General essay
Wednesday, September 2, 2020
The Hobbit Essays (578 words) - The Hobbit, New Zealand Films
The Hobbit The Hobbit recounts to the tale of an agreeable, cordial animal named Bilbo Baggins. Bilbo, as most hobbits, is like a human, yet about a large portion of the size, and substantially more nible in light of the fact that they have rugged bottoms on thier feet, and not close to as noisy. Bilbo becomes involved with secretive issues a lot more noteworthy than his own hobbit-life issues when, at the proposal of a strange old wizard named Gandalf, he is employed as a thief by a gathering of dwarves. These dwarves, drove by Thorin Oakenshield, child of Throror, child of Thrain are heading off to the Lonely Mountain in the East to recover their family's enormous fortune from the extraordinary mythical serpent Smaug who lives somewhere down in the dishes of the desolate mountain. En route, the organization stumbles into difficulty with trolls who live in the cloudy mountains, arachnids who live in Mirkwood woodland, and other damaging and destructive animals, and they regularly get away from simply because of the help of Gandalf and other great animals they meet. Bilbo substantiates himself fundamental to the journey, sparing the dwarves on numerous events with his valor and aptitude. His prosperity is somewhat because of an enchantment ring that he takes from an odd, dim animal named Gollum, who lives in the damp, dull caverns underneath the Misty Mountains. Gollum is sticky and foul and he alludes to his ring as my valuable. Bilbo even figures out how to find Smaug's shaky area, the exposed region under his ear, which permits the monster to be executed and the fortune separated. Be that as it may, the dwarves can't appreciate the gold alone, since it baits people and mythical beings, some of whom have a simply guarantee to a segment of it. Thorin's reluctance to share the fortune nearly prompts war between the dwarves and the mythical beings and people, yet rather war is endless supply of them by the trolls and wargs (wild wolves). All the great races(dwarfs, men, my thical beings, falcons, and Dain's officers) are consequently compelled to join against their shared adversaries. They prevail with regards to overcoming the shrewd animals, yet at the expense of the life of Thorin and numerous others. After the fight, the great races appreciate the fortune in harmony instead of battling about it. Bilbo, exhausted however glad to have had an impact in extraordinary issues, comes back to his peaceful home at Bag End in the Shire. As a result of his unhobbit-like undertakings, he is never truly acknowledged go into the network of Hobbiton. In spite of the fact that Tolkien's reality is one of imagination, he structured it to mirror certain certainties about this present reality. The Hobbit tends to the issue of determing the correct route for a hobbit to live, not what society advises us to do. Would it be advisable for him to or she fret about extraordinary deeds and wars, and hazard losing the modest point of view managed by the straightforward life ? Or then again should the normal individual never look outside their own calm presence, and hazard disregarding the bigger viewpoint that may have permitted him to do extraordinary things for the benefit of everyone? Reality that rises up out of The Hobbit is that, on the off chance that one is approached to have an influence in incredible issues - as we as a whole seem to be, in any event as per Tolkien's Christian point of view - at that point one ought not avoid one's obligation. To play out that obligation well, be that as it may, one should never dismiss one's own inconsequentiality in the bigger plan of things, nor lose regard for the estimation of the basic life. Book Reports
Saturday, August 22, 2020
Altius Golf free essay sample
Altius Golf is an organization head in golf balls, it has been the market chief of golf balls for an exceptionally prolonged stretch of time, but since of the worldwide downturn, its CEO and its head showcasing official are attempting to build up another system by presenting a ball that is evaluated over 40% underneath the companyââ¬â¢s leader Victor TX line and it would be sold principally through the ââ¬Å"off-courseâ⬠channel, keeping it out of the most premium ââ¬Å"on-courseâ⬠retail outlets. Just two executives saw the move well, concurring that it was the correct technique to address the more extensive development difficulties in the golf business. The other five weren. t glad at all with the execution of Elevate, the technique, voicing worries that the Elevate system would harm the brand, subvert the valuing