Why Technical English

Biofuels T o d a y

March 16, 2012
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In today world biofuels steadily attract public attention. Continuing the topic discussed in Biofuels Reduce Emissions (part 1), Biofuels Reduce Emissions (part 2), B i o f u e l s – do they interest you? we present the further technical text on the same theme. The author of the following post Is bioethanol economic fuel? Ing. Jiří Souček, CSc., who participated on biofuel research in the Czech Republic, is responding to the situation with bioethanol in Ukraine, briefly described in the text immediately below the post.

Is bioethanol economic fuel?

By Jiří Souček

Bioethanol is definitely economic fuel in the countries, where it is produced from sugarcane  at price about 4 CZK/L. In the USA bioethanol is mainly made from corn and maize and its production is supported by the State. In the Czech Republic there are 3 large factories producing bioethanol. By the Czech legislation bioethanol is used as a complement to petrol in amount up to 4.2 %. 

In a continuous process, this USI bioethanol p...

Je bioetanol ekonomické palivo?

Jiří Souček

Bioetanol je jednoznačně ekonomické palivo v zemích, kde se vyrábí z cukrové třtiny v ceně asi 4 Kč/l.  V USA je výroba bioetanolu podporována státem a vyrábí se hlavně z obilí a kukuřice. V ČR jsou 3 velké závody na výrobu bioetanolu, který se používá jako přídavek do benzinu v množství 4,2 %, což je stanoveno zákonem.

English: Bio Ethanol on the Way A plant for ma...

Production and usage of biofuels (bioethanol, biodiesel, etc.) is proper:

  1. in the countries with agrarian overproduction;
  2. in the countries where usage of biofuels is compulsory or is subsidised through e.g. reduced or zero VAT.
Biopaliva (bioetanol, biodiesel aj.) je vhodné vyrábět a používat:  

  1. v zemích, kde je nadvýroba zemědělských produktů;
  2. v zemích, kde je povinnost použití biopaliv stanovená zákonem, nebo použití biopaliv dotováno například sníženou nebo nulovou DPH.
The application of biofuels is motivated:  

  1. By effort to reduce greenhouse gases;
  2. By farmland utilization and intensification of employment  in agriculture (development of countryside);
  3. By intention to depress all components of exhaust emissions including particulates and cancerogenic substances;
  4. By endevoir to diminish dependence on fossil fuels import (petroleum, natural gas).

 

Použití biopaliv je motivováno:Deutsch: Variante des Ford Focus Turnier mit B...

  1. Snahou o snížení emisí skleníkových plynů;
  2. Využitím zemědělské půdy a zlepšením zaměstnanosti v zemědělství (rozvoj venkova);
  3. Potřebou snížit exhalace všech složek výfukových plynů včetně kancerogenních látek;
  4. Snažením zmenšit závislost na dovozu fosilních surovin (ropa, zemní plyn).
Technical problems of bioethanol application as   a motor fuel, examined  in the mentioned Ukrainian article, have altogether been solved    as the fuels are widely used in EU countries, the USA, Brazil, etc. for about 20 years. Technické problémy použití bioetanolu jako motorového paliva, uvedené ve zmíněném ukrajinském článku, jsou v podstatě vyřešeny. Bioetanol totiž je ve velkém množství již 20 let používán v zemích EU, USA, Brazílii aj.
In my opinion the biofuels are just a transitional stage in the alternative motor propellants development and the future will belong to electrical motors and biomass as a row material in chemical and other branches of industry. Předpokládám, že biopaliva jsou přechodnou etapou ve vývoji pohonných hmot.  Budoucnost vidím v elektromotorech a využití biomasy jako suroviny v chemickém a jiném průmyslu.
By my calculations expenses on biodiesel production are 1.4 up to 1.8 times higher than those on motor oil. Biodiesel will be an item of competitiveness under present prices if the fuel oil production price increases more than 22 CZK/L (0.9 EUR/L), i.e. a retail price makes about 43 CZK/L (1.7 EUR/L). It corresponds to the petroleum price  about 150 USD/ mil. L.  Dle mých propočtů jsou náklady na biodiesel  přibližně 1,4 až 1,8 vyšší než na motorovou naftu. Biodiesel bude v ČR podle současných cenových relací konkurenceschopný, jestliže výrobní cena nafty vzroste na více než 22 Kč/l (0,9 EUR/l), tj. prodejní maloobchodní cena bude kolem 43 Kč/l (1,7 EUR/l). To odpovídá ceně ropy asi 150 USD/mil. l.

A brief outline of bioethanol perspectives  in Ukraine

Drown up by Galina Vítková using Биоэтанол. Гладко было на бумаге, да забыли про овраги by Andrey Stadnik, BFM Group Ukraine

Stručný přehled situace s bioetanolem na Ukrajině

Vypracovala Galina Vítková podle Andreye Stadnika, BFM Group Ukraine: Биоэтанол. Гладко было на бумаге, да забыли про овраги 

At present biofuels, primarily bioethanol are widely discussed in Ukraine. The public as well as state bodies demonstrate their interest in supporting bioethanol production in spite of arising  obstacles. The Ukrainian Ministry of economy development and trade is preparing the State programme      of stimulating production and application of alternative fuels. Since   January 2012 a range of laws on the same topic  is being developed. Everything is done assuming that bioethanol producers and users should have   some advantages as those in the USA, Brazil and EU countries. V současné době probíhá na Ukrajině hodně diskuzí o biopalivech, především o bioetanolu. Veřejnost a státní orgány projevují zájem výrobu bioetanolu podpořit i přes vyskytující se komplikace. Ministerstvo ekonomického rozvoje a obchodu Ukrajiny připravuje „Státní program stimulování výroby a použití alternativních druhů paliva“. Od ledna 2012 se připravuje řada zákonů na stejné téma. Vychází se z toho, že výrobce a spotřebitelé bioetanolu mají mít určitá zvýhodnění, jak je tomu v USA, Brazílii a zemích EU.
The Ukrainian biofuel market is at its beginnings. Ethyl alcohol or ethanol is produced in a small amount by two factories. Since the complement  of ethyl alcohol to petrol makes up to 10%, this composite fuel has the same VAT as ordinary petrol. Ukrajinský trh s biopalivem je v počátečním stádiu. Etanol vyrábí v malém množství jen dvě továrny. Vzhledem k tomu, že přídavek etanolu do benzinu tvoří až 10%, toto směsné palivo má stejné DPH jako obyčejný benzin.
There are also technical obstacles for massive usage of biofuels, the most important of which are as:

