2012 AISTech Conference Proceedings

50 m/s in Cooling Bed to Enhance Profitability in Rebar Production

A Kinetic Oxidation Model for High-Strength Steel

A Mathematical Model for the Carbothermic Reduction of Dust-Carbon Composite Agglomerates

A Method for the Determination of Shape Actuator Capabilities Envelopes in 20-High Cluster Mills

A Novel Approach for Coupling Slag Infiltration to Metal Flow, Solidification and Mold Oscillation on a 3D Model for Continuous Casting of Slabs

A Review of Emerging Trends in Mobile and Wireless Technology for Maintenance and Reliability in the Steel Industry

A Review of the Rhomboidity Problem in Billet Casting

A Sensible Route to Energy Efficiency Improvement and CO2 Management in the Steel Industry

A Strip Crown Model Based on the Finite Element and Response Surface Methods

A Study of Ca-Modification Process in Al-Killed Steels

A VPP Success Story: Making OSHA 10 Work for You

Activity of SiO2 in SiO2-Al2O3-CaO Slags in Equilibrium With Fe-Al Melts

Addressing Transverse Cracking Problem in Slab Casting

Advanced Analysis and Quantification of Hot Rolled Strip Microstructures by EBSD

Advanced Strategies for Levelling for High-Strength Heavy Plate Production

Advances in Roll Scanning Technology - A New Method for Eddy Current Defect Detection

Advances in the CFD Modelling of Raceway Injections

AlN Formation in High Aluminum Content Fe-Al Alloys

Aluminum Deoxidization of H13 Hot Die Steel Through Inert Gas Protection Electroslag Remelting

An Advanced EAF Optimization Suite for 420-t Jumbo DC Furnace at Tokyo Steel Using DANIELI Technology

An Integrated System for Minimizing the Downtime for Dimensional Changes in Bar Rolling Mills

Another Step Forward to the Best Quality Wire Rod ??ith Better Productivity and Higher Efficiency

Application of Large Capacity Voltage Source Inverter to Cylindrical Rotor Synchronous Motor

Arvedi ESP - First Results and Business Cases

Assessing Inclusion Removal in a Steelmaking Ladle: Plant Assessment and Modeling

Automatic and Online Oil Film Monitoring

Automatic Ladle Gas Coupling Systems

Automatic Roll Loaders for Intelligent Roll Shops

Basic Concepts for an Integrated Steel Process Control System

Benefits of Advanced Configuration and Simulation Study

Bi-Reflectance Mapping and Automated Petrographic Analysis of Metallurgical Coke

Brazilian Potential of Biogas Use as Fuels in Metallurgy

Calcium Corrosion of a Zirconia Slide Gate Refractory

Calibration of Thermal Models of Continuous Casting of Steel

Campaign Life Extension at ROGESA Blast Furnaces by Co-Injection of PCI and Titanium Dioxide

CFD Modeling of Complete Reheating Furnaces

Challenges for Modeling Compliance With Short-Term SO2, NO2, and PM2.5 Ambient Standards

Changes to NFPA 70E 2

Characteristics and a Novel Quantitative Model of Macrosegregation in Continuously Cast High-Carbon Steel Billets

Characterization of Mixtures of Sugarcane Bagasse and Charcoal for Injection Through Tuyeres of Blast Furnaces

Classification of Fine Ores Regarding Their Reducibility With Tests in a Lab Scale Fluidized Bed Reactor and Petrographical Analysis

Coil-to-Coil Joining With Laser Welding in Particular for Sophisticated Steel Grades

Coke Battery Pushing Emission Reduction - Improvements in Transfer Car Design at U. S. Steel Canada Inc. - Lake Erie Works

Coke Making Process Improvements Through Culture Change and Total Process Reliability

Coke Without Coal: More Than Half-Century of Production in Argentina

Cold Rolling of Metal Foils by Means of Ceramic Work Rolls

Collaborative Mobile Maintenance Method for Reclaimer

Combined Utilization of Condition Monitoring and Real Time Numeric Simulation for a Condition Forecast Oriented Maintenance Strategy

Combining New Coke and Ironmaking Technologies to Reduce the Carbon Footprint in the Production of Steel

Commissioning of 565 kg, 18 Inch-Wide Pilot-Scale Movable Wall Coke Oven at Coal Science Laboratories

