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Reduction of heat and mechanical losses is a critical factor in reducing CO2 emissions and fuel consumption of automotive engines. Toward that end, it is necessary to investigate the lubrication conditions of engine sliding surfaces and instantaneous heat flux in the combustion chamber in order to obtain experimental data for validating computer-aided engineering (CAE) calculations. The authors used thin-film sensors to measure the distribution of the oil film pressure on the sliding surfaces of engine parts including pistons, bearings and gear tooth surfaces. This paper describes the structure and configuration of the thin-film sensors and the measurement system used for direct observation, especially of piston pins, and presents the measured results.

The importance of reliable information is substantiated in terms of aerodynamic angles and air speed for piloting, control, and ensuring the flight safety of airplanes and other types of aerial vehicles in the surface layer of the atmosphere. Analytical models are developed and results of calculating the methodological aerodynamic errors of measuring the true air speed, indicated speed, Mach number, and aerodynamic angles of attack and slip for the panoramic sensor of the air speed vector parameters, are presented. The ways are considered of reducing the systematic and random components of aerodynamic methodological errors by introducing the corrections to calculation algorithms, implementing the principles of interconnecting and optimal filtration. [ABSTRACT FROM AUTHOR]

Several digital image analysis systems have been developed for surface calculation of vitiligo lesions. Critical assessment of their measurement properties is crucial to support evidence‐based recommendations on the most suitable instruments and will reveal the need for future research. A systematic review was performed to systematically summarize, compare, and critically assess the measurement properties of digital and analogue analysis systems for surface calculation of vitiligo lesions following the Consensus‐Based Standards for the Selection of Health Measurement Instruments (COSMIN) recommendations. Nineteen clinical trials were selected including 25 different instruments. Manual tracing on transparent sheets (contact planimetry) combined with digital measurement or point counting can be considered as the best validated method for the evaluation of target lesions taking into account the skin curvatures. Two‐dimensional digital imaging analysis on photographs seems also robust although confirmatory data of different research groups using the same digital instrument in a wide range of skin types are missing. Analysis based on 3D photography is still in its early stage but is promising for whole‐body analysis. However, the reported data on the quality of the instruments for surface area calculation of vitiligo lesions were in general rather limited. Therefore, future high‐quality validation studies are required also including full body evaluations. [ABSTRACT FROM AUTHOR]

Penelitian ini bertujuan untuk menganalisis pengaruh adanya tower seluler terhadap kualitas penerimaan siaran TV di daerah padat penduduk yang berada di Jalan Buring Dalam Kecamatan Klojen, Kota Malang. Dari hasil pengukuran nilai kuat medan secara Line of Sight dan With Obstacle akan diketahui nilai redaman yang terjadi akibat adanya obstacle dengan jenis seluler. Setelah dilakukan pengukuran, akan dibandingkan dengan hasil perhitungan. Hasil penelitian ini adalah analisa pengaruh dari obstacle dengan jenis tower seluler terhadap pensinyalan tv analog, dengan membandingkan hasil pengukuran dan perhitungan yang didapat dari perhitungan kuat medan yang diterima menggunakan perhitungan redaman berdasarkan Rekomendasi ITU-R P.1546-1 dengan metode Okumura Hata, dan teori difraksi knife edge. Kesimpulan, hasil pengukuran dengan adanya obstacle tower seluler diperoleh rata – rata selisih antara Line of Sight dan With Obstacle sebesar 2.6525 dB dengan jarak obstacle 15 m dari titik pengukuran, dan 4.548571 dB dengan jarak 40 m . Nilai estimasi redaman rata – rata yang dipengaruhi difraksi tower seluler dengan jarak obstacle 15 m dari titik pengukuran sebesar 41.1088 dB, dan dengan jarak 40 m sebesar 36.67143 dB.Nilai redaman tower seluler berdasarkan pengukuran untuk jarak 15 m dari obstacle didapatkan nilai sebesar 2.6525 dB dan untuk perhitungan sebesar 41.1088 dB Sedangkan nilai redaman tower seluler berdasarkan hasil pengukuran untuk jarak 40 m memiliki rata – rata sebesar 4.548571 dB dan untuk perhitungan sebesar 36.67143 dB.

