Evolution of US Films Since the 1880s

Evolution of US Films Since the 1880s To what extent has film in the US evolved from the 1880s to modern day? Candidate Name: Dimitri Grigorov Abstract Film has gone through a drastic evolution since it began in the 1880s. There were 5 main stages regarding the evolution of film in the US. The Silent Period lasted from 1895 to 1929. This period brought the first films to the US. These films were black and white and featured no sound, other than some possible instrumentals. Silent movies appealed largely to illiterate immigrants because they didnt have to read, and it was a simple form of entertainment. The Classical Period lasted from 1930 to 1945. This time period was a huge leap forward because sound was introduced to movies. It was a new way to watch movies and people loved it. The Postwar Period, which lasted from 1946 to 1959, was the most historically significant era in the film world. The Transitional Period lasted from 1960 to 1979 and introduced new ideas to cinema that would shape the movies of today. The time period we are in now is known as the Contemporary Period and began in 1980. The Contemporary Period benefitted fro m technological advancements, and more elaborate films were made using CGI. Each time period had its own movements and iconic directors. Investigation Film has evolved since it began in 1880s. Film has gone from short black and white stop motion clips, to full fledged color spectacles with expensive special effects. It has gone from a fascinating gimmick to a new form of art. A lot can happen in the course of a century, and film has definitely changed in drastic ways. Film is an art. It influences people to change the world and to express themselves. Film gives people insight and inspiration in the darkest of days. In the late 1880s various people began experimenting with photo, blending them together to give the illusion of a motion picture. The technology and difficulty to capture that sort of video made motion pictures rare (boyslife.org). The first movie is a controversial subject. There are many differing opinions. Some believe it was The Horse In Motion, directed by Eadweard Muybridge in 1878. This groundbreaking motion photography was accomplished using multiple cameras and assembling the individual pictures into a single motion picture. Its something that you could do today, using a few cameras that are set to go off at an exact moment (lavideofilmmaker.com). The movie was created to answer a popular question of the time: Are all four of a horses hooves ever off the ground at the same time while the horse is galloping? The video proved that they indeed were and, more importantly, motion photography was born (boyslife.org). Not all people consider this film the first one, though. Some think the first film was Roundhay Garden Scene, released in 1888. Its a short clip directed by French inventor Louis Le Prince. While its just 2.11 seconds long, it is technically a movie (boyslife.org). According to the Guinness Book of Records, it is the oldest surviving film in existence (boyslife.org). Eventually, films got longer. Brothers Auguste and Louis Lumià ¨re became prominent figures in the film world. They created various short films and were among the first filmmakers in history. Their films were unique at the time because instead of lasting a few seconds, they lasted a few minutes. The brothers even infused some comedy into their films. In one scene, a man is watering his garden, while a boy is stepping on his hose. The man, not noticing the boy, wonders why water stops pouring out of it. This slapstick humor would later become more prevalent in films such as Charlie Chaplin. The Lumià ¨re brothers were also iconic in the film world because they devised an early motion-picture camera and projector called the Cinà ©matographe (cinema is derived from this name), according to britannica.com. This device was a leap forward because it allowed more people to simultaneously watch films. Previously, only one person at a time could watch . Originally, the device was invented and patented as the Cinà ©matographe Là ©on Bouly by French inventor Là ©on Bouly on February 12, 1892. Bouly coined the term cinematograph, from the Greek term for writing in movement. Due to a lack of money, Bouly was unable to develop his ideas properly and maintain his patent fees, so he sold his rights to the device and its name to the Lumià ¨re Brothers. In 1895, they applied the name to a device that was largely their own creation. They made their first film, Sortie de lusine Lumià ¨re de Lyon, that same year (wikipedia.com). By 1895, the silent film era arrived. The earliest American films were primarily a working-class pastime. Because they told stories without words, they appealed to the large, mostly illiterate immigrant population in the United States (the-artifice.com). After 1900, film became a more middle-class phenomenon, as filmmakers exploited films storytelling potential by adapting bourgeois novels, which incorporated middle-class values, for the screen (sparknotes.com). Until 1914, the major national film industries were located in Italy, France, and the United States. When World War I came, it devastated the Italian and French film industries, allowing American producers to gain the lead on the global market. The major American production companies combined their film technology patents and used their patent leverage to implement block booking on exhibitors (movie theater owners), which forced them to buy lower-quality product along with high-quality product (sparknotes.com). These exhibitors fought back by buying small production companies, and eventually managed to beat out the major producers because they were quicker to adopt feature-length films, which proved to be more commercially successful than the earlier shorts. From 1907-1913, many production companies moved from New York City to Los Angeles to work in the warm weather that allowed for year-round outdoor production, giving birth to the Hollywood film industry. The costs associated with vertical integration (the combination in one company of two or more stages of production normally operated by separate companies) forced Hollywood studios to seek investment from Wall Street bankers. This development, along with the industrial modes of production pioneered and the bourgeois storytelling conventions introduced, turned Hollywood into a profit-driven enterprise and its films into commercial products (sparknotes.com). One of the most prominent figures in US silent film was Charlie Chaplin. Between 1914 and 1918, Chaplin became the first international film star when he wrote, directed, and starred in short films as the Tramp, a silly figure with baggy pants, big shoes, funky mustache, snazzy suit, and cane. For Chaplin, comedy was a way to examine the impact of social conventions and taboos on personal freedom and happiness. His Tramp character had lots of charisma: sensible, brave, and wise but also flirty, vulnerable, and socially awkward. Chaplins criticism of leaders, moral and political issues, and material and psychological divisions between classes and genders reached its high point in later feature-length works, such as City Lights and Monsieur Verdoux (sparknotes.com). Film was making a name for itself. The idea of pictures coming to life was fascinating on a deep level. This kind of thing was universally recognized and respected. Movies with sound arrived on the scene. The era between 1930 and 1945 was called the Classical Period and was a monumental leap forward for the film world. The transition from silent to sound films caused great change in the film industry, requiring costly renovation of production studios and movie theaters, ending the careers of many silent film stars, and making it more difficult to sell films abroad. Hollywood took some time to overcome the artistic and technical challenges of sound film production, and the result was several years of bland output. For European filmmakers, production costs were expensive because Hollywood studios owned the patents to the new sound technology and licensed it at an expensive price. This allowed the US to continue to be dominant in the film world (sparknotes.com).By the mid-1930s, Hollywood entered a period of unmatched success and prosperity, with five major studios (Paramount, Warner Brothers, MGM, RKO, and Twentieth Century Fox) and three minor studios (Universal, Columbia, and United Artists) introducing unique styles, genres, and stars. In 1934, under pressure from religious organizations such as t he Legion of Decency, Hollywood implemented a Production Code that censored the content of its films, filtering out portrayals of lewd sexuality, bad language, graphic violence, and drug use. During World