David Oppong - Academia.edu (original) (raw)

Papers by David Oppong

TEXILA INTERNATIONAL JOURNAL OF MANAGEMENT

For most existing computer systems, once the user’s identity is verified at login, the system res... more For most existing computer systems, once the user’s identity is verified at login, the system resources are available to that user until he/she exits the system. In high-risk environments such as healthcare or where the cost of unauthorized use of a computer is high, a dynamic check of the user’s identity is extremely important. This study evaluated the feasibility of multifactor authentication with biometrics, incorporating both traditional and the time dynamics-based techniques of keystrokes (behavioural) and fingerprint swipes (user’s physical characteristics), for adoption into an eHealth system (DHIMS 2). The results indicate that individual authentication by Keystroke and Fingerprint dynamics yields acceptable results. However, when combined with the traditional methods of authentication, extremely high security is obtained than could be obtained by each paradigm acting independently. Hence, it is concluded that combining Keystroke and fingerprint dynamics with traditional authentication procedures into an eHealth system (DHIMS 2) will yield a system with improved account security and integrity of health information.

Journal of Food Protection, 1988

A comparison was made between the acridine orange stain, gram stain and methylene blue stain for ... more A comparison was made between the acridine orange stain, gram stain and methylene blue stain for direct microscopic counts (DMC) of microorganisms in gravy mixes, spices, cocoa products and baby foods. Bacteria were detected in 96% (45/47) of the samples stained with acridine orange, 64% (30/47) for the gram stain and 66% (31/47) for the methylene blue stain. In most instances, acridine-orange smears showed higher numbers of bacteria than the traditional stains. The staining quality of the acridine orange was better than the conventional stains with bacteria, yeast cells, and mold hyphae fluorescing very differently from the background. The results indicate that direct staining with acridine orange is better than the traditional methods for estimating bacterial numbers in such foods.

TEXILA INTERNATIONAL JOURNAL OF MANAGEMENT

For most existing computer systems, once the user’s identity is verified at login, the system res... more For most existing computer systems, once the user’s identity is verified at login, the system resources are available to that user until he/she exits the system. In high-risk environments such as healthcare or where the cost of unauthorized use of a computer is high, a dynamic check of the user’s identity is extremely important. This study evaluated the feasibility of multifactor authentication with biometrics, incorporating both traditional and the time dynamics-based techniques of keystrokes (behavioural) and fingerprint swipes (user’s physical characteristics), for adoption into an eHealth system (DHIMS 2). The results indicate that individual authentication by Keystroke and Fingerprint dynamics yields acceptable results. However, when combined with the traditional methods of authentication, extremely high security is obtained than could be obtained by each paradigm acting independently. Hence, it is concluded that combining Keystroke and fingerprint dynamics with traditional authentication procedures into an eHealth system (DHIMS 2) will yield a system with improved account security and integrity of health information.

Journal of Food Protection, 1988

A comparison was made between the acridine orange stain, gram stain and methylene blue stain for ... more A comparison was made between the acridine orange stain, gram stain and methylene blue stain for direct microscopic counts (DMC) of microorganisms in gravy mixes, spices, cocoa products and baby foods. Bacteria were detected in 96% (45/47) of the samples stained with acridine orange, 64% (30/47) for the gram stain and 66% (31/47) for the methylene blue stain. In most instances, acridine-orange smears showed higher numbers of bacteria than the traditional stains. The staining quality of the acridine orange was better than the conventional stains with bacteria, yeast cells, and mold hyphae fluorescing very differently from the background. The results indicate that direct staining with acridine orange is better than the traditional methods for estimating bacterial numbers in such foods.