April 24, 2023 - mdg-magazine

Еng. vladislav stoykov, vlado_Prof. DSc. Eng. mihail mihaylov

ABSTRACT

The present works is related to the idea of researching and modeling stationary low pressure water fixed firefighting systems (FFFS) for fire protection of road tunnels with water mist. The GW M5 is tested, which is a compact, low pressure water mist nozzle specifically designed for overall and local use for protective water mist fire extinguishing systems. The main purpose of water mist systems is to prevent the full development of a fire in a road tunnel to its maximum capacity and, if possible, to ensure that damaged cars in a tunnel pipe can be separated from the rest of the passenger traffic, to localize and limit the spread of a possible fire inside a broken car. The operation of these FFFS will ensure the problem-free movement of other road users in the tunnel and also prevent the fire from spreading to other vehicles. Water mist systems are inherently effective in the early stages of fire development.

KEYWORDS

fires in road tunnels; fixed firefighting systems (FFFS); water mist - classes and characteristics; low pressure water mist nozzle; stand for testing nozzles

FULL ARTICLE IN PDF FORMAT

MODELLING OF FIXED FIREFIGHTING SYSTEMS WITH LOW PRESSURE WATER MIST NOZZLES

REFERENCES

1. Fire Protection of high-rise Buildings with Water Mist. UC LGN 23, June 2018, www.LocalGov.co.uc
2. EN14972-1:2020 The European watermist standard. Implementation date 30-th June 2021.
3. BDS EN 14972-1:2021. Statsionarni pozharogasitelni instalatsii. Instalatsii s vodna magla. Chast 1: Proektirane, montirane, kontrolirane i poddrazhka, publ.19.05.2021 g.
4. BDS EN 14972-3:2022. Statsionarni pozharogasitelni instalatsii. Instalatsii s vodna magla. Chast 3: Protokol ot izpitvane na sistemi s avtomatichni dyuzi za ofisi, uchilishtni klasni stai i hoteli, 20.01.2022 g.
5. DIRECTIVE 2004/54/EC on minimum safety requirements for tunnels in the trans-European road network, 18.7.2004.
6. GW Sprinkler A/S Kastanievej 15 DK-5620 Glamsbjerg Denmark CVR/VAT No: 31 79 65 12.
7. NFPA 750 Standard on Water Mist Fire Protection Systems, 2019.
8. NFPA 25 Standard on sprinkler inspection forms.
9. GW Sprinkler A/S SN010 1001D GW M5.
10. Antonov, I.S. Prilozhna mehanika na fluidite. S., 2009, 2016.
11. FFFS-EVS for Highway Tunnels – Literature Survey and Synthesis, January 2020. Доклад № FHWA-HIF-20-016.
12. PIARC, Fixed Fire Fighting Systems in Road Tunnels: Current Practices and Recommendations. Permanent International Association of Road Congresses, Technical Committee on Road Tunnel Operation, 3.3, 2016.
13. Mihaylov, M., D. Makedonska. Izsledavne na dyuzi za pozharogasene s fino razprasnata voda v patni tuneli, toplotehnika, Godina H, Kniga 1, 2019, ISSN 1314-2550.

SCIENTIFIC PUBLICATIONS by mdgmagazine April 24, 2023

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RISK ASSESSMENTIN THE MANAGEMENT OF MINING INVESTMENT PROJECTS USING THE RISK DISCOUNT FACTOR METHOD

Eng. Dimitar Shaykov

ABSTRACT

This article aims to clarify the process of risk management in mining investment projects, which is current due to its importance for the future profitability and efficiency of the investment activity. The future results of the investment activity in the mining industry are significantly influenced both by the shocks in the economic policy of the countries and by the numerous factors of the external and internal investment environment. A large part of them do not directly depend on economic subjects, and economic phenomena and processes are also under the influence of a large number of external factors to the investor. Economic evaluation and risk analysis are basic elements in the analysis of investment projects in the mining industry. In them, the importance of risk is determined by the need to carry out the most accurate risk assessment and incorporate the individual types of risk when determining the risk discount rate with which the expected net annual cash flows of the investment projects are discounted (updated). This leads to the determination of a risk discount rate that reflects the expected future profitability of the projects implemented by the investor. The determination of the risk discount rate is based on the risk discount factor method, also known as the risk accumulation method. On this basis, the investor can really assess the attractiveness of the investment projects

KEYWORDS

risk assessment, economic assessment, mining investment projects, risk discount factor