The presented paper provides the alternative options for determining the condition of belt gear based on the testing and monitoring. In order to carry out experimental measurements, a newly developed device for testing, monitoring and diagnostics of belt drives was designed, as well as the possibility of determination of limit states by extreme loads. The designed measuring stand allows to determine the point of destruction of the belt for an extreme load. The main objective of the experimental measurement was to determine the slip of the wedge-shaped belt. The slip was evaluated by the coefficient of belt creeping and the specific belt slip by means of the measuring stand. The measurements on the proposed device can be made when the input speed from the electric motor and the transmitted torque of the belt gear are constant while the tensioning force of the belt drive is changing or the measurements can be made when the tensioning force and input speed of the belt drive are constant and the torsional moment changes. The monitoring of specified parameters for determining the belt gear slip is made by means of sensors located at predetermined locations from which data is processed by a PC. In the paper, the analytical calculation is processed, from which the values are compared with the values measured on the proposed device.

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Highlights • Comparison of measurement and calculation results regarding floor vibration properties. • Evaluation of the serviceability of wooden joist floors. • Results indicate that it not is possible to verify the Eurocode method with respect to accuracy. • Results presented in the paper show that sufficient accuracy may be achieved using parameters from the Hu and Chui method. Abstract Timber floor constructions are very common in the Nordic countries, for instance in single- and multifamily buildings. But building with wood is increasing in popularity for other building categories and there is wider interest in increasing the span width of wooden joist floors. Static and vibrational performance become crucial for serviceability of timber floors and often limit the design; however, constructors and designers want to increase the floor span width. To meet these challenges, reliable design methods are required and have therefore become a focus in many countries. This paper presents results from a number of measurements of different joist floor constructions. Parameters measured have also been calculated according to given equations and relevant methods. Both calculations and measurements include 17 laboratory objects and four field objects. The objects represent a huge variety of solutions and therefore a large spread of results. The main reason for the selection of floor solutions was to expand the possibilities and test the methods more than tuning current solutions into satisfactory floor vibration perception. The data and resulting analysis in this paper highlight benefits and limitations concerning relevant parameters for evaluation of floor vibration perception. According to this work, it is not possible to verify the Eurocode method with respect to accuracy, and the link to perception of floor vibrations is rather low. Another method should be used or developed for the future. Results presented in this paper show that sufficient accuracy may be achieved using parameters from the Hu and Chui (2004) method. Experiences from Norway over the last five years are also promising regarding evaluation of floor vibration perception using this method. However, attention should be given to floors with significantly lower damping properties and/or significantly higher (modal) masses. Damping properties or an alternative parameter taking a longer time interval of the vibrations into account should be considered. [ABSTRACT FROM AUTHOR]

This paper presents information about a new device for measuring the synchronous machine load angle in laboratory conditions using the optical encoder. The prototype device is used in education for practical measuring exercises in the study course of electrical machines. Described in the article is block diagram of the measuring device. The operation principle of the device and the measurement principle of load angle of the synchronous machine presents a subject of the article, too. Moreover, the device evaluates operating mode (motor or generator) of the synchronous machine. [ABSTRACT FROM AUTHOR]