engineering, and hinder edges forever. One of the principle realities to actualize another methodology is to keep an eye out the business patterns. We will compose a custom exposition test on Altius Golf or then again any comparative theme explicitly for you Don't WasteYour Time Recruit WRITER Just 13.90/page The most stressing pattern for the golf business, was declining enthusiasm for the game in the U. S. This was reflected in both all out golf players, and in level of commitment, as estimated by recurrence of play. Additionally the interest in green land and advancement fell over 40% . As all out golf players and their spending fell, retail outlets likewise shut at a disturbing rate, with almost 25% of stores shutting in the years quickly following the downturn. So the downturn quickened longer-term slants in golf retailing. Customer considers indicated that significant expenses, absence of time, and the trouble of the game were the main purposes behind not playing golf and the USGA knew about this negative patterns so its endeavors were centered around making golf increasingly accesible; in light of this two golf balls makers, Primiera and Meridian, exhibited the possibility to make the game progressively available, particularly to new and recreational golf players, that shows that the world in changing so if Altius Golf need to keep up being the markt pioneer it needs to make a few moves, one of them is confronting its new rivals. Primiera started holding custom ball-fitting meetings around the nation and Meridian went above and beyond in making golf simpler and progressively fun: promoting non-acclimating balls with attributes outside the USGAââ¬â¢s parameters. Then again, Evelyn Gracie, CEO of Altius Golf, and Austin Kai, the head promoting official, needed to manage the client inclinations, so to meet those inclinations Altiusââ¬â¢s made a customer examine. This ongoing shopper look into had been uncovering. The brand stayed esteemed and almost all golf players, including the individuals who utilized different balls, saw both the brand and the product offering decidedly. the brand impression of contenders, including Bantam, Carlsbad, and Premiera, had improved; Altiusââ¬â¢s lead in brand quality had declined humbly, and these realities were trailed by other negative signs, the study recommended that a bigger number of customers than before were presently open to taking a stab at contending golf balls. In view of the overview, Austin felt that Elevate was the most ideal approach to make sure about the companyââ¬â¢s longer-term initiative position and Evelyn Gracie accepted that disregarding the effective invasions of Altiusââ¬â¢ rivalry was a losing suggestion and securing the companyââ¬â¢s advertise administration required another methodology. Issue IDENTIFICATION Main issues that Altius needs to manage: 1. Worldwide downturn. The economy is as yet managing the worldwide downturn since 2008, so building up another methodology/item takes additionally its dangers dependent on the economy issues that we are as yet confronting. Before 2008, one out of each two golf balls sold in the U. S. was an Altius ball, and the organization had represented about 60% of industry incomes. These days Altius Golf is still te showcase pioneer yet the most ideal approach to confront an enonomic downturn is through advancement, presenting another item would be the response to manage this downturn. 2. New contenders. Altius Golf has been the market head for quite a while however new contenders like Meridian and Primiera are dominating. To confront this new contenders Altius must make a move actualizing another methodology, fabricating an upper hand over its rivals. In spite of the fact that its still the market chief on golf balls, the world is continually changing so it must make a move. 3. Clients. The organization fragmented momentum Altius buyers into three classes by a client investigate: supporters, devotees, and brand rationalists. The study proposed that a bigger number of customers than before were presently open to having a go at contending golf balls; explicitly, there were altogether more ââ¬Å"agnosticsâ⬠than previously. In view of the overview: AGNOSTICS: medium high to exceptionally high difficult another Brand. (17%) Casual or potentially inconsistent golf player Bound to be a tenderfoot Price-touchy and prone to buy on advancement ENTHUSIASTS: medium to high difficult another Brand. (15%) Moderate recurrence golf player Includes the two fledglings and experienced players, however prone to be ââ¬Å"seriousâ⬠(e. g. taking exercises, rehearsing at driving extent) Interested in ââ¬Å"bestâ⬠gear