United States Army Combat Capabilities Development Command

Procedures are given in the report for determining statistically whether the highest observation, or the lowest observation, or the highest and lowest observations, or the two highest observations, or the two lowest observations, or perhaps more of the observations in the sample may be considered to be outlying observations or discrepant values. Statistical tests of significance are useful in this connection either in the absence of assignable physical causes or to support a practical judgement that some of the experimental observations are aberrant. Both the statistical formulae and illustrative applications of the procedures to practical examples are given, thus representing a rather complete treatment of significance tests for outliers in single univariate samples.

The automatic recognition of the modulation format of a detected signal, the intermediate step between signal detection and demodulation, is a major task of an intelligent receiver, with various civilian and military applications. Obviously, with no knowledge of the transmitted data and many unknown parameters at the receiver, such as the signal power, carrier frequency and phase offsets, timing information and so on, blind identification of the modulation is a difficult task. This becomes even more challenging in real-world scenarios with multipath fading, frequency-selective and time-varying channels. With this in mind, the authors provide a comprehensive survey of different modulation recognition techniques in a systematic way. A unified notation is used to bring in together, under the same umbrella, the vast amount of results and classifiers, developed for different modulations. The two general classes of automatic modulation identification algorithms are discussed in detail, which rely on the likelihood function and features of the received signal, respectively. The contributions of numerous articles are summarised in compact forms. This helps the reader to see the main characteristics of each technique. However, in many cases, the results reported in the literature have been obtained under different conditions. So, we have also simulated some major techniques under the same conditions, which allows a fair comparison among different methodologies. Furthermore, new problems that have appeared as a result of emerging wireless technologies are outlined. Finally, open problems and possible directions for future research are briefly discussed.

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTMetal–Organic Frameworks for Air Purification of Toxic ChemicalsJared B. DeCoste*† and Gregory W. Peterson*‡View Author Information† Leidos Inc., P.O. Box 68, Gunpowder, Maryland 21010, United States‡ Edgewood Chemical Biological Center, U.S. Army Research, Development, and Engineering Command, 5183 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States*J.B.D.: phone, 410-417-2815; e-mail: [email protected]*G.W.P.: phone, 410-436-9794; e-mail, [email protected]Cite this: Chem. Rev. 2014, 114, 11, 5695–5727Publication Date (Web):April 21, 2014Publication History Received7 November 2013Published online21 April 2014Published inissue 11 June 2014https://pubs.acs.org/doi/10.1021/cr4006473https://doi.org/10.1021/cr4006473review-articleACS PublicationsCopyright © 2014 American Chemical SocietyRequest reuse permissionsArticle Views16462Altmetric-Citations824LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Adsorption,Ammonia,Materials,Metal organic frameworks,Oxides Get e-Alerts

We suggest that expert programmers have and use two types of programming knowledge: 1) programming plans, which are generic program fragments that represent stereotypic action sequences in programming, and 2) rules of programming discourse, which capture the conventions in programming and govern the composition of the plans into programs. We report here on two empirical studies that attempt to evaluate the above hypothesis. Results from these studies do in fact support our claim.

Hexagonal boron nitride (h-BN) has emerged as a strong candidate for two-dimensional (2D) material owing to its exciting optoelectrical properties combined with mechanical robustness, thermal stability, and chemical inertness. Super-thin h-BN layers have gained significant attention from the scientific community for many applications, including nanoelectronics, photonics, biomedical, anti-corrosion, and catalysis, among others. This review provides a systematic elaboration of the structural, electrical, mechanical, optical, and thermal properties of h-BN followed by a comprehensive account of state-of-the-art synthesis strategies for 2D h-BN, including chemical exfoliation, chemical, and physical vapor deposition, and other methods that have been successfully developed in recent years. It further elaborates a wide variety of processing routes developed for doping, substitution, functionalization, and combination with other materials to form heterostructures. Based on the extraordinary properties and thermal-mechanical-chemical stability of 2D h-BN, various potential applications of these structures are described.

Electrolytes and the associated interphases constitute the critical components to support the emerging battery chemistries that promise tantalizing energy but involve drastic phase and structure complications. Designing better electrolytes and interphases holds the key to the success of these batteries. As the only component that interfaces with every other component in the device, an electrolyte must satisfy multiple criteria simultaneously. These include transporting ions while insulating electrons between the electrodes and maintaining stability against electrodes of extreme chemical natures: the strongly oxidative cathode and the strongly reductive anode. In most advanced batteries, the two electrodes operate at potentials far beyond the thermodynamic stability limits of electrolytes, so the stability therein has to be realized kinetically through an interphase formed from the sacrificial reactions between electrolyte and electrodes.