Background: No gold standard exists for renal volumetry in vivo. Purpose: To devise and evaluate segmentation methods on magnetic resonance imaging (MRI) datasets. Material and Methods: Five combinations of MRI pulse sequences and measuring methods were used to measure the renal volumes of five men aged 54-72 years scanned before autologous renal stem cell transplantation and three, six, and 12 months post transplantation. Results: Renal volume did not change after stem cell transplantation. The results varied considerably: the reproducibility (coefficient of variation) was 4.0-6.0% and measurements took 1-13 min per kidney. Manual segmentation of images from the volumetric interpolated breath-hold examination (VIBE) without fat saturation sequence provided best reproducibility but was time-consuming. Use of the ellipsoid formula from half Fourier acquisition single shot turbo spin echo (HASTE) provided the fastest measurement, but resulted in lower reproducibility. Conclusion: Renal volumetry based on images from the pulse sequence VIBE without fat saturation acquired using an out-of-phase TE may be investigated further, possibly in combination with the quick ellipsoid formula. [ABSTRACT FROM AUTHOR]

This paper focuses on the topics U-values and indoor air temperatures of unheated basements with uninsulated cellar ceilings. Measurement values are compared with calculation procedures suggested by building regulations. Concerning the U-values it is shown that they are typically considered to be higher (i.e. worse) in uninsulated existing constructions than they effectively are. Measured temperatures in seven basements are higher (around 8 K) than a calculation according to regulations would yield. The paper derives suggestions for the adjustment of calculations focused on existing residential buildings. [ABSTRACT FROM AUTHOR]

Ecosystem services (ES) are increasingly used as the conceptual driver for conservation and development actions, largely following from the infl uential Millennium Ecosystem Assessment. Scholars skeptical of the neoliberal turn in conservation have critiqued the use of economic values for nature's services. What has been less well understood and reviewed, however, is how concepts of ES are enacted by technologies of calculation, as well as how calculative practices move through networks and among stakeholders. This review traces how defi nitions and metrics of ES have evolved and how they are used, such as in biodiversity off setting and wetland mitigation programs. Using the idea of the creation and deployment of calculative mechanisms, this article discusses how these processes proceed in diff erent ES contexts, assesses what work has to happen ontologically to make ES commensurable and circulatable, and speculates on what the opportunities for future pathways other than commodification are. [ABSTRACT FROM AUTHOR]

Measuring and being measured are some of the fundamental aspects of our worlds. Without them, we cannot live in our environments or function as social beings. But how we measure, and are measured, and to what ends and purposes, matters a great deal. Measurement does not just record; it shapes, changes, and constitutes things. It is not merely descriptive. It is creative. This introduction to the special issue explores how these themes of measurement are played out in diverse settings, including counting fi sh stocks, migration, social resilience, local measures of sustainability, oil exploitation, forest conservation, calculating ecosystem services, and measuring heat. Collectively, they provide a better understanding of how crucial measurements are formulated, and how they are and can be contested. [ABSTRACT FROM AUTHOR]

Absorption characteristics of a Helmholtz resonator positioned at the end wall of a circular duct are considered. The absorption coefficient of the resonator is experimentally investigated as a function of the diameter and length of the resonator neck and the depth of the resonator cavity. Based on experimental data, the linear analytic model of a Helmholtz resonator is verified, and the results of verification are used to determine the dissipative attached length of the resonator neck so as to provide the agreement between experimental and calculated data. Dependences of sound absorption by a Helmholtz resonator on its geometric parameters are obtained. [ABSTRACT FROM AUTHOR]

In this investigation, a numerical model expressing advection and diffusion effects is used to examine air temperature rise in urban areas that are on the leeward side of green areas. The model results are then verified by comparison with measurement results. When the measurement point is at a distance of 30 m or more from a green area, the air temperature of the urban area is not affected by the green area. An isotropic diffusion model and a model incorporating buoyancy were applied for the vertical diffusion term. Results of air temperature rise with distance from the green area were compared for both calculated and measured values. The rise in air temperature due to the development of the urban boundary layer in the area near a green space is expressed using the sensible heat flux from the ground surface, the distance from the green area and the wind velocity. We considered an approximation of air temperature rise in order to express the following situation: when entering the urban area, air temperature rises sharply, and when reaching a certain distance from a green area, it becomes almost constant. [ABSTRACT FROM AUTHOR]