Comparison and Integration of the Ukrainian Project Life Cycle Process With a Western Front End Loading Process

Comparison of the RH and Tank Degassing Processes

Comprehensive Control of a Reheating Furnace

Comprehensive Electrics and Automation Solutions for Brazil’s Most Modern Steel Plant

Continuous Enhancement of the Evraz Superheat Model Control for Slab Casting

Continuous Monitoring of Liquid Level and Thermal State in the Hearth Based on Measurement of EMF on the Blast Furnace Shell

Conversion at the Luna Plant in ABS, Italy: 45 Days From Last Rectangle to First Round Bloom Cast

Cooling Technologies for Roughed and Finished Strip

Crack Initiation and Propagation of Galvanized Coatings Under Bending Loads

Cradle to Cradle at CSC: Through Integrated Recycling System and Industrial Symbiosis

CSP® Flex - New CSP® Concepts for Future Market Requirements

Danieli Cold Mill Complex Turboflo® Pickling Coupled to 6-High Mini Tandem Mill for Automotive Applications

Danieli Contributions to the Development of Thin Slab Casting and Rolling Process: From first generation Plants to the Recent World Record Breaking Applications

Design, Construction, Commissioning and Operation of the New Blast Furnace No. 6 at AHMSA

Desulphurization of Liquid Steel in Ladle Furnace

Desulphurization Strategies in Oxygen Steelmaking

Determination of Flow Instabilities Inside a Continuous Casting Mold by Particle Image Velocimetry and Computational Fluid Dynamics

Development and Implementation of an Online Process Model for the Control of Steel Chemistry and Superheat During Secondary Steelmaking

Development of Compact Regenerative Burner in Hot Rolling Mill

Development of EAF Dust Injection Technology in Aichi Steel

Development of Improving of Surface Qualities of Hot-Dip Galvanized Products by Electromagnetic Strip Stabilizers

Development of Intelligent Machine Condition Monitoring and Diagnostic System in CSC

Development of New Combustion Control System Based on Fuel Gas Humidity at Continuous Annealing Line

Development of New Materials Based on On-Site and Laboratory Evaluation Methods for Understanding Work Roll Surface Degradation

Development of New Sealing System at Roller Bearing in Continuous Caster Roll

Development of Non-Destructive Crack Inspection Technique for Conveyance Roll Using Vibro-Thermography

Development of Pass Schedule Software Using a Slip-and-Stick Non-Circular Arc Force Model

Development of Roll Type Continuous Slag Solidification Process

Development of the High-Speed Thin-Slab Casting Technology of POSCO

Development of the Third-Generation FC Mold by Numerical and Water Model Simulations

Development of TMCP Steel Plates for Hydraulic Supports Used in Mining Machinery

Dioxins Minimisation and Control in a EAF

Direct Heat Treatment After Hot Rolling of a High-Strength and High-Toughness Plate Steel

Dry and Inorganic Tundish Coating Refractory

Dynamic Argon Control

EAF Equipment Redesign for Maximum Operational Performance and Extended Component Life

EAF Slag: A Product No Longer a Problem

Effect of Non-Uniform Roll Cooling on Hot Bands Crown and Flatness in Finishing Stands

Effect of S Concentration on Inclusions Entrapment in Solidified Shell

Effect of Silicon on Hot Shortness

Effective and Flexible Rolling Mill Automation Upgrades

Effective Lubrication Solutions for Steel Mill Equipment

Electrical Arc Flash Safety and Risk Management

Electrode Consumption in a Modern High-Power Electric Steel Shop

Electromagnetic Devices for Limiting Currents for Starting Large Motor and Fault Currents

Elimination of Full Face and Edge Cracking in Hot-Charge Plate Rolling

Energiron Direct Reduction Process: The Forefront Technology

Energy Saving Drives for Hot Strip Mills

Engineering Aspects and Results for VHD Technology

Evaluate and Model the Efficiency of a Blast Furnace Gas Cleaning Plant Using Computational Fluid Dynamics: Geometry Optimisation of a Gravity Dust-catcher

Evaluation of Alternatives to Raise the Blast Temperature at Lean Blast Furnace Top Gas Operation

Experience With Long BOF Campaign Life and TBM Bottom Stirring Technology at Meishan Steel in China