War II, Hollywood contributed enormously to the war effort through the production of propaganda films (sparknotes.com). Despite the shift in film themes, the industry was soaring. Then World War II came. The period between 1946 and 1959 was known as the Postwar Period (britannica.com). The war affected American filmmakers and audiences, leading to the production of dark, morally ambiguous and socially critical films in the film noir style. The US made various films depicting the USSRs idea of communism in a negative light. This anti-Communist sentiment flourished as the U.S.s former ally the Soviet Union became its primary enemy. In the 1949 movie The Red Menace, an ex-GI named Bill Jones becomes involved with the Communist Party USA. While in training, Jones falls in love with one of his instructors. After a duration of being true followers of communism, they realize their mistake when they witness party leaders murder a member who questions the partys principles. When they try to leave the party, the two are marked for murder and hunted by the partys assassins (wikipedia.com). New York Times journalist Bosley Crowther points out that the characters in the film are highly overdramatized and villainous to an unrealistic extent. She implies that this discredits the accuracy of the film. Nevertheless, the film was released to the American public, infusing them with skewed information. Another 1949 propaganda film, The Woman on Pier Thirteen, previously known as I Married a Communist, shares similar themes. In this film, Brad Collins, former stevedore, is rising fast in a shipping company when local communist agitators use his former Party affiliation to extort his help in stirring up trouble. When Brad resists, communist femme fatale Christine works through his brother-in-law Don. But Brads new wife Nan sees that her husband and brother are under pressure; when she investigates on her own, party boss Vanning takes ruthless action (wikipedia.com). Again, communism is being portrayed in a negative light and as a threat to Americans. Communist leaders are being shown as evil and bloodthirsty. HUAC was formed to combat the threatof Communism. This organization tried professionals suspected of having Communist ties. As a result of the House Un-American Activities Committee (HUAC) hearings, many of Hollywoods most talented actors, directors, and screenwriters were blacklisted by the studios because of suspected ties to the Communist Party. Some moved to Europe, some continued to work by using colleagues names as fronts, and others saw their careers and lives ruined (sparknotes.com). In response to competition from the new medium of television, Hollywood made films that showcased cinemas distinctive qualities: stereophonic sound, large screen size, and color images, benefiting from the emergence of widescreen technology and better color film stock. By the mid-1950s, the blacklist and new technologies led Hollywood to concentrate on apolitical, spectacular films such as biblical epics, westerns, and musicals. A 1948 Supreme Court decision forced Hollywood studios to end their vertical integration policies, making the marketplace more competitive and increasing opportunities for independent and foreign producers (sparknotes.com). The Postwar Period is when many of the most influential directors of all time arose. People like Orson Welles and Alfred Hitchcock, directors who are still well known today, got their start in this era. These directors would go on to be the inspiration for many modern day directors. Orson Welles is very well known because he was one of the youngest directors of all time. In 1940, Welles signed a $225,000 contract with RKO to write, direct and produce two films. The deal gave the young filmmaker total creative control, as well as a percentage of the profits. At the time, this was the most lucrative deal ever made with an unproven filmmaker. Welles was just 24 years old (biography.com). Unlike many of his contemporaries, Welles gained international recognition mostly on the basis of only that film, which was Citizen Kane (1941). The film is full of technical innovations, including crane shots, overlapping dialogue, multiple audio tracks, purposely grainy film stock, and low-angle photography. It explores themes that Welles would revisit throughout his career: the corruption of power and wealth, the fine line between desire and obsession, the precariousness of knowledge, and the limits of ego and ambition. Welless use of deep focus, long takes, and special lighting influenced a generation of filmmakers working in the postwar film noir and realist styles. Though rejected by audiences and undermined by studio executives throughout his career, Welles still managed to make several more highly acclaimed films, including The Lady from Shanghai (1948) and 1958s Touch of Evil (sparknotes.com). Perhaps the only director more iconic to this era was Alfred Hitchcock. In a career spanning half a century, Hitchcock got acclaim in both his homeland Britain and Hollywood. He directed some of the most memorable films of all time, including The 39 Steps (1935), Vertigo (1958), and North by Northwest (1959). Influenced by German expressionism and Soviet montage, Hitchcock used detailed visual and aural compositions to express his protagonists feelings of paranoia and claustrophobia, along with complex editing to create suspense. With a self awareness of society, Hitchcock examined the abnormal perversions and obsessive desires lurking beneath the surface of ordinary lives and communities, enabling him to become an astute observer of America in the 1950s, the decade during which he directed his greatest films (sparknotes.com). He would later be deemed as the master of suspense. By the time 1960 arrived, yet another era of film history began. The time between 1960 and 1979 was known as the Transitional Period. This period had its ups and downs but would eventually shape the modern movies we watch today. By the 1960s, Hollywood was in decline, unable to keep up with the radical political and cultural developments transforming American society. European films, however, fueled by government funding of film production, achieved unprecedented levels of critical acclaim and box-office success. The sophistication and creativity of these films led to the recognition of cinema as an artistic medium, not simply a form of mass entertainment (sparknotes.com). In contrast, Hollywood films in the early 1960s seemed devoid of style, boring, and out of touch. Less and less studio productions brought revenue. Hollywood reacted by cutting costs, entering into partnerships with independent and foreign producers, and allowing more flexibility in terms of experimentation (sparknotes.com). One exception to the low quality films produced in the 1960s was Alfred Hitchcocks Psycho. This film shocked audiences with a twist ending that audiences werent used to. The film was quite progressive for its time as well. The twist was that a man was dressing as his mother, taking on her identity, and killing women. Cross dressing, other than for comedy, was not popular yet and the fact that Hitchcock was daring enough to include this in his film, proved again to audiences that he was a force to be reckoned with. Still, most movies in the early 1960s were of lower quality unil Hollywood underwent another change in 1968. In 1968, the decades-old Production Code was scrapped, and the Motion Picture Association of America (MPAA) began to issue movie ratings, which enabled the industry to make more daring and challenging films. These changes, along with a middle-class migration to the suburbs that left urban movie theaters in disarray, led to new genres such as exploitation and hardcore pornography (sparknotes.com). More famous directors got onto the scene in the Transitional Period. One of these directors was Francis Ford Coppola. He directed four of the most important American films of the 1970s-The Godfather (1972), The Godfather Part II (1974), The Conversation (1974), and Apocalypse Now (1979). Coppola was also an accomplished producer and writer. Along with George Lucas, Martin Scorsese, and Brian De Palma, he was part of the first generation of filmmakers to attend film school. His training enabled him to combine visceral visual imagery, compelling storylines, and dynamic editing in order to create iconic portraits of American interests, whether at home or abroad. Coppola was renowned for his biting critique of the power dynamics of individual and family ambition amid the corrupting influence of American capitalism and imperialism (sparknotes.com). John Cassavetes was another memorable director from the Transitional Period. Considered the founding father of American independent cinema, Cassavetes was also a talented