Environmental-Based Characterization of SoC-Based Instrumentation Systems for Stratified Testing

This paper proposes a novel environmental-based method for evaluating the good yield rate (GYR) of systems-on-chip (SoC) during fabrication. Testing and yield evaluation at high confidence are two of the most critical issues for the success of SoC as a viable technology. The proposed method relies on different features of fabrication, which are quantified by the so-called Fabrication environmental parameters (EPs). EPs can be highly correlated to the yield, so they are analyzed using statistical methods to improve its accuracy and ultimately direct the test process to an efficient execution. The novel contributions of the proposed method are: 1) to establish an adequate theoretical foundation for understanding the fabrication process of SoCs together with an assurance of the yield at a high confidence level and 2) to ultimately provide a realistic approach to SoC testing with an accurate yield evaluation. Simulations are provided to demonstrate that the proposed method significantly improves the confidence interval of the estimated yield as compared with existing testing methodologies such as random testing (RT)

High Confidence Testing for Instrumentation System-on-Chip with Unknown-Good-Yield

SoCs are in general built with embedded IP cores, each of which is procured from different IP providers with no prior information on known-good-yield (KGY). In practice, partial testing is a practical choice for assuring the yield of the product under the stringent time-to-market requirements. Therefore, a proper sampling technique is a key to high confidence testing and cost effectiveness. Based on previous research, this paper proposes a novel statistical testing technique for increasingly hybrid integrated systems fabricated on a single silicon die with no a-priori empirical yield data. This problem is referred to as the unknown-good-yield (UKGY) problem. The proposed testing method, referred to as regressive testing (RegT) in this paper, exploits another way around by using parameters (referred to as assistant variables (AV)) that are employed to evaluate the yields of randomly sampled SoCs and thereby estimating the good yield by using a regression analysis method with regard to confidence intervals. Numerous simulations are conducted to demonstrate the efficiency and effectiveness of the proposed RegT in comparison to characterization-based testing methods

Research and Technology 1995

This report selectively summarizes the NASA Lewis Research Center's research and technology accomplishments for fiscal year 1995. It comprises over 150 short articles submitted by the staff members of the technical directorates. The report is organized into six major sections: aeronautics, aerospace technology, space flight systems, engineering support, Lewis Research Academy, and technology transfer. A table of contents, an author index, and a list of NASA Headquarters program offices have been included to assist the reader in finding articles of special interest. This report is not intended to be a comprehensive summary of all research and technology work done over the past fiscal year. Most of the work is reported in Lewis-published technical reports, journal articles, and presentations prepared by Lewis staff members and contractors (for abstracts of these Lewis-authored reports, visit the Lewis Technical Report Server (LETRS) on the World Wide Web-http://letrs.lerc.nasa.gov/LeTRS/). In addition, university grants have enabled faculty members and graduate students to engage in sponsored research that is reported at technical meetings or in journal articles. For each article in this report, a Lewis contact person has been identified, and where possible, reference documents are listed so that additional information can be easily obtained. The diversity of topics attests to the breadth of research and technology being pursued and to the skill mix of the staff that makes it possible. For more information about Lewis' research, visit us on the World Wide web-http://www.lerc.nasa.gov

Microfluidics and Nanofluidics Handbook

The Microfluidics and Nanofluidics Handbook: Two-Volume Set comprehensively captures the cross-disciplinary breadth of the fields of micro- and nanofluidics, which encompass the biological sciences, chemistry, physics and engineering applications. To fill the knowledge gap between engineering and the basic sciences, the editors pulled together key individuals, well known in their respective areas, to author chapters that help graduate students, scientists, and practicing engineers understand the overall area of microfluidics and nanofluidics. Topics covered include Finite Volume Method for Numerical Simulation Lattice Boltzmann Method and Its Applications in Microfluidics Microparticle and Nanoparticle Manipulation Methane Solubility Enhancement in Water Confined to Nanoscale Pores Volume Two: Fabrication, Implementation, and Applications focuses on topics related to experimental and numerical methods. It also covers fabrication and applications in a variety of areas, from aerospace to biological systems. Reflecting the inherent nature of microfluidics and nanofluidics, the book includes as much interdisciplinary knowledge as possible. It provides the fundamental science background for newcomers and advanced techniques and concepts for experienced researchers and professionals

Genetic Insights into the Heterogeneity and Comorbidity of Substance Use Disorders

