Critical Block Research Articles

Low-level visual attention and its relation to joint attention in autism spectrum disorder

Visual attention is integral to social interaction and is a critical building block for development in other domains (e.g., language). Furthermore, atypical attention (especially joint attention) is one of the earliest markers of autism spectrum disorder (ASD). The current study assesses low-level visual attention and its relation to social attentional processing in youth with ASD and typically developing (TD) youth, aged 7 to 18 years. The findings indicate difficulty overriding incorrect attentional cues in ASD, particularly with non-social (arrow) cues relative to social (face) cues. The findings also show reduced competition in ASD from cues that remain on-screen. Furthermore, social attention, autism severity, and age were all predictors of competing cue processing. The results suggest that individuals with ASD may be biased towards speeded rather than accurate responding, and further, that reduced engagement with visual information may impede responses to visual attentional cues. Once attention is engaged, individuals with ASD appear to interpret directional cues as meaningful. These findings from a controlled, experimental paradigm were mirrored in results from an ecologically valid measure of social attention. Attentional difficulties may be exacerbated during the complex and dynamic experience of actual social interaction. Implications for intervention are discussed.

Design Considerations for Reconfigurable Delay Circuit to Emulate System Critical Paths

The design, analysis, and implementation of an accurate delay circuit used to synthesize critical paths in a microprocessor system are presented. The delay circuit includes a novel 64-step programmable calibration delay line that is highly uniform across a wide range of supply voltages and a reconfigurable delay path with tunable delay sensitivity to voltage variations. The calibration delay line generates delay step in picosecond range, which is less than 1% of the clock cycle time for the microprocessor. The reconfigurable path is capable of increasing voltage sensitivity of the delay circuit by 40% and emulating the steeper frequency versus voltage slope of the microprocessor in low-voltage domain. The proposed circuit is implemented inside the critical path monitor block placed on a test microprocessor core fabricated using 22-nm silicon-on-insulator CMOS process. Measurement results from nine test cores show that the circuit tracks microprocessor timing margin change with an error less than 1.3% of the core operating frequency over a wide supply voltage range.

Heat Transfer and Entropy Generation in a Porous Square Enclosure in Presence of an Adiabatic Block

The present work investigates the thermal aspects of a differentially heated porous square enclosure in the presence of an adiabatic block of different block sizes utilizing Darcy–Rayleigh number in the range of 1–10,000 with Darcy number $$10^{-2}$$ – $$10^{-6}$$ . Heatlines and Nusselt number, streamlines, and entropy generation are used for the analysis of heat transfer, flow circulation, and irreversibility production in the enclosure. The study reveals that the presence of an adiabatic block affects the heat transfer process severely, and three different zones of heat transfer are identified. These are namely the zone of heat transfer augmentation, the zone of heat transfer augmentation along with entropy generation reduction, and the zone of both heat transfer and entropy generation reduction. It is also found that the presence of an adiabatic block can enhance heat transfer up to a certain critical block size; thereafter, further increasing in block size reduces the heat transfer rate. An optimal block size where the heat transfer enhancement is maximum is observed to be smaller than the critical block size. The study demonstrates the analyses of heat transfer and entropy generation for a better thermal design of a system. This study is also extended for higher Prandtl number fluids.

VINERy

Information Extraction (IE) is the key technology enabling analytics over unstructured and semi-structured data. Not surprisingly, it is becoming a critical building block for a wide range of emerging applications. To satisfy the rising demands for information extraction in real-world applications, it is crucial to lower the barrier to entry for IE development and enable users with general computer science background to develop higher quality extractors. In this demonstration 1 , we present VINERy, an intuitive yet expressive visual IDE for information extraction. We show how it supports the full cycle of IE development without requiring a single line of code and enables a wide range of users to develop high quality IE extractors with minimal efforts. The extractors visually built in VINERY are automatically translated into semantically equivalent extractors in a state-of-the-art declarative language for IE. We also demonstrate how the auto-generated extractors can then be imported into a conventional Eclipse-based IDE for further enhancement. The results of our user studies indicate that VINERY is a significant step forward in facilitating extractor development for both expert and novice IE developers.

