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By Mario Perez-Wilson


The process potential index, or Cp, measures a process's potential capability, which is defined as the allowable spread over the actual spread. The allowable spread is the difference between the upper specification limit and the lower specification limit. The actual spread is determined from the process data collected and is calculated by multiplying six times the standard deviation, s. The standard deviation quantifies a process's variability. As the standard deviation increases in a process, the Cp decreases in value. As the standard deviation decreases (i.e., as the process becomes less variable), the Cp increases in value.

By convention, when a process has a Cp value less than 1.0, it is considered potentially incapable of meeting specification requirements. Conversely, when a process Cp is greater than or equal to 1.0, the process has the potential of being capable.

Ideally, the Cp should be as high as possible. The higher the Cp, the lower the variability with respect to the specification limits. In a process qualified as a Six Sigma process (i.e., one that allows plus or minus six standard deviations within the specifications limits), the Cp is greater than or equal to 2.0.

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By John Klustner

 

With multiple personal-technology devices morphing into a single product, the telecommunications industry is experiencing a quantum leap in technical evolution. The comparatively primitive cell phone of just a few years ago must now be a music-playing, video-recording, web-browsing, photo-taking, and e-mailing personal accessory that you can still use to make a phone call. Why is it, then, given all this innovation, that when you have a question about your bill it takes so long for customer service to answer?

The processes and technology found in many call centers define their customer service, and unfortunately they haven’t kept pace with the quickly changing industry and its customers’ expectations.

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By Mike Richman

Cummins Inc. designs, manufactures, distributes, and services engines and related technologies, including fuel systems, controls, air handling, filtration, emission solutions, and electrical power generation systems. Cummins serves customers in more than 160 countries through its network of 550 company-owned and independent distributor facilities and more than 5,000 dealer locations. Cummins reported a net income of $739 million on sales of $13.05 billion in 2007.

 

Editor’s note: This is the second in a two-part series looking at how companies can share best practices such as Six Sigma across the supply chain. The first part of this series, which focused on heavy-duty truck manufacturer PACCAR, appeared in Quality Digest’s October 2008 issue. You can view that article online at www.qualitydigest.com/magazine/2008/oct/article/partnering-change-part-1.html.

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By Quality Digest

 

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Welcome to Quality Digest’s 2008 Calibration Software and Services Directory

On the following pages you’ll find nearly 200 companies that can help you properly calibrate your measurement equipment. Included in each listing is the company name, address, telephone and fax numbers, web address, and a key showing whether the company in question provides calibration software (SW), services (SVC), or both. Further information, including detailed descriptions of these companies’ products and/or services, can be found online at www.qualitydigest.com/content/buyers-guides.

Quality Digest hasn’t evaluated, nor do we endorse, any of the following calibration software and/or service providers. This directory is intended to be used as a guide; please contact the companies themselves for further information.

Good luck in your search for the right calibration software and/or services provider.

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By Charles Wells

Most in the electronic manufacturing services industry are acutely aware of the growing problem of counterfeit and substandard electronic components within the supply chain, as well as the headaches that they cause.

Although industry and governments are working diligently in addressing counterfeit abatement, you may already have one of the most useful tools in combating phony parts in place right on your production floor.

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By Nicolette Dalpino

 

What is quality? An academic definition of quality as it relates to business might be that quality is a product or service that consistently has zero defects, conforms to particular specifications, and is satisfactorily received by the customer. Another aspect of quality is that it is a thought process sought out by organizations to create an overall drive toward efficiency, the reduction of waste, and the continual creation of more streamlined management processes.

“Unlike twenty years ago, when the quality department was viewed as the creator of quality, now the whole concept is more ingrained into the culture of organizations,” says Ron Atkinson, past president of the American Society for Quality. “Quality is created by the people performing the function, whether it be assembling a Bluetooth device or filling out an intake form at a medical clinic. Therefore, a culture of quality is emerging in which the leadership of organizations is emphasizing that the functional areas are responsible for quality in the same way that they are responsible for manpower costs, etc.”

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By Tom Pyzdek


In 1988, Motorola Corp. became one of the first companies to receive the Malcolm Baldrige National Quality Award. The award strives to identify those  excellent firms that are worthy role models for other businesses. One of Motorola's innovations that attracted a great deal of attention was its Six Sigma program. Six Sigma is, basically, a process quality goal. As such, it falls into the category of a process capability (Cp) technique.

The traditional quality paradigm defined a process as capable if the process's natural spread, plus and minus three sigma, was less than the engineering tolerance. Under the assumption of normality, this translates to a process yield of 99.73 percent. A later refinement considered the process location as well as its spread (Cpk) and tightened the minimum acceptable so that the process was at least four sigma from the nearest engineering requirement. Motorola's Six Sigma asks that processes operate such that the nearest engineering requirement is at least plus or minus six sigma from the process mean.

Motorola's Six Sigma program also applies to attribute data. This is accomplished by converting the Six Sigma requirement to equivalent conformance levels (see Figure 1).

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By Nick Van Weerdenburg

Quality improvement has stalled in manufacturing due to an inability to capture, continuously improve, and leverage performance knowledge in design and manufacturing activities. Other enterprise systems, such as project life-cycle management (PLM), fail to improve quality because they treat it as a process management problem. The fundamental challenges to achieving quality are knowledge-management and continuous-improvement issues. Recently, quality life-cycle management has received a boost from enterprise software solutions designed to change how manufacturers go about designing quality into their manufacturing processes and products.

Some statistics reported by manufacturers highlight the current dilemma in quality performance:

Eighty percent of all quality issues are repeat issues. These are errors that have happened before and were fixed, yet the lesson learned wasn’t recalled by or communicated to another group so that preventive action could be taken.

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By Aaron E. Pietras

Qing Rong Zhang (behind computer, center), a Shanghi-based quality engineer with more than 30 years of experience with automotive original equipment manufacturers and tier-one suppliers, handles an overall supplier assessment.

 

It’s hard not to pick up a newspaper or industry magazine or surf the internet without reading that manufacturing industries are relocating their operations to other countries. During the past couple of years, it’s been equally difficult to avoid articles concerning serious quality issues present in consumer and industrial products produced in emerging economies. Even as product lines move to China, India, and Russia, domestic companies are losing significant numbers of experienced employees throughout their organizations due to early retirement or reassignment. Diminished and often lost in this regard is the tribal knowledge of operators who know the pulse of the manufacturing process. This triple whammy of outsourcing, loss of tribal knowledge, and decrease in product quality has emphasized the need for third-party suppliers of supply chain solutions.

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By Quality Digest

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Welcome to Quality Digest’s 2008 State Quality Awards directory. On the following pages you’ll find a state-by-state summary of available awards, contact information and award summaries, including who may apply and deadline dates. We’ve done our best to include only the information that we’ve personally confirmed, but we nevertheless recommend that you contact award administrators directly to verify important dates, requirements and other critical data.

We wish you the best of luck on your journey to quality award recognition.