现代IT企业活动中项目和过程方法的融合

如今在现代企业中存在着两个流行的观点项目作为业务运营的主要形式,项目作为企业变革的实现形式.相应地,企业可以划分为项目导向型的(核心业务以客户项目形式运营)和非项目导向型的(把项目主要作为内部发展的工具).然而这种划分是相对临时的,因为为了提高运营的效率,企业将自然地想到用项目代替日常流程(不幸的是经常在人为的方式下).反之一样,为提高项目的效率,企业想到他们的项目是一个常规的、重复的过程,可以被标准化,尽管每个单独的项目有自身独特的目标和环境.本文着眼于分析在IT企业的组织中流程和项目方法的结合的机会和融合的实践方法.     

Synthesis and exploration of multi-level,multi-perspective architectures of automotive embedded systems

Software and Systems Modeling - In industry, evaluating candidate architectures for automotive embedded systems is routinely done during the design process. Today’s engineers, however, are...     

Impact of the Spectral Composition of Kilovoltage X-rays on High-Z Nanoparticle-Assisted Dose Enhancement

Nanoparticles (NPs) with a high atomic number (Z) are promising radiosensitizers for cancer therapy. However, the dependence of their efficacy on irradiation conditions is still unclear. In the present work, 11 different metal and metal oxide NPs (from Cu (Z_Cu = 29) to Bi₂O₃ (Z_Bi = 83)) were studied in terms of their ability to enhance the absorbed dose in combination with 237 X-ray spectra generated at a 30–300 kVp voltage using various filtration systems and anode materials. Among the studied high-Z NP materials, gold was the absolute leader by a dose enhancement factor (DEF; up to 2.51), while HfO₂ and Ta₂O₅ were the most versatile because of the largest high-DEF region in coordinates U (voltage) and E_eff (effective energy). Several impacts of the X-ray spectral composition have been noted, as follows: (1) there are radiation sources that correspond to extremely low DEFs for all of the studied NPs, (2) NPs with a lower Z in some cases can equal or overcome by the DEF value the high-Z NPs, and (3) the change in the X-ray spectrum caused by a beam passing through the matter can significantly affect the DEF. All of these findings indicate the important role of carefully planning radiation exposure in the presence of high-Z NPs.     

Shape Persistent,Highly Conductive Ionogels from Ionic Liquids Reinforced with Cellulose Nanocrystal Network

Shape-persistent, conductive ionogels where both mechanical strength and ionic conductivity are enhanced are developed using multiphase materials composed of cellulose nanocrystals and hyperbranched polymeric ionic liquids (PILs) as a mechanically strong supporting network matrix for ionic liquids with an interrupted ion-conducting pathway. The integration of needlelike nanocrystals and PIL promotes the formation of multiple hydrogen bonding and electrostatic ionic interaction capacitance, resulting in the formation of interconnected networks capable of confining a high amount of ionic liquid (≈95 wt%) without losing its self-sustained shape. The resulting nanoporous and robust ionogels possess outstanding mechanical strength with a high compressive elastic modulus (≈5.6 MPa), comparable to that of tough, rubbery materials. Surprisingly, these rigid materials preserve the high ionic conductivity of original ionic liquids (≈7.8 mS cm⁻¹), which are distributed within and supported by the nanocrystal network-like rigid frame. On the one hand, such stable materials possess superior ionic conductivities in comparison to traditional solid electrolytes; on the other hand, the high compression resistance and shape-persistence allow for easy handling in comparison to traditional fluidic electrolytes. The synergistic enhancement in ion transport and solid-like mechanical properties afforded by these ionogel materials make them intriguing candidates for sustainable electrodeless energy storage and harvesting matrices.     

Cytokine Profiling in Different SARS-CoV-2 Genetic Variants

This study is a successor of our previous work concerning changes in the chemokine profile in infection that are associated with different SARS-CoV-2 genetic variants. The goal of our study was to take into account both the virus and the host immune system by assessing concentrations of cytokines in patients infected with different SARS-CoV-2 variants (ancestral Wuhan strain, Alpha, Delta and Omicron). Our study was performed on 340 biological samples taken from COVID-19 patients and healthy donors in the timespan between May 2020 and April 2022. We performed genotyping of the virus in nasopharyngeal swabs, which was followed by assessment of cytokines’ concentration in blood plasma. We noted that out of nearly 30 cytokines, only four showed stable elevation independently of the variant (IL-6, IL-10, IL-18 and IL-27), and we believe them to be ‘constant’ markers for COVID-19 infection. Cytokines that were studied as potential biomarkers lose their diagnostic value as the virus evolves, and the specter of potential targets for predictive models is narrowing. So far, only four cytokines (IL-6, IL-10, IL-18, and IL-27) showed a consistent rise in concentrations independently of the genetic variant of the virus. Although we believe our findings to be of scientific interest, we still consider them inconclusive; further investigation and comparison of immune responses to different variants of SARS-CoV-2 is required.     