  1. Increase of electric conduction of petrol with bioethanol, which causes larger corrosion of a motor petrol tank, exhaust manifold, seals and other car components.
  2. Another technical problem concerns far higher temperature of bioethanol evaporation, which leads to troubles with firing and running  a motor while cold outdoor.
  3. But the most serious problem is increasing hygroscopicity of petrol with bioethanol, which causes great difficulties with the mixed fuel storing and transporting.       
Existují i technické překážky  pro masové použití biopaliva, z nichž nejdůležitější jsou tyto:

  1. Zvýšení elektrické vodivosti benzinu s bioetanolem, což vede k větší korozi nádrže auta, potrubí, těsnění a ostatního materiálu.
  2.  Dalším technickým problémem je značně vyšší teplota odpařování bioetanolu, což má za následek obtíže při zapalování motoru a rozjezdu auta  za nízkých teplot.
  3. Ale nejzávažnějším problémem je zvýšení hygroskopických vlastností benzinu s bioetanolem, které způsobuje velké nesnáze při  skladování a dopravě tohoto směsného paliva
From the economical viewpoint bioethanol production is characterised in such a way:

  1. Building a factory with productivity less than 60 kilotons (75 mil. L) is economically profitless.   
  2. Bioethanol production depletes the great amount of electricity.       
  3. Serious problems with sale of side products   of  bioethanol manufacture such as Dried Distillers Grains with Solubles (DDGS), carbonic acid gas, etc. also arise.
  4. Another great issue is row materials storing. Bioethanol in Ukraine is produced from corn and maize. The best solution is to buy them in necessary amount closely after picking harvest. For doing it large storage capacities need to be built.  
Podíváme-li se na ekonomickou stránku výroby bioetanolu, zjistíme, že:

  1. Výstavba továrny o výkonu menším než 60 tisíc t (75 mil.l) je ekonomicky nevýhodná.
  2. Výroba bioetanolu vyžaduje velkou spotřebu elektrické energie.
  3. Navíc vznikají problémy s odbytem vedlejších produktů výroby bioetanolu, například, výpalků (DDGS), oxidu uhličitého aj.
  4.  Dalším velkým problémem je skladování surovin. Bioetanol se na Ukrajině vyrábí z kukuřice a obilí. Tyto je nejlépe kupovat v potřebném množství ihned po sklizni úrody. To vyžaduje vybudování velkých skladovacích prostor. 

    Sustainable Feedstocks for Biofuels, Chemicals

Establishment of a vertically integrated holding, which would include all producing procedures  from plants growing up to sale, could be the best solution for these problems. At a rough estimate total expenses on such a holding erection may amount to a milliard EUR.

In author´s opinion such projects cannot be realised in Ukraine at present.  

Optimálním řešením může být vytvoření vertikálně integrovaného holdingu, jehož součástí jsou všechny výrobní procesy pěstováním  rostlin počínaje a odbytem konče. Celkové náklady na vybudování tohoto holdingu mohou odhadem činit až miliardu EUR.  

Podle autora se takovéto projekty nemohou  v současné době na Ukrajině realizovat. 

PS: The whole text of the article Биоэтанол. Гладко было на бумаге, да забыли про овраги is brought at http://www.bfm-ua.com.   PS: Plné znění článku Биоэтанол. Гладко было на бумаге, да забыли про овраги je uvedeno na http://www.bfm-ua.com.

What about you? What is your own opinion on bioethanol?

Write down a comment rather in English , but you may write it in Czech, too.

 A co Vy? Máte svůj vlastni  názor na bioetanol?

 Napište komentář, nejlépe anglicky, ale můžete napsat i česky.

NOTE

  • Kč  =  Czech crown (CZK)
  • DPH  =  VAT (value-added tax)
  • ČR  =  the Czech Republic

 

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Website – basic information

November 28, 2011
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Website and Its Characteristics

                                                                                             Composed by Galina Vitkova using Wikipedia

A website (or web site) is a collection of web pages, typically common to a particular domain name on the Internet. A web page is a document usually written in HTML (Hyper Text Markup Language), which is almost always accessible via HTTP (Hyper-Text Transport Protocol). HTTP is a protocol that transfers information from the website server to display it in the user’s web browser. All publicly accessible web sites constitute the immense World Wide Web of information. More formally a web site might be considered a collection of pages dedicated to a similar or identical subject or purpose and hosted through a single domain.

The pages of a website are approached from a common root URL (Uniform Resource Locator or Universal Resource Locator) called the homepage, and usually reside on the same physical server. The URLs of the pages organise them into a hierarchy. Nonetheless, the hyperlinks between web pages regulate how the reader perceives the overall structure and how the traffic flows between the different parts of the sites. The first on-line website appeared in 1991 in CERN (European Organization for Nuclear Research situated in the suburbs of Geneva on the Franco–Swiss border) – for more information see ViCTE Newsletter Number 5 – WWW History (Part1) / May 2009, Number 6 – WWW History (Part2) / June 2009.

A website may belong to an individual, a business or other organization. Any website can contain hyperlinks to any other web site, so the differentiation one particular site from another may sometimes be difficult for the user.

Websites are commonly written in, or dynamically converted to, HTML and are accessed using a web browser. Websites can be approached from a number of computer based and Internet enabled devices, including desktop computers, laptops, PDAs (personal digital assistant or personal data assistant) and cell phones.

Website Drafts and Notes

Image by Jayel Aheram via Flickr

A website is hosted on a computer system called a web server or an HTTP server. These terms also refer to the software that runs on the servers and that retrieves and delivers the web pages in response to users´ requests.

Static and dynamic websites are distinguished. A static website is one that has content which is not expected to change frequently and is manually maintained by a person or persons via editor software. It provides the same available standard information to all visitors for a certain period of time between updating of the site.