Low-dimensional materials have been examined as electrocatalysts for the hydrogen evolution reaction (HER). Among them, two-dimensional transition metal dichalcogenides (2D-TMDs) such as MoS2 have been identified as potential candidates. However, the performance of TMDs toward HER in both acidic and basic media remains inferior to that of noble metals such as Pt and its alloys. This calls for investigating the influence of controlled defect engineering of 2D TMDs on their performance toward hydrogen production. Here, we explored the HER activity from defective multilayered MoS2 over a large range of surface S vacancy concentrations up to 90%. Amorphous MoS2 and 2H MoS2 with ultrarich S vacancies demonstrated the highest HER performance in acid and basic electrolytes, respectively. We also report that the HER performance from multilayered MoS2 can be divided into two domains corresponding to “point defects” at low concentrations of surface S vacancies (Stage 1) and large regions of undercoordinated Mo atoms for high concentrations of surface S vacancies (Stage 2). The highest performance is obtained for Stage 2 in the presence of undercoordinated Mo atoms with a TOF of ∼2 s–1 at an overpotential of 160 mV in 0.1 M KOH which compares favorably to the best results in the literature. Overall, our work provides deeper insight on the HER mechanism from defected MoS2 and provides guidance for the development of defect-engineered TMD-based electrocatalysts.

An empirical model of radiation-induced interface states at the SiO2/Si interface in SiO2 MOS capacitors is developed. The formulation explicitly addresses the time-dependent two stage nature of the buildup process, and it gives the mathematical dependencies of the experimentally observed buildup on time, field, temperature, and dose. The model is applied to both wet and dry grown oxides. The implications of the empirical model for microscopic mechanisms involved in the buildup are discussed. In particular, it is argued that the experimental observations can best be understood in terms of a positive ion (probably H+) release in the SiO2 bulk and the subsequent transport of the liberated ions to the SiO2/Si interface (for positive gate bias). The induced interface states result from an interaction of the ions at the interface.

Rechargeable magnesium and calcium metal batteries (RMBs and RCBs) are promising alternatives to lithium-ion batteries because of the high crustal abundance and capacity of magnesium and calcium. Yet, they are plagued by sluggish kinetics and parasitic reactions. We found a family of methoxyethyl-amine chelants that greatly promote interfacial charge transfer kinetics and suppress side reactions on both the cathode and metal anode through solvation sheath reorganization, thus enabling stable and highly reversible cycling of the RMB and RCB full cells with energy densities of 412 and 471 watt-hours per kilogram, respectively. This work provides a versatile electrolyte design strategy for divalent metal batteries.

This article presents the design procedures and average run lengths for two mulativariater cumulative sum (CUSUM) quality-control procedures. The first CUSUM procedure reduces each multivariate observation to a scalar and then forms a CUSUM of the scalars. The second CUSUM procedure forms a CUSUM vector directly from the observations. These two procedures are compared with each other and with the multivariate Shewhart chart. Other multivariate quality-control procedures are mentioned. Robustness, the fast initial response feature for CUSUM schemes, and combined Shewhart-CUSUM schemes are discussed.

The theory of a Bloch electron moving in the presence of a homogeneous electric field is reviewed and objections to the conventional derivations are discussed. A new derivation of the time development of a Bloch electron moving in a homogeneous, but time-dependent, electric field is presented using a vector potential to describe the field rather than the usual scalar potential. This new treatment avoids all the basic assumptions of the conventional derivations and demonstrates that a Bloch electron will oscillate in a single band with the Bloch period if a homogeneous electric field is abruptly turned on, with a tunneling probability into other bands given by the conventional expression. It is also shown that the calculated optical absorption will have the same ladderlike structure that would be obtained if Wannier-Stark quantized energy levels are assumed, although the present calculation makes no such assumption. The previous objections to the existence of Bloch oscillations for electrons in a perfect periodic potential are examined and found to be irrelevant provided the tunneling probability per Bloch oscillation period is much less than one, a condition that is generally satisfied for typical elemental and compound semiconductors for electric fields smaller than ${10}^{6}$ V/cm.

The operation, design and control of an isolated bidirectional DC–DC converter for hybrid electric vehicle energy management applications are discussed. Different operation modes and boundary conditions are distinguished by phase-shift angle and load conditions. The absolute and relative output voltage ripple was derived. The dead-band effect and safe operational area are further investigated. The relations between output power and leakage inductance and switching frequency are also presented. The proposed converter was simulated and a prototype was built and tested. Experiments on the converter's steady state and transient operations validated the design and simulation.

