Reducing Library Characterization Time for Cell-aware Test while Maintaining Test Quality

Cell-aware test (CAT) explicitly targets faults caused by defects inside library cells to improve test quality, compared with conventional automatic test pattern generation (ATPG) approaches, which target faults only at the boundaries of library cells. The CAT methodology consists of two stages. Stage 1, based on dedicated analog simulation, library characterization per cell identifies which cell-level test pattern detects which cell-internal defect; this detection information is encoded in a defect detection matrix (DDM). In Stage 2, with the DDMs as inputs, cell-aware ATPG generates chip-level test patterns per circuit design that is build up of interconnected instances of library cells. This paper focuses on Stage 1, library characterization, as both test quality and cost are determined by the set of cell-internal defects identified and simulated in the CAT tool flow. With the aim to achieve the best test quality, we first propose an approach to identify a comprehensive set, referred to as full set, of potential open- and short-defect locations based on cell layout. However, the full set of defects can be large even for a single cell, making the time cost of the defect simulation in Stage 1 unaffordable. Subsequently, to reduce the simulation time, we collapse the full set to a compact set of defects which serves as input of the defect simulation. The full set is stored for the diagnosis and failure analysis. With inspecting the simulation results, we propose a method to verify the test quality based on the compact set of defects and, if necessary, to compensate the test quality to the same level as that based on the full set of defects. For 351 combinational library cells in Cadence’s GPDK045 45nm library, we simulate only 5.4% defects from the full set to achieve the same test quality based on the full set of defects. In total, the simulation time, via linear extrapolation per cell, would be reduced by 96.4% compared with the time based on the full set of defects.

Experimental realization of phase-controlled dynamics with hybrid digital–analog approach

Quantum simulation can be implemented in pure digital or analog ways, each with their pros and cons. By taking advantage of the universality of a digital route and the efficiency of analog simulation, hybrid digital–analog approaches can enrich the possibilities for quantum simulation. We use a hybrid approach to experimentally perform a quantum simulation of phase-controlled dynamics resulting from a closed-contour interaction (CCI) within certain multi-level systems in superconducting quantum circuits. Due to symmetry constraints, such systems cannot host an inherent CCI. Nevertheless, by assembling analog modules corresponding to their natural evolutions and specially designed digital modules constructed from standard quantum logic gates, we can bypass such constraints and realize an effective CCI in these systems. Based on this realization, we demonstrate a variety of related and interesting phenomena, including phase-controlled chiral dynamics, separation of chiral enantiomers, and a mechanism to generate entangled states based on CCI.

Calibration and first results of relative humidity sensor MEDA HS on board M2020 rover

<p><span><span>MEDA HS is the relative humidity sensor </span></span><span><span>on the</span></span><span><span> Mars 2020 Perseverance rover provided by the Finnish Meteorological Institute (FMI). The sensor is a part of Mars Environmental Dynamic Analyzer (MEDA), a suite of environmental sensors provided by Centro de Astrobiología in Madrid, Spain. MEDA HS, along with METEO-H in ExoMars 2022 surface platform, is a successor of REMS-H on board Curiosity.</span></span></p><p><span><span>Calibration of relative humidity (RH) instruments for Mars missions is challenging due to the range of RH (from 0 to close to 100%) and temperature conditions (from about -90 ºC to + 22 ºC) that need to be simulated in the lab. Thermal gradients in different parts of the system </span></span><span><span>need to</span></span><span><span> be well known and controlled to ensure reliable reference RH readings. For MEDA HS the calibration tests have been performed for different models of MEDA HS in three Martian humidity simulator laboratories: FMI laboratory, Michigan Mars Environmental Chamber (MMEC) and DLR PASLAB (Planetary Analog Simulation Laboratory). </span></span></p><p><span><span>MEDA HS flight model was tested at FMI together with flight spare and ground reference models in low pressure dry CO</span></span><sub><span><span>2</span></span></sub><span><span> gas from +22ºC to -70ºC and in saturation conditions from -40ºC down to -70ºC. Further, the MEDA HS flight model final calibration is complemented by calibration data transferred from an identical ground reference model which has gone through rigorous testing also after the flight model delivery. During the test campaign at DLR PASLAB that started in Autumn 2020, MEDA HS has </span></span><span><span>been calibrated</span></span><span><span> over the full relative humidity scale</span></span><span><span> between -70 to -40ºC in CO</span></span><sub><span><span>2</span></span></sub><span><span> in the pressure ranges from 5.5 to 9.5 hPa, representative of Martian surface atmospheric pressure. The results can be extrapolated to higher and lower temperatures.</span></span></p><p><span>In this presentation the final flight calibration and performance of the MEDA HS will be presented together with first results expected from the surface of Mars by the Perseverance rover.</span></p>

Noncontact restoration of missing parts of stone Buddha statue based on three-dimensional virtual modeling and assembly simulation