innovation, yet moderate value affectability 4. Cost. Altiu? s costs are a lot higher contrasted with its rivals, and dependent on the ongoing study that it has made just one gathering of clients are not value touchy. To confront this issues Altius Golf should bring down its costs or present another item with a lower cost to meet the desires for those clients. CASE ANALYSIS Golf is a multi-billion dollar industry that is demonstrating a development in prevalence because of media consideration on rising youthful stars of the game. Various golf items are required and offered to the a great many customers who play this game every year. Due to the huge market which exist, there is solid rivalry between gear creators to get their items sold. Of the hardware that is expected to play a series of golf, clubs and balls are the most basic. All the more remarkably is the way that clubs have a more drawn out useable life than golf balls. New golf balls might be required each time a golf player goes to the course to play a round. This is on the grounds that balls get lost or scraped during play. The high deals turnover which exists with golf balls makes this item appealing to athletic gear makers. Altius Golf might be the unmistakable pioneer in the baseball showcase regardless of the way that there has been a decrease in the measure of golf players and a drop in deals following a monetary emergency. Altius Golf despite everything kept up its great situation in the market by presenting ages of more elevated level, top quality golf balls that permit their customers to duplicate proficient golfers. The business endured a misfortune as a result of rivalry who had been chopping the costs down and the Chief Executive Officer truly needs to present a new program called Elevate to cultivate another age of golf players. With the presentation of Elevate, Altius Golf will present a ball thatââ¬â¢s smoother and better to drive for significant distances and give it at a cost 40% underneath the businessââ¬â¢s leader item. Raise will without a doubt be accessible through ââ¬Å"off the courseâ⬠channels such as golf claim to fame stores and enormous box retailers as opposed to ââ¬Å"on the courseâ⬠proficient shops where in reality Altius Golf sells its items and administrations. The governing body is partitioned on whether to go with this choice or against it. Just two of them bolster this choice, the others believe that the Elevate procedure would harm the brand, sabotage the estimating engineering, and impede edges for all time. Altius Golf can beat equals just in the event that it can set up a distinction that it can protect, with the Elevate system Altius would meet those desires, such as conveying more prominent incentive to its clients with its fundamental item Victor TX, the leader premium line would in any case be offered in two renditions, one that amplified separation and one that underlined ââ¬Å"feelâ⬠around the greens with a recommended retail cost of $48 per dozen; or making practically identical incentive at a lower cost with Victor, the mid-run line, that would come in two forms, boosting either separation or control, and had a proposed retail cost of $39 per dozen or presenting another item, Elevate, the new worth line would come in four variants: for quick, medium, and moderate swing speeds, just as a non-adjusting offering. These would have a proposed cost of $27 per dozen. So ought to Altius make a move and present Elevate? As I would like to think I would state truly, the world is continually changing and on the off chance that you wear? t change with it you would stall out, despite the fact that on the off chance that you are the market chief, advancement implies building an upper hand over Altius contenders, that would mean changing its fundamental weaks into qualities, its dangers into circumstances. With Elevate, Altius would convey its primary items to its dedicated clients, which will continue purchasing the Victor TX as they are not value delicate; to the moderate golf players and tenderfoots, which would purchase Victor and Elevate, both are moderate or rare golf players, so they wont be eager to go through a great deal of cash in golf balls, and rather they could purchase Victor and Elevate. Altius golf, utilizing its perceived image name would build deals, in light of the fact that the reliable clients will continue getting them and the other two gatherings of clients would purchase its golf balls since its costs are a lot of lower and Altius is the best producer of golf balls, so that would draw in them despite the fact that they are eager to attempt new brands, Altius Golf is the market chief.