OBJECTIVES: To determine the effect of acutely increased intra-abdominal pressure on pleural pressure, intracranial pressure, and cerebral perfusion pressure, and to clarify the relationship between these parameters. DESIGN: Nonrandomized, controlled study. SETTING: Laboratory at a university medical center. SUBJECTS: Yorkshire swine, weighing 15 to 20 kg. INTERVENTIONS: Anesthetized, ventilated swine had a balloon inserted into the peritoneal cavity and catheters placed for measurement of intracranial pressure, pleural pressure, central venous pressure, pulmonary artery occlusion pressure, and mean arterial pressure. Following baseline measurements, intra-abdominal pressure was increased by incrementally inflating the intraperitoneal balloon. All parameters were remeasured 30 mins after each increase in intra-abdominal pressure. Two groups were studied: a) group 1 (n = 9) animals had intra-abdominal pressure increased to 25 mm Hg above baseline, then released; b) group 2 (n = 3) animals underwent sternotomy and pleuropericardotomy to prevent an increase in pleural pressure with increasing intra-abdominal pressure. MEASUREMENTS AND MAIN RESULTS: Increase of intra-abdominal pressure to 25 mm Hg above baseline caused significant (p < .05) increases in intracranial pressure (7.3 +/- 0.6 [SEM] to 16.4 +/- 1.9 mm Hg), pleural pressure (4.3 +/- 1.3 to 11.8 +/- 1.9 mm Hg), pulmonary artery occlusion pressure (9.0 +/- 0.6 to 14.3 +/- 0.8 mm Hg), and central venous pressure (6.6 +/- 0.7 to 10.7 +/- 0.9 mm Hg). The cardiac index (3.4 +/- 0.3 to 1.6 +/- 0.1 L/min/m2) and cerebral perfusion pressure (75.6 +/- 3.6 to 62.0 +/- 6.8 mm Hg) deceased significantly (p < .05), whereas mean arterial pressure (82.8 +/- 3.2 to 78.4 +/- 6.6 mm Hg) remained essentially constant. Sternotomy and pleuro-pericardotomy negated all effects of increased intra-abdominal pressure except the decreased cardiac index (1.6 +/- 0.1 to 2.5 +/- 0.2 L/min/m2). CONCLUSIONS: Acutely increased intra-abdominal pressure causes a significant increase in intracranial pressure and a decrease in cerebral perfusion pressure. Increased intra-abdominal pressure appears to produce this effect by augmenting pleural and other intrathoracic pressures and causing a functional obstruction to cerebral venous outflow via the jugular venous system. It is possible that the same phenomenon may be why persons with chronically increased intra-abdominal pressure, such as the morbidly obese, suffer from a high frequency rate of idiopathic intracranial hypertension.

Organoids-cellular aggregates derived from stem or progenitor cells that recapitulate organ function in miniature-are of growing interest in developmental biology and medicine. Organoids have been developed for organs and tissues such as the liver, gut, brain, and pancreas; they are used as organ surrogates to study a wide range of questions in basic and developmental biology, genetic disorders, and therapies. However, many organoids reported to date have been cultured in Matrigel, which is prepared from the secretion of Engelbreth-Holm-Swarm mouse sarcoma cells; Matrigel is complex and poorly defined. This complexity makes it difficult to elucidate Matrigel-specific factors governing organoid development. In this review, we discuss promising Matrigel-free methods for the generation and maintenance of organoids that use decellularized extracellular matrix (ECM), synthetic hydrogels, or gel-forming recombinant proteins.

The oxygen evolution reaction (OER) is the essential module in energy conversion and storage devices such as electrolyzer, rechargeable metal-air batteries and regenerative fuel cells. The adsorption energy scaling relations between the reaction intermediates, however, impose a large intrinsic overpotential and sluggish reaction kinetics on OER catalysts. Developing advanced electrocatalysts with high activity and stability based on non-noble metal materials is still a grand challenge. Central to the rational design of novel and high-efficiency catalysts is the development and understanding of quantitative structure-activity relationships, which correlate the catalytic activities with structural and electronic descriptors. This paper comprehensively reviews the benchmark descriptors for OER electrolysis, aiming to give an in-depth understanding on the origins of the electrocatalytic activity of the OER and further contribute to building the theory of electrocatalysis. Meanwhile, the cutting-edge research frontiers for proposing new OER paradigms and crucial strategies to circumvent the scaling relationship are also summarized. Challenges, opportunities and perspectives are discussed, intending to shed some light on the rational design concepts and advance the development of more efficient catalysts for enhancing OER performance.