Three-dimensional (3D) digital technology is an essential conservation method that complements the traditional restoration technique of cultural artifacts. In this study, 3D scanning, virtual restoration modeling, and 3D printing were used as a noncontact approach for restoring a damaged stone-seated Bodhisattva (stone Buddha statue). First, a 3D model with an average point density of 0.2 mm was created by integrating the fixed high-precision scanning of the exterior and the handheld mid-precision scanning of the interior excavated hole. Using a 3D deterioration map of the stone Buddha statue, the area of the missing parts was measured to be 400.1 cm2 (5.5% of the total area). Moreover, 257.1 cm2 (64.2% of the missing part area) of four parts, including the head, surrounding area of the Baekho, right ear, and right eye, for which symmetry was applicable for modeling or there could be ascertainable historical evidence for the total missing parts, was selected for restoration. The virtual restoration of the missing parts of the stone Buddha statue was performed using a haptic modeling system in the following order. First, the location of the three fragments detached from the head was determined. Next, a reference model was selected, and its symmetrization and modification with respect to the original model were conducted. Further, estimation modeling and outer shape description were achieved through historical research and consultation with experts. The heuristic-based assembly suitability of the created virtual restoration model (461 cm3) was verified by design mockup printing and digital–analog simulation. In particular, to address assembly interference, the interface surface was modified and reprocessed several times. Accordingly, the volume of the final design mockup decreased by 5.2% (437 cm3). Photopolymerization 3D printing technology was used for the actual restoration of the stone Buddha statue, and considering the surface roughness, the layer thickness of the material used for restoration was set at 0.10 mm. Finally, the surface of the printed output was colored to prevent yellowing and joined to the missing parts of the stone Buddha statue. This study presents a remarkable case of shifting from the traditional manual-contact method to the contactless digital method for restoring artifacts and is expected to largely contribute to increasing the usability of digital technologies in the restoration of cultural artifacts.

Noncontact restoration of missing parts of stone Buddha statue based on three-dimensional virtual modeling and assembly simulation

Three-dimensional (3D) digital technology is one of the most essential conservation methods that complements the traditional technique of the restoration of cultural artifacts. In this study, 3D scanning, virtual restoration modeling, and 3D printing were used as a non-contact approach for the restoration of a damaged stone seated Bodhisattva (stone Buddha statue). First, a three-dimensional model with an average point density of 0.2 mm was created by integrating the fixed high-precision scanning of the exterior and the handheld mid-precision scanning of the interior excavated hole. Through a 3D deterioration map of the stone Buddha statue, the area of the missing parts was measured as 400.1 cm 2 (5.5% of the total area). Moreover, 257.1 cm 2 (64.2% of the missing part area) of four parts such as the head, the surrounding area of the Baekho, the right ear, and the right eye, for which symmetry was applicable for modeling or there could be ascertainable historical evidence for the total missing parts, was selected for restoration. The virtual restoration of the missing parts of the stone Buddha statue was performed using a haptic modeling system in the following order. First, the location of the three fragments detached from the head was determined. Next, the reference model was selected, and its symmetrization and modification with respect to the original were conducted. Also, estimation modeling and outer shape description were performed through historical research and consultation with experts. The created virtual-restoration model’s (461 cm 3 ) heuristic-based assembly suitability was verified by design mock-up printing and digital–analog simulation. In particular, to address the assembly interference, the interface surface was modified and reprocessed several times. Accordingly, the final design mock-up’s volume size was decreased by 5.2% (437 cm 3 ). Photopolymerization 3D printing technology was used for the actual restoration of the stone Buddha statue and the layer thickness of the material used was set as 0.10 mm considering the surface roughness. Finally, the surface of the printed output was colored to prevent yellowing and joined to the missing part of the stone Buddha statue. This study presents a great case to shift from the traditional manual-contact method to the contactless digital method for the restoration of artifacts and is expected to largely contribute to increasing the usability of digital technologies in the restoration of cultural artifacts.

Non-contact restoration of missing parts of stone Buddha statue based on three-dimensional virtual modeling and assembly simulation

Three-dimensional (3D) digital technology is one of the most essential conservation methods that complements the traditional technique of the restoration of cultural artifacts. In this study, 3D scanning, virtual restoration modeling, and 3D printing were used as a non-contact approach for the restoration of a damaged stone seated Bodhisattva (stone Buddha statue). First, a three-dimensional model with an average point density of 0.2 mm was created by integrating the fixed high-precision scanning of the exterior and the handheld mid-precision scanning of the interior excavated hole. Through a 3D deterioration map of the stone Buddha statue, the area of the missing parts was measured as 400.1 cm 2 (5.5% of the total area). Moreover, 257.1 cm 2 (64.2% of the missing part area) of four parts such as the head, the surrounding area of the Baekho, the right ear, and the right eye, for which symmetry was applicable for modeling or there could be ascertainable historical evidence for the total missing parts, was selected for restoration. The virtual restoration of the missing parts of the stone Buddha statue was performed using a haptic modeling system in the following order. First, the location of the three fragments detached from the head was determined. Next, the reference model was selected, and its symmetrization and modification with respect to the original were conducted. Also, estimation modeling and outer shape description were performed through historical research and consultation with experts. The created virtual-restoration model’s (461 cm 3 ) heuristic-based assembly suitability was verified by design mock-up printing and digital–analog simulation. In particular, to address the assembly interference, the interface surface was modified and reprocessed several times. Accordingly, the final design mock-up’s volume size was decreased by 5.2% (437 cm 3 ). Photopolymerization 3D printing technology was used for the actual restoration of the stone Buddha statue and the layer thickness of the material used was set as 0.10 mm considering the surface roughness. Finally, the surface of the printed output was colored to prevent yellowing and joined to the missing part of the stone Buddha statue. This study presents a great case to shift from the traditional manual-contact method to the contactless digital method for the restoration of artifacts and is expected to largely contribute to increasing the usability of digital technologies in the restoration of cultural artifacts.