This paper investigates mathematical ideas found in a Jaina non-mathematical text, by which I mean a work not dedicated to mathematics as a separate scholarly discipline. The Aṇuogaddārāiṃ (approximately 4 century CE), a Prakrit text from the Śvetāmbara Āgamas, explains the methods a Jaina monk should use in investigating a scriptural text. This work shows a remarkable ability to deal with numerical concepts and quantitative descriptions of all kinds. I shall often compare its mathematical content with texts from different Sanskrit bodies of knowledge. This paper demonstrates that the Aṇuogaddārāiṃ, as well as presenting a wealth of mathematical information, expounds a Jaina theory of numbers that has been so far disregarded by historiography. In order to understand this formulation, I shall propose an analytical-interpretative model to then improve the English translation by Hanaki 1970. In Jainism, the knowledge of the true nature of the universe was a requisite to progressing towards a full awareness of the human condition and hence towards the path of liberation. Numerical data and detailed calculations provide minute descriptions of the universe and matters related to karma and liberation. I shall argue that the Aṇuogaddārāiṃ testifies that mathematics was a perfect, functional instrument for representing Jaina cosmological and soteriological models. [ABSTRACT FROM AUTHOR]

The number of incident cancers and long-term cancer survivors is expected to increase substantially for at least a decade. Advanced-technology radiotherapies, e.g., using beams of protons and photons, offer dosimetric advantages that theoretically yield better outcomes. In general evidence from controlled clinical trials epidemiology studies are lacking. To conduct these studies, new research methods and infrastructure will be needed. In the paper, we review several key research methods of relevance to late effects after advanced-technology proton-beam and photon-beam radiotherapies. In particular, we focus on the determination of exposures to therapeutic and stray radiation and related uncertainties, with discussion of recent advances in exposure calculation methods, uncertainties, in-silico studies, computing infrastructure, electronic medical records, and risk visualization. We identify six key areas of methodology and infrastructure that will be needed to conduct future outcome studies of radiation late effects.

Proper determination of the effective electrode spacing (d eff ) of an ion chamber ensures proper determination of its collection efficiency either in continuous or in pulsed radiation in addition to the proper evaluation of the transit time. Boag's method for the determination of d eff assumes the spherical shape of the internal electrode of the spherical ion chambers which is not always true, except for some cases, its common shape is cylindrical. Current work provides a new approach for the evaluation of the effective electrode spacing in spherical ion chambers considering the cylindrical shape of the internal electrode. Results indicated that d eff values obtained through current work are less than those obtained using Boag's method by factors ranging from 12.1% to 26.9%. Current method also impacts the numerically evaluated collection efficiency ( f ) where values obtained differ by factors up to 3% at low potential ( V ) values while at high V values minor differences were noticed. Additionally, impacts on the evaluation of the transit time ( τ i ) were obtained. It is concluded that approximating the internal electrode as a sphere may result in false values of d eff , f , and τ i . [ABSTRACT FROM AUTHOR]

The number of incident cancers and long-term cancer survivors is expected to increase substantially for at least a decade. Advanced technology radiotherapies, e.g., using beams of protons and photons, offer dosimetric advantages that theoretically yield better outcomes. In general, evidence from controlled clinical trials and epidemiology studies are lacking. To conduct these studies, new research methods and infrastructure will be needed. In the paper, we review several key research methods of relevance to late effects after advanced technology proton-beam and photon-beam radiotherapies. In particular, we focus on the determination of exposures to therapeutic and stray radiation and related uncertainties, with discussion of recent advances in exposure calculation methods, uncertainties, in silico studies, computing infrastructure, electronic medical records, and risk visualization. We identify six key areas of methodology and infrastructure that will be needed to conduct future outcome studies of radiation late effects. [ABSTRACT FROM AUTHOR]

