences. International Journal of Tourism Research, 16(4), 340-350. Standing, C., Tang-Taye, J. P., Boyer, M. (2014). The impact of the Internet in travel and tourism: A research review 20012010.Journal of Travel Tourism Marketing,31(1), 82-113. Xiang, Z., Magnini, V. P., Fesenmaier, D. R. (2015). Information technology and consumer behavior in travel and tourism: Insights from travel planning using the internet. Journal of Retailing and Consumer Services, 22, 244-249.

Ascribed and Achieved Status free essay sample

Status is the social position a person occupies within a social group with a role that our society expects us to play in a given status. For example, a man may have the status of father in his family. Because of his given status, he is expected to fulfill a role for his children, and in most societies that would require for him to nurture, protect, guide, and educate them. It is quite the same as having the role as mother. Statutes can vary significantly from culture to culture. However, in all societies they are either ascribed or achieved status. Ascribed status is the social position society assigns to an individual on the basis of factors and which the individual has no control of. For example, we have no control over our sex, gender, race, economic status, and ethnic background into which we are born. We do not have an option to choose them, they are not voluntary statuses. We will write a custom essay sample on Ascribed and Achieved Status or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Throughout our life we are assigned statuses that we cannot control, such as â€Å"child†, â€Å"teenager†, â€Å"adult†, or â€Å"senior citizen† on the basis of our age. We do not pick our gender or the family that we are born into. On the other hand, an achieved status is one that is acquired by doing something.For instance, someone becomes a criminal by committing a crime. Or a woman becomes a mother by having a baby. As well as the status of a widow, by the death of her husband and so on. In achieved status you have some control in either becoming a college graduate, parent, spouse, prison inmate, bank president, etc. ; it just depends on your own efforts, choices, and behavior. Although, an individual’s ascribed status may affect the likelihood of achieving other statuses, one can still succeed depending on how much enthusiasm is brought upon.For example, if you are born into a poor socioeconomic status, it may be more difficult to achieve the status of â€Å"college graduate† because of the high cost of a college education. Every individual has numerous statuses all at once. You may be a student, parent, tutor, female, and Hispanic. The most significant status in a person’s social identity is their master status. Usually, a person’s master status is their occupational status. For example, if you are a full-time student, your master status is likely to be â€Å"student†.An individual’s master status typically takes the place of other identifying traits the individual may have. Let us say if a woman feels that her role as a mother is more important than her role as a woman, a wife, or a daughter, it is more likely for her to label herself first as a mother and to be able to identify with other women who label themselves as such. Unlike the status set, the master status affects how the individual behaves in almost every given situation. Master statuses may have several negative effects on an individual.For example, if a person is physically disabled, this can become the master status of that individual. That person will likely become â€Å"the blind woman†, â€Å"the paralyzed guy† etc. If the person suddenly becomes disabled, their former identity is taken away and their new master status is given. It is likely for that person to be treated and seen differently by the people they know. This also becomes an issue when a person is labeled as â€Å"gay†, â€Å"black†, â€Å"criminal† and so on. Another example is if there is a black man who is a son, father, or a school principal, the status of being a black American takes over all of those other statuses. Also, a woman can be a great mother, a doctor, or a church leader, but once she deals with men, the most important status that will surpass the others is her status of being a woman. Finally, each individual carries a social position in life (status). All of us have an ascribed status which can not be chosen or controlled. We are simply born into it. And, it is up to our efforts, actions, and behavior, that control our achieved status. So in other words, we are who we are and only we can change that depending on how we want to live our lives.

