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A high-level test generation algorithm SWIFT is proposed which incorporates a symbolic scheduling procedure. derived jiom high-level synthesis applications. to resolve decision conflicts during test generation. SWIFT uses the induced. fault model to generate, functional tests that guarantee detection of low-level structural faults. When applied to ,fiinctional models of representative 74X-series, ISCAS-85 und ISCAS-89 circuits, SWIFTproduces test sequences that cover all gate-level stuck-at^ faults. Surprisingly, although they are derived from a high-level functional description of the circuit under test, most of these test sequences are ofprovahly minimal or near-minimal size.

A new type of jacket design was developed for Shell Offshore Inc.'s Enchilada platform located in the Gulf of Mexico in 630 feet of water. The design was developed by an integrated team representing the operator and contractors and was based on utilizing specific contractor equipment and procedures in order to lower costs and reduce cycle time. The jacket was designed for installation in two sections that were joined underwater with a grouted connection. Both jacket sections were lifted from transport barges and installed on location with HeereMac's SSCV Balder. The installation method avoided the typical launch framing required for jackets in this water depth. Launch framing accounts for as much as 25% of a typical launched jacket weight. This paper describes the unique features and important aspects of the project, including contracting, design approach, fabrication, and installation. The development of this platform concept has added an alternative to conventional single piece launched jacket designs for water depths in the 500 to 700 foot range. Results are presented showing the steel weight savings and the schedule reduction enabled by the design. Information provided in this paper will allow designers and planners to evaluate this alternative design concept. Introduction The Enchilada platform was designed as a fixed structure in 630 feet of water in the Gulf of Mexico. The overall field development strategy in Garden Banks Blocks 128 and 172 is described in Reference 1. The primary challenges of the platform design and construction were to reduce costs and lower design to construction cycle time. The design practice for fixed offshore structures is well established. In recent years, designs have steadily produced significant cost and schedule improvements. The challenge of producing further improvements on the established fixed platform design practice requires innovation, risk taking, and new design approaches. During predesign studies for the Enchilada development, a novel design approach and design concept were identified by a team consisting of engineers from Shell, Aker Omega, Aker Gulf Marine and Heere Mac. The design approach utilized an integrated design team to develop a new type of design taking advantage of existing contractor equipment and procedures. The design concept included a two-piece lifted jacket that was joined underwater with a grouted connection. Platform Functional Requirements The Enchilada platform was designed for topside facilities capable of processing 60,000 barrels of oil per day and 400 million cubic feet of gas per day. The total topside operating weight is approximately 9,000 tons with an initial dry lift weight of 4,000 tons. The platform will support 15 production wells and 17 import/export pipeline risers. The export pipelines will be capable of transporting over 1 billion cubic feet of gas per day and 250,000 barrels of oil per day (some of the pipelines import production from nearby fields). Predesign Studies Preliminary design activities were initiated in November of 1994. With substantial contractor involvement, preliminary designs were developed for both a single piece launched jacket and for the two-piece design that was ultimately chosen. In addition to the preliminary structural design, cost and schedule estimates were developed. At the same time, a preliminary design was developed for the deck and facility.

We present novel test set encoding and pattern decompression methods for core-based systems. These are based on the use of twisted-ring counters and offer a number of important advantages–significant test compression (over 10X in many cases), less tester memory and reduced testing time, the ability to use a slow tester without compromising test quality or testing time, and no performance degradation for the core under test. Surprisingly, the encoded test sets obtained from partially-specified test sets (test cubes) are often smaller than the compacted test sets generated by automatic test pattern generation programs. Moreover, a large number of patterns are applied test-per-clock to cores, thereby increasing the likelihood of detecting non-modeled faults. Experimental results for the ISCAS benchmark circuits demonstrate that the proposed test architecture offers an attractive solution to the problem of achieving high test quality and low testing time with relatively slower, less expensive testers.

The Enchilada platform was designed as a central Hub for numerous pipelines in the Garden Banks area of the Gulf of Mexico. A new approach was developed to bring these pipelines up to the platform deck. The Enchilada platform was designed for 17 pipeline connections and as many as 23 pipelines were considered during the design. This large number of pipelines required either a new approach for the pipeline connections or the use of a jacket structure with more main legs. The four main legs of the Enchilada jacket did not have sufficient space for conventional individual or bundled pulltubes. The approach developed for Enchilada was to bring all pipelines up to the deck within the conductor guide framing through vertical pipeline bundles nicknamed CONSPUB's (Conductor Supported Pulltube Bundle). The CONSPUB's are vertically supported near the base of the jacket and require only lateral support at each guide elevation. The vertical portions of the CONSPUB's are field installed, which defers costs for future pipelines. This paper describes the designdetails used for the Enchilada design and discusses alterative details that may also be used. Benefits of this approach are discussed including cost savings and future pipeline flexibility, The CONSPUB approach described in the paper will provide designers with an alternative to conventional leg supported pulltubes and risers. Introduction The overall field development strategy in Garden Sanks Blocks 128 and 172 is described in Reference I. The Enchilada platform was designed as part of this field development and was planned as a central Hub for numerous pipelines. Prior to the decision to design the Enchilada structure as a Hub, the Enchilada platform was planned as a minimal stand-alone facility for drilling and production. The original jacket design concept consisted of a four-leg jacket to be installed in two lifted pieces and joined in-place offshore. The two-piece lifted jacket concept offered significant cost and schedule advantages2 and it was preferred to utilize the same concept even with the higher functional requirements of a hub, specifically a large number of pipelines. The final platform was designed for 17 pipeline connections and as many as 23 pipelines were considered during the early design. Conventional pulltubes are supported along the main legs of the jacket. Incorporating 17 pulltubes would have caused significant congestion of the four main legs of the planned Enchilada jacket. The design team concluded that the four-leg jacket structure did not have sufficient space for conventional individual or bundled pulltubes. A new approach was developed to bring these pipelines up to the platform deck. This approach was to bring all pipelines up to the deck within the conductor guide framing through vertical pipeline bundles nicknamed CONSPUB's (Conductor Supported Pulltube Bundle). The vertical portions of the CONSPUB's can be field installed, which defers costs and eliminates lift weights of the future pipelines. The deferred weight was an important factor for the Enchilada jacket, since the lift weight of the jacket sections were near the capacity of the offshore construction vessel cranes. Deferring costs improves the profitability of the project and avoids pre-installing components that may never be used.