Pat Buchanans Candidacy free essay sample
Inspects firm stance moderate presidential competitors remains on financial matters, protectionism, migration, work, social issues and the effect on Republican Party. Pat Buchanan is a firm stance social traditionalist contender for the U.S. administration. Buchanans crusade stresses a no-bargain position on dubious issues, for example, fetus removal, unlawful movement, and protectionist exchange obstructions. In spite of the fact that kindred Republican up-and-comer Bob Dole hosts secured the get-together designation for president, Buchanan set a decent third behind the all around financed crusade of Steve Forbes. The versatility of help for Buchanans talk has raised worry among high-positioning Republicans, especially considering the moving toward GOP Convention in San Diego, where Buchanan could apply a basic effect on the partys battle stage. Monetary patriotism is the subject of Buchanans offer for the administration; his proverb is America first. Basically, Buchanan advocates coming back to the sorts of financial strategies that..
Friday, August 21, 2020
Compare two Member States participation and representation in the Research Paper
Look at two Member States support and portrayal in the European Parliament. Inquiries to answer are on Details segment - Research Paper Example My nations of decision are Czech Republic and Belgium. The decision for examination of the two European part states is a direct result of their difference in passage period. Belgium is one of the establishing countries having been available during the arrangement in 1952, while Czech came a lot later in 2004. Czech Republic is a youthful country shaped in 1993 after the split of Czechoslovakia. Belgium got autonomous in 1830. The hour of freedom is very extraordinary for the two countries and could have additionally affected the social-political and conservative advancement for every country. The political structure for the two countries additionally differs. Belgium is a government state and its political framework depends on parliamentary majority rules system under a protected government as the head of state. The administration is additionally isolated into the territorial government and network government. The lords hold the official forces, while the executive is the head of government and bureau. The leader is named by the ruler. The government parliament has two chambers: the House of Representatives and the senate (The Belgian House of Representatives and Senate, 2004). Czech Republic then again is a parliamentary majority rules system with independent administrative, official and legal forces. The parliament comprises of the office of representatives and the senate. In contrast to Belgium, the administration is a presidential framework whereby the president is chosen on a multi year term. It additionally has a PM delegated by the president (Prokop, 2010). The European parliament involves 24 agents who are chosen from Belgium. Corresponding portrayal is applied in the discretionary framework. In this political decision (European parliament), Belgium contains three constituent regions. The framework utilized is alluded to as dââ¬â¢Hondt equation and there is no restriction for the portrayal. After the political decision, individuals are as yet allowed to overrule the gathering administering competitors (European Election Database, n.d.).
Human Resource Management Benefits' Choices Research Paper
Human Resource Management Benefits' Choices - Research Paper Example Inability to genuinely react to these legitimately required advantages may bring about a business neglecting to hold the best of its representatives along these lines losing the extremely significant pull in and-hold game (Beam et al. P. 12). Bosses should anyway be keeping watch for the additional cost impacts identified with the arrangement of the above legitimately expected advantages to representatives. For expanded optional advantages, businesses should consistently be watching out not to lose their best workers. It is in this way basic that the most alluring representatives are recognized and held. To make progress at holding the best specialists, businesses need to search for the attributes that make workers generally attractive among their companions. The most alluring among todayââ¬â¢s representatives are those not exactly like the others, have great comical inclination, and are all the more captivating and active contrasted with others. Likewise, the most alluring representatives are not that worried about conventions, in this way pose their bosses more straightforward inquiries, particularly with respect to the following stage in task execution (MB Financial Bank, P. 7). The best representatives are likewise self-starters, don't get some much needed rest for unimportant reasons, and are once in a while, if at any time, behind schedule for work. Abnormally, the best represe ntatives are not compulsive workers but rather possibly remain after if there is extra real work to be done, never griping all the while (MB Financial Bank, P. 8). The best specialists are likewise task situated, use Job portrayal just as rule, and may require infrequent restriction while at work. At last, such workers don't anticipate applaud yet value it. MB Financial Bank. Advantage Packages for Employee: Employee Legally Required Benefits, 2012. Banking Resource Center. Recovered on May 29, 2012 from