We improved a calculation procedure of neutron-flux distribution in the Primary Containment Vessel (PCV) to get reliable estimation of radioactivity inventory, which is crucial for specification of a decommissioning plan of nuclear power plants. We calculated two-dimensional (2D) distribution of neutron-flux in cylindrical coordinate (r–z) with a 2D discrete ordinate (Sn) code DORT by utilizing knowledge of the characteristics of neutron-flux distribution in the PCV of Tsuruga Nuclear Power Plant unit 1 (TS-1). The knowledge was obtained from measurements and three-dimensional (3D) calculation of neutron-flux distribution in cylindrical coordinate (r– θ –z) with a 3D Sn code TORT. The measurements were performed by using activation foils at 30 locations where the distribution characteristics could be observed in the PCV. The 3D calculation provided us better qualitative understandings about the characteristics of neutron-flux distribution in the PCV. An improved model of 2D calculation of neutron-flux distribution was generated by utilizing the knowledge from the measurements and the 3D calculation in the PCV. The reliability of 2D calculation was confirmed by comparing calculated fluxes with measured ones at locations where measurements were performed. The comparison between them showed that neutron-flux distribution calculated by the improved 2D model has met our criteria of the reliability. Therefore, the improved procedure provided a reliable 2D distribution of neutron-flux. [ABSTRACT FROM AUTHOR]

This paper presents comparisons between the effectiveness of the emergency protection under both stationary and nonstationary formulations calculated with the use of the RADUGA-7.5 package [1] and experimental data obtained in measuring the 'weight' of the emergency protection in the process of physical start-up of the VVER-1000 reactor of unit no. 3 of the Kalinin NPP. On the basis of the results obtained, recommendations are given on comparing the measured and calculated reactivity and parameters determined by using its value. [ABSTRACT FROM AUTHOR]

The article presents a computational method of assessing low-frequency electric and magnetic fields of AC 25 kV/50 Hz power supply systems. Different measurements of magnetic flux density and electric field strength on different contact line design were conducted. The fact that the traction current varies trough time presents difficulty in measuring the magnetic flux density. The comparison of measurements with calculations' results shows good agreement. Analysis of the results shows that the amounts of magnetic flux density and electric field of the contact network in areas where people reside are below the limit prescribed by national legislation. [ABSTRACT FROM AUTHOR]

Abstract: Effects of solute included in a sample on the specific enthalpy of ice are investigated experimentally. In the experiments, ice including the solute was made from an aqueous solution, and the specific enthalpy was measured by melting the ice in the aqueous solution. Moreover, a physical model of the ice including the solute is proposed. As a result, when the concentration of the aqueous solution is set at a value equivalent to the concentration of the sample, the specific enthalpy of the sample increases with the concentration of the sample. The measurement results and the calculated values agree well, and it was found that the method for calculating the specific enthalpy of the sample is valid. Moreover, when the concentration of the aqueous solution is higher than that of the ice including the solute, it was found the calculation method for the specific enthalpy of the sample is appropriate. [Copyright &y& Elsevier]

Abstract: This article presents the general procedure for uncertainty calculation of net total cooling effect estimation for rating room air conditioners and packaged terminal air conditioners, by means of measurements carried out in a test bench specially designed for this purpose. The uncertainty analysis presented in this work looks for establishing a confidence degree or certainty of experimental results. It is particularly important considering that international standards related to this type of analysis are too ambiguous when treating this subject. The uncertainty analysis is on the other hand an indispensable requirement to international standard ISO 17025 [ISO, 2005. International Standard. 17025. General Requirement to Test and Calibration Laboratories Competences. International Organization for Standardization, Geneva.], which must be applied to obtain the required quality levels according to the Word Trade Organization WTO. [Copyright &y& Elsevier]

A calculation method for the electric field over the ground surface under double-circuit HVDC transmission lines is proposed to satisfy the engineering design requirement. A comparison of the calculation results with the experimental measurement results finds that the maximal values and lateral distributions of the electric field over the ground surface under this type of line are obviously affected by different pole arrangement schemes and unequal corona onset electric fields of the positive and negative poles, and the maximal values and lateral distributions of the electric field over the ground surface under this type of line with diversified pole arrangement schemes can be predicted by using this method. [ABSTRACT FROM AUTHOR]