actor who accepted roles in Hollywood in order to fund his own films. His commitment to making films outside of the studio system became legendary and influenced a generation of American independent filmmakers. Cassavetes rejected the formulaic plots, essentialist characterizations, and tidy narrative resolutions of Hollywood cinema. His most influential films, Faces (1968), Husbands (1970), and A Woman Under the Influence (1974), feature iconic acting performances that reveal the raw emotional energy of human interaction, chronicling the struggle of characters to express themselves honestly and fully under the pressure of linear social and moral conventions (sparknotes.com).One of the few filmmakers to connect with the American counterculture was Arthur Penn, whose Bonnie and Clyde (1967) became the emblematic film of its generation. Influenced by the style and politics of the French New Wave and American underground cinema, Penn sought to overturn Hollywoods staid representational conventions. Bonnie and Clyde incorporates many of the characteristics that would define American cinema for the next decade: romantic anti-establishment heroes, explicit treatment of sexual and psychological issues, a negative portrayal of authority figures and societal institutions, graphic depiction of violence, genre hybridity (often a mixture of comedy and drama), and a refusal to resolve narrative conflicts tidily (sparknotes.com). By 1980, we reached our time period, the Contemporary Period. Multinational corporations bought and merged many movie studios, ending the period of artistic experimentation in Hollywood. The industry has returned to financial success and global dominance through the development of blockbuster franchises, large-scale marketing campaigns, and content aimed at children. It also has placed increasing emphasis on spectacular special effects in order to draw audiences into movie theaters. CGI was huge in this time period (empireonline.com). The emergence of affordable digital video cameras and the growth of the film festival circuit have expanded the possibilities for independent filmmakers around the world to produce, distribute, and exhibit films (sparknotes.com). American independent film has flourished in the past 25 years, as well, emerging as a voice for those who do not identify with the image of America that Hollywood has projected. Independent films often contain explicit treatments of sexual, political, and psychological issues and avoid formulaic plots with happy endings and clearly defined characters. They are made by and for women (Susan Seidelman, Julie Dash), racial and ethnic minorities (Charles Burnett, Lourdes Portillo), gays and lesbians (Todd Haynes, Su Friedrich, Julie Zando), working classes (Michael Moore, John Sayles) and other groups who are not adequately represented in mainstream cinema. Harmony Korine, John Waters, Jim Jarmusch, David Lynch, Terry Zwigoff, and Todd Solondz make films full of dark humor that explore the lives of social misfits who are often ignored or ridiculed in Hollywood films. The success of the independents has led many Hollywood studios to establish subsidiaries that distribute smaller-budget fil ms, blurring the lines of distinction between industrial and independent cinema. Key films include Jim Jarmuschs Stranger than Paradise (1983), David Lynchs Blue Velvet (1986), Steven Soderberghs Sex, Lies, and Videotape (1989), Spike Lees Do The Right Thing (1989), Quentin Tarantinos Reservoir Dogs (1992), and Wes Andersons 1998 film, Rushmore (sparknotes.com). Documentaries also soared in recent years. Challenging the tenets of direct, traditional cinema, many recent documentary filmmakers have included autobiographical and subjective elements in their films. Michael Moore and Marcel Ophuls insert themselves prominently into the fabric of their social and historical documentaries, both as on-camera interviewers and through voice-over, presenting themselves as near-mythical pursuers of truth and justice. Ross McElwee and Sadie Benning make introspective, essayistic films about their lives. Chris Marker and Marlon Riggs combine autobiography with political and philosophical analysis. Key films include Markers Sans Soleil (1983), McElwees Shermans March (1986), Ophulss Hà ´tel Terminus (1988), Moores Roger Me (1989), Riggss Tongues Untied (1990), and 1992s Bennings It Wasnt Love (sparknotes.com). The Contemporary Period gave us many of the directors we know and respect today. Directors like Steven Spielberg reinvented the way Hollywood works, and people like Oliver Stone brought a new edge to cinema. Spielberg has been at the forefront of Hollywoods reemergence as a dominant global industry. His 1975 film Jaws became the first modern blockbuster, revolutionizing the way Hollywood films are distributed and marketed. Jaws was released simultaneously in over 400 theaters, marketed extensively on national television, and timed for release in the summer, which linked thematically with its subject matter. In the 1980s, Spielberg showcased his storytelling talents with a series of hugely successful science fiction and adventure films such as Raiders of the Lost Ark (1981) and E.T.: The Extra-Terrestrial (1982), which explicitly appealed to younger audiences. These films brought families back into theaters with compelling stories that were in line with Reagan-era ideals of family values and American moral and technological supremacy (sparknotes.com). Unlike that of Spielberg, Stones controversial career has been defined by its rebuttal to modern American values and trends. In a period when American films have become less historical and oppositional, Stone has made four of the most important political films of his generation, Salvador (1986), Platoon (1986), Wall Street (1987) and JFK (1991), in which he looks critically at Americas military-industrial complex, capitalist institutions, and foreign policy. In an era defined by minimal political dissent, Stone has managed to produce controversial, instigating films because his considerable storytelling abilities have made many of his films commercially successful (sparknotes.com). Film has become a massive part of our society. Film influences pop culture, language, and fashion. Some movies teach us crucial life lessons, some expose American corruption, and some just provide us some much needed entertainment. The industry has evolved a lot since it began over a century ago. Every time period mentioned in this essay brought advancements to film. The Classical Period was a huge upgrade from the Silent Period because of the transition to sound. The Postwar Period was the most historically significant period of film. The Transitional Period reinvented the way Hollywood worked. The Contemporary Period shaped the films of today by introducing new concepts such as CGI and blockbuster multi part series. This is important because we can use films as doorways to the past. You can read about history, but to see it played out onscreen is incredible. By looking at films in the 60s, you can see how fashion then differed from the fashion we express today. By looking at a movi e from the 90s, you can see what slang was used back then. Film has shaped the world we live in today and will continue to do so in the future. Bibliography Eisenstein, S. (Director). (1925). The Battleship Potemkin [Motion picture on DVD]. Russia. Colman, D. (2011, September 20). The Birth of Film: 11 Firsts in Cinema. Retrieved October 04, 2016, from http://www.openculture.com/2011/09/the_birth_of_film_11_firsts_in_cinema.html Most Influential, Significant and Important Films in American Cinema Introduction. (n.d.). Retrieved October 04, 2016, from http://www.filmsite.org/mostinfluentialfilms.html 11 Essential Camera Techniques in Filmmaking With Animated Images. (n.d.). Retrieved October 04, 2016, from http://www.lavideofilmmaker.com/filmmaking/film-techniques.html Fox, D. (2015, October 20). The Room. Retrieved October 04, 2016, from http://moviepilot.com/ Bitoun, R. E. (2015, April 21). A History of Colour: The Difficult Transition from Black and White Cinematography. Retrieved October 04, 2016, from http://the-artifice.com/history-of-colour-film/ Semlyen, P. D. (2015, October 09). A History Of CGI In The Movies. Retrieved October 04, 2016, from http://www.empireonline.com/movies/features/history-cgi/ The Evolution of Acting. (2005, February 23). Retrieved October 04, 2016, from http://www.npr.org/series/4510430/the-evolution-of-acting The Film Rating System (CARA). (n.d.). Retrieved October 04, 2016, from http://filmratings.com/ Hurbis-Cherrier, M. (n.d.). Screenwriting. Retrieved October 04, 2016, from http://www.masteringfilm.com/the-key-stages-of-script-development-2/ Film Studies. SparkNotes. SparkNotes, 2011. Web. 17 Nov. 2016.