Experimental Investigation Into the Influence of Ti on the Clogging of ULC Steels in Continuous Casting

Expert Operator Control for Increasing Safety, Productivity, and Operability of Cranes

Extending Wireless Technology For Remote Control of Crane Brakes, Equipment Monitoring and Encoder Feedback

Flameless Oxyfuel Slab Reheating Experiences

Flexible Gas Mixing Station Design and Operation for Natural Gas, Coke Oven Gas and Blast Furnace Gas Mixtures

Flexible Groove Sequences for Hot Rolling a Number of Materials

Focus on Vacuum Degassing

Formation and Evolution of Inclusions in Al-Ti-Mg-Deoxidized Steel

Free Opening Performance Under Longer Residence Time of Steel Ladle at ArcelorMittal IHE Steelmaking

Fujico’s CPC/HSS Roll Performance at CMC’s Arizona Micro-Mill and in North America

Further Study of the Blown Grain Condition

High HP DC Drives Replacement or Digital Front End (DFE) Upgrade on Rolling Mills

High-Temperature Mold Powder Viscosity: Basic Experimental Procedure and Quantitative Analysis

High-Temperature Performance Comparison of Lump Coal, Coal Briquette and Coke Used As COREX Fuel

Hot Strip Mill - Streamlining for Increasing the Capacity and Improving Quality

How to Make the Plants of Today Comply With the Requirements of Tomorrow

How Upgrades in Makeup Quality and Treatment Program Dramatically Improved BOF Hood Uptime/Caster Mold Reliability

iEAF® Technology: The Use of Offgas Analysis for Carbon and Temperature Prediction in Electric Arc Furnaces

Impact of Non-Polygonal Ferrite Microstructures on Technological Properties of CSP® Processed Low Carbon Micro-Alloyed Steels

Implementation of the Chemical Energy Control Module at Nucor Yamato Steel EAF2

Importance of Advanced High-Strength Steels and Electronic Units on the Recycling of Automobiles: A Review

Improve BOF Tapping Practice in AHMSA Mexico

Improved Blast Furnace Stove Operation With the Use of Oxygen Enriched Combustion Air

Improved Converter Process Control

Improved Determination of the Effect of Alloying Elements on the Peritectic Range in Low Alloyed Cast Steel

Improved Gear Spindle Longevity in a Cold Reduction Mill Operation

Improved Roll-Gap Lubrication to Reduce Energy Consumption and to Extend the Material Product Mix

Improvement in Sampling Process Precision by Means of an Inert Atmosphere Sampling System at ArcelorMittal Indiana Harbor East No. 2 Steel Producing

Improvement of Ladle Slidegates

Improving BF-BOF Performance and Safety Using Tenova’s Slop Detection System Technology

Improving Temperature Control at the RHOB

Improving the Ironmaking Process With Expert Systems in Closed-Loop Operation

In-Depth Analysis of Continuous Caster Machine Behavior During Casting With Different Roll Gap Taper Profiles

Incorporation of Charcoal in Coking Coal Blend - A Study of the Effects on Carbonization Conditions and Coke Quality

Increase Production in the EAfs in Ternium Guerrero, Mexico: Strategies and Actions

Increasing Energy Efficiency of the Electric Arc Furnace at Tenaris-Tamsa

Increasing Productivity and Rolling Quality Through Optimized Mill Window Geometry

Increasing Web Speed and Eliminating Tracking Problems in an Electro-Tinning Line with the PARALIGN Roll Alignment Report

Industrial Application of Chemical Energy for Special Steel Grades and Processes

Industrial Use of Pre-Oxidation During Continuous Hot-Dip Coating of (High) Alloyed Steels

Influence of Preliminary Metallization of Metallic Burden on Blast Furnace Process and Performance Parameters

Influence of Process Variables on Blast Furnace Operational Limits: Ternium Siderar Experience

Inhibition of Reoxidation of Direct Reduced Iron (DRI)

Innovation for Quality Assurance – Automatic Creation of QA Rules From Claims Data

Innovation in Automatic Billet Conditioning Using Advanced Optical Surface Crack Recognition System and High Pressure Grinding Machines

Interaction Between Gas and Liquid Phase in RH Vacuum Degasser

Investigation of HAGC System Performance With Various Circuitry Designs

Investigation of the Bath Flow in Q-BOP in Water Model Experiment

Investigation on Composition and Processing Parameters of Cu/P Bearing Corrosion Resistance Automobile Sheet