We report the realization and properties of a high-resolution solid-state self-emissive microdisplay based on III-nitride semiconductor micro-size light emitting diodes (µLEDs) capable of delivering video graphics images. The luminance level of III-nitride microdisplays is several orders of magnitude higher than those of liquid crystal and organic-LED displays. The pixel emission intensity was almost constant over an operational temperature range from 100 to −100 °C. The outstanding performance is a direct attribute of III-nitride semiconductors. An energy efficient active drive scheme is accomplished by hybrid integration between µLED arrays and Si CMOS (complementary metal–oxide–semiconductor) active matrix integrated circuits. These integrated devices could play important roles in emerging fields such as biophotonics and optogenetics, as well as ultra-portable products such as next generation pico-projectors.

Abstract Water‐in‐salt (WiS) electrolytes provide a new pathway to widen the electrochemical window of aqueous electrolytes. However, their formulation strongly depends on the solubility of the chosen salts, imposing a stringent restriction on the number of possible WiS systems. This issue becomes more severe for aqueous Na‐ion batteries (ANIBs) owing to the relatively lower solubility of sodium salts compared to its alkaline cousins (Li, K, and Cs). A new class of the inert‐cation‐assisted WiS (IC‐WiS) electrolytes containing the tetraethylammonium (TEA + ) inert cation is reported. The Na IC‐WiS electrolyte at a superhigh concentration of 31 mol kg –1 exhibits a wide electrochemical window of 3.3 V, suppresses transition metal dissolution from the cathode, and ensures singular intercalation of Na into both cathode and anode electrodes during cycling, which is often problematic in mixed alkali cation systems such as K–Na and Li–Na. Owing to these unique advantages of the IC‐WiS electrolyte, the NaTiOPO 4 anode and Prussian blue analog Na 1.88 Mn[Fe(CN) 6 ] 0.97 ·1.35H 2 O cathode can be coupled to construct a full ANIB, delivering an average voltage of 1.74 V and a high energy density of 71 Wh kg −1 with a capacity retention of 90% after 200 cycles at 0.25C and of 76% over 800 cycles at 1C.

Optical absorption and fluorescence spectra of the non-Kramers ions Pr3+, Tb3+, and Ho3+ in the C2 sites of Y2O3 are reported. A crystal-field analysis of these data and previously reported data for Eu3+ and Tm3+ is performed that is based on a Hamiltonian of C2 point-group symmetry, including J-mixing effects. A best-fit analysis is performed for all five ions; resulting rms deviations between calculated and experimental levels range from 2.8 to 26.4 cm−1. Results of this analysis and of our previous analysis of Kramers ions in C2 sites are used to obtain a set of phenomenological crystal-field components Akm for the C2 sites. We predict the crystal-field splittings for Pm3+ in Y2O3, and we compare our previous prediction of the splittings of Gd3+ in Y2O3 with recently reported measurements. We also describe an effective point-charge model for the Y2O3 lattice in which good agreement between calculated and phenomenological Akm is obtained with qY1 = 2.53, qY2 = 1.26, and q0 = −1.052. (The quantities qY1, qY2, and q0, are, respectively, the charges on the C3i yttrium site, the C2 yttrium site, and the oxygen site, in units of e.) With this model, we calculate Akm for the C3i sites.

Lithium ion batteries should always be prevented from overheating and, hence, thermal monitoring is indispensable. Since only the surface temperature of the battery can be measured, a thermal model is needed to estimate the core temperature of the battery, which can be higher and more critical. In this paper, an online parameter identification scheme is designed for a cylindrical lithium ion battery. An adaptive observer of the core temperature is then designed based on the online parameterization methodology and the surface temperature measurement. A battery thermal model with constant internal resistance is explored first. The identification algorithm and the adaptive observer is validated with experiments on a 2.3Ah 26650 lithium iron phosphate/graphite battery. The methodology is later extended to address temperature-dependent internal resistance with nonuniform forgetting factors. The ability of the methodology to track the long-term variation of the internal resistance is beneficial for battery health monitoring.

Optical absorption and fluorescence spectra of the Kramers ions Ce3+, Sm3+, Dy3+, and Yb3+ in the C2 sites of Y2O3 are reported. A crystal-field analysis of these data and previously reported data for Nd3+ and Er3+ is performed that is based on a Hamiltonian of C2 point-group symmetry, including J-mixing effects. A best-fit analysis is performed for the ions Nd3+, Sm3+, Dy3+, and Er3+; resulting rms deviations between calculated and experimental levels range from 5.1 to 7.9 cm−1. Results of this analysis are used to obtain a smoothed set of crystal-field parameters for the entire lanthanide series; these smoothed parameters are used to predict the energy levels of Ce3+, Yb3+, and Gd3+ in Y2O3. Predictions for Ce3+ and Yb3+ are compared with experimental data.