Wireless Sensor Networks: Applications and Forms

Wireless Sensor Networks: Applications and Forms 1 Wireless Sensor Network In this chapter, wireless sensor network (WSN) principles are being shortly introduced and discussed. In order to increase the level of understanding for analyzing Wireless Sensor Network (WSN) systems it is useful to study the technology behind them the technologies which are presented in this section. Wireless Sensor Networks (WSNs) are distributed and independent sensors that are connected and worked together to measure quantities such as temperature, humidity, pressure, noise levels or vibrations [5]. WSNs can measure vehicular movement (velocity, location, etc.) and monitor conditions such as lightning condition, soil makeup and motion [5]. Nowadays, WSNs are utilized in many common applications such as vehicle applications. Some of vehicle applications are: vehicle tracking and detection, tire pressure monitoring, vehicle speed detection, vehicle direction indicator, traffic control, reversing aid sensors etc. Such applications can be divided in major categories such as safety, security, environment and logistics. To implement WSN in an application and have an efficient system, first we need to consider about WSN technology, components and communication topology and protocols. Therefore, first, in this chapter, basic information about WSN components, the communication devices and process unit of WSN will be described. Then, the chapter will be followed by a description of the WSN topologies and protocols emphasizing on mesh WSN technology with ZigBee Protocol. 1.1 Wireless Sensor Network component To provide comprehensive view of WSN hardware, understanding of WSN components structure is required. Wireless sensors are small microcontrollers equipped with wireless communication device and an energy supplier. The architecture of WSNs is illustrated in Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 . As Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 shows the components of WSNs are sensing unit, processing unit, power supplier and communication device. The sensing unit consists of sensors and Analog to Digital Converters (ADCs). ADCs are responsible for gathering the signals and converting them into digital signals data and transfer them through each other using network topology to the processor unit. In the sensing unit, each sensor is called an ‘end node and varies in size and cost. The mission of these multifunction sensor nodes are to sense, process data and collaborate with other nodes [8]. Wireless sensor network can be positioned in two ways, either using a complex technique with the large sensors far from the object or using several sensors with an engineered design on position and topology [5]. In addition, each node provided with a wireless communication transceiver as a communication component. In the process unit, the controller and small memory storage are responsible for managing the collaboration within the sensors to achieve the assigning task. In addition, the communication device with a transceiver makes the network connection. Above all, the essential component of WSN is the power unit, which supports the power for all units [5]. One of the unique characteristics of sensor networks is that they are equipped with an on-board processor. This feature enables them to locally process some simple computations and broadcast only necessary processed data [5]. Network communication is really complicated and needs years of study [8], but to be able to implement WSN, we need to know some basic primary concepts of communication technology such as; network topologies, network protocol and their standards and specifications. 1.2 Communication technology To cover technical aspects of WSN, network topology and network protocol studying is needed. This study will help to provide information about reliability, robustness, security and stability and of WSNs software aspect to answer the research questions RQ. 1 ,RQ. 2 and RQ. 3 . 1.2.1 Topologies in WSN Communication In network communication, the big issue is how data transfers through nodes and nodes interconnect with each other. Several basic network topologies may be used for transmitting to and receiving from a node. The Alliance for Telecommunications Industry Solutions (ATIS) the standards organization of telecommunication industry explained the network topology as â€Å"The physical, real, logical or virtual arrangement of the nods/elements of a network† [9]. The topology shows the diameter and the number of nodes between any two nodes. Moreover how a data process and the data routing complexities are relied on the chosen topology. Consequently, some characteristics of a sensor networks such as latency, robustness and capacity are changed by their topology [10]. Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ2 is a graphic mapping of networks topology which shows the links of one or more nodes and explains the physical topology of the network. Despite having the same topology, two networks can differ in transmission rates because of their physical interaction, signal types and distance between nodes [9]. Table 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 describes the different types of network topology. Table 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 Topology TYPES [9]. Since Mesh topology is a main topic in the thesis, it is studied more in-depth in this section 1.2.1.1 Mesh Wireless Network Wireless mesh network is a term used when all wireless nodes are connected to each other within an ad-hoc multi-hob and mesh topology. In this network, any pair of nodes is able to communicate between each other within more than one path. In this network each node is used as a router to forward packets to the neighbor nodes which they have linked to. That means all nodes communicate directly or through other midway nodes without any manual configuration. Therefore, this network also called a self-configuration and self-organized network [11; 12]. As described in Table 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1, there are two types of mesh topology ‘Partially connected and ‘Fully connected (See Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ3). In a fully connected topology each node has the ability to communicate with all other nodes in the network and creates an interconnection links. By increasing the number of nodes in a mesh network, the number of links increases as well. On the other hand, in a partially connected topology, instead of direct interconnection between nodes, each node has two or more links to others to provide alternate routing and traffic balancing. Due to more links and indirect connections between nodes, traffic can flow through one or more router nodes to the destination [7] and create more reliable interconnections between nodes. Moreover, in partial network, the nodes are connected to either the node with higher rate of data transaction or the nearest neighbor node while in fully connected network all nodes have a direct links with each other. This multiple link path conducts a reliable communication. Therefore, whenever a connection fails or a node breaks down, the packages can automatically change their path by ‘jumping from a disconnected node. This is often called the self-healing of the network. This means that the networks connection stability and reliability are not essentially affected by node failures [11]. Due to the characteristics of wireless sensor network mesh, this network is self-configuring and self-organizing network in which each end-node is also used as a router (dual role- data originator /data router) to forward the signal packages all the way back of the main gateway. Therefore, due to the characteristics of mesh networks, this network is becoming one of the most implemented networks which able to have the flexible architecture for the network, easy self-configuration and robust fault tolerance connectivity [11; 12]. Additionally, the self-configuring characteristic of mesh WSN, bring the ability for the network to connect or disconnect nodes from the network. This brings the ability to grow/decrease the network by adding/removing nodes of a system. Mesh WSN has reliable self-healing and robust fault tolerance. This means if ­Ã‚ ­Ã‚ ­Ã‚ ­Ã‚ ­Ã‚ ­ a node fails or breaks down the signal packages jump from the disconnected node and automatically conducts a new path through the nearest node. However, the new path imposes re-routing and re-organizing to the network [5], which consumes too much power from the system. Therefore, having a power-aware protocol and algorithm is necessary for mesh network. ZigBee protocol is one of the protocols which provides this ability for WSN. 1.2.2 Protocols in WSN Communication WSN systems include variety of protocols for communication. Protocols need to program in different architectural layers. One of these architectural standard is OSI (Open System Interconnection) framework. In this session a brief introduction of each protocol and OSI are delineated. Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ4 shows the graphic overview of all wireless network technologies. This figure illustrated IEEE PAN/LAN/MAN technologies and clearly shows how these standards and protocols can be used in different conditions. For instance, 3G protocol is used to cover a long range of audio information in a wide area network (WAN) while for the same information in a short range and personal area network (PAN), Bluetooth is better. The standard conceptual rules set for data representation, data communication and error detection across two ends in telecommunication, are called communication protocols. These abstract rules represent in different layers of communication. There are different protocol stacks introducing different architectures for these layers such as AppleTalk, Distributed Systems Architecture (DSA), Internet protocol suite (TCP/IP) and Open Systems Interconnect (ISO/OSI). Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ5 (a) illustrates the different layers of an OSI Model and their functionalities. The OSI model has seven layers and each layer provides services for the upper layer and requests services from the lower layer. Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ5 (b) shows the typical communication protocols layers. Each of these layers has to deal with different issues regarding the communication procedure. As the typical protocol stack model shows in Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ5 the communication protocols should implement all layers from bottom to top. In addition, a management protocol needs to be applied in each layer to manage power efficiency, robust connectivity and connection reliability (see: Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ5 b). Below, rules and functionality for each layer are described: * Physical layer: is responsible for signal processing and physical interface connectivity between a device and physical medium and used bit stream in its data unit. It acted as communication channel for sensing and actuation in cost-efficient and reliable manner. Some examples of this layer are: IEEE 802.11b/g Wi-Fi, IEEE 802.15.1 Bluetooth, IEEE 802.15.4 ZigBee, etc. [7] * Data link layer: provides functionality toward channel sharing, Medium Access Control (MAC-Layer), timing (e.g. data time arrival), local link and capacity. It is responsible for detecting and correcting the data errors in physical layer and control the locality data comparison. It follows the protocols such as point-to-point protocol (PPP) and IEEE 802 Local Link Control (LLC). [7] * Network layer: is responsible for network routing functionality, network security, energy and power efficiency and reliability of the communication. It includes the network topology management and manages the information and detects errors in data transfer from router to router. A number of protocols is address in this layer such as: Internet protocol (IP), Threshold Sensitive Energy Efficient Sensor Network Protocol and etc. [7]. * Transport layer: provides end-to-end transportation (distributing and gathering) of data between end users. It includes storage and responds for caching and controlling the data to recover them back to the initial message that has been sent. Best-known protocols for this layer are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) [7]. * Upper layers: The Upper Layers are responsible for application processing, external query processing and etc. Upper layers include presentation layer session layer and application layer [7]. The summary of these standards and protocols are shown in Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ6 Among all the standard and protocols, IEEE PAN/LAN/MAN technologies are the ones applied in the majority of commercialWSNs to support physical layer and link-data layer signal transmission. As SOHRABY and ZNATI (2007) mentioned, the most common best-known protocols are:† (1) the IEEE 802.15.1 (also known as Bluetooth); (2) the IEEE 802.11a/b/g/n series of wireless LANs; (3) the IEEE 802.15.4 (ZigBee); (4) the MAN-scope IEEE 802.16 (also known as WiMax); and (5) radio-frequency identification (RFID) tagging† [7]. Each of these protocols has their own benefits and constraints. The comparisons between IEEE technologies are mentioned in Table 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ2. As Table 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ2 shows the IEEE 802.15.4 standard provides data rate of 20 to 250 kbps and operates in the 2.4-GHz ISM band. This standard covers signals in range of 10 m and requires the lowest power among other IEEE class. While IEEE 802.11a/b/g/n transmits the data in the rate of 54 Mbps ideal for wi reless internet connections and operates in the 2.4-GHz ISM (Industrial, Scientific and Medical) radio band as well as the 5-GHz ISM / 5-GHz U-NII (Unlicensed National Information Infrastructure) radio band. However, it requires much higher power consumption than IEEE 802.15 [7]. Recently, researchers put much effort to develop â€Å"a cost-effective standards-based wireless networking solution that supports low-to medium data rates, has low power consumption, and guarantees security and reliability† [7]. ZigBee Alliance is an association of companies which aims to provide such a standard for WSN consumers. Their mission is to have a simple, reliable, low-cost, low-power and standards-based wireless platform 1.2.2.1 ZigBee standard The ZigBee standard builds on IEEE 802.15.4 and is suitable for remote monitoring and controlling applications. Although it has lower-data-rates than the other standards, its reliability, security, long life battery with less complexity mechanism make it ideal for building automation in industrial network applications. The architecture of the ZigBee stack is established on the Open System Interconnection (OSI) model. The IEEE 802.15.4 defines the physical layer (PHY) and medium access control (MAC) sub-layer and In addition, ZigBee Alliance defines other functionalities for upper layers [7]. Figure 3à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ7 is a graphic overview of ZigBee protocol stack and shows the responsibility areas of IEEE 802.15.4, ZigBee Alliance platform and users applications [7]. This picture also shows the basic functionality of each layer. The data transmission service is provided by PHY layer and the protocol in this layer enables the connection between data units and the physical radio channel. ZigBee provides three different frequency band options for PHY layer. First, the transmission data-rate of 250kbps in 16 channels at 2.45GHz (Global) frequency. Second, with 40Kbps in 10 channels at 915MHz (Americas). And the last one, with 20kbps in 1 channel at 868MHz (Europe). The higher data-rate causes a higher order in modulation design and the lower frequency cause a larger cover area and better sensitivity. Depending on the power output, the