Numerical Investigation of the Effect of the Location of Critical Rock Block Fracture on Crack Evolution in a Gob-side Filling Wall

Generation, propagation, and coalescence of the shear and tensile cracks in the gob-side filling wall are significantly affected by the location of the fracture of the critical rock block. The Universal Discrete Element Code software was used to investigate crack evolution characteristics in a gob-side filling wall and the parameter calibration process for various strata and the filling wall was clearly illustrated. The cracks in both the filling wall and the coal wall propagate inward in a V-shape pattern with dominant shear cracks generated initially. As the distance between the fracture and the filling wall decreases, the number of cracks in the filling wall decreases, and the stability of the filling wall gradually improves; thus, by splitting the roof rock at the optimal location, the filling wall can be maintained in a stable state. Additionally, we conducted a sensitivity analysis that demonstrated that the higher the coal seam strength, the fewer cracks occur in both the filling wall and the coal wall, and the less failure they experience. With the main roof fracturing into a cantilever structure, the higher the immediate roof strength, the fewer cracks are in the filling wall. With the critical rock block fracturing above the roadway, an optimal strength of the immediate roof can be found that will stabilize the filling wall. This study presents a theoretical investigation into stabilization of the filling wall, demonstrating the significance of pre-splitting the roof rock at a desirable location.

2.45 GHz 0.8 mW voltage-controlled ring oscillator (VCRO) in 28 nm fully depleted silicon-on-insulator (FDSOI) technology

MOS bulk transistor is reaching its limits: sub-threshold slope (SS), drain induced barrier lowering (DIBL), threshold voltage (VT) and VDD scaling slowing down, more power dissipation, less speed gain, less accuracy, variability and reliability issues. Fully depleted devices are mandatory to continue the technology roadmap. FDSOI technology relies on a thin layer of silicon that is over a buried oxide (BOx). Called ultra thin body and buried oxide (UTBB) transistor, FDSOI transistors correspond to a simple evolution from conventional MOS bulk transistor. The capability to bias the back-gate allows us to implement calibration techniques without adding transistors in critical blocks. We have illustrated this technique on a very low power voltage-controlled oscillator (VCO) based on a ring oscillator (RO) designed in 28 nm FDSOI technology. Despite the fact that such VCO topology exhibits a larger phase noise, this design will address aggressively the size and power consumption reduction. Indeed we are using the efficient back-gate biasing offered by the FDSOI MOS transistor to compensate the mismatches between the different inverters of the ring oscillator to decrease jitter and phase noise. We will present the reasons which led us to use the FDSOI technology to reach the specifications of this PLL. The VCRO exhibits a 0.8 mW power consumption, with a phase noise about −94 dBc/Hz@1 MHz.

A low power bioimpedance module for wearable systems

In the emerging field of wearable systems for remote monitoring of physiological parameters, the measurement of bioimpedance has the potential to provide many useful information. On the other hand, in this scenario, an optimization of power consumption of the circuit is crucial. A low power architecture for the measurement of bioimpedance was identified in this work. It reduces the consumption in the most critical blocks of the system: the current driver, the signal sensing and the demodulator. The device was prototyped and electrically characterized. The compromise between power consumption reduction and the increase in electrical noise was analysed and an effective signal processing technique was developed, showing that it is possible to achieve a signal to noise ratio good enough to enable applications like respiration monitoring (breathing rate and amplitude) or cardiac output estimation. Preliminary tests on healthy subjects showed a good correlation with spirometer, for breathing monitoring, and with Doppler echocardiography, for cardiac output. Thanks to the good functionality and the reduced current consumption (750μA at 2.8V power supply was obtained with a discrete-components implementation) the module resulted suitable for the integration in wearable devices for remote monitoring of physiological parameters, or other low power applications.

Soluble Silver Acetylide for the Construction and Structural Conversion of All-Alkynyl-Stabilized High-Nuclearity Homoleptic Silver Clusters

Silver acetylide complex [Ag(ArC≡C)]n (Ar = 3,5-di-tert-butylphenyl) with unprecedented high solubility in common organic solvents has been designed and synthesized. The high solubility is due to two bulky tert-butyl substituents on the phenyl ring. This feature is significant to construct and isolate single crystals of all-alkynyl-stabilized silver clusters, which are crucial to investigate the intrinsic binding interaction and coordination modes between Ag(I) and ethynide ligands. Crystallization of [Ag(ArC≡C)]n under various conditions resulted in three high-nuclearity homoleptic silver acetylide clusters, namely, [Ag21(ArC≡C)20](OH) (1), [Ag16(ArC≡C)16] (2), and [Ag15(ArC≡C)15] (3). Complex 1 has a [Ag21] cluster protected by twenty 3,5-di-tert-butyl-phenylethynide ligands. Complexes 2 and 3 have neutral [Ag16] and [Ag15] clusters, respectively. In addition to these homoleptic silver clusters, two new silver acetylides [Ag20(ArC≡C)16(CH3COO)4] (4) and [Ag22(ArC≡C)16(NO3)4(CH3CH2OH)4](OH)2 (5) were synthesized. The acetate and nitrate anions in these structures are more like counterions instead of acting as critical building blocks or templates for cluster assembly. These results illustrated the significance of 3,5-di-tert-butyl-phenylethynide ligands in the construction and stabilization of high-nuclearity silver clusters. Analysis of structures of 1–5 revealed several novel coordination modes between Ag(I) and ethynide ligands, which contributed considerably to our knowledge of Ag(I)–ethynide binding interactions.