The Two Paths essays

The Two Paths essays Within John Ruskins Book The Two Paths he discusses many of his ideas, concerns and theories on art and art culture. I will cover but four of what I think to be the more interesting concepts. Balancing true representation of form and abstract human expression in an artwork. The effect art has on a cultures behaviour and vice versa. The idea that the human hand will never be surpassed in its ability to create true art. And finally, I will discuss Ruskins position on the distinction between art for arts sake, or art for self-recognition and wealth. Born in London, February 8, 1819, John Ruskin was destined to be either a man of God or a man of art and literature. His mother Margaret Cox was a devoted Christian who had dedicated her only child to God before Ruskin was even born. His first education was to be that of the bible, and due to his mothers strict policy of being a Christian, he would end up learning it well. His father, though no less strict, was a highly cultured man. He was not only a collector of art, but also a lover and writer of poetry. This mix of strictness and culture, caused Ruskins upbringing to be a very successful one in which he learnt to write verse by the age of eight, began taking lessons from a drawing master at age ten, and had his first works published by the age of fifteen. It was his strict upbringing, his educated outlook on the world and a copy of Rogers Italy by which was partly illustrated by J.M.W. Turner that influenced his stance on the world of art, architecture and poetry all around hi m. Although Ruskin suffered from a lot of mental illness throughout his life he was still able to write the most profound statements that often seem to encapsulate what I think to be the truth about art. Of all writers on art, Ruskin is the most difficult to evaluate today (Fishman,1963, 14). This statement is certainly powerful, and ...

Mathematical Formula in Material Cost Accounting and Control Essay

Mathematical Formula in Material Cost Accounting and Control - Essay Example Also, overstocking requires more storage space which, in turn, means an increase in insurance expenses, storage costs and deterioration in quality and depreciation in quantity. On the other hand, if materials are understocked, frequent orders have to be placed in small quantities and there is a chance of "stock outs" also. Hence, the tack of the manager is to find the most economic order which s very essential for cost management and control. The cost of carrying the inventory and the ordering cost is inversely proportional to each other. The costs of placing the order decreases as the size of the order increases, because with the bigger size of the order, the number of the orders will be lower. However, simultaneously the costs of carrying the inventory will go up because the purchases have been made in large quantities. It may be possible to have appointed which provides the lowest total cost and the point, which is the ideal size of the order is known as the Economic Order Quantity(EOQ). The EOQ is one where the cost of carrying inventory is equal or almost equal to the cost of not carrying inventory (cost of placing the order), i.e., at EOQ level, the total of inventory carrying cost and the ordering cost is minimum which can be determined mathematically s follows: The EOQ is 600 units, i.e., 10 orders per year are needed.

Several topics. See below Essay Example | Topics and Well Written Essays - 16250 words

Several topics. See below - Essay Example The research conducted in this study points to the lack of assertiveness in political and social goals which risks political irrelevance. Methodologies The researcher conducted quantitative research of existing literature related to many aspects of the civil service organisation/union. Firstly, the researcher conducted a review of actual standards through publications of the Public Service Union, and German Civil Servants' Union (DBB). The researcher then considered the organisational structure of these associations, taking into account the principle-agent theory. Next, the researcher addressed the role of lobbying in the trade union environment on order to explain the basic tasks of interest group representatives, and to evaluate the significance of the associations. Through this analysis, the researcher documented the operating techniques of lobbyists. The researcher, throughout this process, gained insight into the potential influences of planning association, financing, personnel policy and leadership. The researcher then began investigating the importance of strategic alliances and networks by listing selected alliances and networks and then constructing a block model analysis.In order to assess stakeholder networks, the researcher narrowed down the subject to one important field of activity which is non-profit marketing. This activity includes finding considerations which take buy-out-reflections into account. The researcher further investigated the application of risk management and corporate governance. Through the investigation of existing literature and current organisational examples, the researcher was able to summarize theoretical results and future challenges and how organisations can meet those challenges through organisational re-structuring both in the organisation and through its networks and alliances. Contextualisation of Research The research conducted in this study does not aim to define a single solution; its main intention is to document the role of lobbying in within the union environment and the related need for the use of strategic alliances and networks. As such, the researcher aimed to reflect upon theoretical analytical foundation, also known as stakeholder value. The research conducted can be helpful in the design of sustainable lobbyist work and the optimization of organisational ideas. It also opens the doors for improved operational and organisational structures. The primary research result of this study is the importance of transparency within organisations; meaning there is a need for clear and specific communication of objectives both internally and externally. Currently, organisations lack clearly defined objectives and networks and organisational structures are not efficient. Therefore, the goal of organisational success should be to increase efficiency within organisational structures and networks through the clear definition of objectives; which includes: Legal objectives Economic goals Social goal s Target group This also requires improved approaches to representation inside and outside of the organisation, which can be achieved through increased transparency and respect both for and by the unions. The overall objective of this research was achieved and the researcher is excited about the implications of this research on further study or organisational restructuring as it pertains to the civil service organisation. Research Results

