1,771 research outputs found
Development of methodology of alternative rationale for financial ensuring of bridges building
The purpose of the article is to develop a methodology for alternative substantiation of financial support for bridge construction. To achieve the purpose, the following general scientific and special methods and techniques of research were used: “golden ratio” rule; systematization and generalization; generalization of the results of the analysis and the logical generation of conclusions. Initially, the article analyzed the state of bridge structures in Europe and Ukraine. Based on the analysis, a disappointing situation has been identified, namely that a significant ratio of bridges number require major overhaul or are in critical condition. During the research, the following tasks were solved, namely: physical wear of the bridge as a failure was considered; the feasibility of investing in reconstruction or new bridge construction was determined.
For the purpose of rational use of financial resources, which are limited in the age of economic challenges, and on the basis of the rule of “golden proportion”, the maximum percentage of investment in reconstruction is determined. If the limit is exceeded, it is decided to build a new bridge. This result allows making an economically sound decision and evaluating the effectiveness of the invested resources. It is proved that if the wear index of the overhaul bridge construction is higher than the wear rate of the new bridge construction by λ2 / λ1, and the amount of funds for overhaul reaches 70% of the funds needed to build a new one, it is better to build a new bridge
Investigation of a steady-state cylindrical magnetron discharge for plasma immersion treatment
Ion current distribution in a system with crossed magnetic and electrical fields for plasma immersion ion implantation has been investigated. It is found that the ion current to a target has a nonmonotonic behavior with bias voltage when a magnetic field is applied. For instance, the current density has a maximum of about 150 A/m2 at bias voltage of about 1 kV in the case of a magnetic field parallel to the target of about 0.035 T. These results are explained in terms of ionization by magnetized electrons in the E×BE×B system. Our findings suggest that the system with crossed fields can be used for intense plasma immersed processing. © 2003 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71124/2/JAPIAU-94-3-1408-1.pd
Deterministic nanoassembly: Neutral or plasma route?
It is shown that, owing to selective delivery of ionic and neutral building blocks directly from the ionized gas phase and via surface migration, plasma environments offer a better deal of deterministic synthesis of ordered nanoassemblies compared to thermal chemical vapor deposition. The results of hybrid Monte Carlo (gas phase) and adatom self-organization (surface) simulation suggest that higher aspect ratios and better size and pattern uniformity of carbon nanotip microemitters can be achieved via the plasma route.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87817/2/033109_1.pd
RESTORATION OF FORESTS IN THE TERRITORIES PASSED BY LARGE-FOREST FOREST FIRE IN THE CONDITIONS OF THE STATE ENTERPRISE «OVRUTSKE FORESTRY»
Topical issues of forest regeneration in the territories of the State Forest Fund of the Zhytomyr Regional Department of Forestry and Hunting, which were passed by large-scale forest fires, are substantiated. The processes of forest regeneration in the conditions of tracts of the State Enterprise «Ovruch Forestry» are analyzed, as well as organizational and ecological-forestry aspects are considered.The subject of the work is reforestation on fires, which were formed as a result of large-scale forest fires in 2018, 2020 in the forests of the State Enterprise «Ovruch Forestry». Particular attention in the research process was paid to the condition of areas after large-scale forest fires, as well as technological features of reforestation in areas that were passed by large-scale forest fires, including in terms of radioactively contaminated soils. Today, these aspects are becoming extremely important for the restoration of forests in the post-fire period on fires not only in the forest edatopes of the State Enterprise «Ovruch Forestry», but also in the forest ecosystems of the Zhytomyr Regional Department of Forestry and Hunting. All the above elements of reforestation have significant practical economic value for forestry enterprises, as the issue of reforestation of fires is quite relevant in their production activities. A significant degree of forest burnout as a result of large-scale forest fires in 2018, 2020 in the forest edatops of the State Enterprise «Ovruch Forestry» significantly affected not only the state of economic development, but also the strategic sustainable development and infrastructure of settlements located in areas of large-scale forest fires, as well as, unfortunately, human casualties from the local population. All this emphasizes the extreme relevance and prospects of research on reforestation and the impossibility of recurrence and spread to large areas of forest fires in the region of Ovruch-Slovenian ridge.The aim of the work is to study in detail the possibility of conducting operational reforestation measures in areas affected by the fire of large-scale forest fires in 2020 and to predict the possibility of preventing the recurrence and spread of forest fires in large forested areas and settlements located in the «Ovruch Forestry».The main methods of reforestation after large-scale forest fires in forest tracts of the State Enterprise «Ovruch Forestry» are calculation and analytical collection and processing of the results of the laid trial areas on forest fires in 2018, 2020 monitoring of the impact of various forest fires in the forest. period on fires of different degrees of burning of wood, shrub, grass vegetation and litter for the effectiveness of afforestation of large-scale fires in the forest edata of the State Enterprise «Ovruch Forestry», as well as route surveys of areas adjacent to the centers of large-scale forest fires determining the degree of thermal damage to stands from exposure to high temperatures, infrared irradiation of arriving and mature stands, analysis of the effectiveness of measures to localize and extinguish large-scale forest fires, including the use of aircraft of the SES of Ukraine. Determining the nature of the population of forest stands, which were weakened