• Home
• Academic
  • Academic Overview
  • Undergraduate
  • Graduate
• Research
• Extension
  • Extension @ BAE
  • Program Areas
  • Extension Mission
  • Publications
  • Workshops
  • Action Photos
  • Extension Personnel
• Training & Credit
  • Overview
  • Distance Education
  • Workshops & Conferences
  • Graduate Credit Programs
  • Professional Development
• Community
  • Business Connections
  • Public Relations & Media
  • Scholarship & Giving
  • Youth Resources
  • Topics of Public Interest
  • Alumni
  • Faculty Positions
  • About Bio & Ag
  • NEWS
• Directory / Contacts

W. F. McClure, Ph.D., P. E.

Professor Emeritus of Biological and Agricultural Engineering

Bioinstrumentation, NIR spectrometry,
physiochemical properties, robotics

Retired: July 2006

Biographical Sketch

McClure's expertise is in bioinstrumentation, computer control systems and physiochemical properties of biomaterials. Research to develop methods for measuring quality/composition of agricultural products has resulted in several significant contributions: In cooperation with Dr. Richard Gwynn of the Oxford Tobacco Research Station, McClure (1969) designed a two filter photometer which was used to study chlorophyll degradation during this curing. This instrument was used to establish the fact that chlorophyll degradation is an inherited trait and that the chlorophyll oxidation process is a first order reaction. Dr. Gwynn later used this instrument to select germ plasm based on the chlorophyll degradation constant. This led to the development of a hand-held meter for nondestructive field determinations of chlorophyll in tobacco leaves.

McClure was one of the first in the nation, and the first on the NCSU Campus, to recognize the potential of fiber optics for remotely monitoring optical properties of biological products. In 1972 he designed a fiber optic system for remotely monitoring degradation of chlorophyll in plant tissue during processing. He later developed a control system based on this sensor.

Again using fiber optics, McClure demonstrated that the optical properties of blueberries and grapes could be accurately measured with fiber optic technology. Working with Drs. Rohrbach, Ballinger and Kushman, McClure designed a laboratory berry sorter, called the Berrymatic, which increased the sorting rate from 2 fruit per minute to 64 fruit per minute. This machine was used for several years by cooperators in the Departments of Horticultural Science to establish ripening characteristics of blueberries and grapes, storage characteristics of blueberries and certain quality indices of blueberries and grapes. The Berrymatic was also used by cooperating researchers in the Department of Food Science to study the effect of ripeness of grapes on wine quality.

Basic work with the Berrymatic led to the cooperative development with (Dr. R. P. Rohrbach) of the M-Belt Sorter, a high volume sorting machine which was designed to separate blueberries and grapes into three categories of ripeness at a rate of 600 pints/hour. A patent was granted to McClure and Rohrbach for the design of this machine. McClure received support in the late 70s to study ways to automatically separate aflatoxin contaminated pistachio nuts bearing the suspect bright-greenish-yellow (BGY) fluorescence. Fiber optic technology was again used to develop this instrument which had a 94% accuracy for removing the BGY nuts.

McClure developed a filter photometer for the Food Science Department (Dr. Ken Swartzel) for studying the effect of ultra high temperature treatments on the optical properties of milk. This instrument was used to determine heat regimes which altered the basic color of milk.

McClure cooperated with his fellow researchers (Dr. D. Willits and team) in the design of a computer based greenhouse control systems. Cooperating with USDA engineers, McClure designed the circuitry for a densitometer which is still used today for measuring absorption of thin layer chromatograms. These chromatograms are used to measure aflatoxin contamination in peanuts.

His most outstanding contribution to basic knowledge has been his work on the development of NIR technology for rapidly measuring the quality and chemical composition. His foresight and planning in the early 70's brought about the design of the COMP/SPEC, the first minicomputer based near infrared spectrophotometer on the NCSU Campus. His close cooperation with USDA researchers (especially the late Dr. R. E. Williamson) led to the construction of the second COMP/SPEC which is used today for selecting germ plasm related to chemical composition. The system reduces costs of chemical analyses from more $35.00 for the required analyses to less than $1.00. Directly as a result of his efforts, today NIR technology finds widespread application throughout the tobacco manufacturing industry. McClure is an active consultant to both manufacturers of NIR equipment and users in the food and tobacco industries. He has been and continues to be instrumental in the selection of design parameters, both hardware and software, for many of the commercial NIR instruments available today.

In the late 70's McClure efforts to improve the efficiency and effectiveness of NIR instruments led him to Fourier analysis. He was the first to demonstrate that chemical constituents in samples of agricultural products could be estimated from the first 12 Fourier coefficients derived from NIR spectra of the samples. His work was published in Volume 38(3) of Applied Spectroscopy. Among the advantages of this approach was the reduction of the need for computer storage by 96% and a reduction of computer time required to calibrate an NIR instrument by 98%. Furthermore, his work points to the use of an NIR interferometer for obtaining the Fourier coefficients more directly, an instrument which could decrease the costs of NIR instruments and provide more rugged systems for on-line analysis. McClure's work drew national attention when Dr. Tomas Hirschfeld, Lawrence Livermore Laboratory, said, "From Dr. McClure we've heard of successful applications of NIRA technology (near-infrared correlation transform spectroscopy) using the first few samples of an interferogram to drive the learning algorithm and calibration procedures. The man actually gets good analytical procedures using only data corresponding to spectral information wider than 400 cm-1. (Applied Spectroscopy 40(1):121-122)." On November 13, 1991 McClure received the Eastern Analytical Symposium Award for Outstanding Achievements in Near Infrared Spectroscopy.

McClure, along with his graduate students, has begun to probe computer controls technology in the development of computer-vision and robotics. With a gift of a Series III Computer System they have developed AGVISION, a computer base vision system for studying images of agricultural products. Developments of grippers with tactile feedback is a parallel effort. Blending of computer vision, pattern recognition algorithms, gripper development and robotics, McClure is currently conducting research to provide economical, intelligent, robotics based systems for agricultural applications.

McClure is author of more than 80 refereed publications, holds three patents, and is the author of chapters in two books. Three of his publications were published jointly with Japanese colleagues and he has cooperatively published in Australia, England and Germany. He has applied for and received numerous research grants totaling more than half a million dollars during his career with North Carolina State University.

In the 1979 Research-Extension review McClure was evaluated as follows: McClure's research "program has national recognition for both personnel and facilities which are among the best found in any institution . . . "Dr. McClure has made significant contributions toward the application of electronics including microprocessors in agriculture . . . . "Effective cooperative programs exists between USDA and station personnel in the area of quality evaluation. Cooperation from faculty within the department and from other units, especially the station statisticians, was evident and contributed measurably to the project."