Scientific revolution Essay Example for Free

Scientific revolution EssayBetween the years of 1550 to 1750, the Scientific Revolution encouraged new ideas and theories regarding life, humans, and the universe. The great thinkers of this period such(prenominal) as Copernicus, Brahe, Kepler, Galileo, Newton, Bacon, and Decartes all challenged religion and philosophy when they delved into the world of science and logical intellection. Many topics like Nicolaus Copernicus heliocentric view of the universe not only challenged the church, entirely also altered the way people viewed God and their faith.As logical and rational thought started to spread, the use of mathematics to have a better correspondence of things spread as well, resulting in new ideas and views of philosophy. The people soon began to grasp these concepts, which resulted in their questioning of the church and the way they viewed life. Before scientists began looking up into the throw out for answers, the church had provided the people with the knowledge they needed.The Catholic Church had always taught and believed that the earth was the center of the universe and that all things such as the planets, moons, and suns revolved nigh us because God loved us so much that he made us the center of His universe. When Copernicus proposed his hypothesis the idea that the sun, not the earth, was the center of the universe, the church indomitable that the theory was false and they rejected it. Even though they did this, it raised a few questions within the scientific community. Kepler, Brahes assistant, used part of Brahes head for the hills to mathematically substantiate Copernicus theory to be true.Others came forth with findings of their own that also supported Copernicus theory. One of these people was Galileo whose discoveries made Catholic believers question the doctrines of the church. The people wondered to what expiration did their faith answer the questions of the universe. Sir Isaac Newton was able to combine the work of Copernicus, Kepler, and Galileo into one theory that allowed him to believe that you do not need religion to explain the things that pass along on earth, you just need reason. This ultimately drove believers and supporters of the church to rethink their life and what it means to believe in the Catholic faith.As rational thinking became popular, so did new ideas and views about how people saw themselves and the way they lived their lives. More and more scientists and other people used the scientific method and mathematics to prove things for themselves. As their logical thinking increased, their previous concepts soon diminished. Things like the geocentric theory were proven wrong while law of the earth, like the law of gravity, were universe proven true. Often, the church tried to write the scientists off as heretics because of their unorthodox beliefs and because it went against the churchs teachings.The scientists were so curious about the world and the universe around it that they didnt s top they kept making remarkable advances in the society that they lived in. The great scientific and mathematical thinkers of the Scientific Revolution inspired people to change their ways of life and their beliefs. The new view of the universe and its heliocentric nature shifted the faith of devout religious people away from the church. People were encouraged to chink mathematics and literature. Between the years of 1550 and 1750, old religious theories were slowly dismissed as new rational theories and philosophies became popular and reigned true.

ASQ Agile v Waterfall Essay Example for Free

ASQ wide awake v falls Essay waterfall vs. Agile foresee circumspectionLisa Sieverts, PMP, PMI-ACPPhil Ailes, PMI-ACP waterfall vs. Agile formulate circumspectionAgendaWhat is a ProjectOverview tralatitious Project Management Agile Project ManagementThe Differences Product Life Cycle The Teams Requirements WBS/Product cumulate Schedule Risk QualityQA2Lisa Sieverts Phil Ailes1 waterfall vs. Agile Project ManagementWhat is a Project? Temporary Goal Constrained3Lisa Sieverts Phil Ailes waterfall vs. Agile Project ManagementWhat makes projects special? Projects arecharacterized byuncertainty4Lisa Sieverts Phil Ailes2Waterfall vs. Agile Project ManagementTraditional Waterfall Projects Traditional Waterfall Projects Dates from the end of WWII Grew out of Defense industry Based on Deming Cycle of Plan-Do-Check-Act Emphasizes heavy up-front analysis Lots of documentation PMBOK versions 1-4Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementTraditional Waterfall ProjectH ighMediumRequirementsLowoptionalHigh creationMediumLowoptionalHigh maturement MediumLowOptionalHigh testMediumLowOptionalHighDeployMediumLowOptional6Lisa Sieverts Phil Ailes3Waterfall vs. Agile Project ManagementWaterfall Advantages7Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementWaterfall Advantages Established Processes- Project Management Body ofKnowledge Management Controls (Apparent) Predictability Great for low uncertainty/high dependency projects Construction Update of established product Maintenance projects8Lisa Sieverts Phil Ailes4Waterfall vs. Agile Project ManagementWaterfall Disadvantages9Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementWaterfall Disadvantages Sometimes is more about(predicate) the Process than theProduct Keeps the customer at bay by the time they see the end results it may be too late Project teams much become rigid and resistant tochange Those darn users keep changing theirminds. Long product development time10Lis a Sieverts Phil Ailes5Waterfall vs. Agile Project ManagementAgile Project Management The Agile Way Experiments in the 1990s Values self-organizing teams No formal projectmanagement reiterative approach FlexibleLisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementManifestoThe Agile Manifesto for Software Development We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value Individuals and interactions over processes and tools Working software over encyclopaedic documentation Customer collaboration over contract negotiation Responding to change over following a plan That is, while there is value in the items on the right, we value the items on the left more.12Lisa Sieverts Phil Ailes6Waterfall vs. Agile Project ManagementThe Agile WaySprints High Priority Features unifyTestSprints Low Priority FeaturesIntegrateTestIntegrateTestDesignTestTestDevelopIntegrateTestDemo FeedbackDevelopRequirementsTe stTestDevelopSprints Optional Priority FeaturesDemo FeedbackRequirementsDesignTestDesignTestDemo FeedbackDevelopRequirementsTestDemo