Economic science generally takes as its model system the results of uncoerced market transactions, and the application of economic rationality to the state is often understood as an effort to make public institutions behave more like private firms. This requires the explicit formulation of calculations that entrepreneurs are presumed to make implicitly. Yet a formal system of calculation can never be the same as a set of unarticulated practices, and economic projects such as cost-benefit analysis led quickly to the measurement of objects undreamed of by the private economy. Also, the relentless advance of economic quantification has created systems of oversight and regulation that tend to centralize rather than diffuse power. Historically, the methods of economic calculation did not follow from a quantified theory of individual market behavior, but, quite the contrary, were articulated as instruments of economic management and then applied back to individuals. As economics worked out a theory of market behavior, it simultaneously gave new meaning to the very idea of economic rationality. [ABSTRACT FROM AUTHOR]

Abstract: In this study, latent heat of fusion of ice in aqueous solutions was measured to understand latent heat of fusion of ice slurries. Propylene glycol, ethylene glycol, ethanol, NaCl and NaNO3 solutions were used as aqueous solutions. For measurements, pure ice was placed into solution, and temperature variations of the solution due to melting of ice were measured. Effective latent heat of fusion was calculated using an energy balance equation. Concentration of the solution varied due to ice melting, and dilution heat was considered. Therefore, latent heat of fusion of ice in aqueous solutions was predicted by considering the effects of dilution and freezing-point depression. We found that effective latent heat of fusion of ice decreased with increasing concentration of the solution, and effective latent heat of fusion was derived from latent heat of fusion of pure ice, effects of freezing-point depression, and dilution heat. [Copyright &y& Elsevier]

Better quantification of isotope ratios of atmosphere-ecosystem exchange of CO 2 could substantially improve our ability to probe underlying physiological and ecological mechanisms controlling ecosystem carbon exchange, but the ability to make long-term continuous measurements of isotope ratios of exchange fluxes has been limited by measurement difficulties. In particular, direct eddy covariance methods have not yet been used for measuring the isotopic composition of ecosystem fluxes. In this article, we explore the feasibility of such measurements by (a) proposing a general criterion for judging whether a sensor’s performance is sufficient for making such measurements (the criterion is met when the contribution of sensor error to the flux measurement error is comparable to or less than the contribution of meteorological noise inherently associated with turbulence flux measurements); (b) using data-based numerical simulations to quantify the level of sensor precision and stability required to meet this criterion for making direct eddy covariance measurements of the 13 C/ 12 C ratio of CO 2 fluxes above a specific ecosystem (a mid-latitude temperate forest in central Massachusetts, USA); (c) testing whether the performance of a new sensor—a prototype pulsed quantum cascade laser (QCL) based isotope-ratio absorption spectrometer (and plausible improvements thereon)—is sufficient for meeting the criterion in this ecosystem. We found that the error contribution from a prototype sensor (∼⃒0.2 ‰, 1 SD of 10 s integrations) to total isoflux measurement error was comparable to (1.5 to 2×) the irreducible ‘meteorological’ noise inherently associated with turbulent flux measurements above this ecosystem (daytime measurement error SD of ∼⃒60 % of flux versus meteorological noise of 30–40 % for instantaneous half-hour fluxes). Our analysis also shows that plausible instrument improvements (increase of sensor precision to ∼⃒0.1 ‰, 1 SD of 10 s integrations, and increased sensor stability during the half-hour needed to integrate eddy covariance measurements) should decrease the contribution of sensor error to the point where it is less than the contribution from meteorological noise. This suggests that new sensors using QCL-based isotope ratio absorption spectroscopy should make continuous long-term observations of the isotopic composition of CO 2 fluxes via eddy covariance methods feasible. [ABSTRACT FROM AUTHOR]