A dynamic website is one that has frequently changing information or interacts with the user from various situation (HTTP cookies or database variables e.g., previous history, session variables, server side variables, etc.) or direct interaction (form elements, mouseovers, etc.). When the web server receives a request for a given page, the page is automatically retrieved from storage by the software. A site can display the current state of a dialogue between users, can monitor a changing situation, or provide information adapted in some way for the particular user.

Static content may also be dynamically generated either periodically or if certain conditions for regeneration occur in order to avoid the performance loss of initiating the dynamic engine

Website Designer & SEO Company Lexington Devel...
Image by temptrhonda via Flickr

Some websites demand a subscription to access some or all of their content. Examples of subscription websites include numerous business sites, parts of news websites, academic journal websites, gaming websites, social networking sites, websites affording real-time stock market data, websites providing various services (e.g., websites offering storing and/or sharing of images, files, etc.) and many others.

For showing active content of sites or even creating rich internet applications plagins such as Microsoft Silverlight, Adobe Flash, Adobe Shockwave or applets are used. They provide interactivity for the user and real-time updating within web pages (i.e. pages don’t have to be loaded or reloaded to effect any changes), mainly applying the DOM (Document Object Model) and JavaScript.

There are many varieties of websites, each specialising in a particular type of content or use, and they may be arbitrarily classified in any number of ways. A few such classifications might include: Affiliate, Archive site, Corporate website, Commerce site, Directory site and many many others (see a detailed classification in Types of websites).

In February 2009, an Internet monitoring company Netcraft, which has tracked web growth since 1995, reported that there were 106,875,138 websites in 2007 and 215,675,903 websites in 2009 with domain names and content on them, compared to just 18,000 Web sites in August 1995.

 PS:  Spellingwhat is the better, what is correct: “website OR “web site?

The form “website” has gradually become the standard spelling. It is used, for instance, by such leading dictionaries and encyclopedias as the Canadian Oxford Dictionary, the Oxford English Dictionary, Wikipedia. Nevertheless, a form “web site” is still widely used, e.g. Encyclopædia Britannica (including its Merriam-Webster subsidiary). Among major Internet technology companies, Microsoft uses “website” and occasionally “web site”, Apple uses “website”, and Google uses “website”, too.

 PSS: Unknown technical terms you can find in the Internet English Vocabulary.

 Reference      Website – Wikipedia, the free encyclopedia

Have You Donated To Wikipedia Already?

Do you use Wikipedia? Do you know that Jimmy Wales, a foundator of Wikipedia, decided to keep Wikipedia advertising free and unbiased. So, they have financial problems with surviving now. Any donation, even a small sum is helpful. Thus, here’s the page where you can donate.

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Right now within preparing the e-book “Internet English” (see ViCTE Newsletter Number 33 – WWW, Part 1 / August 2011 ) posts on this topic are being published there. Your comments to the posts are welcome.

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Intermittence of renewables

June 30, 2011
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Composed by Galina Vitkova

Everybody knows that renewables are expensive, sometimes very expensive and make electricity price go up. For example, in the Czech Republic the expansion of building solar photovoltaic installations, donated from the state budget, caused increasing electricity price over 12 %. Another example of increasing the costs is given in the table below.

Increase in system operation costs (Euros per MW·h) for 10% and 20% wind share[7]

 

Germany

Denmark

Finland

Norway

Sweden

10%

2.5

0.4

0.3

0.1

0.3

20%

3.2

0.8

1.5

0.3

0.7

Nevertheless, only few people are aware of great intermittence of renewables, which excludes their usage as a main source of electricity generation not only nowadays, but in the future too. Actually no technical and industrial society can exist and develop using unreliable and intermittent power supplies. Nothing in our integrated and automated world works without electricity, this life-blood of technical civilisation. Just imagine what would happen to a society where electricity supply is turned off only for a short time, possibly every week, or if the power is cut for a whole fortnight or more. Life stops, production ceases, chaos sets in. And this is exactly what could arise if we bank on renewables. Thus let us take notice of features specific for wind and solar (photovoltaic) power installations, which are typically built in Europe. 

A straight line projection from where we are t...

Image via Wikipedia

The entire problem with renewables is that they are perilously intermittent power sources. The electricity produced using them is not harmonized with the electrical demand cycle. Renewable based installations generate electricity when the wind blows or the sun shines. Since the energy produced earlier in the day cannot be stored extra generating capacity will have to be brought on-line to cover the deficiency. This means that for every renewable based system installed, a conventional power station will have to be either built or retained to ensure continuity of energy supply. But this power station will have to be up and running all the time (i.e. to be a ’spinning-reserve’) because it takes up to 12 hours to put a power station on-line from a cold start-up. Thusly if we want to keep up continuity of supply the renewable sources result in twice the cost and save very little of fossil fuels.

Wind power is extremely variable. Building thousands of wind turbines still does not resolve the fundamental problem of the enormous wind variability. When days without significant winds occur, it doesn’t matter how many wind turbines are installed as they all go off-line. So, it is extremely difficult to integrate wind power stations into a normal generating grid.  

Solar energy is not available at night and cloudy days, which makes energy storage the most important issue in providing the continuous availability of energy. Off-grid photovoltaic systems traditionally use rechargeable batteries to store excess electricity. With grid-tied systems excess electricity can be sent to the transmission grid and later be settled.

Renewable energy supporters declare that renewable power can somehow be stored to cope with power outages. The first of these energy storage facilities, which comes to aid the thousands of wind-turbines motionless when winds do not blow and solar installations without generating when the sun does not shine, is the pumped water storage system. However, this claim is not well-founded for the following reasons:

  • In most countries of Europe pumped storage systems are already fully used for overpowering variability in electrical demand, and so as a rule they have no extra capacity for overcoming variability in supply due to the unreliable wind and solar generation systems.
  • Pumped storage systems have limited capacity, which can be used for electricity generating  for just a few hours, while wind or solar generation systems can go off-line for days or weeks at a time.
  • Pumped storage systems are not only hugely expensive to construct, the topography of european countries ensure that very few sites are available.