Kinetic Study of the Devitrification of Mold Powder Slags

Laboratory Evaluation of a New Method to Reduce Ridge Buckles in Cold Rolled Strip

Large-Diameter Slewing Ring Bearing Storage Methods: Comparisons and Cost Effectiveness

Laser Measurement System for the Refractory Lining of Hot Torpedo-Ladles

Latest Developments in Magnesia-Carbon Bricks

Latest Improvements to Increase Reliability and Productivity on Multi-Slitting Processes

Laying Head Upgrade

Lubrication of a Seamless Pipe Sizing Mill

MAG-QC - Tundish Metering Nozzle Quick Changer

Maintenance Strategy Implemented in the New ThyssenKrupp CSA Plant in Brazil

Material Handling: Focus on Safety with the Customization of Lifting Devices and Plant Wide Evaluations

Mathematical Model of Multiphase Flow in Argon Stirred Ladle and a New Technique for Prediction of the Mixing Time

Measures to Increase Efficiency and to Reduce CO2 Emissions in Iron and Steelmaking in Germany and Europe

Mechanical Condition Monitoring and Analysis Applications in the Steel Industry

Microstructure Simulator for Long Product Mills

Model of Gas Flow Through Upper Tundish Nozzle Refractory and Initial Bubble Size

Modern Approaches and CFD Modeling of Hot Process Building Air Induction Optimization

Modernization and Upgrade of a Static Var Compensator for an Electric Arc Furnace Application

Modernizations of the Beeckerwerth Hot Strip Mill for Manufacturing High Strength Grades With Special Requirements

Modification of the Microstructure in the Near-to-Surface Layer of Continuously Cast Billets of Low-Carbon Steel

MOREintelligence: An Innovative Multi-Dimensional Data Analysis System for Metallurgical Processes

MORGOIL Bearing Technology Upgrade at TERNIUM SIDERAR Hot Strip Mill

Multivariable Directions in the Improvement of Shape Actuator Performance

New Approach for Intelligent Motor Control Centers

New Concept of Ledge-Type Eddy Current Level Sensor and Practical Results at SSAB Tunnplat

New Concept of the Auxiliary Fuel Injection Tuyeres of Blast Furnaces Developed by Numerical Simulations

New Danieli Wide Plate Mill at Jiang Yin Xing Cheng Special Steel Works, P.R. of China

New Developments and Versatility of EcoStar Roller Enhancements

New Findings from the DMT Small-Scale Coking Test Retort Regarding Coke Quality and Coke Oven Wall Safety

New Generation in Preheating Technology for Electric Arc Furnace Steelmaking

New Magnesia-Alumina-Carbon Brick Technology for Steel Processing Vessels

New Philosophy and Strategies for HMI (Human-Machine Interface) Between the Operators and the Machines

New Roll Grinding Technologies for 20-High Cluster Mills

New Rolling Method of Reversing Cold Rolling Mill

New Standard Development for Blowing at the BOF Converter by Using Catch Carbon Practice

Nip Pressure Measurement System

Non-Oxidizing Reheating Rotary Hearth Furnace

Novel Application of Organic Rankine Cycle (ORC) Technology for Waste Heat Recovery From Reheat Furnace Evaporative Cooling System

Novel Modeling Concept for Vacuum Tank Degassing

Numerical Modeling of Flow Into Primary Dedusting System of a 130t Converter

On a New Slip-Stick Rolling Model With Non-Circular Roll Bite Containing Multiple Characteristic Zones

OneSteel Whyalla Blast Furnace Campaign Extension

Online Quality Prediction Based on Learning

Online Raft Control and High Top Pressure Control in Blast Furnace to Maximize Productivity

Operational Results of Latest Vacuum Plant Installations

Operational Results of PTI Slag Door System for EAF

Operational Results of the World’s Most Modern Bow Type Caster With Vertical Mold for the Production of 355-mm-Thick Slabs for Demanding Quality Requirements

Overcoming Mechanical Issues in Obtaining Stable Length and Speed Measurements in Steel Mills and Billet Caster Applications

OxyCup® Furnace Operation at TISCO, China

Oxygen Control and Its Effect on Steel Cleanliness During Electroslag Remelting of NAK80 Die Steel

