An ERD (Entity Relationship Diagram) is a graphical representation of the data in rest within a system (e.g. a business, an organization, an application) that is subject to analysis.
1. REFERENCE DOSE (RfD): DESCRIPTION AND USE IN HEALTH RISK ASSESSMENTS. 1.1. INTRODUCTION. This concept paper describes the U.S. Environmental Protection Agency's (U.S. EPA) principal approach to and rationale for assessing risk for health effects other than cancer and gene mutations from chronic chemical exposure.
The rear flank downdraft (RFD) is a downward rush of air on the back side of the storm that descends along with the tornado. The RFD looks like a âclear slotâ or âbright slotâ just to the rear (southwest) of the wall cloud.