KiDS0239-3211: A new gravitational quadruple lens candidate

We report the discovery of a candidate to quadrupole gravitationally lensed system KiDS0239-3211 based on the public data release 3 of the KiDS survey and machine learning techniques

Research model robot-hexapod under static and dynamic loads

In the paper the stress-strain state of hexapod robot is considered in order to clarify its dynamical characteristics. Full-size model of hexapod robot is built in the SolidWorks program complex. The state of the robot was analyzed in an extremely dangerous location at static loading. Dynamic analysis was conducted to clarify oscillation of the support unit in the robot’s construction. The results of the survey show that such robot design cannot be used in the environments with the vibrating background below 5 Hz

Modern Challenges for International Sea Freight

The article highlights the new realities in the international freight transportation emerged under the simultaneous challenges, related to the global economic crisis, climate change and the COVID-19 pandemic consequences. The authors argue that the seaborn trade has been encountering a fundamental disorders a long before the contemporary global shocks emergence. Additionally the global container crisis, caused by the shortage of free containers and its growing costs has made the whole situation in the international freight transportation worse, causing the delivery time extention and the growth of inflation. The article is aimed on the identification of the most challenging problems in theory and decision makings, encountering the international freight turnover. Analysing the breakthrough research, expertise and applying the new methodological findings the authors of the articleargue the prospective transformation of the international logistics and proposing new framing features for the global supply chaing configuration. The article states the most undermining processes for the international feight turnover such as the global economic crisis, from its beginning in 2008, the enforcement of the international trade contradictions, specifically US-China trade war, ecological degradation, climate change and the global supply chain disruption, enforced by the global container crisis. The unique role of China as the preconditioning chain in the global supply of the commodities, parts and assembiles was revealed as the most risky factor for the business and governments in all over the world. The article concludes that the global system of international seaborn freight transportation has been entering into the epoch of profound transformation. The foresighting about the main direction of that transformation could be meaningful for Russia and the elaboration of its national transportation strategy

Global Supply Chains: New Trends in the Context of the Coronavirus Pandemic

The article is dedicated to the new trends emerging in the global supply chain, related to the coronavirus pandemic COVID-19, substantially affected production, transportation and marketing of goods. The authors underline a high risks of initial chain location in China, which sporadically leads to a localization of production supply within national borders. This biase in the international logistics is rather long term than short term I terms of national sustainability. The authors underline the icreasing significance of risk reduction and supply chain reliability over minimization of cost in the logistical decision makings. The ambivalency in the trade of the pandemic emergency goods is analysed in a sense of providing specifically favourable terms for its sirculation among the countries on the one side and the national protection issued for such goods by the national governments, pursuing its sufficient provision on the domestic market on the other side

KiDS-SQuaD: The KiDS Strongly lensed Quasar Detection project

New methods have been recently developed to search for strong gravitational lenses, in particular lensed quasars, in wide-field imaging surveys. Here, we compare the performance of three different, morphology- and photometry- based methods to find lens candidates over the Kilo-Degree Survey (KiDS) DR3 footprint (440 deg$^2$). The three methods are: i) a multiplet detection in KiDS-DR3 and/or Gaia-DR1, ii) direct modeling of KiDS cutouts and iii) positional offsets between different surveys (KiDS-vs-Gaia, Gaia-vs-2MASS), with purpose-built astrometric recalibrations. The first benchmark for the methods has been set by the recovery of known lenses. We are able to recover seven out of ten known lenses and pairs of quasars observed in the KiDS DR3 footprint, or eight out of ten with improved selection criteria and looser colour pre-selection. This success rate reflects the combination of all methods together, which, taken individually, performed significantly worse (four lenses each). One movelty of our analysis is that the comparison of the performances of the different methods has revealed the pros and cons of the approaches and, most of all, the complementarities. We finally provide a list of high-grade candidates found by one or more methods, awaiting spectroscopic follow-up for confirmation. Of these, KiDS 1042+0023 is to our knowledge the first confirmed lensed quasar from KiDS, exhibiting two quasar spectra at the same source redshift at either sides of a red galaxy, with uniform flux-ratio $f\approx1.25$ over the wavelength range $0.45\mu\mathrm{m}<\lambda<0.75\mu\mathrm{m}.$Comment: 12 pages, 4 figures, 4 tables, accepted for publication in MNRA

