Top 32 Apps Similar to Analisa RAB (ADFREE)

ConstruCalc
Calculates accurately the building materials of your workorrenovation.
Bridgemate 3.4.3
Real-time information on your results and rankings duringyourbridge games.
Walls... and Frames XXI
Calculation of reinforced concrete walls and frames. WHITHOUT ADS.
Construction Calculator 2.0.1.3
Will Maze
Construction Calculator - your assistant in the housebuildingormaintenance!
RCC Slab Design 3.0
A simple App for optimum design of Reinforced Cement Concrete(RCC)One-Way & Two-Way Slabs in all combinations of Edgesupportsconditions and various options of Cover, Grades of ConcreteandSteel. Optimisation option for any given rates of ConcreteandSteel.
Beam calculator XXIX
Beam calculator calculates bending moments, shear forces,anddeflections.
RCC Slab Design - Civil Engine 3.1.10
eigenplus
One Way and Two Way RCC Slab Design app (IS 456:2000 | LimitStateMethod).
RCC Column Design - Civil Engi 2.1.12
eigenplus
☆ RCC Column Design (IS 456:2000 | Limit State Method) app forCivilEngineers.
Construction Material Estimate 1.8
The Application to estimate/calculate the construction materialsforBuildings
Section Design 4.0.1
Reinforced concrete design
Doka Tools 2.2.0
Doka GmbH
The Doka Tools app is a digital calculation tool for yoursite.Time-consuming, labour-intensive methods of calculating theoptimumequipment quantities are now a thing of the past. With DokaToolsyou can plan wall and floor formwork: it takes just a coupleofseconds to optimise the components for Dokaflex and to work outthepermitted rate of placing and maximum fresh-concretepressureduring pouring. Mobile formwork planning With Tipos walland Tiposfloor planning systems you can form in simple componentsin no timeand quickly get an overview of how to best utilise Dokaformworksystems. Layout and planning views of your Doka formworkalong withthe entire piece list and design values appear on yourdisplay inlittle more than the blink of an eye. Gives a boost toefficiencyNo matter which Dokaflex floor-slab system you are using,theDokaflex calculations let you optimise the type and the spacingofthe necessary beams and props, in just a fewmouse-clicks.Digitally calculating the pouring rate The rate atwhich concretecan be placed has a very great influence on thespeed, and thus onthe economic efficiency, of CIP concreting work.The DokaFresh-Concrete Pressure Calculator is a quick and easy waytocalculate the permitted rate of placing and max.fresh-concretepressure. FEATURES - Tipos floor - Tipos wall -Dokaflex 30 tecdesign calculation - Dokaflex optimisation -Fresh-ConcretePressure Calculator - ‘Share’ functions for allcalculations ABOUTDOKA Doka is one of the world leaders indeveloping, manufacturingand distributing formwork technology foruse in all fields of theconstruction sector. With more than 160sales and logisticsfacilities in over 70 countries, the Doka Grouphas a highlyefficient distribution network which ensures thatequipment andtechnical support are provided swiftly andprofessionally. Anenterprise forming part of the Umdasch Group,Doka Group employs aworldwide workforce of more than 6000.