Oxygen Steelmaking Furnace Alloy Model at United States Steel Corporation

Performance of Three to Five Poise Mold Powders With an Exothermic Addition

Phosphorus Equilibrium Between Liquid Iron and CaO-SiO2-MgO-FeO Slags

Pickling and Tandem Cold Rolling Technologies for Severstal North America in Dearborn, Michigan

Pickling Line / Tandem Cold Mill with Electrical and Automation Systems from SMS Siemag Successfully Commissioned at MMK

Pilot Testing of Fire Protection in Extremely Corrosive Industrial Duct Environments

Planning, Implementation and Commissioning of a Heavy-Duty 3-Roll Reducing and Sizing Block at Republic Steel, Lackawanna, N.Y.

Power Quality Compliance With SVC Plus

Practice of Process for Steelmaking of MnCr Gear Steel by 100t DC-LF-VD-CC Flow Sheet

Predicting the Performance of Carbon Steel EAF Dust Processing Technology - A Case History

Presentation of Innovative 250 / 350 mm Continuous Caster in Salzgitter

Productivity of 3 t/m3/day Over the Last Five Years at BF5 AHMSA Mexico

Project Management in the 21st Century Electronic Project Management

Protecting Bearings in Rolling Mills

Providing Secure Ground Protection for Electric Arc Furnaces During Inrush Conditions

Quenched and Tempered Bar

Radio-Frequency Sensor for Liquid Steel Level and Flux Powder Thickness Measurements in Continuous Casting Mould

Reaction Analysis of Continuous Desiliconization and Desulfurization in the Hot Metal Runner at Kobe No.3 Blast Furnace

Reaction Behavior of Ferro Coke and Its Evaluation in Blast Furnace

Real-Time Metallurgically Based Estimator of Microstructure and Tensile Properties of Hot Rolled Strips On-Line Coil Quality Estimator (CQE)

Recent Trends and Technologies in Ingot Casting

Recent Trends in Hot Dip Galvanizing of Advanced High Strength Steel at ThyssenKrupp Steel Europe

Reducing the Effect of Electrode Water Cooling on Electrical Stability in an Arc Furnace

Reliability Achievement Bronze Award: Caster Hydraulic Pusher Table Cylinder Upgrade

Reliability Achievement Gold Award: Gear Boxes See Double the Life by Replacing Conventional Recirculating Oil System

Reliability Achievement Silver Award: Improving Mill Performance Through Roll Shop Process Control

Reliability Achievements in the Steel Industries

Reliability of Casthouse Refractory System at No. 14 Blast Furnace, United States Steel Corporation

Remote Operational Monitoring and Control of Auxiliary Process Units and Electrical Systems

Research and Application of Magnesia-Based Retaining Block of Tundish Gas Curtain

Research on Newly Developed Martensitic Stainless Steel Plate Used in Hydropower Station

Results of Foaming Slag and Scrap Meltdown Control SIMELT CSM/FSM Based on Structure-Borne Sound in Electric Arc Furnace Operation

Review on Wiping: A Key Process Limiting CGL Productivity

Rod and Bar Mill Developments Over the Past Fifteen Years

Role of Slag Basicity on Thermodynamic Partitioning of Chromium and Manganese in Ferritic Stainless Melts

Roll Shop Auxiliaries and Complete Roll Shops

Rolling Quality Under Your Control! How 2 Million Coils Fit Into Your iPad

Safer Lock-Out Tag-Out with Permanent Electrical Safety Devices - Electrically Safe Work Conditions Based Upon NFPA 70E and OSHA

Safer Vibration Readings of Overhead Cranes in a Steel Manufacturing Environment

Selection of Ironmaking Technology for Existing Specific Conditions of European Part of Russian Federation

Siemens Vai’s WinLink® Technology

Simulated and Experimental Study of Segregation in Continuously-Cast High Carbon Bloom Steel

Sintering of Indian Iron Ores - Technical Considerations

Slag Entrainment Behavior in the Vacuum Chamber of RH Degasser

SOPRECO®: Single-Oven Pressure Control System Installed in the New Coke Oven Battery No. 3 at the Zentralkokerei Saar GMBH