FeedbackRequirementsDesignTestSprints Medium Priority Features13Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementAgile Advantages14Lisa Sieverts Phil Ailes7Waterfall vs. Agile Project ManagementAgile Advantages Shorter development cycles Customer participates, providing direct feedback Team-ownership developers, testers, analysts andcustomers work together Process encourages and easily adapts to change Improved quality because testing is continuous15Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementAgile Disadvantages16Lisa Sieverts Phil Ailes8Waterfall vs. Agile Project ManagementAgile Disadvantages Lack of established processes Management shelter to change Reduced (apparent) hazardability Requires culture change Its new there isnt a lot to draw upon17Lisa Sieverts Phil AilesWaterfall vs. Agile Project Manage mentProject Life Cycle TraditionalwaterfallInitiatePlanDefineDesignBuildTest Agile Projectsiterative run intoSpeculateExploreAdaptCloseRepeat asnecessary18Lisa Sieverts Phil Ailes9Waterfall vs. Agile Project ManagementThe Team WaterfallSponsorProductManagerProjectManagerThe Team defined roles AgileSponsorProductOwnerScrumMasterThe Team inconstantroles19Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementThe Requirements Waterfall LargeDocument Formal, basedon analysis Performed byBusinessAnalyst endbefore anydevelopmentbegins Agile Small IndexCards User Stories,based onconversation Performed bythe ProductOwner establishedjust in time20Lisa Sieverts Phil Ailes10Waterfall vs. Agile Project ManagementThe Foundation DocumentsWaterfall Work BreakdownStructure c % of Scope21Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementThe Foundation DocumentsAgile The Product BacklogRoman Pichler, Agile Product Management22Lisa Sieverts Phil Ailes11Waterfall vs. Agile Pr oject ManagementThe Schedule Waterfall Built before workbegins End date is often Agile Rebuilt all(prenominal) sprint End date evolvesbased on teamvelocity Focused on nearterm accuracy Emphasizes regulardelivery of workingfeaturespredetermined Strives to predict thefuture Emphasizes deliveryof the entire product23Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementRisk Waterfall Inherently high-riskbased on longproduct cycles Emphasizes theability to predict thefuture Risk Register Agile Inherently low-riskbased on customerfeedback Emphasizesadaptation tochangingsurround Risk Register24Lisa Sieverts Phil Ailes12Waterfall vs. Agile Project ManagementQuality Waterfall Testing is at the end Agile Testing begins beforedevelopmentof the project Testers workseparately fromdevelopers User acceptationoccurs at the end ofthe project Testers anddevelopers worktogethersimultaneously User Acceptanceoccurs at end ofevery sprint25Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementWhats Different? Waterfall Plan all in advance Work BreakdownStructure Functional specs Gantt chart Status reports Deliver at the end Learn at the end equal the plan Manage tasks Agile Plan as you go Product Backlog User stories Release plan Story boards Deliver as you go Learn every sprint Adapt everything Team ownership26Lisa Sieverts Phil Ailes13Waterfall vs. Agile Project ManagementSummary Both Waterfall and Agilehave the same goals Delivering a well-tested product thatsatisfies thecustomer within anefficient time framethat doesnt leavethe team raddled out27Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementQuestions28Lisa Sieverts Phil Ailes14Waterfall vs. Agile Project ManagementThank You29Lisa Sieverts Phil AilesWaterfall vs. Agile Project ManagementContact Us Lisa Sieverts Facilitated Change www.lisasieverts.com 603.762.0235 Phil Ailes Ailes Consulting www.ailes-consulting.com 603.903.705130Lisa Sieverts Phil Ailes15

Improve the World Essay Example for Free

Improve the World EssayWe all want to make the macrocosm a better tooshie, but few of us go beyond this abstract idea to planning for change. Like any goal, it takes thought and determination. You may wonder if you can change the world like the keen leaders in history. Remember that these people started out with dreams, just like you, and worked through insecurities, fear and doubt. Although we do live in a world of reformations as economies develop, trade flourishes and as astounding technological advances be made but our world is still far from being perfect. No matter how many advances argon made in technologies the world will still need some enhancements. Some recent researches have founded out that the more time rolls by the more this world is getting polluted. A social crisis of unprecedented proportions that the whole planet of ours faces today is environmental pollution. Technology gave man sufficient control over his environment yet by our apparently increasing con trol over our environment, we have in fact erred and caused the loss of our control over our environment. Due to the global heating plant and greenhouse gases the world is day by day turning unsafe.We all are living in an insecure environment. Every year thousands of people are killed due to the wars and disputes. Developments in these aspects can improve the world and the lives of the people living in it. If we have in mind of a way how to improve the world and make it a better view to live there can be thousands of things we can do as individuals. As we know that pollution is one of the reasons. We can think of a way to terminate it. Every year thousands of people especially children are influenced by the diseases spreaded in the dirty atmosphere.If we try to reuse, recycle and dispose herd around us the environment can become much cleaner. As far is the wars are concerned we ourselves are behind all the disarray. Following on the values of unity, faith and discipline the worl d can be a serene place to live in. The modern men can shed his prejudices and raving mad notions and eschew war on the realization that all men are brothers. Unless human nature changes, unless there is a change of heart among the leaders of the world as well as the peoples, it is impossible to eliminate the factors that cause war.As far is the development of a mans nature is concernced in mold to make this world a peaceful place education plays an important role in the development of manhood. When literacy rate develops the world itself becomes a better place to live in. According to the Greek philosopher Heraclitus change is the essence of life. The world can be made more perfect if change occurs and this change will but occur if the people living in it stay determined and try to achieve their goals in making the mother Earth a better place to live in.