As for flywheel energy storage, compressed air storage, battery storage and hydrogen storage each of these systems is highly complicated, very expensive, hugely inefficient and limited in capacity. The hydrogen storage is especially popular and hyped among proponents of renewables. The hydrogen, produced and stored when renewables generate more electricity than it could be used, is supposed to propel vehicles and generators. Unfortunately these hydrogen powered vehicles and generators are only about 5% efficient. In addition, hydrogen storage vessels are highly flammable and potentially explosive. Practically nowadays there is no energy system available that can remotely be expected to replace renewable energy resources in a large scale, while they are out of functioning.

In numerous publications about renewables we are chiefly informed about expanding and increasing investments in renewables, multiplying their installed capacity and volumes of produced electricity, everything in absolute values, without comparing these indicators with values of other resources, especially when they speak about volumes of production. In the table below you find comparable values of volumes electricity produced by nuclear power plants and renewable installations. Look it through and have your own opinion of the problem.

Comparison of nuclear and renewable electricity producing by top nuclear electricity producers (TW·h-year/% of total electricity production in the country)

 

Country

Year

Nuclear  2007

Wind Power

Solar Power

1 USA 2009

837/19.4%

70.8/1.64%

0.808/0.019%

2 Japan 2008

264/23.5%

1.754/0.156%

0.002/0.000%

3 Russia 2008

160/15.8%

0.007/0.0007%

 

4 Germany 2010

141/22.3%

36.5/5.499%

12.0/1.898%

5 Canada 2008

93/14.6%

2.5/0.392%

0.017/0.003%

Conclusion: Common people must know and must interest about situation in producing and supplying electricity. Only then they will be able to enforce on the governments to make rightdecisions in order to ensure stable supplying electricity, without which modern civilisation cannot exist and improve.

 References:


Study in Ireland

June 12, 2011
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Dear friends of Technical English,
Here below you find a description of how my former student sees his experience with studying in Ireland. Nowadays there are many opportunities for studying and teaching everywhere across Europe. Learn Technical English and you can get staying at some Europe´s technical university.  Galina Vitkova
 
All Ireland Flag

All Ireland Flag

My study in Ireland

By David Jirovec

I spent 8.5 months (both winter and summer semesters) in Ireland within the EU programme Erasmus. In Cork, Ireland‘s second biggest city, I was studying computer science, the same subject as at the Czech Technical University (CTU) in Prague About studying in Ireland, namely at the Cork Institute of Technology(CIT), it is rather similar to studying at a high school in Bohemia. A student attends his/her class of about 20 participants and these people study nearly all courses together. We were recommended to choose one of these classes and join it. But since I am in my final year at CTU, I couldn’t find any class with suitable combination of courses. So finally, I took each course with a different class. 

Cork City Marathon 2011

Cork City Marathon 2011

These small classes are set for both lectures and labs, so there are no extended lectures for 200 participants as at CTU. Students are never asked to go to and show something at the blackboard to whole class, results of any student’s tests are never shown to other students.

Exams are carried out only in a written form. They take place in very big halls, where students from different courses are present at the same time. Very strict security measures are held there, students cannot take any bags with themselves, it is forbidden to have even a mobile phone there. Exams are easier than at CTU, sometimes it is like choosing 3 questions out of total 5 and answering them, instead of solving all questions. Worse is that there are no 3 free exam attempts as at CTU. If a student fails once, it is possible to try again in the summer, but it costs some euros. There is no a given minimum of points for any test, it is only  necessary to have a sum of at least 40/100 points at the end of a semester for both in semester work and exams. And no compulsory attendance at any classes is required.

Seat of the Rectorate of the Czech Technical U...

Seat of the Rectorate of CTU in Prague

 
Relationships between students and teachers are very good, teachers are friendly and helpful. I had no problems with my English in classes, teachers were easy to understand, but sometimes it was more difficult to understand the students, especially when they were talking to each other. I don’t see much improvement in my English grammar, but my communication skills in English improved much. It was definitely very profitable to use English for all day-to-day tasks and conversation, and observe the little differences between English commonly used in Ireland and English language taught at school in Prague. Irish people speak English, which mostly is just a slang language. So, I recommend anybody who is going to visit Ireland to apply http://www.urbandictionary.com/define.php?term=what%27s+the+craic%3F in order to understand phrases brought about by Celtic community dialects.

PS The ERASMUS Programme – studying in Europe and more – is the EU’s flagship education and training programme enabling 200 000 students to study and work abroad each year. In addition, it funds co-operation between higher education institutions across Europe. The programme not only supports students, but also professors and business staff who want to teach abroad, as well as helping university staff to receive training. European Commission , Education & Training (http://ec.europa.eu/education/lifelong-learning-programme/doc80_en.htm)


Fuel cycle in fusion reactors

May 25, 2011
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Composed by Galina Vitkova

Common notes

The basic concept behind any fusion reaction is to bring two or more nuclei close enough together, so that the nuclear force in nuclei will pull them together into one larger nucleus. If two light nuclei fuse, they will generally form a single nucleus with a slightly smaller mass than the sum of their original masses (though this is not always the case). The difference in mass is released as energy according to Albert Einstein’s mass-energy equivalence formula E = mc2. If the input nuclei are sufficiently massive, the resulting fusion product will be heavier than the sum of the reactants’ original masses. Due to it the reaction requires an external source of energy. The dividing line between “light” and “heavy” nuclei is iron-56. Above this atomic mass, energy will generally be released by nuclear fission reactions; below it, by fusion.

Fusion between the nuclei is opposed by their shared electrical charge, specifically the net positive charge of the protons in the nucleus. In response to it some external sources of energy must be supplied to overcome this electrostatic force. The easiest way to achieve this is to heat the atoms, which has the side effect of stripping the electrons from the atoms and leaving them as nuclei. In most experiments the nuclei and electrons are left in a fluid known as a plasma. The temperatures required to provide the nuclei with enough energy to overcome their repulsion is a function of the total charge. Thus hydrogen, which has the smallest nuclear charge, reacts at the lowest temperature. Helium has an extremely low mass per nucleon and therefore is energetically favoured as a fusion product. As a consequence, most fusion reactions combine isotopes of hydrogen (“protium“, deuterium, or tritium) to form isotopes of helium.

In both magnetic confinement and inertial confinement fusion reactor designs tritium is used as a fuel. The experimental fusion reactor ITER (see also The Project ITER – past and present) and the National Ignition Facility (NIF) will use deuterium-tritium fuel. The deuterium-tritium reaction is favorable since it has the largest fusion cross-section, which leads to the greater probability of a fusion reaction occurrence.

