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Implementation of the Energy Efficiency Directive: Opportunities and Challenges

REFERENCES: 1. European Parliament and the Council Directive 2012/27/EU on energy efficiency, amending Directives 2009/125/EC and 2010/30/EU and repealing Directives 2004/8/EC and 2006/32/EC [2012] OJ L 315. 2. LR Ekonomikas ministrija. (2013). Koncepcija par Eiropas Parlamenta un Padomes 2012. gada 25.oktobra Direktīvas 2012/27/ES par energoefektivitāti, ar ko groza Direktīvas 2009/125/EK un 2010/30/ES un atceļ Direktīvas 2004/8/EK un 2006/32/EK, prasību pārņemšanu normatīvajos aktos 2013. 3. LR Ekonomikas ministrija. (2013). Ziņojums par

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Evaluation of Signal Regeneration Impact on the Power Efficiency of Long-Haul DWDM Systems

References 1. Iyer, S., & Singh, S.P. (2016). Spectral and power efficiency investigation in single- and multi-line-rate optical wavelength division multiplexed (WDM) networks. Photonics Network Communications. doi: 10.1007/s11107-016-0618-3 2. Keiser, G. E. (1998). A review of WDM technology and applications. GTE Systems & Technology, 21. 3. Pavlovs, D., Grinčišins, A., Bobrovs, V., Gavars, P., & Ivanovs, Ģ. (2016). Research of 10 Gbps NRZ-OOK signal spectral and energy efficiency. In Proc. ELECTRONICS 2016

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Efficiency estimation for permanent magnets of synchronous wind generators

). Direct-drive contactless wind generator with concentrated winding. Latv. J. Phys. Tech. Sci., 49 (4), 14-20. 10. Bronstein I., & Semendaev K. (1948). Handbook of mathematics for engineers and university students. M.-L.: OGIZ, p. 556 (in Russian). 11. Serebryakov, A., Levin, N., & Sokolov, A. (2012). Efficiency improvement of directdriven synchronous generators with excitation from strontium-ferrite permanent magnets. Latv. J. Phys. Tech. Sci., 49 (4), p. 3-13.

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Precise determination of HPGe detector efficiency for gamma spectrometry measurements of environmental samples with variable geometry and density

: Model of vertical migration of 137 Cs. J. Environ. Radioact ., 80 , 87–103. 7. International Organization for Standardization. (1995). Guide to the expression of uncertainty in measurement . Geneva, Switzerland: ISO. 8. Bolívar, J. P., García-Tenorio, R., & García-León, M. (1994). A generalized transmission method for gamma-efficiency determination in soil samples. Nucl. Geophys ., 8 (5), 485–492. 9. Zikovsky, L. (1997). Variation of the detection efficiency of a Ge detector with the height of the sample in Marinelli beaker. J. Radioanal. Nucl

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Gas Combustion Efficiency Enhancement: Application Study of Intense Elestrostatic Field

REFERENCES 1. Davis, A., Mikelsons, K., Puikevica-Puikevska, I., Silantjeva, I., Zebergs, V., & Zeltins, N. (2007). The methods of analysis for raising the energy efficiency and the reduction of greenhouse gases. In: 27th USAEE/IAEE North American Conference: Developing & Delivering Affordable Energy in the 21st Century (pp. 24–25), USA, Houston, Texas, Book of extended abstracts. 2. Zhang, Y., Wu, Y., Yang, H., Zhang, H., & Zhu, M. (2013). Effect of high-frequency alternating electric fields on the behaviour and nitric oxide emission of laminar non

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Development of Information Models for Increasing the Evaluation Efficiency of Wireless Channel Parameters of 802.11 Standard

Performance Assessment of IEEE 802.11-based Wireless Networks. Mathematical and Computer Modelling , 53 , 2173–2191. 7. Yarilovets, A.V., Nazaruk, V.D., & Zaitsev, S.V. (2014). An Evaluation of the Efficiency of Information Technology for Wireless Access Systems Built on the Basis of Optimal Orthogonal Multi-Frequency Signal Constructions. Mathematical Machines and Systems , 2 , 51–58. 8. Amirgaliyev, B.Y., Kenshimov, C.A., Baibatyr, Z.Y., Kuatov, K.K., Kairanbay, M.Z., & Jantassov, A.K. (2015). Statistical Inference in ALPR System. In 9th International