impact of feminism on fashion

impact of feminist movework forcet on fashionImpact of Feminism on FashionThere has been a heated intervention on the equality of man and woman since a century ago when feminists began to strive for womens bene go bad. Compared to women in nineteenth century, women in this day and age put one across to a greater extent rights and freedom. Women are now more considered to be independent individuals, as long time ago, they were possessions of men. Furthermore, women were compelled to follow every single rules of order from men unconditionally. As an alpha impetus to fashion, feminism, which was mainly formed by three waves, has changed the stereotype significantly and lead to the decrease of restrictions on womens dressing.Feminism encompasses many different theoretical, political and pedantic traditions. At the centre of feminist concerns, however, is the liberation of women from oppressive social practices and ideologies.The first wave of feminist movement dated from nineteenth century to 1940s in United Kingdom and United States. Accompanied by anti-feudal movement, feminism finally became the most indispensable part and the criteria of social revolution.Originally it focused on the packaging of equal contract and property rights for women and the opposition to chattel marriage and ownership of married women (and their children) by their husbands. However, by the end of the nineteenth century, activism focused primarily on gaining political power, particularly the right of womens suffrage. Basically, it was the first time when women have the opportunity to vote. During this wave, World War I took place, which was another cause of changes in womens status. In order to defend national sovereignty, men were conscribed to fight in the battle front. Therefore, women had to do mens physical labour in factory. Females no longer stayed in the house scarcely serving their own family, but also went out working to support the household and their country. Not acci dentally, (see Illus. 1) Coco Chanels simple and practical designs catered to the needs of working women. In her shop, she sold flannel blazers, straight linen skirts, sailor tops, long jersey sweaters and skirt-jacketswhich were inspired by menswear. These convenient clothes enabled women to work with higher efficiency. Chanel used much(prenominal) serviceable materials and relaxed patterns in the design of fashionable daywear for sophisticated urban women, safe in her knowledge of their aspirational and practical qualities. Her accomplishment in fashion helped her situated in the roles of feminist pioneer. Simplicity has become a recognized characteristic of Coco Chanel and affected the fashion trend afterwards. Unfortunately, after the men returned from war when the WWI ended, women were dispatched back to the kitchen.Still, an weighty late stage had been reached, since the induction of women into the war effort initiated the whole process of liberation.Between early 1960s and late 1980s, it was the second-wave feminism. Though after the first-wave feminism women have won over some legal rights, they were still limited and oppressed in working place. Slightly different from the first wave, the second-wave feminism concentrated on issues of historical equality of women such as eliminating discrimination. Feminists went all out marching and protesting in the street. Owing to their hard struggle, females gradually earned some equality in the working place and other aspects of life. In all their achievements, the most remarkable event was the release of some gynocentric legal reforms. Without the legal obstructions to womens personal freedom and master copy achievement, women had a chance to prove themselves to be as capable as men. The 1960s, also called the Sixties, was a decade when tremendous changes happened to fashion. In this era, fashion was influenced by divers(a) factors such as social mobility, daring fashion photography, easier travel abroad, the Vietnam War, new music of the Beatles and their much copied hairstyles, retro military and ethnic clothes, musicals, pop art and contract all played a part. Feminism was absolutely one of the most influential causes of all. Le Smoking (see Illus. 2), designed by Yves Saint Laurent in 1966, is a typical example of impact on fashion by feminism. Yves Saint Laurent wasnt the first person who created trousers for women. However, it was the first of its kind to draw attention in the fashion industry and the public. This innovative creation started androgynous style for women and pantsuits have been popular ever since. Its still one of the favourite outfits of office ladies in contemporary society. The popularity of power suits demonstrates womens liberation and equality between men and women to some extent. Besides, it provides women another choice in their wardrobes and dresses were not the only selection any more. In a word, the appearance of pantsuit is a symbol of women been con sidered to be an independent individuals in workplace. In group of people in younger age, some daring youths were seeking for something new in fashion as restrictions on women reduced. Mary quants miniskirts (see Illus. 3), of which the hemline was set 6 or 7 inches above the knee, fulfilled their needs. It was controversial when it first came into the market, but then more people began to accept it in the mid-1960s and went into the major international trend. Miniskirt was reckoned to be a sign of womens liberation and enabled women to run and show their beauty without limits. The third-wave feminism began in the early 1990s, and the fashion in this decade was casual and comfortable. However, fashion and feminism dont always go hand in hand. The release of womens body didnt go further because every woman wants perfect body for both personal reason and attracting men.Wearing garments that show their nice body makes women feel better, more sightly and sometimes even more confident. Fashion nowadays emphasized on silhouette and only slim and S-shape body is deemed to be beautiful. This brings stress on women and urges them to fit themselves into clothes that might be too tight. After struggling for equality for more than one hundred years, phenomena of inequality have decreased remarkably. But men have been in the dominant position for the majority of time in history. Reforms in laws are definitely not enough to change the status. To gain real equality, male chauvinism should be eliminated entirely. Anyway, its still a long way to go to have final equality of men and women.