[eng] Substance use disorders (SUDs) are psychiatric disorders characterized by a recurring desire to continue taking a substance regardless of its destructive consequences. The etiology of SUDs is complex and multifactorial, where both genetic and environmental factors have an impact on the disease development. In addition, SUDs often co-occur at high prevalence with other psychiatric conditions, significantly impacting life expectancy, disease severity and societal burden. Over the past decade, genome-wide association studies (GWASs) have identified various risk loci for substance-specific SUD, as well as a shared genetic vulnerability for addiction. In addition, post-GWAS analyses have helped unravel the complex genetic architecture of SUDs, which can also involve an interplay of gene-environment interactions, and its relationship with comorbid mental health conditions. Current research in this field is making collective efforts to provide deeper and clearer knowledge into the genetic and environmental factors involved into the co-occurrence of SUDs and psychiatric disorders, which may be partially driving the high heterogeneity observed in SUDs, and the biological mechanisms driving these relationships. The present thesis comprises two studies that leverage in-house clinical cohorts, with both phenotypical and genetic data available, and state-of-the-art genomic techniques to investigate the shared genetic liability between SUDs and co-occurring traits, and to shed light into the genetic underpinnings of SUDs heterogeneity. The first study particularly focused on the relationship between SUDs and attention-deficit and hyperactivity disorder (ADHD). In this study, we tested whether the genetic liability to five SUD-related phenotypes share a common genetic background in both the general population and clinically diagnosed ADHD individuals, using an in-house sample of 989 subjects and polygenic scores (PGSs) analyses. We further explored the genetic overlap and the causal relationship between ADHD and SUDs using genetic correlation and Mendelian randomization analyses. Our results confirmed a significant genetic correlation between ADHD and SUDs and supported the current literature on the causal effect of the genetic liability to ADHD on the risk for SUDs. We provided novel findings on the effect of the genetic liability to lifetime cannabis use on an increased risk for ADHD and found evidence of a shared genetic background underlying SUDs between general population and ADHD, at least for lifetime cannabis use, alcohol dependence and smoking initiation. The second study aimed to disentangle SUDs heterogeneity using multidimensional data from a deeply phenotyped SUDs cohort of 1,427 individuals and PGSs for comorbid psychiatric disorders, behavioral and other related traits. We systematically explored the associations between the PGSs and 39 SUD-related phenotypes, and performed PGSs-environment interaction analyses using information on lifetime emotional, physical and/or sexual abuse. Our results revealed different patterns of associations between the genetic liability for mental health-related traits and SUD-related phenotypes, which may help explain part of the heterogeneity observed in SUDs. We also found evidence of a PGS-environment interaction showing that genetic liability for suicide attempt worsened the psychiatric status in SUDs individuals with a history of emotional physical and/or sexual abuse. Overall, the results of the present thesis provide new insights into the genetic overlap and causal relationships between SUDs and ADHD and contribute to a better understanding of the role of the genetic liability for psychiatric disorders and related traits, as well as its interaction with adverse life experiences, in the complexity of SUD heterogeneity. Lastly, this thesis provides a general discussion of the findings, which offers an extensive interpretation of the results in the context of existing literature, discusses the main methodological implications and outlines prospective directions for advancing in this line of research.[cat] Els trastorns per l'ús de substàncies (TUS) són trastorns psiquiàtrics caracteritzats per un desig recurrent de continuar prenent una o diverses substàncies, independentment de les seves conseqüències destructives. L'etiologia dels TUS és complexa i multifactorial, on tant factors genètics com ambientals tenen un impacte en el desenvolupament de la malaltia. A més, els TUS sovint es presenten simultàniament amb altres trastorns psiquiàtrics, afectant significativament la severitat de la malaltia, l’esperança de vida i la càrrega en la societat. Durant l'última dècada, els estudis d'associació del genoma complet (GWASs) han identificat diverses variants genètiques de risc per a TUS de substàncies específiques, així com una vulnerabilitat genètica compartida per a l'addicció. A més, les anàlisis post-GWAS han ajudat a desxifrar l'arquitectura genètica complexa dels TUS, que també pot implicar la interacció entre gens i ambient, i la seva relació amb trastorns de salut mental comòrbids. La recerca actual en aquest camp està focalitzada en profunditzar en el coneixement sobre els factors genètics i ambientals involucrats en la coexistència del TUS i trastorns psiquiàtrics, el qual pot ser parcialment responsable de l’alta heterogeneïtat observada en el TUS, i els mecanismes biològics implicats. La present tesi està composta per dos estudis que utilitzen cohorts clíniques, amb dades fenotípiques i genètiques disponibles, i tècniques genòmiques actuals per explorar la carga genètica compartida entre els TUS i els trets comòrbids, i per investigar la heterogeneïtat dels TUS des del punt de vista genètic. El primer estudi es centra particularment en la relació entre els TUS i el trastorn per dèficit d’atenció i hiperactivitat (TDAH). En aquest estudi, vam testar si la càrrega genètica per a cinc fenotips de TUS comparteixen una base genètica comuna en la població general i en individus amb TDAH, fent servir un mostra interna de 989 individus i anàlisis de puntuacions poligèniques (PGSs). Seguidament, vam explorar el solapament genètic i la relació causal entre el TDAH i els TUS utilitzant anàlisis de correlació genètica i de randomització mendeliana. Els nostres resultats confirmen una base genètic comuna entre el TDAH i els TUS i donen suport a la literatura actual sobre l'efecte causal de la càrrega genètica pel TDAH en el risc de TUS. A més, descrivim per primera vegada l'efecte causal de la càrrega genètica per a l'ús de cànnabis en el risc de TDAH i trobem evidències d'un component genètic compartit subjacent als TUS en la població general i en els individus amb TDAH, almenys per a l'ús de cànnabis, la dependència a l'alcohol i l'inici del consum de tabac. El segon estudi té com a objectiu desxifrar la heterogeneïtat dels TUS utilitzant dades multidimensionals d'una cohort de TUS de 1,427 individus dels quals es disposa una àmplia informació fenotípica, i PGSs per a trastorns psiquiàtrics comòrbids, trets del comportament i altres trets relacionats. Vam explorar les associacions entre els PGSs i 39 fenotips de TUS, i vam portar a terme anàlisis d’interacció PGS-ambient utilitzant informació sobre abús emocional, físic i/o sexual al llarg de la vida. Els nostres resultats revelen diferents patrons d'associacions entre la càrrega genètica per a trets relacionats amb la salut mental i fenotips de TUS, el que pot ajudar a explicar part de la heterogeneïtat observada en els TUS. També trobem evidència d'una interacció PGS-ambient que mostra que la càrrega genètica per a intents de suïcidi empitjora l'estat psiquiàtric en individus amb TUS que han patit abús emocional, físic i/o sexual. En conjunt, els resultats de la present tesi aporten noves perspectives sobre el solapament genètic i les relacions causals entre els TUS i el TDAH i contribueixen a una millor comprensió del paper de la càrrega genètica pels trastorns psiquiàtrics i trets relacionats, així com la seva interacció amb experiències adverses al llarg de la vida, en la complexitat de la heterogeneïtat dels TUS. Finalment, aquesta tesi ofereix una discussió general, la qual proporciona una extensa interpretació dels resultats en el context de la literatura existent, discuteix les principals implicacions metodològiques i detalla les futures direccions per avançar en aquesta línia de investigació