Concrete Calculator 5.01
A simple tool to calculate how much concrete is neededforpouringslabs, footings, columns and steps. Concrete Calculatoris afreecalculator with the following functionalities:-Calculatecement,sand and aggregate amount in concrete. -How manypremixconcretebags required for your project. -Option to set yourown bagsizeand rate of premix bags. -Calculate Blocks (bricks)countneeded tobuild a wall by area. -Plastering Calculator.-Calculatethe weightof rebar -Metric or imperial Units supportDeveloped withanintuitive interface. It means less click, fastresults.Appremembers your settings for next use. Other FeaturesofConcreteCalculator - Internet connection is not required. -Smallapk size.- No background process. - Share or Save function. -Fastandsimple. - Better tablet support. - Totally Free. **ThisConcreteCalculator should be used as an estimating toolONLY.Applicationis not responsible for any discrepanciesoncalculations. **
Mycrete 1.0
civil4m
Mycrete do engineered concrete design asperguidelines of IS:456.As we all know properties of materials differs from region toregionso we have also considered this factors in ourdesignparameters.We support design of concrete from M10 to M40 for all typesofcondition.This app is build more user friendly for understanding andquickprocessing.We assure user the mix design made using this app are moreaccurateand economical.Purpose of this application is to make engineers approachtowardsconcrete more qualitative and insisting on usingengineeredconcrete.Its always better to use engineered concrete rather thanusingconventional systems of concreting.Mycrete does mix design over the data provided by the user.So to get accurate and reliable mix design user need to putthecorrect data in it.When you get the mix design after submitting data do notusedirectly on large scale. The user expected to do trail concreteandcheck for desired results are achieved before using it.Our programs only support super plasticiser as admixture whichhavecapacity of 20 liters water reduction. If dosage of admixturegoesabove 1.5% users should check its effect on setting timeofconcrete by doing trails. As per IS admixture should not beusedabove 2%, if admixture quantity in your design exceeds thesaidlimit user is requested to use high range waterreducingadmixture.IS:456 allows maximum cement content per cum as 450kg/cum.Mycrete is more powerful and accurate mix designing appwhichenables you to get design suitable at your location inindia.Mycrete is more powerful and accurate mix designing appwhichenables you to get quality concrete design suitable atyourlocation in india.Concrete design civil engineering quality toolsHappy engineered concreting
KSI RC Design 2.0
RC Structure Design Application for Civil Engineering.
Isolated Footing 4.0
TechAchiever
An application for easy design of RCCIsolatedFooting.A simple application for design of reinforced cementconcreteisolated pad footing . This application provides design ofanIsolated Footing in seconds with two different list ofanswers:1) Main answers - Includes area of footing , main anddistributionreinforcement , check results.2) Detailed answers - Includes all that information you need toknowfor successful design of Isolated Footing.
Concrete Mix Calculator 1.0.5
Concrete, Mortar and Plaster Calculator. The one you need!
Concrete Technology 7
The app is a complete free handbook of ConcreteTechnologywhichcovers important topics, notes, materials, news& blogs onthecourse. Download the App as a reference material& digitalbookfor Civil & environmental engineering programs&degreecourses. This useful App lists 60 topics withdetailednotes,diagrams, equations, formulas & course material,thetopics arelisted in 8 chapters. The app is must have for alltheengineeringscience students & professionals. The appprovidesquickrevision and reference to the important topics likeadetailedflash card notes, it makes it easy & useful forthestudent ora professional to cover the course syllabusquicklybefore an examsor interview for jobs. Track your learning,setreminders, edit thestudy material, add favourite topics, sharethetopics on socialmedia. Use this useful engineering app asyourtutorial, digitalbook, a reference guide for syllabus,coursematerial, projectwork, sharing your views on the blog. Someof thetopics Covered inthe app are: 1. Cement 2. Manufacturingprocess ofcement 3.Chemical composition of Cement 4. Grades ofCement 5.Tests andPhysical Properties of Cement 6. Concrete 7.Admixtures 8.MineralAdmixtures 9. Chemical Admixtures 10. Usage ofAdmixtures11.Introduction to Aggregates 12. AggregateCharacteristics13.Fitness Modulas 14. Maximum size vs. Nominalmaximum sizeofaggregates 15. Adsorption and Moisture content ofaggregates16.Specific gravity, Bulk density and porosity ofaggregates 17.Shapeand Texture of Aggregates 18. Deterioussubstances inaggregates19. Alkali aggregate reactivity 20.Soundness test foraggregates21. Introduction to Workability 22.Factors affectingWorkability23. Measurement of Workability 24.Segregation andbleeding 25.Manufacturing of Concrete 26. Quality ofmixing water27. Water/cement ratio 28. Gel-space ratio 29. Maturityconcept ofconcrete30. Influence of properties of coarse aggregateon strength31.Relation between compressive and Tensile strength32.Acceleratedcuring test 33. Aggregate cement bond strength34.Testing ofhardened concrete 35. Factors affectingcompressivestrength 36.Compressive strength test 37. Flexurestrength test 38.Splittingtest 39. Nondestructive Quality Test 40.Pull out test41.Elasticity 42. Poisson’s ratio 43. Shrinkage 44.Creep 45.Mixdesign 46. Factors affecting Mix design 47. ExamplesofConcreteMix proportioning 48. Durability of Concrete49.Acceptancecriteria for Concrete 50. BIS method of Mixproportioning51. Lightweight aggregate 52. Autoclaved Cellularconcrete 53. Nofinesconcrete 54. High Density concrete 55. Fibrereinforcedconcrete56. Polymer Concrete 57. Polymer Concrete 58.Types ofPolymerconcrete 59. High performance concrete 60.Self-compactingconcreteEach topic is complete with diagrams,equations and otherforms ofgraphical representations for betterlearning andquickunderstanding. Concrete Technology is part ofCivil&environmental engineering education courses andtechnologydegreeprograms of various universities.