Annotated Bibliography on Tacrine

Annotated Bibliography on TacrineSathyan G et al (1995) studied the effect of resolvents such as water, propylene glycol and ethanol and their mixtures for transdermal medicate pitch on in vitro permeation of tacrine by means of skunk and human skin. Largest flux and permeability were observed from ethanol-propylene glycol and water-ethanol binary mixtures, respectively. Excellent correlation betwixt the rat and human skin data was observed. The formulations were found to be devoid of skin irritancy property. Ethanol-propylene glycol (11) mixture with a flux of 98 g/cm2 through rat skin was found to be a promising solvent system for the transdermal delivery of Tacrine.Yanq Q et al (2001) formulated microparticles of tacrine exploitation poly (D,L-lactide-co-glycolide) (PLG) by solvent vaporization technique. Effect of formulation variables on Encapsulation efficiency and release was studied. Results showed an increase in encapsulation efficiency by 10 times and decrease in p ost of release when molecular weight of polymer was changed from 8,000to 59,000 and 155,000 The study indicated that tacrine microparticles have a strong potential for long term treatment of Alzheimers disease.Kankkunen T et al (2002) investigated the iontophoretic delivery of Tacrine on 10 healthy adult volunteers by comparing a commercial LOGEL electrode with an ion exchange fibre formulation. Clinically significant plasma concentrations 21.3+5.9 ng/ml was achieved by commercial system whereas 14.9+2.6 ng/ml was achieved through ion exchange fibre system. The study showed that iontophoretic delivery of Tacrine is safe .Serum alanine transferase levels Jogani VV et al (2008) prepared and characterized mucoadhesive microemulsion of tacrine by the titration system for brain targeting for the treatment of Alzheimers disease. Selective nose to brain transport was confirmed by lower Tmax values (60 min) with intranasal administration than 120 min with intravenous administration. The brain bioavailability of tacrine afterwards giving optimized formulation was 2 times more than obtained with intranasal tacrine solution Scintigraphy study in rabbits showed more uptake of Tacrine in brain after intranasal administration. The results indicated better, quicker transport of tacrine in scopolamine-induced amnesic mice brain and rapid regain of memory loss after intranasal administration. Hence, results suggested that intranasal tacrine delivery hold promising in treating Alzheimers disease.Wilson B et al (2010) prepared Tacrine-loaded chitosan nanoparticles by spontaneous emulsification method. The particles were characterized for size, zeta potential, drug-loading capacity and in vitro release. Mean particle size for drug-to-polymer ratio 11 was found to be 41 7 nm with average zeta potential of +34.7 1.5 mV. The release of tacrine from nanoparticles ranged from 83.04% 1.41% to 94.64% 0.84% for 12 hours depending on the drug-to-polymer ratio. In vitro release st udies showed an initial burst of 30 minutes followed by unremitting and slow release of the drug. The release of drug from nanoparticles was diffusion-controlled, following Fickian mechanism. Controlled release characteristics suggested prolonged residence time which could improve the bioavailability of tacrine in the brain.Luppi B et al (2011) prepared white nanoparticles of Tacrine hydrochloride with beta cyclodextrin, hydroxypropyl beta cyclodextrin and sulphobutylether beta cyclodextrin using coacervation method and thermal cross-linking. Prepared nanoparticles were then soaked in solutions of tacrine hydrochloride and lyophilized for effective drug loading. Evaluation results showed that nanoparticles had a spherical shape with negative charge and mean size .Dixit S et al (2013) formulated mouth dissolving tablets of Tacrine hydrochloride by direct compression using different superdisintegrants. Results indicated that mouth dissolving tablets showed acceptable hardness, friab ility, mechanical strength and weight uniformity. The optimized formulation disintegrated in less than 1 minute in mouth and released 98% of Tacrine within 14 minutes. The study reflected the potential of mouth dissolving tablet of Tacrine for quick absorption, improvement in bioavailability, increased patient compliance especially in patients with clog in swallowing.Corace G et al (2014) developed liposomes delivery of tacrine hydrochloride by nasal route using cholesterol, phosphatidylcholine, a-tocopherol and/or Omega3 fatty acids by reverse phase evaporation technique followed by membrane filter extrusion. Results reflected that prepare d liposome formulations had a mean diameter varying from 175nm to 219nm with polydispersity index Haughey DB et al(1994) developed a reversed-phase superior liquid chromatographic method(RPHPLC) with fluorescence contracting for the analysis of Tacrine and 1-hydroxy-, 2-hydroxy-, and 4-hydroxytacrine (metabolites of Tacrine) in human plasma. The alkalinized samples of human plasma were extracted with a mixture of 9010%v/v of anaesthetize and l-propanol. Calibration curves were constructed for clinically significant concentrations(5 to 30 ng/ml) for all the analytes. The method was found to be precise and spotless. The developed method was sensitive enough for the end of tacrine and its metabolites after Cognex (40 mg single dose) was administered orally to normal volunteers.Hansen LL et al (1998) developed and validated a method for simultaneous estimation of tacrine and its metabolites, 1-hydroxytacrine , 2-hydroxytacrine and 4-hydroxytacrine in human plasma and urine .The method involved one-step liquidliquid extraction with ethyl acetate. Determination was done by isocratic, reversed-phase high-performance liquid chromatography using fluorescence detection (excitation 330 nm and emission 365 nm).The developed method demonstrated simplicity , precision, accuracy and sensitivity with limit of detection as 0.5 nM fo r 2-hydroxytacrine and 4-hydroxytacrine, 2 nM for 1-hydroxytacrine and tacrine in plasma. Mean recovery ranged from 84 to 105% for tacrine and its metabolites in plasma.Aparico I et al (1998) developed a spectrofluorimetric method to estimate tacrine in human serum and pharmaceuticals. The fluorimetric method allowed the determination