Deuterium-tritium (D-T) fuel cycle

D-T fusion

Deuterium-tritium (D-T) fusion

 

The easiest and most immediately promising nuclear reaction to be used for fusion power is deuterium-tritium Fuel cycle. Hydrogen-2 (Deuterium) is a naturally occurring isotope of hydrogen and as such is universally available. Hydrogen-3 (Tritium) is also an isotope of hydrogen, but it occurs naturally in only negligible amounts as a result of its radioactive half-life of 12.32 years. Consequently, the deuterium-tritium fuel cycle requires the breeding of tritium from lithium. Most reactor designs use the naturally occurring mix of lithium isotopes.

Several drawbacks are commonly attributed to the D-T fuel cycle of the fusion power:

  1. It produces substantial amounts of neutrons that result in induced radioactivity within the reactor structure.
  2. The use of D-T fusion power depends on lithium resources, which are less abundant than deuterium resources.
  3. It requires the handling of the radioisotope tritium. Similar to hydrogen, tritium is difficult to contain and may leak from reactors in certain quantity. Hence, some estimates suggest that this would represent a fairly large environmental release of radioactivity.

Problems with material design

The huge neutron flux expected in a commercial D-T fusion reactor poses problems for material design. Design of suitable materials is under way but their actual use in a reactor is not proposed until the generation later ITER (see also The Project ITER – past and present). After a single series of D-T tests at JET (Joint European Torus, the largest magnetic confinement experiment currently in operation), the vacuum vessel of the fusion reactor, which used this fuel, became sufficiently radioactive. So, remote handling needed to be used for the year following the tests.

In a production setting, the neutrons react with lithium in order to create more tritium. This deposits the energy of the neutrons in the lithium, for this reason it should be cooled to remove this energy. This reaction protects the outer portions of the reactor from the neutron flux. Newer designs, the advanced tokamak in particular, also use lithium inside the reactor core as a key element of the design.

PS: I strongly recommend to read the article FUSION(A Limitless Source Of Energy). It is a competent technical text for studying Technical English. Consequently it offers absorbing information about the topic.

 


Fusion reactors in the world

May 10, 2011
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Implosion of a fusion microcapsule on the NOVA...

Implosion of a fusion microcapsule

Composed by Galina Vitkova

Fusion power is power generated by nuclear fusion processes. In fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. During the process a comparatively large amount of energy is released.

The term “fusion power” is commonly used to refer to potential commercial production of usable power from a fusion source, comparable to the usage of the term “steam power”. Heat from the fusion reactions is utilized to operate a steam turbine which in turn drives electrical generators, similar to the process used in fossil fuel and nuclear fission power stations.

Fusion power has significant safety advantages in comparison with current power stations based on nuclear fission. Fusion only takes place under very limited and controlled conditions So, a failure of precise control or pause of fueling quickly shuts down fusion power reactions. There is no possibility of runaway heat build-up or large-scale release of radioactivity, little or no atmospheric pollution. Furthermore, the power source comprises light elements in small quantities, which are easily obtained and largely harmless to life, the waste products are short-lived in terms of radioactivity. Finally, there is little overlap with nuclear weapons technology.

 

Fusion Power Grid

Fusion Power Grid

 

Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections which were extended by several decades. More than 60 years after the first attempts, commercial fusion power production is still believed to be unlikely before 2040.

The leading designs for controlled fusion research use magnetic (tokamak design) or inertial (laser) confinement of a plasma.

Magnetic confinement of a plasma

The tokamak (see also Number 29 – Easy such and so / April 2011, Nuclear powertokamaks), using magnetic confinement of a plasma, dominates modern research. Very large projects like ITER (see also  The Project ITER – past and present) are expected to pass several important turning points toward commercial power production, including a burning plasma with long burn times, high power output, and online fueling. There are no guarantees that the project will be successful. Unfortunately, previous generations of tokamak machines have revealed new problems many times. But the entire field of high temperature plasmas is much better understood now than formerly. So, ITER is optimistically considered to meet its goals. If successful, ITER would be followed by a “commercial demonstrator” system. The system is supposed to be similar in purpose to the very earliest power-producing fission reactors built in the period before wide-scale commercial deployment of larger machines started in the 1960s and 1970s.

Ultrascale scientific computing, combined with...

Ultrascale scientific computing

 

Stellarators, which also use magnetic confinement of a plasma, are the earliest controlled fusion devices. The stellator was invented by Lyman Spitzer in 1950 and built the next year at what later became the Princeton Plasma Physics Laboratory. The name “stellarator” originates from the possibility of harnessing the power source of the sun, a stellar object.

Stellarators were popular in the 1950s and 60s, but the much better results from tokamak designs led to their falling from favor in the 1970s. More recently, in the 1990s, problems with the tokamak concept have led to renewed interest in the stellarator design, and a number of new devices have been built. Some important modern stellarator experiments are Wendelstein, in Germany, and the Large Helical Device, inJapan.

Inertial confinement fusion

Inertial confinement fusion (ICF) is a process where nuclear fusion reactions are initiated by heating and compressing a fuel target, typically in the form of a pellet. The pellets most often contain a mixture of deuterium and tritium.

Inertial confinement fusion

Inertial confinement fusion

 

To compress and heat the fuel, energy is delivered to the outer layer of the target using high-energy beams of laser light, electrons or ions, although for a variety of reasons, almost all ICF devices to date have used lasers. The aim of ICF is to produce a state known as “ignition”, where this heating process causes a chain reaction that burns a significant portion of the fuel. Typical fuel pellets are about the size of a pinhead and contain around 10 milligrams of fuel. In practice, only a small proportion of this fuel will undergo fusion, but if all this fuel were consumed it would release the energy equivalent to burning a barrel of oil.

To date most of the work in ICF has been carried out in Franceand the United States, and generally has seen less development effort than magnetic approaches. Two large projects are currently underway, the Laser Mégajoule in France and the National Ignition Facility in theUnited States.

All functioning fusion reactors are listed in eFusion experimental devices classified by a confinement method.

