Quality Control

Quality control is a process employed to ensure a certain level of Quality in a product or service. It may include whatever actions a business deems necessary to provide for the control and verification of certain characteristics of a product or service. The basic goal of Quality control is to ensure that the products, services, or processes provided meet specific requirements and are dependable, satisfactory, and fiscally sound.

Essentially, quality control involves the examination of a product, service, or process for certain minimum levels of Quality. The goal of a Quality control team is to identify products or services that do not meet a company's specified standards of Quality. If a problem is identified, the job of a Quality control team or professional may involve stopping production temporarily. Depending on the particular service or product, as well as the type of problem identified, production or implementation may not cease entirely.

Usually, it is not the job of a Quality control team or professional to correct Quality issues. Typically, other individuals are involved in the process of discovering the cause of Quality issues and fixing them. Once such problems are overcome, the product, service, or process continues production or implementation as usual.

Quality control can cover not just products, services, and processes, but also people. Employees are an important part of any company. If a company has employees that don't have adequate skills or training, have trouble understanding directions, or are misinformed, Quality may be severely diminished. When Quality control is considered in terms of human beings, it concerns correctable issues. However, it should not be confused with human resource issues.

Experimental Design

Scientific experiments are of essential importance in people's surviving and exploring of nature. Experiments are performed almost everywhere, usually for the purpose of discovering something about a particular process and for the development of a new process. It is usually expected that the experiment could result in increase of the yield, improvement in the quality, reduction of the development time or reduction of the overall costs.

When the experimenter wants to investigate more factors (for instances, more than 4 factors) in an experiment one cannot expect to obtain a good result without the use of modern experimental designs. For example, suppose that the experimenter wants to consider various reacting temperature, time, pressure, speed and several materials in an experiment. Choose five testing levels for each of the factors. The total of level-combinations is 55=3125, that is too many in the sense of experimental expense and time. How can we use a small number of experiments to explore relationships between the response (output) and the factors (inputs)? We need some efficient fractional factorial designs. If we use the so-called orthogonal design, the number of experiments can be reduced to 25.

The Uniform design is another such efficient fractional factorial design. It was proposed by Professor Fang Kai-Tai and Professor Wang Yuan in 1980. It has been successfully used in various fields such as chemistry and chemical engineering, pharmaceutics, quality engineering, system engineering, survey design, computer sciences and natural sciences. The uniform design has been recognized as an important space-filling design by the international community. The space-filling design has played an important role in large system engineering. The uniform design is also one of the robust designs.