due to the direct impact of forest fires, but were not destroyed by fire, forest and coniferous rodent pests. This will make it possible in the next 10 years to predict possible outbreaks and spread of forest pests from weakened stands as a result of large-scale forest fires in 2020 in arriving and mature stands to determine the nature of drying and damage to various species of conifers and leaf-eating rodents.According to the results of the work it was established that forest fires of the State Forest Fund of Zhytomyr Regional Department of Forestry and Hunting and forest tracts of the State Enterprise «Ovruch Forestry» in particular should be restored by creating forest crops by planting after soil preparation taking into account the conditions of radioactive contamination -15 Ki/km2. It was found that most of the studied forest fires by the degree of burnout from the influence of combustion factors during the development of large-scale forest fires are suitable for reforestation without prior soil reclamation and reclamation measures, which will further effectively conduct forest reforestation after forest fires. in the conditions not only of the State Enterprise «Ovruch Forestry», but also in the area of Zhytomyr Polissya in particular.The scope of research is the forestry enterprises of the Zhytomyr Regional Department of Forestry and Hunting, forest tracts of the State Enterprise «Ovruch Forestry» in which appropriate measures were taken to preserve and protect forests from large-scale forest fires, as well as further prevent victims among pine, oak, aspen, birch, alder forest plantations from forest pests in the Polissya zone of Ukraine.The conclusions of the research are that the application of the proposed measures for reforestation after large-scale forest fires allows at the initial stage of forest formation after reforestation in edatopes C2-C3 of the State Enterprise «Ovruch Forestry» to create viable pine, pine, oak which is resistant to pests and diseases. The proposed methods of reforestation after large-scale forest fires make it possible to plant forests under different mixing schemes without additional reclamation and reclamation measures, including in conditions of radioactive contamination with a density of 10-15 Ki/km2, to implement measures for fire prevention in conditions of the Polissya zone of Zhytomyr region. Practical recommendations on the use of forest regeneration methods in the territories of the Zhytomyr Regional Department of Forestry and Hunting to prevent cases of rapid occurrence and rapid spread of large-scale forest fires. As a result of our research, we found that the most effective reforestation occurs after high-intensity forest fires, after which the combustion of a layer of above-ground forest combustible materials and subsequent loss of burnt trees creates favorable conditions for emergence and growth of seedlings. We have established a close link between reforestation in areas affected by large-scale forest fires with 45% burning of forest combustible materials and the duration of the period of post-pyrological impact, which is particularly clear after high-intensity forest fires, which were observed in 2018, 2020 territories of forest tracts of the State Enterprise «Ovruch Forestry». It is established that after low-intensity forest fires the process of formation of viable undergrowth in pines of types C2-C3 is stretched for a longer period. It is determined that reforestation in pine plantations of types C2-C3 after large-scale forest fires of high intensity is satisfactory. It is analyzed that reforestation after medium and low intensity fires in 55% of cases the amount of undergrowth is not enough for successful reforestation. It is proved that after fire restoration in the conditions of forest types C2-C3 of the State enterprise «Ovruch forestry» occurs without change of breeds. As a result of the conducted researches we proved that after fire reforestation in the territories affected by large-scale forest fires with application of the offered schemes of mixing of wood breeds will give the chance to carry out afforestation with survival of seedlings by 85-90% more effectively. The results of the research confirm the effectiveness of the proposed methods of reforestation of forest fires after large-scale forest fires and may be useful in addressing the urgency of reforestation measures in the affected forest tracts of the State Enterprise «Ovruch Forestry» and in the Zhytomyr Regional Department. hunting economy in particular
Microscopic ion fluxes in plasma-aided nanofabrication of ordered carbon nanotip structures
Three-dimensional topography of microscopic ion fluxes in the reactive hydrocarbon-based plasma-aided nanofabrication of ordered arrays of vertically aligned single-crystalline carbon nanotip microemitter structures is simulated by using a Monte Carlo technique. The individual ion trajectories are computed by integrating the ion equations of motion in the electrostatic field created by a biased nanostructured substrate. It is shown that the ion flux focusing onto carbon nanotips is more efficient under the conditions of low potential drop UsUs across the near-substrate plasma sheath. Under low-UsUs conditions, the ion current density onto the surface of individual nanotips is higher for higher-aspect-ratio nanotips and can exceed the mean ion current density onto the entire nanopattern in up to approximately five times. This effect becomes less pronounced with increasing the substrate bias, with the mean relative enhancement of the ion current density ξiξi not exceeding ∼ 1.7∼1.7. The value of ξiξi is higher in denser plasmas and behaves differently with the electron temperature TeTe depending on the substrate bias. When the substrate bias is low, ξiξi decreases with TeTe, with the opposite tendency under higher-UsUs conditions. The results are relevant to the plasma-enhanced chemical-vapor deposition of ordered large-area nanopatterns of vertically aligned carbon nanotips, nanofibers, and nanopyramidal microemitter structures for flat-panel display applications.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87355/2/064304_1.pd
Suppression of current fluctuations in a crossed E×BE×B field system for low-voltage plasma immersion treatment