Country analysis Essay Example | Topics and Well Written Essays - 500 words - 1

Country analysis - Essay Example Shimko attributes the economic deterioration in Afghanistan to a military strike and transformation that followed after 9/11 attacks. United States had resolved to fight terrorism by targeting heads based in Afghanistan. Military revolution) affect the economic situation of the country especially if one of the countries is superior in terms of technology, military, and economically (Shimko 17. Afghanistan belongs to the periphery countries. It shares a small percentage of the global wealth despite owning oil ores. The agricultural, labor, and natural resource system of Afghanistan is dependent on the status of the government and the level of dependence on foreign aid. Shimko notes that the effect of post Middle-East American military action has resulted to a country that is struggling to get the economic condition on its feet. The country registered a slow economic growth rate since 2013 due to weak governance capacity after the anti-terrorism wars. The country has failed to implement operations together because of unending wars since the invasion by Soviet Union in 1979 (Shimko 31). Afghanistan used to contribute an integral share to the agricultural sector of the world before the war and unending political instability. It used to export surplus produce to USA, France, India, and Pakistan before Cold War and US invasion in 2001. The insurgence of military forces does not only seek to boost security against terrorism, but also control mineral deposits that could turn the country into a world-mining center. However, the country is among the poorest countries in the global economic position platform. Afghanistan would subsidize and protect copper, iron, cobalt and lithium mineral deposit in a bid to boost its mining industry. The deposits remain unutilized because of the prevailing poor economic status. However, the country is struggling in weak government and post-terror

