Transfer of innovative technologies最新文献

{"title":"Investigation of the relationship between the strength limit and the long time fatigue of steel reinforcements of reinforced concrete structures","authors":"D. Chernyshev, Yulia Makarenko, T. Khomutetska, V. Makarenko","doi":"10.32347/tit2021.42.0201","DOIUrl":"https://doi.org/10.32347/tit2021.42.0201","url":null,"abstract":"The results of experimental studies have shown a strong effect of diffusion hydrogen on the static and cyclic parameters of crack resistance of reinforcing steel. It was found that with increasing flooding, especially when the hydrogen content exceeds 5 cm3/100g, both static strength and long-term strength (fatigue) decrease sharply. Moreover, these areas of hydrogen solution in reinforcing steel are characterized by a viscous nature of fracture, while for heavily flooded reinforcement (from 5 to 12 cm3/100g) is characterized by brittle fracture by the mechanism of microcracking in the hardened (martensite or troostite structure). The analysis of the obtained experimental results allowed to determine the optimal hydrogen content in the reinforcing steel (3…5 cm3/100g), the excess of which can cause a decrease in the crack resistance of the reinforcement during long-term operation, especially in corrosive environments. \u0000The mechanism of hydrogen influence on crack resistance of metal at static and alternating loading which consists in diffusion and dislocation movement of hydrogen in structure of a reinforcing core that as a result that causes strong flooding of steel and its embrittlement is offered. It is established that carbon and low-alloy sieves, which are characterized by ferritic-pearlitic and sorbitol structure provide high resistance, especially to long-term fatigue, and the transition to steels with a structure of martensite or tempered (transient structure of bainite) structure of bainite sharply reduces reinforcing steel, which makes it impossible to use in the manufacture of reinforcement involved in reinforced concrete structures designed for long-term operation (more than 50…60 years). Thus, the obtained diagram can be recommended to designers of reinforced concrete structures for hydraulic purposes, as it greatly facilitates the reasonable choice of reinforcement in the development of reinforced concrete structures for responsible and long-term use.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117125744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Project development and marketing in the global oil and gas industry – a constellation of stakeholders co-creating strategic value for the industry","authors":"Hiroshi Tanaka, S. Bushuyev","doi":"10.32347/tit2021.42.0301","DOIUrl":"https://doi.org/10.32347/tit2021.42.0301","url":null,"abstract":"Project development and marketing on large oil and gas projects (LOGPs) by engineering-procurement-construction (EPC) contractors respond to massive capital investment (CAPEX) undertakings by oil and gas industry owners and takes on multi-lateral interactions carried out by a dozen of actors proactively participating in the EPC contractors’ business ecosystem created to remain competitive toward owner companies, which form of project marketing is different from a straight forward contractor – owner interaction found in the other branches of contracting industry. Most of such interactions are based on strategic trust among the relevant members built over decades of heavy win-win transactions. \u0000This study has found the actors that compose the project development and marketing cycle in LOGPs, explored dominant logics of EPC contractor’s project development and marketing, and analysed how primary actors in LOGP development and implementation co-create strategic values for both the respective corporations, and sustainable overall industry growth.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125578263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One approach to the axisymmetric problem of impact of fine shells of the S.P. Timoshenko type on elastic half-space","authors":"V. Bogdanov","doi":"10.32347/tit2021.42.0302","DOIUrl":"https://doi.org/10.32347/tit2021.42.0302","url":null,"abstract":"Refined model of S.P. Timoshenko makes it possible to consider the shear and the inertia rotation of the transverse section of the shell. Disturbances spread in the shells of S.P. Timoshenko type with finite speed. Therefore, to study the dynamics of propagation of wave processes in the fine shells of S.P. Timoshenko type is an important aspect as well as it is important to investigate a wave processes of the impact, shock in elastic foundation in which a striker is penetrating. The method of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind and the convergence of this solution are well studied. Such approach has been successfully used for cases of the investigation of problems of the impact a hard bodies and an elastic fine shells of the Kirchhoff-Love type on elastic a half-space and a layer. In this paper an attempt is made to solve the axisymmetric problem of the impact of an elastic fine spheric shell of the S.P. Timoshenko type on an elastic half-space using the method of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind. It is shown that this approach is not acceptable for investigated in this paper axisymmetric problem. The discretization using the Gregory methods for numerical integration and Adams for solving the Cauchy problem of the reduced infinite system of Volterra equations of the second kind results in a poorly defined system of linear algebraic equations: as the size of reduction increases the determinant of such a system to aim at infinity. This technique does not allow to solve plane and axisymmetric problems of dynamics for fine shells