of Tacrine in the range of 170 ng /ml in aqueous solutions of acetic acidsodium acetate buffer (pH 5.6) with (excitation wavelength of 242 nm and emission wavelength of 362 nm.Chollet DF et al (2000) developed a high-performance liquid chromatography (HPLC) assay method for therapeutic monitoring of Tacrine. The method was based on simple protein rush by acetonitrile or cold methanol followed by isocratic separation on a CN column eluted in reversed-phase mode. Developed method was found to be precise, robust, accurate and suitable which was demonstrated by analyzing more than 1,000 plasma samples from patients with Alzheimer disease .Ortuo JA et al ( 2007) developed a flow-injection pulse amperometric method for estimation of Tacrine on the home of ion transfer through a plasticized poly(vinyl chloride) (PVC) membrane using a four-electrode potentiostat with ohmic drop compensation. Lnear relationship between peak height and concentration of tacrine was found up to 410-5M .Limit of detection was found to be 110-7M. The method was found to be linear, reproducible, specific and repeatable.Qian S et al (2012) developed an assay for simultaneous determination of Tacrine and its metabolites in rat plasma and brain tissue. The analytes along with internal standard were extracted from plasma of rat or tissue homogenate of brain by liquid-liquid extraction with the help of ethyl acetate. The separation was done on Thermo Hypersil BDS C18 column using mobile phase of acetonitrile and ammonium formate-triethylamine (pH 4.0) with fluorescence detection. Percentage recovery varied from 82.1% to 93.2% in h rat plasmas and brain tissue. The developed method was found to be simple, sensitive and reproducible procedure for the estimation of Tacrine and its metabolites in rats after oral administration.

Simulation of the ALOHA protocol

Simulation of the ciao protocolAbstract-The present essay is a tutorial on the OMNeT++ pretense environment, through the analysis of the cognise ciao protocol. The model implements the ciao random price of admission protocol on the Link layer, and simulates a host to server instant hand out. aloha is rather plain soon enough convenient to demonstrate the potential of OMNeT++ in simulating radiocommunication protocols. The final part evaluates the pure and the slotted ALOHA variations, in regard to the theoretical models.IntroductionOMNeT++ is a distinct typeface pretence (DES) environment, developed by Andras Varga as public source, and is accompanied by Academic Public License, which means that it is free for nonprofit academic use. The target behind OMNeT++ was the development of an open source generic poser environment, not exclusively dedicated to network simulations as the more than known ns-2, or the commercialized Opnet. The environment offers instead, a generic and flexible platform to develop simulation positionworks dedicated to complex IT systems, as wireless and sensor networks, the patternic IP and IPv6 stacks, queuing networks, ocular networks and various hardw atomic number 18 architectures.Typical example of a framework that provides simulation components for IP, TCP, UDP, Ethernet and MPLS, is the INET Framework and the MiXiM, which is an aggregation of several frameworks for mobile and wireless simulations. The OMNeT++ ver. 4.0 is built on the known Eclipse CDT ver. 5.0, and uses most of its resources. It is offered for Windows and Linux operating systems. The core of the models is coded in C++, in Linux uses the gcc compiler and in Windows uses the MinGW port for the gcc suite. There is a commercial version called OMNEST, with no signifi can buoyt accessories than the open version, except the optional use of the native Visual C++ compiler for the Windows platform.The ALOHA protocol was one of the oldest random access protocol s, invented by Norm Abramson in 1969. The first wireless network, implementing packet switching over radio, used the pure ALOHA variation, have initially established in Hawaii. later(prenominal) Abramson interfaced the ALOHAnet with the ARPAnet, the primitive form of internet. The ALOHA have inspired the creation of CSMA/CD and the birth of Ethernet. Finally, the random access protocol has evolved to contemporary CSMA/CA, the MAC layer of Wi-Fi. The slotted ALOHA and the later pure ALOHA have unproblematic implementations, portion for simulation. It uses only the host to server broadcast instant, but is adequate to calculate the supreme pass on capacity and demonstrate some opposite interesting attributes, as well.OMNeT++ DESCRIPTIONThe Structure of ModelsOMNeT++ is based on C++ programming and fol low-downs the object-oriented approach with classes and class instances, the so-called objects. The simulation model consists of modules, which communicate by message passing. The core element is the simple module, which is written in C++, and constitutes an instance of a module slip from the simulation class library. The adjacent structural element in the hierarchy is the entangled model, which is formed from simple modules or other compound models. E very module, simple or compound, has ports to communicate with the external environment, called furnish. Gates could be bidirectional or could be restricted to input or output. Modules are connected through their gates via connections and they communicate by exchanging messages, via these connections.The block diagram in Fig. 1 depicts the internal module structure gibe to the declare hierarchy, in OMNeT++. The connections are limited indoors the module range but the message exchange can be established across hierarchy levels. This is applicable in the case of modeling wireless systems and the simulation of ALOHA institutionalizes will make use of it. Otherwise, messages are traveling through the chain of connections. Modules have parameters, which are used to pass initialisation data during the initiation of the simulation. The compound models can pass parameters to the contained sub-modules. The final model which contains the aggregate of the modules is called network model, is represented as a class and each simulation run is executed on an instance of this class.The NED languageThe structure of the simulation in OMNeT++ is based on the network interpretation language (NED). The NED includes declarations