Methods for assessing the technical compatibility of heterogeneous elements within a technical system

The article provides methods for assessing the compatibility of elements in the design of complex technical systems. The compatibility of the elements is considered as the main indicator that determines the quality of systems including heterogeneous elements. The presented methods make it possible at the design stage to choose a technical solution that is most suitable for the project objectives, taking into account the operating conditions of the system. The methods make it possible to evaluate compatibility by a single and complex indicator. The choice of indicator depends on the purpose of the assessment. An example of methods implementation in the design of systems including an electric drive and pipeline shutoff valves is considered. It has been experimentally proved that in systems with low values ​​of the compatibility level, the actual power characteristics exceed the required values, which leads to additional voltages in the system elements and their breakdowns. The results of the assessment of typical systems allowed to identify the shortcomings of existing structures and propose alternative solutions to problems. The compatibility of elements within the framework of a technical system makes it possible to increase the functional efficiency of systems with minimum weight and size and power characteristics, to optimize the price-quality ratio, and to increase the competitiveness of the final product

Admittance of MIS structures based on graded-gap MBE HgCdTe with Al2O3 insulator

The paper presents the results of studies of the admittance of MIS structures based on heteroepitaxial MBE n (p)-Hg0.78Cd0.22Te with insulator coating SiO2/Si3N4 and Al2O3 in the test signal frequency range 10 kHz-1 MHz at temperatures ranging from 8 to 220 K. The main parameters of MIS structures with different insulators were determined. MIS structures with Al2O3 have a large enough insulator capacitance (compared to SiO2/Si3N4), a significant modulation capacitance on the CV characteristics, high dielectric strength and low values of the flat-band voltage. The effective charge density found from the value of the flat-band voltage and slow interface trap density for structures with Al2O3 comparable with the corresponding densities for structures with SiO2/Si3N4

Impact of the graded-gap layer on the admittance of MIS structures based on MBE-grown n-Hg1-xCdxTe (x = 0.22-0.23) with the Al2O3 insulator

The impact of the presence of the near-surface graded-gap layers with an increased content of CdTe on the admittance of MIS structures based on MBE-grown n-Hg1–xCdxTe (x = 0.22–0.23) with the Al2O3 insulating coating has been experimentally studied. It has been shown that the structures with a gradedgap layer are characterized by a deeper and wider capacitance dip in the low-frequency capacitance–voltage (CV) characteristic and by higher values of the differential resistance of the space-charge region than the structures without such a layer. It has been found that the main features of the hysteresis of capacitance dependences typical of the graded-gap structures with SiO2/Si3N4 are also characteristic of the MIS structures with the Al2O3 insulator. The factors that cause an increase in the CV characteristic hysteresis upon formation of the graded-gap layer in structures with SiO2/Si3N4 or Al2O3 are still debatable, although it may be assumed that oxygen plays a certain role in formation of this hysteresis

Трансформация функционально-потоковых параллельных программ в императивные

Functional dataflow programming languages are designed to create parallel portable programs. The source code of such programs is translated into a set of graphs that reflect information and control dependencies. The main way of their execution is interpretation, which does not allow to perform calculations efficiently on real parallel computing systems and leads to poor performance. To run programs directly on existing computing systems, you need to use specific optimization and transformation methods that take into account the features of both the programming language and the architecture of the system. Currently, the most common is the Von Neumann architecture, however, parallel programming for it in most cases is carried out using imperative languages with a static type system. For different architectures of parallel computing systems, there are various approaches to writing parallel programs. The transformation of dataflow parallel programs into imperative programs allows to form a framework of imperative code fragments that directly display sequential calculations. In the future, this framework can be adapted to a specific parallel architecture. The paper considers an approach to performing this type of transformation, which consists in allocating fragments of dataflow parallel programs as templates, which are subsequently replaced by equivalent fragments of imperative languages. The proposed transformation methods allow generating program code, to which various optimizing transformations can be applied in the future, including parallelization taking into account the target architecture.Функционально-потоковая парадигма параллельного программирования ориентирована на разработку параллельных переносимых программ. Исходный код функционально-потоковых программ транслируется в набор графов, отражающих информационные и управляющие зависимости. Основным способом их исполнения является интерпретация, что не позволяет эффективно выполнять вычисления на реальных параллельных вычислительных системах и ведет к низкой производительности. Для непосредственного выполнения программ на существующих вычислительных системах требуется использование специфических методов оптимизации и трансформации, учитывающих особенности как языка программирования, так и архитектуры исполнителя. В настоящее время наиболее распространенной является архитектура Фон-Неймана, параллельное программирование для которой в большинстве случаев осуществляется с использованием языков, поддерживающих императивный стиль и ориентированных на статическую систему типов. Для различных архитектур параллельных вычислительных систем существуют разнообразные подходы к написанию параллельных программ. Трансформация функционально-потоковых параллельных программ в императивные позволяет сформировать общий каркас из фрагментов императивного кода, непосредственно отображающих последовательные вычисления, который в дальнейшем может быть адаптирован к конкретной параллельной архитектуре. В работе рассматривается подход к выполнению такого типа трансформации, заключающийся в выделении фрагментов функционально-потоковых параллельных программ в качестве шаблонов, заменяемых впоследствии на эквивалентные фрагменты императивных языков. Предлагаемые методы трансформации позволяют порождать программный код, к которому в дальнейшем можно применять различные оптимизирующие преобразования, включая распараллеливание с учетом целевой архитектуры