transmission distance rate can change from 1 to 100 meters. (For more detail information see: Table 7à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 in Appendix A) ZigBee WSN has the ability to have static or dynamic network/component with either star or mesh topology and it has three types of nodes: a ZigBee Coordinator (ZC), ZigBee Routers (ZR), and ZigBee End-Devices (ZED). In order to have a communication protocol and physical connection both PHY layer and MAC sub-layers of the architecture should be defined upon agreement between server and clients. These layers require manual administrative procedures setting for server/client gateway. The next three levels namely: the network layer, security protocol and transport layer are defined by ZigBee alliance platform automatically. The last layer, application layer, has to interact with the user-interface and other applications; it ought to be programmed with high-level language so that integration with any existing devices applications becomes more conveniently practical. The ZigBee stack in gateway is responsible for all the network functionality such as network process management, authentication of the joined nodes, binding nodes and routing the messages throughout the network. ZigBee stack as a standard protocol, has clusters and libraries for improving the implementation process, therefore, using ZigBee compare to other protocols makes the system (including both hardware and software) development process much faster and easier. On the other hand, such standardisation provides easiness of adopt with third party sensors regardless of manufacturer, which might be attached to the network later. 2 Software Aspects To address the research question regarding the reliability, robustness, and security of any WSN application, it is essential to investigate the software architecture of that network. For convenience in description of the architecture of a WSN application, it is divided into three segments: Physical devices (such as lamps, sensors, nodes), Communication Protocol (terminals and servers, bridge, switch, network topology and standard) and Carried Information (application, functions, etc.). Any attempts to retain a precise design on software architecture for each part will cause an effective data transmission, which ensures reliability and security of the system [7]. Hence achieving any desired data transmission precision level in a WSN, network management (NM) techniques are applicable. Such techniques assist in network status monitoring, reliability and security amendment, and cooperation supervision between components [7]. NM techniques could also detect and resolve network faults in addition to restoring the system respectively [7]. In practice, designing WSN application necessitates tailoring NM techniques for each architectural segment. Various NM techniques regarding each segment are summarized as follows [7; 12; 5]: a) Physical architecture: Sensing and processing management, operation and administration, fault tolerance, maintenance, energy efficiency management, configuration management, performance management, security management, network element management. b) Communication architecture: Network management, networking protocols, network topology, function management, monitoring functions, fault management, performance management, security management, service management and communication, maintenance management, network configuration and organization, network behavior, data delivery model, sensor mobility, naming and localization, sensing coverage area, communication coverage area energy efficiency management c) Information architecture: Real-time information management, mapping management, service management, analyze information, control application, business application management report management, sending and receiving commands or response, naming, localization, maintenance, fault tolerance Aforementioned NM techniques enhance quality of the system. According to ISO 9126-1 software quality model Table 4à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ1 [13; 14; 15], the quality characteristics of a system could be divided into six fundamental properties: functionality, reliability, usability, efficiency, maintainability, and portability. According to the same documentation, these characteristics are broken to sub-characteristics such as suitability, security, maturity, fault tolerance, adaptability, analyzability, stability, testability and so on [13]. However, focusing on all subcategories collectively exceeds the time horizon of this research, from this stance three dimensions namely reliability, robustness and security are brought into attention. This section will be divided to two subsections describing the architecture issues and NM techniques for (1) Reliability and Robustness, (2) Security, of WSN and other characteristics is relegated to future studies. 2.1 Reliability and Robustness In WSNs context, the probability that a network functions properly and aggregates trustworthy data without any interruption continuously, is usually referred to as reliability characteristic of the network [23; 20]. According to ISO 9126-1 software quality documentation, reliability characteristic shows the capability of a network to maintain or re-built (re-start) the service in certain period of time [13]. So, it is important that during long sensing, the network has to service up continuously. Reliable service of a network includes precise and proper sensing, delivering and sending acceptable data to the base station. In other words as Taherkordi et al. (2006) put: â€Å"The less loss of interested data, leads us to higher reliability of a system†. Systematic approach perceives reliability as probability of data delivery to the base station rather than point-to-point reliability [16]. Robustness defined by Sohraby et al. (2007) as: â€Å"a combination of reliability, availability, and dependability requirements†, reflects the degree of the protocol insensitivity to errors and misinformation†. Achieving system robustness in WSN, necessitates system capability to detect, tolerate and confine errors as well as reconfigure and restart the network respectively [7]. According to the given definition by Sohraby et al. (2007), it is apprehensible that reliability and robustness share commonalities with each other; this is the main rational behind discussing these two attributes together in this section [7]. Considering the nature of communication in WSN, a network is unpredictable and prone to fail caused by any physical damages in hardware devices, energy depletion, communication link error, information collapses in packages and etc. [17; 16]. Therefore, one of the critical issues in design phase of WSN is applying fault tolerance techniques to optimize the network so that reliability and robustness attained [17]. These techniques enable the network to withstand and recover any upcoming failure and restart operation [13]. Liu et al. (2009) categorized fault tolerance techniques into: node placement, topology control, target and event detection, data gathering and aggregation, and sensor surveillance. Reminding from the beginning of this chapter architecture design divided into three segments. Table 4à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ2 depicted a summary of the plausible related faults and their solutions in each segment. In the following, each aforementioned fault tolerance techniques are being discussed in each design segment. Table 4à ¢Ã¢â€š ¬Ã¢â‚¬Ëœ2 The most probable fault and their fault tolerance solutions in WSN [17; 7; 18] 2.1.1 Reliability and Robustness of Physical Architecture: Fault: any physical interruption in sensor surveillance Solution: Node placement management and signal-effect management First item that should be considered in designing physical components architecture for reliability and Robustness is: physical placement and signal-effect management. As it is mentioned in section 3, although the mesh