Reading Comprehension and Autism in the Primary General Education Classroom

Reading comprehension is a critical building block for effective early literacy development. Many students with autism spectrum disorder demonstrate difficulties in reading comprehension. These difficulties may be attributed to deficits in Theory of Mind, Weak Central Coherence, and Executive Functioning. Given the rise in the number of students with this disability participating in the general education setting, practitioners need to acquire the background knowledge on how to effectively teach this population. The purpose of this article is to introduce practitioners to a step-by-step guide for teaching reading comprehension, the characteristics of autism spectrum disorder that may impede students from acquiring reading comprehension, and evidenced-based practices that can be used to improve their comprehension abilities.

Undershoot suppression technique for fully integrated pulse‐width modulated switching converters

A shunt-regulation control technique is presented to improve the load transient performance of fully integrated high-frequency converters. The undershoot voltage, which used to be limited by the system loop response and the nanofarad range small on-chip capacitor, is significantly suppressed. The proposed converter is simulated by a standard 0.13 μm CMOS process using a 6 nH inductor and 10 nF capacitor under different process corners with parasitics extracted from the layout of critical blocks. Compared to a conventional converter with the bandwidth pushed to the limit, the undershoot voltage is reduced from 360 to 100 mV with a transient step of 150–550 mA in 100 ps.

Analyzing the Efficiency of L1 Caches for Reliable Hybrid-Voltage Operation Using EDC Codes

The increasing demand for highly miniaturized battery-powered ultralow cost systems (e.g., below 1 dollar) in emerging applications such as body, urban life and environment monitoring, and so on, has introduced many challenges in chip design. Such applications require high performance occasionally and very little energy consumption during most of the time to extend battery lifetime. In addition, they require real-time guarantees. Caches have been shown to be the most critical blocks in these systems due to their high energy/area consumption and hard-to-predict behavior. New, simple, hybrid-voltage operation (high V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cc</sub> and ultralow V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cc</sub> ), single-V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cc</sub> domain L1 cache architectures based on replacing energy-hungry bitcells (e.g., 10T) by more energy-efficient and smaller cells (e.g., 8T) enhanced with error detection and correction codes have been recently proposed. Such designs provide significant energy and area efficiency without jeopardizing reliability levels to still provide strong performance guarantees. In this brief, we analyze the efficiency of these designs during ultralow voltage operation. We identify the limits of such approaches by finding an energy-optimal voltage region through experimental models. The experimental results show that area efficiency is always achieved in the range 200-400 mV, whereas both energy and area gains occur above 250 mV, i.e., in near-threshold regime.

Investigation of Stability of the Critical Rock Blocks that Initiated the Jiweishan Landslide in China

The objective of the paper is to investigate the initiation of the Jiweishan landslide by simulating the field geological conditions around and inside a selected critical rock block and then to study its stability through 3-D discontinuum stress analysis. The study led to the following main conclusions: (1) The mining excavations that occurred underneath the investigated block at the landslide site, the friction angle of T2 discontinuities and sliding plane and the dip angle of the sliding plane seem to be the most important factors with respect to the instability of the investigated block; (2) It seems that the friction angle of T2 discontinuities and sliding plane need to drop to a value between 5° and 10° for the investigated block to be unstable. This means that the rainfall and karstification have played important roles in reducing the said friction angle and contributed to the failure of the investigated block. (3) The northern part of the investigated block (key block) had moved out first from the top of the mountain in a direction parallel to the strike of the north boundary discontinuity plane (T2) and had undergone shear failure on the T2 surface as well as on a weak shale layer (the sliding plane) and the remaining part of the investigated block (driving block) had moved along a direction slightly east of the north direction and had undergone shear failure on the sliding plane and separation from southern and western boundary discontinuity planes (T0 and T1) to fill the empty space created by the key block to initiate the Jiweishan landslide.