FULL ARTICLE IN PDF FORMAT

RISK ASSESSMENTIN THE MANAGEMENT OF MINING INVESTMENT PROJECTS USING THE RISK DISCOUNT FACTOR METHOD

REFERENCES

1. Mitev, V. Metodika za ikonomicheska otsenka na vazmozhnostite za efektivno razrabotvane na novi nahodishta. І. Sashtnost na razrabotenata metodika. Sp. „Minno delo i geologia”, br. 1, 2005, s. 19-22.
2. Mitev, V. Metodika za ikonomicheska otsenka na vazmozhnostite za efektivno razrabotvane na novi nahodishta. ІІ. Rezultati ot prilozhenieto na metodikata v realni uslovia. Sp. „Minno delo i geologia”, br. 2/2005, s. 13-18.
3. Brankova, B., P. Zlatanov. Analiz na riska pri ikonomicheskata otsenka na minnite investitsii. Godishnik na Minno-geolozhkia universitet „Sv. Ivan Rilski“, tom 44, svitak IV, „Humanitarni i stopanski nauki“, 2003, s. 35-39.
4. Mitev, V. Otsenka na zapasite i resursite na nahodishtata na polimetalni rudi. Godishnik na MGU „Sv. Iv. Rilski”, t. 50, sv. ІV, „Humanitarni i stopanski nauki“, 2007, s. 53-58.
5. Radev, J. Economic analysis of investment projects in mining industry. Annual of University of Mining and geology “St. Ivan Rilski”, vol. 46, part ІV, “Humanitarian and Economic Sciences”, 2003, рр.49-54.
6. Mitev, V. Vidove risk i metodi za otsenka na riska pri investitsionnite proekti v minnia otrasal. Godishnik na MGU „Sv. Iv. Rilski”, t. 47, sv. ІV „Humanitarni i stopanski nauki“, 2004, s. 49-53.
7. Mitev, V. Klasifikatsia na metodite za otsenka na investitsionni proekti v minnia otrasal. Godishnik na MGU „Sv. Iv. Rilski”, t. 46, sv. ІV, „Humanitarni i stopanski nauki“, 2003, s. 55-60.
8. Mitev, V. Management of the quantity and quality of the reserves and resources of ore deposits. Journal of Mining and Geological Sciences, Vol. 62, Number 4, 2019, p. 09-14.
9. Yordanov, M. Otsenka na nahodishtata na etap Pre-feasiility study i Feasibility study s analiz na parichnite pototsi, I chast – Osnovni termini i ponyatia. Sp. „Minno delo i geologia“, br. 1/1998.
9. Yordanov, M. Otsenka na nahodishtata na etap Pre-feasiility study i Feasibility study s analiz na parichnite pototsi, I chast – Osnovni termini i ponyatia. Sp. „Minno delo i geologia“, br. 1/1998.

SCIENTIFIC PUBLICATIONS by mdgmagazine April 24, 2023

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ЕКСПРЕСЕН АНАЛИЗАТОР ЗА УСТАНОВЯВАНЕ НА ЪГЛИТЕ НА ОТКОСИТЕ ЗА ЛИТОЛОЖКА РАЗНОВИДНОСТ, ИЗПОЛЗВАНИ ПРИ ПРОЦЕСА НА ОПТИМИЗАЦИЯ НА РУДНИК „ЕЛАЦИТЕ”

Инж. Ивайло Николов, Инж. Никола Тошков, Геол. Желязко Ялъмов, Инж. Любомир Свиленов

ABSTRACT

Ъгълът на откоса за отделна литоложка разновидност е важен входен параметър при проектирането на открити рудници. Той трябва да е оптимален и съобразен с приетия праг на сигурност. Настоящият доклад представя разработената методика за намиране на оптималния ъгъл на откоса за литоложка разновидност в софтуера UDEC, чрез програмния език FISH, приложен в условията на рудник „Елаците“. Разработеният програмен код извършва множество стабилитетни изчисления на автоматично генерирани геометрични конфигурации, зависещи от броя и височината на рампите, широчината на геотехническите площадки и междурамповия ъгъл. Оценява влиянието на подземните води в зависимост от дълбочината на водното ниво и вероятността за загуба на устойчивост, според вариацията на якостните параметри.

KEYWORDS

устойчивост на откоси, оптимален ъгъл на откоса по литологии

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ЕКСПРЕСЕН АНАЛИЗАТОР ЗА УСТАНОВЯВАНЕ НА ЪГЛИТЕ НА ОТКОСИТЕ ЗА ЛИТОЛОЖКА РАЗНОВИДНОСТ, ИЗПОЛЗВАНИ ПРИ ПРОЦЕСА НА ОПТИМИЗАЦИЯ НА РУДНИК „ЕЛАЦИТЕ”

REFERENCES

1. Hoek, Evert. 2007. Practical Rock Engineering.
2. Itasca Inc. 2018. Fish in UDEC 7.0.
3. Itasca Inc. 2018. UDEC 7.0 User’s Guide.
4. Read, John, and Peter Stacey, eds. 2010. Guidelines for Open Pit Slope Design. Collingwood, Vic: CSIRO Publ.
5. Rosenbleuth, E. 1981. Two-point estimates in probabilities. J. Appl. Math. Modelling 5, October, 329-335.

NEWS by mdgmagazine April 24, 2023

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ISSUE 3-4/2023 OF THE MAGAZINE "MINING AND GEOLOGY" E ON THE SITE

НАКРАТКО

Може да намерите брой 3-4/2023 г. на списание “Минно дело и геология” в раздел АРХИВ.