Comparison of different modulation technique

Comparison of different modulation technique 1. INTRODUCTION 1.1 Modulation is the process of varying one waveform in relation to another waveform. In telecommunications, modulation is used to convey a message, or a musician may modulate the tone from a musical instrument by varying its volume, timing and pitch. Often a high-frequency sinusoid waveform is used as carrier signal to convey a lower frequency signal. The three key parameters of a sine wave are its amplitude (volume), its phase (timing) and its frequency (pitch), all of which can be modified in accordance with a low frequency information signal to obtain the modulated signal. 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 (sometimes detector or demod). 1.2 TWO TYPES OF MODULATION A) Analog modulation B) Digital modulation Here we discuss analog modulation techniques. 2. AMPLITUDE MODULATION Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent. For example, changes in the signal strength can be used to reflect the sounds to be reproduced by a speaker, or to specify the light intensity of television pixels. (Contrast this with frequency modulation, also commonly used for sound transmissions, in which the frequency is varied; and phase modulation, often used in remote controls, in which the phase is varied). 2.1 TYPES OF AMPLITUDE MODULATION As originally developed for the electric telephone, amplitude modulation was used to add audio information to the low-powered direct current flowing from a telephone transmitter to a receiver. As a simplified explanation, at the transmitting end, a telephone microphone was used to vary the strength of the transmitted current, according to the frequency and loudness of the sounds received. Then, at the receiving end of the telephone line, the transmitted electrical current affected an electromagnet, which strengthened and weakened in response to the strength of the current. In turn, the electromagnet produced vibrations in the receiver diaphragm, thus closely reproducing the frequency and loudness of the sounds originally heard at the transmitter. In contrast to the telephone, in radio communication what is modulated is a continuous wave radio signal (carrier wave) produced by a radio transmitter. In its basic form, amplitude modulation produces a signal with power concentrated at the carrier frequency and in two adjacent sidebands. This process is known as heterodyning. Each sideband is equal in bandwidth to that of the modulating signal and is a mirror image of the other. Amplitude modulation that results in two sidebands and a carrier is often called double sideband amplitude modulation (DSB-AM). Amplitude modulation is inefficient in terms of power usage and much of it is wasted. At least two-thirds of the power is concentrated in the carrier signal, which carries no useful information (beyond the fact that a signal is present); the remaining power is split between two identical sidebands, though only one of these is needed since they contain identical information. To increase transmitter efficiency, the carrier can be removed (suppressed) from the AM signal. This produces a reduced-carrier transmission or double-sideband suppressed-carrier (DSBSC) signal. A suppressed-carrier amplitude modulation scheme is three times more power-efficient than traditional DSB-AM. If the carrier is only partially suppressed, a double-sideband reduced-carrier (DSBRC) signal results. DSBSC and DSBRC signals need their carrier to be regenerated (by a beat frequency oscillator, for instance) to be demodulated using conventional techniques. Even greater efficiency is achieved—at the expense of increased transmitter and receiver complexity—by completely suppressing both the carrier and one of the sidebands. This is single-sideband modulation, widely used in amateur radio due to its efficient use of both power and bandwidth. A) DSB-FC In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing power as a result of the modulation process. The sidebands consist of all the Fourier components of the modulated signal except the carrier. All forms of modulation produce sidebands. Amplitude modulation of a carrier wave normally results in two mirror-image sidebands. The signal components above the carrier frequency constitute the upper sideband (USB) and those below the carrier frequency constitute the lower sideband (LSB). In conventional AM transmission, the carrier and both sidebands are present, sometimes called double sideband amplitude modulation (DSB-AM). In some forms of AM the carrier may be removed, producing double sideband with suppressed carrier (DSB-SC). An example is the stereophonic difference (L-R) information transmitted in FM stereo broadcasting on a 38kHz subcarrier. The receiver locally regenerates the subcarrier by doubling a special 19kHz pilot tone, but in other DSB-SC systems the carrier may be regenerated directly from the sidebands by a Costas loop or squaring loop. This is common in digital transmission systems such as BPSK where the signal is continually present. B) SSB-SC Single-sideband modulation (SSB) is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth. Amplitude modulation produces a modulated output signal that has twice the bandwidth of the original baseband signal. Single-sideband modulation avoids this bandwidth doubling, and the power wasted on a carrier, at the cost of somewhat increased device complexity. C) SUPPERESED CARRIER Reduced-carrier transmission is an amplitude modulation (AM) transmission in which the carrier wave level is reduced to reduce wasted electrical power. Suppressed-carrier transmission is a special case in which the carrier level is reduced below that required for demodulation by a normal receiver. Reduction of the carrier level permits higher power levels in the sidebands than would be possible with conventional AM transmission. Carrier power must be restored by the receiving station to permit demodulation, usually by means of a beat frequency oscillator (BFO). Failure of the BFO to match the original carrier frequency when receiving such a signal will cause a heterodyne. Suppressed carriers are often used for single sideband (SSB) transmissions, such as for amateur radio on shortwave. That system is referred to in full as SSB suppressed carrier (SSBSC) or (SSB-SC). International broadcasters agreed in 1985 to also use SSBSC entirely by 2015, though IBOC and IBAC digital radio (namely Digital Radio Mondiale) seems likely to make this irrelevant. D) VSB A vestigial sideband (in radio communication) is a sideband that has been only partly cut off or suppressed. Television broadcasts (in analog video formats) use this method if the video is transmitted in AM, due to the large bandwidth used. It may also be used in digital transmission, such as the ATSC standardized 8-VSB. The Milgo 4400/48 modem (circa 1967) used vestigial sideband and phase-shift keying to provide 4800-bit/s transmission over a 1600 Hz channel. E) QAM Quadrature amplitude modulation (QAM) is both an analog and a digital modulation scheme. It conveys two analog message signals, or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves, using the amplitude-shift keying (ASK) digital modulation scheme or amplitude modulation (AM) analog modulation scheme. These two waves, usually sinusoids, are out of phase with each other by 90Â ° and are thus called quadrature carriers or quadrature components — hence the name of the scheme. The modulated waves are summed, and the resulting waveform is a combination of both phase-shift keying (PSK) and amplitude-shift keying, or in the analog case of phase modulation (PM) and amplitude modulation. In the digital QAM case, a finite number of at least two phases, and at least two amplitudes are used. PSK modulators are often designed using the QAM principle, but are not considered as QAM since the amplitude of the modulated carrier signal is constant. 3) FREQUENCY MODULATION frequency modulation (FM) conveys information over a carrier wave by varying its frequency (contrast this with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant). In analog applications, the instantaneous frequency of the carrier is directly proportional to the instantaneous value of the input signal. Digital data can be sent by shifting the carriers frequency among a set of discrete values, a technique known as frequency-shift keying. CARSONS RULE A rule of thumb, Carsons rule states that nearly all (~98%) of the power of a frequency-modulated signal lies within a bandwidth of where , as defined above, is the peak deviation of the instantaneous frequency from the center carrier frequency . Normal signal Modulated signal 4) PHASE MODULATION Phase modulation (PM) is a form of modulation that represents information as variations in the instantaneous phase of a carrier wave. Unlike its more popular counterpart, frequency modulation (FM), PM is not very widely used. This is because it tends to require more complex receiving hardware and there can be ambiguity problems in determining whether, for example, the signal has changed phase by +180Â ° or -180Â °. CARSONS RULE Suppose that the signal to be sent (called the modulating or message signal) is m(t) and the carrier onto which the signal is to be modulated is Annotated: carrier(time) = (carrier amplitude)sin(carrier frequencytime + phase shift) This make the modulated signal This shows how m(t) modulates the phase the greater m(t) is at a point in time, the greater the phase shift of the modulated signal at that point. It can also be viewed as a change of the frequency of the carrier signal, and phase modulation can thus be considered a special case of FM in which the carrier frequency modulation is given by the time derivative of the phase modulation. The spectral behaviour of phase modulation is difficult to derive, but the mathematics reveals that there are two regions of particular interest: For small amplitude signals, PM is similar to amplitude modulation (AM) and exhibits its unfortunate doubling of baseband bandwidth and poor efficiency. For a single large sinusoidal signal, PM is similar to FM, and its bandwidth is approximately, where fM = ωm / 2Ï€ and h is the modulation index defined below. This is also known as Carsons Rule for PM 5) SPACE MODULATION Space modulation is a radio Amplitude Modulation technique used in Instrument Landing Systems that incorporates the use of multiple antennas fed with various radio frequency powers and phases to create different depths of modulation within various volumes of three-dimensional airspace. This modulation method differs from internal modulation methods inside most other radio transmitters in that the phases and powers of the two individual signals mix within airspace, rather than in a modulator.