Sunday, June 28, 2020
Importance of Technology in Medicine Essay - 275 Words
Importance of Technology in Medicine (Essay Sample) Content: IMPORTANCE OF TECHNOLOGY IN MEDICINENameProfessorCourseDateThe field of medicine has advanced exponentially with the introduction of technology. The benefits of technological advent in the medical field are evident. It has provided informative insights into new and existing viruses, bacteria, pathogens and the general physiology of the human body. Medical technology helps people all over the world and makes a diagnosis, treatment and monitoring of ailments relatively easier. Modern medicine is inseparable from technology. Technology helps improve health care quality and reduce medical costs.Technology has enabled much-needed efficiency in early detection of diseases or anomalies in the human body. Early detection of diseases and anomalies helps in preventing the development of diseases and gives insight on potentially dangerous conditions in the body. It can mark the difference between survival and death. Cancer, for instance, is manageable if detected in its early st ages. X-Rays and computerized tomography scans visualize and study parts of the body to reveal necessary information on their physiology and normalcy without exploratory surgery (Karen, 2012). These may help identify areas of concern before they become irreversible. Regular medical checkups may also help prevent several diseases and health conditions.Technology is also essential in improving the quality of health care. Various devices, like an electrocardiogram, are useful in monitoring vital signs and symptoms of a patient and relaying critical real-time data for doctorsà ¢Ã¢â ¬ use. This technological control enables better understanding of different conditions and facilitates accurate administration of corrective treatments and medication. New machines and electrical instruments are also vital in recording patientsà ¢Ã¢â ¬ data thus making it easier to access important reference information about a particular patient. Doctors can record administered medications or diagnosed conditions for future reference on electronics like computers.Assistive technologies are a great stride in the medical field. They enhance, support or even...
Tuesday, June 2, 2020
Transistor in General - Free Essay Example
Transistor A transistor is a semiconductor device used to amplify and switch electronic signals. It is made of a solid piece of semiconductor material, with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistors terminals changes the current flowing through another pair of terminals. Because the controlled (output) power can be much more than the controlling (input) power, the transistor provides amplification of a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits. The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Following its release in the early 1950s the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, amongst other things. Advantages The key advantages that have allowed transistors to replace their vacuum tube predecessors in most applications are * Small size and minimal weight, allowing the development of miniaturized electronic devices. Highly automated manufacturing processes, resulting in low per-unit cost. * Lower possible operating voltages, making transistors suitable for small, battery-powered applications. * No warm-up period for cathode heaters required after power application. * Lower power dissipation and generally greater energy efficiency. * Higher reliability and greater physical ruggedness. * Extremely long life. Some transistorized devices have been in service for mo re than 50 years. * Complementary devices available, facilitating the design of complementary-symmetry circuits, something not possible with vacuum tubes. Insensitivity to mechanical shock and vibration, thus avoiding the problem of microphonics in audio applications. Limitations * Silicon transistors do not operate at voltages higher than about 1,000 volts (SiC devices can be operated as high as 3,000 volts). In contrast, electron tubes have been developed that can be operated at tens of thousands of volts. * High power, high frequency operation, such as that used in over-the-air television broadcasting, is better achieved in electron tubes due to improved electron mobility in a vacuum. Silicon transistors are much more vulnerable than electron tubes to an electromagnetic pulse generated by a high-altitude nuclear explosion. Classification Transistors are categorized by * Semiconductor material: germanium, silicon, gallium