 Reference: Wikipedia, the free encyclopedia http://en.wikipedia


The Project ITER – past and present

April 30, 2011
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Composed by Galina Vitkova

 

The logo of the ITER Organization

The logo of the ITER Organization

 

„We firmly believe that to harness fusion energy is the only way to reconcile huge conflicting demands which will confront humanity sooner or later“

Director-General Osamu Motojima,  Opening address, Monaco International ITER Fusion Energy Days, 23 November 2010

 

ITER was originally an acronym for International Thermonuclear Experimental Reactor, but that title was dropped in view of the negatively popular connotation of “thermonuclear“, especially in conjunction with “experimental”. “Iter” also means “journey”, “direction” or “way” in Latin, taking into consideration ITER potential role in harnessing nuclear fusion (see also The ViCTE Newsletter Number 28 – SVOMT revising/March 2011 Nuclear power – fission and fusion) as a peaceful power source.

ITER is a large-scale scientific project intended to prove the practicability of fusion as an energy source, to prove that it can work without negative impact. Moreover, it is expected to collect the data necessary for the design and subsequent operation of the first electricity-producing fusion power plant. Besides, it aims to demonstrate the possibility to produce commercial energy from fusion. ITER is the culmination of decades of fusion research: more than 200 tokamaks (see also The ViCTE Newsletter Number 29 – Easy such and so / April 2011 Nuclear power – tokamaks) built over the world have paved the way to the ITER experiment. ITER is the result of the knowledge and experience these machines have accumulated. ITER, which will be twice the size of the largest tokamak currently operating, is conceived as the necessary experimental step on the way to a demonstration of a fusion power plant potential.

The scientific goal of the ITER project is to deliver ten times the power it consumes. From 50 MW of input power, the ITER machine is designed to produce 500 MW of fusion power – the first of all fusion experiments producing net energy. During its operational lifetime, ITER will test key technologies necessary for the next step, will develop technologies and processes needed for a fusion power plant – including superconducting magnets and remote handling (maintenance by robot). Furthermore, it will verify tritium breeding concepts, will refine neutron shield/heat conversion technology. As a result the ITER project will demonstrate that a fusion power plant is able to capture fusion energy for commercial use.

Launched as an idea for international collaboration in 1985, now the ITER Agreement includes China, the European Union, India, Japan, Korea, Russia and the United States, representing over half of the world’s population. Twenty years of the design work and complex negotiations have been necessary to bring the project to where it is today.

The ITER Agreement was officially signed at theElyséePalaceinParison21 November 2006by Ministers from the seven ITER Members. In a ceremony hosted by French President Jacques Chirac and the President of the European Commission M. José Manuel Durao Barroso, this Agreement established a legal international entity to be responsible for construction, operation, and decommissioning of ITER.

On24 October 2007, after ratification by all Members, the ITER Agreement entered into force and officially established the ITER Organization. ITER was originally expected to cost approximately €5billion. However, the rising price of raw materials and changes to the initial design have augmented that amount more than triple, i.e. to €16billion.

Cost Breakdown of ITER Reactor

Cost Breakdown of ITER Reactor

 

The program is anticipated to last for 30 years – 10 for construction, and 20 of operation. The reactor is expected to take 10 years to build with completion in 2018. The ITER site in Cadarache, France stands ready: in 2010, construction began on the ITER Tokamak and scientific buildings. The seven ITER Members have shared in the design of the installation, the creation of the international project structure, and in its funding.

Key components for the Tokamak will be manufactured in the seven Member States and shipped to Franceby sea. From the port in Berre l’Etang on the Mediterranean, the components will be transported by special convoy along the 104 kilometres of the ITER Itinerary to Cadarache. The exceptional size and weight of certain of the Tokamak components made large-scale public works necessary to widen roads, reinforce bridges and modify intersections. Costs were shared by the Bouches-du-Rhône department Council (79%) and theFrenchState (21%). Work on the Itinerary was completed in December, 2010.

Two trial convoys will be organized in 2011 to put the Itinerary’s resistance and design to the test before a full-scale practice convoy in 2012, and the arrival of the first components for ITER by sea.

Between 2012 and 2017, 200 exceptional convoys will travel by night at reduced speeds along the ITER Itinerary, bypassing 16 villages, negotiating 16 roundabouts, and crossing 35 bridges.

Manufacturing of components for ITER has already begun in Members industries all over the world. So, the level of coordination required for the successful fabrication of over one million parts for the ITER Tokamak alone is daily creating a new model of international scientific collaboration.

ITER, without question, is a very complex project. Building ITER will require a continuous and joint effort involving all partners. In any case, this project remains a challenging task and for most of participants it is a once-in-a-lifetime opportunity to contribute to such a fantastic endeavour.

 

References:


Nuclear energy future after Fukushima

March 23, 2011
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Composed by Galina Vitkova

What the damage to the Fukushima plant (see picture below) forecasts for Japan—and the world? But first, let us introduce general description of nuclear power stations in order to sense problems caused by the breakdown. 

 

The Fukushima 1 NPP

Image via Wikipedia

 Nuclear fission. Nowadays nuclear power stations generate energy using nuclear fission (Fukushima belongs to this type of nuclear power plants). Atoms of uranium (235) rods in the reactor are split in the process of fission and cause a chain reaction with other nuclei. During this process a large amount of energy is released. The energy heats water to create steam, which rotates a turbine together with a generator, producing electricity.

Depending on the type of fission, presumptions for ensuring supply of the fuel at existing level varies from several decades for the Uranium-235 to thousands of years for uranium-238. At the present rate of use, uranium-235 reserves (as of 2007) will be exhausted in about 70 years. The nuclear industry persuades that the cost of fuel makes a minor cost component for fission power. In future, mining of uranium sources could be more expensive, more difficult. However, increasing the price of uranium would have little brought about the overall cost of nuclear power. For instance, a doubling in the cost of natural uranium would increase the total cost of nuclear power by 5 percent. On the other hand, double increasing of natural gas price results in 60 percent growth of the cost of gas-fired power.

The possibility of nuclear meltdowns and other reactor accidents, such as the Three Mile Island accident and the Chernobyl disaster, have caused much public concern. Nevertheless, coal and hydro- power stations have both accompanied by more deaths per energy unit produced than nuclear power generation.