Structural Design Enginerring 1.0
Shael
Structural Design Enginerring application is completely freeandusefull application of structure engineering learningBasicallythis app is handbook, easy to use , works offlineStructural DesignApps This app covers all important topic. Its likea book forstudents, a co worker guide for engineers. The objectiveof the Appis to bring faster learning and quick revision of thetopics. Sometopic covered by this application are : Reinforcedconcrete : as acomposite material, has occupied a special place inthe modernconstruction of different types of structures due to itsseveraladvantages. Concrete :Concrete is a product obtainedartificiallyby hardening of the mixture of cement, sand, gravel andwater inpredetermined proportions. Depending on the quality andproportionsreinforcing steel Ultimate load method (ULM) One-way andTwo-waySlabs Doubly Reinforced Beam T−beams and L−beams LimitingMoment ofResistance Design of Staircase :The staircase is animportantcomponent of a building, and often the only means ofaccess betweenthe various floors in the building. It consists of aflight ofsteps, usually with one ormore intermediate landings(horizontalslab platforms) provided between the floor levels.Design strengthof materials Compression members are structuralelements primarilysubjected to axial compressive forces and hence,their design isguided by considerations of strength and buckling.Examples ofcompression member pedestal, column, wall and strut.LongitudinalReinforcement Slender Columns Design of isolated columnfootingSafety at Ultimate Limit State in Flexure Masonry : is oneof themain items of construction in a building and needscarefulconsideration. Design Shear Strength of Reinforced Concrete:Recentlaboratory experiments confirmed that reinforced concrete inbeamshas shear strength even without any shear reinforcement. Bond:Thebond between steel and concrete is very important and essentialsothat they can acttogether without any slip in a loadedstructureNumerical Problem
Electrical Calculations 9.2.1
This app is essential for an electrician
Concrete Mix 3.0.1
AppsGear
This app is a complete solution of concrete estimation, mixdesign& many more.
Binder - Concrete Calculator 1.6
despDev
Concrete calculator will help to estimate ready mix concreteandpremixed bags
Material Estimator for Civil C 1.3
Aman Bhatia
Estimation of various construction material
Ambuja Foundations 1.1.0
The AKC App is your one stop learning resource forthecement,concrete and construction industry. Through this app,yougetaccess to the latest learning materials likecasestudies,articles, e- books and other literature. Along withthis,the AKCapp gives you information and invites tovariouslectures,workshops and sessions conducted by Ambuja Cementsfromtime totime. Keep your knowledge and skills updated withallresourcessent straight to your pocket via the AKC app!