This paper presents first results of a comparison of dose rates calculated by SCALE 4.4a with measured dose rates at a CASTOR HAW 20/28 CG cask. This type of CASTOR cask is used for the transport and interim storage of vitrified high active waste (HAW) from reprocessing. The calculations were done using the SCALE code system which was developed by Oak Ridge National Laboratory (ORNL). The measurements were carried out in January 2003. The results show that the SCALE code system is a suitable tool for shielding assessment tasks to verify compliance with dose rate limits. However, this comparison shows that additional work is necessary to obtain a better correlation between calculation and measurement. [ABSTRACT FROM AUTHOR]

Soil erodibility is an important index to evaluate the soil sensitivity to erosion. The research on soil erodibility is a crucial tache in understanding the mechanism of soil erosion. Soil erodibility can be evaluated by measuring soil physiochemical properties, scouring experiment, simulated rainfall experiment, plot experiment and wind tunnel experiment. We can use soil erosion model and nomogram to calculate soil erodibility. Many soil erodibility indices and formulae have been put forward. Soil erodibility is a complex concept, it is influenced by many factors, such as soil properties and human activities. Several obstacles restrict the research of soil erodibility. Firstly, the research on soil erodibility is mainly focused on farmland; Secondly, soil erodibility in different areas cannot be compared sufficiently; and thirdly, the research on soil erodibility in water-wind erosion is very scarce. In the prospective research, we should improve method to measure and calculate soil erodibility, strengthen the research on the mechanism of soil erodibility, and conduct research on soil erodibility by both water and wind agents. [ABSTRACT FROM AUTHOR]

Abstract: A detailed dosimetry study was carried out in 12 regions of Ramsar having some elevated-level natural radiation areas (ELNRA) for the determination of effective doses of public from internal and external exposures indoors and outdoors. The 222Rn levels were measured by using the AEOI passive radon diffusion chambers indoors of about 500 houses in two separate studies in autumn and in winter, and also in some locations outdoors. The 222Rn and its progeny and equilibrium factors were also determined indoors and outdoors of some buildings by the active Pylon AB-5 system based on which the effective equivalent dose (E) of the public was determined. The annual mean effective equivalent dose (Ē) in different regions due to 222Rn ranges from 2.48 to 71.74 mSv with maximum levels up to 640 mSv determined in one house in Talesh Mahalleh. The annual Ē value from external exposures, as determined in 1000 locations outdoors and in 800 locations indoors, were reported in another paper before which range from 0.6 (in normal background areas) to 6 mSv (in the ELNRA) with maximum values up to 135 mSv in the above-stated house with a high radon level. This paper mainly reports the 222Rn levels indoors and outdoors and the effective equivalent doses due to 222Rn and its progeny and concludes some results of total annual effective equivalent doses of public due to external and internal exposures. [Copyright &y& Elsevier]

In a fin-tube heat exchanger the contact between fin collar and tube surface is obtained through mechanical expansion of tubes. Since the interfaces between the tubes and fins consist partially of metal-to-metal contact and partially of air, the features of heat transfer through the contact interfaces have not been fully investigated. The present study aims at the development of a new tool including an experiment and a numerical calculation for the estimation of the thermal contact conductance between the fin collar and tube surface, and pursues the evaluation of the factors affecting the thermal contact conductance in a fin-tube heat exchanger. Heat exchangers fabricated for the current study have been put to the test for heat balance in a vacuum chamber with water as an internal fluid. And a finite difference numerical scheme has been used for the data reduction of the experimental data to evaluate the thermal contact conductance. Fin-tube heat exchangers employed in the current research are of tube diameter of 7 mm with different tube expansion ratios, fin spacings, and fin types. The results of the present study imply that these parameters as well as hydrophilic fin coating have a significant effect on the thermal contact conductance. It has been discovered that the portion of the thermal contact resistance is not negligible compared with the total thermal resistance in a fin-tube heat exchanger, and this means that in order to reduce the thermal contact resistance thoughtful care should be taken in fabricating heat exchangers. [Copyright &y& Elsevier]