At present, nuclear energy is in decline, according to a 2007 World Nuclear Industry Status Report presented in the European Parliament. The report outlines that the share of nuclear energy in power production decreased in 21 out of 31 countries, with five fewer functioning nuclear reactors than five years ago. Currently 32 nuclear power plants are under construction or in the pipeline, 20 fewer than at the end of the 1990s.

Fusion. Fusion power could solve many of fission power problems. Nevertheless, despite research started in the 1950s, no commercial fusion reactor is expected before 2050. Many technical problems remain unsolved. Proposed fusion reactors commonly use deuterium and lithium as fuel.  Under assumption that a fusion energy output will be kept in the future, then the known lithium reserves would endure 3000 years, lithium from sea water would endure 60 million years. A more complicated fusion process using only deuterium from sea water would have fuel for 150 billion years.

Due to a joint effort of the European Union (EU), America, China, India, Japan, Russia and South Korea a prototype reactor is being constructed on a site in Cadarache (in France). It is supposed to be put into operation by 2018.

Initial projections in 2006 put its price at €10 billion ($13 billion): €5 billion to build and another €5 billion to run and decommission the thing. Since then construction costs alone have tripled.

As the host, the EU is committed to covering 45% of these, with the other partners contributing about 9% each. In May 2010 the European Commission asked member states to conduce an additional €1.4 billion to cope with the project over to 2013. Member states rejected the request.

Sustainability: The environmental movement emphasizes sustainability of energy use and development. “Sustainability” also refers to the ability of the environment to cope with waste products, especially air pollution.

The long-term radioactive waste storage problems of nuclear power have not been fully solved till now. Several countries use underground repositories. Needless to add nuclear waste takes up little space compared to wastes from the chemical industry which remains toxic indefinitely.

Future of nuclear industry. Let us return to how the damage to the Fukushima plant affects future usage of nuclear power in the future in Japan – and in the world.

Share of nuclear electricity production in total domestic production

Nowadays nuclear plants provide about a third of Japan’s electricity (see chart), Fukushima is not the first to be paralysed by an earthquake. But it is the first to be stricken by the technology dependence on a supply of water for cooling.

The 40-year-old reactors in Fukushima run by the Tokyo Electric Power Company faced a disaster beyond anything their designers were required to imagine.

What of the rest of the world? Nuclear industry supporters had hopes of a nuclear renaissance as countries try to reduce carbon emissions. A boom like that of the 1970s is talked, when 25 or so plants started construction each year in rich countries. Public opinion will surely take a dive. At the least, it will be difficult to find the political will or the money to modernise the West ageing reactors, though without modernisation they will not become safer. The heartless images from Fukushima, and the sense of lurching misfortune, will not be forgotten even if final figures unveil little damage to health. France, which has 58 nuclear reactors, seems to see the disaster in Japan as an opportunity rather than an obstacle for its nuclear industry. On March 14th President Nicolas Sarkozy said that French-built reactors have lost international tenders because they are expensive: “but they are more expensive because they are safer.”

However, the region where nuclear power should grow fastest, and seems to be deterred, is the rest of Asia. Two-thirds of the 62 plants under construction in the world are in Asia. Russia plans another ten. By far the most important arising nuclear power is China, which has 13 working reactors and 27 more on the way. China has announced a pause in nuclear commissioning, and a review. But its leaders know that they must go away from coal: the damage to health from a year of Chinese coal-burning plants is bigger then from nuclear industry. And if anyone can build cheap nuclear plants, it is probably the Chinese.

In case the West turns its back on nuclear power and China holds on, the results could be unfortunate. Nuclear plants need trustworthy and transparent regulation.

  References

  • The risks exposed: What the damage to the Fukushima plant portends for Japan—and the world; The Economist, March 19th 2011
  • Expensive Iteration: A huge international fusion-reactor project faces funding difficulties; The Economist, July 22nd 2010  

 

 


Game Theory in Computer Science

January 25, 2011
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        By Galina Vitkova  

Computer science or computing science (sometimes abbreviated CS) is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems. It concerns the systematic study of algorithmic processes that describe and transform information. Computer science has many sub-fields. For example, computer graphics, computational complexity theory (studies the properties of computational problems), programming language theory (studies approaches to describing computations), computer programming (applies specific programming languages to solve specific problems), and human-computer interaction (focuses on making computers universally accessible to people) belong to such very important sub-fields of computer science. 

Game theory has come to play an increasingly important role in computer science. Computer scientists have used games to model interactive computations and for developing communication skills. Moreover, they apply game theory as a theoretical basis to the field of multi-agent systems (MAS), which are systems composed of multiple interacting intelligent agents (or players). Separately, game theory has played a role in online algorithms, particularly in the k-server problem.

Interactive computation is a kind of computation that involves communication with the external world during the computation. This is in contrast to the traditional understanding of computation which assumes a simple interface between a computing agent and its environment. Unfortunately, a definition of adequate mathematical models of interactive computation remains a challenge for computer scientists. 

 
An online algorithm is the one that can process its input piece-by-piece in a serial mode, i.e. in the order that the input is fed to the algorithm, without having the entire input available from the start of the computation. On the contrary, an offline algorithm is given the whole problem data from the beginning and it is required to output an answer which solves the problem at hand.    

An animation of the quicksort algorithm sortin...

Image via Wikipedia

 (For example, selection sort requires that the entire list be given before it can sort it, while insertion sort doesn’t.) As the whole input is not known, an online algorithm is forced to make decisions that may later turn out not to be optimal. Thus the study of online algorithms has focused on the quality of decision-making that is possible in this setting.

The Canadian Traveller Problem exemplifies the concepts of online algorithms. The goal of this problem is to minimize the cost of reaching a target in a weighted graph where some of the edges are unreliable and may have been removed from the graph. However, the fact that an edge was removed (failed) is only revealed to the traveller when she/he reaches one of the edge’s endpoints. The worst case in study of this problem is simply a situation when all of the unreliable edges fail and the problem reduces to the usual Shortest Path Problem. This 

Johnson's algorithm for transforming a shortes...

Image via Wikipedia

 

 problem concerns detecting a path between two vertices (or nodes) of the graph such that the sum of the weights of its edges is minimized. An example is finding the quickest way to get from one location to another on a road map. In this case, the nodes represent locations, the edges represent segments of road and are weighted by the time needed to travel that segment.