network communication is self-organize topology and does not need any manual configuration to bind the network for mobile sensors, the physical architecture and the location schema of the hardware components, sensors and gateways need to be designed carefully [7]. As a characteristic of mesh WSN, the sensors in network are free of any installation restrictions, even though, the placement should be far from any physical destruction or hostile locations. Inappropriate physical placement of sensor transmitters and gateway antenna can cause noise or significant lost in signals [7]. In addition, the signal coverage is decayed by surrounding objects and materials such as metal wall and the like. (E.g. exterior wooden, concrete, brick or gypsum frame, block or wall). Especially in the case of vehicles, the main body can impose such problem and henceforth installation of the sensors in this manner would be delicate. Moreover, the signal waves might be faded and affected during the transmission, due to various physical phenomena such as reflection, diffraction or scattering [7]. These effects would cause significant interruption in sensor surveillance. Therefore, it is important to manage these signal-effects in early stage of WSN physical architecture design. Reflection occurs when electromagnetic wave of signals is duplicated due to impinge of the wave on large object or surface such as walls, buildings and the Earth [7]. Therefore, all the reflection of the walls and also the Earth should be acknowledged in physical architecture design. Diffraction refers to any defection and obstruction in waves caused by irregular sharp edges during the data transmission between the transmitter and receiver [7]. In this case, designers have to be prudent in sensors placements in the proximity of sharp edges and corner angels. Scattering refers to any deviation from straight line. Environmental obstacles in the propagation path affect passing waves from their original structure. Even small irregular object such as street signs, and lampposts might encounter and scatter the wave. Hence WSN should be design to face with any irregular scattering during the wave transmission. Above all, the mobility of sensors and surrounding objects might fade the signals and add noises that should be considered in architecture design [7]. These issues are the basic physical factors, which cause major fault in data aggregation of WSN and cut down reliability and robustness. These destructive signals need to be subtracted from the received signal paths [7] before sending the data to gateway. Therefore, reflection, diffraction and scattering should be considered not only by designers in the physical components placements, but also by programmers in network development. Fault: Sensors failure Solution: Hardware replacement The next issue that needs to be considered in designing the physical architecture of a WSN is hardware failure. Sensors energy suppliers or any damages to the sensors and/or their transmitters are the sources of hardware failure. Regardless of source of failure, the WSN must be capable of functioning as well as replacing and switching sensors when necessary. Additionally, any changes in the physical components, on one hand, needs an explicit and well-defied consideration on security issue to prevent any potential threats, and on the other hand, needs an adaptable and configurable communication connection network [18]. 2.1.2 Reliability and Robustness of Communication Architecture Fault: communication link errors Solution:Topology control and event detection , Replicated services in communication model, Communication link error is an important concern in dealing with reliability and robustness of a network in communication architecture. The sensors in WSN are prone to fail and make link errors in point-to-point reliability of communication protocol. Therefore, it is the network topology responsibility to detect the errors and guarantee the overall reliability of the syste

Confessions For the Rest of Us :: Literary Analysis, God, Augustine of Hippo

Novels are written with the intent to entertain, textbooks to educate, and scripture to exhort. All writing has a purpose, intentional or otherwise. If this were not the case, writing would contain nothing of value. Autobiographies typically serve to inform the reader about the life of a specific person, yet, in Confessions, Augustine of Hippo displays loftier aims. Among other goals, he attempts to use his life story to indirectly guide others to God and truth, an objective to which he applies his considerable literary skill. Often famous historical icons seem to tower in the public eye, casting a shadow of influence that only increases through the ages; they seem somehow more than human. St. Augustine is just such a figure, yet his simple, candid commentary of his life in Confessions paints him as an ordinary man. Augustine went to great lengths to achieve this image, especially in the commencement of his narration. He begins by hyperbolizing his sin even in childhood stating, â€Å"At the time of my infancy, I must have acted reprehensibly† (Augustine 9), and continues this pattern of self-degradation throughout, not out of false humility, but to prove to his audience that he was not born a saint. Augustine spends greater time than necessary covering his ‘sin’ of stealing pears (Augustine 29-34), an act that most would consider a childish prank, and his sexual desires (in which he certainly was not the greatest sinner of his time) not only to explore the nature of transgression b ut also to build his reputation (or lack of it) with his reader (Augustine 24-28). Later in the narrative he describes what most would view as a moral triumph: I also recall how, when I had decided to enter for a poetry competition at the theatre, a soothsayer of some sort sent to ask what fee I would give him to ensure victory. But I replied that I hated and abominated those vile mysteries, and that even if the crown were immortal and made of gold, I would not allow a fly to be killed to bring about my success. For in his mysteries he would be going to kill animals, and by offering these creatures in honour of daemons, his intention was to gain their support for my winning. (Augustine 53-54) He then proceeds to condemn his intentions saying, â€Å"I refused sacrifice to daemons on my behalf; yet by adherence to that superstition I sacrificed myself to them† (Augustine 54).

Attica State Prison Uprising September 13, 1971 Essay -- Research Hist

Attica State Prison Uprising September 13, 1971 George Jackson the most famous political prisoner in the 70's and leader of the Black Panther Party was incarcerated at San Quentin Prison in California. He was killed by the State on August 21, 1971. Because of this Attica inmates organized a hunger strike and wore black arm bands. George Jackson's revolutionary writings in his book he had written "Soledad Brother'; was passed from inmate to inmate inside Attica State Prison, which had an enormous impact on the prisoners awareness of their feelings. Mr. Jackson's death lead to the direct uprising of New York's Attica State Correctional facility which was approximately two weeks after George Jackson's death. The uprising of New York's Attica State Correctional Facility is known as the most notorious prison riot in American History. During this time New York's Governor Nelson Rockefeller ran the Attica State prison as forced labor camps as well as other state prisons. Attica State Prison during this time also had an all white correctional staff and eighty-five percent of Attica's prisoners were Black and Latino. Working conditions in Attica State Prison were unbearable, prisoners were political, poor and maltreated. Hygienic conditions were very bad and medical care was practically non-existent. Prisoners average pay was 40 cents a day for manufacturing mattresses, shoes and license plates, prisoners never saw a lawyer, were prevented from defending themselves, wer...