Annealing effects on microstructure and mechanical properties of sputtered multilayer Cr(1 − x)AlxN films

Multilayer Cr_(1 − x)Al_xN films with a total thickness of 2 μm were deposited on high-speed steel by medium frequency magnetron sputtering from Cr and Al-Cr (70 at.% Al) targets. The samples were annealed in air at 400 °C, 600 °C, 800 °C and 1000 °C for 1 hour. Films were characterized by cross-sectional scanning electron microscopy and X-ray diffraction analysis. The grain size of the as-deposited multilayer films is about 10 nm, increasing with the annealing temperature up to 100 nm. Interfacial reactions have clearly changed at elevated annealing temperatures. As-deposited films' hardness measured by nanoindentation is 22.6 GPa, which increases to 26.7 GPa when the annealing temperature goes up to 400 and 600 °C, but hardness decreases to 21.2 GPa with further annealing temperature increase from 600 to 1000 °C. The multilayer film adhesion was measured by means of the scratch test combined with acoustic emission for detecting the fracture load. The critical normal load decreased from 49.7 N for the as-deposited films to 21.2 N for the films annealed at 1000 °C.     

The dependence of complex alloyed steel properties on quenching and tempering conditions

M.P. Braun 's school in the Scientific-Research Institute of Casting Problems, Ukrainian Academy of Sciences, the Ukraine, investigated the structure and properties of complex alloyed steels for many years, focusing on carbide formation and phase transformations. My son, Alexandr Vinokur, prior to his death, was working in the Scientific-Research E.O. Paton Institute of Electrical Welding,Ukrainian Academy of Science, the Ukraine, as a researcher. This article is a result of our collaboration and his input is invaluable.     

Sol-Gel Synthesis of High-Quality Heavy-Metal Fluoride Glasses

Fluoride glasses are excellent laser hosts and are very well suited for a broad spectrum of optical applications. However, current fluoride glass synthesis is expensive. The solgel method is an affordable alternative for producing highperformance, optical-quality heavy-metal fluoride glasses. The method involves forming a hydrous oxide gel of the constituent metal alkoxides and salts, polymerizing the solution to form a gel, fluorinating the gel with anhydrous HF, melting the amorphous material in an oxidizing atmosphere of SF₆, and casting the melt into desired shapes. ZBLA (57ZrF₄·36BaF₂·4LaF₃·3AlF₃, in mol%) and Nd-doped (0.3 mol%) ZBLA glass rods were prepared by this process and their properties were measured. The solgel-based glasses had thermal and optical properties similar to those found in the literature for conventionally prepared fluorides.     

Experimental and numerical studies of void fraction distribution in rectangular bubble columns

Bubbly flow is encountered in a wide variety of industrial applications ranging from flows in nuclear reactors to process flows in chemical reactors. The presence of a second phase, recirculating flow, instabilities of the gas plume and turbulence, complicate the hydrodynamics of bubble column reactors.This paper describes experimental and numerical results obtained in a rectangular bubble column 0.1 m wide and 0.02 m in depth. The bubble column was operated in the dispersed bubbly flow regime with gas superficial velocities up to 0.02 m/s. Images obtained from a high speed camera were used to observe the general flow pattern and have been processed to calculate bubble velocities, bubble turbulence parameters and bubble size distributions. Gas disengagement technique was used to obtain the volume averaged gas fraction over a range of superficial gas velocities. A wire mesh sensor was applied, to measure the local volume fraction at two different height positions. Numerical calculations were performed with an Eulerian–Eulerian two-fluid model approach using the commercial code CFX.The paper details the effect of various two-fluid model interfacial momentum transfer terms on the numerical results. The inclusion of a lift force was found to be necessary to obtain a global circulation pattern and local void distribution that was consistent with the experimental measurements. The nature of the drag force formulation was found to have significant effect on the quantitative volume averaged void fraction predictions.