Optimum distance flag codes from spreads via perfect matchings in graphs

In this paper, we study flag codes on the vector space $${{\mathbb {F}}}_q^n$$ F q n , being q a prime power and $${{\mathbb {F}}}_q$$ F q the finite field of q elements. More precisely, we focus on flag codes that attain the maximum possible distance (optimum distance flag codes) and can be obtained from a spread of $${{\mathbb {F}}}_q^n$$ F q n . We characterize the set of admissible type vectors for this family of flag codes and also provide a construction of them based on well-known results about perfect matchings in graphs. This construction attains both the maximum distance for its type vector and the largest possible cardinality for that distance.

Bicycle center infrastructure in a city

The paper deals with the bicycle center infrastructure in a city, which becomes popular every year, but is not yet studied properly. Little attention is devoted to the spatial development for two-wheeled vehicles, so there are many problems to be discussed and solved.The purpose of this paper is to determine the types of bicycle centers in the structure of a city, from the main and central to regional and peripheral that connect all urban areas. Moving along the bicycle paths from home to a large bicycle center and back to home, one can communicate in bicycle centers. Less functional peripheral centers provide repair services, bicycle rental and small recreation. The city of Rostov-on-Don is taken as an example.The following parameters are determined: optimum distance between bicycle centers of different types, their functional content, bicycle center location in the city. In the future, it is possible to arrange such centers in any city due to their unification.The model of the bicycle center network is proposed for the city of Rostov-on-Don, that are characterized by different area and multifunctional purposes for each district to attract people. The main bicycle center includes sports grounds, bicycle track, rock climbers, skate park, gyms, ski jumping hall and other sports facilities. Roof-top bike trails, amphitheater with a street stage, art spaces, go-karting can be arranged on the territory of these centers.

The Optimum Distance of Lift-Off Height on Different Test Material’s Thickness by using Eddy Current Testing Technique

The Eddy current testing (ECT) technique is one of the non-destructive testing (NDT) techniques which is sensitive to the unintended signal such as lift-off (LO) height effect. The output voltage of signal defects with different thicknesses of test materials (i.e., Copper, Brass and Magnesium Alloy) can be determined from the optimum distance of LO height of the ECT technique. Previously, an established frequency was determined for these particular materials (i.e., Copper = (5.00-5.25) MHz, Brass = (4.75-5.25)MHz and Magnesium Alloy= (4.75-5.00)MHz). The frequency then generated the established voltage signal of the ECT technique. The acquired optimum distance of LO height for these materials is approximately 2mm. The findings from this established technique indicated that the determined optimum distance of LO height can find the output voltage signal of the defects as well as to detect the thicknesses.

E3Cs: A Research-Based Model for Effective Digital Learning for K-6 Schools

Due to the COVID-19 pandemic, teachers in Ontario were thrust into a new teaching situation at the end of the 20192020 school year for which few were prepared. To address the need for guidance in transitioning to distance teaching, we offer the e-3Cs model, a research-based framework with flexible elements essential for promoting optimum distance interactions for K12 learning, more specifically applied to younger learners (K6). Serving as a tool for designing age-appropriate digital instruction while honouring and caring for affective domain needs of students, the model provides the necessary support for teachers in the purposeful design of digital learning communities.

Design and analysis microstrip antenna with reflector to enhancement gain for wireless communication

In this paper is presented the good solution to enhancement gain by using physical plane plate reflector with optimum distance by a reflector was used with the antenna and using a sweep parameter for the distance at which the reflector was placed at (, we found the best distance is when selected the bandwidth is 28GHz where . The gain at the bandwidth in 28GHz was improved from (5.48, 6.78, and 7.83) dB to 11.53 dB, while the gain without a reflector is 7.1 dB. The simulation results were obtained using CST which was more consistent with the practical results.

Improving the economic efficiency of production biodieselfuel

In order to optimize the performance of transportation works for the transportation of raw materials for the production of biodiesel fuel, the article examines the technology when oil from oilseeds is obtained at the processing points where they are grown. The resulting oil is transported to a biodiesel production plant. The methodological bases for calculating the optimum distance from oilseed grain storage sites to a mechanized oil production point are presented. Possible ways of the efficiency improving of production of biofuel at the stage of the planning are presented. Methodical bases of calculation of distance to mechanized points for biofuel production are given. A formula for determining the optimum capacity of an item for the processing of oil seeds and for obtaining raw materials for the production of biofuels has been derived. It is established that optimum transportation distance of rape is 14,4 km, productivity of the rapeseed oil processing plant is 21280 tons/year and for 25% of the oil yield 5320 tons of biofuel raw materials can be obtained, when the total overhead costs are Zv = 360000 UAH / year; specific costs of transportation of raw materials сp = 2,6 UAH/ (тkm); yield of oilseed rape = 1 t / ha (100 t / km2); the density of the placement of fields a = 0.4. The developed method can be used to calculate the location, performance of points for the manufacture of briquettes or pellets. The direction of increasing the efficiency of biodiesel production at plants at the stage of their planning is to determine the optimal annual productivity of the plant, taking into account transport costs for the transportation of raw materials - oil. The optimum distance of transportation of oil and productivity of the plant for biodiesel production is established for the cost of transportation - 2.6 UAH / t • km, overhead costs 13000000 UAH, direct costs for the production of 1 ton of biodiesel fuel - 25000 UAH Therefore, the optimal distance of transportation of oil for the production of biofuels - 101 km, the capacity of the plant - 58923 tons. The dependence of the cost of production of biodiesel fuel on the distance of transportation of oil is calculated: for distance to plant 40 km – the cost of biofuel production – 25596 UAH/t, for 60 km – 25496 UAH /t, for 80 km – 25462 UAH /t, for 100 km – 25459 UAH /t, for 120 km – 25471 UAH /t, for 140 km – 25493 UAH /t. The proposed method provides an opportunity to determine the optimum productivity of the plant for the processing of organic raw materials into biofuels, taking into account the distance of its transportation at the design stage. Key words: biodiesel, economic efficiency, production optimization, direct costs, overhead costs.