Flooring Job Bid Calculator 1.3.1
DMA APPS
Flooring Job Bid Calculator Free is here to help you with allofyourfloor measuring and bidding needs. !!NEW!! with V1.3.1August17th,2016. Issue with single digit Inches not beingcalculated insquareyards calculator. V1.3. August 8th, 2016.Metric TileCalculatorSquare Meters M² Calculator Improved SquareFeet andSqure YardsCalculator Tile Calculator allows you tocalculate theamount oftiles you need for a few areas of floor, andlets youcalculate thecost of these tiles. This app incorporatesmany ofthe differenttypes of costs associated with flooringinstallation.You cancalculate a flooring bid that includes CeramicTile,Hardwood Floors,Carpet, Vinyl, Laminate Flooring, and others.Youcan calculate allaspects of the job from take up to install,andextra charges aswell. You can save your jobs and bids. Thenreloadthem later withevery piece of information saved. You canemail thedetails of theflooring bid. Which is the totals in aformattedemail/text message.All the floor details will beincluded. Theeasy step by step processwill guide you to anaccurate bid to helpyou land the job, or ensurethat you are beingcharged a fair andaccurate price on your floor.You can also usethe calculators tofigure simple square feet andyards withadditional wastepercentages added. Then you can enteryour chargesand calculatethe total all on the same screen. You willstart theproject in theMain Menu area. Here you will have someoptions. Asyou "calculate"each section. It will automaticallyupdate the JobTotal in theFinal Bid section of the app. This is thedifferentpage breakdown:Job/Customer Details Page: You can add thecustomersaddress. Homeand Cell Phone Numbers as well as City andZip. Youcan thenemail/message this information easily from the appwith thetotalfloor bid total included. Square Foot CalculatorPage:(To HelpGetYour Totals) Here you can add up a few quickmeasurementtotals.There are a few sections for Area and Width thatwillcalculate atotal. Then you can add square feet to it in the"KnowSquare Foot"Area. Also, you can add the percentage of squarefeetthat you wantadded to that total. This is just a "squarefeetcalculator". It isnot added to the FINAL BID AREA. Take UpChargesPage:(Estimator)This can help you add up the different typesofflooring take-upyou may have. There are sections for CeramicTileFlooring , Vinyl,Hardwood Flooring, Carpet, Laminate, andOther.You can addindividual square feet totals, and prices to eachtypeof floorthat you want to include in the flooring bid. Thisisautomaticallyadded to the floor bid total. Prep &PlywoodPage:This page isto calculate some flooring prep items, andtocalculate sub floorcost. Here you enter the amount of squarefeetof floor that youneed to put underlayment/sub floor down on.Enterthe square feetper sheet and the amount you charge per sheettoinstall and itwill calculate the number of sheets you need, andthetotal amountto install them. The amount of sheets is a netamount.You willneed more to actually install the job. Extra ChargesPage:Herethere are areas you can add things to the bid such aschargesformoving furniture, hanging baseboard, moving andresettingtoilets,and moving appliances. Install Charges Page: Theinstallchargespage is where you enter the actual square footageyouareinstalling of each type of floor. There are sectionsforCarpet,Vinyl, Ceramic Tile, Hardwood, Laminate, and an otherformoretypes of flooring. These will all be totaled, and yourtotalsquarefootage and your total install cost will be transferredtotheFINAL BID AREA. Final Bid Page: Here the totals from alltheotherareas, Take Up Charges, Prep and Underlayment, ExtraCharges,andInstall charges are all added up. There is one morefield herethatwill be added to the total. It can be used foranything.Supplieslike seam tape, seam sealer, grout mortar.
NPTEL : Civil Engineering
Would you like to learn CivilEngineering(CIVIL) by IIT professors at any time and place? If yes,then youare at right place.Use NPTEL Civil Engineering App to understand your subjectsbetterusing video lectures and PDFs and make your conceptstronger.Using NPTEL Civil Engineering app you can read text content (PDF)ofall videos which helps you to save mobile data.***************************************************************************NPTEL Civil Engineering App has following features:(93Subjects)• Videos tutorials by IIT professors.• It includes PDF version of videos, so if you have slowinternetspeed then you can read PDF content.