arsenide, silicon carbide, etc. * Structure: BJT, JFET, IGF ET (MOSFET), IGBT, other types * Polarity: NPN, PNP (BJTs); N-channel, P-channel (FETs) * Maximum power rating: low, medium, high * Maximum operating frequency: low, medium, high, radio frequency (RF), microwave (The maximum effective frequency of a transistor is denoted by the term fT, an abbreviation for frequency of transition. The frequency of transition is the frequency at which the transistor yields unity gain). * Application: switch, general purpose, audio, high voltage, super-beta, matched pair * Physical packaging: through hole metal, through hole plastic, surface mount, ball grid array, power modules * Amplification factor hfe (transistor beta) Thus, a particular transistor may be described as silicon, surface mount, BJT, NPN, low power, high frequency switch. Bipolar junction transistor Bipolar transistors are so named because they conduct by using both majority and minority carriers. The bipolar junction transistor (BJT) is a combination of two junction diodes, and is formed of either a thin layer of p-type semiconductor sandwiched between two n-type semiconductors (an n-p-n transistor), or a thin layer of n-type semiconductor sandwiched between two p-type semiconductors (a p-n-p transistor). This construction produces two p-n junctions: a baseââ¬âemitter junction and a baseââ¬âcollector junction, separated by a thin region of semiconductor known as the base region (two junction diodes wired together without sharing an intervening semiconducting region will not make a transistor). The BJT has three terminals, corresponding to the three layers of semiconductor an emitter, a base, and a collector. It is useful in amplifiers because the currents at the emitter and collector are controllable by a relatively small base current. In an NPN transistor operating in the active region, the emitter-base junction is forward biased (electrons and holes recombine at the junction), and electrons are injected into the base region. Because the base is narrow, most of these electrons will diffuse into the reverse-biased (electrons and holes are formed at, and move away from the junction) base-collector junction and be swept into the collector; perhaps one-hundredth of the electrons will recombine in the base, which is the dominant mechanism in the base current. By controlling the number of electrons that can leave the base, the number of electrons entering the collector can be controlled. Collector current is approximately ? common-emitter current gain) times the base current. It is typically greater than 100 for small-signal transistors but can be smaller in transistors designed for high-power applications. The BJT is a lowââ¬âinput-impedance device. Also, as the baseââ¬âemitter voltage (Vbe) is increased the baseââ¬âemitter current and hence the collectorââ¬âemitter current (Ice) increase exponentially according to the Shockley diode model and the Ebers-Moll model. Because of this exponential r elationship, the BJT has a good transconductance. Simple circuit to show the labels of a BJT As an electronic switch Amplifier circuit Bipolar transistors can be made to conduct by exposure to light, since absorption of photons in the base region generates a photocurrent that acts as a base current; the collector current is approximately ? times the photocurrent. Devices designed for this purpose have a transparent window in the package and are called phototransistors. Field-effect transistor The field-effect transistor (FET), sometimes called a unipolar transistor, uses either electrons (in N-channel FET) or holes (in P-channel FET) for conduction. The four terminals of the FET are named source, gate, drain, and body (substrate). On most FETs, the body is connected to the source inside the package, and this will be assumed for the following description. In FETs, the drain-to-source current flows via a conducting channel that connects the source region to the drain region. The conductivity is varied by the electric field that is produced when a voltage is applied between the gate and source terminals; hence the current flowing between the drain and source is controlled by the voltage applied between the gate and source. As the gateââ¬âsource voltage (Vgs) is increased, the drainââ¬âsource current (Ids) increases exponentially for Vgs below threshold, and then at a roughly quadratic rate () (where VT is the threshold voltage at which drain current begins) in the space-charge-limited region above threshold. A quadratic behavior is not observed in modern devices, for example, at the 65 nm technology node. For low noise at narrow bandwidth the higher input resistance of the FET is advantageous. FETs are divided into two families: junction FET (JFET) and insulated gate FET (IGFET). The IGFET is more commonly known as a metalââ¬âoxideââ¬âsemiconductor FET (MOSFET), reflecting its original construction from layers of metal (the gate), oxide (the insulation), and semiconductor. Unlike IGFETs, the JFET gate forms a