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Tallinn, Estonia

Estonian Academy of Security science is a public vocational university in Estonia, established on 15 April 1992. Wikipedia.

Kulu P.,Tallinn University of Technology | Kaerdi H.,Estonian Academy of Security Sciences | Surzenkov A.,Tallinn University of Technology | Tarbe R.,Tallinn University of Technology | And 3 more authors.
International Journal of Materials and Product Technology | Year: 2014

Hardfacing is among the most economical methods for surface treatment and service life and efficiency improvement of metal parts subjective to wear. At the same time use of low-cost recycling technologies in the production of powders is of current interest. Focus in this paper is on: a) the production of hardmetal/cermet powders as reinforcements for composite coatings; b) deposition technologies and optimisation of coating structure; c) the wear resistance of coatings at different abrasive wear conditions. The article describes the production and grindability of hardmetal (WC-Co) and cermet (Cr 3C2-Ni, TiC-NiMo) powders and their size and shape. Results address the optimisation of the composition and structure of HVOF-sprayed and PTA-welded composite powder coatings based on the commercial spray powders and produced hardmetal/cermet powders. The abrasive wear resistance of coatings at different wear conditions (rubber wheel, erosion and impact wear tests) is analysed. Copyright © 2014 Inderscience Enterprises Ltd. Source

Tammepuu A.,Estonian Academy of Security Sciences | Sepp K.,Estonian University of Life Sciences
Journal of Risk Research | Year: 2013

Although risk assessment in the field of civil protection is a vital element of emergency and disaster prevention, EU policy directives do not promote a common methodological approach for evaluating the performance of emergency risk assessments (EmRAs). Consequently, new member states have based the development of their national risk assessment systems on examples from the EU-15 member states and elsewhere. The latest important trend in the EU is the construction of unified guidelines on risk assessment and mapping for disaster management. This paper explores the developments in and problems of the risk assessment of emergency situations in post-Soviet Estonia. In the 1990s, the requirements for EmRA in Estonia were vague; only since 1998 has the Chemicals Act established more concrete requirements for hazardous industrial plants. Entry into the EU required Estonia to abide by and implement EU regulations. The primary aim of the current study was to conduct a survey on the development of Estonian EmRA since the restitution of Estonia as an independent state (1991). A secondary aim was to examine the impact of guidelines from other states and international institutions on the process of developing Estonias regulations. Although this study emphasises the success of the key stages in the developmental process of Estonias EmRA system, it also demonstrates the need for further improvement of the systems legal and methodological basis, as well as the practical arrangement of EmRA. The problems and solutions of EmRA in Estonia have common features with those in other EU member states, and therefore more cooperation inside the Union is recommended. © 2013 Copyright Taylor and Francis Group, LLC. Source

Goljandin D.,Tallinn University of Technology | Sarjas H.,Tallinn University of Technology | Kulu P.,Tallinn University of Technology | Kaerdi H.,Estonian Academy of Security Sciences | Mikli V.,Tallinn University of Technology
Medziagotyra | Year: 2012

Recycling of materials is becoming increasingly important as industry response to public demands, that resources must be preserved and environment protected. To produce materials competitive in cost with primary product, secondary producers have to pursue new technologies and other innovations. For these purposes different recycling technologies for composite materials (oxidation, milling, remelting etc) are widely used. The current paper studies hard metal/cermet powders produced by mechanical milling technology. The following composite materials were studied: Cr3C2-Ni cermets and WC-Co hardmetal. Different disintegrator milling systems for production of powders with determined size and shape were used. Chemical composition of produced powders was analysed. To estimate the properties of recycled hard metal/cermet powders, sieving analysis, laser granulo metry and angularity study were conducted. To describe the angularity of milled powders, spike parameter-quadric fit (SPQ) was used and experiments for determination of SPQ sensitivity and precision to characterize particles angularity were performed. Images used for calculating SPQ were taken by SEM processed with Omnimet Image Analyser 22. The graphs of grindability and angularity were composed. Composite powders based on Fe- and Ni-self-fluxing alloys for thermal spray (plasma and HVOF) were produced. Technological properties of powders and properties of thermal sprayed coatings from studied powders were investigated. The properties of spray powders reinforced with recycled hardmetal and cermet particles as alternatives for cost sensitive applications were demonstrated. Source

Saar I.,Estonian Academy of Security Sciences
Traffic Injury Prevention | Year: 2015

Objective: This article examines the association between alcohol excise tax rates and alcohol-related traffic accidents in Estonia.Methods: Monthly time series of traffic accidents involving drunken motor vehicle drivers from 1998 through 2013 were regressed on real average alcohol excise tax rates while controlling for changes in economic conditions and the traffic environment. Specifically, regression models with autoregressive integrated moving average (ARIMA) errors were estimated in order to deal with serial correlation in residuals. Counterfactual models were also estimated in order to check the robustness of the results, using the level of non-alcohol-related traffic accidents as a dependent variable.Results: A statistically significant (P <.01) strong negative relationship between the real average alcohol excise tax rate and alcohol-related traffic accidents was disclosed under alternative model specifications. For instance, the regression model with ARIMA (0, 1, 1)(0, 1, 1) errors revealed that a 1-unit increase in the tax rate is associated with a 1.6% decrease in the level of accidents per 100,000 population involving drunk motor vehicle drivers. No similar association was found in the cases of counterfactual models for non-alcohol-related traffic accidents.Conclusions: This article indicates that the level of alcohol-related traffic accidents in Estonia has been affected by changes in real average alcohol excise taxes during the period 1998–2013. Therefore, in addition to other measures, the use of alcohol taxation is warranted as a policy instrument in tackling alcohol-related traffic accidents. © 2015, Taylor & Francis Group, LLC. Source

Tammepuu A.,Estonian Academy of Security Sciences | Sepp K.,Estonian University of Life Sciences
WIT Transactions on Ecology and the Environment | Year: 2011

This paper presents a comparative study of the national risk assessment outcomes of two different countries of the European Union: Estonia, as a socalled 'new member' and the UK as an 'old member'. The comparative survey was carried out on the basis of the National Summary of Emergency Risk Assessments of Estonia and the National Risk Register of Civil Emergencies of the UK. The features compared were requirements, methodologies, risk assessment process and performers, risk types and categories together with risk assessment outcomes as well as output documents' composition. Simultaneously parallels were drawn with local level emergency risk assessments. Although the risk types were defined diversely in the two countries, an indirect comparison was still accomplishable. For instance, the risk of pandemic human disease was assessed as one of the highest in both countries. On the grounds of our observations, the National Risk Register of the UK was comparatively more, an advising, guiding and directing document while the Estonian emergency risk assessment summaries were in a greater part of a summarizing character. © 2011 WIT Press. Source

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