History of Six Sigma

Six Sigma was originally developed as a set of practices designed to improve manufacturing processes and eliminate defects, but its application was subsequently extended to other types of business processes as well. In Six Sigma, a defect is defined as anything that could lead to customer dissatisfaction.

The particulars of the methodology were first formulated by Bill Smith at Motorola in 1986. Six Sigma was heavily inspired by six preceding decades of quality improvement methodologies such as quality control, TQM, and Zero Defects, based on the work of pioneers such as Shewhart, Deming, Juran, Ishikawa, Taguchi and others.

Like its predecessors, Six Sigma asserts that –

• Continuous efforts to achieve stable and predictable process results (i.e. reduce process variation) are of vital importance to business success.
• Manufacturing and business processes have characteristics that can be measured, analyzed, improved and controlled.
• Achieving sustained quality improvement requires commitment from the entire organization, particularly from top-level management.

Features that set Six Sigma apart from previous quality improvement initiatives include –

• A clear focus on achieving measurable and quantifiable financial returns from any Six Sigma project.
• An increased emphasis on strong and passionate management leadership and support.
• A special infrastructure of “Champions,” “Master Black Belts,” “Black Belts,” etc. to lead and implement the Six Sigma approach.
• A clear commitment to making decisions on the basis of verifiable data, rather than assumptions and guesswork.

The term “Six Sigma” is derived from a field of statistics known as process capability studies. Originally, it referred to the ability of manufacturing processes to produce a very high proportion of output within specification. Processes that operate with “six sigma quality” over the short term are assumed to produce long-term defect levels below 3.4 defects per million opportunities (DPMO). Six Sigma’s implicit goal is to improve all processes to that level of quality or better.

Six Sigma is a registered service mark and trademark of Motorola, Inc.^[8] Motorola has reported over US$17 billion in savings from Six Sigma as of 2006.

Other early adopters of Six Sigma who achieved well-publicized success include Honeywell (previously known as AlliedSignal) and General Electric, where the method was introduced by Jack Welch. By the late 1990s, about two-thirds of the Fortune 500 organizations had begun Six Sigma initiatives with the aim of reducing costs and improving quality.

In recent years, Six Sigma has sometimes been combined with lean manufacturing to yield a methodology named Lean Six Sigma.

Economical waterproofing solution for Roofing

Economical waterproofing solution is a combination of a Liquid Applied bituminous Membrane (Sikaproof Membrane) with a cementitious mortar (Sikalatex Mortar) as protective layer for the roof.

    * Apply Sikaproof Membrane bitumen polymer modified waterproofing liquid membrane

    * Apply cementitious Sika Latex TH waterproofing slurry & mortar screed

    * Seal joints with high capacity movement Sikaflex Construction

    * Apply curing compound to protect the substrate from plastic shrinkage cracking

Sikaproof Membrane: Highly elastic, water based bitumen emulsion coating used waterproofing for concrete slab.

Sika Latex TH: A synthetic rubber emulsion used as a cement mortar admixture where good adhesion and water resistance is required.
Surface Preparation

    * All weak and unsound concrete must be removed by mechanical tool and repair when it’s necessary.

    * The concrete must be clean and free from dust, oil, or any laitance or loose materials and must be dry prior to the application of the Sikaproof Membrane waterproofing layer.

    * The existing concrete roof slab to which the waterproofing layer is to be applied should have strength of > 20 Mpa.

Application

    * Apply the first coat of Sikaproof Membrane (diluted with 50% water) onto the dry concrete substrate by using brush or spraying. The rate of application should be 0.3 kg/m2/coat.

    * Allow the first coat of Sikaproof Membrane completely dry prior (after 2 h) to the application of second coating (without diluted), with consumption 0.85 kg/m2/coat.

    * Allow the second coat of Sikaproof Membrane completely dry prior (after 3 h) to the application of third coating (without diluted), with consumption 0.85 kg/m2/coat.

    * The Sika Latex  bonding should be applied to the third coat of Sikaproof Membrane after approx. 4 hours.

    * Mix 1  liter Sika Latex + 1  liter of water + 4 kg cement by weight. Consumption 0.25 ltr Sika Latex/m2 .

    * Apply the Sika Latex mortar when the Sika Latex bonding slurry is still wet. Mix 1 liter Sika Latex and 1 liter water. Consumption 1 liter Sika Latex/m2/20mm thickness with a cement / sand ratio of 1:3 by weight.

    * The preferred finish to the Sika Latex  waterproofing mortar is by steel trowel and curing.

    * Cutting expansion joint for mortar layer.

Construction Surveying Job

Where there is a construction site, there are construction surveyors. Before any construction project can start, the site area must be surveyed. The drawings created by the engineering team must be oriented to the actual lie of the land. Measurements of the building site are taken using surveying equipment, which are then compared to the set of master blueprints. These initial measurements will serve as the basis for all events that take place throughout the construction process.

Prior to the electronic age, surveyors used something called a transit to help mark locations and perform other surveying-type tasks, such as defining angles. The total station is the modern update of that vital tool, and it is the prime piece of equipment in any construction surveyor’s bag of tricks. Sitting on a tripod, the total station uses trigonometry, triangulation, and coordinates (x-y-z in a three-dimensional plane) to measure angles and distances in the field. Points are marked and noted in the total station’s software, and all data can be downloaded to any number of computing-type devices in order to create a map, modify an existing map, or simply confirm that map data are correct. These days, GPS data are also incorporated into the total station’s computing ability. In outdoor locations where sky visibility is adequate-urban canyons or heavy tree canopy conditions can be problematic-it is not unusual for a construction surveyor to achieve sub-centimeter accuracy.

Highway Construction Surveying
The placement and construction of highways is one area where the involvement of a construction surveyor is especially valuable. First, the existing terrain is surveyed. Areas are noted where dirt must be excavated, especially to what level and grade. Once the material is moved, the surveyor will double-check that everything matches the plans. One goal is to reduce the distance excavated material travels, so engineers take the surveyor’s computations and create something called a “mass diagram” to figure out optimal relocation sites. In other words, they will take dirt from Spot A that requires reduction and move it to Spot B that requires build-up. In the old days, wooden stakes were driven into the ground to mark road edges in the highway alignment stage, but the accuracy and widespread usage of GPS has eliminated this laborious process.

Building Construction Surveying
A construction surveyor controls the location of everything from foundation lines to footings to ancillary items such as sidewalks and driveways. Using a total station and observed GPS data in a manner similar to highway construction, every spot and corner is noted in the field and then compared to the master plan. One specialized job for the construction engineer is to ascertain the proper placement of anchor bolts on structural steel and pre-cast concrete. Because of the nature of the item-these bolts, after all, are responsible for holding the building components together-the exact placement of each bolt is critical to structural integrity. Since there is such a wide variety of design in buildings, anchor bolts can be placed anywhere within or without the building’s footprint. They may not fall in a straight line, so a construction surveyor must be ever vigilant to follow exactly the architectural and engineering plans when marking anchor bolt locations on individual structural components.