for the simple modules and definitions for the compound modules and the network model. The language programming is accomplished by the integrated graphic editor, as shown in Fig. 2 or the text editor, as shown in Fig. 3. both(prenominal) editors are producing equivalent code, and the coder can switch from one another without any derogation.The programming modelThe typical code development includes the hobby stairs The programmer creates the network model, by creating the ap propriate network_name.ned cross-file, using the IDE. The NED file describes the network name and the topology, which are the names of the sub-modules, simples and compounds. Every sub-module should have its own module_name.ned file, which includes the parameter declarations and other meta-data. As mentioned, the demeanour of every(prenominal) simple module is expressed in C++, so there should be two specific files, the module_name.cc and the module_name.h, for every simple module. These files are compiled during simulation execution by the supporting C++ compiler, and linked with the simulation kernel and libraries.The programmer usually tests the behavior of the simulation model according to different inputs. These could be entered manually by the user, during simulation execution, or could be included in a configuration file. Generally, there is a special caseful of file the omnetpp.ini that contains these parameters and the rest of the building blocks, to support user intera ction. The IDE includes an editor for the initialization files, which can switch between form view, as shown in Fig. 4, and source view, as shown in Fig. 5. The two fields are equivalent.There are two fundamental methods to develop C++ code for programming the simple module behavior The co-routine based and the event processing function. In the first approach, every module executes its own threat of code, which is activated every judgment of conviction it receives a message from the simulation kernel. In the last approach, the simulation kernel calls the module function, having the specific message as argument. Prior to main() function execution, an initialization function declares variables and objects and before program termination, a finalization function saves the data logged during simulation, and produces histograms.OMNeT++ Architecture and PotentialityThe next Fig. 6 presents the internal logic structure of OMNeT++. The first block is the model component library, which the programmer develops in C++, and contains the compiled code of simple and compound modules. The simulation kernel and the class library (SIM) instantiates the modules and build the concrete simulation model. The user interface libraries (Envir and Cmdenv or Tkenv) provide the simulation environment, which defines the source of input data, the sink of simulation results and the debugging information. It controls the simulation execution, visualization and animation.Cmdenv provides only command line and text mode input-output, and it is more appropriate for batch simulations. Tkenv is the graphical user interface (GUI) of OMNeT++. It provides automatic animation, module output windows and object inspectors. The following Fig. 7 depicts an active simulation output through OMNeT++/Tkenv.OMNeT++ includes very powerful tools to visualize the interaction among modules. A sequence chart diagram provides a way to inspect the timing of the events during simulation by extracting data from an ev ent log file. During the finalization routine, the logged data are saved to specific result files, the vectors in network_name.vec and the scalars in network_name.sca files, respectively. For the result analysis, OMNeT++ produces the analysis file network_name.anf, which contains aggregated data in vectors and scalars plus any histograms, created during the final stage. All the types of data can be further processed by using pattern rules, in datasets and charts section, to produced advanced charts and graphs. In the ALOHA simulation most of the available choices are used for demonstration. aloha SimulationBackground TheoryThe slotted ALOHA is the most simple random access protocol. The transfer station always broadcasts at the full rate R of the channel. The transmission initiates at the first-class honours degree of the slot, which is common for the aggregate of the displace. If two or more stations transmit simultaneously, then the condition is called collision and all the sta tions involved, after a random metre different for each, retransmit the frame until thriving delivery. The procedure is presented at the following figureThe slotted ALOHA protocol allows each station to transmitat at the channels full speed R, but requires slots to be synchronized in all the stations, something not nessesary for the unslotted or pure ALOHA. The following assumtions are made to simplify simulationThe source generates single frames of length L bits. The inter-arrival times between frames follow exponential distribution. If R bps is the capacity of the wireless link then the slot time is set equal to the transmission time of each frame, which is tframe=LR sec.All nodes are synchronized and transmit frames only at the beginning of a slot.If a node has a new frame to send, it waits until the beginning of the next slot.If two or more frames collide, then their hosts retransmit after random time, following exponential distribution.If there is no collision, then the nod e transmits its next frame following exponential distribution.I define N the number of stations operating the slotted ALOHA protocol and p the probability of each station to transmit in the next slot. The probability for the same station to do not transmit in the next slot is then 1-p, and for the rest of the stations is 1-pN-1. Therefore, the probability for a station to have a successful transmission during the next slot is to transmit and the rest of the stations to do not transmit, so it is p1-pN-1, and because there are N stations, the probability that an arbitrary node has a successful transmission is Np1-pN-1.A slot where a single station transmits is called a successful slot. The efficiency of slotted ALOHA is defined as the long run fraction of successful slots, which isEp=Np1-pN-1 (1)To find the supreme efficiency, we seek p* that maximizes (1). ThenEp=N1-pN-1-NpN-11-pN-2=N1-pN-21-p-pN-1If Ep=0 then p*=1N . Using this value, the maximum efficiency isEp*=N1N1-1NN-1=1-1NN-1 =1-1NN1-1N (2)For a large number of active stations, the maximum efficiency accrues from (2) as N approaches infinitylimNEp*=limN1-1NNlimN1-1N=1e1=1e=0.368 (3)From (3), the maximum efficiency of slotted ALOHA is 0.368 or 36.8%The unslotted version or pure ALOHA protocol does not have the restriction of slot synchronizing, and the station is able to broadcast when a new frame is available. So pure ALOHA is a full-decentralized random access protocol. When a transmitting station detects a collision, after complete the transmission, it retransmits the frame with probability p. If it chooses to postpone the transmission for a single frame transmission period tframe=LR sec, then the probability is (1-p). The figure below depicts transmissions and collisions in the unslotted channel.The maximum efficiency of pure ALOHA protocol is calculated similarly as the slotted ALOHA. The only difference here is that the rest of the stations should have not begun transmitting before and should not b egin during the broadcast of the assumption station. The probability that the rest of the stations remain idle is 1-pN-1 and the probability that they remain idle is 1-pN-1 again. Therefore, the probability that the given station will have a successful transmission is p1-p2N-1.Again, we seek the value of p* that maximizes (4), which is the probability of successful transmission for the sum of the N stations.Ep=Np1-p2N-1 (4)Ep=N1-p2N-2-Np2N-11-p2N-3=N1-p2N-31-p-p2N-1If Ep=0 then p*=12N-1 . Using this value the maximum efficiency isEp*=N2N-11-12N-12N-1 (5)From (5), the maximum efficiency accrues as N approaches infinity, which islimNEp*=121e=12e (6)From (6) I assume that the maximum efficiency, for the pure ALOHA protocol, is 0.184 or 18.39%, the half of slotted ALOHA.Another useful diagram is in Fig. 10. It depicts the apparent superiority of slotted ALOHA over the pure ALOHA protocol, despite the limitations that turn it to non-functional. The normalized intact concern is the agg regate traffic, which generated by the source of the station, divided by the channel capacity R and the normalized throughput ? is the average successful traffic (non-collided) divided by R. The slotted ALOHA achieves double throughput than the pure ALOHA and achieves its maximum efficiency when the generated traffic rate equals the channels capacity R. The pure ALOHA although, achieves its maximum efficiency when the generated traffic equals to R/2.Model DevelopmentNED languageThe following paragraphs describe the process of creating a functional model for the simulation of ALOHA protocol in OMNeT++. The object of simulation is to study the behavior of the ALOHA model and to confirm the theoretical values of maximum efficiency for pure and slotted ALOHA. The ALOHA random access protocol is associate based and does not use a server-client architecture. It is convenient to study the effect of collisions and random retransmissions only in the case when one host is receiving (becomes server) and the rest of the hosts are transmitting.The first step is to develop the NED code that describes the network Aloha. The following Aloha.ned file creates the Aloha network, which consist of simple modules, one called server and a number of hosts, equal to num legionss parameter. The txRate defines the transmission rate R, of the wireless channel, and slotTime defines the type of protocol. Zero means pure ALOHA and 100ms defines the slot time length. The parameter display selects a background image, interpreted from the library.network Aloha parameters int numHosts // number of hosts double txRate unit(bps) // transmission rate double slotTime unit(ms)// zero means no slots (pure Aloha) display(bgi=background/terrain) submodules server server hostnumHosts Host txRate = txRate slotTime = slotTime The following Server.ned file describes the servers simple module. It debauchs an image for the server icon and defines a gate of input type (in), with which it is not necessary t o establish a connection. It can receive a message directly from a host via directIn, something that is usual to wireless simulations.simple Server parameters display(i=device/antennatower_l) gates input in directInThe following Host.ned describes the hosts simple module. It loads a set of parameters from the omnetpp.ini file, the radioDelay, which is the propagation delay over the radio link, pkLenBits, which is the length of the frame, and iaTime, which is the random inter-arrival time, following exponential distribution. The rest of the parameters, txRate and slotTime, are sozzled in Aloha.ned, during sub-module instantiation.simple Host parameters double txRate unit(bps) // transmission rate double radioDelay unit(s)// propagation delay of radio link volatile int pkLenBits unit(b) // packet length in bits volatile double iaTime unit(s) // packet interarrival time double slotTime unit(s) // zero means no slots (pure Aloha) display(i=device/pc_s)ConfigurationThe most critical fil e is the configuration file omnetpp.ini. It stores the values of the parameters that are loaded in the NED parameter fields. When declaring on the General field that Aloha.slotTime=0, is presets globally the pure ALOHA protocol. Similarly, the Aloha.numHosts=20 defines the number of hosts to be 20, the Aloha.txRate=9.6kbps defines the R to be 9600bps. The last definitions load the parameters of Aloha model and consequently the parameters of the simple modules that Aloha model controls, which are the server and the host modules. The definitions Aloha.host*.pkLenBits=952b and Aloha.host*.radioDelay=10ms load directly the parameters pk.LenBits and radioDelay on every host submodule, respectively.Generalnetwork = Alohadebug-on-errors = truerecord-eventlog = trueAloha.numHosts = 20Aloha.slotTime = 0 no slotsAloha.txRate = 9.6KbpsAloha.host*.pkLenBits = 952b =119 bytes, so that (with +1 byte guard) slotTime is a nice round numberAloha.host*.radioDelay = 10msConfig PureAloha1description = pure Aloha, overloaded too frequent transmissions result in high collision rate and low channel utilizationAloha.host*.iaTime = exponential(2s)Config PureAloha2description = pure Aloha, best load near optimal load, channel