of the S.P. Timoshenko type and elastic bodies. This shows the limitations of this approach and leads to the feasibility of developing other mathematical approaches and models. It should be noted that to calibrate the computational process in the elastoplastic formulation at the elastic stage, it is convenient and expedient to use the technique of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132325175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stabilization of the process of mechanized pulsed-arc welding","authors":"S. Maksimov, Anatoly Gavrilyuk, D.N. Krazhanovskyi","doi":"10.32347/tit2021.42.0202","DOIUrl":"https://doi.org/10.32347/tit2021.42.0202","url":null,"abstract":"The main disadvantage of the mechanized arc welding process in shielding gases with short circuits is the spatter during melting of the electrode metal and its transfer to the weld pool, which affects the productivity of the process, reducing it. Its elimination is possible through the implementation of the controlled transfer of molten electrode metal into the weld pool. The implementation of such a transfer and the control of the processes that take place in the arc gap to a large extent determine the conditions for the qualitative formation of the deposited metal, the stability of the process, the magnitude of the loss of electrode metal and the manufacturability of the processes of arc welding in shielding gases. At the present stage of development of welding technologies, controlled transfer of electrode metal is possible due to the pulsed nature of arc burning. In this case, one of the main methods for increasing the efficiency of the process is to limit the maximum value of the short circuit current by increasing the inductive resistance of the welding circuit. \u0000The research aimed to determine the effect of the rate of rising of the welding current during a short circuit on the stability of the welding arc. It was found that an increase in the current growth rate, starting from 1.23 kA/s to 50 kA/ s, leads to a decrease in the average duration of short circuits by at least 10 times. At the same time, the average frequency of short circuits increases by more than 2 times, from 36...38 s-1 to 80...86 s-1. The reason for this is the increase in the values of the electrodynamics’ Lorentz force, the action of which leads to the compression of the liquid metal bridge of the drop (pinch effect) due to an increase in the short circuit current. At the same time, there is a violation of the stability of the pulse process, and this is reflected in an increase in the average frequency of arc breaks by more than 30 times from 0.33 s-1 to 10 s-1. An increase in the energy parameters of the welding process led to a decrease in the average frequency of short circuits (2...3 times) and their average duration (2 times). The reason for this should be considered a change in the type of transfer of liquid metal – the welding process with short circuits has turned into a mixed process in which, along with short circuits, a droplet transfer of electrode metal is observed.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123481399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Arts in Soviet Architecture: stages of development, main directions, causes of their occurrence","authors":"Liudmyla Bachynska","doi":"10.32347/tit2021.42.0102","DOIUrl":"https://doi.org/10.32347/tit2021.42.0102","url":null,"abstract":"The history of the Soviet Union, its socio-economic, socio-political and socio-cultural life is unique in comparison with other countries. The USSR was created on the model of social development, expressed by European and Russian Utopian socialists and was grounded in the classics of Marxism-Leninism. So, the system of government, economic conditions and cultural activities of a society built on the hegemony of the proletariat was a long-running social experiment that conditioned the life of the Soviet people and influenced other countries as well. The experiment of a country with total state property envisaged that the party leadership assumed responsibility for defining all spheres of political life - both internal and interstate relations - and inevitably formed unified programs of cultural activity and social development, managed them, and financed and tightly controlled their implementation. The Soviet people, the so-called \"working masses\", were forced to live and act under uniform rules. Depending on the planning of the political, economic and social life of the party leadership throughout the existence of the USSR, the country went through several stages, which differed in the directions of forming an architectural and urban planning environment that had to meet the tasks of state and ideological character. Familiarizing yourself with this unique experience and finding the reasons for its formation is important for understanding the trends of social development in the twentieth century.