Both spring‐summer and fall‐winter sand transport have been observed on the Long Island, New York, inner shelf at water depths of 20‐22 m using a radio‐isotope sand tracer system. The extent of dispersal of the tagged, fine sand was measured at 3 week intervals in two 70 day experiments. In the late spring and early summer, movement was primarily diffusive in nature, extending 100 m around the line of tracer injection, while late fall‐winter patterns had strong advective features, including an ellipsoidal outline extending approximately 1500 m westward of the injection points after the passage of several storms with strong northeasterly winds. Near‐bottom current observations made with Savonius rotor sensors identify the event responsible for the bulk of the transport over the 135 day observation period as a storm flow of 2 days duration. Tracer and current observations together suggest that westward winter storm flow along the Long Island shelf is the major mechanism of sand transport at these depths on a yearly time scale. A least‐squares fit of several of the observed winter patterns with a plume model yields average sediment mass flux lower bounds of 3.2 × 10−3 gm/cm/sec and 1.7 × 10−1 gm/cm/sec for ‘typical’ and extreme winter storm activity.

We have observed late fall and winter bedload sediment transport and the overlying current field in ridge and swale topography on the inner continental shelf south of Long Island, and can report movement of bed material at a water depth of 20 m to a distance of approximately 1500 m after several storm events. Movement over an 11‐week observation period was longshore and oblique to the ridge crest at the experimental site. Currents were also predominately longshore, but long term averages demonstrate that a vertical shear existed in the fluid motion. Although the number of sediment transport "events" suggested by the current meter data is nearly balanced in eastward and westward directions, both estimates of transport from current speeds and sand tracer dispersion patterns show that several westward flowing events dominated the transport during a two and one‐half month period. A quantitative upper bound of 31 cm/sec on the threshold velocity for sediment movement in this size range is also set by the data.

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Application-specific integrated circuits (ASICs), which have traditionally been cost-effective only for high volume applications, can now be designed using high quality, inexpensive tools and can be fabricated in small quantities using MOSIS (Metal Oxide Semiconductor Implementation Service). Numerous computer-aided design tools developed under government sponsorship are available to organizations within the United States for just a media handling fee (typically about $200 each). The tool integration and enhancement activities described in this paper have resulted in a proven set of high quality aids that permit the design of custom and semicustom analog and digital ASICs. Examples of projects implemented using this tool set are given along with the support activities that are being conducted to transfer this technology to other federal agencies and universities.

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