PN diode with the channel which lies between the source and drain. Functionally, this makes the N-channel JFET the solid state equivalent of the vacuum tube triode which, similarly, forms a diode between its grid and cathode. Also, both devices operate in the depletion mode, they both have a high input impedance, and they both conduct current under the control of an input voltage. Metalââ¬âsemiconductor FETs (MESFETs) are JFETs in which the reverse biased PN junction is replaced by a metalââ¬âsemiconductor Schottky-junction. These, and the HEMTs (high electron mobility transistors, or HFETs), in which a two-dimensional electron gas with very high carrier mobility is used for charge transport, are especially suitable for use at very high frequencies (microwave frequencies; several GHz). Unlike bipolar transistors, FETs do not inherently amplify a photocurrent. Nevertheless, there are ways to use them, especially JFETs, as light-sensitive devices, by exploiting the photocurrents in channelââ¬âgate or channelââ¬âbody junctions. FETs are further divided into depletion-mode and enhancement-mode types, depending on whether the channel is turned on or off with zero gate-to-source voltage. For enhancement mode, the channel is off at zero bias, and a gate potential can enhance the conduction. For depletion mode, the channel is on at zero bias, and a gate potential (of the opposite polarity) can deplete the channel, reducing conduction. For either mode, a more positive gate voltage corresponds to a higher current for N-channel devices and a lower current for P-channel devices. Nearly all JFETs are depletion-mode as the diode junctions would forward bias and conduct if they were enhancement mode devices; most IGFETs are enhancement-mode types. Single-electron transistors Single Electron Transistor (SET) consists of a gate island between two tunnelling junctions. The tunnelling current is controlled by a voltage applied to the gate through a capacitor. In physics, a Coulomb blockade (abbreviated QB), named after Charles-Augustin de Coulombs electrical force, is the increased resistance at small bias voltages of an electronic device comprising at least one low-capacitance tunnel junction. Because of the QB, the resistances of devices are not constant at low bias voltages, but increase to infinity for zero bias (i. e. no current flows). Single electron transistor Schematic of a single electron transistor Energy levels of source, island and drain (from left to right) in a single electron transistor for both the blocking state (upper part) and the transmitting state (lower part). Single electron transistor with niobium leads and aluminium island The simplest device in which the effect of Coulomb blockade can be observed is the so-called single electron transistor. It consists of two tunnel junctions sharing one common electrode with a low self-capacitance, known as the island. The electrical potential of the island can be tuned by a third electrode (the gate), capacitively coupled to the island. In the blocking state no accessible energy levels are within tunneling range of the electron (red) on the source contact. All energy levels on the island electrode with lower energies are occupied. When a positive voltage is applied to the gate electrode the energy levels of the island electrode are lowered. The electron (green 1. ) can tunnel onto the island (2. ), occupying a previously vacant energy level. From there it can tunnel onto the drain electrode (3. ) where it inelastically scatters and reaches the drain electrode Fermi level (4. ). The energy levels of the island electrode are evenly spaced with a separation of ? E. ?E is the energy needed to each subsequent electron to the island, which acts as a self-capacitance C. The lower C the bigger ? E gets. To achieve the Coulomb blockade, three criteria have to be met: * the bias voltage cant exceed the charging energy divided by the capacitance Vbias = à ; * the thermal energy kBT must be below the charging energy EC = , or else the electron will be able to pass the QB via thermal excitation; and * the tunneling resistance (Rt) should be greater than , which is derived from Heisenbergs Uncertainty principle. Coulomb Blockade Thermometer A typical Coulomb Blockade Thermometer (CBT) is made from an array of metallic islands, connected to each other through a thin insulating layer. A tunnel junction forms between the islands, and as voltage is applied, electrons may tunnel across this junction. The tunneling rates and hence the conductance vary according to the charging energy of the islands as well as the thermal energy of the system. Coulomb Blockade Thermometer is a primary thermometer based on electric conductance characteristics of tunnel junction arrays. The parameter V? =5. 439NkBT/e, the full width at half minimum of the measured differential conductance dip over an array of N junctions together with the physical constants provide the absolute temperature.
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