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115904513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improvement of the calculation and experimental method of evaluation of carbonization of reinforced concrete structures of sewerage underground systems","authors":"M. Sukach, V. Chigarov, I. Chebotar","doi":"10.32347/tit2021.42.0203","DOIUrl":"https://doi.org/10.32347/tit2021.42.0203","url":null,"abstract":"Carbonization of concrete leads to a decrease in the alkalinity of concrete, an increase in the number of hydrogen ions in the pores, is one of the main factors that lead to corrosion of reinforcement, the formation of cracks and the subsequent reduction of load-bearing capacity of structures. The study of the depth of carbonization of concrete is to determine the pH of the pore liquid at different depths. There are devices with automatic maintenance of a given concentration of carbon dioxide, to determine the diffusion permeability of concrete to carbon dioxide, based on data on the rate of neutralization (carbonization) of concrete with carbon dioxide. Basically, this method is intended for use in the development of technology and design of concrete composition, providing long-term maintenance of structures in non-aggressive and aggressive gaseous environments, as chips are not prepared immediately before the test and after reaching the design age are placed in the installation with reagents for 7 days. But to determine the carbonization directly on the construction site or object often use the pH method, i.e. the indicator method of pH determination. To assess the concentration of hydrogen ions used acid-base indicators - organic substances – dyes, the color of which depends on the pH from the obtained results the algorithm of definition of depth of carbonization consists in the following actions. The improved formula of definition of depth of carbonization of concrete taking into account degree of aging and corrosion damages for what in the final formula the corresponding coefficients kst and kkor are entered: hcarb = {(2D˖C˖τ) / (mo˖kst ˖kkor)} 1/2, where the effective diffusion coefficient of CO2 in the concrete of the existing reinforced concrete structure, which is determined by the condition D = (mo˖δ2) / (2C˖t ). The thickness of the neutralized layer δ is determined experimentally on an existing structure using a physicochemical method (phenolphthalein solution or using depth gauges. .Concentration of CO2 in air C should be determined by chemical analysis of air samples taken directly from the structure or take ≈ 0.03%. Re. the ability of concrete mo is determined by the formula mo = 0.4 (C˖p˖f), taking the amount of cement, kg per 1m3, respectively, the strength of concrete. neutralization of concrete is equal to f = 0.5.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130581949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"About one approach to the problems of impact of fine shells of the S.P. Timoshenko type","authors":"V. Bogdanov","doi":"10.32347/TIT2141.0301","DOIUrl":"https://doi.org/10.32347/TIT2141.0301","url":null,"abstract":"The method of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind and the convergence of this solution are well studied. Such approach has been successfully used for cases of the investigation of problems of the impact a hard bodies and an elastic fine shells of the Kirchhoff–Love type on elastic a half-space and a layer. In this paper an attempt is made to solve the plane and the axisymmetric problems of the impact of an elastic fine cylindric and spheric shells of the S.P. Timoshenko type on an elastic half-space using the method of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind. The discretization using the Gregory methods for numerical integration and Adams for solving the Cauchy problem of the reduced infinite system of Volterra equations of the second kind results in a poorly defined system of linear algebraic equations: as the size of reduction increases the determinant of such a system to aim at infinity. This technique does not allow to solve plane and axisymmetric problems of dynamics for fine shells of the S.P. Timoshenko type and elastic bodies. It is shown that this approach is not acceptable for investigated in this paper the plane and the axisymmetric problems. This shows the limitations of this approach and leads to the feasibility of developing other mathematical approaches and models. It should be noted that to calibrate the computational process of deformation in the elastoplastic formulation at the elastic stage, it is convenient and expedient to use the technique of the outcoming dynamics problems to solve an infinite system of integral equations Volterra of the second kind.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124517882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrosion resistance of welded joints made by underwater wet welding","authors":"Sergey Maksimov, A. Radzievskaya, L. Nyrkova, Switlana Osadchuk","doi":"10.32347/TIT2141.0201","DOIUrl":"https://doi.org/10.32347/TIT2141.0201","url":null,"abstract":"One of the reasons of coming out of order of metal structures, operating in water environment, including sea conditions, is the corrosion. Thus, for example, the corrosion wear of metal of the ship hull underwater part can reach from 0.3 up to 0.5 mm/year. The corrosion of welds is the ever more critical situation. The rate of their fracture exceeds the rate of the base metal corrosion and in some cases it may reach 1-3 mm/year [1, 2]. The great selective corrosion in the form of fissures along the welds (on both sides) was observed in heat-affected zone (HAZ) metal of slot, butt welds and welds for welding-on to the basic workpiece, i.e. up to 1 mm/year, in some cases a through corrosion fracture of the fusion line (formation of blowholes) was observed [1]. In the opinion of the work authors [2] the welds are subjected to fracture due to the occurrence of thermal electromotive force between the parts welded under conditions of high electric conductivity of the sea water (Seebeck effect). \u0000To repair the corroded welded joints of metal structures, operated under the water, a wet underwater welding is used. At the E.O.Paton Electric Welding Institute the specialized flux-cored wires have been developed, which are designed for welding low-carbon and low-alloyed steels, including those of a higher strength. In the latter case the electrode materials of an austenite type are used to provide resistance against cold crack formation in the HAZ [3]. The work was aimed at study of corrosion resistance of welded joints with ferrite and austenite deposited metal, made by the underwater wet welding, under the conditions, which simulate the service conditions in sea water.