Spray Cooling: Staying Cool in Hot Places

Start Up of the VSB Meltshop: The First Consteel®-EAF in Brazil

Starting a Tool to Improve Efficiency in Complex Secondary Steel Refining

State of the Art in the Treatment of EAF Dust

State-of-the-Art Automated Ultrasonic Material Testing Systems, Modularity And Practical Applications

State-of-the-Art PCI Technology for Blast Furnace ensured by Continuous Technological and Economical Improvement

Steel Expert Takes Command - Optimized Performance on BOF Converter

Steel Research - Then, Now and Tomorrow: The Brimacombe Lecture

Strengthening Mechanisms in Microalloyed Martensitic Plate Steels

Strip Lateral Control with Electromagnetic Steering Device

Study and Application of Cold Rolling Strip Walking Detection System

Study and Application on Forsterite Dry Vibration Material for Tundish

Successful Start-up and Benchmark Operating Results of 100 t FastArc® EAF at Kosco, Korea

Superior Profile Control Technology With Edge-Oriented Shifting

Supporting Environmental, Health and Safety Programs Through a Best-in-Class CMMS/EAM Solution

SVAI Gas Cleaning Options - A Solution for Every Problem

Synopsis of a Modern X-Ray Thickness Gauge

Taphole Clay for High Productivity Operation of Blast Furnace

Technical and Economic Evaluation of Slag Dry Granulation

Technological and Automation Upgrade for CSP® Plant TKSE Bruckhausen

Technological Apparatus for the Moderation of Meltshop Off-Gas

The 2.3 Mt/Y Most Modern Production Facilities in the Mediterranean Area for Flat Products at MMK Metalurji

The Case for the Eriez® CleanStream-tm Process

The Development and Technology of the AIST Process Benchmarker (APB)

The Effect of Hot Mill Processing Temperature Variations on Final Coil Properties of Hot Rolled Steels

The Effect of Silicon on Desulfurization of Al-Killed Steels

The Evolution of the Thin Slab Caster Concept: Latest TSC Technology to Produce Over 330 t/Hour per Strand

The Impact of Design and Operating Parameters on Skull Formation in a Blast Furnace Hearth

The Impact of Tapered Work Rolls in the Finishing Mill During Hot Rolling

The Increasing Importance of BOF Endpoint Control When Using Higher Phosphorous Containing Hot Metal

The Induction Heat Treatment Process and the Materials Performance of DIB STAM 1470

The Iron Ore Market 2012

The Longevity Technology on Refractory Linings of AOD Refining Furnace in Baosteel

The New BLT® High Performance Chute Transmission Gearbox Results of the First 18 months of Operation at Rogesa’s BF5

The New Frustum Canopy Hood for Steel Meltshops

The New Integrated Level 2 Melt Shop Management System at Latrobe Specialty Steels Company

The New ThyssenKrupp-Laser-Welding-Machine at HDGL No. 7

The Performance Culture-tm

The Production of Customer-Tailored ICDP Rolls by Using Alloying and Graphite Control Strategies

The Pulsative Electromagnetic Casting Technique for Slab Casting

The Rate Determining Step of the Oxidation of Natural Magnetite Concentrates

The Revolution in Heat Transfer Technology is Won, Forced Draft Burners Move Aside and the Thermal Kinetic Energizer Now Takes Center Stage

The Technology, Benefits and Measurement of the ELBY-tm Ladle Bottom

Thermal Load and Fatigue of Rolls in Hot Rolling

Thermal Stress Cracking of Sliding Gate Plates

Thermomechanical Processing for Quality Products in High Speed Rod Rolling Mills

Thermomechanical Simulation of Hot Rolled Q&P Sheet Steels

Transient Phenomena of Inclusions in Alloy Steels During RH-VD-CC Process

Transient Turbulent Flow Simulation with Water Model Validation and Application to Slide Gate Dithering

U. S. Steel Canada Lake Erie Works Stack Burner Project - Increase Stack Draft and Coke Production

Up-to-Date Cold Strip Production in Continuously and Discontinuously Operating Mills

Use of Dry Refractory Liners in Continuous Caster Tundishes: Characterization and Quality Aspects

Validation of the Numerical Model for Blast Furnace Shaft Process

Value In Use of the Dunite

Waste Heat Power Generation From EAFs, SAFs and Reheating Furnaces - A Comparison

Wood Pellets for Ironmaking From a Life Cycle Analysis Perspective