Hydrogen Research for Spaceport and Space-Based Applications: Fuel Cell Projects

The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Fuel cell research focused on proton exchange membranes (PEM), solid oxide fuel cells (SOFC). Specific technologies included aircraft fuel cell reformers, new and improved electrodes, electrolytes, interconnect, and seals, modeling of fuel cells including CFD coupled with impedance spectroscopy. Research was conducted on new materials and designs for fuel cells, along with using embedded sensors with power management electronics to improve the power density delivered by fuel cells. Fuel cell applications considered were in-space operations, aviation, and ground-based fuel cells such as; powering auxiliary power units (APUs) in aircraft; high power density, long duration power supplies for interplanetary missions (space science probes and planetary rovers); regenerative capabilities for high altitude aircraft; and power supplies for reusable launch vehicles

Pilot study for subgroup classification for autism spectrum disorder based on dysmorphology and physical measurements in Chinese children

Poster Sessions: 157 - Comorbid Medical Conditions: abstract 157.058 58BACKGROUND: Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder affecting individuals along a continuum of severity in communication, social interaction and behaviour. The impact of ASD significantly varies amongst individuals, and the cause of ASD can originate broadly between genetic and environmental factors. Objectives: Previous ASD researches indicate that early identification combined with a targeted treatment plan involving behavioural interventions and multidisciplinary therapies can provide substantial improvement for ASD patients. Currently there is no cure for ASD, and the clinical variability and uncertainty of the disorder still remains. Hence, the search to unravel heterogeneity within ASD by subgroup classification may provide clinicians with a better understanding of ASD and to work towards a more definitive course of action. METHODS: In this study, a norm of physical measurements including height, weight, head circumference, ear length, outer and inner canthi, interpupillary distance, philtrum, hand and foot length was collected from 658 Typical Developing (TD) Chinese children aged 1 to 7 years (mean age of 4.19 years). The norm collected was compared against 80 ASD Chinese children aged 1 to 12 years (mean age of 4.36 years). We then further attempted to find subgroups within ASD based on identifying physical abnormalities; individuals were classified as (non) dysmorphic with the Autism Dysmorphology Measure (ADM) from physical examinations of 12 body regions. RESULTS: Our results show that there were significant differences between ASD and TD children for measurements in: head circumference (p=0.009), outer (p=0.021) and inner (p=0.021) canthus, philtrum length (p=0.003), right (p=0.023) and left (p=0.20) foot length. Within the 80 ASD patients, 37(46%) were classified as dysmorphic (p=0.00). CONCLUSIONS: This study attempts to identify subgroups within ASD based on physical measurements and dysmorphology examinations. The information from this study seeks to benefit ASD community by identifying possible subtypes of ASD in Chinese population; in seek for a more definitive diagnosis, referral and treatment plan.published_or_final_versio