utilization is near theoretical maximum 1/2eAloha.host*.iaTime = exponential(6s)Config PureAloha3description = pure Aloha, low traffic very low traffic results in channel being idle most of the timeAloha.host*.iaTime = exponential(30s)Config PureAlohaExperimentdescription = Experimental mutliparameter demostrationrepeat = 2sim-time-limit = 90min**.vector-recording = falseAloha.numHosts = $numHosts=10,15,20Aloha.host*.iaTime = exponential($mean=1,2,3,4,5..9 step 2s)Config SlottedAloha1description = slotted Aloha, overloaded slotTime = pkLen/txRate = 960/9600 = 0.1sAloha.slotTime = 100ms too frequent transmissions result in high collision rate and low channel utilizationAloha.host*.iaTime = exponential(0.5s)Config SlottedAloha2description = slotted Aloha, optimal load slotTime = pkLen/txRate = 960/9600 = 0.1sAloha.slotTime = 100ms near optimal load, channel utilization is near theoretical maximum 1/eAloha.host*.iaTime = exponential(2s)Config SlottedAloha3description = slotted Aloha, low traffic slotTime = pkLen/txRate = 960/9600 = 0.1sAloha.slotTime = 100ms very low traffic results in channel being idle most of the timeAloha.host*.iaTime = exponential(20s)A selection of the SlottedAloha2 configuration overrides the value of slotTime with Aloha.host*.slotTime=100ms, which fixes the slotted ALOHA protocol with slot time to 100ms. The Aloha.host*.iaTime=exponential(2s) sets the frame inter-arrival time on every host to follow exponential distribution, with mean time equals to 2 seconds.The Config option PureAlohaExperiment exploits the OMNeTs capabilities of organizing different experiments with simple repetition declarations. The statement Aloha.numHosts=$numHosts=10,15,20 declares common chord (3) repetitions having 10, 1 and 20 hosts respec tively.The statement Aloha.host*.iaTime=exponential($mean=1,2,3,4,5..9 step 2s) declares seven (7) repetitions, with interarrival times equal to exponential distribution and means, 1, 2 ,3, 4, 5, 7 and 9, respectively. The repeat=2 statement doubles the number of runs, so finally the available choices will be 2x3x7=42 from 0 to 41 optional runs. The statement sim-time-limit=90min constrains the simulation time to 90 minutes.C++ model codingThe simple modules Host and Server are based on C++ programming. The relevant host.cc, host.h, server.cc and server.h, which are included merely in the appendix section, implement the model behavior during simulation by exchanging messages directly one-another or with the simulation kernel. The following Fig. 11 is a design- level class diagram, describing the basic relationships among network module Aloha and simple modules, Host and Server. The two last, inherit from cSimpleModule simulation class library, and redefine the basic methods initial ize(), handleMessage(), activity() and finish(), according to the desired function.The Aloha network model comprises of several Host objects and one Server, so it keeps an aggregation association with Host and Server classes. It passes also to them some parameter values, some declared in the omnetpp.ini file and some taken from user dialog form. The Host module keeps an one-way association with Server because every Host declares a Server object in the attribute field, in order to send a direct message (pk) later, by calling the sendDirect() function. The scheduleAt() function programs the kernel to send the Host an endTxEvent message when the transmission ends. This is represented by the self-association. Similarly, the Server module programs the kernel to send the Server an endRxEvent, when the reception of the message sent from Host finishes, and is represented as the self-association.The module code is cited commented in the appendix. Here, I will explain the finish() function of the server module, because it creates the result reports, necessary for the exploitation of the simulation.void Serverfinish() EV

Religion and Politics Essay examples -- Papers Church State Separation

Religion and Politics Both liberals and conservativists put one over become quite adept at mixing religion and politics in our current society. One also continues to observe an ongoing practice of civil religion demonstrated by presidents and office-seekers on twain the left and right. Generally, the leftist merger of religion and politics has received greater social acceptability because it has been cloaked in such rights causes as civil rights, womens rights, or economic rights (the social distri moreoverion of wealth). The advocating of these rights issues have provided an appearance of transcending religion, keeping the left relatively free from criticism of any church and state overlap. delivery boyian Conservatives, however, have found it more difficult to reasonably combine tru stingness and politics because they have more overtly recognized that their political positions are grounded on faith assumptions. This has resulted in numerous attacks by both non-Christians and Christians alike against the conservative attempt to merge religion and politics. Three arguments have been used most frequently against the conservative mixture of religion and politics. In what follows each of these arguments is stated and then refuted. The first argument is that politics is too worldly. The essence of the argument is that politics is part of this worlds system, and Christ clearly taught His followers to love not the world, and to flee from worldly activities. There is a danger of becoming caught up in th... ...hermore, in the Bible in that location is much political activity by Gods servants. The judges and kings ruled under God. The prophets and Moses were quite political. Daniel served in the civil governments of Babylon and Persia. Joseph g overned in Egypt. The Apostles spoke of following Gods rules rather than mens. In conclusion, to be obedient to Christ requires political activity. Jesus is quite clear about the need to overcome social injustices. If Christ tells us to confront the forces of evil, but society tells us not to, and even makes a law against bringing religion into politics, then who should we follow, the state or Christ? In the broadest sense, we are called to political activity because we are responsible to apply Christian principles and standards to all areas of our society, and politics is one of these areas.