Plasma transport in a hybrid dc vacuum arc plasma source for ion deposition and plasma immersion treatment is considered. It is found that external crossed electric and magnetic fields near the substrate can significantly reduce the relative amplitude of ion current fluctuations fI¯f at the substrate surface. In particular, fI¯f decreases with the applied magnetic field when the bias voltage exceeds 300 V300V, thus allowing one to reduce the deviations from the rated process parameters. This phenomenon can be attributed to an interaction between the metal-plasma jet from the arc source and the discharge plasma in the crossed fields.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87466/2/013301_1.pd
Plasma-Controlled Metal Catalyst Saturation and the Initial Stage of Carbon Nanostructure Array Growth
The kinetics of the nucleation and growth of carbon nanotube and nanocone arrays on Ni catalyst nanoparticles on a silicon surface exposed to a low-temperature plasma are investigated numerically, using a complex model that includes surface diffusion and ion motion equations. It is found that the degree of ionization of the carbon flux strongly affects the kinetics of nanotube and nanocone nucleation on partially saturated catalyst patterns. The use of highly ionized carbon flux allows formation of a nanotube array with a very narrow height distribution of half-width 7 nm. Similar results are obtained for carbon nanocone arrays, with an even narrower height distribution, using a highly ionized carbon flux. As the deposition time increases, nanostructure arrays develop without widening the height distribution when the flux ionization degree is high, in contrast to the fairly broad nanostructure height distributions obtained when the degree of ionization is low
Business communications
Communication problems not only every year arouse more and more interest among people of different ages, diffrent professions and education, but, above all, are a necessary component of the professional competence of specialists in all areas of their activity. In 1941, Fethullah Gülen, an Islamic scholar and Turkish public figure, said that "thanks to advances in communications and transport, one of the driving forces of globalization, the distances between countries and peoples are rapidly blurring". But during communication, a person commits many mistakes and stupidities. Foolishness is visible in those moments when a person should be silent, and he speaks, or when it is necessary to speak, and he is silent, - Zufar Fatkudinov said. The same thing happens in entrepreneurial communications. Business communications are a set of contacts in the business environment that each firm establishes and reproduces in the process of carrying out entrepreneurial actions, participation in business relations. Business communications are interfirm or intrafirm in nature. Business communications should be distinguished from ordinary communication. They represent ways of organizing the interaction of business entities with their intra-firm and inter-firm environment, during which all parties of the interaction strive to defend their interests in business. The materials of this book can be used in the study of the disciplines "Ethics of business relations", "Business communication", "Psychology of business communication", "Psychology of management" in higher and secondary educational institutions. The textbook is practically oriented: at the end of each chapter there are control questions and tasks, as well as literature for independent study
Polypeptide translocation by the AAA+ ClpXP protease machine
In the AAA+ ClpXP protease, ClpX uses repeated cycles of ATP hydrolysis to pull native proteins apart and to translocate the denatured polypeptide into ClpP for degradation. Here, we probe polypeptide features important for translocation. ClpXP degrades diverse synthetic peptide substrates despite major differences in side-chain chirality, size, and polarity. Moreover, translocation occurs without a peptide –NH and with 10 methylenes between successive peptide bonds. Pulling on homopolymeric tracts of glycine, proline, and lysine also allows efficient ClpXP degradation of a stably folded protein. Thus, minimal chemical features of a polypeptide chain are sufficient for translocation and protein unfolding by the ClpX machine. These results suggest that the translocation pore of ClpX is highly elastic, allowing interactions with a wide range of chemical groups, a feature likely to be shared by many AAA+ unfoldases.National Institutes of Health (U.S.) (AI-15706
Estimation of state financial support for non-priority territorial units using the example of bridge constructions
The article discloses the problem of distributing state financial support based on an integrated approach. The study has proved the urgency and necessity of state support for the lowest priority territorial units (regions). It answers the research question of what components need to be included in the methodology for determining state financial support. A comprehensive method for estimating the share of public funds is proposed, taking into account the investment attractiveness of a region (oblast) and the risk of the corresponding region (oblast). To achieve this goal, the following general scientific and special methods and research techniques were used in the work, such as comparative analysis of scientific literature and information sources based on methods of comparison, systematization, and generalization; generalization of the analysis results, as well as logical generation of conclusions and integral assessment.
Since the problem of financing the construction and reconstruction of bridges is relevant for a number of countries, this technique was tested using an example of bridge construction.
According to the obtained results, territorial units (regions) that are not leaders in priority for the investor and have a high level of riskiness of investing financial resources become eligible for state financial support. The problem of financing such regions can be solved only through state support. The results of calculations show that the distribution of financial resources with the available volume of public finances K=1 allocated for support is carried out proportionally. An integrated approach made it possible to identify 10 territorial units (oblasts) for funding, with the oblasts with the worst priority factors receiving the largest share of state financial support.
This study is of practical interest to government agencies in the distribution of public funds, and it is of theoretical importance to researchers dealing with issues of financial security and public administration
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