• We are committed to add new tutorials regularly and providethebest experience to all users• App is completely free of charge with minimal ad on it.This app covers following subjects in detail1. Advance Geotechnological Engineering2. Advanced Foundation Engineering3. Advanced Foundation Engineering4. Advanced Geotechnical Engineering5. Advanced Hydraulics6. Advanced Hydraulics7. Advanced Hydrology8. Advanced Structural Analysis9. Advanced Techniques in Geotechnical andFoundationEngineering10. Application of Soil Mechanics11. Applied Elasticity for Engineers12. Civil Engineering - Building materials and Construction13. Concepts in Geotechnical and Foundation Engineering14. Computational Hydraulics15. Composite Materials16. Concrete Engineering and Technology17. Concrete Technology18. Construction Planning and Management19. Design of Concrete Structures20. Design of Reinforced Concrete Structures21. Design of Steel Structures22. Design of Steel Structures I23. Design of Steel Structures II24. Engineering Geology25. Environmental Air Pollution26. Finite Element Analysis27. Finite Element Analysis28. Finite Element method for vibration and Stabilityanalyses29. Fluid Mechanics30. Foundation Analysis and Design31. Foundation Engineering32. Geo-informatics in Transportation Engineering33. Geosynthetics and Reinforced Soil Structures34. Geosynthetics Engineering: In Theory and Practice35. Geotechnical Earthquake Engineering36. Geotechnical Earthquake Engineering37. Geotechnical Earthquake Engineering38. Global Positioning System39. Geotechnical Measurements & Explorations40. Ground Improvement Techniques41. Ground Water Hydrology42. Hydraulics43. Hydraulics44. Infrastructure Planning and Management45. Introduction to Engineering Seismology46. Hydrological Measurements and Analysis of Data47. Introduction to Transportation Engineering48. Mechanics of solids49. Modern Construction Materials50. Modern Surveying Techniques51. NOC:Earth Sciences for Civil Engineering52. NOC:Engineering Graphics53. NOC:Geology and Soil Mechanics54. NOC:GPS SURVEYING55. NOC:Introduction to Geographic Information Systems56. NOC:Principles and Applications of Building Science57. NOC:Probability Methods in Civil Engineering58. NOC:Project Planning & Control(Course sponsoredbyAricent)59. NOC:Structural Dynamics60. NOC:Sustainable River Basin Management61. Numerical Methods in Civil Engineering62. Optimization Methods63. Pre-stressed Concrete Structures64. Pre-stressed Concrete Structures65. Probability Methods in Civil Engineering66. Probability Methods in Civil Engineering67. Reliability Engineering68. Remote Sensing69. Rock Engineering70. Seismic Analysis of Structures71. Site Characterisation & Instrumentation72. Soil Dynamics73. Soil Dynamics74. Soil Mechanics75. Solid & Hazardous Waste Management76. Stochastic Hydrology77. Stochastic Structural Dynamics78. Strength of Materials79. Structural Analysis II80. Structural Analysis II81. Structural Dynamics82. Structural Reliability83. Surveying84. Transportation Engineering II85. Urban transportation planningand many more...All credit goes to professors of NPTEL and this app isforrepresentation purpose only.
ConCalc - Concrete Calculator
Luso Studios
ConCalc - A free concrete volume (CubicYards)calculator that makes if easy to calculate the cubic yardsneededfor a variety of concrete structures like a pro. Anyprofessionalor Do it Yourself person (DIY) will appreciate how easyit is tocalculate structures that include slabs, curbs, walls,footings andcolumns.ConCalc also keeps a running total allowing for multipleindividualcalculations and a grand total of cubic yards. A historyof allcalculations is also displayed on the main screen allowingfor easyreference.Special Features:- Share or Save your work to any supported app in your device- US or metric units- Even more Concrete structures- Keeps a running total of volume (cubic yards).- Maintains a history of all calculations.- Better tablet support* This is the free version. If you prefer no ads, you maypurchaseConCalc+.
Somany Ceramics Ltd. 2.4
Features:- 1) Product Catalog - Wall & Floor Tiles,BathFittings& Sanitaryware 2) Add to favorites and send listoffavoriteproducts for enquiry to Somany Customer Care 3)ShareSomany Productsvia Facebook, whats app, email and othersharingmedia 4) Somany NewsUpdates 5) Locate nearest SomanyDealer/Store6) View crawledproducts in offline mode. SomanyCeramics Ltd, theflagship companyof Late Shri. H. L. Somany group,is one of theleading players inthe tiles and sanitary wareindustry. Recently,Somany Ceramics Ltd.,was presented with TheAmerican CeramicSociety’s (ACerS) CorporateTechnical AchievementAward 2014 forthe development of Veil Craft(VC) Shield Floor Tileshaving VeilCraft technology, for whichSomany has patent rights.Earlier,Somany Ceramics has been awarded“Asia’s Most PromisingBrand” inthe ceramic tile industry, which isgiven to the mostadmired brandof the year. It has also been awarded“The PowerBrands Award” for2010-11, which represents India’s mostpowerfulbrand as chosen bythe consumer and “The Indian Power Brand”for2011-12 which is atestimony to being a true global Indianbrand.Somany received in1996 recognition from the Government ofIndia forits R&Ddepartment (a first in the tile industry) andwas thefirst tilecompany to be awarded ISO 9002 certification in1998. Itis alsothe first in the industry to be felicitated with theBISmarklicense for the best quality products. Somany hasachievedISO14001 in 1999 for environment friendly facilities.Somany islistedon the NSE and BSE, and has over 4,000 shareholders.