The Legalization of Marijuana :: Illegal Drugs Substances Essays

The Legalization of Marijuana The purpose of this paper is to discuss marijuana and compare the issue of legalizing it from both sides. We have two factions fighting each other, those who are pro-marijuana and those who are anti-marijuana. These two factions have been fighting on this issue in the halls of justice for years. Pro marijuana legalization groups such as the Physician's Association for AIDS Care and the National Lymphoma Foundation argue that Marijuana should be legalized in order to treat terminally ill patients. Among them are AIDS victims who find that marijuana stimulates their appetites so they can fight off dangerous emaciation, glaucoma sufferers who said it has prevented them from going blind, and cancer patients for whom it alleviates the severe nausea that often accompanies chemotherapy and sometimes makes lifesaving treatment impossible. Due to all these, lobbying groups which show substantial evidence that marijuana can be used as a prescribed drug. Many advocates who are pro marijuana complain that morphine and cocaine are legal and very dangerous drugs, which brings up the question "why not legalize marijuana as a medical drug" when it is proven safer than cocaine and morphine. Lobbying groups in San Diego, California, unanimously voted to urge president Bill Clinton and congress to end federal restrictions against the use of marijuana for " legitiment medical use". City council women Christine Kehoe said she wanted the city of San Diego "to go on the record we support the medical use of marijuana. Marijuana can be a drug of necessity in the treatment of AIDS, glaucoma, cancer and multiple sclerosis". Many agencies, which are anti marijuana such as, the Drug Enforcement Agency and police departments argue that marijuana shouldn't be legalized. These agencies believe that if marijuana is to become legal, then there will be thousands of more patients using marijuana. Then people will raise the question of "why is marijuana even illegal at all, if its a medicine". The main reason why the Drug Enforcement Agency doesn't want marijuana to be legalized is because their is no hard core evidence that proves marijuana is an effective drug as a medicine. In twenty years of research, there has been no reliable scientific proof that marijuana has any medical value. The American Cancer Society , American Glaucoma Society, the National Multiple Sclerosis Society, the American Academy of Ophthalmology, and the American Medical Association , say that their is no evidence that marijuana is a medicine.

Junk Food Prevalence and Its Physical and Mental Implications

Name: Ali Hussain Al-Attas Date: 15/10/2011 Cause & Effect Junk Food Prevalence and its Physical and Mental Implications Introduction: A study conducted lately, showed that junk food affects the function and structure of the brain which could change peoples’ behavior, especially that of children. By definition, junk food is pre-prepared food that has low nutritional value and is high in calories. The aim of this paper is to explore the causes of junk food prevalence and its physical and mental effects. Paragraph 1: Causes: Abundance and Advertisements:Junk food has become very popular among people owing to its accessibility, taste, cost and strong media advertising. It’s difficult to find a district, or even a street, without a fast-food restaurant. Statistics indicate that the number of these restaurants tripled in the last decade. An example of advertisement is putting surprises, free toys, with every â€Å"happy meal† to attract children. The rise of the numbe r of fast-food restaurant leads to an increase in its physical and mental hazards. Paragraph 2: Effects: Physical Implications:Junk food physical hazards of can be broadly categorized into two groups. The first is the immediate effect, namely, obesity that presents health risks. In 2005, a study conducted by NIH found higher rates of obesity in high schools with nearby fast-food restaurants. According to a study carried out on general education students in Saudi Arabia, the rate of obesity among those who frequently eat fast food is 38. 20%, while the rate is 19. 43% among those eating only one meal a week. Another study revealed that about one out of four (or 23. 6%) of Saudi adults are classified as obese.The second group is the distal effects. Being overweight and can increase the chances of getting chronic illnesses. The OSG pointed out that simply becoming obese, with over 30 BMI, raises the likelihood of developing many diseases including heart attack, stroke and few types of cancer. A 14-year prospective study showed men aged 40 to 65 years with a BMI more than 29 had a 72% increased risk of getting nonfatal or fatal coronary heart disease. Clearly, there are direct and indirect connections between junk food and a number of physical illnesses. Paragraph 3: Effects: Mental Implications:Similarly, Junk food results in emotional issues, such as, hyperactivity, and depression. What it does is that it changes the order of the brain. A recent study, conducted at 2010, revealed that it raises the risk of depression by 55%. Another research, involved 80 participants, showed that a drop in anger, aggression and depression resulted from replacing it with more healthy food. It also affects the educational attainment of students by secreting hormones that cause a partial mind inactivity. From that, it can be inferred that there is a strong link between consuming junk food and several behavioral problems.Conclusion: This paper illustrated the spread of junk food as an important factor for many physical and mental problems. Consuming junk food has direct implications, such as obesity. In addition, it leads indirectly to a number of chronic diseases. Furthermore, it changes peoples’ behavior and causes emotional illnesses e. g. aggression and depression. But it still widely spread because of the strong advertisement and few minor reasons. The awareness of this problem is on the increase, but the danger still exists, and governments and official organizations have to do something to reduce these risks.

Bright and Morning Star Essay

There are certain prevailing themes evident through the duration of the story, like race versus class, and religion versus faith; through these we can see the violence and terror that tear through Sue’s and Johnny Boy’s life and how they confront it. From the start of the story, it is evident that Sue loves her family and even though her and her sons have different beliefs she would do anything to protect them. Sue is a Christian woman, and has been since she was a little girl living and working on a farm learning the songs and meaning of the Lord through her mom. Her sons, however, are not swayed by her religious ideals and instead turn to the Communist Party as their faith, â€Å"She had sought to fill their eyes with her vision, but they would have none of it. And she had wept when they began to boast of the strength shed by a new and terrible vision,† (814). If they had listened to their mom and stuck with Christianity instead of Communism then none of the violence and terror would have been upon them, Sug would not be in jail, Johnny Boy would not have been tortured to death, and Sue need not have watched her sons be imprisoned and tortured then be killed herself. Over time though her beliefs start to change and she sees her sons’ point of view, â€Å"The past and the present would become mixed in her; while toiling under a strange star for a new freedom the old songs would slip from her lips with their beguiling sweetness,† (814). She too wants equality and is proud of her sons for standing up for what they believe in, but is also afraid for them, especially Johnny Boy who is willing to die to protect the Party and its members. During this time period, violence toward black people was common and terribly nasty especially in the South where lynching was common and often a group sport. Like many black people of this time, Sue distrusts most white people, and when hearing there is a leak in the Party she automatically points her finger at the white members. Johnny Boy on the other hand does not, â€Å"Mah, Ah done tol yuh a hundred times Ah can’t see white an Ah can’t see Black. Ah sees rich men an Ah sees po men,† (822). They are both somewhat naive, it is not white versus black and rich versus poor, but rather a combination of the two with shades of gray mixed in, like Reva demonstrates when she sneaks out to warn Sue of the danger coming after Johnny Boy. Of course during this time, almost all southern white folks saw themselves superior to blacks and had no problem distributing harsh punishments, like breaking Johnny Boy’s kneecaps with a crow bar and deafening him. The violence described is so real that their terror is tangible off the paper. By the end of the story, the violence and terror Sue and Johnny Boy had to endure is terribly surreal. Even though they may not believe wholly in the same things, the horror they both confronted came from a combination of race and their beliefs. Wright’s depiction of violence in his use of language is what constellates race, violence, and terror.