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125206702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improvement of crane-manipulator equipment for emergency rescue and restoration works","authors":"M. Sukach, Anatoliy Kravchuk","doi":"10.32347/tit2141.0202","DOIUrl":"https://doi.org/10.32347/tit2141.0202","url":null,"abstract":"To implement state policy in the fields of civil protection, protection of the population and territories from emergencies and their prevention, emergency response, rescue, fire fighting, fire and man-made safety, emergency services, as well as hydrometeorological activities There is the State Service of Ukraine for Emergencies (hereinafter SES of Ukraine) [1]. 7 emergency rescue formations (central subordination), including aviation, are subordinated to it; 25 emergency rescue teams of special purpose and 1182 district fire and rescue units (territorial subordination) [2]. \u0000According to the main capabilities of the units of the Rescue Service of Civil Defense are divided into: \u0000 1) units intended for extinguishing fires, rescuing people and property in case of fires, at facilities and territories, regardless of subordination and form of ownership, conducting emergency rescue operations, providing primary medical care to victims. \u00002) formation (detachments, centers) designed to eliminate accidents (catastrophes) of technogenic, natural and military nature, the consequences of natural disasters (earthquakes, storms, landslides, landslides, mudslides, floods, snow snowdrifts, icing, etc.), search and rescue, fire and rescue operations, international rescue operations, demining activities and civil and territorial defense measures, national and regional in nature. \u0000They include: \u0000- fire and rescue units - for firefighting, rescue of people and property at facilities and territories, regardless of subordination and form of ownership. - rescue units - designed to deploy and carry out rescue and other urgent work in the shortest possible time, to search (including the use of service dogs) and rescue people who are in destroyed, burning buildings, under the rubble, including excavation of victims from collapsed buildings, as well as to provide first aid to victims; \u0000- engineering - for conducting engineering reconnaissance of routes and centers of destruction, clearing of blockages, excavation of victims from under the damaged constructions, creation of special passages in blockages, collapse of designs, detection of damages in utility and energy and technological networks, preparation and maintenance of roads, formation of fencing anti-fire lanes; \u0000- radiation and chemical protection - conduct radiation and chemical reconnaissance, carry out dosimetric and chemical control of units, perform degassing, decontamination of uniforms and other material means, areas, roads and structures; \u0000- pyrotechnic - detect and destroy unused ammunition, including aircraft bombs and other explosive devices, neutralize the affected structural elements of buildings and houses, as well as pierce passages in the rubble by explosive methods; \u0000--water supply - designed for the development of water sources and equipment of water supply points; \u0000 - communication - to establish and maintain reliable communication, which provides communication between departments, governing bodie","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133709093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of cyber threats for the Internet of Things","authors":"A. Belov, Maxim Delembovsky, V. Shklyar","doi":"10.32347/tit2141.0303","DOIUrl":"https://doi.org/10.32347/tit2141.0303","url":null,"abstract":"The modern world is impossible to imagine without information technology. Such technologies are based on the use of computer equipment and means of communication. Both in the real world and in the virtual world, there are crimes called \"cybercrimes\". Thus, energy facilities, transport systems, financial and banking structures, military and law enforcement agencies, trade, medical and scientific institutions are potential victims of cybercrime, including cyberterrorism. Surveillance cameras, motion sensors, biochips, smart appliances - all these things simplify our daily lives and make our modern life more comfortable. As the number of devices connected to the network grows, so does the number of cyber threats. For example, the smart refrigerator became part of the botnet and began to spread spam, and the smart coffee machine was the cause of the attack on industrial networks with the subsequent infection of computers. The Internet of Things, which in turn is simple and difficult to implement, also has some problems with information security. Sometimes developers, intentionally or unintentionally, leave an undocumented channel, which not only collects information about the use of the device, but also allows you to penetrate into the personal space of the end user. In case of personal data leakage, the purpose of fraudsters is usually personal data: names, postal addresses, e-mail addresses, credit card details or account information. This allows you to order goods online under someone else's name and pay for them using someone else's debit card or debiting a certain account. For the same purpose, phishing can be used, which involves the use of fictitious websites, e-mails or text messages to access personal data.","PeriodicalId":434555,"journal":{"name":"Transfer of innovative technologies","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128322154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}