The Possibility of Using Tyumen Keramzite Clay in the Production of Ceramic Materials

The properties of red low-melting clay with the aim of its use in the production of building ceramics are investigated. The presented sample of clay raw materials by mineral composition refers to kaolinite clays with mixed-layer formations in the form of illite and ferruginous montmorillonite with Na-, Ca- and Mg-interlayer hydrated exchange cations. It is characterized by an average content of free SiO2 (10 - 25%). The clay is medium plastic with a low content of coarse inclusions, it refers to medium raw materials. Clay is medium-drying, medium-sensitive to drying, non-sintering. Mechanical strength during firing at a temperature of 900 C is 27.5 MPa. When firing samples in the temperature range 900 - 1050 C, a significant black core is formed. At a firing temperature of 1050 C, swelling of the samples occurs. Considering the properties of this clay, it cannot be recommended to produce face and ordinary building bricks. However, the studied clay can be used to produce expanded clay. The introduction of 0.5% of spent technical oil allows to get the expansion coefficient of 3.83. The temperature range of expansion is 1050 - 1170 C. The density of expanded clay granules in this case is 560 kg•m-3. © Published under licence by IOP Publishing Ltd

Technogenic Raw Materials in High-Alumina Chamotte Production

The paper presents studies on the production of a high-alumina aggregate with an Al2O3 content of 75% based on fine-grained corundum dust generated by grinding fused corundum. Finely dispersed corundum powder is a by-product and due to the low Al2O3 content (93 - 95%) is not used in further production. It is proposed to obtain high-alumina aggregate without joint grinding of the components. Aggregate was obtained by pressing through a "false grain"from a mixture of kaolin and corundum dust in a certain ratio. The samples firing was carried out at a temperature of 1700 C. The phase composition of the obtained aggregate is represented by 46 - 51% corundum, 45 - 49% mullite. The water absorption of such chamotte is 14 - 16%, open porosity is 33 - 35%, apparent density is 2230 - 2290 kg•m-3. Now, it was not possible to obtain a high-density filler grade ZML and ZMK that meets the requirements of GOST 23037 - 78. The production flow chart of high-alumina chamotte based on kaolin and corundum dust should include a joint fine grinding of the components, or a separate grinding of corundum dust until it passes completely through the 0.063 mm mesh. © Published under licence by IOP Publishing Ltd

The use of technogenic raw materials to produce a high-alumina chamotte

When fused corundum is crushed, a finely dispersed powder is formed with an Al2O3 content of 93-95%, in the form of substandard material. It is advantageous to utilize this powder to obtain high-alumina chamotte with Al2O3 content of more than 62%. High-alumina aggregate (chamotte) was obtained by semi-dry technology with intermediate briquette molding from a mixture of corundum dispersed powder and enriched kaolin. Based on a final Al2O3 content of 65 wt. % the batch composition of the mass to produce a high alumina aggregate (chamotte) was calculated. From a mixture of dispersed corundum powder and kaolin moistened with a 5-7% technical lignosulfonate solution with a density of 1050 kg•m-3, a briquette was formed at a specific pressing pressure of 15-20 MPa. The briquette was fired at a temperature of 1700 C. The fired briquette had a strength of 164 to 193 MPa. The water absorption of briquettes was 11-12%. The phase composition of the briquette is represented mainly by corundum and mullite. The enriched kaolin did not show sintering effect on fine corundum. © Published under licence by IOP Publishing Ltd