Efficiency of Finding Muon Track Trigger Primitives in CMS Cathode Strip Chambers

In the CMS Experiment, muon detection in the forward direction is accomplished by cathode strip chambers~(CSC). These detectors identify muons, provide a fast muon trigger, and give a precise measurement of the muon trajectory. There are 468 six-plane CSCs in the system. The efficiency of finding muon trigger primitives (muon track segments) was studied using~36 CMS CSCs and cosmic ray muons during the Magnet Test and Cosmic Challenge~(MTCC) exercise conducted by the~CMS experiment in~2006. In contrast to earlier studies that used muon beams to illuminate a very small chamber area ($< \! 0.01$~m$^2$), results presented in this paper were obtained by many installed CSCs operating {\em in situ} over an area of $\approx \! 23$~m$^2$ as a part of the~CMS experiment. The efficiency of finding 2-dimensional trigger primitives within 6-layer chambers was found to be~$99.93 \pm 0.03\%$. These segments, found by the CSC electronics within $800$~ns after the passing of a muon through the chambers, are the input information for the Level-1 muon trigger and, also, are a necessary condition for chambers to be read out by the Data Acquisition System

Outcomes of elective liver surgery worldwide: a global, prospective, multicenter, cross-sectional study

Background: The outcomes of liver surgery worldwide remain unknown. The true population-based outcomes are likely different to those vastly reported that reflect the activity of highly specialized academic centers. The aim of this study was to measure the true worldwide practice of liver surgery and associated outcomes by recruiting from centers across the globe. The geographic distribution of liver surgery activity and complexity was also evaluated to further understand variations in outcomes. Methods: LiverGroup.org was an international, prospective, multicenter, cross-sectional study following the Global Surgery Collaborative Snapshot Research approach with a 3-month prospective, consecutive patient enrollment within January–December 2019. Each patient was followed up for 90 days postoperatively. All patients undergoing liver surgery at their respective centers were eligible for study inclusion. Basic demographics, patient and operation characteristics were collected. Morbidity was recorded according to the Clavien–Dindo Classification of Surgical Complications. Country-based and hospital-based data were collected, including the Human Development Index (HDI). (NCT03768141). Results: A total of 2159 patients were included from six continents. Surgery was performed for cancer in 1785 (83%) patients. Of all patients, 912 (42%) experienced a postoperative complication of any severity, while the major complication rate was 16% (341/2159). The overall 90-day mortality rate after liver surgery was 3.8% (82/2,159). The overall failure to rescue rate was 11% (82/ 722) ranging from 5 to 35% among the higher and lower HDI groups, respectively. Conclusions: This is the first to our knowledge global surgery study specifically designed and conducted for specialized liver surgery. The authors identified failure to rescue as a significant potentially modifiable factor for mortality after liver surgery, mostly related to lower Human Development Index countries. Members of the LiverGroup.org network could now work together to develop quality improvement collaboratives

Modification of Nanocrystalline Porous Cu2-xSe Films during Argon Plasma Treatment

Cu2-xSe films were deposited on Corning glass substrates by radio frequency (RF) magnetron sputtering and annealed at 300 &deg;C for 20 min under N2 gas ambient. The films had a thickness of 850&ndash;870 nm and a chemical composition of Cu1.75Se. The initial structure of the films was nanocrystalline with a complex architecture and pores. The investigated films were plasma treated with RF (13.56 MHz) high-density low-pressure inductively coupled argon plasma. The plasma treatment was conducted at average ion energies of 25 and 200 eV for durations of 30, 60, and 90 s. Notably, changes are evident in the surface morphology, and the chemical composition of the films changed from x = 0.25 to x = 0.10 to x = 0.00, respectively, after plasma treatment at average ion energies of 25 and 200 eV, respectively

Modification of Nanocrystalline Porous Cu_2-xSe Films during Argon Plasma Treatment

Cu2-xSe films were deposited on Corning glass substrates by radio frequency (RF) magnetron sputtering and annealed at 300 °C for 20 min under N2 gas ambient. The films had a thickness of 850–870 nm and a chemical composition of Cu1.75Se. The initial structure of the films was nanocrystalline with a complex architecture and pores. The investigated films were plasma treated with RF (13.56 MHz) high-density low-pressure inductively coupled argon plasma. The plasma treatment was conducted at average ion energies of 25 and 200 eV for durations of 30, 60, and 90 s. Notably, changes are evident in the surface morphology, and the chemical composition of the films changed from x = 0.25 to x = 0.10 to x = 0.00, respectively, after plasma treatment at average ion energies of 25 and 200 eV, respectively

Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone dimethylformamide monosolvate

Compounds (I), C9H10N2O4, (II), C11H12N2O4, and (III), C14H12N2O4·C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone derivatives with very similar molecular geometries for the bicyclic framework: the dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)–(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C2v symmetry. The spiro-cyclopentane derivative (II) and the phenyl/methyl analog (III) retain only internal Cs symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) Å. In compound (III), an N—H...O hydrogen bond is formed with the dimethylformamide solvent molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N—H...O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-arranged O=C—N—H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N—H groups in hydrogen bonding with the solvent molecule. As a result, the molecules of (III) form zigzag chains rather than the ribbons through intermolecular N—H...O hydrogen bonds. The crystal of (I) was a pseudo-merohedral twin