The k-server problem is a problem of theoretical computer science in the category of online algorithms. In this problem, an online algorithm must control the movement of a set of k servers, represented as points in a metric space, and handle requests that are also given in the form of points in the space. As soon as a request arrives, the algorithm must determine which server to be moved to the requested point. The goal of the algorithm is to keep the total distance all servers move small, relative to the total distance the servers could have moved by an optimal adversary who knows in advance the entire sequence of requests.

The problem was first posed in 1990. The most prominent open question concerning the k-server problem is the so-called k-server conjecture. This conjecture states that there is an algorithm for solving the k-server problem in an arbitrary metric space and for any number k of servers. The special case of metrics in which all distances are equal is called the paging problem because it models the problem of page replacement algorithms in memory caches. In a computer operating system that uses paging for virtual memory management, page replacement algorithms decide which memory pages to page out (swap out, write to disk) when a page of memory needs to be allocated. Paging happens when a page fault occurs and a free page cannot be used to satisfy the allocation, either because there are none, or because the number of free pages is lower than a set threshold. 

 


Accumulate Your Vocabulary

September 25, 2010
2 Comments
                                          BGalina Vitkova   
 
  
          

Tips and steps

One of the most difficult work in studying a language is building and learning the language vocabulary. You should build your vocabulary all your life. But how? On the Internet and numerous English course books you can find ample tips and strategies that may help you in this sense.

In my opinion, based on my own experience and testing advices and recommendations of specialists in this area, the main, principal steps in building your own vocabulary are as follows: 

  • First of all, it is necessary to focus on several common ways to your vocabulary skills. Generally, building vocabulary goes from passive knowledge to active knowledge – by repeating a word so long until it becomes active vocabulary. This process requires time. So, be prepared for that and arm yourself with patience.
  • Learning vocabulary in groups of words appears to be much more effective than memorizing random lists. In this case words that are related to each other are more likely to be remembered over the long-term period.
  • The best way of learning words is to study and read systematically related texts and make a list of words of frequent occurrence.
  • Focusing on certain topics, which you are most interested in, brings good results, too;
  • For technical students and professionals such topics are comprised in technical texts typical and ultimate in their branch. Related activities include:
 
  • building a specialized list of common words appeared with high frequency in technical texts, which attract your attention,
  • building a list of professional words, expressions, collocations used in your branch,
  • building a list of words used in common communication (radio, TV, magazines, journals) to be able to understand discussions on topics that concern you;

After building such lists you can memorize them successfully.

Vocabulary Trees                                 

Vocabulary trees provide a solid ground for building your vocabulary and enhancing its level. People, especially students very often learn a new vocabulary by simply writing lists of new vocabulary words and then memorize these words by heart. Unfortunately, this technique generally brings only few positive consequences. Such learning helps you to pass exams, different tests, interviews etc. It leads to open up a kind of “short term” remembering. Vocabulary trees, on the other hand, provide a clue to “long term” memorization by placing vocabulary in connected categories. The example of a vocabulary tree on the right is taken up from http://esl.about.com/ .

A concept of vocabulary trees is applied in Improve Vocabulary with Vocabulary.Net Builder, which is strongly recommended to try. Enjoy the citrates from this publication:

“English vocabulary level has been shown to be strongly related to educational success. In addition, it is related to the level of occupation attained“. Bowker, R. (1981).

“A rich vocabulary is a valuable asset and an important attribute of success in any walk of life …”. Elley, W.B. (1988).

Vocabulary Tables

Vocabulary tables can help you in enriching your vocabulary based on different forms of a particular word that is known to you. If you build regularly vocabulary tables based on specific topics, namely in our case on technical topics, which you study or work in, you will certainly improve your knowledge of English.

Building tables on specific topics also helps to improve “long term” memory of related words. See below an example of such a vocabulary table based on words related to the post Speech and Handwriting Recognition in Windows 7 , which is the most popular last weeks:

NOUNS VERBS ADJECTIVES ADVERBS
availability, availableness   available availably
computer, computation, computerisation, computability compute, computerise computable,  computerisable,    
change change changeable changeably
implementation implement implementable  
improvement improve improvable  
recognition, recognisability recognise recognitive, recognisable recognisably
use, usage, usability use usable  

 

850 Words for Basic Conversational Fluency

Even if learning words from casual lists is certainly not the most effective method for long-term word remembering, it is very helpful to know what words are the most usable in English. It provides you with a good roadmap in studying the language. A list of such 850 words was published in 1930 in the book by Charles K. Ogden named Basic English: A General Introduction with Rules and Grammar.

The book contains basic verbs, articles, pronouns, prepositions, etc. split into categories. These 850 words should give you a solid basis for conversation. For more information about this list you can find in Ogden’s Basic English page. In any case, this list is an excellent starting point for building up a vocabulary that allows you to converse fluently in English.

Below the hyperlinks to these 850 Words are given:

Basics (verbs, articles, pronouns, prepositions, etc.)
General Nouns 1 – 200
General Nouns 201 – 400
Specific Nouns 1 – 200
Adjectives 1 – 150

For more advanced vocabulary building that helps you quickly improve your English study Kenneth Beare (http://esl.about.com/) recommends these vocabulary books. They will help you enhance your vocabulary, which is especially important for professional English knowledge.

 Use more your Dictionary

Since you can use it not only for finding words, but also in order to explain meanings of words, to improve your pronunciation by hearing words, in order to check spellings of less-known words and spelling variations, to find synonyms and more. Drop a look again at Dictionary – your best helper in mastering English words . There you will find the detailed information of possible usage of dictionaries for building your specialized vocabulary.

Read more about the topic at http://socyberty.com/languages/who-wants-to-improve-the-vocabulary/#ixzz0zzVciIw1 .

References

PS:

  • It is very helpful to be aware of what kind of the English reader you are. Complete Personality Quiz – What Kind of English Learner Are You?
  • Build your vocabulary and study English in compliance with your type of the English Learner!
  • In Free Rice you can find a very nice game that helps you in learning English words. English grammar and other topics. At the same time the game will entertain you.

 

 


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