Transparent subdiffraction optics: nanoscale light confinement without metal

The integration of nanoscale electronics with conventional optical devices is restricted by the diffraction limit of light. Metals can confine light at the subwavelength scales needed, but they are lossy, while dielectric materials do not confine evanescent waves outside a waveguide or resonator, leading to cross talk between components. We introduce a paradigm shift in light confinement strategy and show that light can be confined below the diffraction limit using completely transparent artificial media. Our approach relies on controlling the optical momentum of evanescent waves, an important electromagnetic property overlooked in photonic devices. For practical applications, we propose a class of waveguides using this approach that outperforms the cross talk performance by 1 order of magnitude as compared to any existing photonic structure. Our work overcomes a critical stumbling block for nanophotonics by completely averting the use of metals and can impact electromagnetic devices from the visible to microwave frequency ranges.

A Bit-by-Bit Re-Writable Eflash in a Generic 65 nm Logic Process for Moderate-Density Nonvolatile Memory Applications

Embedded nonvolatile memory (eNVM) is considered to be a critical building block in future system-on-chip and microprocessor systems. Various eNVM technologies have been explored for high-density applications including dual-poly embedded flash (eflash), FeRAM, STT-MRAM, and RRAM. On the other end of the spectrum, logic-compatible eNVM such as e-fuse, anti-fuse, and single-poly eflash memories have been considered for moderate-density low-cost applications. In particular, single-poly eflash memory has been gaining momentum as it can be implemented in a generic logic process while supporting multiple program-erase cycles. One key challenge for single-poly eflash is enabling bit-by-bit re-write operation without a boosted bitline voltage as this could cause disturbance issues in the unselected wordlines. In this work, we present details of a bit-by-bit re-writable eflash memory implemented in a generic 65 nm logic process which addresses this key challenge. The proposed 6 T eflash memory cell can improve the overall cell endurance by eliminating redundant program/erase cycles while preventing disturbance issues in the unselected wordlines. We also provide details of special high voltage circuits such as a voltage-doubler based charge pump circuit and a multistory high-voltage switch, for generating a reliable high-voltage output without causing damage to the standard logic transistors.

Can adjustment to accented speech affect native language perception?

The human auditory system can quickly accommodate foreign-accented speech. However, the cognitive mechanisms underlying perceptual adjustment to non-native speech are not fully understood. The current study examined the perceptual consequences of adaptation toward foreign-accented speech on native language perception. Native English speakers performed an auditory shadowing task on word-length utterances in English. There were four blocks of trials. The words in the critical block (Block 3) were spoken by either a native American English speaker or a native Spanish speaker. The speaker in flanking blocks (Blocks 1–2, 4) was the same speaker, a different speaker with the same accent, or a different speaker with a different accent. Shadowing response times in the critical block were used to assess rapid perceptual adjustment and readjustment. Results showed that the nature of the preceding context influenced response times. Response times for items in the first quartile of the critical block were reliably slower when accent and talker changed than when accent and talker remained constant. These findings suggest that listeners develop perceptual expectations about ongoing speech, which when violated incur a short-term processing cost even for spoken words in the listeners’ native language.

High-Efficiency Wideband Rectifier for Single-Chip Batteryless Active Millimeter-Wave Identification (MMID) Tag in 65-nm Bulk CMOS Technology

This paper presents the development and demonstration of a high-efficiency rectifier for millimeter-wave-to-dc energy conversion. It is a critical circuit block that renders possible the use of a single CMOS chip die with no substrate and wiring, as the implementation of a batteryless, yet active tag for next-generation high data-rate millimeter-wave identification technologies. We also propose an architecture of a reader-tag system that addresses the underlying technical challenges. The rectifier is based on a differential drive cross-coupled topology that has been shown to work at UHF frequencies only so far. In this paper, we investigate significant challenges in implementing this topology at millimeter-wave frequencies with good power conversion efficiency (PCE). The analyses, design, and results presented in this work demonstrate the feasibility of achieving this by minimizing simultaneously the small on-resistance and the reverse leakage current in the MOS transistors, and by reducing losses and parasitic capacitances through proper transistor sizing and layout optimization. Using a standard 65-nm bulk CMOS process, a chip was designed, fabricated, and tested under different input and output loading conditions. The rectifier exhibits an overall PCE of 20% at 24 GHz, 18% at 35 GHz, and 11% at 60 GHz under RF available driving power of 6, 6, and 3 dBm, respectively, and output load resistance of 1, 1, and 2 kΩ, respectively. These PCE performances at millimeter-wave frequencies have never been reported in the literature.