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Involvement of Individuals in the Development of Technical Solutions and Rules of Management for Building Renovation Projects: A Case Study of Latvia

, Vilnius. ISSN 2029-4441 print / ISSN 2029-929X online. DOI: 10.3846/bm.2012.082 3. Legislation of the Republic of Latvia. (2016). Darbības programmas “Izaugsme un nodarbinātība” 4.2.1. specifiskā atbalsta mērķa “Veicināt energoefektivitātes paaugstināšanu valsts un dzīvojamās ēkās” īstenošanas noteikumi [Implementing rule of the Operational Programme “Growth and Employment” 4.2.1. the specific objective of the support “Promote energy efficiency investments in the public and residential buildings”]. Retrieved 8 November 2016, from

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Justification of the Utility of Introducing Smart Meters in Latvia

Directive 2003/54/EC [2009] OJ L 211:55, art 2, annex 1. 4. Barkans J., and Zalostiba D. (2009). Protection against Blackouts and Self-Restoration of Power Systems. Riga: RTU Publishing House. 5. Energy Business Reports. (2011). Smart Grid Industry Market Guide . Available at 6. Bariss, U., Kuzņecova, T., Laicāne, I., and Blumberga, D. (2014). Analysis of factors influencing energy efficiency in a smart metering pilot. Energetika 60 (2), 125–135. ISSN 0235-7208. 7. KPFI. Project No. KPFI-14/28 Overview of

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Thermal Characteristics of New Building Materials and their Effect upon the Energy Efficiency

References Petrovs, B., Puikevica-Puikevska, I., Zeltins, N. (2003). Evaluation of potential possibility of energy efficiency in dwelling. Proceedings: Healthy Buildings (Singapore), pp. 675-680. Ekmanis, Yu., Michna, J., Stania, A. & Zeltins, N. (2004). Uncertainty in energy conservation policy. Foundation for Energy and Environmental Policy , 6 Wolności, 41-700 Ruda Sląska, Poland, ISSN 0867-2172, ZESZYT NR 4/2004:38 p. Melko, A., Zebergs, V. & Zeltins, N. (2004). Energy

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Particle Size Distribution of E-Cigarette Aerosols and the Relationship to Cambridge Filter Pad Collection Efficiency


The relatively volatile nature of the particulate matter fraction of e-cigarette aerosols presents an experimental challenge with regard to particle size distribution measure-ments. This is particularly true for instruments requiring a high degree of aerosol dilution. This was illustrated in a previous study, where average particle diameters in the 10-50 nm range were determined by a high-dilution, electrical mobility method. Total particulate matter (TPM) masses calculated based on those diameters were orders of magnitude smaller than gravimetrically determined TPM. This discrepancy was believed to result from almost complete particle evaporation at the dilution levels of the electrical mobility analysis. The same study described a spectral transmission measurement of e-cigarette particle size in an undiluted state, and reported particles from 210-380 nm count median diameter. Observed particle number concentrations were in the 109 particles/cm3 range. Additional particle size measurements described here also found e-cigarette particle size to be in the 260-320 nm count median diameter range. Cambridge filter pads have been used for decades to determine TPM yields of tobacco burning cigarettes, and collection of e-cigarette TPM by fibrous filters is predicted to be a highly efficient process over a wide range of filtration flow rates. The results presented in this work provide support for this hypothesis.

Described here is a study in which e-cigarette aerosols were collected on Cambridge filters with adsorbent traps placed downstream in an effort to capture any material passing through the filter. Amounts of glycerin, propylene glycol, nicotine, and water were quantified on the filter and downstream trap. Glycerin, propylene glycol, and nicotine were effciently captured (> 98%) by the upstream Cambridge filter, and a correlation was observed between filtration efficiency and the partial vapor pressure of each component. The present analysis was largely inconclusive with regard to filter efficiency and particle-vapor partitioning of water. [Beitr. Tabakforsch. Int. 26 (2014) 183-190]

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