Home Ceiling Design Ideas 1.0
Farrapps
Plafon minimalist - In years goneby,peoplewere aware that unique ceiling designs were as importantasthedesign of the rest of the house. This is not so truetoday.Manyhomeowners do not place the same importance on theceiling assay,the floors. However, with some creativity, uniqueceilingdesignscan really give your rooms and home an amazingandunforgettablelook. coffered ceiling and ceiling fans withlightsare likecontemporary in your home designs.Drop ceiling gypsum - While most ceilings are flat andmirrorthesize and shape of the floor, there are many ceilingsthataresloped, domed, have exposed interior beams, airconditioningductsor other beams and wiring in awkward or unsightlyplaces.Theseelements need to be worked with and incorporated intoyourceilingdesign plan, not covered up. Covering these kinds ofissueswillusually stand out more if not dealt with properly, so usetheminyour plan and you will have the best solution. Gypsum,fakes,dropand stretch film ceiling designs are very wonderful.Liketeenagebedroom design ideas, best ceiling is very importanttocreate yourhome interior become more wonderful. Hunter ceilingfansand falseceiling designs are like great wall art designs.Drop ceiling plafond - Ceiling illusions can cover upflawsandenhance any room. If the ceiling is lower, you can makeitseemhigher and with a high ceiling, you can make it seem tocomedownand be more personal if you'd like. The height oftheceilingshould be proportionate to the size of the room, butthatdoes notalways happen. Unique ceiling designs can really helptochange theatmosphere and character of a room to make it amoreenjoyablespace to be in.Luxury, modern, rustic, tile and wood designs - Therearemanydecorative elements that you can use, likeceilingmedallions,ceiling rims, beautiful molding and even ceilingdomes.Take a goodlook at your ceiling and try to get an idea ofwhat kindof feelyou think it should have. Do you want it to feelfree andopen orcozier? Once you have a good idea of the feel youwant, youcanstart to build a design that will reflect thatmood.Large, small and master Ceiling Designs - Molding isareallygreat design element that can be used to createinterestingandunique ceiling designs. To start with, it can be usedwithjustabout any of the other great ceiling applicationslikelightingfixtures, painting and art applications,medallions,friezes, beamsetc. Flexible crown molding comes in justabout everystyle andranges from the rather simple to the extremelyornate. Youcan evenhave your flexible crown molding customdesigned! This isanespecially great option if you already havebeautiful carvingsorplaster work that you would like to match.Design of moderngypsumis like your minimalist door design in yourdream house. Thedesignis very interesting like bathroom design,patio design, andalsoyour home exterior designs.Simple and easy designs - If your space has roundedwalls,thenflexible crown molding is a must have. What is sogreataboutflexible crown molding for your unique ceiling designsandwalldecoration is that it is easy to install, it is lightweight,butnot fragile, it is easy to manipulate and easy totransport, itcanbe treated similar to light wood, you can paint it,the materialitis made of is quite hard, strong and resistant, it'ssize willnotdeteriorate and it comes in a large variety of shapesandsizes.drop ceiling tiles and false ceiling design are great.Classic, vintage, country, and also Unique ceiling designscanbeaccomplished with the help of flexible crown molding aloneorinaddition to other design elements.
Break Bricks
CanadaDroid
Break Bricks is #1 highly anticipatedarcadegame filled with endless charm and brilliantly designedlevels.With new power-ups smartly layered onto the classicgameplay, BreakBricks is more challenging and engaging.Familiar to play, yet hard to master, Break Bricks bringsfreshchallenges and unanticipated obstacles to breakout hunterageplayers around the world. In this entrancing game of skillandspatial awareness, it is your job to destroy all the bricks.Byusing the walls and the paddle below, try your best to ricochettheball against the bricks and knock down them to extinction.Watchout the challenging bosses (temple shape, dino shape &etc.)every 30 levels.Game Features:- Two set of console quality graphics (classic shores &deadlymetal)- Intuitive touch controls with realistic physics- Arcade mode & Endless mode (don't run out of time)- 150+ challenging levels to complete
Structural Beam (DEMO) 59
A fast Calculator for Structural Calculations
JWDTools (Engineering Tools) 3.0
JWDStructure
A set of structural engineering and mathematical tools
Solid Color Wallpapers 5.1
Ldinka
Beautiful Color Wallpaper. Choose any color, textures, gradientandpattern.