Chain Length Dependence of Non-Surface Activity and Micellization Behavior of Cationic Amphiphilic Diblock Copolymers

The cationic and anionic amphiphilic diblock copolymers with a critical chain length and block ratio do not adsorb at the air/water interface but form micelles in solution, which is a phenomenon called "non-surface activity". This is primarily due to the high charge density of the block copolymer, which creates a strong image charge effect at the air/water interface preventing adsorption. Very stable micelle formation in bulk solution could also play an important role in the non-surface activity. To further confirm these unique properties, we studied the adsorption and micellization behavior of cationic amphiphilic diblock copolymers of poly(n-butyl acrylate)-b-poly(3-(methacryloyloxy)ethyl)trimethylammonium chloride) (PBA-b-PDMC) with different molecular weights of hydrophobic blocks but with the same ionic block length. These block copolymers were successfully prepared via consecutive reversible addition-fragmentation chain transfer (RAFT) polymerization. The block copolymer with the shortest hydrophobic block length was surface-active; the solution showed surface tension reduction and foam formation. However, above the critical block ratio, the surface tension of the solution did not decrease with increasing polymer concentration, and there was no foam formation, indicating lack of surface activity. After addition of 0.1 M NaCl, stable foam formation and slight reduction of surface tension were observed, which is reminiscent of the electrostatic nature of the non-surface activity. Fluorescence and dynamic and static light scattering measurements showed that the copolymer with the shortest hydrophobic block did not form micelles, while the block copolymers formed spherical micelles having radii of 25-30 nm. These observations indicate that micelle formation is also important for non-surface activity. Upon addition of NaCl, cmc did not decrease but rather increased as observed for non-surface-active block copolymers previously studied. The micelles formed were very stable, and their size decreased by only ∼5 nm after addition of 0.1 M NaCl.

Any Animal Whatever? Harmful Battery and Its Elements as Building Blocks of Moral Cognition

This article argues that the key elements of the prima facie case of harmful battery may form critical building blocks of moral cognition in both humans and nonhuman animals. By contrast, at least some of the rules and representations presupposed by familiar justifications to battery appear to be uniquely human. The article also argues that many famous thought experiments in ethics and many influential experiments in moral psychology rely on harmful battery scenarios without acknowledging this fact or considering its theoretical or empirical implications. The unifying factor in all these studies is goal-directed harmful contact, inflicted without consent or justification.

Improving energy benchmarking with self-reported data

Energy benchmarking for buildings has become increasingly important in government policy and industry practice for energy efficiency. The questions of how energy benchmarking is currently conducted, and how it might be improved using rapidly growing quantities of self-reported data, are examined. A case study of commercial office buildings in New York City demonstrates how the rapid growth in self-reported data presents both new opportunities and challenges for energy benchmarking for buildings. A critique is presented for the scoring methodology and data sources for Energy Star, one of the largest and most successful benchmarking certification schemes. Findings from recent studies are examined to illustrate how this certification currently works in the marketplace. Self-reported building energy data are rapidly growing in Portfolio Manager (the user interface to Energy Star) due to mandatory energy benchmarking laws, and can be used to improve Energy Star's current scoring methods. These self-reported data are tested and improved for analysis by applying theories and methods of data quality developed in computer science, statistics and data management. These new data constitute a critical building block for the development of energy efficiency policies, and will affect how government, consultants, and owners measure and compare building energy use.

Context effects on beauty ratings of photos: Building contrast effects that erode but cannot be knocked down.

The aesthetic value of photos is often evaluated alongside other photos (art galleries, photo albums). We examined the direction, duration, and resilience of the influence of a set of context photos on beauty ratings for a subsequent set of critical photos. Beauty ratings for a set of average-beauty photos of buildings were higher after viewing a set of low-beauty (vs. high-beauty) photos, regardless of whether the context photos depicted the same, similar, or different thematic content. This contrast effect persisted when participants were asked to avoid being influenced by the context photos, when the context photos were processed in a nonaesthetic task, and when the context and critical photos were made to seem more similar. Although we could not “knock down” these contrast effects, they “eroded” across the critical block as the groups’ recent experiences became more similar. Implications of our findings for theories of contrast/assimilation and aesthetics are discussed.