Unique Design of the Vietnam War Memorial Essay -- American America Hi

Unique Design of the Vietnam War Memorial At the age of twenty one, a female undergraduate at Yale University named Maya Lin submitted her design for the Vietnam Memorial. Her idea for the memorial was extremely unique and controversial. After long discussions by a panel, it was chosen for construction. The design that she submitted was one that was very different in comparison to other memorials, and it was one that has a tendency to leave a lot of questions on the minds of the visitors. On the face of the memorial there is a list of all those who died or are missing in the order by which they were lost. It could seem to some one who did not understand the incident that the monument honors only those lost, but that is incorrect. Maya Lin ¹s design formed into the most unique memorial structure of its kind, which honors all who served in the Vietnam War (Colliers 23: 137). The official name given to the monument was the Vietnam Veterans memorial. In this name alone it is clear that it was not erected for the sole purpose of honoring only those who were lost in the conflict. The term KIA was the abbreviation used for those people who were killed in action, and these people represent 47,000 of the 58,000 names on the wall. The other 11,000 were soldiers who died from crashes, snake bites, illnesses, and other non-combat related deaths (Olson 227). There is no distinction made between the two groups on the monument. The structure is a v-shaped polished granite slab that unlike other monuments has no message of honor or patriotism. All of those subjects are left to the thoughts of the beholder. People often find therapy in locating the name of a companion or a loved one. The Vietnam Veterans Memori... ... NAMES OF THOSE WHO GAVE THEIR LIVES AND OF THOSE WHO REMAIN MISSING ARE INSCRIBED IN THE ORDER THEY WERE TAKEN FROM US ². The Vietnam Veterans Memorial is also unique in the sense that is honors all who fought, as most monuments honor only those who died. From this one could imply that the veterans were not sufficiently honored by the people of America. (Colliers 139-140) It is clear that the erection of the Vietnam Veterans Memorial was a wonderful addition to the Washington Mall of monuments. There is some disagreement as to the exact meaning of the monument, but that is because in was designed for that very purpose. Maya Lin was quoted to say that she wanted a  ³quiet place, meant for personal reflection and private reckoning ² (Colliers 139) That was exactly what she gave to the country in her unique interpretation of what the monument should be.